1 /****************************************************************************
2 *
3 * Driver for the IFX 6x60 spi modem.
4 *
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>
9 *
10 * Copyright (C) 2009, 2010 Intel Corp
11 * Russ Gorby <russ.gorby@intel.com>
12 *
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.
16 *
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.
21 *
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,
25 * USA
26 *
27 * Driver modified by Intel from Option gtm501l_spi.c
28 *
29 * Notes
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.
37 *
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>
52 #include <linux/fs.h>
53 #include <linux/ip.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/pm.h>
60 #include <linux/pm_runtime.h>
61 #include <linux/spi/ifx_modem.h>
62 #include <linux/delay.h>
63 #include <linux/reboot.h>
64
65 #include "ifx6x60.h"
66
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)
75
76 #define PO_POST_DELAY 200
77 #define IFX_MDM_RST_PMU 4
78
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);
84
85 /* local variables */
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;
90
91 static struct notifier_block ifx_modem_reboot_notifier_block = {
92 .notifier_call = ifx_modem_reboot_callback,
93 };
94
ifx_modem_power_off(struct ifx_spi_device * ifx_dev)95 static int ifx_modem_power_off(struct ifx_spi_device *ifx_dev)
96 {
97 gpio_set_value(IFX_MDM_RST_PMU, 1);
98 msleep(PO_POST_DELAY);
99
100 return 0;
101 }
102
ifx_modem_reboot_callback(struct notifier_block * nfb,unsigned long event,void * data)103 static int ifx_modem_reboot_callback(struct notifier_block *nfb,
104 unsigned long event, void *data)
105 {
106 if (saved_ifx_dev)
107 ifx_modem_power_off(saved_ifx_dev);
108 else
109 pr_warn("no ifx modem active;\n");
110
111 return NOTIFY_OK;
112 }
113
114 /* GPIO/GPE settings */
115
116 /**
117 * mrdy_set_high - set MRDY GPIO
118 * @ifx: device we are controlling
119 *
120 */
mrdy_set_high(struct ifx_spi_device * ifx)121 static inline void mrdy_set_high(struct ifx_spi_device *ifx)
122 {
123 gpio_set_value(ifx->gpio.mrdy, 1);
124 }
125
126 /**
127 * mrdy_set_low - clear MRDY GPIO
128 * @ifx: device we are controlling
129 *
130 */
mrdy_set_low(struct ifx_spi_device * ifx)131 static inline void mrdy_set_low(struct ifx_spi_device *ifx)
132 {
133 gpio_set_value(ifx->gpio.mrdy, 0);
134 }
135
136 /**
137 * ifx_spi_power_state_set
138 * @ifx_dev: our SPI device
139 * @val: bits to set
140 *
141 * Set bit in power status and signal power system if status becomes non-0
142 */
143 static void
ifx_spi_power_state_set(struct ifx_spi_device * ifx_dev,unsigned char val)144 ifx_spi_power_state_set(struct ifx_spi_device *ifx_dev, unsigned char val)
145 {
146 unsigned long flags;
147
148 spin_lock_irqsave(&ifx_dev->power_lock, flags);
149
150 /*
151 * if power status is already non-0, just update, else
152 * tell power system
153 */
154 if (!ifx_dev->power_status)
155 pm_runtime_get(&ifx_dev->spi_dev->dev);
156 ifx_dev->power_status |= val;
157
158 spin_unlock_irqrestore(&ifx_dev->power_lock, flags);
159 }
160
161 /**
162 * ifx_spi_power_state_clear - clear power bit
163 * @ifx_dev: our SPI device
164 * @val: bits to clear
165 *
166 * clear bit in power status and signal power system if status becomes 0
167 */
168 static void
ifx_spi_power_state_clear(struct ifx_spi_device * ifx_dev,unsigned char val)169 ifx_spi_power_state_clear(struct ifx_spi_device *ifx_dev, unsigned char val)
170 {
171 unsigned long flags;
172
173 spin_lock_irqsave(&ifx_dev->power_lock, flags);
174
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);
179 }
180
181 spin_unlock_irqrestore(&ifx_dev->power_lock, flags);
182 }
183
184 /**
185 * swap_buf_8
186 * @buf: our buffer
187 * @len : number of bytes (not words) in the buffer
188 * @end: end of buffer
189 *
190 * Swap the contents of a buffer into big endian format
191 */
swap_buf_8(unsigned char * buf,int len,void * end)192 static inline void swap_buf_8(unsigned char *buf, int len, void *end)
193 {
194 /* don't swap buffer if SPI word width is 8 bits */
195 return;
196 }
197
198 /**
199 * swap_buf_16
200 * @buf: our buffer
201 * @len : number of bytes (not words) in the buffer
202 * @end: end of buffer
203 *
204 * Swap the contents of a buffer into big endian format
205 */
swap_buf_16(unsigned char * buf,int len,void * end)206 static inline void swap_buf_16(unsigned char *buf, int len, void *end)
207 {
208 int n;
209
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)!",
214 &buf_16[len], end);
215 return;
216 }
217 for (n = 0; n < len; n++) {
218 *buf_16 = cpu_to_be16(*buf_16);
219 buf_16++;
220 }
221 }
222
223 /**
224 * swap_buf_32
225 * @buf: our buffer
226 * @len : number of bytes (not words) in the buffer
227 * @end: end of buffer
228 *
229 * Swap the contents of a buffer into big endian format
230 */
swap_buf_32(unsigned char * buf,int len,void * end)231 static inline void swap_buf_32(unsigned char *buf, int len, void *end)
232 {
233 int n;
234
235 u32 *buf_32 = (u32 *)buf;
236 len = (len + 3) >> 2;
237
238 if ((void *)&buf_32[len] > end) {
239 pr_err("swap_buf_32: swap exceeds boundary (%p > %p)!\n",
240 &buf_32[len], end);
241 return;
242 }
243 for (n = 0; n < len; n++) {
244 *buf_32 = cpu_to_be32(*buf_32);
245 buf_32++;
246 }
247 }
248
249 /**
250 * mrdy_assert - assert MRDY line
251 * @ifx_dev: our SPI device
252 *
253 * Assert mrdy and set timer to wait for SRDY interrupt, if SRDY is low
254 * now.
255 *
256 * FIXME: Can SRDY even go high as we are running this code ?
257 */
mrdy_assert(struct ifx_spi_device * ifx_dev)258 static void mrdy_assert(struct ifx_spi_device *ifx_dev)
259 {
260 int val = gpio_get_value(ifx_dev->gpio.srdy);
261 if (!val) {
262 if (!test_and_set_bit(IFX_SPI_STATE_TIMER_PENDING,
263 &ifx_dev->flags)) {
264 mod_timer(&ifx_dev->spi_timer,jiffies + IFX_SPI_TIMEOUT_SEC*HZ);
265
266 }
267 }
268 ifx_spi_power_state_set(ifx_dev, IFX_SPI_POWER_DATA_PENDING);
269 mrdy_set_high(ifx_dev);
270 }
271
272 /**
273 * ifx_spi_timeout - SPI timeout
274 * @arg: our SPI device
275 *
276 * The SPI has timed out: hang up the tty. Users will then see a hangup
277 * and error events.
278 */
ifx_spi_timeout(unsigned long arg)279 static void ifx_spi_timeout(unsigned long arg)
280 {
281 struct ifx_spi_device *ifx_dev = (struct ifx_spi_device *)arg;
282
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);
287 }
288
289 /* char/tty operations */
290
291 /**
292 * ifx_spi_tiocmget - get modem lines
293 * @tty: our tty device
294 * @filp: file handle issuing the request
295 *
296 * Map the signal state into Linux modem flags and report the value
297 * in Linux terms
298 */
ifx_spi_tiocmget(struct tty_struct * tty)299 static int ifx_spi_tiocmget(struct tty_struct *tty)
300 {
301 unsigned int value;
302 struct ifx_spi_device *ifx_dev = tty->driver_data;
303
304 value =
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);
311 return value;
312 }
313
314 /**
315 * ifx_spi_tiocmset - set modem bits
316 * @tty: the tty structure
317 * @set: bits to set
318 * @clear: bits to clear
319 *
320 * The IFX6x60 only supports DTR and RTS. Set them accordingly
321 * and flag that an update to the modem is needed.
322 *
323 * FIXME: do we need to kick the tranfers when we do this ?
324 */
ifx_spi_tiocmset(struct tty_struct * tty,unsigned int set,unsigned int clear)325 static int ifx_spi_tiocmset(struct tty_struct *tty,
326 unsigned int set, unsigned int clear)
327 {
328 struct ifx_spi_device *ifx_dev = tty->driver_data;
329
330 if (set & TIOCM_RTS)
331 set_bit(IFX_SPI_RTS, &ifx_dev->signal_state);
332 if (set & TIOCM_DTR)
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);
338
339 set_bit(IFX_SPI_UPDATE, &ifx_dev->signal_state);
340 return 0;
341 }
342
343 /**
344 * ifx_spi_open - called on tty open
345 * @tty: our tty device
346 * @filp: file handle being associated with the tty
347 *
348 * Open the tty interface. We let the tty_port layer do all the work
349 * for us.
350 *
351 * FIXME: Remove single device assumption and saved_ifx_dev
352 */
ifx_spi_open(struct tty_struct * tty,struct file * filp)353 static int ifx_spi_open(struct tty_struct *tty, struct file *filp)
354 {
355 return tty_port_open(&saved_ifx_dev->tty_port, tty, filp);
356 }
357
358 /**
359 * ifx_spi_close - called when our tty closes
360 * @tty: the tty being closed
361 * @filp: the file handle being closed
362 *
363 * Perform the close of the tty. We use the tty_port layer to do all
364 * our hard work.
365 */
ifx_spi_close(struct tty_struct * tty,struct file * filp)366 static void ifx_spi_close(struct tty_struct *tty, struct file *filp)
367 {
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 ? */
371 }
372
373 /**
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
379 *
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.
383 *
384 * FIXME: endianness
385 */
ifx_spi_decode_spi_header(unsigned char * buffer,int * length,unsigned char * more,unsigned char * received_cts)386 static int ifx_spi_decode_spi_header(unsigned char *buffer, int *length,
387 unsigned char *more, unsigned char *received_cts)
388 {
389 u16 h1;
390 u16 h2;
391 u16 *in_buffer = (u16 *)buffer;
392
393 h1 = *in_buffer;
394 h2 = *(in_buffer+1);
395
396 if (h1 == 0 && h2 == 0) {
397 *received_cts = 0;
398 return IFX_SPI_HEADER_0;
399 } else if (h1 == 0xffff && h2 == 0xffff) {
400 /* spi_slave_cts remains as it was */
401 return IFX_SPI_HEADER_F;
402 }
403
404 *length = h1 & 0xfff; /* upper bits of byte are flags */
405 *more = (buffer[1] >> IFX_SPI_MORE_BIT) & 1;
406 *received_cts = (buffer[3] >> IFX_SPI_CTS_BIT) & 1;
407 return 0;
408 }
409
410 /**
411 * ifx_setup_spi_header - set header fields
412 * @txbuffer: pointer to start of SPI buffer
413 * @tx_count: bytes
414 * @more: indicate if more to follow
415 *
416 * Format up an SPI header for a transfer
417 *
418 * FIXME: endianness?
419 */
ifx_spi_setup_spi_header(unsigned char * txbuffer,int tx_count,unsigned char more)420 static void ifx_spi_setup_spi_header(unsigned char *txbuffer, int tx_count,
421 unsigned char more)
422 {
423 *(u16 *)(txbuffer) = tx_count;
424 *(u16 *)(txbuffer+2) = IFX_SPI_PAYLOAD_SIZE;
425 txbuffer[1] |= (more << IFX_SPI_MORE_BIT) & IFX_SPI_MORE_MASK;
426 }
427
428 /**
429 * ifx_spi_prepare_tx_buffer - prepare transmit frame
430 * @ifx_dev: our SPI device
431 *
432 * The transmit buffr needs a header and various other bits of
433 * information followed by as much data as we can pull from the FIFO
434 * and transfer. This function formats up a suitable buffer in the
435 * ifx_dev->tx_buffer
436 *
437 * FIXME: performance - should we wake the tty when the queue is half
438 * empty ?
439 */
ifx_spi_prepare_tx_buffer(struct ifx_spi_device * ifx_dev)440 static int ifx_spi_prepare_tx_buffer(struct ifx_spi_device *ifx_dev)
441 {
442 int temp_count;
443 int queue_length;
444 int tx_count;
445 unsigned char *tx_buffer;
446
447 tx_buffer = ifx_dev->tx_buffer;
448
449 /* make room for required SPI header */
450 tx_buffer += IFX_SPI_HEADER_OVERHEAD;
451 tx_count = IFX_SPI_HEADER_OVERHEAD;
452
453 /* clear to signal no more data if this turns out to be the
454 * last buffer sent in a sequence */
455 ifx_dev->spi_more = 0;
456
457 /* if modem cts is set, just send empty buffer */
458 if (!ifx_dev->spi_slave_cts) {
459 /* see if there's tx data */
460 queue_length = kfifo_len(&ifx_dev->tx_fifo);
461 if (queue_length != 0) {
462 /* data to mux -- see if there's room for it */
463 temp_count = min(queue_length, IFX_SPI_PAYLOAD_SIZE);
464 temp_count = kfifo_out_locked(&ifx_dev->tx_fifo,
465 tx_buffer, temp_count,
466 &ifx_dev->fifo_lock);
467
468 /* update buffer pointer and data count in message */
469 tx_buffer += temp_count;
470 tx_count += temp_count;
471 if (temp_count == queue_length)
472 /* poke port to get more data */
473 tty_port_tty_wakeup(&ifx_dev->tty_port);
474 else /* more data in port, use next SPI message */
475 ifx_dev->spi_more = 1;
476 }
477 }
478 /* have data and info for header -- set up SPI header in buffer */
479 /* spi header needs payload size, not entire buffer size */
480 ifx_spi_setup_spi_header(ifx_dev->tx_buffer,
481 tx_count-IFX_SPI_HEADER_OVERHEAD,
482 ifx_dev->spi_more);
483 /* swap actual data in the buffer */
484 ifx_dev->swap_buf((ifx_dev->tx_buffer), tx_count,
485 &ifx_dev->tx_buffer[IFX_SPI_TRANSFER_SIZE]);
486 return tx_count;
487 }
488
489 /**
490 * ifx_spi_write - line discipline write
491 * @tty: our tty device
492 * @buf: pointer to buffer to write (kernel space)
493 * @count: size of buffer
494 *
495 * Write the characters we have been given into the FIFO. If the device
496 * is not active then activate it, when the SRDY line is asserted back
497 * this will commence I/O
498 */
ifx_spi_write(struct tty_struct * tty,const unsigned char * buf,int count)499 static int ifx_spi_write(struct tty_struct *tty, const unsigned char *buf,
500 int count)
501 {
502 struct ifx_spi_device *ifx_dev = tty->driver_data;
503 unsigned char *tmp_buf = (unsigned char *)buf;
504 unsigned long flags;
505 bool is_fifo_empty;
506 int tx_count;
507
508 spin_lock_irqsave(&ifx_dev->fifo_lock, flags);
509 is_fifo_empty = kfifo_is_empty(&ifx_dev->tx_fifo);
510 tx_count = kfifo_in(&ifx_dev->tx_fifo, tmp_buf, count);
511 spin_unlock_irqrestore(&ifx_dev->fifo_lock, flags);
512 if (is_fifo_empty)
513 mrdy_assert(ifx_dev);
514
515 return tx_count;
516 }
517
518 /**
519 * ifx_spi_chars_in_buffer - line discipline helper
520 * @tty: our tty device
521 *
522 * Report how much data we can accept before we drop bytes. As we use
523 * a simple FIFO this is nice and easy.
524 */
ifx_spi_write_room(struct tty_struct * tty)525 static int ifx_spi_write_room(struct tty_struct *tty)
526 {
527 struct ifx_spi_device *ifx_dev = tty->driver_data;
528 return IFX_SPI_FIFO_SIZE - kfifo_len(&ifx_dev->tx_fifo);
529 }
530
531 /**
532 * ifx_spi_chars_in_buffer - line discipline helper
533 * @tty: our tty device
534 *
535 * Report how many characters we have buffered. In our case this is the
536 * number of bytes sitting in our transmit FIFO.
537 */
ifx_spi_chars_in_buffer(struct tty_struct * tty)538 static int ifx_spi_chars_in_buffer(struct tty_struct *tty)
539 {
540 struct ifx_spi_device *ifx_dev = tty->driver_data;
541 return kfifo_len(&ifx_dev->tx_fifo);
542 }
543
544 /**
545 * ifx_port_hangup
546 * @port: our tty port
547 *
548 * tty port hang up. Called when tty_hangup processing is invoked either
549 * by loss of carrier, or by software (eg vhangup). Serialized against
550 * activate/shutdown by the tty layer.
551 */
ifx_spi_hangup(struct tty_struct * tty)552 static void ifx_spi_hangup(struct tty_struct *tty)
553 {
554 struct ifx_spi_device *ifx_dev = tty->driver_data;
555 tty_port_hangup(&ifx_dev->tty_port);
556 }
557
558 /**
559 * ifx_port_activate
560 * @port: our tty port
561 *
562 * tty port activate method - called for first open. Serialized
563 * with hangup and shutdown by the tty layer.
564 */
ifx_port_activate(struct tty_port * port,struct tty_struct * tty)565 static int ifx_port_activate(struct tty_port *port, struct tty_struct *tty)
566 {
567 struct ifx_spi_device *ifx_dev =
568 container_of(port, struct ifx_spi_device, tty_port);
569
570 /* clear any old data; can't do this in 'close' */
571 kfifo_reset(&ifx_dev->tx_fifo);
572
573 /* clear any flag which may be set in port shutdown procedure */
574 clear_bit(IFX_SPI_STATE_IO_IN_PROGRESS, &ifx_dev->flags);
575 clear_bit(IFX_SPI_STATE_IO_READY, &ifx_dev->flags);
576
577 /* put port data into this tty */
578 tty->driver_data = ifx_dev;
579
580 /* allows flip string push from int context */
581 port->low_latency = 1;
582
583 /* set flag to allows data transfer */
584 set_bit(IFX_SPI_STATE_IO_AVAILABLE, &ifx_dev->flags);
585
586 return 0;
587 }
588
589 /**
590 * ifx_port_shutdown
591 * @port: our tty port
592 *
593 * tty port shutdown method - called for last port close. Serialized
594 * with hangup and activate by the tty layer.
595 */
ifx_port_shutdown(struct tty_port * port)596 static void ifx_port_shutdown(struct tty_port *port)
597 {
598 struct ifx_spi_device *ifx_dev =
599 container_of(port, struct ifx_spi_device, tty_port);
600
601 clear_bit(IFX_SPI_STATE_IO_AVAILABLE, &ifx_dev->flags);
602 mrdy_set_low(ifx_dev);
603 del_timer(&ifx_dev->spi_timer);
604 clear_bit(IFX_SPI_STATE_TIMER_PENDING, &ifx_dev->flags);
605 tasklet_kill(&ifx_dev->io_work_tasklet);
606 }
607
608 static const struct tty_port_operations ifx_tty_port_ops = {
609 .activate = ifx_port_activate,
610 .shutdown = ifx_port_shutdown,
611 };
612
613 static const struct tty_operations ifx_spi_serial_ops = {
614 .open = ifx_spi_open,
615 .close = ifx_spi_close,
616 .write = ifx_spi_write,
617 .hangup = ifx_spi_hangup,
618 .write_room = ifx_spi_write_room,
619 .chars_in_buffer = ifx_spi_chars_in_buffer,
620 .tiocmget = ifx_spi_tiocmget,
621 .tiocmset = ifx_spi_tiocmset,
622 };
623
624 /**
625 * ifx_spi_insert_fip_string - queue received data
626 * @ifx_ser: our SPI device
627 * @chars: buffer we have received
628 * @size: number of chars reeived
629 *
630 * Queue bytes to the tty assuming the tty side is currently open. If
631 * not the discard the data.
632 */
ifx_spi_insert_flip_string(struct ifx_spi_device * ifx_dev,unsigned char * chars,size_t size)633 static void ifx_spi_insert_flip_string(struct ifx_spi_device *ifx_dev,
634 unsigned char *chars, size_t size)
635 {
636 tty_insert_flip_string(&ifx_dev->tty_port, chars, size);
637 tty_flip_buffer_push(&ifx_dev->tty_port);
638 }
639
640 /**
641 * ifx_spi_complete - SPI transfer completed
642 * @ctx: our SPI device
643 *
644 * An SPI transfer has completed. Process any received data and kick off
645 * any further transmits we can commence.
646 */
ifx_spi_complete(void * ctx)647 static void ifx_spi_complete(void *ctx)
648 {
649 struct ifx_spi_device *ifx_dev = ctx;
650 int length;
651 int actual_length;
652 unsigned char more;
653 unsigned char cts;
654 int local_write_pending = 0;
655 int queue_length;
656 int srdy;
657 int decode_result;
658
659 mrdy_set_low(ifx_dev);
660
661 if (!ifx_dev->spi_msg.status) {
662 /* check header validity, get comm flags */
663 ifx_dev->swap_buf(ifx_dev->rx_buffer, IFX_SPI_HEADER_OVERHEAD,
664 &ifx_dev->rx_buffer[IFX_SPI_HEADER_OVERHEAD]);
665 decode_result = ifx_spi_decode_spi_header(ifx_dev->rx_buffer,
666 &length, &more, &cts);
667 if (decode_result == IFX_SPI_HEADER_0) {
668 dev_dbg(&ifx_dev->spi_dev->dev,
669 "ignore input: invalid header 0");
670 ifx_dev->spi_slave_cts = 0;
671 goto complete_exit;
672 } else if (decode_result == IFX_SPI_HEADER_F) {
673 dev_dbg(&ifx_dev->spi_dev->dev,
674 "ignore input: invalid header F");
675 goto complete_exit;
676 }
677
678 ifx_dev->spi_slave_cts = cts;
679
680 actual_length = min((unsigned int)length,
681 ifx_dev->spi_msg.actual_length);
682 ifx_dev->swap_buf(
683 (ifx_dev->rx_buffer + IFX_SPI_HEADER_OVERHEAD),
684 actual_length,
685 &ifx_dev->rx_buffer[IFX_SPI_TRANSFER_SIZE]);
686 ifx_spi_insert_flip_string(
687 ifx_dev,
688 ifx_dev->rx_buffer + IFX_SPI_HEADER_OVERHEAD,
689 (size_t)actual_length);
690 } else {
691 dev_dbg(&ifx_dev->spi_dev->dev, "SPI transfer error %d",
692 ifx_dev->spi_msg.status);
693 }
694
695 complete_exit:
696 if (ifx_dev->write_pending) {
697 ifx_dev->write_pending = 0;
698 local_write_pending = 1;
699 }
700
701 clear_bit(IFX_SPI_STATE_IO_IN_PROGRESS, &(ifx_dev->flags));
702
703 queue_length = kfifo_len(&ifx_dev->tx_fifo);
704 srdy = gpio_get_value(ifx_dev->gpio.srdy);
705 if (!srdy)
706 ifx_spi_power_state_clear(ifx_dev, IFX_SPI_POWER_SRDY);
707
708 /* schedule output if there is more to do */
709 if (test_and_clear_bit(IFX_SPI_STATE_IO_READY, &ifx_dev->flags))
710 tasklet_schedule(&ifx_dev->io_work_tasklet);
711 else {
712 if (more || ifx_dev->spi_more || queue_length > 0 ||
713 local_write_pending) {
714 if (ifx_dev->spi_slave_cts) {
715 if (more)
716 mrdy_assert(ifx_dev);
717 } else
718 mrdy_assert(ifx_dev);
719 } else {
720 /*
721 * poke line discipline driver if any for more data
722 * may or may not get more data to write
723 * for now, say not busy
724 */
725 ifx_spi_power_state_clear(ifx_dev,
726 IFX_SPI_POWER_DATA_PENDING);
727 tty_port_tty_wakeup(&ifx_dev->tty_port);
728 }
729 }
730 }
731
732 /**
733 * ifx_spio_io - I/O tasklet
734 * @data: our SPI device
735 *
736 * Queue data for transmission if possible and then kick off the
737 * transfer.
738 */
ifx_spi_io(unsigned long data)739 static void ifx_spi_io(unsigned long data)
740 {
741 int retval;
742 struct ifx_spi_device *ifx_dev = (struct ifx_spi_device *) data;
743
744 if (!test_and_set_bit(IFX_SPI_STATE_IO_IN_PROGRESS, &ifx_dev->flags) &&
745 test_bit(IFX_SPI_STATE_IO_AVAILABLE, &ifx_dev->flags)) {
746 if (ifx_dev->gpio.unack_srdy_int_nb > 0)
747 ifx_dev->gpio.unack_srdy_int_nb--;
748
749 ifx_spi_prepare_tx_buffer(ifx_dev);
750
751 spi_message_init(&ifx_dev->spi_msg);
752 INIT_LIST_HEAD(&ifx_dev->spi_msg.queue);
753
754 ifx_dev->spi_msg.context = ifx_dev;
755 ifx_dev->spi_msg.complete = ifx_spi_complete;
756
757 /* set up our spi transfer */
758 /* note len is BYTES, not transfers */
759 ifx_dev->spi_xfer.len = IFX_SPI_TRANSFER_SIZE;
760 ifx_dev->spi_xfer.cs_change = 0;
761 ifx_dev->spi_xfer.speed_hz = ifx_dev->spi_dev->max_speed_hz;
762 /* ifx_dev->spi_xfer.speed_hz = 390625; */
763 ifx_dev->spi_xfer.bits_per_word =
764 ifx_dev->spi_dev->bits_per_word;
765
766 ifx_dev->spi_xfer.tx_buf = ifx_dev->tx_buffer;
767 ifx_dev->spi_xfer.rx_buf = ifx_dev->rx_buffer;
768
769 /*
770 * setup dma pointers
771 */
772 if (ifx_dev->use_dma) {
773 ifx_dev->spi_msg.is_dma_mapped = 1;
774 ifx_dev->tx_dma = ifx_dev->tx_bus;
775 ifx_dev->rx_dma = ifx_dev->rx_bus;
776 ifx_dev->spi_xfer.tx_dma = ifx_dev->tx_dma;
777 ifx_dev->spi_xfer.rx_dma = ifx_dev->rx_dma;
778 } else {
779 ifx_dev->spi_msg.is_dma_mapped = 0;
780 ifx_dev->tx_dma = (dma_addr_t)0;
781 ifx_dev->rx_dma = (dma_addr_t)0;
782 ifx_dev->spi_xfer.tx_dma = (dma_addr_t)0;
783 ifx_dev->spi_xfer.rx_dma = (dma_addr_t)0;
784 }
785
786 spi_message_add_tail(&ifx_dev->spi_xfer, &ifx_dev->spi_msg);
787
788 /* Assert MRDY. This may have already been done by the write
789 * routine.
790 */
791 mrdy_assert(ifx_dev);
792
793 retval = spi_async(ifx_dev->spi_dev, &ifx_dev->spi_msg);
794 if (retval) {
795 clear_bit(IFX_SPI_STATE_IO_IN_PROGRESS,
796 &ifx_dev->flags);
797 tasklet_schedule(&ifx_dev->io_work_tasklet);
798 return;
799 }
800 } else
801 ifx_dev->write_pending = 1;
802 }
803
804 /**
805 * ifx_spi_free_port - free up the tty side
806 * @ifx_dev: IFX device going away
807 *
808 * Unregister and free up a port when the device goes away
809 */
ifx_spi_free_port(struct ifx_spi_device * ifx_dev)810 static void ifx_spi_free_port(struct ifx_spi_device *ifx_dev)
811 {
812 if (ifx_dev->tty_dev)
813 tty_unregister_device(tty_drv, ifx_dev->minor);
814 tty_port_destroy(&ifx_dev->tty_port);
815 kfifo_free(&ifx_dev->tx_fifo);
816 }
817
818 /**
819 * ifx_spi_create_port - create a new port
820 * @ifx_dev: our spi device
821 *
822 * Allocate and initialise the tty port that goes with this interface
823 * and add it to the tty layer so that it can be opened.
824 */
ifx_spi_create_port(struct ifx_spi_device * ifx_dev)825 static int ifx_spi_create_port(struct ifx_spi_device *ifx_dev)
826 {
827 int ret = 0;
828 struct tty_port *pport = &ifx_dev->tty_port;
829
830 spin_lock_init(&ifx_dev->fifo_lock);
831 lockdep_set_class_and_subclass(&ifx_dev->fifo_lock,
832 &ifx_spi_key, 0);
833
834 if (kfifo_alloc(&ifx_dev->tx_fifo, IFX_SPI_FIFO_SIZE, GFP_KERNEL)) {
835 ret = -ENOMEM;
836 goto error_ret;
837 }
838
839 tty_port_init(pport);
840 pport->ops = &ifx_tty_port_ops;
841 ifx_dev->minor = IFX_SPI_TTY_ID;
842 ifx_dev->tty_dev = tty_port_register_device(pport, tty_drv,
843 ifx_dev->minor, &ifx_dev->spi_dev->dev);
844 if (IS_ERR(ifx_dev->tty_dev)) {
845 dev_dbg(&ifx_dev->spi_dev->dev,
846 "%s: registering tty device failed", __func__);
847 ret = PTR_ERR(ifx_dev->tty_dev);
848 goto error_port;
849 }
850 return 0;
851
852 error_port:
853 tty_port_destroy(pport);
854 error_ret:
855 ifx_spi_free_port(ifx_dev);
856 return ret;
857 }
858
859 /**
860 * ifx_spi_handle_srdy - handle SRDY
861 * @ifx_dev: device asserting SRDY
862 *
863 * Check our device state and see what we need to kick off when SRDY
864 * is asserted. This usually means killing the timer and firing off the
865 * I/O processing.
866 */
ifx_spi_handle_srdy(struct ifx_spi_device * ifx_dev)867 static void ifx_spi_handle_srdy(struct ifx_spi_device *ifx_dev)
868 {
869 if (test_bit(IFX_SPI_STATE_TIMER_PENDING, &ifx_dev->flags)) {
870 del_timer(&ifx_dev->spi_timer);
871 clear_bit(IFX_SPI_STATE_TIMER_PENDING, &ifx_dev->flags);
872 }
873
874 ifx_spi_power_state_set(ifx_dev, IFX_SPI_POWER_SRDY);
875
876 if (!test_bit(IFX_SPI_STATE_IO_IN_PROGRESS, &ifx_dev->flags))
877 tasklet_schedule(&ifx_dev->io_work_tasklet);
878 else
879 set_bit(IFX_SPI_STATE_IO_READY, &ifx_dev->flags);
880 }
881
882 /**
883 * ifx_spi_srdy_interrupt - SRDY asserted
884 * @irq: our IRQ number
885 * @dev: our ifx device
886 *
887 * The modem asserted SRDY. Handle the srdy event
888 */
ifx_spi_srdy_interrupt(int irq,void * dev)889 static irqreturn_t ifx_spi_srdy_interrupt(int irq, void *dev)
890 {
891 struct ifx_spi_device *ifx_dev = dev;
892 ifx_dev->gpio.unack_srdy_int_nb++;
893 ifx_spi_handle_srdy(ifx_dev);
894 return IRQ_HANDLED;
895 }
896
897 /**
898 * ifx_spi_reset_interrupt - Modem has changed reset state
899 * @irq: interrupt number
900 * @dev: our device pointer
901 *
902 * The modem has either entered or left reset state. Check the GPIO
903 * line to see which.
904 *
905 * FIXME: review locking on MR_INPROGRESS versus
906 * parallel unsolicited reset/solicited reset
907 */
ifx_spi_reset_interrupt(int irq,void * dev)908 static irqreturn_t ifx_spi_reset_interrupt(int irq, void *dev)
909 {
910 struct ifx_spi_device *ifx_dev = dev;
911 int val = gpio_get_value(ifx_dev->gpio.reset_out);
912 int solreset = test_bit(MR_START, &ifx_dev->mdm_reset_state);
913
914 if (val == 0) {
915 /* entered reset */
916 set_bit(MR_INPROGRESS, &ifx_dev->mdm_reset_state);
917 if (!solreset) {
918 /* unsolicited reset */
919 tty_port_tty_hangup(&ifx_dev->tty_port, false);
920 }
921 } else {
922 /* exited reset */
923 clear_bit(MR_INPROGRESS, &ifx_dev->mdm_reset_state);
924 if (solreset) {
925 set_bit(MR_COMPLETE, &ifx_dev->mdm_reset_state);
926 wake_up(&ifx_dev->mdm_reset_wait);
927 }
928 }
929 return IRQ_HANDLED;
930 }
931
932 /**
933 * ifx_spi_free_device - free device
934 * @ifx_dev: device to free
935 *
936 * Free the IFX device
937 */
ifx_spi_free_device(struct ifx_spi_device * ifx_dev)938 static void ifx_spi_free_device(struct ifx_spi_device *ifx_dev)
939 {
940 ifx_spi_free_port(ifx_dev);
941 dma_free_coherent(&ifx_dev->spi_dev->dev,
942 IFX_SPI_TRANSFER_SIZE,
943 ifx_dev->tx_buffer,
944 ifx_dev->tx_bus);
945 dma_free_coherent(&ifx_dev->spi_dev->dev,
946 IFX_SPI_TRANSFER_SIZE,
947 ifx_dev->rx_buffer,
948 ifx_dev->rx_bus);
949 }
950
951 /**
952 * ifx_spi_reset - reset modem
953 * @ifx_dev: modem to reset
954 *
955 * Perform a reset on the modem
956 */
ifx_spi_reset(struct ifx_spi_device * ifx_dev)957 static int ifx_spi_reset(struct ifx_spi_device *ifx_dev)
958 {
959 int ret;
960 /*
961 * set up modem power, reset
962 *
963 * delays are required on some platforms for the modem
964 * to reset properly
965 */
966 set_bit(MR_START, &ifx_dev->mdm_reset_state);
967 gpio_set_value(ifx_dev->gpio.po, 0);
968 gpio_set_value(ifx_dev->gpio.reset, 0);
969 msleep(25);
970 gpio_set_value(ifx_dev->gpio.reset, 1);
971 msleep(1);
972 gpio_set_value(ifx_dev->gpio.po, 1);
973 msleep(1);
974 gpio_set_value(ifx_dev->gpio.po, 0);
975 ret = wait_event_timeout(ifx_dev->mdm_reset_wait,
976 test_bit(MR_COMPLETE,
977 &ifx_dev->mdm_reset_state),
978 IFX_RESET_TIMEOUT);
979 if (!ret)
980 dev_warn(&ifx_dev->spi_dev->dev, "Modem reset timeout: (state:%lx)",
981 ifx_dev->mdm_reset_state);
982
983 ifx_dev->mdm_reset_state = 0;
984 return ret;
985 }
986
987 /**
988 * ifx_spi_spi_probe - probe callback
989 * @spi: our possible matching SPI device
990 *
991 * Probe for a 6x60 modem on SPI bus. Perform any needed device and
992 * GPIO setup.
993 *
994 * FIXME:
995 * - Support for multiple devices
996 * - Split out MID specific GPIO handling eventually
997 */
998
ifx_spi_spi_probe(struct spi_device * spi)999 static int ifx_spi_spi_probe(struct spi_device *spi)
1000 {
1001 int ret;
1002 int srdy;
1003 struct ifx_modem_platform_data *pl_data;
1004 struct ifx_spi_device *ifx_dev;
1005
1006 if (saved_ifx_dev) {
1007 dev_dbg(&spi->dev, "ignoring subsequent detection");
1008 return -ENODEV;
1009 }
1010
1011 pl_data = dev_get_platdata(&spi->dev);
1012 if (!pl_data) {
1013 dev_err(&spi->dev, "missing platform data!");
1014 return -ENODEV;
1015 }
1016
1017 /* initialize structure to hold our device variables */
1018 ifx_dev = kzalloc(sizeof(struct ifx_spi_device), GFP_KERNEL);
1019 if (!ifx_dev) {
1020 dev_err(&spi->dev, "spi device allocation failed");
1021 return -ENOMEM;
1022 }
1023 saved_ifx_dev = ifx_dev;
1024 ifx_dev->spi_dev = spi;
1025 clear_bit(IFX_SPI_STATE_IO_IN_PROGRESS, &ifx_dev->flags);
1026 spin_lock_init(&ifx_dev->write_lock);
1027 spin_lock_init(&ifx_dev->power_lock);
1028 ifx_dev->power_status = 0;
1029 init_timer(&ifx_dev->spi_timer);
1030 ifx_dev->spi_timer.function = ifx_spi_timeout;
1031 ifx_dev->spi_timer.data = (unsigned long)ifx_dev;
1032 ifx_dev->modem = pl_data->modem_type;
1033 ifx_dev->use_dma = pl_data->use_dma;
1034 ifx_dev->max_hz = pl_data->max_hz;
1035 /* initialize spi mode, etc */
1036 spi->max_speed_hz = ifx_dev->max_hz;
1037 spi->mode = IFX_SPI_MODE | (SPI_LOOP & spi->mode);
1038 spi->bits_per_word = spi_bpw;
1039 ret = spi_setup(spi);
1040 if (ret) {
1041 dev_err(&spi->dev, "SPI setup wasn't successful %d", ret);
1042 return -ENODEV;
1043 }
1044
1045 /* init swap_buf function according to word width configuration */
1046 if (spi->bits_per_word == 32)
1047 ifx_dev->swap_buf = swap_buf_32;
1048 else if (spi->bits_per_word == 16)
1049 ifx_dev->swap_buf = swap_buf_16;
1050 else
1051 ifx_dev->swap_buf = swap_buf_8;
1052
1053 /* ensure SPI protocol flags are initialized to enable transfer */
1054 ifx_dev->spi_more = 0;
1055 ifx_dev->spi_slave_cts = 0;
1056
1057 /*initialize transfer and dma buffers */
1058 ifx_dev->tx_buffer = dma_alloc_coherent(ifx_dev->spi_dev->dev.parent,
1059 IFX_SPI_TRANSFER_SIZE,
1060 &ifx_dev->tx_bus,
1061 GFP_KERNEL);
1062 if (!ifx_dev->tx_buffer) {
1063 dev_err(&spi->dev, "DMA-TX buffer allocation failed");
1064 ret = -ENOMEM;
1065 goto error_ret;
1066 }
1067 ifx_dev->rx_buffer = dma_alloc_coherent(ifx_dev->spi_dev->dev.parent,
1068 IFX_SPI_TRANSFER_SIZE,
1069 &ifx_dev->rx_bus,
1070 GFP_KERNEL);
1071 if (!ifx_dev->rx_buffer) {
1072 dev_err(&spi->dev, "DMA-RX buffer allocation failed");
1073 ret = -ENOMEM;
1074 goto error_ret;
1075 }
1076
1077 /* initialize waitq for modem reset */
1078 init_waitqueue_head(&ifx_dev->mdm_reset_wait);
1079
1080 spi_set_drvdata(spi, ifx_dev);
1081 tasklet_init(&ifx_dev->io_work_tasklet, ifx_spi_io,
1082 (unsigned long)ifx_dev);
1083
1084 set_bit(IFX_SPI_STATE_PRESENT, &ifx_dev->flags);
1085
1086 /* create our tty port */
1087 ret = ifx_spi_create_port(ifx_dev);
1088 if (ret != 0) {
1089 dev_err(&spi->dev, "create default tty port failed");
1090 goto error_ret;
1091 }
1092
1093 ifx_dev->gpio.reset = pl_data->rst_pmu;
1094 ifx_dev->gpio.po = pl_data->pwr_on;
1095 ifx_dev->gpio.mrdy = pl_data->mrdy;
1096 ifx_dev->gpio.srdy = pl_data->srdy;
1097 ifx_dev->gpio.reset_out = pl_data->rst_out;
1098
1099 dev_info(&spi->dev, "gpios %d, %d, %d, %d, %d",
1100 ifx_dev->gpio.reset, ifx_dev->gpio.po, ifx_dev->gpio.mrdy,
1101 ifx_dev->gpio.srdy, ifx_dev->gpio.reset_out);
1102
1103 /* Configure gpios */
1104 ret = gpio_request(ifx_dev->gpio.reset, "ifxModem");
1105 if (ret < 0) {
1106 dev_err(&spi->dev, "Unable to allocate GPIO%d (RESET)",
1107 ifx_dev->gpio.reset);
1108 goto error_ret;
1109 }
1110 ret += gpio_direction_output(ifx_dev->gpio.reset, 0);
1111 ret += gpio_export(ifx_dev->gpio.reset, 1);
1112 if (ret) {
1113 dev_err(&spi->dev, "Unable to configure GPIO%d (RESET)",
1114 ifx_dev->gpio.reset);
1115 ret = -EBUSY;
1116 goto error_ret2;
1117 }
1118
1119 ret = gpio_request(ifx_dev->gpio.po, "ifxModem");
1120 ret += gpio_direction_output(ifx_dev->gpio.po, 0);
1121 ret += gpio_export(ifx_dev->gpio.po, 1);
1122 if (ret) {
1123 dev_err(&spi->dev, "Unable to configure GPIO%d (ON)",
1124 ifx_dev->gpio.po);
1125 ret = -EBUSY;
1126 goto error_ret3;
1127 }
1128
1129 ret = gpio_request(ifx_dev->gpio.mrdy, "ifxModem");
1130 if (ret < 0) {
1131 dev_err(&spi->dev, "Unable to allocate GPIO%d (MRDY)",
1132 ifx_dev->gpio.mrdy);
1133 goto error_ret3;
1134 }
1135 ret += gpio_export(ifx_dev->gpio.mrdy, 1);
1136 ret += gpio_direction_output(ifx_dev->gpio.mrdy, 0);
1137 if (ret) {
1138 dev_err(&spi->dev, "Unable to configure GPIO%d (MRDY)",
1139 ifx_dev->gpio.mrdy);
1140 ret = -EBUSY;
1141 goto error_ret4;
1142 }
1143
1144 ret = gpio_request(ifx_dev->gpio.srdy, "ifxModem");
1145 if (ret < 0) {
1146 dev_err(&spi->dev, "Unable to allocate GPIO%d (SRDY)",
1147 ifx_dev->gpio.srdy);
1148 ret = -EBUSY;
1149 goto error_ret4;
1150 }
1151 ret += gpio_export(ifx_dev->gpio.srdy, 1);
1152 ret += gpio_direction_input(ifx_dev->gpio.srdy);
1153 if (ret) {
1154 dev_err(&spi->dev, "Unable to configure GPIO%d (SRDY)",
1155 ifx_dev->gpio.srdy);
1156 ret = -EBUSY;
1157 goto error_ret5;
1158 }
1159
1160 ret = gpio_request(ifx_dev->gpio.reset_out, "ifxModem");
1161 if (ret < 0) {
1162 dev_err(&spi->dev, "Unable to allocate GPIO%d (RESET_OUT)",
1163 ifx_dev->gpio.reset_out);
1164 goto error_ret5;
1165 }
1166 ret += gpio_export(ifx_dev->gpio.reset_out, 1);
1167 ret += gpio_direction_input(ifx_dev->gpio.reset_out);
1168 if (ret) {
1169 dev_err(&spi->dev, "Unable to configure GPIO%d (RESET_OUT)",
1170 ifx_dev->gpio.reset_out);
1171 ret = -EBUSY;
1172 goto error_ret6;
1173 }
1174
1175 ret = request_irq(gpio_to_irq(ifx_dev->gpio.reset_out),
1176 ifx_spi_reset_interrupt,
1177 IRQF_TRIGGER_RISING|IRQF_TRIGGER_FALLING, DRVNAME,
1178 (void *)ifx_dev);
1179 if (ret) {
1180 dev_err(&spi->dev, "Unable to get irq %x\n",
1181 gpio_to_irq(ifx_dev->gpio.reset_out));
1182 goto error_ret6;
1183 }
1184
1185 ret = ifx_spi_reset(ifx_dev);
1186
1187 ret = request_irq(gpio_to_irq(ifx_dev->gpio.srdy),
1188 ifx_spi_srdy_interrupt,
1189 IRQF_TRIGGER_RISING, DRVNAME,
1190 (void *)ifx_dev);
1191 if (ret) {
1192 dev_err(&spi->dev, "Unable to get irq %x",
1193 gpio_to_irq(ifx_dev->gpio.srdy));
1194 goto error_ret7;
1195 }
1196
1197 /* set pm runtime power state and register with power system */
1198 pm_runtime_set_active(&spi->dev);
1199 pm_runtime_enable(&spi->dev);
1200
1201 /* handle case that modem is already signaling SRDY */
1202 /* no outgoing tty open at this point, this just satisfies the
1203 * modem's read and should reset communication properly
1204 */
1205 srdy = gpio_get_value(ifx_dev->gpio.srdy);
1206
1207 if (srdy) {
1208 mrdy_assert(ifx_dev);
1209 ifx_spi_handle_srdy(ifx_dev);
1210 } else
1211 mrdy_set_low(ifx_dev);
1212 return 0;
1213
1214 error_ret7:
1215 free_irq(gpio_to_irq(ifx_dev->gpio.reset_out), (void *)ifx_dev);
1216 error_ret6:
1217 gpio_free(ifx_dev->gpio.srdy);
1218 error_ret5:
1219 gpio_free(ifx_dev->gpio.mrdy);
1220 error_ret4:
1221 gpio_free(ifx_dev->gpio.reset);
1222 error_ret3:
1223 gpio_free(ifx_dev->gpio.po);
1224 error_ret2:
1225 gpio_free(ifx_dev->gpio.reset_out);
1226 error_ret:
1227 ifx_spi_free_device(ifx_dev);
1228 saved_ifx_dev = NULL;
1229 return ret;
1230 }
1231
1232 /**
1233 * ifx_spi_spi_remove - SPI device was removed
1234 * @spi: SPI device
1235 *
1236 * FIXME: We should be shutting the device down here not in
1237 * the module unload path.
1238 */
1239
ifx_spi_spi_remove(struct spi_device * spi)1240 static int ifx_spi_spi_remove(struct spi_device *spi)
1241 {
1242 struct ifx_spi_device *ifx_dev = spi_get_drvdata(spi);
1243 /* stop activity */
1244 tasklet_kill(&ifx_dev->io_work_tasklet);
1245 /* free irq */
1246 free_irq(gpio_to_irq(ifx_dev->gpio.reset_out), (void *)ifx_dev);
1247 free_irq(gpio_to_irq(ifx_dev->gpio.srdy), (void *)ifx_dev);
1248
1249 gpio_free(ifx_dev->gpio.srdy);
1250 gpio_free(ifx_dev->gpio.mrdy);
1251 gpio_free(ifx_dev->gpio.reset);
1252 gpio_free(ifx_dev->gpio.po);
1253 gpio_free(ifx_dev->gpio.reset_out);
1254
1255 /* free allocations */
1256 ifx_spi_free_device(ifx_dev);
1257
1258 saved_ifx_dev = NULL;
1259 return 0;
1260 }
1261
1262 /**
1263 * ifx_spi_spi_shutdown - called on SPI shutdown
1264 * @spi: SPI device
1265 *
1266 * No action needs to be taken here
1267 */
1268
ifx_spi_spi_shutdown(struct spi_device * spi)1269 static void ifx_spi_spi_shutdown(struct spi_device *spi)
1270 {
1271 struct ifx_spi_device *ifx_dev = spi_get_drvdata(spi);
1272
1273 ifx_modem_power_off(ifx_dev);
1274 }
1275
1276 /*
1277 * various suspends and resumes have nothing to do
1278 * no hardware to save state for
1279 */
1280
1281 /**
1282 * ifx_spi_pm_suspend - suspend modem on system suspend
1283 * @dev: device being suspended
1284 *
1285 * Suspend the modem. No action needed on Intel MID platforms, may
1286 * need extending for other systems.
1287 */
ifx_spi_pm_suspend(struct device * dev)1288 static int ifx_spi_pm_suspend(struct device *dev)
1289 {
1290 return 0;
1291 }
1292
1293 /**
1294 * ifx_spi_pm_resume - resume modem on system resume
1295 * @dev: device being suspended
1296 *
1297 * Allow the modem to resume. No action needed.
1298 *
1299 * FIXME: do we need to reset anything here ?
1300 */
ifx_spi_pm_resume(struct device * dev)1301 static int ifx_spi_pm_resume(struct device *dev)
1302 {
1303 return 0;
1304 }
1305
1306 /**
1307 * ifx_spi_pm_runtime_resume - suspend modem
1308 * @dev: device being suspended
1309 *
1310 * Allow the modem to resume. No action needed.
1311 */
ifx_spi_pm_runtime_resume(struct device * dev)1312 static int ifx_spi_pm_runtime_resume(struct device *dev)
1313 {
1314 return 0;
1315 }
1316
1317 /**
1318 * ifx_spi_pm_runtime_suspend - suspend modem
1319 * @dev: device being suspended
1320 *
1321 * Allow the modem to suspend and thus suspend to continue up the
1322 * device tree.
1323 */
ifx_spi_pm_runtime_suspend(struct device * dev)1324 static int ifx_spi_pm_runtime_suspend(struct device *dev)
1325 {
1326 return 0;
1327 }
1328
1329 /**
1330 * ifx_spi_pm_runtime_idle - check if modem idle
1331 * @dev: our device
1332 *
1333 * Check conditions and queue runtime suspend if idle.
1334 */
ifx_spi_pm_runtime_idle(struct device * dev)1335 static int ifx_spi_pm_runtime_idle(struct device *dev)
1336 {
1337 struct spi_device *spi = to_spi_device(dev);
1338 struct ifx_spi_device *ifx_dev = spi_get_drvdata(spi);
1339
1340 if (!ifx_dev->power_status)
1341 pm_runtime_suspend(dev);
1342
1343 return 0;
1344 }
1345
1346 static const struct dev_pm_ops ifx_spi_pm = {
1347 .resume = ifx_spi_pm_resume,
1348 .suspend = ifx_spi_pm_suspend,
1349 .runtime_resume = ifx_spi_pm_runtime_resume,
1350 .runtime_suspend = ifx_spi_pm_runtime_suspend,
1351 .runtime_idle = ifx_spi_pm_runtime_idle
1352 };
1353
1354 static const struct spi_device_id ifx_id_table[] = {
1355 {"ifx6160", 0},
1356 {"ifx6260", 0},
1357 { }
1358 };
1359 MODULE_DEVICE_TABLE(spi, ifx_id_table);
1360
1361 /* spi operations */
1362 static struct spi_driver ifx_spi_driver = {
1363 .driver = {
1364 .name = DRVNAME,
1365 .pm = &ifx_spi_pm,
1366 .owner = THIS_MODULE},
1367 .probe = ifx_spi_spi_probe,
1368 .shutdown = ifx_spi_spi_shutdown,
1369 .remove = ifx_spi_spi_remove,
1370 .id_table = ifx_id_table
1371 };
1372
1373 /**
1374 * ifx_spi_exit - module exit
1375 *
1376 * Unload the module.
1377 */
1378
ifx_spi_exit(void)1379 static void __exit ifx_spi_exit(void)
1380 {
1381 /* unregister */
1382 spi_unregister_driver((void *)&ifx_spi_driver);
1383 tty_unregister_driver(tty_drv);
1384 put_tty_driver(tty_drv);
1385 unregister_reboot_notifier(&ifx_modem_reboot_notifier_block);
1386 }
1387
1388 /**
1389 * ifx_spi_init - module entry point
1390 *
1391 * Initialise the SPI and tty interfaces for the IFX SPI driver
1392 * We need to initialize upper-edge spi driver after the tty
1393 * driver because otherwise the spi probe will race
1394 */
1395
ifx_spi_init(void)1396 static int __init ifx_spi_init(void)
1397 {
1398 int result;
1399
1400 tty_drv = alloc_tty_driver(1);
1401 if (!tty_drv) {
1402 pr_err("%s: alloc_tty_driver failed", DRVNAME);
1403 return -ENOMEM;
1404 }
1405
1406 tty_drv->driver_name = DRVNAME;
1407 tty_drv->name = TTYNAME;
1408 tty_drv->minor_start = IFX_SPI_TTY_ID;
1409 tty_drv->type = TTY_DRIVER_TYPE_SERIAL;
1410 tty_drv->subtype = SERIAL_TYPE_NORMAL;
1411 tty_drv->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
1412 tty_drv->init_termios = tty_std_termios;
1413
1414 tty_set_operations(tty_drv, &ifx_spi_serial_ops);
1415
1416 result = tty_register_driver(tty_drv);
1417 if (result) {
1418 pr_err("%s: tty_register_driver failed(%d)",
1419 DRVNAME, result);
1420 goto err_free_tty;
1421 }
1422
1423 result = spi_register_driver((void *)&ifx_spi_driver);
1424 if (result) {
1425 pr_err("%s: spi_register_driver failed(%d)",
1426 DRVNAME, result);
1427 goto err_unreg_tty;
1428 }
1429
1430 result = register_reboot_notifier(&ifx_modem_reboot_notifier_block);
1431 if (result) {
1432 pr_err("%s: register ifx modem reboot notifier failed(%d)",
1433 DRVNAME, result);
1434 goto err_unreg_spi;
1435 }
1436
1437 return 0;
1438 err_unreg_spi:
1439 spi_unregister_driver((void *)&ifx_spi_driver);
1440 err_unreg_tty:
1441 tty_unregister_driver(tty_drv);
1442 err_free_tty:
1443 put_tty_driver(tty_drv);
1444
1445 return result;
1446 }
1447
1448 module_init(ifx_spi_init);
1449 module_exit(ifx_spi_exit);
1450
1451 MODULE_AUTHOR("Intel");
1452 MODULE_DESCRIPTION("IFX6x60 spi driver");
1453 MODULE_LICENSE("GPL");
1454 MODULE_INFO(Version, "0.1-IFX6x60");
1455