xref: /linux/drivers/spi/spi-rspi.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * SH RSPI driver
3  *
4  * Copyright (C) 2012, 2013  Renesas Solutions Corp.
5  * Copyright (C) 2014 Glider bvba
6  *
7  * Based on spi-sh.c:
8  * Copyright (C) 2011 Renesas Solutions Corp.
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; version 2 of the License.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  */
19 
20 #include <linux/module.h>
21 #include <linux/kernel.h>
22 #include <linux/sched.h>
23 #include <linux/errno.h>
24 #include <linux/interrupt.h>
25 #include <linux/platform_device.h>
26 #include <linux/io.h>
27 #include <linux/clk.h>
28 #include <linux/dmaengine.h>
29 #include <linux/dma-mapping.h>
30 #include <linux/of_device.h>
31 #include <linux/pm_runtime.h>
32 #include <linux/sh_dma.h>
33 #include <linux/spi/spi.h>
34 #include <linux/spi/rspi.h>
35 
36 #define RSPI_SPCR		0x00	/* Control Register */
37 #define RSPI_SSLP		0x01	/* Slave Select Polarity Register */
38 #define RSPI_SPPCR		0x02	/* Pin Control Register */
39 #define RSPI_SPSR		0x03	/* Status Register */
40 #define RSPI_SPDR		0x04	/* Data Register */
41 #define RSPI_SPSCR		0x08	/* Sequence Control Register */
42 #define RSPI_SPSSR		0x09	/* Sequence Status Register */
43 #define RSPI_SPBR		0x0a	/* Bit Rate Register */
44 #define RSPI_SPDCR		0x0b	/* Data Control Register */
45 #define RSPI_SPCKD		0x0c	/* Clock Delay Register */
46 #define RSPI_SSLND		0x0d	/* Slave Select Negation Delay Register */
47 #define RSPI_SPND		0x0e	/* Next-Access Delay Register */
48 #define RSPI_SPCR2		0x0f	/* Control Register 2 (SH only) */
49 #define RSPI_SPCMD0		0x10	/* Command Register 0 */
50 #define RSPI_SPCMD1		0x12	/* Command Register 1 */
51 #define RSPI_SPCMD2		0x14	/* Command Register 2 */
52 #define RSPI_SPCMD3		0x16	/* Command Register 3 */
53 #define RSPI_SPCMD4		0x18	/* Command Register 4 */
54 #define RSPI_SPCMD5		0x1a	/* Command Register 5 */
55 #define RSPI_SPCMD6		0x1c	/* Command Register 6 */
56 #define RSPI_SPCMD7		0x1e	/* Command Register 7 */
57 #define RSPI_SPCMD(i)		(RSPI_SPCMD0 + (i) * 2)
58 #define RSPI_NUM_SPCMD		8
59 #define RSPI_RZ_NUM_SPCMD	4
60 #define QSPI_NUM_SPCMD		4
61 
62 /* RSPI on RZ only */
63 #define RSPI_SPBFCR		0x20	/* Buffer Control Register */
64 #define RSPI_SPBFDR		0x22	/* Buffer Data Count Setting Register */
65 
66 /* QSPI only */
67 #define QSPI_SPBFCR		0x18	/* Buffer Control Register */
68 #define QSPI_SPBDCR		0x1a	/* Buffer Data Count Register */
69 #define QSPI_SPBMUL0		0x1c	/* Transfer Data Length Multiplier Setting Register 0 */
70 #define QSPI_SPBMUL1		0x20	/* Transfer Data Length Multiplier Setting Register 1 */
71 #define QSPI_SPBMUL2		0x24	/* Transfer Data Length Multiplier Setting Register 2 */
72 #define QSPI_SPBMUL3		0x28	/* Transfer Data Length Multiplier Setting Register 3 */
73 #define QSPI_SPBMUL(i)		(QSPI_SPBMUL0 + (i) * 4)
74 
75 /* SPCR - Control Register */
76 #define SPCR_SPRIE		0x80	/* Receive Interrupt Enable */
77 #define SPCR_SPE		0x40	/* Function Enable */
78 #define SPCR_SPTIE		0x20	/* Transmit Interrupt Enable */
79 #define SPCR_SPEIE		0x10	/* Error Interrupt Enable */
80 #define SPCR_MSTR		0x08	/* Master/Slave Mode Select */
81 #define SPCR_MODFEN		0x04	/* Mode Fault Error Detection Enable */
82 /* RSPI on SH only */
83 #define SPCR_TXMD		0x02	/* TX Only Mode (vs. Full Duplex) */
84 #define SPCR_SPMS		0x01	/* 3-wire Mode (vs. 4-wire) */
85 /* QSPI on R-Car Gen2 only */
86 #define SPCR_WSWAP		0x02	/* Word Swap of read-data for DMAC */
87 #define SPCR_BSWAP		0x01	/* Byte Swap of read-data for DMAC */
88 
89 /* SSLP - Slave Select Polarity Register */
90 #define SSLP_SSL1P		0x02	/* SSL1 Signal Polarity Setting */
91 #define SSLP_SSL0P		0x01	/* SSL0 Signal Polarity Setting */
92 
93 /* SPPCR - Pin Control Register */
94 #define SPPCR_MOIFE		0x20	/* MOSI Idle Value Fixing Enable */
95 #define SPPCR_MOIFV		0x10	/* MOSI Idle Fixed Value */
96 #define SPPCR_SPOM		0x04
97 #define SPPCR_SPLP2		0x02	/* Loopback Mode 2 (non-inverting) */
98 #define SPPCR_SPLP		0x01	/* Loopback Mode (inverting) */
99 
100 #define SPPCR_IO3FV		0x04	/* Single-/Dual-SPI Mode IO3 Output Fixed Value */
101 #define SPPCR_IO2FV		0x04	/* Single-/Dual-SPI Mode IO2 Output Fixed Value */
102 
103 /* SPSR - Status Register */
104 #define SPSR_SPRF		0x80	/* Receive Buffer Full Flag */
105 #define SPSR_TEND		0x40	/* Transmit End */
106 #define SPSR_SPTEF		0x20	/* Transmit Buffer Empty Flag */
107 #define SPSR_PERF		0x08	/* Parity Error Flag */
108 #define SPSR_MODF		0x04	/* Mode Fault Error Flag */
109 #define SPSR_IDLNF		0x02	/* RSPI Idle Flag */
110 #define SPSR_OVRF		0x01	/* Overrun Error Flag (RSPI only) */
111 
112 /* SPSCR - Sequence Control Register */
113 #define SPSCR_SPSLN_MASK	0x07	/* Sequence Length Specification */
114 
115 /* SPSSR - Sequence Status Register */
116 #define SPSSR_SPECM_MASK	0x70	/* Command Error Mask */
117 #define SPSSR_SPCP_MASK		0x07	/* Command Pointer Mask */
118 
119 /* SPDCR - Data Control Register */
120 #define SPDCR_TXDMY		0x80	/* Dummy Data Transmission Enable */
121 #define SPDCR_SPLW1		0x40	/* Access Width Specification (RZ) */
122 #define SPDCR_SPLW0		0x20	/* Access Width Specification (RZ) */
123 #define SPDCR_SPLLWORD		(SPDCR_SPLW1 | SPDCR_SPLW0)
124 #define SPDCR_SPLWORD		SPDCR_SPLW1
125 #define SPDCR_SPLBYTE		SPDCR_SPLW0
126 #define SPDCR_SPLW		0x20	/* Access Width Specification (SH) */
127 #define SPDCR_SPRDTD		0x10	/* Receive Transmit Data Select (SH) */
128 #define SPDCR_SLSEL1		0x08
129 #define SPDCR_SLSEL0		0x04
130 #define SPDCR_SLSEL_MASK	0x0c	/* SSL1 Output Select (SH) */
131 #define SPDCR_SPFC1		0x02
132 #define SPDCR_SPFC0		0x01
133 #define SPDCR_SPFC_MASK		0x03	/* Frame Count Setting (1-4) (SH) */
134 
135 /* SPCKD - Clock Delay Register */
136 #define SPCKD_SCKDL_MASK	0x07	/* Clock Delay Setting (1-8) */
137 
138 /* SSLND - Slave Select Negation Delay Register */
139 #define SSLND_SLNDL_MASK	0x07	/* SSL Negation Delay Setting (1-8) */
140 
141 /* SPND - Next-Access Delay Register */
142 #define SPND_SPNDL_MASK		0x07	/* Next-Access Delay Setting (1-8) */
143 
144 /* SPCR2 - Control Register 2 */
145 #define SPCR2_PTE		0x08	/* Parity Self-Test Enable */
146 #define SPCR2_SPIE		0x04	/* Idle Interrupt Enable */
147 #define SPCR2_SPOE		0x02	/* Odd Parity Enable (vs. Even) */
148 #define SPCR2_SPPE		0x01	/* Parity Enable */
149 
150 /* SPCMDn - Command Registers */
151 #define SPCMD_SCKDEN		0x8000	/* Clock Delay Setting Enable */
152 #define SPCMD_SLNDEN		0x4000	/* SSL Negation Delay Setting Enable */
153 #define SPCMD_SPNDEN		0x2000	/* Next-Access Delay Enable */
154 #define SPCMD_LSBF		0x1000	/* LSB First */
155 #define SPCMD_SPB_MASK		0x0f00	/* Data Length Setting */
156 #define SPCMD_SPB_8_TO_16(bit)	(((bit - 1) << 8) & SPCMD_SPB_MASK)
157 #define SPCMD_SPB_8BIT		0x0000	/* QSPI only */
158 #define SPCMD_SPB_16BIT		0x0100
159 #define SPCMD_SPB_20BIT		0x0000
160 #define SPCMD_SPB_24BIT		0x0100
161 #define SPCMD_SPB_32BIT		0x0200
162 #define SPCMD_SSLKP		0x0080	/* SSL Signal Level Keeping */
163 #define SPCMD_SPIMOD_MASK	0x0060	/* SPI Operating Mode (QSPI only) */
164 #define SPCMD_SPIMOD1		0x0040
165 #define SPCMD_SPIMOD0		0x0020
166 #define SPCMD_SPIMOD_SINGLE	0
167 #define SPCMD_SPIMOD_DUAL	SPCMD_SPIMOD0
168 #define SPCMD_SPIMOD_QUAD	SPCMD_SPIMOD1
169 #define SPCMD_SPRW		0x0010	/* SPI Read/Write Access (Dual/Quad) */
170 #define SPCMD_SSLA_MASK		0x0030	/* SSL Assert Signal Setting (RSPI) */
171 #define SPCMD_BRDV_MASK		0x000c	/* Bit Rate Division Setting */
172 #define SPCMD_CPOL		0x0002	/* Clock Polarity Setting */
173 #define SPCMD_CPHA		0x0001	/* Clock Phase Setting */
174 
175 /* SPBFCR - Buffer Control Register */
176 #define SPBFCR_TXRST		0x80	/* Transmit Buffer Data Reset */
177 #define SPBFCR_RXRST		0x40	/* Receive Buffer Data Reset */
178 #define SPBFCR_TXTRG_MASK	0x30	/* Transmit Buffer Data Triggering Number */
179 #define SPBFCR_RXTRG_MASK	0x07	/* Receive Buffer Data Triggering Number */
180 /* QSPI on R-Car Gen2 */
181 #define SPBFCR_TXTRG_1B		0x00	/* 31 bytes (1 byte available) */
182 #define SPBFCR_TXTRG_32B	0x30	/* 0 byte (32 bytes available) */
183 #define SPBFCR_RXTRG_1B		0x00	/* 1 byte (31 bytes available) */
184 #define SPBFCR_RXTRG_32B	0x07	/* 32 bytes (0 byte available) */
185 
186 #define QSPI_BUFFER_SIZE        32u
187 
188 struct rspi_data {
189 	void __iomem *addr;
190 	u32 max_speed_hz;
191 	struct spi_master *master;
192 	wait_queue_head_t wait;
193 	struct clk *clk;
194 	u16 spcmd;
195 	u8 spsr;
196 	u8 sppcr;
197 	int rx_irq, tx_irq;
198 	const struct spi_ops *ops;
199 
200 	unsigned dma_callbacked:1;
201 	unsigned byte_access:1;
202 };
203 
204 static void rspi_write8(const struct rspi_data *rspi, u8 data, u16 offset)
205 {
206 	iowrite8(data, rspi->addr + offset);
207 }
208 
209 static void rspi_write16(const struct rspi_data *rspi, u16 data, u16 offset)
210 {
211 	iowrite16(data, rspi->addr + offset);
212 }
213 
214 static void rspi_write32(const struct rspi_data *rspi, u32 data, u16 offset)
215 {
216 	iowrite32(data, rspi->addr + offset);
217 }
218 
219 static u8 rspi_read8(const struct rspi_data *rspi, u16 offset)
220 {
221 	return ioread8(rspi->addr + offset);
222 }
223 
224 static u16 rspi_read16(const struct rspi_data *rspi, u16 offset)
225 {
226 	return ioread16(rspi->addr + offset);
227 }
228 
229 static void rspi_write_data(const struct rspi_data *rspi, u16 data)
230 {
231 	if (rspi->byte_access)
232 		rspi_write8(rspi, data, RSPI_SPDR);
233 	else /* 16 bit */
234 		rspi_write16(rspi, data, RSPI_SPDR);
235 }
236 
237 static u16 rspi_read_data(const struct rspi_data *rspi)
238 {
239 	if (rspi->byte_access)
240 		return rspi_read8(rspi, RSPI_SPDR);
241 	else /* 16 bit */
242 		return rspi_read16(rspi, RSPI_SPDR);
243 }
244 
245 /* optional functions */
246 struct spi_ops {
247 	int (*set_config_register)(struct rspi_data *rspi, int access_size);
248 	int (*transfer_one)(struct spi_master *master, struct spi_device *spi,
249 			    struct spi_transfer *xfer);
250 	u16 mode_bits;
251 	u16 flags;
252 	u16 fifo_size;
253 };
254 
255 /*
256  * functions for RSPI on legacy SH
257  */
258 static int rspi_set_config_register(struct rspi_data *rspi, int access_size)
259 {
260 	int spbr;
261 
262 	/* Sets output mode, MOSI signal, and (optionally) loopback */
263 	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
264 
265 	/* Sets transfer bit rate */
266 	spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk),
267 			    2 * rspi->max_speed_hz) - 1;
268 	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
269 
270 	/* Disable dummy transmission, set 16-bit word access, 1 frame */
271 	rspi_write8(rspi, 0, RSPI_SPDCR);
272 	rspi->byte_access = 0;
273 
274 	/* Sets RSPCK, SSL, next-access delay value */
275 	rspi_write8(rspi, 0x00, RSPI_SPCKD);
276 	rspi_write8(rspi, 0x00, RSPI_SSLND);
277 	rspi_write8(rspi, 0x00, RSPI_SPND);
278 
279 	/* Sets parity, interrupt mask */
280 	rspi_write8(rspi, 0x00, RSPI_SPCR2);
281 
282 	/* Sets SPCMD */
283 	rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size);
284 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
285 
286 	/* Sets RSPI mode */
287 	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
288 
289 	return 0;
290 }
291 
292 /*
293  * functions for RSPI on RZ
294  */
295 static int rspi_rz_set_config_register(struct rspi_data *rspi, int access_size)
296 {
297 	int spbr;
298 
299 	/* Sets output mode, MOSI signal, and (optionally) loopback */
300 	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
301 
302 	/* Sets transfer bit rate */
303 	spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk),
304 			    2 * rspi->max_speed_hz) - 1;
305 	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
306 
307 	/* Disable dummy transmission, set byte access */
308 	rspi_write8(rspi, SPDCR_SPLBYTE, RSPI_SPDCR);
309 	rspi->byte_access = 1;
310 
311 	/* Sets RSPCK, SSL, next-access delay value */
312 	rspi_write8(rspi, 0x00, RSPI_SPCKD);
313 	rspi_write8(rspi, 0x00, RSPI_SSLND);
314 	rspi_write8(rspi, 0x00, RSPI_SPND);
315 
316 	/* Sets SPCMD */
317 	rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size);
318 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
319 
320 	/* Sets RSPI mode */
321 	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
322 
323 	return 0;
324 }
325 
326 /*
327  * functions for QSPI
328  */
329 static int qspi_set_config_register(struct rspi_data *rspi, int access_size)
330 {
331 	int spbr;
332 
333 	/* Sets output mode, MOSI signal, and (optionally) loopback */
334 	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
335 
336 	/* Sets transfer bit rate */
337 	spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk), 2 * rspi->max_speed_hz);
338 	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
339 
340 	/* Disable dummy transmission, set byte access */
341 	rspi_write8(rspi, 0, RSPI_SPDCR);
342 	rspi->byte_access = 1;
343 
344 	/* Sets RSPCK, SSL, next-access delay value */
345 	rspi_write8(rspi, 0x00, RSPI_SPCKD);
346 	rspi_write8(rspi, 0x00, RSPI_SSLND);
347 	rspi_write8(rspi, 0x00, RSPI_SPND);
348 
349 	/* Data Length Setting */
350 	if (access_size == 8)
351 		rspi->spcmd |= SPCMD_SPB_8BIT;
352 	else if (access_size == 16)
353 		rspi->spcmd |= SPCMD_SPB_16BIT;
354 	else
355 		rspi->spcmd |= SPCMD_SPB_32BIT;
356 
357 	rspi->spcmd |= SPCMD_SCKDEN | SPCMD_SLNDEN | SPCMD_SPNDEN;
358 
359 	/* Resets transfer data length */
360 	rspi_write32(rspi, 0, QSPI_SPBMUL0);
361 
362 	/* Resets transmit and receive buffer */
363 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
364 	/* Sets buffer to allow normal operation */
365 	rspi_write8(rspi, 0x00, QSPI_SPBFCR);
366 
367 	/* Sets SPCMD */
368 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
369 
370 	/* Enables SPI function in master mode */
371 	rspi_write8(rspi, SPCR_SPE | SPCR_MSTR, RSPI_SPCR);
372 
373 	return 0;
374 }
375 
376 static void qspi_update(const struct rspi_data *rspi, u8 mask, u8 val, u8 reg)
377 {
378 	u8 data;
379 
380 	data = rspi_read8(rspi, reg);
381 	data &= ~mask;
382 	data |= (val & mask);
383 	rspi_write8(rspi, data, reg);
384 }
385 
386 static unsigned int qspi_set_send_trigger(struct rspi_data *rspi,
387 					  unsigned int len)
388 {
389 	unsigned int n;
390 
391 	n = min(len, QSPI_BUFFER_SIZE);
392 
393 	if (len >= QSPI_BUFFER_SIZE) {
394 		/* sets triggering number to 32 bytes */
395 		qspi_update(rspi, SPBFCR_TXTRG_MASK,
396 			     SPBFCR_TXTRG_32B, QSPI_SPBFCR);
397 	} else {
398 		/* sets triggering number to 1 byte */
399 		qspi_update(rspi, SPBFCR_TXTRG_MASK,
400 			     SPBFCR_TXTRG_1B, QSPI_SPBFCR);
401 	}
402 
403 	return n;
404 }
405 
406 static void qspi_set_receive_trigger(struct rspi_data *rspi, unsigned int len)
407 {
408 	unsigned int n;
409 
410 	n = min(len, QSPI_BUFFER_SIZE);
411 
412 	if (len >= QSPI_BUFFER_SIZE) {
413 		/* sets triggering number to 32 bytes */
414 		qspi_update(rspi, SPBFCR_RXTRG_MASK,
415 			     SPBFCR_RXTRG_32B, QSPI_SPBFCR);
416 	} else {
417 		/* sets triggering number to 1 byte */
418 		qspi_update(rspi, SPBFCR_RXTRG_MASK,
419 			     SPBFCR_RXTRG_1B, QSPI_SPBFCR);
420 	}
421 }
422 
423 #define set_config_register(spi, n) spi->ops->set_config_register(spi, n)
424 
425 static void rspi_enable_irq(const struct rspi_data *rspi, u8 enable)
426 {
427 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | enable, RSPI_SPCR);
428 }
429 
430 static void rspi_disable_irq(const struct rspi_data *rspi, u8 disable)
431 {
432 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~disable, RSPI_SPCR);
433 }
434 
435 static int rspi_wait_for_interrupt(struct rspi_data *rspi, u8 wait_mask,
436 				   u8 enable_bit)
437 {
438 	int ret;
439 
440 	rspi->spsr = rspi_read8(rspi, RSPI_SPSR);
441 	if (rspi->spsr & wait_mask)
442 		return 0;
443 
444 	rspi_enable_irq(rspi, enable_bit);
445 	ret = wait_event_timeout(rspi->wait, rspi->spsr & wait_mask, HZ);
446 	if (ret == 0 && !(rspi->spsr & wait_mask))
447 		return -ETIMEDOUT;
448 
449 	return 0;
450 }
451 
452 static inline int rspi_wait_for_tx_empty(struct rspi_data *rspi)
453 {
454 	return rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
455 }
456 
457 static inline int rspi_wait_for_rx_full(struct rspi_data *rspi)
458 {
459 	return rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE);
460 }
461 
462 static int rspi_data_out(struct rspi_data *rspi, u8 data)
463 {
464 	int error = rspi_wait_for_tx_empty(rspi);
465 	if (error < 0) {
466 		dev_err(&rspi->master->dev, "transmit timeout\n");
467 		return error;
468 	}
469 	rspi_write_data(rspi, data);
470 	return 0;
471 }
472 
473 static int rspi_data_in(struct rspi_data *rspi)
474 {
475 	int error;
476 	u8 data;
477 
478 	error = rspi_wait_for_rx_full(rspi);
479 	if (error < 0) {
480 		dev_err(&rspi->master->dev, "receive timeout\n");
481 		return error;
482 	}
483 	data = rspi_read_data(rspi);
484 	return data;
485 }
486 
487 static int rspi_pio_transfer(struct rspi_data *rspi, const u8 *tx, u8 *rx,
488 			     unsigned int n)
489 {
490 	while (n-- > 0) {
491 		if (tx) {
492 			int ret = rspi_data_out(rspi, *tx++);
493 			if (ret < 0)
494 				return ret;
495 		}
496 		if (rx) {
497 			int ret = rspi_data_in(rspi);
498 			if (ret < 0)
499 				return ret;
500 			*rx++ = ret;
501 		}
502 	}
503 
504 	return 0;
505 }
506 
507 static void rspi_dma_complete(void *arg)
508 {
509 	struct rspi_data *rspi = arg;
510 
511 	rspi->dma_callbacked = 1;
512 	wake_up_interruptible(&rspi->wait);
513 }
514 
515 static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
516 			     struct sg_table *rx)
517 {
518 	struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL;
519 	u8 irq_mask = 0;
520 	unsigned int other_irq = 0;
521 	dma_cookie_t cookie;
522 	int ret;
523 
524 	/* First prepare and submit the DMA request(s), as this may fail */
525 	if (rx) {
526 		desc_rx = dmaengine_prep_slave_sg(rspi->master->dma_rx,
527 					rx->sgl, rx->nents, DMA_FROM_DEVICE,
528 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
529 		if (!desc_rx) {
530 			ret = -EAGAIN;
531 			goto no_dma_rx;
532 		}
533 
534 		desc_rx->callback = rspi_dma_complete;
535 		desc_rx->callback_param = rspi;
536 		cookie = dmaengine_submit(desc_rx);
537 		if (dma_submit_error(cookie)) {
538 			ret = cookie;
539 			goto no_dma_rx;
540 		}
541 
542 		irq_mask |= SPCR_SPRIE;
543 	}
544 
545 	if (tx) {
546 		desc_tx = dmaengine_prep_slave_sg(rspi->master->dma_tx,
547 					tx->sgl, tx->nents, DMA_TO_DEVICE,
548 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
549 		if (!desc_tx) {
550 			ret = -EAGAIN;
551 			goto no_dma_tx;
552 		}
553 
554 		if (rx) {
555 			/* No callback */
556 			desc_tx->callback = NULL;
557 		} else {
558 			desc_tx->callback = rspi_dma_complete;
559 			desc_tx->callback_param = rspi;
560 		}
561 		cookie = dmaengine_submit(desc_tx);
562 		if (dma_submit_error(cookie)) {
563 			ret = cookie;
564 			goto no_dma_tx;
565 		}
566 
567 		irq_mask |= SPCR_SPTIE;
568 	}
569 
570 	/*
571 	 * DMAC needs SPxIE, but if SPxIE is set, the IRQ routine will be
572 	 * called. So, this driver disables the IRQ while DMA transfer.
573 	 */
574 	if (tx)
575 		disable_irq(other_irq = rspi->tx_irq);
576 	if (rx && rspi->rx_irq != other_irq)
577 		disable_irq(rspi->rx_irq);
578 
579 	rspi_enable_irq(rspi, irq_mask);
580 	rspi->dma_callbacked = 0;
581 
582 	/* Now start DMA */
583 	if (rx)
584 		dma_async_issue_pending(rspi->master->dma_rx);
585 	if (tx)
586 		dma_async_issue_pending(rspi->master->dma_tx);
587 
588 	ret = wait_event_interruptible_timeout(rspi->wait,
589 					       rspi->dma_callbacked, HZ);
590 	if (ret > 0 && rspi->dma_callbacked)
591 		ret = 0;
592 	else if (!ret) {
593 		dev_err(&rspi->master->dev, "DMA timeout\n");
594 		ret = -ETIMEDOUT;
595 		if (tx)
596 			dmaengine_terminate_all(rspi->master->dma_tx);
597 		if (rx)
598 			dmaengine_terminate_all(rspi->master->dma_rx);
599 	}
600 
601 	rspi_disable_irq(rspi, irq_mask);
602 
603 	if (tx)
604 		enable_irq(rspi->tx_irq);
605 	if (rx && rspi->rx_irq != other_irq)
606 		enable_irq(rspi->rx_irq);
607 
608 	return ret;
609 
610 no_dma_tx:
611 	if (rx)
612 		dmaengine_terminate_all(rspi->master->dma_rx);
613 no_dma_rx:
614 	if (ret == -EAGAIN) {
615 		pr_warn_once("%s %s: DMA not available, falling back to PIO\n",
616 			     dev_driver_string(&rspi->master->dev),
617 			     dev_name(&rspi->master->dev));
618 	}
619 	return ret;
620 }
621 
622 static void rspi_receive_init(const struct rspi_data *rspi)
623 {
624 	u8 spsr;
625 
626 	spsr = rspi_read8(rspi, RSPI_SPSR);
627 	if (spsr & SPSR_SPRF)
628 		rspi_read_data(rspi);	/* dummy read */
629 	if (spsr & SPSR_OVRF)
630 		rspi_write8(rspi, rspi_read8(rspi, RSPI_SPSR) & ~SPSR_OVRF,
631 			    RSPI_SPSR);
632 }
633 
634 static void rspi_rz_receive_init(const struct rspi_data *rspi)
635 {
636 	rspi_receive_init(rspi);
637 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, RSPI_SPBFCR);
638 	rspi_write8(rspi, 0, RSPI_SPBFCR);
639 }
640 
641 static void qspi_receive_init(const struct rspi_data *rspi)
642 {
643 	u8 spsr;
644 
645 	spsr = rspi_read8(rspi, RSPI_SPSR);
646 	if (spsr & SPSR_SPRF)
647 		rspi_read_data(rspi);   /* dummy read */
648 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
649 	rspi_write8(rspi, 0, QSPI_SPBFCR);
650 }
651 
652 static bool __rspi_can_dma(const struct rspi_data *rspi,
653 			   const struct spi_transfer *xfer)
654 {
655 	return xfer->len > rspi->ops->fifo_size;
656 }
657 
658 static bool rspi_can_dma(struct spi_master *master, struct spi_device *spi,
659 			 struct spi_transfer *xfer)
660 {
661 	struct rspi_data *rspi = spi_master_get_devdata(master);
662 
663 	return __rspi_can_dma(rspi, xfer);
664 }
665 
666 static int rspi_dma_check_then_transfer(struct rspi_data *rspi,
667 					 struct spi_transfer *xfer)
668 {
669 	if (!rspi->master->can_dma || !__rspi_can_dma(rspi, xfer))
670 		return -EAGAIN;
671 
672 	/* rx_buf can be NULL on RSPI on SH in TX-only Mode */
673 	return rspi_dma_transfer(rspi, &xfer->tx_sg,
674 				xfer->rx_buf ? &xfer->rx_sg : NULL);
675 }
676 
677 static int rspi_common_transfer(struct rspi_data *rspi,
678 				struct spi_transfer *xfer)
679 {
680 	int ret;
681 
682 	ret = rspi_dma_check_then_transfer(rspi, xfer);
683 	if (ret != -EAGAIN)
684 		return ret;
685 
686 	ret = rspi_pio_transfer(rspi, xfer->tx_buf, xfer->rx_buf, xfer->len);
687 	if (ret < 0)
688 		return ret;
689 
690 	/* Wait for the last transmission */
691 	rspi_wait_for_tx_empty(rspi);
692 
693 	return 0;
694 }
695 
696 static int rspi_transfer_one(struct spi_master *master, struct spi_device *spi,
697 			     struct spi_transfer *xfer)
698 {
699 	struct rspi_data *rspi = spi_master_get_devdata(master);
700 	u8 spcr;
701 
702 	spcr = rspi_read8(rspi, RSPI_SPCR);
703 	if (xfer->rx_buf) {
704 		rspi_receive_init(rspi);
705 		spcr &= ~SPCR_TXMD;
706 	} else {
707 		spcr |= SPCR_TXMD;
708 	}
709 	rspi_write8(rspi, spcr, RSPI_SPCR);
710 
711 	return rspi_common_transfer(rspi, xfer);
712 }
713 
714 static int rspi_rz_transfer_one(struct spi_master *master,
715 				struct spi_device *spi,
716 				struct spi_transfer *xfer)
717 {
718 	struct rspi_data *rspi = spi_master_get_devdata(master);
719 
720 	rspi_rz_receive_init(rspi);
721 
722 	return rspi_common_transfer(rspi, xfer);
723 }
724 
725 static int qspi_trigger_transfer_out_in(struct rspi_data *rspi, const u8 *tx,
726 					u8 *rx, unsigned int len)
727 {
728 	unsigned int i, n;
729 	int ret;
730 
731 	while (len > 0) {
732 		n = qspi_set_send_trigger(rspi, len);
733 		qspi_set_receive_trigger(rspi, len);
734 		if (n == QSPI_BUFFER_SIZE) {
735 			ret = rspi_wait_for_tx_empty(rspi);
736 			if (ret < 0) {
737 				dev_err(&rspi->master->dev, "transmit timeout\n");
738 				return ret;
739 			}
740 			for (i = 0; i < n; i++)
741 				rspi_write_data(rspi, *tx++);
742 
743 			ret = rspi_wait_for_rx_full(rspi);
744 			if (ret < 0) {
745 				dev_err(&rspi->master->dev, "receive timeout\n");
746 				return ret;
747 			}
748 			for (i = 0; i < n; i++)
749 				*rx++ = rspi_read_data(rspi);
750 		} else {
751 			ret = rspi_pio_transfer(rspi, tx, rx, n);
752 			if (ret < 0)
753 				return ret;
754 		}
755 		len -= n;
756 	}
757 
758 	return 0;
759 }
760 
761 static int qspi_transfer_out_in(struct rspi_data *rspi,
762 				struct spi_transfer *xfer)
763 {
764 	int ret;
765 
766 	qspi_receive_init(rspi);
767 
768 	ret = rspi_dma_check_then_transfer(rspi, xfer);
769 	if (ret != -EAGAIN)
770 		return ret;
771 
772 	return qspi_trigger_transfer_out_in(rspi, xfer->tx_buf,
773 					    xfer->rx_buf, xfer->len);
774 }
775 
776 static int qspi_transfer_out(struct rspi_data *rspi, struct spi_transfer *xfer)
777 {
778 	int ret;
779 
780 	if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer)) {
781 		ret = rspi_dma_transfer(rspi, &xfer->tx_sg, NULL);
782 		if (ret != -EAGAIN)
783 			return ret;
784 	}
785 
786 	ret = rspi_pio_transfer(rspi, xfer->tx_buf, NULL, xfer->len);
787 	if (ret < 0)
788 		return ret;
789 
790 	/* Wait for the last transmission */
791 	rspi_wait_for_tx_empty(rspi);
792 
793 	return 0;
794 }
795 
796 static int qspi_transfer_in(struct rspi_data *rspi, struct spi_transfer *xfer)
797 {
798 	if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer)) {
799 		int ret = rspi_dma_transfer(rspi, NULL, &xfer->rx_sg);
800 		if (ret != -EAGAIN)
801 			return ret;
802 	}
803 
804 	return rspi_pio_transfer(rspi, NULL, xfer->rx_buf, xfer->len);
805 }
806 
807 static int qspi_transfer_one(struct spi_master *master, struct spi_device *spi,
808 			     struct spi_transfer *xfer)
809 {
810 	struct rspi_data *rspi = spi_master_get_devdata(master);
811 
812 	if (spi->mode & SPI_LOOP) {
813 		return qspi_transfer_out_in(rspi, xfer);
814 	} else if (xfer->tx_nbits > SPI_NBITS_SINGLE) {
815 		/* Quad or Dual SPI Write */
816 		return qspi_transfer_out(rspi, xfer);
817 	} else if (xfer->rx_nbits > SPI_NBITS_SINGLE) {
818 		/* Quad or Dual SPI Read */
819 		return qspi_transfer_in(rspi, xfer);
820 	} else {
821 		/* Single SPI Transfer */
822 		return qspi_transfer_out_in(rspi, xfer);
823 	}
824 }
825 
826 static int rspi_setup(struct spi_device *spi)
827 {
828 	struct rspi_data *rspi = spi_master_get_devdata(spi->master);
829 
830 	rspi->max_speed_hz = spi->max_speed_hz;
831 
832 	rspi->spcmd = SPCMD_SSLKP;
833 	if (spi->mode & SPI_CPOL)
834 		rspi->spcmd |= SPCMD_CPOL;
835 	if (spi->mode & SPI_CPHA)
836 		rspi->spcmd |= SPCMD_CPHA;
837 
838 	/* CMOS output mode and MOSI signal from previous transfer */
839 	rspi->sppcr = 0;
840 	if (spi->mode & SPI_LOOP)
841 		rspi->sppcr |= SPPCR_SPLP;
842 
843 	set_config_register(rspi, 8);
844 
845 	return 0;
846 }
847 
848 static u16 qspi_transfer_mode(const struct spi_transfer *xfer)
849 {
850 	if (xfer->tx_buf)
851 		switch (xfer->tx_nbits) {
852 		case SPI_NBITS_QUAD:
853 			return SPCMD_SPIMOD_QUAD;
854 		case SPI_NBITS_DUAL:
855 			return SPCMD_SPIMOD_DUAL;
856 		default:
857 			return 0;
858 		}
859 	if (xfer->rx_buf)
860 		switch (xfer->rx_nbits) {
861 		case SPI_NBITS_QUAD:
862 			return SPCMD_SPIMOD_QUAD | SPCMD_SPRW;
863 		case SPI_NBITS_DUAL:
864 			return SPCMD_SPIMOD_DUAL | SPCMD_SPRW;
865 		default:
866 			return 0;
867 		}
868 
869 	return 0;
870 }
871 
872 static int qspi_setup_sequencer(struct rspi_data *rspi,
873 				const struct spi_message *msg)
874 {
875 	const struct spi_transfer *xfer;
876 	unsigned int i = 0, len = 0;
877 	u16 current_mode = 0xffff, mode;
878 
879 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
880 		mode = qspi_transfer_mode(xfer);
881 		if (mode == current_mode) {
882 			len += xfer->len;
883 			continue;
884 		}
885 
886 		/* Transfer mode change */
887 		if (i) {
888 			/* Set transfer data length of previous transfer */
889 			rspi_write32(rspi, len, QSPI_SPBMUL(i - 1));
890 		}
891 
892 		if (i >= QSPI_NUM_SPCMD) {
893 			dev_err(&msg->spi->dev,
894 				"Too many different transfer modes");
895 			return -EINVAL;
896 		}
897 
898 		/* Program transfer mode for this transfer */
899 		rspi_write16(rspi, rspi->spcmd | mode, RSPI_SPCMD(i));
900 		current_mode = mode;
901 		len = xfer->len;
902 		i++;
903 	}
904 	if (i) {
905 		/* Set final transfer data length and sequence length */
906 		rspi_write32(rspi, len, QSPI_SPBMUL(i - 1));
907 		rspi_write8(rspi, i - 1, RSPI_SPSCR);
908 	}
909 
910 	return 0;
911 }
912 
913 static int rspi_prepare_message(struct spi_master *master,
914 				struct spi_message *msg)
915 {
916 	struct rspi_data *rspi = spi_master_get_devdata(master);
917 	int ret;
918 
919 	if (msg->spi->mode &
920 	    (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD)) {
921 		/* Setup sequencer for messages with multiple transfer modes */
922 		ret = qspi_setup_sequencer(rspi, msg);
923 		if (ret < 0)
924 			return ret;
925 	}
926 
927 	/* Enable SPI function in master mode */
928 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_SPE, RSPI_SPCR);
929 	return 0;
930 }
931 
932 static int rspi_unprepare_message(struct spi_master *master,
933 				  struct spi_message *msg)
934 {
935 	struct rspi_data *rspi = spi_master_get_devdata(master);
936 
937 	/* Disable SPI function */
938 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_SPE, RSPI_SPCR);
939 
940 	/* Reset sequencer for Single SPI Transfers */
941 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
942 	rspi_write8(rspi, 0, RSPI_SPSCR);
943 	return 0;
944 }
945 
946 static irqreturn_t rspi_irq_mux(int irq, void *_sr)
947 {
948 	struct rspi_data *rspi = _sr;
949 	u8 spsr;
950 	irqreturn_t ret = IRQ_NONE;
951 	u8 disable_irq = 0;
952 
953 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
954 	if (spsr & SPSR_SPRF)
955 		disable_irq |= SPCR_SPRIE;
956 	if (spsr & SPSR_SPTEF)
957 		disable_irq |= SPCR_SPTIE;
958 
959 	if (disable_irq) {
960 		ret = IRQ_HANDLED;
961 		rspi_disable_irq(rspi, disable_irq);
962 		wake_up(&rspi->wait);
963 	}
964 
965 	return ret;
966 }
967 
968 static irqreturn_t rspi_irq_rx(int irq, void *_sr)
969 {
970 	struct rspi_data *rspi = _sr;
971 	u8 spsr;
972 
973 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
974 	if (spsr & SPSR_SPRF) {
975 		rspi_disable_irq(rspi, SPCR_SPRIE);
976 		wake_up(&rspi->wait);
977 		return IRQ_HANDLED;
978 	}
979 
980 	return 0;
981 }
982 
983 static irqreturn_t rspi_irq_tx(int irq, void *_sr)
984 {
985 	struct rspi_data *rspi = _sr;
986 	u8 spsr;
987 
988 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
989 	if (spsr & SPSR_SPTEF) {
990 		rspi_disable_irq(rspi, SPCR_SPTIE);
991 		wake_up(&rspi->wait);
992 		return IRQ_HANDLED;
993 	}
994 
995 	return 0;
996 }
997 
998 static struct dma_chan *rspi_request_dma_chan(struct device *dev,
999 					      enum dma_transfer_direction dir,
1000 					      unsigned int id,
1001 					      dma_addr_t port_addr)
1002 {
1003 	dma_cap_mask_t mask;
1004 	struct dma_chan *chan;
1005 	struct dma_slave_config cfg;
1006 	int ret;
1007 
1008 	dma_cap_zero(mask);
1009 	dma_cap_set(DMA_SLAVE, mask);
1010 
1011 	chan = dma_request_slave_channel_compat(mask, shdma_chan_filter,
1012 				(void *)(unsigned long)id, dev,
1013 				dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1014 	if (!chan) {
1015 		dev_warn(dev, "dma_request_slave_channel_compat failed\n");
1016 		return NULL;
1017 	}
1018 
1019 	memset(&cfg, 0, sizeof(cfg));
1020 	cfg.direction = dir;
1021 	if (dir == DMA_MEM_TO_DEV) {
1022 		cfg.dst_addr = port_addr;
1023 		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1024 	} else {
1025 		cfg.src_addr = port_addr;
1026 		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1027 	}
1028 
1029 	ret = dmaengine_slave_config(chan, &cfg);
1030 	if (ret) {
1031 		dev_warn(dev, "dmaengine_slave_config failed %d\n", ret);
1032 		dma_release_channel(chan);
1033 		return NULL;
1034 	}
1035 
1036 	return chan;
1037 }
1038 
1039 static int rspi_request_dma(struct device *dev, struct spi_master *master,
1040 			    const struct resource *res)
1041 {
1042 	const struct rspi_plat_data *rspi_pd = dev_get_platdata(dev);
1043 	unsigned int dma_tx_id, dma_rx_id;
1044 
1045 	if (dev->of_node) {
1046 		/* In the OF case we will get the slave IDs from the DT */
1047 		dma_tx_id = 0;
1048 		dma_rx_id = 0;
1049 	} else if (rspi_pd && rspi_pd->dma_tx_id && rspi_pd->dma_rx_id) {
1050 		dma_tx_id = rspi_pd->dma_tx_id;
1051 		dma_rx_id = rspi_pd->dma_rx_id;
1052 	} else {
1053 		/* The driver assumes no error. */
1054 		return 0;
1055 	}
1056 
1057 	master->dma_tx = rspi_request_dma_chan(dev, DMA_MEM_TO_DEV, dma_tx_id,
1058 					       res->start + RSPI_SPDR);
1059 	if (!master->dma_tx)
1060 		return -ENODEV;
1061 
1062 	master->dma_rx = rspi_request_dma_chan(dev, DMA_DEV_TO_MEM, dma_rx_id,
1063 					       res->start + RSPI_SPDR);
1064 	if (!master->dma_rx) {
1065 		dma_release_channel(master->dma_tx);
1066 		master->dma_tx = NULL;
1067 		return -ENODEV;
1068 	}
1069 
1070 	master->can_dma = rspi_can_dma;
1071 	dev_info(dev, "DMA available");
1072 	return 0;
1073 }
1074 
1075 static void rspi_release_dma(struct spi_master *master)
1076 {
1077 	if (master->dma_tx)
1078 		dma_release_channel(master->dma_tx);
1079 	if (master->dma_rx)
1080 		dma_release_channel(master->dma_rx);
1081 }
1082 
1083 static int rspi_remove(struct platform_device *pdev)
1084 {
1085 	struct rspi_data *rspi = platform_get_drvdata(pdev);
1086 
1087 	rspi_release_dma(rspi->master);
1088 	pm_runtime_disable(&pdev->dev);
1089 
1090 	return 0;
1091 }
1092 
1093 static const struct spi_ops rspi_ops = {
1094 	.set_config_register =	rspi_set_config_register,
1095 	.transfer_one =		rspi_transfer_one,
1096 	.mode_bits =		SPI_CPHA | SPI_CPOL | SPI_LOOP,
1097 	.flags =		SPI_MASTER_MUST_TX,
1098 	.fifo_size =		8,
1099 };
1100 
1101 static const struct spi_ops rspi_rz_ops = {
1102 	.set_config_register =	rspi_rz_set_config_register,
1103 	.transfer_one =		rspi_rz_transfer_one,
1104 	.mode_bits =		SPI_CPHA | SPI_CPOL | SPI_LOOP,
1105 	.flags =		SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX,
1106 	.fifo_size =		8,	/* 8 for TX, 32 for RX */
1107 };
1108 
1109 static const struct spi_ops qspi_ops = {
1110 	.set_config_register =	qspi_set_config_register,
1111 	.transfer_one =		qspi_transfer_one,
1112 	.mode_bits =		SPI_CPHA | SPI_CPOL | SPI_LOOP |
1113 				SPI_TX_DUAL | SPI_TX_QUAD |
1114 				SPI_RX_DUAL | SPI_RX_QUAD,
1115 	.flags =		SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX,
1116 	.fifo_size =		32,
1117 };
1118 
1119 #ifdef CONFIG_OF
1120 static const struct of_device_id rspi_of_match[] = {
1121 	/* RSPI on legacy SH */
1122 	{ .compatible = "renesas,rspi", .data = &rspi_ops },
1123 	/* RSPI on RZ/A1H */
1124 	{ .compatible = "renesas,rspi-rz", .data = &rspi_rz_ops },
1125 	/* QSPI on R-Car Gen2 */
1126 	{ .compatible = "renesas,qspi", .data = &qspi_ops },
1127 	{ /* sentinel */ }
1128 };
1129 
1130 MODULE_DEVICE_TABLE(of, rspi_of_match);
1131 
1132 static int rspi_parse_dt(struct device *dev, struct spi_master *master)
1133 {
1134 	u32 num_cs;
1135 	int error;
1136 
1137 	/* Parse DT properties */
1138 	error = of_property_read_u32(dev->of_node, "num-cs", &num_cs);
1139 	if (error) {
1140 		dev_err(dev, "of_property_read_u32 num-cs failed %d\n", error);
1141 		return error;
1142 	}
1143 
1144 	master->num_chipselect = num_cs;
1145 	return 0;
1146 }
1147 #else
1148 #define rspi_of_match	NULL
1149 static inline int rspi_parse_dt(struct device *dev, struct spi_master *master)
1150 {
1151 	return -EINVAL;
1152 }
1153 #endif /* CONFIG_OF */
1154 
1155 static int rspi_request_irq(struct device *dev, unsigned int irq,
1156 			    irq_handler_t handler, const char *suffix,
1157 			    void *dev_id)
1158 {
1159 	const char *name = devm_kasprintf(dev, GFP_KERNEL, "%s:%s",
1160 					  dev_name(dev), suffix);
1161 	if (!name)
1162 		return -ENOMEM;
1163 
1164 	return devm_request_irq(dev, irq, handler, 0, name, dev_id);
1165 }
1166 
1167 static int rspi_probe(struct platform_device *pdev)
1168 {
1169 	struct resource *res;
1170 	struct spi_master *master;
1171 	struct rspi_data *rspi;
1172 	int ret;
1173 	const struct of_device_id *of_id;
1174 	const struct rspi_plat_data *rspi_pd;
1175 	const struct spi_ops *ops;
1176 
1177 	master = spi_alloc_master(&pdev->dev, sizeof(struct rspi_data));
1178 	if (master == NULL) {
1179 		dev_err(&pdev->dev, "spi_alloc_master error.\n");
1180 		return -ENOMEM;
1181 	}
1182 
1183 	of_id = of_match_device(rspi_of_match, &pdev->dev);
1184 	if (of_id) {
1185 		ops = of_id->data;
1186 		ret = rspi_parse_dt(&pdev->dev, master);
1187 		if (ret)
1188 			goto error1;
1189 	} else {
1190 		ops = (struct spi_ops *)pdev->id_entry->driver_data;
1191 		rspi_pd = dev_get_platdata(&pdev->dev);
1192 		if (rspi_pd && rspi_pd->num_chipselect)
1193 			master->num_chipselect = rspi_pd->num_chipselect;
1194 		else
1195 			master->num_chipselect = 2; /* default */
1196 	}
1197 
1198 	/* ops parameter check */
1199 	if (!ops->set_config_register) {
1200 		dev_err(&pdev->dev, "there is no set_config_register\n");
1201 		ret = -ENODEV;
1202 		goto error1;
1203 	}
1204 
1205 	rspi = spi_master_get_devdata(master);
1206 	platform_set_drvdata(pdev, rspi);
1207 	rspi->ops = ops;
1208 	rspi->master = master;
1209 
1210 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1211 	rspi->addr = devm_ioremap_resource(&pdev->dev, res);
1212 	if (IS_ERR(rspi->addr)) {
1213 		ret = PTR_ERR(rspi->addr);
1214 		goto error1;
1215 	}
1216 
1217 	rspi->clk = devm_clk_get(&pdev->dev, NULL);
1218 	if (IS_ERR(rspi->clk)) {
1219 		dev_err(&pdev->dev, "cannot get clock\n");
1220 		ret = PTR_ERR(rspi->clk);
1221 		goto error1;
1222 	}
1223 
1224 	pm_runtime_enable(&pdev->dev);
1225 
1226 	init_waitqueue_head(&rspi->wait);
1227 
1228 	master->bus_num = pdev->id;
1229 	master->setup = rspi_setup;
1230 	master->auto_runtime_pm = true;
1231 	master->transfer_one = ops->transfer_one;
1232 	master->prepare_message = rspi_prepare_message;
1233 	master->unprepare_message = rspi_unprepare_message;
1234 	master->mode_bits = ops->mode_bits;
1235 	master->flags = ops->flags;
1236 	master->dev.of_node = pdev->dev.of_node;
1237 
1238 	ret = platform_get_irq_byname(pdev, "rx");
1239 	if (ret < 0) {
1240 		ret = platform_get_irq_byname(pdev, "mux");
1241 		if (ret < 0)
1242 			ret = platform_get_irq(pdev, 0);
1243 		if (ret >= 0)
1244 			rspi->rx_irq = rspi->tx_irq = ret;
1245 	} else {
1246 		rspi->rx_irq = ret;
1247 		ret = platform_get_irq_byname(pdev, "tx");
1248 		if (ret >= 0)
1249 			rspi->tx_irq = ret;
1250 	}
1251 	if (ret < 0) {
1252 		dev_err(&pdev->dev, "platform_get_irq error\n");
1253 		goto error2;
1254 	}
1255 
1256 	if (rspi->rx_irq == rspi->tx_irq) {
1257 		/* Single multiplexed interrupt */
1258 		ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_mux,
1259 				       "mux", rspi);
1260 	} else {
1261 		/* Multi-interrupt mode, only SPRI and SPTI are used */
1262 		ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_rx,
1263 				       "rx", rspi);
1264 		if (!ret)
1265 			ret = rspi_request_irq(&pdev->dev, rspi->tx_irq,
1266 					       rspi_irq_tx, "tx", rspi);
1267 	}
1268 	if (ret < 0) {
1269 		dev_err(&pdev->dev, "request_irq error\n");
1270 		goto error2;
1271 	}
1272 
1273 	ret = rspi_request_dma(&pdev->dev, master, res);
1274 	if (ret < 0)
1275 		dev_warn(&pdev->dev, "DMA not available, using PIO\n");
1276 
1277 	ret = devm_spi_register_master(&pdev->dev, master);
1278 	if (ret < 0) {
1279 		dev_err(&pdev->dev, "spi_register_master error.\n");
1280 		goto error3;
1281 	}
1282 
1283 	dev_info(&pdev->dev, "probed\n");
1284 
1285 	return 0;
1286 
1287 error3:
1288 	rspi_release_dma(master);
1289 error2:
1290 	pm_runtime_disable(&pdev->dev);
1291 error1:
1292 	spi_master_put(master);
1293 
1294 	return ret;
1295 }
1296 
1297 static const struct platform_device_id spi_driver_ids[] = {
1298 	{ "rspi",	(kernel_ulong_t)&rspi_ops },
1299 	{ "rspi-rz",	(kernel_ulong_t)&rspi_rz_ops },
1300 	{ "qspi",	(kernel_ulong_t)&qspi_ops },
1301 	{},
1302 };
1303 
1304 MODULE_DEVICE_TABLE(platform, spi_driver_ids);
1305 
1306 static struct platform_driver rspi_driver = {
1307 	.probe =	rspi_probe,
1308 	.remove =	rspi_remove,
1309 	.id_table =	spi_driver_ids,
1310 	.driver		= {
1311 		.name = "renesas_spi",
1312 		.of_match_table = of_match_ptr(rspi_of_match),
1313 	},
1314 };
1315 module_platform_driver(rspi_driver);
1316 
1317 MODULE_DESCRIPTION("Renesas RSPI bus driver");
1318 MODULE_LICENSE("GPL v2");
1319 MODULE_AUTHOR("Yoshihiro Shimoda");
1320 MODULE_ALIAS("platform:rspi");
1321