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  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/clk.h>
 17#include <linux/dmaengine.h>
 18#include <linux/module.h>
 19#include <linux/of.h>
 20#include <linux/platform_device.h>
 21#include <linux/spi/spi.h>
 22#include <linux/pm_runtime.h>
 23#include <linux/scatterlist.h>
 24
 25#define DRIVER_NAME "rockchip-spi"
 26
 27/* SPI register offsets */
 28#define ROCKCHIP_SPI_CTRLR0			0x0000
 29#define ROCKCHIP_SPI_CTRLR1			0x0004
 30#define ROCKCHIP_SPI_SSIENR			0x0008
 31#define ROCKCHIP_SPI_SER			0x000c
 32#define ROCKCHIP_SPI_BAUDR			0x0010
 33#define ROCKCHIP_SPI_TXFTLR			0x0014
 34#define ROCKCHIP_SPI_RXFTLR			0x0018
 35#define ROCKCHIP_SPI_TXFLR			0x001c
 36#define ROCKCHIP_SPI_RXFLR			0x0020
 37#define ROCKCHIP_SPI_SR				0x0024
 38#define ROCKCHIP_SPI_IPR			0x0028
 39#define ROCKCHIP_SPI_IMR			0x002c
 40#define ROCKCHIP_SPI_ISR			0x0030
 41#define ROCKCHIP_SPI_RISR			0x0034
 42#define ROCKCHIP_SPI_ICR			0x0038
 43#define ROCKCHIP_SPI_DMACR			0x003c
 44#define ROCKCHIP_SPI_DMATDLR		0x0040
 45#define ROCKCHIP_SPI_DMARDLR		0x0044
 46#define ROCKCHIP_SPI_TXDR			0x0400
 47#define ROCKCHIP_SPI_RXDR			0x0800
 48
 49/* Bit fields in CTRLR0 */
 50#define CR0_DFS_OFFSET				0
 51
 52#define CR0_CFS_OFFSET				2
 53
 54#define CR0_SCPH_OFFSET				6
 55
 56#define CR0_SCPOL_OFFSET			7
 57
 58#define CR0_CSM_OFFSET				8
 59#define CR0_CSM_KEEP				0x0
 60/* ss_n be high for half sclk_out cycles */
 61#define CR0_CSM_HALF				0X1
 62/* ss_n be high for one sclk_out cycle */
 63#define CR0_CSM_ONE					0x2
 64
 65/* ss_n to sclk_out delay */
 66#define CR0_SSD_OFFSET				10
 67/*
 68 * The period between ss_n active and
 69 * sclk_out active is half sclk_out cycles
 70 */
 71#define CR0_SSD_HALF				0x0
 72/*
 73 * The period between ss_n active and
 74 * sclk_out active is one sclk_out cycle
 75 */
 76#define CR0_SSD_ONE					0x1
 77
 78#define CR0_EM_OFFSET				11
 79#define CR0_EM_LITTLE				0x0
 80#define CR0_EM_BIG					0x1
 81
 82#define CR0_FBM_OFFSET				12
 83#define CR0_FBM_MSB					0x0
 84#define CR0_FBM_LSB					0x1
 85
 86#define CR0_BHT_OFFSET				13
 87#define CR0_BHT_16BIT				0x0
 88#define CR0_BHT_8BIT				0x1
 89
 90#define CR0_RSD_OFFSET				14
 91
 92#define CR0_FRF_OFFSET				16
 93#define CR0_FRF_SPI					0x0
 94#define CR0_FRF_SSP					0x1
 95#define CR0_FRF_MICROWIRE			0x2
 96
 97#define CR0_XFM_OFFSET				18
 98#define CR0_XFM_MASK				(0x03 << SPI_XFM_OFFSET)
 99#define CR0_XFM_TR					0x0
100#define CR0_XFM_TO					0x1
101#define CR0_XFM_RO					0x2
102
103#define CR0_OPM_OFFSET				20
104#define CR0_OPM_MASTER				0x0
105#define CR0_OPM_SLAVE				0x1
106
107#define CR0_MTM_OFFSET				0x21
108
109/* Bit fields in SER, 2bit */
110#define SER_MASK					0x3
111
112/* Bit fields in SR, 5bit */
113#define SR_MASK						0x1f
114#define SR_BUSY						(1 << 0)
115#define SR_TF_FULL					(1 << 1)
116#define SR_TF_EMPTY					(1 << 2)
117#define SR_RF_EMPTY					(1 << 3)
118#define SR_RF_FULL					(1 << 4)
119
120/* Bit fields in ISR, IMR, ISR, RISR, 5bit */
121#define INT_MASK					0x1f
122#define INT_TF_EMPTY				(1 << 0)
123#define INT_TF_OVERFLOW				(1 << 1)
124#define INT_RF_UNDERFLOW			(1 << 2)
125#define INT_RF_OVERFLOW				(1 << 3)
126#define INT_RF_FULL					(1 << 4)
127
128/* Bit fields in ICR, 4bit */
129#define ICR_MASK					0x0f
130#define ICR_ALL						(1 << 0)
131#define ICR_RF_UNDERFLOW			(1 << 1)
132#define ICR_RF_OVERFLOW				(1 << 2)
133#define ICR_TF_OVERFLOW				(1 << 3)
134
135/* Bit fields in DMACR */
136#define RF_DMA_EN					(1 << 0)
137#define TF_DMA_EN					(1 << 1)
138
139#define RXBUSY						(1 << 0)
140#define TXBUSY						(1 << 1)
141
142/* sclk_out: spi master internal logic in rk3x can support 50Mhz */
143#define MAX_SCLK_OUT		50000000
144
145/*
146 * SPI_CTRLR1 is 16-bits, so we should support lengths of 0xffff + 1. However,
147 * the controller seems to hang when given 0x10000, so stick with this for now.
148 */
149#define ROCKCHIP_SPI_MAX_TRANLEN		0xffff
150
151enum rockchip_ssi_type {
152	SSI_MOTO_SPI = 0,
153	SSI_TI_SSP,
154	SSI_NS_MICROWIRE,
155};
156
157struct rockchip_spi_dma_data {
158	struct dma_chan *ch;
159	enum dma_transfer_direction direction;
160	dma_addr_t addr;
161};
162
163struct 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	u32 rsd_nsecs;
183	unsigned len;
184	u32 speed;
185
186	const void *tx;
187	const void *tx_end;
188	void *rx;
189	void *rx_end;
190
191	u32 state;
192	/* protect state */
193	spinlock_t lock;
194
195	u32 use_dma;
196	struct sg_table tx_sg;
197	struct sg_table rx_sg;
198	struct rockchip_spi_dma_data dma_rx;
199	struct rockchip_spi_dma_data dma_tx;
200	struct dma_slave_caps dma_caps;
201};
202
203static 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
208static inline void spi_set_clk(struct rockchip_spi *rs, u16 div)
209{
210	writel_relaxed(div, rs->regs + ROCKCHIP_SPI_BAUDR);
211}
212
213static 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
219static 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
231static 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
246static 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
256static 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
264static void rockchip_spi_set_cs(struct spi_device *spi, bool enable)
265{
266	u32 ser;
267	struct spi_master *master = spi->master;
268	struct rockchip_spi *rs = spi_master_get_devdata(master);
269
270	pm_runtime_get_sync(rs->dev);
271
272	ser = readl_relaxed(rs->regs + ROCKCHIP_SPI_SER) & SER_MASK;
273
274	/*
275	 * drivers/spi/spi.c:
276	 * static void spi_set_cs(struct spi_device *spi, bool enable)
277	 * {
278	 *		if (spi->mode & SPI_CS_HIGH)
279	 *			enable = !enable;
280	 *
281	 *		if (spi->cs_gpio >= 0)
282	 *			gpio_set_value(spi->cs_gpio, !enable);
283	 *		else if (spi->master->set_cs)
284	 *		spi->master->set_cs(spi, !enable);
285	 * }
286	 *
287	 * Note: enable(rockchip_spi_set_cs) = !enable(spi_set_cs)
288	 */
289	if (!enable)
290		ser |= 1 << spi->chip_select;
291	else
292		ser &= ~(1 << spi->chip_select);
293
294	writel_relaxed(ser, rs->regs + ROCKCHIP_SPI_SER);
295
296	pm_runtime_put_sync(rs->dev);
297}
298
299static int rockchip_spi_prepare_message(struct spi_master *master,
300					struct spi_message *msg)
301{
302	struct rockchip_spi *rs = spi_master_get_devdata(master);
303	struct spi_device *spi = msg->spi;
304
305	rs->mode = spi->mode;
306
307	return 0;
308}
309
310static void rockchip_spi_handle_err(struct spi_master *master,
311				    struct spi_message *msg)
312{
313	unsigned long flags;
314	struct rockchip_spi *rs = spi_master_get_devdata(master);
315
316	spin_lock_irqsave(&rs->lock, flags);
317
318	/*
319	 * For DMA mode, we need terminate DMA channel and flush
320	 * fifo for the next transfer if DMA thansfer timeout.
321	 * handle_err() was called by core if transfer failed.
322	 * Maybe it is reasonable for error handling here.
323	 */
324	if (rs->use_dma) {
325		if (rs->state & RXBUSY) {
326			dmaengine_terminate_async(rs->dma_rx.ch);
327			flush_fifo(rs);
328		}
329
330		if (rs->state & TXBUSY)
331			dmaengine_terminate_async(rs->dma_tx.ch);
332	}
333
334	spin_unlock_irqrestore(&rs->lock, flags);
335}
336
337static int rockchip_spi_unprepare_message(struct spi_master *master,
338					  struct spi_message *msg)
339{
340	struct rockchip_spi *rs = spi_master_get_devdata(master);
341
342	spi_enable_chip(rs, 0);
343
344	return 0;
345}
346
347static void rockchip_spi_pio_writer(struct rockchip_spi *rs)
348{
349	u32 max = tx_max(rs);
350	u32 txw = 0;
351
352	while (max--) {
353		if (rs->n_bytes == 1)
354			txw = *(u8 *)(rs->tx);
355		else
356			txw = *(u16 *)(rs->tx);
357
358		writel_relaxed(txw, rs->regs + ROCKCHIP_SPI_TXDR);
359		rs->tx += rs->n_bytes;
360	}
361}
362
363static void rockchip_spi_pio_reader(struct rockchip_spi *rs)
364{
365	u32 max = rx_max(rs);
366	u32 rxw;
367
368	while (max--) {
369		rxw = readl_relaxed(rs->regs + ROCKCHIP_SPI_RXDR);
370		if (rs->n_bytes == 1)
371			*(u8 *)(rs->rx) = (u8)rxw;
372		else
373			*(u16 *)(rs->rx) = (u16)rxw;
374		rs->rx += rs->n_bytes;
375	}
376}
377
378static int rockchip_spi_pio_transfer(struct rockchip_spi *rs)
379{
380	int remain = 0;
381
382	do {
383		if (rs->tx) {
384			remain = rs->tx_end - rs->tx;
385			rockchip_spi_pio_writer(rs);
386		}
387
388		if (rs->rx) {
389			remain = rs->rx_end - rs->rx;
390			rockchip_spi_pio_reader(rs);
391		}
392
393		cpu_relax();
394	} while (remain);
395
396	/* If tx, wait until the FIFO data completely. */
397	if (rs->tx)
398		wait_for_idle(rs);
399
400	spi_enable_chip(rs, 0);
401
402	return 0;
403}
404
405static void rockchip_spi_dma_rxcb(void *data)
406{
407	unsigned long flags;
408	struct rockchip_spi *rs = data;
409
410	spin_lock_irqsave(&rs->lock, flags);
411
412	rs->state &= ~RXBUSY;
413	if (!(rs->state & TXBUSY)) {
414		spi_enable_chip(rs, 0);
415		spi_finalize_current_transfer(rs->master);
416	}
417
418	spin_unlock_irqrestore(&rs->lock, flags);
419}
420
421static void rockchip_spi_dma_txcb(void *data)
422{
423	unsigned long flags;
424	struct rockchip_spi *rs = data;
425
426	/* Wait until the FIFO data completely. */
427	wait_for_idle(rs);
428
429	spin_lock_irqsave(&rs->lock, flags);
430
431	rs->state &= ~TXBUSY;
432	if (!(rs->state & RXBUSY)) {
433		spi_enable_chip(rs, 0);
434		spi_finalize_current_transfer(rs->master);
435	}
436
437	spin_unlock_irqrestore(&rs->lock, flags);
438}
439
440static int rockchip_spi_prepare_dma(struct rockchip_spi *rs)
441{
442	unsigned long flags;
443	struct dma_slave_config rxconf, txconf;
444	struct dma_async_tx_descriptor *rxdesc, *txdesc;
445
446	spin_lock_irqsave(&rs->lock, flags);
447	rs->state &= ~RXBUSY;
448	rs->state &= ~TXBUSY;
449	spin_unlock_irqrestore(&rs->lock, flags);
450
451	rxdesc = NULL;
452	if (rs->rx) {
453		rxconf.direction = rs->dma_rx.direction;
454		rxconf.src_addr = rs->dma_rx.addr;
455		rxconf.src_addr_width = rs->n_bytes;
456		if (rs->dma_caps.max_burst > 4)
457			rxconf.src_maxburst = 4;
458		else
459			rxconf.src_maxburst = 1;
460		dmaengine_slave_config(rs->dma_rx.ch, &rxconf);
461
462		rxdesc = dmaengine_prep_slave_sg(
463				rs->dma_rx.ch,
464				rs->rx_sg.sgl, rs->rx_sg.nents,
465				rs->dma_rx.direction, DMA_PREP_INTERRUPT);
466		if (!rxdesc)
467			return -EINVAL;
468
469		rxdesc->callback = rockchip_spi_dma_rxcb;
470		rxdesc->callback_param = rs;
471	}
472
473	txdesc = NULL;
474	if (rs->tx) {
475		txconf.direction = rs->dma_tx.direction;
476		txconf.dst_addr = rs->dma_tx.addr;
477		txconf.dst_addr_width = rs->n_bytes;
478		if (rs->dma_caps.max_burst > 4)
479			txconf.dst_maxburst = 4;
480		else
481			txconf.dst_maxburst = 1;
482		dmaengine_slave_config(rs->dma_tx.ch, &txconf);
483
484		txdesc = dmaengine_prep_slave_sg(
485				rs->dma_tx.ch,
486				rs->tx_sg.sgl, rs->tx_sg.nents,
487				rs->dma_tx.direction, DMA_PREP_INTERRUPT);
488		if (!txdesc) {
489			if (rxdesc)
490				dmaengine_terminate_sync(rs->dma_rx.ch);
491			return -EINVAL;
492		}
493
494		txdesc->callback = rockchip_spi_dma_txcb;
495		txdesc->callback_param = rs;
496	}
497
498	/* rx must be started before tx due to spi instinct */
499	if (rxdesc) {
500		spin_lock_irqsave(&rs->lock, flags);
501		rs->state |= RXBUSY;
502		spin_unlock_irqrestore(&rs->lock, flags);
503		dmaengine_submit(rxdesc);
504		dma_async_issue_pending(rs->dma_rx.ch);
505	}
506
507	if (txdesc) {
508		spin_lock_irqsave(&rs->lock, flags);
509		rs->state |= TXBUSY;
510		spin_unlock_irqrestore(&rs->lock, flags);
511		dmaengine_submit(txdesc);
512		dma_async_issue_pending(rs->dma_tx.ch);
513	}
514
515	return 0;
516}
517
518static void rockchip_spi_config(struct rockchip_spi *rs)
519{
520	u32 div = 0;
521	u32 dmacr = 0;
522	int rsd = 0;
523
524	u32 cr0 = (CR0_BHT_8BIT << CR0_BHT_OFFSET)
525		| (CR0_SSD_ONE << CR0_SSD_OFFSET)
526		| (CR0_EM_BIG << CR0_EM_OFFSET);
527
528	cr0 |= (rs->n_bytes << CR0_DFS_OFFSET);
529	cr0 |= ((rs->mode & 0x3) << CR0_SCPH_OFFSET);
530	cr0 |= (rs->tmode << CR0_XFM_OFFSET);
531	cr0 |= (rs->type << CR0_FRF_OFFSET);
532
533	if (rs->use_dma) {
534		if (rs->tx)
535			dmacr |= TF_DMA_EN;
536		if (rs->rx)
537			dmacr |= RF_DMA_EN;
538	}
539
540	if (WARN_ON(rs->speed > MAX_SCLK_OUT))
541		rs->speed = MAX_SCLK_OUT;
542
543	/* the minimum divisor is 2 */
544	if (rs->max_freq < 2 * rs->speed) {
545		clk_set_rate(rs->spiclk, 2 * rs->speed);
546		rs->max_freq = clk_get_rate(rs->spiclk);
547	}
548
549	/* div doesn't support odd number */
550	div = DIV_ROUND_UP(rs->max_freq, rs->speed);
551	div = (div + 1) & 0xfffe;
552
553	/* Rx sample delay is expressed in parent clock cycles (max 3) */
554	rsd = DIV_ROUND_CLOSEST(rs->rsd_nsecs * (rs->max_freq >> 8),
555				1000000000 >> 8);
556	if (!rsd && rs->rsd_nsecs) {
557		pr_warn_once("rockchip-spi: %u Hz are too slow to express %u ns delay\n",
558			     rs->max_freq, rs->rsd_nsecs);
559	} else if (rsd > 3) {
560		rsd = 3;
561		pr_warn_once("rockchip-spi: %u Hz are too fast to express %u ns delay, clamping at %u ns\n",
562			     rs->max_freq, rs->rsd_nsecs,
563			     rsd * 1000000000U / rs->max_freq);
564	}
565	cr0 |= rsd << CR0_RSD_OFFSET;
566
567	writel_relaxed(cr0, rs->regs + ROCKCHIP_SPI_CTRLR0);
568
569	writel_relaxed(rs->len - 1, rs->regs + ROCKCHIP_SPI_CTRLR1);
570	writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_TXFTLR);
571	writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_RXFTLR);
572
573	writel_relaxed(0, rs->regs + ROCKCHIP_SPI_DMATDLR);
574	writel_relaxed(0, rs->regs + ROCKCHIP_SPI_DMARDLR);
575	writel_relaxed(dmacr, rs->regs + ROCKCHIP_SPI_DMACR);
576
577	spi_set_clk(rs, div);
578
579	dev_dbg(rs->dev, "cr0 0x%x, div %d\n", cr0, div);
580}
581
582static size_t rockchip_spi_max_transfer_size(struct spi_device *spi)
583{
584	return ROCKCHIP_SPI_MAX_TRANLEN;
585}
586
587static int rockchip_spi_transfer_one(
588		struct spi_master *master,
589		struct spi_device *spi,
590		struct spi_transfer *xfer)
591{
592	int ret = 0;
593	struct rockchip_spi *rs = spi_master_get_devdata(master);
594
595	WARN_ON(readl_relaxed(rs->regs + ROCKCHIP_SPI_SSIENR) &&
596		(readl_relaxed(rs->regs + ROCKCHIP_SPI_SR) & SR_BUSY));
597
598	if (!xfer->tx_buf && !xfer->rx_buf) {
599		dev_err(rs->dev, "No buffer for transfer\n");
600		return -EINVAL;
601	}
602
603	if (xfer->len > ROCKCHIP_SPI_MAX_TRANLEN) {
604		dev_err(rs->dev, "Transfer is too long (%d)\n", xfer->len);
605		return -EINVAL;
606	}
607
608	rs->speed = xfer->speed_hz;
609	rs->bpw = xfer->bits_per_word;
610	rs->n_bytes = rs->bpw >> 3;
611
612	rs->tx = xfer->tx_buf;
613	rs->tx_end = rs->tx + xfer->len;
614	rs->rx = xfer->rx_buf;
615	rs->rx_end = rs->rx + xfer->len;
616	rs->len = xfer->len;
617
618	rs->tx_sg = xfer->tx_sg;
619	rs->rx_sg = xfer->rx_sg;
620
621	if (rs->tx && rs->rx)
622		rs->tmode = CR0_XFM_TR;
623	else if (rs->tx)
624		rs->tmode = CR0_XFM_TO;
625	else if (rs->rx)
626		rs->tmode = CR0_XFM_RO;
627
628	/* we need prepare dma before spi was enabled */
629	if (master->can_dma && master->can_dma(master, spi, xfer))
630		rs->use_dma = 1;
631	else
632		rs->use_dma = 0;
633
634	rockchip_spi_config(rs);
635
636	if (rs->use_dma) {
637		if (rs->tmode == CR0_XFM_RO) {
638			/* rx: dma must be prepared first */
639			ret = rockchip_spi_prepare_dma(rs);
640			spi_enable_chip(rs, 1);
641		} else {
642			/* tx or tr: spi must be enabled first */
643			spi_enable_chip(rs, 1);
644			ret = rockchip_spi_prepare_dma(rs);
645		}
646		/* successful DMA prepare means the transfer is in progress */
647		ret = ret ? ret : 1;
648	} else {
649		spi_enable_chip(rs, 1);
650		ret = rockchip_spi_pio_transfer(rs);
651	}
652
653	return ret;
654}
655
656static bool rockchip_spi_can_dma(struct spi_master *master,
657				 struct spi_device *spi,
658				 struct spi_transfer *xfer)
659{
660	struct rockchip_spi *rs = spi_master_get_devdata(master);
661
662	return (xfer->len > rs->fifo_len);
663}
664
665static int rockchip_spi_probe(struct platform_device *pdev)
666{
667	int ret = 0;
668	struct rockchip_spi *rs;
669	struct spi_master *master;
670	struct resource *mem;
671	u32 rsd_nsecs;
672
673	master = spi_alloc_master(&pdev->dev, sizeof(struct rockchip_spi));
674	if (!master)
675		return -ENOMEM;
676
677	platform_set_drvdata(pdev, master);
678
679	rs = spi_master_get_devdata(master);
680
681	/* Get basic io resource and map it */
682	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
683	rs->regs = devm_ioremap_resource(&pdev->dev, mem);
684	if (IS_ERR(rs->regs)) {
685		ret =  PTR_ERR(rs->regs);
686		goto err_ioremap_resource;
687	}
688
689	rs->apb_pclk = devm_clk_get(&pdev->dev, "apb_pclk");
690	if (IS_ERR(rs->apb_pclk)) {
691		dev_err(&pdev->dev, "Failed to get apb_pclk\n");
692		ret = PTR_ERR(rs->apb_pclk);
693		goto err_ioremap_resource;
694	}
695
696	rs->spiclk = devm_clk_get(&pdev->dev, "spiclk");
697	if (IS_ERR(rs->spiclk)) {
698		dev_err(&pdev->dev, "Failed to get spi_pclk\n");
699		ret = PTR_ERR(rs->spiclk);
700		goto err_ioremap_resource;
701	}
702
703	ret = clk_prepare_enable(rs->apb_pclk);
704	if (ret) {
705		dev_err(&pdev->dev, "Failed to enable apb_pclk\n");
706		goto err_ioremap_resource;
707	}
708
709	ret = clk_prepare_enable(rs->spiclk);
710	if (ret) {
711		dev_err(&pdev->dev, "Failed to enable spi_clk\n");
712		goto err_spiclk_enable;
713	}
714
715	spi_enable_chip(rs, 0);
716
717	rs->type = SSI_MOTO_SPI;
718	rs->master = master;
719	rs->dev = &pdev->dev;
720	rs->max_freq = clk_get_rate(rs->spiclk);
721
722	if (!of_property_read_u32(pdev->dev.of_node, "rx-sample-delay-ns",
723				  &rsd_nsecs))
724		rs->rsd_nsecs = rsd_nsecs;
725
726	rs->fifo_len = get_fifo_len(rs);
727	if (!rs->fifo_len) {
728		dev_err(&pdev->dev, "Failed to get fifo length\n");
729		ret = -EINVAL;
730		goto err_get_fifo_len;
731	}
732
733	spin_lock_init(&rs->lock);
734
735	pm_runtime_set_active(&pdev->dev);
736	pm_runtime_enable(&pdev->dev);
737
738	master->auto_runtime_pm = true;
739	master->bus_num = pdev->id;
740	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LOOP;
741	master->num_chipselect = 2;
742	master->dev.of_node = pdev->dev.of_node;
743	master->bits_per_word_mask = SPI_BPW_MASK(16) | SPI_BPW_MASK(8);
744
745	master->set_cs = rockchip_spi_set_cs;
746	master->prepare_message = rockchip_spi_prepare_message;
747	master->unprepare_message = rockchip_spi_unprepare_message;
748	master->transfer_one = rockchip_spi_transfer_one;
749	master->max_transfer_size = rockchip_spi_max_transfer_size;
750	master->handle_err = rockchip_spi_handle_err;
751
752	rs->dma_tx.ch = dma_request_chan(rs->dev, "tx");
753	if (IS_ERR(rs->dma_tx.ch)) {
754		/* Check tx to see if we need defer probing driver */
755		if (PTR_ERR(rs->dma_tx.ch) == -EPROBE_DEFER) {
756			ret = -EPROBE_DEFER;
757			goto err_get_fifo_len;
758		}
759		dev_warn(rs->dev, "Failed to request TX DMA channel\n");
760		rs->dma_tx.ch = NULL;
761	}
762
763	rs->dma_rx.ch = dma_request_chan(rs->dev, "rx");
764	if (IS_ERR(rs->dma_rx.ch)) {
765		if (PTR_ERR(rs->dma_rx.ch) == -EPROBE_DEFER) {
766			ret = -EPROBE_DEFER;
767			goto err_free_dma_tx;
768		}
769		dev_warn(rs->dev, "Failed to request RX DMA channel\n");
770		rs->dma_rx.ch = NULL;
771	}
772
773	if (rs->dma_tx.ch && rs->dma_rx.ch) {
774		dma_get_slave_caps(rs->dma_rx.ch, &(rs->dma_caps));
775		rs->dma_tx.addr = (dma_addr_t)(mem->start + ROCKCHIP_SPI_TXDR);
776		rs->dma_rx.addr = (dma_addr_t)(mem->start + ROCKCHIP_SPI_RXDR);
777		rs->dma_tx.direction = DMA_MEM_TO_DEV;
778		rs->dma_rx.direction = DMA_DEV_TO_MEM;
779
780		master->can_dma = rockchip_spi_can_dma;
781		master->dma_tx = rs->dma_tx.ch;
782		master->dma_rx = rs->dma_rx.ch;
783	}
784
785	ret = devm_spi_register_master(&pdev->dev, master);
786	if (ret) {
787		dev_err(&pdev->dev, "Failed to register master\n");
788		goto err_register_master;
789	}
790
791	return 0;
792
793err_register_master:
794	pm_runtime_disable(&pdev->dev);
795	if (rs->dma_rx.ch)
796		dma_release_channel(rs->dma_rx.ch);
797err_free_dma_tx:
798	if (rs->dma_tx.ch)
799		dma_release_channel(rs->dma_tx.ch);
800err_get_fifo_len:
801	clk_disable_unprepare(rs->spiclk);
802err_spiclk_enable:
803	clk_disable_unprepare(rs->apb_pclk);
804err_ioremap_resource:
805	spi_master_put(master);
806
807	return ret;
808}
809
810static int rockchip_spi_remove(struct platform_device *pdev)
811{
812	struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
813	struct rockchip_spi *rs = spi_master_get_devdata(master);
814
815	pm_runtime_disable(&pdev->dev);
816
817	clk_disable_unprepare(rs->spiclk);
818	clk_disable_unprepare(rs->apb_pclk);
819
820	if (rs->dma_tx.ch)
821		dma_release_channel(rs->dma_tx.ch);
822	if (rs->dma_rx.ch)
823		dma_release_channel(rs->dma_rx.ch);
824
825	spi_master_put(master);
826
827	return 0;
828}
829
830#ifdef CONFIG_PM_SLEEP
831static int rockchip_spi_suspend(struct device *dev)
832{
833	int ret = 0;
834	struct spi_master *master = dev_get_drvdata(dev);
835	struct rockchip_spi *rs = spi_master_get_devdata(master);
836
837	ret = spi_master_suspend(rs->master);
838	if (ret)
839		return ret;
840
841	if (!pm_runtime_suspended(dev)) {
842		clk_disable_unprepare(rs->spiclk);
843		clk_disable_unprepare(rs->apb_pclk);
844	}
845
846	return ret;
847}
848
849static int rockchip_spi_resume(struct device *dev)
850{
851	int ret = 0;
852	struct spi_master *master = dev_get_drvdata(dev);
853	struct rockchip_spi *rs = spi_master_get_devdata(master);
854
855	if (!pm_runtime_suspended(dev)) {
856		ret = clk_prepare_enable(rs->apb_pclk);
857		if (ret < 0)
858			return ret;
859
860		ret = clk_prepare_enable(rs->spiclk);
861		if (ret < 0) {
862			clk_disable_unprepare(rs->apb_pclk);
863			return ret;
864		}
865	}
866
867	ret = spi_master_resume(rs->master);
868	if (ret < 0) {
869		clk_disable_unprepare(rs->spiclk);
870		clk_disable_unprepare(rs->apb_pclk);
871	}
872
873	return ret;
874}
875#endif /* CONFIG_PM_SLEEP */
876
877#ifdef CONFIG_PM
878static int rockchip_spi_runtime_suspend(struct device *dev)
879{
880	struct spi_master *master = dev_get_drvdata(dev);
881	struct rockchip_spi *rs = spi_master_get_devdata(master);
882
883	clk_disable_unprepare(rs->spiclk);
884	clk_disable_unprepare(rs->apb_pclk);
885
886	return 0;
887}
888
889static int rockchip_spi_runtime_resume(struct device *dev)
890{
891	int ret;
892	struct spi_master *master = dev_get_drvdata(dev);
893	struct rockchip_spi *rs = spi_master_get_devdata(master);
894
895	ret = clk_prepare_enable(rs->apb_pclk);
896	if (ret)
897		return ret;
898
899	ret = clk_prepare_enable(rs->spiclk);
900	if (ret)
901		clk_disable_unprepare(rs->apb_pclk);
902
903	return ret;
904}
905#endif /* CONFIG_PM */
906
907static const struct dev_pm_ops rockchip_spi_pm = {
908	SET_SYSTEM_SLEEP_PM_OPS(rockchip_spi_suspend, rockchip_spi_resume)
909	SET_RUNTIME_PM_OPS(rockchip_spi_runtime_suspend,
910			   rockchip_spi_runtime_resume, NULL)
911};
912
913static const struct of_device_id rockchip_spi_dt_match[] = {
914	{ .compatible = "rockchip,rk3036-spi", },
915	{ .compatible = "rockchip,rk3066-spi", },
916	{ .compatible = "rockchip,rk3188-spi", },
917	{ .compatible = "rockchip,rk3228-spi", },
918	{ .compatible = "rockchip,rk3288-spi", },
919	{ .compatible = "rockchip,rk3368-spi", },
920	{ .compatible = "rockchip,rk3399-spi", },
921	{ },
922};
923MODULE_DEVICE_TABLE(of, rockchip_spi_dt_match);
924
925static struct platform_driver rockchip_spi_driver = {
926	.driver = {
927		.name	= DRIVER_NAME,
928		.pm = &rockchip_spi_pm,
929		.of_match_table = of_match_ptr(rockchip_spi_dt_match),
930	},
931	.probe = rockchip_spi_probe,
932	.remove = rockchip_spi_remove,
933};
934
935module_platform_driver(rockchip_spi_driver);
936
937MODULE_AUTHOR("Addy Ke <addy.ke@rock-chips.com>");
938MODULE_DESCRIPTION("ROCKCHIP SPI Controller Driver");
939MODULE_LICENSE("GPL v2");