xref: /openbmc/linux/drivers/spi/spi-rspi.c (revision 6189f1b0)
1 /*
2  * SH RSPI driver
3  *
4  * Copyright (C) 2012, 2013  Renesas Solutions Corp.
5  * Copyright (C) 2014 Glider bvba
6  *
7  * Based on spi-sh.c:
8  * Copyright (C) 2011 Renesas Solutions Corp.
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; version 2 of the License.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  */
19 
20 #include <linux/module.h>
21 #include <linux/kernel.h>
22 #include <linux/sched.h>
23 #include <linux/errno.h>
24 #include <linux/interrupt.h>
25 #include <linux/platform_device.h>
26 #include <linux/io.h>
27 #include <linux/clk.h>
28 #include <linux/dmaengine.h>
29 #include <linux/dma-mapping.h>
30 #include <linux/of_device.h>
31 #include <linux/pm_runtime.h>
32 #include <linux/sh_dma.h>
33 #include <linux/spi/spi.h>
34 #include <linux/spi/rspi.h>
35 
36 #define RSPI_SPCR		0x00	/* Control Register */
37 #define RSPI_SSLP		0x01	/* Slave Select Polarity Register */
38 #define RSPI_SPPCR		0x02	/* Pin Control Register */
39 #define RSPI_SPSR		0x03	/* Status Register */
40 #define RSPI_SPDR		0x04	/* Data Register */
41 #define RSPI_SPSCR		0x08	/* Sequence Control Register */
42 #define RSPI_SPSSR		0x09	/* Sequence Status Register */
43 #define RSPI_SPBR		0x0a	/* Bit Rate Register */
44 #define RSPI_SPDCR		0x0b	/* Data Control Register */
45 #define RSPI_SPCKD		0x0c	/* Clock Delay Register */
46 #define RSPI_SSLND		0x0d	/* Slave Select Negation Delay Register */
47 #define RSPI_SPND		0x0e	/* Next-Access Delay Register */
48 #define RSPI_SPCR2		0x0f	/* Control Register 2 (SH only) */
49 #define RSPI_SPCMD0		0x10	/* Command Register 0 */
50 #define RSPI_SPCMD1		0x12	/* Command Register 1 */
51 #define RSPI_SPCMD2		0x14	/* Command Register 2 */
52 #define RSPI_SPCMD3		0x16	/* Command Register 3 */
53 #define RSPI_SPCMD4		0x18	/* Command Register 4 */
54 #define RSPI_SPCMD5		0x1a	/* Command Register 5 */
55 #define RSPI_SPCMD6		0x1c	/* Command Register 6 */
56 #define RSPI_SPCMD7		0x1e	/* Command Register 7 */
57 #define RSPI_SPCMD(i)		(RSPI_SPCMD0 + (i) * 2)
58 #define RSPI_NUM_SPCMD		8
59 #define RSPI_RZ_NUM_SPCMD	4
60 #define QSPI_NUM_SPCMD		4
61 
62 /* RSPI on RZ only */
63 #define RSPI_SPBFCR		0x20	/* Buffer Control Register */
64 #define RSPI_SPBFDR		0x22	/* Buffer Data Count Setting Register */
65 
66 /* QSPI only */
67 #define QSPI_SPBFCR		0x18	/* Buffer Control Register */
68 #define QSPI_SPBDCR		0x1a	/* Buffer Data Count Register */
69 #define QSPI_SPBMUL0		0x1c	/* Transfer Data Length Multiplier Setting Register 0 */
70 #define QSPI_SPBMUL1		0x20	/* Transfer Data Length Multiplier Setting Register 1 */
71 #define QSPI_SPBMUL2		0x24	/* Transfer Data Length Multiplier Setting Register 2 */
72 #define QSPI_SPBMUL3		0x28	/* Transfer Data Length Multiplier Setting Register 3 */
73 #define QSPI_SPBMUL(i)		(QSPI_SPBMUL0 + (i) * 4)
74 
75 /* SPCR - Control Register */
76 #define SPCR_SPRIE		0x80	/* Receive Interrupt Enable */
77 #define SPCR_SPE		0x40	/* Function Enable */
78 #define SPCR_SPTIE		0x20	/* Transmit Interrupt Enable */
79 #define SPCR_SPEIE		0x10	/* Error Interrupt Enable */
80 #define SPCR_MSTR		0x08	/* Master/Slave Mode Select */
81 #define SPCR_MODFEN		0x04	/* Mode Fault Error Detection Enable */
82 /* RSPI on SH only */
83 #define SPCR_TXMD		0x02	/* TX Only Mode (vs. Full Duplex) */
84 #define SPCR_SPMS		0x01	/* 3-wire Mode (vs. 4-wire) */
85 /* QSPI on R-Car Gen2 only */
86 #define SPCR_WSWAP		0x02	/* Word Swap of read-data for DMAC */
87 #define SPCR_BSWAP		0x01	/* Byte Swap of read-data for DMAC */
88 
89 /* SSLP - Slave Select Polarity Register */
90 #define SSLP_SSL1P		0x02	/* SSL1 Signal Polarity Setting */
91 #define SSLP_SSL0P		0x01	/* SSL0 Signal Polarity Setting */
92 
93 /* SPPCR - Pin Control Register */
94 #define SPPCR_MOIFE		0x20	/* MOSI Idle Value Fixing Enable */
95 #define SPPCR_MOIFV		0x10	/* MOSI Idle Fixed Value */
96 #define SPPCR_SPOM		0x04
97 #define SPPCR_SPLP2		0x02	/* Loopback Mode 2 (non-inverting) */
98 #define SPPCR_SPLP		0x01	/* Loopback Mode (inverting) */
99 
100 #define SPPCR_IO3FV		0x04	/* Single-/Dual-SPI Mode IO3 Output Fixed Value */
101 #define SPPCR_IO2FV		0x04	/* Single-/Dual-SPI Mode IO2 Output Fixed Value */
102 
103 /* SPSR - Status Register */
104 #define SPSR_SPRF		0x80	/* Receive Buffer Full Flag */
105 #define SPSR_TEND		0x40	/* Transmit End */
106 #define SPSR_SPTEF		0x20	/* Transmit Buffer Empty Flag */
107 #define SPSR_PERF		0x08	/* Parity Error Flag */
108 #define SPSR_MODF		0x04	/* Mode Fault Error Flag */
109 #define SPSR_IDLNF		0x02	/* RSPI Idle Flag */
110 #define SPSR_OVRF		0x01	/* Overrun Error Flag (RSPI only) */
111 
112 /* SPSCR - Sequence Control Register */
113 #define SPSCR_SPSLN_MASK	0x07	/* Sequence Length Specification */
114 
115 /* SPSSR - Sequence Status Register */
116 #define SPSSR_SPECM_MASK	0x70	/* Command Error Mask */
117 #define SPSSR_SPCP_MASK		0x07	/* Command Pointer Mask */
118 
119 /* SPDCR - Data Control Register */
120 #define SPDCR_TXDMY		0x80	/* Dummy Data Transmission Enable */
121 #define SPDCR_SPLW1		0x40	/* Access Width Specification (RZ) */
122 #define SPDCR_SPLW0		0x20	/* Access Width Specification (RZ) */
123 #define SPDCR_SPLLWORD		(SPDCR_SPLW1 | SPDCR_SPLW0)
124 #define SPDCR_SPLWORD		SPDCR_SPLW1
125 #define SPDCR_SPLBYTE		SPDCR_SPLW0
126 #define SPDCR_SPLW		0x20	/* Access Width Specification (SH) */
127 #define SPDCR_SPRDTD		0x10	/* Receive Transmit Data Select (SH) */
128 #define SPDCR_SLSEL1		0x08
129 #define SPDCR_SLSEL0		0x04
130 #define SPDCR_SLSEL_MASK	0x0c	/* SSL1 Output Select (SH) */
131 #define SPDCR_SPFC1		0x02
132 #define SPDCR_SPFC0		0x01
133 #define SPDCR_SPFC_MASK		0x03	/* Frame Count Setting (1-4) (SH) */
134 
135 /* SPCKD - Clock Delay Register */
136 #define SPCKD_SCKDL_MASK	0x07	/* Clock Delay Setting (1-8) */
137 
138 /* SSLND - Slave Select Negation Delay Register */
139 #define SSLND_SLNDL_MASK	0x07	/* SSL Negation Delay Setting (1-8) */
140 
141 /* SPND - Next-Access Delay Register */
142 #define SPND_SPNDL_MASK		0x07	/* Next-Access Delay Setting (1-8) */
143 
144 /* SPCR2 - Control Register 2 */
145 #define SPCR2_PTE		0x08	/* Parity Self-Test Enable */
146 #define SPCR2_SPIE		0x04	/* Idle Interrupt Enable */
147 #define SPCR2_SPOE		0x02	/* Odd Parity Enable (vs. Even) */
148 #define SPCR2_SPPE		0x01	/* Parity Enable */
149 
150 /* SPCMDn - Command Registers */
151 #define SPCMD_SCKDEN		0x8000	/* Clock Delay Setting Enable */
152 #define SPCMD_SLNDEN		0x4000	/* SSL Negation Delay Setting Enable */
153 #define SPCMD_SPNDEN		0x2000	/* Next-Access Delay Enable */
154 #define SPCMD_LSBF		0x1000	/* LSB First */
155 #define SPCMD_SPB_MASK		0x0f00	/* Data Length Setting */
156 #define SPCMD_SPB_8_TO_16(bit)	(((bit - 1) << 8) & SPCMD_SPB_MASK)
157 #define SPCMD_SPB_8BIT		0x0000	/* QSPI only */
158 #define SPCMD_SPB_16BIT		0x0100
159 #define SPCMD_SPB_20BIT		0x0000
160 #define SPCMD_SPB_24BIT		0x0100
161 #define SPCMD_SPB_32BIT		0x0200
162 #define SPCMD_SSLKP		0x0080	/* SSL Signal Level Keeping */
163 #define SPCMD_SPIMOD_MASK	0x0060	/* SPI Operating Mode (QSPI only) */
164 #define SPCMD_SPIMOD1		0x0040
165 #define SPCMD_SPIMOD0		0x0020
166 #define SPCMD_SPIMOD_SINGLE	0
167 #define SPCMD_SPIMOD_DUAL	SPCMD_SPIMOD0
168 #define SPCMD_SPIMOD_QUAD	SPCMD_SPIMOD1
169 #define SPCMD_SPRW		0x0010	/* SPI Read/Write Access (Dual/Quad) */
170 #define SPCMD_SSLA_MASK		0x0030	/* SSL Assert Signal Setting (RSPI) */
171 #define SPCMD_BRDV_MASK		0x000c	/* Bit Rate Division Setting */
172 #define SPCMD_CPOL		0x0002	/* Clock Polarity Setting */
173 #define SPCMD_CPHA		0x0001	/* Clock Phase Setting */
174 
175 /* SPBFCR - Buffer Control Register */
176 #define SPBFCR_TXRST		0x80	/* Transmit Buffer Data Reset */
177 #define SPBFCR_RXRST		0x40	/* Receive Buffer Data Reset */
178 #define SPBFCR_TXTRG_MASK	0x30	/* Transmit Buffer Data Triggering Number */
179 #define SPBFCR_RXTRG_MASK	0x07	/* Receive Buffer Data Triggering Number */
180 /* QSPI on R-Car Gen2 */
181 #define SPBFCR_TXTRG_1B		0x00	/* 31 bytes (1 byte available) */
182 #define SPBFCR_TXTRG_32B	0x30	/* 0 byte (32 bytes available) */
183 #define SPBFCR_RXTRG_1B		0x00	/* 1 byte (31 bytes available) */
184 #define SPBFCR_RXTRG_32B	0x07	/* 32 bytes (0 byte available) */
185 
186 #define QSPI_BUFFER_SIZE        32u
187 
188 struct rspi_data {
189 	void __iomem *addr;
190 	u32 max_speed_hz;
191 	struct spi_master *master;
192 	wait_queue_head_t wait;
193 	struct clk *clk;
194 	u16 spcmd;
195 	u8 spsr;
196 	u8 sppcr;
197 	int rx_irq, tx_irq;
198 	const struct spi_ops *ops;
199 
200 	unsigned dma_callbacked:1;
201 	unsigned byte_access:1;
202 };
203 
204 static void rspi_write8(const struct rspi_data *rspi, u8 data, u16 offset)
205 {
206 	iowrite8(data, rspi->addr + offset);
207 }
208 
209 static void rspi_write16(const struct rspi_data *rspi, u16 data, u16 offset)
210 {
211 	iowrite16(data, rspi->addr + offset);
212 }
213 
214 static void rspi_write32(const struct rspi_data *rspi, u32 data, u16 offset)
215 {
216 	iowrite32(data, rspi->addr + offset);
217 }
218 
219 static u8 rspi_read8(const struct rspi_data *rspi, u16 offset)
220 {
221 	return ioread8(rspi->addr + offset);
222 }
223 
224 static u16 rspi_read16(const struct rspi_data *rspi, u16 offset)
225 {
226 	return ioread16(rspi->addr + offset);
227 }
228 
229 static void rspi_write_data(const struct rspi_data *rspi, u16 data)
230 {
231 	if (rspi->byte_access)
232 		rspi_write8(rspi, data, RSPI_SPDR);
233 	else /* 16 bit */
234 		rspi_write16(rspi, data, RSPI_SPDR);
235 }
236 
237 static u16 rspi_read_data(const struct rspi_data *rspi)
238 {
239 	if (rspi->byte_access)
240 		return rspi_read8(rspi, RSPI_SPDR);
241 	else /* 16 bit */
242 		return rspi_read16(rspi, RSPI_SPDR);
243 }
244 
245 /* optional functions */
246 struct spi_ops {
247 	int (*set_config_register)(struct rspi_data *rspi, int access_size);
248 	int (*transfer_one)(struct spi_master *master, struct spi_device *spi,
249 			    struct spi_transfer *xfer);
250 	u16 mode_bits;
251 	u16 flags;
252 	u16 fifo_size;
253 };
254 
255 /*
256  * functions for RSPI on legacy SH
257  */
258 static int rspi_set_config_register(struct rspi_data *rspi, int access_size)
259 {
260 	int spbr;
261 
262 	/* Sets output mode, MOSI signal, and (optionally) loopback */
263 	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
264 
265 	/* Sets transfer bit rate */
266 	spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk),
267 			    2 * rspi->max_speed_hz) - 1;
268 	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
269 
270 	/* Disable dummy transmission, set 16-bit word access, 1 frame */
271 	rspi_write8(rspi, 0, RSPI_SPDCR);
272 	rspi->byte_access = 0;
273 
274 	/* Sets RSPCK, SSL, next-access delay value */
275 	rspi_write8(rspi, 0x00, RSPI_SPCKD);
276 	rspi_write8(rspi, 0x00, RSPI_SSLND);
277 	rspi_write8(rspi, 0x00, RSPI_SPND);
278 
279 	/* Sets parity, interrupt mask */
280 	rspi_write8(rspi, 0x00, RSPI_SPCR2);
281 
282 	/* Sets SPCMD */
283 	rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size);
284 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
285 
286 	/* Sets RSPI mode */
287 	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
288 
289 	return 0;
290 }
291 
292 /*
293  * functions for RSPI on RZ
294  */
295 static int rspi_rz_set_config_register(struct rspi_data *rspi, int access_size)
296 {
297 	int spbr;
298 
299 	/* Sets output mode, MOSI signal, and (optionally) loopback */
300 	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
301 
302 	/* Sets transfer bit rate */
303 	spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk),
304 			    2 * rspi->max_speed_hz) - 1;
305 	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
306 
307 	/* Disable dummy transmission, set byte access */
308 	rspi_write8(rspi, SPDCR_SPLBYTE, RSPI_SPDCR);
309 	rspi->byte_access = 1;
310 
311 	/* Sets RSPCK, SSL, next-access delay value */
312 	rspi_write8(rspi, 0x00, RSPI_SPCKD);
313 	rspi_write8(rspi, 0x00, RSPI_SSLND);
314 	rspi_write8(rspi, 0x00, RSPI_SPND);
315 
316 	/* Sets SPCMD */
317 	rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size);
318 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
319 
320 	/* Sets RSPI mode */
321 	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
322 
323 	return 0;
324 }
325 
326 /*
327  * functions for QSPI
328  */
329 static int qspi_set_config_register(struct rspi_data *rspi, int access_size)
330 {
331 	int spbr;
332 
333 	/* Sets output mode, MOSI signal, and (optionally) loopback */
334 	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
335 
336 	/* Sets transfer bit rate */
337 	spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk), 2 * rspi->max_speed_hz);
338 	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
339 
340 	/* Disable dummy transmission, set byte access */
341 	rspi_write8(rspi, 0, RSPI_SPDCR);
342 	rspi->byte_access = 1;
343 
344 	/* Sets RSPCK, SSL, next-access delay value */
345 	rspi_write8(rspi, 0x00, RSPI_SPCKD);
346 	rspi_write8(rspi, 0x00, RSPI_SSLND);
347 	rspi_write8(rspi, 0x00, RSPI_SPND);
348 
349 	/* Data Length Setting */
350 	if (access_size == 8)
351 		rspi->spcmd |= SPCMD_SPB_8BIT;
352 	else if (access_size == 16)
353 		rspi->spcmd |= SPCMD_SPB_16BIT;
354 	else
355 		rspi->spcmd |= SPCMD_SPB_32BIT;
356 
357 	rspi->spcmd |= SPCMD_SCKDEN | SPCMD_SLNDEN | SPCMD_SPNDEN;
358 
359 	/* Resets transfer data length */
360 	rspi_write32(rspi, 0, QSPI_SPBMUL0);
361 
362 	/* Resets transmit and receive buffer */
363 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
364 	/* Sets buffer to allow normal operation */
365 	rspi_write8(rspi, 0x00, QSPI_SPBFCR);
366 
367 	/* Sets SPCMD */
368 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
369 
370 	/* Enables SPI function in master mode */
371 	rspi_write8(rspi, SPCR_SPE | SPCR_MSTR, RSPI_SPCR);
372 
373 	return 0;
374 }
375 
376 static void qspi_update(const struct rspi_data *rspi, u8 mask, u8 val, u8 reg)
377 {
378 	u8 data;
379 
380 	data = rspi_read8(rspi, reg);
381 	data &= ~mask;
382 	data |= (val & mask);
383 	rspi_write8(rspi, data, reg);
384 }
385 
386 static int qspi_set_send_trigger(struct rspi_data *rspi, unsigned int len)
387 {
388 	unsigned int n;
389 
390 	n = min(len, QSPI_BUFFER_SIZE);
391 
392 	if (len >= QSPI_BUFFER_SIZE) {
393 		/* sets triggering number to 32 bytes */
394 		qspi_update(rspi, SPBFCR_TXTRG_MASK,
395 			     SPBFCR_TXTRG_32B, QSPI_SPBFCR);
396 	} else {
397 		/* sets triggering number to 1 byte */
398 		qspi_update(rspi, SPBFCR_TXTRG_MASK,
399 			     SPBFCR_TXTRG_1B, QSPI_SPBFCR);
400 	}
401 
402 	return n;
403 }
404 
405 static void qspi_set_receive_trigger(struct rspi_data *rspi, unsigned int len)
406 {
407 	unsigned int n;
408 
409 	n = min(len, QSPI_BUFFER_SIZE);
410 
411 	if (len >= QSPI_BUFFER_SIZE) {
412 		/* sets triggering number to 32 bytes */
413 		qspi_update(rspi, SPBFCR_RXTRG_MASK,
414 			     SPBFCR_RXTRG_32B, QSPI_SPBFCR);
415 	} else {
416 		/* sets triggering number to 1 byte */
417 		qspi_update(rspi, SPBFCR_RXTRG_MASK,
418 			     SPBFCR_RXTRG_1B, QSPI_SPBFCR);
419 	}
420 }
421 
422 #define set_config_register(spi, n) spi->ops->set_config_register(spi, n)
423 
424 static void rspi_enable_irq(const struct rspi_data *rspi, u8 enable)
425 {
426 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | enable, RSPI_SPCR);
427 }
428 
429 static void rspi_disable_irq(const struct rspi_data *rspi, u8 disable)
430 {
431 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~disable, RSPI_SPCR);
432 }
433 
434 static int rspi_wait_for_interrupt(struct rspi_data *rspi, u8 wait_mask,
435 				   u8 enable_bit)
436 {
437 	int ret;
438 
439 	rspi->spsr = rspi_read8(rspi, RSPI_SPSR);
440 	if (rspi->spsr & wait_mask)
441 		return 0;
442 
443 	rspi_enable_irq(rspi, enable_bit);
444 	ret = wait_event_timeout(rspi->wait, rspi->spsr & wait_mask, HZ);
445 	if (ret == 0 && !(rspi->spsr & wait_mask))
446 		return -ETIMEDOUT;
447 
448 	return 0;
449 }
450 
451 static inline int rspi_wait_for_tx_empty(struct rspi_data *rspi)
452 {
453 	return rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
454 }
455 
456 static inline int rspi_wait_for_rx_full(struct rspi_data *rspi)
457 {
458 	return rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE);
459 }
460 
461 static int rspi_data_out(struct rspi_data *rspi, u8 data)
462 {
463 	int error = rspi_wait_for_tx_empty(rspi);
464 	if (error < 0) {
465 		dev_err(&rspi->master->dev, "transmit timeout\n");
466 		return error;
467 	}
468 	rspi_write_data(rspi, data);
469 	return 0;
470 }
471 
472 static int rspi_data_in(struct rspi_data *rspi)
473 {
474 	int error;
475 	u8 data;
476 
477 	error = rspi_wait_for_rx_full(rspi);
478 	if (error < 0) {
479 		dev_err(&rspi->master->dev, "receive timeout\n");
480 		return error;
481 	}
482 	data = rspi_read_data(rspi);
483 	return data;
484 }
485 
486 static int rspi_pio_transfer(struct rspi_data *rspi, const u8 *tx, u8 *rx,
487 			     unsigned int n)
488 {
489 	while (n-- > 0) {
490 		if (tx) {
491 			int ret = rspi_data_out(rspi, *tx++);
492 			if (ret < 0)
493 				return ret;
494 		}
495 		if (rx) {
496 			int ret = rspi_data_in(rspi);
497 			if (ret < 0)
498 				return ret;
499 			*rx++ = ret;
500 		}
501 	}
502 
503 	return 0;
504 }
505 
506 static void rspi_dma_complete(void *arg)
507 {
508 	struct rspi_data *rspi = arg;
509 
510 	rspi->dma_callbacked = 1;
511 	wake_up_interruptible(&rspi->wait);
512 }
513 
514 static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
515 			     struct sg_table *rx)
516 {
517 	struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL;
518 	u8 irq_mask = 0;
519 	unsigned int other_irq = 0;
520 	dma_cookie_t cookie;
521 	int ret;
522 
523 	/* First prepare and submit the DMA request(s), as this may fail */
524 	if (rx) {
525 		desc_rx = dmaengine_prep_slave_sg(rspi->master->dma_rx,
526 					rx->sgl, rx->nents, DMA_FROM_DEVICE,
527 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
528 		if (!desc_rx) {
529 			ret = -EAGAIN;
530 			goto no_dma_rx;
531 		}
532 
533 		desc_rx->callback = rspi_dma_complete;
534 		desc_rx->callback_param = rspi;
535 		cookie = dmaengine_submit(desc_rx);
536 		if (dma_submit_error(cookie)) {
537 			ret = cookie;
538 			goto no_dma_rx;
539 		}
540 
541 		irq_mask |= SPCR_SPRIE;
542 	}
543 
544 	if (tx) {
545 		desc_tx = dmaengine_prep_slave_sg(rspi->master->dma_tx,
546 					tx->sgl, tx->nents, DMA_TO_DEVICE,
547 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
548 		if (!desc_tx) {
549 			ret = -EAGAIN;
550 			goto no_dma_tx;
551 		}
552 
553 		if (rx) {
554 			/* No callback */
555 			desc_tx->callback = NULL;
556 		} else {
557 			desc_tx->callback = rspi_dma_complete;
558 			desc_tx->callback_param = rspi;
559 		}
560 		cookie = dmaengine_submit(desc_tx);
561 		if (dma_submit_error(cookie)) {
562 			ret = cookie;
563 			goto no_dma_tx;
564 		}
565 
566 		irq_mask |= SPCR_SPTIE;
567 	}
568 
569 	/*
570 	 * DMAC needs SPxIE, but if SPxIE is set, the IRQ routine will be
571 	 * called. So, this driver disables the IRQ while DMA transfer.
572 	 */
573 	if (tx)
574 		disable_irq(other_irq = rspi->tx_irq);
575 	if (rx && rspi->rx_irq != other_irq)
576 		disable_irq(rspi->rx_irq);
577 
578 	rspi_enable_irq(rspi, irq_mask);
579 	rspi->dma_callbacked = 0;
580 
581 	/* Now start DMA */
582 	if (rx)
583 		dma_async_issue_pending(rspi->master->dma_rx);
584 	if (tx)
585 		dma_async_issue_pending(rspi->master->dma_tx);
586 
587 	ret = wait_event_interruptible_timeout(rspi->wait,
588 					       rspi->dma_callbacked, HZ);
589 	if (ret > 0 && rspi->dma_callbacked)
590 		ret = 0;
591 	else if (!ret) {
592 		dev_err(&rspi->master->dev, "DMA timeout\n");
593 		ret = -ETIMEDOUT;
594 		if (tx)
595 			dmaengine_terminate_all(rspi->master->dma_tx);
596 		if (rx)
597 			dmaengine_terminate_all(rspi->master->dma_rx);
598 	}
599 
600 	rspi_disable_irq(rspi, irq_mask);
601 
602 	if (tx)
603 		enable_irq(rspi->tx_irq);
604 	if (rx && rspi->rx_irq != other_irq)
605 		enable_irq(rspi->rx_irq);
606 
607 	return ret;
608 
609 no_dma_tx:
610 	if (rx)
611 		dmaengine_terminate_all(rspi->master->dma_rx);
612 no_dma_rx:
613 	if (ret == -EAGAIN) {
614 		pr_warn_once("%s %s: DMA not available, falling back to PIO\n",
615 			     dev_driver_string(&rspi->master->dev),
616 			     dev_name(&rspi->master->dev));
617 	}
618 	return ret;
619 }
620 
621 static void rspi_receive_init(const struct rspi_data *rspi)
622 {
623 	u8 spsr;
624 
625 	spsr = rspi_read8(rspi, RSPI_SPSR);
626 	if (spsr & SPSR_SPRF)
627 		rspi_read_data(rspi);	/* dummy read */
628 	if (spsr & SPSR_OVRF)
629 		rspi_write8(rspi, rspi_read8(rspi, RSPI_SPSR) & ~SPSR_OVRF,
630 			    RSPI_SPSR);
631 }
632 
633 static void rspi_rz_receive_init(const struct rspi_data *rspi)
634 {
635 	rspi_receive_init(rspi);
636 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, RSPI_SPBFCR);
637 	rspi_write8(rspi, 0, RSPI_SPBFCR);
638 }
639 
640 static void qspi_receive_init(const struct rspi_data *rspi)
641 {
642 	u8 spsr;
643 
644 	spsr = rspi_read8(rspi, RSPI_SPSR);
645 	if (spsr & SPSR_SPRF)
646 		rspi_read_data(rspi);   /* dummy read */
647 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
648 	rspi_write8(rspi, 0, QSPI_SPBFCR);
649 }
650 
651 static bool __rspi_can_dma(const struct rspi_data *rspi,
652 			   const struct spi_transfer *xfer)
653 {
654 	return xfer->len > rspi->ops->fifo_size;
655 }
656 
657 static bool rspi_can_dma(struct spi_master *master, struct spi_device *spi,
658 			 struct spi_transfer *xfer)
659 {
660 	struct rspi_data *rspi = spi_master_get_devdata(master);
661 
662 	return __rspi_can_dma(rspi, xfer);
663 }
664 
665 static int rspi_dma_check_then_transfer(struct rspi_data *rspi,
666 					 struct spi_transfer *xfer)
667 {
668 	if (!rspi->master->can_dma || !__rspi_can_dma(rspi, xfer))
669 		return -EAGAIN;
670 
671 	/* rx_buf can be NULL on RSPI on SH in TX-only Mode */
672 	return rspi_dma_transfer(rspi, &xfer->tx_sg,
673 				xfer->rx_buf ? &xfer->rx_sg : NULL);
674 }
675 
676 static int rspi_common_transfer(struct rspi_data *rspi,
677 				struct spi_transfer *xfer)
678 {
679 	int ret;
680 
681 	ret = rspi_dma_check_then_transfer(rspi, xfer);
682 	if (ret != -EAGAIN)
683 		return ret;
684 
685 	ret = rspi_pio_transfer(rspi, xfer->tx_buf, xfer->rx_buf, xfer->len);
686 	if (ret < 0)
687 		return ret;
688 
689 	/* Wait for the last transmission */
690 	rspi_wait_for_tx_empty(rspi);
691 
692 	return 0;
693 }
694 
695 static int rspi_transfer_one(struct spi_master *master, struct spi_device *spi,
696 			     struct spi_transfer *xfer)
697 {
698 	struct rspi_data *rspi = spi_master_get_devdata(master);
699 	u8 spcr;
700 
701 	spcr = rspi_read8(rspi, RSPI_SPCR);
702 	if (xfer->rx_buf) {
703 		rspi_receive_init(rspi);
704 		spcr &= ~SPCR_TXMD;
705 	} else {
706 		spcr |= SPCR_TXMD;
707 	}
708 	rspi_write8(rspi, spcr, RSPI_SPCR);
709 
710 	return rspi_common_transfer(rspi, xfer);
711 }
712 
713 static int rspi_rz_transfer_one(struct spi_master *master,
714 				struct spi_device *spi,
715 				struct spi_transfer *xfer)
716 {
717 	struct rspi_data *rspi = spi_master_get_devdata(master);
718 
719 	rspi_rz_receive_init(rspi);
720 
721 	return rspi_common_transfer(rspi, xfer);
722 }
723 
724 static int qspi_trigger_transfer_out_in(struct rspi_data *rspi, const u8 *tx,
725 					u8 *rx, unsigned int len)
726 {
727 	int i, n, ret;
728 	int error;
729 
730 	while (len > 0) {
731 		n = qspi_set_send_trigger(rspi, len);
732 		qspi_set_receive_trigger(rspi, len);
733 		if (n == QSPI_BUFFER_SIZE) {
734 			error = rspi_wait_for_tx_empty(rspi);
735 			if (error < 0) {
736 				dev_err(&rspi->master->dev, "transmit timeout\n");
737 				return error;
738 			}
739 			for (i = 0; i < n; i++)
740 				rspi_write_data(rspi, *tx++);
741 
742 			error = rspi_wait_for_rx_full(rspi);
743 			if (error < 0) {
744 				dev_err(&rspi->master->dev, "receive timeout\n");
745 				return error;
746 			}
747 			for (i = 0; i < n; i++)
748 				*rx++ = rspi_read_data(rspi);
749 		} else {
750 			ret = rspi_pio_transfer(rspi, tx, rx, n);
751 			if (ret < 0)
752 				return ret;
753 		}
754 		len -= n;
755 	}
756 
757 	return 0;
758 }
759 
760 static int qspi_transfer_out_in(struct rspi_data *rspi,
761 				struct spi_transfer *xfer)
762 {
763 	int ret;
764 
765 	qspi_receive_init(rspi);
766 
767 	ret = rspi_dma_check_then_transfer(rspi, xfer);
768 	if (ret != -EAGAIN)
769 		return ret;
770 
771 	return qspi_trigger_transfer_out_in(rspi, xfer->tx_buf,
772 					    xfer->rx_buf, xfer->len);
773 }
774 
775 static int qspi_transfer_out(struct rspi_data *rspi, struct spi_transfer *xfer)
776 {
777 	int ret;
778 
779 	if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer)) {
780 		ret = rspi_dma_transfer(rspi, &xfer->tx_sg, NULL);
781 		if (ret != -EAGAIN)
782 			return ret;
783 	}
784 
785 	ret = rspi_pio_transfer(rspi, xfer->tx_buf, NULL, xfer->len);
786 	if (ret < 0)
787 		return ret;
788 
789 	/* Wait for the last transmission */
790 	rspi_wait_for_tx_empty(rspi);
791 
792 	return 0;
793 }
794 
795 static int qspi_transfer_in(struct rspi_data *rspi, struct spi_transfer *xfer)
796 {
797 	if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer)) {
798 		int ret = rspi_dma_transfer(rspi, NULL, &xfer->rx_sg);
799 		if (ret != -EAGAIN)
800 			return ret;
801 	}
802 
803 	return rspi_pio_transfer(rspi, NULL, xfer->rx_buf, xfer->len);
804 }
805 
806 static int qspi_transfer_one(struct spi_master *master, struct spi_device *spi,
807 			     struct spi_transfer *xfer)
808 {
809 	struct rspi_data *rspi = spi_master_get_devdata(master);
810 
811 	if (spi->mode & SPI_LOOP) {
812 		return qspi_transfer_out_in(rspi, xfer);
813 	} else if (xfer->tx_nbits > SPI_NBITS_SINGLE) {
814 		/* Quad or Dual SPI Write */
815 		return qspi_transfer_out(rspi, xfer);
816 	} else if (xfer->rx_nbits > SPI_NBITS_SINGLE) {
817 		/* Quad or Dual SPI Read */
818 		return qspi_transfer_in(rspi, xfer);
819 	} else {
820 		/* Single SPI Transfer */
821 		return qspi_transfer_out_in(rspi, xfer);
822 	}
823 }
824 
825 static int rspi_setup(struct spi_device *spi)
826 {
827 	struct rspi_data *rspi = spi_master_get_devdata(spi->master);
828 
829 	rspi->max_speed_hz = spi->max_speed_hz;
830 
831 	rspi->spcmd = SPCMD_SSLKP;
832 	if (spi->mode & SPI_CPOL)
833 		rspi->spcmd |= SPCMD_CPOL;
834 	if (spi->mode & SPI_CPHA)
835 		rspi->spcmd |= SPCMD_CPHA;
836 
837 	/* CMOS output mode and MOSI signal from previous transfer */
838 	rspi->sppcr = 0;
839 	if (spi->mode & SPI_LOOP)
840 		rspi->sppcr |= SPPCR_SPLP;
841 
842 	set_config_register(rspi, 8);
843 
844 	return 0;
845 }
846 
847 static u16 qspi_transfer_mode(const struct spi_transfer *xfer)
848 {
849 	if (xfer->tx_buf)
850 		switch (xfer->tx_nbits) {
851 		case SPI_NBITS_QUAD:
852 			return SPCMD_SPIMOD_QUAD;
853 		case SPI_NBITS_DUAL:
854 			return SPCMD_SPIMOD_DUAL;
855 		default:
856 			return 0;
857 		}
858 	if (xfer->rx_buf)
859 		switch (xfer->rx_nbits) {
860 		case SPI_NBITS_QUAD:
861 			return SPCMD_SPIMOD_QUAD | SPCMD_SPRW;
862 		case SPI_NBITS_DUAL:
863 			return SPCMD_SPIMOD_DUAL | SPCMD_SPRW;
864 		default:
865 			return 0;
866 		}
867 
868 	return 0;
869 }
870 
871 static int qspi_setup_sequencer(struct rspi_data *rspi,
872 				const struct spi_message *msg)
873 {
874 	const struct spi_transfer *xfer;
875 	unsigned int i = 0, len = 0;
876 	u16 current_mode = 0xffff, mode;
877 
878 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
879 		mode = qspi_transfer_mode(xfer);
880 		if (mode == current_mode) {
881 			len += xfer->len;
882 			continue;
883 		}
884 
885 		/* Transfer mode change */
886 		if (i) {
887 			/* Set transfer data length of previous transfer */
888 			rspi_write32(rspi, len, QSPI_SPBMUL(i - 1));
889 		}
890 
891 		if (i >= QSPI_NUM_SPCMD) {
892 			dev_err(&msg->spi->dev,
893 				"Too many different transfer modes");
894 			return -EINVAL;
895 		}
896 
897 		/* Program transfer mode for this transfer */
898 		rspi_write16(rspi, rspi->spcmd | mode, RSPI_SPCMD(i));
899 		current_mode = mode;
900 		len = xfer->len;
901 		i++;
902 	}
903 	if (i) {
904 		/* Set final transfer data length and sequence length */
905 		rspi_write32(rspi, len, QSPI_SPBMUL(i - 1));
906 		rspi_write8(rspi, i - 1, RSPI_SPSCR);
907 	}
908 
909 	return 0;
910 }
911 
912 static int rspi_prepare_message(struct spi_master *master,
913 				struct spi_message *msg)
914 {
915 	struct rspi_data *rspi = spi_master_get_devdata(master);
916 	int ret;
917 
918 	if (msg->spi->mode &
919 	    (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD)) {
920 		/* Setup sequencer for messages with multiple transfer modes */
921 		ret = qspi_setup_sequencer(rspi, msg);
922 		if (ret < 0)
923 			return ret;
924 	}
925 
926 	/* Enable SPI function in master mode */
927 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_SPE, RSPI_SPCR);
928 	return 0;
929 }
930 
931 static int rspi_unprepare_message(struct spi_master *master,
932 				  struct spi_message *msg)
933 {
934 	struct rspi_data *rspi = spi_master_get_devdata(master);
935 
936 	/* Disable SPI function */
937 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_SPE, RSPI_SPCR);
938 
939 	/* Reset sequencer for Single SPI Transfers */
940 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
941 	rspi_write8(rspi, 0, RSPI_SPSCR);
942 	return 0;
943 }
944 
945 static irqreturn_t rspi_irq_mux(int irq, void *_sr)
946 {
947 	struct rspi_data *rspi = _sr;
948 	u8 spsr;
949 	irqreturn_t ret = IRQ_NONE;
950 	u8 disable_irq = 0;
951 
952 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
953 	if (spsr & SPSR_SPRF)
954 		disable_irq |= SPCR_SPRIE;
955 	if (spsr & SPSR_SPTEF)
956 		disable_irq |= SPCR_SPTIE;
957 
958 	if (disable_irq) {
959 		ret = IRQ_HANDLED;
960 		rspi_disable_irq(rspi, disable_irq);
961 		wake_up(&rspi->wait);
962 	}
963 
964 	return ret;
965 }
966 
967 static irqreturn_t rspi_irq_rx(int irq, void *_sr)
968 {
969 	struct rspi_data *rspi = _sr;
970 	u8 spsr;
971 
972 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
973 	if (spsr & SPSR_SPRF) {
974 		rspi_disable_irq(rspi, SPCR_SPRIE);
975 		wake_up(&rspi->wait);
976 		return IRQ_HANDLED;
977 	}
978 
979 	return 0;
980 }
981 
982 static irqreturn_t rspi_irq_tx(int irq, void *_sr)
983 {
984 	struct rspi_data *rspi = _sr;
985 	u8 spsr;
986 
987 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
988 	if (spsr & SPSR_SPTEF) {
989 		rspi_disable_irq(rspi, SPCR_SPTIE);
990 		wake_up(&rspi->wait);
991 		return IRQ_HANDLED;
992 	}
993 
994 	return 0;
995 }
996 
997 static struct dma_chan *rspi_request_dma_chan(struct device *dev,
998 					      enum dma_transfer_direction dir,
999 					      unsigned int id,
1000 					      dma_addr_t port_addr)
1001 {
1002 	dma_cap_mask_t mask;
1003 	struct dma_chan *chan;
1004 	struct dma_slave_config cfg;
1005 	int ret;
1006 
1007 	dma_cap_zero(mask);
1008 	dma_cap_set(DMA_SLAVE, mask);
1009 
1010 	chan = dma_request_slave_channel_compat(mask, shdma_chan_filter,
1011 				(void *)(unsigned long)id, dev,
1012 				dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1013 	if (!chan) {
1014 		dev_warn(dev, "dma_request_slave_channel_compat failed\n");
1015 		return NULL;
1016 	}
1017 
1018 	memset(&cfg, 0, sizeof(cfg));
1019 	cfg.direction = dir;
1020 	if (dir == DMA_MEM_TO_DEV) {
1021 		cfg.dst_addr = port_addr;
1022 		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1023 	} else {
1024 		cfg.src_addr = port_addr;
1025 		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1026 	}
1027 
1028 	ret = dmaengine_slave_config(chan, &cfg);
1029 	if (ret) {
1030 		dev_warn(dev, "dmaengine_slave_config failed %d\n", ret);
1031 		dma_release_channel(chan);
1032 		return NULL;
1033 	}
1034 
1035 	return chan;
1036 }
1037 
1038 static int rspi_request_dma(struct device *dev, struct spi_master *master,
1039 			    const struct resource *res)
1040 {
1041 	const struct rspi_plat_data *rspi_pd = dev_get_platdata(dev);
1042 	unsigned int dma_tx_id, dma_rx_id;
1043 
1044 	if (dev->of_node) {
1045 		/* In the OF case we will get the slave IDs from the DT */
1046 		dma_tx_id = 0;
1047 		dma_rx_id = 0;
1048 	} else if (rspi_pd && rspi_pd->dma_tx_id && rspi_pd->dma_rx_id) {
1049 		dma_tx_id = rspi_pd->dma_tx_id;
1050 		dma_rx_id = rspi_pd->dma_rx_id;
1051 	} else {
1052 		/* The driver assumes no error. */
1053 		return 0;
1054 	}
1055 
1056 	master->dma_tx = rspi_request_dma_chan(dev, DMA_MEM_TO_DEV, dma_tx_id,
1057 					       res->start + RSPI_SPDR);
1058 	if (!master->dma_tx)
1059 		return -ENODEV;
1060 
1061 	master->dma_rx = rspi_request_dma_chan(dev, DMA_DEV_TO_MEM, dma_rx_id,
1062 					       res->start + RSPI_SPDR);
1063 	if (!master->dma_rx) {
1064 		dma_release_channel(master->dma_tx);
1065 		master->dma_tx = NULL;
1066 		return -ENODEV;
1067 	}
1068 
1069 	master->can_dma = rspi_can_dma;
1070 	dev_info(dev, "DMA available");
1071 	return 0;
1072 }
1073 
1074 static void rspi_release_dma(struct spi_master *master)
1075 {
1076 	if (master->dma_tx)
1077 		dma_release_channel(master->dma_tx);
1078 	if (master->dma_rx)
1079 		dma_release_channel(master->dma_rx);
1080 }
1081 
1082 static int rspi_remove(struct platform_device *pdev)
1083 {
1084 	struct rspi_data *rspi = platform_get_drvdata(pdev);
1085 
1086 	rspi_release_dma(rspi->master);
1087 	pm_runtime_disable(&pdev->dev);
1088 
1089 	return 0;
1090 }
1091 
1092 static const struct spi_ops rspi_ops = {
1093 	.set_config_register =	rspi_set_config_register,
1094 	.transfer_one =		rspi_transfer_one,
1095 	.mode_bits =		SPI_CPHA | SPI_CPOL | SPI_LOOP,
1096 	.flags =		SPI_MASTER_MUST_TX,
1097 	.fifo_size =		8,
1098 };
1099 
1100 static const struct spi_ops rspi_rz_ops = {
1101 	.set_config_register =	rspi_rz_set_config_register,
1102 	.transfer_one =		rspi_rz_transfer_one,
1103 	.mode_bits =		SPI_CPHA | SPI_CPOL | SPI_LOOP,
1104 	.flags =		SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX,
1105 	.fifo_size =		8,	/* 8 for TX, 32 for RX */
1106 };
1107 
1108 static const struct spi_ops qspi_ops = {
1109 	.set_config_register =	qspi_set_config_register,
1110 	.transfer_one =		qspi_transfer_one,
1111 	.mode_bits =		SPI_CPHA | SPI_CPOL | SPI_LOOP |
1112 				SPI_TX_DUAL | SPI_TX_QUAD |
1113 				SPI_RX_DUAL | SPI_RX_QUAD,
1114 	.flags =		SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX,
1115 	.fifo_size =		32,
1116 };
1117 
1118 #ifdef CONFIG_OF
1119 static const struct of_device_id rspi_of_match[] = {
1120 	/* RSPI on legacy SH */
1121 	{ .compatible = "renesas,rspi", .data = &rspi_ops },
1122 	/* RSPI on RZ/A1H */
1123 	{ .compatible = "renesas,rspi-rz", .data = &rspi_rz_ops },
1124 	/* QSPI on R-Car Gen2 */
1125 	{ .compatible = "renesas,qspi", .data = &qspi_ops },
1126 	{ /* sentinel */ }
1127 };
1128 
1129 MODULE_DEVICE_TABLE(of, rspi_of_match);
1130 
1131 static int rspi_parse_dt(struct device *dev, struct spi_master *master)
1132 {
1133 	u32 num_cs;
1134 	int error;
1135 
1136 	/* Parse DT properties */
1137 	error = of_property_read_u32(dev->of_node, "num-cs", &num_cs);
1138 	if (error) {
1139 		dev_err(dev, "of_property_read_u32 num-cs failed %d\n", error);
1140 		return error;
1141 	}
1142 
1143 	master->num_chipselect = num_cs;
1144 	return 0;
1145 }
1146 #else
1147 #define rspi_of_match	NULL
1148 static inline int rspi_parse_dt(struct device *dev, struct spi_master *master)
1149 {
1150 	return -EINVAL;
1151 }
1152 #endif /* CONFIG_OF */
1153 
1154 static int rspi_request_irq(struct device *dev, unsigned int irq,
1155 			    irq_handler_t handler, const char *suffix,
1156 			    void *dev_id)
1157 {
1158 	const char *name = devm_kasprintf(dev, GFP_KERNEL, "%s:%s",
1159 					  dev_name(dev), suffix);
1160 	if (!name)
1161 		return -ENOMEM;
1162 
1163 	return devm_request_irq(dev, irq, handler, 0, name, dev_id);
1164 }
1165 
1166 static int rspi_probe(struct platform_device *pdev)
1167 {
1168 	struct resource *res;
1169 	struct spi_master *master;
1170 	struct rspi_data *rspi;
1171 	int ret;
1172 	const struct of_device_id *of_id;
1173 	const struct rspi_plat_data *rspi_pd;
1174 	const struct spi_ops *ops;
1175 
1176 	master = spi_alloc_master(&pdev->dev, sizeof(struct rspi_data));
1177 	if (master == NULL) {
1178 		dev_err(&pdev->dev, "spi_alloc_master error.\n");
1179 		return -ENOMEM;
1180 	}
1181 
1182 	of_id = of_match_device(rspi_of_match, &pdev->dev);
1183 	if (of_id) {
1184 		ops = of_id->data;
1185 		ret = rspi_parse_dt(&pdev->dev, master);
1186 		if (ret)
1187 			goto error1;
1188 	} else {
1189 		ops = (struct spi_ops *)pdev->id_entry->driver_data;
1190 		rspi_pd = dev_get_platdata(&pdev->dev);
1191 		if (rspi_pd && rspi_pd->num_chipselect)
1192 			master->num_chipselect = rspi_pd->num_chipselect;
1193 		else
1194 			master->num_chipselect = 2; /* default */
1195 	}
1196 
1197 	/* ops parameter check */
1198 	if (!ops->set_config_register) {
1199 		dev_err(&pdev->dev, "there is no set_config_register\n");
1200 		ret = -ENODEV;
1201 		goto error1;
1202 	}
1203 
1204 	rspi = spi_master_get_devdata(master);
1205 	platform_set_drvdata(pdev, rspi);
1206 	rspi->ops = ops;
1207 	rspi->master = master;
1208 
1209 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1210 	rspi->addr = devm_ioremap_resource(&pdev->dev, res);
1211 	if (IS_ERR(rspi->addr)) {
1212 		ret = PTR_ERR(rspi->addr);
1213 		goto error1;
1214 	}
1215 
1216 	rspi->clk = devm_clk_get(&pdev->dev, NULL);
1217 	if (IS_ERR(rspi->clk)) {
1218 		dev_err(&pdev->dev, "cannot get clock\n");
1219 		ret = PTR_ERR(rspi->clk);
1220 		goto error1;
1221 	}
1222 
1223 	pm_runtime_enable(&pdev->dev);
1224 
1225 	init_waitqueue_head(&rspi->wait);
1226 
1227 	master->bus_num = pdev->id;
1228 	master->setup = rspi_setup;
1229 	master->auto_runtime_pm = true;
1230 	master->transfer_one = ops->transfer_one;
1231 	master->prepare_message = rspi_prepare_message;
1232 	master->unprepare_message = rspi_unprepare_message;
1233 	master->mode_bits = ops->mode_bits;
1234 	master->flags = ops->flags;
1235 	master->dev.of_node = pdev->dev.of_node;
1236 
1237 	ret = platform_get_irq_byname(pdev, "rx");
1238 	if (ret < 0) {
1239 		ret = platform_get_irq_byname(pdev, "mux");
1240 		if (ret < 0)
1241 			ret = platform_get_irq(pdev, 0);
1242 		if (ret >= 0)
1243 			rspi->rx_irq = rspi->tx_irq = ret;
1244 	} else {
1245 		rspi->rx_irq = ret;
1246 		ret = platform_get_irq_byname(pdev, "tx");
1247 		if (ret >= 0)
1248 			rspi->tx_irq = ret;
1249 	}
1250 	if (ret < 0) {
1251 		dev_err(&pdev->dev, "platform_get_irq error\n");
1252 		goto error2;
1253 	}
1254 
1255 	if (rspi->rx_irq == rspi->tx_irq) {
1256 		/* Single multiplexed interrupt */
1257 		ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_mux,
1258 				       "mux", rspi);
1259 	} else {
1260 		/* Multi-interrupt mode, only SPRI and SPTI are used */
1261 		ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_rx,
1262 				       "rx", rspi);
1263 		if (!ret)
1264 			ret = rspi_request_irq(&pdev->dev, rspi->tx_irq,
1265 					       rspi_irq_tx, "tx", rspi);
1266 	}
1267 	if (ret < 0) {
1268 		dev_err(&pdev->dev, "request_irq error\n");
1269 		goto error2;
1270 	}
1271 
1272 	ret = rspi_request_dma(&pdev->dev, master, res);
1273 	if (ret < 0)
1274 		dev_warn(&pdev->dev, "DMA not available, using PIO\n");
1275 
1276 	ret = devm_spi_register_master(&pdev->dev, master);
1277 	if (ret < 0) {
1278 		dev_err(&pdev->dev, "spi_register_master error.\n");
1279 		goto error3;
1280 	}
1281 
1282 	dev_info(&pdev->dev, "probed\n");
1283 
1284 	return 0;
1285 
1286 error3:
1287 	rspi_release_dma(master);
1288 error2:
1289 	pm_runtime_disable(&pdev->dev);
1290 error1:
1291 	spi_master_put(master);
1292 
1293 	return ret;
1294 }
1295 
1296 static const struct platform_device_id spi_driver_ids[] = {
1297 	{ "rspi",	(kernel_ulong_t)&rspi_ops },
1298 	{ "rspi-rz",	(kernel_ulong_t)&rspi_rz_ops },
1299 	{ "qspi",	(kernel_ulong_t)&qspi_ops },
1300 	{},
1301 };
1302 
1303 MODULE_DEVICE_TABLE(platform, spi_driver_ids);
1304 
1305 static struct platform_driver rspi_driver = {
1306 	.probe =	rspi_probe,
1307 	.remove =	rspi_remove,
1308 	.id_table =	spi_driver_ids,
1309 	.driver		= {
1310 		.name = "renesas_spi",
1311 		.of_match_table = of_match_ptr(rspi_of_match),
1312 	},
1313 };
1314 module_platform_driver(rspi_driver);
1315 
1316 MODULE_DESCRIPTION("Renesas RSPI bus driver");
1317 MODULE_LICENSE("GPL v2");
1318 MODULE_AUTHOR("Yoshihiro Shimoda");
1319 MODULE_ALIAS("platform:rspi");
1320