xref: /openbmc/linux/drivers/spi/spi-rspi.c (revision 6f69e2a3)
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_controller *ctlr;
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_controller *ctlr,
241 			    struct spi_device *spi, 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 	/* Resets sequencer */
275 	rspi_write8(rspi, 0, RSPI_SPSCR);
276 	rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size);
277 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
278 
279 	/* Sets RSPI mode */
280 	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
281 
282 	return 0;
283 }
284 
285 /*
286  * functions for RSPI on RZ
287  */
288 static int rspi_rz_set_config_register(struct rspi_data *rspi, int access_size)
289 {
290 	int spbr;
291 	int div = 0;
292 	unsigned long clksrc;
293 
294 	/* Sets output mode, MOSI signal, and (optionally) loopback */
295 	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
296 
297 	clksrc = clk_get_rate(rspi->clk);
298 	while (div < 3) {
299 		if (rspi->max_speed_hz >= clksrc/4) /* 4=(CLK/2)/2 */
300 			break;
301 		div++;
302 		clksrc /= 2;
303 	}
304 
305 	/* Sets transfer bit rate */
306 	spbr = DIV_ROUND_UP(clksrc, 2 * rspi->max_speed_hz) - 1;
307 	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
308 	rspi->spcmd |= div << 2;
309 
310 	/* Disable dummy transmission, set byte access */
311 	rspi_write8(rspi, SPDCR_SPLBYTE, RSPI_SPDCR);
312 	rspi->byte_access = 1;
313 
314 	/* Sets RSPCK, SSL, next-access delay value */
315 	rspi_write8(rspi, 0x00, RSPI_SPCKD);
316 	rspi_write8(rspi, 0x00, RSPI_SSLND);
317 	rspi_write8(rspi, 0x00, RSPI_SPND);
318 
319 	/* Resets sequencer */
320 	rspi_write8(rspi, 0, RSPI_SPSCR);
321 	rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size);
322 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
323 
324 	/* Sets RSPI mode */
325 	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
326 
327 	return 0;
328 }
329 
330 /*
331  * functions for QSPI
332  */
333 static int qspi_set_config_register(struct rspi_data *rspi, int access_size)
334 {
335 	int spbr;
336 
337 	/* Sets output mode, MOSI signal, and (optionally) loopback */
338 	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
339 
340 	/* Sets transfer bit rate */
341 	spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk), 2 * rspi->max_speed_hz);
342 	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
343 
344 	/* Disable dummy transmission, set byte access */
345 	rspi_write8(rspi, 0, RSPI_SPDCR);
346 	rspi->byte_access = 1;
347 
348 	/* Sets RSPCK, SSL, next-access delay value */
349 	rspi_write8(rspi, 0x00, RSPI_SPCKD);
350 	rspi_write8(rspi, 0x00, RSPI_SSLND);
351 	rspi_write8(rspi, 0x00, RSPI_SPND);
352 
353 	/* Data Length Setting */
354 	if (access_size == 8)
355 		rspi->spcmd |= SPCMD_SPB_8BIT;
356 	else if (access_size == 16)
357 		rspi->spcmd |= SPCMD_SPB_16BIT;
358 	else
359 		rspi->spcmd |= SPCMD_SPB_32BIT;
360 
361 	rspi->spcmd |= SPCMD_SCKDEN | SPCMD_SLNDEN | SPCMD_SPNDEN;
362 
363 	/* Resets transfer data length */
364 	rspi_write32(rspi, 0, QSPI_SPBMUL0);
365 
366 	/* Resets transmit and receive buffer */
367 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
368 	/* Sets buffer to allow normal operation */
369 	rspi_write8(rspi, 0x00, QSPI_SPBFCR);
370 
371 	/* Resets sequencer */
372 	rspi_write8(rspi, 0, RSPI_SPSCR);
373 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
374 
375 	/* Sets RSPI mode */
376 	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
377 
378 	return 0;
379 }
380 
381 static void qspi_update(const struct rspi_data *rspi, u8 mask, u8 val, u8 reg)
382 {
383 	u8 data;
384 
385 	data = rspi_read8(rspi, reg);
386 	data &= ~mask;
387 	data |= (val & mask);
388 	rspi_write8(rspi, data, reg);
389 }
390 
391 static unsigned int qspi_set_send_trigger(struct rspi_data *rspi,
392 					  unsigned int len)
393 {
394 	unsigned int n;
395 
396 	n = min(len, QSPI_BUFFER_SIZE);
397 
398 	if (len >= QSPI_BUFFER_SIZE) {
399 		/* sets triggering number to 32 bytes */
400 		qspi_update(rspi, SPBFCR_TXTRG_MASK,
401 			     SPBFCR_TXTRG_32B, QSPI_SPBFCR);
402 	} else {
403 		/* sets triggering number to 1 byte */
404 		qspi_update(rspi, SPBFCR_TXTRG_MASK,
405 			     SPBFCR_TXTRG_1B, QSPI_SPBFCR);
406 	}
407 
408 	return n;
409 }
410 
411 static int qspi_set_receive_trigger(struct rspi_data *rspi, unsigned int len)
412 {
413 	unsigned int n;
414 
415 	n = min(len, QSPI_BUFFER_SIZE);
416 
417 	if (len >= QSPI_BUFFER_SIZE) {
418 		/* sets triggering number to 32 bytes */
419 		qspi_update(rspi, SPBFCR_RXTRG_MASK,
420 			     SPBFCR_RXTRG_32B, QSPI_SPBFCR);
421 	} else {
422 		/* sets triggering number to 1 byte */
423 		qspi_update(rspi, SPBFCR_RXTRG_MASK,
424 			     SPBFCR_RXTRG_1B, QSPI_SPBFCR);
425 	}
426 	return n;
427 }
428 
429 #define set_config_register(spi, n) spi->ops->set_config_register(spi, n)
430 
431 static void rspi_enable_irq(const struct rspi_data *rspi, u8 enable)
432 {
433 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | enable, RSPI_SPCR);
434 }
435 
436 static void rspi_disable_irq(const struct rspi_data *rspi, u8 disable)
437 {
438 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~disable, RSPI_SPCR);
439 }
440 
441 static int rspi_wait_for_interrupt(struct rspi_data *rspi, u8 wait_mask,
442 				   u8 enable_bit)
443 {
444 	int ret;
445 
446 	rspi->spsr = rspi_read8(rspi, RSPI_SPSR);
447 	if (rspi->spsr & wait_mask)
448 		return 0;
449 
450 	rspi_enable_irq(rspi, enable_bit);
451 	ret = wait_event_timeout(rspi->wait, rspi->spsr & wait_mask, HZ);
452 	if (ret == 0 && !(rspi->spsr & wait_mask))
453 		return -ETIMEDOUT;
454 
455 	return 0;
456 }
457 
458 static inline int rspi_wait_for_tx_empty(struct rspi_data *rspi)
459 {
460 	return rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
461 }
462 
463 static inline int rspi_wait_for_rx_full(struct rspi_data *rspi)
464 {
465 	return rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE);
466 }
467 
468 static int rspi_data_out(struct rspi_data *rspi, u8 data)
469 {
470 	int error = rspi_wait_for_tx_empty(rspi);
471 	if (error < 0) {
472 		dev_err(&rspi->ctlr->dev, "transmit timeout\n");
473 		return error;
474 	}
475 	rspi_write_data(rspi, data);
476 	return 0;
477 }
478 
479 static int rspi_data_in(struct rspi_data *rspi)
480 {
481 	int error;
482 	u8 data;
483 
484 	error = rspi_wait_for_rx_full(rspi);
485 	if (error < 0) {
486 		dev_err(&rspi->ctlr->dev, "receive timeout\n");
487 		return error;
488 	}
489 	data = rspi_read_data(rspi);
490 	return data;
491 }
492 
493 static int rspi_pio_transfer(struct rspi_data *rspi, const u8 *tx, u8 *rx,
494 			     unsigned int n)
495 {
496 	while (n-- > 0) {
497 		if (tx) {
498 			int ret = rspi_data_out(rspi, *tx++);
499 			if (ret < 0)
500 				return ret;
501 		}
502 		if (rx) {
503 			int ret = rspi_data_in(rspi);
504 			if (ret < 0)
505 				return ret;
506 			*rx++ = ret;
507 		}
508 	}
509 
510 	return 0;
511 }
512 
513 static void rspi_dma_complete(void *arg)
514 {
515 	struct rspi_data *rspi = arg;
516 
517 	rspi->dma_callbacked = 1;
518 	wake_up_interruptible(&rspi->wait);
519 }
520 
521 static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
522 			     struct sg_table *rx)
523 {
524 	struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL;
525 	u8 irq_mask = 0;
526 	unsigned int other_irq = 0;
527 	dma_cookie_t cookie;
528 	int ret;
529 
530 	/* First prepare and submit the DMA request(s), as this may fail */
531 	if (rx) {
532 		desc_rx = dmaengine_prep_slave_sg(rspi->ctlr->dma_rx, rx->sgl,
533 					rx->nents, DMA_DEV_TO_MEM,
534 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
535 		if (!desc_rx) {
536 			ret = -EAGAIN;
537 			goto no_dma_rx;
538 		}
539 
540 		desc_rx->callback = rspi_dma_complete;
541 		desc_rx->callback_param = rspi;
542 		cookie = dmaengine_submit(desc_rx);
543 		if (dma_submit_error(cookie)) {
544 			ret = cookie;
545 			goto no_dma_rx;
546 		}
547 
548 		irq_mask |= SPCR_SPRIE;
549 	}
550 
551 	if (tx) {
552 		desc_tx = dmaengine_prep_slave_sg(rspi->ctlr->dma_tx, tx->sgl,
553 					tx->nents, DMA_MEM_TO_DEV,
554 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
555 		if (!desc_tx) {
556 			ret = -EAGAIN;
557 			goto no_dma_tx;
558 		}
559 
560 		if (rx) {
561 			/* No callback */
562 			desc_tx->callback = NULL;
563 		} else {
564 			desc_tx->callback = rspi_dma_complete;
565 			desc_tx->callback_param = rspi;
566 		}
567 		cookie = dmaengine_submit(desc_tx);
568 		if (dma_submit_error(cookie)) {
569 			ret = cookie;
570 			goto no_dma_tx;
571 		}
572 
573 		irq_mask |= SPCR_SPTIE;
574 	}
575 
576 	/*
577 	 * DMAC needs SPxIE, but if SPxIE is set, the IRQ routine will be
578 	 * called. So, this driver disables the IRQ while DMA transfer.
579 	 */
580 	if (tx)
581 		disable_irq(other_irq = rspi->tx_irq);
582 	if (rx && rspi->rx_irq != other_irq)
583 		disable_irq(rspi->rx_irq);
584 
585 	rspi_enable_irq(rspi, irq_mask);
586 	rspi->dma_callbacked = 0;
587 
588 	/* Now start DMA */
589 	if (rx)
590 		dma_async_issue_pending(rspi->ctlr->dma_rx);
591 	if (tx)
592 		dma_async_issue_pending(rspi->ctlr->dma_tx);
593 
594 	ret = wait_event_interruptible_timeout(rspi->wait,
595 					       rspi->dma_callbacked, HZ);
596 	if (ret > 0 && rspi->dma_callbacked) {
597 		ret = 0;
598 	} else {
599 		if (!ret) {
600 			dev_err(&rspi->ctlr->dev, "DMA timeout\n");
601 			ret = -ETIMEDOUT;
602 		}
603 		if (tx)
604 			dmaengine_terminate_all(rspi->ctlr->dma_tx);
605 		if (rx)
606 			dmaengine_terminate_all(rspi->ctlr->dma_rx);
607 	}
608 
609 	rspi_disable_irq(rspi, irq_mask);
610 
611 	if (tx)
612 		enable_irq(rspi->tx_irq);
613 	if (rx && rspi->rx_irq != other_irq)
614 		enable_irq(rspi->rx_irq);
615 
616 	return ret;
617 
618 no_dma_tx:
619 	if (rx)
620 		dmaengine_terminate_all(rspi->ctlr->dma_rx);
621 no_dma_rx:
622 	if (ret == -EAGAIN) {
623 		pr_warn_once("%s %s: DMA not available, falling back to PIO\n",
624 			     dev_driver_string(&rspi->ctlr->dev),
625 			     dev_name(&rspi->ctlr->dev));
626 	}
627 	return ret;
628 }
629 
630 static void rspi_receive_init(const struct rspi_data *rspi)
631 {
632 	u8 spsr;
633 
634 	spsr = rspi_read8(rspi, RSPI_SPSR);
635 	if (spsr & SPSR_SPRF)
636 		rspi_read_data(rspi);	/* dummy read */
637 	if (spsr & SPSR_OVRF)
638 		rspi_write8(rspi, rspi_read8(rspi, RSPI_SPSR) & ~SPSR_OVRF,
639 			    RSPI_SPSR);
640 }
641 
642 static void rspi_rz_receive_init(const struct rspi_data *rspi)
643 {
644 	rspi_receive_init(rspi);
645 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, RSPI_SPBFCR);
646 	rspi_write8(rspi, 0, RSPI_SPBFCR);
647 }
648 
649 static void qspi_receive_init(const struct rspi_data *rspi)
650 {
651 	u8 spsr;
652 
653 	spsr = rspi_read8(rspi, RSPI_SPSR);
654 	if (spsr & SPSR_SPRF)
655 		rspi_read_data(rspi);   /* dummy read */
656 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
657 	rspi_write8(rspi, 0, QSPI_SPBFCR);
658 }
659 
660 static bool __rspi_can_dma(const struct rspi_data *rspi,
661 			   const struct spi_transfer *xfer)
662 {
663 	return xfer->len > rspi->ops->fifo_size;
664 }
665 
666 static bool rspi_can_dma(struct spi_controller *ctlr, struct spi_device *spi,
667 			 struct spi_transfer *xfer)
668 {
669 	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
670 
671 	return __rspi_can_dma(rspi, xfer);
672 }
673 
674 static int rspi_dma_check_then_transfer(struct rspi_data *rspi,
675 					 struct spi_transfer *xfer)
676 {
677 	if (!rspi->ctlr->can_dma || !__rspi_can_dma(rspi, xfer))
678 		return -EAGAIN;
679 
680 	/* rx_buf can be NULL on RSPI on SH in TX-only Mode */
681 	return rspi_dma_transfer(rspi, &xfer->tx_sg,
682 				xfer->rx_buf ? &xfer->rx_sg : NULL);
683 }
684 
685 static int rspi_common_transfer(struct rspi_data *rspi,
686 				struct spi_transfer *xfer)
687 {
688 	int ret;
689 
690 	ret = rspi_dma_check_then_transfer(rspi, xfer);
691 	if (ret != -EAGAIN)
692 		return ret;
693 
694 	ret = rspi_pio_transfer(rspi, xfer->tx_buf, xfer->rx_buf, xfer->len);
695 	if (ret < 0)
696 		return ret;
697 
698 	/* Wait for the last transmission */
699 	rspi_wait_for_tx_empty(rspi);
700 
701 	return 0;
702 }
703 
704 static int rspi_transfer_one(struct spi_controller *ctlr,
705 			     struct spi_device *spi, struct spi_transfer *xfer)
706 {
707 	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
708 	u8 spcr;
709 
710 	spcr = rspi_read8(rspi, RSPI_SPCR);
711 	if (xfer->rx_buf) {
712 		rspi_receive_init(rspi);
713 		spcr &= ~SPCR_TXMD;
714 	} else {
715 		spcr |= SPCR_TXMD;
716 	}
717 	rspi_write8(rspi, spcr, RSPI_SPCR);
718 
719 	return rspi_common_transfer(rspi, xfer);
720 }
721 
722 static int rspi_rz_transfer_one(struct spi_controller *ctlr,
723 				struct spi_device *spi,
724 				struct spi_transfer *xfer)
725 {
726 	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
727 
728 	rspi_rz_receive_init(rspi);
729 
730 	return rspi_common_transfer(rspi, xfer);
731 }
732 
733 static int qspi_trigger_transfer_out_in(struct rspi_data *rspi, const u8 *tx,
734 					u8 *rx, unsigned int len)
735 {
736 	unsigned int i, n;
737 	int ret;
738 
739 	while (len > 0) {
740 		n = qspi_set_send_trigger(rspi, len);
741 		qspi_set_receive_trigger(rspi, len);
742 		ret = rspi_wait_for_tx_empty(rspi);
743 		if (ret < 0) {
744 			dev_err(&rspi->ctlr->dev, "transmit timeout\n");
745 			return ret;
746 		}
747 		for (i = 0; i < n; i++)
748 			rspi_write_data(rspi, *tx++);
749 
750 		ret = rspi_wait_for_rx_full(rspi);
751 		if (ret < 0) {
752 			dev_err(&rspi->ctlr->dev, "receive timeout\n");
753 			return ret;
754 		}
755 		for (i = 0; i < n; i++)
756 			*rx++ = rspi_read_data(rspi);
757 
758 		len -= n;
759 	}
760 
761 	return 0;
762 }
763 
764 static int qspi_transfer_out_in(struct rspi_data *rspi,
765 				struct spi_transfer *xfer)
766 {
767 	int ret;
768 
769 	qspi_receive_init(rspi);
770 
771 	ret = rspi_dma_check_then_transfer(rspi, xfer);
772 	if (ret != -EAGAIN)
773 		return ret;
774 
775 	return qspi_trigger_transfer_out_in(rspi, xfer->tx_buf,
776 					    xfer->rx_buf, xfer->len);
777 }
778 
779 static int qspi_transfer_out(struct rspi_data *rspi, struct spi_transfer *xfer)
780 {
781 	const u8 *tx = xfer->tx_buf;
782 	unsigned int n = xfer->len;
783 	unsigned int i, len;
784 	int ret;
785 
786 	if (rspi->ctlr->can_dma && __rspi_can_dma(rspi, xfer)) {
787 		ret = rspi_dma_transfer(rspi, &xfer->tx_sg, NULL);
788 		if (ret != -EAGAIN)
789 			return ret;
790 	}
791 
792 	while (n > 0) {
793 		len = qspi_set_send_trigger(rspi, n);
794 		ret = rspi_wait_for_tx_empty(rspi);
795 		if (ret < 0) {
796 			dev_err(&rspi->ctlr->dev, "transmit timeout\n");
797 			return ret;
798 		}
799 		for (i = 0; i < len; i++)
800 			rspi_write_data(rspi, *tx++);
801 
802 		n -= len;
803 	}
804 
805 	/* Wait for the last transmission */
806 	rspi_wait_for_tx_empty(rspi);
807 
808 	return 0;
809 }
810 
811 static int qspi_transfer_in(struct rspi_data *rspi, struct spi_transfer *xfer)
812 {
813 	u8 *rx = xfer->rx_buf;
814 	unsigned int n = xfer->len;
815 	unsigned int i, len;
816 	int ret;
817 
818 	if (rspi->ctlr->can_dma && __rspi_can_dma(rspi, xfer)) {
819 		int ret = rspi_dma_transfer(rspi, NULL, &xfer->rx_sg);
820 		if (ret != -EAGAIN)
821 			return ret;
822 	}
823 
824 	while (n > 0) {
825 		len = qspi_set_receive_trigger(rspi, n);
826 		ret = rspi_wait_for_rx_full(rspi);
827 		if (ret < 0) {
828 			dev_err(&rspi->ctlr->dev, "receive timeout\n");
829 			return ret;
830 		}
831 		for (i = 0; i < len; i++)
832 			*rx++ = rspi_read_data(rspi);
833 
834 		n -= len;
835 	}
836 
837 	return 0;
838 }
839 
840 static int qspi_transfer_one(struct spi_controller *ctlr,
841 			     struct spi_device *spi, struct spi_transfer *xfer)
842 {
843 	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
844 
845 	if (spi->mode & SPI_LOOP) {
846 		return qspi_transfer_out_in(rspi, xfer);
847 	} else if (xfer->tx_nbits > SPI_NBITS_SINGLE) {
848 		/* Quad or Dual SPI Write */
849 		return qspi_transfer_out(rspi, xfer);
850 	} else if (xfer->rx_nbits > SPI_NBITS_SINGLE) {
851 		/* Quad or Dual SPI Read */
852 		return qspi_transfer_in(rspi, xfer);
853 	} else {
854 		/* Single SPI Transfer */
855 		return qspi_transfer_out_in(rspi, xfer);
856 	}
857 }
858 
859 static u16 qspi_transfer_mode(const struct spi_transfer *xfer)
860 {
861 	if (xfer->tx_buf)
862 		switch (xfer->tx_nbits) {
863 		case SPI_NBITS_QUAD:
864 			return SPCMD_SPIMOD_QUAD;
865 		case SPI_NBITS_DUAL:
866 			return SPCMD_SPIMOD_DUAL;
867 		default:
868 			return 0;
869 		}
870 	if (xfer->rx_buf)
871 		switch (xfer->rx_nbits) {
872 		case SPI_NBITS_QUAD:
873 			return SPCMD_SPIMOD_QUAD | SPCMD_SPRW;
874 		case SPI_NBITS_DUAL:
875 			return SPCMD_SPIMOD_DUAL | SPCMD_SPRW;
876 		default:
877 			return 0;
878 		}
879 
880 	return 0;
881 }
882 
883 static int qspi_setup_sequencer(struct rspi_data *rspi,
884 				const struct spi_message *msg)
885 {
886 	const struct spi_transfer *xfer;
887 	unsigned int i = 0, len = 0;
888 	u16 current_mode = 0xffff, mode;
889 
890 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
891 		mode = qspi_transfer_mode(xfer);
892 		if (mode == current_mode) {
893 			len += xfer->len;
894 			continue;
895 		}
896 
897 		/* Transfer mode change */
898 		if (i) {
899 			/* Set transfer data length of previous transfer */
900 			rspi_write32(rspi, len, QSPI_SPBMUL(i - 1));
901 		}
902 
903 		if (i >= QSPI_NUM_SPCMD) {
904 			dev_err(&msg->spi->dev,
905 				"Too many different transfer modes");
906 			return -EINVAL;
907 		}
908 
909 		/* Program transfer mode for this transfer */
910 		rspi_write16(rspi, rspi->spcmd | mode, RSPI_SPCMD(i));
911 		current_mode = mode;
912 		len = xfer->len;
913 		i++;
914 	}
915 	if (i) {
916 		/* Set final transfer data length and sequence length */
917 		rspi_write32(rspi, len, QSPI_SPBMUL(i - 1));
918 		rspi_write8(rspi, i - 1, RSPI_SPSCR);
919 	}
920 
921 	return 0;
922 }
923 
924 static int rspi_prepare_message(struct spi_controller *ctlr,
925 				struct spi_message *msg)
926 {
927 	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
928 	struct spi_device *spi = msg->spi;
929 	int ret;
930 
931 	rspi->max_speed_hz = spi->max_speed_hz;
932 
933 	rspi->spcmd = SPCMD_SSLKP;
934 	if (spi->mode & SPI_CPOL)
935 		rspi->spcmd |= SPCMD_CPOL;
936 	if (spi->mode & SPI_CPHA)
937 		rspi->spcmd |= SPCMD_CPHA;
938 
939 	/* CMOS output mode and MOSI signal from previous transfer */
940 	rspi->sppcr = 0;
941 	if (spi->mode & SPI_LOOP)
942 		rspi->sppcr |= SPPCR_SPLP;
943 
944 	set_config_register(rspi, 8);
945 
946 	if (msg->spi->mode &
947 	    (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD)) {
948 		/* Setup sequencer for messages with multiple transfer modes */
949 		ret = qspi_setup_sequencer(rspi, msg);
950 		if (ret < 0)
951 			return ret;
952 	}
953 
954 	/* Enable SPI function in master mode */
955 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_SPE, RSPI_SPCR);
956 	return 0;
957 }
958 
959 static int rspi_unprepare_message(struct spi_controller *ctlr,
960 				  struct spi_message *msg)
961 {
962 	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
963 
964 	/* Disable SPI function */
965 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_SPE, RSPI_SPCR);
966 
967 	/* Reset sequencer for Single SPI Transfers */
968 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
969 	rspi_write8(rspi, 0, RSPI_SPSCR);
970 	return 0;
971 }
972 
973 static irqreturn_t rspi_irq_mux(int irq, void *_sr)
974 {
975 	struct rspi_data *rspi = _sr;
976 	u8 spsr;
977 	irqreturn_t ret = IRQ_NONE;
978 	u8 disable_irq = 0;
979 
980 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
981 	if (spsr & SPSR_SPRF)
982 		disable_irq |= SPCR_SPRIE;
983 	if (spsr & SPSR_SPTEF)
984 		disable_irq |= SPCR_SPTIE;
985 
986 	if (disable_irq) {
987 		ret = IRQ_HANDLED;
988 		rspi_disable_irq(rspi, disable_irq);
989 		wake_up(&rspi->wait);
990 	}
991 
992 	return ret;
993 }
994 
995 static irqreturn_t rspi_irq_rx(int irq, void *_sr)
996 {
997 	struct rspi_data *rspi = _sr;
998 	u8 spsr;
999 
1000 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
1001 	if (spsr & SPSR_SPRF) {
1002 		rspi_disable_irq(rspi, SPCR_SPRIE);
1003 		wake_up(&rspi->wait);
1004 		return IRQ_HANDLED;
1005 	}
1006 
1007 	return 0;
1008 }
1009 
1010 static irqreturn_t rspi_irq_tx(int irq, void *_sr)
1011 {
1012 	struct rspi_data *rspi = _sr;
1013 	u8 spsr;
1014 
1015 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
1016 	if (spsr & SPSR_SPTEF) {
1017 		rspi_disable_irq(rspi, SPCR_SPTIE);
1018 		wake_up(&rspi->wait);
1019 		return IRQ_HANDLED;
1020 	}
1021 
1022 	return 0;
1023 }
1024 
1025 static struct dma_chan *rspi_request_dma_chan(struct device *dev,
1026 					      enum dma_transfer_direction dir,
1027 					      unsigned int id,
1028 					      dma_addr_t port_addr)
1029 {
1030 	dma_cap_mask_t mask;
1031 	struct dma_chan *chan;
1032 	struct dma_slave_config cfg;
1033 	int ret;
1034 
1035 	dma_cap_zero(mask);
1036 	dma_cap_set(DMA_SLAVE, mask);
1037 
1038 	chan = dma_request_slave_channel_compat(mask, shdma_chan_filter,
1039 				(void *)(unsigned long)id, dev,
1040 				dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1041 	if (!chan) {
1042 		dev_warn(dev, "dma_request_slave_channel_compat failed\n");
1043 		return NULL;
1044 	}
1045 
1046 	memset(&cfg, 0, sizeof(cfg));
1047 	cfg.direction = dir;
1048 	if (dir == DMA_MEM_TO_DEV) {
1049 		cfg.dst_addr = port_addr;
1050 		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1051 	} else {
1052 		cfg.src_addr = port_addr;
1053 		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1054 	}
1055 
1056 	ret = dmaengine_slave_config(chan, &cfg);
1057 	if (ret) {
1058 		dev_warn(dev, "dmaengine_slave_config failed %d\n", ret);
1059 		dma_release_channel(chan);
1060 		return NULL;
1061 	}
1062 
1063 	return chan;
1064 }
1065 
1066 static int rspi_request_dma(struct device *dev, struct spi_controller *ctlr,
1067 			    const struct resource *res)
1068 {
1069 	const struct rspi_plat_data *rspi_pd = dev_get_platdata(dev);
1070 	unsigned int dma_tx_id, dma_rx_id;
1071 
1072 	if (dev->of_node) {
1073 		/* In the OF case we will get the slave IDs from the DT */
1074 		dma_tx_id = 0;
1075 		dma_rx_id = 0;
1076 	} else if (rspi_pd && rspi_pd->dma_tx_id && rspi_pd->dma_rx_id) {
1077 		dma_tx_id = rspi_pd->dma_tx_id;
1078 		dma_rx_id = rspi_pd->dma_rx_id;
1079 	} else {
1080 		/* The driver assumes no error. */
1081 		return 0;
1082 	}
1083 
1084 	ctlr->dma_tx = rspi_request_dma_chan(dev, DMA_MEM_TO_DEV, dma_tx_id,
1085 					     res->start + RSPI_SPDR);
1086 	if (!ctlr->dma_tx)
1087 		return -ENODEV;
1088 
1089 	ctlr->dma_rx = rspi_request_dma_chan(dev, DMA_DEV_TO_MEM, dma_rx_id,
1090 					     res->start + RSPI_SPDR);
1091 	if (!ctlr->dma_rx) {
1092 		dma_release_channel(ctlr->dma_tx);
1093 		ctlr->dma_tx = NULL;
1094 		return -ENODEV;
1095 	}
1096 
1097 	ctlr->can_dma = rspi_can_dma;
1098 	dev_info(dev, "DMA available");
1099 	return 0;
1100 }
1101 
1102 static void rspi_release_dma(struct spi_controller *ctlr)
1103 {
1104 	if (ctlr->dma_tx)
1105 		dma_release_channel(ctlr->dma_tx);
1106 	if (ctlr->dma_rx)
1107 		dma_release_channel(ctlr->dma_rx);
1108 }
1109 
1110 static int rspi_remove(struct platform_device *pdev)
1111 {
1112 	struct rspi_data *rspi = platform_get_drvdata(pdev);
1113 
1114 	rspi_release_dma(rspi->ctlr);
1115 	pm_runtime_disable(&pdev->dev);
1116 
1117 	return 0;
1118 }
1119 
1120 static const struct spi_ops rspi_ops = {
1121 	.set_config_register =	rspi_set_config_register,
1122 	.transfer_one =		rspi_transfer_one,
1123 	.mode_bits =		SPI_CPHA | SPI_CPOL | SPI_LOOP,
1124 	.flags =		SPI_CONTROLLER_MUST_TX,
1125 	.fifo_size =		8,
1126 };
1127 
1128 static const struct spi_ops rspi_rz_ops = {
1129 	.set_config_register =	rspi_rz_set_config_register,
1130 	.transfer_one =		rspi_rz_transfer_one,
1131 	.mode_bits =		SPI_CPHA | SPI_CPOL | SPI_LOOP,
1132 	.flags =		SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX,
1133 	.fifo_size =		8,	/* 8 for TX, 32 for RX */
1134 };
1135 
1136 static const struct spi_ops qspi_ops = {
1137 	.set_config_register =	qspi_set_config_register,
1138 	.transfer_one =		qspi_transfer_one,
1139 	.mode_bits =		SPI_CPHA | SPI_CPOL | SPI_LOOP |
1140 				SPI_TX_DUAL | SPI_TX_QUAD |
1141 				SPI_RX_DUAL | SPI_RX_QUAD,
1142 	.flags =		SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX,
1143 	.fifo_size =		32,
1144 };
1145 
1146 #ifdef CONFIG_OF
1147 static const struct of_device_id rspi_of_match[] = {
1148 	/* RSPI on legacy SH */
1149 	{ .compatible = "renesas,rspi", .data = &rspi_ops },
1150 	/* RSPI on RZ/A1H */
1151 	{ .compatible = "renesas,rspi-rz", .data = &rspi_rz_ops },
1152 	/* QSPI on R-Car Gen2 */
1153 	{ .compatible = "renesas,qspi", .data = &qspi_ops },
1154 	{ /* sentinel */ }
1155 };
1156 
1157 MODULE_DEVICE_TABLE(of, rspi_of_match);
1158 
1159 static int rspi_parse_dt(struct device *dev, struct spi_controller *ctlr)
1160 {
1161 	u32 num_cs;
1162 	int error;
1163 
1164 	/* Parse DT properties */
1165 	error = of_property_read_u32(dev->of_node, "num-cs", &num_cs);
1166 	if (error) {
1167 		dev_err(dev, "of_property_read_u32 num-cs failed %d\n", error);
1168 		return error;
1169 	}
1170 
1171 	ctlr->num_chipselect = num_cs;
1172 	return 0;
1173 }
1174 #else
1175 #define rspi_of_match	NULL
1176 static inline int rspi_parse_dt(struct device *dev, struct spi_controller *ctlr)
1177 {
1178 	return -EINVAL;
1179 }
1180 #endif /* CONFIG_OF */
1181 
1182 static int rspi_request_irq(struct device *dev, unsigned int irq,
1183 			    irq_handler_t handler, const char *suffix,
1184 			    void *dev_id)
1185 {
1186 	const char *name = devm_kasprintf(dev, GFP_KERNEL, "%s:%s",
1187 					  dev_name(dev), suffix);
1188 	if (!name)
1189 		return -ENOMEM;
1190 
1191 	return devm_request_irq(dev, irq, handler, 0, name, dev_id);
1192 }
1193 
1194 static int rspi_probe(struct platform_device *pdev)
1195 {
1196 	struct resource *res;
1197 	struct spi_controller *ctlr;
1198 	struct rspi_data *rspi;
1199 	int ret;
1200 	const struct rspi_plat_data *rspi_pd;
1201 	const struct spi_ops *ops;
1202 
1203 	ctlr = spi_alloc_master(&pdev->dev, sizeof(struct rspi_data));
1204 	if (ctlr == NULL)
1205 		return -ENOMEM;
1206 
1207 	ops = of_device_get_match_data(&pdev->dev);
1208 	if (ops) {
1209 		ret = rspi_parse_dt(&pdev->dev, ctlr);
1210 		if (ret)
1211 			goto error1;
1212 	} else {
1213 		ops = (struct spi_ops *)pdev->id_entry->driver_data;
1214 		rspi_pd = dev_get_platdata(&pdev->dev);
1215 		if (rspi_pd && rspi_pd->num_chipselect)
1216 			ctlr->num_chipselect = rspi_pd->num_chipselect;
1217 		else
1218 			ctlr->num_chipselect = 2; /* default */
1219 	}
1220 
1221 	/* ops parameter check */
1222 	if (!ops->set_config_register) {
1223 		dev_err(&pdev->dev, "there is no set_config_register\n");
1224 		ret = -ENODEV;
1225 		goto error1;
1226 	}
1227 
1228 	rspi = spi_controller_get_devdata(ctlr);
1229 	platform_set_drvdata(pdev, rspi);
1230 	rspi->ops = ops;
1231 	rspi->ctlr = ctlr;
1232 
1233 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1234 	rspi->addr = devm_ioremap_resource(&pdev->dev, res);
1235 	if (IS_ERR(rspi->addr)) {
1236 		ret = PTR_ERR(rspi->addr);
1237 		goto error1;
1238 	}
1239 
1240 	rspi->clk = devm_clk_get(&pdev->dev, NULL);
1241 	if (IS_ERR(rspi->clk)) {
1242 		dev_err(&pdev->dev, "cannot get clock\n");
1243 		ret = PTR_ERR(rspi->clk);
1244 		goto error1;
1245 	}
1246 
1247 	pm_runtime_enable(&pdev->dev);
1248 
1249 	init_waitqueue_head(&rspi->wait);
1250 
1251 	ctlr->bus_num = pdev->id;
1252 	ctlr->auto_runtime_pm = true;
1253 	ctlr->transfer_one = ops->transfer_one;
1254 	ctlr->prepare_message = rspi_prepare_message;
1255 	ctlr->unprepare_message = rspi_unprepare_message;
1256 	ctlr->mode_bits = ops->mode_bits;
1257 	ctlr->flags = ops->flags;
1258 	ctlr->dev.of_node = pdev->dev.of_node;
1259 
1260 	ret = platform_get_irq_byname_optional(pdev, "rx");
1261 	if (ret < 0) {
1262 		ret = platform_get_irq_byname_optional(pdev, "mux");
1263 		if (ret < 0)
1264 			ret = platform_get_irq(pdev, 0);
1265 		if (ret >= 0)
1266 			rspi->rx_irq = rspi->tx_irq = ret;
1267 	} else {
1268 		rspi->rx_irq = ret;
1269 		ret = platform_get_irq_byname(pdev, "tx");
1270 		if (ret >= 0)
1271 			rspi->tx_irq = ret;
1272 	}
1273 
1274 	if (rspi->rx_irq == rspi->tx_irq) {
1275 		/* Single multiplexed interrupt */
1276 		ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_mux,
1277 				       "mux", rspi);
1278 	} else {
1279 		/* Multi-interrupt mode, only SPRI and SPTI are used */
1280 		ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_rx,
1281 				       "rx", rspi);
1282 		if (!ret)
1283 			ret = rspi_request_irq(&pdev->dev, rspi->tx_irq,
1284 					       rspi_irq_tx, "tx", rspi);
1285 	}
1286 	if (ret < 0) {
1287 		dev_err(&pdev->dev, "request_irq error\n");
1288 		goto error2;
1289 	}
1290 
1291 	ret = rspi_request_dma(&pdev->dev, ctlr, res);
1292 	if (ret < 0)
1293 		dev_warn(&pdev->dev, "DMA not available, using PIO\n");
1294 
1295 	ret = devm_spi_register_controller(&pdev->dev, ctlr);
1296 	if (ret < 0) {
1297 		dev_err(&pdev->dev, "devm_spi_register_controller error.\n");
1298 		goto error3;
1299 	}
1300 
1301 	dev_info(&pdev->dev, "probed\n");
1302 
1303 	return 0;
1304 
1305 error3:
1306 	rspi_release_dma(ctlr);
1307 error2:
1308 	pm_runtime_disable(&pdev->dev);
1309 error1:
1310 	spi_controller_put(ctlr);
1311 
1312 	return ret;
1313 }
1314 
1315 static const struct platform_device_id spi_driver_ids[] = {
1316 	{ "rspi",	(kernel_ulong_t)&rspi_ops },
1317 	{ "rspi-rz",	(kernel_ulong_t)&rspi_rz_ops },
1318 	{ "qspi",	(kernel_ulong_t)&qspi_ops },
1319 	{},
1320 };
1321 
1322 MODULE_DEVICE_TABLE(platform, spi_driver_ids);
1323 
1324 #ifdef CONFIG_PM_SLEEP
1325 static int rspi_suspend(struct device *dev)
1326 {
1327 	struct rspi_data *rspi = dev_get_drvdata(dev);
1328 
1329 	return spi_controller_suspend(rspi->ctlr);
1330 }
1331 
1332 static int rspi_resume(struct device *dev)
1333 {
1334 	struct rspi_data *rspi = dev_get_drvdata(dev);
1335 
1336 	return spi_controller_resume(rspi->ctlr);
1337 }
1338 
1339 static SIMPLE_DEV_PM_OPS(rspi_pm_ops, rspi_suspend, rspi_resume);
1340 #define DEV_PM_OPS	&rspi_pm_ops
1341 #else
1342 #define DEV_PM_OPS	NULL
1343 #endif /* CONFIG_PM_SLEEP */
1344 
1345 static struct platform_driver rspi_driver = {
1346 	.probe =	rspi_probe,
1347 	.remove =	rspi_remove,
1348 	.id_table =	spi_driver_ids,
1349 	.driver		= {
1350 		.name = "renesas_spi",
1351 		.pm = DEV_PM_OPS,
1352 		.of_match_table = of_match_ptr(rspi_of_match),
1353 	},
1354 };
1355 module_platform_driver(rspi_driver);
1356 
1357 MODULE_DESCRIPTION("Renesas RSPI bus driver");
1358 MODULE_LICENSE("GPL v2");
1359 MODULE_AUTHOR("Yoshihiro Shimoda");
1360 MODULE_ALIAS("platform:rspi");
1361