xref: /linux/drivers/spi/spi-qcom-qspi.c (revision 122333d6bd229af279cdb35d1b874b71b3b9ccfb)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2017-2018, The Linux foundation. All rights reserved.
3 
4 #include <linux/clk.h>
5 #include <linux/interconnect.h>
6 #include <linux/interrupt.h>
7 #include <linux/io.h>
8 #include <linux/module.h>
9 #include <linux/of.h>
10 #include <linux/of_platform.h>
11 #include <linux/pinctrl/consumer.h>
12 #include <linux/pm_runtime.h>
13 #include <linux/pm_opp.h>
14 #include <linux/spi/spi.h>
15 #include <linux/spi/spi-mem.h>
16 
17 
18 #define QSPI_NUM_CS		2
19 #define QSPI_BYTES_PER_WORD	4
20 
21 #define MSTR_CONFIG		0x0000
22 #define FULL_CYCLE_MODE		BIT(3)
23 #define FB_CLK_EN		BIT(4)
24 #define PIN_HOLDN		BIT(6)
25 #define PIN_WPN			BIT(7)
26 #define DMA_ENABLE		BIT(8)
27 #define BIG_ENDIAN_MODE		BIT(9)
28 #define SPI_MODE_MSK		0xc00
29 #define SPI_MODE_SHFT		10
30 #define CHIP_SELECT_NUM		BIT(12)
31 #define SBL_EN			BIT(13)
32 #define LPA_BASE_MSK		0x3c000
33 #define LPA_BASE_SHFT		14
34 #define TX_DATA_DELAY_MSK	0xc0000
35 #define TX_DATA_DELAY_SHFT	18
36 #define TX_CLK_DELAY_MSK	0x300000
37 #define TX_CLK_DELAY_SHFT	20
38 #define TX_CS_N_DELAY_MSK	0xc00000
39 #define TX_CS_N_DELAY_SHFT	22
40 #define TX_DATA_OE_DELAY_MSK	0x3000000
41 #define TX_DATA_OE_DELAY_SHFT	24
42 
43 #define AHB_MASTER_CFG				0x0004
44 #define HMEM_TYPE_START_MID_TRANS_MSK		0x7
45 #define HMEM_TYPE_START_MID_TRANS_SHFT		0
46 #define HMEM_TYPE_LAST_TRANS_MSK		0x38
47 #define HMEM_TYPE_LAST_TRANS_SHFT		3
48 #define USE_HMEMTYPE_LAST_ON_DESC_OR_CHAIN_MSK	0xc0
49 #define USE_HMEMTYPE_LAST_ON_DESC_OR_CHAIN_SHFT	6
50 #define HMEMTYPE_READ_TRANS_MSK			0x700
51 #define HMEMTYPE_READ_TRANS_SHFT		8
52 #define HSHARED					BIT(11)
53 #define HINNERSHARED				BIT(12)
54 
55 #define MSTR_INT_EN		0x000C
56 #define MSTR_INT_STATUS		0x0010
57 #define RESP_FIFO_UNDERRUN	BIT(0)
58 #define RESP_FIFO_NOT_EMPTY	BIT(1)
59 #define RESP_FIFO_RDY		BIT(2)
60 #define HRESP_FROM_NOC_ERR	BIT(3)
61 #define WR_FIFO_EMPTY		BIT(9)
62 #define WR_FIFO_FULL		BIT(10)
63 #define WR_FIFO_OVERRUN		BIT(11)
64 #define TRANSACTION_DONE	BIT(16)
65 #define QSPI_ERR_IRQS		(RESP_FIFO_UNDERRUN | HRESP_FROM_NOC_ERR | \
66 				 WR_FIFO_OVERRUN)
67 #define QSPI_ALL_IRQS		(QSPI_ERR_IRQS | RESP_FIFO_RDY | \
68 				 WR_FIFO_EMPTY | WR_FIFO_FULL | \
69 				 TRANSACTION_DONE)
70 
71 #define PIO_XFER_CTRL		0x0014
72 #define REQUEST_COUNT_MSK	0xffff
73 
74 #define PIO_XFER_CFG		0x0018
75 #define TRANSFER_DIRECTION	BIT(0)
76 #define MULTI_IO_MODE_MSK	0xe
77 #define MULTI_IO_MODE_SHFT	1
78 #define TRANSFER_FRAGMENT	BIT(8)
79 #define SDR_1BIT		1
80 #define SDR_2BIT		2
81 #define SDR_4BIT		3
82 #define DDR_1BIT		5
83 #define DDR_2BIT		6
84 #define DDR_4BIT		7
85 #define DMA_DESC_SINGLE_SPI	1
86 #define DMA_DESC_DUAL_SPI	2
87 #define DMA_DESC_QUAD_SPI	3
88 
89 #define PIO_XFER_STATUS		0x001c
90 #define WR_FIFO_BYTES_MSK	0xffff0000
91 #define WR_FIFO_BYTES_SHFT	16
92 
93 #define PIO_DATAOUT_1B		0x0020
94 #define PIO_DATAOUT_4B		0x0024
95 
96 #define RD_FIFO_CFG		0x0028
97 #define CONTINUOUS_MODE		BIT(0)
98 
99 #define RD_FIFO_STATUS	0x002c
100 #define FIFO_EMPTY	BIT(11)
101 #define WR_CNTS_MSK	0x7f0
102 #define WR_CNTS_SHFT	4
103 #define RDY_64BYTE	BIT(3)
104 #define RDY_32BYTE	BIT(2)
105 #define RDY_16BYTE	BIT(1)
106 #define FIFO_RDY	BIT(0)
107 
108 #define RD_FIFO_RESET		0x0030
109 #define RESET_FIFO		BIT(0)
110 
111 #define CUR_MEM_ADDR		0x0048
112 #define HW_VERSION		0x004c
113 #define RD_FIFO			0x0050
114 #define SAMPLING_CLK_CFG	0x0090
115 #define SAMPLING_CLK_STATUS	0x0094
116 
117 
118 enum qspi_dir {
119 	QSPI_READ,
120 	QSPI_WRITE,
121 };
122 
123 struct qspi_xfer {
124 	union {
125 		const void *tx_buf;
126 		void *rx_buf;
127 	};
128 	unsigned int rem_bytes;
129 	unsigned int buswidth;
130 	enum qspi_dir dir;
131 	bool is_last;
132 };
133 
134 enum qspi_clocks {
135 	QSPI_CLK_CORE,
136 	QSPI_CLK_IFACE,
137 	QSPI_NUM_CLKS
138 };
139 
140 struct qcom_qspi {
141 	void __iomem *base;
142 	struct device *dev;
143 	struct clk_bulk_data *clks;
144 	struct qspi_xfer xfer;
145 	struct icc_path *icc_path_cpu_to_qspi;
146 	unsigned long last_speed;
147 	/* Lock to protect data accessed by IRQs */
148 	spinlock_t lock;
149 };
150 
151 static u32 qspi_buswidth_to_iomode(struct qcom_qspi *ctrl,
152 				   unsigned int buswidth)
153 {
154 	switch (buswidth) {
155 	case 1:
156 		return SDR_1BIT << MULTI_IO_MODE_SHFT;
157 	case 2:
158 		return SDR_2BIT << MULTI_IO_MODE_SHFT;
159 	case 4:
160 		return SDR_4BIT << MULTI_IO_MODE_SHFT;
161 	default:
162 		dev_warn_once(ctrl->dev,
163 				"Unexpected bus width: %u\n", buswidth);
164 		return SDR_1BIT << MULTI_IO_MODE_SHFT;
165 	}
166 }
167 
168 static void qcom_qspi_pio_xfer_cfg(struct qcom_qspi *ctrl)
169 {
170 	u32 pio_xfer_cfg;
171 	const struct qspi_xfer *xfer;
172 
173 	xfer = &ctrl->xfer;
174 	pio_xfer_cfg = readl(ctrl->base + PIO_XFER_CFG);
175 	pio_xfer_cfg &= ~TRANSFER_DIRECTION;
176 	pio_xfer_cfg |= xfer->dir;
177 	if (xfer->is_last)
178 		pio_xfer_cfg &= ~TRANSFER_FRAGMENT;
179 	else
180 		pio_xfer_cfg |= TRANSFER_FRAGMENT;
181 	pio_xfer_cfg &= ~MULTI_IO_MODE_MSK;
182 	pio_xfer_cfg |= qspi_buswidth_to_iomode(ctrl, xfer->buswidth);
183 
184 	writel(pio_xfer_cfg, ctrl->base + PIO_XFER_CFG);
185 }
186 
187 static void qcom_qspi_pio_xfer_ctrl(struct qcom_qspi *ctrl)
188 {
189 	u32 pio_xfer_ctrl;
190 
191 	pio_xfer_ctrl = readl(ctrl->base + PIO_XFER_CTRL);
192 	pio_xfer_ctrl &= ~REQUEST_COUNT_MSK;
193 	pio_xfer_ctrl |= ctrl->xfer.rem_bytes;
194 	writel(pio_xfer_ctrl, ctrl->base + PIO_XFER_CTRL);
195 }
196 
197 static void qcom_qspi_pio_xfer(struct qcom_qspi *ctrl)
198 {
199 	u32 ints;
200 
201 	qcom_qspi_pio_xfer_cfg(ctrl);
202 
203 	/* Ack any previous interrupts that might be hanging around */
204 	writel(QSPI_ALL_IRQS, ctrl->base + MSTR_INT_STATUS);
205 
206 	/* Setup new interrupts */
207 	if (ctrl->xfer.dir == QSPI_WRITE)
208 		ints = QSPI_ERR_IRQS | WR_FIFO_EMPTY;
209 	else
210 		ints = QSPI_ERR_IRQS | RESP_FIFO_RDY;
211 	writel(ints, ctrl->base + MSTR_INT_EN);
212 
213 	/* Kick off the transfer */
214 	qcom_qspi_pio_xfer_ctrl(ctrl);
215 }
216 
217 static void qcom_qspi_handle_err(struct spi_master *master,
218 				 struct spi_message *msg)
219 {
220 	struct qcom_qspi *ctrl = spi_master_get_devdata(master);
221 	unsigned long flags;
222 
223 	spin_lock_irqsave(&ctrl->lock, flags);
224 	writel(0, ctrl->base + MSTR_INT_EN);
225 	ctrl->xfer.rem_bytes = 0;
226 	spin_unlock_irqrestore(&ctrl->lock, flags);
227 }
228 
229 static int qcom_qspi_set_speed(struct qcom_qspi *ctrl, unsigned long speed_hz)
230 {
231 	int ret;
232 	unsigned int avg_bw_cpu;
233 
234 	if (speed_hz == ctrl->last_speed)
235 		return 0;
236 
237 	/* In regular operation (SBL_EN=1) core must be 4x transfer clock */
238 	ret = dev_pm_opp_set_rate(ctrl->dev, speed_hz * 4);
239 	if (ret) {
240 		dev_err(ctrl->dev, "Failed to set core clk %d\n", ret);
241 		return ret;
242 	}
243 
244 	/*
245 	 * Set BW quota for CPU as driver supports FIFO mode only.
246 	 * We don't have explicit peak requirement so keep it equal to avg_bw.
247 	 */
248 	avg_bw_cpu = Bps_to_icc(speed_hz);
249 	ret = icc_set_bw(ctrl->icc_path_cpu_to_qspi, avg_bw_cpu, avg_bw_cpu);
250 	if (ret) {
251 		dev_err(ctrl->dev, "%s: ICC BW voting failed for cpu: %d\n",
252 			__func__, ret);
253 		return ret;
254 	}
255 
256 	ctrl->last_speed = speed_hz;
257 
258 	return 0;
259 }
260 
261 static int qcom_qspi_transfer_one(struct spi_master *master,
262 				  struct spi_device *slv,
263 				  struct spi_transfer *xfer)
264 {
265 	struct qcom_qspi *ctrl = spi_master_get_devdata(master);
266 	int ret;
267 	unsigned long speed_hz;
268 	unsigned long flags;
269 
270 	speed_hz = slv->max_speed_hz;
271 	if (xfer->speed_hz)
272 		speed_hz = xfer->speed_hz;
273 
274 	ret = qcom_qspi_set_speed(ctrl, speed_hz);
275 	if (ret)
276 		return ret;
277 
278 	spin_lock_irqsave(&ctrl->lock, flags);
279 
280 	/* We are half duplex, so either rx or tx will be set */
281 	if (xfer->rx_buf) {
282 		ctrl->xfer.dir = QSPI_READ;
283 		ctrl->xfer.buswidth = xfer->rx_nbits;
284 		ctrl->xfer.rx_buf = xfer->rx_buf;
285 	} else {
286 		ctrl->xfer.dir = QSPI_WRITE;
287 		ctrl->xfer.buswidth = xfer->tx_nbits;
288 		ctrl->xfer.tx_buf = xfer->tx_buf;
289 	}
290 	ctrl->xfer.is_last = list_is_last(&xfer->transfer_list,
291 					  &master->cur_msg->transfers);
292 	ctrl->xfer.rem_bytes = xfer->len;
293 	qcom_qspi_pio_xfer(ctrl);
294 
295 	spin_unlock_irqrestore(&ctrl->lock, flags);
296 
297 	/* We'll call spi_finalize_current_transfer() when done */
298 	return 1;
299 }
300 
301 static int qcom_qspi_prepare_message(struct spi_master *master,
302 				     struct spi_message *message)
303 {
304 	u32 mstr_cfg;
305 	struct qcom_qspi *ctrl;
306 	int tx_data_oe_delay = 1;
307 	int tx_data_delay = 1;
308 	unsigned long flags;
309 
310 	ctrl = spi_master_get_devdata(master);
311 	spin_lock_irqsave(&ctrl->lock, flags);
312 
313 	mstr_cfg = readl(ctrl->base + MSTR_CONFIG);
314 	mstr_cfg &= ~CHIP_SELECT_NUM;
315 	if (spi_get_chipselect(message->spi, 0))
316 		mstr_cfg |= CHIP_SELECT_NUM;
317 
318 	mstr_cfg |= FB_CLK_EN | PIN_WPN | PIN_HOLDN | SBL_EN | FULL_CYCLE_MODE;
319 	mstr_cfg &= ~(SPI_MODE_MSK | TX_DATA_OE_DELAY_MSK | TX_DATA_DELAY_MSK);
320 	mstr_cfg |= message->spi->mode << SPI_MODE_SHFT;
321 	mstr_cfg |= tx_data_oe_delay << TX_DATA_OE_DELAY_SHFT;
322 	mstr_cfg |= tx_data_delay << TX_DATA_DELAY_SHFT;
323 	mstr_cfg &= ~DMA_ENABLE;
324 
325 	writel(mstr_cfg, ctrl->base + MSTR_CONFIG);
326 	spin_unlock_irqrestore(&ctrl->lock, flags);
327 
328 	return 0;
329 }
330 
331 static irqreturn_t pio_read(struct qcom_qspi *ctrl)
332 {
333 	u32 rd_fifo_status;
334 	u32 rd_fifo;
335 	unsigned int wr_cnts;
336 	unsigned int bytes_to_read;
337 	unsigned int words_to_read;
338 	u32 *word_buf;
339 	u8 *byte_buf;
340 	int i;
341 
342 	rd_fifo_status = readl(ctrl->base + RD_FIFO_STATUS);
343 
344 	if (!(rd_fifo_status & FIFO_RDY)) {
345 		dev_dbg(ctrl->dev, "Spurious IRQ %#x\n", rd_fifo_status);
346 		return IRQ_NONE;
347 	}
348 
349 	wr_cnts = (rd_fifo_status & WR_CNTS_MSK) >> WR_CNTS_SHFT;
350 	wr_cnts = min(wr_cnts, ctrl->xfer.rem_bytes);
351 
352 	words_to_read = wr_cnts / QSPI_BYTES_PER_WORD;
353 	bytes_to_read = wr_cnts % QSPI_BYTES_PER_WORD;
354 
355 	if (words_to_read) {
356 		word_buf = ctrl->xfer.rx_buf;
357 		ctrl->xfer.rem_bytes -= words_to_read * QSPI_BYTES_PER_WORD;
358 		ioread32_rep(ctrl->base + RD_FIFO, word_buf, words_to_read);
359 		ctrl->xfer.rx_buf = word_buf + words_to_read;
360 	}
361 
362 	if (bytes_to_read) {
363 		byte_buf = ctrl->xfer.rx_buf;
364 		rd_fifo = readl(ctrl->base + RD_FIFO);
365 		ctrl->xfer.rem_bytes -= bytes_to_read;
366 		for (i = 0; i < bytes_to_read; i++)
367 			*byte_buf++ = rd_fifo >> (i * BITS_PER_BYTE);
368 		ctrl->xfer.rx_buf = byte_buf;
369 	}
370 
371 	return IRQ_HANDLED;
372 }
373 
374 static irqreturn_t pio_write(struct qcom_qspi *ctrl)
375 {
376 	const void *xfer_buf = ctrl->xfer.tx_buf;
377 	const int *word_buf;
378 	const char *byte_buf;
379 	unsigned int wr_fifo_bytes;
380 	unsigned int wr_fifo_words;
381 	unsigned int wr_size;
382 	unsigned int rem_words;
383 
384 	wr_fifo_bytes = readl(ctrl->base + PIO_XFER_STATUS);
385 	wr_fifo_bytes >>= WR_FIFO_BYTES_SHFT;
386 
387 	if (ctrl->xfer.rem_bytes < QSPI_BYTES_PER_WORD) {
388 		/* Process the last 1-3 bytes */
389 		wr_size = min(wr_fifo_bytes, ctrl->xfer.rem_bytes);
390 		ctrl->xfer.rem_bytes -= wr_size;
391 
392 		byte_buf = xfer_buf;
393 		while (wr_size--)
394 			writel(*byte_buf++,
395 			       ctrl->base + PIO_DATAOUT_1B);
396 		ctrl->xfer.tx_buf = byte_buf;
397 	} else {
398 		/*
399 		 * Process all the whole words; to keep things simple we'll
400 		 * just wait for the next interrupt to handle the last 1-3
401 		 * bytes if we don't have an even number of words.
402 		 */
403 		rem_words = ctrl->xfer.rem_bytes / QSPI_BYTES_PER_WORD;
404 		wr_fifo_words = wr_fifo_bytes / QSPI_BYTES_PER_WORD;
405 
406 		wr_size = min(rem_words, wr_fifo_words);
407 		ctrl->xfer.rem_bytes -= wr_size * QSPI_BYTES_PER_WORD;
408 
409 		word_buf = xfer_buf;
410 		iowrite32_rep(ctrl->base + PIO_DATAOUT_4B, word_buf, wr_size);
411 		ctrl->xfer.tx_buf = word_buf + wr_size;
412 
413 	}
414 
415 	return IRQ_HANDLED;
416 }
417 
418 static irqreturn_t qcom_qspi_irq(int irq, void *dev_id)
419 {
420 	u32 int_status;
421 	struct qcom_qspi *ctrl = dev_id;
422 	irqreturn_t ret = IRQ_NONE;
423 
424 	spin_lock(&ctrl->lock);
425 
426 	int_status = readl(ctrl->base + MSTR_INT_STATUS);
427 	writel(int_status, ctrl->base + MSTR_INT_STATUS);
428 
429 	if (ctrl->xfer.dir == QSPI_WRITE) {
430 		if (int_status & WR_FIFO_EMPTY)
431 			ret = pio_write(ctrl);
432 	} else {
433 		if (int_status & RESP_FIFO_RDY)
434 			ret = pio_read(ctrl);
435 	}
436 
437 	if (int_status & QSPI_ERR_IRQS) {
438 		if (int_status & RESP_FIFO_UNDERRUN)
439 			dev_err(ctrl->dev, "IRQ error: FIFO underrun\n");
440 		if (int_status & WR_FIFO_OVERRUN)
441 			dev_err(ctrl->dev, "IRQ error: FIFO overrun\n");
442 		if (int_status & HRESP_FROM_NOC_ERR)
443 			dev_err(ctrl->dev, "IRQ error: NOC response error\n");
444 		ret = IRQ_HANDLED;
445 	}
446 
447 	if (!ctrl->xfer.rem_bytes) {
448 		writel(0, ctrl->base + MSTR_INT_EN);
449 		spi_finalize_current_transfer(dev_get_drvdata(ctrl->dev));
450 	}
451 
452 	spin_unlock(&ctrl->lock);
453 	return ret;
454 }
455 
456 static int qcom_qspi_probe(struct platform_device *pdev)
457 {
458 	int ret;
459 	struct device *dev;
460 	struct spi_master *master;
461 	struct qcom_qspi *ctrl;
462 
463 	dev = &pdev->dev;
464 
465 	master = devm_spi_alloc_master(dev, sizeof(*ctrl));
466 	if (!master)
467 		return -ENOMEM;
468 
469 	platform_set_drvdata(pdev, master);
470 
471 	ctrl = spi_master_get_devdata(master);
472 
473 	spin_lock_init(&ctrl->lock);
474 	ctrl->dev = dev;
475 	ctrl->base = devm_platform_ioremap_resource(pdev, 0);
476 	if (IS_ERR(ctrl->base))
477 		return PTR_ERR(ctrl->base);
478 
479 	ctrl->clks = devm_kcalloc(dev, QSPI_NUM_CLKS,
480 				  sizeof(*ctrl->clks), GFP_KERNEL);
481 	if (!ctrl->clks)
482 		return -ENOMEM;
483 
484 	ctrl->clks[QSPI_CLK_CORE].id = "core";
485 	ctrl->clks[QSPI_CLK_IFACE].id = "iface";
486 	ret = devm_clk_bulk_get(dev, QSPI_NUM_CLKS, ctrl->clks);
487 	if (ret)
488 		return ret;
489 
490 	ctrl->icc_path_cpu_to_qspi = devm_of_icc_get(dev, "qspi-config");
491 	if (IS_ERR(ctrl->icc_path_cpu_to_qspi))
492 		return dev_err_probe(dev, PTR_ERR(ctrl->icc_path_cpu_to_qspi),
493 				     "Failed to get cpu path\n");
494 
495 	/* Set BW vote for register access */
496 	ret = icc_set_bw(ctrl->icc_path_cpu_to_qspi, Bps_to_icc(1000),
497 				Bps_to_icc(1000));
498 	if (ret) {
499 		dev_err(ctrl->dev, "%s: ICC BW voting failed for cpu: %d\n",
500 				__func__, ret);
501 		return ret;
502 	}
503 
504 	ret = icc_disable(ctrl->icc_path_cpu_to_qspi);
505 	if (ret) {
506 		dev_err(ctrl->dev, "%s: ICC disable failed for cpu: %d\n",
507 				__func__, ret);
508 		return ret;
509 	}
510 
511 	ret = platform_get_irq(pdev, 0);
512 	if (ret < 0)
513 		return ret;
514 	ret = devm_request_irq(dev, ret, qcom_qspi_irq, 0, dev_name(dev), ctrl);
515 	if (ret) {
516 		dev_err(dev, "Failed to request irq %d\n", ret);
517 		return ret;
518 	}
519 
520 	master->max_speed_hz = 300000000;
521 	master->num_chipselect = QSPI_NUM_CS;
522 	master->bus_num = -1;
523 	master->dev.of_node = pdev->dev.of_node;
524 	master->mode_bits = SPI_MODE_0 |
525 			    SPI_TX_DUAL | SPI_RX_DUAL |
526 			    SPI_TX_QUAD | SPI_RX_QUAD;
527 	master->flags = SPI_MASTER_HALF_DUPLEX;
528 	master->prepare_message = qcom_qspi_prepare_message;
529 	master->transfer_one = qcom_qspi_transfer_one;
530 	master->handle_err = qcom_qspi_handle_err;
531 	master->auto_runtime_pm = true;
532 
533 	ret = devm_pm_opp_set_clkname(&pdev->dev, "core");
534 	if (ret)
535 		return ret;
536 	/* OPP table is optional */
537 	ret = devm_pm_opp_of_add_table(&pdev->dev);
538 	if (ret && ret != -ENODEV) {
539 		dev_err(&pdev->dev, "invalid OPP table in device tree\n");
540 		return ret;
541 	}
542 
543 	pm_runtime_use_autosuspend(dev);
544 	pm_runtime_set_autosuspend_delay(dev, 250);
545 	pm_runtime_enable(dev);
546 
547 	ret = spi_register_master(master);
548 	if (!ret)
549 		return 0;
550 
551 	pm_runtime_disable(dev);
552 
553 	return ret;
554 }
555 
556 static void qcom_qspi_remove(struct platform_device *pdev)
557 {
558 	struct spi_master *master = platform_get_drvdata(pdev);
559 
560 	/* Unregister _before_ disabling pm_runtime() so we stop transfers */
561 	spi_unregister_master(master);
562 
563 	pm_runtime_disable(&pdev->dev);
564 }
565 
566 static int __maybe_unused qcom_qspi_runtime_suspend(struct device *dev)
567 {
568 	struct spi_master *master = dev_get_drvdata(dev);
569 	struct qcom_qspi *ctrl = spi_master_get_devdata(master);
570 	int ret;
571 
572 	/* Drop the performance state vote */
573 	dev_pm_opp_set_rate(dev, 0);
574 	clk_bulk_disable_unprepare(QSPI_NUM_CLKS, ctrl->clks);
575 
576 	ret = icc_disable(ctrl->icc_path_cpu_to_qspi);
577 	if (ret) {
578 		dev_err_ratelimited(ctrl->dev, "%s: ICC disable failed for cpu: %d\n",
579 			__func__, ret);
580 		return ret;
581 	}
582 
583 	pinctrl_pm_select_sleep_state(dev);
584 
585 	return 0;
586 }
587 
588 static int __maybe_unused qcom_qspi_runtime_resume(struct device *dev)
589 {
590 	struct spi_master *master = dev_get_drvdata(dev);
591 	struct qcom_qspi *ctrl = spi_master_get_devdata(master);
592 	int ret;
593 
594 	pinctrl_pm_select_default_state(dev);
595 
596 	ret = icc_enable(ctrl->icc_path_cpu_to_qspi);
597 	if (ret) {
598 		dev_err_ratelimited(ctrl->dev, "%s: ICC enable failed for cpu: %d\n",
599 			__func__, ret);
600 		return ret;
601 	}
602 
603 	ret = clk_bulk_prepare_enable(QSPI_NUM_CLKS, ctrl->clks);
604 	if (ret)
605 		return ret;
606 
607 	return dev_pm_opp_set_rate(dev, ctrl->last_speed * 4);
608 }
609 
610 static int __maybe_unused qcom_qspi_suspend(struct device *dev)
611 {
612 	struct spi_master *master = dev_get_drvdata(dev);
613 	int ret;
614 
615 	ret = spi_master_suspend(master);
616 	if (ret)
617 		return ret;
618 
619 	ret = pm_runtime_force_suspend(dev);
620 	if (ret)
621 		spi_master_resume(master);
622 
623 	return ret;
624 }
625 
626 static int __maybe_unused qcom_qspi_resume(struct device *dev)
627 {
628 	struct spi_master *master = dev_get_drvdata(dev);
629 	int ret;
630 
631 	ret = pm_runtime_force_resume(dev);
632 	if (ret)
633 		return ret;
634 
635 	ret = spi_master_resume(master);
636 	if (ret)
637 		pm_runtime_force_suspend(dev);
638 
639 	return ret;
640 }
641 
642 static const struct dev_pm_ops qcom_qspi_dev_pm_ops = {
643 	SET_RUNTIME_PM_OPS(qcom_qspi_runtime_suspend,
644 			   qcom_qspi_runtime_resume, NULL)
645 	SET_SYSTEM_SLEEP_PM_OPS(qcom_qspi_suspend, qcom_qspi_resume)
646 };
647 
648 static const struct of_device_id qcom_qspi_dt_match[] = {
649 	{ .compatible = "qcom,qspi-v1", },
650 	{ }
651 };
652 MODULE_DEVICE_TABLE(of, qcom_qspi_dt_match);
653 
654 static struct platform_driver qcom_qspi_driver = {
655 	.driver = {
656 		.name		= "qcom_qspi",
657 		.pm		= &qcom_qspi_dev_pm_ops,
658 		.of_match_table = qcom_qspi_dt_match,
659 	},
660 	.probe = qcom_qspi_probe,
661 	.remove_new = qcom_qspi_remove,
662 };
663 module_platform_driver(qcom_qspi_driver);
664 
665 MODULE_DESCRIPTION("SPI driver for QSPI cores");
666 MODULE_LICENSE("GPL v2");
667