xref: /kernel/linux/linux-5.10/drivers/spi/spi-rspi.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * SH RSPI driver
4 *
5 * Copyright (C) 2012, 2013  Renesas Solutions Corp.
6 * Copyright (C) 2014 Glider bvba
7 *
8 * Based on spi-sh.c:
9 * Copyright (C) 2011 Renesas Solutions Corp.
10 */
11
12#include <linux/module.h>
13#include <linux/kernel.h>
14#include <linux/sched.h>
15#include <linux/errno.h>
16#include <linux/interrupt.h>
17#include <linux/platform_device.h>
18#include <linux/io.h>
19#include <linux/clk.h>
20#include <linux/dmaengine.h>
21#include <linux/dma-mapping.h>
22#include <linux/of_device.h>
23#include <linux/pm_runtime.h>
24#include <linux/sh_dma.h>
25#include <linux/spi/spi.h>
26#include <linux/spi/rspi.h>
27#include <linux/spinlock.h>
28
29#define RSPI_SPCR		0x00	/* Control Register */
30#define RSPI_SSLP		0x01	/* Slave Select Polarity Register */
31#define RSPI_SPPCR		0x02	/* Pin Control Register */
32#define RSPI_SPSR		0x03	/* Status Register */
33#define RSPI_SPDR		0x04	/* Data Register */
34#define RSPI_SPSCR		0x08	/* Sequence Control Register */
35#define RSPI_SPSSR		0x09	/* Sequence Status Register */
36#define RSPI_SPBR		0x0a	/* Bit Rate Register */
37#define RSPI_SPDCR		0x0b	/* Data Control Register */
38#define RSPI_SPCKD		0x0c	/* Clock Delay Register */
39#define RSPI_SSLND		0x0d	/* Slave Select Negation Delay Register */
40#define RSPI_SPND		0x0e	/* Next-Access Delay Register */
41#define RSPI_SPCR2		0x0f	/* Control Register 2 (SH only) */
42#define RSPI_SPCMD0		0x10	/* Command Register 0 */
43#define RSPI_SPCMD1		0x12	/* Command Register 1 */
44#define RSPI_SPCMD2		0x14	/* Command Register 2 */
45#define RSPI_SPCMD3		0x16	/* Command Register 3 */
46#define RSPI_SPCMD4		0x18	/* Command Register 4 */
47#define RSPI_SPCMD5		0x1a	/* Command Register 5 */
48#define RSPI_SPCMD6		0x1c	/* Command Register 6 */
49#define RSPI_SPCMD7		0x1e	/* Command Register 7 */
50#define RSPI_SPCMD(i)		(RSPI_SPCMD0 + (i) * 2)
51#define RSPI_NUM_SPCMD		8
52#define RSPI_RZ_NUM_SPCMD	4
53#define QSPI_NUM_SPCMD		4
54
55/* RSPI on RZ only */
56#define RSPI_SPBFCR		0x20	/* Buffer Control Register */
57#define RSPI_SPBFDR		0x22	/* Buffer Data Count Setting Register */
58
59/* QSPI only */
60#define QSPI_SPBFCR		0x18	/* Buffer Control Register */
61#define QSPI_SPBDCR		0x1a	/* Buffer Data Count Register */
62#define QSPI_SPBMUL0		0x1c	/* Transfer Data Length Multiplier Setting Register 0 */
63#define QSPI_SPBMUL1		0x20	/* Transfer Data Length Multiplier Setting Register 1 */
64#define QSPI_SPBMUL2		0x24	/* Transfer Data Length Multiplier Setting Register 2 */
65#define QSPI_SPBMUL3		0x28	/* Transfer Data Length Multiplier Setting Register 3 */
66#define QSPI_SPBMUL(i)		(QSPI_SPBMUL0 + (i) * 4)
67
68/* SPCR - Control Register */
69#define SPCR_SPRIE		0x80	/* Receive Interrupt Enable */
70#define SPCR_SPE		0x40	/* Function Enable */
71#define SPCR_SPTIE		0x20	/* Transmit Interrupt Enable */
72#define SPCR_SPEIE		0x10	/* Error Interrupt Enable */
73#define SPCR_MSTR		0x08	/* Master/Slave Mode Select */
74#define SPCR_MODFEN		0x04	/* Mode Fault Error Detection Enable */
75/* RSPI on SH only */
76#define SPCR_TXMD		0x02	/* TX Only Mode (vs. Full Duplex) */
77#define SPCR_SPMS		0x01	/* 3-wire Mode (vs. 4-wire) */
78/* QSPI on R-Car Gen2 only */
79#define SPCR_WSWAP		0x02	/* Word Swap of read-data for DMAC */
80#define SPCR_BSWAP		0x01	/* Byte Swap of read-data for DMAC */
81
82/* SSLP - Slave Select Polarity Register */
83#define SSLP_SSLP(i)		BIT(i)	/* SSLi Signal Polarity Setting */
84
85/* SPPCR - Pin Control Register */
86#define SPPCR_MOIFE		0x20	/* MOSI Idle Value Fixing Enable */
87#define SPPCR_MOIFV		0x10	/* MOSI Idle Fixed Value */
88#define SPPCR_SPOM		0x04
89#define SPPCR_SPLP2		0x02	/* Loopback Mode 2 (non-inverting) */
90#define SPPCR_SPLP		0x01	/* Loopback Mode (inverting) */
91
92#define SPPCR_IO3FV		0x04	/* Single-/Dual-SPI Mode IO3 Output Fixed Value */
93#define SPPCR_IO2FV		0x04	/* Single-/Dual-SPI Mode IO2 Output Fixed Value */
94
95/* SPSR - Status Register */
96#define SPSR_SPRF		0x80	/* Receive Buffer Full Flag */
97#define SPSR_TEND		0x40	/* Transmit End */
98#define SPSR_SPTEF		0x20	/* Transmit Buffer Empty Flag */
99#define SPSR_PERF		0x08	/* Parity Error Flag */
100#define SPSR_MODF		0x04	/* Mode Fault Error Flag */
101#define SPSR_IDLNF		0x02	/* RSPI Idle Flag */
102#define SPSR_OVRF		0x01	/* Overrun Error Flag (RSPI only) */
103
104/* SPSCR - Sequence Control Register */
105#define SPSCR_SPSLN_MASK	0x07	/* Sequence Length Specification */
106
107/* SPSSR - Sequence Status Register */
108#define SPSSR_SPECM_MASK	0x70	/* Command Error Mask */
109#define SPSSR_SPCP_MASK		0x07	/* Command Pointer Mask */
110
111/* SPDCR - Data Control Register */
112#define SPDCR_TXDMY		0x80	/* Dummy Data Transmission Enable */
113#define SPDCR_SPLW1		0x40	/* Access Width Specification (RZ) */
114#define SPDCR_SPLW0		0x20	/* Access Width Specification (RZ) */
115#define SPDCR_SPLLWORD		(SPDCR_SPLW1 | SPDCR_SPLW0)
116#define SPDCR_SPLWORD		SPDCR_SPLW1
117#define SPDCR_SPLBYTE		SPDCR_SPLW0
118#define SPDCR_SPLW		0x20	/* Access Width Specification (SH) */
119#define SPDCR_SPRDTD		0x10	/* Receive Transmit Data Select (SH) */
120#define SPDCR_SLSEL1		0x08
121#define SPDCR_SLSEL0		0x04
122#define SPDCR_SLSEL_MASK	0x0c	/* SSL1 Output Select (SH) */
123#define SPDCR_SPFC1		0x02
124#define SPDCR_SPFC0		0x01
125#define SPDCR_SPFC_MASK		0x03	/* Frame Count Setting (1-4) (SH) */
126
127/* SPCKD - Clock Delay Register */
128#define SPCKD_SCKDL_MASK	0x07	/* Clock Delay Setting (1-8) */
129
130/* SSLND - Slave Select Negation Delay Register */
131#define SSLND_SLNDL_MASK	0x07	/* SSL Negation Delay Setting (1-8) */
132
133/* SPND - Next-Access Delay Register */
134#define SPND_SPNDL_MASK		0x07	/* Next-Access Delay Setting (1-8) */
135
136/* SPCR2 - Control Register 2 */
137#define SPCR2_PTE		0x08	/* Parity Self-Test Enable */
138#define SPCR2_SPIE		0x04	/* Idle Interrupt Enable */
139#define SPCR2_SPOE		0x02	/* Odd Parity Enable (vs. Even) */
140#define SPCR2_SPPE		0x01	/* Parity Enable */
141
142/* SPCMDn - Command Registers */
143#define SPCMD_SCKDEN		0x8000	/* Clock Delay Setting Enable */
144#define SPCMD_SLNDEN		0x4000	/* SSL Negation Delay Setting Enable */
145#define SPCMD_SPNDEN		0x2000	/* Next-Access Delay Enable */
146#define SPCMD_LSBF		0x1000	/* LSB First */
147#define SPCMD_SPB_MASK		0x0f00	/* Data Length Setting */
148#define SPCMD_SPB_8_TO_16(bit)	(((bit - 1) << 8) & SPCMD_SPB_MASK)
149#define SPCMD_SPB_8BIT		0x0000	/* QSPI only */
150#define SPCMD_SPB_16BIT		0x0100
151#define SPCMD_SPB_20BIT		0x0000
152#define SPCMD_SPB_24BIT		0x0100
153#define SPCMD_SPB_32BIT		0x0200
154#define SPCMD_SSLKP		0x0080	/* SSL Signal Level Keeping */
155#define SPCMD_SPIMOD_MASK	0x0060	/* SPI Operating Mode (QSPI only) */
156#define SPCMD_SPIMOD1		0x0040
157#define SPCMD_SPIMOD0		0x0020
158#define SPCMD_SPIMOD_SINGLE	0
159#define SPCMD_SPIMOD_DUAL	SPCMD_SPIMOD0
160#define SPCMD_SPIMOD_QUAD	SPCMD_SPIMOD1
161#define SPCMD_SPRW		0x0010	/* SPI Read/Write Access (Dual/Quad) */
162#define SPCMD_SSLA(i)		((i) << 4)	/* SSL Assert Signal Setting */
163#define SPCMD_BRDV_MASK		0x000c	/* Bit Rate Division Setting */
164#define SPCMD_BRDV(brdv)	((brdv) << 2)
165#define SPCMD_CPOL		0x0002	/* Clock Polarity Setting */
166#define SPCMD_CPHA		0x0001	/* Clock Phase Setting */
167
168/* SPBFCR - Buffer Control Register */
169#define SPBFCR_TXRST		0x80	/* Transmit Buffer Data Reset */
170#define SPBFCR_RXRST		0x40	/* Receive Buffer Data Reset */
171#define SPBFCR_TXTRG_MASK	0x30	/* Transmit Buffer Data Triggering Number */
172#define SPBFCR_RXTRG_MASK	0x07	/* Receive Buffer Data Triggering Number */
173/* QSPI on R-Car Gen2 */
174#define SPBFCR_TXTRG_1B		0x00	/* 31 bytes (1 byte available) */
175#define SPBFCR_TXTRG_32B	0x30	/* 0 byte (32 bytes available) */
176#define SPBFCR_RXTRG_1B		0x00	/* 1 byte (31 bytes available) */
177#define SPBFCR_RXTRG_32B	0x07	/* 32 bytes (0 byte available) */
178
179#define QSPI_BUFFER_SIZE        32u
180
181struct rspi_data {
182	void __iomem *addr;
183	u32 speed_hz;
184	struct spi_controller *ctlr;
185	struct platform_device *pdev;
186	wait_queue_head_t wait;
187	spinlock_t lock;		/* Protects RMW-access to RSPI_SSLP */
188	struct clk *clk;
189	u16 spcmd;
190	u8 spsr;
191	u8 sppcr;
192	int rx_irq, tx_irq;
193	const struct spi_ops *ops;
194
195	unsigned dma_callbacked:1;
196	unsigned byte_access:1;
197};
198
199static void rspi_write8(const struct rspi_data *rspi, u8 data, u16 offset)
200{
201	iowrite8(data, rspi->addr + offset);
202}
203
204static void rspi_write16(const struct rspi_data *rspi, u16 data, u16 offset)
205{
206	iowrite16(data, rspi->addr + offset);
207}
208
209static void rspi_write32(const struct rspi_data *rspi, u32 data, u16 offset)
210{
211	iowrite32(data, rspi->addr + offset);
212}
213
214static u8 rspi_read8(const struct rspi_data *rspi, u16 offset)
215{
216	return ioread8(rspi->addr + offset);
217}
218
219static u16 rspi_read16(const struct rspi_data *rspi, u16 offset)
220{
221	return ioread16(rspi->addr + offset);
222}
223
224static void rspi_write_data(const struct rspi_data *rspi, u16 data)
225{
226	if (rspi->byte_access)
227		rspi_write8(rspi, data, RSPI_SPDR);
228	else /* 16 bit */
229		rspi_write16(rspi, data, RSPI_SPDR);
230}
231
232static u16 rspi_read_data(const struct rspi_data *rspi)
233{
234	if (rspi->byte_access)
235		return rspi_read8(rspi, RSPI_SPDR);
236	else /* 16 bit */
237		return rspi_read16(rspi, RSPI_SPDR);
238}
239
240/* optional functions */
241struct spi_ops {
242	int (*set_config_register)(struct rspi_data *rspi, int access_size);
243	int (*transfer_one)(struct spi_controller *ctlr,
244			    struct spi_device *spi, struct spi_transfer *xfer);
245	u16 extra_mode_bits;
246	u16 min_div;
247	u16 max_div;
248	u16 flags;
249	u16 fifo_size;
250	u8 num_hw_ss;
251};
252
253static void rspi_set_rate(struct rspi_data *rspi)
254{
255	unsigned long clksrc;
256	int brdv = 0, spbr;
257
258	clksrc = clk_get_rate(rspi->clk);
259	spbr = DIV_ROUND_UP(clksrc, 2 * rspi->speed_hz) - 1;
260	while (spbr > 255 && brdv < 3) {
261		brdv++;
262		spbr = DIV_ROUND_UP(spbr + 1, 2) - 1;
263	}
264
265	rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
266	rspi->spcmd |= SPCMD_BRDV(brdv);
267	rspi->speed_hz = DIV_ROUND_UP(clksrc, (2U << brdv) * (spbr + 1));
268}
269
270/*
271 * functions for RSPI on legacy SH
272 */
273static int rspi_set_config_register(struct rspi_data *rspi, int access_size)
274{
275	/* Sets output mode, MOSI signal, and (optionally) loopback */
276	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
277
278	/* Sets transfer bit rate */
279	rspi_set_rate(rspi);
280
281	/* Disable dummy transmission, set 16-bit word access, 1 frame */
282	rspi_write8(rspi, 0, RSPI_SPDCR);
283	rspi->byte_access = 0;
284
285	/* Sets RSPCK, SSL, next-access delay value */
286	rspi_write8(rspi, 0x00, RSPI_SPCKD);
287	rspi_write8(rspi, 0x00, RSPI_SSLND);
288	rspi_write8(rspi, 0x00, RSPI_SPND);
289
290	/* Sets parity, interrupt mask */
291	rspi_write8(rspi, 0x00, RSPI_SPCR2);
292
293	/* Resets sequencer */
294	rspi_write8(rspi, 0, RSPI_SPSCR);
295	rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size);
296	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
297
298	/* Sets RSPI mode */
299	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
300
301	return 0;
302}
303
304/*
305 * functions for RSPI on RZ
306 */
307static int rspi_rz_set_config_register(struct rspi_data *rspi, int access_size)
308{
309	/* Sets output mode, MOSI signal, and (optionally) loopback */
310	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
311
312	/* Sets transfer bit rate */
313	rspi_set_rate(rspi);
314
315	/* Disable dummy transmission, set byte access */
316	rspi_write8(rspi, SPDCR_SPLBYTE, RSPI_SPDCR);
317	rspi->byte_access = 1;
318
319	/* Sets RSPCK, SSL, next-access delay value */
320	rspi_write8(rspi, 0x00, RSPI_SPCKD);
321	rspi_write8(rspi, 0x00, RSPI_SSLND);
322	rspi_write8(rspi, 0x00, RSPI_SPND);
323
324	/* Resets sequencer */
325	rspi_write8(rspi, 0, RSPI_SPSCR);
326	rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size);
327	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
328
329	/* Sets RSPI mode */
330	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
331
332	return 0;
333}
334
335/*
336 * functions for QSPI
337 */
338static int qspi_set_config_register(struct rspi_data *rspi, int access_size)
339{
340	unsigned long clksrc;
341	int brdv = 0, spbr;
342
343	/* Sets output mode, MOSI signal, and (optionally) loopback */
344	rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
345
346	/* Sets transfer bit rate */
347	clksrc = clk_get_rate(rspi->clk);
348	if (rspi->speed_hz >= clksrc) {
349		spbr = 0;
350		rspi->speed_hz = clksrc;
351	} else {
352		spbr = DIV_ROUND_UP(clksrc, 2 * rspi->speed_hz);
353		while (spbr > 255 && brdv < 3) {
354			brdv++;
355			spbr = DIV_ROUND_UP(spbr, 2);
356		}
357		spbr = clamp(spbr, 0, 255);
358		rspi->speed_hz = DIV_ROUND_UP(clksrc, (2U << brdv) * spbr);
359	}
360	rspi_write8(rspi, spbr, RSPI_SPBR);
361	rspi->spcmd |= SPCMD_BRDV(brdv);
362
363	/* Disable dummy transmission, set byte access */
364	rspi_write8(rspi, 0, RSPI_SPDCR);
365	rspi->byte_access = 1;
366
367	/* Sets RSPCK, SSL, next-access delay value */
368	rspi_write8(rspi, 0x00, RSPI_SPCKD);
369	rspi_write8(rspi, 0x00, RSPI_SSLND);
370	rspi_write8(rspi, 0x00, RSPI_SPND);
371
372	/* Data Length Setting */
373	if (access_size == 8)
374		rspi->spcmd |= SPCMD_SPB_8BIT;
375	else if (access_size == 16)
376		rspi->spcmd |= SPCMD_SPB_16BIT;
377	else
378		rspi->spcmd |= SPCMD_SPB_32BIT;
379
380	rspi->spcmd |= SPCMD_SCKDEN | SPCMD_SLNDEN | SPCMD_SPNDEN;
381
382	/* Resets transfer data length */
383	rspi_write32(rspi, 0, QSPI_SPBMUL0);
384
385	/* Resets transmit and receive buffer */
386	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
387	/* Sets buffer to allow normal operation */
388	rspi_write8(rspi, 0x00, QSPI_SPBFCR);
389
390	/* Resets sequencer */
391	rspi_write8(rspi, 0, RSPI_SPSCR);
392	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
393
394	/* Sets RSPI mode */
395	rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
396
397	return 0;
398}
399
400static void qspi_update(const struct rspi_data *rspi, u8 mask, u8 val, u8 reg)
401{
402	u8 data;
403
404	data = rspi_read8(rspi, reg);
405	data &= ~mask;
406	data |= (val & mask);
407	rspi_write8(rspi, data, reg);
408}
409
410static unsigned int qspi_set_send_trigger(struct rspi_data *rspi,
411					  unsigned int len)
412{
413	unsigned int n;
414
415	n = min(len, QSPI_BUFFER_SIZE);
416
417	if (len >= QSPI_BUFFER_SIZE) {
418		/* sets triggering number to 32 bytes */
419		qspi_update(rspi, SPBFCR_TXTRG_MASK,
420			     SPBFCR_TXTRG_32B, QSPI_SPBFCR);
421	} else {
422		/* sets triggering number to 1 byte */
423		qspi_update(rspi, SPBFCR_TXTRG_MASK,
424			     SPBFCR_TXTRG_1B, QSPI_SPBFCR);
425	}
426
427	return n;
428}
429
430static int qspi_set_receive_trigger(struct rspi_data *rspi, unsigned int len)
431{
432	unsigned int n;
433
434	n = min(len, QSPI_BUFFER_SIZE);
435
436	if (len >= QSPI_BUFFER_SIZE) {
437		/* sets triggering number to 32 bytes */
438		qspi_update(rspi, SPBFCR_RXTRG_MASK,
439			     SPBFCR_RXTRG_32B, QSPI_SPBFCR);
440	} else {
441		/* sets triggering number to 1 byte */
442		qspi_update(rspi, SPBFCR_RXTRG_MASK,
443			     SPBFCR_RXTRG_1B, QSPI_SPBFCR);
444	}
445	return n;
446}
447
448static void rspi_enable_irq(const struct rspi_data *rspi, u8 enable)
449{
450	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | enable, RSPI_SPCR);
451}
452
453static void rspi_disable_irq(const struct rspi_data *rspi, u8 disable)
454{
455	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~disable, RSPI_SPCR);
456}
457
458static int rspi_wait_for_interrupt(struct rspi_data *rspi, u8 wait_mask,
459				   u8 enable_bit)
460{
461	int ret;
462
463	rspi->spsr = rspi_read8(rspi, RSPI_SPSR);
464	if (rspi->spsr & wait_mask)
465		return 0;
466
467	rspi_enable_irq(rspi, enable_bit);
468	ret = wait_event_timeout(rspi->wait, rspi->spsr & wait_mask, HZ);
469	if (ret == 0 && !(rspi->spsr & wait_mask))
470		return -ETIMEDOUT;
471
472	return 0;
473}
474
475static inline int rspi_wait_for_tx_empty(struct rspi_data *rspi)
476{
477	return rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
478}
479
480static inline int rspi_wait_for_rx_full(struct rspi_data *rspi)
481{
482	return rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE);
483}
484
485static int rspi_data_out(struct rspi_data *rspi, u8 data)
486{
487	int error = rspi_wait_for_tx_empty(rspi);
488	if (error < 0) {
489		dev_err(&rspi->ctlr->dev, "transmit timeout\n");
490		return error;
491	}
492	rspi_write_data(rspi, data);
493	return 0;
494}
495
496static int rspi_data_in(struct rspi_data *rspi)
497{
498	int error;
499	u8 data;
500
501	error = rspi_wait_for_rx_full(rspi);
502	if (error < 0) {
503		dev_err(&rspi->ctlr->dev, "receive timeout\n");
504		return error;
505	}
506	data = rspi_read_data(rspi);
507	return data;
508}
509
510static int rspi_pio_transfer(struct rspi_data *rspi, const u8 *tx, u8 *rx,
511			     unsigned int n)
512{
513	while (n-- > 0) {
514		if (tx) {
515			int ret = rspi_data_out(rspi, *tx++);
516			if (ret < 0)
517				return ret;
518		}
519		if (rx) {
520			int ret = rspi_data_in(rspi);
521			if (ret < 0)
522				return ret;
523			*rx++ = ret;
524		}
525	}
526
527	return 0;
528}
529
530static void rspi_dma_complete(void *arg)
531{
532	struct rspi_data *rspi = arg;
533
534	rspi->dma_callbacked = 1;
535	wake_up_interruptible(&rspi->wait);
536}
537
538static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
539			     struct sg_table *rx)
540{
541	struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL;
542	u8 irq_mask = 0;
543	unsigned int other_irq = 0;
544	dma_cookie_t cookie;
545	int ret;
546
547	/* First prepare and submit the DMA request(s), as this may fail */
548	if (rx) {
549		desc_rx = dmaengine_prep_slave_sg(rspi->ctlr->dma_rx, rx->sgl,
550					rx->nents, DMA_DEV_TO_MEM,
551					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
552		if (!desc_rx) {
553			ret = -EAGAIN;
554			goto no_dma_rx;
555		}
556
557		desc_rx->callback = rspi_dma_complete;
558		desc_rx->callback_param = rspi;
559		cookie = dmaengine_submit(desc_rx);
560		if (dma_submit_error(cookie)) {
561			ret = cookie;
562			goto no_dma_rx;
563		}
564
565		irq_mask |= SPCR_SPRIE;
566	}
567
568	if (tx) {
569		desc_tx = dmaengine_prep_slave_sg(rspi->ctlr->dma_tx, tx->sgl,
570					tx->nents, DMA_MEM_TO_DEV,
571					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
572		if (!desc_tx) {
573			ret = -EAGAIN;
574			goto no_dma_tx;
575		}
576
577		if (rx) {
578			/* No callback */
579			desc_tx->callback = NULL;
580		} else {
581			desc_tx->callback = rspi_dma_complete;
582			desc_tx->callback_param = rspi;
583		}
584		cookie = dmaengine_submit(desc_tx);
585		if (dma_submit_error(cookie)) {
586			ret = cookie;
587			goto no_dma_tx;
588		}
589
590		irq_mask |= SPCR_SPTIE;
591	}
592
593	/*
594	 * DMAC needs SPxIE, but if SPxIE is set, the IRQ routine will be
595	 * called. So, this driver disables the IRQ while DMA transfer.
596	 */
597	if (tx)
598		disable_irq(other_irq = rspi->tx_irq);
599	if (rx && rspi->rx_irq != other_irq)
600		disable_irq(rspi->rx_irq);
601
602	rspi_enable_irq(rspi, irq_mask);
603	rspi->dma_callbacked = 0;
604
605	/* Now start DMA */
606	if (rx)
607		dma_async_issue_pending(rspi->ctlr->dma_rx);
608	if (tx)
609		dma_async_issue_pending(rspi->ctlr->dma_tx);
610
611	ret = wait_event_interruptible_timeout(rspi->wait,
612					       rspi->dma_callbacked, HZ);
613	if (ret > 0 && rspi->dma_callbacked) {
614		ret = 0;
615		if (tx)
616			dmaengine_synchronize(rspi->ctlr->dma_tx);
617		if (rx)
618			dmaengine_synchronize(rspi->ctlr->dma_rx);
619	} else {
620		if (!ret) {
621			dev_err(&rspi->ctlr->dev, "DMA timeout\n");
622			ret = -ETIMEDOUT;
623		}
624		if (tx)
625			dmaengine_terminate_all(rspi->ctlr->dma_tx);
626		if (rx)
627			dmaengine_terminate_all(rspi->ctlr->dma_rx);
628	}
629
630	rspi_disable_irq(rspi, irq_mask);
631
632	if (tx)
633		enable_irq(rspi->tx_irq);
634	if (rx && rspi->rx_irq != other_irq)
635		enable_irq(rspi->rx_irq);
636
637	return ret;
638
639no_dma_tx:
640	if (rx)
641		dmaengine_terminate_all(rspi->ctlr->dma_rx);
642no_dma_rx:
643	if (ret == -EAGAIN) {
644		dev_warn_once(&rspi->ctlr->dev,
645			      "DMA not available, falling back to PIO\n");
646	}
647	return ret;
648}
649
650static void rspi_receive_init(const struct rspi_data *rspi)
651{
652	u8 spsr;
653
654	spsr = rspi_read8(rspi, RSPI_SPSR);
655	if (spsr & SPSR_SPRF)
656		rspi_read_data(rspi);	/* dummy read */
657	if (spsr & SPSR_OVRF)
658		rspi_write8(rspi, rspi_read8(rspi, RSPI_SPSR) & ~SPSR_OVRF,
659			    RSPI_SPSR);
660}
661
662static void rspi_rz_receive_init(const struct rspi_data *rspi)
663{
664	rspi_receive_init(rspi);
665	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, RSPI_SPBFCR);
666	rspi_write8(rspi, 0, RSPI_SPBFCR);
667}
668
669static void qspi_receive_init(const struct rspi_data *rspi)
670{
671	u8 spsr;
672
673	spsr = rspi_read8(rspi, RSPI_SPSR);
674	if (spsr & SPSR_SPRF)
675		rspi_read_data(rspi);   /* dummy read */
676	rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
677	rspi_write8(rspi, 0, QSPI_SPBFCR);
678}
679
680static bool __rspi_can_dma(const struct rspi_data *rspi,
681			   const struct spi_transfer *xfer)
682{
683	return xfer->len > rspi->ops->fifo_size;
684}
685
686static bool rspi_can_dma(struct spi_controller *ctlr, struct spi_device *spi,
687			 struct spi_transfer *xfer)
688{
689	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
690
691	return __rspi_can_dma(rspi, xfer);
692}
693
694static int rspi_dma_check_then_transfer(struct rspi_data *rspi,
695					 struct spi_transfer *xfer)
696{
697	if (!rspi->ctlr->can_dma || !__rspi_can_dma(rspi, xfer))
698		return -EAGAIN;
699
700	/* rx_buf can be NULL on RSPI on SH in TX-only Mode */
701	return rspi_dma_transfer(rspi, &xfer->tx_sg,
702				xfer->rx_buf ? &xfer->rx_sg : NULL);
703}
704
705static int rspi_common_transfer(struct rspi_data *rspi,
706				struct spi_transfer *xfer)
707{
708	int ret;
709
710	xfer->effective_speed_hz = rspi->speed_hz;
711
712	ret = rspi_dma_check_then_transfer(rspi, xfer);
713	if (ret != -EAGAIN)
714		return ret;
715
716	ret = rspi_pio_transfer(rspi, xfer->tx_buf, xfer->rx_buf, xfer->len);
717	if (ret < 0)
718		return ret;
719
720	/* Wait for the last transmission */
721	rspi_wait_for_tx_empty(rspi);
722
723	return 0;
724}
725
726static int rspi_transfer_one(struct spi_controller *ctlr,
727			     struct spi_device *spi, struct spi_transfer *xfer)
728{
729	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
730	u8 spcr;
731
732	spcr = rspi_read8(rspi, RSPI_SPCR);
733	if (xfer->rx_buf) {
734		rspi_receive_init(rspi);
735		spcr &= ~SPCR_TXMD;
736	} else {
737		spcr |= SPCR_TXMD;
738	}
739	rspi_write8(rspi, spcr, RSPI_SPCR);
740
741	return rspi_common_transfer(rspi, xfer);
742}
743
744static int rspi_rz_transfer_one(struct spi_controller *ctlr,
745				struct spi_device *spi,
746				struct spi_transfer *xfer)
747{
748	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
749
750	rspi_rz_receive_init(rspi);
751
752	return rspi_common_transfer(rspi, xfer);
753}
754
755static int qspi_trigger_transfer_out_in(struct rspi_data *rspi, const u8 *tx,
756					u8 *rx, unsigned int len)
757{
758	unsigned int i, n;
759	int ret;
760
761	while (len > 0) {
762		n = qspi_set_send_trigger(rspi, len);
763		qspi_set_receive_trigger(rspi, len);
764		ret = rspi_wait_for_tx_empty(rspi);
765		if (ret < 0) {
766			dev_err(&rspi->ctlr->dev, "transmit timeout\n");
767			return ret;
768		}
769		for (i = 0; i < n; i++)
770			rspi_write_data(rspi, *tx++);
771
772		ret = rspi_wait_for_rx_full(rspi);
773		if (ret < 0) {
774			dev_err(&rspi->ctlr->dev, "receive timeout\n");
775			return ret;
776		}
777		for (i = 0; i < n; i++)
778			*rx++ = rspi_read_data(rspi);
779
780		len -= n;
781	}
782
783	return 0;
784}
785
786static int qspi_transfer_out_in(struct rspi_data *rspi,
787				struct spi_transfer *xfer)
788{
789	int ret;
790
791	qspi_receive_init(rspi);
792
793	ret = rspi_dma_check_then_transfer(rspi, xfer);
794	if (ret != -EAGAIN)
795		return ret;
796
797	return qspi_trigger_transfer_out_in(rspi, xfer->tx_buf,
798					    xfer->rx_buf, xfer->len);
799}
800
801static int qspi_transfer_out(struct rspi_data *rspi, struct spi_transfer *xfer)
802{
803	const u8 *tx = xfer->tx_buf;
804	unsigned int n = xfer->len;
805	unsigned int i, len;
806	int ret;
807
808	if (rspi->ctlr->can_dma && __rspi_can_dma(rspi, xfer)) {
809		ret = rspi_dma_transfer(rspi, &xfer->tx_sg, NULL);
810		if (ret != -EAGAIN)
811			return ret;
812	}
813
814	while (n > 0) {
815		len = qspi_set_send_trigger(rspi, n);
816		ret = rspi_wait_for_tx_empty(rspi);
817		if (ret < 0) {
818			dev_err(&rspi->ctlr->dev, "transmit timeout\n");
819			return ret;
820		}
821		for (i = 0; i < len; i++)
822			rspi_write_data(rspi, *tx++);
823
824		n -= len;
825	}
826
827	/* Wait for the last transmission */
828	rspi_wait_for_tx_empty(rspi);
829
830	return 0;
831}
832
833static int qspi_transfer_in(struct rspi_data *rspi, struct spi_transfer *xfer)
834{
835	u8 *rx = xfer->rx_buf;
836	unsigned int n = xfer->len;
837	unsigned int i, len;
838	int ret;
839
840	if (rspi->ctlr->can_dma && __rspi_can_dma(rspi, xfer)) {
841		int ret = rspi_dma_transfer(rspi, NULL, &xfer->rx_sg);
842		if (ret != -EAGAIN)
843			return ret;
844	}
845
846	while (n > 0) {
847		len = qspi_set_receive_trigger(rspi, n);
848		ret = rspi_wait_for_rx_full(rspi);
849		if (ret < 0) {
850			dev_err(&rspi->ctlr->dev, "receive timeout\n");
851			return ret;
852		}
853		for (i = 0; i < len; i++)
854			*rx++ = rspi_read_data(rspi);
855
856		n -= len;
857	}
858
859	return 0;
860}
861
862static int qspi_transfer_one(struct spi_controller *ctlr,
863			     struct spi_device *spi, struct spi_transfer *xfer)
864{
865	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
866
867	xfer->effective_speed_hz = rspi->speed_hz;
868	if (spi->mode & SPI_LOOP) {
869		return qspi_transfer_out_in(rspi, xfer);
870	} else if (xfer->tx_nbits > SPI_NBITS_SINGLE) {
871		/* Quad or Dual SPI Write */
872		return qspi_transfer_out(rspi, xfer);
873	} else if (xfer->rx_nbits > SPI_NBITS_SINGLE) {
874		/* Quad or Dual SPI Read */
875		return qspi_transfer_in(rspi, xfer);
876	} else {
877		/* Single SPI Transfer */
878		return qspi_transfer_out_in(rspi, xfer);
879	}
880}
881
882static u16 qspi_transfer_mode(const struct spi_transfer *xfer)
883{
884	if (xfer->tx_buf)
885		switch (xfer->tx_nbits) {
886		case SPI_NBITS_QUAD:
887			return SPCMD_SPIMOD_QUAD;
888		case SPI_NBITS_DUAL:
889			return SPCMD_SPIMOD_DUAL;
890		default:
891			return 0;
892		}
893	if (xfer->rx_buf)
894		switch (xfer->rx_nbits) {
895		case SPI_NBITS_QUAD:
896			return SPCMD_SPIMOD_QUAD | SPCMD_SPRW;
897		case SPI_NBITS_DUAL:
898			return SPCMD_SPIMOD_DUAL | SPCMD_SPRW;
899		default:
900			return 0;
901		}
902
903	return 0;
904}
905
906static int qspi_setup_sequencer(struct rspi_data *rspi,
907				const struct spi_message *msg)
908{
909	const struct spi_transfer *xfer;
910	unsigned int i = 0, len = 0;
911	u16 current_mode = 0xffff, mode;
912
913	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
914		mode = qspi_transfer_mode(xfer);
915		if (mode == current_mode) {
916			len += xfer->len;
917			continue;
918		}
919
920		/* Transfer mode change */
921		if (i) {
922			/* Set transfer data length of previous transfer */
923			rspi_write32(rspi, len, QSPI_SPBMUL(i - 1));
924		}
925
926		if (i >= QSPI_NUM_SPCMD) {
927			dev_err(&msg->spi->dev,
928				"Too many different transfer modes");
929			return -EINVAL;
930		}
931
932		/* Program transfer mode for this transfer */
933		rspi_write16(rspi, rspi->spcmd | mode, RSPI_SPCMD(i));
934		current_mode = mode;
935		len = xfer->len;
936		i++;
937	}
938	if (i) {
939		/* Set final transfer data length and sequence length */
940		rspi_write32(rspi, len, QSPI_SPBMUL(i - 1));
941		rspi_write8(rspi, i - 1, RSPI_SPSCR);
942	}
943
944	return 0;
945}
946
947static int rspi_setup(struct spi_device *spi)
948{
949	struct rspi_data *rspi = spi_controller_get_devdata(spi->controller);
950	u8 sslp;
951
952	if (spi->cs_gpiod)
953		return 0;
954
955	pm_runtime_get_sync(&rspi->pdev->dev);
956	spin_lock_irq(&rspi->lock);
957
958	sslp = rspi_read8(rspi, RSPI_SSLP);
959	if (spi->mode & SPI_CS_HIGH)
960		sslp |= SSLP_SSLP(spi->chip_select);
961	else
962		sslp &= ~SSLP_SSLP(spi->chip_select);
963	rspi_write8(rspi, sslp, RSPI_SSLP);
964
965	spin_unlock_irq(&rspi->lock);
966	pm_runtime_put(&rspi->pdev->dev);
967	return 0;
968}
969
970static int rspi_prepare_message(struct spi_controller *ctlr,
971				struct spi_message *msg)
972{
973	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
974	struct spi_device *spi = msg->spi;
975	const struct spi_transfer *xfer;
976	int ret;
977
978	/*
979	 * As the Bit Rate Register must not be changed while the device is
980	 * active, all transfers in a message must use the same bit rate.
981	 * In theory, the sequencer could be enabled, and each Command Register
982	 * could divide the base bit rate by a different value.
983	 * However, most RSPI variants do not have Transfer Data Length
984	 * Multiplier Setting Registers, so each sequence step would be limited
985	 * to a single word, making this feature unsuitable for large
986	 * transfers, which would gain most from it.
987	 */
988	rspi->speed_hz = spi->max_speed_hz;
989	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
990		if (xfer->speed_hz < rspi->speed_hz)
991			rspi->speed_hz = xfer->speed_hz;
992	}
993
994	rspi->spcmd = SPCMD_SSLKP;
995	if (spi->mode & SPI_CPOL)
996		rspi->spcmd |= SPCMD_CPOL;
997	if (spi->mode & SPI_CPHA)
998		rspi->spcmd |= SPCMD_CPHA;
999	if (spi->mode & SPI_LSB_FIRST)
1000		rspi->spcmd |= SPCMD_LSBF;
1001
1002	/* Configure slave signal to assert */
1003	rspi->spcmd |= SPCMD_SSLA(spi->cs_gpiod ? rspi->ctlr->unused_native_cs
1004						: spi->chip_select);
1005
1006	/* CMOS output mode and MOSI signal from previous transfer */
1007	rspi->sppcr = 0;
1008	if (spi->mode & SPI_LOOP)
1009		rspi->sppcr |= SPPCR_SPLP;
1010
1011	rspi->ops->set_config_register(rspi, 8);
1012
1013	if (msg->spi->mode &
1014	    (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD)) {
1015		/* Setup sequencer for messages with multiple transfer modes */
1016		ret = qspi_setup_sequencer(rspi, msg);
1017		if (ret < 0)
1018			return ret;
1019	}
1020
1021	/* Enable SPI function in master mode */
1022	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_SPE, RSPI_SPCR);
1023	return 0;
1024}
1025
1026static int rspi_unprepare_message(struct spi_controller *ctlr,
1027				  struct spi_message *msg)
1028{
1029	struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
1030
1031	/* Disable SPI function */
1032	rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_SPE, RSPI_SPCR);
1033
1034	/* Reset sequencer for Single SPI Transfers */
1035	rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
1036	rspi_write8(rspi, 0, RSPI_SPSCR);
1037	return 0;
1038}
1039
1040static irqreturn_t rspi_irq_mux(int irq, void *_sr)
1041{
1042	struct rspi_data *rspi = _sr;
1043	u8 spsr;
1044	irqreturn_t ret = IRQ_NONE;
1045	u8 disable_irq = 0;
1046
1047	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
1048	if (spsr & SPSR_SPRF)
1049		disable_irq |= SPCR_SPRIE;
1050	if (spsr & SPSR_SPTEF)
1051		disable_irq |= SPCR_SPTIE;
1052
1053	if (disable_irq) {
1054		ret = IRQ_HANDLED;
1055		rspi_disable_irq(rspi, disable_irq);
1056		wake_up(&rspi->wait);
1057	}
1058
1059	return ret;
1060}
1061
1062static irqreturn_t rspi_irq_rx(int irq, void *_sr)
1063{
1064	struct rspi_data *rspi = _sr;
1065	u8 spsr;
1066
1067	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
1068	if (spsr & SPSR_SPRF) {
1069		rspi_disable_irq(rspi, SPCR_SPRIE);
1070		wake_up(&rspi->wait);
1071		return IRQ_HANDLED;
1072	}
1073
1074	return 0;
1075}
1076
1077static irqreturn_t rspi_irq_tx(int irq, void *_sr)
1078{
1079	struct rspi_data *rspi = _sr;
1080	u8 spsr;
1081
1082	rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
1083	if (spsr & SPSR_SPTEF) {
1084		rspi_disable_irq(rspi, SPCR_SPTIE);
1085		wake_up(&rspi->wait);
1086		return IRQ_HANDLED;
1087	}
1088
1089	return 0;
1090}
1091
1092static struct dma_chan *rspi_request_dma_chan(struct device *dev,
1093					      enum dma_transfer_direction dir,
1094					      unsigned int id,
1095					      dma_addr_t port_addr)
1096{
1097	dma_cap_mask_t mask;
1098	struct dma_chan *chan;
1099	struct dma_slave_config cfg;
1100	int ret;
1101
1102	dma_cap_zero(mask);
1103	dma_cap_set(DMA_SLAVE, mask);
1104
1105	chan = dma_request_slave_channel_compat(mask, shdma_chan_filter,
1106				(void *)(unsigned long)id, dev,
1107				dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1108	if (!chan) {
1109		dev_warn(dev, "dma_request_slave_channel_compat failed\n");
1110		return NULL;
1111	}
1112
1113	memset(&cfg, 0, sizeof(cfg));
1114	cfg.dst_addr = port_addr + RSPI_SPDR;
1115	cfg.src_addr = port_addr + RSPI_SPDR;
1116	cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1117	cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1118	cfg.direction = dir;
1119
1120	ret = dmaengine_slave_config(chan, &cfg);
1121	if (ret) {
1122		dev_warn(dev, "dmaengine_slave_config failed %d\n", ret);
1123		dma_release_channel(chan);
1124		return NULL;
1125	}
1126
1127	return chan;
1128}
1129
1130static int rspi_request_dma(struct device *dev, struct spi_controller *ctlr,
1131			    const struct resource *res)
1132{
1133	const struct rspi_plat_data *rspi_pd = dev_get_platdata(dev);
1134	unsigned int dma_tx_id, dma_rx_id;
1135
1136	if (dev->of_node) {
1137		/* In the OF case we will get the slave IDs from the DT */
1138		dma_tx_id = 0;
1139		dma_rx_id = 0;
1140	} else if (rspi_pd && rspi_pd->dma_tx_id && rspi_pd->dma_rx_id) {
1141		dma_tx_id = rspi_pd->dma_tx_id;
1142		dma_rx_id = rspi_pd->dma_rx_id;
1143	} else {
1144		/* The driver assumes no error. */
1145		return 0;
1146	}
1147
1148	ctlr->dma_tx = rspi_request_dma_chan(dev, DMA_MEM_TO_DEV, dma_tx_id,
1149					     res->start);
1150	if (!ctlr->dma_tx)
1151		return -ENODEV;
1152
1153	ctlr->dma_rx = rspi_request_dma_chan(dev, DMA_DEV_TO_MEM, dma_rx_id,
1154					     res->start);
1155	if (!ctlr->dma_rx) {
1156		dma_release_channel(ctlr->dma_tx);
1157		ctlr->dma_tx = NULL;
1158		return -ENODEV;
1159	}
1160
1161	ctlr->can_dma = rspi_can_dma;
1162	dev_info(dev, "DMA available");
1163	return 0;
1164}
1165
1166static void rspi_release_dma(struct spi_controller *ctlr)
1167{
1168	if (ctlr->dma_tx)
1169		dma_release_channel(ctlr->dma_tx);
1170	if (ctlr->dma_rx)
1171		dma_release_channel(ctlr->dma_rx);
1172}
1173
1174static int rspi_remove(struct platform_device *pdev)
1175{
1176	struct rspi_data *rspi = platform_get_drvdata(pdev);
1177
1178	rspi_release_dma(rspi->ctlr);
1179	pm_runtime_disable(&pdev->dev);
1180
1181	return 0;
1182}
1183
1184static const struct spi_ops rspi_ops = {
1185	.set_config_register =	rspi_set_config_register,
1186	.transfer_one =		rspi_transfer_one,
1187	.min_div =		2,
1188	.max_div =		4096,
1189	.flags =		SPI_CONTROLLER_MUST_TX,
1190	.fifo_size =		8,
1191	.num_hw_ss =		2,
1192};
1193
1194static const struct spi_ops rspi_rz_ops = {
1195	.set_config_register =	rspi_rz_set_config_register,
1196	.transfer_one =		rspi_rz_transfer_one,
1197	.min_div =		2,
1198	.max_div =		4096,
1199	.flags =		SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX,
1200	.fifo_size =		8,	/* 8 for TX, 32 for RX */
1201	.num_hw_ss =		1,
1202};
1203
1204static const struct spi_ops qspi_ops = {
1205	.set_config_register =	qspi_set_config_register,
1206	.transfer_one =		qspi_transfer_one,
1207	.extra_mode_bits =	SPI_TX_DUAL | SPI_TX_QUAD |
1208				SPI_RX_DUAL | SPI_RX_QUAD,
1209	.min_div =		1,
1210	.max_div =		4080,
1211	.flags =		SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX,
1212	.fifo_size =		32,
1213	.num_hw_ss =		1,
1214};
1215
1216#ifdef CONFIG_OF
1217static const struct of_device_id rspi_of_match[] = {
1218	/* RSPI on legacy SH */
1219	{ .compatible = "renesas,rspi", .data = &rspi_ops },
1220	/* RSPI on RZ/A1H */
1221	{ .compatible = "renesas,rspi-rz", .data = &rspi_rz_ops },
1222	/* QSPI on R-Car Gen2 */
1223	{ .compatible = "renesas,qspi", .data = &qspi_ops },
1224	{ /* sentinel */ }
1225};
1226
1227MODULE_DEVICE_TABLE(of, rspi_of_match);
1228
1229static int rspi_parse_dt(struct device *dev, struct spi_controller *ctlr)
1230{
1231	u32 num_cs;
1232	int error;
1233
1234	/* Parse DT properties */
1235	error = of_property_read_u32(dev->of_node, "num-cs", &num_cs);
1236	if (error) {
1237		dev_err(dev, "of_property_read_u32 num-cs failed %d\n", error);
1238		return error;
1239	}
1240
1241	ctlr->num_chipselect = num_cs;
1242	return 0;
1243}
1244#else
1245#define rspi_of_match	NULL
1246static inline int rspi_parse_dt(struct device *dev, struct spi_controller *ctlr)
1247{
1248	return -EINVAL;
1249}
1250#endif /* CONFIG_OF */
1251
1252static int rspi_request_irq(struct device *dev, unsigned int irq,
1253			    irq_handler_t handler, const char *suffix,
1254			    void *dev_id)
1255{
1256	const char *name = devm_kasprintf(dev, GFP_KERNEL, "%s:%s",
1257					  dev_name(dev), suffix);
1258	if (!name)
1259		return -ENOMEM;
1260
1261	return devm_request_irq(dev, irq, handler, 0, name, dev_id);
1262}
1263
1264static int rspi_probe(struct platform_device *pdev)
1265{
1266	struct resource *res;
1267	struct spi_controller *ctlr;
1268	struct rspi_data *rspi;
1269	int ret;
1270	const struct rspi_plat_data *rspi_pd;
1271	const struct spi_ops *ops;
1272	unsigned long clksrc;
1273
1274	ctlr = spi_alloc_master(&pdev->dev, sizeof(struct rspi_data));
1275	if (ctlr == NULL)
1276		return -ENOMEM;
1277
1278	ops = of_device_get_match_data(&pdev->dev);
1279	if (ops) {
1280		ret = rspi_parse_dt(&pdev->dev, ctlr);
1281		if (ret)
1282			goto error1;
1283	} else {
1284		ops = (struct spi_ops *)pdev->id_entry->driver_data;
1285		rspi_pd = dev_get_platdata(&pdev->dev);
1286		if (rspi_pd && rspi_pd->num_chipselect)
1287			ctlr->num_chipselect = rspi_pd->num_chipselect;
1288		else
1289			ctlr->num_chipselect = 2; /* default */
1290	}
1291
1292	rspi = spi_controller_get_devdata(ctlr);
1293	platform_set_drvdata(pdev, rspi);
1294	rspi->ops = ops;
1295	rspi->ctlr = ctlr;
1296
1297	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1298	rspi->addr = devm_ioremap_resource(&pdev->dev, res);
1299	if (IS_ERR(rspi->addr)) {
1300		ret = PTR_ERR(rspi->addr);
1301		goto error1;
1302	}
1303
1304	rspi->clk = devm_clk_get(&pdev->dev, NULL);
1305	if (IS_ERR(rspi->clk)) {
1306		dev_err(&pdev->dev, "cannot get clock\n");
1307		ret = PTR_ERR(rspi->clk);
1308		goto error1;
1309	}
1310
1311	rspi->pdev = pdev;
1312	pm_runtime_enable(&pdev->dev);
1313
1314	init_waitqueue_head(&rspi->wait);
1315	spin_lock_init(&rspi->lock);
1316
1317	ctlr->bus_num = pdev->id;
1318	ctlr->setup = rspi_setup;
1319	ctlr->auto_runtime_pm = true;
1320	ctlr->transfer_one = ops->transfer_one;
1321	ctlr->prepare_message = rspi_prepare_message;
1322	ctlr->unprepare_message = rspi_unprepare_message;
1323	ctlr->mode_bits = SPI_CPHA | SPI_CPOL | SPI_CS_HIGH | SPI_LSB_FIRST |
1324			  SPI_LOOP | ops->extra_mode_bits;
1325	clksrc = clk_get_rate(rspi->clk);
1326	ctlr->min_speed_hz = DIV_ROUND_UP(clksrc, ops->max_div);
1327	ctlr->max_speed_hz = DIV_ROUND_UP(clksrc, ops->min_div);
1328	ctlr->flags = ops->flags;
1329	ctlr->dev.of_node = pdev->dev.of_node;
1330	ctlr->use_gpio_descriptors = true;
1331	ctlr->max_native_cs = rspi->ops->num_hw_ss;
1332
1333	ret = platform_get_irq_byname_optional(pdev, "rx");
1334	if (ret < 0) {
1335		ret = platform_get_irq_byname_optional(pdev, "mux");
1336		if (ret < 0)
1337			ret = platform_get_irq(pdev, 0);
1338		if (ret >= 0)
1339			rspi->rx_irq = rspi->tx_irq = ret;
1340	} else {
1341		rspi->rx_irq = ret;
1342		ret = platform_get_irq_byname(pdev, "tx");
1343		if (ret >= 0)
1344			rspi->tx_irq = ret;
1345	}
1346
1347	if (rspi->rx_irq == rspi->tx_irq) {
1348		/* Single multiplexed interrupt */
1349		ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_mux,
1350				       "mux", rspi);
1351	} else {
1352		/* Multi-interrupt mode, only SPRI and SPTI are used */
1353		ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_rx,
1354				       "rx", rspi);
1355		if (!ret)
1356			ret = rspi_request_irq(&pdev->dev, rspi->tx_irq,
1357					       rspi_irq_tx, "tx", rspi);
1358	}
1359	if (ret < 0) {
1360		dev_err(&pdev->dev, "request_irq error\n");
1361		goto error2;
1362	}
1363
1364	ret = rspi_request_dma(&pdev->dev, ctlr, res);
1365	if (ret < 0)
1366		dev_warn(&pdev->dev, "DMA not available, using PIO\n");
1367
1368	ret = devm_spi_register_controller(&pdev->dev, ctlr);
1369	if (ret < 0) {
1370		dev_err(&pdev->dev, "devm_spi_register_controller error.\n");
1371		goto error3;
1372	}
1373
1374	dev_info(&pdev->dev, "probed\n");
1375
1376	return 0;
1377
1378error3:
1379	rspi_release_dma(ctlr);
1380error2:
1381	pm_runtime_disable(&pdev->dev);
1382error1:
1383	spi_controller_put(ctlr);
1384
1385	return ret;
1386}
1387
1388static const struct platform_device_id spi_driver_ids[] = {
1389	{ "rspi",	(kernel_ulong_t)&rspi_ops },
1390	{},
1391};
1392
1393MODULE_DEVICE_TABLE(platform, spi_driver_ids);
1394
1395#ifdef CONFIG_PM_SLEEP
1396static int rspi_suspend(struct device *dev)
1397{
1398	struct rspi_data *rspi = dev_get_drvdata(dev);
1399
1400	return spi_controller_suspend(rspi->ctlr);
1401}
1402
1403static int rspi_resume(struct device *dev)
1404{
1405	struct rspi_data *rspi = dev_get_drvdata(dev);
1406
1407	return spi_controller_resume(rspi->ctlr);
1408}
1409
1410static SIMPLE_DEV_PM_OPS(rspi_pm_ops, rspi_suspend, rspi_resume);
1411#define DEV_PM_OPS	&rspi_pm_ops
1412#else
1413#define DEV_PM_OPS	NULL
1414#endif /* CONFIG_PM_SLEEP */
1415
1416static struct platform_driver rspi_driver = {
1417	.probe =	rspi_probe,
1418	.remove =	rspi_remove,
1419	.id_table =	spi_driver_ids,
1420	.driver		= {
1421		.name = "renesas_spi",
1422		.pm = DEV_PM_OPS,
1423		.of_match_table = of_match_ptr(rspi_of_match),
1424	},
1425};
1426module_platform_driver(rspi_driver);
1427
1428MODULE_DESCRIPTION("Renesas RSPI bus driver");
1429MODULE_LICENSE("GPL v2");
1430MODULE_AUTHOR("Yoshihiro Shimoda");
1431MODULE_ALIAS("platform:rspi");
1432