1 /****************************************************************************
3 * Driver for the IFX 6x60 spi modem.
5 * Copyright (C) 2008 Option International
6 * Copyright (C) 2008 Filip Aben <f.aben@option.com>
7 * Denis Joseph Barrow <d.barow@option.com>
8 * Jan Dumon <j.dumon@option.com>
10 * Copyright (C) 2009, 2010 Intel Corp
11 * Russ Gorby <russ.gorby@intel.com>
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License version 2 as
15 * published by the Free Software Foundation.
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
27 * Driver modified by Intel from Option gtm501l_spi.c
30 * o The driver currently assumes a single device only. If you need to
31 * change this then look for saved_ifx_dev and add a device lookup
32 * o The driver is intended to be big-endian safe but has never been
33 * tested that way (no suitable hardware). There are a couple of FIXME
34 * notes by areas that may need addressing
35 * o Some of the GPIO naming/setup assumptions may need revisiting if
36 * you need to use this driver for another platform.
38 *****************************************************************************/
39 #include <linux/module.h>
40 #include <linux/termios.h>
41 #include <linux/tty.h>
42 #include <linux/device.h>
43 #include <linux/spi/spi.h>
44 #include <linux/tty.h>
45 #include <linux/kfifo.h>
46 #include <linux/tty_flip.h>
47 #include <linux/timer.h>
48 #include <linux/serial.h>
49 #include <linux/interrupt.h>
50 #include <linux/irq.h>
51 #include <linux/rfkill.h>
54 #include <linux/dmapool.h>
55 #include <linux/gpio.h>
56 #include <linux/sched.h>
57 #include <linux/time.h>
58 #include <linux/wait.h>
59 #include <linux/tty.h>
61 #include <linux/pm_runtime.h>
62 #include <linux/spi/ifx_modem.h>
63 #include <linux/delay.h>
67 #define IFX_SPI_MORE_MASK 0x10
68 #define IFX_SPI_MORE_BIT 12 /* bit position in u16 */
69 #define IFX_SPI_CTS_BIT 13 /* bit position in u16 */
70 #define IFX_SPI_MODE SPI_MODE_1
71 #define IFX_SPI_TTY_ID 0
72 #define IFX_SPI_TIMEOUT_SEC 2
73 #define IFX_SPI_HEADER_0 (-1)
74 #define IFX_SPI_HEADER_F (-2)
76 /* forward reference */
77 static void ifx_spi_handle_srdy(struct ifx_spi_device *ifx_dev);
80 static int spi_bpw = 16; /* 8, 16 or 32 bit word length */
81 static struct tty_driver *tty_drv;
82 static struct ifx_spi_device *saved_ifx_dev;
83 static struct lock_class_key ifx_spi_key;
85 /* GPIO/GPE settings */
88 * mrdy_set_high - set MRDY GPIO
89 * @ifx: device we are controlling
92 static inline void mrdy_set_high(struct ifx_spi_device *ifx)
94 gpio_set_value(ifx->gpio.mrdy, 1);
98 * mrdy_set_low - clear MRDY GPIO
99 * @ifx: device we are controlling
102 static inline void mrdy_set_low(struct ifx_spi_device *ifx)
104 gpio_set_value(ifx->gpio.mrdy, 0);
108 * ifx_spi_power_state_set
109 * @ifx_dev: our SPI device
112 * Set bit in power status and signal power system if status becomes non-0
115 ifx_spi_power_state_set(struct ifx_spi_device *ifx_dev, unsigned char val)
119 spin_lock_irqsave(&ifx_dev->power_lock, flags);
122 * if power status is already non-0, just update, else
125 if (!ifx_dev->power_status)
126 pm_runtime_get(&ifx_dev->spi_dev->dev);
127 ifx_dev->power_status |= val;
129 spin_unlock_irqrestore(&ifx_dev->power_lock, flags);
133 * ifx_spi_power_state_clear - clear power bit
134 * @ifx_dev: our SPI device
135 * @val: bits to clear
137 * clear bit in power status and signal power system if status becomes 0
140 ifx_spi_power_state_clear(struct ifx_spi_device *ifx_dev, unsigned char val)
144 spin_lock_irqsave(&ifx_dev->power_lock, flags);
146 if (ifx_dev->power_status) {
147 ifx_dev->power_status &= ~val;
148 if (!ifx_dev->power_status)
149 pm_runtime_put(&ifx_dev->spi_dev->dev);
152 spin_unlock_irqrestore(&ifx_dev->power_lock, flags);
158 * @len : number of bytes (not words) in the buffer
159 * @end: end of buffer
161 * Swap the contents of a buffer into big endian format
163 static inline void swap_buf(u16 *buf, int len, void *end)
167 len = ((len + 1) >> 1);
168 if ((void *)&buf[len] > end) {
169 pr_err("swap_buf: swap exceeds boundary (%p > %p)!",
173 for (n = 0; n < len; n++) {
174 *buf = cpu_to_be16(*buf);
180 * mrdy_assert - assert MRDY line
181 * @ifx_dev: our SPI device
183 * Assert mrdy and set timer to wait for SRDY interrupt, if SRDY is low
186 * FIXME: Can SRDY even go high as we are running this code ?
188 static void mrdy_assert(struct ifx_spi_device *ifx_dev)
190 int val = gpio_get_value(ifx_dev->gpio.srdy);
192 if (!test_and_set_bit(IFX_SPI_STATE_TIMER_PENDING,
194 ifx_dev->spi_timer.expires =
195 jiffies + IFX_SPI_TIMEOUT_SEC*HZ;
196 add_timer(&ifx_dev->spi_timer);
200 ifx_spi_power_state_set(ifx_dev, IFX_SPI_POWER_DATA_PENDING);
201 mrdy_set_high(ifx_dev);
205 * ifx_spi_hangup - hang up an IFX device
206 * @ifx_dev: our SPI device
208 * Hang up the tty attached to the IFX device if one is currently
209 * open. If not take no action
211 static void ifx_spi_ttyhangup(struct ifx_spi_device *ifx_dev)
213 struct tty_port *pport = &ifx_dev->tty_port;
214 struct tty_struct *tty = tty_port_tty_get(pport);
222 * ifx_spi_timeout - SPI timeout
223 * @arg: our SPI device
225 * The SPI has timed out: hang up the tty. Users will then see a hangup
228 static void ifx_spi_timeout(unsigned long arg)
230 struct ifx_spi_device *ifx_dev = (struct ifx_spi_device *)arg;
232 dev_warn(&ifx_dev->spi_dev->dev, "*** SPI Timeout ***");
233 ifx_spi_ttyhangup(ifx_dev);
234 mrdy_set_low(ifx_dev);
235 clear_bit(IFX_SPI_STATE_TIMER_PENDING, &ifx_dev->flags);
238 /* char/tty operations */
241 * ifx_spi_tiocmget - get modem lines
242 * @tty: our tty device
243 * @filp: file handle issuing the request
245 * Map the signal state into Linux modem flags and report the value
248 static int ifx_spi_tiocmget(struct tty_struct *tty)
251 struct ifx_spi_device *ifx_dev = tty->driver_data;
254 (test_bit(IFX_SPI_RTS, &ifx_dev->signal_state) ? TIOCM_RTS : 0) |
255 (test_bit(IFX_SPI_DTR, &ifx_dev->signal_state) ? TIOCM_DTR : 0) |
256 (test_bit(IFX_SPI_CTS, &ifx_dev->signal_state) ? TIOCM_CTS : 0) |
257 (test_bit(IFX_SPI_DSR, &ifx_dev->signal_state) ? TIOCM_DSR : 0) |
258 (test_bit(IFX_SPI_DCD, &ifx_dev->signal_state) ? TIOCM_CAR : 0) |
259 (test_bit(IFX_SPI_RI, &ifx_dev->signal_state) ? TIOCM_RNG : 0);
264 * ifx_spi_tiocmset - set modem bits
265 * @tty: the tty structure
266 * @filp: file handle issuing the request
268 * @clear: bits to clear
270 * The IFX6x60 only supports DTR and RTS. Set them accordingly
271 * and flag that an update to the modem is needed.
273 * FIXME: do we need to kick the tranfers when we do this ?
275 static int ifx_spi_tiocmset(struct tty_struct *tty, struct file *filp,
276 unsigned int set, unsigned int clear)
278 struct ifx_spi_device *ifx_dev = tty->driver_data;
281 set_bit(IFX_SPI_RTS, &ifx_dev->signal_state);
283 set_bit(IFX_SPI_DTR, &ifx_dev->signal_state);
284 if (clear & TIOCM_RTS)
285 clear_bit(IFX_SPI_RTS, &ifx_dev->signal_state);
286 if (clear & TIOCM_DTR)
287 clear_bit(IFX_SPI_DTR, &ifx_dev->signal_state);
289 set_bit(IFX_SPI_UPDATE, &ifx_dev->signal_state);
294 * ifx_spi_open - called on tty open
295 * @tty: our tty device
296 * @filp: file handle being associated with the tty
298 * Open the tty interface. We let the tty_port layer do all the work
301 * FIXME: Remove single device assumption and saved_ifx_dev
303 static int ifx_spi_open(struct tty_struct *tty, struct file *filp)
305 return tty_port_open(&saved_ifx_dev->tty_port, tty, filp);
309 * ifx_spi_close - called when our tty closes
310 * @tty: the tty being closed
311 * @filp: the file handle being closed
313 * Perform the close of the tty. We use the tty_port layer to do all
316 static void ifx_spi_close(struct tty_struct *tty, struct file *filp)
318 struct ifx_spi_device *ifx_dev = tty->driver_data;
319 tty_port_close(&ifx_dev->tty_port, tty, filp);
320 /* FIXME: should we do an ifx_spi_reset here ? */
324 * ifx_decode_spi_header - decode received header
325 * @buffer: the received data
326 * @length: decoded length
327 * @more: decoded more flag
328 * @received_cts: status of cts we received
330 * Note how received_cts is handled -- if header is all F it is left
331 * the same as it was, if header is all 0 it is set to 0 otherwise it is
332 * taken from the incoming header.
336 static int ifx_spi_decode_spi_header(unsigned char *buffer, int *length,
337 unsigned char *more, unsigned char *received_cts)
341 u16 *in_buffer = (u16 *)buffer;
346 if (h1 == 0 && h2 == 0) {
348 return IFX_SPI_HEADER_0;
349 } else if (h1 == 0xffff && h2 == 0xffff) {
350 /* spi_slave_cts remains as it was */
351 return IFX_SPI_HEADER_F;
354 *length = h1 & 0xfff; /* upper bits of byte are flags */
355 *more = (buffer[1] >> IFX_SPI_MORE_BIT) & 1;
356 *received_cts = (buffer[3] >> IFX_SPI_CTS_BIT) & 1;
361 * ifx_setup_spi_header - set header fields
362 * @txbuffer: pointer to start of SPI buffer
364 * @more: indicate if more to follow
366 * Format up an SPI header for a transfer
370 static void ifx_spi_setup_spi_header(unsigned char *txbuffer, int tx_count,
373 *(u16 *)(txbuffer) = tx_count;
374 *(u16 *)(txbuffer+2) = IFX_SPI_PAYLOAD_SIZE;
375 txbuffer[1] |= (more << IFX_SPI_MORE_BIT) & IFX_SPI_MORE_MASK;
379 * ifx_spi_wakeup_serial - SPI space made
380 * @port_data: our SPI device
382 * We have emptied the FIFO enough that we want to get more data
383 * queued into it. Poke the line discipline via tty_wakeup so that
384 * it will feed us more bits
386 static void ifx_spi_wakeup_serial(struct ifx_spi_device *ifx_dev)
388 struct tty_struct *tty;
390 tty = tty_port_tty_get(&ifx_dev->tty_port);
398 * ifx_spi_prepare_tx_buffer - prepare transmit frame
399 * @ifx_dev: our SPI device
401 * The transmit buffr needs a header and various other bits of
402 * information followed by as much data as we can pull from the FIFO
403 * and transfer. This function formats up a suitable buffer in the
406 * FIXME: performance - should we wake the tty when the queue is half
409 static int ifx_spi_prepare_tx_buffer(struct ifx_spi_device *ifx_dev)
414 unsigned char *tx_buffer;
416 tx_buffer = ifx_dev->tx_buffer;
417 memset(tx_buffer, 0, IFX_SPI_TRANSFER_SIZE);
419 /* make room for required SPI header */
420 tx_buffer += IFX_SPI_HEADER_OVERHEAD;
421 tx_count = IFX_SPI_HEADER_OVERHEAD;
423 /* clear to signal no more data if this turns out to be the
424 * last buffer sent in a sequence */
425 ifx_dev->spi_more = 0;
427 /* if modem cts is set, just send empty buffer */
428 if (!ifx_dev->spi_slave_cts) {
429 /* see if there's tx data */
430 queue_length = kfifo_len(&ifx_dev->tx_fifo);
431 if (queue_length != 0) {
432 /* data to mux -- see if there's room for it */
433 temp_count = min(queue_length, IFX_SPI_PAYLOAD_SIZE);
434 temp_count = kfifo_out_locked(&ifx_dev->tx_fifo,
435 tx_buffer, temp_count,
436 &ifx_dev->fifo_lock);
438 /* update buffer pointer and data count in message */
439 tx_buffer += temp_count;
440 tx_count += temp_count;
441 if (temp_count == queue_length)
442 /* poke port to get more data */
443 ifx_spi_wakeup_serial(ifx_dev);
444 else /* more data in port, use next SPI message */
445 ifx_dev->spi_more = 1;
448 /* have data and info for header -- set up SPI header in buffer */
449 /* spi header needs payload size, not entire buffer size */
450 ifx_spi_setup_spi_header(ifx_dev->tx_buffer,
451 tx_count-IFX_SPI_HEADER_OVERHEAD,
453 /* swap actual data in the buffer */
454 swap_buf((u16 *)(ifx_dev->tx_buffer), tx_count,
455 &ifx_dev->tx_buffer[IFX_SPI_TRANSFER_SIZE]);
460 * ifx_spi_write - line discipline write
461 * @tty: our tty device
462 * @buf: pointer to buffer to write (kernel space)
463 * @count: size of buffer
465 * Write the characters we have been given into the FIFO. If the device
466 * is not active then activate it, when the SRDY line is asserted back
467 * this will commence I/O
469 static int ifx_spi_write(struct tty_struct *tty, const unsigned char *buf,
472 struct ifx_spi_device *ifx_dev = tty->driver_data;
473 unsigned char *tmp_buf = (unsigned char *)buf;
474 int tx_count = kfifo_in_locked(&ifx_dev->tx_fifo, tmp_buf, count,
475 &ifx_dev->fifo_lock);
476 mrdy_assert(ifx_dev);
481 * ifx_spi_chars_in_buffer - line discipline helper
482 * @tty: our tty device
484 * Report how much data we can accept before we drop bytes. As we use
485 * a simple FIFO this is nice and easy.
487 static int ifx_spi_write_room(struct tty_struct *tty)
489 struct ifx_spi_device *ifx_dev = tty->driver_data;
490 return IFX_SPI_FIFO_SIZE - kfifo_len(&ifx_dev->tx_fifo);
494 * ifx_spi_chars_in_buffer - line discipline helper
495 * @tty: our tty device
497 * Report how many characters we have buffered. In our case this is the
498 * number of bytes sitting in our transmit FIFO.
500 static int ifx_spi_chars_in_buffer(struct tty_struct *tty)
502 struct ifx_spi_device *ifx_dev = tty->driver_data;
503 return kfifo_len(&ifx_dev->tx_fifo);
508 * @port: our tty port
510 * tty port hang up. Called when tty_hangup processing is invoked either
511 * by loss of carrier, or by software (eg vhangup). Serialized against
512 * activate/shutdown by the tty layer.
514 static void ifx_spi_hangup(struct tty_struct *tty)
516 struct ifx_spi_device *ifx_dev = tty->driver_data;
517 tty_port_hangup(&ifx_dev->tty_port);
522 * @port: our tty port
524 * tty port activate method - called for first open. Serialized
525 * with hangup and shutdown by the tty layer.
527 static int ifx_port_activate(struct tty_port *port, struct tty_struct *tty)
529 struct ifx_spi_device *ifx_dev =
530 container_of(port, struct ifx_spi_device, tty_port);
532 /* clear any old data; can't do this in 'close' */
533 kfifo_reset(&ifx_dev->tx_fifo);
535 /* put port data into this tty */
536 tty->driver_data = ifx_dev;
538 /* allows flip string push from int context */
539 tty->low_latency = 1;
546 * @port: our tty port
548 * tty port shutdown method - called for last port close. Serialized
549 * with hangup and activate by the tty layer.
551 static void ifx_port_shutdown(struct tty_port *port)
553 struct ifx_spi_device *ifx_dev =
554 container_of(port, struct ifx_spi_device, tty_port);
556 mrdy_set_low(ifx_dev);
557 clear_bit(IFX_SPI_STATE_TIMER_PENDING, &ifx_dev->flags);
558 tasklet_kill(&ifx_dev->io_work_tasklet);
561 static const struct tty_port_operations ifx_tty_port_ops = {
562 .activate = ifx_port_activate,
563 .shutdown = ifx_port_shutdown,
566 static const struct tty_operations ifx_spi_serial_ops = {
567 .open = ifx_spi_open,
568 .close = ifx_spi_close,
569 .write = ifx_spi_write,
570 .hangup = ifx_spi_hangup,
571 .write_room = ifx_spi_write_room,
572 .chars_in_buffer = ifx_spi_chars_in_buffer,
573 .tiocmget = ifx_spi_tiocmget,
574 .tiocmset = ifx_spi_tiocmset,
578 * ifx_spi_insert_fip_string - queue received data
579 * @ifx_ser: our SPI device
580 * @chars: buffer we have received
581 * @size: number of chars reeived
583 * Queue bytes to the tty assuming the tty side is currently open. If
584 * not the discard the data.
586 static void ifx_spi_insert_flip_string(struct ifx_spi_device *ifx_dev,
587 unsigned char *chars, size_t size)
589 struct tty_struct *tty = tty_port_tty_get(&ifx_dev->tty_port);
592 tty_insert_flip_string(tty, chars, size);
593 tty_flip_buffer_push(tty);
598 * ifx_spi_complete - SPI transfer completed
599 * @ctx: our SPI device
601 * An SPI transfer has completed. Process any received data and kick off
602 * any further transmits we can commence.
604 static void ifx_spi_complete(void *ctx)
606 struct ifx_spi_device *ifx_dev = ctx;
607 struct tty_struct *tty;
608 struct tty_ldisc *ldisc = NULL;
613 int local_write_pending = 0;
618 mrdy_set_low(ifx_dev);
620 if (!ifx_dev->spi_msg.status) {
621 /* check header validity, get comm flags */
622 swap_buf((u16 *)ifx_dev->rx_buffer, IFX_SPI_HEADER_OVERHEAD,
623 &ifx_dev->rx_buffer[IFX_SPI_HEADER_OVERHEAD]);
624 decode_result = ifx_spi_decode_spi_header(ifx_dev->rx_buffer,
625 &length, &more, &cts);
626 if (decode_result == IFX_SPI_HEADER_0) {
627 dev_dbg(&ifx_dev->spi_dev->dev,
628 "ignore input: invalid header 0");
629 ifx_dev->spi_slave_cts = 0;
631 } else if (decode_result == IFX_SPI_HEADER_F) {
632 dev_dbg(&ifx_dev->spi_dev->dev,
633 "ignore input: invalid header F");
637 ifx_dev->spi_slave_cts = cts;
639 actual_length = min((unsigned int)length,
640 ifx_dev->spi_msg.actual_length);
641 swap_buf((u16 *)(ifx_dev->rx_buffer + IFX_SPI_HEADER_OVERHEAD),
643 &ifx_dev->rx_buffer[IFX_SPI_TRANSFER_SIZE]);
644 ifx_spi_insert_flip_string(
646 ifx_dev->rx_buffer + IFX_SPI_HEADER_OVERHEAD,
647 (size_t)actual_length);
649 dev_dbg(&ifx_dev->spi_dev->dev, "SPI transfer error %d",
650 ifx_dev->spi_msg.status);
654 if (ifx_dev->write_pending) {
655 ifx_dev->write_pending = 0;
656 local_write_pending = 1;
659 clear_bit(IFX_SPI_STATE_IO_IN_PROGRESS, &(ifx_dev->flags));
661 queue_length = kfifo_len(&ifx_dev->tx_fifo);
662 srdy = gpio_get_value(ifx_dev->gpio.srdy);
664 ifx_spi_power_state_clear(ifx_dev, IFX_SPI_POWER_SRDY);
666 /* schedule output if there is more to do */
667 if (test_and_clear_bit(IFX_SPI_STATE_IO_READY, &ifx_dev->flags))
668 tasklet_schedule(&ifx_dev->io_work_tasklet);
670 if (more || ifx_dev->spi_more || queue_length > 0 ||
671 local_write_pending) {
672 if (ifx_dev->spi_slave_cts) {
674 mrdy_assert(ifx_dev);
676 mrdy_assert(ifx_dev);
679 * poke line discipline driver if any for more data
680 * may or may not get more data to write
681 * for now, say not busy
683 ifx_spi_power_state_clear(ifx_dev,
684 IFX_SPI_POWER_DATA_PENDING);
685 tty = tty_port_tty_get(&ifx_dev->tty_port);
687 ldisc = tty_ldisc_ref(tty);
689 ldisc->ops->write_wakeup(tty);
690 tty_ldisc_deref(ldisc);
699 * ifx_spio_io - I/O tasklet
700 * @data: our SPI device
702 * Queue data for transmission if possible and then kick off the
705 static void ifx_spi_io(unsigned long data)
708 struct ifx_spi_device *ifx_dev = (struct ifx_spi_device *) data;
710 if (!test_and_set_bit(IFX_SPI_STATE_IO_IN_PROGRESS, &ifx_dev->flags)) {
711 if (ifx_dev->gpio.unack_srdy_int_nb > 0)
712 ifx_dev->gpio.unack_srdy_int_nb--;
714 ifx_spi_prepare_tx_buffer(ifx_dev);
716 spi_message_init(&ifx_dev->spi_msg);
717 INIT_LIST_HEAD(&ifx_dev->spi_msg.queue);
719 ifx_dev->spi_msg.context = ifx_dev;
720 ifx_dev->spi_msg.complete = ifx_spi_complete;
722 /* set up our spi transfer */
723 /* note len is BYTES, not transfers */
724 ifx_dev->spi_xfer.len = IFX_SPI_TRANSFER_SIZE;
725 ifx_dev->spi_xfer.cs_change = 0;
726 ifx_dev->spi_xfer.speed_hz = ifx_dev->spi_dev->max_speed_hz;
727 /* ifx_dev->spi_xfer.speed_hz = 390625; */
728 ifx_dev->spi_xfer.bits_per_word = spi_bpw;
730 ifx_dev->spi_xfer.tx_buf = ifx_dev->tx_buffer;
731 ifx_dev->spi_xfer.rx_buf = ifx_dev->rx_buffer;
736 if (ifx_dev->use_dma) {
737 ifx_dev->spi_msg.is_dma_mapped = 1;
738 ifx_dev->tx_dma = ifx_dev->tx_bus;
739 ifx_dev->rx_dma = ifx_dev->rx_bus;
740 ifx_dev->spi_xfer.tx_dma = ifx_dev->tx_dma;
741 ifx_dev->spi_xfer.rx_dma = ifx_dev->rx_dma;
743 ifx_dev->spi_msg.is_dma_mapped = 0;
744 ifx_dev->tx_dma = (dma_addr_t)0;
745 ifx_dev->rx_dma = (dma_addr_t)0;
746 ifx_dev->spi_xfer.tx_dma = (dma_addr_t)0;
747 ifx_dev->spi_xfer.rx_dma = (dma_addr_t)0;
750 spi_message_add_tail(&ifx_dev->spi_xfer, &ifx_dev->spi_msg);
752 /* Assert MRDY. This may have already been done by the write
755 mrdy_assert(ifx_dev);
757 retval = spi_async(ifx_dev->spi_dev, &ifx_dev->spi_msg);
759 clear_bit(IFX_SPI_STATE_IO_IN_PROGRESS,
761 tasklet_schedule(&ifx_dev->io_work_tasklet);
765 ifx_dev->write_pending = 1;
769 * ifx_spi_free_port - free up the tty side
770 * @ifx_dev: IFX device going away
772 * Unregister and free up a port when the device goes away
774 static void ifx_spi_free_port(struct ifx_spi_device *ifx_dev)
776 if (ifx_dev->tty_dev)
777 tty_unregister_device(tty_drv, ifx_dev->minor);
778 kfifo_free(&ifx_dev->tx_fifo);
782 * ifx_spi_create_port - create a new port
783 * @ifx_dev: our spi device
785 * Allocate and initialise the tty port that goes with this interface
786 * and add it to the tty layer so that it can be opened.
788 static int ifx_spi_create_port(struct ifx_spi_device *ifx_dev)
791 struct tty_port *pport = &ifx_dev->tty_port;
793 spin_lock_init(&ifx_dev->fifo_lock);
794 lockdep_set_class_and_subclass(&ifx_dev->fifo_lock,
797 if (kfifo_alloc(&ifx_dev->tx_fifo, IFX_SPI_FIFO_SIZE, GFP_KERNEL)) {
802 tty_port_init(pport);
803 pport->ops = &ifx_tty_port_ops;
804 ifx_dev->minor = IFX_SPI_TTY_ID;
805 ifx_dev->tty_dev = tty_register_device(tty_drv, ifx_dev->minor,
806 &ifx_dev->spi_dev->dev);
807 if (IS_ERR(ifx_dev->tty_dev)) {
808 dev_dbg(&ifx_dev->spi_dev->dev,
809 "%s: registering tty device failed", __func__);
810 ret = PTR_ERR(ifx_dev->tty_dev);
816 ifx_spi_free_port(ifx_dev);
821 * ifx_spi_handle_srdy - handle SRDY
822 * @ifx_dev: device asserting SRDY
824 * Check our device state and see what we need to kick off when SRDY
825 * is asserted. This usually means killing the timer and firing off the
828 static void ifx_spi_handle_srdy(struct ifx_spi_device *ifx_dev)
830 if (test_bit(IFX_SPI_STATE_TIMER_PENDING, &ifx_dev->flags)) {
831 del_timer_sync(&ifx_dev->spi_timer);
832 clear_bit(IFX_SPI_STATE_TIMER_PENDING, &ifx_dev->flags);
835 ifx_spi_power_state_set(ifx_dev, IFX_SPI_POWER_SRDY);
837 if (!test_bit(IFX_SPI_STATE_IO_IN_PROGRESS, &ifx_dev->flags))
838 tasklet_schedule(&ifx_dev->io_work_tasklet);
840 set_bit(IFX_SPI_STATE_IO_READY, &ifx_dev->flags);
844 * ifx_spi_srdy_interrupt - SRDY asserted
845 * @irq: our IRQ number
846 * @dev: our ifx device
848 * The modem asserted SRDY. Handle the srdy event
850 static irqreturn_t ifx_spi_srdy_interrupt(int irq, void *dev)
852 struct ifx_spi_device *ifx_dev = dev;
853 ifx_dev->gpio.unack_srdy_int_nb++;
854 ifx_spi_handle_srdy(ifx_dev);
859 * ifx_spi_reset_interrupt - Modem has changed reset state
860 * @irq: interrupt number
861 * @dev: our device pointer
863 * The modem has either entered or left reset state. Check the GPIO
866 * FIXME: review locking on MR_INPROGRESS versus
867 * parallel unsolicited reset/solicited reset
869 static irqreturn_t ifx_spi_reset_interrupt(int irq, void *dev)
871 struct ifx_spi_device *ifx_dev = dev;
872 int val = gpio_get_value(ifx_dev->gpio.reset_out);
873 int solreset = test_bit(MR_START, &ifx_dev->mdm_reset_state);
877 set_bit(MR_INPROGRESS, &ifx_dev->mdm_reset_state);
879 /* unsolicited reset */
880 ifx_spi_ttyhangup(ifx_dev);
884 clear_bit(MR_INPROGRESS, &ifx_dev->mdm_reset_state);
886 set_bit(MR_COMPLETE, &ifx_dev->mdm_reset_state);
887 wake_up(&ifx_dev->mdm_reset_wait);
894 * ifx_spi_free_device - free device
895 * @ifx_dev: device to free
897 * Free the IFX device
899 static void ifx_spi_free_device(struct ifx_spi_device *ifx_dev)
901 ifx_spi_free_port(ifx_dev);
902 dma_free_coherent(&ifx_dev->spi_dev->dev,
903 IFX_SPI_TRANSFER_SIZE,
906 dma_free_coherent(&ifx_dev->spi_dev->dev,
907 IFX_SPI_TRANSFER_SIZE,
913 * ifx_spi_reset - reset modem
914 * @ifx_dev: modem to reset
916 * Perform a reset on the modem
918 static int ifx_spi_reset(struct ifx_spi_device *ifx_dev)
922 * set up modem power, reset
924 * delays are required on some platforms for the modem
927 set_bit(MR_START, &ifx_dev->mdm_reset_state);
928 gpio_set_value(ifx_dev->gpio.po, 0);
929 gpio_set_value(ifx_dev->gpio.reset, 0);
931 gpio_set_value(ifx_dev->gpio.reset, 1);
933 gpio_set_value(ifx_dev->gpio.po, 1);
935 gpio_set_value(ifx_dev->gpio.po, 0);
936 ret = wait_event_timeout(ifx_dev->mdm_reset_wait,
937 test_bit(MR_COMPLETE,
938 &ifx_dev->mdm_reset_state),
941 dev_warn(&ifx_dev->spi_dev->dev, "Modem reset timeout: (state:%lx)",
942 ifx_dev->mdm_reset_state);
944 ifx_dev->mdm_reset_state = 0;
949 * ifx_spi_spi_probe - probe callback
950 * @spi: our possible matching SPI device
952 * Probe for a 6x60 modem on SPI bus. Perform any needed device and
956 * - Support for multiple devices
957 * - Split out MID specific GPIO handling eventually
960 static int ifx_spi_spi_probe(struct spi_device *spi)
964 struct ifx_modem_platform_data *pl_data;
965 struct ifx_spi_device *ifx_dev;
968 dev_dbg(&spi->dev, "ignoring subsequent detection");
972 pl_data = (struct ifx_modem_platform_data *)spi->dev.platform_data;
974 dev_err(&spi->dev, "missing platform data!");
978 /* initialize structure to hold our device variables */
979 ifx_dev = kzalloc(sizeof(struct ifx_spi_device), GFP_KERNEL);
981 dev_err(&spi->dev, "spi device allocation failed");
984 saved_ifx_dev = ifx_dev;
985 ifx_dev->spi_dev = spi;
986 clear_bit(IFX_SPI_STATE_IO_IN_PROGRESS, &ifx_dev->flags);
987 spin_lock_init(&ifx_dev->write_lock);
988 spin_lock_init(&ifx_dev->power_lock);
989 ifx_dev->power_status = 0;
990 init_timer(&ifx_dev->spi_timer);
991 ifx_dev->spi_timer.function = ifx_spi_timeout;
992 ifx_dev->spi_timer.data = (unsigned long)ifx_dev;
993 ifx_dev->modem = pl_data->modem_type;
994 ifx_dev->use_dma = pl_data->use_dma;
995 ifx_dev->max_hz = pl_data->max_hz;
996 /* initialize spi mode, etc */
997 spi->max_speed_hz = ifx_dev->max_hz;
998 spi->mode = IFX_SPI_MODE | (SPI_LOOP & spi->mode);
999 spi->bits_per_word = spi_bpw;
1000 ret = spi_setup(spi);
1002 dev_err(&spi->dev, "SPI setup wasn't successful %d", ret);
1006 /* ensure SPI protocol flags are initialized to enable transfer */
1007 ifx_dev->spi_more = 0;
1008 ifx_dev->spi_slave_cts = 0;
1010 /*initialize transfer and dma buffers */
1011 ifx_dev->tx_buffer = dma_alloc_coherent(ifx_dev->spi_dev->dev.parent,
1012 IFX_SPI_TRANSFER_SIZE,
1015 if (!ifx_dev->tx_buffer) {
1016 dev_err(&spi->dev, "DMA-TX buffer allocation failed");
1020 ifx_dev->rx_buffer = dma_alloc_coherent(ifx_dev->spi_dev->dev.parent,
1021 IFX_SPI_TRANSFER_SIZE,
1024 if (!ifx_dev->rx_buffer) {
1025 dev_err(&spi->dev, "DMA-RX buffer allocation failed");
1030 /* initialize waitq for modem reset */
1031 init_waitqueue_head(&ifx_dev->mdm_reset_wait);
1033 spi_set_drvdata(spi, ifx_dev);
1034 tasklet_init(&ifx_dev->io_work_tasklet, ifx_spi_io,
1035 (unsigned long)ifx_dev);
1037 set_bit(IFX_SPI_STATE_PRESENT, &ifx_dev->flags);
1039 /* create our tty port */
1040 ret = ifx_spi_create_port(ifx_dev);
1042 dev_err(&spi->dev, "create default tty port failed");
1046 ifx_dev->gpio.reset = pl_data->rst_pmu;
1047 ifx_dev->gpio.po = pl_data->pwr_on;
1048 ifx_dev->gpio.mrdy = pl_data->mrdy;
1049 ifx_dev->gpio.srdy = pl_data->srdy;
1050 ifx_dev->gpio.reset_out = pl_data->rst_out;
1052 dev_info(&spi->dev, "gpios %d, %d, %d, %d, %d",
1053 ifx_dev->gpio.reset, ifx_dev->gpio.po, ifx_dev->gpio.mrdy,
1054 ifx_dev->gpio.srdy, ifx_dev->gpio.reset_out);
1056 /* Configure gpios */
1057 ret = gpio_request(ifx_dev->gpio.reset, "ifxModem");
1059 dev_err(&spi->dev, "Unable to allocate GPIO%d (RESET)",
1060 ifx_dev->gpio.reset);
1063 ret += gpio_direction_output(ifx_dev->gpio.reset, 0);
1064 ret += gpio_export(ifx_dev->gpio.reset, 1);
1066 dev_err(&spi->dev, "Unable to configure GPIO%d (RESET)",
1067 ifx_dev->gpio.reset);
1072 ret = gpio_request(ifx_dev->gpio.po, "ifxModem");
1073 ret += gpio_direction_output(ifx_dev->gpio.po, 0);
1074 ret += gpio_export(ifx_dev->gpio.po, 1);
1076 dev_err(&spi->dev, "Unable to configure GPIO%d (ON)",
1082 ret = gpio_request(ifx_dev->gpio.mrdy, "ifxModem");
1084 dev_err(&spi->dev, "Unable to allocate GPIO%d (MRDY)",
1085 ifx_dev->gpio.mrdy);
1088 ret += gpio_export(ifx_dev->gpio.mrdy, 1);
1089 ret += gpio_direction_output(ifx_dev->gpio.mrdy, 0);
1091 dev_err(&spi->dev, "Unable to configure GPIO%d (MRDY)",
1092 ifx_dev->gpio.mrdy);
1097 ret = gpio_request(ifx_dev->gpio.srdy, "ifxModem");
1099 dev_err(&spi->dev, "Unable to allocate GPIO%d (SRDY)",
1100 ifx_dev->gpio.srdy);
1104 ret += gpio_export(ifx_dev->gpio.srdy, 1);
1105 ret += gpio_direction_input(ifx_dev->gpio.srdy);
1107 dev_err(&spi->dev, "Unable to configure GPIO%d (SRDY)",
1108 ifx_dev->gpio.srdy);
1113 ret = gpio_request(ifx_dev->gpio.reset_out, "ifxModem");
1115 dev_err(&spi->dev, "Unable to allocate GPIO%d (RESET_OUT)",
1116 ifx_dev->gpio.reset_out);
1119 ret += gpio_export(ifx_dev->gpio.reset_out, 1);
1120 ret += gpio_direction_input(ifx_dev->gpio.reset_out);
1122 dev_err(&spi->dev, "Unable to configure GPIO%d (RESET_OUT)",
1123 ifx_dev->gpio.reset_out);
1128 ret = request_irq(gpio_to_irq(ifx_dev->gpio.reset_out),
1129 ifx_spi_reset_interrupt,
1130 IRQF_TRIGGER_RISING|IRQF_TRIGGER_FALLING, DRVNAME,
1133 dev_err(&spi->dev, "Unable to get irq %x\n",
1134 gpio_to_irq(ifx_dev->gpio.reset_out));
1138 ret = ifx_spi_reset(ifx_dev);
1140 ret = request_irq(gpio_to_irq(ifx_dev->gpio.srdy),
1141 ifx_spi_srdy_interrupt,
1142 IRQF_TRIGGER_RISING, DRVNAME,
1145 dev_err(&spi->dev, "Unable to get irq %x",
1146 gpio_to_irq(ifx_dev->gpio.srdy));
1150 /* set pm runtime power state and register with power system */
1151 pm_runtime_set_active(&spi->dev);
1152 pm_runtime_enable(&spi->dev);
1154 /* handle case that modem is already signaling SRDY */
1155 /* no outgoing tty open at this point, this just satisfies the
1156 * modem's read and should reset communication properly
1158 srdy = gpio_get_value(ifx_dev->gpio.srdy);
1161 mrdy_assert(ifx_dev);
1162 ifx_spi_handle_srdy(ifx_dev);
1164 mrdy_set_low(ifx_dev);
1168 free_irq(gpio_to_irq(ifx_dev->gpio.reset_out), (void *)ifx_dev);
1170 gpio_free(ifx_dev->gpio.srdy);
1172 gpio_free(ifx_dev->gpio.mrdy);
1174 gpio_free(ifx_dev->gpio.reset);
1176 gpio_free(ifx_dev->gpio.po);
1178 gpio_free(ifx_dev->gpio.reset_out);
1180 ifx_spi_free_device(ifx_dev);
1181 saved_ifx_dev = NULL;
1186 * ifx_spi_spi_remove - SPI device was removed
1189 * FIXME: We should be shutting the device down here not in
1190 * the module unload path.
1193 static int ifx_spi_spi_remove(struct spi_device *spi)
1195 struct ifx_spi_device *ifx_dev = spi_get_drvdata(spi);
1197 tasklet_kill(&ifx_dev->io_work_tasklet);
1199 free_irq(gpio_to_irq(ifx_dev->gpio.reset_out), (void *)ifx_dev);
1200 free_irq(gpio_to_irq(ifx_dev->gpio.srdy), (void *)ifx_dev);
1202 gpio_free(ifx_dev->gpio.srdy);
1203 gpio_free(ifx_dev->gpio.mrdy);
1204 gpio_free(ifx_dev->gpio.reset);
1205 gpio_free(ifx_dev->gpio.po);
1206 gpio_free(ifx_dev->gpio.reset_out);
1208 /* free allocations */
1209 ifx_spi_free_device(ifx_dev);
1211 saved_ifx_dev = NULL;
1216 * ifx_spi_spi_shutdown - called on SPI shutdown
1219 * No action needs to be taken here
1222 static void ifx_spi_spi_shutdown(struct spi_device *spi)
1227 * various suspends and resumes have nothing to do
1228 * no hardware to save state for
1232 * ifx_spi_spi_suspend - suspend SPI on system suspend
1233 * @dev: device being suspended
1235 * Suspend the SPI side. No action needed on Intel MID platforms, may
1236 * need extending for other systems.
1238 static int ifx_spi_spi_suspend(struct spi_device *spi, pm_message_t msg)
1244 * ifx_spi_spi_resume - resume SPI side on system resume
1245 * @dev: device being suspended
1247 * Suspend the SPI side. No action needed on Intel MID platforms, may
1248 * need extending for other systems.
1250 static int ifx_spi_spi_resume(struct spi_device *spi)
1256 * ifx_spi_pm_suspend - suspend modem on system suspend
1257 * @dev: device being suspended
1259 * Suspend the modem. No action needed on Intel MID platforms, may
1260 * need extending for other systems.
1262 static int ifx_spi_pm_suspend(struct device *dev)
1268 * ifx_spi_pm_resume - resume modem on system resume
1269 * @dev: device being suspended
1271 * Allow the modem to resume. No action needed.
1273 * FIXME: do we need to reset anything here ?
1275 static int ifx_spi_pm_resume(struct device *dev)
1281 * ifx_spi_pm_runtime_resume - suspend modem
1282 * @dev: device being suspended
1284 * Allow the modem to resume. No action needed.
1286 static int ifx_spi_pm_runtime_resume(struct device *dev)
1292 * ifx_spi_pm_runtime_suspend - suspend modem
1293 * @dev: device being suspended
1295 * Allow the modem to suspend and thus suspend to continue up the
1298 static int ifx_spi_pm_runtime_suspend(struct device *dev)
1304 * ifx_spi_pm_runtime_idle - check if modem idle
1307 * Check conditions and queue runtime suspend if idle.
1309 static int ifx_spi_pm_runtime_idle(struct device *dev)
1311 struct spi_device *spi = to_spi_device(dev);
1312 struct ifx_spi_device *ifx_dev = spi_get_drvdata(spi);
1314 if (!ifx_dev->power_status)
1315 pm_runtime_suspend(dev);
1320 static const struct dev_pm_ops ifx_spi_pm = {
1321 .resume = ifx_spi_pm_resume,
1322 .suspend = ifx_spi_pm_suspend,
1323 .runtime_resume = ifx_spi_pm_runtime_resume,
1324 .runtime_suspend = ifx_spi_pm_runtime_suspend,
1325 .runtime_idle = ifx_spi_pm_runtime_idle
1328 static const struct spi_device_id ifx_id_table[] = {
1333 MODULE_DEVICE_TABLE(spi, ifx_id_table);
1335 /* spi operations */
1336 static const struct spi_driver ifx_spi_driver = {
1339 .bus = &spi_bus_type,
1341 .owner = THIS_MODULE},
1342 .probe = ifx_spi_spi_probe,
1343 .shutdown = ifx_spi_spi_shutdown,
1344 .remove = __devexit_p(ifx_spi_spi_remove),
1345 .suspend = ifx_spi_spi_suspend,
1346 .resume = ifx_spi_spi_resume,
1347 .id_table = ifx_id_table
1351 * ifx_spi_exit - module exit
1353 * Unload the module.
1356 static void __exit ifx_spi_exit(void)
1359 tty_unregister_driver(tty_drv);
1360 spi_unregister_driver((void *)&ifx_spi_driver);
1364 * ifx_spi_init - module entry point
1366 * Initialise the SPI and tty interfaces for the IFX SPI driver
1367 * We need to initialize upper-edge spi driver after the tty
1368 * driver because otherwise the spi probe will race
1371 static int __init ifx_spi_init(void)
1375 tty_drv = alloc_tty_driver(1);
1377 pr_err("%s: alloc_tty_driver failed", DRVNAME);
1381 tty_drv->magic = TTY_DRIVER_MAGIC;
1382 tty_drv->owner = THIS_MODULE;
1383 tty_drv->driver_name = DRVNAME;
1384 tty_drv->name = TTYNAME;
1385 tty_drv->minor_start = IFX_SPI_TTY_ID;
1387 tty_drv->type = TTY_DRIVER_TYPE_SERIAL;
1388 tty_drv->subtype = SERIAL_TYPE_NORMAL;
1389 tty_drv->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
1390 tty_drv->init_termios = tty_std_termios;
1392 tty_set_operations(tty_drv, &ifx_spi_serial_ops);
1394 result = tty_register_driver(tty_drv);
1396 pr_err("%s: tty_register_driver failed(%d)",
1398 put_tty_driver(tty_drv);
1402 result = spi_register_driver((void *)&ifx_spi_driver);
1404 pr_err("%s: spi_register_driver failed(%d)",
1406 tty_unregister_driver(tty_drv);
1411 module_init(ifx_spi_init);
1412 module_exit(ifx_spi_exit);
1414 MODULE_AUTHOR("Intel");
1415 MODULE_DESCRIPTION("IFX6x60 spi driver");
1416 MODULE_LICENSE("GPL");
1417 MODULE_INFO(Version, "0.1-IFX6x60");