1/*
2 * Copyright (C) 2009 Samsung Electronics Ltd.
3 *	Jaswinder Singh <jassi.brar@samsung.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 * GNU General Public License for more details.
14 */
15
16#include <linux/init.h>
17#include <linux/module.h>
18#include <linux/interrupt.h>
19#include <linux/delay.h>
20#include <linux/clk.h>
21#include <linux/dma-mapping.h>
22#include <linux/dmaengine.h>
23#include <linux/platform_device.h>
24#include <linux/pm_runtime.h>
25#include <linux/spi/spi.h>
26#include <linux/gpio.h>
27#include <linux/of.h>
28#include <linux/of_gpio.h>
29
30#include <linux/platform_data/spi-s3c64xx.h>
31
32#define MAX_SPI_PORTS		6
33#define S3C64XX_SPI_QUIRK_POLL		(1 << 0)
34#define S3C64XX_SPI_QUIRK_CS_AUTO	(1 << 1)
35
36/* Registers and bit-fields */
37
38#define S3C64XX_SPI_CH_CFG		0x00
39#define S3C64XX_SPI_CLK_CFG		0x04
40#define S3C64XX_SPI_MODE_CFG	0x08
41#define S3C64XX_SPI_SLAVE_SEL	0x0C
42#define S3C64XX_SPI_INT_EN		0x10
43#define S3C64XX_SPI_STATUS		0x14
44#define S3C64XX_SPI_TX_DATA		0x18
45#define S3C64XX_SPI_RX_DATA		0x1C
46#define S3C64XX_SPI_PACKET_CNT	0x20
47#define S3C64XX_SPI_PENDING_CLR	0x24
48#define S3C64XX_SPI_SWAP_CFG	0x28
49#define S3C64XX_SPI_FB_CLK		0x2C
50
51#define S3C64XX_SPI_CH_HS_EN		(1<<6)	/* High Speed Enable */
52#define S3C64XX_SPI_CH_SW_RST		(1<<5)
53#define S3C64XX_SPI_CH_SLAVE		(1<<4)
54#define S3C64XX_SPI_CPOL_L		(1<<3)
55#define S3C64XX_SPI_CPHA_B		(1<<2)
56#define S3C64XX_SPI_CH_RXCH_ON		(1<<1)
57#define S3C64XX_SPI_CH_TXCH_ON		(1<<0)
58
59#define S3C64XX_SPI_CLKSEL_SRCMSK	(3<<9)
60#define S3C64XX_SPI_CLKSEL_SRCSHFT	9
61#define S3C64XX_SPI_ENCLK_ENABLE	(1<<8)
62#define S3C64XX_SPI_PSR_MASK		0xff
63
64#define S3C64XX_SPI_MODE_CH_TSZ_BYTE		(0<<29)
65#define S3C64XX_SPI_MODE_CH_TSZ_HALFWORD	(1<<29)
66#define S3C64XX_SPI_MODE_CH_TSZ_WORD		(2<<29)
67#define S3C64XX_SPI_MODE_CH_TSZ_MASK		(3<<29)
68#define S3C64XX_SPI_MODE_BUS_TSZ_BYTE		(0<<17)
69#define S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD	(1<<17)
70#define S3C64XX_SPI_MODE_BUS_TSZ_WORD		(2<<17)
71#define S3C64XX_SPI_MODE_BUS_TSZ_MASK		(3<<17)
72#define S3C64XX_SPI_MODE_RXDMA_ON		(1<<2)
73#define S3C64XX_SPI_MODE_TXDMA_ON		(1<<1)
74#define S3C64XX_SPI_MODE_4BURST			(1<<0)
75
76#define S3C64XX_SPI_SLAVE_AUTO			(1<<1)
77#define S3C64XX_SPI_SLAVE_SIG_INACT		(1<<0)
78#define S3C64XX_SPI_SLAVE_NSC_CNT_2		(2<<4)
79
80#define S3C64XX_SPI_INT_TRAILING_EN		(1<<6)
81#define S3C64XX_SPI_INT_RX_OVERRUN_EN		(1<<5)
82#define S3C64XX_SPI_INT_RX_UNDERRUN_EN		(1<<4)
83#define S3C64XX_SPI_INT_TX_OVERRUN_EN		(1<<3)
84#define S3C64XX_SPI_INT_TX_UNDERRUN_EN		(1<<2)
85#define S3C64XX_SPI_INT_RX_FIFORDY_EN		(1<<1)
86#define S3C64XX_SPI_INT_TX_FIFORDY_EN		(1<<0)
87
88#define S3C64XX_SPI_ST_RX_OVERRUN_ERR		(1<<5)
89#define S3C64XX_SPI_ST_RX_UNDERRUN_ERR	(1<<4)
90#define S3C64XX_SPI_ST_TX_OVERRUN_ERR		(1<<3)
91#define S3C64XX_SPI_ST_TX_UNDERRUN_ERR	(1<<2)
92#define S3C64XX_SPI_ST_RX_FIFORDY		(1<<1)
93#define S3C64XX_SPI_ST_TX_FIFORDY		(1<<0)
94
95#define S3C64XX_SPI_PACKET_CNT_EN		(1<<16)
96
97#define S3C64XX_SPI_PND_TX_UNDERRUN_CLR		(1<<4)
98#define S3C64XX_SPI_PND_TX_OVERRUN_CLR		(1<<3)
99#define S3C64XX_SPI_PND_RX_UNDERRUN_CLR		(1<<2)
100#define S3C64XX_SPI_PND_RX_OVERRUN_CLR		(1<<1)
101#define S3C64XX_SPI_PND_TRAILING_CLR		(1<<0)
102
103#define S3C64XX_SPI_SWAP_RX_HALF_WORD		(1<<7)
104#define S3C64XX_SPI_SWAP_RX_BYTE		(1<<6)
105#define S3C64XX_SPI_SWAP_RX_BIT			(1<<5)
106#define S3C64XX_SPI_SWAP_RX_EN			(1<<4)
107#define S3C64XX_SPI_SWAP_TX_HALF_WORD		(1<<3)
108#define S3C64XX_SPI_SWAP_TX_BYTE		(1<<2)
109#define S3C64XX_SPI_SWAP_TX_BIT			(1<<1)
110#define S3C64XX_SPI_SWAP_TX_EN			(1<<0)
111
112#define S3C64XX_SPI_FBCLK_MSK		(3<<0)
113
114#define FIFO_LVL_MASK(i) ((i)->port_conf->fifo_lvl_mask[i->port_id])
115#define S3C64XX_SPI_ST_TX_DONE(v, i) (((v) & \
116				(1 << (i)->port_conf->tx_st_done)) ? 1 : 0)
117#define TX_FIFO_LVL(v, i) (((v) >> 6) & FIFO_LVL_MASK(i))
118#define RX_FIFO_LVL(v, i) (((v) >> (i)->port_conf->rx_lvl_offset) & \
119					FIFO_LVL_MASK(i))
120
121#define S3C64XX_SPI_MAX_TRAILCNT	0x3ff
122#define S3C64XX_SPI_TRAILCNT_OFF	19
123
124#define S3C64XX_SPI_TRAILCNT		S3C64XX_SPI_MAX_TRAILCNT
125
126#define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
127#define is_polling(x)	(x->port_conf->quirks & S3C64XX_SPI_QUIRK_POLL)
128
129#define RXBUSY    (1<<2)
130#define TXBUSY    (1<<3)
131
132struct s3c64xx_spi_dma_data {
133	struct dma_chan *ch;
134	enum dma_transfer_direction direction;
135	unsigned int dmach;
136};
137
138/**
139 * struct s3c64xx_spi_info - SPI Controller hardware info
140 * @fifo_lvl_mask: Bit-mask for {TX|RX}_FIFO_LVL bits in SPI_STATUS register.
141 * @rx_lvl_offset: Bit offset of RX_FIFO_LVL bits in SPI_STATUS regiter.
142 * @tx_st_done: Bit offset of TX_DONE bit in SPI_STATUS regiter.
143 * @high_speed: True, if the controller supports HIGH_SPEED_EN bit.
144 * @clk_from_cmu: True, if the controller does not include a clock mux and
145 *	prescaler unit.
146 *
147 * The Samsung s3c64xx SPI controller are used on various Samsung SoC's but
148 * differ in some aspects such as the size of the fifo and spi bus clock
149 * setup. Such differences are specified to the driver using this structure
150 * which is provided as driver data to the driver.
151 */
152struct s3c64xx_spi_port_config {
153	int	fifo_lvl_mask[MAX_SPI_PORTS];
154	int	rx_lvl_offset;
155	int	tx_st_done;
156	int	quirks;
157	bool	high_speed;
158	bool	clk_from_cmu;
159};
160
161/**
162 * struct s3c64xx_spi_driver_data - Runtime info holder for SPI driver.
163 * @clk: Pointer to the spi clock.
164 * @src_clk: Pointer to the clock used to generate SPI signals.
165 * @master: Pointer to the SPI Protocol master.
166 * @cntrlr_info: Platform specific data for the controller this driver manages.
167 * @tgl_spi: Pointer to the last CS left untoggled by the cs_change hint.
168 * @lock: Controller specific lock.
169 * @state: Set of FLAGS to indicate status.
170 * @rx_dmach: Controller's DMA channel for Rx.
171 * @tx_dmach: Controller's DMA channel for Tx.
172 * @sfr_start: BUS address of SPI controller regs.
173 * @regs: Pointer to ioremap'ed controller registers.
174 * @irq: interrupt
175 * @xfer_completion: To indicate completion of xfer task.
176 * @cur_mode: Stores the active configuration of the controller.
177 * @cur_bpw: Stores the active bits per word settings.
178 * @cur_speed: Stores the active xfer clock speed.
179 */
180struct s3c64xx_spi_driver_data {
181	void __iomem                    *regs;
182	struct clk                      *clk;
183	struct clk                      *src_clk;
184	struct platform_device          *pdev;
185	struct spi_master               *master;
186	struct s3c64xx_spi_info  *cntrlr_info;
187	struct spi_device               *tgl_spi;
188	spinlock_t                      lock;
189	unsigned long                   sfr_start;
190	struct completion               xfer_completion;
191	unsigned                        state;
192	unsigned                        cur_mode, cur_bpw;
193	unsigned                        cur_speed;
194	struct s3c64xx_spi_dma_data	rx_dma;
195	struct s3c64xx_spi_dma_data	tx_dma;
196	struct s3c64xx_spi_port_config	*port_conf;
197	unsigned int			port_id;
198};
199
200static void flush_fifo(struct s3c64xx_spi_driver_data *sdd)
201{
202	void __iomem *regs = sdd->regs;
203	unsigned long loops;
204	u32 val;
205
206	writel(0, regs + S3C64XX_SPI_PACKET_CNT);
207
208	val = readl(regs + S3C64XX_SPI_CH_CFG);
209	val &= ~(S3C64XX_SPI_CH_RXCH_ON | S3C64XX_SPI_CH_TXCH_ON);
210	writel(val, regs + S3C64XX_SPI_CH_CFG);
211
212	val = readl(regs + S3C64XX_SPI_CH_CFG);
213	val |= S3C64XX_SPI_CH_SW_RST;
214	val &= ~S3C64XX_SPI_CH_HS_EN;
215	writel(val, regs + S3C64XX_SPI_CH_CFG);
216
217	/* Flush TxFIFO*/
218	loops = msecs_to_loops(1);
219	do {
220		val = readl(regs + S3C64XX_SPI_STATUS);
221	} while (TX_FIFO_LVL(val, sdd) && loops--);
222
223	if (loops == 0)
224		dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n");
225
226	/* Flush RxFIFO*/
227	loops = msecs_to_loops(1);
228	do {
229		val = readl(regs + S3C64XX_SPI_STATUS);
230		if (RX_FIFO_LVL(val, sdd))
231			readl(regs + S3C64XX_SPI_RX_DATA);
232		else
233			break;
234	} while (loops--);
235
236	if (loops == 0)
237		dev_warn(&sdd->pdev->dev, "Timed out flushing RX FIFO\n");
238
239	val = readl(regs + S3C64XX_SPI_CH_CFG);
240	val &= ~S3C64XX_SPI_CH_SW_RST;
241	writel(val, regs + S3C64XX_SPI_CH_CFG);
242
243	val = readl(regs + S3C64XX_SPI_MODE_CFG);
244	val &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
245	writel(val, regs + S3C64XX_SPI_MODE_CFG);
246}
247
248static void s3c64xx_spi_dmacb(void *data)
249{
250	struct s3c64xx_spi_driver_data *sdd;
251	struct s3c64xx_spi_dma_data *dma = data;
252	unsigned long flags;
253
254	if (dma->direction == DMA_DEV_TO_MEM)
255		sdd = container_of(data,
256			struct s3c64xx_spi_driver_data, rx_dma);
257	else
258		sdd = container_of(data,
259			struct s3c64xx_spi_driver_data, tx_dma);
260
261	spin_lock_irqsave(&sdd->lock, flags);
262
263	if (dma->direction == DMA_DEV_TO_MEM) {
264		sdd->state &= ~RXBUSY;
265		if (!(sdd->state & TXBUSY))
266			complete(&sdd->xfer_completion);
267	} else {
268		sdd->state &= ~TXBUSY;
269		if (!(sdd->state & RXBUSY))
270			complete(&sdd->xfer_completion);
271	}
272
273	spin_unlock_irqrestore(&sdd->lock, flags);
274}
275
276static void prepare_dma(struct s3c64xx_spi_dma_data *dma,
277			struct sg_table *sgt)
278{
279	struct s3c64xx_spi_driver_data *sdd;
280	struct dma_slave_config config;
281	struct dma_async_tx_descriptor *desc;
282
283	memset(&config, 0, sizeof(config));
284
285	if (dma->direction == DMA_DEV_TO_MEM) {
286		sdd = container_of((void *)dma,
287			struct s3c64xx_spi_driver_data, rx_dma);
288		config.direction = dma->direction;
289		config.src_addr = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
290		config.src_addr_width = sdd->cur_bpw / 8;
291		config.src_maxburst = 1;
292		dmaengine_slave_config(dma->ch, &config);
293	} else {
294		sdd = container_of((void *)dma,
295			struct s3c64xx_spi_driver_data, tx_dma);
296		config.direction = dma->direction;
297		config.dst_addr = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
298		config.dst_addr_width = sdd->cur_bpw / 8;
299		config.dst_maxburst = 1;
300		dmaengine_slave_config(dma->ch, &config);
301	}
302
303	desc = dmaengine_prep_slave_sg(dma->ch, sgt->sgl, sgt->nents,
304				       dma->direction, DMA_PREP_INTERRUPT);
305
306	desc->callback = s3c64xx_spi_dmacb;
307	desc->callback_param = dma;
308
309	dmaengine_submit(desc);
310	dma_async_issue_pending(dma->ch);
311}
312
313static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
314{
315	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
316	dma_filter_fn filter = sdd->cntrlr_info->filter;
317	struct device *dev = &sdd->pdev->dev;
318	dma_cap_mask_t mask;
319	int ret;
320
321	if (!is_polling(sdd)) {
322		dma_cap_zero(mask);
323		dma_cap_set(DMA_SLAVE, mask);
324
325		/* Acquire DMA channels */
326		sdd->rx_dma.ch = dma_request_slave_channel_compat(mask, filter,
327				   (void *)(long)sdd->rx_dma.dmach, dev, "rx");
328		if (!sdd->rx_dma.ch) {
329			dev_err(dev, "Failed to get RX DMA channel\n");
330			ret = -EBUSY;
331			goto out;
332		}
333		spi->dma_rx = sdd->rx_dma.ch;
334
335		sdd->tx_dma.ch = dma_request_slave_channel_compat(mask, filter,
336				   (void *)(long)sdd->tx_dma.dmach, dev, "tx");
337		if (!sdd->tx_dma.ch) {
338			dev_err(dev, "Failed to get TX DMA channel\n");
339			ret = -EBUSY;
340			goto out_rx;
341		}
342		spi->dma_tx = sdd->tx_dma.ch;
343	}
344
345	return 0;
346
347out_rx:
348	dma_release_channel(sdd->rx_dma.ch);
349out:
350	return ret;
351}
352
353static int s3c64xx_spi_unprepare_transfer(struct spi_master *spi)
354{
355	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
356
357	/* Free DMA channels */
358	if (!is_polling(sdd)) {
359		dma_release_channel(sdd->rx_dma.ch);
360		dma_release_channel(sdd->tx_dma.ch);
361	}
362
363	return 0;
364}
365
366static bool s3c64xx_spi_can_dma(struct spi_master *master,
367				struct spi_device *spi,
368				struct spi_transfer *xfer)
369{
370	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
371
372	return xfer->len > (FIFO_LVL_MASK(sdd) >> 1) + 1;
373}
374
375static void enable_datapath(struct s3c64xx_spi_driver_data *sdd,
376				struct spi_device *spi,
377				struct spi_transfer *xfer, int dma_mode)
378{
379	void __iomem *regs = sdd->regs;
380	u32 modecfg, chcfg;
381
382	modecfg = readl(regs + S3C64XX_SPI_MODE_CFG);
383	modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
384
385	chcfg = readl(regs + S3C64XX_SPI_CH_CFG);
386	chcfg &= ~S3C64XX_SPI_CH_TXCH_ON;
387
388	if (dma_mode) {
389		chcfg &= ~S3C64XX_SPI_CH_RXCH_ON;
390	} else {
391		/* Always shift in data in FIFO, even if xfer is Tx only,
392		 * this helps setting PCKT_CNT value for generating clocks
393		 * as exactly needed.
394		 */
395		chcfg |= S3C64XX_SPI_CH_RXCH_ON;
396		writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
397					| S3C64XX_SPI_PACKET_CNT_EN,
398					regs + S3C64XX_SPI_PACKET_CNT);
399	}
400
401	if (xfer->tx_buf != NULL) {
402		sdd->state |= TXBUSY;
403		chcfg |= S3C64XX_SPI_CH_TXCH_ON;
404		if (dma_mode) {
405			modecfg |= S3C64XX_SPI_MODE_TXDMA_ON;
406			prepare_dma(&sdd->tx_dma, &xfer->tx_sg);
407		} else {
408			switch (sdd->cur_bpw) {
409			case 32:
410				iowrite32_rep(regs + S3C64XX_SPI_TX_DATA,
411					xfer->tx_buf, xfer->len / 4);
412				break;
413			case 16:
414				iowrite16_rep(regs + S3C64XX_SPI_TX_DATA,
415					xfer->tx_buf, xfer->len / 2);
416				break;
417			default:
418				iowrite8_rep(regs + S3C64XX_SPI_TX_DATA,
419					xfer->tx_buf, xfer->len);
420				break;
421			}
422		}
423	}
424
425	if (xfer->rx_buf != NULL) {
426		sdd->state |= RXBUSY;
427
428		if (sdd->port_conf->high_speed && sdd->cur_speed >= 30000000UL
429					&& !(sdd->cur_mode & SPI_CPHA))
430			chcfg |= S3C64XX_SPI_CH_HS_EN;
431
432		if (dma_mode) {
433			modecfg |= S3C64XX_SPI_MODE_RXDMA_ON;
434			chcfg |= S3C64XX_SPI_CH_RXCH_ON;
435			writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
436					| S3C64XX_SPI_PACKET_CNT_EN,
437					regs + S3C64XX_SPI_PACKET_CNT);
438			prepare_dma(&sdd->rx_dma, &xfer->rx_sg);
439		}
440	}
441
442	writel(modecfg, regs + S3C64XX_SPI_MODE_CFG);
443	writel(chcfg, regs + S3C64XX_SPI_CH_CFG);
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 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 += 10; /* some tolerance */
478
479	val = msecs_to_jiffies(ms) + 10;
480	val = wait_for_completion_timeout(&sdd->xfer_completion, val);
481
482	/*
483	 * If the previous xfer was completed within timeout, then
484	 * proceed further else return -EIO.
485	 * DmaTx returns after simply writing data in the FIFO,
486	 * w/o waiting for real transmission on the bus to finish.
487	 * DmaRx returns only after Dma read data from FIFO which
488	 * needs bus transmission to finish, so we don't worry if
489	 * Xfer involved Rx(with or without Tx).
490	 */
491	if (val && !xfer->rx_buf) {
492		val = msecs_to_loops(10);
493		status = readl(regs + S3C64XX_SPI_STATUS);
494		while ((TX_FIFO_LVL(status, sdd)
495			|| !S3C64XX_SPI_ST_TX_DONE(status, sdd))
496		       && --val) {
497			cpu_relax();
498			status = readl(regs + S3C64XX_SPI_STATUS);
499		}
500
501	}
502
503	/* If timed out while checking rx/tx status return error */
504	if (!val)
505		return -EIO;
506
507	return 0;
508}
509
510static int wait_for_pio(struct s3c64xx_spi_driver_data *sdd,
511			struct spi_transfer *xfer)
512{
513	void __iomem *regs = sdd->regs;
514	unsigned long val;
515	u32 status;
516	int loops;
517	u32 cpy_len;
518	u8 *buf;
519	int ms;
520
521	/* millisecs to xfer 'len' bytes @ 'cur_speed' */
522	ms = xfer->len * 8 * 1000 / sdd->cur_speed;
523	ms += 10; /* some tolerance */
524
525	val = msecs_to_loops(ms);
526	do {
527		status = readl(regs + S3C64XX_SPI_STATUS);
528	} while (RX_FIFO_LVL(status, sdd) < xfer->len && --val);
529
530
531	/* If it was only Tx */
532	if (!xfer->rx_buf) {
533		sdd->state &= ~TXBUSY;
534		return 0;
535	}
536
537	/*
538	 * If the receive length is bigger than the controller fifo
539	 * size, calculate the loops and read the fifo as many times.
540	 * loops = length / max fifo size (calculated by using the
541	 * fifo mask).
542	 * For any size less than the fifo size the below code is
543	 * executed atleast once.
544	 */
545	loops = xfer->len / ((FIFO_LVL_MASK(sdd) >> 1) + 1);
546	buf = xfer->rx_buf;
547	do {
548		/* wait for data to be received in the fifo */
549		cpy_len = s3c64xx_spi_wait_for_timeout(sdd,
550						       (loops ? ms : 0));
551
552		switch (sdd->cur_bpw) {
553		case 32:
554			ioread32_rep(regs + S3C64XX_SPI_RX_DATA,
555				     buf, cpy_len / 4);
556			break;
557		case 16:
558			ioread16_rep(regs + S3C64XX_SPI_RX_DATA,
559				     buf, cpy_len / 2);
560			break;
561		default:
562			ioread8_rep(regs + S3C64XX_SPI_RX_DATA,
563				    buf, cpy_len);
564			break;
565		}
566
567		buf = buf + cpy_len;
568	} while (loops--);
569	sdd->state &= ~RXBUSY;
570
571	return 0;
572}
573
574static void s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
575{
576	void __iomem *regs = sdd->regs;
577	u32 val;
578
579	/* Disable Clock */
580	if (sdd->port_conf->clk_from_cmu) {
581		clk_disable_unprepare(sdd->src_clk);
582	} else {
583		val = readl(regs + S3C64XX_SPI_CLK_CFG);
584		val &= ~S3C64XX_SPI_ENCLK_ENABLE;
585		writel(val, regs + S3C64XX_SPI_CLK_CFG);
586	}
587
588	/* Set Polarity and Phase */
589	val = readl(regs + S3C64XX_SPI_CH_CFG);
590	val &= ~(S3C64XX_SPI_CH_SLAVE |
591			S3C64XX_SPI_CPOL_L |
592			S3C64XX_SPI_CPHA_B);
593
594	if (sdd->cur_mode & SPI_CPOL)
595		val |= S3C64XX_SPI_CPOL_L;
596
597	if (sdd->cur_mode & SPI_CPHA)
598		val |= S3C64XX_SPI_CPHA_B;
599
600	writel(val, regs + S3C64XX_SPI_CH_CFG);
601
602	/* Set Channel & DMA Mode */
603	val = readl(regs + S3C64XX_SPI_MODE_CFG);
604	val &= ~(S3C64XX_SPI_MODE_BUS_TSZ_MASK
605			| S3C64XX_SPI_MODE_CH_TSZ_MASK);
606
607	switch (sdd->cur_bpw) {
608	case 32:
609		val |= S3C64XX_SPI_MODE_BUS_TSZ_WORD;
610		val |= S3C64XX_SPI_MODE_CH_TSZ_WORD;
611		break;
612	case 16:
613		val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD;
614		val |= S3C64XX_SPI_MODE_CH_TSZ_HALFWORD;
615		break;
616	default:
617		val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE;
618		val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE;
619		break;
620	}
621
622	writel(val, regs + S3C64XX_SPI_MODE_CFG);
623
624	if (sdd->port_conf->clk_from_cmu) {
625		/* Configure Clock */
626		/* There is half-multiplier before the SPI */
627		clk_set_rate(sdd->src_clk, sdd->cur_speed * 2);
628		/* Enable Clock */
629		clk_prepare_enable(sdd->src_clk);
630	} else {
631		/* Configure Clock */
632		val = readl(regs + S3C64XX_SPI_CLK_CFG);
633		val &= ~S3C64XX_SPI_PSR_MASK;
634		val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / 2 - 1)
635				& S3C64XX_SPI_PSR_MASK);
636		writel(val, regs + S3C64XX_SPI_CLK_CFG);
637
638		/* Enable Clock */
639		val = readl(regs + S3C64XX_SPI_CLK_CFG);
640		val |= S3C64XX_SPI_ENCLK_ENABLE;
641		writel(val, regs + S3C64XX_SPI_CLK_CFG);
642	}
643}
644
645#define XFER_DMAADDR_INVALID DMA_BIT_MASK(32)
646
647static int s3c64xx_spi_prepare_message(struct spi_master *master,
648				       struct spi_message *msg)
649{
650	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
651	struct spi_device *spi = msg->spi;
652	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
653
654	/* If Master's(controller) state differs from that needed by Slave */
655	if (sdd->cur_speed != spi->max_speed_hz
656			|| sdd->cur_mode != spi->mode
657			|| sdd->cur_bpw != spi->bits_per_word) {
658		sdd->cur_bpw = spi->bits_per_word;
659		sdd->cur_speed = spi->max_speed_hz;
660		sdd->cur_mode = spi->mode;
661		s3c64xx_spi_config(sdd);
662	}
663
664	/* Configure feedback delay */
665	writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK);
666
667	return 0;
668}
669
670static int s3c64xx_spi_transfer_one(struct spi_master *master,
671				    struct spi_device *spi,
672				    struct spi_transfer *xfer)
673{
674	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
675	int status;
676	u32 speed;
677	u8 bpw;
678	unsigned long flags;
679	int use_dma;
680
681	reinit_completion(&sdd->xfer_completion);
682
683	/* Only BPW and Speed may change across transfers */
684	bpw = xfer->bits_per_word;
685	speed = xfer->speed_hz ? : spi->max_speed_hz;
686
687	if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) {
688		sdd->cur_bpw = bpw;
689		sdd->cur_speed = speed;
690		s3c64xx_spi_config(sdd);
691	}
692
693	/* Polling method for xfers not bigger than FIFO capacity */
694	use_dma = 0;
695	if (!is_polling(sdd) &&
696	    (sdd->rx_dma.ch && sdd->tx_dma.ch &&
697	     (xfer->len > ((FIFO_LVL_MASK(sdd) >> 1) + 1))))
698		use_dma = 1;
699
700	spin_lock_irqsave(&sdd->lock, flags);
701
702	/* Pending only which is to be done */
703	sdd->state &= ~RXBUSY;
704	sdd->state &= ~TXBUSY;
705
706	enable_datapath(sdd, spi, xfer, use_dma);
707
708	/* Start the signals */
709	if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
710		writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
711	else
712		writel(readl(sdd->regs + S3C64XX_SPI_SLAVE_SEL)
713			| S3C64XX_SPI_SLAVE_AUTO | S3C64XX_SPI_SLAVE_NSC_CNT_2,
714			sdd->regs + S3C64XX_SPI_SLAVE_SEL);
715
716	spin_unlock_irqrestore(&sdd->lock, flags);
717
718	if (use_dma)
719		status = wait_for_dma(sdd, xfer);
720	else
721		status = wait_for_pio(sdd, xfer);
722
723	if (status) {
724		dev_err(&spi->dev, "I/O Error: rx-%d tx-%d res:rx-%c tx-%c len-%d\n",
725			xfer->rx_buf ? 1 : 0, xfer->tx_buf ? 1 : 0,
726			(sdd->state & RXBUSY) ? 'f' : 'p',
727			(sdd->state & TXBUSY) ? 'f' : 'p',
728			xfer->len);
729
730		if (use_dma) {
731			if (xfer->tx_buf != NULL
732			    && (sdd->state & TXBUSY))
733				dmaengine_terminate_all(sdd->tx_dma.ch);
734			if (xfer->rx_buf != NULL
735			    && (sdd->state & RXBUSY))
736				dmaengine_terminate_all(sdd->rx_dma.ch);
737		}
738	} else {
739		flush_fifo(sdd);
740	}
741
742	return status;
743}
744
745static struct s3c64xx_spi_csinfo *s3c64xx_get_slave_ctrldata(
746				struct spi_device *spi)
747{
748	struct s3c64xx_spi_csinfo *cs;
749	struct device_node *slave_np, *data_np = NULL;
750	u32 fb_delay = 0;
751
752	slave_np = spi->dev.of_node;
753	if (!slave_np) {
754		dev_err(&spi->dev, "device node not found\n");
755		return ERR_PTR(-EINVAL);
756	}
757
758	data_np = of_get_child_by_name(slave_np, "controller-data");
759	if (!data_np) {
760		dev_err(&spi->dev, "child node 'controller-data' not found\n");
761		return ERR_PTR(-EINVAL);
762	}
763
764	cs = kzalloc(sizeof(*cs), GFP_KERNEL);
765	if (!cs) {
766		of_node_put(data_np);
767		return ERR_PTR(-ENOMEM);
768	}
769
770	of_property_read_u32(data_np, "samsung,spi-feedback-delay", &fb_delay);
771	cs->fb_delay = fb_delay;
772	of_node_put(data_np);
773	return cs;
774}
775
776/*
777 * Here we only check the validity of requested configuration
778 * and save the configuration in a local data-structure.
779 * The controller is actually configured only just before we
780 * get a message to transfer.
781 */
782static int s3c64xx_spi_setup(struct spi_device *spi)
783{
784	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
785	struct s3c64xx_spi_driver_data *sdd;
786	struct s3c64xx_spi_info *sci;
787	int err;
788
789	sdd = spi_master_get_devdata(spi->master);
790	if (spi->dev.of_node) {
791		cs = s3c64xx_get_slave_ctrldata(spi);
792		spi->controller_data = cs;
793	} else if (cs) {
794		/* On non-DT platforms the SPI core will set spi->cs_gpio
795		 * to -ENOENT. The GPIO pin used to drive the chip select
796		 * is defined by using platform data so spi->cs_gpio value
797		 * has to be override to have the proper GPIO pin number.
798		 */
799		spi->cs_gpio = cs->line;
800	}
801
802	if (IS_ERR_OR_NULL(cs)) {
803		dev_err(&spi->dev, "No CS for SPI(%d)\n", spi->chip_select);
804		return -ENODEV;
805	}
806
807	if (!spi_get_ctldata(spi)) {
808		if (gpio_is_valid(spi->cs_gpio)) {
809			err = gpio_request_one(spi->cs_gpio, GPIOF_OUT_INIT_HIGH,
810					       dev_name(&spi->dev));
811			if (err) {
812				dev_err(&spi->dev,
813					"Failed to get /CS gpio [%d]: %d\n",
814					spi->cs_gpio, err);
815				goto err_gpio_req;
816			}
817		}
818
819		spi_set_ctldata(spi, cs);
820	}
821
822	sci = sdd->cntrlr_info;
823
824	pm_runtime_get_sync(&sdd->pdev->dev);
825
826	/* Check if we can provide the requested rate */
827	if (!sdd->port_conf->clk_from_cmu) {
828		u32 psr, speed;
829
830		/* Max possible */
831		speed = clk_get_rate(sdd->src_clk) / 2 / (0 + 1);
832
833		if (spi->max_speed_hz > speed)
834			spi->max_speed_hz = speed;
835
836		psr = clk_get_rate(sdd->src_clk) / 2 / spi->max_speed_hz - 1;
837		psr &= S3C64XX_SPI_PSR_MASK;
838		if (psr == S3C64XX_SPI_PSR_MASK)
839			psr--;
840
841		speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
842		if (spi->max_speed_hz < speed) {
843			if (psr+1 < S3C64XX_SPI_PSR_MASK) {
844				psr++;
845			} else {
846				err = -EINVAL;
847				goto setup_exit;
848			}
849		}
850
851		speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
852		if (spi->max_speed_hz >= speed) {
853			spi->max_speed_hz = speed;
854		} else {
855			dev_err(&spi->dev, "Can't set %dHz transfer speed\n",
856				spi->max_speed_hz);
857			err = -EINVAL;
858			goto setup_exit;
859		}
860	}
861
862	pm_runtime_put(&sdd->pdev->dev);
863	if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
864		writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
865	return 0;
866
867setup_exit:
868	pm_runtime_put(&sdd->pdev->dev);
869	/* setup() returns with device de-selected */
870	if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
871		writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
872
873	if (gpio_is_valid(spi->cs_gpio))
874		gpio_free(spi->cs_gpio);
875	spi_set_ctldata(spi, NULL);
876
877err_gpio_req:
878	if (spi->dev.of_node)
879		kfree(cs);
880
881	return err;
882}
883
884static void s3c64xx_spi_cleanup(struct spi_device *spi)
885{
886	struct s3c64xx_spi_csinfo *cs = spi_get_ctldata(spi);
887
888	if (gpio_is_valid(spi->cs_gpio)) {
889		gpio_free(spi->cs_gpio);
890		if (spi->dev.of_node)
891			kfree(cs);
892		else {
893			/* On non-DT platforms, the SPI core sets
894			 * spi->cs_gpio to -ENOENT and .setup()
895			 * overrides it with the GPIO pin value
896			 * passed using platform data.
897			 */
898			spi->cs_gpio = -ENOENT;
899		}
900	}
901
902	spi_set_ctldata(spi, NULL);
903}
904
905static irqreturn_t s3c64xx_spi_irq(int irq, void *data)
906{
907	struct s3c64xx_spi_driver_data *sdd = data;
908	struct spi_master *spi = sdd->master;
909	unsigned int val, clr = 0;
910
911	val = readl(sdd->regs + S3C64XX_SPI_STATUS);
912
913	if (val & S3C64XX_SPI_ST_RX_OVERRUN_ERR) {
914		clr = S3C64XX_SPI_PND_RX_OVERRUN_CLR;
915		dev_err(&spi->dev, "RX overrun\n");
916	}
917	if (val & S3C64XX_SPI_ST_RX_UNDERRUN_ERR) {
918		clr |= S3C64XX_SPI_PND_RX_UNDERRUN_CLR;
919		dev_err(&spi->dev, "RX underrun\n");
920	}
921	if (val & S3C64XX_SPI_ST_TX_OVERRUN_ERR) {
922		clr |= S3C64XX_SPI_PND_TX_OVERRUN_CLR;
923		dev_err(&spi->dev, "TX overrun\n");
924	}
925	if (val & S3C64XX_SPI_ST_TX_UNDERRUN_ERR) {
926		clr |= S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
927		dev_err(&spi->dev, "TX underrun\n");
928	}
929
930	/* Clear the pending irq by setting and then clearing it */
931	writel(clr, sdd->regs + S3C64XX_SPI_PENDING_CLR);
932	writel(0, sdd->regs + S3C64XX_SPI_PENDING_CLR);
933
934	return IRQ_HANDLED;
935}
936
937static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd, int channel)
938{
939	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
940	void __iomem *regs = sdd->regs;
941	unsigned int val;
942
943	sdd->cur_speed = 0;
944
945	if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
946		writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
947
948	/* Disable Interrupts - we use Polling if not DMA mode */
949	writel(0, regs + S3C64XX_SPI_INT_EN);
950
951	if (!sdd->port_conf->clk_from_cmu)
952		writel(sci->src_clk_nr << S3C64XX_SPI_CLKSEL_SRCSHFT,
953				regs + S3C64XX_SPI_CLK_CFG);
954	writel(0, regs + S3C64XX_SPI_MODE_CFG);
955	writel(0, regs + S3C64XX_SPI_PACKET_CNT);
956
957	/* Clear any irq pending bits, should set and clear the bits */
958	val = S3C64XX_SPI_PND_RX_OVERRUN_CLR |
959		S3C64XX_SPI_PND_RX_UNDERRUN_CLR |
960		S3C64XX_SPI_PND_TX_OVERRUN_CLR |
961		S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
962	writel(val, regs + S3C64XX_SPI_PENDING_CLR);
963	writel(0, regs + S3C64XX_SPI_PENDING_CLR);
964
965	writel(0, regs + S3C64XX_SPI_SWAP_CFG);
966
967	val = readl(regs + S3C64XX_SPI_MODE_CFG);
968	val &= ~S3C64XX_SPI_MODE_4BURST;
969	val &= ~(S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
970	val |= (S3C64XX_SPI_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
971	writel(val, regs + S3C64XX_SPI_MODE_CFG);
972
973	flush_fifo(sdd);
974}
975
976#ifdef CONFIG_OF
977static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
978{
979	struct s3c64xx_spi_info *sci;
980	u32 temp;
981
982	sci = devm_kzalloc(dev, sizeof(*sci), GFP_KERNEL);
983	if (!sci)
984		return ERR_PTR(-ENOMEM);
985
986	if (of_property_read_u32(dev->of_node, "samsung,spi-src-clk", &temp)) {
987		dev_warn(dev, "spi bus clock parent not specified, using clock at index 0 as parent\n");
988		sci->src_clk_nr = 0;
989	} else {
990		sci->src_clk_nr = temp;
991	}
992
993	if (of_property_read_u32(dev->of_node, "num-cs", &temp)) {
994		dev_warn(dev, "number of chip select lines not specified, assuming 1 chip select line\n");
995		sci->num_cs = 1;
996	} else {
997		sci->num_cs = temp;
998	}
999
1000	return sci;
1001}
1002#else
1003static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
1004{
1005	return dev_get_platdata(dev);
1006}
1007#endif
1008
1009static const struct of_device_id s3c64xx_spi_dt_match[];
1010
1011static inline struct s3c64xx_spi_port_config *s3c64xx_spi_get_port_config(
1012						struct platform_device *pdev)
1013{
1014#ifdef CONFIG_OF
1015	if (pdev->dev.of_node) {
1016		const struct of_device_id *match;
1017		match = of_match_node(s3c64xx_spi_dt_match, pdev->dev.of_node);
1018		return (struct s3c64xx_spi_port_config *)match->data;
1019	}
1020#endif
1021	return (struct s3c64xx_spi_port_config *)
1022			 platform_get_device_id(pdev)->driver_data;
1023}
1024
1025static int s3c64xx_spi_probe(struct platform_device *pdev)
1026{
1027	struct resource	*mem_res;
1028	struct resource	*res;
1029	struct s3c64xx_spi_driver_data *sdd;
1030	struct s3c64xx_spi_info *sci = dev_get_platdata(&pdev->dev);
1031	struct spi_master *master;
1032	int ret, irq;
1033	char clk_name[16];
1034
1035	if (!sci && pdev->dev.of_node) {
1036		sci = s3c64xx_spi_parse_dt(&pdev->dev);
1037		if (IS_ERR(sci))
1038			return PTR_ERR(sci);
1039	}
1040
1041	if (!sci) {
1042		dev_err(&pdev->dev, "platform_data missing!\n");
1043		return -ENODEV;
1044	}
1045
1046	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1047	if (mem_res == NULL) {
1048		dev_err(&pdev->dev, "Unable to get SPI MEM resource\n");
1049		return -ENXIO;
1050	}
1051
1052	irq = platform_get_irq(pdev, 0);
1053	if (irq < 0) {
1054		dev_warn(&pdev->dev, "Failed to get IRQ: %d\n", irq);
1055		return irq;
1056	}
1057
1058	master = spi_alloc_master(&pdev->dev,
1059				sizeof(struct s3c64xx_spi_driver_data));
1060	if (master == NULL) {
1061		dev_err(&pdev->dev, "Unable to allocate SPI Master\n");
1062		return -ENOMEM;
1063	}
1064
1065	platform_set_drvdata(pdev, master);
1066
1067	sdd = spi_master_get_devdata(master);
1068	sdd->port_conf = s3c64xx_spi_get_port_config(pdev);
1069	sdd->master = master;
1070	sdd->cntrlr_info = sci;
1071	sdd->pdev = pdev;
1072	sdd->sfr_start = mem_res->start;
1073	if (pdev->dev.of_node) {
1074		ret = of_alias_get_id(pdev->dev.of_node, "spi");
1075		if (ret < 0) {
1076			dev_err(&pdev->dev, "failed to get alias id, errno %d\n",
1077				ret);
1078			goto err0;
1079		}
1080		sdd->port_id = ret;
1081	} else {
1082		sdd->port_id = pdev->id;
1083	}
1084
1085	sdd->cur_bpw = 8;
1086
1087	if (!sdd->pdev->dev.of_node) {
1088		res = platform_get_resource(pdev, IORESOURCE_DMA,  0);
1089		if (!res) {
1090			dev_warn(&pdev->dev, "Unable to get SPI tx dma resource. Switching to poll mode\n");
1091			sdd->port_conf->quirks = S3C64XX_SPI_QUIRK_POLL;
1092		} else
1093			sdd->tx_dma.dmach = res->start;
1094
1095		res = platform_get_resource(pdev, IORESOURCE_DMA,  1);
1096		if (!res) {
1097			dev_warn(&pdev->dev, "Unable to get SPI rx dma resource. Switching to poll mode\n");
1098			sdd->port_conf->quirks = S3C64XX_SPI_QUIRK_POLL;
1099		} else
1100			sdd->rx_dma.dmach = res->start;
1101	}
1102
1103	sdd->tx_dma.direction = DMA_MEM_TO_DEV;
1104	sdd->rx_dma.direction = DMA_DEV_TO_MEM;
1105
1106	master->dev.of_node = pdev->dev.of_node;
1107	master->bus_num = sdd->port_id;
1108	master->setup = s3c64xx_spi_setup;
1109	master->cleanup = s3c64xx_spi_cleanup;
1110	master->prepare_transfer_hardware = s3c64xx_spi_prepare_transfer;
1111	master->prepare_message = s3c64xx_spi_prepare_message;
1112	master->transfer_one = s3c64xx_spi_transfer_one;
1113	master->unprepare_transfer_hardware = s3c64xx_spi_unprepare_transfer;
1114	master->num_chipselect = sci->num_cs;
1115	master->dma_alignment = 8;
1116	master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) |
1117					SPI_BPW_MASK(8);
1118	/* the spi->mode bits understood by this driver: */
1119	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1120	master->auto_runtime_pm = true;
1121	if (!is_polling(sdd))
1122		master->can_dma = s3c64xx_spi_can_dma;
1123
1124	sdd->regs = devm_ioremap_resource(&pdev->dev, mem_res);
1125	if (IS_ERR(sdd->regs)) {
1126		ret = PTR_ERR(sdd->regs);
1127		goto err0;
1128	}
1129
1130	if (sci->cfg_gpio && sci->cfg_gpio()) {
1131		dev_err(&pdev->dev, "Unable to config gpio\n");
1132		ret = -EBUSY;
1133		goto err0;
1134	}
1135
1136	/* Setup clocks */
1137	sdd->clk = devm_clk_get(&pdev->dev, "spi");
1138	if (IS_ERR(sdd->clk)) {
1139		dev_err(&pdev->dev, "Unable to acquire clock 'spi'\n");
1140		ret = PTR_ERR(sdd->clk);
1141		goto err0;
1142	}
1143
1144	if (clk_prepare_enable(sdd->clk)) {
1145		dev_err(&pdev->dev, "Couldn't enable clock 'spi'\n");
1146		ret = -EBUSY;
1147		goto err0;
1148	}
1149
1150	sprintf(clk_name, "spi_busclk%d", sci->src_clk_nr);
1151	sdd->src_clk = devm_clk_get(&pdev->dev, clk_name);
1152	if (IS_ERR(sdd->src_clk)) {
1153		dev_err(&pdev->dev,
1154			"Unable to acquire clock '%s'\n", clk_name);
1155		ret = PTR_ERR(sdd->src_clk);
1156		goto err2;
1157	}
1158
1159	if (clk_prepare_enable(sdd->src_clk)) {
1160		dev_err(&pdev->dev, "Couldn't enable clock '%s'\n", clk_name);
1161		ret = -EBUSY;
1162		goto err2;
1163	}
1164
1165	/* Setup Deufult Mode */
1166	s3c64xx_spi_hwinit(sdd, sdd->port_id);
1167
1168	spin_lock_init(&sdd->lock);
1169	init_completion(&sdd->xfer_completion);
1170
1171	ret = devm_request_irq(&pdev->dev, irq, s3c64xx_spi_irq, 0,
1172				"spi-s3c64xx", sdd);
1173	if (ret != 0) {
1174		dev_err(&pdev->dev, "Failed to request IRQ %d: %d\n",
1175			irq, ret);
1176		goto err3;
1177	}
1178
1179	writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
1180	       S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
1181	       sdd->regs + S3C64XX_SPI_INT_EN);
1182
1183	pm_runtime_set_active(&pdev->dev);
1184	pm_runtime_enable(&pdev->dev);
1185
1186	ret = devm_spi_register_master(&pdev->dev, master);
1187	if (ret != 0) {
1188		dev_err(&pdev->dev, "cannot register SPI master: %d\n", ret);
1189		goto err3;
1190	}
1191
1192	dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d with %d Slaves attached\n",
1193					sdd->port_id, master->num_chipselect);
1194	dev_dbg(&pdev->dev, "\tIOmem=[%pR]\tDMA=[Rx-%d, Tx-%d]\n",
1195					mem_res,
1196					sdd->rx_dma.dmach, sdd->tx_dma.dmach);
1197
1198	return 0;
1199
1200err3:
1201	clk_disable_unprepare(sdd->src_clk);
1202err2:
1203	clk_disable_unprepare(sdd->clk);
1204err0:
1205	spi_master_put(master);
1206
1207	return ret;
1208}
1209
1210static int s3c64xx_spi_remove(struct platform_device *pdev)
1211{
1212	struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
1213	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1214
1215	pm_runtime_disable(&pdev->dev);
1216
1217	writel(0, sdd->regs + S3C64XX_SPI_INT_EN);
1218
1219	clk_disable_unprepare(sdd->src_clk);
1220
1221	clk_disable_unprepare(sdd->clk);
1222
1223	return 0;
1224}
1225
1226#ifdef CONFIG_PM_SLEEP
1227static int s3c64xx_spi_suspend(struct device *dev)
1228{
1229	struct spi_master *master = dev_get_drvdata(dev);
1230	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1231
1232	int ret = spi_master_suspend(master);
1233	if (ret)
1234		return ret;
1235
1236	if (!pm_runtime_suspended(dev)) {
1237		clk_disable_unprepare(sdd->clk);
1238		clk_disable_unprepare(sdd->src_clk);
1239	}
1240
1241	sdd->cur_speed = 0; /* Output Clock is stopped */
1242
1243	return 0;
1244}
1245
1246static int s3c64xx_spi_resume(struct device *dev)
1247{
1248	struct spi_master *master = dev_get_drvdata(dev);
1249	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1250	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1251
1252	if (sci->cfg_gpio)
1253		sci->cfg_gpio();
1254
1255	if (!pm_runtime_suspended(dev)) {
1256		clk_prepare_enable(sdd->src_clk);
1257		clk_prepare_enable(sdd->clk);
1258	}
1259
1260	s3c64xx_spi_hwinit(sdd, sdd->port_id);
1261
1262	return spi_master_resume(master);
1263}
1264#endif /* CONFIG_PM_SLEEP */
1265
1266#ifdef CONFIG_PM
1267static int s3c64xx_spi_runtime_suspend(struct device *dev)
1268{
1269	struct spi_master *master = dev_get_drvdata(dev);
1270	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1271
1272	clk_disable_unprepare(sdd->clk);
1273	clk_disable_unprepare(sdd->src_clk);
1274
1275	return 0;
1276}
1277
1278static int s3c64xx_spi_runtime_resume(struct device *dev)
1279{
1280	struct spi_master *master = dev_get_drvdata(dev);
1281	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1282	int ret;
1283
1284	ret = clk_prepare_enable(sdd->src_clk);
1285	if (ret != 0)
1286		return ret;
1287
1288	ret = clk_prepare_enable(sdd->clk);
1289	if (ret != 0) {
1290		clk_disable_unprepare(sdd->src_clk);
1291		return ret;
1292	}
1293
1294	return 0;
1295}
1296#endif /* CONFIG_PM */
1297
1298static const struct dev_pm_ops s3c64xx_spi_pm = {
1299	SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume)
1300	SET_RUNTIME_PM_OPS(s3c64xx_spi_runtime_suspend,
1301			   s3c64xx_spi_runtime_resume, NULL)
1302};
1303
1304static struct s3c64xx_spi_port_config s3c2443_spi_port_config = {
1305	.fifo_lvl_mask	= { 0x7f },
1306	.rx_lvl_offset	= 13,
1307	.tx_st_done	= 21,
1308	.high_speed	= true,
1309};
1310
1311static struct s3c64xx_spi_port_config s3c6410_spi_port_config = {
1312	.fifo_lvl_mask	= { 0x7f, 0x7F },
1313	.rx_lvl_offset	= 13,
1314	.tx_st_done	= 21,
1315};
1316
1317static struct s3c64xx_spi_port_config s5pv210_spi_port_config = {
1318	.fifo_lvl_mask	= { 0x1ff, 0x7F },
1319	.rx_lvl_offset	= 15,
1320	.tx_st_done	= 25,
1321	.high_speed	= true,
1322};
1323
1324static struct s3c64xx_spi_port_config exynos4_spi_port_config = {
1325	.fifo_lvl_mask	= { 0x1ff, 0x7F, 0x7F },
1326	.rx_lvl_offset	= 15,
1327	.tx_st_done	= 25,
1328	.high_speed	= true,
1329	.clk_from_cmu	= true,
1330};
1331
1332static struct s3c64xx_spi_port_config exynos5440_spi_port_config = {
1333	.fifo_lvl_mask	= { 0x1ff },
1334	.rx_lvl_offset	= 15,
1335	.tx_st_done	= 25,
1336	.high_speed	= true,
1337	.clk_from_cmu	= true,
1338	.quirks		= S3C64XX_SPI_QUIRK_POLL,
1339};
1340
1341static struct s3c64xx_spi_port_config exynos7_spi_port_config = {
1342	.fifo_lvl_mask	= { 0x1ff, 0x7F, 0x7F, 0x7F, 0x7F, 0x1ff},
1343	.rx_lvl_offset	= 15,
1344	.tx_st_done	= 25,
1345	.high_speed	= true,
1346	.clk_from_cmu	= true,
1347	.quirks		= S3C64XX_SPI_QUIRK_CS_AUTO,
1348};
1349
1350static struct platform_device_id s3c64xx_spi_driver_ids[] = {
1351	{
1352		.name		= "s3c2443-spi",
1353		.driver_data	= (kernel_ulong_t)&s3c2443_spi_port_config,
1354	}, {
1355		.name		= "s3c6410-spi",
1356		.driver_data	= (kernel_ulong_t)&s3c6410_spi_port_config,
1357	}, {
1358		.name		= "s5pv210-spi",
1359		.driver_data	= (kernel_ulong_t)&s5pv210_spi_port_config,
1360	}, {
1361		.name		= "exynos4210-spi",
1362		.driver_data	= (kernel_ulong_t)&exynos4_spi_port_config,
1363	},
1364	{ },
1365};
1366
1367static const struct of_device_id s3c64xx_spi_dt_match[] = {
1368	{ .compatible = "samsung,s3c2443-spi",
1369			.data = (void *)&s3c2443_spi_port_config,
1370	},
1371	{ .compatible = "samsung,s3c6410-spi",
1372			.data = (void *)&s3c6410_spi_port_config,
1373	},
1374	{ .compatible = "samsung,s5pv210-spi",
1375			.data = (void *)&s5pv210_spi_port_config,
1376	},
1377	{ .compatible = "samsung,exynos4210-spi",
1378			.data = (void *)&exynos4_spi_port_config,
1379	},
1380	{ .compatible = "samsung,exynos5440-spi",
1381			.data = (void *)&exynos5440_spi_port_config,
1382	},
1383	{ .compatible = "samsung,exynos7-spi",
1384			.data = (void *)&exynos7_spi_port_config,
1385	},
1386	{ },
1387};
1388MODULE_DEVICE_TABLE(of, s3c64xx_spi_dt_match);
1389
1390static struct platform_driver s3c64xx_spi_driver = {
1391	.driver = {
1392		.name	= "s3c64xx-spi",
1393		.pm = &s3c64xx_spi_pm,
1394		.of_match_table = of_match_ptr(s3c64xx_spi_dt_match),
1395	},
1396	.probe = s3c64xx_spi_probe,
1397	.remove = s3c64xx_spi_remove,
1398	.id_table = s3c64xx_spi_driver_ids,
1399};
1400MODULE_ALIAS("platform:s3c64xx-spi");
1401
1402module_platform_driver(s3c64xx_spi_driver);
1403
1404MODULE_AUTHOR("Jaswinder Singh <jassi.brar@samsung.com>");
1405MODULE_DESCRIPTION("S3C64XX SPI Controller Driver");
1406MODULE_LICENSE("GPL");
1407