xref: /linux/drivers/spi/spi-rspi.c (revision 962fad301c33dec69324dc2d9320fd84a119a24c)
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 #include <linux/spinlock.h>
28 
29 #define RSPI_SPCR		0x00	/* Control Register */
30 #define RSPI_SSLP		0x01	/* Slave Select Polarity Register */
31 #define RSPI_SPPCR		0x02	/* Pin Control Register */
32 #define RSPI_SPSR		0x03	/* Status Register */
33 #define RSPI_SPDR		0x04	/* Data Register */
34 #define RSPI_SPSCR		0x08	/* Sequence Control Register */
35 #define RSPI_SPSSR		0x09	/* Sequence Status Register */
36 #define RSPI_SPBR		0x0a	/* Bit Rate Register */
37 #define RSPI_SPDCR		0x0b	/* Data Control Register */
38 #define RSPI_SPCKD		0x0c	/* Clock Delay Register */
39 #define RSPI_SSLND		0x0d	/* Slave Select Negation Delay Register */
40 #define RSPI_SPND		0x0e	/* Next-Access Delay Register */
41 #define RSPI_SPCR2		0x0f	/* Control Register 2 (SH only) */
42 #define RSPI_SPCMD0		0x10	/* Command Register 0 */
43 #define RSPI_SPCMD1		0x12	/* Command Register 1 */
44 #define RSPI_SPCMD2		0x14	/* Command Register 2 */
45 #define RSPI_SPCMD3		0x16	/* Command Register 3 */
46 #define RSPI_SPCMD4		0x18	/* Command Register 4 */
47 #define RSPI_SPCMD5		0x1a	/* Command Register 5 */
48 #define RSPI_SPCMD6		0x1c	/* Command Register 6 */
49 #define RSPI_SPCMD7		0x1e	/* Command Register 7 */
50 #define RSPI_SPCMD(i)		(RSPI_SPCMD0 + (i) * 2)
51 #define RSPI_NUM_SPCMD		8
52 #define RSPI_RZ_NUM_SPCMD	4
53 #define QSPI_NUM_SPCMD		4
54 
55 /* RSPI on RZ only */
56 #define RSPI_SPBFCR		0x20	/* Buffer Control Register */
57 #define RSPI_SPBFDR		0x22	/* Buffer Data Count Setting Register */
58 
59 /* QSPI only */
60 #define QSPI_SPBFCR		0x18	/* Buffer Control Register */
61 #define QSPI_SPBDCR		0x1a	/* Buffer Data Count Register */
62 #define QSPI_SPBMUL0		0x1c	/* Transfer Data Length Multiplier Setting Register 0 */
63 #define QSPI_SPBMUL1		0x20	/* Transfer Data Length Multiplier Setting Register 1 */
64 #define QSPI_SPBMUL2		0x24	/* Transfer Data Length Multiplier Setting Register 2 */
65 #define QSPI_SPBMUL3		0x28	/* Transfer Data Length Multiplier Setting Register 3 */
66 #define QSPI_SPBMUL(i)		(QSPI_SPBMUL0 + (i) * 4)
67 
68 /* SPCR - Control Register */
69 #define SPCR_SPRIE		0x80	/* Receive Interrupt Enable */
70 #define SPCR_SPE		0x40	/* Function Enable */
71 #define SPCR_SPTIE		0x20	/* Transmit Interrupt Enable */
72 #define SPCR_SPEIE		0x10	/* Error Interrupt Enable */
73 #define SPCR_MSTR		0x08	/* Master/Slave Mode Select */
74 #define SPCR_MODFEN		0x04	/* Mode Fault Error Detection Enable */
75 /* RSPI on SH only */
76 #define SPCR_TXMD		0x02	/* TX Only Mode (vs. Full Duplex) */
77 #define SPCR_SPMS		0x01	/* 3-wire Mode (vs. 4-wire) */
78 /* QSPI on R-Car Gen2 only */
79 #define SPCR_WSWAP		0x02	/* Word Swap of read-data for DMAC */
80 #define SPCR_BSWAP		0x01	/* Byte Swap of read-data for DMAC */
81 
82 /* SSLP - Slave Select Polarity Register */
83 #define SSLP_SSLP(i)		BIT(i)	/* SSLi 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 speed_hz;
183 	struct spi_controller *ctlr;
184 	struct platform_device *pdev;
185 	wait_queue_head_t wait;
186 	spinlock_t lock;		/* Protects RMW-access to RSPI_SSLP */
187 	struct clk *clk;
188 	u16 spcmd;
189 	u8 spsr;
190 	u8 sppcr;
191 	int rx_irq, tx_irq;
192 	const struct spi_ops *ops;
193 
194 	unsigned dma_callbacked:1;
195 	unsigned byte_access:1;
196 };
197 
198 static void rspi_write8(const struct rspi_data *rspi, u8 data, u16 offset)
199 {
200 	iowrite8(data, rspi->addr + offset);
201 }
202 
203 static void rspi_write16(const struct rspi_data *rspi, u16 data, u16 offset)
204 {
205 	iowrite16(data, rspi->addr + offset);
206 }
207 
208 static void rspi_write32(const struct rspi_data *rspi, u32 data, u16 offset)
209 {
210 	iowrite32(data, rspi->addr + offset);
211 }
212 
213 static u8 rspi_read8(const struct rspi_data *rspi, u16 offset)
214 {
215 	return ioread8(rspi->addr + offset);
216 }
217 
218 static u16 rspi_read16(const struct rspi_data *rspi, u16 offset)
219 {
220 	return ioread16(rspi->addr + offset);
221 }
222 
223 static void rspi_write_data(const struct rspi_data *rspi, u16 data)
224 {
225 	if (rspi->byte_access)
226 		rspi_write8(rspi, data, RSPI_SPDR);
227 	else /* 16 bit */
228 		rspi_write16(rspi, data, RSPI_SPDR);
229 }
230 
231 static u16 rspi_read_data(const struct rspi_data *rspi)
232 {
233 	if (rspi->byte_access)
234 		return rspi_read8(rspi, RSPI_SPDR);
235 	else /* 16 bit */
236 		return rspi_read16(rspi, RSPI_SPDR);
237 }
238 
239 /* optional functions */
240 struct spi_ops {
241 	int (*set_config_register)(struct rspi_data *rspi, int access_size);
242 	int (*transfer_one)(struct spi_controller *ctlr,
243 			    struct spi_device *spi, struct spi_transfer *xfer);
244 	u16 extra_mode_bits;
245 	u16 flags;
246 	u16 fifo_size;
247 	u8 num_hw_ss;
248 };
249 
250 /*
251  * functions for RSPI on legacy SH
252  */
253 static int rspi_set_config_register(struct rspi_data *rspi, int access_size)
254 {
255 	int spbr;
256 
257 	/* Sets output mode, MOSI signal, and (optionally) loopback */
258 	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
259 
260 	/* Sets transfer bit rate */
261 	spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk), 2 * rspi->speed_hz) - 1;
262 	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
263 
264 	/* Disable dummy transmission, set 16-bit word access, 1 frame */
265 	rspi_write8(rspi, 0, RSPI_SPDCR);
266 	rspi->byte_access = 0;
267 
268 	/* Sets RSPCK, SSL, next-access delay value */
269 	rspi_write8(rspi, 0x00, RSPI_SPCKD);
270 	rspi_write8(rspi, 0x00, RSPI_SSLND);
271 	rspi_write8(rspi, 0x00, RSPI_SPND);
272 
273 	/* Sets parity, interrupt mask */
274 	rspi_write8(rspi, 0x00, RSPI_SPCR2);
275 
276 	/* Resets sequencer */
277 	rspi_write8(rspi, 0, RSPI_SPSCR);
278 	rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size);
279 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
280 
281 	/* Sets RSPI mode */
282 	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
283 
284 	return 0;
285 }
286 
287 /*
288  * functions for RSPI on RZ
289  */
290 static int rspi_rz_set_config_register(struct rspi_data *rspi, int access_size)
291 {
292 	int spbr;
293 	int div = 0;
294 	unsigned long clksrc;
295 
296 	/* Sets output mode, MOSI signal, and (optionally) loopback */
297 	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
298 
299 	clksrc = clk_get_rate(rspi->clk);
300 	while (div < 3) {
301 		if (rspi->speed_hz >= clksrc/4) /* 4=(CLK/2)/2 */
302 			break;
303 		div++;
304 		clksrc /= 2;
305 	}
306 
307 	/* Sets transfer bit rate */
308 	spbr = DIV_ROUND_UP(clksrc, 2 * rspi->speed_hz) - 1;
309 	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
310 	rspi->spcmd |= div << 2;
311 
312 	/* Disable dummy transmission, set byte access */
313 	rspi_write8(rspi, SPDCR_SPLBYTE, RSPI_SPDCR);
314 	rspi->byte_access = 1;
315 
316 	/* Sets RSPCK, SSL, next-access delay value */
317 	rspi_write8(rspi, 0x00, RSPI_SPCKD);
318 	rspi_write8(rspi, 0x00, RSPI_SSLND);
319 	rspi_write8(rspi, 0x00, RSPI_SPND);
320 
321 	/* Resets sequencer */
322 	rspi_write8(rspi, 0, RSPI_SPSCR);
323 	rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size);
324 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
325 
326 	/* Sets RSPI mode */
327 	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
328 
329 	return 0;
330 }
331 
332 /*
333  * functions for QSPI
334  */
335 static int qspi_set_config_register(struct rspi_data *rspi, int access_size)
336 {
337 	int spbr;
338 
339 	/* Sets output mode, MOSI signal, and (optionally) loopback */
340 	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
341 
342 	/* Sets transfer bit rate */
343 	spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk), 2 * rspi->speed_hz);
344 	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
345 
346 	/* Disable dummy transmission, set byte access */
347 	rspi_write8(rspi, 0, RSPI_SPDCR);
348 	rspi->byte_access = 1;
349 
350 	/* Sets RSPCK, SSL, next-access delay value */
351 	rspi_write8(rspi, 0x00, RSPI_SPCKD);
352 	rspi_write8(rspi, 0x00, RSPI_SSLND);
353 	rspi_write8(rspi, 0x00, RSPI_SPND);
354 
355 	/* Data Length Setting */
356 	if (access_size == 8)
357 		rspi->spcmd |= SPCMD_SPB_8BIT;
358 	else if (access_size == 16)
359 		rspi->spcmd |= SPCMD_SPB_16BIT;
360 	else
361 		rspi->spcmd |= SPCMD_SPB_32BIT;
362 
363 	rspi->spcmd |= SPCMD_SCKDEN | SPCMD_SLNDEN | SPCMD_SPNDEN;
364 
365 	/* Resets transfer data length */
366 	rspi_write32(rspi, 0, QSPI_SPBMUL0);
367 
368 	/* Resets transmit and receive buffer */
369 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
370 	/* Sets buffer to allow normal operation */
371 	rspi_write8(rspi, 0x00, QSPI_SPBFCR);
372 
373 	/* Resets sequencer */
374 	rspi_write8(rspi, 0, RSPI_SPSCR);
375 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
376 
377 	/* Sets RSPI mode */
378 	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
379 
380 	return 0;
381 }
382 
383 static void qspi_update(const struct rspi_data *rspi, u8 mask, u8 val, u8 reg)
384 {
385 	u8 data;
386 
387 	data = rspi_read8(rspi, reg);
388 	data &= ~mask;
389 	data |= (val & mask);
390 	rspi_write8(rspi, data, reg);
391 }
392 
393 static unsigned int qspi_set_send_trigger(struct rspi_data *rspi,
394 					  unsigned int len)
395 {
396 	unsigned int n;
397 
398 	n = min(len, QSPI_BUFFER_SIZE);
399 
400 	if (len >= QSPI_BUFFER_SIZE) {
401 		/* sets triggering number to 32 bytes */
402 		qspi_update(rspi, SPBFCR_TXTRG_MASK,
403 			     SPBFCR_TXTRG_32B, QSPI_SPBFCR);
404 	} else {
405 		/* sets triggering number to 1 byte */
406 		qspi_update(rspi, SPBFCR_TXTRG_MASK,
407 			     SPBFCR_TXTRG_1B, QSPI_SPBFCR);
408 	}
409 
410 	return n;
411 }
412 
413 static int qspi_set_receive_trigger(struct rspi_data *rspi, unsigned int len)
414 {
415 	unsigned int n;
416 
417 	n = min(len, QSPI_BUFFER_SIZE);
418 
419 	if (len >= QSPI_BUFFER_SIZE) {
420 		/* sets triggering number to 32 bytes */
421 		qspi_update(rspi, SPBFCR_RXTRG_MASK,
422 			     SPBFCR_RXTRG_32B, QSPI_SPBFCR);
423 	} else {
424 		/* sets triggering number to 1 byte */
425 		qspi_update(rspi, SPBFCR_RXTRG_MASK,
426 			     SPBFCR_RXTRG_1B, QSPI_SPBFCR);
427 	}
428 	return n;
429 }
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 		dev_warn_once(&rspi->ctlr->dev,
624 			      "DMA not available, falling back to PIO\n");
625 	}
626 	return ret;
627 }
628 
629 static void rspi_receive_init(const struct rspi_data *rspi)
630 {
631 	u8 spsr;
632 
633 	spsr = rspi_read8(rspi, RSPI_SPSR);
634 	if (spsr & SPSR_SPRF)
635 		rspi_read_data(rspi);	/* dummy read */
636 	if (spsr & SPSR_OVRF)
637 		rspi_write8(rspi, rspi_read8(rspi, RSPI_SPSR) & ~SPSR_OVRF,
638 			    RSPI_SPSR);
639 }
640 
641 static void rspi_rz_receive_init(const struct rspi_data *rspi)
642 {
643 	rspi_receive_init(rspi);
644 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, RSPI_SPBFCR);
645 	rspi_write8(rspi, 0, RSPI_SPBFCR);
646 }
647 
648 static void qspi_receive_init(const struct rspi_data *rspi)
649 {
650 	u8 spsr;
651 
652 	spsr = rspi_read8(rspi, RSPI_SPSR);
653 	if (spsr & SPSR_SPRF)
654 		rspi_read_data(rspi);   /* dummy read */
655 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
656 	rspi_write8(rspi, 0, QSPI_SPBFCR);
657 }
658 
659 static bool __rspi_can_dma(const struct rspi_data *rspi,
660 			   const struct spi_transfer *xfer)
661 {
662 	return xfer->len > rspi->ops->fifo_size;
663 }
664 
665 static bool rspi_can_dma(struct spi_controller *ctlr, struct spi_device *spi,
666 			 struct spi_transfer *xfer)
667 {
668 	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
669 
670 	return __rspi_can_dma(rspi, xfer);
671 }
672 
673 static int rspi_dma_check_then_transfer(struct rspi_data *rspi,
674 					 struct spi_transfer *xfer)
675 {
676 	if (!rspi->ctlr->can_dma || !__rspi_can_dma(rspi, xfer))
677 		return -EAGAIN;
678 
679 	/* rx_buf can be NULL on RSPI on SH in TX-only Mode */
680 	return rspi_dma_transfer(rspi, &xfer->tx_sg,
681 				xfer->rx_buf ? &xfer->rx_sg : NULL);
682 }
683 
684 static int rspi_common_transfer(struct rspi_data *rspi,
685 				struct spi_transfer *xfer)
686 {
687 	int ret;
688 
689 	ret = rspi_dma_check_then_transfer(rspi, xfer);
690 	if (ret != -EAGAIN)
691 		return ret;
692 
693 	ret = rspi_pio_transfer(rspi, xfer->tx_buf, xfer->rx_buf, xfer->len);
694 	if (ret < 0)
695 		return ret;
696 
697 	/* Wait for the last transmission */
698 	rspi_wait_for_tx_empty(rspi);
699 
700 	return 0;
701 }
702 
703 static int rspi_transfer_one(struct spi_controller *ctlr,
704 			     struct spi_device *spi, struct spi_transfer *xfer)
705 {
706 	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
707 	u8 spcr;
708 
709 	spcr = rspi_read8(rspi, RSPI_SPCR);
710 	if (xfer->rx_buf) {
711 		rspi_receive_init(rspi);
712 		spcr &= ~SPCR_TXMD;
713 	} else {
714 		spcr |= SPCR_TXMD;
715 	}
716 	rspi_write8(rspi, spcr, RSPI_SPCR);
717 
718 	return rspi_common_transfer(rspi, xfer);
719 }
720 
721 static int rspi_rz_transfer_one(struct spi_controller *ctlr,
722 				struct spi_device *spi,
723 				struct spi_transfer *xfer)
724 {
725 	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
726 
727 	rspi_rz_receive_init(rspi);
728 
729 	return rspi_common_transfer(rspi, xfer);
730 }
731 
732 static int qspi_trigger_transfer_out_in(struct rspi_data *rspi, const u8 *tx,
733 					u8 *rx, unsigned int len)
734 {
735 	unsigned int i, n;
736 	int ret;
737 
738 	while (len > 0) {
739 		n = qspi_set_send_trigger(rspi, len);
740 		qspi_set_receive_trigger(rspi, len);
741 		ret = rspi_wait_for_tx_empty(rspi);
742 		if (ret < 0) {
743 			dev_err(&rspi->ctlr->dev, "transmit timeout\n");
744 			return ret;
745 		}
746 		for (i = 0; i < n; i++)
747 			rspi_write_data(rspi, *tx++);
748 
749 		ret = rspi_wait_for_rx_full(rspi);
750 		if (ret < 0) {
751 			dev_err(&rspi->ctlr->dev, "receive timeout\n");
752 			return ret;
753 		}
754 		for (i = 0; i < n; i++)
755 			*rx++ = rspi_read_data(rspi);
756 
757 		len -= n;
758 	}
759 
760 	return 0;
761 }
762 
763 static int qspi_transfer_out_in(struct rspi_data *rspi,
764 				struct spi_transfer *xfer)
765 {
766 	int ret;
767 
768 	qspi_receive_init(rspi);
769 
770 	ret = rspi_dma_check_then_transfer(rspi, xfer);
771 	if (ret != -EAGAIN)
772 		return ret;
773 
774 	return qspi_trigger_transfer_out_in(rspi, xfer->tx_buf,
775 					    xfer->rx_buf, xfer->len);
776 }
777 
778 static int qspi_transfer_out(struct rspi_data *rspi, struct spi_transfer *xfer)
779 {
780 	const u8 *tx = xfer->tx_buf;
781 	unsigned int n = xfer->len;
782 	unsigned int i, len;
783 	int ret;
784 
785 	if (rspi->ctlr->can_dma && __rspi_can_dma(rspi, xfer)) {
786 		ret = rspi_dma_transfer(rspi, &xfer->tx_sg, NULL);
787 		if (ret != -EAGAIN)
788 			return ret;
789 	}
790 
791 	while (n > 0) {
792 		len = qspi_set_send_trigger(rspi, n);
793 		ret = rspi_wait_for_tx_empty(rspi);
794 		if (ret < 0) {
795 			dev_err(&rspi->ctlr->dev, "transmit timeout\n");
796 			return ret;
797 		}
798 		for (i = 0; i < len; i++)
799 			rspi_write_data(rspi, *tx++);
800 
801 		n -= len;
802 	}
803 
804 	/* Wait for the last transmission */
805 	rspi_wait_for_tx_empty(rspi);
806 
807 	return 0;
808 }
809 
810 static int qspi_transfer_in(struct rspi_data *rspi, struct spi_transfer *xfer)
811 {
812 	u8 *rx = xfer->rx_buf;
813 	unsigned int n = xfer->len;
814 	unsigned int i, len;
815 	int ret;
816 
817 	if (rspi->ctlr->can_dma && __rspi_can_dma(rspi, xfer)) {
818 		int ret = rspi_dma_transfer(rspi, NULL, &xfer->rx_sg);
819 		if (ret != -EAGAIN)
820 			return ret;
821 	}
822 
823 	while (n > 0) {
824 		len = qspi_set_receive_trigger(rspi, n);
825 		ret = rspi_wait_for_rx_full(rspi);
826 		if (ret < 0) {
827 			dev_err(&rspi->ctlr->dev, "receive timeout\n");
828 			return ret;
829 		}
830 		for (i = 0; i < len; i++)
831 			*rx++ = rspi_read_data(rspi);
832 
833 		n -= len;
834 	}
835 
836 	return 0;
837 }
838 
839 static int qspi_transfer_one(struct spi_controller *ctlr,
840 			     struct spi_device *spi, struct spi_transfer *xfer)
841 {
842 	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
843 
844 	if (spi->mode & SPI_LOOP) {
845 		return qspi_transfer_out_in(rspi, xfer);
846 	} else if (xfer->tx_nbits > SPI_NBITS_SINGLE) {
847 		/* Quad or Dual SPI Write */
848 		return qspi_transfer_out(rspi, xfer);
849 	} else if (xfer->rx_nbits > SPI_NBITS_SINGLE) {
850 		/* Quad or Dual SPI Read */
851 		return qspi_transfer_in(rspi, xfer);
852 	} else {
853 		/* Single SPI Transfer */
854 		return qspi_transfer_out_in(rspi, xfer);
855 	}
856 }
857 
858 static u16 qspi_transfer_mode(const struct spi_transfer *xfer)
859 {
860 	if (xfer->tx_buf)
861 		switch (xfer->tx_nbits) {
862 		case SPI_NBITS_QUAD:
863 			return SPCMD_SPIMOD_QUAD;
864 		case SPI_NBITS_DUAL:
865 			return SPCMD_SPIMOD_DUAL;
866 		default:
867 			return 0;
868 		}
869 	if (xfer->rx_buf)
870 		switch (xfer->rx_nbits) {
871 		case SPI_NBITS_QUAD:
872 			return SPCMD_SPIMOD_QUAD | SPCMD_SPRW;
873 		case SPI_NBITS_DUAL:
874 			return SPCMD_SPIMOD_DUAL | SPCMD_SPRW;
875 		default:
876 			return 0;
877 		}
878 
879 	return 0;
880 }
881 
882 static int qspi_setup_sequencer(struct rspi_data *rspi,
883 				const struct spi_message *msg)
884 {
885 	const struct spi_transfer *xfer;
886 	unsigned int i = 0, len = 0;
887 	u16 current_mode = 0xffff, mode;
888 
889 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
890 		mode = qspi_transfer_mode(xfer);
891 		if (mode == current_mode) {
892 			len += xfer->len;
893 			continue;
894 		}
895 
896 		/* Transfer mode change */
897 		if (i) {
898 			/* Set transfer data length of previous transfer */
899 			rspi_write32(rspi, len, QSPI_SPBMUL(i - 1));
900 		}
901 
902 		if (i >= QSPI_NUM_SPCMD) {
903 			dev_err(&msg->spi->dev,
904 				"Too many different transfer modes");
905 			return -EINVAL;
906 		}
907 
908 		/* Program transfer mode for this transfer */
909 		rspi_write16(rspi, rspi->spcmd | mode, RSPI_SPCMD(i));
910 		current_mode = mode;
911 		len = xfer->len;
912 		i++;
913 	}
914 	if (i) {
915 		/* Set final transfer data length and sequence length */
916 		rspi_write32(rspi, len, QSPI_SPBMUL(i - 1));
917 		rspi_write8(rspi, i - 1, RSPI_SPSCR);
918 	}
919 
920 	return 0;
921 }
922 
923 static int rspi_setup(struct spi_device *spi)
924 {
925 	struct rspi_data *rspi = spi_controller_get_devdata(spi->controller);
926 	u8 sslp;
927 
928 	if (spi->cs_gpiod)
929 		return 0;
930 
931 	pm_runtime_get_sync(&rspi->pdev->dev);
932 	spin_lock_irq(&rspi->lock);
933 
934 	sslp = rspi_read8(rspi, RSPI_SSLP);
935 	if (spi->mode & SPI_CS_HIGH)
936 		sslp |= SSLP_SSLP(spi->chip_select);
937 	else
938 		sslp &= ~SSLP_SSLP(spi->chip_select);
939 	rspi_write8(rspi, sslp, RSPI_SSLP);
940 
941 	spin_unlock_irq(&rspi->lock);
942 	pm_runtime_put(&rspi->pdev->dev);
943 	return 0;
944 }
945 
946 static int rspi_prepare_message(struct spi_controller *ctlr,
947 				struct spi_message *msg)
948 {
949 	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
950 	struct spi_device *spi = msg->spi;
951 	const struct spi_transfer *xfer;
952 	int ret;
953 
954 	/*
955 	 * As the Bit Rate Register must not be changed while the device is
956 	 * active, all transfers in a message must use the same bit rate.
957 	 * In theory, the sequencer could be enabled, and each Command Register
958 	 * could divide the base bit rate by a different value.
959 	 * However, most RSPI variants do not have Transfer Data Length
960 	 * Multiplier Setting Registers, so each sequence step would be limited
961 	 * to a single word, making this feature unsuitable for large
962 	 * transfers, which would gain most from it.
963 	 */
964 	rspi->speed_hz = spi->max_speed_hz;
965 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
966 		if (xfer->speed_hz < rspi->speed_hz)
967 			rspi->speed_hz = xfer->speed_hz;
968 	}
969 
970 	rspi->spcmd = SPCMD_SSLKP;
971 	if (spi->mode & SPI_CPOL)
972 		rspi->spcmd |= SPCMD_CPOL;
973 	if (spi->mode & SPI_CPHA)
974 		rspi->spcmd |= SPCMD_CPHA;
975 	if (spi->mode & SPI_LSB_FIRST)
976 		rspi->spcmd |= SPCMD_LSBF;
977 
978 	/* Configure slave signal to assert */
979 	rspi->spcmd |= SPCMD_SSLA(spi->cs_gpiod ? rspi->ctlr->unused_native_cs
980 						: spi->chip_select);
981 
982 	/* CMOS output mode and MOSI signal from previous transfer */
983 	rspi->sppcr = 0;
984 	if (spi->mode & SPI_LOOP)
985 		rspi->sppcr |= SPPCR_SPLP;
986 
987 	rspi->ops->set_config_register(rspi, 8);
988 
989 	if (msg->spi->mode &
990 	    (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD)) {
991 		/* Setup sequencer for messages with multiple transfer modes */
992 		ret = qspi_setup_sequencer(rspi, msg);
993 		if (ret < 0)
994 			return ret;
995 	}
996 
997 	/* Enable SPI function in master mode */
998 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_SPE, RSPI_SPCR);
999 	return 0;
1000 }
1001 
1002 static int rspi_unprepare_message(struct spi_controller *ctlr,
1003 				  struct spi_message *msg)
1004 {
1005 	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
1006 
1007 	/* Disable SPI function */
1008 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_SPE, RSPI_SPCR);
1009 
1010 	/* Reset sequencer for Single SPI Transfers */
1011 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
1012 	rspi_write8(rspi, 0, RSPI_SPSCR);
1013 	return 0;
1014 }
1015 
1016 static irqreturn_t rspi_irq_mux(int irq, void *_sr)
1017 {
1018 	struct rspi_data *rspi = _sr;
1019 	u8 spsr;
1020 	irqreturn_t ret = IRQ_NONE;
1021 	u8 disable_irq = 0;
1022 
1023 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
1024 	if (spsr & SPSR_SPRF)
1025 		disable_irq |= SPCR_SPRIE;
1026 	if (spsr & SPSR_SPTEF)
1027 		disable_irq |= SPCR_SPTIE;
1028 
1029 	if (disable_irq) {
1030 		ret = IRQ_HANDLED;
1031 		rspi_disable_irq(rspi, disable_irq);
1032 		wake_up(&rspi->wait);
1033 	}
1034 
1035 	return ret;
1036 }
1037 
1038 static irqreturn_t rspi_irq_rx(int irq, void *_sr)
1039 {
1040 	struct rspi_data *rspi = _sr;
1041 	u8 spsr;
1042 
1043 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
1044 	if (spsr & SPSR_SPRF) {
1045 		rspi_disable_irq(rspi, SPCR_SPRIE);
1046 		wake_up(&rspi->wait);
1047 		return IRQ_HANDLED;
1048 	}
1049 
1050 	return 0;
1051 }
1052 
1053 static irqreturn_t rspi_irq_tx(int irq, void *_sr)
1054 {
1055 	struct rspi_data *rspi = _sr;
1056 	u8 spsr;
1057 
1058 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
1059 	if (spsr & SPSR_SPTEF) {
1060 		rspi_disable_irq(rspi, SPCR_SPTIE);
1061 		wake_up(&rspi->wait);
1062 		return IRQ_HANDLED;
1063 	}
1064 
1065 	return 0;
1066 }
1067 
1068 static struct dma_chan *rspi_request_dma_chan(struct device *dev,
1069 					      enum dma_transfer_direction dir,
1070 					      unsigned int id,
1071 					      dma_addr_t port_addr)
1072 {
1073 	dma_cap_mask_t mask;
1074 	struct dma_chan *chan;
1075 	struct dma_slave_config cfg;
1076 	int ret;
1077 
1078 	dma_cap_zero(mask);
1079 	dma_cap_set(DMA_SLAVE, mask);
1080 
1081 	chan = dma_request_slave_channel_compat(mask, shdma_chan_filter,
1082 				(void *)(unsigned long)id, dev,
1083 				dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1084 	if (!chan) {
1085 		dev_warn(dev, "dma_request_slave_channel_compat failed\n");
1086 		return NULL;
1087 	}
1088 
1089 	memset(&cfg, 0, sizeof(cfg));
1090 	cfg.direction = dir;
1091 	if (dir == DMA_MEM_TO_DEV) {
1092 		cfg.dst_addr = port_addr;
1093 		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1094 	} else {
1095 		cfg.src_addr = port_addr;
1096 		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1097 	}
1098 
1099 	ret = dmaengine_slave_config(chan, &cfg);
1100 	if (ret) {
1101 		dev_warn(dev, "dmaengine_slave_config failed %d\n", ret);
1102 		dma_release_channel(chan);
1103 		return NULL;
1104 	}
1105 
1106 	return chan;
1107 }
1108 
1109 static int rspi_request_dma(struct device *dev, struct spi_controller *ctlr,
1110 			    const struct resource *res)
1111 {
1112 	const struct rspi_plat_data *rspi_pd = dev_get_platdata(dev);
1113 	unsigned int dma_tx_id, dma_rx_id;
1114 
1115 	if (dev->of_node) {
1116 		/* In the OF case we will get the slave IDs from the DT */
1117 		dma_tx_id = 0;
1118 		dma_rx_id = 0;
1119 	} else if (rspi_pd && rspi_pd->dma_tx_id && rspi_pd->dma_rx_id) {
1120 		dma_tx_id = rspi_pd->dma_tx_id;
1121 		dma_rx_id = rspi_pd->dma_rx_id;
1122 	} else {
1123 		/* The driver assumes no error. */
1124 		return 0;
1125 	}
1126 
1127 	ctlr->dma_tx = rspi_request_dma_chan(dev, DMA_MEM_TO_DEV, dma_tx_id,
1128 					     res->start + RSPI_SPDR);
1129 	if (!ctlr->dma_tx)
1130 		return -ENODEV;
1131 
1132 	ctlr->dma_rx = rspi_request_dma_chan(dev, DMA_DEV_TO_MEM, dma_rx_id,
1133 					     res->start + RSPI_SPDR);
1134 	if (!ctlr->dma_rx) {
1135 		dma_release_channel(ctlr->dma_tx);
1136 		ctlr->dma_tx = NULL;
1137 		return -ENODEV;
1138 	}
1139 
1140 	ctlr->can_dma = rspi_can_dma;
1141 	dev_info(dev, "DMA available");
1142 	return 0;
1143 }
1144 
1145 static void rspi_release_dma(struct spi_controller *ctlr)
1146 {
1147 	if (ctlr->dma_tx)
1148 		dma_release_channel(ctlr->dma_tx);
1149 	if (ctlr->dma_rx)
1150 		dma_release_channel(ctlr->dma_rx);
1151 }
1152 
1153 static int rspi_remove(struct platform_device *pdev)
1154 {
1155 	struct rspi_data *rspi = platform_get_drvdata(pdev);
1156 
1157 	rspi_release_dma(rspi->ctlr);
1158 	pm_runtime_disable(&pdev->dev);
1159 
1160 	return 0;
1161 }
1162 
1163 static const struct spi_ops rspi_ops = {
1164 	.set_config_register =	rspi_set_config_register,
1165 	.transfer_one =		rspi_transfer_one,
1166 	.flags =		SPI_CONTROLLER_MUST_TX,
1167 	.fifo_size =		8,
1168 	.num_hw_ss =		2,
1169 };
1170 
1171 static const struct spi_ops rspi_rz_ops = {
1172 	.set_config_register =	rspi_rz_set_config_register,
1173 	.transfer_one =		rspi_rz_transfer_one,
1174 	.flags =		SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX,
1175 	.fifo_size =		8,	/* 8 for TX, 32 for RX */
1176 	.num_hw_ss =		1,
1177 };
1178 
1179 static const struct spi_ops qspi_ops = {
1180 	.set_config_register =	qspi_set_config_register,
1181 	.transfer_one =		qspi_transfer_one,
1182 	.extra_mode_bits =	SPI_TX_DUAL | SPI_TX_QUAD |
1183 				SPI_RX_DUAL | SPI_RX_QUAD,
1184 	.flags =		SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX,
1185 	.fifo_size =		32,
1186 	.num_hw_ss =		1,
1187 };
1188 
1189 #ifdef CONFIG_OF
1190 static const struct of_device_id rspi_of_match[] = {
1191 	/* RSPI on legacy SH */
1192 	{ .compatible = "renesas,rspi", .data = &rspi_ops },
1193 	/* RSPI on RZ/A1H */
1194 	{ .compatible = "renesas,rspi-rz", .data = &rspi_rz_ops },
1195 	/* QSPI on R-Car Gen2 */
1196 	{ .compatible = "renesas,qspi", .data = &qspi_ops },
1197 	{ /* sentinel */ }
1198 };
1199 
1200 MODULE_DEVICE_TABLE(of, rspi_of_match);
1201 
1202 static int rspi_parse_dt(struct device *dev, struct spi_controller *ctlr)
1203 {
1204 	u32 num_cs;
1205 	int error;
1206 
1207 	/* Parse DT properties */
1208 	error = of_property_read_u32(dev->of_node, "num-cs", &num_cs);
1209 	if (error) {
1210 		dev_err(dev, "of_property_read_u32 num-cs failed %d\n", error);
1211 		return error;
1212 	}
1213 
1214 	ctlr->num_chipselect = num_cs;
1215 	return 0;
1216 }
1217 #else
1218 #define rspi_of_match	NULL
1219 static inline int rspi_parse_dt(struct device *dev, struct spi_controller *ctlr)
1220 {
1221 	return -EINVAL;
1222 }
1223 #endif /* CONFIG_OF */
1224 
1225 static int rspi_request_irq(struct device *dev, unsigned int irq,
1226 			    irq_handler_t handler, const char *suffix,
1227 			    void *dev_id)
1228 {
1229 	const char *name = devm_kasprintf(dev, GFP_KERNEL, "%s:%s",
1230 					  dev_name(dev), suffix);
1231 	if (!name)
1232 		return -ENOMEM;
1233 
1234 	return devm_request_irq(dev, irq, handler, 0, name, dev_id);
1235 }
1236 
1237 static int rspi_probe(struct platform_device *pdev)
1238 {
1239 	struct resource *res;
1240 	struct spi_controller *ctlr;
1241 	struct rspi_data *rspi;
1242 	int ret;
1243 	const struct rspi_plat_data *rspi_pd;
1244 	const struct spi_ops *ops;
1245 
1246 	ctlr = spi_alloc_master(&pdev->dev, sizeof(struct rspi_data));
1247 	if (ctlr == NULL)
1248 		return -ENOMEM;
1249 
1250 	ops = of_device_get_match_data(&pdev->dev);
1251 	if (ops) {
1252 		ret = rspi_parse_dt(&pdev->dev, ctlr);
1253 		if (ret)
1254 			goto error1;
1255 	} else {
1256 		ops = (struct spi_ops *)pdev->id_entry->driver_data;
1257 		rspi_pd = dev_get_platdata(&pdev->dev);
1258 		if (rspi_pd && rspi_pd->num_chipselect)
1259 			ctlr->num_chipselect = rspi_pd->num_chipselect;
1260 		else
1261 			ctlr->num_chipselect = 2; /* default */
1262 	}
1263 
1264 	/* ops parameter check */
1265 	if (!ops->set_config_register) {
1266 		dev_err(&pdev->dev, "there is no set_config_register\n");
1267 		ret = -ENODEV;
1268 		goto error1;
1269 	}
1270 
1271 	rspi = spi_controller_get_devdata(ctlr);
1272 	platform_set_drvdata(pdev, rspi);
1273 	rspi->ops = ops;
1274 	rspi->ctlr = ctlr;
1275 
1276 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1277 	rspi->addr = devm_ioremap_resource(&pdev->dev, res);
1278 	if (IS_ERR(rspi->addr)) {
1279 		ret = PTR_ERR(rspi->addr);
1280 		goto error1;
1281 	}
1282 
1283 	rspi->clk = devm_clk_get(&pdev->dev, NULL);
1284 	if (IS_ERR(rspi->clk)) {
1285 		dev_err(&pdev->dev, "cannot get clock\n");
1286 		ret = PTR_ERR(rspi->clk);
1287 		goto error1;
1288 	}
1289 
1290 	rspi->pdev = pdev;
1291 	pm_runtime_enable(&pdev->dev);
1292 
1293 	init_waitqueue_head(&rspi->wait);
1294 	spin_lock_init(&rspi->lock);
1295 
1296 	ctlr->bus_num = pdev->id;
1297 	ctlr->setup = rspi_setup;
1298 	ctlr->auto_runtime_pm = true;
1299 	ctlr->transfer_one = ops->transfer_one;
1300 	ctlr->prepare_message = rspi_prepare_message;
1301 	ctlr->unprepare_message = rspi_unprepare_message;
1302 	ctlr->mode_bits = SPI_CPHA | SPI_CPOL | SPI_CS_HIGH | SPI_LSB_FIRST |
1303 			  SPI_LOOP | ops->extra_mode_bits;
1304 	ctlr->flags = ops->flags;
1305 	ctlr->dev.of_node = pdev->dev.of_node;
1306 	ctlr->use_gpio_descriptors = true;
1307 	ctlr->max_native_cs = rspi->ops->num_hw_ss;
1308 
1309 	ret = platform_get_irq_byname_optional(pdev, "rx");
1310 	if (ret < 0) {
1311 		ret = platform_get_irq_byname_optional(pdev, "mux");
1312 		if (ret < 0)
1313 			ret = platform_get_irq(pdev, 0);
1314 		if (ret >= 0)
1315 			rspi->rx_irq = rspi->tx_irq = ret;
1316 	} else {
1317 		rspi->rx_irq = ret;
1318 		ret = platform_get_irq_byname(pdev, "tx");
1319 		if (ret >= 0)
1320 			rspi->tx_irq = ret;
1321 	}
1322 
1323 	if (rspi->rx_irq == rspi->tx_irq) {
1324 		/* Single multiplexed interrupt */
1325 		ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_mux,
1326 				       "mux", rspi);
1327 	} else {
1328 		/* Multi-interrupt mode, only SPRI and SPTI are used */
1329 		ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_rx,
1330 				       "rx", rspi);
1331 		if (!ret)
1332 			ret = rspi_request_irq(&pdev->dev, rspi->tx_irq,
1333 					       rspi_irq_tx, "tx", rspi);
1334 	}
1335 	if (ret < 0) {
1336 		dev_err(&pdev->dev, "request_irq error\n");
1337 		goto error2;
1338 	}
1339 
1340 	ret = rspi_request_dma(&pdev->dev, ctlr, res);
1341 	if (ret < 0)
1342 		dev_warn(&pdev->dev, "DMA not available, using PIO\n");
1343 
1344 	ret = devm_spi_register_controller(&pdev->dev, ctlr);
1345 	if (ret < 0) {
1346 		dev_err(&pdev->dev, "devm_spi_register_controller error.\n");
1347 		goto error3;
1348 	}
1349 
1350 	dev_info(&pdev->dev, "probed\n");
1351 
1352 	return 0;
1353 
1354 error3:
1355 	rspi_release_dma(ctlr);
1356 error2:
1357 	pm_runtime_disable(&pdev->dev);
1358 error1:
1359 	spi_controller_put(ctlr);
1360 
1361 	return ret;
1362 }
1363 
1364 static const struct platform_device_id spi_driver_ids[] = {
1365 	{ "rspi",	(kernel_ulong_t)&rspi_ops },
1366 	{},
1367 };
1368 
1369 MODULE_DEVICE_TABLE(platform, spi_driver_ids);
1370 
1371 #ifdef CONFIG_PM_SLEEP
1372 static int rspi_suspend(struct device *dev)
1373 {
1374 	struct rspi_data *rspi = dev_get_drvdata(dev);
1375 
1376 	return spi_controller_suspend(rspi->ctlr);
1377 }
1378 
1379 static int rspi_resume(struct device *dev)
1380 {
1381 	struct rspi_data *rspi = dev_get_drvdata(dev);
1382 
1383 	return spi_controller_resume(rspi->ctlr);
1384 }
1385 
1386 static SIMPLE_DEV_PM_OPS(rspi_pm_ops, rspi_suspend, rspi_resume);
1387 #define DEV_PM_OPS	&rspi_pm_ops
1388 #else
1389 #define DEV_PM_OPS	NULL
1390 #endif /* CONFIG_PM_SLEEP */
1391 
1392 static struct platform_driver rspi_driver = {
1393 	.probe =	rspi_probe,
1394 	.remove =	rspi_remove,
1395 	.id_table =	spi_driver_ids,
1396 	.driver		= {
1397 		.name = "renesas_spi",
1398 		.pm = DEV_PM_OPS,
1399 		.of_match_table = of_match_ptr(rspi_of_match),
1400 	},
1401 };
1402 module_platform_driver(rspi_driver);
1403 
1404 MODULE_DESCRIPTION("Renesas RSPI bus driver");
1405 MODULE_LICENSE("GPL v2");
1406 MODULE_AUTHOR("Yoshihiro Shimoda");
1407 MODULE_ALIAS("platform:rspi");
1408