xref: /linux/drivers/spi/spi-sh-msiof.c (revision 93df8a1ed6231727c5db94a80b1a6bd5ee67cec3) 
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 
37 struct sh_msiof_chipdata {
38 	u16 tx_fifo_size;
39 	u16 rx_fifo_size;
40 	u16 master_flags;
41 };
42 
43 struct sh_msiof_spi_priv {
44 	struct spi_master *master;
45 	void __iomem *mapbase;
46 	struct clk *clk;
47 	struct platform_device *pdev;
48 	const struct sh_msiof_chipdata *chipdata;
49 	struct sh_msiof_spi_info *info;
50 	struct completion done;
51 	int tx_fifo_size;
52 	int rx_fifo_size;
53 	void *tx_dma_page;
54 	void *rx_dma_page;
55 	dma_addr_t tx_dma_addr;
56 	dma_addr_t rx_dma_addr;
57 };
58 
59 #define TMDR1	0x00	/* Transmit Mode Register 1 */
60 #define TMDR2	0x04	/* Transmit Mode Register 2 */
61 #define TMDR3	0x08	/* Transmit Mode Register 3 */
62 #define RMDR1	0x10	/* Receive Mode Register 1 */
63 #define RMDR2	0x14	/* Receive Mode Register 2 */
64 #define RMDR3	0x18	/* Receive Mode Register 3 */
65 #define TSCR	0x20	/* Transmit Clock Select Register */
66 #define RSCR	0x22	/* Receive Clock Select Register (SH, A1, APE6) */
67 #define CTR	0x28	/* Control Register */
68 #define FCTR	0x30	/* FIFO Control Register */
69 #define STR	0x40	/* Status Register */
70 #define IER	0x44	/* Interrupt Enable Register */
71 #define TDR1	0x48	/* Transmit Control Data Register 1 (SH, A1) */
72 #define TDR2	0x4c	/* Transmit Control Data Register 2 (SH, A1) */
73 #define TFDR	0x50	/* Transmit FIFO Data Register */
74 #define RDR1	0x58	/* Receive Control Data Register 1 (SH, A1) */
75 #define RDR2	0x5c	/* Receive Control Data Register 2 (SH, A1) */
76 #define RFDR	0x60	/* Receive FIFO Data Register */
77 
78 /* TMDR1 and RMDR1 */
79 #define MDR1_TRMD	 0x80000000 /* Transfer Mode (1 = Master mode) */
80 #define MDR1_SYNCMD_MASK 0x30000000 /* SYNC Mode */
81 #define MDR1_SYNCMD_SPI	 0x20000000 /*   Level mode/SPI */
82 #define MDR1_SYNCMD_LR	 0x30000000 /*   L/R mode */
83 #define MDR1_SYNCAC_SHIFT	 25 /* Sync Polarity (1 = Active-low) */
84 #define MDR1_BITLSB_SHIFT	 24 /* MSB/LSB First (1 = LSB first) */
85 #define MDR1_DTDL_SHIFT		 20 /* Data Pin Bit Delay for MSIOF_SYNC */
86 #define MDR1_SYNCDL_SHIFT	 16 /* Frame Sync Signal Timing Delay */
87 #define MDR1_FLD_MASK	 0x0000000c /* Frame Sync Signal Interval (0-3) */
88 #define MDR1_FLD_SHIFT		  2
89 #define MDR1_XXSTP	 0x00000001 /* Transmission/Reception Stop on FIFO */
90 /* TMDR1 */
91 #define TMDR1_PCON	 0x40000000 /* Transfer Signal Connection */
92 
93 /* TMDR2 and RMDR2 */
94 #define MDR2_BITLEN1(i)	(((i) - 1) << 24) /* Data Size (8-32 bits) */
95 #define MDR2_WDLEN1(i)	(((i) - 1) << 16) /* Word Count (1-64/256 (SH, A1))) */
96 #define MDR2_GRPMASK1	0x00000001 /* Group Output Mask 1 (SH, A1) */
97 
98 #define MAX_WDLEN	256U
99 
100 /* TSCR and RSCR */
101 #define SCR_BRPS_MASK	    0x1f00 /* Prescaler Setting (1-32) */
102 #define SCR_BRPS(i)	(((i) - 1) << 8)
103 #define SCR_BRDV_MASK	    0x0007 /* Baud Rate Generator's Division Ratio */
104 #define SCR_BRDV_DIV_2	    0x0000
105 #define SCR_BRDV_DIV_4	    0x0001
106 #define SCR_BRDV_DIV_8	    0x0002
107 #define SCR_BRDV_DIV_16	    0x0003
108 #define SCR_BRDV_DIV_32	    0x0004
109 #define SCR_BRDV_DIV_1	    0x0007
110 
111 /* CTR */
112 #define CTR_TSCKIZ_MASK	0xc0000000 /* Transmit Clock I/O Polarity Select */
113 #define CTR_TSCKIZ_SCK	0x80000000 /*   Disable SCK when TX disabled */
114 #define CTR_TSCKIZ_POL_SHIFT	30 /*   Transmit Clock Polarity */
115 #define CTR_RSCKIZ_MASK	0x30000000 /* Receive Clock Polarity Select */
116 #define CTR_RSCKIZ_SCK	0x20000000 /*   Must match CTR_TSCKIZ_SCK */
117 #define CTR_RSCKIZ_POL_SHIFT	28 /*   Receive Clock Polarity */
118 #define CTR_TEDG_SHIFT		27 /* Transmit Timing (1 = falling edge) */
119 #define CTR_REDG_SHIFT		26 /* Receive Timing (1 = falling edge) */
120 #define CTR_TXDIZ_MASK	0x00c00000 /* Pin Output When TX is Disabled */
121 #define CTR_TXDIZ_LOW	0x00000000 /*   0 */
122 #define CTR_TXDIZ_HIGH	0x00400000 /*   1 */
123 #define CTR_TXDIZ_HIZ	0x00800000 /*   High-impedance */
124 #define CTR_TSCKE	0x00008000 /* Transmit Serial Clock Output Enable */
125 #define CTR_TFSE	0x00004000 /* Transmit Frame Sync Signal Output Enable */
126 #define CTR_TXE		0x00000200 /* Transmit Enable */
127 #define CTR_RXE		0x00000100 /* Receive Enable */
128 
129 /* FCTR */
130 #define FCTR_TFWM_MASK	0xe0000000 /* Transmit FIFO Watermark */
131 #define FCTR_TFWM_64	0x00000000 /*  Transfer Request when 64 empty stages */
132 #define FCTR_TFWM_32	0x20000000 /*  Transfer Request when 32 empty stages */
133 #define FCTR_TFWM_24	0x40000000 /*  Transfer Request when 24 empty stages */
134 #define FCTR_TFWM_16	0x60000000 /*  Transfer Request when 16 empty stages */
135 #define FCTR_TFWM_12	0x80000000 /*  Transfer Request when 12 empty stages */
136 #define FCTR_TFWM_8	0xa0000000 /*  Transfer Request when 8 empty stages */
137 #define FCTR_TFWM_4	0xc0000000 /*  Transfer Request when 4 empty stages */
138 #define FCTR_TFWM_1	0xe0000000 /*  Transfer Request when 1 empty stage */
139 #define FCTR_TFUA_MASK	0x07f00000 /* Transmit FIFO Usable Area */
140 #define FCTR_TFUA_SHIFT		20
141 #define FCTR_TFUA(i)	((i) << FCTR_TFUA_SHIFT)
142 #define FCTR_RFWM_MASK	0x0000e000 /* Receive FIFO Watermark */
143 #define FCTR_RFWM_1	0x00000000 /*  Transfer Request when 1 valid stages */
144 #define FCTR_RFWM_4	0x00002000 /*  Transfer Request when 4 valid stages */
145 #define FCTR_RFWM_8	0x00004000 /*  Transfer Request when 8 valid stages */
146 #define FCTR_RFWM_16	0x00006000 /*  Transfer Request when 16 valid stages */
147 #define FCTR_RFWM_32	0x00008000 /*  Transfer Request when 32 valid stages */
148 #define FCTR_RFWM_64	0x0000a000 /*  Transfer Request when 64 valid stages */
149 #define FCTR_RFWM_128	0x0000c000 /*  Transfer Request when 128 valid stages */
150 #define FCTR_RFWM_256	0x0000e000 /*  Transfer Request when 256 valid stages */
151 #define FCTR_RFUA_MASK	0x00001ff0 /* Receive FIFO Usable Area (0x40 = full) */
152 #define FCTR_RFUA_SHIFT		 4
153 #define FCTR_RFUA(i)	((i) << FCTR_RFUA_SHIFT)
154 
155 /* STR */
156 #define STR_TFEMP	0x20000000 /* Transmit FIFO Empty */
157 #define STR_TDREQ	0x10000000 /* Transmit Data Transfer Request */
158 #define STR_TEOF	0x00800000 /* Frame Transmission End */
159 #define STR_TFSERR	0x00200000 /* Transmit Frame Synchronization Error */
160 #define STR_TFOVF	0x00100000 /* Transmit FIFO Overflow */
161 #define STR_TFUDF	0x00080000 /* Transmit FIFO Underflow */
162 #define STR_RFFUL	0x00002000 /* Receive FIFO Full */
163 #define STR_RDREQ	0x00001000 /* Receive Data Transfer Request */
164 #define STR_REOF	0x00000080 /* Frame Reception End */
165 #define STR_RFSERR	0x00000020 /* Receive Frame Synchronization Error */
166 #define STR_RFUDF	0x00000010 /* Receive FIFO Underflow */
167 #define STR_RFOVF	0x00000008 /* Receive FIFO Overflow */
168 
169 /* IER */
170 #define IER_TDMAE	0x80000000 /* Transmit Data DMA Transfer Req. Enable */
171 #define IER_TFEMPE	0x20000000 /* Transmit FIFO Empty Enable */
172 #define IER_TDREQE	0x10000000 /* Transmit Data Transfer Request Enable */
173 #define IER_TEOFE	0x00800000 /* Frame Transmission End Enable */
174 #define IER_TFSERRE	0x00200000 /* Transmit Frame Sync Error Enable */
175 #define IER_TFOVFE	0x00100000 /* Transmit FIFO Overflow Enable */
176 #define IER_TFUDFE	0x00080000 /* Transmit FIFO Underflow Enable */
177 #define IER_RDMAE	0x00008000 /* Receive Data DMA Transfer Req. Enable */
178 #define IER_RFFULE	0x00002000 /* Receive FIFO Full Enable */
179 #define IER_RDREQE	0x00001000 /* Receive Data Transfer Request Enable */
180 #define IER_REOFE	0x00000080 /* Frame Reception End Enable */
181 #define IER_RFSERRE	0x00000020 /* Receive Frame Sync Error Enable */
182 #define IER_RFUDFE	0x00000010 /* Receive FIFO Underflow Enable */
183 #define IER_RFOVFE	0x00000008 /* Receive FIFO Overflow Enable */
184 
185 
186 static u32 sh_msiof_read(struct sh_msiof_spi_priv *p, int reg_offs)
187 {
188 	switch (reg_offs) {
189 	case TSCR:
190 	case RSCR:
191 		return ioread16(p->mapbase + reg_offs);
192 	default:
193 		return ioread32(p->mapbase + reg_offs);
194 	}
195 }
196 
197 static void sh_msiof_write(struct sh_msiof_spi_priv *p, int reg_offs,
198 			   u32 value)
199 {
200 	switch (reg_offs) {
201 	case TSCR:
202 	case RSCR:
203 		iowrite16(value, p->mapbase + reg_offs);
204 		break;
205 	default:
206 		iowrite32(value, p->mapbase + reg_offs);
207 		break;
208 	}
209 }
210 
211 static int sh_msiof_modify_ctr_wait(struct sh_msiof_spi_priv *p,
212 				    u32 clr, u32 set)
213 {
214 	u32 mask = clr | set;
215 	u32 data;
216 	int k;
217 
218 	data = sh_msiof_read(p, CTR);
219 	data &= ~clr;
220 	data |= set;
221 	sh_msiof_write(p, CTR, data);
222 
223 	for (k = 100; k > 0; k--) {
224 		if ((sh_msiof_read(p, CTR) & mask) == set)
225 			break;
226 
227 		udelay(10);
228 	}
229 
230 	return k > 0 ? 0 : -ETIMEDOUT;
231 }
232 
233 static irqreturn_t sh_msiof_spi_irq(int irq, void *data)
234 {
235 	struct sh_msiof_spi_priv *p = data;
236 
237 	/* just disable the interrupt and wake up */
238 	sh_msiof_write(p, IER, 0);
239 	complete(&p->done);
240 
241 	return IRQ_HANDLED;
242 }
243 
244 static struct {
245 	unsigned short div;
246 	unsigned short brdv;
247 } const sh_msiof_spi_div_table[] = {
248 	{ 1,	SCR_BRDV_DIV_1 },
249 	{ 2,	SCR_BRDV_DIV_2 },
250 	{ 4,	SCR_BRDV_DIV_4 },
251 	{ 8,	SCR_BRDV_DIV_8 },
252 	{ 16,	SCR_BRDV_DIV_16 },
253 	{ 32,	SCR_BRDV_DIV_32 },
254 };
255 
256 static void sh_msiof_spi_set_clk_regs(struct sh_msiof_spi_priv *p,
257 				      unsigned long parent_rate, u32 spi_hz)
258 {
259 	unsigned long div = 1024;
260 	u32 brps, scr;
261 	size_t k;
262 
263 	if (!WARN_ON(!spi_hz || !parent_rate))
264 		div = DIV_ROUND_UP(parent_rate, spi_hz);
265 
266 	for (k = 0; k < ARRAY_SIZE(sh_msiof_spi_div_table); k++) {
267 		brps = DIV_ROUND_UP(div, sh_msiof_spi_div_table[k].div);
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->chipdata->master_flags & SPI_MASTER_MUST_TX))
277 		sh_msiof_write(p, RSCR, scr);
278 }
279 
280 static 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 
297 static 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 
322 static 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->chipdata->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 
359 static 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->chipdata->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 
374 static 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 
379 static 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 
389 static 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 
399 static 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 
409 static 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 
419 static 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 
429 static 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 
439 static 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 
449 static 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 
459 static 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 
469 static 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 
479 static 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 
489 static 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 
499 static 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 
509 static 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 
519 static 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 
550 static 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 
565 static 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 
583 static 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 
599 static 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 
660 stop_reset:
661 	sh_msiof_reset_str(p);
662 	sh_msiof_spi_stop(p, rx_buf);
663 stop_ier:
664 	sh_msiof_write(p, IER, 0);
665 	return ret;
666 }
667 
668 static 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 
676 static 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 
771 stop_reset:
772 	sh_msiof_reset_str(p);
773 	sh_msiof_spi_stop(p, rx);
774 stop_dma:
775 	if (tx)
776 		dmaengine_terminate_all(p->master->dma_tx);
777 no_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 
784 static 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 
803 static 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 
822 static void copy_plain32(u32 *dst, const u32 *src, unsigned int words)
823 {
824 	memcpy(dst, src, words * 4);
825 }
826 
827 static 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 = min(len, MAX_WDLEN * 4);
854 
855 		if (bits <= 8) {
856 			if (l & 3)
857 				break;
858 			copy32 = copy_bswap32;
859 		} else if (bits <= 16) {
860 			if (l & 1)
861 				break;
862 			copy32 = copy_wswap32;
863 		} else {
864 			copy32 = copy_plain32;
865 		}
866 
867 		if (tx_buf)
868 			copy32(p->tx_dma_page, tx_buf, l / 4);
869 
870 		ret = sh_msiof_dma_once(p, tx_buf, rx_buf, l);
871 		if (ret == -EAGAIN) {
872 			pr_warn_once("%s %s: DMA not available, falling back to PIO\n",
873 				     dev_driver_string(&p->pdev->dev),
874 				     dev_name(&p->pdev->dev));
875 			break;
876 		}
877 		if (ret)
878 			return ret;
879 
880 		if (rx_buf) {
881 			copy32(rx_buf, p->rx_dma_page, l / 4);
882 			rx_buf += l;
883 		}
884 		if (tx_buf)
885 			tx_buf += l;
886 
887 		len -= l;
888 		if (!len)
889 			return 0;
890 	}
891 
892 	if (bits <= 8 && len > 15 && !(len & 3)) {
893 		bits = 32;
894 		swab = true;
895 	} else {
896 		swab = false;
897 	}
898 
899 	/* setup bytes per word and fifo read/write functions */
900 	if (bits <= 8) {
901 		bytes_per_word = 1;
902 		tx_fifo = sh_msiof_spi_write_fifo_8;
903 		rx_fifo = sh_msiof_spi_read_fifo_8;
904 	} else if (bits <= 16) {
905 		bytes_per_word = 2;
906 		if ((unsigned long)tx_buf & 0x01)
907 			tx_fifo = sh_msiof_spi_write_fifo_16u;
908 		else
909 			tx_fifo = sh_msiof_spi_write_fifo_16;
910 
911 		if ((unsigned long)rx_buf & 0x01)
912 			rx_fifo = sh_msiof_spi_read_fifo_16u;
913 		else
914 			rx_fifo = sh_msiof_spi_read_fifo_16;
915 	} else if (swab) {
916 		bytes_per_word = 4;
917 		if ((unsigned long)tx_buf & 0x03)
918 			tx_fifo = sh_msiof_spi_write_fifo_s32u;
919 		else
920 			tx_fifo = sh_msiof_spi_write_fifo_s32;
921 
922 		if ((unsigned long)rx_buf & 0x03)
923 			rx_fifo = sh_msiof_spi_read_fifo_s32u;
924 		else
925 			rx_fifo = sh_msiof_spi_read_fifo_s32;
926 	} else {
927 		bytes_per_word = 4;
928 		if ((unsigned long)tx_buf & 0x03)
929 			tx_fifo = sh_msiof_spi_write_fifo_32u;
930 		else
931 			tx_fifo = sh_msiof_spi_write_fifo_32;
932 
933 		if ((unsigned long)rx_buf & 0x03)
934 			rx_fifo = sh_msiof_spi_read_fifo_32u;
935 		else
936 			rx_fifo = sh_msiof_spi_read_fifo_32;
937 	}
938 
939 	/* transfer in fifo sized chunks */
940 	words = len / bytes_per_word;
941 
942 	while (words > 0) {
943 		n = sh_msiof_spi_txrx_once(p, tx_fifo, rx_fifo, tx_buf, rx_buf,
944 					   words, bits);
945 		if (n < 0)
946 			return n;
947 
948 		if (tx_buf)
949 			tx_buf += n * bytes_per_word;
950 		if (rx_buf)
951 			rx_buf += n * bytes_per_word;
952 		words -= n;
953 	}
954 
955 	return 0;
956 }
957 
958 static const struct sh_msiof_chipdata sh_data = {
959 	.tx_fifo_size = 64,
960 	.rx_fifo_size = 64,
961 	.master_flags = 0,
962 };
963 
964 static const struct sh_msiof_chipdata r8a779x_data = {
965 	.tx_fifo_size = 64,
966 	.rx_fifo_size = 256,
967 	.master_flags = SPI_MASTER_MUST_TX,
968 };
969 
970 static const struct of_device_id sh_msiof_match[] = {
971 	{ .compatible = "renesas,sh-msiof",        .data = &sh_data },
972 	{ .compatible = "renesas,sh-mobile-msiof", .data = &sh_data },
973 	{ .compatible = "renesas,msiof-r8a7790",   .data = &r8a779x_data },
974 	{ .compatible = "renesas,msiof-r8a7791",   .data = &r8a779x_data },
975 	{ .compatible = "renesas,msiof-r8a7792",   .data = &r8a779x_data },
976 	{ .compatible = "renesas,msiof-r8a7793",   .data = &r8a779x_data },
977 	{ .compatible = "renesas,msiof-r8a7794",   .data = &r8a779x_data },
978 	{},
979 };
980 MODULE_DEVICE_TABLE(of, sh_msiof_match);
981 
982 #ifdef CONFIG_OF
983 static struct sh_msiof_spi_info *sh_msiof_spi_parse_dt(struct device *dev)
984 {
985 	struct sh_msiof_spi_info *info;
986 	struct device_node *np = dev->of_node;
987 	u32 num_cs = 1;
988 
989 	info = devm_kzalloc(dev, sizeof(struct sh_msiof_spi_info), GFP_KERNEL);
990 	if (!info)
991 		return NULL;
992 
993 	/* Parse the MSIOF properties */
994 	of_property_read_u32(np, "num-cs", &num_cs);
995 	of_property_read_u32(np, "renesas,tx-fifo-size",
996 					&info->tx_fifo_override);
997 	of_property_read_u32(np, "renesas,rx-fifo-size",
998 					&info->rx_fifo_override);
999 	of_property_read_u32(np, "renesas,dtdl", &info->dtdl);
1000 	of_property_read_u32(np, "renesas,syncdl", &info->syncdl);
1001 
1002 	info->num_chipselect = num_cs;
1003 
1004 	return info;
1005 }
1006 #else
1007 static struct sh_msiof_spi_info *sh_msiof_spi_parse_dt(struct device *dev)
1008 {
1009 	return NULL;
1010 }
1011 #endif
1012 
1013 static struct dma_chan *sh_msiof_request_dma_chan(struct device *dev,
1014 	enum dma_transfer_direction dir, unsigned int id, dma_addr_t port_addr)
1015 {
1016 	dma_cap_mask_t mask;
1017 	struct dma_chan *chan;
1018 	struct dma_slave_config cfg;
1019 	int ret;
1020 
1021 	dma_cap_zero(mask);
1022 	dma_cap_set(DMA_SLAVE, mask);
1023 
1024 	chan = dma_request_slave_channel_compat(mask, shdma_chan_filter,
1025 				(void *)(unsigned long)id, dev,
1026 				dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1027 	if (!chan) {
1028 		dev_warn(dev, "dma_request_slave_channel_compat failed\n");
1029 		return NULL;
1030 	}
1031 
1032 	memset(&cfg, 0, sizeof(cfg));
1033 	cfg.direction = dir;
1034 	if (dir == DMA_MEM_TO_DEV) {
1035 		cfg.dst_addr = port_addr;
1036 		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1037 	} else {
1038 		cfg.src_addr = port_addr;
1039 		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1040 	}
1041 
1042 	ret = dmaengine_slave_config(chan, &cfg);
1043 	if (ret) {
1044 		dev_warn(dev, "dmaengine_slave_config failed %d\n", ret);
1045 		dma_release_channel(chan);
1046 		return NULL;
1047 	}
1048 
1049 	return chan;
1050 }
1051 
1052 static int sh_msiof_request_dma(struct sh_msiof_spi_priv *p)
1053 {
1054 	struct platform_device *pdev = p->pdev;
1055 	struct device *dev = &pdev->dev;
1056 	const struct sh_msiof_spi_info *info = dev_get_platdata(dev);
1057 	unsigned int dma_tx_id, dma_rx_id;
1058 	const struct resource *res;
1059 	struct spi_master *master;
1060 	struct device *tx_dev, *rx_dev;
1061 
1062 	if (dev->of_node) {
1063 		/* In the OF case we will get the slave IDs from the DT */
1064 		dma_tx_id = 0;
1065 		dma_rx_id = 0;
1066 	} else if (info && info->dma_tx_id && info->dma_rx_id) {
1067 		dma_tx_id = info->dma_tx_id;
1068 		dma_rx_id = info->dma_rx_id;
1069 	} else {
1070 		/* The driver assumes no error */
1071 		return 0;
1072 	}
1073 
1074 	/* The DMA engine uses the second register set, if present */
1075 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1076 	if (!res)
1077 		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1078 
1079 	master = p->master;
1080 	master->dma_tx = sh_msiof_request_dma_chan(dev, DMA_MEM_TO_DEV,
1081 						   dma_tx_id,
1082 						   res->start + TFDR);
1083 	if (!master->dma_tx)
1084 		return -ENODEV;
1085 
1086 	master->dma_rx = sh_msiof_request_dma_chan(dev, DMA_DEV_TO_MEM,
1087 						   dma_rx_id,
1088 						   res->start + RFDR);
1089 	if (!master->dma_rx)
1090 		goto free_tx_chan;
1091 
1092 	p->tx_dma_page = (void *)__get_free_page(GFP_KERNEL | GFP_DMA);
1093 	if (!p->tx_dma_page)
1094 		goto free_rx_chan;
1095 
1096 	p->rx_dma_page = (void *)__get_free_page(GFP_KERNEL | GFP_DMA);
1097 	if (!p->rx_dma_page)
1098 		goto free_tx_page;
1099 
1100 	tx_dev = master->dma_tx->device->dev;
1101 	p->tx_dma_addr = dma_map_single(tx_dev, p->tx_dma_page, PAGE_SIZE,
1102 					DMA_TO_DEVICE);
1103 	if (dma_mapping_error(tx_dev, p->tx_dma_addr))
1104 		goto free_rx_page;
1105 
1106 	rx_dev = master->dma_rx->device->dev;
1107 	p->rx_dma_addr = dma_map_single(rx_dev, p->rx_dma_page, PAGE_SIZE,
1108 					DMA_FROM_DEVICE);
1109 	if (dma_mapping_error(rx_dev, p->rx_dma_addr))
1110 		goto unmap_tx_page;
1111 
1112 	dev_info(dev, "DMA available");
1113 	return 0;
1114 
1115 unmap_tx_page:
1116 	dma_unmap_single(tx_dev, p->tx_dma_addr, PAGE_SIZE, DMA_TO_DEVICE);
1117 free_rx_page:
1118 	free_page((unsigned long)p->rx_dma_page);
1119 free_tx_page:
1120 	free_page((unsigned long)p->tx_dma_page);
1121 free_rx_chan:
1122 	dma_release_channel(master->dma_rx);
1123 free_tx_chan:
1124 	dma_release_channel(master->dma_tx);
1125 	master->dma_tx = NULL;
1126 	return -ENODEV;
1127 }
1128 
1129 static void sh_msiof_release_dma(struct sh_msiof_spi_priv *p)
1130 {
1131 	struct spi_master *master = p->master;
1132 	struct device *dev;
1133 
1134 	if (!master->dma_tx)
1135 		return;
1136 
1137 	dev = &p->pdev->dev;
1138 	dma_unmap_single(master->dma_rx->device->dev, p->rx_dma_addr,
1139 			 PAGE_SIZE, DMA_FROM_DEVICE);
1140 	dma_unmap_single(master->dma_tx->device->dev, p->tx_dma_addr,
1141 			 PAGE_SIZE, DMA_TO_DEVICE);
1142 	free_page((unsigned long)p->rx_dma_page);
1143 	free_page((unsigned long)p->tx_dma_page);
1144 	dma_release_channel(master->dma_rx);
1145 	dma_release_channel(master->dma_tx);
1146 }
1147 
1148 static int sh_msiof_spi_probe(struct platform_device *pdev)
1149 {
1150 	struct resource	*r;
1151 	struct spi_master *master;
1152 	const struct of_device_id *of_id;
1153 	struct sh_msiof_spi_priv *p;
1154 	int i;
1155 	int ret;
1156 
1157 	master = spi_alloc_master(&pdev->dev, sizeof(struct sh_msiof_spi_priv));
1158 	if (master == NULL) {
1159 		dev_err(&pdev->dev, "failed to allocate spi master\n");
1160 		return -ENOMEM;
1161 	}
1162 
1163 	p = spi_master_get_devdata(master);
1164 
1165 	platform_set_drvdata(pdev, p);
1166 	p->master = master;
1167 
1168 	of_id = of_match_device(sh_msiof_match, &pdev->dev);
1169 	if (of_id) {
1170 		p->chipdata = of_id->data;
1171 		p->info = sh_msiof_spi_parse_dt(&pdev->dev);
1172 	} else {
1173 		p->chipdata = (const void *)pdev->id_entry->driver_data;
1174 		p->info = dev_get_platdata(&pdev->dev);
1175 	}
1176 
1177 	if (!p->info) {
1178 		dev_err(&pdev->dev, "failed to obtain device info\n");
1179 		ret = -ENXIO;
1180 		goto err1;
1181 	}
1182 
1183 	init_completion(&p->done);
1184 
1185 	p->clk = devm_clk_get(&pdev->dev, NULL);
1186 	if (IS_ERR(p->clk)) {
1187 		dev_err(&pdev->dev, "cannot get clock\n");
1188 		ret = PTR_ERR(p->clk);
1189 		goto err1;
1190 	}
1191 
1192 	i = platform_get_irq(pdev, 0);
1193 	if (i < 0) {
1194 		dev_err(&pdev->dev, "cannot get platform IRQ\n");
1195 		ret = -ENOENT;
1196 		goto err1;
1197 	}
1198 
1199 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1200 	p->mapbase = devm_ioremap_resource(&pdev->dev, r);
1201 	if (IS_ERR(p->mapbase)) {
1202 		ret = PTR_ERR(p->mapbase);
1203 		goto err1;
1204 	}
1205 
1206 	ret = devm_request_irq(&pdev->dev, i, sh_msiof_spi_irq, 0,
1207 			       dev_name(&pdev->dev), p);
1208 	if (ret) {
1209 		dev_err(&pdev->dev, "unable to request irq\n");
1210 		goto err1;
1211 	}
1212 
1213 	p->pdev = pdev;
1214 	pm_runtime_enable(&pdev->dev);
1215 
1216 	/* Platform data may override FIFO sizes */
1217 	p->tx_fifo_size = p->chipdata->tx_fifo_size;
1218 	p->rx_fifo_size = p->chipdata->rx_fifo_size;
1219 	if (p->info->tx_fifo_override)
1220 		p->tx_fifo_size = p->info->tx_fifo_override;
1221 	if (p->info->rx_fifo_override)
1222 		p->rx_fifo_size = p->info->rx_fifo_override;
1223 
1224 	/* init master code */
1225 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1226 	master->mode_bits |= SPI_LSB_FIRST | SPI_3WIRE;
1227 	master->flags = p->chipdata->master_flags;
1228 	master->bus_num = pdev->id;
1229 	master->dev.of_node = pdev->dev.of_node;
1230 	master->num_chipselect = p->info->num_chipselect;
1231 	master->setup = sh_msiof_spi_setup;
1232 	master->prepare_message = sh_msiof_prepare_message;
1233 	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 32);
1234 	master->auto_runtime_pm = true;
1235 	master->transfer_one = sh_msiof_transfer_one;
1236 
1237 	ret = sh_msiof_request_dma(p);
1238 	if (ret < 0)
1239 		dev_warn(&pdev->dev, "DMA not available, using PIO\n");
1240 
1241 	ret = devm_spi_register_master(&pdev->dev, master);
1242 	if (ret < 0) {
1243 		dev_err(&pdev->dev, "spi_register_master error.\n");
1244 		goto err2;
1245 	}
1246 
1247 	return 0;
1248 
1249  err2:
1250 	sh_msiof_release_dma(p);
1251 	pm_runtime_disable(&pdev->dev);
1252  err1:
1253 	spi_master_put(master);
1254 	return ret;
1255 }
1256 
1257 static int sh_msiof_spi_remove(struct platform_device *pdev)
1258 {
1259 	struct sh_msiof_spi_priv *p = platform_get_drvdata(pdev);
1260 
1261 	sh_msiof_release_dma(p);
1262 	pm_runtime_disable(&pdev->dev);
1263 	return 0;
1264 }
1265 
1266 static const struct platform_device_id spi_driver_ids[] = {
1267 	{ "spi_sh_msiof",	(kernel_ulong_t)&sh_data },
1268 	{ "spi_r8a7790_msiof",	(kernel_ulong_t)&r8a779x_data },
1269 	{ "spi_r8a7791_msiof",	(kernel_ulong_t)&r8a779x_data },
1270 	{ "spi_r8a7792_msiof",	(kernel_ulong_t)&r8a779x_data },
1271 	{ "spi_r8a7793_msiof",	(kernel_ulong_t)&r8a779x_data },
1272 	{ "spi_r8a7794_msiof",	(kernel_ulong_t)&r8a779x_data },
1273 	{},
1274 };
1275 MODULE_DEVICE_TABLE(platform, spi_driver_ids);
1276 
1277 static struct platform_driver sh_msiof_spi_drv = {
1278 	.probe		= sh_msiof_spi_probe,
1279 	.remove		= sh_msiof_spi_remove,
1280 	.id_table	= spi_driver_ids,
1281 	.driver		= {
1282 		.name		= "spi_sh_msiof",
1283 		.of_match_table = of_match_ptr(sh_msiof_match),
1284 	},
1285 };
1286 module_platform_driver(sh_msiof_spi_drv);
1287 
1288 MODULE_DESCRIPTION("SuperH MSIOF SPI Master Interface Driver");
1289 MODULE_AUTHOR("Magnus Damm");
1290 MODULE_LICENSE("GPL v2");
1291 MODULE_ALIAS("platform:spi_sh_msiof");
1292