xref: /linux/drivers/spi/spi-rockchip.c (revision e0bf6c5ca2d3281f231c5f0c9bf145e9513644de)
1 /*
2  * Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd
3  * Author: Addy Ke <addy.ke@rock-chips.com>
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms and conditions of the GNU General Public License,
7  * version 2, as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  *
14  */
15 
16 #include <linux/init.h>
17 #include <linux/module.h>
18 #include <linux/clk.h>
19 #include <linux/err.h>
20 #include <linux/delay.h>
21 #include <linux/interrupt.h>
22 #include <linux/platform_device.h>
23 #include <linux/slab.h>
24 #include <linux/spi/spi.h>
25 #include <linux/scatterlist.h>
26 #include <linux/of.h>
27 #include <linux/pm_runtime.h>
28 #include <linux/io.h>
29 #include <linux/dmaengine.h>
30 
31 #define DRIVER_NAME "rockchip-spi"
32 
33 /* SPI register offsets */
34 #define ROCKCHIP_SPI_CTRLR0			0x0000
35 #define ROCKCHIP_SPI_CTRLR1			0x0004
36 #define ROCKCHIP_SPI_SSIENR			0x0008
37 #define ROCKCHIP_SPI_SER			0x000c
38 #define ROCKCHIP_SPI_BAUDR			0x0010
39 #define ROCKCHIP_SPI_TXFTLR			0x0014
40 #define ROCKCHIP_SPI_RXFTLR			0x0018
41 #define ROCKCHIP_SPI_TXFLR			0x001c
42 #define ROCKCHIP_SPI_RXFLR			0x0020
43 #define ROCKCHIP_SPI_SR				0x0024
44 #define ROCKCHIP_SPI_IPR			0x0028
45 #define ROCKCHIP_SPI_IMR			0x002c
46 #define ROCKCHIP_SPI_ISR			0x0030
47 #define ROCKCHIP_SPI_RISR			0x0034
48 #define ROCKCHIP_SPI_ICR			0x0038
49 #define ROCKCHIP_SPI_DMACR			0x003c
50 #define ROCKCHIP_SPI_DMATDLR		0x0040
51 #define ROCKCHIP_SPI_DMARDLR		0x0044
52 #define ROCKCHIP_SPI_TXDR			0x0400
53 #define ROCKCHIP_SPI_RXDR			0x0800
54 
55 /* Bit fields in CTRLR0 */
56 #define CR0_DFS_OFFSET				0
57 
58 #define CR0_CFS_OFFSET				2
59 
60 #define CR0_SCPH_OFFSET				6
61 
62 #define CR0_SCPOL_OFFSET			7
63 
64 #define CR0_CSM_OFFSET				8
65 #define CR0_CSM_KEEP				0x0
66 /* ss_n be high for half sclk_out cycles */
67 #define CR0_CSM_HALF				0X1
68 /* ss_n be high for one sclk_out cycle */
69 #define CR0_CSM_ONE					0x2
70 
71 /* ss_n to sclk_out delay */
72 #define CR0_SSD_OFFSET				10
73 /*
74  * The period between ss_n active and
75  * sclk_out active is half sclk_out cycles
76  */
77 #define CR0_SSD_HALF				0x0
78 /*
79  * The period between ss_n active and
80  * sclk_out active is one sclk_out cycle
81  */
82 #define CR0_SSD_ONE					0x1
83 
84 #define CR0_EM_OFFSET				11
85 #define CR0_EM_LITTLE				0x0
86 #define CR0_EM_BIG					0x1
87 
88 #define CR0_FBM_OFFSET				12
89 #define CR0_FBM_MSB					0x0
90 #define CR0_FBM_LSB					0x1
91 
92 #define CR0_BHT_OFFSET				13
93 #define CR0_BHT_16BIT				0x0
94 #define CR0_BHT_8BIT				0x1
95 
96 #define CR0_RSD_OFFSET				14
97 
98 #define CR0_FRF_OFFSET				16
99 #define CR0_FRF_SPI					0x0
100 #define CR0_FRF_SSP					0x1
101 #define CR0_FRF_MICROWIRE			0x2
102 
103 #define CR0_XFM_OFFSET				18
104 #define CR0_XFM_MASK				(0x03 << SPI_XFM_OFFSET)
105 #define CR0_XFM_TR					0x0
106 #define CR0_XFM_TO					0x1
107 #define CR0_XFM_RO					0x2
108 
109 #define CR0_OPM_OFFSET				20
110 #define CR0_OPM_MASTER				0x0
111 #define CR0_OPM_SLAVE				0x1
112 
113 #define CR0_MTM_OFFSET				0x21
114 
115 /* Bit fields in SER, 2bit */
116 #define SER_MASK					0x3
117 
118 /* Bit fields in SR, 5bit */
119 #define SR_MASK						0x1f
120 #define SR_BUSY						(1 << 0)
121 #define SR_TF_FULL					(1 << 1)
122 #define SR_TF_EMPTY					(1 << 2)
123 #define SR_RF_EMPTY					(1 << 3)
124 #define SR_RF_FULL					(1 << 4)
125 
126 /* Bit fields in ISR, IMR, ISR, RISR, 5bit */
127 #define INT_MASK					0x1f
128 #define INT_TF_EMPTY				(1 << 0)
129 #define INT_TF_OVERFLOW				(1 << 1)
130 #define INT_RF_UNDERFLOW			(1 << 2)
131 #define INT_RF_OVERFLOW				(1 << 3)
132 #define INT_RF_FULL					(1 << 4)
133 
134 /* Bit fields in ICR, 4bit */
135 #define ICR_MASK					0x0f
136 #define ICR_ALL						(1 << 0)
137 #define ICR_RF_UNDERFLOW			(1 << 1)
138 #define ICR_RF_OVERFLOW				(1 << 2)
139 #define ICR_TF_OVERFLOW				(1 << 3)
140 
141 /* Bit fields in DMACR */
142 #define RF_DMA_EN					(1 << 0)
143 #define TF_DMA_EN					(1 << 1)
144 
145 #define RXBUSY						(1 << 0)
146 #define TXBUSY						(1 << 1)
147 
148 /* sclk_out: spi master internal logic in rk3x can support 50Mhz */
149 #define MAX_SCLK_OUT		50000000
150 
151 enum rockchip_ssi_type {
152 	SSI_MOTO_SPI = 0,
153 	SSI_TI_SSP,
154 	SSI_NS_MICROWIRE,
155 };
156 
157 struct rockchip_spi_dma_data {
158 	struct dma_chan *ch;
159 	enum dma_transfer_direction direction;
160 	dma_addr_t addr;
161 };
162 
163 struct rockchip_spi {
164 	struct device *dev;
165 	struct spi_master *master;
166 
167 	struct clk *spiclk;
168 	struct clk *apb_pclk;
169 
170 	void __iomem *regs;
171 	/*depth of the FIFO buffer */
172 	u32 fifo_len;
173 	/* max bus freq supported */
174 	u32 max_freq;
175 	/* supported slave numbers */
176 	enum rockchip_ssi_type type;
177 
178 	u16 mode;
179 	u8 tmode;
180 	u8 bpw;
181 	u8 n_bytes;
182 	unsigned len;
183 	u32 speed;
184 
185 	const void *tx;
186 	const void *tx_end;
187 	void *rx;
188 	void *rx_end;
189 
190 	u32 state;
191 	/* protect state */
192 	spinlock_t lock;
193 
194 	struct completion xfer_completion;
195 
196 	u32 use_dma;
197 	struct sg_table tx_sg;
198 	struct sg_table rx_sg;
199 	struct rockchip_spi_dma_data dma_rx;
200 	struct rockchip_spi_dma_data dma_tx;
201 };
202 
203 static inline void spi_enable_chip(struct rockchip_spi *rs, int enable)
204 {
205 	writel_relaxed((enable ? 1 : 0), rs->regs + ROCKCHIP_SPI_SSIENR);
206 }
207 
208 static inline void spi_set_clk(struct rockchip_spi *rs, u16 div)
209 {
210 	writel_relaxed(div, rs->regs + ROCKCHIP_SPI_BAUDR);
211 }
212 
213 static inline void flush_fifo(struct rockchip_spi *rs)
214 {
215 	while (readl_relaxed(rs->regs + ROCKCHIP_SPI_RXFLR))
216 		readl_relaxed(rs->regs + ROCKCHIP_SPI_RXDR);
217 }
218 
219 static inline void wait_for_idle(struct rockchip_spi *rs)
220 {
221 	unsigned long timeout = jiffies + msecs_to_jiffies(5);
222 
223 	do {
224 		if (!(readl_relaxed(rs->regs + ROCKCHIP_SPI_SR) & SR_BUSY))
225 			return;
226 	} while (!time_after(jiffies, timeout));
227 
228 	dev_warn(rs->dev, "spi controller is in busy state!\n");
229 }
230 
231 static u32 get_fifo_len(struct rockchip_spi *rs)
232 {
233 	u32 fifo;
234 
235 	for (fifo = 2; fifo < 32; fifo++) {
236 		writel_relaxed(fifo, rs->regs + ROCKCHIP_SPI_TXFTLR);
237 		if (fifo != readl_relaxed(rs->regs + ROCKCHIP_SPI_TXFTLR))
238 			break;
239 	}
240 
241 	writel_relaxed(0, rs->regs + ROCKCHIP_SPI_TXFTLR);
242 
243 	return (fifo == 31) ? 0 : fifo;
244 }
245 
246 static inline u32 tx_max(struct rockchip_spi *rs)
247 {
248 	u32 tx_left, tx_room;
249 
250 	tx_left = (rs->tx_end - rs->tx) / rs->n_bytes;
251 	tx_room = rs->fifo_len - readl_relaxed(rs->regs + ROCKCHIP_SPI_TXFLR);
252 
253 	return min(tx_left, tx_room);
254 }
255 
256 static inline u32 rx_max(struct rockchip_spi *rs)
257 {
258 	u32 rx_left = (rs->rx_end - rs->rx) / rs->n_bytes;
259 	u32 rx_room = (u32)readl_relaxed(rs->regs + ROCKCHIP_SPI_RXFLR);
260 
261 	return min(rx_left, rx_room);
262 }
263 
264 static void rockchip_spi_set_cs(struct spi_device *spi, bool enable)
265 {
266 	u32 ser;
267 	struct rockchip_spi *rs = spi_master_get_devdata(spi->master);
268 
269 	ser = readl_relaxed(rs->regs + ROCKCHIP_SPI_SER) & SER_MASK;
270 
271 	/*
272 	 * drivers/spi/spi.c:
273 	 * static void spi_set_cs(struct spi_device *spi, bool enable)
274 	 * {
275 	 *		if (spi->mode & SPI_CS_HIGH)
276 	 *			enable = !enable;
277 	 *
278 	 *		if (spi->cs_gpio >= 0)
279 	 *			gpio_set_value(spi->cs_gpio, !enable);
280 	 *		else if (spi->master->set_cs)
281 	 *		spi->master->set_cs(spi, !enable);
282 	 * }
283 	 *
284 	 * Note: enable(rockchip_spi_set_cs) = !enable(spi_set_cs)
285 	 */
286 	if (!enable)
287 		ser |= 1 << spi->chip_select;
288 	else
289 		ser &= ~(1 << spi->chip_select);
290 
291 	writel_relaxed(ser, rs->regs + ROCKCHIP_SPI_SER);
292 }
293 
294 static int rockchip_spi_prepare_message(struct spi_master *master,
295 					struct spi_message *msg)
296 {
297 	struct rockchip_spi *rs = spi_master_get_devdata(master);
298 	struct spi_device *spi = msg->spi;
299 
300 	rs->mode = spi->mode;
301 
302 	return 0;
303 }
304 
305 static int rockchip_spi_unprepare_message(struct spi_master *master,
306 					  struct spi_message *msg)
307 {
308 	unsigned long flags;
309 	struct rockchip_spi *rs = spi_master_get_devdata(master);
310 
311 	spin_lock_irqsave(&rs->lock, flags);
312 
313 	/*
314 	 * For DMA mode, we need terminate DMA channel and flush
315 	 * fifo for the next transfer if DMA thansfer timeout.
316 	 * unprepare_message() was called by core if transfer complete
317 	 * or timeout. Maybe it is reasonable for error handling here.
318 	 */
319 	if (rs->use_dma) {
320 		if (rs->state & RXBUSY) {
321 			dmaengine_terminate_all(rs->dma_rx.ch);
322 			flush_fifo(rs);
323 		}
324 
325 		if (rs->state & TXBUSY)
326 			dmaengine_terminate_all(rs->dma_tx.ch);
327 	}
328 
329 	spin_unlock_irqrestore(&rs->lock, flags);
330 
331 	spi_enable_chip(rs, 0);
332 
333 	return 0;
334 }
335 
336 static void rockchip_spi_pio_writer(struct rockchip_spi *rs)
337 {
338 	u32 max = tx_max(rs);
339 	u32 txw = 0;
340 
341 	while (max--) {
342 		if (rs->n_bytes == 1)
343 			txw = *(u8 *)(rs->tx);
344 		else
345 			txw = *(u16 *)(rs->tx);
346 
347 		writel_relaxed(txw, rs->regs + ROCKCHIP_SPI_TXDR);
348 		rs->tx += rs->n_bytes;
349 	}
350 }
351 
352 static void rockchip_spi_pio_reader(struct rockchip_spi *rs)
353 {
354 	u32 max = rx_max(rs);
355 	u32 rxw;
356 
357 	while (max--) {
358 		rxw = readl_relaxed(rs->regs + ROCKCHIP_SPI_RXDR);
359 		if (rs->n_bytes == 1)
360 			*(u8 *)(rs->rx) = (u8)rxw;
361 		else
362 			*(u16 *)(rs->rx) = (u16)rxw;
363 		rs->rx += rs->n_bytes;
364 	}
365 }
366 
367 static int rockchip_spi_pio_transfer(struct rockchip_spi *rs)
368 {
369 	int remain = 0;
370 
371 	do {
372 		if (rs->tx) {
373 			remain = rs->tx_end - rs->tx;
374 			rockchip_spi_pio_writer(rs);
375 		}
376 
377 		if (rs->rx) {
378 			remain = rs->rx_end - rs->rx;
379 			rockchip_spi_pio_reader(rs);
380 		}
381 
382 		cpu_relax();
383 	} while (remain);
384 
385 	/* If tx, wait until the FIFO data completely. */
386 	if (rs->tx)
387 		wait_for_idle(rs);
388 
389 	spi_enable_chip(rs, 0);
390 
391 	return 0;
392 }
393 
394 static void rockchip_spi_dma_rxcb(void *data)
395 {
396 	unsigned long flags;
397 	struct rockchip_spi *rs = data;
398 
399 	spin_lock_irqsave(&rs->lock, flags);
400 
401 	rs->state &= ~RXBUSY;
402 	if (!(rs->state & TXBUSY)) {
403 		spi_enable_chip(rs, 0);
404 		spi_finalize_current_transfer(rs->master);
405 	}
406 
407 	spin_unlock_irqrestore(&rs->lock, flags);
408 }
409 
410 static void rockchip_spi_dma_txcb(void *data)
411 {
412 	unsigned long flags;
413 	struct rockchip_spi *rs = data;
414 
415 	/* Wait until the FIFO data completely. */
416 	wait_for_idle(rs);
417 
418 	spin_lock_irqsave(&rs->lock, flags);
419 
420 	rs->state &= ~TXBUSY;
421 	if (!(rs->state & RXBUSY)) {
422 		spi_enable_chip(rs, 0);
423 		spi_finalize_current_transfer(rs->master);
424 	}
425 
426 	spin_unlock_irqrestore(&rs->lock, flags);
427 }
428 
429 static void rockchip_spi_prepare_dma(struct rockchip_spi *rs)
430 {
431 	unsigned long flags;
432 	struct dma_slave_config rxconf, txconf;
433 	struct dma_async_tx_descriptor *rxdesc, *txdesc;
434 
435 	spin_lock_irqsave(&rs->lock, flags);
436 	rs->state &= ~RXBUSY;
437 	rs->state &= ~TXBUSY;
438 	spin_unlock_irqrestore(&rs->lock, flags);
439 
440 	rxdesc = NULL;
441 	if (rs->rx) {
442 		rxconf.direction = rs->dma_rx.direction;
443 		rxconf.src_addr = rs->dma_rx.addr;
444 		rxconf.src_addr_width = rs->n_bytes;
445 		rxconf.src_maxburst = rs->n_bytes;
446 		dmaengine_slave_config(rs->dma_rx.ch, &rxconf);
447 
448 		rxdesc = dmaengine_prep_slave_sg(
449 				rs->dma_rx.ch,
450 				rs->rx_sg.sgl, rs->rx_sg.nents,
451 				rs->dma_rx.direction, DMA_PREP_INTERRUPT);
452 
453 		rxdesc->callback = rockchip_spi_dma_rxcb;
454 		rxdesc->callback_param = rs;
455 	}
456 
457 	txdesc = NULL;
458 	if (rs->tx) {
459 		txconf.direction = rs->dma_tx.direction;
460 		txconf.dst_addr = rs->dma_tx.addr;
461 		txconf.dst_addr_width = rs->n_bytes;
462 		txconf.dst_maxburst = rs->n_bytes;
463 		dmaengine_slave_config(rs->dma_tx.ch, &txconf);
464 
465 		txdesc = dmaengine_prep_slave_sg(
466 				rs->dma_tx.ch,
467 				rs->tx_sg.sgl, rs->tx_sg.nents,
468 				rs->dma_tx.direction, DMA_PREP_INTERRUPT);
469 
470 		txdesc->callback = rockchip_spi_dma_txcb;
471 		txdesc->callback_param = rs;
472 	}
473 
474 	/* rx must be started before tx due to spi instinct */
475 	if (rxdesc) {
476 		spin_lock_irqsave(&rs->lock, flags);
477 		rs->state |= RXBUSY;
478 		spin_unlock_irqrestore(&rs->lock, flags);
479 		dmaengine_submit(rxdesc);
480 		dma_async_issue_pending(rs->dma_rx.ch);
481 	}
482 
483 	if (txdesc) {
484 		spin_lock_irqsave(&rs->lock, flags);
485 		rs->state |= TXBUSY;
486 		spin_unlock_irqrestore(&rs->lock, flags);
487 		dmaengine_submit(txdesc);
488 		dma_async_issue_pending(rs->dma_tx.ch);
489 	}
490 }
491 
492 static void rockchip_spi_config(struct rockchip_spi *rs)
493 {
494 	u32 div = 0;
495 	u32 dmacr = 0;
496 
497 	u32 cr0 = (CR0_BHT_8BIT << CR0_BHT_OFFSET)
498 		| (CR0_SSD_ONE << CR0_SSD_OFFSET);
499 
500 	cr0 |= (rs->n_bytes << CR0_DFS_OFFSET);
501 	cr0 |= ((rs->mode & 0x3) << CR0_SCPH_OFFSET);
502 	cr0 |= (rs->tmode << CR0_XFM_OFFSET);
503 	cr0 |= (rs->type << CR0_FRF_OFFSET);
504 
505 	if (rs->use_dma) {
506 		if (rs->tx)
507 			dmacr |= TF_DMA_EN;
508 		if (rs->rx)
509 			dmacr |= RF_DMA_EN;
510 	}
511 
512 	if (WARN_ON(rs->speed > MAX_SCLK_OUT))
513 		rs->speed = MAX_SCLK_OUT;
514 
515 	/* the minimum divsor is 2 */
516 	if (rs->max_freq < 2 * rs->speed) {
517 		clk_set_rate(rs->spiclk, 2 * rs->speed);
518 		rs->max_freq = clk_get_rate(rs->spiclk);
519 	}
520 
521 	/* div doesn't support odd number */
522 	div = max_t(u32, rs->max_freq / rs->speed, 1);
523 	div = (div + 1) & 0xfffe;
524 
525 	writel_relaxed(cr0, rs->regs + ROCKCHIP_SPI_CTRLR0);
526 
527 	writel_relaxed(rs->len - 1, rs->regs + ROCKCHIP_SPI_CTRLR1);
528 	writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_TXFTLR);
529 	writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_RXFTLR);
530 
531 	writel_relaxed(0, rs->regs + ROCKCHIP_SPI_DMATDLR);
532 	writel_relaxed(0, rs->regs + ROCKCHIP_SPI_DMARDLR);
533 	writel_relaxed(dmacr, rs->regs + ROCKCHIP_SPI_DMACR);
534 
535 	spi_set_clk(rs, div);
536 
537 	dev_dbg(rs->dev, "cr0 0x%x, div %d\n", cr0, div);
538 }
539 
540 static int rockchip_spi_transfer_one(
541 		struct spi_master *master,
542 		struct spi_device *spi,
543 		struct spi_transfer *xfer)
544 {
545 	int ret = 1;
546 	struct rockchip_spi *rs = spi_master_get_devdata(master);
547 
548 	WARN_ON(readl_relaxed(rs->regs + ROCKCHIP_SPI_SSIENR) &&
549 		(readl_relaxed(rs->regs + ROCKCHIP_SPI_SR) & SR_BUSY));
550 
551 	if (!xfer->tx_buf && !xfer->rx_buf) {
552 		dev_err(rs->dev, "No buffer for transfer\n");
553 		return -EINVAL;
554 	}
555 
556 	rs->speed = xfer->speed_hz;
557 	rs->bpw = xfer->bits_per_word;
558 	rs->n_bytes = rs->bpw >> 3;
559 
560 	rs->tx = xfer->tx_buf;
561 	rs->tx_end = rs->tx + xfer->len;
562 	rs->rx = xfer->rx_buf;
563 	rs->rx_end = rs->rx + xfer->len;
564 	rs->len = xfer->len;
565 
566 	rs->tx_sg = xfer->tx_sg;
567 	rs->rx_sg = xfer->rx_sg;
568 
569 	if (rs->tx && rs->rx)
570 		rs->tmode = CR0_XFM_TR;
571 	else if (rs->tx)
572 		rs->tmode = CR0_XFM_TO;
573 	else if (rs->rx)
574 		rs->tmode = CR0_XFM_RO;
575 
576 	/* we need prepare dma before spi was enabled */
577 	if (master->can_dma && master->can_dma(master, spi, xfer))
578 		rs->use_dma = 1;
579 	else
580 		rs->use_dma = 0;
581 
582 	rockchip_spi_config(rs);
583 
584 	if (rs->use_dma) {
585 		if (rs->tmode == CR0_XFM_RO) {
586 			/* rx: dma must be prepared first */
587 			rockchip_spi_prepare_dma(rs);
588 			spi_enable_chip(rs, 1);
589 		} else {
590 			/* tx or tr: spi must be enabled first */
591 			spi_enable_chip(rs, 1);
592 			rockchip_spi_prepare_dma(rs);
593 		}
594 	} else {
595 		spi_enable_chip(rs, 1);
596 		ret = rockchip_spi_pio_transfer(rs);
597 	}
598 
599 	return ret;
600 }
601 
602 static bool rockchip_spi_can_dma(struct spi_master *master,
603 				 struct spi_device *spi,
604 				 struct spi_transfer *xfer)
605 {
606 	struct rockchip_spi *rs = spi_master_get_devdata(master);
607 
608 	return (xfer->len > rs->fifo_len);
609 }
610 
611 static int rockchip_spi_probe(struct platform_device *pdev)
612 {
613 	int ret = 0;
614 	struct rockchip_spi *rs;
615 	struct spi_master *master;
616 	struct resource *mem;
617 
618 	master = spi_alloc_master(&pdev->dev, sizeof(struct rockchip_spi));
619 	if (!master)
620 		return -ENOMEM;
621 
622 	platform_set_drvdata(pdev, master);
623 
624 	rs = spi_master_get_devdata(master);
625 	memset(rs, 0, sizeof(struct rockchip_spi));
626 
627 	/* Get basic io resource and map it */
628 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
629 	rs->regs = devm_ioremap_resource(&pdev->dev, mem);
630 	if (IS_ERR(rs->regs)) {
631 		ret =  PTR_ERR(rs->regs);
632 		goto err_ioremap_resource;
633 	}
634 
635 	rs->apb_pclk = devm_clk_get(&pdev->dev, "apb_pclk");
636 	if (IS_ERR(rs->apb_pclk)) {
637 		dev_err(&pdev->dev, "Failed to get apb_pclk\n");
638 		ret = PTR_ERR(rs->apb_pclk);
639 		goto err_ioremap_resource;
640 	}
641 
642 	rs->spiclk = devm_clk_get(&pdev->dev, "spiclk");
643 	if (IS_ERR(rs->spiclk)) {
644 		dev_err(&pdev->dev, "Failed to get spi_pclk\n");
645 		ret = PTR_ERR(rs->spiclk);
646 		goto err_ioremap_resource;
647 	}
648 
649 	ret = clk_prepare_enable(rs->apb_pclk);
650 	if (ret) {
651 		dev_err(&pdev->dev, "Failed to enable apb_pclk\n");
652 		goto err_ioremap_resource;
653 	}
654 
655 	ret = clk_prepare_enable(rs->spiclk);
656 	if (ret) {
657 		dev_err(&pdev->dev, "Failed to enable spi_clk\n");
658 		goto err_spiclk_enable;
659 	}
660 
661 	spi_enable_chip(rs, 0);
662 
663 	rs->type = SSI_MOTO_SPI;
664 	rs->master = master;
665 	rs->dev = &pdev->dev;
666 	rs->max_freq = clk_get_rate(rs->spiclk);
667 
668 	rs->fifo_len = get_fifo_len(rs);
669 	if (!rs->fifo_len) {
670 		dev_err(&pdev->dev, "Failed to get fifo length\n");
671 		ret = -EINVAL;
672 		goto err_get_fifo_len;
673 	}
674 
675 	spin_lock_init(&rs->lock);
676 
677 	pm_runtime_set_active(&pdev->dev);
678 	pm_runtime_enable(&pdev->dev);
679 
680 	master->auto_runtime_pm = true;
681 	master->bus_num = pdev->id;
682 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LOOP;
683 	master->num_chipselect = 2;
684 	master->dev.of_node = pdev->dev.of_node;
685 	master->bits_per_word_mask = SPI_BPW_MASK(16) | SPI_BPW_MASK(8);
686 
687 	master->set_cs = rockchip_spi_set_cs;
688 	master->prepare_message = rockchip_spi_prepare_message;
689 	master->unprepare_message = rockchip_spi_unprepare_message;
690 	master->transfer_one = rockchip_spi_transfer_one;
691 
692 	rs->dma_tx.ch = dma_request_slave_channel(rs->dev, "tx");
693 	if (!rs->dma_tx.ch)
694 		dev_warn(rs->dev, "Failed to request TX DMA channel\n");
695 
696 	rs->dma_rx.ch = dma_request_slave_channel(rs->dev, "rx");
697 	if (!rs->dma_rx.ch) {
698 		if (rs->dma_tx.ch) {
699 			dma_release_channel(rs->dma_tx.ch);
700 			rs->dma_tx.ch = NULL;
701 		}
702 		dev_warn(rs->dev, "Failed to request RX DMA channel\n");
703 	}
704 
705 	if (rs->dma_tx.ch && rs->dma_rx.ch) {
706 		rs->dma_tx.addr = (dma_addr_t)(mem->start + ROCKCHIP_SPI_TXDR);
707 		rs->dma_rx.addr = (dma_addr_t)(mem->start + ROCKCHIP_SPI_RXDR);
708 		rs->dma_tx.direction = DMA_MEM_TO_DEV;
709 		rs->dma_rx.direction = DMA_DEV_TO_MEM;
710 
711 		master->can_dma = rockchip_spi_can_dma;
712 		master->dma_tx = rs->dma_tx.ch;
713 		master->dma_rx = rs->dma_rx.ch;
714 	}
715 
716 	ret = devm_spi_register_master(&pdev->dev, master);
717 	if (ret) {
718 		dev_err(&pdev->dev, "Failed to register master\n");
719 		goto err_register_master;
720 	}
721 
722 	return 0;
723 
724 err_register_master:
725 	if (rs->dma_tx.ch)
726 		dma_release_channel(rs->dma_tx.ch);
727 	if (rs->dma_rx.ch)
728 		dma_release_channel(rs->dma_rx.ch);
729 err_get_fifo_len:
730 	clk_disable_unprepare(rs->spiclk);
731 err_spiclk_enable:
732 	clk_disable_unprepare(rs->apb_pclk);
733 err_ioremap_resource:
734 	spi_master_put(master);
735 
736 	return ret;
737 }
738 
739 static int rockchip_spi_remove(struct platform_device *pdev)
740 {
741 	struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
742 	struct rockchip_spi *rs = spi_master_get_devdata(master);
743 
744 	pm_runtime_disable(&pdev->dev);
745 
746 	clk_disable_unprepare(rs->spiclk);
747 	clk_disable_unprepare(rs->apb_pclk);
748 
749 	if (rs->dma_tx.ch)
750 		dma_release_channel(rs->dma_tx.ch);
751 	if (rs->dma_rx.ch)
752 		dma_release_channel(rs->dma_rx.ch);
753 
754 	return 0;
755 }
756 
757 #ifdef CONFIG_PM_SLEEP
758 static int rockchip_spi_suspend(struct device *dev)
759 {
760 	int ret = 0;
761 	struct spi_master *master = dev_get_drvdata(dev);
762 	struct rockchip_spi *rs = spi_master_get_devdata(master);
763 
764 	ret = spi_master_suspend(rs->master);
765 	if (ret)
766 		return ret;
767 
768 	if (!pm_runtime_suspended(dev)) {
769 		clk_disable_unprepare(rs->spiclk);
770 		clk_disable_unprepare(rs->apb_pclk);
771 	}
772 
773 	return ret;
774 }
775 
776 static int rockchip_spi_resume(struct device *dev)
777 {
778 	int ret = 0;
779 	struct spi_master *master = dev_get_drvdata(dev);
780 	struct rockchip_spi *rs = spi_master_get_devdata(master);
781 
782 	if (!pm_runtime_suspended(dev)) {
783 		ret = clk_prepare_enable(rs->apb_pclk);
784 		if (ret < 0)
785 			return ret;
786 
787 		ret = clk_prepare_enable(rs->spiclk);
788 		if (ret < 0) {
789 			clk_disable_unprepare(rs->apb_pclk);
790 			return ret;
791 		}
792 	}
793 
794 	ret = spi_master_resume(rs->master);
795 	if (ret < 0) {
796 		clk_disable_unprepare(rs->spiclk);
797 		clk_disable_unprepare(rs->apb_pclk);
798 	}
799 
800 	return ret;
801 }
802 #endif /* CONFIG_PM_SLEEP */
803 
804 #ifdef CONFIG_PM
805 static int rockchip_spi_runtime_suspend(struct device *dev)
806 {
807 	struct spi_master *master = dev_get_drvdata(dev);
808 	struct rockchip_spi *rs = spi_master_get_devdata(master);
809 
810 	clk_disable_unprepare(rs->spiclk);
811 	clk_disable_unprepare(rs->apb_pclk);
812 
813 	return 0;
814 }
815 
816 static int rockchip_spi_runtime_resume(struct device *dev)
817 {
818 	int ret;
819 	struct spi_master *master = dev_get_drvdata(dev);
820 	struct rockchip_spi *rs = spi_master_get_devdata(master);
821 
822 	ret = clk_prepare_enable(rs->apb_pclk);
823 	if (ret)
824 		return ret;
825 
826 	ret = clk_prepare_enable(rs->spiclk);
827 	if (ret)
828 		clk_disable_unprepare(rs->apb_pclk);
829 
830 	return ret;
831 }
832 #endif /* CONFIG_PM */
833 
834 static const struct dev_pm_ops rockchip_spi_pm = {
835 	SET_SYSTEM_SLEEP_PM_OPS(rockchip_spi_suspend, rockchip_spi_resume)
836 	SET_RUNTIME_PM_OPS(rockchip_spi_runtime_suspend,
837 			   rockchip_spi_runtime_resume, NULL)
838 };
839 
840 static const struct of_device_id rockchip_spi_dt_match[] = {
841 	{ .compatible = "rockchip,rk3066-spi", },
842 	{ .compatible = "rockchip,rk3188-spi", },
843 	{ .compatible = "rockchip,rk3288-spi", },
844 	{ },
845 };
846 MODULE_DEVICE_TABLE(of, rockchip_spi_dt_match);
847 
848 static struct platform_driver rockchip_spi_driver = {
849 	.driver = {
850 		.name	= DRIVER_NAME,
851 		.pm = &rockchip_spi_pm,
852 		.of_match_table = of_match_ptr(rockchip_spi_dt_match),
853 	},
854 	.probe = rockchip_spi_probe,
855 	.remove = rockchip_spi_remove,
856 };
857 
858 module_platform_driver(rockchip_spi_driver);
859 
860 MODULE_AUTHOR("Addy Ke <addy.ke@rock-chips.com>");
861 MODULE_DESCRIPTION("ROCKCHIP SPI Controller Driver");
862 MODULE_LICENSE("GPL v2");
863