Merge tag 'rtc-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux
[linux-2.6-block.git] / drivers / tty / serial / samsung.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver core for Samsung SoC onboard UARTs.
4  *
5  * Ben Dooks, Copyright (c) 2003-2008 Simtec Electronics
6  *      http://armlinux.simtec.co.uk/
7 */
8
9 /* Hote on 2410 error handling
10  *
11  * The s3c2410 manual has a love/hate affair with the contents of the
12  * UERSTAT register in the UART blocks, and keeps marking some of the
13  * error bits as reserved. Having checked with the s3c2410x01,
14  * it copes with BREAKs properly, so I am happy to ignore the RESERVED
15  * feature from the latter versions of the manual.
16  *
17  * If it becomes aparrent that latter versions of the 2410 remove these
18  * bits, then action will have to be taken to differentiate the versions
19  * and change the policy on BREAK
20  *
21  * BJD, 04-Nov-2004
22 */
23
24 #if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
25 #define SUPPORT_SYSRQ
26 #endif
27
28 #include <linux/dmaengine.h>
29 #include <linux/dma-mapping.h>
30 #include <linux/slab.h>
31 #include <linux/module.h>
32 #include <linux/ioport.h>
33 #include <linux/io.h>
34 #include <linux/platform_device.h>
35 #include <linux/init.h>
36 #include <linux/sysrq.h>
37 #include <linux/console.h>
38 #include <linux/tty.h>
39 #include <linux/tty_flip.h>
40 #include <linux/serial_core.h>
41 #include <linux/serial.h>
42 #include <linux/serial_s3c.h>
43 #include <linux/delay.h>
44 #include <linux/clk.h>
45 #include <linux/cpufreq.h>
46 #include <linux/of.h>
47
48 #include <asm/irq.h>
49
50 #include "samsung.h"
51
52 #if     defined(CONFIG_SERIAL_SAMSUNG_DEBUG) && \
53         !defined(MODULE)
54
55 extern void printascii(const char *);
56
57 __printf(1, 2)
58 static void dbg(const char *fmt, ...)
59 {
60         va_list va;
61         char buff[256];
62
63         va_start(va, fmt);
64         vscnprintf(buff, sizeof(buff), fmt, va);
65         va_end(va);
66
67         printascii(buff);
68 }
69
70 #else
71 #define dbg(fmt, ...) do { if (0) no_printk(fmt, ##__VA_ARGS__); } while (0)
72 #endif
73
74 /* UART name and device definitions */
75
76 #define S3C24XX_SERIAL_NAME     "ttySAC"
77 #define S3C24XX_SERIAL_MAJOR    204
78 #define S3C24XX_SERIAL_MINOR    64
79
80 #define S3C24XX_TX_PIO                  1
81 #define S3C24XX_TX_DMA                  2
82 #define S3C24XX_RX_PIO                  1
83 #define S3C24XX_RX_DMA                  2
84 /* macros to change one thing to another */
85
86 #define tx_enabled(port) ((port)->unused[0])
87 #define rx_enabled(port) ((port)->unused[1])
88
89 /* flag to ignore all characters coming in */
90 #define RXSTAT_DUMMY_READ (0x10000000)
91
92 static inline struct s3c24xx_uart_port *to_ourport(struct uart_port *port)
93 {
94         return container_of(port, struct s3c24xx_uart_port, port);
95 }
96
97 /* translate a port to the device name */
98
99 static inline const char *s3c24xx_serial_portname(struct uart_port *port)
100 {
101         return to_platform_device(port->dev)->name;
102 }
103
104 static int s3c24xx_serial_txempty_nofifo(struct uart_port *port)
105 {
106         return rd_regl(port, S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXE;
107 }
108
109 /*
110  * s3c64xx and later SoC's include the interrupt mask and status registers in
111  * the controller itself, unlike the s3c24xx SoC's which have these registers
112  * in the interrupt controller. Check if the port type is s3c64xx or higher.
113  */
114 static int s3c24xx_serial_has_interrupt_mask(struct uart_port *port)
115 {
116         return to_ourport(port)->info->type == PORT_S3C6400;
117 }
118
119 static void s3c24xx_serial_rx_enable(struct uart_port *port)
120 {
121         unsigned long flags;
122         unsigned int ucon, ufcon;
123         int count = 10000;
124
125         spin_lock_irqsave(&port->lock, flags);
126
127         while (--count && !s3c24xx_serial_txempty_nofifo(port))
128                 udelay(100);
129
130         ufcon = rd_regl(port, S3C2410_UFCON);
131         ufcon |= S3C2410_UFCON_RESETRX;
132         wr_regl(port, S3C2410_UFCON, ufcon);
133
134         ucon = rd_regl(port, S3C2410_UCON);
135         ucon |= S3C2410_UCON_RXIRQMODE;
136         wr_regl(port, S3C2410_UCON, ucon);
137
138         rx_enabled(port) = 1;
139         spin_unlock_irqrestore(&port->lock, flags);
140 }
141
142 static void s3c24xx_serial_rx_disable(struct uart_port *port)
143 {
144         unsigned long flags;
145         unsigned int ucon;
146
147         spin_lock_irqsave(&port->lock, flags);
148
149         ucon = rd_regl(port, S3C2410_UCON);
150         ucon &= ~S3C2410_UCON_RXIRQMODE;
151         wr_regl(port, S3C2410_UCON, ucon);
152
153         rx_enabled(port) = 0;
154         spin_unlock_irqrestore(&port->lock, flags);
155 }
156
157 static void s3c24xx_serial_stop_tx(struct uart_port *port)
158 {
159         struct s3c24xx_uart_port *ourport = to_ourport(port);
160         struct s3c24xx_uart_dma *dma = ourport->dma;
161         struct circ_buf *xmit = &port->state->xmit;
162         struct dma_tx_state state;
163         int count;
164
165         if (!tx_enabled(port))
166                 return;
167
168         if (s3c24xx_serial_has_interrupt_mask(port))
169                 s3c24xx_set_bit(port, S3C64XX_UINTM_TXD, S3C64XX_UINTM);
170         else
171                 disable_irq_nosync(ourport->tx_irq);
172
173         if (dma && dma->tx_chan && ourport->tx_in_progress == S3C24XX_TX_DMA) {
174                 dmaengine_pause(dma->tx_chan);
175                 dmaengine_tx_status(dma->tx_chan, dma->tx_cookie, &state);
176                 dmaengine_terminate_all(dma->tx_chan);
177                 dma_sync_single_for_cpu(ourport->port.dev,
178                         dma->tx_transfer_addr, dma->tx_size, DMA_TO_DEVICE);
179                 async_tx_ack(dma->tx_desc);
180                 count = dma->tx_bytes_requested - state.residue;
181                 xmit->tail = (xmit->tail + count) & (UART_XMIT_SIZE - 1);
182                 port->icount.tx += count;
183         }
184
185         tx_enabled(port) = 0;
186         ourport->tx_in_progress = 0;
187
188         if (port->flags & UPF_CONS_FLOW)
189                 s3c24xx_serial_rx_enable(port);
190
191         ourport->tx_mode = 0;
192 }
193
194 static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport);
195
196 static void s3c24xx_serial_tx_dma_complete(void *args)
197 {
198         struct s3c24xx_uart_port *ourport = args;
199         struct uart_port *port = &ourport->port;
200         struct circ_buf *xmit = &port->state->xmit;
201         struct s3c24xx_uart_dma *dma = ourport->dma;
202         struct dma_tx_state state;
203         unsigned long flags;
204         int count;
205
206
207         dmaengine_tx_status(dma->tx_chan, dma->tx_cookie, &state);
208         count = dma->tx_bytes_requested - state.residue;
209         async_tx_ack(dma->tx_desc);
210
211         dma_sync_single_for_cpu(ourport->port.dev, dma->tx_transfer_addr,
212                                 dma->tx_size, DMA_TO_DEVICE);
213
214         spin_lock_irqsave(&port->lock, flags);
215
216         xmit->tail = (xmit->tail + count) & (UART_XMIT_SIZE - 1);
217         port->icount.tx += count;
218         ourport->tx_in_progress = 0;
219
220         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
221                 uart_write_wakeup(port);
222
223         s3c24xx_serial_start_next_tx(ourport);
224         spin_unlock_irqrestore(&port->lock, flags);
225 }
226
227 static void enable_tx_dma(struct s3c24xx_uart_port *ourport)
228 {
229         struct uart_port *port = &ourport->port;
230         u32 ucon;
231
232         /* Mask Tx interrupt */
233         if (s3c24xx_serial_has_interrupt_mask(port))
234                 s3c24xx_set_bit(port, S3C64XX_UINTM_TXD, S3C64XX_UINTM);
235         else
236                 disable_irq_nosync(ourport->tx_irq);
237
238         /* Enable tx dma mode */
239         ucon = rd_regl(port, S3C2410_UCON);
240         ucon &= ~(S3C64XX_UCON_TXBURST_MASK | S3C64XX_UCON_TXMODE_MASK);
241         ucon |= (dma_get_cache_alignment() >= 16) ?
242                 S3C64XX_UCON_TXBURST_16 : S3C64XX_UCON_TXBURST_1;
243         ucon |= S3C64XX_UCON_TXMODE_DMA;
244         wr_regl(port,  S3C2410_UCON, ucon);
245
246         ourport->tx_mode = S3C24XX_TX_DMA;
247 }
248
249 static void enable_tx_pio(struct s3c24xx_uart_port *ourport)
250 {
251         struct uart_port *port = &ourport->port;
252         u32 ucon, ufcon;
253
254         /* Set ufcon txtrig */
255         ourport->tx_in_progress = S3C24XX_TX_PIO;
256         ufcon = rd_regl(port, S3C2410_UFCON);
257         wr_regl(port,  S3C2410_UFCON, ufcon);
258
259         /* Enable tx pio mode */
260         ucon = rd_regl(port, S3C2410_UCON);
261         ucon &= ~(S3C64XX_UCON_TXMODE_MASK);
262         ucon |= S3C64XX_UCON_TXMODE_CPU;
263         wr_regl(port,  S3C2410_UCON, ucon);
264
265         /* Unmask Tx interrupt */
266         if (s3c24xx_serial_has_interrupt_mask(port))
267                 s3c24xx_clear_bit(port, S3C64XX_UINTM_TXD,
268                                   S3C64XX_UINTM);
269         else
270                 enable_irq(ourport->tx_irq);
271
272         ourport->tx_mode = S3C24XX_TX_PIO;
273 }
274
275 static void s3c24xx_serial_start_tx_pio(struct s3c24xx_uart_port *ourport)
276 {
277         if (ourport->tx_mode != S3C24XX_TX_PIO)
278                 enable_tx_pio(ourport);
279 }
280
281 static int s3c24xx_serial_start_tx_dma(struct s3c24xx_uart_port *ourport,
282                                       unsigned int count)
283 {
284         struct uart_port *port = &ourport->port;
285         struct circ_buf *xmit = &port->state->xmit;
286         struct s3c24xx_uart_dma *dma = ourport->dma;
287
288
289         if (ourport->tx_mode != S3C24XX_TX_DMA)
290                 enable_tx_dma(ourport);
291
292         dma->tx_size = count & ~(dma_get_cache_alignment() - 1);
293         dma->tx_transfer_addr = dma->tx_addr + xmit->tail;
294
295         dma_sync_single_for_device(ourport->port.dev, dma->tx_transfer_addr,
296                                 dma->tx_size, DMA_TO_DEVICE);
297
298         dma->tx_desc = dmaengine_prep_slave_single(dma->tx_chan,
299                                 dma->tx_transfer_addr, dma->tx_size,
300                                 DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT);
301         if (!dma->tx_desc) {
302                 dev_err(ourport->port.dev, "Unable to get desc for Tx\n");
303                 return -EIO;
304         }
305
306         dma->tx_desc->callback = s3c24xx_serial_tx_dma_complete;
307         dma->tx_desc->callback_param = ourport;
308         dma->tx_bytes_requested = dma->tx_size;
309
310         ourport->tx_in_progress = S3C24XX_TX_DMA;
311         dma->tx_cookie = dmaengine_submit(dma->tx_desc);
312         dma_async_issue_pending(dma->tx_chan);
313         return 0;
314 }
315
316 static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport)
317 {
318         struct uart_port *port = &ourport->port;
319         struct circ_buf *xmit = &port->state->xmit;
320         unsigned long count;
321
322         /* Get data size up to the end of buffer */
323         count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
324
325         if (!count) {
326                 s3c24xx_serial_stop_tx(port);
327                 return;
328         }
329
330         if (!ourport->dma || !ourport->dma->tx_chan ||
331             count < ourport->min_dma_size ||
332             xmit->tail & (dma_get_cache_alignment() - 1))
333                 s3c24xx_serial_start_tx_pio(ourport);
334         else
335                 s3c24xx_serial_start_tx_dma(ourport, count);
336 }
337
338 static void s3c24xx_serial_start_tx(struct uart_port *port)
339 {
340         struct s3c24xx_uart_port *ourport = to_ourport(port);
341         struct circ_buf *xmit = &port->state->xmit;
342
343         if (!tx_enabled(port)) {
344                 if (port->flags & UPF_CONS_FLOW)
345                         s3c24xx_serial_rx_disable(port);
346
347                 tx_enabled(port) = 1;
348                 if (!ourport->dma || !ourport->dma->tx_chan)
349                         s3c24xx_serial_start_tx_pio(ourport);
350         }
351
352         if (ourport->dma && ourport->dma->tx_chan) {
353                 if (!uart_circ_empty(xmit) && !ourport->tx_in_progress)
354                         s3c24xx_serial_start_next_tx(ourport);
355         }
356 }
357
358 static void s3c24xx_uart_copy_rx_to_tty(struct s3c24xx_uart_port *ourport,
359                 struct tty_port *tty, int count)
360 {
361         struct s3c24xx_uart_dma *dma = ourport->dma;
362         int copied;
363
364         if (!count)
365                 return;
366
367         dma_sync_single_for_cpu(ourport->port.dev, dma->rx_addr,
368                                 dma->rx_size, DMA_FROM_DEVICE);
369
370         ourport->port.icount.rx += count;
371         if (!tty) {
372                 dev_err(ourport->port.dev, "No tty port\n");
373                 return;
374         }
375         copied = tty_insert_flip_string(tty,
376                         ((unsigned char *)(ourport->dma->rx_buf)), count);
377         if (copied != count) {
378                 WARN_ON(1);
379                 dev_err(ourport->port.dev, "RxData copy to tty layer failed\n");
380         }
381 }
382
383 static void s3c24xx_serial_stop_rx(struct uart_port *port)
384 {
385         struct s3c24xx_uart_port *ourport = to_ourport(port);
386         struct s3c24xx_uart_dma *dma = ourport->dma;
387         struct tty_port *t = &port->state->port;
388         struct dma_tx_state state;
389         enum dma_status dma_status;
390         unsigned int received;
391
392         if (rx_enabled(port)) {
393                 dbg("s3c24xx_serial_stop_rx: port=%p\n", port);
394                 if (s3c24xx_serial_has_interrupt_mask(port))
395                         s3c24xx_set_bit(port, S3C64XX_UINTM_RXD,
396                                         S3C64XX_UINTM);
397                 else
398                         disable_irq_nosync(ourport->rx_irq);
399                 rx_enabled(port) = 0;
400         }
401         if (dma && dma->rx_chan) {
402                 dmaengine_pause(dma->tx_chan);
403                 dma_status = dmaengine_tx_status(dma->rx_chan,
404                                 dma->rx_cookie, &state);
405                 if (dma_status == DMA_IN_PROGRESS ||
406                         dma_status == DMA_PAUSED) {
407                         received = dma->rx_bytes_requested - state.residue;
408                         dmaengine_terminate_all(dma->rx_chan);
409                         s3c24xx_uart_copy_rx_to_tty(ourport, t, received);
410                 }
411         }
412 }
413
414 static inline struct s3c24xx_uart_info
415         *s3c24xx_port_to_info(struct uart_port *port)
416 {
417         return to_ourport(port)->info;
418 }
419
420 static inline struct s3c2410_uartcfg
421         *s3c24xx_port_to_cfg(struct uart_port *port)
422 {
423         struct s3c24xx_uart_port *ourport;
424
425         if (port->dev == NULL)
426                 return NULL;
427
428         ourport = container_of(port, struct s3c24xx_uart_port, port);
429         return ourport->cfg;
430 }
431
432 static int s3c24xx_serial_rx_fifocnt(struct s3c24xx_uart_port *ourport,
433                                      unsigned long ufstat)
434 {
435         struct s3c24xx_uart_info *info = ourport->info;
436
437         if (ufstat & info->rx_fifofull)
438                 return ourport->port.fifosize;
439
440         return (ufstat & info->rx_fifomask) >> info->rx_fifoshift;
441 }
442
443 static void s3c64xx_start_rx_dma(struct s3c24xx_uart_port *ourport);
444 static void s3c24xx_serial_rx_dma_complete(void *args)
445 {
446         struct s3c24xx_uart_port *ourport = args;
447         struct uart_port *port = &ourport->port;
448
449         struct s3c24xx_uart_dma *dma = ourport->dma;
450         struct tty_port *t = &port->state->port;
451         struct tty_struct *tty = tty_port_tty_get(&ourport->port.state->port);
452
453         struct dma_tx_state state;
454         unsigned long flags;
455         int received;
456
457         dmaengine_tx_status(dma->rx_chan,  dma->rx_cookie, &state);
458         received  = dma->rx_bytes_requested - state.residue;
459         async_tx_ack(dma->rx_desc);
460
461         spin_lock_irqsave(&port->lock, flags);
462
463         if (received)
464                 s3c24xx_uart_copy_rx_to_tty(ourport, t, received);
465
466         if (tty) {
467                 tty_flip_buffer_push(t);
468                 tty_kref_put(tty);
469         }
470
471         s3c64xx_start_rx_dma(ourport);
472
473         spin_unlock_irqrestore(&port->lock, flags);
474 }
475
476 static void s3c64xx_start_rx_dma(struct s3c24xx_uart_port *ourport)
477 {
478         struct s3c24xx_uart_dma *dma = ourport->dma;
479
480         dma_sync_single_for_device(ourport->port.dev, dma->rx_addr,
481                                 dma->rx_size, DMA_FROM_DEVICE);
482
483         dma->rx_desc = dmaengine_prep_slave_single(dma->rx_chan,
484                                 dma->rx_addr, dma->rx_size, DMA_DEV_TO_MEM,
485                                 DMA_PREP_INTERRUPT);
486         if (!dma->rx_desc) {
487                 dev_err(ourport->port.dev, "Unable to get desc for Rx\n");
488                 return;
489         }
490
491         dma->rx_desc->callback = s3c24xx_serial_rx_dma_complete;
492         dma->rx_desc->callback_param = ourport;
493         dma->rx_bytes_requested = dma->rx_size;
494
495         dma->rx_cookie = dmaengine_submit(dma->rx_desc);
496         dma_async_issue_pending(dma->rx_chan);
497 }
498
499 /* ? - where has parity gone?? */
500 #define S3C2410_UERSTAT_PARITY (0x1000)
501
502 static void enable_rx_dma(struct s3c24xx_uart_port *ourport)
503 {
504         struct uart_port *port = &ourport->port;
505         unsigned int ucon;
506
507         /* set Rx mode to DMA mode */
508         ucon = rd_regl(port, S3C2410_UCON);
509         ucon &= ~(S3C64XX_UCON_RXBURST_MASK |
510                         S3C64XX_UCON_TIMEOUT_MASK |
511                         S3C64XX_UCON_EMPTYINT_EN |
512                         S3C64XX_UCON_DMASUS_EN |
513                         S3C64XX_UCON_TIMEOUT_EN |
514                         S3C64XX_UCON_RXMODE_MASK);
515         ucon |= S3C64XX_UCON_RXBURST_16 |
516                         0xf << S3C64XX_UCON_TIMEOUT_SHIFT |
517                         S3C64XX_UCON_EMPTYINT_EN |
518                         S3C64XX_UCON_TIMEOUT_EN |
519                         S3C64XX_UCON_RXMODE_DMA;
520         wr_regl(port, S3C2410_UCON, ucon);
521
522         ourport->rx_mode = S3C24XX_RX_DMA;
523 }
524
525 static void enable_rx_pio(struct s3c24xx_uart_port *ourport)
526 {
527         struct uart_port *port = &ourport->port;
528         unsigned int ucon;
529
530         /* set Rx mode to DMA mode */
531         ucon = rd_regl(port, S3C2410_UCON);
532         ucon &= ~(S3C64XX_UCON_TIMEOUT_MASK |
533                         S3C64XX_UCON_EMPTYINT_EN |
534                         S3C64XX_UCON_DMASUS_EN |
535                         S3C64XX_UCON_TIMEOUT_EN |
536                         S3C64XX_UCON_RXMODE_MASK);
537         ucon |= 0xf << S3C64XX_UCON_TIMEOUT_SHIFT |
538                         S3C64XX_UCON_TIMEOUT_EN |
539                         S3C64XX_UCON_RXMODE_CPU;
540         wr_regl(port, S3C2410_UCON, ucon);
541
542         ourport->rx_mode = S3C24XX_RX_PIO;
543 }
544
545 static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport);
546
547 static irqreturn_t s3c24xx_serial_rx_chars_dma(void *dev_id)
548 {
549         unsigned int utrstat, ufstat, received;
550         struct s3c24xx_uart_port *ourport = dev_id;
551         struct uart_port *port = &ourport->port;
552         struct s3c24xx_uart_dma *dma = ourport->dma;
553         struct tty_struct *tty = tty_port_tty_get(&ourport->port.state->port);
554         struct tty_port *t = &port->state->port;
555         unsigned long flags;
556         struct dma_tx_state state;
557
558         utrstat = rd_regl(port, S3C2410_UTRSTAT);
559         ufstat = rd_regl(port, S3C2410_UFSTAT);
560
561         spin_lock_irqsave(&port->lock, flags);
562
563         if (!(utrstat & S3C2410_UTRSTAT_TIMEOUT)) {
564                 s3c64xx_start_rx_dma(ourport);
565                 if (ourport->rx_mode == S3C24XX_RX_PIO)
566                         enable_rx_dma(ourport);
567                 goto finish;
568         }
569
570         if (ourport->rx_mode == S3C24XX_RX_DMA) {
571                 dmaengine_pause(dma->rx_chan);
572                 dmaengine_tx_status(dma->rx_chan, dma->rx_cookie, &state);
573                 dmaengine_terminate_all(dma->rx_chan);
574                 received = dma->rx_bytes_requested - state.residue;
575                 s3c24xx_uart_copy_rx_to_tty(ourport, t, received);
576
577                 enable_rx_pio(ourport);
578         }
579
580         s3c24xx_serial_rx_drain_fifo(ourport);
581
582         if (tty) {
583                 tty_flip_buffer_push(t);
584                 tty_kref_put(tty);
585         }
586
587         wr_regl(port, S3C2410_UTRSTAT, S3C2410_UTRSTAT_TIMEOUT);
588
589 finish:
590         spin_unlock_irqrestore(&port->lock, flags);
591
592         return IRQ_HANDLED;
593 }
594
595 static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport)
596 {
597         struct uart_port *port = &ourport->port;
598         unsigned int ufcon, ch, flag, ufstat, uerstat;
599         unsigned int fifocnt = 0;
600         int max_count = port->fifosize;
601
602         while (max_count-- > 0) {
603                 /*
604                  * Receive all characters known to be in FIFO
605                  * before reading FIFO level again
606                  */
607                 if (fifocnt == 0) {
608                         ufstat = rd_regl(port, S3C2410_UFSTAT);
609                         fifocnt = s3c24xx_serial_rx_fifocnt(ourport, ufstat);
610                         if (fifocnt == 0)
611                                 break;
612                 }
613                 fifocnt--;
614
615                 uerstat = rd_regl(port, S3C2410_UERSTAT);
616                 ch = rd_regb(port, S3C2410_URXH);
617
618                 if (port->flags & UPF_CONS_FLOW) {
619                         int txe = s3c24xx_serial_txempty_nofifo(port);
620
621                         if (rx_enabled(port)) {
622                                 if (!txe) {
623                                         rx_enabled(port) = 0;
624                                         continue;
625                                 }
626                         } else {
627                                 if (txe) {
628                                         ufcon = rd_regl(port, S3C2410_UFCON);
629                                         ufcon |= S3C2410_UFCON_RESETRX;
630                                         wr_regl(port, S3C2410_UFCON, ufcon);
631                                         rx_enabled(port) = 1;
632                                         return;
633                                 }
634                                 continue;
635                         }
636                 }
637
638                 /* insert the character into the buffer */
639
640                 flag = TTY_NORMAL;
641                 port->icount.rx++;
642
643                 if (unlikely(uerstat & S3C2410_UERSTAT_ANY)) {
644                         dbg("rxerr: port ch=0x%02x, rxs=0x%08x\n",
645                             ch, uerstat);
646
647                         /* check for break */
648                         if (uerstat & S3C2410_UERSTAT_BREAK) {
649                                 dbg("break!\n");
650                                 port->icount.brk++;
651                                 if (uart_handle_break(port))
652                                         continue; /* Ignore character */
653                         }
654
655                         if (uerstat & S3C2410_UERSTAT_FRAME)
656                                 port->icount.frame++;
657                         if (uerstat & S3C2410_UERSTAT_OVERRUN)
658                                 port->icount.overrun++;
659
660                         uerstat &= port->read_status_mask;
661
662                         if (uerstat & S3C2410_UERSTAT_BREAK)
663                                 flag = TTY_BREAK;
664                         else if (uerstat & S3C2410_UERSTAT_PARITY)
665                                 flag = TTY_PARITY;
666                         else if (uerstat & (S3C2410_UERSTAT_FRAME |
667                                             S3C2410_UERSTAT_OVERRUN))
668                                 flag = TTY_FRAME;
669                 }
670
671                 if (uart_handle_sysrq_char(port, ch))
672                         continue; /* Ignore character */
673
674                 uart_insert_char(port, uerstat, S3C2410_UERSTAT_OVERRUN,
675                                  ch, flag);
676         }
677
678         tty_flip_buffer_push(&port->state->port);
679 }
680
681 static irqreturn_t s3c24xx_serial_rx_chars_pio(void *dev_id)
682 {
683         struct s3c24xx_uart_port *ourport = dev_id;
684         struct uart_port *port = &ourport->port;
685         unsigned long flags;
686
687         spin_lock_irqsave(&port->lock, flags);
688         s3c24xx_serial_rx_drain_fifo(ourport);
689         spin_unlock_irqrestore(&port->lock, flags);
690
691         return IRQ_HANDLED;
692 }
693
694
695 static irqreturn_t s3c24xx_serial_rx_chars(int irq, void *dev_id)
696 {
697         struct s3c24xx_uart_port *ourport = dev_id;
698
699         if (ourport->dma && ourport->dma->rx_chan)
700                 return s3c24xx_serial_rx_chars_dma(dev_id);
701         return s3c24xx_serial_rx_chars_pio(dev_id);
702 }
703
704 static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id)
705 {
706         struct s3c24xx_uart_port *ourport = id;
707         struct uart_port *port = &ourport->port;
708         struct circ_buf *xmit = &port->state->xmit;
709         unsigned long flags;
710         int count, dma_count = 0;
711
712         spin_lock_irqsave(&port->lock, flags);
713
714         count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
715
716         if (ourport->dma && ourport->dma->tx_chan &&
717             count >= ourport->min_dma_size) {
718                 int align = dma_get_cache_alignment() -
719                         (xmit->tail & (dma_get_cache_alignment() - 1));
720                 if (count-align >= ourport->min_dma_size) {
721                         dma_count = count-align;
722                         count = align;
723                 }
724         }
725
726         if (port->x_char) {
727                 wr_regb(port, S3C2410_UTXH, port->x_char);
728                 port->icount.tx++;
729                 port->x_char = 0;
730                 goto out;
731         }
732
733         /* if there isn't anything more to transmit, or the uart is now
734          * stopped, disable the uart and exit
735         */
736
737         if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
738                 s3c24xx_serial_stop_tx(port);
739                 goto out;
740         }
741
742         /* try and drain the buffer... */
743
744         if (count > port->fifosize) {
745                 count = port->fifosize;
746                 dma_count = 0;
747         }
748
749         while (!uart_circ_empty(xmit) && count > 0) {
750                 if (rd_regl(port, S3C2410_UFSTAT) & ourport->info->tx_fifofull)
751                         break;
752
753                 wr_regb(port, S3C2410_UTXH, xmit->buf[xmit->tail]);
754                 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
755                 port->icount.tx++;
756                 count--;
757         }
758
759         if (!count && dma_count) {
760                 s3c24xx_serial_start_tx_dma(ourport, dma_count);
761                 goto out;
762         }
763
764         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) {
765                 spin_unlock(&port->lock);
766                 uart_write_wakeup(port);
767                 spin_lock(&port->lock);
768         }
769
770         if (uart_circ_empty(xmit))
771                 s3c24xx_serial_stop_tx(port);
772
773 out:
774         spin_unlock_irqrestore(&port->lock, flags);
775         return IRQ_HANDLED;
776 }
777
778 /* interrupt handler for s3c64xx and later SoC's.*/
779 static irqreturn_t s3c64xx_serial_handle_irq(int irq, void *id)
780 {
781         struct s3c24xx_uart_port *ourport = id;
782         struct uart_port *port = &ourport->port;
783         unsigned int pend = rd_regl(port, S3C64XX_UINTP);
784         irqreturn_t ret = IRQ_HANDLED;
785
786         if (pend & S3C64XX_UINTM_RXD_MSK) {
787                 ret = s3c24xx_serial_rx_chars(irq, id);
788                 wr_regl(port, S3C64XX_UINTP, S3C64XX_UINTM_RXD_MSK);
789         }
790         if (pend & S3C64XX_UINTM_TXD_MSK) {
791                 ret = s3c24xx_serial_tx_chars(irq, id);
792                 wr_regl(port, S3C64XX_UINTP, S3C64XX_UINTM_TXD_MSK);
793         }
794         return ret;
795 }
796
797 static unsigned int s3c24xx_serial_tx_empty(struct uart_port *port)
798 {
799         struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
800         unsigned long ufstat = rd_regl(port, S3C2410_UFSTAT);
801         unsigned long ufcon = rd_regl(port, S3C2410_UFCON);
802
803         if (ufcon & S3C2410_UFCON_FIFOMODE) {
804                 if ((ufstat & info->tx_fifomask) != 0 ||
805                     (ufstat & info->tx_fifofull))
806                         return 0;
807
808                 return 1;
809         }
810
811         return s3c24xx_serial_txempty_nofifo(port);
812 }
813
814 /* no modem control lines */
815 static unsigned int s3c24xx_serial_get_mctrl(struct uart_port *port)
816 {
817         unsigned int umstat = rd_regb(port, S3C2410_UMSTAT);
818
819         if (umstat & S3C2410_UMSTAT_CTS)
820                 return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
821         else
822                 return TIOCM_CAR | TIOCM_DSR;
823 }
824
825 static void s3c24xx_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)
826 {
827         unsigned int umcon = rd_regl(port, S3C2410_UMCON);
828
829         if (mctrl & TIOCM_RTS)
830                 umcon |= S3C2410_UMCOM_RTS_LOW;
831         else
832                 umcon &= ~S3C2410_UMCOM_RTS_LOW;
833
834         wr_regl(port, S3C2410_UMCON, umcon);
835 }
836
837 static void s3c24xx_serial_break_ctl(struct uart_port *port, int break_state)
838 {
839         unsigned long flags;
840         unsigned int ucon;
841
842         spin_lock_irqsave(&port->lock, flags);
843
844         ucon = rd_regl(port, S3C2410_UCON);
845
846         if (break_state)
847                 ucon |= S3C2410_UCON_SBREAK;
848         else
849                 ucon &= ~S3C2410_UCON_SBREAK;
850
851         wr_regl(port, S3C2410_UCON, ucon);
852
853         spin_unlock_irqrestore(&port->lock, flags);
854 }
855
856 static int s3c24xx_serial_request_dma(struct s3c24xx_uart_port *p)
857 {
858         struct s3c24xx_uart_dma *dma = p->dma;
859         struct dma_slave_caps dma_caps;
860         const char *reason = NULL;
861         int ret;
862
863         /* Default slave configuration parameters */
864         dma->rx_conf.direction          = DMA_DEV_TO_MEM;
865         dma->rx_conf.src_addr_width     = DMA_SLAVE_BUSWIDTH_1_BYTE;
866         dma->rx_conf.src_addr           = p->port.mapbase + S3C2410_URXH;
867         dma->rx_conf.src_maxburst       = 1;
868
869         dma->tx_conf.direction          = DMA_MEM_TO_DEV;
870         dma->tx_conf.dst_addr_width     = DMA_SLAVE_BUSWIDTH_1_BYTE;
871         dma->tx_conf.dst_addr           = p->port.mapbase + S3C2410_UTXH;
872         dma->tx_conf.dst_maxburst       = 1;
873
874         dma->rx_chan = dma_request_chan(p->port.dev, "rx");
875
876         if (IS_ERR(dma->rx_chan)) {
877                 reason = "DMA RX channel request failed";
878                 ret = PTR_ERR(dma->rx_chan);
879                 goto err_warn;
880         }
881
882         ret = dma_get_slave_caps(dma->rx_chan, &dma_caps);
883         if (ret < 0 ||
884             dma_caps.residue_granularity < DMA_RESIDUE_GRANULARITY_BURST) {
885                 reason = "insufficient DMA RX engine capabilities";
886                 ret = -EOPNOTSUPP;
887                 goto err_release_rx;
888         }
889
890         dmaengine_slave_config(dma->rx_chan, &dma->rx_conf);
891
892         dma->tx_chan = dma_request_chan(p->port.dev, "tx");
893         if (IS_ERR(dma->tx_chan)) {
894                 reason = "DMA TX channel request failed";
895                 ret = PTR_ERR(dma->tx_chan);
896                 goto err_release_rx;
897         }
898
899         ret = dma_get_slave_caps(dma->tx_chan, &dma_caps);
900         if (ret < 0 ||
901             dma_caps.residue_granularity < DMA_RESIDUE_GRANULARITY_BURST) {
902                 reason = "insufficient DMA TX engine capabilities";
903                 ret = -EOPNOTSUPP;
904                 goto err_release_tx;
905         }
906
907         dmaengine_slave_config(dma->tx_chan, &dma->tx_conf);
908
909         /* RX buffer */
910         dma->rx_size = PAGE_SIZE;
911
912         dma->rx_buf = kmalloc(dma->rx_size, GFP_KERNEL);
913         if (!dma->rx_buf) {
914                 ret = -ENOMEM;
915                 goto err_release_tx;
916         }
917
918         dma->rx_addr = dma_map_single(p->port.dev, dma->rx_buf,
919                                 dma->rx_size, DMA_FROM_DEVICE);
920         if (dma_mapping_error(p->port.dev, dma->rx_addr)) {
921                 reason = "DMA mapping error for RX buffer";
922                 ret = -EIO;
923                 goto err_free_rx;
924         }
925
926         /* TX buffer */
927         dma->tx_addr = dma_map_single(p->port.dev, p->port.state->xmit.buf,
928                                 UART_XMIT_SIZE, DMA_TO_DEVICE);
929         if (dma_mapping_error(p->port.dev, dma->tx_addr)) {
930                 reason = "DMA mapping error for TX buffer";
931                 ret = -EIO;
932                 goto err_unmap_rx;
933         }
934
935         return 0;
936
937 err_unmap_rx:
938         dma_unmap_single(p->port.dev, dma->rx_addr, dma->rx_size,
939                          DMA_FROM_DEVICE);
940 err_free_rx:
941         kfree(dma->rx_buf);
942 err_release_tx:
943         dma_release_channel(dma->tx_chan);
944 err_release_rx:
945         dma_release_channel(dma->rx_chan);
946 err_warn:
947         if (reason)
948                 dev_warn(p->port.dev, "%s, DMA will not be used\n", reason);
949         return ret;
950 }
951
952 static void s3c24xx_serial_release_dma(struct s3c24xx_uart_port *p)
953 {
954         struct s3c24xx_uart_dma *dma = p->dma;
955
956         if (dma->rx_chan) {
957                 dmaengine_terminate_all(dma->rx_chan);
958                 dma_unmap_single(p->port.dev, dma->rx_addr,
959                                 dma->rx_size, DMA_FROM_DEVICE);
960                 kfree(dma->rx_buf);
961                 dma_release_channel(dma->rx_chan);
962                 dma->rx_chan = NULL;
963         }
964
965         if (dma->tx_chan) {
966                 dmaengine_terminate_all(dma->tx_chan);
967                 dma_unmap_single(p->port.dev, dma->tx_addr,
968                                 UART_XMIT_SIZE, DMA_TO_DEVICE);
969                 dma_release_channel(dma->tx_chan);
970                 dma->tx_chan = NULL;
971         }
972 }
973
974 static void s3c24xx_serial_shutdown(struct uart_port *port)
975 {
976         struct s3c24xx_uart_port *ourport = to_ourport(port);
977
978         if (ourport->tx_claimed) {
979                 if (!s3c24xx_serial_has_interrupt_mask(port))
980                         free_irq(ourport->tx_irq, ourport);
981                 tx_enabled(port) = 0;
982                 ourport->tx_claimed = 0;
983                 ourport->tx_mode = 0;
984         }
985
986         if (ourport->rx_claimed) {
987                 if (!s3c24xx_serial_has_interrupt_mask(port))
988                         free_irq(ourport->rx_irq, ourport);
989                 ourport->rx_claimed = 0;
990                 rx_enabled(port) = 0;
991         }
992
993         /* Clear pending interrupts and mask all interrupts */
994         if (s3c24xx_serial_has_interrupt_mask(port)) {
995                 free_irq(port->irq, ourport);
996
997                 wr_regl(port, S3C64XX_UINTP, 0xf);
998                 wr_regl(port, S3C64XX_UINTM, 0xf);
999         }
1000
1001         if (ourport->dma)
1002                 s3c24xx_serial_release_dma(ourport);
1003
1004         ourport->tx_in_progress = 0;
1005 }
1006
1007 static int s3c24xx_serial_startup(struct uart_port *port)
1008 {
1009         struct s3c24xx_uart_port *ourport = to_ourport(port);
1010         int ret;
1011
1012         dbg("s3c24xx_serial_startup: port=%p (%08llx,%p)\n",
1013             port, (unsigned long long)port->mapbase, port->membase);
1014
1015         rx_enabled(port) = 1;
1016
1017         ret = request_irq(ourport->rx_irq, s3c24xx_serial_rx_chars, 0,
1018                           s3c24xx_serial_portname(port), ourport);
1019
1020         if (ret != 0) {
1021                 dev_err(port->dev, "cannot get irq %d\n", ourport->rx_irq);
1022                 return ret;
1023         }
1024
1025         ourport->rx_claimed = 1;
1026
1027         dbg("requesting tx irq...\n");
1028
1029         tx_enabled(port) = 1;
1030
1031         ret = request_irq(ourport->tx_irq, s3c24xx_serial_tx_chars, 0,
1032                           s3c24xx_serial_portname(port), ourport);
1033
1034         if (ret) {
1035                 dev_err(port->dev, "cannot get irq %d\n", ourport->tx_irq);
1036                 goto err;
1037         }
1038
1039         ourport->tx_claimed = 1;
1040
1041         dbg("s3c24xx_serial_startup ok\n");
1042
1043         /* the port reset code should have done the correct
1044          * register setup for the port controls */
1045
1046         return ret;
1047
1048 err:
1049         s3c24xx_serial_shutdown(port);
1050         return ret;
1051 }
1052
1053 static int s3c64xx_serial_startup(struct uart_port *port)
1054 {
1055         struct s3c24xx_uart_port *ourport = to_ourport(port);
1056         unsigned long flags;
1057         unsigned int ufcon;
1058         int ret;
1059
1060         dbg("s3c64xx_serial_startup: port=%p (%08llx,%p)\n",
1061             port, (unsigned long long)port->mapbase, port->membase);
1062
1063         wr_regl(port, S3C64XX_UINTM, 0xf);
1064         if (ourport->dma) {
1065                 ret = s3c24xx_serial_request_dma(ourport);
1066                 if (ret < 0) {
1067                         devm_kfree(port->dev, ourport->dma);
1068                         ourport->dma = NULL;
1069                 }
1070         }
1071
1072         ret = request_irq(port->irq, s3c64xx_serial_handle_irq, IRQF_SHARED,
1073                           s3c24xx_serial_portname(port), ourport);
1074         if (ret) {
1075                 dev_err(port->dev, "cannot get irq %d\n", port->irq);
1076                 return ret;
1077         }
1078
1079         /* For compatibility with s3c24xx Soc's */
1080         rx_enabled(port) = 1;
1081         ourport->rx_claimed = 1;
1082         tx_enabled(port) = 0;
1083         ourport->tx_claimed = 1;
1084
1085         spin_lock_irqsave(&port->lock, flags);
1086
1087         ufcon = rd_regl(port, S3C2410_UFCON);
1088         ufcon |= S3C2410_UFCON_RESETRX | S5PV210_UFCON_RXTRIG8;
1089         if (!uart_console(port))
1090                 ufcon |= S3C2410_UFCON_RESETTX;
1091         wr_regl(port, S3C2410_UFCON, ufcon);
1092
1093         enable_rx_pio(ourport);
1094
1095         spin_unlock_irqrestore(&port->lock, flags);
1096
1097         /* Enable Rx Interrupt */
1098         s3c24xx_clear_bit(port, S3C64XX_UINTM_RXD, S3C64XX_UINTM);
1099
1100         dbg("s3c64xx_serial_startup ok\n");
1101         return ret;
1102 }
1103
1104 /* power power management control */
1105
1106 static void s3c24xx_serial_pm(struct uart_port *port, unsigned int level,
1107                               unsigned int old)
1108 {
1109         struct s3c24xx_uart_port *ourport = to_ourport(port);
1110         int timeout = 10000;
1111
1112         ourport->pm_level = level;
1113
1114         switch (level) {
1115         case 3:
1116                 while (--timeout && !s3c24xx_serial_txempty_nofifo(port))
1117                         udelay(100);
1118
1119                 if (!IS_ERR(ourport->baudclk))
1120                         clk_disable_unprepare(ourport->baudclk);
1121
1122                 clk_disable_unprepare(ourport->clk);
1123                 break;
1124
1125         case 0:
1126                 clk_prepare_enable(ourport->clk);
1127
1128                 if (!IS_ERR(ourport->baudclk))
1129                         clk_prepare_enable(ourport->baudclk);
1130
1131                 break;
1132         default:
1133                 dev_err(port->dev, "s3c24xx_serial: unknown pm %d\n", level);
1134         }
1135 }
1136
1137 /* baud rate calculation
1138  *
1139  * The UARTs on the S3C2410/S3C2440 can take their clocks from a number
1140  * of different sources, including the peripheral clock ("pclk") and an
1141  * external clock ("uclk"). The S3C2440 also adds the core clock ("fclk")
1142  * with a programmable extra divisor.
1143  *
1144  * The following code goes through the clock sources, and calculates the
1145  * baud clocks (and the resultant actual baud rates) and then tries to
1146  * pick the closest one and select that.
1147  *
1148 */
1149
1150 #define MAX_CLK_NAME_LENGTH 15
1151
1152 static inline int s3c24xx_serial_getsource(struct uart_port *port)
1153 {
1154         struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1155         unsigned int ucon;
1156
1157         if (info->num_clks == 1)
1158                 return 0;
1159
1160         ucon = rd_regl(port, S3C2410_UCON);
1161         ucon &= info->clksel_mask;
1162         return ucon >> info->clksel_shift;
1163 }
1164
1165 static void s3c24xx_serial_setsource(struct uart_port *port,
1166                         unsigned int clk_sel)
1167 {
1168         struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1169         unsigned int ucon;
1170
1171         if (info->num_clks == 1)
1172                 return;
1173
1174         ucon = rd_regl(port, S3C2410_UCON);
1175         if ((ucon & info->clksel_mask) >> info->clksel_shift == clk_sel)
1176                 return;
1177
1178         ucon &= ~info->clksel_mask;
1179         ucon |= clk_sel << info->clksel_shift;
1180         wr_regl(port, S3C2410_UCON, ucon);
1181 }
1182
1183 static unsigned int s3c24xx_serial_getclk(struct s3c24xx_uart_port *ourport,
1184                         unsigned int req_baud, struct clk **best_clk,
1185                         unsigned int *clk_num)
1186 {
1187         struct s3c24xx_uart_info *info = ourport->info;
1188         struct clk *clk;
1189         unsigned long rate;
1190         unsigned int cnt, baud, quot, clk_sel, best_quot = 0;
1191         char clkname[MAX_CLK_NAME_LENGTH];
1192         int calc_deviation, deviation = (1 << 30) - 1;
1193
1194         clk_sel = (ourport->cfg->clk_sel) ? ourport->cfg->clk_sel :
1195                         ourport->info->def_clk_sel;
1196         for (cnt = 0; cnt < info->num_clks; cnt++) {
1197                 if (!(clk_sel & (1 << cnt)))
1198                         continue;
1199
1200                 sprintf(clkname, "clk_uart_baud%d", cnt);
1201                 clk = clk_get(ourport->port.dev, clkname);
1202                 if (IS_ERR(clk))
1203                         continue;
1204
1205                 rate = clk_get_rate(clk);
1206                 if (!rate)
1207                         continue;
1208
1209                 if (ourport->info->has_divslot) {
1210                         unsigned long div = rate / req_baud;
1211
1212                         /* The UDIVSLOT register on the newer UARTs allows us to
1213                          * get a divisor adjustment of 1/16th on the baud clock.
1214                          *
1215                          * We don't keep the UDIVSLOT value (the 16ths we
1216                          * calculated by not multiplying the baud by 16) as it
1217                          * is easy enough to recalculate.
1218                          */
1219
1220                         quot = div / 16;
1221                         baud = rate / div;
1222                 } else {
1223                         quot = (rate + (8 * req_baud)) / (16 * req_baud);
1224                         baud = rate / (quot * 16);
1225                 }
1226                 quot--;
1227
1228                 calc_deviation = req_baud - baud;
1229                 if (calc_deviation < 0)
1230                         calc_deviation = -calc_deviation;
1231
1232                 if (calc_deviation < deviation) {
1233                         *best_clk = clk;
1234                         best_quot = quot;
1235                         *clk_num = cnt;
1236                         deviation = calc_deviation;
1237                 }
1238         }
1239
1240         return best_quot;
1241 }
1242
1243 /* udivslot_table[]
1244  *
1245  * This table takes the fractional value of the baud divisor and gives
1246  * the recommended setting for the UDIVSLOT register.
1247  */
1248 static u16 udivslot_table[16] = {
1249         [0] = 0x0000,
1250         [1] = 0x0080,
1251         [2] = 0x0808,
1252         [3] = 0x0888,
1253         [4] = 0x2222,
1254         [5] = 0x4924,
1255         [6] = 0x4A52,
1256         [7] = 0x54AA,
1257         [8] = 0x5555,
1258         [9] = 0xD555,
1259         [10] = 0xD5D5,
1260         [11] = 0xDDD5,
1261         [12] = 0xDDDD,
1262         [13] = 0xDFDD,
1263         [14] = 0xDFDF,
1264         [15] = 0xFFDF,
1265 };
1266
1267 static void s3c24xx_serial_set_termios(struct uart_port *port,
1268                                        struct ktermios *termios,
1269                                        struct ktermios *old)
1270 {
1271         struct s3c2410_uartcfg *cfg = s3c24xx_port_to_cfg(port);
1272         struct s3c24xx_uart_port *ourport = to_ourport(port);
1273         struct clk *clk = ERR_PTR(-EINVAL);
1274         unsigned long flags;
1275         unsigned int baud, quot, clk_sel = 0;
1276         unsigned int ulcon;
1277         unsigned int umcon;
1278         unsigned int udivslot = 0;
1279
1280         /*
1281          * We don't support modem control lines.
1282          */
1283         termios->c_cflag &= ~(HUPCL | CMSPAR);
1284         termios->c_cflag |= CLOCAL;
1285
1286         /*
1287          * Ask the core to calculate the divisor for us.
1288          */
1289
1290         baud = uart_get_baud_rate(port, termios, old, 0, 115200*8);
1291         quot = s3c24xx_serial_getclk(ourport, baud, &clk, &clk_sel);
1292         if (baud == 38400 && (port->flags & UPF_SPD_MASK) == UPF_SPD_CUST)
1293                 quot = port->custom_divisor;
1294         if (IS_ERR(clk))
1295                 return;
1296
1297         /* check to see if we need  to change clock source */
1298
1299         if (ourport->baudclk != clk) {
1300                 clk_prepare_enable(clk);
1301
1302                 s3c24xx_serial_setsource(port, clk_sel);
1303
1304                 if (!IS_ERR(ourport->baudclk)) {
1305                         clk_disable_unprepare(ourport->baudclk);
1306                         ourport->baudclk = ERR_PTR(-EINVAL);
1307                 }
1308
1309                 ourport->baudclk = clk;
1310                 ourport->baudclk_rate = clk ? clk_get_rate(clk) : 0;
1311         }
1312
1313         if (ourport->info->has_divslot) {
1314                 unsigned int div = ourport->baudclk_rate / baud;
1315
1316                 if (cfg->has_fracval) {
1317                         udivslot = (div & 15);
1318                         dbg("fracval = %04x\n", udivslot);
1319                 } else {
1320                         udivslot = udivslot_table[div & 15];
1321                         dbg("udivslot = %04x (div %d)\n", udivslot, div & 15);
1322                 }
1323         }
1324
1325         switch (termios->c_cflag & CSIZE) {
1326         case CS5:
1327                 dbg("config: 5bits/char\n");
1328                 ulcon = S3C2410_LCON_CS5;
1329                 break;
1330         case CS6:
1331                 dbg("config: 6bits/char\n");
1332                 ulcon = S3C2410_LCON_CS6;
1333                 break;
1334         case CS7:
1335                 dbg("config: 7bits/char\n");
1336                 ulcon = S3C2410_LCON_CS7;
1337                 break;
1338         case CS8:
1339         default:
1340                 dbg("config: 8bits/char\n");
1341                 ulcon = S3C2410_LCON_CS8;
1342                 break;
1343         }
1344
1345         /* preserve original lcon IR settings */
1346         ulcon |= (cfg->ulcon & S3C2410_LCON_IRM);
1347
1348         if (termios->c_cflag & CSTOPB)
1349                 ulcon |= S3C2410_LCON_STOPB;
1350
1351         if (termios->c_cflag & PARENB) {
1352                 if (termios->c_cflag & PARODD)
1353                         ulcon |= S3C2410_LCON_PODD;
1354                 else
1355                         ulcon |= S3C2410_LCON_PEVEN;
1356         } else {
1357                 ulcon |= S3C2410_LCON_PNONE;
1358         }
1359
1360         spin_lock_irqsave(&port->lock, flags);
1361
1362         dbg("setting ulcon to %08x, brddiv to %d, udivslot %08x\n",
1363             ulcon, quot, udivslot);
1364
1365         wr_regl(port, S3C2410_ULCON, ulcon);
1366         wr_regl(port, S3C2410_UBRDIV, quot);
1367
1368         umcon = rd_regl(port, S3C2410_UMCON);
1369         if (termios->c_cflag & CRTSCTS) {
1370                 umcon |= S3C2410_UMCOM_AFC;
1371                 /* Disable RTS when RX FIFO contains 63 bytes */
1372                 umcon &= ~S3C2412_UMCON_AFC_8;
1373         } else {
1374                 umcon &= ~S3C2410_UMCOM_AFC;
1375         }
1376         wr_regl(port, S3C2410_UMCON, umcon);
1377
1378         if (ourport->info->has_divslot)
1379                 wr_regl(port, S3C2443_DIVSLOT, udivslot);
1380
1381         dbg("uart: ulcon = 0x%08x, ucon = 0x%08x, ufcon = 0x%08x\n",
1382             rd_regl(port, S3C2410_ULCON),
1383             rd_regl(port, S3C2410_UCON),
1384             rd_regl(port, S3C2410_UFCON));
1385
1386         /*
1387          * Update the per-port timeout.
1388          */
1389         uart_update_timeout(port, termios->c_cflag, baud);
1390
1391         /*
1392          * Which character status flags are we interested in?
1393          */
1394         port->read_status_mask = S3C2410_UERSTAT_OVERRUN;
1395         if (termios->c_iflag & INPCK)
1396                 port->read_status_mask |= S3C2410_UERSTAT_FRAME |
1397                         S3C2410_UERSTAT_PARITY;
1398         /*
1399          * Which character status flags should we ignore?
1400          */
1401         port->ignore_status_mask = 0;
1402         if (termios->c_iflag & IGNPAR)
1403                 port->ignore_status_mask |= S3C2410_UERSTAT_OVERRUN;
1404         if (termios->c_iflag & IGNBRK && termios->c_iflag & IGNPAR)
1405                 port->ignore_status_mask |= S3C2410_UERSTAT_FRAME;
1406
1407         /*
1408          * Ignore all characters if CREAD is not set.
1409          */
1410         if ((termios->c_cflag & CREAD) == 0)
1411                 port->ignore_status_mask |= RXSTAT_DUMMY_READ;
1412
1413         spin_unlock_irqrestore(&port->lock, flags);
1414 }
1415
1416 static const char *s3c24xx_serial_type(struct uart_port *port)
1417 {
1418         switch (port->type) {
1419         case PORT_S3C2410:
1420                 return "S3C2410";
1421         case PORT_S3C2440:
1422                 return "S3C2440";
1423         case PORT_S3C2412:
1424                 return "S3C2412";
1425         case PORT_S3C6400:
1426                 return "S3C6400/10";
1427         default:
1428                 return NULL;
1429         }
1430 }
1431
1432 #define MAP_SIZE (0x100)
1433
1434 static void s3c24xx_serial_release_port(struct uart_port *port)
1435 {
1436         release_mem_region(port->mapbase, MAP_SIZE);
1437 }
1438
1439 static int s3c24xx_serial_request_port(struct uart_port *port)
1440 {
1441         const char *name = s3c24xx_serial_portname(port);
1442         return request_mem_region(port->mapbase, MAP_SIZE, name) ? 0 : -EBUSY;
1443 }
1444
1445 static void s3c24xx_serial_config_port(struct uart_port *port, int flags)
1446 {
1447         struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1448
1449         if (flags & UART_CONFIG_TYPE &&
1450             s3c24xx_serial_request_port(port) == 0)
1451                 port->type = info->type;
1452 }
1453
1454 /*
1455  * verify the new serial_struct (for TIOCSSERIAL).
1456  */
1457 static int
1458 s3c24xx_serial_verify_port(struct uart_port *port, struct serial_struct *ser)
1459 {
1460         struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1461
1462         if (ser->type != PORT_UNKNOWN && ser->type != info->type)
1463                 return -EINVAL;
1464
1465         return 0;
1466 }
1467
1468
1469 #ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
1470
1471 static struct console s3c24xx_serial_console;
1472
1473 static int __init s3c24xx_serial_console_init(void)
1474 {
1475         register_console(&s3c24xx_serial_console);
1476         return 0;
1477 }
1478 console_initcall(s3c24xx_serial_console_init);
1479
1480 #define S3C24XX_SERIAL_CONSOLE &s3c24xx_serial_console
1481 #else
1482 #define S3C24XX_SERIAL_CONSOLE NULL
1483 #endif
1484
1485 #if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL)
1486 static int s3c24xx_serial_get_poll_char(struct uart_port *port);
1487 static void s3c24xx_serial_put_poll_char(struct uart_port *port,
1488                          unsigned char c);
1489 #endif
1490
1491 static struct uart_ops s3c24xx_serial_ops = {
1492         .pm             = s3c24xx_serial_pm,
1493         .tx_empty       = s3c24xx_serial_tx_empty,
1494         .get_mctrl      = s3c24xx_serial_get_mctrl,
1495         .set_mctrl      = s3c24xx_serial_set_mctrl,
1496         .stop_tx        = s3c24xx_serial_stop_tx,
1497         .start_tx       = s3c24xx_serial_start_tx,
1498         .stop_rx        = s3c24xx_serial_stop_rx,
1499         .break_ctl      = s3c24xx_serial_break_ctl,
1500         .startup        = s3c24xx_serial_startup,
1501         .shutdown       = s3c24xx_serial_shutdown,
1502         .set_termios    = s3c24xx_serial_set_termios,
1503         .type           = s3c24xx_serial_type,
1504         .release_port   = s3c24xx_serial_release_port,
1505         .request_port   = s3c24xx_serial_request_port,
1506         .config_port    = s3c24xx_serial_config_port,
1507         .verify_port    = s3c24xx_serial_verify_port,
1508 #if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL)
1509         .poll_get_char = s3c24xx_serial_get_poll_char,
1510         .poll_put_char = s3c24xx_serial_put_poll_char,
1511 #endif
1512 };
1513
1514 static struct uart_driver s3c24xx_uart_drv = {
1515         .owner          = THIS_MODULE,
1516         .driver_name    = "s3c2410_serial",
1517         .nr             = CONFIG_SERIAL_SAMSUNG_UARTS,
1518         .cons           = S3C24XX_SERIAL_CONSOLE,
1519         .dev_name       = S3C24XX_SERIAL_NAME,
1520         .major          = S3C24XX_SERIAL_MAJOR,
1521         .minor          = S3C24XX_SERIAL_MINOR,
1522 };
1523
1524 #define __PORT_LOCK_UNLOCKED(i) \
1525         __SPIN_LOCK_UNLOCKED(s3c24xx_serial_ports[i].port.lock)
1526 static struct s3c24xx_uart_port
1527 s3c24xx_serial_ports[CONFIG_SERIAL_SAMSUNG_UARTS] = {
1528         [0] = {
1529                 .port = {
1530                         .lock           = __PORT_LOCK_UNLOCKED(0),
1531                         .iotype         = UPIO_MEM,
1532                         .uartclk        = 0,
1533                         .fifosize       = 16,
1534                         .ops            = &s3c24xx_serial_ops,
1535                         .flags          = UPF_BOOT_AUTOCONF,
1536                         .line           = 0,
1537                 }
1538         },
1539         [1] = {
1540                 .port = {
1541                         .lock           = __PORT_LOCK_UNLOCKED(1),
1542                         .iotype         = UPIO_MEM,
1543                         .uartclk        = 0,
1544                         .fifosize       = 16,
1545                         .ops            = &s3c24xx_serial_ops,
1546                         .flags          = UPF_BOOT_AUTOCONF,
1547                         .line           = 1,
1548                 }
1549         },
1550 #if CONFIG_SERIAL_SAMSUNG_UARTS > 2
1551
1552         [2] = {
1553                 .port = {
1554                         .lock           = __PORT_LOCK_UNLOCKED(2),
1555                         .iotype         = UPIO_MEM,
1556                         .uartclk        = 0,
1557                         .fifosize       = 16,
1558                         .ops            = &s3c24xx_serial_ops,
1559                         .flags          = UPF_BOOT_AUTOCONF,
1560                         .line           = 2,
1561                 }
1562         },
1563 #endif
1564 #if CONFIG_SERIAL_SAMSUNG_UARTS > 3
1565         [3] = {
1566                 .port = {
1567                         .lock           = __PORT_LOCK_UNLOCKED(3),
1568                         .iotype         = UPIO_MEM,
1569                         .uartclk        = 0,
1570                         .fifosize       = 16,
1571                         .ops            = &s3c24xx_serial_ops,
1572                         .flags          = UPF_BOOT_AUTOCONF,
1573                         .line           = 3,
1574                 }
1575         }
1576 #endif
1577 };
1578 #undef __PORT_LOCK_UNLOCKED
1579
1580 /* s3c24xx_serial_resetport
1581  *
1582  * reset the fifos and other the settings.
1583 */
1584
1585 static void s3c24xx_serial_resetport(struct uart_port *port,
1586                                    struct s3c2410_uartcfg *cfg)
1587 {
1588         struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1589         unsigned long ucon = rd_regl(port, S3C2410_UCON);
1590         unsigned int ucon_mask;
1591
1592         ucon_mask = info->clksel_mask;
1593         if (info->type == PORT_S3C2440)
1594                 ucon_mask |= S3C2440_UCON0_DIVMASK;
1595
1596         ucon &= ucon_mask;
1597         wr_regl(port, S3C2410_UCON,  ucon | cfg->ucon);
1598
1599         /* reset both fifos */
1600         wr_regl(port, S3C2410_UFCON, cfg->ufcon | S3C2410_UFCON_RESETBOTH);
1601         wr_regl(port, S3C2410_UFCON, cfg->ufcon);
1602
1603         /* some delay is required after fifo reset */
1604         udelay(1);
1605 }
1606
1607
1608 #ifdef CONFIG_ARM_S3C24XX_CPUFREQ
1609
1610 static int s3c24xx_serial_cpufreq_transition(struct notifier_block *nb,
1611                                              unsigned long val, void *data)
1612 {
1613         struct s3c24xx_uart_port *port;
1614         struct uart_port *uport;
1615
1616         port = container_of(nb, struct s3c24xx_uart_port, freq_transition);
1617         uport = &port->port;
1618
1619         /* check to see if port is enabled */
1620
1621         if (port->pm_level != 0)
1622                 return 0;
1623
1624         /* try and work out if the baudrate is changing, we can detect
1625          * a change in rate, but we do not have support for detecting
1626          * a disturbance in the clock-rate over the change.
1627          */
1628
1629         if (IS_ERR(port->baudclk))
1630                 goto exit;
1631
1632         if (port->baudclk_rate == clk_get_rate(port->baudclk))
1633                 goto exit;
1634
1635         if (val == CPUFREQ_PRECHANGE) {
1636                 /* we should really shut the port down whilst the
1637                  * frequency change is in progress. */
1638
1639         } else if (val == CPUFREQ_POSTCHANGE) {
1640                 struct ktermios *termios;
1641                 struct tty_struct *tty;
1642
1643                 if (uport->state == NULL)
1644                         goto exit;
1645
1646                 tty = uport->state->port.tty;
1647
1648                 if (tty == NULL)
1649                         goto exit;
1650
1651                 termios = &tty->termios;
1652
1653                 if (termios == NULL) {
1654                         dev_warn(uport->dev, "%s: no termios?\n", __func__);
1655                         goto exit;
1656                 }
1657
1658                 s3c24xx_serial_set_termios(uport, termios, NULL);
1659         }
1660
1661 exit:
1662         return 0;
1663 }
1664
1665 static inline int
1666 s3c24xx_serial_cpufreq_register(struct s3c24xx_uart_port *port)
1667 {
1668         port->freq_transition.notifier_call = s3c24xx_serial_cpufreq_transition;
1669
1670         return cpufreq_register_notifier(&port->freq_transition,
1671                                          CPUFREQ_TRANSITION_NOTIFIER);
1672 }
1673
1674 static inline void
1675 s3c24xx_serial_cpufreq_deregister(struct s3c24xx_uart_port *port)
1676 {
1677         cpufreq_unregister_notifier(&port->freq_transition,
1678                                     CPUFREQ_TRANSITION_NOTIFIER);
1679 }
1680
1681 #else
1682 static inline int
1683 s3c24xx_serial_cpufreq_register(struct s3c24xx_uart_port *port)
1684 {
1685         return 0;
1686 }
1687
1688 static inline void
1689 s3c24xx_serial_cpufreq_deregister(struct s3c24xx_uart_port *port)
1690 {
1691 }
1692 #endif
1693
1694 /* s3c24xx_serial_init_port
1695  *
1696  * initialise a single serial port from the platform device given
1697  */
1698
1699 static int s3c24xx_serial_init_port(struct s3c24xx_uart_port *ourport,
1700                                     struct platform_device *platdev)
1701 {
1702         struct uart_port *port = &ourport->port;
1703         struct s3c2410_uartcfg *cfg = ourport->cfg;
1704         struct resource *res;
1705         int ret;
1706
1707         dbg("s3c24xx_serial_init_port: port=%p, platdev=%p\n", port, platdev);
1708
1709         if (platdev == NULL)
1710                 return -ENODEV;
1711
1712         if (port->mapbase != 0)
1713                 return -EINVAL;
1714
1715         /* setup info for port */
1716         port->dev       = &platdev->dev;
1717
1718         /* Startup sequence is different for s3c64xx and higher SoC's */
1719         if (s3c24xx_serial_has_interrupt_mask(port))
1720                 s3c24xx_serial_ops.startup = s3c64xx_serial_startup;
1721
1722         port->uartclk = 1;
1723
1724         if (cfg->uart_flags & UPF_CONS_FLOW) {
1725                 dbg("s3c24xx_serial_init_port: enabling flow control\n");
1726                 port->flags |= UPF_CONS_FLOW;
1727         }
1728
1729         /* sort our the physical and virtual addresses for each UART */
1730
1731         res = platform_get_resource(platdev, IORESOURCE_MEM, 0);
1732         if (res == NULL) {
1733                 dev_err(port->dev, "failed to find memory resource for uart\n");
1734                 return -EINVAL;
1735         }
1736
1737         dbg("resource %pR)\n", res);
1738
1739         port->membase = devm_ioremap(port->dev, res->start, resource_size(res));
1740         if (!port->membase) {
1741                 dev_err(port->dev, "failed to remap controller address\n");
1742                 return -EBUSY;
1743         }
1744
1745         port->mapbase = res->start;
1746         ret = platform_get_irq(platdev, 0);
1747         if (ret < 0)
1748                 port->irq = 0;
1749         else {
1750                 port->irq = ret;
1751                 ourport->rx_irq = ret;
1752                 ourport->tx_irq = ret + 1;
1753         }
1754
1755         ret = platform_get_irq(platdev, 1);
1756         if (ret > 0)
1757                 ourport->tx_irq = ret;
1758         /*
1759          * DMA is currently supported only on DT platforms, if DMA properties
1760          * are specified.
1761          */
1762         if (platdev->dev.of_node && of_find_property(platdev->dev.of_node,
1763                                                      "dmas", NULL)) {
1764                 ourport->dma = devm_kzalloc(port->dev,
1765                                             sizeof(*ourport->dma),
1766                                             GFP_KERNEL);
1767                 if (!ourport->dma) {
1768                         ret = -ENOMEM;
1769                         goto err;
1770                 }
1771         }
1772
1773         ourport->clk    = clk_get(&platdev->dev, "uart");
1774         if (IS_ERR(ourport->clk)) {
1775                 pr_err("%s: Controller clock not found\n",
1776                                 dev_name(&platdev->dev));
1777                 ret = PTR_ERR(ourport->clk);
1778                 goto err;
1779         }
1780
1781         ret = clk_prepare_enable(ourport->clk);
1782         if (ret) {
1783                 pr_err("uart: clock failed to prepare+enable: %d\n", ret);
1784                 clk_put(ourport->clk);
1785                 goto err;
1786         }
1787
1788         /* Keep all interrupts masked and cleared */
1789         if (s3c24xx_serial_has_interrupt_mask(port)) {
1790                 wr_regl(port, S3C64XX_UINTM, 0xf);
1791                 wr_regl(port, S3C64XX_UINTP, 0xf);
1792                 wr_regl(port, S3C64XX_UINTSP, 0xf);
1793         }
1794
1795         dbg("port: map=%pa, mem=%p, irq=%d (%d,%d), clock=%u\n",
1796             &port->mapbase, port->membase, port->irq,
1797             ourport->rx_irq, ourport->tx_irq, port->uartclk);
1798
1799         /* reset the fifos (and setup the uart) */
1800         s3c24xx_serial_resetport(port, cfg);
1801
1802         return 0;
1803
1804 err:
1805         port->mapbase = 0;
1806         return ret;
1807 }
1808
1809 /* Device driver serial port probe */
1810
1811 static const struct of_device_id s3c24xx_uart_dt_match[];
1812 static int probe_index;
1813
1814 static inline struct s3c24xx_serial_drv_data *s3c24xx_get_driver_data(
1815                         struct platform_device *pdev)
1816 {
1817 #ifdef CONFIG_OF
1818         if (pdev->dev.of_node) {
1819                 const struct of_device_id *match;
1820                 match = of_match_node(s3c24xx_uart_dt_match, pdev->dev.of_node);
1821                 return (struct s3c24xx_serial_drv_data *)match->data;
1822         }
1823 #endif
1824         return (struct s3c24xx_serial_drv_data *)
1825                         platform_get_device_id(pdev)->driver_data;
1826 }
1827
1828 static int s3c24xx_serial_probe(struct platform_device *pdev)
1829 {
1830         struct device_node *np = pdev->dev.of_node;
1831         struct s3c24xx_uart_port *ourport;
1832         int index = probe_index;
1833         int ret;
1834
1835         if (np) {
1836                 ret = of_alias_get_id(np, "serial");
1837                 if (ret >= 0)
1838                         index = ret;
1839         }
1840
1841         dbg("s3c24xx_serial_probe(%p) %d\n", pdev, index);
1842
1843         if (index >= ARRAY_SIZE(s3c24xx_serial_ports)) {
1844                 dev_err(&pdev->dev, "serial%d out of range\n", index);
1845                 return -EINVAL;
1846         }
1847         ourport = &s3c24xx_serial_ports[index];
1848
1849         ourport->drv_data = s3c24xx_get_driver_data(pdev);
1850         if (!ourport->drv_data) {
1851                 dev_err(&pdev->dev, "could not find driver data\n");
1852                 return -ENODEV;
1853         }
1854
1855         ourport->baudclk = ERR_PTR(-EINVAL);
1856         ourport->info = ourport->drv_data->info;
1857         ourport->cfg = (dev_get_platdata(&pdev->dev)) ?
1858                         dev_get_platdata(&pdev->dev) :
1859                         ourport->drv_data->def_cfg;
1860
1861         if (np)
1862                 of_property_read_u32(np,
1863                         "samsung,uart-fifosize", &ourport->port.fifosize);
1864
1865         if (ourport->drv_data->fifosize[index])
1866                 ourport->port.fifosize = ourport->drv_data->fifosize[index];
1867         else if (ourport->info->fifosize)
1868                 ourport->port.fifosize = ourport->info->fifosize;
1869
1870         /*
1871          * DMA transfers must be aligned at least to cache line size,
1872          * so find minimal transfer size suitable for DMA mode
1873          */
1874         ourport->min_dma_size = max_t(int, ourport->port.fifosize,
1875                                     dma_get_cache_alignment());
1876
1877         dbg("%s: initialising port %p...\n", __func__, ourport);
1878
1879         ret = s3c24xx_serial_init_port(ourport, pdev);
1880         if (ret < 0)
1881                 return ret;
1882
1883         if (!s3c24xx_uart_drv.state) {
1884                 ret = uart_register_driver(&s3c24xx_uart_drv);
1885                 if (ret < 0) {
1886                         pr_err("Failed to register Samsung UART driver\n");
1887                         return ret;
1888                 }
1889         }
1890
1891         dbg("%s: adding port\n", __func__);
1892         uart_add_one_port(&s3c24xx_uart_drv, &ourport->port);
1893         platform_set_drvdata(pdev, &ourport->port);
1894
1895         /*
1896          * Deactivate the clock enabled in s3c24xx_serial_init_port here,
1897          * so that a potential re-enablement through the pm-callback overlaps
1898          * and keeps the clock enabled in this case.
1899          */
1900         clk_disable_unprepare(ourport->clk);
1901
1902         ret = s3c24xx_serial_cpufreq_register(ourport);
1903         if (ret < 0)
1904                 dev_err(&pdev->dev, "failed to add cpufreq notifier\n");
1905
1906         probe_index++;
1907
1908         return 0;
1909 }
1910
1911 static int s3c24xx_serial_remove(struct platform_device *dev)
1912 {
1913         struct uart_port *port = s3c24xx_dev_to_port(&dev->dev);
1914
1915         if (port) {
1916                 s3c24xx_serial_cpufreq_deregister(to_ourport(port));
1917                 uart_remove_one_port(&s3c24xx_uart_drv, port);
1918         }
1919
1920         uart_unregister_driver(&s3c24xx_uart_drv);
1921
1922         return 0;
1923 }
1924
1925 /* UART power management code */
1926 #ifdef CONFIG_PM_SLEEP
1927 static int s3c24xx_serial_suspend(struct device *dev)
1928 {
1929         struct uart_port *port = s3c24xx_dev_to_port(dev);
1930
1931         if (port)
1932                 uart_suspend_port(&s3c24xx_uart_drv, port);
1933
1934         return 0;
1935 }
1936
1937 static int s3c24xx_serial_resume(struct device *dev)
1938 {
1939         struct uart_port *port = s3c24xx_dev_to_port(dev);
1940         struct s3c24xx_uart_port *ourport = to_ourport(port);
1941
1942         if (port) {
1943                 clk_prepare_enable(ourport->clk);
1944                 s3c24xx_serial_resetport(port, s3c24xx_port_to_cfg(port));
1945                 clk_disable_unprepare(ourport->clk);
1946
1947                 uart_resume_port(&s3c24xx_uart_drv, port);
1948         }
1949
1950         return 0;
1951 }
1952
1953 static int s3c24xx_serial_resume_noirq(struct device *dev)
1954 {
1955         struct uart_port *port = s3c24xx_dev_to_port(dev);
1956         struct s3c24xx_uart_port *ourport = to_ourport(port);
1957
1958         if (port) {
1959                 /* restore IRQ mask */
1960                 if (s3c24xx_serial_has_interrupt_mask(port)) {
1961                         unsigned int uintm = 0xf;
1962                         if (tx_enabled(port))
1963                                 uintm &= ~S3C64XX_UINTM_TXD_MSK;
1964                         if (rx_enabled(port))
1965                                 uintm &= ~S3C64XX_UINTM_RXD_MSK;
1966                         clk_prepare_enable(ourport->clk);
1967                         wr_regl(port, S3C64XX_UINTM, uintm);
1968                         clk_disable_unprepare(ourport->clk);
1969                 }
1970         }
1971
1972         return 0;
1973 }
1974
1975 static const struct dev_pm_ops s3c24xx_serial_pm_ops = {
1976         .suspend = s3c24xx_serial_suspend,
1977         .resume = s3c24xx_serial_resume,
1978         .resume_noirq = s3c24xx_serial_resume_noirq,
1979 };
1980 #define SERIAL_SAMSUNG_PM_OPS   (&s3c24xx_serial_pm_ops)
1981
1982 #else /* !CONFIG_PM_SLEEP */
1983
1984 #define SERIAL_SAMSUNG_PM_OPS   NULL
1985 #endif /* CONFIG_PM_SLEEP */
1986
1987 /* Console code */
1988
1989 #ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
1990
1991 static struct uart_port *cons_uart;
1992
1993 static int
1994 s3c24xx_serial_console_txrdy(struct uart_port *port, unsigned int ufcon)
1995 {
1996         struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1997         unsigned long ufstat, utrstat;
1998
1999         if (ufcon & S3C2410_UFCON_FIFOMODE) {
2000                 /* fifo mode - check amount of data in fifo registers... */
2001
2002                 ufstat = rd_regl(port, S3C2410_UFSTAT);
2003                 return (ufstat & info->tx_fifofull) ? 0 : 1;
2004         }
2005
2006         /* in non-fifo mode, we go and use the tx buffer empty */
2007
2008         utrstat = rd_regl(port, S3C2410_UTRSTAT);
2009         return (utrstat & S3C2410_UTRSTAT_TXE) ? 1 : 0;
2010 }
2011
2012 static bool
2013 s3c24xx_port_configured(unsigned int ucon)
2014 {
2015         /* consider the serial port configured if the tx/rx mode set */
2016         return (ucon & 0xf) != 0;
2017 }
2018
2019 #ifdef CONFIG_CONSOLE_POLL
2020 /*
2021  * Console polling routines for writing and reading from the uart while
2022  * in an interrupt or debug context.
2023  */
2024
2025 static int s3c24xx_serial_get_poll_char(struct uart_port *port)
2026 {
2027         struct s3c24xx_uart_port *ourport = to_ourport(port);
2028         unsigned int ufstat;
2029
2030         ufstat = rd_regl(port, S3C2410_UFSTAT);
2031         if (s3c24xx_serial_rx_fifocnt(ourport, ufstat) == 0)
2032                 return NO_POLL_CHAR;
2033
2034         return rd_regb(port, S3C2410_URXH);
2035 }
2036
2037 static void s3c24xx_serial_put_poll_char(struct uart_port *port,
2038                 unsigned char c)
2039 {
2040         unsigned int ufcon = rd_regl(port, S3C2410_UFCON);
2041         unsigned int ucon = rd_regl(port, S3C2410_UCON);
2042
2043         /* not possible to xmit on unconfigured port */
2044         if (!s3c24xx_port_configured(ucon))
2045                 return;
2046
2047         while (!s3c24xx_serial_console_txrdy(port, ufcon))
2048                 cpu_relax();
2049         wr_regb(port, S3C2410_UTXH, c);
2050 }
2051
2052 #endif /* CONFIG_CONSOLE_POLL */
2053
2054 static void
2055 s3c24xx_serial_console_putchar(struct uart_port *port, int ch)
2056 {
2057         unsigned int ufcon = rd_regl(port, S3C2410_UFCON);
2058
2059         while (!s3c24xx_serial_console_txrdy(port, ufcon))
2060                 cpu_relax();
2061         wr_regb(port, S3C2410_UTXH, ch);
2062 }
2063
2064 static void
2065 s3c24xx_serial_console_write(struct console *co, const char *s,
2066                              unsigned int count)
2067 {
2068         unsigned int ucon = rd_regl(cons_uart, S3C2410_UCON);
2069
2070         /* not possible to xmit on unconfigured port */
2071         if (!s3c24xx_port_configured(ucon))
2072                 return;
2073
2074         uart_console_write(cons_uart, s, count, s3c24xx_serial_console_putchar);
2075 }
2076
2077 static void __init
2078 s3c24xx_serial_get_options(struct uart_port *port, int *baud,
2079                            int *parity, int *bits)
2080 {
2081         struct clk *clk;
2082         unsigned int ulcon;
2083         unsigned int ucon;
2084         unsigned int ubrdiv;
2085         unsigned long rate;
2086         unsigned int clk_sel;
2087         char clk_name[MAX_CLK_NAME_LENGTH];
2088
2089         ulcon  = rd_regl(port, S3C2410_ULCON);
2090         ucon   = rd_regl(port, S3C2410_UCON);
2091         ubrdiv = rd_regl(port, S3C2410_UBRDIV);
2092
2093         dbg("s3c24xx_serial_get_options: port=%p\n"
2094             "registers: ulcon=%08x, ucon=%08x, ubdriv=%08x\n",
2095             port, ulcon, ucon, ubrdiv);
2096
2097         if (s3c24xx_port_configured(ucon)) {
2098                 switch (ulcon & S3C2410_LCON_CSMASK) {
2099                 case S3C2410_LCON_CS5:
2100                         *bits = 5;
2101                         break;
2102                 case S3C2410_LCON_CS6:
2103                         *bits = 6;
2104                         break;
2105                 case S3C2410_LCON_CS7:
2106                         *bits = 7;
2107                         break;
2108                 case S3C2410_LCON_CS8:
2109                 default:
2110                         *bits = 8;
2111                         break;
2112                 }
2113
2114                 switch (ulcon & S3C2410_LCON_PMASK) {
2115                 case S3C2410_LCON_PEVEN:
2116                         *parity = 'e';
2117                         break;
2118
2119                 case S3C2410_LCON_PODD:
2120                         *parity = 'o';
2121                         break;
2122
2123                 case S3C2410_LCON_PNONE:
2124                 default:
2125                         *parity = 'n';
2126                 }
2127
2128                 /* now calculate the baud rate */
2129
2130                 clk_sel = s3c24xx_serial_getsource(port);
2131                 sprintf(clk_name, "clk_uart_baud%d", clk_sel);
2132
2133                 clk = clk_get(port->dev, clk_name);
2134                 if (!IS_ERR(clk))
2135                         rate = clk_get_rate(clk);
2136                 else
2137                         rate = 1;
2138
2139                 *baud = rate / (16 * (ubrdiv + 1));
2140                 dbg("calculated baud %d\n", *baud);
2141         }
2142
2143 }
2144
2145 static int __init
2146 s3c24xx_serial_console_setup(struct console *co, char *options)
2147 {
2148         struct uart_port *port;
2149         int baud = 9600;
2150         int bits = 8;
2151         int parity = 'n';
2152         int flow = 'n';
2153
2154         dbg("s3c24xx_serial_console_setup: co=%p (%d), %s\n",
2155             co, co->index, options);
2156
2157         /* is this a valid port */
2158
2159         if (co->index == -1 || co->index >= CONFIG_SERIAL_SAMSUNG_UARTS)
2160                 co->index = 0;
2161
2162         port = &s3c24xx_serial_ports[co->index].port;
2163
2164         /* is the port configured? */
2165
2166         if (port->mapbase == 0x0)
2167                 return -ENODEV;
2168
2169         cons_uart = port;
2170
2171         dbg("s3c24xx_serial_console_setup: port=%p (%d)\n", port, co->index);
2172
2173         /*
2174          * Check whether an invalid uart number has been specified, and
2175          * if so, search for the first available port that does have
2176          * console support.
2177          */
2178         if (options)
2179                 uart_parse_options(options, &baud, &parity, &bits, &flow);
2180         else
2181                 s3c24xx_serial_get_options(port, &baud, &parity, &bits);
2182
2183         dbg("s3c24xx_serial_console_setup: baud %d\n", baud);
2184
2185         return uart_set_options(port, co, baud, parity, bits, flow);
2186 }
2187
2188 static struct console s3c24xx_serial_console = {
2189         .name           = S3C24XX_SERIAL_NAME,
2190         .device         = uart_console_device,
2191         .flags          = CON_PRINTBUFFER,
2192         .index          = -1,
2193         .write          = s3c24xx_serial_console_write,
2194         .setup          = s3c24xx_serial_console_setup,
2195         .data           = &s3c24xx_uart_drv,
2196 };
2197 #endif /* CONFIG_SERIAL_SAMSUNG_CONSOLE */
2198
2199 #ifdef CONFIG_CPU_S3C2410
2200 static struct s3c24xx_serial_drv_data s3c2410_serial_drv_data = {
2201         .info = &(struct s3c24xx_uart_info) {
2202                 .name           = "Samsung S3C2410 UART",
2203                 .type           = PORT_S3C2410,
2204                 .fifosize       = 16,
2205                 .rx_fifomask    = S3C2410_UFSTAT_RXMASK,
2206                 .rx_fifoshift   = S3C2410_UFSTAT_RXSHIFT,
2207                 .rx_fifofull    = S3C2410_UFSTAT_RXFULL,
2208                 .tx_fifofull    = S3C2410_UFSTAT_TXFULL,
2209                 .tx_fifomask    = S3C2410_UFSTAT_TXMASK,
2210                 .tx_fifoshift   = S3C2410_UFSTAT_TXSHIFT,
2211                 .def_clk_sel    = S3C2410_UCON_CLKSEL0,
2212                 .num_clks       = 2,
2213                 .clksel_mask    = S3C2410_UCON_CLKMASK,
2214                 .clksel_shift   = S3C2410_UCON_CLKSHIFT,
2215         },
2216         .def_cfg = &(struct s3c2410_uartcfg) {
2217                 .ucon           = S3C2410_UCON_DEFAULT,
2218                 .ufcon          = S3C2410_UFCON_DEFAULT,
2219         },
2220 };
2221 #define S3C2410_SERIAL_DRV_DATA ((kernel_ulong_t)&s3c2410_serial_drv_data)
2222 #else
2223 #define S3C2410_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2224 #endif
2225
2226 #ifdef CONFIG_CPU_S3C2412
2227 static struct s3c24xx_serial_drv_data s3c2412_serial_drv_data = {
2228         .info = &(struct s3c24xx_uart_info) {
2229                 .name           = "Samsung S3C2412 UART",
2230                 .type           = PORT_S3C2412,
2231                 .fifosize       = 64,
2232                 .has_divslot    = 1,
2233                 .rx_fifomask    = S3C2440_UFSTAT_RXMASK,
2234                 .rx_fifoshift   = S3C2440_UFSTAT_RXSHIFT,
2235                 .rx_fifofull    = S3C2440_UFSTAT_RXFULL,
2236                 .tx_fifofull    = S3C2440_UFSTAT_TXFULL,
2237                 .tx_fifomask    = S3C2440_UFSTAT_TXMASK,
2238                 .tx_fifoshift   = S3C2440_UFSTAT_TXSHIFT,
2239                 .def_clk_sel    = S3C2410_UCON_CLKSEL2,
2240                 .num_clks       = 4,
2241                 .clksel_mask    = S3C2412_UCON_CLKMASK,
2242                 .clksel_shift   = S3C2412_UCON_CLKSHIFT,
2243         },
2244         .def_cfg = &(struct s3c2410_uartcfg) {
2245                 .ucon           = S3C2410_UCON_DEFAULT,
2246                 .ufcon          = S3C2410_UFCON_DEFAULT,
2247         },
2248 };
2249 #define S3C2412_SERIAL_DRV_DATA ((kernel_ulong_t)&s3c2412_serial_drv_data)
2250 #else
2251 #define S3C2412_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2252 #endif
2253
2254 #if defined(CONFIG_CPU_S3C2440) || defined(CONFIG_CPU_S3C2416) || \
2255         defined(CONFIG_CPU_S3C2443) || defined(CONFIG_CPU_S3C2442)
2256 static struct s3c24xx_serial_drv_data s3c2440_serial_drv_data = {
2257         .info = &(struct s3c24xx_uart_info) {
2258                 .name           = "Samsung S3C2440 UART",
2259                 .type           = PORT_S3C2440,
2260                 .fifosize       = 64,
2261                 .has_divslot    = 1,
2262                 .rx_fifomask    = S3C2440_UFSTAT_RXMASK,
2263                 .rx_fifoshift   = S3C2440_UFSTAT_RXSHIFT,
2264                 .rx_fifofull    = S3C2440_UFSTAT_RXFULL,
2265                 .tx_fifofull    = S3C2440_UFSTAT_TXFULL,
2266                 .tx_fifomask    = S3C2440_UFSTAT_TXMASK,
2267                 .tx_fifoshift   = S3C2440_UFSTAT_TXSHIFT,
2268                 .def_clk_sel    = S3C2410_UCON_CLKSEL2,
2269                 .num_clks       = 4,
2270                 .clksel_mask    = S3C2412_UCON_CLKMASK,
2271                 .clksel_shift   = S3C2412_UCON_CLKSHIFT,
2272         },
2273         .def_cfg = &(struct s3c2410_uartcfg) {
2274                 .ucon           = S3C2410_UCON_DEFAULT,
2275                 .ufcon          = S3C2410_UFCON_DEFAULT,
2276         },
2277 };
2278 #define S3C2440_SERIAL_DRV_DATA ((kernel_ulong_t)&s3c2440_serial_drv_data)
2279 #else
2280 #define S3C2440_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2281 #endif
2282
2283 #if defined(CONFIG_CPU_S3C6400) || defined(CONFIG_CPU_S3C6410)
2284 static struct s3c24xx_serial_drv_data s3c6400_serial_drv_data = {
2285         .info = &(struct s3c24xx_uart_info) {
2286                 .name           = "Samsung S3C6400 UART",
2287                 .type           = PORT_S3C6400,
2288                 .fifosize       = 64,
2289                 .has_divslot    = 1,
2290                 .rx_fifomask    = S3C2440_UFSTAT_RXMASK,
2291                 .rx_fifoshift   = S3C2440_UFSTAT_RXSHIFT,
2292                 .rx_fifofull    = S3C2440_UFSTAT_RXFULL,
2293                 .tx_fifofull    = S3C2440_UFSTAT_TXFULL,
2294                 .tx_fifomask    = S3C2440_UFSTAT_TXMASK,
2295                 .tx_fifoshift   = S3C2440_UFSTAT_TXSHIFT,
2296                 .def_clk_sel    = S3C2410_UCON_CLKSEL2,
2297                 .num_clks       = 4,
2298                 .clksel_mask    = S3C6400_UCON_CLKMASK,
2299                 .clksel_shift   = S3C6400_UCON_CLKSHIFT,
2300         },
2301         .def_cfg = &(struct s3c2410_uartcfg) {
2302                 .ucon           = S3C2410_UCON_DEFAULT,
2303                 .ufcon          = S3C2410_UFCON_DEFAULT,
2304         },
2305 };
2306 #define S3C6400_SERIAL_DRV_DATA ((kernel_ulong_t)&s3c6400_serial_drv_data)
2307 #else
2308 #define S3C6400_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2309 #endif
2310
2311 #ifdef CONFIG_CPU_S5PV210
2312 static struct s3c24xx_serial_drv_data s5pv210_serial_drv_data = {
2313         .info = &(struct s3c24xx_uart_info) {
2314                 .name           = "Samsung S5PV210 UART",
2315                 .type           = PORT_S3C6400,
2316                 .has_divslot    = 1,
2317                 .rx_fifomask    = S5PV210_UFSTAT_RXMASK,
2318                 .rx_fifoshift   = S5PV210_UFSTAT_RXSHIFT,
2319                 .rx_fifofull    = S5PV210_UFSTAT_RXFULL,
2320                 .tx_fifofull    = S5PV210_UFSTAT_TXFULL,
2321                 .tx_fifomask    = S5PV210_UFSTAT_TXMASK,
2322                 .tx_fifoshift   = S5PV210_UFSTAT_TXSHIFT,
2323                 .def_clk_sel    = S3C2410_UCON_CLKSEL0,
2324                 .num_clks       = 2,
2325                 .clksel_mask    = S5PV210_UCON_CLKMASK,
2326                 .clksel_shift   = S5PV210_UCON_CLKSHIFT,
2327         },
2328         .def_cfg = &(struct s3c2410_uartcfg) {
2329                 .ucon           = S5PV210_UCON_DEFAULT,
2330                 .ufcon          = S5PV210_UFCON_DEFAULT,
2331         },
2332         .fifosize = { 256, 64, 16, 16 },
2333 };
2334 #define S5PV210_SERIAL_DRV_DATA ((kernel_ulong_t)&s5pv210_serial_drv_data)
2335 #else
2336 #define S5PV210_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2337 #endif
2338
2339 #if defined(CONFIG_ARCH_EXYNOS)
2340 #define EXYNOS_COMMON_SERIAL_DRV_DATA                           \
2341         .info = &(struct s3c24xx_uart_info) {                   \
2342                 .name           = "Samsung Exynos UART",        \
2343                 .type           = PORT_S3C6400,                 \
2344                 .has_divslot    = 1,                            \
2345                 .rx_fifomask    = S5PV210_UFSTAT_RXMASK,        \
2346                 .rx_fifoshift   = S5PV210_UFSTAT_RXSHIFT,       \
2347                 .rx_fifofull    = S5PV210_UFSTAT_RXFULL,        \
2348                 .tx_fifofull    = S5PV210_UFSTAT_TXFULL,        \
2349                 .tx_fifomask    = S5PV210_UFSTAT_TXMASK,        \
2350                 .tx_fifoshift   = S5PV210_UFSTAT_TXSHIFT,       \
2351                 .def_clk_sel    = S3C2410_UCON_CLKSEL0,         \
2352                 .num_clks       = 1,                            \
2353                 .clksel_mask    = 0,                            \
2354                 .clksel_shift   = 0,                            \
2355         },                                                      \
2356         .def_cfg = &(struct s3c2410_uartcfg) {                  \
2357                 .ucon           = S5PV210_UCON_DEFAULT,         \
2358                 .ufcon          = S5PV210_UFCON_DEFAULT,        \
2359                 .has_fracval    = 1,                            \
2360         }                                                       \
2361
2362 static struct s3c24xx_serial_drv_data exynos4210_serial_drv_data = {
2363         EXYNOS_COMMON_SERIAL_DRV_DATA,
2364         .fifosize = { 256, 64, 16, 16 },
2365 };
2366
2367 static struct s3c24xx_serial_drv_data exynos5433_serial_drv_data = {
2368         EXYNOS_COMMON_SERIAL_DRV_DATA,
2369         .fifosize = { 64, 256, 16, 256 },
2370 };
2371
2372 #define EXYNOS4210_SERIAL_DRV_DATA ((kernel_ulong_t)&exynos4210_serial_drv_data)
2373 #define EXYNOS5433_SERIAL_DRV_DATA ((kernel_ulong_t)&exynos5433_serial_drv_data)
2374 #else
2375 #define EXYNOS4210_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2376 #define EXYNOS5433_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2377 #endif
2378
2379 static const struct platform_device_id s3c24xx_serial_driver_ids[] = {
2380         {
2381                 .name           = "s3c2410-uart",
2382                 .driver_data    = S3C2410_SERIAL_DRV_DATA,
2383         }, {
2384                 .name           = "s3c2412-uart",
2385                 .driver_data    = S3C2412_SERIAL_DRV_DATA,
2386         }, {
2387                 .name           = "s3c2440-uart",
2388                 .driver_data    = S3C2440_SERIAL_DRV_DATA,
2389         }, {
2390                 .name           = "s3c6400-uart",
2391                 .driver_data    = S3C6400_SERIAL_DRV_DATA,
2392         }, {
2393                 .name           = "s5pv210-uart",
2394                 .driver_data    = S5PV210_SERIAL_DRV_DATA,
2395         }, {
2396                 .name           = "exynos4210-uart",
2397                 .driver_data    = EXYNOS4210_SERIAL_DRV_DATA,
2398         }, {
2399                 .name           = "exynos5433-uart",
2400                 .driver_data    = EXYNOS5433_SERIAL_DRV_DATA,
2401         },
2402         { },
2403 };
2404 MODULE_DEVICE_TABLE(platform, s3c24xx_serial_driver_ids);
2405
2406 #ifdef CONFIG_OF
2407 static const struct of_device_id s3c24xx_uart_dt_match[] = {
2408         { .compatible = "samsung,s3c2410-uart",
2409                 .data = (void *)S3C2410_SERIAL_DRV_DATA },
2410         { .compatible = "samsung,s3c2412-uart",
2411                 .data = (void *)S3C2412_SERIAL_DRV_DATA },
2412         { .compatible = "samsung,s3c2440-uart",
2413                 .data = (void *)S3C2440_SERIAL_DRV_DATA },
2414         { .compatible = "samsung,s3c6400-uart",
2415                 .data = (void *)S3C6400_SERIAL_DRV_DATA },
2416         { .compatible = "samsung,s5pv210-uart",
2417                 .data = (void *)S5PV210_SERIAL_DRV_DATA },
2418         { .compatible = "samsung,exynos4210-uart",
2419                 .data = (void *)EXYNOS4210_SERIAL_DRV_DATA },
2420         { .compatible = "samsung,exynos5433-uart",
2421                 .data = (void *)EXYNOS5433_SERIAL_DRV_DATA },
2422         {},
2423 };
2424 MODULE_DEVICE_TABLE(of, s3c24xx_uart_dt_match);
2425 #endif
2426
2427 static struct platform_driver samsung_serial_driver = {
2428         .probe          = s3c24xx_serial_probe,
2429         .remove         = s3c24xx_serial_remove,
2430         .id_table       = s3c24xx_serial_driver_ids,
2431         .driver         = {
2432                 .name   = "samsung-uart",
2433                 .pm     = SERIAL_SAMSUNG_PM_OPS,
2434                 .of_match_table = of_match_ptr(s3c24xx_uart_dt_match),
2435         },
2436 };
2437
2438 module_platform_driver(samsung_serial_driver);
2439
2440 #ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
2441 /*
2442  * Early console.
2443  */
2444
2445 struct samsung_early_console_data {
2446         u32 txfull_mask;
2447 };
2448
2449 static void samsung_early_busyuart(struct uart_port *port)
2450 {
2451         while (!(readl(port->membase + S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXFE))
2452                 ;
2453 }
2454
2455 static void samsung_early_busyuart_fifo(struct uart_port *port)
2456 {
2457         struct samsung_early_console_data *data = port->private_data;
2458
2459         while (readl(port->membase + S3C2410_UFSTAT) & data->txfull_mask)
2460                 ;
2461 }
2462
2463 static void samsung_early_putc(struct uart_port *port, int c)
2464 {
2465         if (readl(port->membase + S3C2410_UFCON) & S3C2410_UFCON_FIFOMODE)
2466                 samsung_early_busyuart_fifo(port);
2467         else
2468                 samsung_early_busyuart(port);
2469
2470         writeb(c, port->membase + S3C2410_UTXH);
2471 }
2472
2473 static void samsung_early_write(struct console *con, const char *s, unsigned n)
2474 {
2475         struct earlycon_device *dev = con->data;
2476
2477         uart_console_write(&dev->port, s, n, samsung_early_putc);
2478 }
2479
2480 static int __init samsung_early_console_setup(struct earlycon_device *device,
2481                                               const char *opt)
2482 {
2483         if (!device->port.membase)
2484                 return -ENODEV;
2485
2486         device->con->write = samsung_early_write;
2487         return 0;
2488 }
2489
2490 /* S3C2410 */
2491 static struct samsung_early_console_data s3c2410_early_console_data = {
2492         .txfull_mask = S3C2410_UFSTAT_TXFULL,
2493 };
2494
2495 static int __init s3c2410_early_console_setup(struct earlycon_device *device,
2496                                               const char *opt)
2497 {
2498         device->port.private_data = &s3c2410_early_console_data;
2499         return samsung_early_console_setup(device, opt);
2500 }
2501 OF_EARLYCON_DECLARE(s3c2410, "samsung,s3c2410-uart",
2502                         s3c2410_early_console_setup);
2503
2504 /* S3C2412, S3C2440, S3C64xx */
2505 static struct samsung_early_console_data s3c2440_early_console_data = {
2506         .txfull_mask = S3C2440_UFSTAT_TXFULL,
2507 };
2508
2509 static int __init s3c2440_early_console_setup(struct earlycon_device *device,
2510                                               const char *opt)
2511 {
2512         device->port.private_data = &s3c2440_early_console_data;
2513         return samsung_early_console_setup(device, opt);
2514 }
2515 OF_EARLYCON_DECLARE(s3c2412, "samsung,s3c2412-uart",
2516                         s3c2440_early_console_setup);
2517 OF_EARLYCON_DECLARE(s3c2440, "samsung,s3c2440-uart",
2518                         s3c2440_early_console_setup);
2519 OF_EARLYCON_DECLARE(s3c6400, "samsung,s3c6400-uart",
2520                         s3c2440_early_console_setup);
2521
2522 /* S5PV210, EXYNOS */
2523 static struct samsung_early_console_data s5pv210_early_console_data = {
2524         .txfull_mask = S5PV210_UFSTAT_TXFULL,
2525 };
2526
2527 static int __init s5pv210_early_console_setup(struct earlycon_device *device,
2528                                               const char *opt)
2529 {
2530         device->port.private_data = &s5pv210_early_console_data;
2531         return samsung_early_console_setup(device, opt);
2532 }
2533 OF_EARLYCON_DECLARE(s5pv210, "samsung,s5pv210-uart",
2534                         s5pv210_early_console_setup);
2535 OF_EARLYCON_DECLARE(exynos4210, "samsung,exynos4210-uart",
2536                         s5pv210_early_console_setup);
2537 #endif
2538
2539 MODULE_ALIAS("platform:samsung-uart");
2540 MODULE_DESCRIPTION("Samsung SoC Serial port driver");
2541 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
2542 MODULE_LICENSE("GPL v2");