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v3.1
  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");
v4.10.11
   1/*
   2 * SuperH MSIOF SPI Master Interface
   3 *
   4 * Copyright (c) 2009 Magnus Damm
   5 * Copyright (C) 2014 Glider bvba
   6 *
   7 * This program is free software; you can redistribute it and/or modify
   8 * it under the terms of the GNU General Public License version 2 as
   9 * published by the Free Software Foundation.
  10 *
  11 */
  12
  13#include <linux/bitmap.h>
  14#include <linux/clk.h>
  15#include <linux/completion.h>
  16#include <linux/delay.h>
  17#include <linux/dma-mapping.h>
  18#include <linux/dmaengine.h>
  19#include <linux/err.h>
  20#include <linux/gpio.h>
 
  21#include <linux/interrupt.h>
  22#include <linux/io.h>
  23#include <linux/kernel.h>
  24#include <linux/module.h>
  25#include <linux/of.h>
  26#include <linux/of_device.h>
  27#include <linux/platform_device.h>
  28#include <linux/pm_runtime.h>
  29#include <linux/sh_dma.h>
  30
  31#include <linux/spi/sh_msiof.h>
  32#include <linux/spi/spi.h>
 
  33
  34#include <asm/unaligned.h>
  35
  36
  37struct sh_msiof_chipdata {
  38	u16 tx_fifo_size;
  39	u16 rx_fifo_size;
  40	u16 master_flags;
  41};
  42
  43struct sh_msiof_spi_priv {
  44	struct spi_master *master;
  45	void __iomem *mapbase;
  46	struct clk *clk;
  47	struct platform_device *pdev;
  48	struct sh_msiof_spi_info *info;
  49	struct completion done;
  50	unsigned int tx_fifo_size;
  51	unsigned int rx_fifo_size;
  52	void *tx_dma_page;
  53	void *rx_dma_page;
  54	dma_addr_t tx_dma_addr;
  55	dma_addr_t rx_dma_addr;
  56};
  57
  58#define TMDR1	0x00	/* Transmit Mode Register 1 */
  59#define TMDR2	0x04	/* Transmit Mode Register 2 */
  60#define TMDR3	0x08	/* Transmit Mode Register 3 */
  61#define RMDR1	0x10	/* Receive Mode Register 1 */
  62#define RMDR2	0x14	/* Receive Mode Register 2 */
  63#define RMDR3	0x18	/* Receive Mode Register 3 */
  64#define TSCR	0x20	/* Transmit Clock Select Register */
  65#define RSCR	0x22	/* Receive Clock Select Register (SH, A1, APE6) */
  66#define CTR	0x28	/* Control Register */
  67#define FCTR	0x30	/* FIFO Control Register */
  68#define STR	0x40	/* Status Register */
  69#define IER	0x44	/* Interrupt Enable Register */
  70#define TDR1	0x48	/* Transmit Control Data Register 1 (SH, A1) */
  71#define TDR2	0x4c	/* Transmit Control Data Register 2 (SH, A1) */
  72#define TFDR	0x50	/* Transmit FIFO Data Register */
  73#define RDR1	0x58	/* Receive Control Data Register 1 (SH, A1) */
  74#define RDR2	0x5c	/* Receive Control Data Register 2 (SH, A1) */
  75#define RFDR	0x60	/* Receive FIFO Data Register */
  76
  77/* TMDR1 and RMDR1 */
  78#define MDR1_TRMD	 0x80000000 /* Transfer Mode (1 = Master mode) */
  79#define MDR1_SYNCMD_MASK 0x30000000 /* SYNC Mode */
  80#define MDR1_SYNCMD_SPI	 0x20000000 /*   Level mode/SPI */
  81#define MDR1_SYNCMD_LR	 0x30000000 /*   L/R mode */
  82#define MDR1_SYNCAC_SHIFT	 25 /* Sync Polarity (1 = Active-low) */
  83#define MDR1_BITLSB_SHIFT	 24 /* MSB/LSB First (1 = LSB first) */
  84#define MDR1_DTDL_SHIFT		 20 /* Data Pin Bit Delay for MSIOF_SYNC */
  85#define MDR1_SYNCDL_SHIFT	 16 /* Frame Sync Signal Timing Delay */
  86#define MDR1_FLD_MASK	 0x0000000c /* Frame Sync Signal Interval (0-3) */
  87#define MDR1_FLD_SHIFT		  2
  88#define MDR1_XXSTP	 0x00000001 /* Transmission/Reception Stop on FIFO */
  89/* TMDR1 */
  90#define TMDR1_PCON	 0x40000000 /* Transfer Signal Connection */
  91
  92/* TMDR2 and RMDR2 */
  93#define MDR2_BITLEN1(i)	(((i) - 1) << 24) /* Data Size (8-32 bits) */
  94#define MDR2_WDLEN1(i)	(((i) - 1) << 16) /* Word Count (1-64/256 (SH, A1))) */
  95#define MDR2_GRPMASK1	0x00000001 /* Group Output Mask 1 (SH, A1) */
  96
  97/* TSCR and RSCR */
  98#define SCR_BRPS_MASK	    0x1f00 /* Prescaler Setting (1-32) */
  99#define SCR_BRPS(i)	(((i) - 1) << 8)
 100#define SCR_BRDV_MASK	    0x0007 /* Baud Rate Generator's Division Ratio */
 101#define SCR_BRDV_DIV_2	    0x0000
 102#define SCR_BRDV_DIV_4	    0x0001
 103#define SCR_BRDV_DIV_8	    0x0002
 104#define SCR_BRDV_DIV_16	    0x0003
 105#define SCR_BRDV_DIV_32	    0x0004
 106#define SCR_BRDV_DIV_1	    0x0007
 107
 108/* CTR */
 109#define CTR_TSCKIZ_MASK	0xc0000000 /* Transmit Clock I/O Polarity Select */
 110#define CTR_TSCKIZ_SCK	0x80000000 /*   Disable SCK when TX disabled */
 111#define CTR_TSCKIZ_POL_SHIFT	30 /*   Transmit Clock Polarity */
 112#define CTR_RSCKIZ_MASK	0x30000000 /* Receive Clock Polarity Select */
 113#define CTR_RSCKIZ_SCK	0x20000000 /*   Must match CTR_TSCKIZ_SCK */
 114#define CTR_RSCKIZ_POL_SHIFT	28 /*   Receive Clock Polarity */
 115#define CTR_TEDG_SHIFT		27 /* Transmit Timing (1 = falling edge) */
 116#define CTR_REDG_SHIFT		26 /* Receive Timing (1 = falling edge) */
 117#define CTR_TXDIZ_MASK	0x00c00000 /* Pin Output When TX is Disabled */
 118#define CTR_TXDIZ_LOW	0x00000000 /*   0 */
 119#define CTR_TXDIZ_HIGH	0x00400000 /*   1 */
 120#define CTR_TXDIZ_HIZ	0x00800000 /*   High-impedance */
 121#define CTR_TSCKE	0x00008000 /* Transmit Serial Clock Output Enable */
 122#define CTR_TFSE	0x00004000 /* Transmit Frame Sync Signal Output Enable */
 123#define CTR_TXE		0x00000200 /* Transmit Enable */
 124#define CTR_RXE		0x00000100 /* Receive Enable */
 125
 126/* FCTR */
 127#define FCTR_TFWM_MASK	0xe0000000 /* Transmit FIFO Watermark */
 128#define FCTR_TFWM_64	0x00000000 /*  Transfer Request when 64 empty stages */
 129#define FCTR_TFWM_32	0x20000000 /*  Transfer Request when 32 empty stages */
 130#define FCTR_TFWM_24	0x40000000 /*  Transfer Request when 24 empty stages */
 131#define FCTR_TFWM_16	0x60000000 /*  Transfer Request when 16 empty stages */
 132#define FCTR_TFWM_12	0x80000000 /*  Transfer Request when 12 empty stages */
 133#define FCTR_TFWM_8	0xa0000000 /*  Transfer Request when 8 empty stages */
 134#define FCTR_TFWM_4	0xc0000000 /*  Transfer Request when 4 empty stages */
 135#define FCTR_TFWM_1	0xe0000000 /*  Transfer Request when 1 empty stage */
 136#define FCTR_TFUA_MASK	0x07f00000 /* Transmit FIFO Usable Area */
 137#define FCTR_TFUA_SHIFT		20
 138#define FCTR_TFUA(i)	((i) << FCTR_TFUA_SHIFT)
 139#define FCTR_RFWM_MASK	0x0000e000 /* Receive FIFO Watermark */
 140#define FCTR_RFWM_1	0x00000000 /*  Transfer Request when 1 valid stages */
 141#define FCTR_RFWM_4	0x00002000 /*  Transfer Request when 4 valid stages */
 142#define FCTR_RFWM_8	0x00004000 /*  Transfer Request when 8 valid stages */
 143#define FCTR_RFWM_16	0x00006000 /*  Transfer Request when 16 valid stages */
 144#define FCTR_RFWM_32	0x00008000 /*  Transfer Request when 32 valid stages */
 145#define FCTR_RFWM_64	0x0000a000 /*  Transfer Request when 64 valid stages */
 146#define FCTR_RFWM_128	0x0000c000 /*  Transfer Request when 128 valid stages */
 147#define FCTR_RFWM_256	0x0000e000 /*  Transfer Request when 256 valid stages */
 148#define FCTR_RFUA_MASK	0x00001ff0 /* Receive FIFO Usable Area (0x40 = full) */
 149#define FCTR_RFUA_SHIFT		 4
 150#define FCTR_RFUA(i)	((i) << FCTR_RFUA_SHIFT)
 151
 152/* STR */
 153#define STR_TFEMP	0x20000000 /* Transmit FIFO Empty */
 154#define STR_TDREQ	0x10000000 /* Transmit Data Transfer Request */
 155#define STR_TEOF	0x00800000 /* Frame Transmission End */
 156#define STR_TFSERR	0x00200000 /* Transmit Frame Synchronization Error */
 157#define STR_TFOVF	0x00100000 /* Transmit FIFO Overflow */
 158#define STR_TFUDF	0x00080000 /* Transmit FIFO Underflow */
 159#define STR_RFFUL	0x00002000 /* Receive FIFO Full */
 160#define STR_RDREQ	0x00001000 /* Receive Data Transfer Request */
 161#define STR_REOF	0x00000080 /* Frame Reception End */
 162#define STR_RFSERR	0x00000020 /* Receive Frame Synchronization Error */
 163#define STR_RFUDF	0x00000010 /* Receive FIFO Underflow */
 164#define STR_RFOVF	0x00000008 /* Receive FIFO Overflow */
 165
 166/* IER */
 167#define IER_TDMAE	0x80000000 /* Transmit Data DMA Transfer Req. Enable */
 168#define IER_TFEMPE	0x20000000 /* Transmit FIFO Empty Enable */
 169#define IER_TDREQE	0x10000000 /* Transmit Data Transfer Request Enable */
 170#define IER_TEOFE	0x00800000 /* Frame Transmission End Enable */
 171#define IER_TFSERRE	0x00200000 /* Transmit Frame Sync Error Enable */
 172#define IER_TFOVFE	0x00100000 /* Transmit FIFO Overflow Enable */
 173#define IER_TFUDFE	0x00080000 /* Transmit FIFO Underflow Enable */
 174#define IER_RDMAE	0x00008000 /* Receive Data DMA Transfer Req. Enable */
 175#define IER_RFFULE	0x00002000 /* Receive FIFO Full Enable */
 176#define IER_RDREQE	0x00001000 /* Receive Data Transfer Request Enable */
 177#define IER_REOFE	0x00000080 /* Frame Reception End Enable */
 178#define IER_RFSERRE	0x00000020 /* Receive Frame Sync Error Enable */
 179#define IER_RFUDFE	0x00000010 /* Receive FIFO Underflow Enable */
 180#define IER_RFOVFE	0x00000008 /* Receive FIFO Overflow Enable */
 181
 
 
 182
 183static u32 sh_msiof_read(struct sh_msiof_spi_priv *p, int reg_offs)
 184{
 185	switch (reg_offs) {
 186	case TSCR:
 187	case RSCR:
 188		return ioread16(p->mapbase + reg_offs);
 189	default:
 190		return ioread32(p->mapbase + reg_offs);
 191	}
 192}
 193
 194static void sh_msiof_write(struct sh_msiof_spi_priv *p, int reg_offs,
 195			   u32 value)
 196{
 197	switch (reg_offs) {
 198	case TSCR:
 199	case RSCR:
 200		iowrite16(value, p->mapbase + reg_offs);
 201		break;
 202	default:
 203		iowrite32(value, p->mapbase + reg_offs);
 204		break;
 205	}
 206}
 207
 208static int sh_msiof_modify_ctr_wait(struct sh_msiof_spi_priv *p,
 209				    u32 clr, u32 set)
 210{
 211	u32 mask = clr | set;
 212	u32 data;
 213	int k;
 214
 215	data = sh_msiof_read(p, CTR);
 216	data &= ~clr;
 217	data |= set;
 218	sh_msiof_write(p, CTR, data);
 219
 220	for (k = 100; k > 0; k--) {
 221		if ((sh_msiof_read(p, CTR) & mask) == set)
 222			break;
 223
 224		udelay(10);
 225	}
 226
 227	return k > 0 ? 0 : -ETIMEDOUT;
 228}
 229
 230static irqreturn_t sh_msiof_spi_irq(int irq, void *data)
 231{
 232	struct sh_msiof_spi_priv *p = data;
 233
 234	/* just disable the interrupt and wake up */
 235	sh_msiof_write(p, IER, 0);
 236	complete(&p->done);
 237
 238	return IRQ_HANDLED;
 239}
 240
 241static struct {
 242	unsigned short div;
 243	unsigned short brdv;
 244} const sh_msiof_spi_div_table[] = {
 245	{ 1,	SCR_BRDV_DIV_1 },
 246	{ 2,	SCR_BRDV_DIV_2 },
 247	{ 4,	SCR_BRDV_DIV_4 },
 248	{ 8,	SCR_BRDV_DIV_8 },
 249	{ 16,	SCR_BRDV_DIV_16 },
 250	{ 32,	SCR_BRDV_DIV_32 },
 
 
 
 
 
 251};
 252
 253static void sh_msiof_spi_set_clk_regs(struct sh_msiof_spi_priv *p,
 254				      unsigned long parent_rate, u32 spi_hz)
 
 255{
 256	unsigned long div = 1024;
 257	u32 brps, scr;
 258	size_t k;
 259
 260	if (!WARN_ON(!spi_hz || !parent_rate))
 261		div = DIV_ROUND_UP(parent_rate, spi_hz);
 262
 263	for (k = 0; k < ARRAY_SIZE(sh_msiof_spi_div_table); k++) {
 264		brps = DIV_ROUND_UP(div, sh_msiof_spi_div_table[k].div);
 265		/* SCR_BRDV_DIV_1 is valid only if BRPS is x 1/1 or x 1/2 */
 266		if (sh_msiof_spi_div_table[k].div == 1 && brps > 2)
 267			continue;
 268		if (brps <= 32) /* max of brdv is 32 */
 269			break;
 270	}
 271
 272	k = min_t(int, k, ARRAY_SIZE(sh_msiof_spi_div_table) - 1);
 273
 274	scr = sh_msiof_spi_div_table[k].brdv | SCR_BRPS(brps);
 275	sh_msiof_write(p, TSCR, scr);
 276	if (!(p->master->flags & SPI_MASTER_MUST_TX))
 277		sh_msiof_write(p, RSCR, scr);
 278}
 279
 280static u32 sh_msiof_get_delay_bit(u32 dtdl_or_syncdl)
 281{
 282	/*
 283	 * DTDL/SYNCDL bit	: p->info->dtdl or p->info->syncdl
 284	 * b'000		: 0
 285	 * b'001		: 100
 286	 * b'010		: 200
 287	 * b'011 (SYNCDL only)	: 300
 288	 * b'101		: 50
 289	 * b'110		: 150
 290	 */
 291	if (dtdl_or_syncdl % 100)
 292		return dtdl_or_syncdl / 100 + 5;
 293	else
 294		return dtdl_or_syncdl / 100;
 295}
 296
 297static u32 sh_msiof_spi_get_dtdl_and_syncdl(struct sh_msiof_spi_priv *p)
 298{
 299	u32 val;
 300
 301	if (!p->info)
 302		return 0;
 303
 304	/* check if DTDL and SYNCDL is allowed value */
 305	if (p->info->dtdl > 200 || p->info->syncdl > 300) {
 306		dev_warn(&p->pdev->dev, "DTDL or SYNCDL is too large\n");
 307		return 0;
 308	}
 309
 310	/* check if the sum of DTDL and SYNCDL becomes an integer value  */
 311	if ((p->info->dtdl + p->info->syncdl) % 100) {
 312		dev_warn(&p->pdev->dev, "the sum of DTDL/SYNCDL is not good\n");
 313		return 0;
 314	}
 315
 316	val = sh_msiof_get_delay_bit(p->info->dtdl) << MDR1_DTDL_SHIFT;
 317	val |= sh_msiof_get_delay_bit(p->info->syncdl) << MDR1_SYNCDL_SHIFT;
 318
 319	return val;
 320}
 321
 322static void sh_msiof_spi_set_pin_regs(struct sh_msiof_spi_priv *p,
 323				      u32 cpol, u32 cpha,
 324				      u32 tx_hi_z, u32 lsb_first, u32 cs_high)
 325{
 326	u32 tmp;
 327	int edge;
 328
 329	/*
 330	 * CPOL CPHA     TSCKIZ RSCKIZ TEDG REDG
 331	 *    0    0         10     10    1    1
 332	 *    0    1         10     10    0    0
 333	 *    1    0         11     11    0    0
 334	 *    1    1         11     11    1    1
 335	 */
 336	tmp = MDR1_SYNCMD_SPI | 1 << MDR1_FLD_SHIFT | MDR1_XXSTP;
 337	tmp |= !cs_high << MDR1_SYNCAC_SHIFT;
 338	tmp |= lsb_first << MDR1_BITLSB_SHIFT;
 339	tmp |= sh_msiof_spi_get_dtdl_and_syncdl(p);
 340	sh_msiof_write(p, TMDR1, tmp | MDR1_TRMD | TMDR1_PCON);
 341	if (p->master->flags & SPI_MASTER_MUST_TX) {
 342		/* These bits are reserved if RX needs TX */
 343		tmp &= ~0x0000ffff;
 344	}
 345	sh_msiof_write(p, RMDR1, tmp);
 346
 347	tmp = 0;
 348	tmp |= CTR_TSCKIZ_SCK | cpol << CTR_TSCKIZ_POL_SHIFT;
 349	tmp |= CTR_RSCKIZ_SCK | cpol << CTR_RSCKIZ_POL_SHIFT;
 350
 351	edge = cpol ^ !cpha;
 352
 353	tmp |= edge << CTR_TEDG_SHIFT;
 354	tmp |= edge << CTR_REDG_SHIFT;
 355	tmp |= tx_hi_z ? CTR_TXDIZ_HIZ : CTR_TXDIZ_LOW;
 356	sh_msiof_write(p, CTR, tmp);
 357}
 358
 359static void sh_msiof_spi_set_mode_regs(struct sh_msiof_spi_priv *p,
 360				       const void *tx_buf, void *rx_buf,
 361				       u32 bits, u32 words)
 362{
 363	u32 dr2 = MDR2_BITLEN1(bits) | MDR2_WDLEN1(words);
 364
 365	if (tx_buf || (p->master->flags & SPI_MASTER_MUST_TX))
 366		sh_msiof_write(p, TMDR2, dr2);
 367	else
 368		sh_msiof_write(p, TMDR2, dr2 | MDR2_GRPMASK1);
 369
 370	if (rx_buf)
 371		sh_msiof_write(p, RMDR2, dr2);
 
 
 372}
 373
 374static void sh_msiof_reset_str(struct sh_msiof_spi_priv *p)
 375{
 376	sh_msiof_write(p, STR, sh_msiof_read(p, STR));
 377}
 378
 379static void sh_msiof_spi_write_fifo_8(struct sh_msiof_spi_priv *p,
 380				      const void *tx_buf, int words, int fs)
 381{
 382	const u8 *buf_8 = tx_buf;
 383	int k;
 384
 385	for (k = 0; k < words; k++)
 386		sh_msiof_write(p, TFDR, buf_8[k] << fs);
 387}
 388
 389static void sh_msiof_spi_write_fifo_16(struct sh_msiof_spi_priv *p,
 390				       const void *tx_buf, int words, int fs)
 391{
 392	const u16 *buf_16 = tx_buf;
 393	int k;
 394
 395	for (k = 0; k < words; k++)
 396		sh_msiof_write(p, TFDR, buf_16[k] << fs);
 397}
 398
 399static void sh_msiof_spi_write_fifo_16u(struct sh_msiof_spi_priv *p,
 400					const void *tx_buf, int words, int fs)
 401{
 402	const u16 *buf_16 = tx_buf;
 403	int k;
 404
 405	for (k = 0; k < words; k++)
 406		sh_msiof_write(p, TFDR, get_unaligned(&buf_16[k]) << fs);
 407}
 408
 409static void sh_msiof_spi_write_fifo_32(struct sh_msiof_spi_priv *p,
 410				       const void *tx_buf, int words, int fs)
 411{
 412	const u32 *buf_32 = tx_buf;
 413	int k;
 414
 415	for (k = 0; k < words; k++)
 416		sh_msiof_write(p, TFDR, buf_32[k] << fs);
 417}
 418
 419static void sh_msiof_spi_write_fifo_32u(struct sh_msiof_spi_priv *p,
 420					const void *tx_buf, int words, int fs)
 421{
 422	const u32 *buf_32 = tx_buf;
 423	int k;
 424
 425	for (k = 0; k < words; k++)
 426		sh_msiof_write(p, TFDR, get_unaligned(&buf_32[k]) << fs);
 427}
 428
 429static void sh_msiof_spi_write_fifo_s32(struct sh_msiof_spi_priv *p,
 430					const void *tx_buf, int words, int fs)
 431{
 432	const u32 *buf_32 = tx_buf;
 433	int k;
 434
 435	for (k = 0; k < words; k++)
 436		sh_msiof_write(p, TFDR, swab32(buf_32[k] << fs));
 437}
 438
 439static void sh_msiof_spi_write_fifo_s32u(struct sh_msiof_spi_priv *p,
 440					 const void *tx_buf, int words, int fs)
 441{
 442	const u32 *buf_32 = tx_buf;
 443	int k;
 444
 445	for (k = 0; k < words; k++)
 446		sh_msiof_write(p, TFDR, swab32(get_unaligned(&buf_32[k]) << fs));
 447}
 448
 449static void sh_msiof_spi_read_fifo_8(struct sh_msiof_spi_priv *p,
 450				     void *rx_buf, int words, int fs)
 451{
 452	u8 *buf_8 = rx_buf;
 453	int k;
 454
 455	for (k = 0; k < words; k++)
 456		buf_8[k] = sh_msiof_read(p, RFDR) >> fs;
 457}
 458
 459static void sh_msiof_spi_read_fifo_16(struct sh_msiof_spi_priv *p,
 460				      void *rx_buf, int words, int fs)
 461{
 462	u16 *buf_16 = rx_buf;
 463	int k;
 464
 465	for (k = 0; k < words; k++)
 466		buf_16[k] = sh_msiof_read(p, RFDR) >> fs;
 467}
 468
 469static void sh_msiof_spi_read_fifo_16u(struct sh_msiof_spi_priv *p,
 470				       void *rx_buf, int words, int fs)
 471{
 472	u16 *buf_16 = rx_buf;
 473	int k;
 474
 475	for (k = 0; k < words; k++)
 476		put_unaligned(sh_msiof_read(p, RFDR) >> fs, &buf_16[k]);
 477}
 478
 479static void sh_msiof_spi_read_fifo_32(struct sh_msiof_spi_priv *p,
 480				      void *rx_buf, int words, int fs)
 481{
 482	u32 *buf_32 = rx_buf;
 483	int k;
 484
 485	for (k = 0; k < words; k++)
 486		buf_32[k] = sh_msiof_read(p, RFDR) >> fs;
 487}
 488
 489static void sh_msiof_spi_read_fifo_32u(struct sh_msiof_spi_priv *p,
 490				       void *rx_buf, int words, int fs)
 491{
 492	u32 *buf_32 = rx_buf;
 493	int k;
 494
 495	for (k = 0; k < words; k++)
 496		put_unaligned(sh_msiof_read(p, RFDR) >> fs, &buf_32[k]);
 497}
 498
 499static void sh_msiof_spi_read_fifo_s32(struct sh_msiof_spi_priv *p,
 500				       void *rx_buf, int words, int fs)
 501{
 502	u32 *buf_32 = rx_buf;
 503	int k;
 504
 505	for (k = 0; k < words; k++)
 506		buf_32[k] = swab32(sh_msiof_read(p, RFDR) >> fs);
 507}
 508
 509static void sh_msiof_spi_read_fifo_s32u(struct sh_msiof_spi_priv *p,
 510				       void *rx_buf, int words, int fs)
 511{
 512	u32 *buf_32 = rx_buf;
 513	int k;
 514
 515	for (k = 0; k < words; k++)
 516		put_unaligned(swab32(sh_msiof_read(p, RFDR) >> fs), &buf_32[k]);
 517}
 518
 519static int sh_msiof_spi_setup(struct spi_device *spi)
 520{
 521	struct device_node	*np = spi->master->dev.of_node;
 522	struct sh_msiof_spi_priv *p = spi_master_get_devdata(spi->master);
 523
 524	pm_runtime_get_sync(&p->pdev->dev);
 525
 526	if (!np) {
 527		/*
 528		 * Use spi->controller_data for CS (same strategy as spi_gpio),
 529		 * if any. otherwise let HW control CS
 530		 */
 531		spi->cs_gpio = (uintptr_t)spi->controller_data;
 532	}
 533
 534	/* Configure pins before deasserting CS */
 535	sh_msiof_spi_set_pin_regs(p, !!(spi->mode & SPI_CPOL),
 536				  !!(spi->mode & SPI_CPHA),
 537				  !!(spi->mode & SPI_3WIRE),
 538				  !!(spi->mode & SPI_LSB_FIRST),
 539				  !!(spi->mode & SPI_CS_HIGH));
 540
 541	if (spi->cs_gpio >= 0)
 542		gpio_set_value(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH));
 543
 544
 545	pm_runtime_put(&p->pdev->dev);
 546
 547	return 0;
 
 548}
 549
 550static int sh_msiof_prepare_message(struct spi_master *master,
 551				    struct spi_message *msg)
 552{
 553	struct sh_msiof_spi_priv *p = spi_master_get_devdata(master);
 554	const struct spi_device *spi = msg->spi;
 555
 556	/* Configure pins before asserting CS */
 557	sh_msiof_spi_set_pin_regs(p, !!(spi->mode & SPI_CPOL),
 558				  !!(spi->mode & SPI_CPHA),
 559				  !!(spi->mode & SPI_3WIRE),
 560				  !!(spi->mode & SPI_LSB_FIRST),
 561				  !!(spi->mode & SPI_CS_HIGH));
 562	return 0;
 563}
 564
 565static int sh_msiof_spi_start(struct sh_msiof_spi_priv *p, void *rx_buf)
 
 566{
 567	int ret;
 568
 569	/* setup clock and rx/tx signals */
 570	ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TSCKE);
 571	if (rx_buf && !ret)
 572		ret = sh_msiof_modify_ctr_wait(p, 0, CTR_RXE);
 573	if (!ret)
 574		ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TXE);
 575
 576	/* start by setting frame bit */
 577	if (!ret)
 578		ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TFSE);
 
 
 579
 580	return ret;
 581}
 582
 583static int sh_msiof_spi_stop(struct sh_msiof_spi_priv *p, void *rx_buf)
 584{
 585	int ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 586
 587	/* shut down frame, rx/tx and clock signals */
 588	ret = sh_msiof_modify_ctr_wait(p, CTR_TFSE, 0);
 589	if (!ret)
 590		ret = sh_msiof_modify_ctr_wait(p, CTR_TXE, 0);
 591	if (rx_buf && !ret)
 592		ret = sh_msiof_modify_ctr_wait(p, CTR_RXE, 0);
 593	if (!ret)
 594		ret = sh_msiof_modify_ctr_wait(p, CTR_TSCKE, 0);
 595
 596	return ret;
 
 
 
 
 
 
 
 
 597}
 598
 599static int sh_msiof_spi_txrx_once(struct sh_msiof_spi_priv *p,
 600				  void (*tx_fifo)(struct sh_msiof_spi_priv *,
 601						  const void *, int, int),
 602				  void (*rx_fifo)(struct sh_msiof_spi_priv *,
 603						  void *, int, int),
 604				  const void *tx_buf, void *rx_buf,
 605				  int words, int bits)
 606{
 607	int fifo_shift;
 608	int ret;
 609
 610	/* limit maximum word transfer to rx/tx fifo size */
 611	if (tx_buf)
 612		words = min_t(int, words, p->tx_fifo_size);
 613	if (rx_buf)
 614		words = min_t(int, words, p->rx_fifo_size);
 615
 616	/* the fifo contents need shifting */
 617	fifo_shift = 32 - bits;
 618
 619	/* default FIFO watermarks for PIO */
 620	sh_msiof_write(p, FCTR, 0);
 621
 622	/* setup msiof transfer mode registers */
 623	sh_msiof_spi_set_mode_regs(p, tx_buf, rx_buf, bits, words);
 624	sh_msiof_write(p, IER, IER_TEOFE | IER_REOFE);
 625
 626	/* write tx fifo */
 627	if (tx_buf)
 628		tx_fifo(p, tx_buf, words, fifo_shift);
 629
 630	reinit_completion(&p->done);
 
 
 
 
 631
 632	ret = sh_msiof_spi_start(p, rx_buf);
 
 
 633	if (ret) {
 634		dev_err(&p->pdev->dev, "failed to start hardware\n");
 635		goto stop_ier;
 636	}
 637
 638	/* wait for tx fifo to be emptied / rx fifo to be filled */
 639	if (!wait_for_completion_timeout(&p->done, HZ)) {
 640		dev_err(&p->pdev->dev, "PIO timeout\n");
 641		ret = -ETIMEDOUT;
 642		goto stop_reset;
 643	}
 644
 645	/* read rx fifo */
 646	if (rx_buf)
 647		rx_fifo(p, rx_buf, words, fifo_shift);
 648
 649	/* clear status bits */
 650	sh_msiof_reset_str(p);
 651
 652	ret = sh_msiof_spi_stop(p, rx_buf);
 
 
 
 
 
 653	if (ret) {
 654		dev_err(&p->pdev->dev, "failed to shut down hardware\n");
 655		return ret;
 656	}
 657
 658	return words;
 659
 660stop_reset:
 661	sh_msiof_reset_str(p);
 662	sh_msiof_spi_stop(p, rx_buf);
 663stop_ier:
 664	sh_msiof_write(p, IER, 0);
 665	return ret;
 666}
 667
 668static void sh_msiof_dma_complete(void *arg)
 669{
 670	struct sh_msiof_spi_priv *p = arg;
 671
 672	sh_msiof_write(p, IER, 0);
 673	complete(&p->done);
 674}
 675
 676static int sh_msiof_dma_once(struct sh_msiof_spi_priv *p, const void *tx,
 677			     void *rx, unsigned int len)
 678{
 679	u32 ier_bits = 0;
 680	struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL;
 681	dma_cookie_t cookie;
 682	int ret;
 683
 684	/* First prepare and submit the DMA request(s), as this may fail */
 685	if (rx) {
 686		ier_bits |= IER_RDREQE | IER_RDMAE;
 687		desc_rx = dmaengine_prep_slave_single(p->master->dma_rx,
 688					p->rx_dma_addr, len, DMA_FROM_DEVICE,
 689					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 690		if (!desc_rx)
 691			return -EAGAIN;
 692
 693		desc_rx->callback = sh_msiof_dma_complete;
 694		desc_rx->callback_param = p;
 695		cookie = dmaengine_submit(desc_rx);
 696		if (dma_submit_error(cookie))
 697			return cookie;
 698	}
 699
 700	if (tx) {
 701		ier_bits |= IER_TDREQE | IER_TDMAE;
 702		dma_sync_single_for_device(p->master->dma_tx->device->dev,
 703					   p->tx_dma_addr, len, DMA_TO_DEVICE);
 704		desc_tx = dmaengine_prep_slave_single(p->master->dma_tx,
 705					p->tx_dma_addr, len, DMA_TO_DEVICE,
 706					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 707		if (!desc_tx) {
 708			ret = -EAGAIN;
 709			goto no_dma_tx;
 710		}
 711
 712		if (rx) {
 713			/* No callback */
 714			desc_tx->callback = NULL;
 715		} else {
 716			desc_tx->callback = sh_msiof_dma_complete;
 717			desc_tx->callback_param = p;
 718		}
 719		cookie = dmaengine_submit(desc_tx);
 720		if (dma_submit_error(cookie)) {
 721			ret = cookie;
 722			goto no_dma_tx;
 723		}
 724	}
 725
 726	/* 1 stage FIFO watermarks for DMA */
 727	sh_msiof_write(p, FCTR, FCTR_TFWM_1 | FCTR_RFWM_1);
 728
 729	/* setup msiof transfer mode registers (32-bit words) */
 730	sh_msiof_spi_set_mode_regs(p, tx, rx, 32, len / 4);
 731
 732	sh_msiof_write(p, IER, ier_bits);
 733
 734	reinit_completion(&p->done);
 735
 736	/* Now start DMA */
 737	if (rx)
 738		dma_async_issue_pending(p->master->dma_rx);
 739	if (tx)
 740		dma_async_issue_pending(p->master->dma_tx);
 741
 742	ret = sh_msiof_spi_start(p, rx);
 743	if (ret) {
 744		dev_err(&p->pdev->dev, "failed to start hardware\n");
 745		goto stop_dma;
 746	}
 747
 748	/* wait for tx fifo to be emptied / rx fifo to be filled */
 749	if (!wait_for_completion_timeout(&p->done, HZ)) {
 750		dev_err(&p->pdev->dev, "DMA timeout\n");
 751		ret = -ETIMEDOUT;
 752		goto stop_reset;
 753	}
 754
 755	/* clear status bits */
 756	sh_msiof_reset_str(p);
 757
 758	ret = sh_msiof_spi_stop(p, rx);
 759	if (ret) {
 760		dev_err(&p->pdev->dev, "failed to shut down hardware\n");
 761		return ret;
 762	}
 763
 764	if (rx)
 765		dma_sync_single_for_cpu(p->master->dma_rx->device->dev,
 766					p->rx_dma_addr, len,
 767					DMA_FROM_DEVICE);
 768
 769	return 0;
 770
 771stop_reset:
 772	sh_msiof_reset_str(p);
 773	sh_msiof_spi_stop(p, rx);
 774stop_dma:
 775	if (tx)
 776		dmaengine_terminate_all(p->master->dma_tx);
 777no_dma_tx:
 778	if (rx)
 779		dmaengine_terminate_all(p->master->dma_rx);
 780	sh_msiof_write(p, IER, 0);
 781	return ret;
 782}
 783
 784static void copy_bswap32(u32 *dst, const u32 *src, unsigned int words)
 785{
 786	/* src or dst can be unaligned, but not both */
 787	if ((unsigned long)src & 3) {
 788		while (words--) {
 789			*dst++ = swab32(get_unaligned(src));
 790			src++;
 791		}
 792	} else if ((unsigned long)dst & 3) {
 793		while (words--) {
 794			put_unaligned(swab32(*src++), dst);
 795			dst++;
 796		}
 797	} else {
 798		while (words--)
 799			*dst++ = swab32(*src++);
 800	}
 801}
 802
 803static void copy_wswap32(u32 *dst, const u32 *src, unsigned int words)
 804{
 805	/* src or dst can be unaligned, but not both */
 806	if ((unsigned long)src & 3) {
 807		while (words--) {
 808			*dst++ = swahw32(get_unaligned(src));
 809			src++;
 810		}
 811	} else if ((unsigned long)dst & 3) {
 812		while (words--) {
 813			put_unaligned(swahw32(*src++), dst);
 814			dst++;
 815		}
 816	} else {
 817		while (words--)
 818			*dst++ = swahw32(*src++);
 819	}
 820}
 821
 822static void copy_plain32(u32 *dst, const u32 *src, unsigned int words)
 823{
 824	memcpy(dst, src, words * 4);
 825}
 826
 827static int sh_msiof_transfer_one(struct spi_master *master,
 828				 struct spi_device *spi,
 829				 struct spi_transfer *t)
 830{
 831	struct sh_msiof_spi_priv *p = spi_master_get_devdata(master);
 832	void (*copy32)(u32 *, const u32 *, unsigned int);
 833	void (*tx_fifo)(struct sh_msiof_spi_priv *, const void *, int, int);
 834	void (*rx_fifo)(struct sh_msiof_spi_priv *, void *, int, int);
 835	const void *tx_buf = t->tx_buf;
 836	void *rx_buf = t->rx_buf;
 837	unsigned int len = t->len;
 838	unsigned int bits = t->bits_per_word;
 839	unsigned int bytes_per_word;
 840	unsigned int words;
 841	int n;
 842	bool swab;
 843	int ret;
 844
 845	/* setup clocks (clock already enabled in chipselect()) */
 846	sh_msiof_spi_set_clk_regs(p, clk_get_rate(p->clk), t->speed_hz);
 847
 848	while (master->dma_tx && len > 15) {
 849		/*
 850		 *  DMA supports 32-bit words only, hence pack 8-bit and 16-bit
 851		 *  words, with byte resp. word swapping.
 852		 */
 853		unsigned int l = 0;
 854
 855		if (tx_buf)
 856			l = min(len, p->tx_fifo_size * 4);
 857		if (rx_buf)
 858			l = min(len, p->rx_fifo_size * 4);
 859
 860		if (bits <= 8) {
 861			if (l & 3)
 862				break;
 863			copy32 = copy_bswap32;
 864		} else if (bits <= 16) {
 865			if (l & 1)
 866				break;
 867			copy32 = copy_wswap32;
 868		} else {
 869			copy32 = copy_plain32;
 870		}
 871
 872		if (tx_buf)
 873			copy32(p->tx_dma_page, tx_buf, l / 4);
 874
 875		ret = sh_msiof_dma_once(p, tx_buf, rx_buf, l);
 876		if (ret == -EAGAIN) {
 877			pr_warn_once("%s %s: DMA not available, falling back to PIO\n",
 878				     dev_driver_string(&p->pdev->dev),
 879				     dev_name(&p->pdev->dev));
 880			break;
 881		}
 882		if (ret)
 883			return ret;
 884
 885		if (rx_buf) {
 886			copy32(rx_buf, p->rx_dma_page, l / 4);
 887			rx_buf += l;
 888		}
 889		if (tx_buf)
 890			tx_buf += l;
 891
 892		len -= l;
 893		if (!len)
 894			return 0;
 895	}
 896
 897	if (bits <= 8 && len > 15 && !(len & 3)) {
 898		bits = 32;
 899		swab = true;
 900	} else {
 901		swab = false;
 902	}
 903
 904	/* setup bytes per word and fifo read/write functions */
 905	if (bits <= 8) {
 906		bytes_per_word = 1;
 907		tx_fifo = sh_msiof_spi_write_fifo_8;
 908		rx_fifo = sh_msiof_spi_read_fifo_8;
 909	} else if (bits <= 16) {
 910		bytes_per_word = 2;
 911		if ((unsigned long)tx_buf & 0x01)
 912			tx_fifo = sh_msiof_spi_write_fifo_16u;
 913		else
 914			tx_fifo = sh_msiof_spi_write_fifo_16;
 915
 916		if ((unsigned long)rx_buf & 0x01)
 917			rx_fifo = sh_msiof_spi_read_fifo_16u;
 918		else
 919			rx_fifo = sh_msiof_spi_read_fifo_16;
 920	} else if (swab) {
 921		bytes_per_word = 4;
 922		if ((unsigned long)tx_buf & 0x03)
 923			tx_fifo = sh_msiof_spi_write_fifo_s32u;
 924		else
 925			tx_fifo = sh_msiof_spi_write_fifo_s32;
 926
 927		if ((unsigned long)rx_buf & 0x03)
 928			rx_fifo = sh_msiof_spi_read_fifo_s32u;
 929		else
 930			rx_fifo = sh_msiof_spi_read_fifo_s32;
 931	} else {
 932		bytes_per_word = 4;
 933		if ((unsigned long)tx_buf & 0x03)
 934			tx_fifo = sh_msiof_spi_write_fifo_32u;
 935		else
 936			tx_fifo = sh_msiof_spi_write_fifo_32;
 937
 938		if ((unsigned long)rx_buf & 0x03)
 939			rx_fifo = sh_msiof_spi_read_fifo_32u;
 940		else
 941			rx_fifo = sh_msiof_spi_read_fifo_32;
 942	}
 943
 
 
 
 
 944	/* transfer in fifo sized chunks */
 945	words = len / bytes_per_word;
 
 946
 947	while (words > 0) {
 948		n = sh_msiof_spi_txrx_once(p, tx_fifo, rx_fifo, tx_buf, rx_buf,
 
 
 
 
 949					   words, bits);
 950		if (n < 0)
 951			return n;
 952
 953		if (tx_buf)
 954			tx_buf += n * bytes_per_word;
 955		if (rx_buf)
 956			rx_buf += n * bytes_per_word;
 957		words -= n;
 958	}
 959
 960	return 0;
 961}
 962
 963static const struct sh_msiof_chipdata sh_data = {
 964	.tx_fifo_size = 64,
 965	.rx_fifo_size = 64,
 966	.master_flags = 0,
 967};
 968
 969static const struct sh_msiof_chipdata r8a779x_data = {
 970	.tx_fifo_size = 64,
 971	.rx_fifo_size = 64,
 972	.master_flags = SPI_MASTER_MUST_TX,
 973};
 974
 975static const struct of_device_id sh_msiof_match[] = {
 976	{ .compatible = "renesas,sh-mobile-msiof", .data = &sh_data },
 977	{ .compatible = "renesas,msiof-r8a7790",   .data = &r8a779x_data },
 978	{ .compatible = "renesas,msiof-r8a7791",   .data = &r8a779x_data },
 979	{ .compatible = "renesas,msiof-r8a7792",   .data = &r8a779x_data },
 980	{ .compatible = "renesas,msiof-r8a7793",   .data = &r8a779x_data },
 981	{ .compatible = "renesas,msiof-r8a7794",   .data = &r8a779x_data },
 982	{ .compatible = "renesas,rcar-gen2-msiof", .data = &r8a779x_data },
 983	{ .compatible = "renesas,msiof-r8a7796",   .data = &r8a779x_data },
 984	{ .compatible = "renesas,rcar-gen3-msiof", .data = &r8a779x_data },
 985	{ .compatible = "renesas,sh-msiof",        .data = &sh_data }, /* Deprecated */
 986	{},
 987};
 988MODULE_DEVICE_TABLE(of, sh_msiof_match);
 989
 990#ifdef CONFIG_OF
 991static struct sh_msiof_spi_info *sh_msiof_spi_parse_dt(struct device *dev)
 992{
 993	struct sh_msiof_spi_info *info;
 994	struct device_node *np = dev->of_node;
 995	u32 num_cs = 1;
 996
 997	info = devm_kzalloc(dev, sizeof(struct sh_msiof_spi_info), GFP_KERNEL);
 998	if (!info)
 999		return NULL;
1000
1001	/* Parse the MSIOF properties */
1002	of_property_read_u32(np, "num-cs", &num_cs);
1003	of_property_read_u32(np, "renesas,tx-fifo-size",
1004					&info->tx_fifo_override);
1005	of_property_read_u32(np, "renesas,rx-fifo-size",
1006					&info->rx_fifo_override);
1007	of_property_read_u32(np, "renesas,dtdl", &info->dtdl);
1008	of_property_read_u32(np, "renesas,syncdl", &info->syncdl);
1009
1010	info->num_chipselect = num_cs;
1011
1012	return info;
1013}
1014#else
1015static struct sh_msiof_spi_info *sh_msiof_spi_parse_dt(struct device *dev)
1016{
1017	return NULL;
1018}
1019#endif
1020
1021static struct dma_chan *sh_msiof_request_dma_chan(struct device *dev,
1022	enum dma_transfer_direction dir, unsigned int id, dma_addr_t port_addr)
1023{
1024	dma_cap_mask_t mask;
1025	struct dma_chan *chan;
1026	struct dma_slave_config cfg;
1027	int ret;
1028
1029	dma_cap_zero(mask);
1030	dma_cap_set(DMA_SLAVE, mask);
1031
1032	chan = dma_request_slave_channel_compat(mask, shdma_chan_filter,
1033				(void *)(unsigned long)id, dev,
1034				dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1035	if (!chan) {
1036		dev_warn(dev, "dma_request_slave_channel_compat failed\n");
1037		return NULL;
1038	}
1039
1040	memset(&cfg, 0, sizeof(cfg));
1041	cfg.direction = dir;
1042	if (dir == DMA_MEM_TO_DEV) {
1043		cfg.dst_addr = port_addr;
1044		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1045	} else {
1046		cfg.src_addr = port_addr;
1047		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1048	}
1049
1050	ret = dmaengine_slave_config(chan, &cfg);
1051	if (ret) {
1052		dev_warn(dev, "dmaengine_slave_config failed %d\n", ret);
1053		dma_release_channel(chan);
1054		return NULL;
1055	}
1056
1057	return chan;
1058}
1059
1060static int sh_msiof_request_dma(struct sh_msiof_spi_priv *p)
1061{
1062	struct platform_device *pdev = p->pdev;
1063	struct device *dev = &pdev->dev;
1064	const struct sh_msiof_spi_info *info = dev_get_platdata(dev);
1065	unsigned int dma_tx_id, dma_rx_id;
1066	const struct resource *res;
1067	struct spi_master *master;
1068	struct device *tx_dev, *rx_dev;
1069
1070	if (dev->of_node) {
1071		/* In the OF case we will get the slave IDs from the DT */
1072		dma_tx_id = 0;
1073		dma_rx_id = 0;
1074	} else if (info && info->dma_tx_id && info->dma_rx_id) {
1075		dma_tx_id = info->dma_tx_id;
1076		dma_rx_id = info->dma_rx_id;
1077	} else {
1078		/* The driver assumes no error */
1079		return 0;
1080	}
1081
1082	/* The DMA engine uses the second register set, if present */
1083	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1084	if (!res)
1085		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1086
1087	master = p->master;
1088	master->dma_tx = sh_msiof_request_dma_chan(dev, DMA_MEM_TO_DEV,
1089						   dma_tx_id,
1090						   res->start + TFDR);
1091	if (!master->dma_tx)
1092		return -ENODEV;
1093
1094	master->dma_rx = sh_msiof_request_dma_chan(dev, DMA_DEV_TO_MEM,
1095						   dma_rx_id,
1096						   res->start + RFDR);
1097	if (!master->dma_rx)
1098		goto free_tx_chan;
1099
1100	p->tx_dma_page = (void *)__get_free_page(GFP_KERNEL | GFP_DMA);
1101	if (!p->tx_dma_page)
1102		goto free_rx_chan;
1103
1104	p->rx_dma_page = (void *)__get_free_page(GFP_KERNEL | GFP_DMA);
1105	if (!p->rx_dma_page)
1106		goto free_tx_page;
1107
1108	tx_dev = master->dma_tx->device->dev;
1109	p->tx_dma_addr = dma_map_single(tx_dev, p->tx_dma_page, PAGE_SIZE,
1110					DMA_TO_DEVICE);
1111	if (dma_mapping_error(tx_dev, p->tx_dma_addr))
1112		goto free_rx_page;
1113
1114	rx_dev = master->dma_rx->device->dev;
1115	p->rx_dma_addr = dma_map_single(rx_dev, p->rx_dma_page, PAGE_SIZE,
1116					DMA_FROM_DEVICE);
1117	if (dma_mapping_error(rx_dev, p->rx_dma_addr))
1118		goto unmap_tx_page;
1119
1120	dev_info(dev, "DMA available");
1121	return 0;
1122
1123unmap_tx_page:
1124	dma_unmap_single(tx_dev, p->tx_dma_addr, PAGE_SIZE, DMA_TO_DEVICE);
1125free_rx_page:
1126	free_page((unsigned long)p->rx_dma_page);
1127free_tx_page:
1128	free_page((unsigned long)p->tx_dma_page);
1129free_rx_chan:
1130	dma_release_channel(master->dma_rx);
1131free_tx_chan:
1132	dma_release_channel(master->dma_tx);
1133	master->dma_tx = NULL;
1134	return -ENODEV;
1135}
1136
1137static void sh_msiof_release_dma(struct sh_msiof_spi_priv *p)
1138{
1139	struct spi_master *master = p->master;
1140	struct device *dev;
1141
1142	if (!master->dma_tx)
1143		return;
1144
1145	dev = &p->pdev->dev;
1146	dma_unmap_single(master->dma_rx->device->dev, p->rx_dma_addr,
1147			 PAGE_SIZE, DMA_FROM_DEVICE);
1148	dma_unmap_single(master->dma_tx->device->dev, p->tx_dma_addr,
1149			 PAGE_SIZE, DMA_TO_DEVICE);
1150	free_page((unsigned long)p->rx_dma_page);
1151	free_page((unsigned long)p->tx_dma_page);
1152	dma_release_channel(master->dma_rx);
1153	dma_release_channel(master->dma_tx);
1154}
1155
1156static int sh_msiof_spi_probe(struct platform_device *pdev)
1157{
1158	struct resource	*r;
1159	struct spi_master *master;
1160	const struct sh_msiof_chipdata *chipdata;
1161	const struct of_device_id *of_id;
1162	struct sh_msiof_spi_priv *p;
 
1163	int i;
1164	int ret;
1165
1166	master = spi_alloc_master(&pdev->dev, sizeof(struct sh_msiof_spi_priv));
1167	if (master == NULL) {
1168		dev_err(&pdev->dev, "failed to allocate spi master\n");
1169		return -ENOMEM;
 
1170	}
1171
1172	p = spi_master_get_devdata(master);
1173
1174	platform_set_drvdata(pdev, p);
1175	p->master = master;
1176
1177	of_id = of_match_device(sh_msiof_match, &pdev->dev);
1178	if (of_id) {
1179		chipdata = of_id->data;
1180		p->info = sh_msiof_spi_parse_dt(&pdev->dev);
1181	} else {
1182		chipdata = (const void *)pdev->id_entry->driver_data;
1183		p->info = dev_get_platdata(&pdev->dev);
1184	}
1185
1186	if (!p->info) {
1187		dev_err(&pdev->dev, "failed to obtain device info\n");
1188		ret = -ENXIO;
1189		goto err1;
1190	}
1191
1192	init_completion(&p->done);
1193
1194	p->clk = devm_clk_get(&pdev->dev, NULL);
 
1195	if (IS_ERR(p->clk)) {
1196		dev_err(&pdev->dev, "cannot get clock\n");
1197		ret = PTR_ERR(p->clk);
1198		goto err1;
1199	}
1200
 
1201	i = platform_get_irq(pdev, 0);
1202	if (i < 0) {
1203		dev_err(&pdev->dev, "cannot get platform IRQ\n");
1204		ret = -ENOENT;
1205		goto err1;
1206	}
1207
1208	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1209	p->mapbase = devm_ioremap_resource(&pdev->dev, r);
1210	if (IS_ERR(p->mapbase)) {
1211		ret = PTR_ERR(p->mapbase);
1212		goto err1;
1213	}
1214
1215	ret = devm_request_irq(&pdev->dev, i, sh_msiof_spi_irq, 0,
1216			       dev_name(&pdev->dev), p);
1217	if (ret) {
1218		dev_err(&pdev->dev, "unable to request irq\n");
1219		goto err1;
1220	}
1221
1222	p->pdev = pdev;
1223	pm_runtime_enable(&pdev->dev);
1224
 
 
 
 
1225	/* Platform data may override FIFO sizes */
1226	p->tx_fifo_size = chipdata->tx_fifo_size;
1227	p->rx_fifo_size = chipdata->rx_fifo_size;
1228	if (p->info->tx_fifo_override)
1229		p->tx_fifo_size = p->info->tx_fifo_override;
1230	if (p->info->rx_fifo_override)
1231		p->rx_fifo_size = p->info->rx_fifo_override;
1232
1233	/* init master code */
1234	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1235	master->mode_bits |= SPI_LSB_FIRST | SPI_3WIRE;
1236	master->flags = chipdata->master_flags;
1237	master->bus_num = pdev->id;
1238	master->dev.of_node = pdev->dev.of_node;
1239	master->num_chipselect = p->info->num_chipselect;
1240	master->setup = sh_msiof_spi_setup;
1241	master->prepare_message = sh_msiof_prepare_message;
1242	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 32);
1243	master->auto_runtime_pm = true;
1244	master->transfer_one = sh_msiof_transfer_one;
1245
1246	ret = sh_msiof_request_dma(p);
1247	if (ret < 0)
1248		dev_warn(&pdev->dev, "DMA not available, using PIO\n");
1249
1250	ret = devm_spi_register_master(&pdev->dev, master);
1251	if (ret < 0) {
1252		dev_err(&pdev->dev, "spi_register_master error.\n");
1253		goto err2;
1254	}
1255
1256	return 0;
 
 
1257
 
 
 
1258 err2:
1259	sh_msiof_release_dma(p);
1260	pm_runtime_disable(&pdev->dev);
1261 err1:
1262	spi_master_put(master);
 
1263	return ret;
1264}
1265
1266static int sh_msiof_spi_remove(struct platform_device *pdev)
1267{
1268	struct sh_msiof_spi_priv *p = platform_get_drvdata(pdev);
 
1269
1270	sh_msiof_release_dma(p);
1271	pm_runtime_disable(&pdev->dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1272	return 0;
1273}
1274
1275static const struct platform_device_id spi_driver_ids[] = {
1276	{ "spi_sh_msiof",	(kernel_ulong_t)&sh_data },
1277	{},
1278};
1279MODULE_DEVICE_TABLE(platform, spi_driver_ids);
1280
1281static struct platform_driver sh_msiof_spi_drv = {
1282	.probe		= sh_msiof_spi_probe,
1283	.remove		= sh_msiof_spi_remove,
1284	.id_table	= spi_driver_ids,
1285	.driver		= {
1286		.name		= "spi_sh_msiof",
1287		.of_match_table = of_match_ptr(sh_msiof_match),
 
1288	},
1289};
1290module_platform_driver(sh_msiof_spi_drv);
 
 
 
 
 
 
 
 
 
 
 
1291
1292MODULE_DESCRIPTION("SuperH MSIOF SPI Master Interface Driver");
1293MODULE_AUTHOR("Magnus Damm");
1294MODULE_LICENSE("GPL v2");
1295MODULE_ALIAS("platform:spi_sh_msiof");