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ARM: 7989/1: Delete asm/system.h
[linux/fpc-iii.git] / drivers / spi / spi-rspi.c
blob28987d9fcfe5c9181f54d3b4e2afbbee0e47080c
1 /*
2 * SH RSPI driver
3 *
4 * Copyright (C) 2012 Renesas Solutions Corp.
5 *
6 * Based on spi-sh.c:
7 * Copyright (C) 2011 Renesas Solutions Corp.
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; version 2 of the License.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
21 *
22 */
23
24 #include <linux/module.h>
25 #include <linux/kernel.h>
26 #include <linux/sched.h>
27 #include <linux/errno.h>
28 #include <linux/list.h>
29 #include <linux/workqueue.h>
30 #include <linux/interrupt.h>
31 #include <linux/platform_device.h>
32 #include <linux/io.h>
33 #include <linux/clk.h>
34 #include <linux/dmaengine.h>
35 #include <linux/dma-mapping.h>
36 #include <linux/sh_dma.h>
37 #include <linux/spi/spi.h>
38 #include <linux/spi/rspi.h>
39
40 #define RSPI_SPCR 0x00 /* Control Register */
41 #define RSPI_SSLP 0x01 /* Slave Select Polarity Register */
42 #define RSPI_SPPCR 0x02 /* Pin Control Register */
43 #define RSPI_SPSR 0x03 /* Status Register */
44 #define RSPI_SPDR 0x04 /* Data Register */
45 #define RSPI_SPSCR 0x08 /* Sequence Control Register */
46 #define RSPI_SPSSR 0x09 /* Sequence Status Register */
47 #define RSPI_SPBR 0x0a /* Bit Rate Register */
48 #define RSPI_SPDCR 0x0b /* Data Control Register */
49 #define RSPI_SPCKD 0x0c /* Clock Delay Register */
50 #define RSPI_SSLND 0x0d /* Slave Select Negation Delay Register */
51 #define RSPI_SPND 0x0e /* Next-Access Delay Register */
52 #define RSPI_SPCR2 0x0f /* Control Register 2 */
53 #define RSPI_SPCMD0 0x10 /* Command Register 0 */
54 #define RSPI_SPCMD1 0x12 /* Command Register 1 */
55 #define RSPI_SPCMD2 0x14 /* Command Register 2 */
56 #define RSPI_SPCMD3 0x16 /* Command Register 3 */
57 #define RSPI_SPCMD4 0x18 /* Command Register 4 */
58 #define RSPI_SPCMD5 0x1a /* Command Register 5 */
59 #define RSPI_SPCMD6 0x1c /* Command Register 6 */
60 #define RSPI_SPCMD7 0x1e /* Command Register 7 */
61 #define RSPI_SPBFCR 0x20 /* Buffer Control Register */
62 #define RSPI_SPBFDR 0x22 /* Buffer Data Count Setting Register */
63
64 /*qspi only */
65 #define QSPI_SPBFCR 0x18 /* Buffer Control Register */
66 #define QSPI_SPBDCR 0x1a /* Buffer Data Count Register */
67 #define QSPI_SPBMUL0 0x1c /* Transfer Data Length Multiplier Setting Register 0 */
68 #define QSPI_SPBMUL1 0x20 /* Transfer Data Length Multiplier Setting Register 1 */
69 #define QSPI_SPBMUL2 0x24 /* Transfer Data Length Multiplier Setting Register 2 */
70 #define QSPI_SPBMUL3 0x28 /* Transfer Data Length Multiplier Setting Register 3 */
71
72 /* SPCR - Control Register */
73 #define SPCR_SPRIE 0x80 /* Receive Interrupt Enable */
74 #define SPCR_SPE 0x40 /* Function Enable */
75 #define SPCR_SPTIE 0x20 /* Transmit Interrupt Enable */
76 #define SPCR_SPEIE 0x10 /* Error Interrupt Enable */
77 #define SPCR_MSTR 0x08 /* Master/Slave Mode Select */
78 #define SPCR_MODFEN 0x04 /* Mode Fault Error Detection Enable */
79 /* RSPI on SH only */
80 #define SPCR_TXMD 0x02 /* TX Only Mode (vs. Full Duplex) */
81 #define SPCR_SPMS 0x01 /* 3-wire Mode (vs. 4-wire) */
82 /* QSPI on R-Car M2 only */
83 #define SPCR_WSWAP 0x02 /* Word Swap of read-data for DMAC */
84 #define SPCR_BSWAP 0x01 /* Byte Swap of read-data for DMAC */
85
86 /* SSLP - Slave Select Polarity Register */
87 #define SSLP_SSL1P 0x02 /* SSL1 Signal Polarity Setting */
88 #define SSLP_SSL0P 0x01 /* SSL0 Signal Polarity Setting */
89
90 /* SPPCR - Pin Control Register */
91 #define SPPCR_MOIFE 0x20 /* MOSI Idle Value Fixing Enable */
92 #define SPPCR_MOIFV 0x10 /* MOSI Idle Fixed Value */
93 #define SPPCR_SPOM 0x04
94 #define SPPCR_SPLP2 0x02 /* Loopback Mode 2 (non-inverting) */
95 #define SPPCR_SPLP 0x01 /* Loopback Mode (inverting) */
96
97 #define SPPCR_IO3FV 0x04 /* Single-/Dual-SPI Mode IO3 Output Fixed Value */
98 #define SPPCR_IO2FV 0x04 /* Single-/Dual-SPI Mode IO2 Output Fixed Value */
99
100 /* SPSR - Status Register */
101 #define SPSR_SPRF 0x80 /* Receive Buffer Full Flag */
102 #define SPSR_TEND 0x40 /* Transmit End */
103 #define SPSR_SPTEF 0x20 /* Transmit Buffer Empty Flag */
104 #define SPSR_PERF 0x08 /* Parity Error Flag */
105 #define SPSR_MODF 0x04 /* Mode Fault Error Flag */
106 #define SPSR_IDLNF 0x02 /* RSPI Idle Flag */
107 #define SPSR_OVRF 0x01 /* Overrun Error Flag */
108
109 /* SPSCR - Sequence Control Register */
110 #define SPSCR_SPSLN_MASK 0x07 /* Sequence Length Specification */
111
112 /* SPSSR - Sequence Status Register */
113 #define SPSSR_SPECM_MASK 0x70 /* Command Error Mask */
114 #define SPSSR_SPCP_MASK 0x07 /* Command Pointer Mask */
115
116 /* SPDCR - Data Control Register */
117 #define SPDCR_TXDMY 0x80 /* Dummy Data Transmission Enable */
118 #define SPDCR_SPLW1 0x40 /* Access Width Specification (RZ) */
119 #define SPDCR_SPLW0 0x20 /* Access Width Specification (RZ) */
120 #define SPDCR_SPLLWORD (SPDCR_SPLW1 | SPDCR_SPLW0)
121 #define SPDCR_SPLWORD SPDCR_SPLW1
122 #define SPDCR_SPLBYTE SPDCR_SPLW0
123 #define SPDCR_SPLW 0x20 /* Access Width Specification (SH) */
124 #define SPDCR_SPRDTD 0x10 /* Receive Transmit Data Select */
125 #define SPDCR_SLSEL1 0x08
126 #define SPDCR_SLSEL0 0x04
127 #define SPDCR_SLSEL_MASK 0x0c /* SSL1 Output Select */
128 #define SPDCR_SPFC1 0x02
129 #define SPDCR_SPFC0 0x01
130 #define SPDCR_SPFC_MASK 0x03 /* Frame Count Setting (1-4) */
131
132 /* SPCKD - Clock Delay Register */
133 #define SPCKD_SCKDL_MASK 0x07 /* Clock Delay Setting (1-8) */
134
135 /* SSLND - Slave Select Negation Delay Register */
136 #define SSLND_SLNDL_MASK 0x07 /* SSL Negation Delay Setting (1-8) */
137
138 /* SPND - Next-Access Delay Register */
139 #define SPND_SPNDL_MASK 0x07 /* Next-Access Delay Setting (1-8) */
140
141 /* SPCR2 - Control Register 2 */
142 #define SPCR2_PTE 0x08 /* Parity Self-Test Enable */
143 #define SPCR2_SPIE 0x04 /* Idle Interrupt Enable */
144 #define SPCR2_SPOE 0x02 /* Odd Parity Enable (vs. Even) */
145 #define SPCR2_SPPE 0x01 /* Parity Enable */
146
147 /* SPCMDn - Command Registers */
148 #define SPCMD_SCKDEN 0x8000 /* Clock Delay Setting Enable */
149 #define SPCMD_SLNDEN 0x4000 /* SSL Negation Delay Setting Enable */
150 #define SPCMD_SPNDEN 0x2000 /* Next-Access Delay Enable */
151 #define SPCMD_LSBF 0x1000 /* LSB First */
152 #define SPCMD_SPB_MASK 0x0f00 /* Data Length Setting */
153 #define SPCMD_SPB_8_TO_16(bit) (((bit - 1) << 8) & SPCMD_SPB_MASK)
154 #define SPCMD_SPB_8BIT 0x0000 /* qspi only */
155 #define SPCMD_SPB_16BIT 0x0100
156 #define SPCMD_SPB_20BIT 0x0000
157 #define SPCMD_SPB_24BIT 0x0100
158 #define SPCMD_SPB_32BIT 0x0200
159 #define SPCMD_SSLKP 0x0080 /* SSL Signal Level Keeping */
160 #define SPCMD_SPIMOD_MASK 0x0060 /* SPI Operating Mode (QSPI only) */
161 #define SPCMD_SPIMOD1 0x0040
162 #define SPCMD_SPIMOD0 0x0020
163 #define SPCMD_SPIMOD_SINGLE 0
164 #define SPCMD_SPIMOD_DUAL SPCMD_SPIMOD0
165 #define SPCMD_SPIMOD_QUAD SPCMD_SPIMOD1
166 #define SPCMD_SPRW 0x0010 /* SPI Read/Write Access (Dual/Quad) */
167 #define SPCMD_SSLA_MASK 0x0030 /* SSL Assert Signal Setting (RSPI) */
168 #define SPCMD_BRDV_MASK 0x000c /* Bit Rate Division Setting */
169 #define SPCMD_CPOL 0x0002 /* Clock Polarity Setting */
170 #define SPCMD_CPHA 0x0001 /* Clock Phase Setting */
171
172 /* SPBFCR - Buffer Control Register */
173 #define SPBFCR_TXRST 0x80 /* Transmit Buffer Data Reset (qspi only) */
174 #define SPBFCR_RXRST 0x40 /* Receive Buffer Data Reset (qspi only) */
175 #define SPBFCR_TXTRG_MASK 0x30 /* Transmit Buffer Data Triggering Number */
176 #define SPBFCR_RXTRG_MASK 0x07 /* Receive Buffer Data Triggering Number */
177
178 #define DUMMY_DATA 0x00
179
180 struct rspi_data {
181 void __iomem *addr;
182 u32 max_speed_hz;
183 struct spi_master *master;
184 struct list_head queue;
185 struct work_struct ws;
186 wait_queue_head_t wait;
187 spinlock_t lock;
188 struct clk *clk;
189 u8 spsr;
190 u16 spcmd;
191 const struct spi_ops *ops;
192
193 /* for dmaengine */
194 struct dma_chan *chan_tx;
195 struct dma_chan *chan_rx;
196 int irq;
197
198 unsigned dma_width_16bit:1;
199 unsigned dma_callbacked:1;
200 };
201
202 static void rspi_write8(const struct rspi_data *rspi, u8 data, u16 offset)
203 {
204 iowrite8(data, rspi->addr + offset);
205 }
206
207 static void rspi_write16(const struct rspi_data *rspi, u16 data, u16 offset)
208 {
209 iowrite16(data, rspi->addr + offset);
210 }
211
212 static void rspi_write32(const struct rspi_data *rspi, u32 data, u16 offset)
213 {
214 iowrite32(data, rspi->addr + offset);
215 }
216
217 static u8 rspi_read8(const struct rspi_data *rspi, u16 offset)
218 {
219 return ioread8(rspi->addr + offset);
220 }
221
222 static u16 rspi_read16(const struct rspi_data *rspi, u16 offset)
223 {
224 return ioread16(rspi->addr + offset);
225 }
226
227 /* optional functions */
228 struct spi_ops {
229 int (*set_config_register)(const struct rspi_data *rspi,
230 int access_size);
231 int (*send_pio)(struct rspi_data *rspi, struct spi_message *mesg,
232 struct spi_transfer *t);
233 int (*receive_pio)(struct rspi_data *rspi, struct spi_message *mesg,
234 struct spi_transfer *t);
235
236 };
237
238 /*
239 * functions for RSPI
240 */
241 static int rspi_set_config_register(const struct rspi_data *rspi,
242 int access_size)
243 {
244 int spbr;
245
246 /* Sets output mode(CMOS) and MOSI signal(from previous transfer) */
247 rspi_write8(rspi, 0x00, RSPI_SPPCR);
248
249 /* Sets transfer bit rate */
250 spbr = clk_get_rate(rspi->clk) / (2 * rspi->max_speed_hz) - 1;
251 rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
252
253 /* Sets number of frames to be used: 1 frame */
254 rspi_write8(rspi, 0x00, RSPI_SPDCR);
255
256 /* Sets RSPCK, SSL, next-access delay value */
257 rspi_write8(rspi, 0x00, RSPI_SPCKD);
258 rspi_write8(rspi, 0x00, RSPI_SSLND);
259 rspi_write8(rspi, 0x00, RSPI_SPND);
260
261 /* Sets parity, interrupt mask */
262 rspi_write8(rspi, 0x00, RSPI_SPCR2);
263
264 /* Sets SPCMD */
265 rspi_write16(rspi, SPCMD_SPB_8_TO_16(access_size) | rspi->spcmd,
266 RSPI_SPCMD0);
267
268 /* Sets RSPI mode */
269 rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
270
271 return 0;
272 }
273
274 /*
275 * functions for QSPI
276 */
277 static int qspi_set_config_register(const struct rspi_data *rspi,
278 int access_size)
279 {
280 u16 spcmd;
281 int spbr;
282
283 /* Sets output mode(CMOS) and MOSI signal(from previous transfer) */
284 rspi_write8(rspi, 0x00, RSPI_SPPCR);
285
286 /* Sets transfer bit rate */
287 spbr = clk_get_rate(rspi->clk) / (2 * rspi->max_speed_hz);
288 rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
289
290 /* Sets number of frames to be used: 1 frame */
291 rspi_write8(rspi, 0x00, RSPI_SPDCR);
292
293 /* Sets RSPCK, SSL, next-access delay value */
294 rspi_write8(rspi, 0x00, RSPI_SPCKD);
295 rspi_write8(rspi, 0x00, RSPI_SSLND);
296 rspi_write8(rspi, 0x00, RSPI_SPND);
297
298 /* Data Length Setting */
299 if (access_size == 8)
300 spcmd = SPCMD_SPB_8BIT;
301 else if (access_size == 16)
302 spcmd = SPCMD_SPB_16BIT;
303 else
304 spcmd = SPCMD_SPB_32BIT;
305
306 spcmd |= SPCMD_SCKDEN | SPCMD_SLNDEN | rspi->spcmd | SPCMD_SPNDEN;
307
308 /* Resets transfer data length */
309 rspi_write32(rspi, 0, QSPI_SPBMUL0);
310
311 /* Resets transmit and receive buffer */
312 rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
313 /* Sets buffer to allow normal operation */
314 rspi_write8(rspi, 0x00, QSPI_SPBFCR);
315
316 /* Sets SPCMD */
317 rspi_write16(rspi, spcmd, RSPI_SPCMD0);
318
319 /* Enables SPI function in a master mode */
320 rspi_write8(rspi, SPCR_SPE | SPCR_MSTR, RSPI_SPCR);
321
322 return 0;
323 }
324
325 #define set_config_register(spi, n) spi->ops->set_config_register(spi, n)
326
327 static void rspi_enable_irq(const struct rspi_data *rspi, u8 enable)
328 {
329 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | enable, RSPI_SPCR);
330 }
331
332 static void rspi_disable_irq(const struct rspi_data *rspi, u8 disable)
333 {
334 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~disable, RSPI_SPCR);
335 }
336
337 static int rspi_wait_for_interrupt(struct rspi_data *rspi, u8 wait_mask,
338 u8 enable_bit)
339 {
340 int ret;
341
342 rspi->spsr = rspi_read8(rspi, RSPI_SPSR);
343 rspi_enable_irq(rspi, enable_bit);
344 ret = wait_event_timeout(rspi->wait, rspi->spsr & wait_mask, HZ);
345 if (ret == 0 && !(rspi->spsr & wait_mask))
346 return -ETIMEDOUT;
347
348 return 0;
349 }
350
351 static void rspi_assert_ssl(const struct rspi_data *rspi)
352 {
353 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_SPE, RSPI_SPCR);
354 }
355
356 static void rspi_negate_ssl(const struct rspi_data *rspi)
357 {
358 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_SPE, RSPI_SPCR);
359 }
360
361 static int rspi_send_pio(struct rspi_data *rspi, struct spi_message *mesg,
362 struct spi_transfer *t)
363 {
364 int remain = t->len;
365 const u8 *data = t->tx_buf;
366 while (remain > 0) {
367 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_TXMD,
368 RSPI_SPCR);
369
370 if (rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE) < 0) {
371 dev_err(&rspi->master->dev,
372 "%s: tx empty timeout\n", __func__);
373 return -ETIMEDOUT;
374 }
375
376 rspi_write16(rspi, *data, RSPI_SPDR);
377 data++;
378 remain--;
379 }
380
381 /* Waiting for the last transmission */
382 rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
383
384 return 0;
385 }
386
387 static int qspi_send_pio(struct rspi_data *rspi, struct spi_message *mesg,
388 struct spi_transfer *t)
389 {
390 int remain = t->len;
391 const u8 *data = t->tx_buf;
392
393 rspi_write8(rspi, SPBFCR_TXRST, QSPI_SPBFCR);
394 rspi_write8(rspi, 0x00, QSPI_SPBFCR);
395
396 while (remain > 0) {
397
398 if (rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE) < 0) {
399 dev_err(&rspi->master->dev,
400 "%s: tx empty timeout\n", __func__);
401 return -ETIMEDOUT;
402 }
403 rspi_write8(rspi, *data++, RSPI_SPDR);
404
405 if (rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE) < 0) {
406 dev_err(&rspi->master->dev,
407 "%s: receive timeout\n", __func__);
408 return -ETIMEDOUT;
409 }
410 rspi_read8(rspi, RSPI_SPDR);
411
412 remain--;
413 }
414
415 /* Waiting for the last transmission */
416 rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
417
418 return 0;
419 }
420
421 #define send_pio(spi, mesg, t) spi->ops->send_pio(spi, mesg, t)
422
423 static void rspi_dma_complete(void *arg)
424 {
425 struct rspi_data *rspi = arg;
426
427 rspi->dma_callbacked = 1;
428 wake_up_interruptible(&rspi->wait);
429 }
430
431 static int rspi_dma_map_sg(struct scatterlist *sg, const void *buf,
432 unsigned len, struct dma_chan *chan,
433 enum dma_transfer_direction dir)
434 {
435 sg_init_table(sg, 1);
436 sg_set_buf(sg, buf, len);
437 sg_dma_len(sg) = len;
438 return dma_map_sg(chan->device->dev, sg, 1, dir);
439 }
440
441 static void rspi_dma_unmap_sg(struct scatterlist *sg, struct dma_chan *chan,
442 enum dma_transfer_direction dir)
443 {
444 dma_unmap_sg(chan->device->dev, sg, 1, dir);
445 }
446
447 static void rspi_memory_to_8bit(void *buf, const void *data, unsigned len)
448 {
449 u16 *dst = buf;
450 const u8 *src = data;
451
452 while (len) {
453 *dst++ = (u16)(*src++);
454 len--;
455 }
456 }
457
458 static void rspi_memory_from_8bit(void *buf, const void *data, unsigned len)
459 {
460 u8 *dst = buf;
461 const u16 *src = data;
462
463 while (len) {
464 *dst++ = (u8)*src++;
465 len--;
466 }
467 }
468
469 static int rspi_send_dma(struct rspi_data *rspi, struct spi_transfer *t)
470 {
471 struct scatterlist sg;
472 const void *buf = NULL;
473 struct dma_async_tx_descriptor *desc;
474 unsigned len;
475 int ret = 0;
476
477 if (rspi->dma_width_16bit) {
478 void *tmp;
479 /*
480 * If DMAC bus width is 16-bit, the driver allocates a dummy
481 * buffer. And, the driver converts original data into the
482 * DMAC data as the following format:
483 * original data: 1st byte, 2nd byte ...
484 * DMAC data: 1st byte, dummy, 2nd byte, dummy ...
485 */
486 len = t->len * 2;
487 tmp = kmalloc(len, GFP_KERNEL);
488 if (!tmp)
489 return -ENOMEM;
490 rspi_memory_to_8bit(tmp, t->tx_buf, t->len);
491 buf = tmp;
492 } else {
493 len = t->len;
494 buf = t->tx_buf;
495 }
496
497 if (!rspi_dma_map_sg(&sg, buf, len, rspi->chan_tx, DMA_TO_DEVICE)) {
498 ret = -EFAULT;
499 goto end_nomap;
500 }
501 desc = dmaengine_prep_slave_sg(rspi->chan_tx, &sg, 1, DMA_TO_DEVICE,
502 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
503 if (!desc) {
504 ret = -EIO;
505 goto end;
506 }
507
508 /*
509 * DMAC needs SPTIE, but if SPTIE is set, this IRQ routine will be
510 * called. So, this driver disables the IRQ while DMA transfer.
511 */
512 disable_irq(rspi->irq);
513
514 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_TXMD, RSPI_SPCR);
515 rspi_enable_irq(rspi, SPCR_SPTIE);
516 rspi->dma_callbacked = 0;
517
518 desc->callback = rspi_dma_complete;
519 desc->callback_param = rspi;
520 dmaengine_submit(desc);
521 dma_async_issue_pending(rspi->chan_tx);
522
523 ret = wait_event_interruptible_timeout(rspi->wait,
524 rspi->dma_callbacked, HZ);
525 if (ret > 0 && rspi->dma_callbacked)
526 ret = 0;
527 else if (!ret)
528 ret = -ETIMEDOUT;
529 rspi_disable_irq(rspi, SPCR_SPTIE);
530
531 enable_irq(rspi->irq);
532
533 end:
534 rspi_dma_unmap_sg(&sg, rspi->chan_tx, DMA_TO_DEVICE);
535 end_nomap:
536 if (rspi->dma_width_16bit)
537 kfree(buf);
538
539 return ret;
540 }
541
542 static void rspi_receive_init(const struct rspi_data *rspi)
543 {
544 u8 spsr;
545
546 spsr = rspi_read8(rspi, RSPI_SPSR);
547 if (spsr & SPSR_SPRF)
548 rspi_read16(rspi, RSPI_SPDR); /* dummy read */
549 if (spsr & SPSR_OVRF)
550 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPSR) & ~SPSR_OVRF,
551 RSPI_SPSR);
552 }
553
554 static int rspi_receive_pio(struct rspi_data *rspi, struct spi_message *mesg,
555 struct spi_transfer *t)
556 {
557 int remain = t->len;
558 u8 *data;
559
560 rspi_receive_init(rspi);
561
562 data = t->rx_buf;
563 while (remain > 0) {
564 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_TXMD,
565 RSPI_SPCR);
566
567 if (rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE) < 0) {
568 dev_err(&rspi->master->dev,
569 "%s: tx empty timeout\n", __func__);
570 return -ETIMEDOUT;
571 }
572 /* dummy write for generate clock */
573 rspi_write16(rspi, DUMMY_DATA, RSPI_SPDR);
574
575 if (rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE) < 0) {
576 dev_err(&rspi->master->dev,
577 "%s: receive timeout\n", __func__);
578 return -ETIMEDOUT;
579 }
580 /* SPDR allows 16 or 32-bit access only */
581 *data = (u8)rspi_read16(rspi, RSPI_SPDR);
582
583 data++;
584 remain--;
585 }
586
587 return 0;
588 }
589
590 static void qspi_receive_init(const struct rspi_data *rspi)
591 {
592 u8 spsr;
593
594 spsr = rspi_read8(rspi, RSPI_SPSR);
595 if (spsr & SPSR_SPRF)
596 rspi_read8(rspi, RSPI_SPDR); /* dummy read */
597 rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
598 rspi_write8(rspi, 0x00, QSPI_SPBFCR);
599 }
600
601 static int qspi_receive_pio(struct rspi_data *rspi, struct spi_message *mesg,
602 struct spi_transfer *t)
603 {
604 int remain = t->len;
605 u8 *data;
606
607 qspi_receive_init(rspi);
608
609 data = t->rx_buf;
610 while (remain > 0) {
611
612 if (rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE) < 0) {
613 dev_err(&rspi->master->dev,
614 "%s: tx empty timeout\n", __func__);
615 return -ETIMEDOUT;
616 }
617 /* dummy write for generate clock */
618 rspi_write8(rspi, DUMMY_DATA, RSPI_SPDR);
619
620 if (rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE) < 0) {
621 dev_err(&rspi->master->dev,
622 "%s: receive timeout\n", __func__);
623 return -ETIMEDOUT;
624 }
625 /* SPDR allows 8, 16 or 32-bit access */
626 *data++ = rspi_read8(rspi, RSPI_SPDR);
627 remain--;
628 }
629
630 return 0;
631 }
632
633 #define receive_pio(spi, mesg, t) spi->ops->receive_pio(spi, mesg, t)
634
635 static int rspi_receive_dma(struct rspi_data *rspi, struct spi_transfer *t)
636 {
637 struct scatterlist sg, sg_dummy;
638 void *dummy = NULL, *rx_buf = NULL;
639 struct dma_async_tx_descriptor *desc, *desc_dummy;
640 unsigned len;
641 int ret = 0;
642
643 if (rspi->dma_width_16bit) {
644 /*
645 * If DMAC bus width is 16-bit, the driver allocates a dummy
646 * buffer. And, finally the driver converts the DMAC data into
647 * actual data as the following format:
648 * DMAC data: 1st byte, dummy, 2nd byte, dummy ...
649 * actual data: 1st byte, 2nd byte ...
650 */
651 len = t->len * 2;
652 rx_buf = kmalloc(len, GFP_KERNEL);
653 if (!rx_buf)
654 return -ENOMEM;
655 } else {
656 len = t->len;
657 rx_buf = t->rx_buf;
658 }
659
660 /* prepare dummy transfer to generate SPI clocks */
661 dummy = kzalloc(len, GFP_KERNEL);
662 if (!dummy) {
663 ret = -ENOMEM;
664 goto end_nomap;
665 }
666 if (!rspi_dma_map_sg(&sg_dummy, dummy, len, rspi->chan_tx,
667 DMA_TO_DEVICE)) {
668 ret = -EFAULT;
669 goto end_nomap;
670 }
671 desc_dummy = dmaengine_prep_slave_sg(rspi->chan_tx, &sg_dummy, 1,
672 DMA_TO_DEVICE, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
673 if (!desc_dummy) {
674 ret = -EIO;
675 goto end_dummy_mapped;
676 }
677
678 /* prepare receive transfer */
679 if (!rspi_dma_map_sg(&sg, rx_buf, len, rspi->chan_rx,
680 DMA_FROM_DEVICE)) {
681 ret = -EFAULT;
682 goto end_dummy_mapped;
683
684 }
685 desc = dmaengine_prep_slave_sg(rspi->chan_rx, &sg, 1, DMA_FROM_DEVICE,
686 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
687 if (!desc) {
688 ret = -EIO;
689 goto end;
690 }
691
692 rspi_receive_init(rspi);
693
694 /*
695 * DMAC needs SPTIE, but if SPTIE is set, this IRQ routine will be
696 * called. So, this driver disables the IRQ while DMA transfer.
697 */
698 disable_irq(rspi->irq);
699
700 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_TXMD, RSPI_SPCR);
701 rspi_enable_irq(rspi, SPCR_SPTIE | SPCR_SPRIE);
702 rspi->dma_callbacked = 0;
703
704 desc->callback = rspi_dma_complete;
705 desc->callback_param = rspi;
706 dmaengine_submit(desc);
707 dma_async_issue_pending(rspi->chan_rx);
708
709 desc_dummy->callback = NULL; /* No callback */
710 dmaengine_submit(desc_dummy);
711 dma_async_issue_pending(rspi->chan_tx);
712
713 ret = wait_event_interruptible_timeout(rspi->wait,
714 rspi->dma_callbacked, HZ);
715 if (ret > 0 && rspi->dma_callbacked)
716 ret = 0;
717 else if (!ret)
718 ret = -ETIMEDOUT;
719 rspi_disable_irq(rspi, SPCR_SPTIE | SPCR_SPRIE);
720
721 enable_irq(rspi->irq);
722
723 end:
724 rspi_dma_unmap_sg(&sg, rspi->chan_rx, DMA_FROM_DEVICE);
725 end_dummy_mapped:
726 rspi_dma_unmap_sg(&sg_dummy, rspi->chan_tx, DMA_TO_DEVICE);
727 end_nomap:
728 if (rspi->dma_width_16bit) {
729 if (!ret)
730 rspi_memory_from_8bit(t->rx_buf, rx_buf, t->len);
731 kfree(rx_buf);
732 }
733 kfree(dummy);
734
735 return ret;
736 }
737
738 static int rspi_is_dma(const struct rspi_data *rspi, struct spi_transfer *t)
739 {
740 if (t->tx_buf && rspi->chan_tx)
741 return 1;
742 /* If the module receives data by DMAC, it also needs TX DMAC */
743 if (t->rx_buf && rspi->chan_tx && rspi->chan_rx)
744 return 1;
745
746 return 0;
747 }
748
749 static void rspi_work(struct work_struct *work)
750 {
751 struct rspi_data *rspi = container_of(work, struct rspi_data, ws);
752 struct spi_message *mesg;
753 struct spi_transfer *t;
754 unsigned long flags;
755 int ret;
756
757 while (1) {
758 spin_lock_irqsave(&rspi->lock, flags);
759 if (list_empty(&rspi->queue)) {
760 spin_unlock_irqrestore(&rspi->lock, flags);
761 break;
762 }
763 mesg = list_entry(rspi->queue.next, struct spi_message, queue);
764 list_del_init(&mesg->queue);
765 spin_unlock_irqrestore(&rspi->lock, flags);
766
767 rspi_assert_ssl(rspi);
768
769 list_for_each_entry(t, &mesg->transfers, transfer_list) {
770 if (t->tx_buf) {
771 if (rspi_is_dma(rspi, t))
772 ret = rspi_send_dma(rspi, t);
773 else
774 ret = send_pio(rspi, mesg, t);
775 if (ret < 0)
776 goto error;
777 }
778 if (t->rx_buf) {
779 if (rspi_is_dma(rspi, t))
780 ret = rspi_receive_dma(rspi, t);
781 else
782 ret = receive_pio(rspi, mesg, t);
783 if (ret < 0)
784 goto error;
785 }
786 mesg->actual_length += t->len;
787 }
788 rspi_negate_ssl(rspi);
789
790 mesg->status = 0;
791 mesg->complete(mesg->context);
792 }
793
794 return;
795
796 error:
797 mesg->status = ret;
798 mesg->complete(mesg->context);
799 }
800
801 static int rspi_setup(struct spi_device *spi)
802 {
803 struct rspi_data *rspi = spi_master_get_devdata(spi->master);
804
805 rspi->max_speed_hz = spi->max_speed_hz;
806
807 rspi->spcmd = SPCMD_SSLKP;
808 if (spi->mode & SPI_CPOL)
809 rspi->spcmd |= SPCMD_CPOL;
810 if (spi->mode & SPI_CPHA)
811 rspi->spcmd |= SPCMD_CPHA;
812
813 set_config_register(rspi, 8);
814
815 return 0;
816 }
817
818 static int rspi_transfer(struct spi_device *spi, struct spi_message *mesg)
819 {
820 struct rspi_data *rspi = spi_master_get_devdata(spi->master);
821 unsigned long flags;
822
823 mesg->actual_length = 0;
824 mesg->status = -EINPROGRESS;
825
826 spin_lock_irqsave(&rspi->lock, flags);
827 list_add_tail(&mesg->queue, &rspi->queue);
828 schedule_work(&rspi->ws);
829 spin_unlock_irqrestore(&rspi->lock, flags);
830
831 return 0;
832 }
833
834 static void rspi_cleanup(struct spi_device *spi)
835 {
836 }
837
838 static irqreturn_t rspi_irq(int irq, void *_sr)
839 {
840 struct rspi_data *rspi = _sr;
841 u8 spsr;
842 irqreturn_t ret = IRQ_NONE;
843 u8 disable_irq = 0;
844
845 rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
846 if (spsr & SPSR_SPRF)
847 disable_irq |= SPCR_SPRIE;
848 if (spsr & SPSR_SPTEF)
849 disable_irq |= SPCR_SPTIE;
850
851 if (disable_irq) {
852 ret = IRQ_HANDLED;
853 rspi_disable_irq(rspi, disable_irq);
854 wake_up(&rspi->wait);
855 }
856
857 return ret;
858 }
859
860 static int rspi_request_dma(struct rspi_data *rspi,
861 struct platform_device *pdev)
862 {
863 const struct rspi_plat_data *rspi_pd = dev_get_platdata(&pdev->dev);
864 struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
865 dma_cap_mask_t mask;
866 struct dma_slave_config cfg;
867 int ret;
868
869 if (!res || !rspi_pd)
870 return 0; /* The driver assumes no error. */
871
872 rspi->dma_width_16bit = rspi_pd->dma_width_16bit;
873
874 /* If the module receives data by DMAC, it also needs TX DMAC */
875 if (rspi_pd->dma_rx_id && rspi_pd->dma_tx_id) {
876 dma_cap_zero(mask);
877 dma_cap_set(DMA_SLAVE, mask);
878 rspi->chan_rx = dma_request_channel(mask, shdma_chan_filter,
879 (void *)rspi_pd->dma_rx_id);
880 if (rspi->chan_rx) {
881 cfg.slave_id = rspi_pd->dma_rx_id;
882 cfg.direction = DMA_DEV_TO_MEM;
883 cfg.dst_addr = 0;
884 cfg.src_addr = res->start + RSPI_SPDR;
885 ret = dmaengine_slave_config(rspi->chan_rx, &cfg);
886 if (!ret)
887 dev_info(&pdev->dev, "Use DMA when rx.\n");
888 else
889 return ret;
890 }
891 }
892 if (rspi_pd->dma_tx_id) {
893 dma_cap_zero(mask);
894 dma_cap_set(DMA_SLAVE, mask);
895 rspi->chan_tx = dma_request_channel(mask, shdma_chan_filter,
896 (void *)rspi_pd->dma_tx_id);
897 if (rspi->chan_tx) {
898 cfg.slave_id = rspi_pd->dma_tx_id;
899 cfg.direction = DMA_MEM_TO_DEV;
900 cfg.dst_addr = res->start + RSPI_SPDR;
901 cfg.src_addr = 0;
902 ret = dmaengine_slave_config(rspi->chan_tx, &cfg);
903 if (!ret)
904 dev_info(&pdev->dev, "Use DMA when tx\n");
905 else
906 return ret;
907 }
908 }
909
910 return 0;
911 }
912
913 static void rspi_release_dma(struct rspi_data *rspi)
914 {
915 if (rspi->chan_tx)
916 dma_release_channel(rspi->chan_tx);
917 if (rspi->chan_rx)
918 dma_release_channel(rspi->chan_rx);
919 }
920
921 static int rspi_remove(struct platform_device *pdev)
922 {
923 struct rspi_data *rspi = platform_get_drvdata(pdev);
924
925 rspi_release_dma(rspi);
926 clk_disable(rspi->clk);
927
928 return 0;
929 }
930
931 static int rspi_probe(struct platform_device *pdev)
932 {
933 struct resource *res;
934 struct spi_master *master;
935 struct rspi_data *rspi;
936 int ret, irq;
937 char clk_name[16];
938 const struct rspi_plat_data *rspi_pd = dev_get_platdata(&pdev->dev);
939 const struct spi_ops *ops;
940 const struct platform_device_id *id_entry = pdev->id_entry;
941
942 ops = (struct spi_ops *)id_entry->driver_data;
943 /* ops parameter check */
944 if (!ops->set_config_register) {
945 dev_err(&pdev->dev, "there is no set_config_register\n");
946 return -ENODEV;
947 }
948
949 irq = platform_get_irq(pdev, 0);
950 if (irq < 0) {
951 dev_err(&pdev->dev, "platform_get_irq error\n");
952 return -ENODEV;
953 }
954
955 master = spi_alloc_master(&pdev->dev, sizeof(struct rspi_data));
956 if (master == NULL) {
957 dev_err(&pdev->dev, "spi_alloc_master error.\n");
958 return -ENOMEM;
959 }
960
961 rspi = spi_master_get_devdata(master);
962 platform_set_drvdata(pdev, rspi);
963 rspi->ops = ops;
964 rspi->master = master;
965
966 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
967 rspi->addr = devm_ioremap_resource(&pdev->dev, res);
968 if (IS_ERR(rspi->addr)) {
969 ret = PTR_ERR(rspi->addr);
970 goto error1;
971 }
972
973 snprintf(clk_name, sizeof(clk_name), "%s%d", id_entry->name, pdev->id);
974 rspi->clk = devm_clk_get(&pdev->dev, clk_name);
975 if (IS_ERR(rspi->clk)) {
976 dev_err(&pdev->dev, "cannot get clock\n");
977 ret = PTR_ERR(rspi->clk);
978 goto error1;
979 }
980 clk_enable(rspi->clk);
981
982 INIT_LIST_HEAD(&rspi->queue);
983 spin_lock_init(&rspi->lock);
984 INIT_WORK(&rspi->ws, rspi_work);
985 init_waitqueue_head(&rspi->wait);
986
987 if (rspi_pd && rspi_pd->num_chipselect)
988 master->num_chipselect = rspi_pd->num_chipselect;
989 else
990 master->num_chipselect = 2; /* default */
991
992 master->bus_num = pdev->id;
993 master->setup = rspi_setup;
994 master->transfer = rspi_transfer;
995 master->cleanup = rspi_cleanup;
996 master->mode_bits = SPI_CPHA | SPI_CPOL;
997
998 ret = devm_request_irq(&pdev->dev, irq, rspi_irq, 0,
999 dev_name(&pdev->dev), rspi);
1000 if (ret < 0) {
1001 dev_err(&pdev->dev, "request_irq error\n");
1002 goto error2;
1003 }
1004
1005 rspi->irq = irq;
1006 ret = rspi_request_dma(rspi, pdev);
1007 if (ret < 0) {
1008 dev_err(&pdev->dev, "rspi_request_dma failed.\n");
1009 goto error3;
1010 }
1011
1012 ret = devm_spi_register_master(&pdev->dev, master);
1013 if (ret < 0) {
1014 dev_err(&pdev->dev, "spi_register_master error.\n");
1015 goto error3;
1016 }
1017
1018 dev_info(&pdev->dev, "probed\n");
1019
1020 return 0;
1021
1022 error3:
1023 rspi_release_dma(rspi);
1024 error2:
1025 clk_disable(rspi->clk);
1026 error1:
1027 spi_master_put(master);
1028
1029 return ret;
1030 }
1031
1032 static struct spi_ops rspi_ops = {
1033 .set_config_register = rspi_set_config_register,
1034 .send_pio = rspi_send_pio,
1035 .receive_pio = rspi_receive_pio,
1036 };
1037
1038 static struct spi_ops qspi_ops = {
1039 .set_config_register = qspi_set_config_register,
1040 .send_pio = qspi_send_pio,
1041 .receive_pio = qspi_receive_pio,
1042 };
1043
1044 static struct platform_device_id spi_driver_ids[] = {
1045 { "rspi", (kernel_ulong_t)&rspi_ops },
1046 { "qspi", (kernel_ulong_t)&qspi_ops },
1047 {},
1048 };
1049
1050 MODULE_DEVICE_TABLE(platform, spi_driver_ids);
1051
1052 static struct platform_driver rspi_driver = {
1053 .probe = rspi_probe,
1054 .remove = rspi_remove,
1055 .id_table = spi_driver_ids,
1056 .driver = {
1057 .name = "renesas_spi",
1058 .owner = THIS_MODULE,
1059 },
1060 };
1061 module_platform_driver(rspi_driver);
1062
1063 MODULE_DESCRIPTION("Renesas RSPI bus driver");
1064 MODULE_LICENSE("GPL v2");
1065 MODULE_AUTHOR("Yoshihiro Shimoda");
1066 MODULE_ALIAS("platform:rspi");
Linux with added FPC-III support