1// SPDX-License-Identifier: GPL-2.0+
2//
3// Copyright (c) 2009 Samsung Electronics Co., Ltd.
4//      Jaswinder Singh <jassi.brar@samsung.com>
5
6#include <linux/init.h>
7#include <linux/module.h>
8#include <linux/interrupt.h>
9#include <linux/delay.h>
10#include <linux/clk.h>
11#include <linux/dma-mapping.h>
12#include <linux/dmaengine.h>
13#include <linux/platform_device.h>
14#include <linux/pm_runtime.h>
15#include <linux/spi/spi.h>
16#include <linux/gpio.h>
17#include <linux/of.h>
18#include <linux/of_gpio.h>
19
20#include <linux/platform_data/spi-s3c64xx.h>
21
22#define MAX_SPI_PORTS		6
23#define S3C64XX_SPI_QUIRK_POLL		(1 << 0)
24#define S3C64XX_SPI_QUIRK_CS_AUTO	(1 << 1)
25#define AUTOSUSPEND_TIMEOUT	2000
26
27/* Registers and bit-fields */
28
29#define S3C64XX_SPI_CH_CFG		0x00
30#define S3C64XX_SPI_CLK_CFG		0x04
31#define S3C64XX_SPI_MODE_CFG		0x08
32#define S3C64XX_SPI_CS_REG		0x0C
33#define S3C64XX_SPI_INT_EN		0x10
34#define S3C64XX_SPI_STATUS		0x14
35#define S3C64XX_SPI_TX_DATA		0x18
36#define S3C64XX_SPI_RX_DATA		0x1C
37#define S3C64XX_SPI_PACKET_CNT		0x20
38#define S3C64XX_SPI_PENDING_CLR		0x24
39#define S3C64XX_SPI_SWAP_CFG		0x28
40#define S3C64XX_SPI_FB_CLK		0x2C
41
42#define S3C64XX_SPI_CH_HS_EN		(1<<6)	/* High Speed Enable */
43#define S3C64XX_SPI_CH_SW_RST		(1<<5)
44#define S3C64XX_SPI_CH_SLAVE		(1<<4)
45#define S3C64XX_SPI_CPOL_L		(1<<3)
46#define S3C64XX_SPI_CPHA_B		(1<<2)
47#define S3C64XX_SPI_CH_RXCH_ON		(1<<1)
48#define S3C64XX_SPI_CH_TXCH_ON		(1<<0)
49
50#define S3C64XX_SPI_CLKSEL_SRCMSK	(3<<9)
51#define S3C64XX_SPI_CLKSEL_SRCSHFT	9
52#define S3C64XX_SPI_ENCLK_ENABLE	(1<<8)
53#define S3C64XX_SPI_PSR_MASK		0xff
54
55#define S3C64XX_SPI_MODE_CH_TSZ_BYTE		(0<<29)
56#define S3C64XX_SPI_MODE_CH_TSZ_HALFWORD	(1<<29)
57#define S3C64XX_SPI_MODE_CH_TSZ_WORD		(2<<29)
58#define S3C64XX_SPI_MODE_CH_TSZ_MASK		(3<<29)
59#define S3C64XX_SPI_MODE_BUS_TSZ_BYTE		(0<<17)
60#define S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD	(1<<17)
61#define S3C64XX_SPI_MODE_BUS_TSZ_WORD		(2<<17)
62#define S3C64XX_SPI_MODE_BUS_TSZ_MASK		(3<<17)
63#define S3C64XX_SPI_MODE_RXDMA_ON		(1<<2)
64#define S3C64XX_SPI_MODE_TXDMA_ON		(1<<1)
65#define S3C64XX_SPI_MODE_4BURST			(1<<0)
66
67#define S3C64XX_SPI_CS_NSC_CNT_2		(2<<4)
68#define S3C64XX_SPI_CS_AUTO			(1<<1)
69#define S3C64XX_SPI_CS_SIG_INACT		(1<<0)
70
71#define S3C64XX_SPI_INT_TRAILING_EN		(1<<6)
72#define S3C64XX_SPI_INT_RX_OVERRUN_EN		(1<<5)
73#define S3C64XX_SPI_INT_RX_UNDERRUN_EN		(1<<4)
74#define S3C64XX_SPI_INT_TX_OVERRUN_EN		(1<<3)
75#define S3C64XX_SPI_INT_TX_UNDERRUN_EN		(1<<2)
76#define S3C64XX_SPI_INT_RX_FIFORDY_EN		(1<<1)
77#define S3C64XX_SPI_INT_TX_FIFORDY_EN		(1<<0)
78
79#define S3C64XX_SPI_ST_RX_OVERRUN_ERR		(1<<5)
80#define S3C64XX_SPI_ST_RX_UNDERRUN_ERR		(1<<4)
81#define S3C64XX_SPI_ST_TX_OVERRUN_ERR		(1<<3)
82#define S3C64XX_SPI_ST_TX_UNDERRUN_ERR		(1<<2)
83#define S3C64XX_SPI_ST_RX_FIFORDY		(1<<1)
84#define S3C64XX_SPI_ST_TX_FIFORDY		(1<<0)
85
86#define S3C64XX_SPI_PACKET_CNT_EN		(1<<16)
87#define S3C64XX_SPI_PACKET_CNT_MASK		GENMASK(15, 0)
88
89#define S3C64XX_SPI_PND_TX_UNDERRUN_CLR		(1<<4)
90#define S3C64XX_SPI_PND_TX_OVERRUN_CLR		(1<<3)
91#define S3C64XX_SPI_PND_RX_UNDERRUN_CLR		(1<<2)
92#define S3C64XX_SPI_PND_RX_OVERRUN_CLR		(1<<1)
93#define S3C64XX_SPI_PND_TRAILING_CLR		(1<<0)
94
95#define S3C64XX_SPI_SWAP_RX_HALF_WORD		(1<<7)
96#define S3C64XX_SPI_SWAP_RX_BYTE		(1<<6)
97#define S3C64XX_SPI_SWAP_RX_BIT			(1<<5)
98#define S3C64XX_SPI_SWAP_RX_EN			(1<<4)
99#define S3C64XX_SPI_SWAP_TX_HALF_WORD		(1<<3)
100#define S3C64XX_SPI_SWAP_TX_BYTE		(1<<2)
101#define S3C64XX_SPI_SWAP_TX_BIT			(1<<1)
102#define S3C64XX_SPI_SWAP_TX_EN			(1<<0)
103
104#define S3C64XX_SPI_FBCLK_MSK			(3<<0)
105
106#define FIFO_LVL_MASK(i) ((i)->port_conf->fifo_lvl_mask[i->port_id])
107#define S3C64XX_SPI_ST_TX_DONE(v, i) (((v) & \
108				(1 << (i)->port_conf->tx_st_done)) ? 1 : 0)
109#define TX_FIFO_LVL(v, i) (((v) >> 6) & FIFO_LVL_MASK(i))
110#define RX_FIFO_LVL(v, i) (((v) >> (i)->port_conf->rx_lvl_offset) & \
111					FIFO_LVL_MASK(i))
112
113#define S3C64XX_SPI_MAX_TRAILCNT	0x3ff
114#define S3C64XX_SPI_TRAILCNT_OFF	19
115
116#define S3C64XX_SPI_TRAILCNT		S3C64XX_SPI_MAX_TRAILCNT
117
118#define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
119#define is_polling(x)	(x->port_conf->quirks & S3C64XX_SPI_QUIRK_POLL)
120
121#define RXBUSY    (1<<2)
122#define TXBUSY    (1<<3)
123
124struct s3c64xx_spi_dma_data {
125	struct dma_chan *ch;
126	dma_cookie_t cookie;
127	enum dma_transfer_direction direction;
128};
129
130/**
131 * struct s3c64xx_spi_info - SPI Controller hardware info
132 * @fifo_lvl_mask: Bit-mask for {TX|RX}_FIFO_LVL bits in SPI_STATUS register.
133 * @rx_lvl_offset: Bit offset of RX_FIFO_LVL bits in SPI_STATUS regiter.
134 * @tx_st_done: Bit offset of TX_DONE bit in SPI_STATUS regiter.
135 * @quirks: Bitmask of known quirks
136 * @high_speed: True, if the controller supports HIGH_SPEED_EN bit.
137 * @clk_from_cmu: True, if the controller does not include a clock mux and
138 *	prescaler unit.
139 * @clk_ioclk: True if clock is present on this device
140 *
141 * The Samsung s3c64xx SPI controller are used on various Samsung SoC's but
142 * differ in some aspects such as the size of the fifo and spi bus clock
143 * setup. Such differences are specified to the driver using this structure
144 * which is provided as driver data to the driver.
145 */
146struct s3c64xx_spi_port_config {
147	int	fifo_lvl_mask[MAX_SPI_PORTS];
148	int	rx_lvl_offset;
149	int	tx_st_done;
150	int	quirks;
151	bool	high_speed;
152	bool	clk_from_cmu;
153	bool	clk_ioclk;
154};
155
156/**
157 * struct s3c64xx_spi_driver_data - Runtime info holder for SPI driver.
158 * @clk: Pointer to the spi clock.
159 * @src_clk: Pointer to the clock used to generate SPI signals.
160 * @ioclk: Pointer to the i/o clock between master and slave
161 * @pdev: Pointer to device's platform device data
162 * @master: Pointer to the SPI Protocol master.
163 * @cntrlr_info: Platform specific data for the controller this driver manages.
164 * @lock: Controller specific lock.
165 * @state: Set of FLAGS to indicate status.
166 * @sfr_start: BUS address of SPI controller regs.
167 * @regs: Pointer to ioremap'ed controller registers.
168 * @xfer_completion: To indicate completion of xfer task.
169 * @cur_mode: Stores the active configuration of the controller.
170 * @cur_bpw: Stores the active bits per word settings.
171 * @cur_speed: Current clock speed
172 * @rx_dma: Local receive DMA data (e.g. chan and direction)
173 * @tx_dma: Local transmit DMA data (e.g. chan and direction)
174 * @port_conf: Local SPI port configuartion data
175 * @port_id: Port identification number
176 */
177struct s3c64xx_spi_driver_data {
178	void __iomem                    *regs;
179	struct clk                      *clk;
180	struct clk                      *src_clk;
181	struct clk                      *ioclk;
182	struct platform_device          *pdev;
183	struct spi_master               *master;
184	struct s3c64xx_spi_info         *cntrlr_info;
185	spinlock_t                      lock;
186	unsigned long                   sfr_start;
187	struct completion               xfer_completion;
188	unsigned                        state;
189	unsigned                        cur_mode, cur_bpw;
190	unsigned                        cur_speed;
191	struct s3c64xx_spi_dma_data	rx_dma;
192	struct s3c64xx_spi_dma_data	tx_dma;
193	struct s3c64xx_spi_port_config	*port_conf;
194	unsigned int			port_id;
195};
196
197static void s3c64xx_flush_fifo(struct s3c64xx_spi_driver_data *sdd)
198{
199	void __iomem *regs = sdd->regs;
200	unsigned long loops;
201	u32 val;
202
203	writel(0, regs + S3C64XX_SPI_PACKET_CNT);
204
205	val = readl(regs + S3C64XX_SPI_CH_CFG);
206	val &= ~(S3C64XX_SPI_CH_RXCH_ON | S3C64XX_SPI_CH_TXCH_ON);
207	writel(val, regs + S3C64XX_SPI_CH_CFG);
208
209	val = readl(regs + S3C64XX_SPI_CH_CFG);
210	val |= S3C64XX_SPI_CH_SW_RST;
211	val &= ~S3C64XX_SPI_CH_HS_EN;
212	writel(val, regs + S3C64XX_SPI_CH_CFG);
213
214	/* Flush TxFIFO*/
215	loops = msecs_to_loops(1);
216	do {
217		val = readl(regs + S3C64XX_SPI_STATUS);
218	} while (TX_FIFO_LVL(val, sdd) && loops--);
219
220	if (loops == 0)
221		dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n");
222
223	/* Flush RxFIFO*/
224	loops = msecs_to_loops(1);
225	do {
226		val = readl(regs + S3C64XX_SPI_STATUS);
227		if (RX_FIFO_LVL(val, sdd))
228			readl(regs + S3C64XX_SPI_RX_DATA);
229		else
230			break;
231	} while (loops--);
232
233	if (loops == 0)
234		dev_warn(&sdd->pdev->dev, "Timed out flushing RX FIFO\n");
235
236	val = readl(regs + S3C64XX_SPI_CH_CFG);
237	val &= ~S3C64XX_SPI_CH_SW_RST;
238	writel(val, regs + S3C64XX_SPI_CH_CFG);
239
240	val = readl(regs + S3C64XX_SPI_MODE_CFG);
241	val &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
242	writel(val, regs + S3C64XX_SPI_MODE_CFG);
243}
244
245static void s3c64xx_spi_dmacb(void *data)
246{
247	struct s3c64xx_spi_driver_data *sdd;
248	struct s3c64xx_spi_dma_data *dma = data;
249	unsigned long flags;
250
251	if (dma->direction == DMA_DEV_TO_MEM)
252		sdd = container_of(data,
253			struct s3c64xx_spi_driver_data, rx_dma);
254	else
255		sdd = container_of(data,
256			struct s3c64xx_spi_driver_data, tx_dma);
257
258	spin_lock_irqsave(&sdd->lock, flags);
259
260	if (dma->direction == DMA_DEV_TO_MEM) {
261		sdd->state &= ~RXBUSY;
262		if (!(sdd->state & TXBUSY))
263			complete(&sdd->xfer_completion);
264	} else {
265		sdd->state &= ~TXBUSY;
266		if (!(sdd->state & RXBUSY))
267			complete(&sdd->xfer_completion);
268	}
269
270	spin_unlock_irqrestore(&sdd->lock, flags);
271}
272
273static int prepare_dma(struct s3c64xx_spi_dma_data *dma,
274			struct sg_table *sgt)
275{
276	struct s3c64xx_spi_driver_data *sdd;
277	struct dma_slave_config config;
278	struct dma_async_tx_descriptor *desc;
279	int ret;
280
281	memset(&config, 0, sizeof(config));
282
283	if (dma->direction == DMA_DEV_TO_MEM) {
284		sdd = container_of((void *)dma,
285			struct s3c64xx_spi_driver_data, rx_dma);
286		config.direction = dma->direction;
287		config.src_addr = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
288		config.src_addr_width = sdd->cur_bpw / 8;
289		config.src_maxburst = 1;
290		dmaengine_slave_config(dma->ch, &config);
291	} else {
292		sdd = container_of((void *)dma,
293			struct s3c64xx_spi_driver_data, tx_dma);
294		config.direction = dma->direction;
295		config.dst_addr = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
296		config.dst_addr_width = sdd->cur_bpw / 8;
297		config.dst_maxburst = 1;
298		dmaengine_slave_config(dma->ch, &config);
299	}
300
301	desc = dmaengine_prep_slave_sg(dma->ch, sgt->sgl, sgt->nents,
302				       dma->direction, DMA_PREP_INTERRUPT);
303	if (!desc) {
304		dev_err(&sdd->pdev->dev, "unable to prepare %s scatterlist",
305			dma->direction == DMA_DEV_TO_MEM ? "rx" : "tx");
306		return -ENOMEM;
307	}
308
309	desc->callback = s3c64xx_spi_dmacb;
310	desc->callback_param = dma;
311
312	dma->cookie = dmaengine_submit(desc);
313	ret = dma_submit_error(dma->cookie);
314	if (ret) {
315		dev_err(&sdd->pdev->dev, "DMA submission failed");
316		return -EIO;
317	}
318
319	dma_async_issue_pending(dma->ch);
320	return 0;
321}
322
323static void s3c64xx_spi_set_cs(struct spi_device *spi, bool enable)
324{
325	struct s3c64xx_spi_driver_data *sdd =
326					spi_master_get_devdata(spi->master);
327
328	if (sdd->cntrlr_info->no_cs)
329		return;
330
331	if (enable) {
332		if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO)) {
333			writel(0, sdd->regs + S3C64XX_SPI_CS_REG);
334		} else {
335			u32 ssel = readl(sdd->regs + S3C64XX_SPI_CS_REG);
336
337			ssel |= (S3C64XX_SPI_CS_AUTO |
338						S3C64XX_SPI_CS_NSC_CNT_2);
339			writel(ssel, sdd->regs + S3C64XX_SPI_CS_REG);
340		}
341	} else {
342		if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
343			writel(S3C64XX_SPI_CS_SIG_INACT,
344			       sdd->regs + S3C64XX_SPI_CS_REG);
345	}
346}
347
348static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
349{
350	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
351
352	if (is_polling(sdd))
353		return 0;
354
355	spi->dma_rx = sdd->rx_dma.ch;
356	spi->dma_tx = sdd->tx_dma.ch;
357
358	return 0;
359}
360
361static bool s3c64xx_spi_can_dma(struct spi_master *master,
362				struct spi_device *spi,
363				struct spi_transfer *xfer)
364{
365	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
366
367	return xfer->len > (FIFO_LVL_MASK(sdd) >> 1) + 1;
368}
369
370static int s3c64xx_enable_datapath(struct s3c64xx_spi_driver_data *sdd,
371				    struct spi_transfer *xfer, int dma_mode)
372{
373	void __iomem *regs = sdd->regs;
374	u32 modecfg, chcfg;
375	int ret = 0;
376
377	modecfg = readl(regs + S3C64XX_SPI_MODE_CFG);
378	modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
379
380	chcfg = readl(regs + S3C64XX_SPI_CH_CFG);
381	chcfg &= ~S3C64XX_SPI_CH_TXCH_ON;
382
383	if (dma_mode) {
384		chcfg &= ~S3C64XX_SPI_CH_RXCH_ON;
385	} else {
386		/* Always shift in data in FIFO, even if xfer is Tx only,
387		 * this helps setting PCKT_CNT value for generating clocks
388		 * as exactly needed.
389		 */
390		chcfg |= S3C64XX_SPI_CH_RXCH_ON;
391		writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
392					| S3C64XX_SPI_PACKET_CNT_EN,
393					regs + S3C64XX_SPI_PACKET_CNT);
394	}
395
396	if (xfer->tx_buf != NULL) {
397		sdd->state |= TXBUSY;
398		chcfg |= S3C64XX_SPI_CH_TXCH_ON;
399		if (dma_mode) {
400			modecfg |= S3C64XX_SPI_MODE_TXDMA_ON;
401			ret = prepare_dma(&sdd->tx_dma, &xfer->tx_sg);
402		} else {
403			switch (sdd->cur_bpw) {
404			case 32:
405				iowrite32_rep(regs + S3C64XX_SPI_TX_DATA,
406					xfer->tx_buf, xfer->len / 4);
407				break;
408			case 16:
409				iowrite16_rep(regs + S3C64XX_SPI_TX_DATA,
410					xfer->tx_buf, xfer->len / 2);
411				break;
412			default:
413				iowrite8_rep(regs + S3C64XX_SPI_TX_DATA,
414					xfer->tx_buf, xfer->len);
415				break;
416			}
417		}
418	}
419
420	if (xfer->rx_buf != NULL) {
421		sdd->state |= RXBUSY;
422
423		if (sdd->port_conf->high_speed && sdd->cur_speed >= 30000000UL
424					&& !(sdd->cur_mode & SPI_CPHA))
425			chcfg |= S3C64XX_SPI_CH_HS_EN;
426
427		if (dma_mode) {
428			modecfg |= S3C64XX_SPI_MODE_RXDMA_ON;
429			chcfg |= S3C64XX_SPI_CH_RXCH_ON;
430			writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
431					| S3C64XX_SPI_PACKET_CNT_EN,
432					regs + S3C64XX_SPI_PACKET_CNT);
433			ret = prepare_dma(&sdd->rx_dma, &xfer->rx_sg);
434		}
435	}
436
437	if (ret)
438		return ret;
439
440	writel(modecfg, regs + S3C64XX_SPI_MODE_CFG);
441	writel(chcfg, regs + S3C64XX_SPI_CH_CFG);
442
443	return 0;
444}
445
446static u32 s3c64xx_spi_wait_for_timeout(struct s3c64xx_spi_driver_data *sdd,
447					int timeout_ms)
448{
449	void __iomem *regs = sdd->regs;
450	unsigned long val = 1;
451	u32 status;
452
453	/* max fifo depth available */
454	u32 max_fifo = (FIFO_LVL_MASK(sdd) >> 1) + 1;
455
456	if (timeout_ms)
457		val = msecs_to_loops(timeout_ms);
458
459	do {
460		status = readl(regs + S3C64XX_SPI_STATUS);
461	} while (RX_FIFO_LVL(status, sdd) < max_fifo && --val);
462
463	/* return the actual received data length */
464	return RX_FIFO_LVL(status, sdd);
465}
466
467static int s3c64xx_wait_for_dma(struct s3c64xx_spi_driver_data *sdd,
468				struct spi_transfer *xfer)
469{
470	void __iomem *regs = sdd->regs;
471	unsigned long val;
472	u32 status;
473	int ms;
474
475	/* millisecs to xfer 'len' bytes @ 'cur_speed' */
476	ms = xfer->len * 8 * 1000 / sdd->cur_speed;
477	ms += 30;               /* some tolerance */
478	ms = max(ms, 100);      /* minimum timeout */
479
480	val = msecs_to_jiffies(ms) + 10;
481	val = wait_for_completion_timeout(&sdd->xfer_completion, val);
482
483	/*
484	 * If the previous xfer was completed within timeout, then
485	 * proceed further else return -EIO.
486	 * DmaTx returns after simply writing data in the FIFO,
487	 * w/o waiting for real transmission on the bus to finish.
488	 * DmaRx returns only after Dma read data from FIFO which
489	 * needs bus transmission to finish, so we don't worry if
490	 * Xfer involved Rx(with or without Tx).
491	 */
492	if (val && !xfer->rx_buf) {
493		val = msecs_to_loops(10);
494		status = readl(regs + S3C64XX_SPI_STATUS);
495		while ((TX_FIFO_LVL(status, sdd)
496			|| !S3C64XX_SPI_ST_TX_DONE(status, sdd))
497		       && --val) {
498			cpu_relax();
499			status = readl(regs + S3C64XX_SPI_STATUS);
500		}
501
502	}
503
504	/* If timed out while checking rx/tx status return error */
505	if (!val)
506		return -EIO;
507
508	return 0;
509}
510
511static int s3c64xx_wait_for_pio(struct s3c64xx_spi_driver_data *sdd,
512				struct spi_transfer *xfer)
513{
514	void __iomem *regs = sdd->regs;
515	unsigned long val;
516	u32 status;
517	int loops;
518	u32 cpy_len;
519	u8 *buf;
520	int ms;
521
522	/* millisecs to xfer 'len' bytes @ 'cur_speed' */
523	ms = xfer->len * 8 * 1000 / sdd->cur_speed;
524	ms += 10; /* some tolerance */
525
526	val = msecs_to_loops(ms);
527	do {
528		status = readl(regs + S3C64XX_SPI_STATUS);
529	} while (RX_FIFO_LVL(status, sdd) < xfer->len && --val);
530
531	if (!val)
532		return -EIO;
533
534	/* If it was only Tx */
535	if (!xfer->rx_buf) {
536		sdd->state &= ~TXBUSY;
537		return 0;
538	}
539
540	/*
541	 * If the receive length is bigger than the controller fifo
542	 * size, calculate the loops and read the fifo as many times.
543	 * loops = length / max fifo size (calculated by using the
544	 * fifo mask).
545	 * For any size less than the fifo size the below code is
546	 * executed atleast once.
547	 */
548	loops = xfer->len / ((FIFO_LVL_MASK(sdd) >> 1) + 1);
549	buf = xfer->rx_buf;
550	do {
551		/* wait for data to be received in the fifo */
552		cpy_len = s3c64xx_spi_wait_for_timeout(sdd,
553						       (loops ? ms : 0));
554
555		switch (sdd->cur_bpw) {
556		case 32:
557			ioread32_rep(regs + S3C64XX_SPI_RX_DATA,
558				     buf, cpy_len / 4);
559			break;
560		case 16:
561			ioread16_rep(regs + S3C64XX_SPI_RX_DATA,
562				     buf, cpy_len / 2);
563			break;
564		default:
565			ioread8_rep(regs + S3C64XX_SPI_RX_DATA,
566				    buf, cpy_len);
567			break;
568		}
569
570		buf = buf + cpy_len;
571	} while (loops--);
572	sdd->state &= ~RXBUSY;
573
574	return 0;
575}
576
577static int s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
578{
579	void __iomem *regs = sdd->regs;
580	int ret;
581	u32 val;
582
583	/* Disable Clock */
584	if (!sdd->port_conf->clk_from_cmu) {
585		val = readl(regs + S3C64XX_SPI_CLK_CFG);
586		val &= ~S3C64XX_SPI_ENCLK_ENABLE;
587		writel(val, regs + S3C64XX_SPI_CLK_CFG);
588	}
589
590	/* Set Polarity and Phase */
591	val = readl(regs + S3C64XX_SPI_CH_CFG);
592	val &= ~(S3C64XX_SPI_CH_SLAVE |
593			S3C64XX_SPI_CPOL_L |
594			S3C64XX_SPI_CPHA_B);
595
596	if (sdd->cur_mode & SPI_CPOL)
597		val |= S3C64XX_SPI_CPOL_L;
598
599	if (sdd->cur_mode & SPI_CPHA)
600		val |= S3C64XX_SPI_CPHA_B;
601
602	writel(val, regs + S3C64XX_SPI_CH_CFG);
603
604	/* Set Channel & DMA Mode */
605	val = readl(regs + S3C64XX_SPI_MODE_CFG);
606	val &= ~(S3C64XX_SPI_MODE_BUS_TSZ_MASK
607			| S3C64XX_SPI_MODE_CH_TSZ_MASK);
608
609	switch (sdd->cur_bpw) {
610	case 32:
611		val |= S3C64XX_SPI_MODE_BUS_TSZ_WORD;
612		val |= S3C64XX_SPI_MODE_CH_TSZ_WORD;
613		break;
614	case 16:
615		val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD;
616		val |= S3C64XX_SPI_MODE_CH_TSZ_HALFWORD;
617		break;
618	default:
619		val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE;
620		val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE;
621		break;
622	}
623
624	writel(val, regs + S3C64XX_SPI_MODE_CFG);
625
626	if (sdd->port_conf->clk_from_cmu) {
627		/* The src_clk clock is divided internally by 2 */
628		ret = clk_set_rate(sdd->src_clk, sdd->cur_speed * 2);
629		if (ret)
630			return ret;
631		sdd->cur_speed = clk_get_rate(sdd->src_clk) / 2;
632	} else {
633		/* Configure Clock */
634		val = readl(regs + S3C64XX_SPI_CLK_CFG);
635		val &= ~S3C64XX_SPI_PSR_MASK;
636		val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / 2 - 1)
637				& S3C64XX_SPI_PSR_MASK);
638		writel(val, regs + S3C64XX_SPI_CLK_CFG);
639
640		/* Enable Clock */
641		val = readl(regs + S3C64XX_SPI_CLK_CFG);
642		val |= S3C64XX_SPI_ENCLK_ENABLE;
643		writel(val, regs + S3C64XX_SPI_CLK_CFG);
644	}
645
646	return 0;
647}
648
649#define XFER_DMAADDR_INVALID DMA_BIT_MASK(32)
650
651static int s3c64xx_spi_prepare_message(struct spi_master *master,
652				       struct spi_message *msg)
653{
654	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
655	struct spi_device *spi = msg->spi;
656	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
657
658	/* Configure feedback delay */
659	writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK);
660
661	return 0;
662}
663
664static size_t s3c64xx_spi_max_transfer_size(struct spi_device *spi)
665{
666	struct spi_controller *ctlr = spi->controller;
667
668	return ctlr->can_dma ? S3C64XX_SPI_PACKET_CNT_MASK : SIZE_MAX;
669}
670
671static int s3c64xx_spi_transfer_one(struct spi_master *master,
672				    struct spi_device *spi,
673				    struct spi_transfer *xfer)
674{
675	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
676	const unsigned int fifo_len = (FIFO_LVL_MASK(sdd) >> 1) + 1;
677	const void *tx_buf = NULL;
678	void *rx_buf = NULL;
679	int target_len = 0, origin_len = 0;
680	int use_dma = 0;
681	int status;
682	u32 speed;
683	u8 bpw;
684	unsigned long flags;
685
686	reinit_completion(&sdd->xfer_completion);
687
688	/* Only BPW and Speed may change across transfers */
689	bpw = xfer->bits_per_word;
690	speed = xfer->speed_hz;
691
692	if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) {
693		sdd->cur_bpw = bpw;
694		sdd->cur_speed = speed;
695		sdd->cur_mode = spi->mode;
696		status = s3c64xx_spi_config(sdd);
697		if (status)
698			return status;
699	}
700
701	if (!is_polling(sdd) && (xfer->len > fifo_len) &&
702	    sdd->rx_dma.ch && sdd->tx_dma.ch) {
703		use_dma = 1;
704
705	} else if (is_polling(sdd) && xfer->len > fifo_len) {
706		tx_buf = xfer->tx_buf;
707		rx_buf = xfer->rx_buf;
708		origin_len = xfer->len;
709
710		target_len = xfer->len;
711		if (xfer->len > fifo_len)
712			xfer->len = fifo_len;
713	}
714
715	do {
716		spin_lock_irqsave(&sdd->lock, flags);
717
718		/* Pending only which is to be done */
719		sdd->state &= ~RXBUSY;
720		sdd->state &= ~TXBUSY;
721
722		/* Start the signals */
723		s3c64xx_spi_set_cs(spi, true);
724
725		status = s3c64xx_enable_datapath(sdd, xfer, use_dma);
726
727		spin_unlock_irqrestore(&sdd->lock, flags);
728
729		if (status) {
730			dev_err(&spi->dev, "failed to enable data path for transfer: %d\n", status);
731			break;
732		}
733
734		if (use_dma)
735			status = s3c64xx_wait_for_dma(sdd, xfer);
736		else
737			status = s3c64xx_wait_for_pio(sdd, xfer);
738
739		if (status) {
740			dev_err(&spi->dev,
741				"I/O Error: rx-%d tx-%d rx-%c tx-%c len-%d dma-%d res-(%d)\n",
742				xfer->rx_buf ? 1 : 0, xfer->tx_buf ? 1 : 0,
743				(sdd->state & RXBUSY) ? 'f' : 'p',
744				(sdd->state & TXBUSY) ? 'f' : 'p',
745				xfer->len, use_dma ? 1 : 0, status);
746
747			if (use_dma) {
748				struct dma_tx_state s;
749
750				if (xfer->tx_buf && (sdd->state & TXBUSY)) {
751					dmaengine_pause(sdd->tx_dma.ch);
752					dmaengine_tx_status(sdd->tx_dma.ch, sdd->tx_dma.cookie, &s);
753					dmaengine_terminate_all(sdd->tx_dma.ch);
754					dev_err(&spi->dev, "TX residue: %d\n", s.residue);
755
756				}
757				if (xfer->rx_buf && (sdd->state & RXBUSY)) {
758					dmaengine_pause(sdd->rx_dma.ch);
759					dmaengine_tx_status(sdd->rx_dma.ch, sdd->rx_dma.cookie, &s);
760					dmaengine_terminate_all(sdd->rx_dma.ch);
761					dev_err(&spi->dev, "RX residue: %d\n", s.residue);
762				}
763			}
764		} else {
765			s3c64xx_flush_fifo(sdd);
766		}
767		if (target_len > 0) {
768			target_len -= xfer->len;
769
770			if (xfer->tx_buf)
771				xfer->tx_buf += xfer->len;
772
773			if (xfer->rx_buf)
774				xfer->rx_buf += xfer->len;
775
776			if (target_len > fifo_len)
777				xfer->len = fifo_len;
778			else
779				xfer->len = target_len;
780		}
781	} while (target_len > 0);
782
783	if (origin_len) {
784		/* Restore original xfer buffers and length */
785		xfer->tx_buf = tx_buf;
786		xfer->rx_buf = rx_buf;
787		xfer->len = origin_len;
788	}
789
790	return status;
791}
792
793static struct s3c64xx_spi_csinfo *s3c64xx_get_slave_ctrldata(
794				struct spi_device *spi)
795{
796	struct s3c64xx_spi_csinfo *cs;
797	struct device_node *slave_np, *data_np = NULL;
798	u32 fb_delay = 0;
799
800	slave_np = spi->dev.of_node;
801	if (!slave_np) {
802		dev_err(&spi->dev, "device node not found\n");
803		return ERR_PTR(-EINVAL);
804	}
805
806	data_np = of_get_child_by_name(slave_np, "controller-data");
807	if (!data_np) {
808		dev_err(&spi->dev, "child node 'controller-data' not found\n");
809		return ERR_PTR(-EINVAL);
810	}
811
812	cs = kzalloc(sizeof(*cs), GFP_KERNEL);
813	if (!cs) {
814		of_node_put(data_np);
815		return ERR_PTR(-ENOMEM);
816	}
817
818	of_property_read_u32(data_np, "samsung,spi-feedback-delay", &fb_delay);
819	cs->fb_delay = fb_delay;
820	of_node_put(data_np);
821	return cs;
822}
823
824/*
825 * Here we only check the validity of requested configuration
826 * and save the configuration in a local data-structure.
827 * The controller is actually configured only just before we
828 * get a message to transfer.
829 */
830static int s3c64xx_spi_setup(struct spi_device *spi)
831{
832	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
833	struct s3c64xx_spi_driver_data *sdd;
834	int err;
835
836	sdd = spi_master_get_devdata(spi->master);
837	if (spi->dev.of_node) {
838		cs = s3c64xx_get_slave_ctrldata(spi);
839		spi->controller_data = cs;
840	} else if (cs) {
841		/* On non-DT platforms the SPI core will set spi->cs_gpio
842		 * to -ENOENT. The GPIO pin used to drive the chip select
843		 * is defined by using platform data so spi->cs_gpio value
844		 * has to be override to have the proper GPIO pin number.
845		 */
846		spi->cs_gpio = cs->line;
847	}
848
849	if (IS_ERR_OR_NULL(cs)) {
850		dev_err(&spi->dev, "No CS for SPI(%d)\n", spi->chip_select);
851		return -ENODEV;
852	}
853
854	if (!spi_get_ctldata(spi)) {
855		if (gpio_is_valid(spi->cs_gpio)) {
856			err = gpio_request_one(spi->cs_gpio, GPIOF_OUT_INIT_HIGH,
857					       dev_name(&spi->dev));
858			if (err) {
859				dev_err(&spi->dev,
860					"Failed to get /CS gpio [%d]: %d\n",
861					spi->cs_gpio, err);
862				goto err_gpio_req;
863			}
864		}
865
866		spi_set_ctldata(spi, cs);
867	}
868
869	pm_runtime_get_sync(&sdd->pdev->dev);
870
871	/* Check if we can provide the requested rate */
872	if (!sdd->port_conf->clk_from_cmu) {
873		u32 psr, speed;
874
875		/* Max possible */
876		speed = clk_get_rate(sdd->src_clk) / 2 / (0 + 1);
877
878		if (spi->max_speed_hz > speed)
879			spi->max_speed_hz = speed;
880
881		psr = clk_get_rate(sdd->src_clk) / 2 / spi->max_speed_hz - 1;
882		psr &= S3C64XX_SPI_PSR_MASK;
883		if (psr == S3C64XX_SPI_PSR_MASK)
884			psr--;
885
886		speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
887		if (spi->max_speed_hz < speed) {
888			if (psr+1 < S3C64XX_SPI_PSR_MASK) {
889				psr++;
890			} else {
891				err = -EINVAL;
892				goto setup_exit;
893			}
894		}
895
896		speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
897		if (spi->max_speed_hz >= speed) {
898			spi->max_speed_hz = speed;
899		} else {
900			dev_err(&spi->dev, "Can't set %dHz transfer speed\n",
901				spi->max_speed_hz);
902			err = -EINVAL;
903			goto setup_exit;
904		}
905	}
906
907	pm_runtime_mark_last_busy(&sdd->pdev->dev);
908	pm_runtime_put_autosuspend(&sdd->pdev->dev);
909	s3c64xx_spi_set_cs(spi, false);
910
911	return 0;
912
913setup_exit:
914	pm_runtime_mark_last_busy(&sdd->pdev->dev);
915	pm_runtime_put_autosuspend(&sdd->pdev->dev);
916	/* setup() returns with device de-selected */
917	s3c64xx_spi_set_cs(spi, false);
918
919	if (gpio_is_valid(spi->cs_gpio))
920		gpio_free(spi->cs_gpio);
921	spi_set_ctldata(spi, NULL);
922
923err_gpio_req:
924	if (spi->dev.of_node)
925		kfree(cs);
926
927	return err;
928}
929
930static void s3c64xx_spi_cleanup(struct spi_device *spi)
931{
932	struct s3c64xx_spi_csinfo *cs = spi_get_ctldata(spi);
933
934	if (gpio_is_valid(spi->cs_gpio)) {
935		gpio_free(spi->cs_gpio);
936		if (spi->dev.of_node)
937			kfree(cs);
938		else {
939			/* On non-DT platforms, the SPI core sets
940			 * spi->cs_gpio to -ENOENT and .setup()
941			 * overrides it with the GPIO pin value
942			 * passed using platform data.
943			 */
944			spi->cs_gpio = -ENOENT;
945		}
946	}
947
948	spi_set_ctldata(spi, NULL);
949}
950
951static irqreturn_t s3c64xx_spi_irq(int irq, void *data)
952{
953	struct s3c64xx_spi_driver_data *sdd = data;
954	struct spi_master *spi = sdd->master;
955	unsigned int val, clr = 0;
956
957	val = readl(sdd->regs + S3C64XX_SPI_STATUS);
958
959	if (val & S3C64XX_SPI_ST_RX_OVERRUN_ERR) {
960		clr = S3C64XX_SPI_PND_RX_OVERRUN_CLR;
961		dev_err(&spi->dev, "RX overrun\n");
962	}
963	if (val & S3C64XX_SPI_ST_RX_UNDERRUN_ERR) {
964		clr |= S3C64XX_SPI_PND_RX_UNDERRUN_CLR;
965		dev_err(&spi->dev, "RX underrun\n");
966	}
967	if (val & S3C64XX_SPI_ST_TX_OVERRUN_ERR) {
968		clr |= S3C64XX_SPI_PND_TX_OVERRUN_CLR;
969		dev_err(&spi->dev, "TX overrun\n");
970	}
971	if (val & S3C64XX_SPI_ST_TX_UNDERRUN_ERR) {
972		clr |= S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
973		dev_err(&spi->dev, "TX underrun\n");
974	}
975
976	/* Clear the pending irq by setting and then clearing it */
977	writel(clr, sdd->regs + S3C64XX_SPI_PENDING_CLR);
978	writel(0, sdd->regs + S3C64XX_SPI_PENDING_CLR);
979
980	return IRQ_HANDLED;
981}
982
983static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd)
984{
985	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
986	void __iomem *regs = sdd->regs;
987	unsigned int val;
988
989	sdd->cur_speed = 0;
990
991	if (sci->no_cs)
992		writel(0, sdd->regs + S3C64XX_SPI_CS_REG);
993	else if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
994		writel(S3C64XX_SPI_CS_SIG_INACT, sdd->regs + S3C64XX_SPI_CS_REG);
995
996	/* Disable Interrupts - we use Polling if not DMA mode */
997	writel(0, regs + S3C64XX_SPI_INT_EN);
998
999	if (!sdd->port_conf->clk_from_cmu)
1000		writel(sci->src_clk_nr << S3C64XX_SPI_CLKSEL_SRCSHFT,
1001				regs + S3C64XX_SPI_CLK_CFG);
1002	writel(0, regs + S3C64XX_SPI_MODE_CFG);
1003	writel(0, regs + S3C64XX_SPI_PACKET_CNT);
1004
1005	/* Clear any irq pending bits, should set and clear the bits */
1006	val = S3C64XX_SPI_PND_RX_OVERRUN_CLR |
1007		S3C64XX_SPI_PND_RX_UNDERRUN_CLR |
1008		S3C64XX_SPI_PND_TX_OVERRUN_CLR |
1009		S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
1010	writel(val, regs + S3C64XX_SPI_PENDING_CLR);
1011	writel(0, regs + S3C64XX_SPI_PENDING_CLR);
1012
1013	writel(0, regs + S3C64XX_SPI_SWAP_CFG);
1014
1015	val = readl(regs + S3C64XX_SPI_MODE_CFG);
1016	val &= ~S3C64XX_SPI_MODE_4BURST;
1017	val &= ~(S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
1018	val |= (S3C64XX_SPI_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
1019	writel(val, regs + S3C64XX_SPI_MODE_CFG);
1020
1021	s3c64xx_flush_fifo(sdd);
1022}
1023
1024#ifdef CONFIG_OF
1025static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
1026{
1027	struct s3c64xx_spi_info *sci;
1028	u32 temp;
1029
1030	sci = devm_kzalloc(dev, sizeof(*sci), GFP_KERNEL);
1031	if (!sci)
1032		return ERR_PTR(-ENOMEM);
1033
1034	if (of_property_read_u32(dev->of_node, "samsung,spi-src-clk", &temp)) {
1035		dev_warn(dev, "spi bus clock parent not specified, using clock at index 0 as parent\n");
1036		sci->src_clk_nr = 0;
1037	} else {
1038		sci->src_clk_nr = temp;
1039	}
1040
1041	if (of_property_read_u32(dev->of_node, "num-cs", &temp)) {
1042		dev_warn(dev, "number of chip select lines not specified, assuming 1 chip select line\n");
1043		sci->num_cs = 1;
1044	} else {
1045		sci->num_cs = temp;
1046	}
1047
1048	sci->no_cs = of_property_read_bool(dev->of_node, "no-cs-readback");
1049
1050	return sci;
1051}
1052#else
1053static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
1054{
1055	return dev_get_platdata(dev);
1056}
1057#endif
1058
1059static const struct of_device_id s3c64xx_spi_dt_match[];
1060
1061static inline struct s3c64xx_spi_port_config *s3c64xx_spi_get_port_config(
1062						struct platform_device *pdev)
1063{
1064#ifdef CONFIG_OF
1065	if (pdev->dev.of_node) {
1066		const struct of_device_id *match;
1067		match = of_match_node(s3c64xx_spi_dt_match, pdev->dev.of_node);
1068		return (struct s3c64xx_spi_port_config *)match->data;
1069	}
1070#endif
1071	return (struct s3c64xx_spi_port_config *)
1072			 platform_get_device_id(pdev)->driver_data;
1073}
1074
1075static int s3c64xx_spi_probe(struct platform_device *pdev)
1076{
1077	struct resource	*mem_res;
1078	struct s3c64xx_spi_driver_data *sdd;
1079	struct s3c64xx_spi_info *sci = dev_get_platdata(&pdev->dev);
1080	struct spi_master *master;
1081	int ret, irq;
1082	char clk_name[16];
1083
1084	if (!sci && pdev->dev.of_node) {
1085		sci = s3c64xx_spi_parse_dt(&pdev->dev);
1086		if (IS_ERR(sci))
1087			return PTR_ERR(sci);
1088	}
1089
1090	if (!sci) {
1091		dev_err(&pdev->dev, "platform_data missing!\n");
1092		return -ENODEV;
1093	}
1094
1095	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1096	if (mem_res == NULL) {
1097		dev_err(&pdev->dev, "Unable to get SPI MEM resource\n");
1098		return -ENXIO;
1099	}
1100
1101	irq = platform_get_irq(pdev, 0);
1102	if (irq < 0) {
1103		dev_warn(&pdev->dev, "Failed to get IRQ: %d\n", irq);
1104		return irq;
1105	}
1106
1107	master = spi_alloc_master(&pdev->dev,
1108				sizeof(struct s3c64xx_spi_driver_data));
1109	if (master == NULL) {
1110		dev_err(&pdev->dev, "Unable to allocate SPI Master\n");
1111		return -ENOMEM;
1112	}
1113
1114	platform_set_drvdata(pdev, master);
1115
1116	sdd = spi_master_get_devdata(master);
1117	sdd->port_conf = s3c64xx_spi_get_port_config(pdev);
1118	sdd->master = master;
1119	sdd->cntrlr_info = sci;
1120	sdd->pdev = pdev;
1121	sdd->sfr_start = mem_res->start;
1122	if (pdev->dev.of_node) {
1123		ret = of_alias_get_id(pdev->dev.of_node, "spi");
1124		if (ret < 0) {
1125			dev_err(&pdev->dev, "failed to get alias id, errno %d\n",
1126				ret);
1127			goto err_deref_master;
1128		}
1129		sdd->port_id = ret;
1130	} else {
1131		sdd->port_id = pdev->id;
1132	}
1133
1134	sdd->cur_bpw = 8;
1135
1136	sdd->tx_dma.direction = DMA_MEM_TO_DEV;
1137	sdd->rx_dma.direction = DMA_DEV_TO_MEM;
1138
1139	master->dev.of_node = pdev->dev.of_node;
1140	master->bus_num = sdd->port_id;
1141	master->setup = s3c64xx_spi_setup;
1142	master->cleanup = s3c64xx_spi_cleanup;
1143	master->prepare_transfer_hardware = s3c64xx_spi_prepare_transfer;
1144	master->prepare_message = s3c64xx_spi_prepare_message;
1145	master->transfer_one = s3c64xx_spi_transfer_one;
1146	master->max_transfer_size = s3c64xx_spi_max_transfer_size;
1147	master->num_chipselect = sci->num_cs;
1148	master->dma_alignment = 8;
1149	master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) |
1150					SPI_BPW_MASK(8);
1151	/* the spi->mode bits understood by this driver: */
1152	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1153	master->auto_runtime_pm = true;
1154	if (!is_polling(sdd))
1155		master->can_dma = s3c64xx_spi_can_dma;
1156
1157	sdd->regs = devm_ioremap_resource(&pdev->dev, mem_res);
1158	if (IS_ERR(sdd->regs)) {
1159		ret = PTR_ERR(sdd->regs);
1160		goto err_deref_master;
1161	}
1162
1163	if (sci->cfg_gpio && sci->cfg_gpio()) {
1164		dev_err(&pdev->dev, "Unable to config gpio\n");
1165		ret = -EBUSY;
1166		goto err_deref_master;
1167	}
1168
1169	/* Setup clocks */
1170	sdd->clk = devm_clk_get(&pdev->dev, "spi");
1171	if (IS_ERR(sdd->clk)) {
1172		dev_err(&pdev->dev, "Unable to acquire clock 'spi'\n");
1173		ret = PTR_ERR(sdd->clk);
1174		goto err_deref_master;
1175	}
1176
1177	ret = clk_prepare_enable(sdd->clk);
1178	if (ret) {
1179		dev_err(&pdev->dev, "Couldn't enable clock 'spi'\n");
1180		goto err_deref_master;
1181	}
1182
1183	sprintf(clk_name, "spi_busclk%d", sci->src_clk_nr);
1184	sdd->src_clk = devm_clk_get(&pdev->dev, clk_name);
1185	if (IS_ERR(sdd->src_clk)) {
1186		dev_err(&pdev->dev,
1187			"Unable to acquire clock '%s'\n", clk_name);
1188		ret = PTR_ERR(sdd->src_clk);
1189		goto err_disable_clk;
1190	}
1191
1192	ret = clk_prepare_enable(sdd->src_clk);
1193	if (ret) {
1194		dev_err(&pdev->dev, "Couldn't enable clock '%s'\n", clk_name);
1195		goto err_disable_clk;
1196	}
1197
1198	if (sdd->port_conf->clk_ioclk) {
1199		sdd->ioclk = devm_clk_get(&pdev->dev, "spi_ioclk");
1200		if (IS_ERR(sdd->ioclk)) {
1201			dev_err(&pdev->dev, "Unable to acquire 'ioclk'\n");
1202			ret = PTR_ERR(sdd->ioclk);
1203			goto err_disable_src_clk;
1204		}
1205
1206		ret = clk_prepare_enable(sdd->ioclk);
1207		if (ret) {
1208			dev_err(&pdev->dev, "Couldn't enable clock 'ioclk'\n");
1209			goto err_disable_src_clk;
1210		}
1211	}
1212
1213	if (!is_polling(sdd)) {
1214		/* Acquire DMA channels */
1215		sdd->rx_dma.ch = dma_request_chan(&pdev->dev, "rx");
1216		if (IS_ERR(sdd->rx_dma.ch)) {
1217			dev_err(&pdev->dev, "Failed to get RX DMA channel\n");
1218			ret = PTR_ERR(sdd->rx_dma.ch);
1219			goto err_disable_io_clk;
1220		}
1221		sdd->tx_dma.ch = dma_request_chan(&pdev->dev, "tx");
1222		if (IS_ERR(sdd->tx_dma.ch)) {
1223			dev_err(&pdev->dev, "Failed to get TX DMA channel\n");
1224			ret = PTR_ERR(sdd->tx_dma.ch);
1225			goto err_release_rx_dma;
1226		}
1227	}
1228
1229	pm_runtime_set_autosuspend_delay(&pdev->dev, AUTOSUSPEND_TIMEOUT);
1230	pm_runtime_use_autosuspend(&pdev->dev);
1231	pm_runtime_set_active(&pdev->dev);
1232	pm_runtime_enable(&pdev->dev);
1233	pm_runtime_get_sync(&pdev->dev);
1234
1235	/* Setup Deufult Mode */
1236	s3c64xx_spi_hwinit(sdd);
1237
1238	spin_lock_init(&sdd->lock);
1239	init_completion(&sdd->xfer_completion);
1240
1241	ret = devm_request_irq(&pdev->dev, irq, s3c64xx_spi_irq, 0,
1242				"spi-s3c64xx", sdd);
1243	if (ret != 0) {
1244		dev_err(&pdev->dev, "Failed to request IRQ %d: %d\n",
1245			irq, ret);
1246		goto err_pm_put;
1247	}
1248
1249	writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
1250	       S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
1251	       sdd->regs + S3C64XX_SPI_INT_EN);
1252
1253	ret = devm_spi_register_master(&pdev->dev, master);
1254	if (ret != 0) {
1255		dev_err(&pdev->dev, "cannot register SPI master: %d\n", ret);
1256		goto err_pm_put;
1257	}
1258
1259	dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d with %d Slaves attached\n",
1260					sdd->port_id, master->num_chipselect);
1261	dev_dbg(&pdev->dev, "\tIOmem=[%pR]\tFIFO %dbytes\n",
1262					mem_res, (FIFO_LVL_MASK(sdd) >> 1) + 1);
1263
1264	pm_runtime_mark_last_busy(&pdev->dev);
1265	pm_runtime_put_autosuspend(&pdev->dev);
1266
1267	return 0;
1268
1269err_pm_put:
1270	pm_runtime_put_noidle(&pdev->dev);
1271	pm_runtime_disable(&pdev->dev);
1272	pm_runtime_set_suspended(&pdev->dev);
1273
1274	if (!is_polling(sdd))
1275		dma_release_channel(sdd->tx_dma.ch);
1276err_release_rx_dma:
1277	if (!is_polling(sdd))
1278		dma_release_channel(sdd->rx_dma.ch);
1279err_disable_io_clk:
1280	clk_disable_unprepare(sdd->ioclk);
1281err_disable_src_clk:
1282	clk_disable_unprepare(sdd->src_clk);
1283err_disable_clk:
1284	clk_disable_unprepare(sdd->clk);
1285err_deref_master:
1286	spi_master_put(master);
1287
1288	return ret;
1289}
1290
1291static int s3c64xx_spi_remove(struct platform_device *pdev)
1292{
1293	struct spi_master *master = platform_get_drvdata(pdev);
1294	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1295
1296	pm_runtime_get_sync(&pdev->dev);
1297
1298	writel(0, sdd->regs + S3C64XX_SPI_INT_EN);
1299
1300	if (!is_polling(sdd)) {
1301		dma_release_channel(sdd->rx_dma.ch);
1302		dma_release_channel(sdd->tx_dma.ch);
1303	}
1304
1305	clk_disable_unprepare(sdd->ioclk);
1306
1307	clk_disable_unprepare(sdd->src_clk);
1308
1309	clk_disable_unprepare(sdd->clk);
1310
1311	pm_runtime_put_noidle(&pdev->dev);
1312	pm_runtime_disable(&pdev->dev);
1313	pm_runtime_set_suspended(&pdev->dev);
1314
1315	return 0;
1316}
1317
1318#ifdef CONFIG_PM_SLEEP
1319static int s3c64xx_spi_suspend(struct device *dev)
1320{
1321	struct spi_master *master = dev_get_drvdata(dev);
1322	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1323
1324	int ret = spi_master_suspend(master);
1325	if (ret)
1326		return ret;
1327
1328	ret = pm_runtime_force_suspend(dev);
1329	if (ret < 0)
1330		return ret;
1331
1332	sdd->cur_speed = 0; /* Output Clock is stopped */
1333
1334	return 0;
1335}
1336
1337static int s3c64xx_spi_resume(struct device *dev)
1338{
1339	struct spi_master *master = dev_get_drvdata(dev);
1340	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1341	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1342	int ret;
1343
1344	if (sci->cfg_gpio)
1345		sci->cfg_gpio();
1346
1347	ret = pm_runtime_force_resume(dev);
1348	if (ret < 0)
1349		return ret;
1350
1351	return spi_master_resume(master);
1352}
1353#endif /* CONFIG_PM_SLEEP */
1354
1355#ifdef CONFIG_PM
1356static int s3c64xx_spi_runtime_suspend(struct device *dev)
1357{
1358	struct spi_master *master = dev_get_drvdata(dev);
1359	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1360
1361	clk_disable_unprepare(sdd->clk);
1362	clk_disable_unprepare(sdd->src_clk);
1363	clk_disable_unprepare(sdd->ioclk);
1364
1365	return 0;
1366}
1367
1368static int s3c64xx_spi_runtime_resume(struct device *dev)
1369{
1370	struct spi_master *master = dev_get_drvdata(dev);
1371	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1372	int ret;
1373
1374	if (sdd->port_conf->clk_ioclk) {
1375		ret = clk_prepare_enable(sdd->ioclk);
1376		if (ret != 0)
1377			return ret;
1378	}
1379
1380	ret = clk_prepare_enable(sdd->src_clk);
1381	if (ret != 0)
1382		goto err_disable_ioclk;
1383
1384	ret = clk_prepare_enable(sdd->clk);
1385	if (ret != 0)
1386		goto err_disable_src_clk;
1387
1388	s3c64xx_spi_hwinit(sdd);
1389
1390	writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
1391	       S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
1392	       sdd->regs + S3C64XX_SPI_INT_EN);
1393
1394	return 0;
1395
1396err_disable_src_clk:
1397	clk_disable_unprepare(sdd->src_clk);
1398err_disable_ioclk:
1399	clk_disable_unprepare(sdd->ioclk);
1400
1401	return ret;
1402}
1403#endif /* CONFIG_PM */
1404
1405static const struct dev_pm_ops s3c64xx_spi_pm = {
1406	SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume)
1407	SET_RUNTIME_PM_OPS(s3c64xx_spi_runtime_suspend,
1408			   s3c64xx_spi_runtime_resume, NULL)
1409};
1410
1411static struct s3c64xx_spi_port_config s3c2443_spi_port_config = {
1412	.fifo_lvl_mask	= { 0x7f },
1413	.rx_lvl_offset	= 13,
1414	.tx_st_done	= 21,
1415	.high_speed	= true,
1416};
1417
1418static struct s3c64xx_spi_port_config s3c6410_spi_port_config = {
1419	.fifo_lvl_mask	= { 0x7f, 0x7F },
1420	.rx_lvl_offset	= 13,
1421	.tx_st_done	= 21,
1422};
1423
1424static struct s3c64xx_spi_port_config s5pv210_spi_port_config = {
1425	.fifo_lvl_mask	= { 0x1ff, 0x7F },
1426	.rx_lvl_offset	= 15,
1427	.tx_st_done	= 25,
1428	.high_speed	= true,
1429};
1430
1431static struct s3c64xx_spi_port_config exynos4_spi_port_config = {
1432	.fifo_lvl_mask	= { 0x1ff, 0x7F, 0x7F },
1433	.rx_lvl_offset	= 15,
1434	.tx_st_done	= 25,
1435	.high_speed	= true,
1436	.clk_from_cmu	= true,
1437	.quirks		= S3C64XX_SPI_QUIRK_CS_AUTO,
1438};
1439
1440static struct s3c64xx_spi_port_config exynos7_spi_port_config = {
1441	.fifo_lvl_mask	= { 0x1ff, 0x7F, 0x7F, 0x7F, 0x7F, 0x1ff},
1442	.rx_lvl_offset	= 15,
1443	.tx_st_done	= 25,
1444	.high_speed	= true,
1445	.clk_from_cmu	= true,
1446	.quirks		= S3C64XX_SPI_QUIRK_CS_AUTO,
1447};
1448
1449static struct s3c64xx_spi_port_config exynos5433_spi_port_config = {
1450	.fifo_lvl_mask	= { 0x1ff, 0x7f, 0x7f, 0x7f, 0x7f, 0x1ff},
1451	.rx_lvl_offset	= 15,
1452	.tx_st_done	= 25,
1453	.high_speed	= true,
1454	.clk_from_cmu	= true,
1455	.clk_ioclk	= true,
1456	.quirks		= S3C64XX_SPI_QUIRK_CS_AUTO,
1457};
1458
1459static const struct platform_device_id s3c64xx_spi_driver_ids[] = {
1460	{
1461		.name		= "s3c2443-spi",
1462		.driver_data	= (kernel_ulong_t)&s3c2443_spi_port_config,
1463	}, {
1464		.name		= "s3c6410-spi",
1465		.driver_data	= (kernel_ulong_t)&s3c6410_spi_port_config,
1466	},
1467	{ },
1468};
1469
1470static const struct of_device_id s3c64xx_spi_dt_match[] = {
1471	{ .compatible = "samsung,s3c2443-spi",
1472			.data = (void *)&s3c2443_spi_port_config,
1473	},
1474	{ .compatible = "samsung,s3c6410-spi",
1475			.data = (void *)&s3c6410_spi_port_config,
1476	},
1477	{ .compatible = "samsung,s5pv210-spi",
1478			.data = (void *)&s5pv210_spi_port_config,
1479	},
1480	{ .compatible = "samsung,exynos4210-spi",
1481			.data = (void *)&exynos4_spi_port_config,
1482	},
1483	{ .compatible = "samsung,exynos7-spi",
1484			.data = (void *)&exynos7_spi_port_config,
1485	},
1486	{ .compatible = "samsung,exynos5433-spi",
1487			.data = (void *)&exynos5433_spi_port_config,
1488	},
1489	{ },
1490};
1491MODULE_DEVICE_TABLE(of, s3c64xx_spi_dt_match);
1492
1493static struct platform_driver s3c64xx_spi_driver = {
1494	.driver = {
1495		.name	= "s3c64xx-spi",
1496		.pm = &s3c64xx_spi_pm,
1497		.of_match_table = of_match_ptr(s3c64xx_spi_dt_match),
1498	},
1499	.probe = s3c64xx_spi_probe,
1500	.remove = s3c64xx_spi_remove,
1501	.id_table = s3c64xx_spi_driver_ids,
1502};
1503MODULE_ALIAS("platform:s3c64xx-spi");
1504
1505module_platform_driver(s3c64xx_spi_driver);
1506
1507MODULE_AUTHOR("Jaswinder Singh <jassi.brar@samsung.com>");
1508MODULE_DESCRIPTION("S3C64XX SPI Controller Driver");
1509MODULE_LICENSE("GPL");
1510