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Merge remote-tracking branch 'spi/topic/tle62x0' into spi-next
[deliverable/linux.git] / drivers / spi / spi-ti-qspi.c
1 /*
2 * TI QSPI driver
3 *
4 * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com
5 * Author: Sourav Poddar <sourav.poddar@ti.com>
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GPLv2.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR /PURPOSE. See the
13 * GNU General Public License for more details.
14 */
15
16 #include <linux/kernel.h>
17 #include <linux/init.h>
18 #include <linux/interrupt.h>
19 #include <linux/module.h>
20 #include <linux/device.h>
21 #include <linux/delay.h>
22 #include <linux/dma-mapping.h>
23 #include <linux/dmaengine.h>
24 #include <linux/omap-dma.h>
25 #include <linux/platform_device.h>
26 #include <linux/err.h>
27 #include <linux/clk.h>
28 #include <linux/io.h>
29 #include <linux/slab.h>
30 #include <linux/pm_runtime.h>
31 #include <linux/of.h>
32 #include <linux/of_device.h>
33 #include <linux/pinctrl/consumer.h>
34
35 #include <linux/spi/spi.h>
36
37 struct ti_qspi_regs {
38 u32 clkctrl;
39 };
40
41 struct ti_qspi {
42 struct completion transfer_complete;
43
44 /* IRQ synchronization */
45 spinlock_t lock;
46
47 /* list synchronization */
48 struct mutex list_lock;
49
50 struct spi_master *master;
51 void __iomem *base;
52 struct clk *fclk;
53 struct device *dev;
54
55 struct ti_qspi_regs ctx_reg;
56
57 u32 spi_max_frequency;
58 u32 cmd;
59 u32 dc;
60 u32 stat;
61 };
62
63 #define QSPI_PID (0x0)
64 #define QSPI_SYSCONFIG (0x10)
65 #define QSPI_INTR_STATUS_RAW_SET (0x20)
66 #define QSPI_INTR_STATUS_ENABLED_CLEAR (0x24)
67 #define QSPI_INTR_ENABLE_SET_REG (0x28)
68 #define QSPI_INTR_ENABLE_CLEAR_REG (0x2c)
69 #define QSPI_SPI_CLOCK_CNTRL_REG (0x40)
70 #define QSPI_SPI_DC_REG (0x44)
71 #define QSPI_SPI_CMD_REG (0x48)
72 #define QSPI_SPI_STATUS_REG (0x4c)
73 #define QSPI_SPI_DATA_REG (0x50)
74 #define QSPI_SPI_SETUP0_REG (0x54)
75 #define QSPI_SPI_SWITCH_REG (0x64)
76 #define QSPI_SPI_SETUP1_REG (0x58)
77 #define QSPI_SPI_SETUP2_REG (0x5c)
78 #define QSPI_SPI_SETUP3_REG (0x60)
79 #define QSPI_SPI_DATA_REG_1 (0x68)
80 #define QSPI_SPI_DATA_REG_2 (0x6c)
81 #define QSPI_SPI_DATA_REG_3 (0x70)
82
83 #define QSPI_COMPLETION_TIMEOUT msecs_to_jiffies(2000)
84
85 #define QSPI_FCLK 192000000
86
87 /* Clock Control */
88 #define QSPI_CLK_EN (1 << 31)
89 #define QSPI_CLK_DIV_MAX 0xffff
90
91 /* Command */
92 #define QSPI_EN_CS(n) (n << 28)
93 #define QSPI_WLEN(n) ((n - 1) << 19)
94 #define QSPI_3_PIN (1 << 18)
95 #define QSPI_RD_SNGL (1 << 16)
96 #define QSPI_WR_SNGL (2 << 16)
97 #define QSPI_RD_DUAL (3 << 16)
98 #define QSPI_RD_QUAD (7 << 16)
99 #define QSPI_INVAL (4 << 16)
100 #define QSPI_WC_CMD_INT_EN (1 << 14)
101 #define QSPI_FLEN(n) ((n - 1) << 0)
102
103 /* STATUS REGISTER */
104 #define WC 0x02
105
106 /* INTERRUPT REGISTER */
107 #define QSPI_WC_INT_EN (1 << 1)
108 #define QSPI_WC_INT_DISABLE (1 << 1)
109
110 /* Device Control */
111 #define QSPI_DD(m, n) (m << (3 + n * 8))
112 #define QSPI_CKPHA(n) (1 << (2 + n * 8))
113 #define QSPI_CSPOL(n) (1 << (1 + n * 8))
114 #define QSPI_CKPOL(n) (1 << (n * 8))
115
116 #define QSPI_FRAME 4096
117
118 #define QSPI_AUTOSUSPEND_TIMEOUT 2000
119
120 static inline unsigned long ti_qspi_read(struct ti_qspi *qspi,
121 unsigned long reg)
122 {
123 return readl(qspi->base + reg);
124 }
125
126 static inline void ti_qspi_write(struct ti_qspi *qspi,
127 unsigned long val, unsigned long reg)
128 {
129 writel(val, qspi->base + reg);
130 }
131
132 static int ti_qspi_setup(struct spi_device *spi)
133 {
134 struct ti_qspi *qspi = spi_master_get_devdata(spi->master);
135 struct ti_qspi_regs *ctx_reg = &qspi->ctx_reg;
136 int clk_div = 0, ret;
137 u32 clk_ctrl_reg, clk_rate, clk_mask;
138
139 if (spi->master->busy) {
140 dev_dbg(qspi->dev, "master busy doing other trasnfers\n");
141 return -EBUSY;
142 }
143
144 if (!qspi->spi_max_frequency) {
145 dev_err(qspi->dev, "spi max frequency not defined\n");
146 return -EINVAL;
147 }
148
149 clk_rate = clk_get_rate(qspi->fclk);
150
151 clk_div = DIV_ROUND_UP(clk_rate, qspi->spi_max_frequency) - 1;
152
153 if (clk_div < 0) {
154 dev_dbg(qspi->dev, "clock divider < 0, using /1 divider\n");
155 return -EINVAL;
156 }
157
158 if (clk_div > QSPI_CLK_DIV_MAX) {
159 dev_dbg(qspi->dev, "clock divider >%d , using /%d divider\n",
160 QSPI_CLK_DIV_MAX, QSPI_CLK_DIV_MAX + 1);
161 return -EINVAL;
162 }
163
164 dev_dbg(qspi->dev, "hz: %d, clock divider %d\n",
165 qspi->spi_max_frequency, clk_div);
166
167 ret = pm_runtime_get_sync(qspi->dev);
168 if (ret) {
169 dev_err(qspi->dev, "pm_runtime_get_sync() failed\n");
170 return ret;
171 }
172
173 clk_ctrl_reg = ti_qspi_read(qspi, QSPI_SPI_CLOCK_CNTRL_REG);
174
175 clk_ctrl_reg &= ~QSPI_CLK_EN;
176
177 /* disable SCLK */
178 ti_qspi_write(qspi, clk_ctrl_reg, QSPI_SPI_CLOCK_CNTRL_REG);
179
180 /* enable SCLK */
181 clk_mask = QSPI_CLK_EN | clk_div;
182 ti_qspi_write(qspi, clk_mask, QSPI_SPI_CLOCK_CNTRL_REG);
183 ctx_reg->clkctrl = clk_mask;
184
185 pm_runtime_mark_last_busy(qspi->dev);
186 ret = pm_runtime_put_autosuspend(qspi->dev);
187 if (ret < 0) {
188 dev_err(qspi->dev, "pm_runtime_put_autosuspend() failed\n");
189 return ret;
190 }
191
192 return 0;
193 }
194
195 static void ti_qspi_restore_ctx(struct ti_qspi *qspi)
196 {
197 struct ti_qspi_regs *ctx_reg = &qspi->ctx_reg;
198
199 ti_qspi_write(qspi, ctx_reg->clkctrl, QSPI_SPI_CLOCK_CNTRL_REG);
200 }
201
202 static int qspi_write_msg(struct ti_qspi *qspi, struct spi_transfer *t)
203 {
204 int wlen, count, ret;
205 unsigned int cmd;
206 const u8 *txbuf;
207
208 txbuf = t->tx_buf;
209 cmd = qspi->cmd | QSPI_WR_SNGL;
210 count = t->len;
211 wlen = t->bits_per_word;
212
213 while (count) {
214 switch (wlen) {
215 case 8:
216 dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %02x\n",
217 cmd, qspi->dc, *txbuf);
218 writeb(*txbuf, qspi->base + QSPI_SPI_DATA_REG);
219 ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG);
220 ret = wait_for_completion_timeout(&qspi->transfer_complete,
221 QSPI_COMPLETION_TIMEOUT);
222 if (ret == 0) {
223 dev_err(qspi->dev, "write timed out\n");
224 return -ETIMEDOUT;
225 }
226 txbuf += 1;
227 count -= 1;
228 break;
229 case 16:
230 dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %04x\n",
231 cmd, qspi->dc, *txbuf);
232 writew(*((u16 *)txbuf), qspi->base + QSPI_SPI_DATA_REG);
233 ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG);
234 ret = wait_for_completion_timeout(&qspi->transfer_complete,
235 QSPI_COMPLETION_TIMEOUT);
236 if (ret == 0) {
237 dev_err(qspi->dev, "write timed out\n");
238 return -ETIMEDOUT;
239 }
240 txbuf += 2;
241 count -= 2;
242 break;
243 case 32:
244 dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %08x\n",
245 cmd, qspi->dc, *txbuf);
246 writel(*((u32 *)txbuf), qspi->base + QSPI_SPI_DATA_REG);
247 ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG);
248 ret = wait_for_completion_timeout(&qspi->transfer_complete,
249 QSPI_COMPLETION_TIMEOUT);
250 if (ret == 0) {
251 dev_err(qspi->dev, "write timed out\n");
252 return -ETIMEDOUT;
253 }
254 txbuf += 4;
255 count -= 4;
256 break;
257 }
258 }
259
260 return 0;
261 }
262
263 static int qspi_read_msg(struct ti_qspi *qspi, struct spi_transfer *t)
264 {
265 int wlen, count, ret;
266 unsigned int cmd;
267 u8 *rxbuf;
268
269 rxbuf = t->rx_buf;
270 cmd = qspi->cmd;
271 switch (t->rx_nbits) {
272 case SPI_NBITS_DUAL:
273 cmd |= QSPI_RD_DUAL;
274 break;
275 case SPI_NBITS_QUAD:
276 cmd |= QSPI_RD_QUAD;
277 break;
278 default:
279 cmd |= QSPI_RD_SNGL;
280 break;
281 }
282 count = t->len;
283 wlen = t->bits_per_word;
284
285 while (count) {
286 dev_dbg(qspi->dev, "rx cmd %08x dc %08x\n", cmd, qspi->dc);
287 ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG);
288 ret = wait_for_completion_timeout(&qspi->transfer_complete,
289 QSPI_COMPLETION_TIMEOUT);
290 if (ret == 0) {
291 dev_err(qspi->dev, "read timed out\n");
292 return -ETIMEDOUT;
293 }
294 switch (wlen) {
295 case 8:
296 *rxbuf = readb(qspi->base + QSPI_SPI_DATA_REG);
297 rxbuf += 1;
298 count -= 1;
299 break;
300 case 16:
301 *((u16 *)rxbuf) = readw(qspi->base + QSPI_SPI_DATA_REG);
302 rxbuf += 2;
303 count -= 2;
304 break;
305 case 32:
306 *((u32 *)rxbuf) = readl(qspi->base + QSPI_SPI_DATA_REG);
307 rxbuf += 4;
308 count -= 4;
309 break;
310 }
311 }
312
313 return 0;
314 }
315
316 static int qspi_transfer_msg(struct ti_qspi *qspi, struct spi_transfer *t)
317 {
318 int ret;
319
320 if (t->tx_buf) {
321 ret = qspi_write_msg(qspi, t);
322 if (ret) {
323 dev_dbg(qspi->dev, "Error while writing\n");
324 return ret;
325 }
326 }
327
328 if (t->rx_buf) {
329 ret = qspi_read_msg(qspi, t);
330 if (ret) {
331 dev_dbg(qspi->dev, "Error while reading\n");
332 return ret;
333 }
334 }
335
336 return 0;
337 }
338
339 static int ti_qspi_start_transfer_one(struct spi_master *master,
340 struct spi_message *m)
341 {
342 struct ti_qspi *qspi = spi_master_get_devdata(master);
343 struct spi_device *spi = m->spi;
344 struct spi_transfer *t;
345 int status = 0, ret;
346 int frame_length;
347
348 /* setup device control reg */
349 qspi->dc = 0;
350
351 if (spi->mode & SPI_CPHA)
352 qspi->dc |= QSPI_CKPHA(spi->chip_select);
353 if (spi->mode & SPI_CPOL)
354 qspi->dc |= QSPI_CKPOL(spi->chip_select);
355 if (spi->mode & SPI_CS_HIGH)
356 qspi->dc |= QSPI_CSPOL(spi->chip_select);
357
358 frame_length = (m->frame_length << 3) / spi->bits_per_word;
359
360 frame_length = clamp(frame_length, 0, QSPI_FRAME);
361
362 /* setup command reg */
363 qspi->cmd = 0;
364 qspi->cmd |= QSPI_EN_CS(spi->chip_select);
365 qspi->cmd |= QSPI_FLEN(frame_length);
366 qspi->cmd |= QSPI_WC_CMD_INT_EN;
367
368 ti_qspi_write(qspi, QSPI_WC_INT_EN, QSPI_INTR_ENABLE_SET_REG);
369 ti_qspi_write(qspi, qspi->dc, QSPI_SPI_DC_REG);
370
371 mutex_lock(&qspi->list_lock);
372
373 list_for_each_entry(t, &m->transfers, transfer_list) {
374 qspi->cmd |= QSPI_WLEN(t->bits_per_word);
375
376 ret = qspi_transfer_msg(qspi, t);
377 if (ret) {
378 dev_dbg(qspi->dev, "transfer message failed\n");
379 mutex_unlock(&qspi->list_lock);
380 return -EINVAL;
381 }
382
383 m->actual_length += t->len;
384 }
385
386 mutex_unlock(&qspi->list_lock);
387
388 m->status = status;
389 spi_finalize_current_message(master);
390
391 ti_qspi_write(qspi, qspi->cmd | QSPI_INVAL, QSPI_SPI_CMD_REG);
392
393 return status;
394 }
395
396 static irqreturn_t ti_qspi_isr(int irq, void *dev_id)
397 {
398 struct ti_qspi *qspi = dev_id;
399 u16 int_stat;
400
401 irqreturn_t ret = IRQ_HANDLED;
402
403 spin_lock(&qspi->lock);
404
405 int_stat = ti_qspi_read(qspi, QSPI_INTR_STATUS_ENABLED_CLEAR);
406 qspi->stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
407
408 if (!int_stat) {
409 dev_dbg(qspi->dev, "No IRQ triggered\n");
410 ret = IRQ_NONE;
411 goto out;
412 }
413
414 ret = IRQ_WAKE_THREAD;
415
416 ti_qspi_write(qspi, QSPI_WC_INT_DISABLE, QSPI_INTR_ENABLE_CLEAR_REG);
417 ti_qspi_write(qspi, QSPI_WC_INT_DISABLE,
418 QSPI_INTR_STATUS_ENABLED_CLEAR);
419
420 out:
421 spin_unlock(&qspi->lock);
422
423 return ret;
424 }
425
426 static irqreturn_t ti_qspi_threaded_isr(int this_irq, void *dev_id)
427 {
428 struct ti_qspi *qspi = dev_id;
429 unsigned long flags;
430
431 spin_lock_irqsave(&qspi->lock, flags);
432
433 if (qspi->stat & WC)
434 complete(&qspi->transfer_complete);
435
436 spin_unlock_irqrestore(&qspi->lock, flags);
437
438 ti_qspi_write(qspi, QSPI_WC_INT_EN, QSPI_INTR_ENABLE_SET_REG);
439
440 return IRQ_HANDLED;
441 }
442
443 static int ti_qspi_runtime_resume(struct device *dev)
444 {
445 struct ti_qspi *qspi;
446 struct spi_master *master;
447
448 master = dev_get_drvdata(dev);
449 qspi = spi_master_get_devdata(master);
450 ti_qspi_restore_ctx(qspi);
451
452 return 0;
453 }
454
455 static const struct of_device_id ti_qspi_match[] = {
456 {.compatible = "ti,dra7xxx-qspi" },
457 {.compatible = "ti,am4372-qspi" },
458 {},
459 };
460 MODULE_DEVICE_TABLE(of, ti_qspi_match);
461
462 static int ti_qspi_probe(struct platform_device *pdev)
463 {
464 struct ti_qspi *qspi;
465 struct spi_master *master;
466 struct resource *r;
467 struct device_node *np = pdev->dev.of_node;
468 u32 max_freq;
469 int ret = 0, num_cs, irq;
470
471 master = spi_alloc_master(&pdev->dev, sizeof(*qspi));
472 if (!master)
473 return -ENOMEM;
474
475 master->mode_bits = SPI_CPOL | SPI_CPHA;
476
477 master->bus_num = -1;
478 master->flags = SPI_MASTER_HALF_DUPLEX;
479 master->setup = ti_qspi_setup;
480 master->auto_runtime_pm = true;
481 master->transfer_one_message = ti_qspi_start_transfer_one;
482 master->dev.of_node = pdev->dev.of_node;
483 master->bits_per_word_mask = BIT(32 - 1) | BIT(16 - 1) | BIT(8 - 1);
484
485 if (!of_property_read_u32(np, "num-cs", &num_cs))
486 master->num_chipselect = num_cs;
487
488 platform_set_drvdata(pdev, master);
489
490 qspi = spi_master_get_devdata(master);
491 qspi->master = master;
492 qspi->dev = &pdev->dev;
493
494 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
495
496 irq = platform_get_irq(pdev, 0);
497 if (irq < 0) {
498 dev_err(&pdev->dev, "no irq resource?\n");
499 return irq;
500 }
501
502 spin_lock_init(&qspi->lock);
503 mutex_init(&qspi->list_lock);
504
505 qspi->base = devm_ioremap_resource(&pdev->dev, r);
506 if (IS_ERR(qspi->base)) {
507 ret = PTR_ERR(qspi->base);
508 goto free_master;
509 }
510
511 ret = devm_request_threaded_irq(&pdev->dev, irq, ti_qspi_isr,
512 ti_qspi_threaded_isr, 0,
513 dev_name(&pdev->dev), qspi);
514 if (ret < 0) {
515 dev_err(&pdev->dev, "Failed to register ISR for IRQ %d\n",
516 irq);
517 goto free_master;
518 }
519
520 qspi->fclk = devm_clk_get(&pdev->dev, "fck");
521 if (IS_ERR(qspi->fclk)) {
522 ret = PTR_ERR(qspi->fclk);
523 dev_err(&pdev->dev, "could not get clk: %d\n", ret);
524 }
525
526 init_completion(&qspi->transfer_complete);
527
528 pm_runtime_use_autosuspend(&pdev->dev);
529 pm_runtime_set_autosuspend_delay(&pdev->dev, QSPI_AUTOSUSPEND_TIMEOUT);
530 pm_runtime_enable(&pdev->dev);
531
532 if (!of_property_read_u32(np, "spi-max-frequency", &max_freq))
533 qspi->spi_max_frequency = max_freq;
534
535 ret = spi_register_master(master);
536 if (ret)
537 goto free_master;
538
539 return 0;
540
541 free_master:
542 spi_master_put(master);
543 return ret;
544 }
545
546 static int ti_qspi_remove(struct platform_device *pdev)
547 {
548 struct ti_qspi *qspi = platform_get_drvdata(pdev);
549
550 spi_unregister_master(qspi->master);
551
552 return 0;
553 }
554
555 static const struct dev_pm_ops ti_qspi_pm_ops = {
556 .runtime_resume = ti_qspi_runtime_resume,
557 };
558
559 static struct platform_driver ti_qspi_driver = {
560 .probe = ti_qspi_probe,
561 .remove = ti_qspi_remove,
562 .driver = {
563 .name = "ti,dra7xxx-qspi",
564 .owner = THIS_MODULE,
565 .pm = &ti_qspi_pm_ops,
566 .of_match_table = ti_qspi_match,
567 }
568 };
569
570 module_platform_driver(ti_qspi_driver);
571
572 MODULE_AUTHOR("Sourav Poddar <sourav.poddar@ti.com>");
573 MODULE_LICENSE("GPL v2");
574 MODULE_DESCRIPTION("TI QSPI controller driver");
Linux kernel - Deliverables
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