xref: /openbmc/linux/drivers/spi/spi-rspi.c (revision 82e6fdd6)
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 	int div = 0;
299 	unsigned long clksrc;
300 
301 	/* Sets output mode, MOSI signal, and (optionally) loopback */
302 	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
303 
304 	clksrc = clk_get_rate(rspi->clk);
305 	while (div < 3) {
306 		if (rspi->max_speed_hz >= clksrc/4) /* 4=(CLK/2)/2 */
307 			break;
308 		div++;
309 		clksrc /= 2;
310 	}
311 
312 	/* Sets transfer bit rate */
313 	spbr = DIV_ROUND_UP(clksrc, 2 * rspi->max_speed_hz) - 1;
314 	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
315 	rspi->spcmd |= div << 2;
316 
317 	/* Disable dummy transmission, set byte access */
318 	rspi_write8(rspi, SPDCR_SPLBYTE, RSPI_SPDCR);
319 	rspi->byte_access = 1;
320 
321 	/* Sets RSPCK, SSL, next-access delay value */
322 	rspi_write8(rspi, 0x00, RSPI_SPCKD);
323 	rspi_write8(rspi, 0x00, RSPI_SSLND);
324 	rspi_write8(rspi, 0x00, RSPI_SPND);
325 
326 	/* Sets SPCMD */
327 	rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size);
328 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
329 
330 	/* Sets RSPI mode */
331 	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
332 
333 	return 0;
334 }
335 
336 /*
337  * functions for QSPI
338  */
339 static int qspi_set_config_register(struct rspi_data *rspi, int access_size)
340 {
341 	int spbr;
342 
343 	/* Sets output mode, MOSI signal, and (optionally) loopback */
344 	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
345 
346 	/* Sets transfer bit rate */
347 	spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk), 2 * rspi->max_speed_hz);
348 	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
349 
350 	/* Disable dummy transmission, set byte access */
351 	rspi_write8(rspi, 0, RSPI_SPDCR);
352 	rspi->byte_access = 1;
353 
354 	/* Sets RSPCK, SSL, next-access delay value */
355 	rspi_write8(rspi, 0x00, RSPI_SPCKD);
356 	rspi_write8(rspi, 0x00, RSPI_SSLND);
357 	rspi_write8(rspi, 0x00, RSPI_SPND);
358 
359 	/* Data Length Setting */
360 	if (access_size == 8)
361 		rspi->spcmd |= SPCMD_SPB_8BIT;
362 	else if (access_size == 16)
363 		rspi->spcmd |= SPCMD_SPB_16BIT;
364 	else
365 		rspi->spcmd |= SPCMD_SPB_32BIT;
366 
367 	rspi->spcmd |= SPCMD_SCKDEN | SPCMD_SLNDEN | SPCMD_SPNDEN;
368 
369 	/* Resets transfer data length */
370 	rspi_write32(rspi, 0, QSPI_SPBMUL0);
371 
372 	/* Resets transmit and receive buffer */
373 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
374 	/* Sets buffer to allow normal operation */
375 	rspi_write8(rspi, 0x00, QSPI_SPBFCR);
376 
377 	/* Sets SPCMD */
378 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
379 
380 	/* Sets RSPI mode */
381 	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
382 
383 	return 0;
384 }
385 
386 static void qspi_update(const struct rspi_data *rspi, u8 mask, u8 val, u8 reg)
387 {
388 	u8 data;
389 
390 	data = rspi_read8(rspi, reg);
391 	data &= ~mask;
392 	data |= (val & mask);
393 	rspi_write8(rspi, data, reg);
394 }
395 
396 static unsigned int qspi_set_send_trigger(struct rspi_data *rspi,
397 					  unsigned int len)
398 {
399 	unsigned int n;
400 
401 	n = min(len, QSPI_BUFFER_SIZE);
402 
403 	if (len >= QSPI_BUFFER_SIZE) {
404 		/* sets triggering number to 32 bytes */
405 		qspi_update(rspi, SPBFCR_TXTRG_MASK,
406 			     SPBFCR_TXTRG_32B, QSPI_SPBFCR);
407 	} else {
408 		/* sets triggering number to 1 byte */
409 		qspi_update(rspi, SPBFCR_TXTRG_MASK,
410 			     SPBFCR_TXTRG_1B, QSPI_SPBFCR);
411 	}
412 
413 	return n;
414 }
415 
416 static int qspi_set_receive_trigger(struct rspi_data *rspi, unsigned int len)
417 {
418 	unsigned int n;
419 
420 	n = min(len, QSPI_BUFFER_SIZE);
421 
422 	if (len >= QSPI_BUFFER_SIZE) {
423 		/* sets triggering number to 32 bytes */
424 		qspi_update(rspi, SPBFCR_RXTRG_MASK,
425 			     SPBFCR_RXTRG_32B, QSPI_SPBFCR);
426 	} else {
427 		/* sets triggering number to 1 byte */
428 		qspi_update(rspi, SPBFCR_RXTRG_MASK,
429 			     SPBFCR_RXTRG_1B, QSPI_SPBFCR);
430 	}
431 	return n;
432 }
433 
434 #define set_config_register(spi, n) spi->ops->set_config_register(spi, n)
435 
436 static void rspi_enable_irq(const struct rspi_data *rspi, u8 enable)
437 {
438 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | enable, RSPI_SPCR);
439 }
440 
441 static void rspi_disable_irq(const struct rspi_data *rspi, u8 disable)
442 {
443 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~disable, RSPI_SPCR);
444 }
445 
446 static int rspi_wait_for_interrupt(struct rspi_data *rspi, u8 wait_mask,
447 				   u8 enable_bit)
448 {
449 	int ret;
450 
451 	rspi->spsr = rspi_read8(rspi, RSPI_SPSR);
452 	if (rspi->spsr & wait_mask)
453 		return 0;
454 
455 	rspi_enable_irq(rspi, enable_bit);
456 	ret = wait_event_timeout(rspi->wait, rspi->spsr & wait_mask, HZ);
457 	if (ret == 0 && !(rspi->spsr & wait_mask))
458 		return -ETIMEDOUT;
459 
460 	return 0;
461 }
462 
463 static inline int rspi_wait_for_tx_empty(struct rspi_data *rspi)
464 {
465 	return rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
466 }
467 
468 static inline int rspi_wait_for_rx_full(struct rspi_data *rspi)
469 {
470 	return rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE);
471 }
472 
473 static int rspi_data_out(struct rspi_data *rspi, u8 data)
474 {
475 	int error = rspi_wait_for_tx_empty(rspi);
476 	if (error < 0) {
477 		dev_err(&rspi->master->dev, "transmit timeout\n");
478 		return error;
479 	}
480 	rspi_write_data(rspi, data);
481 	return 0;
482 }
483 
484 static int rspi_data_in(struct rspi_data *rspi)
485 {
486 	int error;
487 	u8 data;
488 
489 	error = rspi_wait_for_rx_full(rspi);
490 	if (error < 0) {
491 		dev_err(&rspi->master->dev, "receive timeout\n");
492 		return error;
493 	}
494 	data = rspi_read_data(rspi);
495 	return data;
496 }
497 
498 static int rspi_pio_transfer(struct rspi_data *rspi, const u8 *tx, u8 *rx,
499 			     unsigned int n)
500 {
501 	while (n-- > 0) {
502 		if (tx) {
503 			int ret = rspi_data_out(rspi, *tx++);
504 			if (ret < 0)
505 				return ret;
506 		}
507 		if (rx) {
508 			int ret = rspi_data_in(rspi);
509 			if (ret < 0)
510 				return ret;
511 			*rx++ = ret;
512 		}
513 	}
514 
515 	return 0;
516 }
517 
518 static void rspi_dma_complete(void *arg)
519 {
520 	struct rspi_data *rspi = arg;
521 
522 	rspi->dma_callbacked = 1;
523 	wake_up_interruptible(&rspi->wait);
524 }
525 
526 static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
527 			     struct sg_table *rx)
528 {
529 	struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL;
530 	u8 irq_mask = 0;
531 	unsigned int other_irq = 0;
532 	dma_cookie_t cookie;
533 	int ret;
534 
535 	/* First prepare and submit the DMA request(s), as this may fail */
536 	if (rx) {
537 		desc_rx = dmaengine_prep_slave_sg(rspi->master->dma_rx,
538 					rx->sgl, rx->nents, DMA_FROM_DEVICE,
539 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
540 		if (!desc_rx) {
541 			ret = -EAGAIN;
542 			goto no_dma_rx;
543 		}
544 
545 		desc_rx->callback = rspi_dma_complete;
546 		desc_rx->callback_param = rspi;
547 		cookie = dmaengine_submit(desc_rx);
548 		if (dma_submit_error(cookie)) {
549 			ret = cookie;
550 			goto no_dma_rx;
551 		}
552 
553 		irq_mask |= SPCR_SPRIE;
554 	}
555 
556 	if (tx) {
557 		desc_tx = dmaengine_prep_slave_sg(rspi->master->dma_tx,
558 					tx->sgl, tx->nents, DMA_TO_DEVICE,
559 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
560 		if (!desc_tx) {
561 			ret = -EAGAIN;
562 			goto no_dma_tx;
563 		}
564 
565 		if (rx) {
566 			/* No callback */
567 			desc_tx->callback = NULL;
568 		} else {
569 			desc_tx->callback = rspi_dma_complete;
570 			desc_tx->callback_param = rspi;
571 		}
572 		cookie = dmaengine_submit(desc_tx);
573 		if (dma_submit_error(cookie)) {
574 			ret = cookie;
575 			goto no_dma_tx;
576 		}
577 
578 		irq_mask |= SPCR_SPTIE;
579 	}
580 
581 	/*
582 	 * DMAC needs SPxIE, but if SPxIE is set, the IRQ routine will be
583 	 * called. So, this driver disables the IRQ while DMA transfer.
584 	 */
585 	if (tx)
586 		disable_irq(other_irq = rspi->tx_irq);
587 	if (rx && rspi->rx_irq != other_irq)
588 		disable_irq(rspi->rx_irq);
589 
590 	rspi_enable_irq(rspi, irq_mask);
591 	rspi->dma_callbacked = 0;
592 
593 	/* Now start DMA */
594 	if (rx)
595 		dma_async_issue_pending(rspi->master->dma_rx);
596 	if (tx)
597 		dma_async_issue_pending(rspi->master->dma_tx);
598 
599 	ret = wait_event_interruptible_timeout(rspi->wait,
600 					       rspi->dma_callbacked, HZ);
601 	if (ret > 0 && rspi->dma_callbacked)
602 		ret = 0;
603 	else if (!ret) {
604 		dev_err(&rspi->master->dev, "DMA timeout\n");
605 		ret = -ETIMEDOUT;
606 		if (tx)
607 			dmaengine_terminate_all(rspi->master->dma_tx);
608 		if (rx)
609 			dmaengine_terminate_all(rspi->master->dma_rx);
610 	}
611 
612 	rspi_disable_irq(rspi, irq_mask);
613 
614 	if (tx)
615 		enable_irq(rspi->tx_irq);
616 	if (rx && rspi->rx_irq != other_irq)
617 		enable_irq(rspi->rx_irq);
618 
619 	return ret;
620 
621 no_dma_tx:
622 	if (rx)
623 		dmaengine_terminate_all(rspi->master->dma_rx);
624 no_dma_rx:
625 	if (ret == -EAGAIN) {
626 		pr_warn_once("%s %s: DMA not available, falling back to PIO\n",
627 			     dev_driver_string(&rspi->master->dev),
628 			     dev_name(&rspi->master->dev));
629 	}
630 	return ret;
631 }
632 
633 static void rspi_receive_init(const struct rspi_data *rspi)
634 {
635 	u8 spsr;
636 
637 	spsr = rspi_read8(rspi, RSPI_SPSR);
638 	if (spsr & SPSR_SPRF)
639 		rspi_read_data(rspi);	/* dummy read */
640 	if (spsr & SPSR_OVRF)
641 		rspi_write8(rspi, rspi_read8(rspi, RSPI_SPSR) & ~SPSR_OVRF,
642 			    RSPI_SPSR);
643 }
644 
645 static void rspi_rz_receive_init(const struct rspi_data *rspi)
646 {
647 	rspi_receive_init(rspi);
648 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, RSPI_SPBFCR);
649 	rspi_write8(rspi, 0, RSPI_SPBFCR);
650 }
651 
652 static void qspi_receive_init(const struct rspi_data *rspi)
653 {
654 	u8 spsr;
655 
656 	spsr = rspi_read8(rspi, RSPI_SPSR);
657 	if (spsr & SPSR_SPRF)
658 		rspi_read_data(rspi);   /* dummy read */
659 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
660 	rspi_write8(rspi, 0, QSPI_SPBFCR);
661 }
662 
663 static bool __rspi_can_dma(const struct rspi_data *rspi,
664 			   const struct spi_transfer *xfer)
665 {
666 	return xfer->len > rspi->ops->fifo_size;
667 }
668 
669 static bool rspi_can_dma(struct spi_master *master, struct spi_device *spi,
670 			 struct spi_transfer *xfer)
671 {
672 	struct rspi_data *rspi = spi_master_get_devdata(master);
673 
674 	return __rspi_can_dma(rspi, xfer);
675 }
676 
677 static int rspi_dma_check_then_transfer(struct rspi_data *rspi,
678 					 struct spi_transfer *xfer)
679 {
680 	if (!rspi->master->can_dma || !__rspi_can_dma(rspi, xfer))
681 		return -EAGAIN;
682 
683 	/* rx_buf can be NULL on RSPI on SH in TX-only Mode */
684 	return rspi_dma_transfer(rspi, &xfer->tx_sg,
685 				xfer->rx_buf ? &xfer->rx_sg : NULL);
686 }
687 
688 static int rspi_common_transfer(struct rspi_data *rspi,
689 				struct spi_transfer *xfer)
690 {
691 	int ret;
692 
693 	ret = rspi_dma_check_then_transfer(rspi, xfer);
694 	if (ret != -EAGAIN)
695 		return ret;
696 
697 	ret = rspi_pio_transfer(rspi, xfer->tx_buf, xfer->rx_buf, xfer->len);
698 	if (ret < 0)
699 		return ret;
700 
701 	/* Wait for the last transmission */
702 	rspi_wait_for_tx_empty(rspi);
703 
704 	return 0;
705 }
706 
707 static int rspi_transfer_one(struct spi_master *master, struct spi_device *spi,
708 			     struct spi_transfer *xfer)
709 {
710 	struct rspi_data *rspi = spi_master_get_devdata(master);
711 	u8 spcr;
712 
713 	spcr = rspi_read8(rspi, RSPI_SPCR);
714 	if (xfer->rx_buf) {
715 		rspi_receive_init(rspi);
716 		spcr &= ~SPCR_TXMD;
717 	} else {
718 		spcr |= SPCR_TXMD;
719 	}
720 	rspi_write8(rspi, spcr, RSPI_SPCR);
721 
722 	return rspi_common_transfer(rspi, xfer);
723 }
724 
725 static int rspi_rz_transfer_one(struct spi_master *master,
726 				struct spi_device *spi,
727 				struct spi_transfer *xfer)
728 {
729 	struct rspi_data *rspi = spi_master_get_devdata(master);
730 
731 	rspi_rz_receive_init(rspi);
732 
733 	return rspi_common_transfer(rspi, xfer);
734 }
735 
736 static int qspi_trigger_transfer_out_in(struct rspi_data *rspi, const u8 *tx,
737 					u8 *rx, unsigned int len)
738 {
739 	unsigned int i, n;
740 	int ret;
741 
742 	while (len > 0) {
743 		n = qspi_set_send_trigger(rspi, len);
744 		qspi_set_receive_trigger(rspi, len);
745 		if (n == QSPI_BUFFER_SIZE) {
746 			ret = rspi_wait_for_tx_empty(rspi);
747 			if (ret < 0) {
748 				dev_err(&rspi->master->dev, "transmit timeout\n");
749 				return ret;
750 			}
751 			for (i = 0; i < n; i++)
752 				rspi_write_data(rspi, *tx++);
753 
754 			ret = rspi_wait_for_rx_full(rspi);
755 			if (ret < 0) {
756 				dev_err(&rspi->master->dev, "receive timeout\n");
757 				return ret;
758 			}
759 			for (i = 0; i < n; i++)
760 				*rx++ = rspi_read_data(rspi);
761 		} else {
762 			ret = rspi_pio_transfer(rspi, tx, rx, n);
763 			if (ret < 0)
764 				return ret;
765 		}
766 		len -= n;
767 	}
768 
769 	return 0;
770 }
771 
772 static int qspi_transfer_out_in(struct rspi_data *rspi,
773 				struct spi_transfer *xfer)
774 {
775 	int ret;
776 
777 	qspi_receive_init(rspi);
778 
779 	ret = rspi_dma_check_then_transfer(rspi, xfer);
780 	if (ret != -EAGAIN)
781 		return ret;
782 
783 	return qspi_trigger_transfer_out_in(rspi, xfer->tx_buf,
784 					    xfer->rx_buf, xfer->len);
785 }
786 
787 static int qspi_transfer_out(struct rspi_data *rspi, struct spi_transfer *xfer)
788 {
789 	const u8 *tx = xfer->tx_buf;
790 	unsigned int n = xfer->len;
791 	unsigned int i, len;
792 	int ret;
793 
794 	if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer)) {
795 		ret = rspi_dma_transfer(rspi, &xfer->tx_sg, NULL);
796 		if (ret != -EAGAIN)
797 			return ret;
798 	}
799 
800 	while (n > 0) {
801 		len = qspi_set_send_trigger(rspi, n);
802 		if (len == QSPI_BUFFER_SIZE) {
803 			ret = rspi_wait_for_tx_empty(rspi);
804 			if (ret < 0) {
805 				dev_err(&rspi->master->dev, "transmit timeout\n");
806 				return ret;
807 			}
808 			for (i = 0; i < len; i++)
809 				rspi_write_data(rspi, *tx++);
810 		} else {
811 			ret = rspi_pio_transfer(rspi, tx, NULL, len);
812 			if (ret < 0)
813 				return ret;
814 		}
815 		n -= len;
816 	}
817 
818 	/* Wait for the last transmission */
819 	rspi_wait_for_tx_empty(rspi);
820 
821 	return 0;
822 }
823 
824 static int qspi_transfer_in(struct rspi_data *rspi, struct spi_transfer *xfer)
825 {
826 	u8 *rx = xfer->rx_buf;
827 	unsigned int n = xfer->len;
828 	unsigned int i, len;
829 	int ret;
830 
831 	if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer)) {
832 		int ret = rspi_dma_transfer(rspi, NULL, &xfer->rx_sg);
833 		if (ret != -EAGAIN)
834 			return ret;
835 	}
836 
837 	while (n > 0) {
838 		len = qspi_set_receive_trigger(rspi, n);
839 		if (len == QSPI_BUFFER_SIZE) {
840 			ret = rspi_wait_for_rx_full(rspi);
841 			if (ret < 0) {
842 				dev_err(&rspi->master->dev, "receive timeout\n");
843 				return ret;
844 			}
845 			for (i = 0; i < len; i++)
846 				*rx++ = rspi_read_data(rspi);
847 		} else {
848 			ret = rspi_pio_transfer(rspi, NULL, rx, len);
849 			if (ret < 0)
850 				return ret;
851 		}
852 		n -= len;
853 	}
854 
855 	return 0;
856 }
857 
858 static int qspi_transfer_one(struct spi_master *master, struct spi_device *spi,
859 			     struct spi_transfer *xfer)
860 {
861 	struct rspi_data *rspi = spi_master_get_devdata(master);
862 
863 	if (spi->mode & SPI_LOOP) {
864 		return qspi_transfer_out_in(rspi, xfer);
865 	} else if (xfer->tx_nbits > SPI_NBITS_SINGLE) {
866 		/* Quad or Dual SPI Write */
867 		return qspi_transfer_out(rspi, xfer);
868 	} else if (xfer->rx_nbits > SPI_NBITS_SINGLE) {
869 		/* Quad or Dual SPI Read */
870 		return qspi_transfer_in(rspi, xfer);
871 	} else {
872 		/* Single SPI Transfer */
873 		return qspi_transfer_out_in(rspi, xfer);
874 	}
875 }
876 
877 static int rspi_setup(struct spi_device *spi)
878 {
879 	struct rspi_data *rspi = spi_master_get_devdata(spi->master);
880 
881 	rspi->max_speed_hz = spi->max_speed_hz;
882 
883 	rspi->spcmd = SPCMD_SSLKP;
884 	if (spi->mode & SPI_CPOL)
885 		rspi->spcmd |= SPCMD_CPOL;
886 	if (spi->mode & SPI_CPHA)
887 		rspi->spcmd |= SPCMD_CPHA;
888 
889 	/* CMOS output mode and MOSI signal from previous transfer */
890 	rspi->sppcr = 0;
891 	if (spi->mode & SPI_LOOP)
892 		rspi->sppcr |= SPPCR_SPLP;
893 
894 	set_config_register(rspi, 8);
895 
896 	return 0;
897 }
898 
899 static u16 qspi_transfer_mode(const struct spi_transfer *xfer)
900 {
901 	if (xfer->tx_buf)
902 		switch (xfer->tx_nbits) {
903 		case SPI_NBITS_QUAD:
904 			return SPCMD_SPIMOD_QUAD;
905 		case SPI_NBITS_DUAL:
906 			return SPCMD_SPIMOD_DUAL;
907 		default:
908 			return 0;
909 		}
910 	if (xfer->rx_buf)
911 		switch (xfer->rx_nbits) {
912 		case SPI_NBITS_QUAD:
913 			return SPCMD_SPIMOD_QUAD | SPCMD_SPRW;
914 		case SPI_NBITS_DUAL:
915 			return SPCMD_SPIMOD_DUAL | SPCMD_SPRW;
916 		default:
917 			return 0;
918 		}
919 
920 	return 0;
921 }
922 
923 static int qspi_setup_sequencer(struct rspi_data *rspi,
924 				const struct spi_message *msg)
925 {
926 	const struct spi_transfer *xfer;
927 	unsigned int i = 0, len = 0;
928 	u16 current_mode = 0xffff, mode;
929 
930 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
931 		mode = qspi_transfer_mode(xfer);
932 		if (mode == current_mode) {
933 			len += xfer->len;
934 			continue;
935 		}
936 
937 		/* Transfer mode change */
938 		if (i) {
939 			/* Set transfer data length of previous transfer */
940 			rspi_write32(rspi, len, QSPI_SPBMUL(i - 1));
941 		}
942 
943 		if (i >= QSPI_NUM_SPCMD) {
944 			dev_err(&msg->spi->dev,
945 				"Too many different transfer modes");
946 			return -EINVAL;
947 		}
948 
949 		/* Program transfer mode for this transfer */
950 		rspi_write16(rspi, rspi->spcmd | mode, RSPI_SPCMD(i));
951 		current_mode = mode;
952 		len = xfer->len;
953 		i++;
954 	}
955 	if (i) {
956 		/* Set final transfer data length and sequence length */
957 		rspi_write32(rspi, len, QSPI_SPBMUL(i - 1));
958 		rspi_write8(rspi, i - 1, RSPI_SPSCR);
959 	}
960 
961 	return 0;
962 }
963 
964 static int rspi_prepare_message(struct spi_master *master,
965 				struct spi_message *msg)
966 {
967 	struct rspi_data *rspi = spi_master_get_devdata(master);
968 	int ret;
969 
970 	if (msg->spi->mode &
971 	    (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD)) {
972 		/* Setup sequencer for messages with multiple transfer modes */
973 		ret = qspi_setup_sequencer(rspi, msg);
974 		if (ret < 0)
975 			return ret;
976 	}
977 
978 	/* Enable SPI function in master mode */
979 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_SPE, RSPI_SPCR);
980 	return 0;
981 }
982 
983 static int rspi_unprepare_message(struct spi_master *master,
984 				  struct spi_message *msg)
985 {
986 	struct rspi_data *rspi = spi_master_get_devdata(master);
987 
988 	/* Disable SPI function */
989 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_SPE, RSPI_SPCR);
990 
991 	/* Reset sequencer for Single SPI Transfers */
992 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
993 	rspi_write8(rspi, 0, RSPI_SPSCR);
994 	return 0;
995 }
996 
997 static irqreturn_t rspi_irq_mux(int irq, void *_sr)
998 {
999 	struct rspi_data *rspi = _sr;
1000 	u8 spsr;
1001 	irqreturn_t ret = IRQ_NONE;
1002 	u8 disable_irq = 0;
1003 
1004 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
1005 	if (spsr & SPSR_SPRF)
1006 		disable_irq |= SPCR_SPRIE;
1007 	if (spsr & SPSR_SPTEF)
1008 		disable_irq |= SPCR_SPTIE;
1009 
1010 	if (disable_irq) {
1011 		ret = IRQ_HANDLED;
1012 		rspi_disable_irq(rspi, disable_irq);
1013 		wake_up(&rspi->wait);
1014 	}
1015 
1016 	return ret;
1017 }
1018 
1019 static irqreturn_t rspi_irq_rx(int irq, void *_sr)
1020 {
1021 	struct rspi_data *rspi = _sr;
1022 	u8 spsr;
1023 
1024 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
1025 	if (spsr & SPSR_SPRF) {
1026 		rspi_disable_irq(rspi, SPCR_SPRIE);
1027 		wake_up(&rspi->wait);
1028 		return IRQ_HANDLED;
1029 	}
1030 
1031 	return 0;
1032 }
1033 
1034 static irqreturn_t rspi_irq_tx(int irq, void *_sr)
1035 {
1036 	struct rspi_data *rspi = _sr;
1037 	u8 spsr;
1038 
1039 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
1040 	if (spsr & SPSR_SPTEF) {
1041 		rspi_disable_irq(rspi, SPCR_SPTIE);
1042 		wake_up(&rspi->wait);
1043 		return IRQ_HANDLED;
1044 	}
1045 
1046 	return 0;
1047 }
1048 
1049 static struct dma_chan *rspi_request_dma_chan(struct device *dev,
1050 					      enum dma_transfer_direction dir,
1051 					      unsigned int id,
1052 					      dma_addr_t port_addr)
1053 {
1054 	dma_cap_mask_t mask;
1055 	struct dma_chan *chan;
1056 	struct dma_slave_config cfg;
1057 	int ret;
1058 
1059 	dma_cap_zero(mask);
1060 	dma_cap_set(DMA_SLAVE, mask);
1061 
1062 	chan = dma_request_slave_channel_compat(mask, shdma_chan_filter,
1063 				(void *)(unsigned long)id, dev,
1064 				dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1065 	if (!chan) {
1066 		dev_warn(dev, "dma_request_slave_channel_compat failed\n");
1067 		return NULL;
1068 	}
1069 
1070 	memset(&cfg, 0, sizeof(cfg));
1071 	cfg.direction = dir;
1072 	if (dir == DMA_MEM_TO_DEV) {
1073 		cfg.dst_addr = port_addr;
1074 		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1075 	} else {
1076 		cfg.src_addr = port_addr;
1077 		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1078 	}
1079 
1080 	ret = dmaengine_slave_config(chan, &cfg);
1081 	if (ret) {
1082 		dev_warn(dev, "dmaengine_slave_config failed %d\n", ret);
1083 		dma_release_channel(chan);
1084 		return NULL;
1085 	}
1086 
1087 	return chan;
1088 }
1089 
1090 static int rspi_request_dma(struct device *dev, struct spi_master *master,
1091 			    const struct resource *res)
1092 {
1093 	const struct rspi_plat_data *rspi_pd = dev_get_platdata(dev);
1094 	unsigned int dma_tx_id, dma_rx_id;
1095 
1096 	if (dev->of_node) {
1097 		/* In the OF case we will get the slave IDs from the DT */
1098 		dma_tx_id = 0;
1099 		dma_rx_id = 0;
1100 	} else if (rspi_pd && rspi_pd->dma_tx_id && rspi_pd->dma_rx_id) {
1101 		dma_tx_id = rspi_pd->dma_tx_id;
1102 		dma_rx_id = rspi_pd->dma_rx_id;
1103 	} else {
1104 		/* The driver assumes no error. */
1105 		return 0;
1106 	}
1107 
1108 	master->dma_tx = rspi_request_dma_chan(dev, DMA_MEM_TO_DEV, dma_tx_id,
1109 					       res->start + RSPI_SPDR);
1110 	if (!master->dma_tx)
1111 		return -ENODEV;
1112 
1113 	master->dma_rx = rspi_request_dma_chan(dev, DMA_DEV_TO_MEM, dma_rx_id,
1114 					       res->start + RSPI_SPDR);
1115 	if (!master->dma_rx) {
1116 		dma_release_channel(master->dma_tx);
1117 		master->dma_tx = NULL;
1118 		return -ENODEV;
1119 	}
1120 
1121 	master->can_dma = rspi_can_dma;
1122 	dev_info(dev, "DMA available");
1123 	return 0;
1124 }
1125 
1126 static void rspi_release_dma(struct spi_master *master)
1127 {
1128 	if (master->dma_tx)
1129 		dma_release_channel(master->dma_tx);
1130 	if (master->dma_rx)
1131 		dma_release_channel(master->dma_rx);
1132 }
1133 
1134 static int rspi_remove(struct platform_device *pdev)
1135 {
1136 	struct rspi_data *rspi = platform_get_drvdata(pdev);
1137 
1138 	rspi_release_dma(rspi->master);
1139 	pm_runtime_disable(&pdev->dev);
1140 
1141 	return 0;
1142 }
1143 
1144 static const struct spi_ops rspi_ops = {
1145 	.set_config_register =	rspi_set_config_register,
1146 	.transfer_one =		rspi_transfer_one,
1147 	.mode_bits =		SPI_CPHA | SPI_CPOL | SPI_LOOP,
1148 	.flags =		SPI_MASTER_MUST_TX,
1149 	.fifo_size =		8,
1150 };
1151 
1152 static const struct spi_ops rspi_rz_ops = {
1153 	.set_config_register =	rspi_rz_set_config_register,
1154 	.transfer_one =		rspi_rz_transfer_one,
1155 	.mode_bits =		SPI_CPHA | SPI_CPOL | SPI_LOOP,
1156 	.flags =		SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX,
1157 	.fifo_size =		8,	/* 8 for TX, 32 for RX */
1158 };
1159 
1160 static const struct spi_ops qspi_ops = {
1161 	.set_config_register =	qspi_set_config_register,
1162 	.transfer_one =		qspi_transfer_one,
1163 	.mode_bits =		SPI_CPHA | SPI_CPOL | SPI_LOOP |
1164 				SPI_TX_DUAL | SPI_TX_QUAD |
1165 				SPI_RX_DUAL | SPI_RX_QUAD,
1166 	.flags =		SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX,
1167 	.fifo_size =		32,
1168 };
1169 
1170 #ifdef CONFIG_OF
1171 static const struct of_device_id rspi_of_match[] = {
1172 	/* RSPI on legacy SH */
1173 	{ .compatible = "renesas,rspi", .data = &rspi_ops },
1174 	/* RSPI on RZ/A1H */
1175 	{ .compatible = "renesas,rspi-rz", .data = &rspi_rz_ops },
1176 	/* QSPI on R-Car Gen2 */
1177 	{ .compatible = "renesas,qspi", .data = &qspi_ops },
1178 	{ /* sentinel */ }
1179 };
1180 
1181 MODULE_DEVICE_TABLE(of, rspi_of_match);
1182 
1183 static int rspi_parse_dt(struct device *dev, struct spi_master *master)
1184 {
1185 	u32 num_cs;
1186 	int error;
1187 
1188 	/* Parse DT properties */
1189 	error = of_property_read_u32(dev->of_node, "num-cs", &num_cs);
1190 	if (error) {
1191 		dev_err(dev, "of_property_read_u32 num-cs failed %d\n", error);
1192 		return error;
1193 	}
1194 
1195 	master->num_chipselect = num_cs;
1196 	return 0;
1197 }
1198 #else
1199 #define rspi_of_match	NULL
1200 static inline int rspi_parse_dt(struct device *dev, struct spi_master *master)
1201 {
1202 	return -EINVAL;
1203 }
1204 #endif /* CONFIG_OF */
1205 
1206 static int rspi_request_irq(struct device *dev, unsigned int irq,
1207 			    irq_handler_t handler, const char *suffix,
1208 			    void *dev_id)
1209 {
1210 	const char *name = devm_kasprintf(dev, GFP_KERNEL, "%s:%s",
1211 					  dev_name(dev), suffix);
1212 	if (!name)
1213 		return -ENOMEM;
1214 
1215 	return devm_request_irq(dev, irq, handler, 0, name, dev_id);
1216 }
1217 
1218 static int rspi_probe(struct platform_device *pdev)
1219 {
1220 	struct resource *res;
1221 	struct spi_master *master;
1222 	struct rspi_data *rspi;
1223 	int ret;
1224 	const struct rspi_plat_data *rspi_pd;
1225 	const struct spi_ops *ops;
1226 
1227 	master = spi_alloc_master(&pdev->dev, sizeof(struct rspi_data));
1228 	if (master == NULL)
1229 		return -ENOMEM;
1230 
1231 	ops = of_device_get_match_data(&pdev->dev);
1232 	if (ops) {
1233 		ret = rspi_parse_dt(&pdev->dev, master);
1234 		if (ret)
1235 			goto error1;
1236 	} else {
1237 		ops = (struct spi_ops *)pdev->id_entry->driver_data;
1238 		rspi_pd = dev_get_platdata(&pdev->dev);
1239 		if (rspi_pd && rspi_pd->num_chipselect)
1240 			master->num_chipselect = rspi_pd->num_chipselect;
1241 		else
1242 			master->num_chipselect = 2; /* default */
1243 	}
1244 
1245 	/* ops parameter check */
1246 	if (!ops->set_config_register) {
1247 		dev_err(&pdev->dev, "there is no set_config_register\n");
1248 		ret = -ENODEV;
1249 		goto error1;
1250 	}
1251 
1252 	rspi = spi_master_get_devdata(master);
1253 	platform_set_drvdata(pdev, rspi);
1254 	rspi->ops = ops;
1255 	rspi->master = master;
1256 
1257 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1258 	rspi->addr = devm_ioremap_resource(&pdev->dev, res);
1259 	if (IS_ERR(rspi->addr)) {
1260 		ret = PTR_ERR(rspi->addr);
1261 		goto error1;
1262 	}
1263 
1264 	rspi->clk = devm_clk_get(&pdev->dev, NULL);
1265 	if (IS_ERR(rspi->clk)) {
1266 		dev_err(&pdev->dev, "cannot get clock\n");
1267 		ret = PTR_ERR(rspi->clk);
1268 		goto error1;
1269 	}
1270 
1271 	pm_runtime_enable(&pdev->dev);
1272 
1273 	init_waitqueue_head(&rspi->wait);
1274 
1275 	master->bus_num = pdev->id;
1276 	master->setup = rspi_setup;
1277 	master->auto_runtime_pm = true;
1278 	master->transfer_one = ops->transfer_one;
1279 	master->prepare_message = rspi_prepare_message;
1280 	master->unprepare_message = rspi_unprepare_message;
1281 	master->mode_bits = ops->mode_bits;
1282 	master->flags = ops->flags;
1283 	master->dev.of_node = pdev->dev.of_node;
1284 
1285 	ret = platform_get_irq_byname(pdev, "rx");
1286 	if (ret < 0) {
1287 		ret = platform_get_irq_byname(pdev, "mux");
1288 		if (ret < 0)
1289 			ret = platform_get_irq(pdev, 0);
1290 		if (ret >= 0)
1291 			rspi->rx_irq = rspi->tx_irq = ret;
1292 	} else {
1293 		rspi->rx_irq = ret;
1294 		ret = platform_get_irq_byname(pdev, "tx");
1295 		if (ret >= 0)
1296 			rspi->tx_irq = ret;
1297 	}
1298 	if (ret < 0) {
1299 		dev_err(&pdev->dev, "platform_get_irq error\n");
1300 		goto error2;
1301 	}
1302 
1303 	if (rspi->rx_irq == rspi->tx_irq) {
1304 		/* Single multiplexed interrupt */
1305 		ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_mux,
1306 				       "mux", rspi);
1307 	} else {
1308 		/* Multi-interrupt mode, only SPRI and SPTI are used */
1309 		ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_rx,
1310 				       "rx", rspi);
1311 		if (!ret)
1312 			ret = rspi_request_irq(&pdev->dev, rspi->tx_irq,
1313 					       rspi_irq_tx, "tx", rspi);
1314 	}
1315 	if (ret < 0) {
1316 		dev_err(&pdev->dev, "request_irq error\n");
1317 		goto error2;
1318 	}
1319 
1320 	ret = rspi_request_dma(&pdev->dev, master, res);
1321 	if (ret < 0)
1322 		dev_warn(&pdev->dev, "DMA not available, using PIO\n");
1323 
1324 	ret = devm_spi_register_master(&pdev->dev, master);
1325 	if (ret < 0) {
1326 		dev_err(&pdev->dev, "spi_register_master error.\n");
1327 		goto error3;
1328 	}
1329 
1330 	dev_info(&pdev->dev, "probed\n");
1331 
1332 	return 0;
1333 
1334 error3:
1335 	rspi_release_dma(master);
1336 error2:
1337 	pm_runtime_disable(&pdev->dev);
1338 error1:
1339 	spi_master_put(master);
1340 
1341 	return ret;
1342 }
1343 
1344 static const struct platform_device_id spi_driver_ids[] = {
1345 	{ "rspi",	(kernel_ulong_t)&rspi_ops },
1346 	{ "rspi-rz",	(kernel_ulong_t)&rspi_rz_ops },
1347 	{ "qspi",	(kernel_ulong_t)&qspi_ops },
1348 	{},
1349 };
1350 
1351 MODULE_DEVICE_TABLE(platform, spi_driver_ids);
1352 
1353 static struct platform_driver rspi_driver = {
1354 	.probe =	rspi_probe,
1355 	.remove =	rspi_remove,
1356 	.id_table =	spi_driver_ids,
1357 	.driver		= {
1358 		.name = "renesas_spi",
1359 		.of_match_table = of_match_ptr(rspi_of_match),
1360 	},
1361 };
1362 module_platform_driver(rspi_driver);
1363 
1364 MODULE_DESCRIPTION("Renesas RSPI bus driver");
1365 MODULE_LICENSE("GPL v2");
1366 MODULE_AUTHOR("Yoshihiro Shimoda");
1367 MODULE_ALIAS("platform:rspi");
1368