xref: /linux/drivers/spi/spi-ti-qspi.c (revision 110e6f26af80dfd90b6e5c645b1aed7228aa580d)
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 #include <linux/mfd/syscon.h>
35 #include <linux/regmap.h>
36 
37 #include <linux/spi/spi.h>
38 
39 struct ti_qspi_regs {
40 	u32 clkctrl;
41 };
42 
43 struct ti_qspi {
44 	/* list synchronization */
45 	struct mutex            list_lock;
46 
47 	struct spi_master	*master;
48 	void __iomem            *base;
49 	void __iomem            *mmap_base;
50 	struct regmap		*ctrl_base;
51 	unsigned int		ctrl_reg;
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 
61 	bool mmap_enabled;
62 };
63 
64 #define QSPI_PID			(0x0)
65 #define QSPI_SYSCONFIG			(0x10)
66 #define QSPI_SPI_CLOCK_CNTRL_REG	(0x40)
67 #define QSPI_SPI_DC_REG			(0x44)
68 #define QSPI_SPI_CMD_REG		(0x48)
69 #define QSPI_SPI_STATUS_REG		(0x4c)
70 #define QSPI_SPI_DATA_REG		(0x50)
71 #define QSPI_SPI_SETUP_REG(n)		((0x54 + 4 * n))
72 #define QSPI_SPI_SWITCH_REG		(0x64)
73 #define QSPI_SPI_DATA_REG_1		(0x68)
74 #define QSPI_SPI_DATA_REG_2		(0x6c)
75 #define QSPI_SPI_DATA_REG_3		(0x70)
76 
77 #define QSPI_COMPLETION_TIMEOUT		msecs_to_jiffies(2000)
78 
79 #define QSPI_FCLK			192000000
80 
81 /* Clock Control */
82 #define QSPI_CLK_EN			(1 << 31)
83 #define QSPI_CLK_DIV_MAX		0xffff
84 
85 /* Command */
86 #define QSPI_EN_CS(n)			(n << 28)
87 #define QSPI_WLEN(n)			((n - 1) << 19)
88 #define QSPI_3_PIN			(1 << 18)
89 #define QSPI_RD_SNGL			(1 << 16)
90 #define QSPI_WR_SNGL			(2 << 16)
91 #define QSPI_RD_DUAL			(3 << 16)
92 #define QSPI_RD_QUAD			(7 << 16)
93 #define QSPI_INVAL			(4 << 16)
94 #define QSPI_FLEN(n)			((n - 1) << 0)
95 #define QSPI_WLEN_MAX_BITS		128
96 #define QSPI_WLEN_MAX_BYTES		16
97 
98 /* STATUS REGISTER */
99 #define BUSY				0x01
100 #define WC				0x02
101 
102 /* Device Control */
103 #define QSPI_DD(m, n)			(m << (3 + n * 8))
104 #define QSPI_CKPHA(n)			(1 << (2 + n * 8))
105 #define QSPI_CSPOL(n)			(1 << (1 + n * 8))
106 #define QSPI_CKPOL(n)			(1 << (n * 8))
107 
108 #define	QSPI_FRAME			4096
109 
110 #define QSPI_AUTOSUSPEND_TIMEOUT         2000
111 
112 #define MEM_CS_EN(n)			((n + 1) << 8)
113 #define MEM_CS_MASK			(7 << 8)
114 
115 #define MM_SWITCH			0x1
116 
117 #define QSPI_SETUP_RD_NORMAL		(0x0 << 12)
118 #define QSPI_SETUP_RD_DUAL		(0x1 << 12)
119 #define QSPI_SETUP_RD_QUAD		(0x3 << 12)
120 #define QSPI_SETUP_ADDR_SHIFT		8
121 #define QSPI_SETUP_DUMMY_SHIFT		10
122 
123 static inline unsigned long ti_qspi_read(struct ti_qspi *qspi,
124 		unsigned long reg)
125 {
126 	return readl(qspi->base + reg);
127 }
128 
129 static inline void ti_qspi_write(struct ti_qspi *qspi,
130 		unsigned long val, unsigned long reg)
131 {
132 	writel(val, qspi->base + reg);
133 }
134 
135 static int ti_qspi_setup(struct spi_device *spi)
136 {
137 	struct ti_qspi	*qspi = spi_master_get_devdata(spi->master);
138 	struct ti_qspi_regs *ctx_reg = &qspi->ctx_reg;
139 	int clk_div = 0, ret;
140 	u32 clk_ctrl_reg, clk_rate, clk_mask;
141 
142 	if (spi->master->busy) {
143 		dev_dbg(qspi->dev, "master busy doing other trasnfers\n");
144 		return -EBUSY;
145 	}
146 
147 	if (!qspi->spi_max_frequency) {
148 		dev_err(qspi->dev, "spi max frequency not defined\n");
149 		return -EINVAL;
150 	}
151 
152 	clk_rate = clk_get_rate(qspi->fclk);
153 
154 	clk_div = DIV_ROUND_UP(clk_rate, qspi->spi_max_frequency) - 1;
155 
156 	if (clk_div < 0) {
157 		dev_dbg(qspi->dev, "clock divider < 0, using /1 divider\n");
158 		return -EINVAL;
159 	}
160 
161 	if (clk_div > QSPI_CLK_DIV_MAX) {
162 		dev_dbg(qspi->dev, "clock divider >%d , using /%d divider\n",
163 				QSPI_CLK_DIV_MAX, QSPI_CLK_DIV_MAX + 1);
164 		return -EINVAL;
165 	}
166 
167 	dev_dbg(qspi->dev, "hz: %d, clock divider %d\n",
168 			qspi->spi_max_frequency, clk_div);
169 
170 	ret = pm_runtime_get_sync(qspi->dev);
171 	if (ret < 0) {
172 		dev_err(qspi->dev, "pm_runtime_get_sync() failed\n");
173 		return ret;
174 	}
175 
176 	clk_ctrl_reg = ti_qspi_read(qspi, QSPI_SPI_CLOCK_CNTRL_REG);
177 
178 	clk_ctrl_reg &= ~QSPI_CLK_EN;
179 
180 	/* disable SCLK */
181 	ti_qspi_write(qspi, clk_ctrl_reg, QSPI_SPI_CLOCK_CNTRL_REG);
182 
183 	/* enable SCLK */
184 	clk_mask = QSPI_CLK_EN | clk_div;
185 	ti_qspi_write(qspi, clk_mask, QSPI_SPI_CLOCK_CNTRL_REG);
186 	ctx_reg->clkctrl = clk_mask;
187 
188 	pm_runtime_mark_last_busy(qspi->dev);
189 	ret = pm_runtime_put_autosuspend(qspi->dev);
190 	if (ret < 0) {
191 		dev_err(qspi->dev, "pm_runtime_put_autosuspend() failed\n");
192 		return ret;
193 	}
194 
195 	return 0;
196 }
197 
198 static void ti_qspi_restore_ctx(struct ti_qspi *qspi)
199 {
200 	struct ti_qspi_regs *ctx_reg = &qspi->ctx_reg;
201 
202 	ti_qspi_write(qspi, ctx_reg->clkctrl, QSPI_SPI_CLOCK_CNTRL_REG);
203 }
204 
205 static inline u32 qspi_is_busy(struct ti_qspi *qspi)
206 {
207 	u32 stat;
208 	unsigned long timeout = jiffies + QSPI_COMPLETION_TIMEOUT;
209 
210 	stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
211 	while ((stat & BUSY) && time_after(timeout, jiffies)) {
212 		cpu_relax();
213 		stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
214 	}
215 
216 	WARN(stat & BUSY, "qspi busy\n");
217 	return stat & BUSY;
218 }
219 
220 static inline int ti_qspi_poll_wc(struct ti_qspi *qspi)
221 {
222 	u32 stat;
223 	unsigned long timeout = jiffies + QSPI_COMPLETION_TIMEOUT;
224 
225 	do {
226 		stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
227 		if (stat & WC)
228 			return 0;
229 		cpu_relax();
230 	} while (time_after(timeout, jiffies));
231 
232 	stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
233 	if (stat & WC)
234 		return 0;
235 	return  -ETIMEDOUT;
236 }
237 
238 static int qspi_write_msg(struct ti_qspi *qspi, struct spi_transfer *t)
239 {
240 	int wlen, count, xfer_len;
241 	unsigned int cmd;
242 	const u8 *txbuf;
243 	u32 data;
244 
245 	txbuf = t->tx_buf;
246 	cmd = qspi->cmd | QSPI_WR_SNGL;
247 	count = t->len;
248 	wlen = t->bits_per_word >> 3;	/* in bytes */
249 	xfer_len = wlen;
250 
251 	while (count) {
252 		if (qspi_is_busy(qspi))
253 			return -EBUSY;
254 
255 		switch (wlen) {
256 		case 1:
257 			dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %02x\n",
258 					cmd, qspi->dc, *txbuf);
259 			if (count >= QSPI_WLEN_MAX_BYTES) {
260 				u32 *txp = (u32 *)txbuf;
261 
262 				data = cpu_to_be32(*txp++);
263 				writel(data, qspi->base +
264 				       QSPI_SPI_DATA_REG_3);
265 				data = cpu_to_be32(*txp++);
266 				writel(data, qspi->base +
267 				       QSPI_SPI_DATA_REG_2);
268 				data = cpu_to_be32(*txp++);
269 				writel(data, qspi->base +
270 				       QSPI_SPI_DATA_REG_1);
271 				data = cpu_to_be32(*txp++);
272 				writel(data, qspi->base +
273 				       QSPI_SPI_DATA_REG);
274 				xfer_len = QSPI_WLEN_MAX_BYTES;
275 				cmd |= QSPI_WLEN(QSPI_WLEN_MAX_BITS);
276 			} else {
277 				writeb(*txbuf, qspi->base + QSPI_SPI_DATA_REG);
278 				cmd = qspi->cmd | QSPI_WR_SNGL;
279 				xfer_len = wlen;
280 				cmd |= QSPI_WLEN(wlen);
281 			}
282 			break;
283 		case 2:
284 			dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %04x\n",
285 					cmd, qspi->dc, *txbuf);
286 			writew(*((u16 *)txbuf), qspi->base + QSPI_SPI_DATA_REG);
287 			break;
288 		case 4:
289 			dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %08x\n",
290 					cmd, qspi->dc, *txbuf);
291 			writel(*((u32 *)txbuf), qspi->base + QSPI_SPI_DATA_REG);
292 			break;
293 		}
294 
295 		ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG);
296 		if (ti_qspi_poll_wc(qspi)) {
297 			dev_err(qspi->dev, "write timed out\n");
298 			return -ETIMEDOUT;
299 		}
300 		txbuf += xfer_len;
301 		count -= xfer_len;
302 	}
303 
304 	return 0;
305 }
306 
307 static int qspi_read_msg(struct ti_qspi *qspi, struct spi_transfer *t)
308 {
309 	int wlen, count;
310 	unsigned int cmd;
311 	u8 *rxbuf;
312 
313 	rxbuf = t->rx_buf;
314 	cmd = qspi->cmd;
315 	switch (t->rx_nbits) {
316 	case SPI_NBITS_DUAL:
317 		cmd |= QSPI_RD_DUAL;
318 		break;
319 	case SPI_NBITS_QUAD:
320 		cmd |= QSPI_RD_QUAD;
321 		break;
322 	default:
323 		cmd |= QSPI_RD_SNGL;
324 		break;
325 	}
326 	count = t->len;
327 	wlen = t->bits_per_word >> 3;	/* in bytes */
328 
329 	while (count) {
330 		dev_dbg(qspi->dev, "rx cmd %08x dc %08x\n", cmd, qspi->dc);
331 		if (qspi_is_busy(qspi))
332 			return -EBUSY;
333 
334 		ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG);
335 		if (ti_qspi_poll_wc(qspi)) {
336 			dev_err(qspi->dev, "read timed out\n");
337 			return -ETIMEDOUT;
338 		}
339 		switch (wlen) {
340 		case 1:
341 			*rxbuf = readb(qspi->base + QSPI_SPI_DATA_REG);
342 			break;
343 		case 2:
344 			*((u16 *)rxbuf) = readw(qspi->base + QSPI_SPI_DATA_REG);
345 			break;
346 		case 4:
347 			*((u32 *)rxbuf) = readl(qspi->base + QSPI_SPI_DATA_REG);
348 			break;
349 		}
350 		rxbuf += wlen;
351 		count -= wlen;
352 	}
353 
354 	return 0;
355 }
356 
357 static int qspi_transfer_msg(struct ti_qspi *qspi, struct spi_transfer *t)
358 {
359 	int ret;
360 
361 	if (t->tx_buf) {
362 		ret = qspi_write_msg(qspi, t);
363 		if (ret) {
364 			dev_dbg(qspi->dev, "Error while writing\n");
365 			return ret;
366 		}
367 	}
368 
369 	if (t->rx_buf) {
370 		ret = qspi_read_msg(qspi, t);
371 		if (ret) {
372 			dev_dbg(qspi->dev, "Error while reading\n");
373 			return ret;
374 		}
375 	}
376 
377 	return 0;
378 }
379 
380 static void ti_qspi_enable_memory_map(struct spi_device *spi)
381 {
382 	struct ti_qspi  *qspi = spi_master_get_devdata(spi->master);
383 
384 	ti_qspi_write(qspi, MM_SWITCH, QSPI_SPI_SWITCH_REG);
385 	if (qspi->ctrl_base) {
386 		regmap_update_bits(qspi->ctrl_base, qspi->ctrl_reg,
387 				   MEM_CS_EN(spi->chip_select),
388 				   MEM_CS_MASK);
389 	}
390 	qspi->mmap_enabled = true;
391 }
392 
393 static void ti_qspi_disable_memory_map(struct spi_device *spi)
394 {
395 	struct ti_qspi  *qspi = spi_master_get_devdata(spi->master);
396 
397 	ti_qspi_write(qspi, 0, QSPI_SPI_SWITCH_REG);
398 	if (qspi->ctrl_base)
399 		regmap_update_bits(qspi->ctrl_base, qspi->ctrl_reg,
400 				   0, MEM_CS_MASK);
401 	qspi->mmap_enabled = false;
402 }
403 
404 static void ti_qspi_setup_mmap_read(struct spi_device *spi,
405 				    struct spi_flash_read_message *msg)
406 {
407 	struct ti_qspi  *qspi = spi_master_get_devdata(spi->master);
408 	u32 memval = msg->read_opcode;
409 
410 	switch (msg->data_nbits) {
411 	case SPI_NBITS_QUAD:
412 		memval |= QSPI_SETUP_RD_QUAD;
413 		break;
414 	case SPI_NBITS_DUAL:
415 		memval |= QSPI_SETUP_RD_DUAL;
416 		break;
417 	default:
418 		memval |= QSPI_SETUP_RD_NORMAL;
419 		break;
420 	}
421 	memval |= ((msg->addr_width - 1) << QSPI_SETUP_ADDR_SHIFT |
422 		   msg->dummy_bytes << QSPI_SETUP_DUMMY_SHIFT);
423 	ti_qspi_write(qspi, memval,
424 		      QSPI_SPI_SETUP_REG(spi->chip_select));
425 }
426 
427 static int ti_qspi_spi_flash_read(struct  spi_device *spi,
428 				  struct spi_flash_read_message *msg)
429 {
430 	struct ti_qspi *qspi = spi_master_get_devdata(spi->master);
431 	int ret = 0;
432 
433 	mutex_lock(&qspi->list_lock);
434 
435 	if (!qspi->mmap_enabled)
436 		ti_qspi_enable_memory_map(spi);
437 	ti_qspi_setup_mmap_read(spi, msg);
438 	memcpy_fromio(msg->buf, qspi->mmap_base + msg->from, msg->len);
439 	msg->retlen = msg->len;
440 
441 	mutex_unlock(&qspi->list_lock);
442 
443 	return ret;
444 }
445 
446 static int ti_qspi_start_transfer_one(struct spi_master *master,
447 		struct spi_message *m)
448 {
449 	struct ti_qspi *qspi = spi_master_get_devdata(master);
450 	struct spi_device *spi = m->spi;
451 	struct spi_transfer *t;
452 	int status = 0, ret;
453 	int frame_length;
454 
455 	/* setup device control reg */
456 	qspi->dc = 0;
457 
458 	if (spi->mode & SPI_CPHA)
459 		qspi->dc |= QSPI_CKPHA(spi->chip_select);
460 	if (spi->mode & SPI_CPOL)
461 		qspi->dc |= QSPI_CKPOL(spi->chip_select);
462 	if (spi->mode & SPI_CS_HIGH)
463 		qspi->dc |= QSPI_CSPOL(spi->chip_select);
464 
465 	frame_length = (m->frame_length << 3) / spi->bits_per_word;
466 
467 	frame_length = clamp(frame_length, 0, QSPI_FRAME);
468 
469 	/* setup command reg */
470 	qspi->cmd = 0;
471 	qspi->cmd |= QSPI_EN_CS(spi->chip_select);
472 	qspi->cmd |= QSPI_FLEN(frame_length);
473 
474 	ti_qspi_write(qspi, qspi->dc, QSPI_SPI_DC_REG);
475 
476 	mutex_lock(&qspi->list_lock);
477 
478 	if (qspi->mmap_enabled)
479 		ti_qspi_disable_memory_map(spi);
480 
481 	list_for_each_entry(t, &m->transfers, transfer_list) {
482 		qspi->cmd |= QSPI_WLEN(t->bits_per_word);
483 
484 		ret = qspi_transfer_msg(qspi, t);
485 		if (ret) {
486 			dev_dbg(qspi->dev, "transfer message failed\n");
487 			mutex_unlock(&qspi->list_lock);
488 			return -EINVAL;
489 		}
490 
491 		m->actual_length += t->len;
492 	}
493 
494 	mutex_unlock(&qspi->list_lock);
495 
496 	ti_qspi_write(qspi, qspi->cmd | QSPI_INVAL, QSPI_SPI_CMD_REG);
497 	m->status = status;
498 	spi_finalize_current_message(master);
499 
500 	return status;
501 }
502 
503 static int ti_qspi_runtime_resume(struct device *dev)
504 {
505 	struct ti_qspi      *qspi;
506 
507 	qspi = dev_get_drvdata(dev);
508 	ti_qspi_restore_ctx(qspi);
509 
510 	return 0;
511 }
512 
513 static const struct of_device_id ti_qspi_match[] = {
514 	{.compatible = "ti,dra7xxx-qspi" },
515 	{.compatible = "ti,am4372-qspi" },
516 	{},
517 };
518 MODULE_DEVICE_TABLE(of, ti_qspi_match);
519 
520 static int ti_qspi_probe(struct platform_device *pdev)
521 {
522 	struct  ti_qspi *qspi;
523 	struct spi_master *master;
524 	struct resource         *r, *res_mmap;
525 	struct device_node *np = pdev->dev.of_node;
526 	u32 max_freq;
527 	int ret = 0, num_cs, irq;
528 
529 	master = spi_alloc_master(&pdev->dev, sizeof(*qspi));
530 	if (!master)
531 		return -ENOMEM;
532 
533 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_RX_DUAL | SPI_RX_QUAD;
534 
535 	master->flags = SPI_MASTER_HALF_DUPLEX;
536 	master->setup = ti_qspi_setup;
537 	master->auto_runtime_pm = true;
538 	master->transfer_one_message = ti_qspi_start_transfer_one;
539 	master->dev.of_node = pdev->dev.of_node;
540 	master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) |
541 				     SPI_BPW_MASK(8);
542 
543 	if (!of_property_read_u32(np, "num-cs", &num_cs))
544 		master->num_chipselect = num_cs;
545 
546 	qspi = spi_master_get_devdata(master);
547 	qspi->master = master;
548 	qspi->dev = &pdev->dev;
549 	platform_set_drvdata(pdev, qspi);
550 
551 	r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi_base");
552 	if (r == NULL) {
553 		r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
554 		if (r == NULL) {
555 			dev_err(&pdev->dev, "missing platform data\n");
556 			return -ENODEV;
557 		}
558 	}
559 
560 	res_mmap = platform_get_resource_byname(pdev,
561 			IORESOURCE_MEM, "qspi_mmap");
562 	if (res_mmap == NULL) {
563 		res_mmap = platform_get_resource(pdev, IORESOURCE_MEM, 1);
564 		if (res_mmap == NULL) {
565 			dev_err(&pdev->dev,
566 				"memory mapped resource not required\n");
567 		}
568 	}
569 
570 	irq = platform_get_irq(pdev, 0);
571 	if (irq < 0) {
572 		dev_err(&pdev->dev, "no irq resource?\n");
573 		return irq;
574 	}
575 
576 	mutex_init(&qspi->list_lock);
577 
578 	qspi->base = devm_ioremap_resource(&pdev->dev, r);
579 	if (IS_ERR(qspi->base)) {
580 		ret = PTR_ERR(qspi->base);
581 		goto free_master;
582 	}
583 
584 	if (res_mmap) {
585 		qspi->mmap_base = devm_ioremap_resource(&pdev->dev,
586 							res_mmap);
587 		master->spi_flash_read = ti_qspi_spi_flash_read;
588 		if (IS_ERR(qspi->mmap_base)) {
589 			dev_err(&pdev->dev,
590 				"falling back to PIO mode\n");
591 			master->spi_flash_read = NULL;
592 		}
593 	}
594 	qspi->mmap_enabled = false;
595 
596 	if (of_property_read_bool(np, "syscon-chipselects")) {
597 		qspi->ctrl_base =
598 		syscon_regmap_lookup_by_phandle(np,
599 						"syscon-chipselects");
600 		if (IS_ERR(qspi->ctrl_base))
601 			return PTR_ERR(qspi->ctrl_base);
602 		ret = of_property_read_u32_index(np,
603 						 "syscon-chipselects",
604 						 1, &qspi->ctrl_reg);
605 		if (ret) {
606 			dev_err(&pdev->dev,
607 				"couldn't get ctrl_mod reg index\n");
608 			return ret;
609 		}
610 	}
611 
612 	qspi->fclk = devm_clk_get(&pdev->dev, "fck");
613 	if (IS_ERR(qspi->fclk)) {
614 		ret = PTR_ERR(qspi->fclk);
615 		dev_err(&pdev->dev, "could not get clk: %d\n", ret);
616 	}
617 
618 	pm_runtime_use_autosuspend(&pdev->dev);
619 	pm_runtime_set_autosuspend_delay(&pdev->dev, QSPI_AUTOSUSPEND_TIMEOUT);
620 	pm_runtime_enable(&pdev->dev);
621 
622 	if (!of_property_read_u32(np, "spi-max-frequency", &max_freq))
623 		qspi->spi_max_frequency = max_freq;
624 
625 	ret = devm_spi_register_master(&pdev->dev, master);
626 	if (ret)
627 		goto free_master;
628 
629 	return 0;
630 
631 free_master:
632 	spi_master_put(master);
633 	return ret;
634 }
635 
636 static int ti_qspi_remove(struct platform_device *pdev)
637 {
638 	pm_runtime_put_sync(&pdev->dev);
639 	pm_runtime_disable(&pdev->dev);
640 
641 	return 0;
642 }
643 
644 static const struct dev_pm_ops ti_qspi_pm_ops = {
645 	.runtime_resume = ti_qspi_runtime_resume,
646 };
647 
648 static struct platform_driver ti_qspi_driver = {
649 	.probe	= ti_qspi_probe,
650 	.remove = ti_qspi_remove,
651 	.driver = {
652 		.name	= "ti-qspi",
653 		.pm =   &ti_qspi_pm_ops,
654 		.of_match_table = ti_qspi_match,
655 	}
656 };
657 
658 module_platform_driver(ti_qspi_driver);
659 
660 MODULE_AUTHOR("Sourav Poddar <sourav.poddar@ti.com>");
661 MODULE_LICENSE("GPL v2");
662 MODULE_DESCRIPTION("TI QSPI controller driver");
663 MODULE_ALIAS("platform:ti-qspi");
664