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/dma-mapping.h>
40 #include <linux/module.h>
41 #include <linux/termios.h>
42 #include <linux/tty.h>
43 #include <linux/device.h>
44 #include <linux/spi/spi.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>
60 #include <linux/pm_runtime.h>
61 #include <linux/spi/ifx_modem.h>
62 #include <linux/delay.h>
63 #include <linux/reboot.h>
67 #define IFX_SPI_MORE_MASK 0x10
68 #define IFX_SPI_MORE_BIT 4 /* bit position in u8 */
69 #define IFX_SPI_CTS_BIT 6 /* bit position in u8 */
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 #define PO_POST_DELAY 200
77 #define IFX_MDM_RST_PMU 4
79 /* forward reference */
80 static void ifx_spi_handle_srdy(struct ifx_spi_device *ifx_dev);
81 static int ifx_modem_reboot_callback(struct notifier_block *nfb,
82 unsigned long event, void *data);
83 static int ifx_modem_power_off(struct ifx_spi_device *ifx_dev);
86 static int spi_bpw = 16; /* 8, 16 or 32 bit word length */
87 static struct tty_driver *tty_drv;
88 static struct ifx_spi_device *saved_ifx_dev;
89 static struct lock_class_key ifx_spi_key;
91 static struct notifier_block ifx_modem_reboot_notifier_block = {
92 .notifier_call = ifx_modem_reboot_callback,
95 static int ifx_modem_power_off(struct ifx_spi_device *ifx_dev)
97 gpio_set_value(IFX_MDM_RST_PMU, 1);
98 msleep(PO_POST_DELAY);
103 static int ifx_modem_reboot_callback(struct notifier_block *nfb,
104 unsigned long event, void *data)
107 ifx_modem_power_off(saved_ifx_dev);
109 pr_warn("no ifx modem active;\n");
114 /* GPIO/GPE settings */
117 * mrdy_set_high - set MRDY GPIO
118 * @ifx: device we are controlling
121 static inline void mrdy_set_high(struct ifx_spi_device *ifx)
123 gpio_set_value(ifx->gpio.mrdy, 1);
127 * mrdy_set_low - clear MRDY GPIO
128 * @ifx: device we are controlling
131 static inline void mrdy_set_low(struct ifx_spi_device *ifx)
133 gpio_set_value(ifx->gpio.mrdy, 0);
137 * ifx_spi_power_state_set
138 * @ifx_dev: our SPI device
141 * Set bit in power status and signal power system if status becomes non-0
144 ifx_spi_power_state_set(struct ifx_spi_device *ifx_dev, unsigned char val)
148 spin_lock_irqsave(&ifx_dev->power_lock, flags);
151 * if power status is already non-0, just update, else
154 if (!ifx_dev->power_status)
155 pm_runtime_get(&ifx_dev->spi_dev->dev);
156 ifx_dev->power_status |= val;
158 spin_unlock_irqrestore(&ifx_dev->power_lock, flags);
162 * ifx_spi_power_state_clear - clear power bit
163 * @ifx_dev: our SPI device
164 * @val: bits to clear
166 * clear bit in power status and signal power system if status becomes 0
169 ifx_spi_power_state_clear(struct ifx_spi_device *ifx_dev, unsigned char val)
173 spin_lock_irqsave(&ifx_dev->power_lock, flags);
175 if (ifx_dev->power_status) {
176 ifx_dev->power_status &= ~val;
177 if (!ifx_dev->power_status)
178 pm_runtime_put(&ifx_dev->spi_dev->dev);
181 spin_unlock_irqrestore(&ifx_dev->power_lock, flags);
187 * @len : number of bytes (not words) in the buffer
188 * @end: end of buffer
190 * Swap the contents of a buffer into big endian format
192 static inline void swap_buf_8(unsigned char *buf, int len, void *end)
194 /* don't swap buffer if SPI word width is 8 bits */
201 * @len : number of bytes (not words) in the buffer
202 * @end: end of buffer
204 * Swap the contents of a buffer into big endian format
206 static inline void swap_buf_16(unsigned char *buf, int len, void *end)
210 u16 *buf_16 = (u16 *)buf;
211 len = ((len + 1) >> 1);
212 if ((void *)&buf_16[len] > end) {
213 pr_err("swap_buf_16: swap exceeds boundary (%p > %p)!",
217 for (n = 0; n < len; n++) {
218 *buf_16 = cpu_to_be16(*buf_16);
226 * @len : number of bytes (not words) in the buffer
227 * @end: end of buffer
229 * Swap the contents of a buffer into big endian format
231 static inline void swap_buf_32(unsigned char *buf, int len, void *end)
235 u32 *buf_32 = (u32 *)buf;
236 len = (len + 3) >> 2;
238 if ((void *)&buf_32[len] > end) {
239 pr_err("swap_buf_32: swap exceeds boundary (%p > %p)!\n",
243 for (n = 0; n < len; n++) {
244 *buf_32 = cpu_to_be32(*buf_32);
250 * mrdy_assert - assert MRDY line
251 * @ifx_dev: our SPI device
253 * Assert mrdy and set timer to wait for SRDY interrupt, if SRDY is low
256 * FIXME: Can SRDY even go high as we are running this code ?
258 static void mrdy_assert(struct ifx_spi_device *ifx_dev)
260 int val = gpio_get_value(ifx_dev->gpio.srdy);
262 if (!test_and_set_bit(IFX_SPI_STATE_TIMER_PENDING,
264 mod_timer(&ifx_dev->spi_timer,jiffies + IFX_SPI_TIMEOUT_SEC*HZ);
268 ifx_spi_power_state_set(ifx_dev, IFX_SPI_POWER_DATA_PENDING);
269 mrdy_set_high(ifx_dev);
273 * ifx_spi_timeout - SPI timeout
274 * @arg: our SPI device
276 * The SPI has timed out: hang up the tty. Users will then see a hangup
279 static void ifx_spi_timeout(unsigned long arg)
281 struct ifx_spi_device *ifx_dev = (struct ifx_spi_device *)arg;
283 dev_warn(&ifx_dev->spi_dev->dev, "*** SPI Timeout ***");
284 tty_port_tty_hangup(&ifx_dev->tty_port, false);
285 mrdy_set_low(ifx_dev);
286 clear_bit(IFX_SPI_STATE_TIMER_PENDING, &ifx_dev->flags);
289 /* char/tty operations */
292 * ifx_spi_tiocmget - get modem lines
293 * @tty: our tty device
294 * @filp: file handle issuing the request
296 * Map the signal state into Linux modem flags and report the value
299 static int ifx_spi_tiocmget(struct tty_struct *tty)
302 struct ifx_spi_device *ifx_dev = tty->driver_data;
305 (test_bit(IFX_SPI_RTS, &ifx_dev->signal_state) ? TIOCM_RTS : 0) |
306 (test_bit(IFX_SPI_DTR, &ifx_dev->signal_state) ? TIOCM_DTR : 0) |
307 (test_bit(IFX_SPI_CTS, &ifx_dev->signal_state) ? TIOCM_CTS : 0) |
308 (test_bit(IFX_SPI_DSR, &ifx_dev->signal_state) ? TIOCM_DSR : 0) |
309 (test_bit(IFX_SPI_DCD, &ifx_dev->signal_state) ? TIOCM_CAR : 0) |
310 (test_bit(IFX_SPI_RI, &ifx_dev->signal_state) ? TIOCM_RNG : 0);
315 * ifx_spi_tiocmset - set modem bits
316 * @tty: the tty structure
318 * @clear: bits to clear
320 * The IFX6x60 only supports DTR and RTS. Set them accordingly
321 * and flag that an update to the modem is needed.
323 * FIXME: do we need to kick the tranfers when we do this ?
325 static int ifx_spi_tiocmset(struct tty_struct *tty,
326 unsigned int set, unsigned int clear)
328 struct ifx_spi_device *ifx_dev = tty->driver_data;
331 set_bit(IFX_SPI_RTS, &ifx_dev->signal_state);
333 set_bit(IFX_SPI_DTR, &ifx_dev->signal_state);
334 if (clear & TIOCM_RTS)
335 clear_bit(IFX_SPI_RTS, &ifx_dev->signal_state);
336 if (clear & TIOCM_DTR)
337 clear_bit(IFX_SPI_DTR, &ifx_dev->signal_state);
339 set_bit(IFX_SPI_UPDATE, &ifx_dev->signal_state);
344 * ifx_spi_open - called on tty open
345 * @tty: our tty device
346 * @filp: file handle being associated with the tty
348 * Open the tty interface. We let the tty_port layer do all the work
351 * FIXME: Remove single device assumption and saved_ifx_dev
353 static int ifx_spi_open(struct tty_struct *tty, struct file *filp)
355 return tty_port_open(&saved_ifx_dev->tty_port, tty, filp);
359 * ifx_spi_close - called when our tty closes
360 * @tty: the tty being closed
361 * @filp: the file handle being closed
363 * Perform the close of the tty. We use the tty_port layer to do all
366 static void ifx_spi_close(struct tty_struct *tty, struct file *filp)
368 struct ifx_spi_device *ifx_dev = tty->driver_data;
369 tty_port_close(&ifx_dev->tty_port, tty, filp);
370 /* FIXME: should we do an ifx_spi_reset here ? */
374 * ifx_decode_spi_header - decode received header
375 * @buffer: the received data
376 * @length: decoded length
377 * @more: decoded more flag
378 * @received_cts: status of cts we received
380 * Note how received_cts is handled -- if header is all F it is left
381 * the same as it was, if header is all 0 it is set to 0 otherwise it is
382 * taken from the incoming header.
386 static int ifx_spi_decode_spi_header(unsigned char *buffer, int *length,
387 unsigned char *more, unsigned char *received_cts)
391 u16 *in_buffer = (u16 *)buffer;
396 if (h1 == 0 && h2 == 0) {
399 return IFX_SPI_HEADER_0;
400 } else if (h1 == 0xffff && h2 == 0xffff) {
402 /* spi_slave_cts remains as it was */
403 return IFX_SPI_HEADER_F;
406 *length = h1 & 0xfff; /* upper bits of byte are flags */
407 *more = (buffer[1] >> IFX_SPI_MORE_BIT) & 1;
408 *received_cts = (buffer[3] >> IFX_SPI_CTS_BIT) & 1;
413 * ifx_setup_spi_header - set header fields
414 * @txbuffer: pointer to start of SPI buffer
416 * @more: indicate if more to follow
418 * Format up an SPI header for a transfer
422 static void ifx_spi_setup_spi_header(unsigned char *txbuffer, int tx_count,
425 *(u16 *)(txbuffer) = tx_count;
426 *(u16 *)(txbuffer+2) = IFX_SPI_PAYLOAD_SIZE;
427 txbuffer[1] |= (more << IFX_SPI_MORE_BIT) & IFX_SPI_MORE_MASK;
431 * ifx_spi_prepare_tx_buffer - prepare transmit frame
432 * @ifx_dev: our SPI device
434 * The transmit buffr needs a header and various other bits of
435 * information followed by as much data as we can pull from the FIFO
436 * and transfer. This function formats up a suitable buffer in the
439 * FIXME: performance - should we wake the tty when the queue is half
442 static int ifx_spi_prepare_tx_buffer(struct ifx_spi_device *ifx_dev)
447 unsigned char *tx_buffer;
449 tx_buffer = ifx_dev->tx_buffer;
451 /* make room for required SPI header */
452 tx_buffer += IFX_SPI_HEADER_OVERHEAD;
453 tx_count = IFX_SPI_HEADER_OVERHEAD;
455 /* clear to signal no more data if this turns out to be the
456 * last buffer sent in a sequence */
457 ifx_dev->spi_more = 0;
459 /* if modem cts is set, just send empty buffer */
460 if (!ifx_dev->spi_slave_cts) {
461 /* see if there's tx data */
462 queue_length = kfifo_len(&ifx_dev->tx_fifo);
463 if (queue_length != 0) {
464 /* data to mux -- see if there's room for it */
465 temp_count = min(queue_length, IFX_SPI_PAYLOAD_SIZE);
466 temp_count = kfifo_out_locked(&ifx_dev->tx_fifo,
467 tx_buffer, temp_count,
468 &ifx_dev->fifo_lock);
470 /* update buffer pointer and data count in message */
471 tx_buffer += temp_count;
472 tx_count += temp_count;
473 if (temp_count == queue_length)
474 /* poke port to get more data */
475 tty_port_tty_wakeup(&ifx_dev->tty_port);
476 else /* more data in port, use next SPI message */
477 ifx_dev->spi_more = 1;
480 /* have data and info for header -- set up SPI header in buffer */
481 /* spi header needs payload size, not entire buffer size */
482 ifx_spi_setup_spi_header(ifx_dev->tx_buffer,
483 tx_count-IFX_SPI_HEADER_OVERHEAD,
485 /* swap actual data in the buffer */
486 ifx_dev->swap_buf((ifx_dev->tx_buffer), tx_count,
487 &ifx_dev->tx_buffer[IFX_SPI_TRANSFER_SIZE]);
492 * ifx_spi_write - line discipline write
493 * @tty: our tty device
494 * @buf: pointer to buffer to write (kernel space)
495 * @count: size of buffer
497 * Write the characters we have been given into the FIFO. If the device
498 * is not active then activate it, when the SRDY line is asserted back
499 * this will commence I/O
501 static int ifx_spi_write(struct tty_struct *tty, const unsigned char *buf,
504 struct ifx_spi_device *ifx_dev = tty->driver_data;
505 unsigned char *tmp_buf = (unsigned char *)buf;
510 spin_lock_irqsave(&ifx_dev->fifo_lock, flags);
511 is_fifo_empty = kfifo_is_empty(&ifx_dev->tx_fifo);
512 tx_count = kfifo_in(&ifx_dev->tx_fifo, tmp_buf, count);
513 spin_unlock_irqrestore(&ifx_dev->fifo_lock, flags);
515 mrdy_assert(ifx_dev);
521 * ifx_spi_chars_in_buffer - line discipline helper
522 * @tty: our tty device
524 * Report how much data we can accept before we drop bytes. As we use
525 * a simple FIFO this is nice and easy.
527 static int ifx_spi_write_room(struct tty_struct *tty)
529 struct ifx_spi_device *ifx_dev = tty->driver_data;
530 return IFX_SPI_FIFO_SIZE - kfifo_len(&ifx_dev->tx_fifo);
534 * ifx_spi_chars_in_buffer - line discipline helper
535 * @tty: our tty device
537 * Report how many characters we have buffered. In our case this is the
538 * number of bytes sitting in our transmit FIFO.
540 static int ifx_spi_chars_in_buffer(struct tty_struct *tty)
542 struct ifx_spi_device *ifx_dev = tty->driver_data;
543 return kfifo_len(&ifx_dev->tx_fifo);
548 * @port: our tty port
550 * tty port hang up. Called when tty_hangup processing is invoked either
551 * by loss of carrier, or by software (eg vhangup). Serialized against
552 * activate/shutdown by the tty layer.
554 static void ifx_spi_hangup(struct tty_struct *tty)
556 struct ifx_spi_device *ifx_dev = tty->driver_data;
557 tty_port_hangup(&ifx_dev->tty_port);
562 * @port: our tty port
564 * tty port activate method - called for first open. Serialized
565 * with hangup and shutdown by the tty layer.
567 static int ifx_port_activate(struct tty_port *port, struct tty_struct *tty)
569 struct ifx_spi_device *ifx_dev =
570 container_of(port, struct ifx_spi_device, tty_port);
572 /* clear any old data; can't do this in 'close' */
573 kfifo_reset(&ifx_dev->tx_fifo);
575 /* clear any flag which may be set in port shutdown procedure */
576 clear_bit(IFX_SPI_STATE_IO_IN_PROGRESS, &ifx_dev->flags);
577 clear_bit(IFX_SPI_STATE_IO_READY, &ifx_dev->flags);
579 /* put port data into this tty */
580 tty->driver_data = ifx_dev;
582 /* allows flip string push from int context */
583 port->low_latency = 1;
585 /* set flag to allows data transfer */
586 set_bit(IFX_SPI_STATE_IO_AVAILABLE, &ifx_dev->flags);
593 * @port: our tty port
595 * tty port shutdown method - called for last port close. Serialized
596 * with hangup and activate by the tty layer.
598 static void ifx_port_shutdown(struct tty_port *port)
600 struct ifx_spi_device *ifx_dev =
601 container_of(port, struct ifx_spi_device, tty_port);
603 clear_bit(IFX_SPI_STATE_IO_AVAILABLE, &ifx_dev->flags);
604 mrdy_set_low(ifx_dev);
605 del_timer(&ifx_dev->spi_timer);
606 clear_bit(IFX_SPI_STATE_TIMER_PENDING, &ifx_dev->flags);
607 tasklet_kill(&ifx_dev->io_work_tasklet);
610 static const struct tty_port_operations ifx_tty_port_ops = {
611 .activate = ifx_port_activate,
612 .shutdown = ifx_port_shutdown,
615 static const struct tty_operations ifx_spi_serial_ops = {
616 .open = ifx_spi_open,
617 .close = ifx_spi_close,
618 .write = ifx_spi_write,
619 .hangup = ifx_spi_hangup,
620 .write_room = ifx_spi_write_room,
621 .chars_in_buffer = ifx_spi_chars_in_buffer,
622 .tiocmget = ifx_spi_tiocmget,
623 .tiocmset = ifx_spi_tiocmset,
627 * ifx_spi_insert_fip_string - queue received data
628 * @ifx_ser: our SPI device
629 * @chars: buffer we have received
630 * @size: number of chars reeived
632 * Queue bytes to the tty assuming the tty side is currently open. If
633 * not the discard the data.
635 static void ifx_spi_insert_flip_string(struct ifx_spi_device *ifx_dev,
636 unsigned char *chars, size_t size)
638 tty_insert_flip_string(&ifx_dev->tty_port, chars, size);
639 tty_flip_buffer_push(&ifx_dev->tty_port);
643 * ifx_spi_complete - SPI transfer completed
644 * @ctx: our SPI device
646 * An SPI transfer has completed. Process any received data and kick off
647 * any further transmits we can commence.
649 static void ifx_spi_complete(void *ctx)
651 struct ifx_spi_device *ifx_dev = ctx;
654 unsigned char more = 0;
656 int local_write_pending = 0;
661 mrdy_set_low(ifx_dev);
663 if (!ifx_dev->spi_msg.status) {
664 /* check header validity, get comm flags */
665 ifx_dev->swap_buf(ifx_dev->rx_buffer, IFX_SPI_HEADER_OVERHEAD,
666 &ifx_dev->rx_buffer[IFX_SPI_HEADER_OVERHEAD]);
667 decode_result = ifx_spi_decode_spi_header(ifx_dev->rx_buffer,
668 &length, &more, &cts);
669 if (decode_result == IFX_SPI_HEADER_0) {
670 dev_dbg(&ifx_dev->spi_dev->dev,
671 "ignore input: invalid header 0");
672 ifx_dev->spi_slave_cts = 0;
674 } else if (decode_result == IFX_SPI_HEADER_F) {
675 dev_dbg(&ifx_dev->spi_dev->dev,
676 "ignore input: invalid header F");
680 ifx_dev->spi_slave_cts = cts;
682 actual_length = min((unsigned int)length,
683 ifx_dev->spi_msg.actual_length);
685 (ifx_dev->rx_buffer + IFX_SPI_HEADER_OVERHEAD),
687 &ifx_dev->rx_buffer[IFX_SPI_TRANSFER_SIZE]);
688 ifx_spi_insert_flip_string(
690 ifx_dev->rx_buffer + IFX_SPI_HEADER_OVERHEAD,
691 (size_t)actual_length);
694 dev_dbg(&ifx_dev->spi_dev->dev, "SPI transfer error %d",
695 ifx_dev->spi_msg.status);
699 if (ifx_dev->write_pending) {
700 ifx_dev->write_pending = 0;
701 local_write_pending = 1;
704 clear_bit(IFX_SPI_STATE_IO_IN_PROGRESS, &(ifx_dev->flags));
706 queue_length = kfifo_len(&ifx_dev->tx_fifo);
707 srdy = gpio_get_value(ifx_dev->gpio.srdy);
709 ifx_spi_power_state_clear(ifx_dev, IFX_SPI_POWER_SRDY);
711 /* schedule output if there is more to do */
712 if (test_and_clear_bit(IFX_SPI_STATE_IO_READY, &ifx_dev->flags))
713 tasklet_schedule(&ifx_dev->io_work_tasklet);
715 if (more || ifx_dev->spi_more || queue_length > 0 ||
716 local_write_pending) {
717 if (ifx_dev->spi_slave_cts) {
719 mrdy_assert(ifx_dev);
721 mrdy_assert(ifx_dev);
724 * poke line discipline driver if any for more data
725 * may or may not get more data to write
726 * for now, say not busy
728 ifx_spi_power_state_clear(ifx_dev,
729 IFX_SPI_POWER_DATA_PENDING);
730 tty_port_tty_wakeup(&ifx_dev->tty_port);
736 * ifx_spio_io - I/O tasklet
737 * @data: our SPI device
739 * Queue data for transmission if possible and then kick off the
742 static void ifx_spi_io(unsigned long data)
745 struct ifx_spi_device *ifx_dev = (struct ifx_spi_device *) data;
747 if (!test_and_set_bit(IFX_SPI_STATE_IO_IN_PROGRESS, &ifx_dev->flags) &&
748 test_bit(IFX_SPI_STATE_IO_AVAILABLE, &ifx_dev->flags)) {
749 if (ifx_dev->gpio.unack_srdy_int_nb > 0)
750 ifx_dev->gpio.unack_srdy_int_nb--;
752 ifx_spi_prepare_tx_buffer(ifx_dev);
754 spi_message_init(&ifx_dev->spi_msg);
755 INIT_LIST_HEAD(&ifx_dev->spi_msg.queue);
757 ifx_dev->spi_msg.context = ifx_dev;
758 ifx_dev->spi_msg.complete = ifx_spi_complete;
760 /* set up our spi transfer */
761 /* note len is BYTES, not transfers */
762 ifx_dev->spi_xfer.len = IFX_SPI_TRANSFER_SIZE;
763 ifx_dev->spi_xfer.cs_change = 0;
764 ifx_dev->spi_xfer.speed_hz = ifx_dev->spi_dev->max_speed_hz;
765 /* ifx_dev->spi_xfer.speed_hz = 390625; */
766 ifx_dev->spi_xfer.bits_per_word =
767 ifx_dev->spi_dev->bits_per_word;
769 ifx_dev->spi_xfer.tx_buf = ifx_dev->tx_buffer;
770 ifx_dev->spi_xfer.rx_buf = ifx_dev->rx_buffer;
775 if (ifx_dev->use_dma) {
776 ifx_dev->spi_msg.is_dma_mapped = 1;
777 ifx_dev->tx_dma = ifx_dev->tx_bus;
778 ifx_dev->rx_dma = ifx_dev->rx_bus;
779 ifx_dev->spi_xfer.tx_dma = ifx_dev->tx_dma;
780 ifx_dev->spi_xfer.rx_dma = ifx_dev->rx_dma;
782 ifx_dev->spi_msg.is_dma_mapped = 0;
783 ifx_dev->tx_dma = (dma_addr_t)0;
784 ifx_dev->rx_dma = (dma_addr_t)0;
785 ifx_dev->spi_xfer.tx_dma = (dma_addr_t)0;
786 ifx_dev->spi_xfer.rx_dma = (dma_addr_t)0;
789 spi_message_add_tail(&ifx_dev->spi_xfer, &ifx_dev->spi_msg);
791 /* Assert MRDY. This may have already been done by the write
794 mrdy_assert(ifx_dev);
796 retval = spi_async(ifx_dev->spi_dev, &ifx_dev->spi_msg);
798 clear_bit(IFX_SPI_STATE_IO_IN_PROGRESS,
800 tasklet_schedule(&ifx_dev->io_work_tasklet);
804 ifx_dev->write_pending = 1;
808 * ifx_spi_free_port - free up the tty side
809 * @ifx_dev: IFX device going away
811 * Unregister and free up a port when the device goes away
813 static void ifx_spi_free_port(struct ifx_spi_device *ifx_dev)
815 if (ifx_dev->tty_dev)
816 tty_unregister_device(tty_drv, ifx_dev->minor);
817 tty_port_destroy(&ifx_dev->tty_port);
818 kfifo_free(&ifx_dev->tx_fifo);
822 * ifx_spi_create_port - create a new port
823 * @ifx_dev: our spi device
825 * Allocate and initialise the tty port that goes with this interface
826 * and add it to the tty layer so that it can be opened.
828 static int ifx_spi_create_port(struct ifx_spi_device *ifx_dev)
831 struct tty_port *pport = &ifx_dev->tty_port;
833 spin_lock_init(&ifx_dev->fifo_lock);
834 lockdep_set_class_and_subclass(&ifx_dev->fifo_lock,
837 if (kfifo_alloc(&ifx_dev->tx_fifo, IFX_SPI_FIFO_SIZE, GFP_KERNEL)) {
842 tty_port_init(pport);
843 pport->ops = &ifx_tty_port_ops;
844 ifx_dev->minor = IFX_SPI_TTY_ID;
845 ifx_dev->tty_dev = tty_port_register_device(pport, tty_drv,
846 ifx_dev->minor, &ifx_dev->spi_dev->dev);
847 if (IS_ERR(ifx_dev->tty_dev)) {
848 dev_dbg(&ifx_dev->spi_dev->dev,
849 "%s: registering tty device failed", __func__);
850 ret = PTR_ERR(ifx_dev->tty_dev);
856 tty_port_destroy(pport);
858 ifx_spi_free_port(ifx_dev);
863 * ifx_spi_handle_srdy - handle SRDY
864 * @ifx_dev: device asserting SRDY
866 * Check our device state and see what we need to kick off when SRDY
867 * is asserted. This usually means killing the timer and firing off the
870 static void ifx_spi_handle_srdy(struct ifx_spi_device *ifx_dev)
872 if (test_bit(IFX_SPI_STATE_TIMER_PENDING, &ifx_dev->flags)) {
873 del_timer(&ifx_dev->spi_timer);
874 clear_bit(IFX_SPI_STATE_TIMER_PENDING, &ifx_dev->flags);
877 ifx_spi_power_state_set(ifx_dev, IFX_SPI_POWER_SRDY);
879 if (!test_bit(IFX_SPI_STATE_IO_IN_PROGRESS, &ifx_dev->flags))
880 tasklet_schedule(&ifx_dev->io_work_tasklet);
882 set_bit(IFX_SPI_STATE_IO_READY, &ifx_dev->flags);
886 * ifx_spi_srdy_interrupt - SRDY asserted
887 * @irq: our IRQ number
888 * @dev: our ifx device
890 * The modem asserted SRDY. Handle the srdy event
892 static irqreturn_t ifx_spi_srdy_interrupt(int irq, void *dev)
894 struct ifx_spi_device *ifx_dev = dev;
895 ifx_dev->gpio.unack_srdy_int_nb++;
896 ifx_spi_handle_srdy(ifx_dev);
901 * ifx_spi_reset_interrupt - Modem has changed reset state
902 * @irq: interrupt number
903 * @dev: our device pointer
905 * The modem has either entered or left reset state. Check the GPIO
908 * FIXME: review locking on MR_INPROGRESS versus
909 * parallel unsolicited reset/solicited reset
911 static irqreturn_t ifx_spi_reset_interrupt(int irq, void *dev)
913 struct ifx_spi_device *ifx_dev = dev;
914 int val = gpio_get_value(ifx_dev->gpio.reset_out);
915 int solreset = test_bit(MR_START, &ifx_dev->mdm_reset_state);
919 set_bit(MR_INPROGRESS, &ifx_dev->mdm_reset_state);
921 /* unsolicited reset */
922 tty_port_tty_hangup(&ifx_dev->tty_port, false);
926 clear_bit(MR_INPROGRESS, &ifx_dev->mdm_reset_state);
928 set_bit(MR_COMPLETE, &ifx_dev->mdm_reset_state);
929 wake_up(&ifx_dev->mdm_reset_wait);
936 * ifx_spi_free_device - free device
937 * @ifx_dev: device to free
939 * Free the IFX device
941 static void ifx_spi_free_device(struct ifx_spi_device *ifx_dev)
943 ifx_spi_free_port(ifx_dev);
944 dma_free_coherent(&ifx_dev->spi_dev->dev,
945 IFX_SPI_TRANSFER_SIZE,
948 dma_free_coherent(&ifx_dev->spi_dev->dev,
949 IFX_SPI_TRANSFER_SIZE,
955 * ifx_spi_reset - reset modem
956 * @ifx_dev: modem to reset
958 * Perform a reset on the modem
960 static int ifx_spi_reset(struct ifx_spi_device *ifx_dev)
964 * set up modem power, reset
966 * delays are required on some platforms for the modem
969 set_bit(MR_START, &ifx_dev->mdm_reset_state);
970 gpio_set_value(ifx_dev->gpio.po, 0);
971 gpio_set_value(ifx_dev->gpio.reset, 0);
973 gpio_set_value(ifx_dev->gpio.reset, 1);
975 gpio_set_value(ifx_dev->gpio.po, 1);
977 gpio_set_value(ifx_dev->gpio.po, 0);
978 ret = wait_event_timeout(ifx_dev->mdm_reset_wait,
979 test_bit(MR_COMPLETE,
980 &ifx_dev->mdm_reset_state),
983 dev_warn(&ifx_dev->spi_dev->dev, "Modem reset timeout: (state:%lx)",
984 ifx_dev->mdm_reset_state);
986 ifx_dev->mdm_reset_state = 0;
991 * ifx_spi_spi_probe - probe callback
992 * @spi: our possible matching SPI device
994 * Probe for a 6x60 modem on SPI bus. Perform any needed device and
998 * - Support for multiple devices
999 * - Split out MID specific GPIO handling eventually
1002 static int ifx_spi_spi_probe(struct spi_device *spi)
1006 struct ifx_modem_platform_data *pl_data;
1007 struct ifx_spi_device *ifx_dev;
1009 if (saved_ifx_dev) {
1010 dev_dbg(&spi->dev, "ignoring subsequent detection");
1014 pl_data = dev_get_platdata(&spi->dev);
1016 dev_err(&spi->dev, "missing platform data!");
1020 /* initialize structure to hold our device variables */
1021 ifx_dev = kzalloc(sizeof(struct ifx_spi_device), GFP_KERNEL);
1023 dev_err(&spi->dev, "spi device allocation failed");
1026 saved_ifx_dev = ifx_dev;
1027 ifx_dev->spi_dev = spi;
1028 clear_bit(IFX_SPI_STATE_IO_IN_PROGRESS, &ifx_dev->flags);
1029 spin_lock_init(&ifx_dev->write_lock);
1030 spin_lock_init(&ifx_dev->power_lock);
1031 ifx_dev->power_status = 0;
1032 init_timer(&ifx_dev->spi_timer);
1033 ifx_dev->spi_timer.function = ifx_spi_timeout;
1034 ifx_dev->spi_timer.data = (unsigned long)ifx_dev;
1035 ifx_dev->modem = pl_data->modem_type;
1036 ifx_dev->use_dma = pl_data->use_dma;
1037 ifx_dev->max_hz = pl_data->max_hz;
1038 /* initialize spi mode, etc */
1039 spi->max_speed_hz = ifx_dev->max_hz;
1040 spi->mode = IFX_SPI_MODE | (SPI_LOOP & spi->mode);
1041 spi->bits_per_word = spi_bpw;
1042 ret = spi_setup(spi);
1044 dev_err(&spi->dev, "SPI setup wasn't successful %d", ret);
1048 /* init swap_buf function according to word width configuration */
1049 if (spi->bits_per_word == 32)
1050 ifx_dev->swap_buf = swap_buf_32;
1051 else if (spi->bits_per_word == 16)
1052 ifx_dev->swap_buf = swap_buf_16;
1054 ifx_dev->swap_buf = swap_buf_8;
1056 /* ensure SPI protocol flags are initialized to enable transfer */
1057 ifx_dev->spi_more = 0;
1058 ifx_dev->spi_slave_cts = 0;
1060 /*initialize transfer and dma buffers */
1061 ifx_dev->tx_buffer = dma_alloc_coherent(ifx_dev->spi_dev->dev.parent,
1062 IFX_SPI_TRANSFER_SIZE,
1065 if (!ifx_dev->tx_buffer) {
1066 dev_err(&spi->dev, "DMA-TX buffer allocation failed");
1070 ifx_dev->rx_buffer = dma_alloc_coherent(ifx_dev->spi_dev->dev.parent,
1071 IFX_SPI_TRANSFER_SIZE,
1074 if (!ifx_dev->rx_buffer) {
1075 dev_err(&spi->dev, "DMA-RX buffer allocation failed");
1080 /* initialize waitq for modem reset */
1081 init_waitqueue_head(&ifx_dev->mdm_reset_wait);
1083 spi_set_drvdata(spi, ifx_dev);
1084 tasklet_init(&ifx_dev->io_work_tasklet, ifx_spi_io,
1085 (unsigned long)ifx_dev);
1087 set_bit(IFX_SPI_STATE_PRESENT, &ifx_dev->flags);
1089 /* create our tty port */
1090 ret = ifx_spi_create_port(ifx_dev);
1092 dev_err(&spi->dev, "create default tty port failed");
1096 ifx_dev->gpio.reset = pl_data->rst_pmu;
1097 ifx_dev->gpio.po = pl_data->pwr_on;
1098 ifx_dev->gpio.mrdy = pl_data->mrdy;
1099 ifx_dev->gpio.srdy = pl_data->srdy;
1100 ifx_dev->gpio.reset_out = pl_data->rst_out;
1102 dev_info(&spi->dev, "gpios %d, %d, %d, %d, %d",
1103 ifx_dev->gpio.reset, ifx_dev->gpio.po, ifx_dev->gpio.mrdy,
1104 ifx_dev->gpio.srdy, ifx_dev->gpio.reset_out);
1106 /* Configure gpios */
1107 ret = gpio_request(ifx_dev->gpio.reset, "ifxModem");
1109 dev_err(&spi->dev, "Unable to allocate GPIO%d (RESET)",
1110 ifx_dev->gpio.reset);
1113 ret += gpio_direction_output(ifx_dev->gpio.reset, 0);
1114 ret += gpio_export(ifx_dev->gpio.reset, 1);
1116 dev_err(&spi->dev, "Unable to configure GPIO%d (RESET)",
1117 ifx_dev->gpio.reset);
1122 ret = gpio_request(ifx_dev->gpio.po, "ifxModem");
1123 ret += gpio_direction_output(ifx_dev->gpio.po, 0);
1124 ret += gpio_export(ifx_dev->gpio.po, 1);
1126 dev_err(&spi->dev, "Unable to configure GPIO%d (ON)",
1132 ret = gpio_request(ifx_dev->gpio.mrdy, "ifxModem");
1134 dev_err(&spi->dev, "Unable to allocate GPIO%d (MRDY)",
1135 ifx_dev->gpio.mrdy);
1138 ret += gpio_export(ifx_dev->gpio.mrdy, 1);
1139 ret += gpio_direction_output(ifx_dev->gpio.mrdy, 0);
1141 dev_err(&spi->dev, "Unable to configure GPIO%d (MRDY)",
1142 ifx_dev->gpio.mrdy);
1147 ret = gpio_request(ifx_dev->gpio.srdy, "ifxModem");
1149 dev_err(&spi->dev, "Unable to allocate GPIO%d (SRDY)",
1150 ifx_dev->gpio.srdy);
1154 ret += gpio_export(ifx_dev->gpio.srdy, 1);
1155 ret += gpio_direction_input(ifx_dev->gpio.srdy);
1157 dev_err(&spi->dev, "Unable to configure GPIO%d (SRDY)",
1158 ifx_dev->gpio.srdy);
1163 ret = gpio_request(ifx_dev->gpio.reset_out, "ifxModem");
1165 dev_err(&spi->dev, "Unable to allocate GPIO%d (RESET_OUT)",
1166 ifx_dev->gpio.reset_out);
1169 ret += gpio_export(ifx_dev->gpio.reset_out, 1);
1170 ret += gpio_direction_input(ifx_dev->gpio.reset_out);
1172 dev_err(&spi->dev, "Unable to configure GPIO%d (RESET_OUT)",
1173 ifx_dev->gpio.reset_out);
1178 ret = request_irq(gpio_to_irq(ifx_dev->gpio.reset_out),
1179 ifx_spi_reset_interrupt,
1180 IRQF_TRIGGER_RISING|IRQF_TRIGGER_FALLING, DRVNAME,
1183 dev_err(&spi->dev, "Unable to get irq %x\n",
1184 gpio_to_irq(ifx_dev->gpio.reset_out));
1188 ret = ifx_spi_reset(ifx_dev);
1190 ret = request_irq(gpio_to_irq(ifx_dev->gpio.srdy),
1191 ifx_spi_srdy_interrupt, IRQF_TRIGGER_RISING, DRVNAME,
1194 dev_err(&spi->dev, "Unable to get irq %x",
1195 gpio_to_irq(ifx_dev->gpio.srdy));
1199 /* set pm runtime power state and register with power system */
1200 pm_runtime_set_active(&spi->dev);
1201 pm_runtime_enable(&spi->dev);
1203 /* handle case that modem is already signaling SRDY */
1204 /* no outgoing tty open at this point, this just satisfies the
1205 * modem's read and should reset communication properly
1207 srdy = gpio_get_value(ifx_dev->gpio.srdy);
1210 mrdy_assert(ifx_dev);
1211 ifx_spi_handle_srdy(ifx_dev);
1213 mrdy_set_low(ifx_dev);
1217 free_irq(gpio_to_irq(ifx_dev->gpio.reset_out), ifx_dev);
1219 gpio_free(ifx_dev->gpio.srdy);
1221 gpio_free(ifx_dev->gpio.mrdy);
1223 gpio_free(ifx_dev->gpio.reset);
1225 gpio_free(ifx_dev->gpio.po);
1227 gpio_free(ifx_dev->gpio.reset_out);
1229 ifx_spi_free_device(ifx_dev);
1230 saved_ifx_dev = NULL;
1235 * ifx_spi_spi_remove - SPI device was removed
1238 * FIXME: We should be shutting the device down here not in
1239 * the module unload path.
1242 static int ifx_spi_spi_remove(struct spi_device *spi)
1244 struct ifx_spi_device *ifx_dev = spi_get_drvdata(spi);
1246 tasklet_kill(&ifx_dev->io_work_tasklet);
1248 pm_runtime_disable(&spi->dev);
1251 free_irq(gpio_to_irq(ifx_dev->gpio.reset_out), ifx_dev);
1252 free_irq(gpio_to_irq(ifx_dev->gpio.srdy), ifx_dev);
1254 gpio_free(ifx_dev->gpio.srdy);
1255 gpio_free(ifx_dev->gpio.mrdy);
1256 gpio_free(ifx_dev->gpio.reset);
1257 gpio_free(ifx_dev->gpio.po);
1258 gpio_free(ifx_dev->gpio.reset_out);
1260 /* free allocations */
1261 ifx_spi_free_device(ifx_dev);
1263 saved_ifx_dev = NULL;
1268 * ifx_spi_spi_shutdown - called on SPI shutdown
1271 * No action needs to be taken here
1274 static void ifx_spi_spi_shutdown(struct spi_device *spi)
1276 struct ifx_spi_device *ifx_dev = spi_get_drvdata(spi);
1278 ifx_modem_power_off(ifx_dev);
1282 * various suspends and resumes have nothing to do
1283 * no hardware to save state for
1287 * ifx_spi_pm_suspend - suspend modem on system suspend
1288 * @dev: device being suspended
1290 * Suspend the modem. No action needed on Intel MID platforms, may
1291 * need extending for other systems.
1293 static int ifx_spi_pm_suspend(struct device *dev)
1299 * ifx_spi_pm_resume - resume modem on system resume
1300 * @dev: device being suspended
1302 * Allow the modem to resume. No action needed.
1304 * FIXME: do we need to reset anything here ?
1306 static int ifx_spi_pm_resume(struct device *dev)
1312 * ifx_spi_pm_runtime_resume - suspend modem
1313 * @dev: device being suspended
1315 * Allow the modem to resume. No action needed.
1317 static int ifx_spi_pm_runtime_resume(struct device *dev)
1323 * ifx_spi_pm_runtime_suspend - suspend modem
1324 * @dev: device being suspended
1326 * Allow the modem to suspend and thus suspend to continue up the
1329 static int ifx_spi_pm_runtime_suspend(struct device *dev)
1335 * ifx_spi_pm_runtime_idle - check if modem idle
1338 * Check conditions and queue runtime suspend if idle.
1340 static int ifx_spi_pm_runtime_idle(struct device *dev)
1342 struct spi_device *spi = to_spi_device(dev);
1343 struct ifx_spi_device *ifx_dev = spi_get_drvdata(spi);
1345 if (!ifx_dev->power_status)
1346 pm_runtime_suspend(dev);
1351 static const struct dev_pm_ops ifx_spi_pm = {
1352 .resume = ifx_spi_pm_resume,
1353 .suspend = ifx_spi_pm_suspend,
1354 .runtime_resume = ifx_spi_pm_runtime_resume,
1355 .runtime_suspend = ifx_spi_pm_runtime_suspend,
1356 .runtime_idle = ifx_spi_pm_runtime_idle
1359 static const struct spi_device_id ifx_id_table[] = {
1364 MODULE_DEVICE_TABLE(spi, ifx_id_table);
1366 /* spi operations */
1367 static struct spi_driver ifx_spi_driver = {
1372 .probe = ifx_spi_spi_probe,
1373 .shutdown = ifx_spi_spi_shutdown,
1374 .remove = ifx_spi_spi_remove,
1375 .id_table = ifx_id_table
1379 * ifx_spi_exit - module exit
1381 * Unload the module.
1384 static void __exit ifx_spi_exit(void)
1387 spi_unregister_driver(&ifx_spi_driver);
1388 tty_unregister_driver(tty_drv);
1389 put_tty_driver(tty_drv);
1390 unregister_reboot_notifier(&ifx_modem_reboot_notifier_block);
1394 * ifx_spi_init - module entry point
1396 * Initialise the SPI and tty interfaces for the IFX SPI driver
1397 * We need to initialize upper-edge spi driver after the tty
1398 * driver because otherwise the spi probe will race
1401 static int __init ifx_spi_init(void)
1405 tty_drv = alloc_tty_driver(1);
1407 pr_err("%s: alloc_tty_driver failed", DRVNAME);
1411 tty_drv->driver_name = DRVNAME;
1412 tty_drv->name = TTYNAME;
1413 tty_drv->minor_start = IFX_SPI_TTY_ID;
1414 tty_drv->type = TTY_DRIVER_TYPE_SERIAL;
1415 tty_drv->subtype = SERIAL_TYPE_NORMAL;
1416 tty_drv->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
1417 tty_drv->init_termios = tty_std_termios;
1419 tty_set_operations(tty_drv, &ifx_spi_serial_ops);
1421 result = tty_register_driver(tty_drv);
1423 pr_err("%s: tty_register_driver failed(%d)",
1428 result = spi_register_driver(&ifx_spi_driver);
1430 pr_err("%s: spi_register_driver failed(%d)",
1435 result = register_reboot_notifier(&ifx_modem_reboot_notifier_block);
1437 pr_err("%s: register ifx modem reboot notifier failed(%d)",
1444 spi_unregister_driver(&ifx_spi_driver);
1446 tty_unregister_driver(tty_drv);
1448 put_tty_driver(tty_drv);
1453 module_init(ifx_spi_init);
1454 module_exit(ifx_spi_exit);
1456 MODULE_AUTHOR("Intel");
1457 MODULE_DESCRIPTION("IFX6x60 spi driver");
1458 MODULE_LICENSE("GPL");
1459 MODULE_INFO(Version, "0.1-IFX6x60");