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Blackfin SPI driver: tweak spi cleanup function to match newer kernel changes
[linux-2.6-block.git] / drivers / spi / spi_bfin5xx.c
CommitLineData
a5f6abd4
WB		 1/*
2 * File: drivers/spi/bfin5xx_spi.c
3 * Based on: N/A
4 * Author: Luke Yang (Analog Devices Inc.)
5 *
6 * Created: March. 10th 2006
7 * Description: SPI controller driver for Blackfin 5xx
8 * Bugs: Enter bugs at http://blackfin.uclinux.org/
9 *
10 * Modified:
11 * March 10, 2006 bfin5xx_spi.c Created. (Luke Yang)
12 * August 7, 2006 added full duplex mode (Axel Weiss & Luke Yang)
13 *
14 * Copyright 2004-2006 Analog Devices Inc.
15 *
16 * This program is free software ; you can redistribute it and/or modify
17 * it under the terms of the GNU General Public License as published by
18 * the Free Software Foundation ; either version 2, or (at your option)
19 * any later version.
20 *
21 * This program is distributed in the hope that it will be useful,
22 * but WITHOUT ANY WARRANTY ; without even the implied warranty of
23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
24 * GNU General Public License for more details.
25 *
26 * You should have received a copy of the GNU General Public License
27 * along with this program ; see the file COPYING.
28 * If not, write to the Free Software Foundation,
29 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
30 */
31
32#include <linux/init.h>
33#include <linux/module.h>
34#include <linux/device.h>
35#include <linux/ioport.h>
36#include <linux/errno.h>
37#include <linux/interrupt.h>
38#include <linux/platform_device.h>
39#include <linux/dma-mapping.h>
40#include <linux/spi/spi.h>
41#include <linux/workqueue.h>
42#include <linux/errno.h>
43#include <linux/delay.h>
44
45#include <asm/io.h>
46#include <asm/irq.h>
47#include <asm/delay.h>
48#include <asm/dma.h>
49
50#include <asm/bfin5xx_spi.h>
51
52MODULE_AUTHOR("Luke Yang");
53MODULE_DESCRIPTION("Blackfin 5xx SPI Contoller");
54MODULE_LICENSE("GPL");
55
56#define IS_DMA_ALIGNED(x) (((u32)(x)&0x07)==0)
57
58#define DEFINE_SPI_REG(reg, off) \
59static inline u16 read_##reg(void) \
60 { return *(volatile unsigned short*)(SPI0_REGBASE + off); } \
61static inline void write_##reg(u16 v) \
62 {*(volatile unsigned short*)(SPI0_REGBASE + off) = v;\
63 SSYNC();}
64
65DEFINE_SPI_REG(CTRL, 0x00)
66DEFINE_SPI_REG(FLAG, 0x04)
67DEFINE_SPI_REG(STAT, 0x08)
68DEFINE_SPI_REG(TDBR, 0x0C)
69DEFINE_SPI_REG(RDBR, 0x10)
70DEFINE_SPI_REG(BAUD, 0x14)
71DEFINE_SPI_REG(SHAW, 0x18)
72#define START_STATE ((void*)0)
73#define RUNNING_STATE ((void*)1)
74#define DONE_STATE ((void*)2)
75#define ERROR_STATE ((void*)-1)
76#define QUEUE_RUNNING 0
77#define QUEUE_STOPPED 1
78int dma_requested;
79
80struct driver_data {
81 /* Driver model hookup */
82 struct platform_device *pdev;
83
84 /* SPI framework hookup */
85 struct spi_master *master;
86
87 /* BFIN hookup */
88 struct bfin5xx_spi_master *master_info;
89
90 /* Driver message queue */
91 struct workqueue_struct *workqueue;
92 struct work_struct pump_messages;
93 spinlock_t lock;
94 struct list_head queue;
95 int busy;
96 int run;
97
98 /* Message Transfer pump */
99 struct tasklet_struct pump_transfers;
100
101 /* Current message transfer state info */
102 struct spi_message *cur_msg;
103 struct spi_transfer *cur_transfer;
104 struct chip_data *cur_chip;
105 size_t len_in_bytes;
106 size_t len;
107 void *tx;
108 void *tx_end;
109 void *rx;
110 void *rx_end;
111 int dma_mapped;
112 dma_addr_t rx_dma;
113 dma_addr_t tx_dma;
114 size_t rx_map_len;
115 size_t tx_map_len;
116 u8 n_bytes;
117 void (*write) (struct driver_data *);
118 void (*read) (struct driver_data *);
119 void (*duplex) (struct driver_data *);
120};
121
122struct chip_data {
123 u16 ctl_reg;
124 u16 baud;
125 u16 flag;
126
127 u8 chip_select_num;
128 u8 n_bytes;
88b40369 129 u8 width; /* 0 or 1 */
a5f6abd4
WB		 130 u8 enable_dma;
131 u8 bits_per_word; /* 8 or 16 */
132 u8 cs_change_per_word;
133 u8 cs_chg_udelay;
134 void (*write) (struct driver_data *);
135 void (*read) (struct driver_data *);
136 void (*duplex) (struct driver_data *);
137};
138
88b40369 139static void bfin_spi_enable(struct driver_data *drv_data)
a5f6abd4
WB		 140{
141 u16 cr;
142
143 cr = read_CTRL();
144 write_CTRL(cr | BIT_CTL_ENABLE);
145 SSYNC();
146}
147
88b40369 148static void bfin_spi_disable(struct driver_data *drv_data)
a5f6abd4
WB		 149{
150 u16 cr;
151
152 cr = read_CTRL();
153 write_CTRL(cr & (~BIT_CTL_ENABLE));
154 SSYNC();
155}
156
157/* Caculate the SPI_BAUD register value based on input HZ */
158static u16 hz_to_spi_baud(u32 speed_hz)
159{
160 u_long sclk = get_sclk();
161 u16 spi_baud = (sclk / (2 * speed_hz));
162
163 if ((sclk % (2 * speed_hz)) > 0)
164 spi_baud++;
165
a5f6abd4
WB		 166 return spi_baud;
167}
168
169static int flush(struct driver_data *drv_data)
170{
171 unsigned long limit = loops_per_jiffy << 1;
172
173 /* wait for stop and clear stat */
174 while (!(read_STAT() & BIT_STAT_SPIF) && limit--)
175 continue;
176
177 write_STAT(BIT_STAT_CLR);
178
179 return limit;
180}
181
182/* stop controller and re-config current chip*/
183static void restore_state(struct driver_data *drv_data)
184{
185 struct chip_data *chip = drv_data->cur_chip;
186
187 /* Clear status and disable clock */
188 write_STAT(BIT_STAT_CLR);
189 bfin_spi_disable(drv_data);
88b40369 190 dev_dbg(&drv_data->pdev->dev, "restoring spi ctl state\n");
a5f6abd4
WB		 191
192#if defined(CONFIG_BF534) || defined(CONFIG_BF536) || defined(CONFIG_BF537)
88b40369
BW		 193 dev_dbg(&drv_data->pdev->dev,
194 "chip select number is %d\n", chip->chip_select_num);
195
a5f6abd4
WB		 196 switch (chip->chip_select_num) {
197 case 1:
198 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3c00);
199 SSYNC();
200 break;
201
202 case 2:
203 case 3:
204 bfin_write_PORT_MUX(bfin_read_PORT_MUX() | PJSE_SPI);
205 SSYNC();
206 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3800);
207 SSYNC();
208 break;
209
210 case 4:
211 bfin_write_PORT_MUX(bfin_read_PORT_MUX() | PFS4E_SPI);
212 SSYNC();
213 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3840);
214 SSYNC();
215 break;
216
217 case 5:
218 bfin_write_PORT_MUX(bfin_read_PORT_MUX() | PFS5E_SPI);
219 SSYNC();
220 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3820);
221 SSYNC();
222 break;
223
224 case 6:
225 bfin_write_PORT_MUX(bfin_read_PORT_MUX() | PFS6E_SPI);
226 SSYNC();
227 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3810);
228 SSYNC();
229 break;
230
231 case 7:
232 bfin_write_PORT_MUX(bfin_read_PORT_MUX() | PJCE_SPI);
233 SSYNC();
234 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3800);
235 SSYNC();
236 break;
237 }
238#endif
239
240 /* Load the registers */
241 write_CTRL(chip->ctl_reg);
242 write_BAUD(chip->baud);
243 write_FLAG(chip->flag);
244}
245
246/* used to kick off transfer in rx mode */
247static unsigned short dummy_read(void)
248{
249 unsigned short tmp;
250 tmp = read_RDBR();
251 return tmp;
252}
253
254static void null_writer(struct driver_data *drv_data)
255{
256 u8 n_bytes = drv_data->n_bytes;
257
258 while (drv_data->tx < drv_data->tx_end) {
259 write_TDBR(0);
260 while ((read_STAT() & BIT_STAT_TXS))
261 continue;
262 drv_data->tx += n_bytes;
263 }
264}
265
266static void null_reader(struct driver_data *drv_data)
267{
268 u8 n_bytes = drv_data->n_bytes;
269 dummy_read();
270
271 while (drv_data->rx < drv_data->rx_end) {
272 while (!(read_STAT() & BIT_STAT_RXS))
273 continue;
274 dummy_read();
275 drv_data->rx += n_bytes;
276 }
277}
278
279static void u8_writer(struct driver_data *drv_data)
280{
88b40369
BW		 281 dev_dbg(&drv_data->pdev->dev,
282 "cr8-s is 0x%x\n", read_STAT());
a5f6abd4
WB		 283 while (drv_data->tx < drv_data->tx_end) {
284 write_TDBR(*(u8 *) (drv_data->tx));
285 while (read_STAT() & BIT_STAT_TXS)
286 continue;
287 ++drv_data->tx;
288 }
289
290 /* poll for SPI completion before returning */
291 while (!(read_STAT() & BIT_STAT_SPIF))
292 continue;
293}
294
295static void u8_cs_chg_writer(struct driver_data *drv_data)
296{
297 struct chip_data *chip = drv_data->cur_chip;
298
299 while (drv_data->tx < drv_data->tx_end) {
300 write_FLAG(chip->flag);
301 SSYNC();
302
303 write_TDBR(*(u8 *) (drv_data->tx));
304 while (read_STAT() & BIT_STAT_TXS)
305 continue;
306 while (!(read_STAT() & BIT_STAT_SPIF))
307 continue;
308 write_FLAG(0xFF00 | chip->flag);
309 SSYNC();
310 if (chip->cs_chg_udelay)
311 udelay(chip->cs_chg_udelay);
312 ++drv_data->tx;
313 }
314 write_FLAG(0xFF00);
315 SSYNC();
316}
317
318static void u8_reader(struct driver_data *drv_data)
319{
88b40369
BW		 320 dev_dbg(&drv_data->pdev->dev,
321 "cr-8 is 0x%x\n", read_STAT());
a5f6abd4
WB		 322
323 /* clear TDBR buffer before read(else it will be shifted out) */
324 write_TDBR(0xFFFF);
325
326 dummy_read();
327
328 while (drv_data->rx < drv_data->rx_end - 1) {
329 while (!(read_STAT() & BIT_STAT_RXS))
330 continue;
331 *(u8 *) (drv_data->rx) = read_RDBR();
332 ++drv_data->rx;
333 }
334
335 while (!(read_STAT() & BIT_STAT_RXS))
336 continue;
337 *(u8 *) (drv_data->rx) = read_SHAW();
338 ++drv_data->rx;
339}
340
341static void u8_cs_chg_reader(struct driver_data *drv_data)
342{
343 struct chip_data *chip = drv_data->cur_chip;
344
345 while (drv_data->rx < drv_data->rx_end) {
346 write_FLAG(chip->flag);
347 SSYNC();
348
349 read_RDBR(); /* kick off */
350 while (!(read_STAT() & BIT_STAT_RXS))
351 continue;
352 while (!(read_STAT() & BIT_STAT_SPIF))
353 continue;
354 *(u8 *) (drv_data->rx) = read_SHAW();
355 write_FLAG(0xFF00 | chip->flag);
356 SSYNC();
357 if (chip->cs_chg_udelay)
358 udelay(chip->cs_chg_udelay);
359 ++drv_data->rx;
360 }
361 write_FLAG(0xFF00);
362 SSYNC();
363}
364
365static void u8_duplex(struct driver_data *drv_data)
366{
367 /* in duplex mode, clk is triggered by writing of TDBR */
368 while (drv_data->rx < drv_data->rx_end) {
369 write_TDBR(*(u8 *) (drv_data->tx));
370 while (!(read_STAT() & BIT_STAT_SPIF))
371 continue;
372 while (!(read_STAT() & BIT_STAT_RXS))
373 continue;
374 *(u8 *) (drv_data->rx) = read_RDBR();
375 ++drv_data->rx;
376 ++drv_data->tx;
377 }
378}
379
380static void u8_cs_chg_duplex(struct driver_data *drv_data)
381{
382 struct chip_data *chip = drv_data->cur_chip;
383
384 while (drv_data->rx < drv_data->rx_end) {
385 write_FLAG(chip->flag);
386 SSYNC();
387
388 write_TDBR(*(u8 *) (drv_data->tx));
389 while (!(read_STAT() & BIT_STAT_SPIF))
390 continue;
391 while (!(read_STAT() & BIT_STAT_RXS))
392 continue;
393 *(u8 *) (drv_data->rx) = read_RDBR();
394 write_FLAG(0xFF00 | chip->flag);
395 SSYNC();
396 if (chip->cs_chg_udelay)
397 udelay(chip->cs_chg_udelay);
398 ++drv_data->rx;
399 ++drv_data->tx;
400 }
401 write_FLAG(0xFF00);
402 SSYNC();
403}
404
405static void u16_writer(struct driver_data *drv_data)
406{
88b40369
BW		 407 dev_dbg(&drv_data->pdev->dev,
408 "cr16 is 0x%x\n", read_STAT());
409
a5f6abd4
WB		 410 while (drv_data->tx < drv_data->tx_end) {
411 write_TDBR(*(u16 *) (drv_data->tx));
412 while ((read_STAT() & BIT_STAT_TXS))
413 continue;
414 drv_data->tx += 2;
415 }
416
417 /* poll for SPI completion before returning */
418 while (!(read_STAT() & BIT_STAT_SPIF))
419 continue;
420}
421
422static void u16_cs_chg_writer(struct driver_data *drv_data)
423{
424 struct chip_data *chip = drv_data->cur_chip;
425
426 while (drv_data->tx < drv_data->tx_end) {
427 write_FLAG(chip->flag);
428 SSYNC();
429
430 write_TDBR(*(u16 *) (drv_data->tx));
431 while ((read_STAT() & BIT_STAT_TXS))
432 continue;
433 while (!(read_STAT() & BIT_STAT_SPIF))
434 continue;
435 write_FLAG(0xFF00 | chip->flag);
436 SSYNC();
437 if (chip->cs_chg_udelay)
438 udelay(chip->cs_chg_udelay);
439 drv_data->tx += 2;
440 }
441 write_FLAG(0xFF00);
442 SSYNC();
443}
444
445static void u16_reader(struct driver_data *drv_data)
446{
88b40369
BW		 447 dev_dbg(&drv_data->pdev->dev,
448 "cr-16 is 0x%x\n", read_STAT());
a5f6abd4
WB		 449 dummy_read();
450
451 while (drv_data->rx < (drv_data->rx_end - 2)) {
452 while (!(read_STAT() & BIT_STAT_RXS))
453 continue;
454 *(u16 *) (drv_data->rx) = read_RDBR();
455 drv_data->rx += 2;
456 }
457
458 while (!(read_STAT() & BIT_STAT_RXS))
459 continue;
460 *(u16 *) (drv_data->rx) = read_SHAW();
461 drv_data->rx += 2;
462}
463
464static void u16_cs_chg_reader(struct driver_data *drv_data)
465{
466 struct chip_data *chip = drv_data->cur_chip;
467
468 while (drv_data->rx < drv_data->rx_end) {
469 write_FLAG(chip->flag);
470 SSYNC();
471
472 read_RDBR(); /* kick off */
473 while (!(read_STAT() & BIT_STAT_RXS))
474 continue;
475 while (!(read_STAT() & BIT_STAT_SPIF))
476 continue;
477 *(u16 *) (drv_data->rx) = read_SHAW();
478 write_FLAG(0xFF00 | chip->flag);
479 SSYNC();
480 if (chip->cs_chg_udelay)
481 udelay(chip->cs_chg_udelay);
482 drv_data->rx += 2;
483 }
484 write_FLAG(0xFF00);
485 SSYNC();
486}
487
488static void u16_duplex(struct driver_data *drv_data)
489{
490 /* in duplex mode, clk is triggered by writing of TDBR */
491 while (drv_data->tx < drv_data->tx_end) {
492 write_TDBR(*(u16 *) (drv_data->tx));
493 while (!(read_STAT() & BIT_STAT_SPIF))
494 continue;
495 while (!(read_STAT() & BIT_STAT_RXS))
496 continue;
497 *(u16 *) (drv_data->rx) = read_RDBR();
498 drv_data->rx += 2;
499 drv_data->tx += 2;
500 }
501}
502
503static void u16_cs_chg_duplex(struct driver_data *drv_data)
504{
505 struct chip_data *chip = drv_data->cur_chip;
506
507 while (drv_data->tx < drv_data->tx_end) {
508 write_FLAG(chip->flag);
509 SSYNC();
510
511 write_TDBR(*(u16 *) (drv_data->tx));
512 while (!(read_STAT() & BIT_STAT_SPIF))
513 continue;
514 while (!(read_STAT() & BIT_STAT_RXS))
515 continue;
516 *(u16 *) (drv_data->rx) = read_RDBR();
517 write_FLAG(0xFF00 | chip->flag);
518 SSYNC();
519 if (chip->cs_chg_udelay)
520 udelay(chip->cs_chg_udelay);
521 drv_data->rx += 2;
522 drv_data->tx += 2;
523 }
524 write_FLAG(0xFF00);
525 SSYNC();
526}
527
528/* test if ther is more transfer to be done */
529static void *next_transfer(struct driver_data *drv_data)
530{
531 struct spi_message *msg = drv_data->cur_msg;
532 struct spi_transfer *trans = drv_data->cur_transfer;
533
534 /* Move to next transfer */
535 if (trans->transfer_list.next != &msg->transfers) {
536 drv_data->cur_transfer =
537 list_entry(trans->transfer_list.next,
538 struct spi_transfer, transfer_list);
539 return RUNNING_STATE;
540 } else
541 return DONE_STATE;
542}
543
544/*
545 * caller already set message->status;
546 * dma and pio irqs are blocked give finished message back
547 */
548static void giveback(struct driver_data *drv_data)
549{
550 struct spi_transfer *last_transfer;
551 unsigned long flags;
552 struct spi_message *msg;
553
554 spin_lock_irqsave(&drv_data->lock, flags);
555 msg = drv_data->cur_msg;
556 drv_data->cur_msg = NULL;
557 drv_data->cur_transfer = NULL;
558 drv_data->cur_chip = NULL;
559 queue_work(drv_data->workqueue, &drv_data->pump_messages);
560 spin_unlock_irqrestore(&drv_data->lock, flags);
561
562 last_transfer = list_entry(msg->transfers.prev,
563 struct spi_transfer, transfer_list);
564
565 msg->state = NULL;
566
567 /* disable chip select signal. And not stop spi in autobuffer mode */
568 if (drv_data->tx_dma != 0xFFFF) {
569 write_FLAG(0xFF00);
570 bfin_spi_disable(drv_data);
571 }
572
573 if (msg->complete)
574 msg->complete(msg->context);
575}
576
88b40369 577static irqreturn_t dma_irq_handler(int irq, void *dev_id)
a5f6abd4
WB		 578{
579 struct driver_data *drv_data = (struct driver_data *)dev_id;
580 struct spi_message *msg = drv_data->cur_msg;
581
88b40369 582 dev_dbg(&drv_data->pdev->dev, "in dma_irq_handler\n");
a5f6abd4
WB		 583 clear_dma_irqstat(CH_SPI);
584
585 /*
586 * wait for the last transaction shifted out. yes, these two
587 * while loops are supposed to be the same (see the HRM).
588 */
589 if (drv_data->tx != NULL) {
590 while (bfin_read_SPI_STAT() & TXS)
591 continue;
592 while (bfin_read_SPI_STAT() & TXS)
593 continue;
594 }
595
596 while (!(bfin_read_SPI_STAT() & SPIF))
597 continue;
598
599 bfin_spi_disable(drv_data);
600
601 msg->actual_length += drv_data->len_in_bytes;
602
603 /* Move to next transfer */
604 msg->state = next_transfer(drv_data);
605
606 /* Schedule transfer tasklet */
607 tasklet_schedule(&drv_data->pump_transfers);
608
609 /* free the irq handler before next transfer */
88b40369
BW		 610 dev_dbg(&drv_data->pdev->dev,
611 "disable dma channel irq%d\n",
612 CH_SPI);
a5f6abd4
WB		 613 dma_disable_irq(CH_SPI);
614
615 return IRQ_HANDLED;
616}
617
618static void pump_transfers(unsigned long data)
619{
620 struct driver_data *drv_data = (struct driver_data *)data;
621 struct spi_message *message = NULL;
622 struct spi_transfer *transfer = NULL;
623 struct spi_transfer *previous = NULL;
624 struct chip_data *chip = NULL;
88b40369
BW		 625 u8 width;
626 u16 cr, dma_width, dma_config;
a5f6abd4
WB		 627 u32 tranf_success = 1;
628
629 /* Get current state information */
630 message = drv_data->cur_msg;
631 transfer = drv_data->cur_transfer;
632 chip = drv_data->cur_chip;
633
634 /*
635 * if msg is error or done, report it back using complete() callback
636 */
637
638 /* Handle for abort */
639 if (message->state == ERROR_STATE) {
640 message->status = -EIO;
641 giveback(drv_data);
642 return;
643 }
644
645 /* Handle end of message */
646 if (message->state == DONE_STATE) {
647 message->status = 0;
648 giveback(drv_data);
649 return;
650 }
651
652 /* Delay if requested at end of transfer */
653 if (message->state == RUNNING_STATE) {
654 previous = list_entry(transfer->transfer_list.prev,
655 struct spi_transfer, transfer_list);
656 if (previous->delay_usecs)
657 udelay(previous->delay_usecs);
658 }
659
660 /* Setup the transfer state based on the type of transfer */
661 if (flush(drv_data) == 0) {
662 dev_err(&drv_data->pdev->dev, "pump_transfers: flush failed\n");
663 message->status = -EIO;
664 giveback(drv_data);
665 return;
666 }
667
668 if (transfer->tx_buf != NULL) {
669 drv_data->tx = (void *)transfer->tx_buf;
670 drv_data->tx_end = drv_data->tx + transfer->len;
88b40369
BW		 671 dev_dbg(&drv_data->pdev->dev, "tx_buf is %p, tx_end is %p\n",
672 transfer->tx_buf, drv_data->tx_end);
a5f6abd4
WB		 673 } else {
674 drv_data->tx = NULL;
675 }
676
677 if (transfer->rx_buf != NULL) {
678 drv_data->rx = transfer->rx_buf;
679 drv_data->rx_end = drv_data->rx + transfer->len;
88b40369
BW		 680 dev_dbg(&drv_data->pdev->dev, "rx_buf is %p, rx_end is %p\n",
681 transfer->rx_buf, drv_data->rx_end);
a5f6abd4
WB		 682 } else {
683 drv_data->rx = NULL;
684 }
685
686 drv_data->rx_dma = transfer->rx_dma;
687 drv_data->tx_dma = transfer->tx_dma;
688 drv_data->len_in_bytes = transfer->len;
689
690 width = chip->width;
691 if (width == CFG_SPI_WORDSIZE16) {
692 drv_data->len = (transfer->len) >> 1;
693 } else {
694 drv_data->len = transfer->len;
695 }
696 drv_data->write = drv_data->tx ? chip->write : null_writer;
697 drv_data->read = drv_data->rx ? chip->read : null_reader;
698 drv_data->duplex = chip->duplex ? chip->duplex : null_writer;
88b40369
BW		 699 dev_dbg(&drv_data->pdev->dev,
700 "transfer: drv_data->write is %p, chip->write is %p, null_wr is %p\n",
701 drv_data->write, chip->write, null_writer);
a5f6abd4
WB		 702
703 /* speed and width has been set on per message */
704 message->state = RUNNING_STATE;
705 dma_config = 0;
706
707 /* restore spi status for each spi transfer */
708 if (transfer->speed_hz) {
709 write_BAUD(hz_to_spi_baud(transfer->speed_hz));
710 } else {
711 write_BAUD(chip->baud);
712 }
713 write_FLAG(chip->flag);
714
88b40369
BW		 715 dev_dbg(&drv_data->pdev->dev,
716 "now pumping a transfer: width is %d, len is %d\n",
717 width, transfer->len);
a5f6abd4
WB		 718
719 /*
720 * Try to map dma buffer and do a dma transfer if
721 * successful use different way to r/w according to
722 * drv_data->cur_chip->enable_dma
723 */
724 if (drv_data->cur_chip->enable_dma && drv_data->len > 6) {
725
726 write_STAT(BIT_STAT_CLR);
727 disable_dma(CH_SPI);
728 clear_dma_irqstat(CH_SPI);
729 bfin_spi_disable(drv_data);
730
731 /* config dma channel */
88b40369 732 dev_dbg(&drv_data->pdev->dev, "doing dma transfer\n");
a5f6abd4
WB		 733 if (width == CFG_SPI_WORDSIZE16) {
734 set_dma_x_count(CH_SPI, drv_data->len);
735 set_dma_x_modify(CH_SPI, 2);
736 dma_width = WDSIZE_16;
737 } else {
738 set_dma_x_count(CH_SPI, drv_data->len);
739 set_dma_x_modify(CH_SPI, 1);
740 dma_width = WDSIZE_8;
741 }
742
743 /* set transfer width,direction. And enable spi */
744 cr = (read_CTRL() & (~BIT_CTL_TIMOD));
745
746 /* dirty hack for autobuffer DMA mode */
747 if (drv_data->tx_dma == 0xFFFF) {
88b40369
BW		 748 dev_dbg(&drv_data->pdev->dev,
749 "doing autobuffer DMA out.\n");
a5f6abd4
WB		 750
751 /* no irq in autobuffer mode */
752 dma_config =
753 (DMAFLOW_AUTO | RESTART | dma_width | DI_EN);
754 set_dma_config(CH_SPI, dma_config);
755 set_dma_start_addr(CH_SPI, (unsigned long)drv_data->tx);
756 enable_dma(CH_SPI);
757 write_CTRL(cr | CFG_SPI_DMAWRITE | (width << 8) |
758 (CFG_SPI_ENABLE << 14));
759
760 /* just return here, there can only be one transfer in this mode */
761 message->status = 0;
762 giveback(drv_data);
763 return;
764 }
765
766 /* In dma mode, rx or tx must be NULL in one transfer */
767 if (drv_data->rx != NULL) {
768 /* set transfer mode, and enable SPI */
88b40369 769 dev_dbg(&drv_data->pdev->dev, "doing DMA in.\n");
a5f6abd4
WB		 770
771 /* disable SPI before write to TDBR */
772 write_CTRL(cr & ~BIT_CTL_ENABLE);
773
774 /* clear tx reg soformer data is not shifted out */
775 write_TDBR(0xFF);
776
777 set_dma_x_count(CH_SPI, drv_data->len);
778
779 /* start dma */
780 dma_enable_irq(CH_SPI);
781 dma_config = (WNR | RESTART | dma_width | DI_EN);
782 set_dma_config(CH_SPI, dma_config);
783 set_dma_start_addr(CH_SPI, (unsigned long)drv_data->rx);
784 enable_dma(CH_SPI);
785
786 cr |=
787 CFG_SPI_DMAREAD | (width << 8) | (CFG_SPI_ENABLE <<
788 14);
789 /* set transfer mode, and enable SPI */
790 write_CTRL(cr);
791 } else if (drv_data->tx != NULL) {
88b40369 792 dev_dbg(&drv_data->pdev->dev, "doing DMA out.\n");
a5f6abd4
WB		 793
794 /* start dma */
795 dma_enable_irq(CH_SPI);
796 dma_config = (RESTART | dma_width | DI_EN);
797 set_dma_config(CH_SPI, dma_config);
798 set_dma_start_addr(CH_SPI, (unsigned long)drv_data->tx);
799 enable_dma(CH_SPI);
800
801 write_CTRL(cr | CFG_SPI_DMAWRITE | (width << 8) |
802 (CFG_SPI_ENABLE << 14));
803
804 }
805 } else {
806 /* IO mode write then read */
88b40369 807 dev_dbg(&drv_data->pdev->dev, "doing IO transfer\n");
a5f6abd4
WB		 808
809 write_STAT(BIT_STAT_CLR);
810
811 if (drv_data->tx != NULL && drv_data->rx != NULL) {
812 /* full duplex mode */
813 BUG_ON((drv_data->tx_end - drv_data->tx) !=
814 (drv_data->rx_end - drv_data->rx));
88b40369
BW		 815 cr = (read_CTRL() & (~BIT_CTL_TIMOD));
816 cr |= CFG_SPI_WRITE | (width << 8) |
817 (CFG_SPI_ENABLE << 14);
818 dev_dbg(&drv_data->pdev->dev,
819 "IO duplex: cr is 0x%x\n", cr);
a5f6abd4
WB		 820
821 write_CTRL(cr);
822 SSYNC();
823
824 drv_data->duplex(drv_data);
825
826 if (drv_data->tx != drv_data->tx_end)
827 tranf_success = 0;
828 } else if (drv_data->tx != NULL) {
829 /* write only half duplex */
88b40369
BW		 830 cr = (read_CTRL() & (~BIT_CTL_TIMOD));
831 cr |= CFG_SPI_WRITE | (width << 8) |
832 (CFG_SPI_ENABLE << 14);
833 dev_dbg(&drv_data->pdev->dev,
834 "IO write: cr is 0x%x\n", cr);
a5f6abd4
WB		 835
836 write_CTRL(cr);
837 SSYNC();
838
839 drv_data->write(drv_data);
840
841 if (drv_data->tx != drv_data->tx_end)
842 tranf_success = 0;
843 } else if (drv_data->rx != NULL) {
844 /* read only half duplex */
88b40369
BW		 845 cr = (read_CTRL() & (~BIT_CTL_TIMOD));
846 cr |= CFG_SPI_READ | (width << 8) |
847 (CFG_SPI_ENABLE << 14);
848 dev_dbg(&drv_data->pdev->dev,
849 "IO read: cr is 0x%x\n", cr);
a5f6abd4
WB		 850
851 write_CTRL(cr);
852 SSYNC();
853
854 drv_data->read(drv_data);
855 if (drv_data->rx != drv_data->rx_end)
856 tranf_success = 0;
857 }
858
859 if (!tranf_success) {
88b40369
BW		 860 dev_dbg(&drv_data->pdev->dev,
861 "IO write error!\n");
a5f6abd4
WB		 862 message->state = ERROR_STATE;
863 } else {
864 /* Update total byte transfered */
865 message->actual_length += drv_data->len;
866
867 /* Move to next transfer of this msg */
868 message->state = next_transfer(drv_data);
869 }
870
871 /* Schedule next transfer tasklet */
872 tasklet_schedule(&drv_data->pump_transfers);
873
874 }
875}
876
877/* pop a msg from queue and kick off real transfer */
878static void pump_messages(struct work_struct *work)
879{
880 struct driver_data *drv_data = container_of(work, struct driver_data, pump_messages);
881 unsigned long flags;
882
883 /* Lock queue and check for queue work */
884 spin_lock_irqsave(&drv_data->lock, flags);
885 if (list_empty(&drv_data->queue) || drv_data->run == QUEUE_STOPPED) {
886 /* pumper kicked off but no work to do */
887 drv_data->busy = 0;
888 spin_unlock_irqrestore(&drv_data->lock, flags);
889 return;
890 }
891
892 /* Make sure we are not already running a message */
893 if (drv_data->cur_msg) {
894 spin_unlock_irqrestore(&drv_data->lock, flags);
895 return;
896 }
897
898 /* Extract head of queue */
899 drv_data->cur_msg = list_entry(drv_data->queue.next,
900 struct spi_message, queue);
901 list_del_init(&drv_data->cur_msg->queue);
902
903 /* Initial message state */
904 drv_data->cur_msg->state = START_STATE;
905 drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next,
906 struct spi_transfer, transfer_list);
907
908 /* Setup the SSP using the per chip configuration */
909 drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi);
910 restore_state(drv_data);
88b40369
BW		 911 dev_dbg(&drv_data->pdev->dev,
912 "got a message to pump, state is set to: baud %d, flag 0x%x, ctl 0x%x\n",
913 drv_data->cur_chip->baud, drv_data->cur_chip->flag,
914 drv_data->cur_chip->ctl_reg);
915
916 dev_dbg(&drv_data->pdev->dev,
917 "the first transfer len is %d\n",
918 drv_data->cur_transfer->len);
a5f6abd4
WB		 919
920 /* Mark as busy and launch transfers */
921 tasklet_schedule(&drv_data->pump_transfers);
922
923 drv_data->busy = 1;
924 spin_unlock_irqrestore(&drv_data->lock, flags);
925}
926
927/*
928 * got a msg to transfer, queue it in drv_data->queue.
929 * And kick off message pumper
930 */
931static int transfer(struct spi_device *spi, struct spi_message *msg)
932{
933 struct driver_data *drv_data = spi_master_get_devdata(spi->master);
934 unsigned long flags;
935
936 spin_lock_irqsave(&drv_data->lock, flags);
937
938 if (drv_data->run == QUEUE_STOPPED) {
939 spin_unlock_irqrestore(&drv_data->lock, flags);
940 return -ESHUTDOWN;
941 }
942
943 msg->actual_length = 0;
944 msg->status = -EINPROGRESS;
945 msg->state = START_STATE;
946
88b40369 947 dev_dbg(&spi->dev, "adding an msg in transfer() \n");
a5f6abd4
WB		 948 list_add_tail(&msg->queue, &drv_data->queue);
949
950 if (drv_data->run == QUEUE_RUNNING && !drv_data->busy)
951 queue_work(drv_data->workqueue, &drv_data->pump_messages);
952
953 spin_unlock_irqrestore(&drv_data->lock, flags);
954
955 return 0;
956}
957
958/* first setup for new devices */
959static int setup(struct spi_device *spi)
960{
961 struct bfin5xx_spi_chip *chip_info = NULL;
962 struct chip_data *chip;
963 struct driver_data *drv_data = spi_master_get_devdata(spi->master);
964 u8 spi_flg;
965
966 /* Abort device setup if requested features are not supported */
967 if (spi->mode & ~(SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST)) {
968 dev_err(&spi->dev, "requested mode not fully supported\n");
969 return -EINVAL;
970 }
971
972 /* Zero (the default) here means 8 bits */
973 if (!spi->bits_per_word)
974 spi->bits_per_word = 8;
975
976 if (spi->bits_per_word != 8 && spi->bits_per_word != 16)
977 return -EINVAL;
978
979 /* Only alloc (or use chip_info) on first setup */
980 chip = spi_get_ctldata(spi);
981 if (chip == NULL) {
982 chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
983 if (!chip)
984 return -ENOMEM;
985
986 chip->enable_dma = 0;
987 chip_info = spi->controller_data;
988 }
989
990 /* chip_info isn't always needed */
991 if (chip_info) {
992 chip->enable_dma = chip_info->enable_dma != 0
993 && drv_data->master_info->enable_dma;
994 chip->ctl_reg = chip_info->ctl_reg;
995 chip->bits_per_word = chip_info->bits_per_word;
996 chip->cs_change_per_word = chip_info->cs_change_per_word;
997 chip->cs_chg_udelay = chip_info->cs_chg_udelay;
998 }
999
1000 /* translate common spi framework into our register */
1001 if (spi->mode & SPI_CPOL)
1002 chip->ctl_reg |= CPOL;
1003 if (spi->mode & SPI_CPHA)
1004 chip->ctl_reg |= CPHA;
1005 if (spi->mode & SPI_LSB_FIRST)
1006 chip->ctl_reg |= LSBF;
1007 /* we dont support running in slave mode (yet?) */
1008 chip->ctl_reg |= MSTR;
1009
1010 /*
1011 * if any one SPI chip is registered and wants DMA, request the
1012 * DMA channel for it
1013 */
1014 if (chip->enable_dma && !dma_requested) {
1015 /* register dma irq handler */
1016 if (request_dma(CH_SPI, "BF53x_SPI_DMA") < 0) {
88b40369
BW		 1017 dev_dbg(&spi->dev,
1018 "Unable to request BlackFin SPI DMA channel\n");
a5f6abd4
WB		 1019 return -ENODEV;
1020 }
1021 if (set_dma_callback(CH_SPI, (void *)dma_irq_handler, drv_data)
1022 < 0) {
88b40369 1023 dev_dbg(&spi->dev, "Unable to set dma callback\n");
a5f6abd4
WB		 1024 return -EPERM;
1025 }
1026 dma_disable_irq(CH_SPI);
1027 dma_requested = 1;
1028 }
1029
1030 /*
1031 * Notice: for blackfin, the speed_hz is the value of register
1032 * SPI_BAUD, not the real baudrate
1033 */
1034 chip->baud = hz_to_spi_baud(spi->max_speed_hz);
1035 spi_flg = ~(1 << (spi->chip_select));
1036 chip->flag = ((u16) spi_flg << 8) | (1 << (spi->chip_select));
1037 chip->chip_select_num = spi->chip_select;
1038
1039 switch (chip->bits_per_word) {
1040 case 8:
1041 chip->n_bytes = 1;
1042 chip->width = CFG_SPI_WORDSIZE8;
1043 chip->read = chip->cs_change_per_word ?
1044 u8_cs_chg_reader : u8_reader;
1045 chip->write = chip->cs_change_per_word ?
1046 u8_cs_chg_writer : u8_writer;
1047 chip->duplex = chip->cs_change_per_word ?
1048 u8_cs_chg_duplex : u8_duplex;
1049 break;
1050
1051 case 16:
1052 chip->n_bytes = 2;
1053 chip->width = CFG_SPI_WORDSIZE16;
1054 chip->read = chip->cs_change_per_word ?
1055 u16_cs_chg_reader : u16_reader;
1056 chip->write = chip->cs_change_per_word ?
1057 u16_cs_chg_writer : u16_writer;
1058 chip->duplex = chip->cs_change_per_word ?
1059 u16_cs_chg_duplex : u16_duplex;
1060 break;
1061
1062 default:
1063 dev_err(&spi->dev, "%d bits_per_word is not supported\n",
1064 chip->bits_per_word);
1065 kfree(chip);
1066 return -ENODEV;
1067 }
1068
88b40369 1069 dev_dbg(&spi->dev, "setup spi chip %s, width is %d, dma is %d,",
a5f6abd4 1070 spi->modalias, chip->width, chip->enable_dma);
88b40369 1071 dev_dbg(&spi->dev, "ctl_reg is 0x%x, flag_reg is 0x%x\n",
a5f6abd4
WB		 1072 chip->ctl_reg, chip->flag);
1073
1074 spi_set_ctldata(spi, chip);
1075
1076 return 0;
1077}
1078
1079/*
1080 * callback for spi framework.
1081 * clean driver specific data
1082 */
88b40369 1083static void cleanup(struct spi_device *spi)
a5f6abd4 1084{
27bb9e79 1085 struct chip_data *chip = spi_get_ctldata(spi);
a5f6abd4
WB		 1086
1087 kfree(chip);
1088}
1089
1090static inline int init_queue(struct driver_data *drv_data)
1091{
1092 INIT_LIST_HEAD(&drv_data->queue);
1093 spin_lock_init(&drv_data->lock);
1094
1095 drv_data->run = QUEUE_STOPPED;
1096 drv_data->busy = 0;
1097
1098 /* init transfer tasklet */
1099 tasklet_init(&drv_data->pump_transfers,
1100 pump_transfers, (unsigned long)drv_data);
1101
1102 /* init messages workqueue */
1103 INIT_WORK(&drv_data->pump_messages, pump_messages);
1104 drv_data->workqueue =
1105 create_singlethread_workqueue(drv_data->master->cdev.dev->bus_id);
1106 if (drv_data->workqueue == NULL)
1107 return -EBUSY;
1108
1109 return 0;
1110}
1111
1112static inline int start_queue(struct driver_data *drv_data)
1113{
1114 unsigned long flags;
1115
1116 spin_lock_irqsave(&drv_data->lock, flags);
1117
1118 if (drv_data->run == QUEUE_RUNNING || drv_data->busy) {
1119 spin_unlock_irqrestore(&drv_data->lock, flags);
1120 return -EBUSY;
1121 }
1122
1123 drv_data->run = QUEUE_RUNNING;
1124 drv_data->cur_msg = NULL;
1125 drv_data->cur_transfer = NULL;
1126 drv_data->cur_chip = NULL;
1127 spin_unlock_irqrestore(&drv_data->lock, flags);
1128
1129 queue_work(drv_data->workqueue, &drv_data->pump_messages);
1130
1131 return 0;
1132}
1133
1134static inline int stop_queue(struct driver_data *drv_data)
1135{
1136 unsigned long flags;
1137 unsigned limit = 500;
1138 int status = 0;
1139
1140 spin_lock_irqsave(&drv_data->lock, flags);
1141
1142 /*
1143 * This is a bit lame, but is optimized for the common execution path.
1144 * A wait_queue on the drv_data->busy could be used, but then the common
1145 * execution path (pump_messages) would be required to call wake_up or
1146 * friends on every SPI message. Do this instead
1147 */
1148 drv_data->run = QUEUE_STOPPED;
1149 while (!list_empty(&drv_data->queue) && drv_data->busy && limit--) {
1150 spin_unlock_irqrestore(&drv_data->lock, flags);
1151 msleep(10);
1152 spin_lock_irqsave(&drv_data->lock, flags);
1153 }
1154
1155 if (!list_empty(&drv_data->queue) || drv_data->busy)
1156 status = -EBUSY;
1157
1158 spin_unlock_irqrestore(&drv_data->lock, flags);
1159
1160 return status;
1161}
1162
1163static inline int destroy_queue(struct driver_data *drv_data)
1164{
1165 int status;
1166
1167 status = stop_queue(drv_data);
1168 if (status != 0)
1169 return status;
1170
1171 destroy_workqueue(drv_data->workqueue);
1172
1173 return 0;
1174}
1175
1176static int __init bfin5xx_spi_probe(struct platform_device *pdev)
1177{
1178 struct device *dev = &pdev->dev;
1179 struct bfin5xx_spi_master *platform_info;
1180 struct spi_master *master;
1181 struct driver_data *drv_data = 0;
1182 int status = 0;
1183
1184 platform_info = dev->platform_data;
1185
1186 /* Allocate master with space for drv_data */
1187 master = spi_alloc_master(dev, sizeof(struct driver_data) + 16);
1188 if (!master) {
1189 dev_err(&pdev->dev, "can not alloc spi_master\n");
1190 return -ENOMEM;
1191 }
1192 drv_data = spi_master_get_devdata(master);
1193 drv_data->master = master;
1194 drv_data->master_info = platform_info;
1195 drv_data->pdev = pdev;
1196
1197 master->bus_num = pdev->id;
1198 master->num_chipselect = platform_info->num_chipselect;
1199 master->cleanup = cleanup;
1200 master->setup = setup;
1201 master->transfer = transfer;
1202
1203 /* Initial and start queue */
1204 status = init_queue(drv_data);
1205 if (status != 0) {
1206 dev_err(&pdev->dev, "problem initializing queue\n");
1207 goto out_error_queue_alloc;
1208 }
1209 status = start_queue(drv_data);
1210 if (status != 0) {
1211 dev_err(&pdev->dev, "problem starting queue\n");
1212 goto out_error_queue_alloc;
1213 }
1214
1215 /* Register with the SPI framework */
1216 platform_set_drvdata(pdev, drv_data);
1217 status = spi_register_master(master);
1218 if (status != 0) {
1219 dev_err(&pdev->dev, "problem registering spi master\n");
1220 goto out_error_queue_alloc;
1221 }
88b40369 1222 dev_dbg(&pdev->dev, "controller probe successfully\n");
a5f6abd4
WB		 1223 return status;
1224
1225 out_error_queue_alloc:
1226 destroy_queue(drv_data);
1227 spi_master_put(master);
1228 return status;
1229}
1230
1231/* stop hardware and remove the driver */
1232static int __devexit bfin5xx_spi_remove(struct platform_device *pdev)
1233{
1234 struct driver_data *drv_data = platform_get_drvdata(pdev);
1235 int status = 0;
1236
1237 if (!drv_data)
1238 return 0;
1239
1240 /* Remove the queue */
1241 status = destroy_queue(drv_data);
1242 if (status != 0)
1243 return status;
1244
1245 /* Disable the SSP at the peripheral and SOC level */
1246 bfin_spi_disable(drv_data);
1247
1248 /* Release DMA */
1249 if (drv_data->master_info->enable_dma) {
1250 if (dma_channel_active(CH_SPI))
1251 free_dma(CH_SPI);
1252 }
1253
1254 /* Disconnect from the SPI framework */
1255 spi_unregister_master(drv_data->master);
1256
1257 /* Prevent double remove */
1258 platform_set_drvdata(pdev, NULL);
1259
1260 return 0;
1261}
1262
1263#ifdef CONFIG_PM
1264static int bfin5xx_spi_suspend(struct platform_device *pdev, pm_message_t state)
1265{
1266 struct driver_data *drv_data = platform_get_drvdata(pdev);
1267 int status = 0;
1268
1269 status = stop_queue(drv_data);
1270 if (status != 0)
1271 return status;
1272
1273 /* stop hardware */
1274 bfin_spi_disable(drv_data);
1275
1276 return 0;
1277}
1278
1279static int bfin5xx_spi_resume(struct platform_device *pdev)
1280{
1281 struct driver_data *drv_data = platform_get_drvdata(pdev);
1282 int status = 0;
1283
1284 /* Enable the SPI interface */
1285 bfin_spi_enable(drv_data);
1286
1287 /* Start the queue running */
1288 status = start_queue(drv_data);
1289 if (status != 0) {
1290 dev_err(&pdev->dev, "problem starting queue (%d)\n", status);
1291 return status;
1292 }
1293
1294 return 0;
1295}
1296#else
1297#define bfin5xx_spi_suspend NULL
1298#define bfin5xx_spi_resume NULL
1299#endif /* CONFIG_PM */
1300
1301static struct platform_driver bfin5xx_spi_driver = {
88b40369
BW		 1302 .driver = {
1303 .name = "bfin-spi-master",
1304 .owner = THIS_MODULE,
1305 },
1306 .suspend = bfin5xx_spi_suspend,
1307 .resume = bfin5xx_spi_resume,
1308 .remove = __devexit_p(bfin5xx_spi_remove),
a5f6abd4
WB		 1309};
1310
1311static int __init bfin5xx_spi_init(void)
1312{
88b40369 1313 return platform_driver_probe(&bfin5xx_spi_driver, bfin5xx_spi_probe);
a5f6abd4 1314}
a5f6abd4
WB		 1315module_init(bfin5xx_spi_init);
1316
1317static void __exit bfin5xx_spi_exit(void)
1318{
1319 platform_driver_unregister(&bfin5xx_spi_driver);
1320}
a5f6abd4 1321module_exit(bfin5xx_spi_exit);
Linux 6.x block layer and io_uring tree(s)