xref: /openbmc/linux/drivers/spi/spi-sh-msiof.c (revision b285d2ae)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * SuperH MSIOF SPI Controller Interface
4  *
5  * Copyright (c) 2009 Magnus Damm
6  * Copyright (C) 2014 Renesas Electronics Corporation
7  * Copyright (C) 2014-2017 Glider bvba
8  */
9 
10 #include <linux/bitmap.h>
11 #include <linux/clk.h>
12 #include <linux/completion.h>
13 #include <linux/delay.h>
14 #include <linux/dma-mapping.h>
15 #include <linux/dmaengine.h>
16 #include <linux/err.h>
17 #include <linux/interrupt.h>
18 #include <linux/io.h>
19 #include <linux/iopoll.h>
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/of.h>
23 #include <linux/of_device.h>
24 #include <linux/platform_device.h>
25 #include <linux/pm_runtime.h>
26 #include <linux/sh_dma.h>
27 
28 #include <linux/spi/sh_msiof.h>
29 #include <linux/spi/spi.h>
30 
31 #include <asm/unaligned.h>
32 
33 struct sh_msiof_chipdata {
34 	u32 bits_per_word_mask;
35 	u16 tx_fifo_size;
36 	u16 rx_fifo_size;
37 	u16 ctlr_flags;
38 	u16 min_div_pow;
39 };
40 
41 struct sh_msiof_spi_priv {
42 	struct spi_controller *ctlr;
43 	void __iomem *mapbase;
44 	struct clk *clk;
45 	struct platform_device *pdev;
46 	struct sh_msiof_spi_info *info;
47 	struct completion done;
48 	struct completion done_txdma;
49 	unsigned int tx_fifo_size;
50 	unsigned int rx_fifo_size;
51 	unsigned int min_div_pow;
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 	bool native_cs_inited;
57 	bool native_cs_high;
58 	bool slave_aborted;
59 };
60 
61 #define MAX_SS	3	/* Maximum number of native chip selects */
62 
63 #define SITMDR1	0x00	/* Transmit Mode Register 1 */
64 #define SITMDR2	0x04	/* Transmit Mode Register 2 */
65 #define SITMDR3	0x08	/* Transmit Mode Register 3 */
66 #define SIRMDR1	0x10	/* Receive Mode Register 1 */
67 #define SIRMDR2	0x14	/* Receive Mode Register 2 */
68 #define SIRMDR3	0x18	/* Receive Mode Register 3 */
69 #define SITSCR	0x20	/* Transmit Clock Select Register */
70 #define SIRSCR	0x22	/* Receive Clock Select Register (SH, A1, APE6) */
71 #define SICTR	0x28	/* Control Register */
72 #define SIFCTR	0x30	/* FIFO Control Register */
73 #define SISTR	0x40	/* Status Register */
74 #define SIIER	0x44	/* Interrupt Enable Register */
75 #define SITDR1	0x48	/* Transmit Control Data Register 1 (SH, A1) */
76 #define SITDR2	0x4c	/* Transmit Control Data Register 2 (SH, A1) */
77 #define SITFDR	0x50	/* Transmit FIFO Data Register */
78 #define SIRDR1	0x58	/* Receive Control Data Register 1 (SH, A1) */
79 #define SIRDR2	0x5c	/* Receive Control Data Register 2 (SH, A1) */
80 #define SIRFDR	0x60	/* Receive FIFO Data Register */
81 
82 /* SITMDR1 and SIRMDR1 */
83 #define SIMDR1_TRMD		BIT(31)		/* Transfer Mode (1 = Master mode) */
84 #define SIMDR1_SYNCMD_MASK	GENMASK(29, 28)	/* SYNC Mode */
85 #define SIMDR1_SYNCMD_SPI	(2 << 28)	/*   Level mode/SPI */
86 #define SIMDR1_SYNCMD_LR	(3 << 28)	/*   L/R mode */
87 #define SIMDR1_SYNCAC_SHIFT	25		/* Sync Polarity (1 = Active-low) */
88 #define SIMDR1_BITLSB_SHIFT	24		/* MSB/LSB First (1 = LSB first) */
89 #define SIMDR1_DTDL_SHIFT	20		/* Data Pin Bit Delay for MSIOF_SYNC */
90 #define SIMDR1_SYNCDL_SHIFT	16		/* Frame Sync Signal Timing Delay */
91 #define SIMDR1_FLD_MASK		GENMASK(3, 2)	/* Frame Sync Signal Interval (0-3) */
92 #define SIMDR1_FLD_SHIFT	2
93 #define SIMDR1_XXSTP		BIT(0)		/* Transmission/Reception Stop on FIFO */
94 /* SITMDR1 */
95 #define SITMDR1_PCON		BIT(30)		/* Transfer Signal Connection */
96 #define SITMDR1_SYNCCH_MASK	GENMASK(27, 26)	/* Sync Signal Channel Select */
97 #define SITMDR1_SYNCCH_SHIFT	26		/* 0=MSIOF_SYNC, 1=MSIOF_SS1, 2=MSIOF_SS2 */
98 
99 /* SITMDR2 and SIRMDR2 */
100 #define SIMDR2_BITLEN1(i)	(((i) - 1) << 24) /* Data Size (8-32 bits) */
101 #define SIMDR2_WDLEN1(i)	(((i) - 1) << 16) /* Word Count (1-64/256 (SH, A1))) */
102 #define SIMDR2_GRPMASK1		BIT(0)		/* Group Output Mask 1 (SH, A1) */
103 
104 /* SITSCR and SIRSCR */
105 #define SISCR_BRPS_MASK		GENMASK(12, 8)	/* Prescaler Setting (1-32) */
106 #define SISCR_BRPS(i)		(((i) - 1) << 8)
107 #define SISCR_BRDV_MASK		GENMASK(2, 0)	/* Baud Rate Generator's Division Ratio */
108 #define SISCR_BRDV_DIV_2	0
109 #define SISCR_BRDV_DIV_4	1
110 #define SISCR_BRDV_DIV_8	2
111 #define SISCR_BRDV_DIV_16	3
112 #define SISCR_BRDV_DIV_32	4
113 #define SISCR_BRDV_DIV_1	7
114 
115 /* SICTR */
116 #define SICTR_TSCKIZ_MASK	GENMASK(31, 30)	/* Transmit Clock I/O Polarity Select */
117 #define SICTR_TSCKIZ_SCK	BIT(31)		/*   Disable SCK when TX disabled */
118 #define SICTR_TSCKIZ_POL_SHIFT	30		/*   Transmit Clock Polarity */
119 #define SICTR_RSCKIZ_MASK	GENMASK(29, 28) /* Receive Clock Polarity Select */
120 #define SICTR_RSCKIZ_SCK	BIT(29)		/*   Must match CTR_TSCKIZ_SCK */
121 #define SICTR_RSCKIZ_POL_SHIFT	28		/*   Receive Clock Polarity */
122 #define SICTR_TEDG_SHIFT	27		/* Transmit Timing (1 = falling edge) */
123 #define SICTR_REDG_SHIFT	26		/* Receive Timing (1 = falling edge) */
124 #define SICTR_TXDIZ_MASK	GENMASK(23, 22)	/* Pin Output When TX is Disabled */
125 #define SICTR_TXDIZ_LOW		(0 << 22)	/*   0 */
126 #define SICTR_TXDIZ_HIGH	(1 << 22)	/*   1 */
127 #define SICTR_TXDIZ_HIZ		(2 << 22)	/*   High-impedance */
128 #define SICTR_TSCKE		BIT(15)		/* Transmit Serial Clock Output Enable */
129 #define SICTR_TFSE		BIT(14)		/* Transmit Frame Sync Signal Output Enable */
130 #define SICTR_TXE		BIT(9)		/* Transmit Enable */
131 #define SICTR_RXE		BIT(8)		/* Receive Enable */
132 #define SICTR_TXRST		BIT(1)		/* Transmit Reset */
133 #define SICTR_RXRST		BIT(0)		/* Receive Reset */
134 
135 /* SIFCTR */
136 #define SIFCTR_TFWM_MASK	GENMASK(31, 29)	/* Transmit FIFO Watermark */
137 #define SIFCTR_TFWM_64		(0 << 29)	/*  Transfer Request when 64 empty stages */
138 #define SIFCTR_TFWM_32		(1 << 29)	/*  Transfer Request when 32 empty stages */
139 #define SIFCTR_TFWM_24		(2 << 29)	/*  Transfer Request when 24 empty stages */
140 #define SIFCTR_TFWM_16		(3 << 29)	/*  Transfer Request when 16 empty stages */
141 #define SIFCTR_TFWM_12		(4 << 29)	/*  Transfer Request when 12 empty stages */
142 #define SIFCTR_TFWM_8		(5 << 29)	/*  Transfer Request when 8 empty stages */
143 #define SIFCTR_TFWM_4		(6 << 29)	/*  Transfer Request when 4 empty stages */
144 #define SIFCTR_TFWM_1		(7 << 29)	/*  Transfer Request when 1 empty stage */
145 #define SIFCTR_TFUA_MASK	GENMASK(26, 20) /* Transmit FIFO Usable Area */
146 #define SIFCTR_TFUA_SHIFT	20
147 #define SIFCTR_TFUA(i)		((i) << SIFCTR_TFUA_SHIFT)
148 #define SIFCTR_RFWM_MASK	GENMASK(15, 13)	/* Receive FIFO Watermark */
149 #define SIFCTR_RFWM_1		(0 << 13)	/*  Transfer Request when 1 valid stages */
150 #define SIFCTR_RFWM_4		(1 << 13)	/*  Transfer Request when 4 valid stages */
151 #define SIFCTR_RFWM_8		(2 << 13)	/*  Transfer Request when 8 valid stages */
152 #define SIFCTR_RFWM_16		(3 << 13)	/*  Transfer Request when 16 valid stages */
153 #define SIFCTR_RFWM_32		(4 << 13)	/*  Transfer Request when 32 valid stages */
154 #define SIFCTR_RFWM_64		(5 << 13)	/*  Transfer Request when 64 valid stages */
155 #define SIFCTR_RFWM_128		(6 << 13)	/*  Transfer Request when 128 valid stages */
156 #define SIFCTR_RFWM_256		(7 << 13)	/*  Transfer Request when 256 valid stages */
157 #define SIFCTR_RFUA_MASK	GENMASK(12, 4)	/* Receive FIFO Usable Area (0x40 = full) */
158 #define SIFCTR_RFUA_SHIFT	4
159 #define SIFCTR_RFUA(i)		((i) << SIFCTR_RFUA_SHIFT)
160 
161 /* SISTR */
162 #define SISTR_TFEMP		BIT(29) /* Transmit FIFO Empty */
163 #define SISTR_TDREQ		BIT(28) /* Transmit Data Transfer Request */
164 #define SISTR_TEOF		BIT(23) /* Frame Transmission End */
165 #define SISTR_TFSERR		BIT(21) /* Transmit Frame Synchronization Error */
166 #define SISTR_TFOVF		BIT(20) /* Transmit FIFO Overflow */
167 #define SISTR_TFUDF		BIT(19) /* Transmit FIFO Underflow */
168 #define SISTR_RFFUL		BIT(13) /* Receive FIFO Full */
169 #define SISTR_RDREQ		BIT(12) /* Receive Data Transfer Request */
170 #define SISTR_REOF		BIT(7)  /* Frame Reception End */
171 #define SISTR_RFSERR		BIT(5)  /* Receive Frame Synchronization Error */
172 #define SISTR_RFUDF		BIT(4)  /* Receive FIFO Underflow */
173 #define SISTR_RFOVF		BIT(3)  /* Receive FIFO Overflow */
174 
175 /* SIIER */
176 #define SIIER_TDMAE		BIT(31) /* Transmit Data DMA Transfer Req. Enable */
177 #define SIIER_TFEMPE		BIT(29) /* Transmit FIFO Empty Enable */
178 #define SIIER_TDREQE		BIT(28) /* Transmit Data Transfer Request Enable */
179 #define SIIER_TEOFE		BIT(23) /* Frame Transmission End Enable */
180 #define SIIER_TFSERRE		BIT(21) /* Transmit Frame Sync Error Enable */
181 #define SIIER_TFOVFE		BIT(20) /* Transmit FIFO Overflow Enable */
182 #define SIIER_TFUDFE		BIT(19) /* Transmit FIFO Underflow Enable */
183 #define SIIER_RDMAE		BIT(15) /* Receive Data DMA Transfer Req. Enable */
184 #define SIIER_RFFULE		BIT(13) /* Receive FIFO Full Enable */
185 #define SIIER_RDREQE		BIT(12) /* Receive Data Transfer Request Enable */
186 #define SIIER_REOFE		BIT(7)  /* Frame Reception End Enable */
187 #define SIIER_RFSERRE		BIT(5)  /* Receive Frame Sync Error Enable */
188 #define SIIER_RFUDFE		BIT(4)  /* Receive FIFO Underflow Enable */
189 #define SIIER_RFOVFE		BIT(3)  /* Receive FIFO Overflow Enable */
190 
191 
192 static u32 sh_msiof_read(struct sh_msiof_spi_priv *p, int reg_offs)
193 {
194 	switch (reg_offs) {
195 	case SITSCR:
196 	case SIRSCR:
197 		return ioread16(p->mapbase + reg_offs);
198 	default:
199 		return ioread32(p->mapbase + reg_offs);
200 	}
201 }
202 
203 static void sh_msiof_write(struct sh_msiof_spi_priv *p, int reg_offs,
204 			   u32 value)
205 {
206 	switch (reg_offs) {
207 	case SITSCR:
208 	case SIRSCR:
209 		iowrite16(value, p->mapbase + reg_offs);
210 		break;
211 	default:
212 		iowrite32(value, p->mapbase + reg_offs);
213 		break;
214 	}
215 }
216 
217 static int sh_msiof_modify_ctr_wait(struct sh_msiof_spi_priv *p,
218 				    u32 clr, u32 set)
219 {
220 	u32 mask = clr | set;
221 	u32 data;
222 
223 	data = sh_msiof_read(p, SICTR);
224 	data &= ~clr;
225 	data |= set;
226 	sh_msiof_write(p, SICTR, data);
227 
228 	return readl_poll_timeout_atomic(p->mapbase + SICTR, data,
229 					 (data & mask) == set, 1, 100);
230 }
231 
232 static irqreturn_t sh_msiof_spi_irq(int irq, void *data)
233 {
234 	struct sh_msiof_spi_priv *p = data;
235 
236 	/* just disable the interrupt and wake up */
237 	sh_msiof_write(p, SIIER, 0);
238 	complete(&p->done);
239 
240 	return IRQ_HANDLED;
241 }
242 
243 static void sh_msiof_spi_reset_regs(struct sh_msiof_spi_priv *p)
244 {
245 	u32 mask = SICTR_TXRST | SICTR_RXRST;
246 	u32 data;
247 
248 	data = sh_msiof_read(p, SICTR);
249 	data |= mask;
250 	sh_msiof_write(p, SICTR, data);
251 
252 	readl_poll_timeout_atomic(p->mapbase + SICTR, data, !(data & mask), 1,
253 				  100);
254 }
255 
256 static const u32 sh_msiof_spi_div_array[] = {
257 	SISCR_BRDV_DIV_1, SISCR_BRDV_DIV_2, SISCR_BRDV_DIV_4,
258 	SISCR_BRDV_DIV_8, SISCR_BRDV_DIV_16, SISCR_BRDV_DIV_32,
259 };
260 
261 static void sh_msiof_spi_set_clk_regs(struct sh_msiof_spi_priv *p,
262 				      unsigned long parent_rate, u32 spi_hz)
263 {
264 	unsigned long div;
265 	u32 brps, scr;
266 	unsigned int div_pow = p->min_div_pow;
267 
268 	if (!spi_hz || !parent_rate) {
269 		WARN(1, "Invalid clock rate parameters %lu and %u\n",
270 		     parent_rate, spi_hz);
271 		return;
272 	}
273 
274 	div = DIV_ROUND_UP(parent_rate, spi_hz);
275 	if (div <= 1024) {
276 		/* SISCR_BRDV_DIV_1 is valid only if BRPS is x 1/1 or x 1/2 */
277 		if (!div_pow && div <= 32 && div > 2)
278 			div_pow = 1;
279 
280 		if (div_pow)
281 			brps = (div + 1) >> div_pow;
282 		else
283 			brps = div;
284 
285 		for (; brps > 32; div_pow++)
286 			brps = (brps + 1) >> 1;
287 	} else {
288 		/* Set transfer rate composite divisor to 2^5 * 32 = 1024 */
289 		dev_err(&p->pdev->dev,
290 			"Requested SPI transfer rate %d is too low\n", spi_hz);
291 		div_pow = 5;
292 		brps = 32;
293 	}
294 
295 	scr = sh_msiof_spi_div_array[div_pow] | SISCR_BRPS(brps);
296 	sh_msiof_write(p, SITSCR, scr);
297 	if (!(p->ctlr->flags & SPI_CONTROLLER_MUST_TX))
298 		sh_msiof_write(p, SIRSCR, scr);
299 }
300 
301 static u32 sh_msiof_get_delay_bit(u32 dtdl_or_syncdl)
302 {
303 	/*
304 	 * DTDL/SYNCDL bit	: p->info->dtdl or p->info->syncdl
305 	 * b'000		: 0
306 	 * b'001		: 100
307 	 * b'010		: 200
308 	 * b'011 (SYNCDL only)	: 300
309 	 * b'101		: 50
310 	 * b'110		: 150
311 	 */
312 	if (dtdl_or_syncdl % 100)
313 		return dtdl_or_syncdl / 100 + 5;
314 	else
315 		return dtdl_or_syncdl / 100;
316 }
317 
318 static u32 sh_msiof_spi_get_dtdl_and_syncdl(struct sh_msiof_spi_priv *p)
319 {
320 	u32 val;
321 
322 	if (!p->info)
323 		return 0;
324 
325 	/* check if DTDL and SYNCDL is allowed value */
326 	if (p->info->dtdl > 200 || p->info->syncdl > 300) {
327 		dev_warn(&p->pdev->dev, "DTDL or SYNCDL is too large\n");
328 		return 0;
329 	}
330 
331 	/* check if the sum of DTDL and SYNCDL becomes an integer value  */
332 	if ((p->info->dtdl + p->info->syncdl) % 100) {
333 		dev_warn(&p->pdev->dev, "the sum of DTDL/SYNCDL is not good\n");
334 		return 0;
335 	}
336 
337 	val = sh_msiof_get_delay_bit(p->info->dtdl) << SIMDR1_DTDL_SHIFT;
338 	val |= sh_msiof_get_delay_bit(p->info->syncdl) << SIMDR1_SYNCDL_SHIFT;
339 
340 	return val;
341 }
342 
343 static void sh_msiof_spi_set_pin_regs(struct sh_msiof_spi_priv *p, u32 ss,
344 				      u32 cpol, u32 cpha,
345 				      u32 tx_hi_z, u32 lsb_first, u32 cs_high)
346 {
347 	u32 tmp;
348 	int edge;
349 
350 	/*
351 	 * CPOL CPHA     TSCKIZ RSCKIZ TEDG REDG
352 	 *    0    0         10     10    1    1
353 	 *    0    1         10     10    0    0
354 	 *    1    0         11     11    0    0
355 	 *    1    1         11     11    1    1
356 	 */
357 	tmp = SIMDR1_SYNCMD_SPI | 1 << SIMDR1_FLD_SHIFT | SIMDR1_XXSTP;
358 	tmp |= !cs_high << SIMDR1_SYNCAC_SHIFT;
359 	tmp |= lsb_first << SIMDR1_BITLSB_SHIFT;
360 	tmp |= sh_msiof_spi_get_dtdl_and_syncdl(p);
361 	if (spi_controller_is_slave(p->ctlr)) {
362 		sh_msiof_write(p, SITMDR1, tmp | SITMDR1_PCON);
363 	} else {
364 		sh_msiof_write(p, SITMDR1,
365 			       tmp | SIMDR1_TRMD | SITMDR1_PCON |
366 			       (ss < MAX_SS ? ss : 0) << SITMDR1_SYNCCH_SHIFT);
367 	}
368 	if (p->ctlr->flags & SPI_CONTROLLER_MUST_TX) {
369 		/* These bits are reserved if RX needs TX */
370 		tmp &= ~0x0000ffff;
371 	}
372 	sh_msiof_write(p, SIRMDR1, tmp);
373 
374 	tmp = 0;
375 	tmp |= SICTR_TSCKIZ_SCK | cpol << SICTR_TSCKIZ_POL_SHIFT;
376 	tmp |= SICTR_RSCKIZ_SCK | cpol << SICTR_RSCKIZ_POL_SHIFT;
377 
378 	edge = cpol ^ !cpha;
379 
380 	tmp |= edge << SICTR_TEDG_SHIFT;
381 	tmp |= edge << SICTR_REDG_SHIFT;
382 	tmp |= tx_hi_z ? SICTR_TXDIZ_HIZ : SICTR_TXDIZ_LOW;
383 	sh_msiof_write(p, SICTR, tmp);
384 }
385 
386 static void sh_msiof_spi_set_mode_regs(struct sh_msiof_spi_priv *p,
387 				       const void *tx_buf, void *rx_buf,
388 				       u32 bits, u32 words)
389 {
390 	u32 dr2 = SIMDR2_BITLEN1(bits) | SIMDR2_WDLEN1(words);
391 
392 	if (tx_buf || (p->ctlr->flags & SPI_CONTROLLER_MUST_TX))
393 		sh_msiof_write(p, SITMDR2, dr2);
394 	else
395 		sh_msiof_write(p, SITMDR2, dr2 | SIMDR2_GRPMASK1);
396 
397 	if (rx_buf)
398 		sh_msiof_write(p, SIRMDR2, dr2);
399 }
400 
401 static void sh_msiof_reset_str(struct sh_msiof_spi_priv *p)
402 {
403 	sh_msiof_write(p, SISTR,
404 		       sh_msiof_read(p, SISTR) & ~(SISTR_TDREQ | SISTR_RDREQ));
405 }
406 
407 static void sh_msiof_spi_write_fifo_8(struct sh_msiof_spi_priv *p,
408 				      const void *tx_buf, int words, int fs)
409 {
410 	const u8 *buf_8 = tx_buf;
411 	int k;
412 
413 	for (k = 0; k < words; k++)
414 		sh_msiof_write(p, SITFDR, buf_8[k] << fs);
415 }
416 
417 static void sh_msiof_spi_write_fifo_16(struct sh_msiof_spi_priv *p,
418 				       const void *tx_buf, int words, int fs)
419 {
420 	const u16 *buf_16 = tx_buf;
421 	int k;
422 
423 	for (k = 0; k < words; k++)
424 		sh_msiof_write(p, SITFDR, buf_16[k] << fs);
425 }
426 
427 static void sh_msiof_spi_write_fifo_16u(struct sh_msiof_spi_priv *p,
428 					const void *tx_buf, int words, int fs)
429 {
430 	const u16 *buf_16 = tx_buf;
431 	int k;
432 
433 	for (k = 0; k < words; k++)
434 		sh_msiof_write(p, SITFDR, get_unaligned(&buf_16[k]) << fs);
435 }
436 
437 static void sh_msiof_spi_write_fifo_32(struct sh_msiof_spi_priv *p,
438 				       const void *tx_buf, int words, int fs)
439 {
440 	const u32 *buf_32 = tx_buf;
441 	int k;
442 
443 	for (k = 0; k < words; k++)
444 		sh_msiof_write(p, SITFDR, buf_32[k] << fs);
445 }
446 
447 static void sh_msiof_spi_write_fifo_32u(struct sh_msiof_spi_priv *p,
448 					const void *tx_buf, int words, int fs)
449 {
450 	const u32 *buf_32 = tx_buf;
451 	int k;
452 
453 	for (k = 0; k < words; k++)
454 		sh_msiof_write(p, SITFDR, get_unaligned(&buf_32[k]) << fs);
455 }
456 
457 static void sh_msiof_spi_write_fifo_s32(struct sh_msiof_spi_priv *p,
458 					const void *tx_buf, int words, int fs)
459 {
460 	const u32 *buf_32 = tx_buf;
461 	int k;
462 
463 	for (k = 0; k < words; k++)
464 		sh_msiof_write(p, SITFDR, swab32(buf_32[k] << fs));
465 }
466 
467 static void sh_msiof_spi_write_fifo_s32u(struct sh_msiof_spi_priv *p,
468 					 const void *tx_buf, int words, int fs)
469 {
470 	const u32 *buf_32 = tx_buf;
471 	int k;
472 
473 	for (k = 0; k < words; k++)
474 		sh_msiof_write(p, SITFDR, swab32(get_unaligned(&buf_32[k]) << fs));
475 }
476 
477 static void sh_msiof_spi_read_fifo_8(struct sh_msiof_spi_priv *p,
478 				     void *rx_buf, int words, int fs)
479 {
480 	u8 *buf_8 = rx_buf;
481 	int k;
482 
483 	for (k = 0; k < words; k++)
484 		buf_8[k] = sh_msiof_read(p, SIRFDR) >> fs;
485 }
486 
487 static void sh_msiof_spi_read_fifo_16(struct sh_msiof_spi_priv *p,
488 				      void *rx_buf, int words, int fs)
489 {
490 	u16 *buf_16 = rx_buf;
491 	int k;
492 
493 	for (k = 0; k < words; k++)
494 		buf_16[k] = sh_msiof_read(p, SIRFDR) >> fs;
495 }
496 
497 static void sh_msiof_spi_read_fifo_16u(struct sh_msiof_spi_priv *p,
498 				       void *rx_buf, int words, int fs)
499 {
500 	u16 *buf_16 = rx_buf;
501 	int k;
502 
503 	for (k = 0; k < words; k++)
504 		put_unaligned(sh_msiof_read(p, SIRFDR) >> fs, &buf_16[k]);
505 }
506 
507 static void sh_msiof_spi_read_fifo_32(struct sh_msiof_spi_priv *p,
508 				      void *rx_buf, int words, int fs)
509 {
510 	u32 *buf_32 = rx_buf;
511 	int k;
512 
513 	for (k = 0; k < words; k++)
514 		buf_32[k] = sh_msiof_read(p, SIRFDR) >> fs;
515 }
516 
517 static void sh_msiof_spi_read_fifo_32u(struct sh_msiof_spi_priv *p,
518 				       void *rx_buf, int words, int fs)
519 {
520 	u32 *buf_32 = rx_buf;
521 	int k;
522 
523 	for (k = 0; k < words; k++)
524 		put_unaligned(sh_msiof_read(p, SIRFDR) >> fs, &buf_32[k]);
525 }
526 
527 static void sh_msiof_spi_read_fifo_s32(struct sh_msiof_spi_priv *p,
528 				       void *rx_buf, int words, int fs)
529 {
530 	u32 *buf_32 = rx_buf;
531 	int k;
532 
533 	for (k = 0; k < words; k++)
534 		buf_32[k] = swab32(sh_msiof_read(p, SIRFDR) >> fs);
535 }
536 
537 static void sh_msiof_spi_read_fifo_s32u(struct sh_msiof_spi_priv *p,
538 				       void *rx_buf, int words, int fs)
539 {
540 	u32 *buf_32 = rx_buf;
541 	int k;
542 
543 	for (k = 0; k < words; k++)
544 		put_unaligned(swab32(sh_msiof_read(p, SIRFDR) >> fs), &buf_32[k]);
545 }
546 
547 static int sh_msiof_spi_setup(struct spi_device *spi)
548 {
549 	struct sh_msiof_spi_priv *p =
550 		spi_controller_get_devdata(spi->controller);
551 	u32 clr, set, tmp;
552 
553 	if (spi->cs_gpiod || spi_controller_is_slave(p->ctlr))
554 		return 0;
555 
556 	if (p->native_cs_inited &&
557 	    (p->native_cs_high == !!(spi->mode & SPI_CS_HIGH)))
558 		return 0;
559 
560 	/* Configure native chip select mode/polarity early */
561 	clr = SIMDR1_SYNCMD_MASK;
562 	set = SIMDR1_SYNCMD_SPI;
563 	if (spi->mode & SPI_CS_HIGH)
564 		clr |= BIT(SIMDR1_SYNCAC_SHIFT);
565 	else
566 		set |= BIT(SIMDR1_SYNCAC_SHIFT);
567 	pm_runtime_get_sync(&p->pdev->dev);
568 	tmp = sh_msiof_read(p, SITMDR1) & ~clr;
569 	sh_msiof_write(p, SITMDR1, tmp | set | SIMDR1_TRMD | SITMDR1_PCON);
570 	tmp = sh_msiof_read(p, SIRMDR1) & ~clr;
571 	sh_msiof_write(p, SIRMDR1, tmp | set);
572 	pm_runtime_put(&p->pdev->dev);
573 	p->native_cs_high = spi->mode & SPI_CS_HIGH;
574 	p->native_cs_inited = true;
575 	return 0;
576 }
577 
578 static int sh_msiof_prepare_message(struct spi_controller *ctlr,
579 				    struct spi_message *msg)
580 {
581 	struct sh_msiof_spi_priv *p = spi_controller_get_devdata(ctlr);
582 	const struct spi_device *spi = msg->spi;
583 	u32 ss, cs_high;
584 
585 	/* Configure pins before asserting CS */
586 	if (spi->cs_gpiod) {
587 		ss = ctlr->unused_native_cs;
588 		cs_high = p->native_cs_high;
589 	} else {
590 		ss = spi->chip_select;
591 		cs_high = !!(spi->mode & SPI_CS_HIGH);
592 	}
593 	sh_msiof_spi_set_pin_regs(p, ss, !!(spi->mode & SPI_CPOL),
594 				  !!(spi->mode & SPI_CPHA),
595 				  !!(spi->mode & SPI_3WIRE),
596 				  !!(spi->mode & SPI_LSB_FIRST), cs_high);
597 	return 0;
598 }
599 
600 static int sh_msiof_spi_start(struct sh_msiof_spi_priv *p, void *rx_buf)
601 {
602 	bool slave = spi_controller_is_slave(p->ctlr);
603 	int ret = 0;
604 
605 	/* setup clock and rx/tx signals */
606 	if (!slave)
607 		ret = sh_msiof_modify_ctr_wait(p, 0, SICTR_TSCKE);
608 	if (rx_buf && !ret)
609 		ret = sh_msiof_modify_ctr_wait(p, 0, SICTR_RXE);
610 	if (!ret)
611 		ret = sh_msiof_modify_ctr_wait(p, 0, SICTR_TXE);
612 
613 	/* start by setting frame bit */
614 	if (!ret && !slave)
615 		ret = sh_msiof_modify_ctr_wait(p, 0, SICTR_TFSE);
616 
617 	return ret;
618 }
619 
620 static int sh_msiof_spi_stop(struct sh_msiof_spi_priv *p, void *rx_buf)
621 {
622 	bool slave = spi_controller_is_slave(p->ctlr);
623 	int ret = 0;
624 
625 	/* shut down frame, rx/tx and clock signals */
626 	if (!slave)
627 		ret = sh_msiof_modify_ctr_wait(p, SICTR_TFSE, 0);
628 	if (!ret)
629 		ret = sh_msiof_modify_ctr_wait(p, SICTR_TXE, 0);
630 	if (rx_buf && !ret)
631 		ret = sh_msiof_modify_ctr_wait(p, SICTR_RXE, 0);
632 	if (!ret && !slave)
633 		ret = sh_msiof_modify_ctr_wait(p, SICTR_TSCKE, 0);
634 
635 	return ret;
636 }
637 
638 static int sh_msiof_slave_abort(struct spi_controller *ctlr)
639 {
640 	struct sh_msiof_spi_priv *p = spi_controller_get_devdata(ctlr);
641 
642 	p->slave_aborted = true;
643 	complete(&p->done);
644 	complete(&p->done_txdma);
645 	return 0;
646 }
647 
648 static int sh_msiof_wait_for_completion(struct sh_msiof_spi_priv *p,
649 					struct completion *x)
650 {
651 	if (spi_controller_is_slave(p->ctlr)) {
652 		if (wait_for_completion_interruptible(x) ||
653 		    p->slave_aborted) {
654 			dev_dbg(&p->pdev->dev, "interrupted\n");
655 			return -EINTR;
656 		}
657 	} else {
658 		if (!wait_for_completion_timeout(x, HZ)) {
659 			dev_err(&p->pdev->dev, "timeout\n");
660 			return -ETIMEDOUT;
661 		}
662 	}
663 
664 	return 0;
665 }
666 
667 static int sh_msiof_spi_txrx_once(struct sh_msiof_spi_priv *p,
668 				  void (*tx_fifo)(struct sh_msiof_spi_priv *,
669 						  const void *, int, int),
670 				  void (*rx_fifo)(struct sh_msiof_spi_priv *,
671 						  void *, int, int),
672 				  const void *tx_buf, void *rx_buf,
673 				  int words, int bits)
674 {
675 	int fifo_shift;
676 	int ret;
677 
678 	/* limit maximum word transfer to rx/tx fifo size */
679 	if (tx_buf)
680 		words = min_t(int, words, p->tx_fifo_size);
681 	if (rx_buf)
682 		words = min_t(int, words, p->rx_fifo_size);
683 
684 	/* the fifo contents need shifting */
685 	fifo_shift = 32 - bits;
686 
687 	/* default FIFO watermarks for PIO */
688 	sh_msiof_write(p, SIFCTR, 0);
689 
690 	/* setup msiof transfer mode registers */
691 	sh_msiof_spi_set_mode_regs(p, tx_buf, rx_buf, bits, words);
692 	sh_msiof_write(p, SIIER, SIIER_TEOFE | SIIER_REOFE);
693 
694 	/* write tx fifo */
695 	if (tx_buf)
696 		tx_fifo(p, tx_buf, words, fifo_shift);
697 
698 	reinit_completion(&p->done);
699 	p->slave_aborted = false;
700 
701 	ret = sh_msiof_spi_start(p, rx_buf);
702 	if (ret) {
703 		dev_err(&p->pdev->dev, "failed to start hardware\n");
704 		goto stop_ier;
705 	}
706 
707 	/* wait for tx fifo to be emptied / rx fifo to be filled */
708 	ret = sh_msiof_wait_for_completion(p, &p->done);
709 	if (ret)
710 		goto stop_reset;
711 
712 	/* read rx fifo */
713 	if (rx_buf)
714 		rx_fifo(p, rx_buf, words, fifo_shift);
715 
716 	/* clear status bits */
717 	sh_msiof_reset_str(p);
718 
719 	ret = sh_msiof_spi_stop(p, rx_buf);
720 	if (ret) {
721 		dev_err(&p->pdev->dev, "failed to shut down hardware\n");
722 		return ret;
723 	}
724 
725 	return words;
726 
727 stop_reset:
728 	sh_msiof_reset_str(p);
729 	sh_msiof_spi_stop(p, rx_buf);
730 stop_ier:
731 	sh_msiof_write(p, SIIER, 0);
732 	return ret;
733 }
734 
735 static void sh_msiof_dma_complete(void *arg)
736 {
737 	complete(arg);
738 }
739 
740 static int sh_msiof_dma_once(struct sh_msiof_spi_priv *p, const void *tx,
741 			     void *rx, unsigned int len)
742 {
743 	u32 ier_bits = 0;
744 	struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL;
745 	dma_cookie_t cookie;
746 	int ret;
747 
748 	/* First prepare and submit the DMA request(s), as this may fail */
749 	if (rx) {
750 		ier_bits |= SIIER_RDREQE | SIIER_RDMAE;
751 		desc_rx = dmaengine_prep_slave_single(p->ctlr->dma_rx,
752 					p->rx_dma_addr, len, DMA_DEV_TO_MEM,
753 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
754 		if (!desc_rx)
755 			return -EAGAIN;
756 
757 		desc_rx->callback = sh_msiof_dma_complete;
758 		desc_rx->callback_param = &p->done;
759 		cookie = dmaengine_submit(desc_rx);
760 		if (dma_submit_error(cookie))
761 			return cookie;
762 	}
763 
764 	if (tx) {
765 		ier_bits |= SIIER_TDREQE | SIIER_TDMAE;
766 		dma_sync_single_for_device(p->ctlr->dma_tx->device->dev,
767 					   p->tx_dma_addr, len, DMA_TO_DEVICE);
768 		desc_tx = dmaengine_prep_slave_single(p->ctlr->dma_tx,
769 					p->tx_dma_addr, len, DMA_MEM_TO_DEV,
770 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
771 		if (!desc_tx) {
772 			ret = -EAGAIN;
773 			goto no_dma_tx;
774 		}
775 
776 		desc_tx->callback = sh_msiof_dma_complete;
777 		desc_tx->callback_param = &p->done_txdma;
778 		cookie = dmaengine_submit(desc_tx);
779 		if (dma_submit_error(cookie)) {
780 			ret = cookie;
781 			goto no_dma_tx;
782 		}
783 	}
784 
785 	/* 1 stage FIFO watermarks for DMA */
786 	sh_msiof_write(p, SIFCTR, SIFCTR_TFWM_1 | SIFCTR_RFWM_1);
787 
788 	/* setup msiof transfer mode registers (32-bit words) */
789 	sh_msiof_spi_set_mode_regs(p, tx, rx, 32, len / 4);
790 
791 	sh_msiof_write(p, SIIER, ier_bits);
792 
793 	reinit_completion(&p->done);
794 	if (tx)
795 		reinit_completion(&p->done_txdma);
796 	p->slave_aborted = false;
797 
798 	/* Now start DMA */
799 	if (rx)
800 		dma_async_issue_pending(p->ctlr->dma_rx);
801 	if (tx)
802 		dma_async_issue_pending(p->ctlr->dma_tx);
803 
804 	ret = sh_msiof_spi_start(p, rx);
805 	if (ret) {
806 		dev_err(&p->pdev->dev, "failed to start hardware\n");
807 		goto stop_dma;
808 	}
809 
810 	if (tx) {
811 		/* wait for tx DMA completion */
812 		ret = sh_msiof_wait_for_completion(p, &p->done_txdma);
813 		if (ret)
814 			goto stop_reset;
815 	}
816 
817 	if (rx) {
818 		/* wait for rx DMA completion */
819 		ret = sh_msiof_wait_for_completion(p, &p->done);
820 		if (ret)
821 			goto stop_reset;
822 
823 		sh_msiof_write(p, SIIER, 0);
824 	} else {
825 		/* wait for tx fifo to be emptied */
826 		sh_msiof_write(p, SIIER, SIIER_TEOFE);
827 		ret = sh_msiof_wait_for_completion(p, &p->done);
828 		if (ret)
829 			goto stop_reset;
830 	}
831 
832 	/* clear status bits */
833 	sh_msiof_reset_str(p);
834 
835 	ret = sh_msiof_spi_stop(p, rx);
836 	if (ret) {
837 		dev_err(&p->pdev->dev, "failed to shut down hardware\n");
838 		return ret;
839 	}
840 
841 	if (rx)
842 		dma_sync_single_for_cpu(p->ctlr->dma_rx->device->dev,
843 					p->rx_dma_addr, len, DMA_FROM_DEVICE);
844 
845 	return 0;
846 
847 stop_reset:
848 	sh_msiof_reset_str(p);
849 	sh_msiof_spi_stop(p, rx);
850 stop_dma:
851 	if (tx)
852 		dmaengine_terminate_all(p->ctlr->dma_tx);
853 no_dma_tx:
854 	if (rx)
855 		dmaengine_terminate_all(p->ctlr->dma_rx);
856 	sh_msiof_write(p, SIIER, 0);
857 	return ret;
858 }
859 
860 static void copy_bswap32(u32 *dst, const u32 *src, unsigned int words)
861 {
862 	/* src or dst can be unaligned, but not both */
863 	if ((unsigned long)src & 3) {
864 		while (words--) {
865 			*dst++ = swab32(get_unaligned(src));
866 			src++;
867 		}
868 	} else if ((unsigned long)dst & 3) {
869 		while (words--) {
870 			put_unaligned(swab32(*src++), dst);
871 			dst++;
872 		}
873 	} else {
874 		while (words--)
875 			*dst++ = swab32(*src++);
876 	}
877 }
878 
879 static void copy_wswap32(u32 *dst, const u32 *src, unsigned int words)
880 {
881 	/* src or dst can be unaligned, but not both */
882 	if ((unsigned long)src & 3) {
883 		while (words--) {
884 			*dst++ = swahw32(get_unaligned(src));
885 			src++;
886 		}
887 	} else if ((unsigned long)dst & 3) {
888 		while (words--) {
889 			put_unaligned(swahw32(*src++), dst);
890 			dst++;
891 		}
892 	} else {
893 		while (words--)
894 			*dst++ = swahw32(*src++);
895 	}
896 }
897 
898 static void copy_plain32(u32 *dst, const u32 *src, unsigned int words)
899 {
900 	memcpy(dst, src, words * 4);
901 }
902 
903 static int sh_msiof_transfer_one(struct spi_controller *ctlr,
904 				 struct spi_device *spi,
905 				 struct spi_transfer *t)
906 {
907 	struct sh_msiof_spi_priv *p = spi_controller_get_devdata(ctlr);
908 	void (*copy32)(u32 *, const u32 *, unsigned int);
909 	void (*tx_fifo)(struct sh_msiof_spi_priv *, const void *, int, int);
910 	void (*rx_fifo)(struct sh_msiof_spi_priv *, void *, int, int);
911 	const void *tx_buf = t->tx_buf;
912 	void *rx_buf = t->rx_buf;
913 	unsigned int len = t->len;
914 	unsigned int bits = t->bits_per_word;
915 	unsigned int bytes_per_word;
916 	unsigned int words;
917 	int n;
918 	bool swab;
919 	int ret;
920 
921 	/* reset registers */
922 	sh_msiof_spi_reset_regs(p);
923 
924 	/* setup clocks (clock already enabled in chipselect()) */
925 	if (!spi_controller_is_slave(p->ctlr))
926 		sh_msiof_spi_set_clk_regs(p, clk_get_rate(p->clk), t->speed_hz);
927 
928 	while (ctlr->dma_tx && len > 15) {
929 		/*
930 		 *  DMA supports 32-bit words only, hence pack 8-bit and 16-bit
931 		 *  words, with byte resp. word swapping.
932 		 */
933 		unsigned int l = 0;
934 
935 		if (tx_buf)
936 			l = min(round_down(len, 4), p->tx_fifo_size * 4);
937 		if (rx_buf)
938 			l = min(round_down(len, 4), p->rx_fifo_size * 4);
939 
940 		if (bits <= 8) {
941 			copy32 = copy_bswap32;
942 		} else if (bits <= 16) {
943 			copy32 = copy_wswap32;
944 		} else {
945 			copy32 = copy_plain32;
946 		}
947 
948 		if (tx_buf)
949 			copy32(p->tx_dma_page, tx_buf, l / 4);
950 
951 		ret = sh_msiof_dma_once(p, tx_buf, rx_buf, l);
952 		if (ret == -EAGAIN) {
953 			dev_warn_once(&p->pdev->dev,
954 				"DMA not available, falling back to PIO\n");
955 			break;
956 		}
957 		if (ret)
958 			return ret;
959 
960 		if (rx_buf) {
961 			copy32(rx_buf, p->rx_dma_page, l / 4);
962 			rx_buf += l;
963 		}
964 		if (tx_buf)
965 			tx_buf += l;
966 
967 		len -= l;
968 		if (!len)
969 			return 0;
970 	}
971 
972 	if (bits <= 8 && len > 15) {
973 		bits = 32;
974 		swab = true;
975 	} else {
976 		swab = false;
977 	}
978 
979 	/* setup bytes per word and fifo read/write functions */
980 	if (bits <= 8) {
981 		bytes_per_word = 1;
982 		tx_fifo = sh_msiof_spi_write_fifo_8;
983 		rx_fifo = sh_msiof_spi_read_fifo_8;
984 	} else if (bits <= 16) {
985 		bytes_per_word = 2;
986 		if ((unsigned long)tx_buf & 0x01)
987 			tx_fifo = sh_msiof_spi_write_fifo_16u;
988 		else
989 			tx_fifo = sh_msiof_spi_write_fifo_16;
990 
991 		if ((unsigned long)rx_buf & 0x01)
992 			rx_fifo = sh_msiof_spi_read_fifo_16u;
993 		else
994 			rx_fifo = sh_msiof_spi_read_fifo_16;
995 	} else if (swab) {
996 		bytes_per_word = 4;
997 		if ((unsigned long)tx_buf & 0x03)
998 			tx_fifo = sh_msiof_spi_write_fifo_s32u;
999 		else
1000 			tx_fifo = sh_msiof_spi_write_fifo_s32;
1001 
1002 		if ((unsigned long)rx_buf & 0x03)
1003 			rx_fifo = sh_msiof_spi_read_fifo_s32u;
1004 		else
1005 			rx_fifo = sh_msiof_spi_read_fifo_s32;
1006 	} else {
1007 		bytes_per_word = 4;
1008 		if ((unsigned long)tx_buf & 0x03)
1009 			tx_fifo = sh_msiof_spi_write_fifo_32u;
1010 		else
1011 			tx_fifo = sh_msiof_spi_write_fifo_32;
1012 
1013 		if ((unsigned long)rx_buf & 0x03)
1014 			rx_fifo = sh_msiof_spi_read_fifo_32u;
1015 		else
1016 			rx_fifo = sh_msiof_spi_read_fifo_32;
1017 	}
1018 
1019 	/* transfer in fifo sized chunks */
1020 	words = len / bytes_per_word;
1021 
1022 	while (words > 0) {
1023 		n = sh_msiof_spi_txrx_once(p, tx_fifo, rx_fifo, tx_buf, rx_buf,
1024 					   words, bits);
1025 		if (n < 0)
1026 			return n;
1027 
1028 		if (tx_buf)
1029 			tx_buf += n * bytes_per_word;
1030 		if (rx_buf)
1031 			rx_buf += n * bytes_per_word;
1032 		words -= n;
1033 
1034 		if (words == 0 && (len % bytes_per_word)) {
1035 			words = len % bytes_per_word;
1036 			bits = t->bits_per_word;
1037 			bytes_per_word = 1;
1038 			tx_fifo = sh_msiof_spi_write_fifo_8;
1039 			rx_fifo = sh_msiof_spi_read_fifo_8;
1040 		}
1041 	}
1042 
1043 	return 0;
1044 }
1045 
1046 static const struct sh_msiof_chipdata sh_data = {
1047 	.bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 32),
1048 	.tx_fifo_size = 64,
1049 	.rx_fifo_size = 64,
1050 	.ctlr_flags = 0,
1051 	.min_div_pow = 0,
1052 };
1053 
1054 static const struct sh_msiof_chipdata rcar_gen2_data = {
1055 	.bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16) |
1056 			      SPI_BPW_MASK(24) | SPI_BPW_MASK(32),
1057 	.tx_fifo_size = 64,
1058 	.rx_fifo_size = 64,
1059 	.ctlr_flags = SPI_CONTROLLER_MUST_TX,
1060 	.min_div_pow = 0,
1061 };
1062 
1063 static const struct sh_msiof_chipdata rcar_gen3_data = {
1064 	.bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16) |
1065 			      SPI_BPW_MASK(24) | SPI_BPW_MASK(32),
1066 	.tx_fifo_size = 64,
1067 	.rx_fifo_size = 64,
1068 	.ctlr_flags = SPI_CONTROLLER_MUST_TX,
1069 	.min_div_pow = 1,
1070 };
1071 
1072 static const struct of_device_id sh_msiof_match[] = {
1073 	{ .compatible = "renesas,sh-mobile-msiof", .data = &sh_data },
1074 	{ .compatible = "renesas,msiof-r8a7743",   .data = &rcar_gen2_data },
1075 	{ .compatible = "renesas,msiof-r8a7745",   .data = &rcar_gen2_data },
1076 	{ .compatible = "renesas,msiof-r8a7790",   .data = &rcar_gen2_data },
1077 	{ .compatible = "renesas,msiof-r8a7791",   .data = &rcar_gen2_data },
1078 	{ .compatible = "renesas,msiof-r8a7792",   .data = &rcar_gen2_data },
1079 	{ .compatible = "renesas,msiof-r8a7793",   .data = &rcar_gen2_data },
1080 	{ .compatible = "renesas,msiof-r8a7794",   .data = &rcar_gen2_data },
1081 	{ .compatible = "renesas,rcar-gen2-msiof", .data = &rcar_gen2_data },
1082 	{ .compatible = "renesas,msiof-r8a7796",   .data = &rcar_gen3_data },
1083 	{ .compatible = "renesas,rcar-gen3-msiof", .data = &rcar_gen3_data },
1084 	{ .compatible = "renesas,sh-msiof",        .data = &sh_data }, /* Deprecated */
1085 	{},
1086 };
1087 MODULE_DEVICE_TABLE(of, sh_msiof_match);
1088 
1089 #ifdef CONFIG_OF
1090 static struct sh_msiof_spi_info *sh_msiof_spi_parse_dt(struct device *dev)
1091 {
1092 	struct sh_msiof_spi_info *info;
1093 	struct device_node *np = dev->of_node;
1094 	u32 num_cs = 1;
1095 
1096 	info = devm_kzalloc(dev, sizeof(struct sh_msiof_spi_info), GFP_KERNEL);
1097 	if (!info)
1098 		return NULL;
1099 
1100 	info->mode = of_property_read_bool(np, "spi-slave") ? MSIOF_SPI_SLAVE
1101 							    : MSIOF_SPI_MASTER;
1102 
1103 	/* Parse the MSIOF properties */
1104 	if (info->mode == MSIOF_SPI_MASTER)
1105 		of_property_read_u32(np, "num-cs", &num_cs);
1106 	of_property_read_u32(np, "renesas,tx-fifo-size",
1107 					&info->tx_fifo_override);
1108 	of_property_read_u32(np, "renesas,rx-fifo-size",
1109 					&info->rx_fifo_override);
1110 	of_property_read_u32(np, "renesas,dtdl", &info->dtdl);
1111 	of_property_read_u32(np, "renesas,syncdl", &info->syncdl);
1112 
1113 	info->num_chipselect = num_cs;
1114 
1115 	return info;
1116 }
1117 #else
1118 static struct sh_msiof_spi_info *sh_msiof_spi_parse_dt(struct device *dev)
1119 {
1120 	return NULL;
1121 }
1122 #endif
1123 
1124 static struct dma_chan *sh_msiof_request_dma_chan(struct device *dev,
1125 	enum dma_transfer_direction dir, unsigned int id, dma_addr_t port_addr)
1126 {
1127 	dma_cap_mask_t mask;
1128 	struct dma_chan *chan;
1129 	struct dma_slave_config cfg;
1130 	int ret;
1131 
1132 	dma_cap_zero(mask);
1133 	dma_cap_set(DMA_SLAVE, mask);
1134 
1135 	chan = dma_request_slave_channel_compat(mask, shdma_chan_filter,
1136 				(void *)(unsigned long)id, dev,
1137 				dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1138 	if (!chan) {
1139 		dev_warn(dev, "dma_request_slave_channel_compat failed\n");
1140 		return NULL;
1141 	}
1142 
1143 	memset(&cfg, 0, sizeof(cfg));
1144 	cfg.direction = dir;
1145 	if (dir == DMA_MEM_TO_DEV) {
1146 		cfg.dst_addr = port_addr;
1147 		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1148 	} else {
1149 		cfg.src_addr = port_addr;
1150 		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1151 	}
1152 
1153 	ret = dmaengine_slave_config(chan, &cfg);
1154 	if (ret) {
1155 		dev_warn(dev, "dmaengine_slave_config failed %d\n", ret);
1156 		dma_release_channel(chan);
1157 		return NULL;
1158 	}
1159 
1160 	return chan;
1161 }
1162 
1163 static int sh_msiof_request_dma(struct sh_msiof_spi_priv *p)
1164 {
1165 	struct platform_device *pdev = p->pdev;
1166 	struct device *dev = &pdev->dev;
1167 	const struct sh_msiof_spi_info *info = p->info;
1168 	unsigned int dma_tx_id, dma_rx_id;
1169 	const struct resource *res;
1170 	struct spi_controller *ctlr;
1171 	struct device *tx_dev, *rx_dev;
1172 
1173 	if (dev->of_node) {
1174 		/* In the OF case we will get the slave IDs from the DT */
1175 		dma_tx_id = 0;
1176 		dma_rx_id = 0;
1177 	} else if (info && info->dma_tx_id && info->dma_rx_id) {
1178 		dma_tx_id = info->dma_tx_id;
1179 		dma_rx_id = info->dma_rx_id;
1180 	} else {
1181 		/* The driver assumes no error */
1182 		return 0;
1183 	}
1184 
1185 	/* The DMA engine uses the second register set, if present */
1186 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1187 	if (!res)
1188 		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1189 
1190 	ctlr = p->ctlr;
1191 	ctlr->dma_tx = sh_msiof_request_dma_chan(dev, DMA_MEM_TO_DEV,
1192 						 dma_tx_id, res->start + SITFDR);
1193 	if (!ctlr->dma_tx)
1194 		return -ENODEV;
1195 
1196 	ctlr->dma_rx = sh_msiof_request_dma_chan(dev, DMA_DEV_TO_MEM,
1197 						 dma_rx_id, res->start + SIRFDR);
1198 	if (!ctlr->dma_rx)
1199 		goto free_tx_chan;
1200 
1201 	p->tx_dma_page = (void *)__get_free_page(GFP_KERNEL | GFP_DMA);
1202 	if (!p->tx_dma_page)
1203 		goto free_rx_chan;
1204 
1205 	p->rx_dma_page = (void *)__get_free_page(GFP_KERNEL | GFP_DMA);
1206 	if (!p->rx_dma_page)
1207 		goto free_tx_page;
1208 
1209 	tx_dev = ctlr->dma_tx->device->dev;
1210 	p->tx_dma_addr = dma_map_single(tx_dev, p->tx_dma_page, PAGE_SIZE,
1211 					DMA_TO_DEVICE);
1212 	if (dma_mapping_error(tx_dev, p->tx_dma_addr))
1213 		goto free_rx_page;
1214 
1215 	rx_dev = ctlr->dma_rx->device->dev;
1216 	p->rx_dma_addr = dma_map_single(rx_dev, p->rx_dma_page, PAGE_SIZE,
1217 					DMA_FROM_DEVICE);
1218 	if (dma_mapping_error(rx_dev, p->rx_dma_addr))
1219 		goto unmap_tx_page;
1220 
1221 	dev_info(dev, "DMA available");
1222 	return 0;
1223 
1224 unmap_tx_page:
1225 	dma_unmap_single(tx_dev, p->tx_dma_addr, PAGE_SIZE, DMA_TO_DEVICE);
1226 free_rx_page:
1227 	free_page((unsigned long)p->rx_dma_page);
1228 free_tx_page:
1229 	free_page((unsigned long)p->tx_dma_page);
1230 free_rx_chan:
1231 	dma_release_channel(ctlr->dma_rx);
1232 free_tx_chan:
1233 	dma_release_channel(ctlr->dma_tx);
1234 	ctlr->dma_tx = NULL;
1235 	return -ENODEV;
1236 }
1237 
1238 static void sh_msiof_release_dma(struct sh_msiof_spi_priv *p)
1239 {
1240 	struct spi_controller *ctlr = p->ctlr;
1241 
1242 	if (!ctlr->dma_tx)
1243 		return;
1244 
1245 	dma_unmap_single(ctlr->dma_rx->device->dev, p->rx_dma_addr, PAGE_SIZE,
1246 			 DMA_FROM_DEVICE);
1247 	dma_unmap_single(ctlr->dma_tx->device->dev, p->tx_dma_addr, PAGE_SIZE,
1248 			 DMA_TO_DEVICE);
1249 	free_page((unsigned long)p->rx_dma_page);
1250 	free_page((unsigned long)p->tx_dma_page);
1251 	dma_release_channel(ctlr->dma_rx);
1252 	dma_release_channel(ctlr->dma_tx);
1253 }
1254 
1255 static int sh_msiof_spi_probe(struct platform_device *pdev)
1256 {
1257 	struct spi_controller *ctlr;
1258 	const struct sh_msiof_chipdata *chipdata;
1259 	struct sh_msiof_spi_info *info;
1260 	struct sh_msiof_spi_priv *p;
1261 	int i;
1262 	int ret;
1263 
1264 	chipdata = of_device_get_match_data(&pdev->dev);
1265 	if (chipdata) {
1266 		info = sh_msiof_spi_parse_dt(&pdev->dev);
1267 	} else {
1268 		chipdata = (const void *)pdev->id_entry->driver_data;
1269 		info = dev_get_platdata(&pdev->dev);
1270 	}
1271 
1272 	if (!info) {
1273 		dev_err(&pdev->dev, "failed to obtain device info\n");
1274 		return -ENXIO;
1275 	}
1276 
1277 	if (info->mode == MSIOF_SPI_SLAVE)
1278 		ctlr = spi_alloc_slave(&pdev->dev,
1279 				       sizeof(struct sh_msiof_spi_priv));
1280 	else
1281 		ctlr = spi_alloc_master(&pdev->dev,
1282 					sizeof(struct sh_msiof_spi_priv));
1283 	if (ctlr == NULL)
1284 		return -ENOMEM;
1285 
1286 	p = spi_controller_get_devdata(ctlr);
1287 
1288 	platform_set_drvdata(pdev, p);
1289 	p->ctlr = ctlr;
1290 	p->info = info;
1291 	p->min_div_pow = chipdata->min_div_pow;
1292 
1293 	init_completion(&p->done);
1294 	init_completion(&p->done_txdma);
1295 
1296 	p->clk = devm_clk_get(&pdev->dev, NULL);
1297 	if (IS_ERR(p->clk)) {
1298 		dev_err(&pdev->dev, "cannot get clock\n");
1299 		ret = PTR_ERR(p->clk);
1300 		goto err1;
1301 	}
1302 
1303 	i = platform_get_irq(pdev, 0);
1304 	if (i < 0) {
1305 		ret = i;
1306 		goto err1;
1307 	}
1308 
1309 	p->mapbase = devm_platform_ioremap_resource(pdev, 0);
1310 	if (IS_ERR(p->mapbase)) {
1311 		ret = PTR_ERR(p->mapbase);
1312 		goto err1;
1313 	}
1314 
1315 	ret = devm_request_irq(&pdev->dev, i, sh_msiof_spi_irq, 0,
1316 			       dev_name(&pdev->dev), p);
1317 	if (ret) {
1318 		dev_err(&pdev->dev, "unable to request irq\n");
1319 		goto err1;
1320 	}
1321 
1322 	p->pdev = pdev;
1323 	pm_runtime_enable(&pdev->dev);
1324 
1325 	/* Platform data may override FIFO sizes */
1326 	p->tx_fifo_size = chipdata->tx_fifo_size;
1327 	p->rx_fifo_size = chipdata->rx_fifo_size;
1328 	if (p->info->tx_fifo_override)
1329 		p->tx_fifo_size = p->info->tx_fifo_override;
1330 	if (p->info->rx_fifo_override)
1331 		p->rx_fifo_size = p->info->rx_fifo_override;
1332 
1333 	/* init controller code */
1334 	ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1335 	ctlr->mode_bits |= SPI_LSB_FIRST | SPI_3WIRE;
1336 	ctlr->flags = chipdata->ctlr_flags;
1337 	ctlr->bus_num = pdev->id;
1338 	ctlr->num_chipselect = p->info->num_chipselect;
1339 	ctlr->dev.of_node = pdev->dev.of_node;
1340 	ctlr->setup = sh_msiof_spi_setup;
1341 	ctlr->prepare_message = sh_msiof_prepare_message;
1342 	ctlr->slave_abort = sh_msiof_slave_abort;
1343 	ctlr->bits_per_word_mask = chipdata->bits_per_word_mask;
1344 	ctlr->auto_runtime_pm = true;
1345 	ctlr->transfer_one = sh_msiof_transfer_one;
1346 	ctlr->use_gpio_descriptors = true;
1347 	ctlr->max_native_cs = MAX_SS;
1348 
1349 	ret = sh_msiof_request_dma(p);
1350 	if (ret < 0)
1351 		dev_warn(&pdev->dev, "DMA not available, using PIO\n");
1352 
1353 	ret = devm_spi_register_controller(&pdev->dev, ctlr);
1354 	if (ret < 0) {
1355 		dev_err(&pdev->dev, "devm_spi_register_controller error.\n");
1356 		goto err2;
1357 	}
1358 
1359 	return 0;
1360 
1361  err2:
1362 	sh_msiof_release_dma(p);
1363 	pm_runtime_disable(&pdev->dev);
1364  err1:
1365 	spi_controller_put(ctlr);
1366 	return ret;
1367 }
1368 
1369 static int sh_msiof_spi_remove(struct platform_device *pdev)
1370 {
1371 	struct sh_msiof_spi_priv *p = platform_get_drvdata(pdev);
1372 
1373 	sh_msiof_release_dma(p);
1374 	pm_runtime_disable(&pdev->dev);
1375 	return 0;
1376 }
1377 
1378 static const struct platform_device_id spi_driver_ids[] = {
1379 	{ "spi_sh_msiof",	(kernel_ulong_t)&sh_data },
1380 	{},
1381 };
1382 MODULE_DEVICE_TABLE(platform, spi_driver_ids);
1383 
1384 #ifdef CONFIG_PM_SLEEP
1385 static int sh_msiof_spi_suspend(struct device *dev)
1386 {
1387 	struct sh_msiof_spi_priv *p = dev_get_drvdata(dev);
1388 
1389 	return spi_controller_suspend(p->ctlr);
1390 }
1391 
1392 static int sh_msiof_spi_resume(struct device *dev)
1393 {
1394 	struct sh_msiof_spi_priv *p = dev_get_drvdata(dev);
1395 
1396 	return spi_controller_resume(p->ctlr);
1397 }
1398 
1399 static SIMPLE_DEV_PM_OPS(sh_msiof_spi_pm_ops, sh_msiof_spi_suspend,
1400 			 sh_msiof_spi_resume);
1401 #define DEV_PM_OPS	(&sh_msiof_spi_pm_ops)
1402 #else
1403 #define DEV_PM_OPS	NULL
1404 #endif /* CONFIG_PM_SLEEP */
1405 
1406 static struct platform_driver sh_msiof_spi_drv = {
1407 	.probe		= sh_msiof_spi_probe,
1408 	.remove		= sh_msiof_spi_remove,
1409 	.id_table	= spi_driver_ids,
1410 	.driver		= {
1411 		.name		= "spi_sh_msiof",
1412 		.pm		= DEV_PM_OPS,
1413 		.of_match_table = of_match_ptr(sh_msiof_match),
1414 	},
1415 };
1416 module_platform_driver(sh_msiof_spi_drv);
1417 
1418 MODULE_DESCRIPTION("SuperH MSIOF SPI Controller Interface Driver");
1419 MODULE_AUTHOR("Magnus Damm");
1420 MODULE_LICENSE("GPL v2");
1421 MODULE_ALIAS("platform:spi_sh_msiof");
1422