xref: /openbmc/linux/drivers/spi/spi-rspi.c (revision 0c874100)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * SH RSPI driver
4  *
5  * Copyright (C) 2012, 2013  Renesas Solutions Corp.
6  * Copyright (C) 2014 Glider bvba
7  *
8  * Based on spi-sh.c:
9  * Copyright (C) 2011 Renesas Solutions Corp.
10  */
11 
12 #include <linux/module.h>
13 #include <linux/kernel.h>
14 #include <linux/sched.h>
15 #include <linux/errno.h>
16 #include <linux/interrupt.h>
17 #include <linux/platform_device.h>
18 #include <linux/io.h>
19 #include <linux/clk.h>
20 #include <linux/dmaengine.h>
21 #include <linux/dma-mapping.h>
22 #include <linux/of_device.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/sh_dma.h>
25 #include <linux/spi/spi.h>
26 #include <linux/spi/rspi.h>
27 
28 #define RSPI_SPCR		0x00	/* Control Register */
29 #define RSPI_SSLP		0x01	/* Slave Select Polarity Register */
30 #define RSPI_SPPCR		0x02	/* Pin Control Register */
31 #define RSPI_SPSR		0x03	/* Status Register */
32 #define RSPI_SPDR		0x04	/* Data Register */
33 #define RSPI_SPSCR		0x08	/* Sequence Control Register */
34 #define RSPI_SPSSR		0x09	/* Sequence Status Register */
35 #define RSPI_SPBR		0x0a	/* Bit Rate Register */
36 #define RSPI_SPDCR		0x0b	/* Data Control Register */
37 #define RSPI_SPCKD		0x0c	/* Clock Delay Register */
38 #define RSPI_SSLND		0x0d	/* Slave Select Negation Delay Register */
39 #define RSPI_SPND		0x0e	/* Next-Access Delay Register */
40 #define RSPI_SPCR2		0x0f	/* Control Register 2 (SH only) */
41 #define RSPI_SPCMD0		0x10	/* Command Register 0 */
42 #define RSPI_SPCMD1		0x12	/* Command Register 1 */
43 #define RSPI_SPCMD2		0x14	/* Command Register 2 */
44 #define RSPI_SPCMD3		0x16	/* Command Register 3 */
45 #define RSPI_SPCMD4		0x18	/* Command Register 4 */
46 #define RSPI_SPCMD5		0x1a	/* Command Register 5 */
47 #define RSPI_SPCMD6		0x1c	/* Command Register 6 */
48 #define RSPI_SPCMD7		0x1e	/* Command Register 7 */
49 #define RSPI_SPCMD(i)		(RSPI_SPCMD0 + (i) * 2)
50 #define RSPI_NUM_SPCMD		8
51 #define RSPI_RZ_NUM_SPCMD	4
52 #define QSPI_NUM_SPCMD		4
53 
54 /* RSPI on RZ only */
55 #define RSPI_SPBFCR		0x20	/* Buffer Control Register */
56 #define RSPI_SPBFDR		0x22	/* Buffer Data Count Setting Register */
57 
58 /* QSPI only */
59 #define QSPI_SPBFCR		0x18	/* Buffer Control Register */
60 #define QSPI_SPBDCR		0x1a	/* Buffer Data Count Register */
61 #define QSPI_SPBMUL0		0x1c	/* Transfer Data Length Multiplier Setting Register 0 */
62 #define QSPI_SPBMUL1		0x20	/* Transfer Data Length Multiplier Setting Register 1 */
63 #define QSPI_SPBMUL2		0x24	/* Transfer Data Length Multiplier Setting Register 2 */
64 #define QSPI_SPBMUL3		0x28	/* Transfer Data Length Multiplier Setting Register 3 */
65 #define QSPI_SPBMUL(i)		(QSPI_SPBMUL0 + (i) * 4)
66 
67 /* SPCR - Control Register */
68 #define SPCR_SPRIE		0x80	/* Receive Interrupt Enable */
69 #define SPCR_SPE		0x40	/* Function Enable */
70 #define SPCR_SPTIE		0x20	/* Transmit Interrupt Enable */
71 #define SPCR_SPEIE		0x10	/* Error Interrupt Enable */
72 #define SPCR_MSTR		0x08	/* Master/Slave Mode Select */
73 #define SPCR_MODFEN		0x04	/* Mode Fault Error Detection Enable */
74 /* RSPI on SH only */
75 #define SPCR_TXMD		0x02	/* TX Only Mode (vs. Full Duplex) */
76 #define SPCR_SPMS		0x01	/* 3-wire Mode (vs. 4-wire) */
77 /* QSPI on R-Car Gen2 only */
78 #define SPCR_WSWAP		0x02	/* Word Swap of read-data for DMAC */
79 #define SPCR_BSWAP		0x01	/* Byte Swap of read-data for DMAC */
80 
81 /* SSLP - Slave Select Polarity Register */
82 #define SSLP_SSL1P		0x02	/* SSL1 Signal Polarity Setting */
83 #define SSLP_SSL0P		0x01	/* SSL0 Signal Polarity Setting */
84 
85 /* SPPCR - Pin Control Register */
86 #define SPPCR_MOIFE		0x20	/* MOSI Idle Value Fixing Enable */
87 #define SPPCR_MOIFV		0x10	/* MOSI Idle Fixed Value */
88 #define SPPCR_SPOM		0x04
89 #define SPPCR_SPLP2		0x02	/* Loopback Mode 2 (non-inverting) */
90 #define SPPCR_SPLP		0x01	/* Loopback Mode (inverting) */
91 
92 #define SPPCR_IO3FV		0x04	/* Single-/Dual-SPI Mode IO3 Output Fixed Value */
93 #define SPPCR_IO2FV		0x04	/* Single-/Dual-SPI Mode IO2 Output Fixed Value */
94 
95 /* SPSR - Status Register */
96 #define SPSR_SPRF		0x80	/* Receive Buffer Full Flag */
97 #define SPSR_TEND		0x40	/* Transmit End */
98 #define SPSR_SPTEF		0x20	/* Transmit Buffer Empty Flag */
99 #define SPSR_PERF		0x08	/* Parity Error Flag */
100 #define SPSR_MODF		0x04	/* Mode Fault Error Flag */
101 #define SPSR_IDLNF		0x02	/* RSPI Idle Flag */
102 #define SPSR_OVRF		0x01	/* Overrun Error Flag (RSPI only) */
103 
104 /* SPSCR - Sequence Control Register */
105 #define SPSCR_SPSLN_MASK	0x07	/* Sequence Length Specification */
106 
107 /* SPSSR - Sequence Status Register */
108 #define SPSSR_SPECM_MASK	0x70	/* Command Error Mask */
109 #define SPSSR_SPCP_MASK		0x07	/* Command Pointer Mask */
110 
111 /* SPDCR - Data Control Register */
112 #define SPDCR_TXDMY		0x80	/* Dummy Data Transmission Enable */
113 #define SPDCR_SPLW1		0x40	/* Access Width Specification (RZ) */
114 #define SPDCR_SPLW0		0x20	/* Access Width Specification (RZ) */
115 #define SPDCR_SPLLWORD		(SPDCR_SPLW1 | SPDCR_SPLW0)
116 #define SPDCR_SPLWORD		SPDCR_SPLW1
117 #define SPDCR_SPLBYTE		SPDCR_SPLW0
118 #define SPDCR_SPLW		0x20	/* Access Width Specification (SH) */
119 #define SPDCR_SPRDTD		0x10	/* Receive Transmit Data Select (SH) */
120 #define SPDCR_SLSEL1		0x08
121 #define SPDCR_SLSEL0		0x04
122 #define SPDCR_SLSEL_MASK	0x0c	/* SSL1 Output Select (SH) */
123 #define SPDCR_SPFC1		0x02
124 #define SPDCR_SPFC0		0x01
125 #define SPDCR_SPFC_MASK		0x03	/* Frame Count Setting (1-4) (SH) */
126 
127 /* SPCKD - Clock Delay Register */
128 #define SPCKD_SCKDL_MASK	0x07	/* Clock Delay Setting (1-8) */
129 
130 /* SSLND - Slave Select Negation Delay Register */
131 #define SSLND_SLNDL_MASK	0x07	/* SSL Negation Delay Setting (1-8) */
132 
133 /* SPND - Next-Access Delay Register */
134 #define SPND_SPNDL_MASK		0x07	/* Next-Access Delay Setting (1-8) */
135 
136 /* SPCR2 - Control Register 2 */
137 #define SPCR2_PTE		0x08	/* Parity Self-Test Enable */
138 #define SPCR2_SPIE		0x04	/* Idle Interrupt Enable */
139 #define SPCR2_SPOE		0x02	/* Odd Parity Enable (vs. Even) */
140 #define SPCR2_SPPE		0x01	/* Parity Enable */
141 
142 /* SPCMDn - Command Registers */
143 #define SPCMD_SCKDEN		0x8000	/* Clock Delay Setting Enable */
144 #define SPCMD_SLNDEN		0x4000	/* SSL Negation Delay Setting Enable */
145 #define SPCMD_SPNDEN		0x2000	/* Next-Access Delay Enable */
146 #define SPCMD_LSBF		0x1000	/* LSB First */
147 #define SPCMD_SPB_MASK		0x0f00	/* Data Length Setting */
148 #define SPCMD_SPB_8_TO_16(bit)	(((bit - 1) << 8) & SPCMD_SPB_MASK)
149 #define SPCMD_SPB_8BIT		0x0000	/* QSPI only */
150 #define SPCMD_SPB_16BIT		0x0100
151 #define SPCMD_SPB_20BIT		0x0000
152 #define SPCMD_SPB_24BIT		0x0100
153 #define SPCMD_SPB_32BIT		0x0200
154 #define SPCMD_SSLKP		0x0080	/* SSL Signal Level Keeping */
155 #define SPCMD_SPIMOD_MASK	0x0060	/* SPI Operating Mode (QSPI only) */
156 #define SPCMD_SPIMOD1		0x0040
157 #define SPCMD_SPIMOD0		0x0020
158 #define SPCMD_SPIMOD_SINGLE	0
159 #define SPCMD_SPIMOD_DUAL	SPCMD_SPIMOD0
160 #define SPCMD_SPIMOD_QUAD	SPCMD_SPIMOD1
161 #define SPCMD_SPRW		0x0010	/* SPI Read/Write Access (Dual/Quad) */
162 #define SPCMD_SSLA_MASK		0x0030	/* SSL Assert Signal Setting (RSPI) */
163 #define SPCMD_BRDV_MASK		0x000c	/* Bit Rate Division Setting */
164 #define SPCMD_CPOL		0x0002	/* Clock Polarity Setting */
165 #define SPCMD_CPHA		0x0001	/* Clock Phase Setting */
166 
167 /* SPBFCR - Buffer Control Register */
168 #define SPBFCR_TXRST		0x80	/* Transmit Buffer Data Reset */
169 #define SPBFCR_RXRST		0x40	/* Receive Buffer Data Reset */
170 #define SPBFCR_TXTRG_MASK	0x30	/* Transmit Buffer Data Triggering Number */
171 #define SPBFCR_RXTRG_MASK	0x07	/* Receive Buffer Data Triggering Number */
172 /* QSPI on R-Car Gen2 */
173 #define SPBFCR_TXTRG_1B		0x00	/* 31 bytes (1 byte available) */
174 #define SPBFCR_TXTRG_32B	0x30	/* 0 byte (32 bytes available) */
175 #define SPBFCR_RXTRG_1B		0x00	/* 1 byte (31 bytes available) */
176 #define SPBFCR_RXTRG_32B	0x07	/* 32 bytes (0 byte available) */
177 
178 #define QSPI_BUFFER_SIZE        32u
179 
180 struct rspi_data {
181 	void __iomem *addr;
182 	u32 max_speed_hz;
183 	struct spi_master *master;
184 	wait_queue_head_t wait;
185 	struct clk *clk;
186 	u16 spcmd;
187 	u8 spsr;
188 	u8 sppcr;
189 	int rx_irq, tx_irq;
190 	const struct spi_ops *ops;
191 
192 	unsigned dma_callbacked:1;
193 	unsigned byte_access:1;
194 };
195 
196 static void rspi_write8(const struct rspi_data *rspi, u8 data, u16 offset)
197 {
198 	iowrite8(data, rspi->addr + offset);
199 }
200 
201 static void rspi_write16(const struct rspi_data *rspi, u16 data, u16 offset)
202 {
203 	iowrite16(data, rspi->addr + offset);
204 }
205 
206 static void rspi_write32(const struct rspi_data *rspi, u32 data, u16 offset)
207 {
208 	iowrite32(data, rspi->addr + offset);
209 }
210 
211 static u8 rspi_read8(const struct rspi_data *rspi, u16 offset)
212 {
213 	return ioread8(rspi->addr + offset);
214 }
215 
216 static u16 rspi_read16(const struct rspi_data *rspi, u16 offset)
217 {
218 	return ioread16(rspi->addr + offset);
219 }
220 
221 static void rspi_write_data(const struct rspi_data *rspi, u16 data)
222 {
223 	if (rspi->byte_access)
224 		rspi_write8(rspi, data, RSPI_SPDR);
225 	else /* 16 bit */
226 		rspi_write16(rspi, data, RSPI_SPDR);
227 }
228 
229 static u16 rspi_read_data(const struct rspi_data *rspi)
230 {
231 	if (rspi->byte_access)
232 		return rspi_read8(rspi, RSPI_SPDR);
233 	else /* 16 bit */
234 		return rspi_read16(rspi, RSPI_SPDR);
235 }
236 
237 /* optional functions */
238 struct spi_ops {
239 	int (*set_config_register)(struct rspi_data *rspi, int access_size);
240 	int (*transfer_one)(struct spi_master *master, struct spi_device *spi,
241 			    struct spi_transfer *xfer);
242 	u16 mode_bits;
243 	u16 flags;
244 	u16 fifo_size;
245 };
246 
247 /*
248  * functions for RSPI on legacy SH
249  */
250 static int rspi_set_config_register(struct rspi_data *rspi, int access_size)
251 {
252 	int spbr;
253 
254 	/* Sets output mode, MOSI signal, and (optionally) loopback */
255 	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
256 
257 	/* Sets transfer bit rate */
258 	spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk),
259 			    2 * rspi->max_speed_hz) - 1;
260 	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
261 
262 	/* Disable dummy transmission, set 16-bit word access, 1 frame */
263 	rspi_write8(rspi, 0, RSPI_SPDCR);
264 	rspi->byte_access = 0;
265 
266 	/* Sets RSPCK, SSL, next-access delay value */
267 	rspi_write8(rspi, 0x00, RSPI_SPCKD);
268 	rspi_write8(rspi, 0x00, RSPI_SSLND);
269 	rspi_write8(rspi, 0x00, RSPI_SPND);
270 
271 	/* Sets parity, interrupt mask */
272 	rspi_write8(rspi, 0x00, RSPI_SPCR2);
273 
274 	/* Sets SPCMD */
275 	rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size);
276 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
277 
278 	/* Sets RSPI mode */
279 	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
280 
281 	return 0;
282 }
283 
284 /*
285  * functions for RSPI on RZ
286  */
287 static int rspi_rz_set_config_register(struct rspi_data *rspi, int access_size)
288 {
289 	int spbr;
290 	int div = 0;
291 	unsigned long clksrc;
292 
293 	/* Sets output mode, MOSI signal, and (optionally) loopback */
294 	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
295 
296 	clksrc = clk_get_rate(rspi->clk);
297 	while (div < 3) {
298 		if (rspi->max_speed_hz >= clksrc/4) /* 4=(CLK/2)/2 */
299 			break;
300 		div++;
301 		clksrc /= 2;
302 	}
303 
304 	/* Sets transfer bit rate */
305 	spbr = DIV_ROUND_UP(clksrc, 2 * rspi->max_speed_hz) - 1;
306 	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
307 	rspi->spcmd |= div << 2;
308 
309 	/* Disable dummy transmission, set byte access */
310 	rspi_write8(rspi, SPDCR_SPLBYTE, RSPI_SPDCR);
311 	rspi->byte_access = 1;
312 
313 	/* Sets RSPCK, SSL, next-access delay value */
314 	rspi_write8(rspi, 0x00, RSPI_SPCKD);
315 	rspi_write8(rspi, 0x00, RSPI_SSLND);
316 	rspi_write8(rspi, 0x00, RSPI_SPND);
317 
318 	/* Sets SPCMD */
319 	rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size);
320 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
321 
322 	/* Sets RSPI mode */
323 	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
324 
325 	return 0;
326 }
327 
328 /*
329  * functions for QSPI
330  */
331 static int qspi_set_config_register(struct rspi_data *rspi, int access_size)
332 {
333 	int spbr;
334 
335 	/* Sets output mode, MOSI signal, and (optionally) loopback */
336 	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
337 
338 	/* Sets transfer bit rate */
339 	spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk), 2 * rspi->max_speed_hz);
340 	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
341 
342 	/* Disable dummy transmission, set byte access */
343 	rspi_write8(rspi, 0, RSPI_SPDCR);
344 	rspi->byte_access = 1;
345 
346 	/* Sets RSPCK, SSL, next-access delay value */
347 	rspi_write8(rspi, 0x00, RSPI_SPCKD);
348 	rspi_write8(rspi, 0x00, RSPI_SSLND);
349 	rspi_write8(rspi, 0x00, RSPI_SPND);
350 
351 	/* Data Length Setting */
352 	if (access_size == 8)
353 		rspi->spcmd |= SPCMD_SPB_8BIT;
354 	else if (access_size == 16)
355 		rspi->spcmd |= SPCMD_SPB_16BIT;
356 	else
357 		rspi->spcmd |= SPCMD_SPB_32BIT;
358 
359 	rspi->spcmd |= SPCMD_SCKDEN | SPCMD_SLNDEN | SPCMD_SPNDEN;
360 
361 	/* Resets transfer data length */
362 	rspi_write32(rspi, 0, QSPI_SPBMUL0);
363 
364 	/* Resets transmit and receive buffer */
365 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
366 	/* Sets buffer to allow normal operation */
367 	rspi_write8(rspi, 0x00, QSPI_SPBFCR);
368 
369 	/* Sets SPCMD */
370 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
371 
372 	/* Sets RSPI mode */
373 	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
374 
375 	return 0;
376 }
377 
378 static void qspi_update(const struct rspi_data *rspi, u8 mask, u8 val, u8 reg)
379 {
380 	u8 data;
381 
382 	data = rspi_read8(rspi, reg);
383 	data &= ~mask;
384 	data |= (val & mask);
385 	rspi_write8(rspi, data, reg);
386 }
387 
388 static unsigned int qspi_set_send_trigger(struct rspi_data *rspi,
389 					  unsigned int len)
390 {
391 	unsigned int n;
392 
393 	n = min(len, QSPI_BUFFER_SIZE);
394 
395 	if (len >= QSPI_BUFFER_SIZE) {
396 		/* sets triggering number to 32 bytes */
397 		qspi_update(rspi, SPBFCR_TXTRG_MASK,
398 			     SPBFCR_TXTRG_32B, QSPI_SPBFCR);
399 	} else {
400 		/* sets triggering number to 1 byte */
401 		qspi_update(rspi, SPBFCR_TXTRG_MASK,
402 			     SPBFCR_TXTRG_1B, QSPI_SPBFCR);
403 	}
404 
405 	return n;
406 }
407 
408 static int qspi_set_receive_trigger(struct rspi_data *rspi, unsigned int len)
409 {
410 	unsigned int n;
411 
412 	n = min(len, QSPI_BUFFER_SIZE);
413 
414 	if (len >= QSPI_BUFFER_SIZE) {
415 		/* sets triggering number to 32 bytes */
416 		qspi_update(rspi, SPBFCR_RXTRG_MASK,
417 			     SPBFCR_RXTRG_32B, QSPI_SPBFCR);
418 	} else {
419 		/* sets triggering number to 1 byte */
420 		qspi_update(rspi, SPBFCR_RXTRG_MASK,
421 			     SPBFCR_RXTRG_1B, QSPI_SPBFCR);
422 	}
423 	return n;
424 }
425 
426 #define set_config_register(spi, n) spi->ops->set_config_register(spi, n)
427 
428 static void rspi_enable_irq(const struct rspi_data *rspi, u8 enable)
429 {
430 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | enable, RSPI_SPCR);
431 }
432 
433 static void rspi_disable_irq(const struct rspi_data *rspi, u8 disable)
434 {
435 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~disable, RSPI_SPCR);
436 }
437 
438 static int rspi_wait_for_interrupt(struct rspi_data *rspi, u8 wait_mask,
439 				   u8 enable_bit)
440 {
441 	int ret;
442 
443 	rspi->spsr = rspi_read8(rspi, RSPI_SPSR);
444 	if (rspi->spsr & wait_mask)
445 		return 0;
446 
447 	rspi_enable_irq(rspi, enable_bit);
448 	ret = wait_event_timeout(rspi->wait, rspi->spsr & wait_mask, HZ);
449 	if (ret == 0 && !(rspi->spsr & wait_mask))
450 		return -ETIMEDOUT;
451 
452 	return 0;
453 }
454 
455 static inline int rspi_wait_for_tx_empty(struct rspi_data *rspi)
456 {
457 	return rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
458 }
459 
460 static inline int rspi_wait_for_rx_full(struct rspi_data *rspi)
461 {
462 	return rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE);
463 }
464 
465 static int rspi_data_out(struct rspi_data *rspi, u8 data)
466 {
467 	int error = rspi_wait_for_tx_empty(rspi);
468 	if (error < 0) {
469 		dev_err(&rspi->master->dev, "transmit timeout\n");
470 		return error;
471 	}
472 	rspi_write_data(rspi, data);
473 	return 0;
474 }
475 
476 static int rspi_data_in(struct rspi_data *rspi)
477 {
478 	int error;
479 	u8 data;
480 
481 	error = rspi_wait_for_rx_full(rspi);
482 	if (error < 0) {
483 		dev_err(&rspi->master->dev, "receive timeout\n");
484 		return error;
485 	}
486 	data = rspi_read_data(rspi);
487 	return data;
488 }
489 
490 static int rspi_pio_transfer(struct rspi_data *rspi, const u8 *tx, u8 *rx,
491 			     unsigned int n)
492 {
493 	while (n-- > 0) {
494 		if (tx) {
495 			int ret = rspi_data_out(rspi, *tx++);
496 			if (ret < 0)
497 				return ret;
498 		}
499 		if (rx) {
500 			int ret = rspi_data_in(rspi);
501 			if (ret < 0)
502 				return ret;
503 			*rx++ = ret;
504 		}
505 	}
506 
507 	return 0;
508 }
509 
510 static void rspi_dma_complete(void *arg)
511 {
512 	struct rspi_data *rspi = arg;
513 
514 	rspi->dma_callbacked = 1;
515 	wake_up_interruptible(&rspi->wait);
516 }
517 
518 static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
519 			     struct sg_table *rx)
520 {
521 	struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL;
522 	u8 irq_mask = 0;
523 	unsigned int other_irq = 0;
524 	dma_cookie_t cookie;
525 	int ret;
526 
527 	/* First prepare and submit the DMA request(s), as this may fail */
528 	if (rx) {
529 		desc_rx = dmaengine_prep_slave_sg(rspi->master->dma_rx,
530 					rx->sgl, rx->nents, DMA_DEV_TO_MEM,
531 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
532 		if (!desc_rx) {
533 			ret = -EAGAIN;
534 			goto no_dma_rx;
535 		}
536 
537 		desc_rx->callback = rspi_dma_complete;
538 		desc_rx->callback_param = rspi;
539 		cookie = dmaengine_submit(desc_rx);
540 		if (dma_submit_error(cookie)) {
541 			ret = cookie;
542 			goto no_dma_rx;
543 		}
544 
545 		irq_mask |= SPCR_SPRIE;
546 	}
547 
548 	if (tx) {
549 		desc_tx = dmaengine_prep_slave_sg(rspi->master->dma_tx,
550 					tx->sgl, tx->nents, DMA_MEM_TO_DEV,
551 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
552 		if (!desc_tx) {
553 			ret = -EAGAIN;
554 			goto no_dma_tx;
555 		}
556 
557 		if (rx) {
558 			/* No callback */
559 			desc_tx->callback = NULL;
560 		} else {
561 			desc_tx->callback = rspi_dma_complete;
562 			desc_tx->callback_param = rspi;
563 		}
564 		cookie = dmaengine_submit(desc_tx);
565 		if (dma_submit_error(cookie)) {
566 			ret = cookie;
567 			goto no_dma_tx;
568 		}
569 
570 		irq_mask |= SPCR_SPTIE;
571 	}
572 
573 	/*
574 	 * DMAC needs SPxIE, but if SPxIE is set, the IRQ routine will be
575 	 * called. So, this driver disables the IRQ while DMA transfer.
576 	 */
577 	if (tx)
578 		disable_irq(other_irq = rspi->tx_irq);
579 	if (rx && rspi->rx_irq != other_irq)
580 		disable_irq(rspi->rx_irq);
581 
582 	rspi_enable_irq(rspi, irq_mask);
583 	rspi->dma_callbacked = 0;
584 
585 	/* Now start DMA */
586 	if (rx)
587 		dma_async_issue_pending(rspi->master->dma_rx);
588 	if (tx)
589 		dma_async_issue_pending(rspi->master->dma_tx);
590 
591 	ret = wait_event_interruptible_timeout(rspi->wait,
592 					       rspi->dma_callbacked, HZ);
593 	if (ret > 0 && rspi->dma_callbacked) {
594 		ret = 0;
595 	} else {
596 		if (!ret) {
597 			dev_err(&rspi->master->dev, "DMA timeout\n");
598 			ret = -ETIMEDOUT;
599 		}
600 		if (tx)
601 			dmaengine_terminate_all(rspi->master->dma_tx);
602 		if (rx)
603 			dmaengine_terminate_all(rspi->master->dma_rx);
604 	}
605 
606 	rspi_disable_irq(rspi, irq_mask);
607 
608 	if (tx)
609 		enable_irq(rspi->tx_irq);
610 	if (rx && rspi->rx_irq != other_irq)
611 		enable_irq(rspi->rx_irq);
612 
613 	return ret;
614 
615 no_dma_tx:
616 	if (rx)
617 		dmaengine_terminate_all(rspi->master->dma_rx);
618 no_dma_rx:
619 	if (ret == -EAGAIN) {
620 		pr_warn_once("%s %s: DMA not available, falling back to PIO\n",
621 			     dev_driver_string(&rspi->master->dev),
622 			     dev_name(&rspi->master->dev));
623 	}
624 	return ret;
625 }
626 
627 static void rspi_receive_init(const struct rspi_data *rspi)
628 {
629 	u8 spsr;
630 
631 	spsr = rspi_read8(rspi, RSPI_SPSR);
632 	if (spsr & SPSR_SPRF)
633 		rspi_read_data(rspi);	/* dummy read */
634 	if (spsr & SPSR_OVRF)
635 		rspi_write8(rspi, rspi_read8(rspi, RSPI_SPSR) & ~SPSR_OVRF,
636 			    RSPI_SPSR);
637 }
638 
639 static void rspi_rz_receive_init(const struct rspi_data *rspi)
640 {
641 	rspi_receive_init(rspi);
642 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, RSPI_SPBFCR);
643 	rspi_write8(rspi, 0, RSPI_SPBFCR);
644 }
645 
646 static void qspi_receive_init(const struct rspi_data *rspi)
647 {
648 	u8 spsr;
649 
650 	spsr = rspi_read8(rspi, RSPI_SPSR);
651 	if (spsr & SPSR_SPRF)
652 		rspi_read_data(rspi);   /* dummy read */
653 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
654 	rspi_write8(rspi, 0, QSPI_SPBFCR);
655 }
656 
657 static bool __rspi_can_dma(const struct rspi_data *rspi,
658 			   const struct spi_transfer *xfer)
659 {
660 	return xfer->len > rspi->ops->fifo_size;
661 }
662 
663 static bool rspi_can_dma(struct spi_master *master, struct spi_device *spi,
664 			 struct spi_transfer *xfer)
665 {
666 	struct rspi_data *rspi = spi_master_get_devdata(master);
667 
668 	return __rspi_can_dma(rspi, xfer);
669 }
670 
671 static int rspi_dma_check_then_transfer(struct rspi_data *rspi,
672 					 struct spi_transfer *xfer)
673 {
674 	if (!rspi->master->can_dma || !__rspi_can_dma(rspi, xfer))
675 		return -EAGAIN;
676 
677 	/* rx_buf can be NULL on RSPI on SH in TX-only Mode */
678 	return rspi_dma_transfer(rspi, &xfer->tx_sg,
679 				xfer->rx_buf ? &xfer->rx_sg : NULL);
680 }
681 
682 static int rspi_common_transfer(struct rspi_data *rspi,
683 				struct spi_transfer *xfer)
684 {
685 	int ret;
686 
687 	ret = rspi_dma_check_then_transfer(rspi, xfer);
688 	if (ret != -EAGAIN)
689 		return ret;
690 
691 	ret = rspi_pio_transfer(rspi, xfer->tx_buf, xfer->rx_buf, xfer->len);
692 	if (ret < 0)
693 		return ret;
694 
695 	/* Wait for the last transmission */
696 	rspi_wait_for_tx_empty(rspi);
697 
698 	return 0;
699 }
700 
701 static int rspi_transfer_one(struct spi_master *master, struct spi_device *spi,
702 			     struct spi_transfer *xfer)
703 {
704 	struct rspi_data *rspi = spi_master_get_devdata(master);
705 	u8 spcr;
706 
707 	spcr = rspi_read8(rspi, RSPI_SPCR);
708 	if (xfer->rx_buf) {
709 		rspi_receive_init(rspi);
710 		spcr &= ~SPCR_TXMD;
711 	} else {
712 		spcr |= SPCR_TXMD;
713 	}
714 	rspi_write8(rspi, spcr, RSPI_SPCR);
715 
716 	return rspi_common_transfer(rspi, xfer);
717 }
718 
719 static int rspi_rz_transfer_one(struct spi_master *master,
720 				struct spi_device *spi,
721 				struct spi_transfer *xfer)
722 {
723 	struct rspi_data *rspi = spi_master_get_devdata(master);
724 
725 	rspi_rz_receive_init(rspi);
726 
727 	return rspi_common_transfer(rspi, xfer);
728 }
729 
730 static int qspi_trigger_transfer_out_in(struct rspi_data *rspi, const u8 *tx,
731 					u8 *rx, unsigned int len)
732 {
733 	unsigned int i, n;
734 	int ret;
735 
736 	while (len > 0) {
737 		n = qspi_set_send_trigger(rspi, len);
738 		qspi_set_receive_trigger(rspi, len);
739 		if (n == QSPI_BUFFER_SIZE) {
740 			ret = rspi_wait_for_tx_empty(rspi);
741 			if (ret < 0) {
742 				dev_err(&rspi->master->dev, "transmit timeout\n");
743 				return ret;
744 			}
745 			for (i = 0; i < n; i++)
746 				rspi_write_data(rspi, *tx++);
747 
748 			ret = rspi_wait_for_rx_full(rspi);
749 			if (ret < 0) {
750 				dev_err(&rspi->master->dev, "receive timeout\n");
751 				return ret;
752 			}
753 			for (i = 0; i < n; i++)
754 				*rx++ = rspi_read_data(rspi);
755 		} else {
756 			ret = rspi_pio_transfer(rspi, tx, rx, n);
757 			if (ret < 0)
758 				return ret;
759 		}
760 		len -= n;
761 	}
762 
763 	return 0;
764 }
765 
766 static int qspi_transfer_out_in(struct rspi_data *rspi,
767 				struct spi_transfer *xfer)
768 {
769 	int ret;
770 
771 	qspi_receive_init(rspi);
772 
773 	ret = rspi_dma_check_then_transfer(rspi, xfer);
774 	if (ret != -EAGAIN)
775 		return ret;
776 
777 	return qspi_trigger_transfer_out_in(rspi, xfer->tx_buf,
778 					    xfer->rx_buf, xfer->len);
779 }
780 
781 static int qspi_transfer_out(struct rspi_data *rspi, struct spi_transfer *xfer)
782 {
783 	const u8 *tx = xfer->tx_buf;
784 	unsigned int n = xfer->len;
785 	unsigned int i, len;
786 	int ret;
787 
788 	if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer)) {
789 		ret = rspi_dma_transfer(rspi, &xfer->tx_sg, NULL);
790 		if (ret != -EAGAIN)
791 			return ret;
792 	}
793 
794 	while (n > 0) {
795 		len = qspi_set_send_trigger(rspi, n);
796 		if (len == QSPI_BUFFER_SIZE) {
797 			ret = rspi_wait_for_tx_empty(rspi);
798 			if (ret < 0) {
799 				dev_err(&rspi->master->dev, "transmit timeout\n");
800 				return ret;
801 			}
802 			for (i = 0; i < len; i++)
803 				rspi_write_data(rspi, *tx++);
804 		} else {
805 			ret = rspi_pio_transfer(rspi, tx, NULL, len);
806 			if (ret < 0)
807 				return ret;
808 		}
809 		n -= len;
810 	}
811 
812 	/* Wait for the last transmission */
813 	rspi_wait_for_tx_empty(rspi);
814 
815 	return 0;
816 }
817 
818 static int qspi_transfer_in(struct rspi_data *rspi, struct spi_transfer *xfer)
819 {
820 	u8 *rx = xfer->rx_buf;
821 	unsigned int n = xfer->len;
822 	unsigned int i, len;
823 	int ret;
824 
825 	if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer)) {
826 		int ret = rspi_dma_transfer(rspi, NULL, &xfer->rx_sg);
827 		if (ret != -EAGAIN)
828 			return ret;
829 	}
830 
831 	while (n > 0) {
832 		len = qspi_set_receive_trigger(rspi, n);
833 		if (len == QSPI_BUFFER_SIZE) {
834 			ret = rspi_wait_for_rx_full(rspi);
835 			if (ret < 0) {
836 				dev_err(&rspi->master->dev, "receive timeout\n");
837 				return ret;
838 			}
839 			for (i = 0; i < len; i++)
840 				*rx++ = rspi_read_data(rspi);
841 		} else {
842 			ret = rspi_pio_transfer(rspi, NULL, rx, len);
843 			if (ret < 0)
844 				return ret;
845 		}
846 		n -= len;
847 	}
848 
849 	return 0;
850 }
851 
852 static int qspi_transfer_one(struct spi_master *master, struct spi_device *spi,
853 			     struct spi_transfer *xfer)
854 {
855 	struct rspi_data *rspi = spi_master_get_devdata(master);
856 
857 	if (spi->mode & SPI_LOOP) {
858 		return qspi_transfer_out_in(rspi, xfer);
859 	} else if (xfer->tx_nbits > SPI_NBITS_SINGLE) {
860 		/* Quad or Dual SPI Write */
861 		return qspi_transfer_out(rspi, xfer);
862 	} else if (xfer->rx_nbits > SPI_NBITS_SINGLE) {
863 		/* Quad or Dual SPI Read */
864 		return qspi_transfer_in(rspi, xfer);
865 	} else {
866 		/* Single SPI Transfer */
867 		return qspi_transfer_out_in(rspi, xfer);
868 	}
869 }
870 
871 static int rspi_setup(struct spi_device *spi)
872 {
873 	struct rspi_data *rspi = spi_master_get_devdata(spi->master);
874 
875 	rspi->max_speed_hz = spi->max_speed_hz;
876 
877 	rspi->spcmd = SPCMD_SSLKP;
878 	if (spi->mode & SPI_CPOL)
879 		rspi->spcmd |= SPCMD_CPOL;
880 	if (spi->mode & SPI_CPHA)
881 		rspi->spcmd |= SPCMD_CPHA;
882 
883 	/* CMOS output mode and MOSI signal from previous transfer */
884 	rspi->sppcr = 0;
885 	if (spi->mode & SPI_LOOP)
886 		rspi->sppcr |= SPPCR_SPLP;
887 
888 	set_config_register(rspi, 8);
889 
890 	return 0;
891 }
892 
893 static u16 qspi_transfer_mode(const struct spi_transfer *xfer)
894 {
895 	if (xfer->tx_buf)
896 		switch (xfer->tx_nbits) {
897 		case SPI_NBITS_QUAD:
898 			return SPCMD_SPIMOD_QUAD;
899 		case SPI_NBITS_DUAL:
900 			return SPCMD_SPIMOD_DUAL;
901 		default:
902 			return 0;
903 		}
904 	if (xfer->rx_buf)
905 		switch (xfer->rx_nbits) {
906 		case SPI_NBITS_QUAD:
907 			return SPCMD_SPIMOD_QUAD | SPCMD_SPRW;
908 		case SPI_NBITS_DUAL:
909 			return SPCMD_SPIMOD_DUAL | SPCMD_SPRW;
910 		default:
911 			return 0;
912 		}
913 
914 	return 0;
915 }
916 
917 static int qspi_setup_sequencer(struct rspi_data *rspi,
918 				const struct spi_message *msg)
919 {
920 	const struct spi_transfer *xfer;
921 	unsigned int i = 0, len = 0;
922 	u16 current_mode = 0xffff, mode;
923 
924 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
925 		mode = qspi_transfer_mode(xfer);
926 		if (mode == current_mode) {
927 			len += xfer->len;
928 			continue;
929 		}
930 
931 		/* Transfer mode change */
932 		if (i) {
933 			/* Set transfer data length of previous transfer */
934 			rspi_write32(rspi, len, QSPI_SPBMUL(i - 1));
935 		}
936 
937 		if (i >= QSPI_NUM_SPCMD) {
938 			dev_err(&msg->spi->dev,
939 				"Too many different transfer modes");
940 			return -EINVAL;
941 		}
942 
943 		/* Program transfer mode for this transfer */
944 		rspi_write16(rspi, rspi->spcmd | mode, RSPI_SPCMD(i));
945 		current_mode = mode;
946 		len = xfer->len;
947 		i++;
948 	}
949 	if (i) {
950 		/* Set final transfer data length and sequence length */
951 		rspi_write32(rspi, len, QSPI_SPBMUL(i - 1));
952 		rspi_write8(rspi, i - 1, RSPI_SPSCR);
953 	}
954 
955 	return 0;
956 }
957 
958 static int rspi_prepare_message(struct spi_master *master,
959 				struct spi_message *msg)
960 {
961 	struct rspi_data *rspi = spi_master_get_devdata(master);
962 	int ret;
963 
964 	if (msg->spi->mode &
965 	    (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD)) {
966 		/* Setup sequencer for messages with multiple transfer modes */
967 		ret = qspi_setup_sequencer(rspi, msg);
968 		if (ret < 0)
969 			return ret;
970 	}
971 
972 	/* Enable SPI function in master mode */
973 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_SPE, RSPI_SPCR);
974 	return 0;
975 }
976 
977 static int rspi_unprepare_message(struct spi_master *master,
978 				  struct spi_message *msg)
979 {
980 	struct rspi_data *rspi = spi_master_get_devdata(master);
981 
982 	/* Disable SPI function */
983 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_SPE, RSPI_SPCR);
984 
985 	/* Reset sequencer for Single SPI Transfers */
986 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
987 	rspi_write8(rspi, 0, RSPI_SPSCR);
988 	return 0;
989 }
990 
991 static irqreturn_t rspi_irq_mux(int irq, void *_sr)
992 {
993 	struct rspi_data *rspi = _sr;
994 	u8 spsr;
995 	irqreturn_t ret = IRQ_NONE;
996 	u8 disable_irq = 0;
997 
998 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
999 	if (spsr & SPSR_SPRF)
1000 		disable_irq |= SPCR_SPRIE;
1001 	if (spsr & SPSR_SPTEF)
1002 		disable_irq |= SPCR_SPTIE;
1003 
1004 	if (disable_irq) {
1005 		ret = IRQ_HANDLED;
1006 		rspi_disable_irq(rspi, disable_irq);
1007 		wake_up(&rspi->wait);
1008 	}
1009 
1010 	return ret;
1011 }
1012 
1013 static irqreturn_t rspi_irq_rx(int irq, void *_sr)
1014 {
1015 	struct rspi_data *rspi = _sr;
1016 	u8 spsr;
1017 
1018 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
1019 	if (spsr & SPSR_SPRF) {
1020 		rspi_disable_irq(rspi, SPCR_SPRIE);
1021 		wake_up(&rspi->wait);
1022 		return IRQ_HANDLED;
1023 	}
1024 
1025 	return 0;
1026 }
1027 
1028 static irqreturn_t rspi_irq_tx(int irq, void *_sr)
1029 {
1030 	struct rspi_data *rspi = _sr;
1031 	u8 spsr;
1032 
1033 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
1034 	if (spsr & SPSR_SPTEF) {
1035 		rspi_disable_irq(rspi, SPCR_SPTIE);
1036 		wake_up(&rspi->wait);
1037 		return IRQ_HANDLED;
1038 	}
1039 
1040 	return 0;
1041 }
1042 
1043 static struct dma_chan *rspi_request_dma_chan(struct device *dev,
1044 					      enum dma_transfer_direction dir,
1045 					      unsigned int id,
1046 					      dma_addr_t port_addr)
1047 {
1048 	dma_cap_mask_t mask;
1049 	struct dma_chan *chan;
1050 	struct dma_slave_config cfg;
1051 	int ret;
1052 
1053 	dma_cap_zero(mask);
1054 	dma_cap_set(DMA_SLAVE, mask);
1055 
1056 	chan = dma_request_slave_channel_compat(mask, shdma_chan_filter,
1057 				(void *)(unsigned long)id, dev,
1058 				dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1059 	if (!chan) {
1060 		dev_warn(dev, "dma_request_slave_channel_compat failed\n");
1061 		return NULL;
1062 	}
1063 
1064 	memset(&cfg, 0, sizeof(cfg));
1065 	cfg.direction = dir;
1066 	if (dir == DMA_MEM_TO_DEV) {
1067 		cfg.dst_addr = port_addr;
1068 		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1069 	} else {
1070 		cfg.src_addr = port_addr;
1071 		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1072 	}
1073 
1074 	ret = dmaengine_slave_config(chan, &cfg);
1075 	if (ret) {
1076 		dev_warn(dev, "dmaengine_slave_config failed %d\n", ret);
1077 		dma_release_channel(chan);
1078 		return NULL;
1079 	}
1080 
1081 	return chan;
1082 }
1083 
1084 static int rspi_request_dma(struct device *dev, struct spi_master *master,
1085 			    const struct resource *res)
1086 {
1087 	const struct rspi_plat_data *rspi_pd = dev_get_platdata(dev);
1088 	unsigned int dma_tx_id, dma_rx_id;
1089 
1090 	if (dev->of_node) {
1091 		/* In the OF case we will get the slave IDs from the DT */
1092 		dma_tx_id = 0;
1093 		dma_rx_id = 0;
1094 	} else if (rspi_pd && rspi_pd->dma_tx_id && rspi_pd->dma_rx_id) {
1095 		dma_tx_id = rspi_pd->dma_tx_id;
1096 		dma_rx_id = rspi_pd->dma_rx_id;
1097 	} else {
1098 		/* The driver assumes no error. */
1099 		return 0;
1100 	}
1101 
1102 	master->dma_tx = rspi_request_dma_chan(dev, DMA_MEM_TO_DEV, dma_tx_id,
1103 					       res->start + RSPI_SPDR);
1104 	if (!master->dma_tx)
1105 		return -ENODEV;
1106 
1107 	master->dma_rx = rspi_request_dma_chan(dev, DMA_DEV_TO_MEM, dma_rx_id,
1108 					       res->start + RSPI_SPDR);
1109 	if (!master->dma_rx) {
1110 		dma_release_channel(master->dma_tx);
1111 		master->dma_tx = NULL;
1112 		return -ENODEV;
1113 	}
1114 
1115 	master->can_dma = rspi_can_dma;
1116 	dev_info(dev, "DMA available");
1117 	return 0;
1118 }
1119 
1120 static void rspi_release_dma(struct spi_master *master)
1121 {
1122 	if (master->dma_tx)
1123 		dma_release_channel(master->dma_tx);
1124 	if (master->dma_rx)
1125 		dma_release_channel(master->dma_rx);
1126 }
1127 
1128 static int rspi_remove(struct platform_device *pdev)
1129 {
1130 	struct rspi_data *rspi = platform_get_drvdata(pdev);
1131 
1132 	rspi_release_dma(rspi->master);
1133 	pm_runtime_disable(&pdev->dev);
1134 
1135 	return 0;
1136 }
1137 
1138 static const struct spi_ops rspi_ops = {
1139 	.set_config_register =	rspi_set_config_register,
1140 	.transfer_one =		rspi_transfer_one,
1141 	.mode_bits =		SPI_CPHA | SPI_CPOL | SPI_LOOP,
1142 	.flags =		SPI_MASTER_MUST_TX,
1143 	.fifo_size =		8,
1144 };
1145 
1146 static const struct spi_ops rspi_rz_ops = {
1147 	.set_config_register =	rspi_rz_set_config_register,
1148 	.transfer_one =		rspi_rz_transfer_one,
1149 	.mode_bits =		SPI_CPHA | SPI_CPOL | SPI_LOOP,
1150 	.flags =		SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX,
1151 	.fifo_size =		8,	/* 8 for TX, 32 for RX */
1152 };
1153 
1154 static const struct spi_ops qspi_ops = {
1155 	.set_config_register =	qspi_set_config_register,
1156 	.transfer_one =		qspi_transfer_one,
1157 	.mode_bits =		SPI_CPHA | SPI_CPOL | SPI_LOOP |
1158 				SPI_TX_DUAL | SPI_TX_QUAD |
1159 				SPI_RX_DUAL | SPI_RX_QUAD,
1160 	.flags =		SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX,
1161 	.fifo_size =		32,
1162 };
1163 
1164 #ifdef CONFIG_OF
1165 static const struct of_device_id rspi_of_match[] = {
1166 	/* RSPI on legacy SH */
1167 	{ .compatible = "renesas,rspi", .data = &rspi_ops },
1168 	/* RSPI on RZ/A1H */
1169 	{ .compatible = "renesas,rspi-rz", .data = &rspi_rz_ops },
1170 	/* QSPI on R-Car Gen2 */
1171 	{ .compatible = "renesas,qspi", .data = &qspi_ops },
1172 	{ /* sentinel */ }
1173 };
1174 
1175 MODULE_DEVICE_TABLE(of, rspi_of_match);
1176 
1177 static int rspi_parse_dt(struct device *dev, struct spi_master *master)
1178 {
1179 	u32 num_cs;
1180 	int error;
1181 
1182 	/* Parse DT properties */
1183 	error = of_property_read_u32(dev->of_node, "num-cs", &num_cs);
1184 	if (error) {
1185 		dev_err(dev, "of_property_read_u32 num-cs failed %d\n", error);
1186 		return error;
1187 	}
1188 
1189 	master->num_chipselect = num_cs;
1190 	return 0;
1191 }
1192 #else
1193 #define rspi_of_match	NULL
1194 static inline int rspi_parse_dt(struct device *dev, struct spi_master *master)
1195 {
1196 	return -EINVAL;
1197 }
1198 #endif /* CONFIG_OF */
1199 
1200 static int rspi_request_irq(struct device *dev, unsigned int irq,
1201 			    irq_handler_t handler, const char *suffix,
1202 			    void *dev_id)
1203 {
1204 	const char *name = devm_kasprintf(dev, GFP_KERNEL, "%s:%s",
1205 					  dev_name(dev), suffix);
1206 	if (!name)
1207 		return -ENOMEM;
1208 
1209 	return devm_request_irq(dev, irq, handler, 0, name, dev_id);
1210 }
1211 
1212 static int rspi_probe(struct platform_device *pdev)
1213 {
1214 	struct resource *res;
1215 	struct spi_master *master;
1216 	struct rspi_data *rspi;
1217 	int ret;
1218 	const struct rspi_plat_data *rspi_pd;
1219 	const struct spi_ops *ops;
1220 
1221 	master = spi_alloc_master(&pdev->dev, sizeof(struct rspi_data));
1222 	if (master == NULL)
1223 		return -ENOMEM;
1224 
1225 	ops = of_device_get_match_data(&pdev->dev);
1226 	if (ops) {
1227 		ret = rspi_parse_dt(&pdev->dev, master);
1228 		if (ret)
1229 			goto error1;
1230 	} else {
1231 		ops = (struct spi_ops *)pdev->id_entry->driver_data;
1232 		rspi_pd = dev_get_platdata(&pdev->dev);
1233 		if (rspi_pd && rspi_pd->num_chipselect)
1234 			master->num_chipselect = rspi_pd->num_chipselect;
1235 		else
1236 			master->num_chipselect = 2; /* default */
1237 	}
1238 
1239 	/* ops parameter check */
1240 	if (!ops->set_config_register) {
1241 		dev_err(&pdev->dev, "there is no set_config_register\n");
1242 		ret = -ENODEV;
1243 		goto error1;
1244 	}
1245 
1246 	rspi = spi_master_get_devdata(master);
1247 	platform_set_drvdata(pdev, rspi);
1248 	rspi->ops = ops;
1249 	rspi->master = master;
1250 
1251 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1252 	rspi->addr = devm_ioremap_resource(&pdev->dev, res);
1253 	if (IS_ERR(rspi->addr)) {
1254 		ret = PTR_ERR(rspi->addr);
1255 		goto error1;
1256 	}
1257 
1258 	rspi->clk = devm_clk_get(&pdev->dev, NULL);
1259 	if (IS_ERR(rspi->clk)) {
1260 		dev_err(&pdev->dev, "cannot get clock\n");
1261 		ret = PTR_ERR(rspi->clk);
1262 		goto error1;
1263 	}
1264 
1265 	pm_runtime_enable(&pdev->dev);
1266 
1267 	init_waitqueue_head(&rspi->wait);
1268 
1269 	master->bus_num = pdev->id;
1270 	master->setup = rspi_setup;
1271 	master->auto_runtime_pm = true;
1272 	master->transfer_one = ops->transfer_one;
1273 	master->prepare_message = rspi_prepare_message;
1274 	master->unprepare_message = rspi_unprepare_message;
1275 	master->mode_bits = ops->mode_bits;
1276 	master->flags = ops->flags;
1277 	master->dev.of_node = pdev->dev.of_node;
1278 
1279 	ret = platform_get_irq_byname(pdev, "rx");
1280 	if (ret < 0) {
1281 		ret = platform_get_irq_byname(pdev, "mux");
1282 		if (ret < 0)
1283 			ret = platform_get_irq(pdev, 0);
1284 		if (ret >= 0)
1285 			rspi->rx_irq = rspi->tx_irq = ret;
1286 	} else {
1287 		rspi->rx_irq = ret;
1288 		ret = platform_get_irq_byname(pdev, "tx");
1289 		if (ret >= 0)
1290 			rspi->tx_irq = ret;
1291 	}
1292 	if (ret < 0) {
1293 		dev_err(&pdev->dev, "platform_get_irq error\n");
1294 		goto error2;
1295 	}
1296 
1297 	if (rspi->rx_irq == rspi->tx_irq) {
1298 		/* Single multiplexed interrupt */
1299 		ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_mux,
1300 				       "mux", rspi);
1301 	} else {
1302 		/* Multi-interrupt mode, only SPRI and SPTI are used */
1303 		ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_rx,
1304 				       "rx", rspi);
1305 		if (!ret)
1306 			ret = rspi_request_irq(&pdev->dev, rspi->tx_irq,
1307 					       rspi_irq_tx, "tx", rspi);
1308 	}
1309 	if (ret < 0) {
1310 		dev_err(&pdev->dev, "request_irq error\n");
1311 		goto error2;
1312 	}
1313 
1314 	ret = rspi_request_dma(&pdev->dev, master, res);
1315 	if (ret < 0)
1316 		dev_warn(&pdev->dev, "DMA not available, using PIO\n");
1317 
1318 	ret = devm_spi_register_master(&pdev->dev, master);
1319 	if (ret < 0) {
1320 		dev_err(&pdev->dev, "spi_register_master error.\n");
1321 		goto error3;
1322 	}
1323 
1324 	dev_info(&pdev->dev, "probed\n");
1325 
1326 	return 0;
1327 
1328 error3:
1329 	rspi_release_dma(master);
1330 error2:
1331 	pm_runtime_disable(&pdev->dev);
1332 error1:
1333 	spi_master_put(master);
1334 
1335 	return ret;
1336 }
1337 
1338 static const struct platform_device_id spi_driver_ids[] = {
1339 	{ "rspi",	(kernel_ulong_t)&rspi_ops },
1340 	{ "rspi-rz",	(kernel_ulong_t)&rspi_rz_ops },
1341 	{ "qspi",	(kernel_ulong_t)&qspi_ops },
1342 	{},
1343 };
1344 
1345 MODULE_DEVICE_TABLE(platform, spi_driver_ids);
1346 
1347 #ifdef CONFIG_PM_SLEEP
1348 static int rspi_suspend(struct device *dev)
1349 {
1350 	struct platform_device *pdev = to_platform_device(dev);
1351 	struct rspi_data *rspi = platform_get_drvdata(pdev);
1352 
1353 	return spi_master_suspend(rspi->master);
1354 }
1355 
1356 static int rspi_resume(struct device *dev)
1357 {
1358 	struct platform_device *pdev = to_platform_device(dev);
1359 	struct rspi_data *rspi = platform_get_drvdata(pdev);
1360 
1361 	return spi_master_resume(rspi->master);
1362 }
1363 
1364 static SIMPLE_DEV_PM_OPS(rspi_pm_ops, rspi_suspend, rspi_resume);
1365 #define DEV_PM_OPS	&rspi_pm_ops
1366 #else
1367 #define DEV_PM_OPS	NULL
1368 #endif /* CONFIG_PM_SLEEP */
1369 
1370 static struct platform_driver rspi_driver = {
1371 	.probe =	rspi_probe,
1372 	.remove =	rspi_remove,
1373 	.id_table =	spi_driver_ids,
1374 	.driver		= {
1375 		.name = "renesas_spi",
1376 		.pm = DEV_PM_OPS,
1377 		.of_match_table = of_match_ptr(rspi_of_match),
1378 	},
1379 };
1380 module_platform_driver(rspi_driver);
1381 
1382 MODULE_DESCRIPTION("Renesas RSPI bus driver");
1383 MODULE_LICENSE("GPL v2");
1384 MODULE_AUTHOR("Yoshihiro Shimoda");
1385 MODULE_ALIAS("platform:rspi");
1386