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1/*
2 * SuperH MSIOF SPI Master Interface
3 *
4 * Copyright (c) 2009 Magnus Damm
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 */
11
12#include <linux/bitmap.h>
13#include <linux/clk.h>
14#include <linux/completion.h>
15#include <linux/delay.h>
16#include <linux/err.h>
17#include <linux/gpio.h>
18#include <linux/init.h>
19#include <linux/interrupt.h>
20#include <linux/io.h>
21#include <linux/kernel.h>
22#include <linux/platform_device.h>
23#include <linux/pm_runtime.h>
24
25#include <linux/spi/sh_msiof.h>
26#include <linux/spi/spi.h>
27#include <linux/spi/spi_bitbang.h>
28
29#include <asm/unaligned.h>
30
31struct sh_msiof_spi_priv {
32 struct spi_bitbang bitbang; /* must be first for spi_bitbang.c */
33 void __iomem *mapbase;
34 struct clk *clk;
35 struct platform_device *pdev;
36 struct sh_msiof_spi_info *info;
37 struct completion done;
38 unsigned long flags;
39 int tx_fifo_size;
40 int rx_fifo_size;
41};
42
43#define TMDR1 0x00
44#define TMDR2 0x04
45#define TMDR3 0x08
46#define RMDR1 0x10
47#define RMDR2 0x14
48#define RMDR3 0x18
49#define TSCR 0x20
50#define RSCR 0x22
51#define CTR 0x28
52#define FCTR 0x30
53#define STR 0x40
54#define IER 0x44
55#define TDR1 0x48
56#define TDR2 0x4c
57#define TFDR 0x50
58#define RDR1 0x58
59#define RDR2 0x5c
60#define RFDR 0x60
61
62#define CTR_TSCKE (1 << 15)
63#define CTR_TFSE (1 << 14)
64#define CTR_TXE (1 << 9)
65#define CTR_RXE (1 << 8)
66
67#define STR_TEOF (1 << 23)
68#define STR_REOF (1 << 7)
69
70static u32 sh_msiof_read(struct sh_msiof_spi_priv *p, int reg_offs)
71{
72 switch (reg_offs) {
73 case TSCR:
74 case RSCR:
75 return ioread16(p->mapbase + reg_offs);
76 default:
77 return ioread32(p->mapbase + reg_offs);
78 }
79}
80
81static void sh_msiof_write(struct sh_msiof_spi_priv *p, int reg_offs,
82 u32 value)
83{
84 switch (reg_offs) {
85 case TSCR:
86 case RSCR:
87 iowrite16(value, p->mapbase + reg_offs);
88 break;
89 default:
90 iowrite32(value, p->mapbase + reg_offs);
91 break;
92 }
93}
94
95static int sh_msiof_modify_ctr_wait(struct sh_msiof_spi_priv *p,
96 u32 clr, u32 set)
97{
98 u32 mask = clr | set;
99 u32 data;
100 int k;
101
102 data = sh_msiof_read(p, CTR);
103 data &= ~clr;
104 data |= set;
105 sh_msiof_write(p, CTR, data);
106
107 for (k = 100; k > 0; k--) {
108 if ((sh_msiof_read(p, CTR) & mask) == set)
109 break;
110
111 udelay(10);
112 }
113
114 return k > 0 ? 0 : -ETIMEDOUT;
115}
116
117static irqreturn_t sh_msiof_spi_irq(int irq, void *data)
118{
119 struct sh_msiof_spi_priv *p = data;
120
121 /* just disable the interrupt and wake up */
122 sh_msiof_write(p, IER, 0);
123 complete(&p->done);
124
125 return IRQ_HANDLED;
126}
127
128static struct {
129 unsigned short div;
130 unsigned short scr;
131} const sh_msiof_spi_clk_table[] = {
132 { 1, 0x0007 },
133 { 2, 0x0000 },
134 { 4, 0x0001 },
135 { 8, 0x0002 },
136 { 16, 0x0003 },
137 { 32, 0x0004 },
138 { 64, 0x1f00 },
139 { 128, 0x1f01 },
140 { 256, 0x1f02 },
141 { 512, 0x1f03 },
142 { 1024, 0x1f04 },
143};
144
145static void sh_msiof_spi_set_clk_regs(struct sh_msiof_spi_priv *p,
146 unsigned long parent_rate,
147 unsigned long spi_hz)
148{
149 unsigned long div = 1024;
150 size_t k;
151
152 if (!WARN_ON(!spi_hz || !parent_rate))
153 div = parent_rate / spi_hz;
154
155 /* TODO: make more fine grained */
156
157 for (k = 0; k < ARRAY_SIZE(sh_msiof_spi_clk_table); k++) {
158 if (sh_msiof_spi_clk_table[k].div >= div)
159 break;
160 }
161
162 k = min_t(int, k, ARRAY_SIZE(sh_msiof_spi_clk_table) - 1);
163
164 sh_msiof_write(p, TSCR, sh_msiof_spi_clk_table[k].scr);
165 sh_msiof_write(p, RSCR, sh_msiof_spi_clk_table[k].scr);
166}
167
168static void sh_msiof_spi_set_pin_regs(struct sh_msiof_spi_priv *p,
169 u32 cpol, u32 cpha,
170 u32 tx_hi_z, u32 lsb_first)
171{
172 u32 tmp;
173 int edge;
174
175 /*
176 * CPOL CPHA TSCKIZ RSCKIZ TEDG REDG
177 * 0 0 10 10 1 1
178 * 0 1 10 10 0 0
179 * 1 0 11 11 0 0
180 * 1 1 11 11 1 1
181 */
182 sh_msiof_write(p, FCTR, 0);
183 sh_msiof_write(p, TMDR1, 0xe2000005 | (lsb_first << 24));
184 sh_msiof_write(p, RMDR1, 0x22000005 | (lsb_first << 24));
185
186 tmp = 0xa0000000;
187 tmp |= cpol << 30; /* TSCKIZ */
188 tmp |= cpol << 28; /* RSCKIZ */
189
190 edge = cpol ^ !cpha;
191
192 tmp |= edge << 27; /* TEDG */
193 tmp |= edge << 26; /* REDG */
194 tmp |= (tx_hi_z ? 2 : 0) << 22; /* TXDIZ */
195 sh_msiof_write(p, CTR, tmp);
196}
197
198static void sh_msiof_spi_set_mode_regs(struct sh_msiof_spi_priv *p,
199 const void *tx_buf, void *rx_buf,
200 u32 bits, u32 words)
201{
202 u32 dr2 = ((bits - 1) << 24) | ((words - 1) << 16);
203
204 if (tx_buf)
205 sh_msiof_write(p, TMDR2, dr2);
206 else
207 sh_msiof_write(p, TMDR2, dr2 | 1);
208
209 if (rx_buf)
210 sh_msiof_write(p, RMDR2, dr2);
211
212 sh_msiof_write(p, IER, STR_TEOF | STR_REOF);
213}
214
215static void sh_msiof_reset_str(struct sh_msiof_spi_priv *p)
216{
217 sh_msiof_write(p, STR, sh_msiof_read(p, STR));
218}
219
220static void sh_msiof_spi_write_fifo_8(struct sh_msiof_spi_priv *p,
221 const void *tx_buf, int words, int fs)
222{
223 const u8 *buf_8 = tx_buf;
224 int k;
225
226 for (k = 0; k < words; k++)
227 sh_msiof_write(p, TFDR, buf_8[k] << fs);
228}
229
230static void sh_msiof_spi_write_fifo_16(struct sh_msiof_spi_priv *p,
231 const void *tx_buf, int words, int fs)
232{
233 const u16 *buf_16 = tx_buf;
234 int k;
235
236 for (k = 0; k < words; k++)
237 sh_msiof_write(p, TFDR, buf_16[k] << fs);
238}
239
240static void sh_msiof_spi_write_fifo_16u(struct sh_msiof_spi_priv *p,
241 const void *tx_buf, int words, int fs)
242{
243 const u16 *buf_16 = tx_buf;
244 int k;
245
246 for (k = 0; k < words; k++)
247 sh_msiof_write(p, TFDR, get_unaligned(&buf_16[k]) << fs);
248}
249
250static void sh_msiof_spi_write_fifo_32(struct sh_msiof_spi_priv *p,
251 const void *tx_buf, int words, int fs)
252{
253 const u32 *buf_32 = tx_buf;
254 int k;
255
256 for (k = 0; k < words; k++)
257 sh_msiof_write(p, TFDR, buf_32[k] << fs);
258}
259
260static void sh_msiof_spi_write_fifo_32u(struct sh_msiof_spi_priv *p,
261 const void *tx_buf, int words, int fs)
262{
263 const u32 *buf_32 = tx_buf;
264 int k;
265
266 for (k = 0; k < words; k++)
267 sh_msiof_write(p, TFDR, get_unaligned(&buf_32[k]) << fs);
268}
269
270static void sh_msiof_spi_write_fifo_s32(struct sh_msiof_spi_priv *p,
271 const void *tx_buf, int words, int fs)
272{
273 const u32 *buf_32 = tx_buf;
274 int k;
275
276 for (k = 0; k < words; k++)
277 sh_msiof_write(p, TFDR, swab32(buf_32[k] << fs));
278}
279
280static void sh_msiof_spi_write_fifo_s32u(struct sh_msiof_spi_priv *p,
281 const void *tx_buf, int words, int fs)
282{
283 const u32 *buf_32 = tx_buf;
284 int k;
285
286 for (k = 0; k < words; k++)
287 sh_msiof_write(p, TFDR, swab32(get_unaligned(&buf_32[k]) << fs));
288}
289
290static void sh_msiof_spi_read_fifo_8(struct sh_msiof_spi_priv *p,
291 void *rx_buf, int words, int fs)
292{
293 u8 *buf_8 = rx_buf;
294 int k;
295
296 for (k = 0; k < words; k++)
297 buf_8[k] = sh_msiof_read(p, RFDR) >> fs;
298}
299
300static void sh_msiof_spi_read_fifo_16(struct sh_msiof_spi_priv *p,
301 void *rx_buf, int words, int fs)
302{
303 u16 *buf_16 = rx_buf;
304 int k;
305
306 for (k = 0; k < words; k++)
307 buf_16[k] = sh_msiof_read(p, RFDR) >> fs;
308}
309
310static void sh_msiof_spi_read_fifo_16u(struct sh_msiof_spi_priv *p,
311 void *rx_buf, int words, int fs)
312{
313 u16 *buf_16 = rx_buf;
314 int k;
315
316 for (k = 0; k < words; k++)
317 put_unaligned(sh_msiof_read(p, RFDR) >> fs, &buf_16[k]);
318}
319
320static void sh_msiof_spi_read_fifo_32(struct sh_msiof_spi_priv *p,
321 void *rx_buf, int words, int fs)
322{
323 u32 *buf_32 = rx_buf;
324 int k;
325
326 for (k = 0; k < words; k++)
327 buf_32[k] = sh_msiof_read(p, RFDR) >> fs;
328}
329
330static void sh_msiof_spi_read_fifo_32u(struct sh_msiof_spi_priv *p,
331 void *rx_buf, int words, int fs)
332{
333 u32 *buf_32 = rx_buf;
334 int k;
335
336 for (k = 0; k < words; k++)
337 put_unaligned(sh_msiof_read(p, RFDR) >> fs, &buf_32[k]);
338}
339
340static void sh_msiof_spi_read_fifo_s32(struct sh_msiof_spi_priv *p,
341 void *rx_buf, int words, int fs)
342{
343 u32 *buf_32 = rx_buf;
344 int k;
345
346 for (k = 0; k < words; k++)
347 buf_32[k] = swab32(sh_msiof_read(p, RFDR) >> fs);
348}
349
350static void sh_msiof_spi_read_fifo_s32u(struct sh_msiof_spi_priv *p,
351 void *rx_buf, int words, int fs)
352{
353 u32 *buf_32 = rx_buf;
354 int k;
355
356 for (k = 0; k < words; k++)
357 put_unaligned(swab32(sh_msiof_read(p, RFDR) >> fs), &buf_32[k]);
358}
359
360static int sh_msiof_spi_bits(struct spi_device *spi, struct spi_transfer *t)
361{
362 int bits;
363
364 bits = t ? t->bits_per_word : 0;
365 if (!bits)
366 bits = spi->bits_per_word;
367 return bits;
368}
369
370static unsigned long sh_msiof_spi_hz(struct spi_device *spi,
371 struct spi_transfer *t)
372{
373 unsigned long hz;
374
375 hz = t ? t->speed_hz : 0;
376 if (!hz)
377 hz = spi->max_speed_hz;
378 return hz;
379}
380
381static int sh_msiof_spi_setup_transfer(struct spi_device *spi,
382 struct spi_transfer *t)
383{
384 int bits;
385
386 /* noting to check hz values against since parent clock is disabled */
387
388 bits = sh_msiof_spi_bits(spi, t);
389 if (bits < 8)
390 return -EINVAL;
391 if (bits > 32)
392 return -EINVAL;
393
394 return spi_bitbang_setup_transfer(spi, t);
395}
396
397static void sh_msiof_spi_chipselect(struct spi_device *spi, int is_on)
398{
399 struct sh_msiof_spi_priv *p = spi_master_get_devdata(spi->master);
400 int value;
401
402 /* chip select is active low unless SPI_CS_HIGH is set */
403 if (spi->mode & SPI_CS_HIGH)
404 value = (is_on == BITBANG_CS_ACTIVE) ? 1 : 0;
405 else
406 value = (is_on == BITBANG_CS_ACTIVE) ? 0 : 1;
407
408 if (is_on == BITBANG_CS_ACTIVE) {
409 if (!test_and_set_bit(0, &p->flags)) {
410 pm_runtime_get_sync(&p->pdev->dev);
411 clk_enable(p->clk);
412 }
413
414 /* Configure pins before asserting CS */
415 sh_msiof_spi_set_pin_regs(p, !!(spi->mode & SPI_CPOL),
416 !!(spi->mode & SPI_CPHA),
417 !!(spi->mode & SPI_3WIRE),
418 !!(spi->mode & SPI_LSB_FIRST));
419 }
420
421 /* use spi->controller data for CS (same strategy as spi_gpio) */
422 gpio_set_value((unsigned)spi->controller_data, value);
423
424 if (is_on == BITBANG_CS_INACTIVE) {
425 if (test_and_clear_bit(0, &p->flags)) {
426 clk_disable(p->clk);
427 pm_runtime_put(&p->pdev->dev);
428 }
429 }
430}
431
432static int sh_msiof_spi_txrx_once(struct sh_msiof_spi_priv *p,
433 void (*tx_fifo)(struct sh_msiof_spi_priv *,
434 const void *, int, int),
435 void (*rx_fifo)(struct sh_msiof_spi_priv *,
436 void *, int, int),
437 const void *tx_buf, void *rx_buf,
438 int words, int bits)
439{
440 int fifo_shift;
441 int ret;
442
443 /* limit maximum word transfer to rx/tx fifo size */
444 if (tx_buf)
445 words = min_t(int, words, p->tx_fifo_size);
446 if (rx_buf)
447 words = min_t(int, words, p->rx_fifo_size);
448
449 /* the fifo contents need shifting */
450 fifo_shift = 32 - bits;
451
452 /* setup msiof transfer mode registers */
453 sh_msiof_spi_set_mode_regs(p, tx_buf, rx_buf, bits, words);
454
455 /* write tx fifo */
456 if (tx_buf)
457 tx_fifo(p, tx_buf, words, fifo_shift);
458
459 /* setup clock and rx/tx signals */
460 ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TSCKE);
461 if (rx_buf)
462 ret = ret ? ret : sh_msiof_modify_ctr_wait(p, 0, CTR_RXE);
463 ret = ret ? ret : sh_msiof_modify_ctr_wait(p, 0, CTR_TXE);
464
465 /* start by setting frame bit */
466 INIT_COMPLETION(p->done);
467 ret = ret ? ret : sh_msiof_modify_ctr_wait(p, 0, CTR_TFSE);
468 if (ret) {
469 dev_err(&p->pdev->dev, "failed to start hardware\n");
470 goto err;
471 }
472
473 /* wait for tx fifo to be emptied / rx fifo to be filled */
474 wait_for_completion(&p->done);
475
476 /* read rx fifo */
477 if (rx_buf)
478 rx_fifo(p, rx_buf, words, fifo_shift);
479
480 /* clear status bits */
481 sh_msiof_reset_str(p);
482
483 /* shut down frame, tx/tx and clock signals */
484 ret = sh_msiof_modify_ctr_wait(p, CTR_TFSE, 0);
485 ret = ret ? ret : sh_msiof_modify_ctr_wait(p, CTR_TXE, 0);
486 if (rx_buf)
487 ret = ret ? ret : sh_msiof_modify_ctr_wait(p, CTR_RXE, 0);
488 ret = ret ? ret : sh_msiof_modify_ctr_wait(p, CTR_TSCKE, 0);
489 if (ret) {
490 dev_err(&p->pdev->dev, "failed to shut down hardware\n");
491 goto err;
492 }
493
494 return words;
495
496 err:
497 sh_msiof_write(p, IER, 0);
498 return ret;
499}
500
501static int sh_msiof_spi_txrx(struct spi_device *spi, struct spi_transfer *t)
502{
503 struct sh_msiof_spi_priv *p = spi_master_get_devdata(spi->master);
504 void (*tx_fifo)(struct sh_msiof_spi_priv *, const void *, int, int);
505 void (*rx_fifo)(struct sh_msiof_spi_priv *, void *, int, int);
506 int bits;
507 int bytes_per_word;
508 int bytes_done;
509 int words;
510 int n;
511 bool swab;
512
513 bits = sh_msiof_spi_bits(spi, t);
514
515 if (bits <= 8 && t->len > 15 && !(t->len & 3)) {
516 bits = 32;
517 swab = true;
518 } else {
519 swab = false;
520 }
521
522 /* setup bytes per word and fifo read/write functions */
523 if (bits <= 8) {
524 bytes_per_word = 1;
525 tx_fifo = sh_msiof_spi_write_fifo_8;
526 rx_fifo = sh_msiof_spi_read_fifo_8;
527 } else if (bits <= 16) {
528 bytes_per_word = 2;
529 if ((unsigned long)t->tx_buf & 0x01)
530 tx_fifo = sh_msiof_spi_write_fifo_16u;
531 else
532 tx_fifo = sh_msiof_spi_write_fifo_16;
533
534 if ((unsigned long)t->rx_buf & 0x01)
535 rx_fifo = sh_msiof_spi_read_fifo_16u;
536 else
537 rx_fifo = sh_msiof_spi_read_fifo_16;
538 } else if (swab) {
539 bytes_per_word = 4;
540 if ((unsigned long)t->tx_buf & 0x03)
541 tx_fifo = sh_msiof_spi_write_fifo_s32u;
542 else
543 tx_fifo = sh_msiof_spi_write_fifo_s32;
544
545 if ((unsigned long)t->rx_buf & 0x03)
546 rx_fifo = sh_msiof_spi_read_fifo_s32u;
547 else
548 rx_fifo = sh_msiof_spi_read_fifo_s32;
549 } else {
550 bytes_per_word = 4;
551 if ((unsigned long)t->tx_buf & 0x03)
552 tx_fifo = sh_msiof_spi_write_fifo_32u;
553 else
554 tx_fifo = sh_msiof_spi_write_fifo_32;
555
556 if ((unsigned long)t->rx_buf & 0x03)
557 rx_fifo = sh_msiof_spi_read_fifo_32u;
558 else
559 rx_fifo = sh_msiof_spi_read_fifo_32;
560 }
561
562 /* setup clocks (clock already enabled in chipselect()) */
563 sh_msiof_spi_set_clk_regs(p, clk_get_rate(p->clk),
564 sh_msiof_spi_hz(spi, t));
565
566 /* transfer in fifo sized chunks */
567 words = t->len / bytes_per_word;
568 bytes_done = 0;
569
570 while (bytes_done < t->len) {
571 void *rx_buf = t->rx_buf ? t->rx_buf + bytes_done : NULL;
572 const void *tx_buf = t->tx_buf ? t->tx_buf + bytes_done : NULL;
573 n = sh_msiof_spi_txrx_once(p, tx_fifo, rx_fifo,
574 tx_buf,
575 rx_buf,
576 words, bits);
577 if (n < 0)
578 break;
579
580 bytes_done += n * bytes_per_word;
581 words -= n;
582 }
583
584 return bytes_done;
585}
586
587static u32 sh_msiof_spi_txrx_word(struct spi_device *spi, unsigned nsecs,
588 u32 word, u8 bits)
589{
590 BUG(); /* unused but needed by bitbang code */
591 return 0;
592}
593
594static int sh_msiof_spi_probe(struct platform_device *pdev)
595{
596 struct resource *r;
597 struct spi_master *master;
598 struct sh_msiof_spi_priv *p;
599 char clk_name[16];
600 int i;
601 int ret;
602
603 master = spi_alloc_master(&pdev->dev, sizeof(struct sh_msiof_spi_priv));
604 if (master == NULL) {
605 dev_err(&pdev->dev, "failed to allocate spi master\n");
606 ret = -ENOMEM;
607 goto err0;
608 }
609
610 p = spi_master_get_devdata(master);
611
612 platform_set_drvdata(pdev, p);
613 p->info = pdev->dev.platform_data;
614 init_completion(&p->done);
615
616 snprintf(clk_name, sizeof(clk_name), "msiof%d", pdev->id);
617 p->clk = clk_get(&pdev->dev, clk_name);
618 if (IS_ERR(p->clk)) {
619 dev_err(&pdev->dev, "cannot get clock \"%s\"\n", clk_name);
620 ret = PTR_ERR(p->clk);
621 goto err1;
622 }
623
624 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
625 i = platform_get_irq(pdev, 0);
626 if (!r || i < 0) {
627 dev_err(&pdev->dev, "cannot get platform resources\n");
628 ret = -ENOENT;
629 goto err2;
630 }
631 p->mapbase = ioremap_nocache(r->start, resource_size(r));
632 if (!p->mapbase) {
633 dev_err(&pdev->dev, "unable to ioremap\n");
634 ret = -ENXIO;
635 goto err2;
636 }
637
638 ret = request_irq(i, sh_msiof_spi_irq, IRQF_DISABLED,
639 dev_name(&pdev->dev), p);
640 if (ret) {
641 dev_err(&pdev->dev, "unable to request irq\n");
642 goto err3;
643 }
644
645 p->pdev = pdev;
646 pm_runtime_enable(&pdev->dev);
647
648 /* The standard version of MSIOF use 64 word FIFOs */
649 p->tx_fifo_size = 64;
650 p->rx_fifo_size = 64;
651
652 /* Platform data may override FIFO sizes */
653 if (p->info->tx_fifo_override)
654 p->tx_fifo_size = p->info->tx_fifo_override;
655 if (p->info->rx_fifo_override)
656 p->rx_fifo_size = p->info->rx_fifo_override;
657
658 /* init master and bitbang code */
659 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
660 master->mode_bits |= SPI_LSB_FIRST | SPI_3WIRE;
661 master->flags = 0;
662 master->bus_num = pdev->id;
663 master->num_chipselect = p->info->num_chipselect;
664 master->setup = spi_bitbang_setup;
665 master->cleanup = spi_bitbang_cleanup;
666
667 p->bitbang.master = master;
668 p->bitbang.chipselect = sh_msiof_spi_chipselect;
669 p->bitbang.setup_transfer = sh_msiof_spi_setup_transfer;
670 p->bitbang.txrx_bufs = sh_msiof_spi_txrx;
671 p->bitbang.txrx_word[SPI_MODE_0] = sh_msiof_spi_txrx_word;
672 p->bitbang.txrx_word[SPI_MODE_1] = sh_msiof_spi_txrx_word;
673 p->bitbang.txrx_word[SPI_MODE_2] = sh_msiof_spi_txrx_word;
674 p->bitbang.txrx_word[SPI_MODE_3] = sh_msiof_spi_txrx_word;
675
676 ret = spi_bitbang_start(&p->bitbang);
677 if (ret == 0)
678 return 0;
679
680 pm_runtime_disable(&pdev->dev);
681 err3:
682 iounmap(p->mapbase);
683 err2:
684 clk_put(p->clk);
685 err1:
686 spi_master_put(master);
687 err0:
688 return ret;
689}
690
691static int sh_msiof_spi_remove(struct platform_device *pdev)
692{
693 struct sh_msiof_spi_priv *p = platform_get_drvdata(pdev);
694 int ret;
695
696 ret = spi_bitbang_stop(&p->bitbang);
697 if (!ret) {
698 pm_runtime_disable(&pdev->dev);
699 free_irq(platform_get_irq(pdev, 0), p);
700 iounmap(p->mapbase);
701 clk_put(p->clk);
702 spi_master_put(p->bitbang.master);
703 }
704 return ret;
705}
706
707static int sh_msiof_spi_runtime_nop(struct device *dev)
708{
709 /* Runtime PM callback shared between ->runtime_suspend()
710 * and ->runtime_resume(). Simply returns success.
711 *
712 * This driver re-initializes all registers after
713 * pm_runtime_get_sync() anyway so there is no need
714 * to save and restore registers here.
715 */
716 return 0;
717}
718
719static struct dev_pm_ops sh_msiof_spi_dev_pm_ops = {
720 .runtime_suspend = sh_msiof_spi_runtime_nop,
721 .runtime_resume = sh_msiof_spi_runtime_nop,
722};
723
724static struct platform_driver sh_msiof_spi_drv = {
725 .probe = sh_msiof_spi_probe,
726 .remove = sh_msiof_spi_remove,
727 .driver = {
728 .name = "spi_sh_msiof",
729 .owner = THIS_MODULE,
730 .pm = &sh_msiof_spi_dev_pm_ops,
731 },
732};
733
734static int __init sh_msiof_spi_init(void)
735{
736 return platform_driver_register(&sh_msiof_spi_drv);
737}
738module_init(sh_msiof_spi_init);
739
740static void __exit sh_msiof_spi_exit(void)
741{
742 platform_driver_unregister(&sh_msiof_spi_drv);
743}
744module_exit(sh_msiof_spi_exit);
745
746MODULE_DESCRIPTION("SuperH MSIOF SPI Master Interface Driver");
747MODULE_AUTHOR("Magnus Damm");
748MODULE_LICENSE("GPL v2");
749MODULE_ALIAS("platform:spi_sh_msiof");
1/*
2 * SuperH MSIOF SPI Master Interface
3 *
4 * Copyright (c) 2009 Magnus Damm
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 */
11
12#include <linux/bitmap.h>
13#include <linux/clk.h>
14#include <linux/completion.h>
15#include <linux/delay.h>
16#include <linux/err.h>
17#include <linux/gpio.h>
18#include <linux/init.h>
19#include <linux/interrupt.h>
20#include <linux/io.h>
21#include <linux/kernel.h>
22#include <linux/module.h>
23#include <linux/platform_device.h>
24#include <linux/pm_runtime.h>
25
26#include <linux/spi/sh_msiof.h>
27#include <linux/spi/spi.h>
28#include <linux/spi/spi_bitbang.h>
29
30#include <asm/unaligned.h>
31
32struct sh_msiof_spi_priv {
33 struct spi_bitbang bitbang; /* must be first for spi_bitbang.c */
34 void __iomem *mapbase;
35 struct clk *clk;
36 struct platform_device *pdev;
37 struct sh_msiof_spi_info *info;
38 struct completion done;
39 unsigned long flags;
40 int tx_fifo_size;
41 int rx_fifo_size;
42};
43
44#define TMDR1 0x00
45#define TMDR2 0x04
46#define TMDR3 0x08
47#define RMDR1 0x10
48#define RMDR2 0x14
49#define RMDR3 0x18
50#define TSCR 0x20
51#define RSCR 0x22
52#define CTR 0x28
53#define FCTR 0x30
54#define STR 0x40
55#define IER 0x44
56#define TDR1 0x48
57#define TDR2 0x4c
58#define TFDR 0x50
59#define RDR1 0x58
60#define RDR2 0x5c
61#define RFDR 0x60
62
63#define CTR_TSCKE (1 << 15)
64#define CTR_TFSE (1 << 14)
65#define CTR_TXE (1 << 9)
66#define CTR_RXE (1 << 8)
67
68#define STR_TEOF (1 << 23)
69#define STR_REOF (1 << 7)
70
71static u32 sh_msiof_read(struct sh_msiof_spi_priv *p, int reg_offs)
72{
73 switch (reg_offs) {
74 case TSCR:
75 case RSCR:
76 return ioread16(p->mapbase + reg_offs);
77 default:
78 return ioread32(p->mapbase + reg_offs);
79 }
80}
81
82static void sh_msiof_write(struct sh_msiof_spi_priv *p, int reg_offs,
83 u32 value)
84{
85 switch (reg_offs) {
86 case TSCR:
87 case RSCR:
88 iowrite16(value, p->mapbase + reg_offs);
89 break;
90 default:
91 iowrite32(value, p->mapbase + reg_offs);
92 break;
93 }
94}
95
96static int sh_msiof_modify_ctr_wait(struct sh_msiof_spi_priv *p,
97 u32 clr, u32 set)
98{
99 u32 mask = clr | set;
100 u32 data;
101 int k;
102
103 data = sh_msiof_read(p, CTR);
104 data &= ~clr;
105 data |= set;
106 sh_msiof_write(p, CTR, data);
107
108 for (k = 100; k > 0; k--) {
109 if ((sh_msiof_read(p, CTR) & mask) == set)
110 break;
111
112 udelay(10);
113 }
114
115 return k > 0 ? 0 : -ETIMEDOUT;
116}
117
118static irqreturn_t sh_msiof_spi_irq(int irq, void *data)
119{
120 struct sh_msiof_spi_priv *p = data;
121
122 /* just disable the interrupt and wake up */
123 sh_msiof_write(p, IER, 0);
124 complete(&p->done);
125
126 return IRQ_HANDLED;
127}
128
129static struct {
130 unsigned short div;
131 unsigned short scr;
132} const sh_msiof_spi_clk_table[] = {
133 { 1, 0x0007 },
134 { 2, 0x0000 },
135 { 4, 0x0001 },
136 { 8, 0x0002 },
137 { 16, 0x0003 },
138 { 32, 0x0004 },
139 { 64, 0x1f00 },
140 { 128, 0x1f01 },
141 { 256, 0x1f02 },
142 { 512, 0x1f03 },
143 { 1024, 0x1f04 },
144};
145
146static void sh_msiof_spi_set_clk_regs(struct sh_msiof_spi_priv *p,
147 unsigned long parent_rate,
148 unsigned long spi_hz)
149{
150 unsigned long div = 1024;
151 size_t k;
152
153 if (!WARN_ON(!spi_hz || !parent_rate))
154 div = parent_rate / spi_hz;
155
156 /* TODO: make more fine grained */
157
158 for (k = 0; k < ARRAY_SIZE(sh_msiof_spi_clk_table); k++) {
159 if (sh_msiof_spi_clk_table[k].div >= div)
160 break;
161 }
162
163 k = min_t(int, k, ARRAY_SIZE(sh_msiof_spi_clk_table) - 1);
164
165 sh_msiof_write(p, TSCR, sh_msiof_spi_clk_table[k].scr);
166 sh_msiof_write(p, RSCR, sh_msiof_spi_clk_table[k].scr);
167}
168
169static void sh_msiof_spi_set_pin_regs(struct sh_msiof_spi_priv *p,
170 u32 cpol, u32 cpha,
171 u32 tx_hi_z, u32 lsb_first)
172{
173 u32 tmp;
174 int edge;
175
176 /*
177 * CPOL CPHA TSCKIZ RSCKIZ TEDG REDG
178 * 0 0 10 10 1 1
179 * 0 1 10 10 0 0
180 * 1 0 11 11 0 0
181 * 1 1 11 11 1 1
182 */
183 sh_msiof_write(p, FCTR, 0);
184 sh_msiof_write(p, TMDR1, 0xe2000005 | (lsb_first << 24));
185 sh_msiof_write(p, RMDR1, 0x22000005 | (lsb_first << 24));
186
187 tmp = 0xa0000000;
188 tmp |= cpol << 30; /* TSCKIZ */
189 tmp |= cpol << 28; /* RSCKIZ */
190
191 edge = cpol ^ !cpha;
192
193 tmp |= edge << 27; /* TEDG */
194 tmp |= edge << 26; /* REDG */
195 tmp |= (tx_hi_z ? 2 : 0) << 22; /* TXDIZ */
196 sh_msiof_write(p, CTR, tmp);
197}
198
199static void sh_msiof_spi_set_mode_regs(struct sh_msiof_spi_priv *p,
200 const void *tx_buf, void *rx_buf,
201 u32 bits, u32 words)
202{
203 u32 dr2 = ((bits - 1) << 24) | ((words - 1) << 16);
204
205 if (tx_buf)
206 sh_msiof_write(p, TMDR2, dr2);
207 else
208 sh_msiof_write(p, TMDR2, dr2 | 1);
209
210 if (rx_buf)
211 sh_msiof_write(p, RMDR2, dr2);
212
213 sh_msiof_write(p, IER, STR_TEOF | STR_REOF);
214}
215
216static void sh_msiof_reset_str(struct sh_msiof_spi_priv *p)
217{
218 sh_msiof_write(p, STR, sh_msiof_read(p, STR));
219}
220
221static void sh_msiof_spi_write_fifo_8(struct sh_msiof_spi_priv *p,
222 const void *tx_buf, int words, int fs)
223{
224 const u8 *buf_8 = tx_buf;
225 int k;
226
227 for (k = 0; k < words; k++)
228 sh_msiof_write(p, TFDR, buf_8[k] << fs);
229}
230
231static void sh_msiof_spi_write_fifo_16(struct sh_msiof_spi_priv *p,
232 const void *tx_buf, int words, int fs)
233{
234 const u16 *buf_16 = tx_buf;
235 int k;
236
237 for (k = 0; k < words; k++)
238 sh_msiof_write(p, TFDR, buf_16[k] << fs);
239}
240
241static void sh_msiof_spi_write_fifo_16u(struct sh_msiof_spi_priv *p,
242 const void *tx_buf, int words, int fs)
243{
244 const u16 *buf_16 = tx_buf;
245 int k;
246
247 for (k = 0; k < words; k++)
248 sh_msiof_write(p, TFDR, get_unaligned(&buf_16[k]) << fs);
249}
250
251static void sh_msiof_spi_write_fifo_32(struct sh_msiof_spi_priv *p,
252 const void *tx_buf, int words, int fs)
253{
254 const u32 *buf_32 = tx_buf;
255 int k;
256
257 for (k = 0; k < words; k++)
258 sh_msiof_write(p, TFDR, buf_32[k] << fs);
259}
260
261static void sh_msiof_spi_write_fifo_32u(struct sh_msiof_spi_priv *p,
262 const void *tx_buf, int words, int fs)
263{
264 const u32 *buf_32 = tx_buf;
265 int k;
266
267 for (k = 0; k < words; k++)
268 sh_msiof_write(p, TFDR, get_unaligned(&buf_32[k]) << fs);
269}
270
271static void sh_msiof_spi_write_fifo_s32(struct sh_msiof_spi_priv *p,
272 const void *tx_buf, int words, int fs)
273{
274 const u32 *buf_32 = tx_buf;
275 int k;
276
277 for (k = 0; k < words; k++)
278 sh_msiof_write(p, TFDR, swab32(buf_32[k] << fs));
279}
280
281static void sh_msiof_spi_write_fifo_s32u(struct sh_msiof_spi_priv *p,
282 const void *tx_buf, int words, int fs)
283{
284 const u32 *buf_32 = tx_buf;
285 int k;
286
287 for (k = 0; k < words; k++)
288 sh_msiof_write(p, TFDR, swab32(get_unaligned(&buf_32[k]) << fs));
289}
290
291static void sh_msiof_spi_read_fifo_8(struct sh_msiof_spi_priv *p,
292 void *rx_buf, int words, int fs)
293{
294 u8 *buf_8 = rx_buf;
295 int k;
296
297 for (k = 0; k < words; k++)
298 buf_8[k] = sh_msiof_read(p, RFDR) >> fs;
299}
300
301static void sh_msiof_spi_read_fifo_16(struct sh_msiof_spi_priv *p,
302 void *rx_buf, int words, int fs)
303{
304 u16 *buf_16 = rx_buf;
305 int k;
306
307 for (k = 0; k < words; k++)
308 buf_16[k] = sh_msiof_read(p, RFDR) >> fs;
309}
310
311static void sh_msiof_spi_read_fifo_16u(struct sh_msiof_spi_priv *p,
312 void *rx_buf, int words, int fs)
313{
314 u16 *buf_16 = rx_buf;
315 int k;
316
317 for (k = 0; k < words; k++)
318 put_unaligned(sh_msiof_read(p, RFDR) >> fs, &buf_16[k]);
319}
320
321static void sh_msiof_spi_read_fifo_32(struct sh_msiof_spi_priv *p,
322 void *rx_buf, int words, int fs)
323{
324 u32 *buf_32 = rx_buf;
325 int k;
326
327 for (k = 0; k < words; k++)
328 buf_32[k] = sh_msiof_read(p, RFDR) >> fs;
329}
330
331static void sh_msiof_spi_read_fifo_32u(struct sh_msiof_spi_priv *p,
332 void *rx_buf, int words, int fs)
333{
334 u32 *buf_32 = rx_buf;
335 int k;
336
337 for (k = 0; k < words; k++)
338 put_unaligned(sh_msiof_read(p, RFDR) >> fs, &buf_32[k]);
339}
340
341static void sh_msiof_spi_read_fifo_s32(struct sh_msiof_spi_priv *p,
342 void *rx_buf, int words, int fs)
343{
344 u32 *buf_32 = rx_buf;
345 int k;
346
347 for (k = 0; k < words; k++)
348 buf_32[k] = swab32(sh_msiof_read(p, RFDR) >> fs);
349}
350
351static void sh_msiof_spi_read_fifo_s32u(struct sh_msiof_spi_priv *p,
352 void *rx_buf, int words, int fs)
353{
354 u32 *buf_32 = rx_buf;
355 int k;
356
357 for (k = 0; k < words; k++)
358 put_unaligned(swab32(sh_msiof_read(p, RFDR) >> fs), &buf_32[k]);
359}
360
361static int sh_msiof_spi_bits(struct spi_device *spi, struct spi_transfer *t)
362{
363 int bits;
364
365 bits = t ? t->bits_per_word : 0;
366 if (!bits)
367 bits = spi->bits_per_word;
368 return bits;
369}
370
371static unsigned long sh_msiof_spi_hz(struct spi_device *spi,
372 struct spi_transfer *t)
373{
374 unsigned long hz;
375
376 hz = t ? t->speed_hz : 0;
377 if (!hz)
378 hz = spi->max_speed_hz;
379 return hz;
380}
381
382static int sh_msiof_spi_setup_transfer(struct spi_device *spi,
383 struct spi_transfer *t)
384{
385 int bits;
386
387 /* noting to check hz values against since parent clock is disabled */
388
389 bits = sh_msiof_spi_bits(spi, t);
390 if (bits < 8)
391 return -EINVAL;
392 if (bits > 32)
393 return -EINVAL;
394
395 return spi_bitbang_setup_transfer(spi, t);
396}
397
398static void sh_msiof_spi_chipselect(struct spi_device *spi, int is_on)
399{
400 struct sh_msiof_spi_priv *p = spi_master_get_devdata(spi->master);
401 int value;
402
403 /* chip select is active low unless SPI_CS_HIGH is set */
404 if (spi->mode & SPI_CS_HIGH)
405 value = (is_on == BITBANG_CS_ACTIVE) ? 1 : 0;
406 else
407 value = (is_on == BITBANG_CS_ACTIVE) ? 0 : 1;
408
409 if (is_on == BITBANG_CS_ACTIVE) {
410 if (!test_and_set_bit(0, &p->flags)) {
411 pm_runtime_get_sync(&p->pdev->dev);
412 clk_enable(p->clk);
413 }
414
415 /* Configure pins before asserting CS */
416 sh_msiof_spi_set_pin_regs(p, !!(spi->mode & SPI_CPOL),
417 !!(spi->mode & SPI_CPHA),
418 !!(spi->mode & SPI_3WIRE),
419 !!(spi->mode & SPI_LSB_FIRST));
420 }
421
422 /* use spi->controller data for CS (same strategy as spi_gpio) */
423 gpio_set_value((unsigned)spi->controller_data, value);
424
425 if (is_on == BITBANG_CS_INACTIVE) {
426 if (test_and_clear_bit(0, &p->flags)) {
427 clk_disable(p->clk);
428 pm_runtime_put(&p->pdev->dev);
429 }
430 }
431}
432
433static int sh_msiof_spi_txrx_once(struct sh_msiof_spi_priv *p,
434 void (*tx_fifo)(struct sh_msiof_spi_priv *,
435 const void *, int, int),
436 void (*rx_fifo)(struct sh_msiof_spi_priv *,
437 void *, int, int),
438 const void *tx_buf, void *rx_buf,
439 int words, int bits)
440{
441 int fifo_shift;
442 int ret;
443
444 /* limit maximum word transfer to rx/tx fifo size */
445 if (tx_buf)
446 words = min_t(int, words, p->tx_fifo_size);
447 if (rx_buf)
448 words = min_t(int, words, p->rx_fifo_size);
449
450 /* the fifo contents need shifting */
451 fifo_shift = 32 - bits;
452
453 /* setup msiof transfer mode registers */
454 sh_msiof_spi_set_mode_regs(p, tx_buf, rx_buf, bits, words);
455
456 /* write tx fifo */
457 if (tx_buf)
458 tx_fifo(p, tx_buf, words, fifo_shift);
459
460 /* setup clock and rx/tx signals */
461 ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TSCKE);
462 if (rx_buf)
463 ret = ret ? ret : sh_msiof_modify_ctr_wait(p, 0, CTR_RXE);
464 ret = ret ? ret : sh_msiof_modify_ctr_wait(p, 0, CTR_TXE);
465
466 /* start by setting frame bit */
467 INIT_COMPLETION(p->done);
468 ret = ret ? ret : sh_msiof_modify_ctr_wait(p, 0, CTR_TFSE);
469 if (ret) {
470 dev_err(&p->pdev->dev, "failed to start hardware\n");
471 goto err;
472 }
473
474 /* wait for tx fifo to be emptied / rx fifo to be filled */
475 wait_for_completion(&p->done);
476
477 /* read rx fifo */
478 if (rx_buf)
479 rx_fifo(p, rx_buf, words, fifo_shift);
480
481 /* clear status bits */
482 sh_msiof_reset_str(p);
483
484 /* shut down frame, tx/tx and clock signals */
485 ret = sh_msiof_modify_ctr_wait(p, CTR_TFSE, 0);
486 ret = ret ? ret : sh_msiof_modify_ctr_wait(p, CTR_TXE, 0);
487 if (rx_buf)
488 ret = ret ? ret : sh_msiof_modify_ctr_wait(p, CTR_RXE, 0);
489 ret = ret ? ret : sh_msiof_modify_ctr_wait(p, CTR_TSCKE, 0);
490 if (ret) {
491 dev_err(&p->pdev->dev, "failed to shut down hardware\n");
492 goto err;
493 }
494
495 return words;
496
497 err:
498 sh_msiof_write(p, IER, 0);
499 return ret;
500}
501
502static int sh_msiof_spi_txrx(struct spi_device *spi, struct spi_transfer *t)
503{
504 struct sh_msiof_spi_priv *p = spi_master_get_devdata(spi->master);
505 void (*tx_fifo)(struct sh_msiof_spi_priv *, const void *, int, int);
506 void (*rx_fifo)(struct sh_msiof_spi_priv *, void *, int, int);
507 int bits;
508 int bytes_per_word;
509 int bytes_done;
510 int words;
511 int n;
512 bool swab;
513
514 bits = sh_msiof_spi_bits(spi, t);
515
516 if (bits <= 8 && t->len > 15 && !(t->len & 3)) {
517 bits = 32;
518 swab = true;
519 } else {
520 swab = false;
521 }
522
523 /* setup bytes per word and fifo read/write functions */
524 if (bits <= 8) {
525 bytes_per_word = 1;
526 tx_fifo = sh_msiof_spi_write_fifo_8;
527 rx_fifo = sh_msiof_spi_read_fifo_8;
528 } else if (bits <= 16) {
529 bytes_per_word = 2;
530 if ((unsigned long)t->tx_buf & 0x01)
531 tx_fifo = sh_msiof_spi_write_fifo_16u;
532 else
533 tx_fifo = sh_msiof_spi_write_fifo_16;
534
535 if ((unsigned long)t->rx_buf & 0x01)
536 rx_fifo = sh_msiof_spi_read_fifo_16u;
537 else
538 rx_fifo = sh_msiof_spi_read_fifo_16;
539 } else if (swab) {
540 bytes_per_word = 4;
541 if ((unsigned long)t->tx_buf & 0x03)
542 tx_fifo = sh_msiof_spi_write_fifo_s32u;
543 else
544 tx_fifo = sh_msiof_spi_write_fifo_s32;
545
546 if ((unsigned long)t->rx_buf & 0x03)
547 rx_fifo = sh_msiof_spi_read_fifo_s32u;
548 else
549 rx_fifo = sh_msiof_spi_read_fifo_s32;
550 } else {
551 bytes_per_word = 4;
552 if ((unsigned long)t->tx_buf & 0x03)
553 tx_fifo = sh_msiof_spi_write_fifo_32u;
554 else
555 tx_fifo = sh_msiof_spi_write_fifo_32;
556
557 if ((unsigned long)t->rx_buf & 0x03)
558 rx_fifo = sh_msiof_spi_read_fifo_32u;
559 else
560 rx_fifo = sh_msiof_spi_read_fifo_32;
561 }
562
563 /* setup clocks (clock already enabled in chipselect()) */
564 sh_msiof_spi_set_clk_regs(p, clk_get_rate(p->clk),
565 sh_msiof_spi_hz(spi, t));
566
567 /* transfer in fifo sized chunks */
568 words = t->len / bytes_per_word;
569 bytes_done = 0;
570
571 while (bytes_done < t->len) {
572 void *rx_buf = t->rx_buf ? t->rx_buf + bytes_done : NULL;
573 const void *tx_buf = t->tx_buf ? t->tx_buf + bytes_done : NULL;
574 n = sh_msiof_spi_txrx_once(p, tx_fifo, rx_fifo,
575 tx_buf,
576 rx_buf,
577 words, bits);
578 if (n < 0)
579 break;
580
581 bytes_done += n * bytes_per_word;
582 words -= n;
583 }
584
585 return bytes_done;
586}
587
588static u32 sh_msiof_spi_txrx_word(struct spi_device *spi, unsigned nsecs,
589 u32 word, u8 bits)
590{
591 BUG(); /* unused but needed by bitbang code */
592 return 0;
593}
594
595static int sh_msiof_spi_probe(struct platform_device *pdev)
596{
597 struct resource *r;
598 struct spi_master *master;
599 struct sh_msiof_spi_priv *p;
600 char clk_name[16];
601 int i;
602 int ret;
603
604 master = spi_alloc_master(&pdev->dev, sizeof(struct sh_msiof_spi_priv));
605 if (master == NULL) {
606 dev_err(&pdev->dev, "failed to allocate spi master\n");
607 ret = -ENOMEM;
608 goto err0;
609 }
610
611 p = spi_master_get_devdata(master);
612
613 platform_set_drvdata(pdev, p);
614 p->info = pdev->dev.platform_data;
615 init_completion(&p->done);
616
617 snprintf(clk_name, sizeof(clk_name), "msiof%d", pdev->id);
618 p->clk = clk_get(&pdev->dev, clk_name);
619 if (IS_ERR(p->clk)) {
620 dev_err(&pdev->dev, "cannot get clock \"%s\"\n", clk_name);
621 ret = PTR_ERR(p->clk);
622 goto err1;
623 }
624
625 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
626 i = platform_get_irq(pdev, 0);
627 if (!r || i < 0) {
628 dev_err(&pdev->dev, "cannot get platform resources\n");
629 ret = -ENOENT;
630 goto err2;
631 }
632 p->mapbase = ioremap_nocache(r->start, resource_size(r));
633 if (!p->mapbase) {
634 dev_err(&pdev->dev, "unable to ioremap\n");
635 ret = -ENXIO;
636 goto err2;
637 }
638
639 ret = request_irq(i, sh_msiof_spi_irq, 0,
640 dev_name(&pdev->dev), p);
641 if (ret) {
642 dev_err(&pdev->dev, "unable to request irq\n");
643 goto err3;
644 }
645
646 p->pdev = pdev;
647 pm_runtime_enable(&pdev->dev);
648
649 /* The standard version of MSIOF use 64 word FIFOs */
650 p->tx_fifo_size = 64;
651 p->rx_fifo_size = 64;
652
653 /* Platform data may override FIFO sizes */
654 if (p->info->tx_fifo_override)
655 p->tx_fifo_size = p->info->tx_fifo_override;
656 if (p->info->rx_fifo_override)
657 p->rx_fifo_size = p->info->rx_fifo_override;
658
659 /* init master and bitbang code */
660 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
661 master->mode_bits |= SPI_LSB_FIRST | SPI_3WIRE;
662 master->flags = 0;
663 master->bus_num = pdev->id;
664 master->num_chipselect = p->info->num_chipselect;
665 master->setup = spi_bitbang_setup;
666 master->cleanup = spi_bitbang_cleanup;
667
668 p->bitbang.master = master;
669 p->bitbang.chipselect = sh_msiof_spi_chipselect;
670 p->bitbang.setup_transfer = sh_msiof_spi_setup_transfer;
671 p->bitbang.txrx_bufs = sh_msiof_spi_txrx;
672 p->bitbang.txrx_word[SPI_MODE_0] = sh_msiof_spi_txrx_word;
673 p->bitbang.txrx_word[SPI_MODE_1] = sh_msiof_spi_txrx_word;
674 p->bitbang.txrx_word[SPI_MODE_2] = sh_msiof_spi_txrx_word;
675 p->bitbang.txrx_word[SPI_MODE_3] = sh_msiof_spi_txrx_word;
676
677 ret = spi_bitbang_start(&p->bitbang);
678 if (ret == 0)
679 return 0;
680
681 pm_runtime_disable(&pdev->dev);
682 err3:
683 iounmap(p->mapbase);
684 err2:
685 clk_put(p->clk);
686 err1:
687 spi_master_put(master);
688 err0:
689 return ret;
690}
691
692static int sh_msiof_spi_remove(struct platform_device *pdev)
693{
694 struct sh_msiof_spi_priv *p = platform_get_drvdata(pdev);
695 int ret;
696
697 ret = spi_bitbang_stop(&p->bitbang);
698 if (!ret) {
699 pm_runtime_disable(&pdev->dev);
700 free_irq(platform_get_irq(pdev, 0), p);
701 iounmap(p->mapbase);
702 clk_put(p->clk);
703 spi_master_put(p->bitbang.master);
704 }
705 return ret;
706}
707
708static int sh_msiof_spi_runtime_nop(struct device *dev)
709{
710 /* Runtime PM callback shared between ->runtime_suspend()
711 * and ->runtime_resume(). Simply returns success.
712 *
713 * This driver re-initializes all registers after
714 * pm_runtime_get_sync() anyway so there is no need
715 * to save and restore registers here.
716 */
717 return 0;
718}
719
720static struct dev_pm_ops sh_msiof_spi_dev_pm_ops = {
721 .runtime_suspend = sh_msiof_spi_runtime_nop,
722 .runtime_resume = sh_msiof_spi_runtime_nop,
723};
724
725static struct platform_driver sh_msiof_spi_drv = {
726 .probe = sh_msiof_spi_probe,
727 .remove = sh_msiof_spi_remove,
728 .driver = {
729 .name = "spi_sh_msiof",
730 .owner = THIS_MODULE,
731 .pm = &sh_msiof_spi_dev_pm_ops,
732 },
733};
734module_platform_driver(sh_msiof_spi_drv);
735
736MODULE_DESCRIPTION("SuperH MSIOF SPI Master Interface Driver");
737MODULE_AUTHOR("Magnus Damm");
738MODULE_LICENSE("GPL v2");
739MODULE_ALIAS("platform:spi_sh_msiof");