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Linux 4.1.16
[linux/fpc-iii.git] / drivers / spi / spi-adi-v3.c
bloba16b25dcd1e6098355144fa1ff80cfc60d06f673
1 /*
2 * Analog Devices SPI3 controller driver
3 *
4 * Copyright (c) 2014 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/clk.h>
17 #include <linux/delay.h>
18 #include <linux/device.h>
19 #include <linux/dma-mapping.h>
20 #include <linux/errno.h>
21 #include <linux/gpio.h>
22 #include <linux/init.h>
23 #include <linux/interrupt.h>
24 #include <linux/io.h>
25 #include <linux/ioport.h>
26 #include <linux/module.h>
27 #include <linux/platform_device.h>
28 #include <linux/slab.h>
29 #include <linux/spi/spi.h>
30 #include <linux/spi/adi_spi3.h>
31 #include <linux/types.h>
32
33 #include <asm/dma.h>
34 #include <asm/portmux.h>
35
36 enum adi_spi_state {
37 START_STATE,
38 RUNNING_STATE,
39 DONE_STATE,
40 ERROR_STATE
41 };
42
43 struct adi_spi_master;
44
45 struct adi_spi_transfer_ops {
46 void (*write) (struct adi_spi_master *);
47 void (*read) (struct adi_spi_master *);
48 void (*duplex) (struct adi_spi_master *);
49 };
50
51 /* runtime info for spi master */
52 struct adi_spi_master {
53 /* SPI framework hookup */
54 struct spi_master *master;
55
56 /* Regs base of SPI controller */
57 struct adi_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 adi_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 adi_spi_state state;
94
95 const struct adi_spi_transfer_ops *ops;
96 };
97
98 struct adi_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 adi_spi_transfer_ops *ops;
109 };
110
111 static void adi_spi_enable(struct adi_spi_master *drv_data)
112 {
113 u32 ctl;
114
115 ctl = ioread32(&drv_data->regs->control);
116 ctl |= SPI_CTL_EN;
117 iowrite32(ctl, &drv_data->regs->control);
118 }
119
120 static void adi_spi_disable(struct adi_spi_master *drv_data)
121 {
122 u32 ctl;
123
124 ctl = ioread32(&drv_data->regs->control);
125 ctl &= ~SPI_CTL_EN;
126 iowrite32(ctl, &drv_data->regs->control);
127 }
128
129 /* Caculate the SPI_CLOCK register value based on input HZ */
130 static u32 hz_to_spi_clock(u32 sclk, u32 speed_hz)
131 {
132 u32 spi_clock = sclk / speed_hz;
133
134 if (spi_clock)
135 spi_clock--;
136 return spi_clock;
137 }
138
139 static int adi_spi_flush(struct adi_spi_master *drv_data)
140 {
141 unsigned long limit = loops_per_jiffy << 1;
142
143 /* wait for stop and clear stat */
144 while (!(ioread32(&drv_data->regs->status) & SPI_STAT_SPIF) && --limit)
145 cpu_relax();
146
147 iowrite32(0xFFFFFFFF, &drv_data->regs->status);
148
149 return limit;
150 }
151
152 /* Chip select operation functions for cs_change flag */
153 static void adi_spi_cs_active(struct adi_spi_master *drv_data, struct adi_spi_device *chip)
154 {
155 if (likely(chip->cs < MAX_CTRL_CS)) {
156 u32 reg;
157 reg = ioread32(&drv_data->regs->ssel);
158 reg &= ~chip->ssel;
159 iowrite32(reg, &drv_data->regs->ssel);
160 } else {
161 gpio_set_value(chip->cs_gpio, 0);
162 }
163 }
164
165 static void adi_spi_cs_deactive(struct adi_spi_master *drv_data,
166 struct adi_spi_device *chip)
167 {
168 if (likely(chip->cs < MAX_CTRL_CS)) {
169 u32 reg;
170 reg = ioread32(&drv_data->regs->ssel);
171 reg |= chip->ssel;
172 iowrite32(reg, &drv_data->regs->ssel);
173 } else {
174 gpio_set_value(chip->cs_gpio, 1);
175 }
176
177 /* Move delay here for consistency */
178 if (chip->cs_chg_udelay)
179 udelay(chip->cs_chg_udelay);
180 }
181
182 /* enable or disable the pin muxed by GPIO and SPI CS to work as SPI CS */
183 static inline void adi_spi_cs_enable(struct adi_spi_master *drv_data,
184 struct adi_spi_device *chip)
185 {
186 if (chip->cs < MAX_CTRL_CS) {
187 u32 reg;
188 reg = ioread32(&drv_data->regs->ssel);
189 reg |= chip->ssel >> 8;
190 iowrite32(reg, &drv_data->regs->ssel);
191 }
192 }
193
194 static inline void adi_spi_cs_disable(struct adi_spi_master *drv_data,
195 struct adi_spi_device *chip)
196 {
197 if (chip->cs < MAX_CTRL_CS) {
198 u32 reg;
199 reg = ioread32(&drv_data->regs->ssel);
200 reg &= ~(chip->ssel >> 8);
201 iowrite32(reg, &drv_data->regs->ssel);
202 }
203 }
204
205 /* stop controller and re-config current chip*/
206 static void adi_spi_restore_state(struct adi_spi_master *drv_data)
207 {
208 struct adi_spi_device *chip = drv_data->cur_chip;
209
210 /* Clear status and disable clock */
211 iowrite32(0xFFFFFFFF, &drv_data->regs->status);
212 iowrite32(0x0, &drv_data->regs->rx_control);
213 iowrite32(0x0, &drv_data->regs->tx_control);
214 adi_spi_disable(drv_data);
215
216 /* Load the registers */
217 iowrite32(chip->control, &drv_data->regs->control);
218 iowrite32(chip->clock, &drv_data->regs->clock);
219
220 adi_spi_enable(drv_data);
221 drv_data->tx_num = drv_data->rx_num = 0;
222 /* we always choose tx transfer initiate */
223 iowrite32(SPI_RXCTL_REN, &drv_data->regs->rx_control);
224 iowrite32(SPI_TXCTL_TEN | SPI_TXCTL_TTI, &drv_data->regs->tx_control);
225 adi_spi_cs_active(drv_data, chip);
226 }
227
228 /* discard invalid rx data and empty rfifo */
229 static inline void dummy_read(struct adi_spi_master *drv_data)
230 {
231 while (!(ioread32(&drv_data->regs->status) & SPI_STAT_RFE))
232 ioread32(&drv_data->regs->rfifo);
233 }
234
235 static void adi_spi_u8_write(struct adi_spi_master *drv_data)
236 {
237 dummy_read(drv_data);
238 while (drv_data->tx < drv_data->tx_end) {
239 iowrite32(*(u8 *)(drv_data->tx++), &drv_data->regs->tfifo);
240 while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE)
241 cpu_relax();
242 ioread32(&drv_data->regs->rfifo);
243 }
244 }
245
246 static void adi_spi_u8_read(struct adi_spi_master *drv_data)
247 {
248 u32 tx_val = drv_data->cur_chip->tx_dummy_val;
249
250 dummy_read(drv_data);
251 while (drv_data->rx < drv_data->rx_end) {
252 iowrite32(tx_val, &drv_data->regs->tfifo);
253 while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE)
254 cpu_relax();
255 *(u8 *)(drv_data->rx++) = ioread32(&drv_data->regs->rfifo);
256 }
257 }
258
259 static void adi_spi_u8_duplex(struct adi_spi_master *drv_data)
260 {
261 dummy_read(drv_data);
262 while (drv_data->rx < drv_data->rx_end) {
263 iowrite32(*(u8 *)(drv_data->tx++), &drv_data->regs->tfifo);
264 while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE)
265 cpu_relax();
266 *(u8 *)(drv_data->rx++) = ioread32(&drv_data->regs->rfifo);
267 }
268 }
269
270 static const struct adi_spi_transfer_ops adi_spi_transfer_ops_u8 = {
271 .write = adi_spi_u8_write,
272 .read = adi_spi_u8_read,
273 .duplex = adi_spi_u8_duplex,
274 };
275
276 static void adi_spi_u16_write(struct adi_spi_master *drv_data)
277 {
278 dummy_read(drv_data);
279 while (drv_data->tx < drv_data->tx_end) {
280 iowrite32(*(u16 *)drv_data->tx, &drv_data->regs->tfifo);
281 drv_data->tx += 2;
282 while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE)
283 cpu_relax();
284 ioread32(&drv_data->regs->rfifo);
285 }
286 }
287
288 static void adi_spi_u16_read(struct adi_spi_master *drv_data)
289 {
290 u32 tx_val = drv_data->cur_chip->tx_dummy_val;
291
292 dummy_read(drv_data);
293 while (drv_data->rx < drv_data->rx_end) {
294 iowrite32(tx_val, &drv_data->regs->tfifo);
295 while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE)
296 cpu_relax();
297 *(u16 *)drv_data->rx = ioread32(&drv_data->regs->rfifo);
298 drv_data->rx += 2;
299 }
300 }
301
302 static void adi_spi_u16_duplex(struct adi_spi_master *drv_data)
303 {
304 dummy_read(drv_data);
305 while (drv_data->rx < drv_data->rx_end) {
306 iowrite32(*(u16 *)drv_data->tx, &drv_data->regs->tfifo);
307 drv_data->tx += 2;
308 while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE)
309 cpu_relax();
310 *(u16 *)drv_data->rx = ioread32(&drv_data->regs->rfifo);
311 drv_data->rx += 2;
312 }
313 }
314
315 static const struct adi_spi_transfer_ops adi_spi_transfer_ops_u16 = {
316 .write = adi_spi_u16_write,
317 .read = adi_spi_u16_read,
318 .duplex = adi_spi_u16_duplex,
319 };
320
321 static void adi_spi_u32_write(struct adi_spi_master *drv_data)
322 {
323 dummy_read(drv_data);
324 while (drv_data->tx < drv_data->tx_end) {
325 iowrite32(*(u32 *)drv_data->tx, &drv_data->regs->tfifo);
326 drv_data->tx += 4;
327 while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE)
328 cpu_relax();
329 ioread32(&drv_data->regs->rfifo);
330 }
331 }
332
333 static void adi_spi_u32_read(struct adi_spi_master *drv_data)
334 {
335 u32 tx_val = drv_data->cur_chip->tx_dummy_val;
336
337 dummy_read(drv_data);
338 while (drv_data->rx < drv_data->rx_end) {
339 iowrite32(tx_val, &drv_data->regs->tfifo);
340 while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE)
341 cpu_relax();
342 *(u32 *)drv_data->rx = ioread32(&drv_data->regs->rfifo);
343 drv_data->rx += 4;
344 }
345 }
346
347 static void adi_spi_u32_duplex(struct adi_spi_master *drv_data)
348 {
349 dummy_read(drv_data);
350 while (drv_data->rx < drv_data->rx_end) {
351 iowrite32(*(u32 *)drv_data->tx, &drv_data->regs->tfifo);
352 drv_data->tx += 4;
353 while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE)
354 cpu_relax();
355 *(u32 *)drv_data->rx = ioread32(&drv_data->regs->rfifo);
356 drv_data->rx += 4;
357 }
358 }
359
360 static const struct adi_spi_transfer_ops adi_spi_transfer_ops_u32 = {
361 .write = adi_spi_u32_write,
362 .read = adi_spi_u32_read,
363 .duplex = adi_spi_u32_duplex,
364 };
365
366
367 /* test if there is more transfer to be done */
368 static void adi_spi_next_transfer(struct adi_spi_master *drv)
369 {
370 struct spi_message *msg = drv->cur_msg;
371 struct spi_transfer *t = drv->cur_transfer;
372
373 /* Move to next transfer */
374 if (t->transfer_list.next != &msg->transfers) {
375 drv->cur_transfer = list_entry(t->transfer_list.next,
376 struct spi_transfer, transfer_list);
377 drv->state = RUNNING_STATE;
378 } else {
379 drv->state = DONE_STATE;
380 drv->cur_transfer = NULL;
381 }
382 }
383
384 static void adi_spi_giveback(struct adi_spi_master *drv_data)
385 {
386 struct adi_spi_device *chip = drv_data->cur_chip;
387
388 adi_spi_cs_deactive(drv_data, chip);
389 spi_finalize_current_message(drv_data->master);
390 }
391
392 static int adi_spi_setup_transfer(struct adi_spi_master *drv)
393 {
394 struct spi_transfer *t = drv->cur_transfer;
395 u32 cr, cr_width;
396
397 if (t->tx_buf) {
398 drv->tx = (void *)t->tx_buf;
399 drv->tx_end = drv->tx + t->len;
400 } else {
401 drv->tx = NULL;
402 }
403
404 if (t->rx_buf) {
405 drv->rx = t->rx_buf;
406 drv->rx_end = drv->rx + t->len;
407 } else {
408 drv->rx = NULL;
409 }
410
411 drv->transfer_len = t->len;
412
413 /* bits per word setup */
414 switch (t->bits_per_word) {
415 case 8:
416 cr_width = SPI_CTL_SIZE08;
417 drv->ops = &adi_spi_transfer_ops_u8;
418 break;
419 case 16:
420 cr_width = SPI_CTL_SIZE16;
421 drv->ops = &adi_spi_transfer_ops_u16;
422 break;
423 case 32:
424 cr_width = SPI_CTL_SIZE32;
425 drv->ops = &adi_spi_transfer_ops_u32;
426 break;
427 default:
428 return -EINVAL;
429 }
430 cr = ioread32(&drv->regs->control) & ~SPI_CTL_SIZE;
431 cr |= cr_width;
432 iowrite32(cr, &drv->regs->control);
433
434 /* speed setup */
435 iowrite32(hz_to_spi_clock(drv->sclk, t->speed_hz), &drv->regs->clock);
436 return 0;
437 }
438
439 static int adi_spi_dma_xfer(struct adi_spi_master *drv_data)
440 {
441 struct spi_transfer *t = drv_data->cur_transfer;
442 struct spi_message *msg = drv_data->cur_msg;
443 struct adi_spi_device *chip = drv_data->cur_chip;
444 u32 dma_config;
445 unsigned long word_count, word_size;
446 void *tx_buf, *rx_buf;
447
448 switch (t->bits_per_word) {
449 case 8:
450 dma_config = WDSIZE_8 | PSIZE_8;
451 word_count = drv_data->transfer_len;
452 word_size = 1;
453 break;
454 case 16:
455 dma_config = WDSIZE_16 | PSIZE_16;
456 word_count = drv_data->transfer_len / 2;
457 word_size = 2;
458 break;
459 default:
460 dma_config = WDSIZE_32 | PSIZE_32;
461 word_count = drv_data->transfer_len / 4;
462 word_size = 4;
463 break;
464 }
465
466 if (!drv_data->rx) {
467 tx_buf = drv_data->tx;
468 rx_buf = &drv_data->dummy_buffer;
469 drv_data->tx_dma_size = drv_data->transfer_len;
470 drv_data->rx_dma_size = sizeof(drv_data->dummy_buffer);
471 set_dma_x_modify(drv_data->tx_dma, word_size);
472 set_dma_x_modify(drv_data->rx_dma, 0);
473 } else if (!drv_data->tx) {
474 drv_data->dummy_buffer = chip->tx_dummy_val;
475 tx_buf = &drv_data->dummy_buffer;
476 rx_buf = drv_data->rx;
477 drv_data->tx_dma_size = sizeof(drv_data->dummy_buffer);
478 drv_data->rx_dma_size = drv_data->transfer_len;
479 set_dma_x_modify(drv_data->tx_dma, 0);
480 set_dma_x_modify(drv_data->rx_dma, word_size);
481 } else {
482 tx_buf = drv_data->tx;
483 rx_buf = drv_data->rx;
484 drv_data->tx_dma_size = drv_data->rx_dma_size
485 = drv_data->transfer_len;
486 set_dma_x_modify(drv_data->tx_dma, word_size);
487 set_dma_x_modify(drv_data->rx_dma, word_size);
488 }
489
490 drv_data->tx_dma_addr = dma_map_single(&msg->spi->dev,
491 (void *)tx_buf,
492 drv_data->tx_dma_size,
493 DMA_TO_DEVICE);
494 if (dma_mapping_error(&msg->spi->dev,
495 drv_data->tx_dma_addr))
496 return -ENOMEM;
497
498 drv_data->rx_dma_addr = dma_map_single(&msg->spi->dev,
499 (void *)rx_buf,
500 drv_data->rx_dma_size,
501 DMA_FROM_DEVICE);
502 if (dma_mapping_error(&msg->spi->dev,
503 drv_data->rx_dma_addr)) {
504 dma_unmap_single(&msg->spi->dev,
505 drv_data->tx_dma_addr,
506 drv_data->tx_dma_size,
507 DMA_TO_DEVICE);
508 return -ENOMEM;
509 }
510
511 dummy_read(drv_data);
512 set_dma_x_count(drv_data->tx_dma, word_count);
513 set_dma_x_count(drv_data->rx_dma, word_count);
514 set_dma_start_addr(drv_data->tx_dma, drv_data->tx_dma_addr);
515 set_dma_start_addr(drv_data->rx_dma, drv_data->rx_dma_addr);
516 dma_config |= DMAFLOW_STOP | RESTART | DI_EN;
517 set_dma_config(drv_data->tx_dma, dma_config);
518 set_dma_config(drv_data->rx_dma, dma_config | WNR);
519 enable_dma(drv_data->tx_dma);
520 enable_dma(drv_data->rx_dma);
521
522 iowrite32(SPI_RXCTL_REN | SPI_RXCTL_RDR_NE,
523 &drv_data->regs->rx_control);
524 iowrite32(SPI_TXCTL_TEN | SPI_TXCTL_TTI | SPI_TXCTL_TDR_NF,
525 &drv_data->regs->tx_control);
526
527 return 0;
528 }
529
530 static int adi_spi_pio_xfer(struct adi_spi_master *drv_data)
531 {
532 struct spi_message *msg = drv_data->cur_msg;
533
534 if (!drv_data->rx) {
535 /* write only half duplex */
536 drv_data->ops->write(drv_data);
537 if (drv_data->tx != drv_data->tx_end)
538 return -EIO;
539 } else if (!drv_data->tx) {
540 /* read only half duplex */
541 drv_data->ops->read(drv_data);
542 if (drv_data->rx != drv_data->rx_end)
543 return -EIO;
544 } else {
545 /* full duplex mode */
546 drv_data->ops->duplex(drv_data);
547 if (drv_data->tx != drv_data->tx_end)
548 return -EIO;
549 }
550
551 if (!adi_spi_flush(drv_data))
552 return -EIO;
553 msg->actual_length += drv_data->transfer_len;
554 tasklet_schedule(&drv_data->pump_transfers);
555 return 0;
556 }
557
558 static void adi_spi_pump_transfers(unsigned long data)
559 {
560 struct adi_spi_master *drv_data = (struct adi_spi_master *)data;
561 struct spi_message *msg = NULL;
562 struct spi_transfer *t = NULL;
563 struct adi_spi_device *chip = NULL;
564 int ret;
565
566 /* Get current state information */
567 msg = drv_data->cur_msg;
568 t = drv_data->cur_transfer;
569 chip = drv_data->cur_chip;
570
571 /* Handle for abort */
572 if (drv_data->state == ERROR_STATE) {
573 msg->status = -EIO;
574 adi_spi_giveback(drv_data);
575 return;
576 }
577
578 if (drv_data->state == RUNNING_STATE) {
579 if (t->delay_usecs)
580 udelay(t->delay_usecs);
581 if (t->cs_change)
582 adi_spi_cs_deactive(drv_data, chip);
583 adi_spi_next_transfer(drv_data);
584 t = drv_data->cur_transfer;
585 }
586 /* Handle end of message */
587 if (drv_data->state == DONE_STATE) {
588 msg->status = 0;
589 adi_spi_giveback(drv_data);
590 return;
591 }
592
593 if ((t->len == 0) || (t->tx_buf == NULL && t->rx_buf == NULL)) {
594 /* Schedule next transfer tasklet */
595 tasklet_schedule(&drv_data->pump_transfers);
596 return;
597 }
598
599 ret = adi_spi_setup_transfer(drv_data);
600 if (ret) {
601 msg->status = ret;
602 adi_spi_giveback(drv_data);
603 }
604
605 iowrite32(0xFFFFFFFF, &drv_data->regs->status);
606 adi_spi_cs_active(drv_data, chip);
607 drv_data->state = RUNNING_STATE;
608
609 if (chip->enable_dma)
610 ret = adi_spi_dma_xfer(drv_data);
611 else
612 ret = adi_spi_pio_xfer(drv_data);
613 if (ret) {
614 msg->status = ret;
615 adi_spi_giveback(drv_data);
616 }
617 }
618
619 static int adi_spi_transfer_one_message(struct spi_master *master,
620 struct spi_message *m)
621 {
622 struct adi_spi_master *drv_data = spi_master_get_devdata(master);
623
624 drv_data->cur_msg = m;
625 drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi);
626 adi_spi_restore_state(drv_data);
627
628 drv_data->state = START_STATE;
629 drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next,
630 struct spi_transfer, transfer_list);
631
632 tasklet_schedule(&drv_data->pump_transfers);
633 return 0;
634 }
635
636 #define MAX_SPI_SSEL 7
637
638 static const u16 ssel[][MAX_SPI_SSEL] = {
639 {P_SPI0_SSEL1, P_SPI0_SSEL2, P_SPI0_SSEL3,
640 P_SPI0_SSEL4, P_SPI0_SSEL5,
641 P_SPI0_SSEL6, P_SPI0_SSEL7},
642
643 {P_SPI1_SSEL1, P_SPI1_SSEL2, P_SPI1_SSEL3,
644 P_SPI1_SSEL4, P_SPI1_SSEL5,
645 P_SPI1_SSEL6, P_SPI1_SSEL7},
646
647 {P_SPI2_SSEL1, P_SPI2_SSEL2, P_SPI2_SSEL3,
648 P_SPI2_SSEL4, P_SPI2_SSEL5,
649 P_SPI2_SSEL6, P_SPI2_SSEL7},
650 };
651
652 static int adi_spi_setup(struct spi_device *spi)
653 {
654 struct adi_spi_master *drv_data = spi_master_get_devdata(spi->master);
655 struct adi_spi_device *chip = spi_get_ctldata(spi);
656 u32 ctl_reg = SPI_CTL_ODM | SPI_CTL_PSSE;
657 int ret = -EINVAL;
658
659 if (!chip) {
660 struct adi_spi3_chip *chip_info = spi->controller_data;
661
662 chip = kzalloc(sizeof(*chip), GFP_KERNEL);
663 if (!chip)
664 return -ENOMEM;
665
666 if (chip_info) {
667 if (chip_info->control & ~ctl_reg) {
668 dev_err(&spi->dev,
669 "do not set bits that the SPI framework manages\n");
670 goto error;
671 }
672 chip->control = chip_info->control;
673 chip->cs_chg_udelay = chip_info->cs_chg_udelay;
674 chip->tx_dummy_val = chip_info->tx_dummy_val;
675 chip->enable_dma = chip_info->enable_dma;
676 }
677 chip->cs = spi->chip_select;
678
679 if (chip->cs < MAX_CTRL_CS) {
680 chip->ssel = (1 << chip->cs) << 8;
681 ret = peripheral_request(ssel[spi->master->bus_num]
682 [chip->cs-1], dev_name(&spi->dev));
683 if (ret) {
684 dev_err(&spi->dev, "peripheral_request() error\n");
685 goto error;
686 }
687 } else {
688 chip->cs_gpio = chip->cs - MAX_CTRL_CS;
689 ret = gpio_request_one(chip->cs_gpio, GPIOF_OUT_INIT_HIGH,
690 dev_name(&spi->dev));
691 if (ret) {
692 dev_err(&spi->dev, "gpio_request_one() error\n");
693 goto error;
694 }
695 }
696 spi_set_ctldata(spi, chip);
697 }
698
699 /* force a default base state */
700 chip->control &= ctl_reg;
701
702 if (spi->mode & SPI_CPOL)
703 chip->control |= SPI_CTL_CPOL;
704 if (spi->mode & SPI_CPHA)
705 chip->control |= SPI_CTL_CPHA;
706 if (spi->mode & SPI_LSB_FIRST)
707 chip->control |= SPI_CTL_LSBF;
708 chip->control |= SPI_CTL_MSTR;
709 /* we choose software to controll cs */
710 chip->control &= ~SPI_CTL_ASSEL;
711
712 chip->clock = hz_to_spi_clock(drv_data->sclk, spi->max_speed_hz);
713
714 adi_spi_cs_enable(drv_data, chip);
715 adi_spi_cs_deactive(drv_data, chip);
716
717 return 0;
718 error:
719 if (chip) {
720 kfree(chip);
721 spi_set_ctldata(spi, NULL);
722 }
723
724 return ret;
725 }
726
727 static void adi_spi_cleanup(struct spi_device *spi)
728 {
729 struct adi_spi_device *chip = spi_get_ctldata(spi);
730 struct adi_spi_master *drv_data = spi_master_get_devdata(spi->master);
731
732 if (!chip)
733 return;
734
735 if (chip->cs < MAX_CTRL_CS) {
736 peripheral_free(ssel[spi->master->bus_num]
737 [chip->cs-1]);
738 adi_spi_cs_disable(drv_data, chip);
739 } else {
740 gpio_free(chip->cs_gpio);
741 }
742
743 kfree(chip);
744 spi_set_ctldata(spi, NULL);
745 }
746
747 static irqreturn_t adi_spi_tx_dma_isr(int irq, void *dev_id)
748 {
749 struct adi_spi_master *drv_data = dev_id;
750 u32 dma_stat = get_dma_curr_irqstat(drv_data->tx_dma);
751 u32 tx_ctl;
752
753 clear_dma_irqstat(drv_data->tx_dma);
754 if (dma_stat & DMA_DONE) {
755 drv_data->tx_num++;
756 } else {
757 dev_err(&drv_data->master->dev,
758 "spi tx dma error: %d\n", dma_stat);
759 if (drv_data->tx)
760 drv_data->state = ERROR_STATE;
761 }
762 tx_ctl = ioread32(&drv_data->regs->tx_control);
763 tx_ctl &= ~SPI_TXCTL_TDR_NF;
764 iowrite32(tx_ctl, &drv_data->regs->tx_control);
765 return IRQ_HANDLED;
766 }
767
768 static irqreturn_t adi_spi_rx_dma_isr(int irq, void *dev_id)
769 {
770 struct adi_spi_master *drv_data = dev_id;
771 struct spi_message *msg = drv_data->cur_msg;
772 u32 dma_stat = get_dma_curr_irqstat(drv_data->rx_dma);
773
774 clear_dma_irqstat(drv_data->rx_dma);
775 if (dma_stat & DMA_DONE) {
776 drv_data->rx_num++;
777 /* we may fail on tx dma */
778 if (drv_data->state != ERROR_STATE)
779 msg->actual_length += drv_data->transfer_len;
780 } else {
781 drv_data->state = ERROR_STATE;
782 dev_err(&drv_data->master->dev,
783 "spi rx dma error: %d\n", dma_stat);
784 }
785 iowrite32(0, &drv_data->regs->tx_control);
786 iowrite32(0, &drv_data->regs->rx_control);
787 if (drv_data->rx_num != drv_data->tx_num)
788 dev_dbg(&drv_data->master->dev,
789 "dma interrupt missing: tx=%d,rx=%d\n",
790 drv_data->tx_num, drv_data->rx_num);
791 tasklet_schedule(&drv_data->pump_transfers);
792 return IRQ_HANDLED;
793 }
794
795 static int adi_spi_probe(struct platform_device *pdev)
796 {
797 struct device *dev = &pdev->dev;
798 struct adi_spi3_master *info = dev_get_platdata(dev);
799 struct spi_master *master;
800 struct adi_spi_master *drv_data;
801 struct resource *mem, *res;
802 unsigned int tx_dma, rx_dma;
803 struct clk *sclk;
804 int ret;
805
806 if (!info) {
807 dev_err(dev, "platform data missing!\n");
808 return -ENODEV;
809 }
810
811 sclk = devm_clk_get(dev, "spi");
812 if (IS_ERR(sclk)) {
813 dev_err(dev, "can not get spi clock\n");
814 return PTR_ERR(sclk);
815 }
816
817 res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
818 if (!res) {
819 dev_err(dev, "can not get tx dma resource\n");
820 return -ENXIO;
821 }
822 tx_dma = res->start;
823
824 res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
825 if (!res) {
826 dev_err(dev, "can not get rx dma resource\n");
827 return -ENXIO;
828 }
829 rx_dma = res->start;
830
831 /* allocate master with space for drv_data */
832 master = spi_alloc_master(dev, sizeof(*drv_data));
833 if (!master) {
834 dev_err(dev, "can not alloc spi_master\n");
835 return -ENOMEM;
836 }
837 platform_set_drvdata(pdev, master);
838
839 /* the mode bits supported by this driver */
840 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
841
842 master->bus_num = pdev->id;
843 master->num_chipselect = info->num_chipselect;
844 master->cleanup = adi_spi_cleanup;
845 master->setup = adi_spi_setup;
846 master->transfer_one_message = adi_spi_transfer_one_message;
847 master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) |
848 SPI_BPW_MASK(8);
849
850 drv_data = spi_master_get_devdata(master);
851 drv_data->master = master;
852 drv_data->tx_dma = tx_dma;
853 drv_data->rx_dma = rx_dma;
854 drv_data->pin_req = info->pin_req;
855 drv_data->sclk = clk_get_rate(sclk);
856
857 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
858 drv_data->regs = devm_ioremap_resource(dev, mem);
859 if (IS_ERR(drv_data->regs)) {
860 ret = PTR_ERR(drv_data->regs);
861 goto err_put_master;
862 }
863
864 /* request tx and rx dma */
865 ret = request_dma(tx_dma, "SPI_TX_DMA");
866 if (ret) {
867 dev_err(dev, "can not request SPI TX DMA channel\n");
868 goto err_put_master;
869 }
870 set_dma_callback(tx_dma, adi_spi_tx_dma_isr, drv_data);
871
872 ret = request_dma(rx_dma, "SPI_RX_DMA");
873 if (ret) {
874 dev_err(dev, "can not request SPI RX DMA channel\n");
875 goto err_free_tx_dma;
876 }
877 set_dma_callback(drv_data->rx_dma, adi_spi_rx_dma_isr, drv_data);
878
879 /* request CLK, MOSI and MISO */
880 ret = peripheral_request_list(drv_data->pin_req, "adi-spi3");
881 if (ret < 0) {
882 dev_err(dev, "can not request spi pins\n");
883 goto err_free_rx_dma;
884 }
885
886 iowrite32(SPI_CTL_MSTR | SPI_CTL_CPHA, &drv_data->regs->control);
887 iowrite32(0x0000FE00, &drv_data->regs->ssel);
888 iowrite32(0x0, &drv_data->regs->delay);
889
890 tasklet_init(&drv_data->pump_transfers,
891 adi_spi_pump_transfers, (unsigned long)drv_data);
892 /* register with the SPI framework */
893 ret = devm_spi_register_master(dev, master);
894 if (ret) {
895 dev_err(dev, "can not register spi master\n");
896 goto err_free_peripheral;
897 }
898
899 return ret;
900
901 err_free_peripheral:
902 peripheral_free_list(drv_data->pin_req);
903 err_free_rx_dma:
904 free_dma(rx_dma);
905 err_free_tx_dma:
906 free_dma(tx_dma);
907 err_put_master:
908 spi_master_put(master);
909
910 return ret;
911 }
912
913 static int adi_spi_remove(struct platform_device *pdev)
914 {
915 struct spi_master *master = platform_get_drvdata(pdev);
916 struct adi_spi_master *drv_data = spi_master_get_devdata(master);
917
918 adi_spi_disable(drv_data);
919 peripheral_free_list(drv_data->pin_req);
920 free_dma(drv_data->rx_dma);
921 free_dma(drv_data->tx_dma);
922 return 0;
923 }
924
925 #ifdef CONFIG_PM
926 static int adi_spi_suspend(struct device *dev)
927 {
928 struct spi_master *master = dev_get_drvdata(dev);
929 struct adi_spi_master *drv_data = spi_master_get_devdata(master);
930
931 spi_master_suspend(master);
932
933 drv_data->control = ioread32(&drv_data->regs->control);
934 drv_data->ssel = ioread32(&drv_data->regs->ssel);
935
936 iowrite32(SPI_CTL_MSTR | SPI_CTL_CPHA, &drv_data->regs->control);
937 iowrite32(0x0000FE00, &drv_data->regs->ssel);
938 dma_disable_irq(drv_data->rx_dma);
939 dma_disable_irq(drv_data->tx_dma);
940
941 return 0;
942 }
943
944 static int adi_spi_resume(struct device *dev)
945 {
946 struct spi_master *master = dev_get_drvdata(dev);
947 struct adi_spi_master *drv_data = spi_master_get_devdata(master);
948 int ret = 0;
949
950 /* bootrom may modify spi and dma status when resume in spi boot mode */
951 disable_dma(drv_data->rx_dma);
952
953 dma_enable_irq(drv_data->rx_dma);
954 dma_enable_irq(drv_data->tx_dma);
955 iowrite32(drv_data->control, &drv_data->regs->control);
956 iowrite32(drv_data->ssel, &drv_data->regs->ssel);
957
958 ret = spi_master_resume(master);
959 if (ret) {
960 free_dma(drv_data->rx_dma);
961 free_dma(drv_data->tx_dma);
962 }
963
964 return ret;
965 }
966 #endif
967 static const struct dev_pm_ops adi_spi_pm_ops = {
968 SET_SYSTEM_SLEEP_PM_OPS(adi_spi_suspend, adi_spi_resume)
969 };
970
971 MODULE_ALIAS("platform:adi-spi3");
972 static struct platform_driver adi_spi_driver = {
973 .driver = {
974 .name = "adi-spi3",
975 .pm = &adi_spi_pm_ops,
976 },
977 .remove = adi_spi_remove,
978 };
979
980 module_platform_driver_probe(adi_spi_driver, adi_spi_probe);
981
982 MODULE_DESCRIPTION("Analog Devices SPI3 controller driver");
983 MODULE_AUTHOR("Scott Jiang <Scott.Jiang.Linux@gmail.com>");
984 MODULE_LICENSE("GPL v2");
Linux with added FPC-III support