?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
PM / sleep: Asynchronous threads for suspend_noirq
[linux/fpc-iii.git] / drivers / spi / spi-bfin-v3.c
blob8f8598834b30d0831ed08e6711a3528994f6df58
1 /*
2 * Analog Devices SPI3 controller driver
3 *
4 * Copyright (c) 2013 Analog Devices Inc.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 */
15
16 #include <linux/delay.h>
17 #include <linux/device.h>
18 #include <linux/dma-mapping.h>
19 #include <linux/errno.h>
20 #include <linux/gpio.h>
21 #include <linux/init.h>
22 #include <linux/interrupt.h>
23 #include <linux/io.h>
24 #include <linux/ioport.h>
25 #include <linux/module.h>
26 #include <linux/platform_device.h>
27 #include <linux/slab.h>
28 #include <linux/spi/spi.h>
29 #include <linux/types.h>
30
31 #include <asm/bfin_spi3.h>
32 #include <asm/cacheflush.h>
33 #include <asm/dma.h>
34 #include <asm/portmux.h>
35
36 enum bfin_spi_state {
37 START_STATE,
38 RUNNING_STATE,
39 DONE_STATE,
40 ERROR_STATE
41 };
42
43 struct bfin_spi_master;
44
45 struct bfin_spi_transfer_ops {
46 void (*write) (struct bfin_spi_master *);
47 void (*read) (struct bfin_spi_master *);
48 void (*duplex) (struct bfin_spi_master *);
49 };
50
51 /* runtime info for spi master */
52 struct bfin_spi_master {
53 /* SPI framework hookup */
54 struct spi_master *master;
55
56 /* Regs base of SPI controller */
57 struct bfin_spi_regs __iomem *regs;
58
59 /* Pin request list */
60 u16 *pin_req;
61
62 /* Message Transfer pump */
63 struct tasklet_struct pump_transfers;
64
65 /* Current message transfer state info */
66 struct spi_message *cur_msg;
67 struct spi_transfer *cur_transfer;
68 struct bfin_spi_device *cur_chip;
69 unsigned transfer_len;
70
71 /* transfer buffer */
72 void *tx;
73 void *tx_end;
74 void *rx;
75 void *rx_end;
76
77 /* dma info */
78 unsigned int tx_dma;
79 unsigned int rx_dma;
80 dma_addr_t tx_dma_addr;
81 dma_addr_t rx_dma_addr;
82 unsigned long dummy_buffer; /* used in unidirectional transfer */
83 unsigned long tx_dma_size;
84 unsigned long rx_dma_size;
85 int tx_num;
86 int rx_num;
87
88 /* store register value for suspend/resume */
89 u32 control;
90 u32 ssel;
91
92 unsigned long sclk;
93 enum bfin_spi_state state;
94
95 const struct bfin_spi_transfer_ops *ops;
96 };
97
98 struct bfin_spi_device {
99 u32 control;
100 u32 clock;
101 u32 ssel;
102
103 u8 cs;
104 u16 cs_chg_udelay; /* Some devices require > 255usec delay */
105 u32 cs_gpio;
106 u32 tx_dummy_val; /* tx value for rx only transfer */
107 bool enable_dma;
108 const struct bfin_spi_transfer_ops *ops;
109 };
110
111 static void bfin_spi_enable(struct bfin_spi_master *drv_data)
112 {
113 bfin_write_or(&drv_data->regs->control, SPI_CTL_EN);
114 }
115
116 static void bfin_spi_disable(struct bfin_spi_master *drv_data)
117 {
118 bfin_write_and(&drv_data->regs->control, ~SPI_CTL_EN);
119 }
120
121 /* Caculate the SPI_CLOCK register value based on input HZ */
122 static u32 hz_to_spi_clock(u32 sclk, u32 speed_hz)
123 {
124 u32 spi_clock = sclk / speed_hz;
125
126 if (spi_clock)
127 spi_clock--;
128 return spi_clock;
129 }
130
131 static int bfin_spi_flush(struct bfin_spi_master *drv_data)
132 {
133 unsigned long limit = loops_per_jiffy << 1;
134
135 /* wait for stop and clear stat */
136 while (!(bfin_read(&drv_data->regs->status) & SPI_STAT_SPIF) && --limit)
137 cpu_relax();
138
139 bfin_write(&drv_data->regs->status, 0xFFFFFFFF);
140
141 return limit;
142 }
143
144 /* Chip select operation functions for cs_change flag */
145 static void bfin_spi_cs_active(struct bfin_spi_master *drv_data, struct bfin_spi_device *chip)
146 {
147 if (likely(chip->cs < MAX_CTRL_CS))
148 bfin_write_and(&drv_data->regs->ssel, ~chip->ssel);
149 else
150 gpio_set_value(chip->cs_gpio, 0);
151 }
152
153 static void bfin_spi_cs_deactive(struct bfin_spi_master *drv_data,
154 struct bfin_spi_device *chip)
155 {
156 if (likely(chip->cs < MAX_CTRL_CS))
157 bfin_write_or(&drv_data->regs->ssel, chip->ssel);
158 else
159 gpio_set_value(chip->cs_gpio, 1);
160
161 /* Move delay here for consistency */
162 if (chip->cs_chg_udelay)
163 udelay(chip->cs_chg_udelay);
164 }
165
166 /* enable or disable the pin muxed by GPIO and SPI CS to work as SPI CS */
167 static inline void bfin_spi_cs_enable(struct bfin_spi_master *drv_data,
168 struct bfin_spi_device *chip)
169 {
170 if (chip->cs < MAX_CTRL_CS)
171 bfin_write_or(&drv_data->regs->ssel, chip->ssel >> 8);
172 }
173
174 static inline void bfin_spi_cs_disable(struct bfin_spi_master *drv_data,
175 struct bfin_spi_device *chip)
176 {
177 if (chip->cs < MAX_CTRL_CS)
178 bfin_write_and(&drv_data->regs->ssel, ~(chip->ssel >> 8));
179 }
180
181 /* stop controller and re-config current chip*/
182 static void bfin_spi_restore_state(struct bfin_spi_master *drv_data)
183 {
184 struct bfin_spi_device *chip = drv_data->cur_chip;
185
186 /* Clear status and disable clock */
187 bfin_write(&drv_data->regs->status, 0xFFFFFFFF);
188 bfin_write(&drv_data->regs->rx_control, 0x0);
189 bfin_write(&drv_data->regs->tx_control, 0x0);
190 bfin_spi_disable(drv_data);
191
192 SSYNC();
193
194 /* Load the registers */
195 bfin_write(&drv_data->regs->control, chip->control);
196 bfin_write(&drv_data->regs->clock, chip->clock);
197
198 bfin_spi_enable(drv_data);
199 drv_data->tx_num = drv_data->rx_num = 0;
200 /* we always choose tx transfer initiate */
201 bfin_write(&drv_data->regs->rx_control, SPI_RXCTL_REN);
202 bfin_write(&drv_data->regs->tx_control,
203 SPI_TXCTL_TEN | SPI_TXCTL_TTI);
204 bfin_spi_cs_active(drv_data, chip);
205 }
206
207 /* discard invalid rx data and empty rfifo */
208 static inline void dummy_read(struct bfin_spi_master *drv_data)
209 {
210 while (!(bfin_read(&drv_data->regs->status) & SPI_STAT_RFE))
211 bfin_read(&drv_data->regs->rfifo);
212 }
213
214 static void bfin_spi_u8_write(struct bfin_spi_master *drv_data)
215 {
216 dummy_read(drv_data);
217 while (drv_data->tx < drv_data->tx_end) {
218 bfin_write(&drv_data->regs->tfifo, (*(u8 *)(drv_data->tx++)));
219 while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
220 cpu_relax();
221 bfin_read(&drv_data->regs->rfifo);
222 }
223 }
224
225 static void bfin_spi_u8_read(struct bfin_spi_master *drv_data)
226 {
227 u32 tx_val = drv_data->cur_chip->tx_dummy_val;
228
229 dummy_read(drv_data);
230 while (drv_data->rx < drv_data->rx_end) {
231 bfin_write(&drv_data->regs->tfifo, tx_val);
232 while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
233 cpu_relax();
234 *(u8 *)(drv_data->rx++) = bfin_read(&drv_data->regs->rfifo);
235 }
236 }
237
238 static void bfin_spi_u8_duplex(struct bfin_spi_master *drv_data)
239 {
240 dummy_read(drv_data);
241 while (drv_data->rx < drv_data->rx_end) {
242 bfin_write(&drv_data->regs->tfifo, (*(u8 *)(drv_data->tx++)));
243 while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
244 cpu_relax();
245 *(u8 *)(drv_data->rx++) = bfin_read(&drv_data->regs->rfifo);
246 }
247 }
248
249 static const struct bfin_spi_transfer_ops bfin_bfin_spi_transfer_ops_u8 = {
250 .write = bfin_spi_u8_write,
251 .read = bfin_spi_u8_read,
252 .duplex = bfin_spi_u8_duplex,
253 };
254
255 static void bfin_spi_u16_write(struct bfin_spi_master *drv_data)
256 {
257 dummy_read(drv_data);
258 while (drv_data->tx < drv_data->tx_end) {
259 bfin_write(&drv_data->regs->tfifo, (*(u16 *)drv_data->tx));
260 drv_data->tx += 2;
261 while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
262 cpu_relax();
263 bfin_read(&drv_data->regs->rfifo);
264 }
265 }
266
267 static void bfin_spi_u16_read(struct bfin_spi_master *drv_data)
268 {
269 u32 tx_val = drv_data->cur_chip->tx_dummy_val;
270
271 dummy_read(drv_data);
272 while (drv_data->rx < drv_data->rx_end) {
273 bfin_write(&drv_data->regs->tfifo, tx_val);
274 while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
275 cpu_relax();
276 *(u16 *)drv_data->rx = bfin_read(&drv_data->regs->rfifo);
277 drv_data->rx += 2;
278 }
279 }
280
281 static void bfin_spi_u16_duplex(struct bfin_spi_master *drv_data)
282 {
283 dummy_read(drv_data);
284 while (drv_data->rx < drv_data->rx_end) {
285 bfin_write(&drv_data->regs->tfifo, (*(u16 *)drv_data->tx));
286 drv_data->tx += 2;
287 while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
288 cpu_relax();
289 *(u16 *)drv_data->rx = bfin_read(&drv_data->regs->rfifo);
290 drv_data->rx += 2;
291 }
292 }
293
294 static const struct bfin_spi_transfer_ops bfin_bfin_spi_transfer_ops_u16 = {
295 .write = bfin_spi_u16_write,
296 .read = bfin_spi_u16_read,
297 .duplex = bfin_spi_u16_duplex,
298 };
299
300 static void bfin_spi_u32_write(struct bfin_spi_master *drv_data)
301 {
302 dummy_read(drv_data);
303 while (drv_data->tx < drv_data->tx_end) {
304 bfin_write(&drv_data->regs->tfifo, (*(u32 *)drv_data->tx));
305 drv_data->tx += 4;
306 while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
307 cpu_relax();
308 bfin_read(&drv_data->regs->rfifo);
309 }
310 }
311
312 static void bfin_spi_u32_read(struct bfin_spi_master *drv_data)
313 {
314 u32 tx_val = drv_data->cur_chip->tx_dummy_val;
315
316 dummy_read(drv_data);
317 while (drv_data->rx < drv_data->rx_end) {
318 bfin_write(&drv_data->regs->tfifo, tx_val);
319 while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
320 cpu_relax();
321 *(u32 *)drv_data->rx = bfin_read(&drv_data->regs->rfifo);
322 drv_data->rx += 4;
323 }
324 }
325
326 static void bfin_spi_u32_duplex(struct bfin_spi_master *drv_data)
327 {
328 dummy_read(drv_data);
329 while (drv_data->rx < drv_data->rx_end) {
330 bfin_write(&drv_data->regs->tfifo, (*(u32 *)drv_data->tx));
331 drv_data->tx += 4;
332 while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
333 cpu_relax();
334 *(u32 *)drv_data->rx = bfin_read(&drv_data->regs->rfifo);
335 drv_data->rx += 4;
336 }
337 }
338
339 static const struct bfin_spi_transfer_ops bfin_bfin_spi_transfer_ops_u32 = {
340 .write = bfin_spi_u32_write,
341 .read = bfin_spi_u32_read,
342 .duplex = bfin_spi_u32_duplex,
343 };
344
345
346 /* test if there is more transfer to be done */
347 static void bfin_spi_next_transfer(struct bfin_spi_master *drv)
348 {
349 struct spi_message *msg = drv->cur_msg;
350 struct spi_transfer *t = drv->cur_transfer;
351
352 /* Move to next transfer */
353 if (t->transfer_list.next != &msg->transfers) {
354 drv->cur_transfer = list_entry(t->transfer_list.next,
355 struct spi_transfer, transfer_list);
356 drv->state = RUNNING_STATE;
357 } else {
358 drv->state = DONE_STATE;
359 drv->cur_transfer = NULL;
360 }
361 }
362
363 static void bfin_spi_giveback(struct bfin_spi_master *drv_data)
364 {
365 struct bfin_spi_device *chip = drv_data->cur_chip;
366
367 bfin_spi_cs_deactive(drv_data, chip);
368 spi_finalize_current_message(drv_data->master);
369 }
370
371 static int bfin_spi_setup_transfer(struct bfin_spi_master *drv)
372 {
373 struct spi_transfer *t = drv->cur_transfer;
374 u32 cr, cr_width;
375
376 if (t->tx_buf) {
377 drv->tx = (void *)t->tx_buf;
378 drv->tx_end = drv->tx + t->len;
379 } else {
380 drv->tx = NULL;
381 }
382
383 if (t->rx_buf) {
384 drv->rx = t->rx_buf;
385 drv->rx_end = drv->rx + t->len;
386 } else {
387 drv->rx = NULL;
388 }
389
390 drv->transfer_len = t->len;
391
392 /* bits per word setup */
393 switch (t->bits_per_word) {
394 case 8:
395 cr_width = SPI_CTL_SIZE08;
396 drv->ops = &bfin_bfin_spi_transfer_ops_u8;
397 break;
398 case 16:
399 cr_width = SPI_CTL_SIZE16;
400 drv->ops = &bfin_bfin_spi_transfer_ops_u16;
401 break;
402 case 32:
403 cr_width = SPI_CTL_SIZE32;
404 drv->ops = &bfin_bfin_spi_transfer_ops_u32;
405 break;
406 default:
407 return -EINVAL;
408 }
409 cr = bfin_read(&drv->regs->control) & ~SPI_CTL_SIZE;
410 cr |= cr_width;
411 bfin_write(&drv->regs->control, cr);
412
413 /* speed setup */
414 bfin_write(&drv->regs->clock,
415 hz_to_spi_clock(drv->sclk, t->speed_hz));
416 return 0;
417 }
418
419 static int bfin_spi_dma_xfer(struct bfin_spi_master *drv_data)
420 {
421 struct spi_transfer *t = drv_data->cur_transfer;
422 struct spi_message *msg = drv_data->cur_msg;
423 struct bfin_spi_device *chip = drv_data->cur_chip;
424 u32 dma_config;
425 unsigned long word_count, word_size;
426 void *tx_buf, *rx_buf;
427
428 switch (t->bits_per_word) {
429 case 8:
430 dma_config = WDSIZE_8 | PSIZE_8;
431 word_count = drv_data->transfer_len;
432 word_size = 1;
433 break;
434 case 16:
435 dma_config = WDSIZE_16 | PSIZE_16;
436 word_count = drv_data->transfer_len / 2;
437 word_size = 2;
438 break;
439 default:
440 dma_config = WDSIZE_32 | PSIZE_32;
441 word_count = drv_data->transfer_len / 4;
442 word_size = 4;
443 break;
444 }
445
446 if (!drv_data->rx) {
447 tx_buf = drv_data->tx;
448 rx_buf = &drv_data->dummy_buffer;
449 drv_data->tx_dma_size = drv_data->transfer_len;
450 drv_data->rx_dma_size = sizeof(drv_data->dummy_buffer);
451 set_dma_x_modify(drv_data->tx_dma, word_size);
452 set_dma_x_modify(drv_data->rx_dma, 0);
453 } else if (!drv_data->tx) {
454 drv_data->dummy_buffer = chip->tx_dummy_val;
455 tx_buf = &drv_data->dummy_buffer;
456 rx_buf = drv_data->rx;
457 drv_data->tx_dma_size = sizeof(drv_data->dummy_buffer);
458 drv_data->rx_dma_size = drv_data->transfer_len;
459 set_dma_x_modify(drv_data->tx_dma, 0);
460 set_dma_x_modify(drv_data->rx_dma, word_size);
461 } else {
462 tx_buf = drv_data->tx;
463 rx_buf = drv_data->rx;
464 drv_data->tx_dma_size = drv_data->rx_dma_size
465 = drv_data->transfer_len;
466 set_dma_x_modify(drv_data->tx_dma, word_size);
467 set_dma_x_modify(drv_data->rx_dma, word_size);
468 }
469
470 drv_data->tx_dma_addr = dma_map_single(&msg->spi->dev,
471 (void *)tx_buf,
472 drv_data->tx_dma_size,
473 DMA_TO_DEVICE);
474 if (dma_mapping_error(&msg->spi->dev,
475 drv_data->tx_dma_addr))
476 return -ENOMEM;
477
478 drv_data->rx_dma_addr = dma_map_single(&msg->spi->dev,
479 (void *)rx_buf,
480 drv_data->rx_dma_size,
481 DMA_FROM_DEVICE);
482 if (dma_mapping_error(&msg->spi->dev,
483 drv_data->rx_dma_addr)) {
484 dma_unmap_single(&msg->spi->dev,
485 drv_data->tx_dma_addr,
486 drv_data->tx_dma_size,
487 DMA_TO_DEVICE);
488 return -ENOMEM;
489 }
490
491 dummy_read(drv_data);
492 set_dma_x_count(drv_data->tx_dma, word_count);
493 set_dma_x_count(drv_data->rx_dma, word_count);
494 set_dma_start_addr(drv_data->tx_dma, drv_data->tx_dma_addr);
495 set_dma_start_addr(drv_data->rx_dma, drv_data->rx_dma_addr);
496 dma_config |= DMAFLOW_STOP | RESTART | DI_EN;
497 set_dma_config(drv_data->tx_dma, dma_config);
498 set_dma_config(drv_data->rx_dma, dma_config | WNR);
499 enable_dma(drv_data->tx_dma);
500 enable_dma(drv_data->rx_dma);
501 SSYNC();
502
503 bfin_write(&drv_data->regs->rx_control, SPI_RXCTL_REN | SPI_RXCTL_RDR_NE);
504 SSYNC();
505 bfin_write(&drv_data->regs->tx_control,
506 SPI_TXCTL_TEN | SPI_TXCTL_TTI | SPI_TXCTL_TDR_NF);
507
508 return 0;
509 }
510
511 static int bfin_spi_pio_xfer(struct bfin_spi_master *drv_data)
512 {
513 struct spi_message *msg = drv_data->cur_msg;
514
515 if (!drv_data->rx) {
516 /* write only half duplex */
517 drv_data->ops->write(drv_data);
518 if (drv_data->tx != drv_data->tx_end)
519 return -EIO;
520 } else if (!drv_data->tx) {
521 /* read only half duplex */
522 drv_data->ops->read(drv_data);
523 if (drv_data->rx != drv_data->rx_end)
524 return -EIO;
525 } else {
526 /* full duplex mode */
527 drv_data->ops->duplex(drv_data);
528 if (drv_data->tx != drv_data->tx_end)
529 return -EIO;
530 }
531
532 if (!bfin_spi_flush(drv_data))
533 return -EIO;
534 msg->actual_length += drv_data->transfer_len;
535 tasklet_schedule(&drv_data->pump_transfers);
536 return 0;
537 }
538
539 static void bfin_spi_pump_transfers(unsigned long data)
540 {
541 struct bfin_spi_master *drv_data = (struct bfin_spi_master *)data;
542 struct spi_message *msg = NULL;
543 struct spi_transfer *t = NULL;
544 struct bfin_spi_device *chip = NULL;
545 int ret;
546
547 /* Get current state information */
548 msg = drv_data->cur_msg;
549 t = drv_data->cur_transfer;
550 chip = drv_data->cur_chip;
551
552 /* Handle for abort */
553 if (drv_data->state == ERROR_STATE) {
554 msg->status = -EIO;
555 bfin_spi_giveback(drv_data);
556 return;
557 }
558
559 if (drv_data->state == RUNNING_STATE) {
560 if (t->delay_usecs)
561 udelay(t->delay_usecs);
562 if (t->cs_change)
563 bfin_spi_cs_deactive(drv_data, chip);
564 bfin_spi_next_transfer(drv_data);
565 t = drv_data->cur_transfer;
566 }
567 /* Handle end of message */
568 if (drv_data->state == DONE_STATE) {
569 msg->status = 0;
570 bfin_spi_giveback(drv_data);
571 return;
572 }
573
574 if ((t->len == 0) || (t->tx_buf == NULL && t->rx_buf == NULL)) {
575 /* Schedule next transfer tasklet */
576 tasklet_schedule(&drv_data->pump_transfers);
577 return;
578 }
579
580 ret = bfin_spi_setup_transfer(drv_data);
581 if (ret) {
582 msg->status = ret;
583 bfin_spi_giveback(drv_data);
584 }
585
586 bfin_write(&drv_data->regs->status, 0xFFFFFFFF);
587 bfin_spi_cs_active(drv_data, chip);
588 drv_data->state = RUNNING_STATE;
589
590 if (chip->enable_dma)
591 ret = bfin_spi_dma_xfer(drv_data);
592 else
593 ret = bfin_spi_pio_xfer(drv_data);
594 if (ret) {
595 msg->status = ret;
596 bfin_spi_giveback(drv_data);
597 }
598 }
599
600 static int bfin_spi_transfer_one_message(struct spi_master *master,
601 struct spi_message *m)
602 {
603 struct bfin_spi_master *drv_data = spi_master_get_devdata(master);
604
605 drv_data->cur_msg = m;
606 drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi);
607 bfin_spi_restore_state(drv_data);
608
609 drv_data->state = START_STATE;
610 drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next,
611 struct spi_transfer, transfer_list);
612
613 tasklet_schedule(&drv_data->pump_transfers);
614 return 0;
615 }
616
617 #define MAX_SPI_SSEL 7
618
619 static const u16 ssel[][MAX_SPI_SSEL] = {
620 {P_SPI0_SSEL1, P_SPI0_SSEL2, P_SPI0_SSEL3,
621 P_SPI0_SSEL4, P_SPI0_SSEL5,
622 P_SPI0_SSEL6, P_SPI0_SSEL7},
623
624 {P_SPI1_SSEL1, P_SPI1_SSEL2, P_SPI1_SSEL3,
625 P_SPI1_SSEL4, P_SPI1_SSEL5,
626 P_SPI1_SSEL6, P_SPI1_SSEL7},
627
628 {P_SPI2_SSEL1, P_SPI2_SSEL2, P_SPI2_SSEL3,
629 P_SPI2_SSEL4, P_SPI2_SSEL5,
630 P_SPI2_SSEL6, P_SPI2_SSEL7},
631 };
632
633 static int bfin_spi_setup(struct spi_device *spi)
634 {
635 struct bfin_spi_master *drv_data = spi_master_get_devdata(spi->master);
636 struct bfin_spi_device *chip = spi_get_ctldata(spi);
637 u32 bfin_ctl_reg = SPI_CTL_ODM | SPI_CTL_PSSE;
638 int ret = -EINVAL;
639
640 if (!chip) {
641 struct bfin_spi3_chip *chip_info = spi->controller_data;
642
643 chip = kzalloc(sizeof(*chip), GFP_KERNEL);
644 if (!chip) {
645 dev_err(&spi->dev, "can not allocate chip data\n");
646 return -ENOMEM;
647 }
648 if (chip_info) {
649 if (chip_info->control & ~bfin_ctl_reg) {
650 dev_err(&spi->dev,
651 "do not set bits that the SPI framework manages\n");
652 goto error;
653 }
654 chip->control = chip_info->control;
655 chip->cs_chg_udelay = chip_info->cs_chg_udelay;
656 chip->tx_dummy_val = chip_info->tx_dummy_val;
657 chip->enable_dma = chip_info->enable_dma;
658 }
659 chip->cs = spi->chip_select;
660 if (chip->cs < MAX_CTRL_CS) {
661 chip->ssel = (1 << chip->cs) << 8;
662 ret = peripheral_request(ssel[spi->master->bus_num]
663 [chip->cs-1], dev_name(&spi->dev));
664 if (ret) {
665 dev_err(&spi->dev, "peripheral_request() error\n");
666 goto error;
667 }
668 } else {
669 chip->cs_gpio = chip->cs - MAX_CTRL_CS;
670 ret = gpio_request_one(chip->cs_gpio, GPIOF_OUT_INIT_HIGH,
671 dev_name(&spi->dev));
672 if (ret) {
673 dev_err(&spi->dev, "gpio_request_one() error\n");
674 goto error;
675 }
676 }
677 spi_set_ctldata(spi, chip);
678 }
679
680 /* force a default base state */
681 chip->control &= bfin_ctl_reg;
682
683 if (spi->mode & SPI_CPOL)
684 chip->control |= SPI_CTL_CPOL;
685 if (spi->mode & SPI_CPHA)
686 chip->control |= SPI_CTL_CPHA;
687 if (spi->mode & SPI_LSB_FIRST)
688 chip->control |= SPI_CTL_LSBF;
689 chip->control |= SPI_CTL_MSTR;
690 /* we choose software to controll cs */
691 chip->control &= ~SPI_CTL_ASSEL;
692
693 chip->clock = hz_to_spi_clock(drv_data->sclk, spi->max_speed_hz);
694
695 bfin_spi_cs_enable(drv_data, chip);
696 bfin_spi_cs_deactive(drv_data, chip);
697
698 return 0;
699 error:
700 if (chip) {
701 kfree(chip);
702 spi_set_ctldata(spi, NULL);
703 }
704
705 return ret;
706 }
707
708 static void bfin_spi_cleanup(struct spi_device *spi)
709 {
710 struct bfin_spi_device *chip = spi_get_ctldata(spi);
711 struct bfin_spi_master *drv_data = spi_master_get_devdata(spi->master);
712
713 if (!chip)
714 return;
715
716 if (chip->cs < MAX_CTRL_CS) {
717 peripheral_free(ssel[spi->master->bus_num]
718 [chip->cs-1]);
719 bfin_spi_cs_disable(drv_data, chip);
720 } else {
721 gpio_free(chip->cs_gpio);
722 }
723
724 kfree(chip);
725 spi_set_ctldata(spi, NULL);
726 }
727
728 static irqreturn_t bfin_spi_tx_dma_isr(int irq, void *dev_id)
729 {
730 struct bfin_spi_master *drv_data = dev_id;
731 u32 dma_stat = get_dma_curr_irqstat(drv_data->tx_dma);
732
733 clear_dma_irqstat(drv_data->tx_dma);
734 if (dma_stat & DMA_DONE) {
735 drv_data->tx_num++;
736 } else {
737 dev_err(&drv_data->master->dev,
738 "spi tx dma error: %d\n", dma_stat);
739 if (drv_data->tx)
740 drv_data->state = ERROR_STATE;
741 }
742 bfin_write_and(&drv_data->regs->tx_control, ~SPI_TXCTL_TDR_NF);
743 return IRQ_HANDLED;
744 }
745
746 static irqreturn_t bfin_spi_rx_dma_isr(int irq, void *dev_id)
747 {
748 struct bfin_spi_master *drv_data = dev_id;
749 struct spi_message *msg = drv_data->cur_msg;
750 u32 dma_stat = get_dma_curr_irqstat(drv_data->rx_dma);
751
752 clear_dma_irqstat(drv_data->rx_dma);
753 if (dma_stat & DMA_DONE) {
754 drv_data->rx_num++;
755 /* we may fail on tx dma */
756 if (drv_data->state != ERROR_STATE)
757 msg->actual_length += drv_data->transfer_len;
758 } else {
759 drv_data->state = ERROR_STATE;
760 dev_err(&drv_data->master->dev,
761 "spi rx dma error: %d\n", dma_stat);
762 }
763 bfin_write(&drv_data->regs->tx_control, 0);
764 bfin_write(&drv_data->regs->rx_control, 0);
765 if (drv_data->rx_num != drv_data->tx_num)
766 dev_dbg(&drv_data->master->dev,
767 "dma interrupt missing: tx=%d,rx=%d\n",
768 drv_data->tx_num, drv_data->rx_num);
769 tasklet_schedule(&drv_data->pump_transfers);
770 return IRQ_HANDLED;
771 }
772
773 static int bfin_spi_probe(struct platform_device *pdev)
774 {
775 struct device *dev = &pdev->dev;
776 struct bfin_spi3_master *info = dev_get_platdata(dev);
777 struct spi_master *master;
778 struct bfin_spi_master *drv_data;
779 struct resource *mem, *res;
780 unsigned int tx_dma, rx_dma;
781 unsigned long sclk;
782 int ret;
783
784 if (!info) {
785 dev_err(dev, "platform data missing!\n");
786 return -ENODEV;
787 }
788
789 sclk = get_sclk1();
790 if (!sclk) {
791 dev_err(dev, "can not get sclk1\n");
792 return -ENXIO;
793 }
794
795 res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
796 if (!res) {
797 dev_err(dev, "can not get tx dma resource\n");
798 return -ENXIO;
799 }
800 tx_dma = res->start;
801
802 res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
803 if (!res) {
804 dev_err(dev, "can not get rx dma resource\n");
805 return -ENXIO;
806 }
807 rx_dma = res->start;
808
809 /* allocate master with space for drv_data */
810 master = spi_alloc_master(dev, sizeof(*drv_data));
811 if (!master) {
812 dev_err(dev, "can not alloc spi_master\n");
813 return -ENOMEM;
814 }
815 platform_set_drvdata(pdev, master);
816
817 /* the mode bits supported by this driver */
818 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
819
820 master->bus_num = pdev->id;
821 master->num_chipselect = info->num_chipselect;
822 master->cleanup = bfin_spi_cleanup;
823 master->setup = bfin_spi_setup;
824 master->transfer_one_message = bfin_spi_transfer_one_message;
825 master->bits_per_word_mask = BIT(32 - 1) | BIT(16 - 1) | BIT(8 - 1);
826
827 drv_data = spi_master_get_devdata(master);
828 drv_data->master = master;
829 drv_data->tx_dma = tx_dma;
830 drv_data->rx_dma = rx_dma;
831 drv_data->pin_req = info->pin_req;
832 drv_data->sclk = sclk;
833
834 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
835 drv_data->regs = devm_ioremap_resource(dev, mem);
836 if (IS_ERR(drv_data->regs)) {
837 ret = PTR_ERR(drv_data->regs);
838 goto err_put_master;
839 }
840
841 /* request tx and rx dma */
842 ret = request_dma(tx_dma, "SPI_TX_DMA");
843 if (ret) {
844 dev_err(dev, "can not request SPI TX DMA channel\n");
845 goto err_put_master;
846 }
847 set_dma_callback(tx_dma, bfin_spi_tx_dma_isr, drv_data);
848
849 ret = request_dma(rx_dma, "SPI_RX_DMA");
850 if (ret) {
851 dev_err(dev, "can not request SPI RX DMA channel\n");
852 goto err_free_tx_dma;
853 }
854 set_dma_callback(drv_data->rx_dma, bfin_spi_rx_dma_isr, drv_data);
855
856 /* request CLK, MOSI and MISO */
857 ret = peripheral_request_list(drv_data->pin_req, "bfin-spi3");
858 if (ret < 0) {
859 dev_err(dev, "can not request spi pins\n");
860 goto err_free_rx_dma;
861 }
862
863 bfin_write(&drv_data->regs->control, SPI_CTL_MSTR | SPI_CTL_CPHA);
864 bfin_write(&drv_data->regs->ssel, 0x0000FE00);
865 bfin_write(&drv_data->regs->delay, 0x0);
866
867 tasklet_init(&drv_data->pump_transfers,
868 bfin_spi_pump_transfers, (unsigned long)drv_data);
869 /* register with the SPI framework */
870 ret = devm_spi_register_master(dev, master);
871 if (ret) {
872 dev_err(dev, "can not register spi master\n");
873 goto err_free_peripheral;
874 }
875
876 return ret;
877
878 err_free_peripheral:
879 peripheral_free_list(drv_data->pin_req);
880 err_free_rx_dma:
881 free_dma(rx_dma);
882 err_free_tx_dma:
883 free_dma(tx_dma);
884 err_put_master:
885 spi_master_put(master);
886
887 return ret;
888 }
889
890 static int bfin_spi_remove(struct platform_device *pdev)
891 {
892 struct spi_master *master = platform_get_drvdata(pdev);
893 struct bfin_spi_master *drv_data = spi_master_get_devdata(master);
894
895 bfin_spi_disable(drv_data);
896
897 peripheral_free_list(drv_data->pin_req);
898 free_dma(drv_data->rx_dma);
899 free_dma(drv_data->tx_dma);
900
901 return 0;
902 }
903
904 #ifdef CONFIG_PM
905 static int bfin_spi_suspend(struct device *dev)
906 {
907 struct spi_master *master = dev_get_drvdata(dev);
908 struct bfin_spi_master *drv_data = spi_master_get_devdata(master);
909
910 spi_master_suspend(master);
911
912 drv_data->control = bfin_read(&drv_data->regs->control);
913 drv_data->ssel = bfin_read(&drv_data->regs->ssel);
914
915 bfin_write(&drv_data->regs->control, SPI_CTL_MSTR | SPI_CTL_CPHA);
916 bfin_write(&drv_data->regs->ssel, 0x0000FE00);
917 dma_disable_irq(drv_data->rx_dma);
918 dma_disable_irq(drv_data->tx_dma);
919
920 return 0;
921 }
922
923 static int bfin_spi_resume(struct device *dev)
924 {
925 struct spi_master *master = dev_get_drvdata(dev);
926 struct bfin_spi_master *drv_data = spi_master_get_devdata(master);
927 int ret = 0;
928
929 /* bootrom may modify spi and dma status when resume in spi boot mode */
930 disable_dma(drv_data->rx_dma);
931
932 dma_enable_irq(drv_data->rx_dma);
933 dma_enable_irq(drv_data->tx_dma);
934 bfin_write(&drv_data->regs->control, drv_data->control);
935 bfin_write(&drv_data->regs->ssel, drv_data->ssel);
936
937 ret = spi_master_resume(master);
938 if (ret) {
939 free_dma(drv_data->rx_dma);
940 free_dma(drv_data->tx_dma);
941 }
942
943 return ret;
944 }
945 #endif
946 static const struct dev_pm_ops bfin_spi_pm_ops = {
947 SET_SYSTEM_SLEEP_PM_OPS(bfin_spi_suspend, bfin_spi_resume)
948 };
949
950 MODULE_ALIAS("platform:bfin-spi3");
951 static struct platform_driver bfin_spi_driver = {
952 .driver = {
953 .name = "bfin-spi3",
954 .owner = THIS_MODULE,
955 .pm = &bfin_spi_pm_ops,
956 },
957 .remove = bfin_spi_remove,
958 };
959
960 module_platform_driver_probe(bfin_spi_driver, bfin_spi_probe);
961
962 MODULE_DESCRIPTION("Analog Devices SPI3 controller driver");
963 MODULE_AUTHOR("Scott Jiang <Scott.Jiang.Linux@gmail.com>");
964 MODULE_LICENSE("GPL v2");
Linux with added FPC-III support