xref: /openbmc/linux/drivers/spi/spi-rspi.c (revision 3e30a927)
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(i)		((i) << 4)	/* SSL Assert Signal Setting */
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 	u8 num_hw_ss;
246 };
247 
248 /*
249  * functions for RSPI on legacy SH
250  */
251 static int rspi_set_config_register(struct rspi_data *rspi, int access_size)
252 {
253 	int spbr;
254 
255 	/* Sets output mode, MOSI signal, and (optionally) loopback */
256 	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
257 
258 	/* Sets transfer bit rate */
259 	spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk),
260 			    2 * rspi->max_speed_hz) - 1;
261 	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
262 
263 	/* Disable dummy transmission, set 16-bit word access, 1 frame */
264 	rspi_write8(rspi, 0, RSPI_SPDCR);
265 	rspi->byte_access = 0;
266 
267 	/* Sets RSPCK, SSL, next-access delay value */
268 	rspi_write8(rspi, 0x00, RSPI_SPCKD);
269 	rspi_write8(rspi, 0x00, RSPI_SSLND);
270 	rspi_write8(rspi, 0x00, RSPI_SPND);
271 
272 	/* Sets parity, interrupt mask */
273 	rspi_write8(rspi, 0x00, RSPI_SPCR2);
274 
275 	/* Resets sequencer */
276 	rspi_write8(rspi, 0, RSPI_SPSCR);
277 	rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size);
278 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
279 
280 	/* Sets RSPI mode */
281 	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
282 
283 	return 0;
284 }
285 
286 /*
287  * functions for RSPI on RZ
288  */
289 static int rspi_rz_set_config_register(struct rspi_data *rspi, int access_size)
290 {
291 	int spbr;
292 	int div = 0;
293 	unsigned long clksrc;
294 
295 	/* Sets output mode, MOSI signal, and (optionally) loopback */
296 	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
297 
298 	clksrc = clk_get_rate(rspi->clk);
299 	while (div < 3) {
300 		if (rspi->max_speed_hz >= clksrc/4) /* 4=(CLK/2)/2 */
301 			break;
302 		div++;
303 		clksrc /= 2;
304 	}
305 
306 	/* Sets transfer bit rate */
307 	spbr = DIV_ROUND_UP(clksrc, 2 * rspi->max_speed_hz) - 1;
308 	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
309 	rspi->spcmd |= div << 2;
310 
311 	/* Disable dummy transmission, set byte access */
312 	rspi_write8(rspi, SPDCR_SPLBYTE, RSPI_SPDCR);
313 	rspi->byte_access = 1;
314 
315 	/* Sets RSPCK, SSL, next-access delay value */
316 	rspi_write8(rspi, 0x00, RSPI_SPCKD);
317 	rspi_write8(rspi, 0x00, RSPI_SSLND);
318 	rspi_write8(rspi, 0x00, RSPI_SPND);
319 
320 	/* Resets sequencer */
321 	rspi_write8(rspi, 0, RSPI_SPSCR);
322 	rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size);
323 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
324 
325 	/* Sets RSPI mode */
326 	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
327 
328 	return 0;
329 }
330 
331 /*
332  * functions for QSPI
333  */
334 static int qspi_set_config_register(struct rspi_data *rspi, int access_size)
335 {
336 	int spbr;
337 
338 	/* Sets output mode, MOSI signal, and (optionally) loopback */
339 	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
340 
341 	/* Sets transfer bit rate */
342 	spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk), 2 * rspi->max_speed_hz);
343 	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
344 
345 	/* Disable dummy transmission, set byte access */
346 	rspi_write8(rspi, 0, RSPI_SPDCR);
347 	rspi->byte_access = 1;
348 
349 	/* Sets RSPCK, SSL, next-access delay value */
350 	rspi_write8(rspi, 0x00, RSPI_SPCKD);
351 	rspi_write8(rspi, 0x00, RSPI_SSLND);
352 	rspi_write8(rspi, 0x00, RSPI_SPND);
353 
354 	/* Data Length Setting */
355 	if (access_size == 8)
356 		rspi->spcmd |= SPCMD_SPB_8BIT;
357 	else if (access_size == 16)
358 		rspi->spcmd |= SPCMD_SPB_16BIT;
359 	else
360 		rspi->spcmd |= SPCMD_SPB_32BIT;
361 
362 	rspi->spcmd |= SPCMD_SCKDEN | SPCMD_SLNDEN | SPCMD_SPNDEN;
363 
364 	/* Resets transfer data length */
365 	rspi_write32(rspi, 0, QSPI_SPBMUL0);
366 
367 	/* Resets transmit and receive buffer */
368 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
369 	/* Sets buffer to allow normal operation */
370 	rspi_write8(rspi, 0x00, QSPI_SPBFCR);
371 
372 	/* Resets sequencer */
373 	rspi_write8(rspi, 0, RSPI_SPSCR);
374 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
375 
376 	/* Sets RSPI mode */
377 	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
378 
379 	return 0;
380 }
381 
382 static void qspi_update(const struct rspi_data *rspi, u8 mask, u8 val, u8 reg)
383 {
384 	u8 data;
385 
386 	data = rspi_read8(rspi, reg);
387 	data &= ~mask;
388 	data |= (val & mask);
389 	rspi_write8(rspi, data, reg);
390 }
391 
392 static unsigned int qspi_set_send_trigger(struct rspi_data *rspi,
393 					  unsigned int len)
394 {
395 	unsigned int n;
396 
397 	n = min(len, QSPI_BUFFER_SIZE);
398 
399 	if (len >= QSPI_BUFFER_SIZE) {
400 		/* sets triggering number to 32 bytes */
401 		qspi_update(rspi, SPBFCR_TXTRG_MASK,
402 			     SPBFCR_TXTRG_32B, QSPI_SPBFCR);
403 	} else {
404 		/* sets triggering number to 1 byte */
405 		qspi_update(rspi, SPBFCR_TXTRG_MASK,
406 			     SPBFCR_TXTRG_1B, QSPI_SPBFCR);
407 	}
408 
409 	return n;
410 }
411 
412 static int qspi_set_receive_trigger(struct rspi_data *rspi, unsigned int len)
413 {
414 	unsigned int n;
415 
416 	n = min(len, QSPI_BUFFER_SIZE);
417 
418 	if (len >= QSPI_BUFFER_SIZE) {
419 		/* sets triggering number to 32 bytes */
420 		qspi_update(rspi, SPBFCR_RXTRG_MASK,
421 			     SPBFCR_RXTRG_32B, QSPI_SPBFCR);
422 	} else {
423 		/* sets triggering number to 1 byte */
424 		qspi_update(rspi, SPBFCR_RXTRG_MASK,
425 			     SPBFCR_RXTRG_1B, QSPI_SPBFCR);
426 	}
427 	return n;
428 }
429 
430 static void rspi_enable_irq(const struct rspi_data *rspi, u8 enable)
431 {
432 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | enable, RSPI_SPCR);
433 }
434 
435 static void rspi_disable_irq(const struct rspi_data *rspi, u8 disable)
436 {
437 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~disable, RSPI_SPCR);
438 }
439 
440 static int rspi_wait_for_interrupt(struct rspi_data *rspi, u8 wait_mask,
441 				   u8 enable_bit)
442 {
443 	int ret;
444 
445 	rspi->spsr = rspi_read8(rspi, RSPI_SPSR);
446 	if (rspi->spsr & wait_mask)
447 		return 0;
448 
449 	rspi_enable_irq(rspi, enable_bit);
450 	ret = wait_event_timeout(rspi->wait, rspi->spsr & wait_mask, HZ);
451 	if (ret == 0 && !(rspi->spsr & wait_mask))
452 		return -ETIMEDOUT;
453 
454 	return 0;
455 }
456 
457 static inline int rspi_wait_for_tx_empty(struct rspi_data *rspi)
458 {
459 	return rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
460 }
461 
462 static inline int rspi_wait_for_rx_full(struct rspi_data *rspi)
463 {
464 	return rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE);
465 }
466 
467 static int rspi_data_out(struct rspi_data *rspi, u8 data)
468 {
469 	int error = rspi_wait_for_tx_empty(rspi);
470 	if (error < 0) {
471 		dev_err(&rspi->ctlr->dev, "transmit timeout\n");
472 		return error;
473 	}
474 	rspi_write_data(rspi, data);
475 	return 0;
476 }
477 
478 static int rspi_data_in(struct rspi_data *rspi)
479 {
480 	int error;
481 	u8 data;
482 
483 	error = rspi_wait_for_rx_full(rspi);
484 	if (error < 0) {
485 		dev_err(&rspi->ctlr->dev, "receive timeout\n");
486 		return error;
487 	}
488 	data = rspi_read_data(rspi);
489 	return data;
490 }
491 
492 static int rspi_pio_transfer(struct rspi_data *rspi, const u8 *tx, u8 *rx,
493 			     unsigned int n)
494 {
495 	while (n-- > 0) {
496 		if (tx) {
497 			int ret = rspi_data_out(rspi, *tx++);
498 			if (ret < 0)
499 				return ret;
500 		}
501 		if (rx) {
502 			int ret = rspi_data_in(rspi);
503 			if (ret < 0)
504 				return ret;
505 			*rx++ = ret;
506 		}
507 	}
508 
509 	return 0;
510 }
511 
512 static void rspi_dma_complete(void *arg)
513 {
514 	struct rspi_data *rspi = arg;
515 
516 	rspi->dma_callbacked = 1;
517 	wake_up_interruptible(&rspi->wait);
518 }
519 
520 static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
521 			     struct sg_table *rx)
522 {
523 	struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL;
524 	u8 irq_mask = 0;
525 	unsigned int other_irq = 0;
526 	dma_cookie_t cookie;
527 	int ret;
528 
529 	/* First prepare and submit the DMA request(s), as this may fail */
530 	if (rx) {
531 		desc_rx = dmaengine_prep_slave_sg(rspi->ctlr->dma_rx, rx->sgl,
532 					rx->nents, DMA_DEV_TO_MEM,
533 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
534 		if (!desc_rx) {
535 			ret = -EAGAIN;
536 			goto no_dma_rx;
537 		}
538 
539 		desc_rx->callback = rspi_dma_complete;
540 		desc_rx->callback_param = rspi;
541 		cookie = dmaengine_submit(desc_rx);
542 		if (dma_submit_error(cookie)) {
543 			ret = cookie;
544 			goto no_dma_rx;
545 		}
546 
547 		irq_mask |= SPCR_SPRIE;
548 	}
549 
550 	if (tx) {
551 		desc_tx = dmaengine_prep_slave_sg(rspi->ctlr->dma_tx, tx->sgl,
552 					tx->nents, DMA_MEM_TO_DEV,
553 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
554 		if (!desc_tx) {
555 			ret = -EAGAIN;
556 			goto no_dma_tx;
557 		}
558 
559 		if (rx) {
560 			/* No callback */
561 			desc_tx->callback = NULL;
562 		} else {
563 			desc_tx->callback = rspi_dma_complete;
564 			desc_tx->callback_param = rspi;
565 		}
566 		cookie = dmaengine_submit(desc_tx);
567 		if (dma_submit_error(cookie)) {
568 			ret = cookie;
569 			goto no_dma_tx;
570 		}
571 
572 		irq_mask |= SPCR_SPTIE;
573 	}
574 
575 	/*
576 	 * DMAC needs SPxIE, but if SPxIE is set, the IRQ routine will be
577 	 * called. So, this driver disables the IRQ while DMA transfer.
578 	 */
579 	if (tx)
580 		disable_irq(other_irq = rspi->tx_irq);
581 	if (rx && rspi->rx_irq != other_irq)
582 		disable_irq(rspi->rx_irq);
583 
584 	rspi_enable_irq(rspi, irq_mask);
585 	rspi->dma_callbacked = 0;
586 
587 	/* Now start DMA */
588 	if (rx)
589 		dma_async_issue_pending(rspi->ctlr->dma_rx);
590 	if (tx)
591 		dma_async_issue_pending(rspi->ctlr->dma_tx);
592 
593 	ret = wait_event_interruptible_timeout(rspi->wait,
594 					       rspi->dma_callbacked, HZ);
595 	if (ret > 0 && rspi->dma_callbacked) {
596 		ret = 0;
597 	} else {
598 		if (!ret) {
599 			dev_err(&rspi->ctlr->dev, "DMA timeout\n");
600 			ret = -ETIMEDOUT;
601 		}
602 		if (tx)
603 			dmaengine_terminate_all(rspi->ctlr->dma_tx);
604 		if (rx)
605 			dmaengine_terminate_all(rspi->ctlr->dma_rx);
606 	}
607 
608 	rspi_disable_irq(rspi, irq_mask);
609 
610 	if (tx)
611 		enable_irq(rspi->tx_irq);
612 	if (rx && rspi->rx_irq != other_irq)
613 		enable_irq(rspi->rx_irq);
614 
615 	return ret;
616 
617 no_dma_tx:
618 	if (rx)
619 		dmaengine_terminate_all(rspi->ctlr->dma_rx);
620 no_dma_rx:
621 	if (ret == -EAGAIN) {
622 		dev_warn_once(&rspi->ctlr->dev,
623 			      "DMA not available, falling back to PIO\n");
624 	}
625 	return ret;
626 }
627 
628 static void rspi_receive_init(const struct rspi_data *rspi)
629 {
630 	u8 spsr;
631 
632 	spsr = rspi_read8(rspi, RSPI_SPSR);
633 	if (spsr & SPSR_SPRF)
634 		rspi_read_data(rspi);	/* dummy read */
635 	if (spsr & SPSR_OVRF)
636 		rspi_write8(rspi, rspi_read8(rspi, RSPI_SPSR) & ~SPSR_OVRF,
637 			    RSPI_SPSR);
638 }
639 
640 static void rspi_rz_receive_init(const struct rspi_data *rspi)
641 {
642 	rspi_receive_init(rspi);
643 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, RSPI_SPBFCR);
644 	rspi_write8(rspi, 0, RSPI_SPBFCR);
645 }
646 
647 static void qspi_receive_init(const struct rspi_data *rspi)
648 {
649 	u8 spsr;
650 
651 	spsr = rspi_read8(rspi, RSPI_SPSR);
652 	if (spsr & SPSR_SPRF)
653 		rspi_read_data(rspi);   /* dummy read */
654 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
655 	rspi_write8(rspi, 0, QSPI_SPBFCR);
656 }
657 
658 static bool __rspi_can_dma(const struct rspi_data *rspi,
659 			   const struct spi_transfer *xfer)
660 {
661 	return xfer->len > rspi->ops->fifo_size;
662 }
663 
664 static bool rspi_can_dma(struct spi_controller *ctlr, struct spi_device *spi,
665 			 struct spi_transfer *xfer)
666 {
667 	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
668 
669 	return __rspi_can_dma(rspi, xfer);
670 }
671 
672 static int rspi_dma_check_then_transfer(struct rspi_data *rspi,
673 					 struct spi_transfer *xfer)
674 {
675 	if (!rspi->ctlr->can_dma || !__rspi_can_dma(rspi, xfer))
676 		return -EAGAIN;
677 
678 	/* rx_buf can be NULL on RSPI on SH in TX-only Mode */
679 	return rspi_dma_transfer(rspi, &xfer->tx_sg,
680 				xfer->rx_buf ? &xfer->rx_sg : NULL);
681 }
682 
683 static int rspi_common_transfer(struct rspi_data *rspi,
684 				struct spi_transfer *xfer)
685 {
686 	int ret;
687 
688 	ret = rspi_dma_check_then_transfer(rspi, xfer);
689 	if (ret != -EAGAIN)
690 		return ret;
691 
692 	ret = rspi_pio_transfer(rspi, xfer->tx_buf, xfer->rx_buf, xfer->len);
693 	if (ret < 0)
694 		return ret;
695 
696 	/* Wait for the last transmission */
697 	rspi_wait_for_tx_empty(rspi);
698 
699 	return 0;
700 }
701 
702 static int rspi_transfer_one(struct spi_controller *ctlr,
703 			     struct spi_device *spi, struct spi_transfer *xfer)
704 {
705 	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
706 	u8 spcr;
707 
708 	spcr = rspi_read8(rspi, RSPI_SPCR);
709 	if (xfer->rx_buf) {
710 		rspi_receive_init(rspi);
711 		spcr &= ~SPCR_TXMD;
712 	} else {
713 		spcr |= SPCR_TXMD;
714 	}
715 	rspi_write8(rspi, spcr, RSPI_SPCR);
716 
717 	return rspi_common_transfer(rspi, xfer);
718 }
719 
720 static int rspi_rz_transfer_one(struct spi_controller *ctlr,
721 				struct spi_device *spi,
722 				struct spi_transfer *xfer)
723 {
724 	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
725 
726 	rspi_rz_receive_init(rspi);
727 
728 	return rspi_common_transfer(rspi, xfer);
729 }
730 
731 static int qspi_trigger_transfer_out_in(struct rspi_data *rspi, const u8 *tx,
732 					u8 *rx, unsigned int len)
733 {
734 	unsigned int i, n;
735 	int ret;
736 
737 	while (len > 0) {
738 		n = qspi_set_send_trigger(rspi, len);
739 		qspi_set_receive_trigger(rspi, len);
740 		ret = rspi_wait_for_tx_empty(rspi);
741 		if (ret < 0) {
742 			dev_err(&rspi->ctlr->dev, "transmit timeout\n");
743 			return ret;
744 		}
745 		for (i = 0; i < n; i++)
746 			rspi_write_data(rspi, *tx++);
747 
748 		ret = rspi_wait_for_rx_full(rspi);
749 		if (ret < 0) {
750 			dev_err(&rspi->ctlr->dev, "receive timeout\n");
751 			return ret;
752 		}
753 		for (i = 0; i < n; i++)
754 			*rx++ = rspi_read_data(rspi);
755 
756 		len -= n;
757 	}
758 
759 	return 0;
760 }
761 
762 static int qspi_transfer_out_in(struct rspi_data *rspi,
763 				struct spi_transfer *xfer)
764 {
765 	int ret;
766 
767 	qspi_receive_init(rspi);
768 
769 	ret = rspi_dma_check_then_transfer(rspi, xfer);
770 	if (ret != -EAGAIN)
771 		return ret;
772 
773 	return qspi_trigger_transfer_out_in(rspi, xfer->tx_buf,
774 					    xfer->rx_buf, xfer->len);
775 }
776 
777 static int qspi_transfer_out(struct rspi_data *rspi, struct spi_transfer *xfer)
778 {
779 	const u8 *tx = xfer->tx_buf;
780 	unsigned int n = xfer->len;
781 	unsigned int i, len;
782 	int ret;
783 
784 	if (rspi->ctlr->can_dma && __rspi_can_dma(rspi, xfer)) {
785 		ret = rspi_dma_transfer(rspi, &xfer->tx_sg, NULL);
786 		if (ret != -EAGAIN)
787 			return ret;
788 	}
789 
790 	while (n > 0) {
791 		len = qspi_set_send_trigger(rspi, n);
792 		ret = rspi_wait_for_tx_empty(rspi);
793 		if (ret < 0) {
794 			dev_err(&rspi->ctlr->dev, "transmit timeout\n");
795 			return ret;
796 		}
797 		for (i = 0; i < len; i++)
798 			rspi_write_data(rspi, *tx++);
799 
800 		n -= len;
801 	}
802 
803 	/* Wait for the last transmission */
804 	rspi_wait_for_tx_empty(rspi);
805 
806 	return 0;
807 }
808 
809 static int qspi_transfer_in(struct rspi_data *rspi, struct spi_transfer *xfer)
810 {
811 	u8 *rx = xfer->rx_buf;
812 	unsigned int n = xfer->len;
813 	unsigned int i, len;
814 	int ret;
815 
816 	if (rspi->ctlr->can_dma && __rspi_can_dma(rspi, xfer)) {
817 		int ret = rspi_dma_transfer(rspi, NULL, &xfer->rx_sg);
818 		if (ret != -EAGAIN)
819 			return ret;
820 	}
821 
822 	while (n > 0) {
823 		len = qspi_set_receive_trigger(rspi, n);
824 		ret = rspi_wait_for_rx_full(rspi);
825 		if (ret < 0) {
826 			dev_err(&rspi->ctlr->dev, "receive timeout\n");
827 			return ret;
828 		}
829 		for (i = 0; i < len; i++)
830 			*rx++ = rspi_read_data(rspi);
831 
832 		n -= len;
833 	}
834 
835 	return 0;
836 }
837 
838 static int qspi_transfer_one(struct spi_controller *ctlr,
839 			     struct spi_device *spi, struct spi_transfer *xfer)
840 {
841 	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
842 
843 	if (spi->mode & SPI_LOOP) {
844 		return qspi_transfer_out_in(rspi, xfer);
845 	} else if (xfer->tx_nbits > SPI_NBITS_SINGLE) {
846 		/* Quad or Dual SPI Write */
847 		return qspi_transfer_out(rspi, xfer);
848 	} else if (xfer->rx_nbits > SPI_NBITS_SINGLE) {
849 		/* Quad or Dual SPI Read */
850 		return qspi_transfer_in(rspi, xfer);
851 	} else {
852 		/* Single SPI Transfer */
853 		return qspi_transfer_out_in(rspi, xfer);
854 	}
855 }
856 
857 static u16 qspi_transfer_mode(const struct spi_transfer *xfer)
858 {
859 	if (xfer->tx_buf)
860 		switch (xfer->tx_nbits) {
861 		case SPI_NBITS_QUAD:
862 			return SPCMD_SPIMOD_QUAD;
863 		case SPI_NBITS_DUAL:
864 			return SPCMD_SPIMOD_DUAL;
865 		default:
866 			return 0;
867 		}
868 	if (xfer->rx_buf)
869 		switch (xfer->rx_nbits) {
870 		case SPI_NBITS_QUAD:
871 			return SPCMD_SPIMOD_QUAD | SPCMD_SPRW;
872 		case SPI_NBITS_DUAL:
873 			return SPCMD_SPIMOD_DUAL | SPCMD_SPRW;
874 		default:
875 			return 0;
876 		}
877 
878 	return 0;
879 }
880 
881 static int qspi_setup_sequencer(struct rspi_data *rspi,
882 				const struct spi_message *msg)
883 {
884 	const struct spi_transfer *xfer;
885 	unsigned int i = 0, len = 0;
886 	u16 current_mode = 0xffff, mode;
887 
888 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
889 		mode = qspi_transfer_mode(xfer);
890 		if (mode == current_mode) {
891 			len += xfer->len;
892 			continue;
893 		}
894 
895 		/* Transfer mode change */
896 		if (i) {
897 			/* Set transfer data length of previous transfer */
898 			rspi_write32(rspi, len, QSPI_SPBMUL(i - 1));
899 		}
900 
901 		if (i >= QSPI_NUM_SPCMD) {
902 			dev_err(&msg->spi->dev,
903 				"Too many different transfer modes");
904 			return -EINVAL;
905 		}
906 
907 		/* Program transfer mode for this transfer */
908 		rspi_write16(rspi, rspi->spcmd | mode, RSPI_SPCMD(i));
909 		current_mode = mode;
910 		len = xfer->len;
911 		i++;
912 	}
913 	if (i) {
914 		/* Set final transfer data length and sequence length */
915 		rspi_write32(rspi, len, QSPI_SPBMUL(i - 1));
916 		rspi_write8(rspi, i - 1, RSPI_SPSCR);
917 	}
918 
919 	return 0;
920 }
921 
922 static int rspi_prepare_message(struct spi_controller *ctlr,
923 				struct spi_message *msg)
924 {
925 	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
926 	struct spi_device *spi = msg->spi;
927 	int ret;
928 
929 	rspi->max_speed_hz = spi->max_speed_hz;
930 
931 	rspi->spcmd = SPCMD_SSLKP;
932 	if (spi->mode & SPI_CPOL)
933 		rspi->spcmd |= SPCMD_CPOL;
934 	if (spi->mode & SPI_CPHA)
935 		rspi->spcmd |= SPCMD_CPHA;
936 
937 	/* Configure slave signal to assert */
938 	rspi->spcmd |= SPCMD_SSLA(spi->cs_gpiod ? rspi->ctlr->unused_native_cs
939 						: spi->chip_select);
940 
941 	/* CMOS output mode and MOSI signal from previous transfer */
942 	rspi->sppcr = 0;
943 	if (spi->mode & SPI_LOOP)
944 		rspi->sppcr |= SPPCR_SPLP;
945 
946 	rspi->ops->set_config_register(rspi, 8);
947 
948 	if (msg->spi->mode &
949 	    (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD)) {
950 		/* Setup sequencer for messages with multiple transfer modes */
951 		ret = qspi_setup_sequencer(rspi, msg);
952 		if (ret < 0)
953 			return ret;
954 	}
955 
956 	/* Enable SPI function in master mode */
957 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_SPE, RSPI_SPCR);
958 	return 0;
959 }
960 
961 static int rspi_unprepare_message(struct spi_controller *ctlr,
962 				  struct spi_message *msg)
963 {
964 	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
965 
966 	/* Disable SPI function */
967 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_SPE, RSPI_SPCR);
968 
969 	/* Reset sequencer for Single SPI Transfers */
970 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
971 	rspi_write8(rspi, 0, RSPI_SPSCR);
972 	return 0;
973 }
974 
975 static irqreturn_t rspi_irq_mux(int irq, void *_sr)
976 {
977 	struct rspi_data *rspi = _sr;
978 	u8 spsr;
979 	irqreturn_t ret = IRQ_NONE;
980 	u8 disable_irq = 0;
981 
982 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
983 	if (spsr & SPSR_SPRF)
984 		disable_irq |= SPCR_SPRIE;
985 	if (spsr & SPSR_SPTEF)
986 		disable_irq |= SPCR_SPTIE;
987 
988 	if (disable_irq) {
989 		ret = IRQ_HANDLED;
990 		rspi_disable_irq(rspi, disable_irq);
991 		wake_up(&rspi->wait);
992 	}
993 
994 	return ret;
995 }
996 
997 static irqreturn_t rspi_irq_rx(int irq, void *_sr)
998 {
999 	struct rspi_data *rspi = _sr;
1000 	u8 spsr;
1001 
1002 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
1003 	if (spsr & SPSR_SPRF) {
1004 		rspi_disable_irq(rspi, SPCR_SPRIE);
1005 		wake_up(&rspi->wait);
1006 		return IRQ_HANDLED;
1007 	}
1008 
1009 	return 0;
1010 }
1011 
1012 static irqreturn_t rspi_irq_tx(int irq, void *_sr)
1013 {
1014 	struct rspi_data *rspi = _sr;
1015 	u8 spsr;
1016 
1017 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
1018 	if (spsr & SPSR_SPTEF) {
1019 		rspi_disable_irq(rspi, SPCR_SPTIE);
1020 		wake_up(&rspi->wait);
1021 		return IRQ_HANDLED;
1022 	}
1023 
1024 	return 0;
1025 }
1026 
1027 static struct dma_chan *rspi_request_dma_chan(struct device *dev,
1028 					      enum dma_transfer_direction dir,
1029 					      unsigned int id,
1030 					      dma_addr_t port_addr)
1031 {
1032 	dma_cap_mask_t mask;
1033 	struct dma_chan *chan;
1034 	struct dma_slave_config cfg;
1035 	int ret;
1036 
1037 	dma_cap_zero(mask);
1038 	dma_cap_set(DMA_SLAVE, mask);
1039 
1040 	chan = dma_request_slave_channel_compat(mask, shdma_chan_filter,
1041 				(void *)(unsigned long)id, dev,
1042 				dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1043 	if (!chan) {
1044 		dev_warn(dev, "dma_request_slave_channel_compat failed\n");
1045 		return NULL;
1046 	}
1047 
1048 	memset(&cfg, 0, sizeof(cfg));
1049 	cfg.direction = dir;
1050 	if (dir == DMA_MEM_TO_DEV) {
1051 		cfg.dst_addr = port_addr;
1052 		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1053 	} else {
1054 		cfg.src_addr = port_addr;
1055 		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1056 	}
1057 
1058 	ret = dmaengine_slave_config(chan, &cfg);
1059 	if (ret) {
1060 		dev_warn(dev, "dmaengine_slave_config failed %d\n", ret);
1061 		dma_release_channel(chan);
1062 		return NULL;
1063 	}
1064 
1065 	return chan;
1066 }
1067 
1068 static int rspi_request_dma(struct device *dev, struct spi_controller *ctlr,
1069 			    const struct resource *res)
1070 {
1071 	const struct rspi_plat_data *rspi_pd = dev_get_platdata(dev);
1072 	unsigned int dma_tx_id, dma_rx_id;
1073 
1074 	if (dev->of_node) {
1075 		/* In the OF case we will get the slave IDs from the DT */
1076 		dma_tx_id = 0;
1077 		dma_rx_id = 0;
1078 	} else if (rspi_pd && rspi_pd->dma_tx_id && rspi_pd->dma_rx_id) {
1079 		dma_tx_id = rspi_pd->dma_tx_id;
1080 		dma_rx_id = rspi_pd->dma_rx_id;
1081 	} else {
1082 		/* The driver assumes no error. */
1083 		return 0;
1084 	}
1085 
1086 	ctlr->dma_tx = rspi_request_dma_chan(dev, DMA_MEM_TO_DEV, dma_tx_id,
1087 					     res->start + RSPI_SPDR);
1088 	if (!ctlr->dma_tx)
1089 		return -ENODEV;
1090 
1091 	ctlr->dma_rx = rspi_request_dma_chan(dev, DMA_DEV_TO_MEM, dma_rx_id,
1092 					     res->start + RSPI_SPDR);
1093 	if (!ctlr->dma_rx) {
1094 		dma_release_channel(ctlr->dma_tx);
1095 		ctlr->dma_tx = NULL;
1096 		return -ENODEV;
1097 	}
1098 
1099 	ctlr->can_dma = rspi_can_dma;
1100 	dev_info(dev, "DMA available");
1101 	return 0;
1102 }
1103 
1104 static void rspi_release_dma(struct spi_controller *ctlr)
1105 {
1106 	if (ctlr->dma_tx)
1107 		dma_release_channel(ctlr->dma_tx);
1108 	if (ctlr->dma_rx)
1109 		dma_release_channel(ctlr->dma_rx);
1110 }
1111 
1112 static int rspi_remove(struct platform_device *pdev)
1113 {
1114 	struct rspi_data *rspi = platform_get_drvdata(pdev);
1115 
1116 	rspi_release_dma(rspi->ctlr);
1117 	pm_runtime_disable(&pdev->dev);
1118 
1119 	return 0;
1120 }
1121 
1122 static const struct spi_ops rspi_ops = {
1123 	.set_config_register =	rspi_set_config_register,
1124 	.transfer_one =		rspi_transfer_one,
1125 	.mode_bits =		SPI_CPHA | SPI_CPOL | SPI_LOOP,
1126 	.flags =		SPI_CONTROLLER_MUST_TX,
1127 	.fifo_size =		8,
1128 	.num_hw_ss =		2,
1129 };
1130 
1131 static const struct spi_ops rspi_rz_ops = {
1132 	.set_config_register =	rspi_rz_set_config_register,
1133 	.transfer_one =		rspi_rz_transfer_one,
1134 	.mode_bits =		SPI_CPHA | SPI_CPOL | SPI_LOOP,
1135 	.flags =		SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX,
1136 	.fifo_size =		8,	/* 8 for TX, 32 for RX */
1137 	.num_hw_ss =		1,
1138 };
1139 
1140 static const struct spi_ops qspi_ops = {
1141 	.set_config_register =	qspi_set_config_register,
1142 	.transfer_one =		qspi_transfer_one,
1143 	.mode_bits =		SPI_CPHA | SPI_CPOL | SPI_LOOP |
1144 				SPI_TX_DUAL | SPI_TX_QUAD |
1145 				SPI_RX_DUAL | SPI_RX_QUAD,
1146 	.flags =		SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX,
1147 	.fifo_size =		32,
1148 	.num_hw_ss =		1,
1149 };
1150 
1151 #ifdef CONFIG_OF
1152 static const struct of_device_id rspi_of_match[] = {
1153 	/* RSPI on legacy SH */
1154 	{ .compatible = "renesas,rspi", .data = &rspi_ops },
1155 	/* RSPI on RZ/A1H */
1156 	{ .compatible = "renesas,rspi-rz", .data = &rspi_rz_ops },
1157 	/* QSPI on R-Car Gen2 */
1158 	{ .compatible = "renesas,qspi", .data = &qspi_ops },
1159 	{ /* sentinel */ }
1160 };
1161 
1162 MODULE_DEVICE_TABLE(of, rspi_of_match);
1163 
1164 static int rspi_parse_dt(struct device *dev, struct spi_controller *ctlr)
1165 {
1166 	u32 num_cs;
1167 	int error;
1168 
1169 	/* Parse DT properties */
1170 	error = of_property_read_u32(dev->of_node, "num-cs", &num_cs);
1171 	if (error) {
1172 		dev_err(dev, "of_property_read_u32 num-cs failed %d\n", error);
1173 		return error;
1174 	}
1175 
1176 	ctlr->num_chipselect = num_cs;
1177 	return 0;
1178 }
1179 #else
1180 #define rspi_of_match	NULL
1181 static inline int rspi_parse_dt(struct device *dev, struct spi_controller *ctlr)
1182 {
1183 	return -EINVAL;
1184 }
1185 #endif /* CONFIG_OF */
1186 
1187 static int rspi_request_irq(struct device *dev, unsigned int irq,
1188 			    irq_handler_t handler, const char *suffix,
1189 			    void *dev_id)
1190 {
1191 	const char *name = devm_kasprintf(dev, GFP_KERNEL, "%s:%s",
1192 					  dev_name(dev), suffix);
1193 	if (!name)
1194 		return -ENOMEM;
1195 
1196 	return devm_request_irq(dev, irq, handler, 0, name, dev_id);
1197 }
1198 
1199 static int rspi_probe(struct platform_device *pdev)
1200 {
1201 	struct resource *res;
1202 	struct spi_controller *ctlr;
1203 	struct rspi_data *rspi;
1204 	int ret;
1205 	const struct rspi_plat_data *rspi_pd;
1206 	const struct spi_ops *ops;
1207 
1208 	ctlr = spi_alloc_master(&pdev->dev, sizeof(struct rspi_data));
1209 	if (ctlr == NULL)
1210 		return -ENOMEM;
1211 
1212 	ops = of_device_get_match_data(&pdev->dev);
1213 	if (ops) {
1214 		ret = rspi_parse_dt(&pdev->dev, ctlr);
1215 		if (ret)
1216 			goto error1;
1217 	} else {
1218 		ops = (struct spi_ops *)pdev->id_entry->driver_data;
1219 		rspi_pd = dev_get_platdata(&pdev->dev);
1220 		if (rspi_pd && rspi_pd->num_chipselect)
1221 			ctlr->num_chipselect = rspi_pd->num_chipselect;
1222 		else
1223 			ctlr->num_chipselect = 2; /* default */
1224 	}
1225 
1226 	/* ops parameter check */
1227 	if (!ops->set_config_register) {
1228 		dev_err(&pdev->dev, "there is no set_config_register\n");
1229 		ret = -ENODEV;
1230 		goto error1;
1231 	}
1232 
1233 	rspi = spi_controller_get_devdata(ctlr);
1234 	platform_set_drvdata(pdev, rspi);
1235 	rspi->ops = ops;
1236 	rspi->ctlr = ctlr;
1237 
1238 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1239 	rspi->addr = devm_ioremap_resource(&pdev->dev, res);
1240 	if (IS_ERR(rspi->addr)) {
1241 		ret = PTR_ERR(rspi->addr);
1242 		goto error1;
1243 	}
1244 
1245 	rspi->clk = devm_clk_get(&pdev->dev, NULL);
1246 	if (IS_ERR(rspi->clk)) {
1247 		dev_err(&pdev->dev, "cannot get clock\n");
1248 		ret = PTR_ERR(rspi->clk);
1249 		goto error1;
1250 	}
1251 
1252 	pm_runtime_enable(&pdev->dev);
1253 
1254 	init_waitqueue_head(&rspi->wait);
1255 
1256 	ctlr->bus_num = pdev->id;
1257 	ctlr->auto_runtime_pm = true;
1258 	ctlr->transfer_one = ops->transfer_one;
1259 	ctlr->prepare_message = rspi_prepare_message;
1260 	ctlr->unprepare_message = rspi_unprepare_message;
1261 	ctlr->mode_bits = ops->mode_bits;
1262 	ctlr->flags = ops->flags;
1263 	ctlr->dev.of_node = pdev->dev.of_node;
1264 	ctlr->use_gpio_descriptors = true;
1265 	ctlr->max_native_cs = rspi->ops->num_hw_ss;
1266 
1267 	ret = platform_get_irq_byname_optional(pdev, "rx");
1268 	if (ret < 0) {
1269 		ret = platform_get_irq_byname_optional(pdev, "mux");
1270 		if (ret < 0)
1271 			ret = platform_get_irq(pdev, 0);
1272 		if (ret >= 0)
1273 			rspi->rx_irq = rspi->tx_irq = ret;
1274 	} else {
1275 		rspi->rx_irq = ret;
1276 		ret = platform_get_irq_byname(pdev, "tx");
1277 		if (ret >= 0)
1278 			rspi->tx_irq = ret;
1279 	}
1280 
1281 	if (rspi->rx_irq == rspi->tx_irq) {
1282 		/* Single multiplexed interrupt */
1283 		ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_mux,
1284 				       "mux", rspi);
1285 	} else {
1286 		/* Multi-interrupt mode, only SPRI and SPTI are used */
1287 		ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_rx,
1288 				       "rx", rspi);
1289 		if (!ret)
1290 			ret = rspi_request_irq(&pdev->dev, rspi->tx_irq,
1291 					       rspi_irq_tx, "tx", rspi);
1292 	}
1293 	if (ret < 0) {
1294 		dev_err(&pdev->dev, "request_irq error\n");
1295 		goto error2;
1296 	}
1297 
1298 	ret = rspi_request_dma(&pdev->dev, ctlr, res);
1299 	if (ret < 0)
1300 		dev_warn(&pdev->dev, "DMA not available, using PIO\n");
1301 
1302 	ret = devm_spi_register_controller(&pdev->dev, ctlr);
1303 	if (ret < 0) {
1304 		dev_err(&pdev->dev, "devm_spi_register_controller error.\n");
1305 		goto error3;
1306 	}
1307 
1308 	dev_info(&pdev->dev, "probed\n");
1309 
1310 	return 0;
1311 
1312 error3:
1313 	rspi_release_dma(ctlr);
1314 error2:
1315 	pm_runtime_disable(&pdev->dev);
1316 error1:
1317 	spi_controller_put(ctlr);
1318 
1319 	return ret;
1320 }
1321 
1322 static const struct platform_device_id spi_driver_ids[] = {
1323 	{ "rspi",	(kernel_ulong_t)&rspi_ops },
1324 	{},
1325 };
1326 
1327 MODULE_DEVICE_TABLE(platform, spi_driver_ids);
1328 
1329 #ifdef CONFIG_PM_SLEEP
1330 static int rspi_suspend(struct device *dev)
1331 {
1332 	struct rspi_data *rspi = dev_get_drvdata(dev);
1333 
1334 	return spi_controller_suspend(rspi->ctlr);
1335 }
1336 
1337 static int rspi_resume(struct device *dev)
1338 {
1339 	struct rspi_data *rspi = dev_get_drvdata(dev);
1340 
1341 	return spi_controller_resume(rspi->ctlr);
1342 }
1343 
1344 static SIMPLE_DEV_PM_OPS(rspi_pm_ops, rspi_suspend, rspi_resume);
1345 #define DEV_PM_OPS	&rspi_pm_ops
1346 #else
1347 #define DEV_PM_OPS	NULL
1348 #endif /* CONFIG_PM_SLEEP */
1349 
1350 static struct platform_driver rspi_driver = {
1351 	.probe =	rspi_probe,
1352 	.remove =	rspi_remove,
1353 	.id_table =	spi_driver_ids,
1354 	.driver		= {
1355 		.name = "renesas_spi",
1356 		.pm = DEV_PM_OPS,
1357 		.of_match_table = of_match_ptr(rspi_of_match),
1358 	},
1359 };
1360 module_platform_driver(rspi_driver);
1361 
1362 MODULE_DESCRIPTION("Renesas RSPI bus driver");
1363 MODULE_LICENSE("GPL v2");
1364 MODULE_AUTHOR("Yoshihiro Shimoda");
1365 MODULE_ALIAS("platform:rspi");
1366