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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 
rspi_write8(const struct rspi_data * rspi,u8 data,u16 offset)204 static void rspi_write8(const struct rspi_data *rspi, u8 data, u16 offset)
205 {
206 	iowrite8(data, rspi->addr + offset);
207 }
208 
rspi_write16(const struct rspi_data * rspi,u16 data,u16 offset)209 static void rspi_write16(const struct rspi_data *rspi, u16 data, u16 offset)
210 {
211 	iowrite16(data, rspi->addr + offset);
212 }
213 
rspi_write32(const struct rspi_data * rspi,u32 data,u16 offset)214 static void rspi_write32(const struct rspi_data *rspi, u32 data, u16 offset)
215 {
216 	iowrite32(data, rspi->addr + offset);
217 }
218 
rspi_read8(const struct rspi_data * rspi,u16 offset)219 static u8 rspi_read8(const struct rspi_data *rspi, u16 offset)
220 {
221 	return ioread8(rspi->addr + offset);
222 }
223 
rspi_read16(const struct rspi_data * rspi,u16 offset)224 static u16 rspi_read16(const struct rspi_data *rspi, u16 offset)
225 {
226 	return ioread16(rspi->addr + offset);
227 }
228 
rspi_write_data(const struct rspi_data * rspi,u16 data)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 
rspi_read_data(const struct rspi_data * rspi)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  */
rspi_set_config_register(struct rspi_data * rspi,int access_size)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 	/* Resets sequencer */
283 	rspi_write8(rspi, 0, RSPI_SPSCR);
284 	rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size);
285 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
286 
287 	/* Sets RSPI mode */
288 	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
289 
290 	return 0;
291 }
292 
293 /*
294  * functions for RSPI on RZ
295  */
rspi_rz_set_config_register(struct rspi_data * rspi,int access_size)296 static int rspi_rz_set_config_register(struct rspi_data *rspi, int access_size)
297 {
298 	int spbr;
299 
300 	/* Sets output mode, MOSI signal, and (optionally) loopback */
301 	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
302 
303 	/* Sets transfer bit rate */
304 	spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk),
305 			    2 * rspi->max_speed_hz) - 1;
306 	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
307 
308 	/* Disable dummy transmission, set byte access */
309 	rspi_write8(rspi, SPDCR_SPLBYTE, RSPI_SPDCR);
310 	rspi->byte_access = 1;
311 
312 	/* Sets RSPCK, SSL, next-access delay value */
313 	rspi_write8(rspi, 0x00, RSPI_SPCKD);
314 	rspi_write8(rspi, 0x00, RSPI_SSLND);
315 	rspi_write8(rspi, 0x00, RSPI_SPND);
316 
317 	/* Resets sequencer */
318 	rspi_write8(rspi, 0, RSPI_SPSCR);
319 	rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size);
320 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
321 
322 	/* Sets RSPI mode */
323 	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
324 
325 	return 0;
326 }
327 
328 /*
329  * functions for QSPI
330  */
qspi_set_config_register(struct rspi_data * rspi,int access_size)331 static int qspi_set_config_register(struct rspi_data *rspi, int access_size)
332 {
333 	int spbr;
334 
335 	/* Sets output mode, MOSI signal, and (optionally) loopback */
336 	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
337 
338 	/* Sets transfer bit rate */
339 	spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk), 2 * rspi->max_speed_hz);
340 	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
341 
342 	/* Disable dummy transmission, set byte access */
343 	rspi_write8(rspi, 0, RSPI_SPDCR);
344 	rspi->byte_access = 1;
345 
346 	/* Sets RSPCK, SSL, next-access delay value */
347 	rspi_write8(rspi, 0x00, RSPI_SPCKD);
348 	rspi_write8(rspi, 0x00, RSPI_SSLND);
349 	rspi_write8(rspi, 0x00, RSPI_SPND);
350 
351 	/* Data Length Setting */
352 	if (access_size == 8)
353 		rspi->spcmd |= SPCMD_SPB_8BIT;
354 	else if (access_size == 16)
355 		rspi->spcmd |= SPCMD_SPB_16BIT;
356 	else
357 		rspi->spcmd |= SPCMD_SPB_32BIT;
358 
359 	rspi->spcmd |= SPCMD_SCKDEN | SPCMD_SLNDEN | SPCMD_SPNDEN;
360 
361 	/* Resets transfer data length */
362 	rspi_write32(rspi, 0, QSPI_SPBMUL0);
363 
364 	/* Resets transmit and receive buffer */
365 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
366 	/* Sets buffer to allow normal operation */
367 	rspi_write8(rspi, 0x00, QSPI_SPBFCR);
368 
369 	/* Resets sequencer */
370 	rspi_write8(rspi, 0, RSPI_SPSCR);
371 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
372 
373 	/* Enables SPI function in master mode */
374 	rspi_write8(rspi, SPCR_SPE | SPCR_MSTR, RSPI_SPCR);
375 
376 	return 0;
377 }
378 
qspi_update(const struct rspi_data * rspi,u8 mask,u8 val,u8 reg)379 static void qspi_update(const struct rspi_data *rspi, u8 mask, u8 val, u8 reg)
380 {
381 	u8 data;
382 
383 	data = rspi_read8(rspi, reg);
384 	data &= ~mask;
385 	data |= (val & mask);
386 	rspi_write8(rspi, data, reg);
387 }
388 
qspi_set_send_trigger(struct rspi_data * rspi,unsigned int len)389 static unsigned int qspi_set_send_trigger(struct rspi_data *rspi,
390 					  unsigned int len)
391 {
392 	unsigned int n;
393 
394 	n = min(len, QSPI_BUFFER_SIZE);
395 
396 	if (len >= QSPI_BUFFER_SIZE) {
397 		/* sets triggering number to 32 bytes */
398 		qspi_update(rspi, SPBFCR_TXTRG_MASK,
399 			     SPBFCR_TXTRG_32B, QSPI_SPBFCR);
400 	} else {
401 		/* sets triggering number to 1 byte */
402 		qspi_update(rspi, SPBFCR_TXTRG_MASK,
403 			     SPBFCR_TXTRG_1B, QSPI_SPBFCR);
404 	}
405 
406 	return n;
407 }
408 
qspi_set_receive_trigger(struct rspi_data * rspi,unsigned int len)409 static void qspi_set_receive_trigger(struct rspi_data *rspi, unsigned int len)
410 {
411 	unsigned int n;
412 
413 	n = min(len, QSPI_BUFFER_SIZE);
414 
415 	if (len >= QSPI_BUFFER_SIZE) {
416 		/* sets triggering number to 32 bytes */
417 		qspi_update(rspi, SPBFCR_RXTRG_MASK,
418 			     SPBFCR_RXTRG_32B, QSPI_SPBFCR);
419 	} else {
420 		/* sets triggering number to 1 byte */
421 		qspi_update(rspi, SPBFCR_RXTRG_MASK,
422 			     SPBFCR_RXTRG_1B, QSPI_SPBFCR);
423 	}
424 }
425 
426 #define set_config_register(spi, n) spi->ops->set_config_register(spi, n)
427 
rspi_enable_irq(const struct rspi_data * rspi,u8 enable)428 static void rspi_enable_irq(const struct rspi_data *rspi, u8 enable)
429 {
430 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | enable, RSPI_SPCR);
431 }
432 
rspi_disable_irq(const struct rspi_data * rspi,u8 disable)433 static void rspi_disable_irq(const struct rspi_data *rspi, u8 disable)
434 {
435 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~disable, RSPI_SPCR);
436 }
437 
rspi_wait_for_interrupt(struct rspi_data * rspi,u8 wait_mask,u8 enable_bit)438 static int rspi_wait_for_interrupt(struct rspi_data *rspi, u8 wait_mask,
439 				   u8 enable_bit)
440 {
441 	int ret;
442 
443 	rspi->spsr = rspi_read8(rspi, RSPI_SPSR);
444 	if (rspi->spsr & wait_mask)
445 		return 0;
446 
447 	rspi_enable_irq(rspi, enable_bit);
448 	ret = wait_event_timeout(rspi->wait, rspi->spsr & wait_mask, HZ);
449 	if (ret == 0 && !(rspi->spsr & wait_mask))
450 		return -ETIMEDOUT;
451 
452 	return 0;
453 }
454 
rspi_wait_for_tx_empty(struct rspi_data * rspi)455 static inline int rspi_wait_for_tx_empty(struct rspi_data *rspi)
456 {
457 	return rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
458 }
459 
rspi_wait_for_rx_full(struct rspi_data * rspi)460 static inline int rspi_wait_for_rx_full(struct rspi_data *rspi)
461 {
462 	return rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE);
463 }
464 
rspi_data_out(struct rspi_data * rspi,u8 data)465 static int rspi_data_out(struct rspi_data *rspi, u8 data)
466 {
467 	int error = rspi_wait_for_tx_empty(rspi);
468 	if (error < 0) {
469 		dev_err(&rspi->master->dev, "transmit timeout\n");
470 		return error;
471 	}
472 	rspi_write_data(rspi, data);
473 	return 0;
474 }
475 
rspi_data_in(struct rspi_data * rspi)476 static int rspi_data_in(struct rspi_data *rspi)
477 {
478 	int error;
479 	u8 data;
480 
481 	error = rspi_wait_for_rx_full(rspi);
482 	if (error < 0) {
483 		dev_err(&rspi->master->dev, "receive timeout\n");
484 		return error;
485 	}
486 	data = rspi_read_data(rspi);
487 	return data;
488 }
489 
rspi_pio_transfer(struct rspi_data * rspi,const u8 * tx,u8 * rx,unsigned int n)490 static int rspi_pio_transfer(struct rspi_data *rspi, const u8 *tx, u8 *rx,
491 			     unsigned int n)
492 {
493 	while (n-- > 0) {
494 		if (tx) {
495 			int ret = rspi_data_out(rspi, *tx++);
496 			if (ret < 0)
497 				return ret;
498 		}
499 		if (rx) {
500 			int ret = rspi_data_in(rspi);
501 			if (ret < 0)
502 				return ret;
503 			*rx++ = ret;
504 		}
505 	}
506 
507 	return 0;
508 }
509 
rspi_dma_complete(void * arg)510 static void rspi_dma_complete(void *arg)
511 {
512 	struct rspi_data *rspi = arg;
513 
514 	rspi->dma_callbacked = 1;
515 	wake_up_interruptible(&rspi->wait);
516 }
517 
rspi_dma_transfer(struct rspi_data * rspi,struct sg_table * tx,struct sg_table * rx)518 static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
519 			     struct sg_table *rx)
520 {
521 	struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL;
522 	u8 irq_mask = 0;
523 	unsigned int other_irq = 0;
524 	dma_cookie_t cookie;
525 	int ret;
526 
527 	/* First prepare and submit the DMA request(s), as this may fail */
528 	if (rx) {
529 		desc_rx = dmaengine_prep_slave_sg(rspi->master->dma_rx,
530 					rx->sgl, rx->nents, DMA_FROM_DEVICE,
531 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
532 		if (!desc_rx) {
533 			ret = -EAGAIN;
534 			goto no_dma_rx;
535 		}
536 
537 		desc_rx->callback = rspi_dma_complete;
538 		desc_rx->callback_param = rspi;
539 		cookie = dmaengine_submit(desc_rx);
540 		if (dma_submit_error(cookie)) {
541 			ret = cookie;
542 			goto no_dma_rx;
543 		}
544 
545 		irq_mask |= SPCR_SPRIE;
546 	}
547 
548 	if (tx) {
549 		desc_tx = dmaengine_prep_slave_sg(rspi->master->dma_tx,
550 					tx->sgl, tx->nents, DMA_TO_DEVICE,
551 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
552 		if (!desc_tx) {
553 			ret = -EAGAIN;
554 			goto no_dma_tx;
555 		}
556 
557 		if (rx) {
558 			/* No callback */
559 			desc_tx->callback = NULL;
560 		} else {
561 			desc_tx->callback = rspi_dma_complete;
562 			desc_tx->callback_param = rspi;
563 		}
564 		cookie = dmaengine_submit(desc_tx);
565 		if (dma_submit_error(cookie)) {
566 			ret = cookie;
567 			goto no_dma_tx;
568 		}
569 
570 		irq_mask |= SPCR_SPTIE;
571 	}
572 
573 	/*
574 	 * DMAC needs SPxIE, but if SPxIE is set, the IRQ routine will be
575 	 * called. So, this driver disables the IRQ while DMA transfer.
576 	 */
577 	if (tx)
578 		disable_irq(other_irq = rspi->tx_irq);
579 	if (rx && rspi->rx_irq != other_irq)
580 		disable_irq(rspi->rx_irq);
581 
582 	rspi_enable_irq(rspi, irq_mask);
583 	rspi->dma_callbacked = 0;
584 
585 	/* Now start DMA */
586 	if (rx)
587 		dma_async_issue_pending(rspi->master->dma_rx);
588 	if (tx)
589 		dma_async_issue_pending(rspi->master->dma_tx);
590 
591 	ret = wait_event_interruptible_timeout(rspi->wait,
592 					       rspi->dma_callbacked, HZ);
593 	if (ret > 0 && rspi->dma_callbacked) {
594 		ret = 0;
595 	} else {
596 		if (!ret) {
597 			dev_err(&rspi->master->dev, "DMA timeout\n");
598 			ret = -ETIMEDOUT;
599 		}
600 		if (tx)
601 			dmaengine_terminate_all(rspi->master->dma_tx);
602 		if (rx)
603 			dmaengine_terminate_all(rspi->master->dma_rx);
604 	}
605 
606 	rspi_disable_irq(rspi, irq_mask);
607 
608 	if (tx)
609 		enable_irq(rspi->tx_irq);
610 	if (rx && rspi->rx_irq != other_irq)
611 		enable_irq(rspi->rx_irq);
612 
613 	return ret;
614 
615 no_dma_tx:
616 	if (rx)
617 		dmaengine_terminate_all(rspi->master->dma_rx);
618 no_dma_rx:
619 	if (ret == -EAGAIN) {
620 		pr_warn_once("%s %s: DMA not available, falling back to PIO\n",
621 			     dev_driver_string(&rspi->master->dev),
622 			     dev_name(&rspi->master->dev));
623 	}
624 	return ret;
625 }
626 
rspi_receive_init(const struct rspi_data * rspi)627 static void rspi_receive_init(const struct rspi_data *rspi)
628 {
629 	u8 spsr;
630 
631 	spsr = rspi_read8(rspi, RSPI_SPSR);
632 	if (spsr & SPSR_SPRF)
633 		rspi_read_data(rspi);	/* dummy read */
634 	if (spsr & SPSR_OVRF)
635 		rspi_write8(rspi, rspi_read8(rspi, RSPI_SPSR) & ~SPSR_OVRF,
636 			    RSPI_SPSR);
637 }
638 
rspi_rz_receive_init(const struct rspi_data * rspi)639 static void rspi_rz_receive_init(const struct rspi_data *rspi)
640 {
641 	rspi_receive_init(rspi);
642 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, RSPI_SPBFCR);
643 	rspi_write8(rspi, 0, RSPI_SPBFCR);
644 }
645 
qspi_receive_init(const struct rspi_data * rspi)646 static void qspi_receive_init(const struct rspi_data *rspi)
647 {
648 	u8 spsr;
649 
650 	spsr = rspi_read8(rspi, RSPI_SPSR);
651 	if (spsr & SPSR_SPRF)
652 		rspi_read_data(rspi);   /* dummy read */
653 	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
654 	rspi_write8(rspi, 0, QSPI_SPBFCR);
655 }
656 
__rspi_can_dma(const struct rspi_data * rspi,const struct spi_transfer * xfer)657 static bool __rspi_can_dma(const struct rspi_data *rspi,
658 			   const struct spi_transfer *xfer)
659 {
660 	return xfer->len > rspi->ops->fifo_size;
661 }
662 
rspi_can_dma(struct spi_master * master,struct spi_device * spi,struct spi_transfer * xfer)663 static bool rspi_can_dma(struct spi_master *master, struct spi_device *spi,
664 			 struct spi_transfer *xfer)
665 {
666 	struct rspi_data *rspi = spi_master_get_devdata(master);
667 
668 	return __rspi_can_dma(rspi, xfer);
669 }
670 
rspi_dma_check_then_transfer(struct rspi_data * rspi,struct spi_transfer * xfer)671 static int rspi_dma_check_then_transfer(struct rspi_data *rspi,
672 					 struct spi_transfer *xfer)
673 {
674 	if (!rspi->master->can_dma || !__rspi_can_dma(rspi, xfer))
675 		return -EAGAIN;
676 
677 	/* rx_buf can be NULL on RSPI on SH in TX-only Mode */
678 	return rspi_dma_transfer(rspi, &xfer->tx_sg,
679 				xfer->rx_buf ? &xfer->rx_sg : NULL);
680 }
681 
rspi_common_transfer(struct rspi_data * rspi,struct spi_transfer * xfer)682 static int rspi_common_transfer(struct rspi_data *rspi,
683 				struct spi_transfer *xfer)
684 {
685 	int ret;
686 
687 	ret = rspi_dma_check_then_transfer(rspi, xfer);
688 	if (ret != -EAGAIN)
689 		return ret;
690 
691 	ret = rspi_pio_transfer(rspi, xfer->tx_buf, xfer->rx_buf, xfer->len);
692 	if (ret < 0)
693 		return ret;
694 
695 	/* Wait for the last transmission */
696 	rspi_wait_for_tx_empty(rspi);
697 
698 	return 0;
699 }
700 
rspi_transfer_one(struct spi_master * master,struct spi_device * spi,struct spi_transfer * xfer)701 static int rspi_transfer_one(struct spi_master *master, struct spi_device *spi,
702 			     struct spi_transfer *xfer)
703 {
704 	struct rspi_data *rspi = spi_master_get_devdata(master);
705 	u8 spcr;
706 
707 	spcr = rspi_read8(rspi, RSPI_SPCR);
708 	if (xfer->rx_buf) {
709 		rspi_receive_init(rspi);
710 		spcr &= ~SPCR_TXMD;
711 	} else {
712 		spcr |= SPCR_TXMD;
713 	}
714 	rspi_write8(rspi, spcr, RSPI_SPCR);
715 
716 	return rspi_common_transfer(rspi, xfer);
717 }
718 
rspi_rz_transfer_one(struct spi_master * master,struct spi_device * spi,struct spi_transfer * xfer)719 static int rspi_rz_transfer_one(struct spi_master *master,
720 				struct spi_device *spi,
721 				struct spi_transfer *xfer)
722 {
723 	struct rspi_data *rspi = spi_master_get_devdata(master);
724 
725 	rspi_rz_receive_init(rspi);
726 
727 	return rspi_common_transfer(rspi, xfer);
728 }
729 
qspi_trigger_transfer_out_in(struct rspi_data * rspi,const u8 * tx,u8 * rx,unsigned int len)730 static int qspi_trigger_transfer_out_in(struct rspi_data *rspi, const u8 *tx,
731 					u8 *rx, unsigned int len)
732 {
733 	unsigned int i, n;
734 	int ret;
735 
736 	while (len > 0) {
737 		n = qspi_set_send_trigger(rspi, len);
738 		qspi_set_receive_trigger(rspi, len);
739 		if (n == QSPI_BUFFER_SIZE) {
740 			ret = rspi_wait_for_tx_empty(rspi);
741 			if (ret < 0) {
742 				dev_err(&rspi->master->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->master->dev, "receive timeout\n");
751 				return ret;
752 			}
753 			for (i = 0; i < n; i++)
754 				*rx++ = rspi_read_data(rspi);
755 		} else {
756 			ret = rspi_pio_transfer(rspi, tx, rx, n);
757 			if (ret < 0)
758 				return ret;
759 		}
760 		len -= n;
761 	}
762 
763 	return 0;
764 }
765 
qspi_transfer_out_in(struct rspi_data * rspi,struct spi_transfer * xfer)766 static int qspi_transfer_out_in(struct rspi_data *rspi,
767 				struct spi_transfer *xfer)
768 {
769 	int ret;
770 
771 	qspi_receive_init(rspi);
772 
773 	ret = rspi_dma_check_then_transfer(rspi, xfer);
774 	if (ret != -EAGAIN)
775 		return ret;
776 
777 	return qspi_trigger_transfer_out_in(rspi, xfer->tx_buf,
778 					    xfer->rx_buf, xfer->len);
779 }
780 
qspi_transfer_out(struct rspi_data * rspi,struct spi_transfer * xfer)781 static int qspi_transfer_out(struct rspi_data *rspi, struct spi_transfer *xfer)
782 {
783 	int ret;
784 
785 	if (rspi->master->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 	ret = rspi_pio_transfer(rspi, xfer->tx_buf, NULL, xfer->len);
792 	if (ret < 0)
793 		return ret;
794 
795 	/* Wait for the last transmission */
796 	rspi_wait_for_tx_empty(rspi);
797 
798 	return 0;
799 }
800 
qspi_transfer_in(struct rspi_data * rspi,struct spi_transfer * xfer)801 static int qspi_transfer_in(struct rspi_data *rspi, struct spi_transfer *xfer)
802 {
803 	if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer)) {
804 		int ret = rspi_dma_transfer(rspi, NULL, &xfer->rx_sg);
805 		if (ret != -EAGAIN)
806 			return ret;
807 	}
808 
809 	return rspi_pio_transfer(rspi, NULL, xfer->rx_buf, xfer->len);
810 }
811 
qspi_transfer_one(struct spi_master * master,struct spi_device * spi,struct spi_transfer * xfer)812 static int qspi_transfer_one(struct spi_master *master, struct spi_device *spi,
813 			     struct spi_transfer *xfer)
814 {
815 	struct rspi_data *rspi = spi_master_get_devdata(master);
816 
817 	if (spi->mode & SPI_LOOP) {
818 		return qspi_transfer_out_in(rspi, xfer);
819 	} else if (xfer->tx_nbits > SPI_NBITS_SINGLE) {
820 		/* Quad or Dual SPI Write */
821 		return qspi_transfer_out(rspi, xfer);
822 	} else if (xfer->rx_nbits > SPI_NBITS_SINGLE) {
823 		/* Quad or Dual SPI Read */
824 		return qspi_transfer_in(rspi, xfer);
825 	} else {
826 		/* Single SPI Transfer */
827 		return qspi_transfer_out_in(rspi, xfer);
828 	}
829 }
830 
rspi_setup(struct spi_device * spi)831 static int rspi_setup(struct spi_device *spi)
832 {
833 	struct rspi_data *rspi = spi_master_get_devdata(spi->master);
834 
835 	rspi->max_speed_hz = spi->max_speed_hz;
836 
837 	rspi->spcmd = SPCMD_SSLKP;
838 	if (spi->mode & SPI_CPOL)
839 		rspi->spcmd |= SPCMD_CPOL;
840 	if (spi->mode & SPI_CPHA)
841 		rspi->spcmd |= SPCMD_CPHA;
842 
843 	/* CMOS output mode and MOSI signal from previous transfer */
844 	rspi->sppcr = 0;
845 	if (spi->mode & SPI_LOOP)
846 		rspi->sppcr |= SPPCR_SPLP;
847 
848 	set_config_register(rspi, 8);
849 
850 	return 0;
851 }
852 
qspi_transfer_mode(const struct spi_transfer * xfer)853 static u16 qspi_transfer_mode(const struct spi_transfer *xfer)
854 {
855 	if (xfer->tx_buf)
856 		switch (xfer->tx_nbits) {
857 		case SPI_NBITS_QUAD:
858 			return SPCMD_SPIMOD_QUAD;
859 		case SPI_NBITS_DUAL:
860 			return SPCMD_SPIMOD_DUAL;
861 		default:
862 			return 0;
863 		}
864 	if (xfer->rx_buf)
865 		switch (xfer->rx_nbits) {
866 		case SPI_NBITS_QUAD:
867 			return SPCMD_SPIMOD_QUAD | SPCMD_SPRW;
868 		case SPI_NBITS_DUAL:
869 			return SPCMD_SPIMOD_DUAL | SPCMD_SPRW;
870 		default:
871 			return 0;
872 		}
873 
874 	return 0;
875 }
876 
qspi_setup_sequencer(struct rspi_data * rspi,const struct spi_message * msg)877 static int qspi_setup_sequencer(struct rspi_data *rspi,
878 				const struct spi_message *msg)
879 {
880 	const struct spi_transfer *xfer;
881 	unsigned int i = 0, len = 0;
882 	u16 current_mode = 0xffff, mode;
883 
884 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
885 		mode = qspi_transfer_mode(xfer);
886 		if (mode == current_mode) {
887 			len += xfer->len;
888 			continue;
889 		}
890 
891 		/* Transfer mode change */
892 		if (i) {
893 			/* Set transfer data length of previous transfer */
894 			rspi_write32(rspi, len, QSPI_SPBMUL(i - 1));
895 		}
896 
897 		if (i >= QSPI_NUM_SPCMD) {
898 			dev_err(&msg->spi->dev,
899 				"Too many different transfer modes");
900 			return -EINVAL;
901 		}
902 
903 		/* Program transfer mode for this transfer */
904 		rspi_write16(rspi, rspi->spcmd | mode, RSPI_SPCMD(i));
905 		current_mode = mode;
906 		len = xfer->len;
907 		i++;
908 	}
909 	if (i) {
910 		/* Set final transfer data length and sequence length */
911 		rspi_write32(rspi, len, QSPI_SPBMUL(i - 1));
912 		rspi_write8(rspi, i - 1, RSPI_SPSCR);
913 	}
914 
915 	return 0;
916 }
917 
rspi_prepare_message(struct spi_master * master,struct spi_message * msg)918 static int rspi_prepare_message(struct spi_master *master,
919 				struct spi_message *msg)
920 {
921 	struct rspi_data *rspi = spi_master_get_devdata(master);
922 	int ret;
923 
924 	if (msg->spi->mode &
925 	    (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD)) {
926 		/* Setup sequencer for messages with multiple transfer modes */
927 		ret = qspi_setup_sequencer(rspi, msg);
928 		if (ret < 0)
929 			return ret;
930 	}
931 
932 	/* Enable SPI function in master mode */
933 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_SPE, RSPI_SPCR);
934 	return 0;
935 }
936 
rspi_unprepare_message(struct spi_master * master,struct spi_message * msg)937 static int rspi_unprepare_message(struct spi_master *master,
938 				  struct spi_message *msg)
939 {
940 	struct rspi_data *rspi = spi_master_get_devdata(master);
941 
942 	/* Disable SPI function */
943 	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_SPE, RSPI_SPCR);
944 
945 	/* Reset sequencer for Single SPI Transfers */
946 	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
947 	rspi_write8(rspi, 0, RSPI_SPSCR);
948 	return 0;
949 }
950 
rspi_irq_mux(int irq,void * _sr)951 static irqreturn_t rspi_irq_mux(int irq, void *_sr)
952 {
953 	struct rspi_data *rspi = _sr;
954 	u8 spsr;
955 	irqreturn_t ret = IRQ_NONE;
956 	u8 disable_irq = 0;
957 
958 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
959 	if (spsr & SPSR_SPRF)
960 		disable_irq |= SPCR_SPRIE;
961 	if (spsr & SPSR_SPTEF)
962 		disable_irq |= SPCR_SPTIE;
963 
964 	if (disable_irq) {
965 		ret = IRQ_HANDLED;
966 		rspi_disable_irq(rspi, disable_irq);
967 		wake_up(&rspi->wait);
968 	}
969 
970 	return ret;
971 }
972 
rspi_irq_rx(int irq,void * _sr)973 static irqreturn_t rspi_irq_rx(int irq, void *_sr)
974 {
975 	struct rspi_data *rspi = _sr;
976 	u8 spsr;
977 
978 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
979 	if (spsr & SPSR_SPRF) {
980 		rspi_disable_irq(rspi, SPCR_SPRIE);
981 		wake_up(&rspi->wait);
982 		return IRQ_HANDLED;
983 	}
984 
985 	return 0;
986 }
987 
rspi_irq_tx(int irq,void * _sr)988 static irqreturn_t rspi_irq_tx(int irq, void *_sr)
989 {
990 	struct rspi_data *rspi = _sr;
991 	u8 spsr;
992 
993 	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
994 	if (spsr & SPSR_SPTEF) {
995 		rspi_disable_irq(rspi, SPCR_SPTIE);
996 		wake_up(&rspi->wait);
997 		return IRQ_HANDLED;
998 	}
999 
1000 	return 0;
1001 }
1002 
rspi_request_dma_chan(struct device * dev,enum dma_transfer_direction dir,unsigned int id,dma_addr_t port_addr)1003 static struct dma_chan *rspi_request_dma_chan(struct device *dev,
1004 					      enum dma_transfer_direction dir,
1005 					      unsigned int id,
1006 					      dma_addr_t port_addr)
1007 {
1008 	dma_cap_mask_t mask;
1009 	struct dma_chan *chan;
1010 	struct dma_slave_config cfg;
1011 	int ret;
1012 
1013 	dma_cap_zero(mask);
1014 	dma_cap_set(DMA_SLAVE, mask);
1015 
1016 	chan = dma_request_slave_channel_compat(mask, shdma_chan_filter,
1017 				(void *)(unsigned long)id, dev,
1018 				dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1019 	if (!chan) {
1020 		dev_warn(dev, "dma_request_slave_channel_compat failed\n");
1021 		return NULL;
1022 	}
1023 
1024 	memset(&cfg, 0, sizeof(cfg));
1025 	cfg.direction = dir;
1026 	if (dir == DMA_MEM_TO_DEV) {
1027 		cfg.dst_addr = port_addr;
1028 		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1029 	} else {
1030 		cfg.src_addr = port_addr;
1031 		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1032 	}
1033 
1034 	ret = dmaengine_slave_config(chan, &cfg);
1035 	if (ret) {
1036 		dev_warn(dev, "dmaengine_slave_config failed %d\n", ret);
1037 		dma_release_channel(chan);
1038 		return NULL;
1039 	}
1040 
1041 	return chan;
1042 }
1043 
rspi_request_dma(struct device * dev,struct spi_master * master,const struct resource * res)1044 static int rspi_request_dma(struct device *dev, struct spi_master *master,
1045 			    const struct resource *res)
1046 {
1047 	const struct rspi_plat_data *rspi_pd = dev_get_platdata(dev);
1048 	unsigned int dma_tx_id, dma_rx_id;
1049 
1050 	if (dev->of_node) {
1051 		/* In the OF case we will get the slave IDs from the DT */
1052 		dma_tx_id = 0;
1053 		dma_rx_id = 0;
1054 	} else if (rspi_pd && rspi_pd->dma_tx_id && rspi_pd->dma_rx_id) {
1055 		dma_tx_id = rspi_pd->dma_tx_id;
1056 		dma_rx_id = rspi_pd->dma_rx_id;
1057 	} else {
1058 		/* The driver assumes no error. */
1059 		return 0;
1060 	}
1061 
1062 	master->dma_tx = rspi_request_dma_chan(dev, DMA_MEM_TO_DEV, dma_tx_id,
1063 					       res->start + RSPI_SPDR);
1064 	if (!master->dma_tx)
1065 		return -ENODEV;
1066 
1067 	master->dma_rx = rspi_request_dma_chan(dev, DMA_DEV_TO_MEM, dma_rx_id,
1068 					       res->start + RSPI_SPDR);
1069 	if (!master->dma_rx) {
1070 		dma_release_channel(master->dma_tx);
1071 		master->dma_tx = NULL;
1072 		return -ENODEV;
1073 	}
1074 
1075 	master->can_dma = rspi_can_dma;
1076 	dev_info(dev, "DMA available");
1077 	return 0;
1078 }
1079 
rspi_release_dma(struct spi_master * master)1080 static void rspi_release_dma(struct spi_master *master)
1081 {
1082 	if (master->dma_tx)
1083 		dma_release_channel(master->dma_tx);
1084 	if (master->dma_rx)
1085 		dma_release_channel(master->dma_rx);
1086 }
1087 
rspi_remove(struct platform_device * pdev)1088 static int rspi_remove(struct platform_device *pdev)
1089 {
1090 	struct rspi_data *rspi = platform_get_drvdata(pdev);
1091 
1092 	rspi_release_dma(rspi->master);
1093 	pm_runtime_disable(&pdev->dev);
1094 
1095 	return 0;
1096 }
1097 
1098 static const struct spi_ops rspi_ops = {
1099 	.set_config_register =	rspi_set_config_register,
1100 	.transfer_one =		rspi_transfer_one,
1101 	.mode_bits =		SPI_CPHA | SPI_CPOL | SPI_LOOP,
1102 	.flags =		SPI_MASTER_MUST_TX,
1103 	.fifo_size =		8,
1104 };
1105 
1106 static const struct spi_ops rspi_rz_ops = {
1107 	.set_config_register =	rspi_rz_set_config_register,
1108 	.transfer_one =		rspi_rz_transfer_one,
1109 	.mode_bits =		SPI_CPHA | SPI_CPOL | SPI_LOOP,
1110 	.flags =		SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX,
1111 	.fifo_size =		8,	/* 8 for TX, 32 for RX */
1112 };
1113 
1114 static const struct spi_ops qspi_ops = {
1115 	.set_config_register =	qspi_set_config_register,
1116 	.transfer_one =		qspi_transfer_one,
1117 	.mode_bits =		SPI_CPHA | SPI_CPOL | SPI_LOOP |
1118 				SPI_TX_DUAL | SPI_TX_QUAD |
1119 				SPI_RX_DUAL | SPI_RX_QUAD,
1120 	.flags =		SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX,
1121 	.fifo_size =		32,
1122 };
1123 
1124 #ifdef CONFIG_OF
1125 static const struct of_device_id rspi_of_match[] = {
1126 	/* RSPI on legacy SH */
1127 	{ .compatible = "renesas,rspi", .data = &rspi_ops },
1128 	/* RSPI on RZ/A1H */
1129 	{ .compatible = "renesas,rspi-rz", .data = &rspi_rz_ops },
1130 	/* QSPI on R-Car Gen2 */
1131 	{ .compatible = "renesas,qspi", .data = &qspi_ops },
1132 	{ /* sentinel */ }
1133 };
1134 
1135 MODULE_DEVICE_TABLE(of, rspi_of_match);
1136 
rspi_parse_dt(struct device * dev,struct spi_master * master)1137 static int rspi_parse_dt(struct device *dev, struct spi_master *master)
1138 {
1139 	u32 num_cs;
1140 	int error;
1141 
1142 	/* Parse DT properties */
1143 	error = of_property_read_u32(dev->of_node, "num-cs", &num_cs);
1144 	if (error) {
1145 		dev_err(dev, "of_property_read_u32 num-cs failed %d\n", error);
1146 		return error;
1147 	}
1148 
1149 	master->num_chipselect = num_cs;
1150 	return 0;
1151 }
1152 #else
1153 #define rspi_of_match	NULL
rspi_parse_dt(struct device * dev,struct spi_master * master)1154 static inline int rspi_parse_dt(struct device *dev, struct spi_master *master)
1155 {
1156 	return -EINVAL;
1157 }
1158 #endif /* CONFIG_OF */
1159 
rspi_request_irq(struct device * dev,unsigned int irq,irq_handler_t handler,const char * suffix,void * dev_id)1160 static int rspi_request_irq(struct device *dev, unsigned int irq,
1161 			    irq_handler_t handler, const char *suffix,
1162 			    void *dev_id)
1163 {
1164 	const char *name = devm_kasprintf(dev, GFP_KERNEL, "%s:%s",
1165 					  dev_name(dev), suffix);
1166 	if (!name)
1167 		return -ENOMEM;
1168 
1169 	return devm_request_irq(dev, irq, handler, 0, name, dev_id);
1170 }
1171 
rspi_probe(struct platform_device * pdev)1172 static int rspi_probe(struct platform_device *pdev)
1173 {
1174 	struct resource *res;
1175 	struct spi_master *master;
1176 	struct rspi_data *rspi;
1177 	int ret;
1178 	const struct of_device_id *of_id;
1179 	const struct rspi_plat_data *rspi_pd;
1180 	const struct spi_ops *ops;
1181 
1182 	master = spi_alloc_master(&pdev->dev, sizeof(struct rspi_data));
1183 	if (master == NULL) {
1184 		dev_err(&pdev->dev, "spi_alloc_master error.\n");
1185 		return -ENOMEM;
1186 	}
1187 
1188 	of_id = of_match_device(rspi_of_match, &pdev->dev);
1189 	if (of_id) {
1190 		ops = of_id->data;
1191 		ret = rspi_parse_dt(&pdev->dev, master);
1192 		if (ret)
1193 			goto error1;
1194 	} else {
1195 		ops = (struct spi_ops *)pdev->id_entry->driver_data;
1196 		rspi_pd = dev_get_platdata(&pdev->dev);
1197 		if (rspi_pd && rspi_pd->num_chipselect)
1198 			master->num_chipselect = rspi_pd->num_chipselect;
1199 		else
1200 			master->num_chipselect = 2; /* default */
1201 	}
1202 
1203 	/* ops parameter check */
1204 	if (!ops->set_config_register) {
1205 		dev_err(&pdev->dev, "there is no set_config_register\n");
1206 		ret = -ENODEV;
1207 		goto error1;
1208 	}
1209 
1210 	rspi = spi_master_get_devdata(master);
1211 	platform_set_drvdata(pdev, rspi);
1212 	rspi->ops = ops;
1213 	rspi->master = master;
1214 
1215 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1216 	rspi->addr = devm_ioremap_resource(&pdev->dev, res);
1217 	if (IS_ERR(rspi->addr)) {
1218 		ret = PTR_ERR(rspi->addr);
1219 		goto error1;
1220 	}
1221 
1222 	rspi->clk = devm_clk_get(&pdev->dev, NULL);
1223 	if (IS_ERR(rspi->clk)) {
1224 		dev_err(&pdev->dev, "cannot get clock\n");
1225 		ret = PTR_ERR(rspi->clk);
1226 		goto error1;
1227 	}
1228 
1229 	pm_runtime_enable(&pdev->dev);
1230 
1231 	init_waitqueue_head(&rspi->wait);
1232 
1233 	master->bus_num = pdev->id;
1234 	master->setup = rspi_setup;
1235 	master->auto_runtime_pm = true;
1236 	master->transfer_one = ops->transfer_one;
1237 	master->prepare_message = rspi_prepare_message;
1238 	master->unprepare_message = rspi_unprepare_message;
1239 	master->mode_bits = ops->mode_bits;
1240 	master->flags = ops->flags;
1241 	master->dev.of_node = pdev->dev.of_node;
1242 
1243 	ret = platform_get_irq_byname(pdev, "rx");
1244 	if (ret < 0) {
1245 		ret = platform_get_irq_byname(pdev, "mux");
1246 		if (ret < 0)
1247 			ret = platform_get_irq(pdev, 0);
1248 		if (ret >= 0)
1249 			rspi->rx_irq = rspi->tx_irq = ret;
1250 	} else {
1251 		rspi->rx_irq = ret;
1252 		ret = platform_get_irq_byname(pdev, "tx");
1253 		if (ret >= 0)
1254 			rspi->tx_irq = ret;
1255 	}
1256 	if (ret < 0) {
1257 		dev_err(&pdev->dev, "platform_get_irq error\n");
1258 		goto error2;
1259 	}
1260 
1261 	if (rspi->rx_irq == rspi->tx_irq) {
1262 		/* Single multiplexed interrupt */
1263 		ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_mux,
1264 				       "mux", rspi);
1265 	} else {
1266 		/* Multi-interrupt mode, only SPRI and SPTI are used */
1267 		ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_rx,
1268 				       "rx", rspi);
1269 		if (!ret)
1270 			ret = rspi_request_irq(&pdev->dev, rspi->tx_irq,
1271 					       rspi_irq_tx, "tx", rspi);
1272 	}
1273 	if (ret < 0) {
1274 		dev_err(&pdev->dev, "request_irq error\n");
1275 		goto error2;
1276 	}
1277 
1278 	ret = rspi_request_dma(&pdev->dev, master, res);
1279 	if (ret < 0)
1280 		dev_warn(&pdev->dev, "DMA not available, using PIO\n");
1281 
1282 	ret = devm_spi_register_master(&pdev->dev, master);
1283 	if (ret < 0) {
1284 		dev_err(&pdev->dev, "spi_register_master error.\n");
1285 		goto error3;
1286 	}
1287 
1288 	dev_info(&pdev->dev, "probed\n");
1289 
1290 	return 0;
1291 
1292 error3:
1293 	rspi_release_dma(master);
1294 error2:
1295 	pm_runtime_disable(&pdev->dev);
1296 error1:
1297 	spi_master_put(master);
1298 
1299 	return ret;
1300 }
1301 
1302 static const struct platform_device_id spi_driver_ids[] = {
1303 	{ "rspi",	(kernel_ulong_t)&rspi_ops },
1304 	{ "rspi-rz",	(kernel_ulong_t)&rspi_rz_ops },
1305 	{ "qspi",	(kernel_ulong_t)&qspi_ops },
1306 	{},
1307 };
1308 
1309 MODULE_DEVICE_TABLE(platform, spi_driver_ids);
1310 
1311 #ifdef CONFIG_PM_SLEEP
rspi_suspend(struct device * dev)1312 static int rspi_suspend(struct device *dev)
1313 {
1314 	struct platform_device *pdev = to_platform_device(dev);
1315 	struct rspi_data *rspi = platform_get_drvdata(pdev);
1316 
1317 	return spi_master_suspend(rspi->master);
1318 }
1319 
rspi_resume(struct device * dev)1320 static int rspi_resume(struct device *dev)
1321 {
1322 	struct platform_device *pdev = to_platform_device(dev);
1323 	struct rspi_data *rspi = platform_get_drvdata(pdev);
1324 
1325 	return spi_master_resume(rspi->master);
1326 }
1327 
1328 static SIMPLE_DEV_PM_OPS(rspi_pm_ops, rspi_suspend, rspi_resume);
1329 #define DEV_PM_OPS	&rspi_pm_ops
1330 #else
1331 #define DEV_PM_OPS	NULL
1332 #endif /* CONFIG_PM_SLEEP */
1333 
1334 static struct platform_driver rspi_driver = {
1335 	.probe =	rspi_probe,
1336 	.remove =	rspi_remove,
1337 	.id_table =	spi_driver_ids,
1338 	.driver		= {
1339 		.name = "renesas_spi",
1340 		.pm = DEV_PM_OPS,
1341 		.of_match_table = of_match_ptr(rspi_of_match),
1342 	},
1343 };
1344 module_platform_driver(rspi_driver);
1345 
1346 MODULE_DESCRIPTION("Renesas RSPI bus driver");
1347 MODULE_LICENSE("GPL v2");
1348 MODULE_AUTHOR("Yoshihiro Shimoda");
1349 MODULE_ALIAS("platform:rspi");
1350