xref: /linux/drivers/spi/spi-s3c64xx.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
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  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18  */
19 
20 #include <linux/init.h>
21 #include <linux/module.h>
22 #include <linux/workqueue.h>
23 #include <linux/interrupt.h>
24 #include <linux/delay.h>
25 #include <linux/clk.h>
26 #include <linux/dma-mapping.h>
27 #include <linux/platform_device.h>
28 #include <linux/pm_runtime.h>
29 #include <linux/spi/spi.h>
30 #include <linux/gpio.h>
31 #include <linux/of.h>
32 #include <linux/of_gpio.h>
33 
34 #include <mach/dma.h>
35 #include <linux/platform_data/spi-s3c64xx.h>
36 
37 #define MAX_SPI_PORTS		3
38 
39 /* Registers and bit-fields */
40 
41 #define S3C64XX_SPI_CH_CFG		0x00
42 #define S3C64XX_SPI_CLK_CFG		0x04
43 #define S3C64XX_SPI_MODE_CFG	0x08
44 #define S3C64XX_SPI_SLAVE_SEL	0x0C
45 #define S3C64XX_SPI_INT_EN		0x10
46 #define S3C64XX_SPI_STATUS		0x14
47 #define S3C64XX_SPI_TX_DATA		0x18
48 #define S3C64XX_SPI_RX_DATA		0x1C
49 #define S3C64XX_SPI_PACKET_CNT	0x20
50 #define S3C64XX_SPI_PENDING_CLR	0x24
51 #define S3C64XX_SPI_SWAP_CFG	0x28
52 #define S3C64XX_SPI_FB_CLK		0x2C
53 
54 #define S3C64XX_SPI_CH_HS_EN		(1<<6)	/* High Speed Enable */
55 #define S3C64XX_SPI_CH_SW_RST		(1<<5)
56 #define S3C64XX_SPI_CH_SLAVE		(1<<4)
57 #define S3C64XX_SPI_CPOL_L		(1<<3)
58 #define S3C64XX_SPI_CPHA_B		(1<<2)
59 #define S3C64XX_SPI_CH_RXCH_ON		(1<<1)
60 #define S3C64XX_SPI_CH_TXCH_ON		(1<<0)
61 
62 #define S3C64XX_SPI_CLKSEL_SRCMSK	(3<<9)
63 #define S3C64XX_SPI_CLKSEL_SRCSHFT	9
64 #define S3C64XX_SPI_ENCLK_ENABLE	(1<<8)
65 #define S3C64XX_SPI_PSR_MASK 		0xff
66 
67 #define S3C64XX_SPI_MODE_CH_TSZ_BYTE		(0<<29)
68 #define S3C64XX_SPI_MODE_CH_TSZ_HALFWORD	(1<<29)
69 #define S3C64XX_SPI_MODE_CH_TSZ_WORD		(2<<29)
70 #define S3C64XX_SPI_MODE_CH_TSZ_MASK		(3<<29)
71 #define S3C64XX_SPI_MODE_BUS_TSZ_BYTE		(0<<17)
72 #define S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD	(1<<17)
73 #define S3C64XX_SPI_MODE_BUS_TSZ_WORD		(2<<17)
74 #define S3C64XX_SPI_MODE_BUS_TSZ_MASK		(3<<17)
75 #define S3C64XX_SPI_MODE_RXDMA_ON		(1<<2)
76 #define S3C64XX_SPI_MODE_TXDMA_ON		(1<<1)
77 #define S3C64XX_SPI_MODE_4BURST			(1<<0)
78 
79 #define S3C64XX_SPI_SLAVE_AUTO			(1<<1)
80 #define S3C64XX_SPI_SLAVE_SIG_INACT		(1<<0)
81 
82 #define S3C64XX_SPI_INT_TRAILING_EN		(1<<6)
83 #define S3C64XX_SPI_INT_RX_OVERRUN_EN		(1<<5)
84 #define S3C64XX_SPI_INT_RX_UNDERRUN_EN		(1<<4)
85 #define S3C64XX_SPI_INT_TX_OVERRUN_EN		(1<<3)
86 #define S3C64XX_SPI_INT_TX_UNDERRUN_EN		(1<<2)
87 #define S3C64XX_SPI_INT_RX_FIFORDY_EN		(1<<1)
88 #define S3C64XX_SPI_INT_TX_FIFORDY_EN		(1<<0)
89 
90 #define S3C64XX_SPI_ST_RX_OVERRUN_ERR		(1<<5)
91 #define S3C64XX_SPI_ST_RX_UNDERRUN_ERR	(1<<4)
92 #define S3C64XX_SPI_ST_TX_OVERRUN_ERR		(1<<3)
93 #define S3C64XX_SPI_ST_TX_UNDERRUN_ERR	(1<<2)
94 #define S3C64XX_SPI_ST_RX_FIFORDY		(1<<1)
95 #define S3C64XX_SPI_ST_TX_FIFORDY		(1<<0)
96 
97 #define S3C64XX_SPI_PACKET_CNT_EN		(1<<16)
98 
99 #define S3C64XX_SPI_PND_TX_UNDERRUN_CLR		(1<<4)
100 #define S3C64XX_SPI_PND_TX_OVERRUN_CLR		(1<<3)
101 #define S3C64XX_SPI_PND_RX_UNDERRUN_CLR		(1<<2)
102 #define S3C64XX_SPI_PND_RX_OVERRUN_CLR		(1<<1)
103 #define S3C64XX_SPI_PND_TRAILING_CLR		(1<<0)
104 
105 #define S3C64XX_SPI_SWAP_RX_HALF_WORD		(1<<7)
106 #define S3C64XX_SPI_SWAP_RX_BYTE		(1<<6)
107 #define S3C64XX_SPI_SWAP_RX_BIT			(1<<5)
108 #define S3C64XX_SPI_SWAP_RX_EN			(1<<4)
109 #define S3C64XX_SPI_SWAP_TX_HALF_WORD		(1<<3)
110 #define S3C64XX_SPI_SWAP_TX_BYTE		(1<<2)
111 #define S3C64XX_SPI_SWAP_TX_BIT			(1<<1)
112 #define S3C64XX_SPI_SWAP_TX_EN			(1<<0)
113 
114 #define S3C64XX_SPI_FBCLK_MSK		(3<<0)
115 
116 #define FIFO_LVL_MASK(i) ((i)->port_conf->fifo_lvl_mask[i->port_id])
117 #define S3C64XX_SPI_ST_TX_DONE(v, i) (((v) & \
118 				(1 << (i)->port_conf->tx_st_done)) ? 1 : 0)
119 #define TX_FIFO_LVL(v, i) (((v) >> 6) & FIFO_LVL_MASK(i))
120 #define RX_FIFO_LVL(v, i) (((v) >> (i)->port_conf->rx_lvl_offset) & \
121 					FIFO_LVL_MASK(i))
122 
123 #define S3C64XX_SPI_MAX_TRAILCNT	0x3ff
124 #define S3C64XX_SPI_TRAILCNT_OFF	19
125 
126 #define S3C64XX_SPI_TRAILCNT		S3C64XX_SPI_MAX_TRAILCNT
127 
128 #define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
129 
130 #define RXBUSY    (1<<2)
131 #define TXBUSY    (1<<3)
132 
133 struct s3c64xx_spi_dma_data {
134 	unsigned		ch;
135 	enum dma_transfer_direction direction;
136 	enum dma_ch	dmach;
137 	struct property		*dma_prop;
138 };
139 
140 /**
141  * struct s3c64xx_spi_info - SPI Controller hardware info
142  * @fifo_lvl_mask: Bit-mask for {TX|RX}_FIFO_LVL bits in SPI_STATUS register.
143  * @rx_lvl_offset: Bit offset of RX_FIFO_LVL bits in SPI_STATUS regiter.
144  * @tx_st_done: Bit offset of TX_DONE bit in SPI_STATUS regiter.
145  * @high_speed: True, if the controller supports HIGH_SPEED_EN bit.
146  * @clk_from_cmu: True, if the controller does not include a clock mux and
147  *	prescaler unit.
148  *
149  * The Samsung s3c64xx SPI controller are used on various Samsung SoC's but
150  * differ in some aspects such as the size of the fifo and spi bus clock
151  * setup. Such differences are specified to the driver using this structure
152  * which is provided as driver data to the driver.
153  */
154 struct s3c64xx_spi_port_config {
155 	int	fifo_lvl_mask[MAX_SPI_PORTS];
156 	int	rx_lvl_offset;
157 	int	tx_st_done;
158 	bool	high_speed;
159 	bool	clk_from_cmu;
160 };
161 
162 /**
163  * struct s3c64xx_spi_driver_data - Runtime info holder for SPI driver.
164  * @clk: Pointer to the spi clock.
165  * @src_clk: Pointer to the clock used to generate SPI signals.
166  * @master: Pointer to the SPI Protocol master.
167  * @cntrlr_info: Platform specific data for the controller this driver manages.
168  * @tgl_spi: Pointer to the last CS left untoggled by the cs_change hint.
169  * @queue: To log SPI xfer requests.
170  * @lock: Controller specific lock.
171  * @state: Set of FLAGS to indicate status.
172  * @rx_dmach: Controller's DMA channel for Rx.
173  * @tx_dmach: Controller's DMA channel for Tx.
174  * @sfr_start: BUS address of SPI controller regs.
175  * @regs: Pointer to ioremap'ed controller registers.
176  * @irq: interrupt
177  * @xfer_completion: To indicate completion of xfer task.
178  * @cur_mode: Stores the active configuration of the controller.
179  * @cur_bpw: Stores the active bits per word settings.
180  * @cur_speed: Stores the active xfer clock speed.
181  */
182 struct s3c64xx_spi_driver_data {
183 	void __iomem                    *regs;
184 	struct clk                      *clk;
185 	struct clk                      *src_clk;
186 	struct platform_device          *pdev;
187 	struct spi_master               *master;
188 	struct s3c64xx_spi_info  *cntrlr_info;
189 	struct spi_device               *tgl_spi;
190 	struct list_head                queue;
191 	spinlock_t                      lock;
192 	unsigned long                   sfr_start;
193 	struct completion               xfer_completion;
194 	unsigned                        state;
195 	unsigned                        cur_mode, cur_bpw;
196 	unsigned                        cur_speed;
197 	struct s3c64xx_spi_dma_data	rx_dma;
198 	struct s3c64xx_spi_dma_data	tx_dma;
199 	struct samsung_dma_ops		*ops;
200 	struct s3c64xx_spi_port_config	*port_conf;
201 	unsigned int			port_id;
202 	unsigned long			gpios[4];
203 };
204 
205 static struct s3c2410_dma_client s3c64xx_spi_dma_client = {
206 	.name = "samsung-spi-dma",
207 };
208 
209 static void flush_fifo(struct s3c64xx_spi_driver_data *sdd)
210 {
211 	void __iomem *regs = sdd->regs;
212 	unsigned long loops;
213 	u32 val;
214 
215 	writel(0, regs + S3C64XX_SPI_PACKET_CNT);
216 
217 	val = readl(regs + S3C64XX_SPI_CH_CFG);
218 	val |= S3C64XX_SPI_CH_SW_RST;
219 	val &= ~S3C64XX_SPI_CH_HS_EN;
220 	writel(val, regs + S3C64XX_SPI_CH_CFG);
221 
222 	/* Flush TxFIFO*/
223 	loops = msecs_to_loops(1);
224 	do {
225 		val = readl(regs + S3C64XX_SPI_STATUS);
226 	} while (TX_FIFO_LVL(val, sdd) && loops--);
227 
228 	if (loops == 0)
229 		dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n");
230 
231 	/* Flush RxFIFO*/
232 	loops = msecs_to_loops(1);
233 	do {
234 		val = readl(regs + S3C64XX_SPI_STATUS);
235 		if (RX_FIFO_LVL(val, sdd))
236 			readl(regs + S3C64XX_SPI_RX_DATA);
237 		else
238 			break;
239 	} while (loops--);
240 
241 	if (loops == 0)
242 		dev_warn(&sdd->pdev->dev, "Timed out flushing RX FIFO\n");
243 
244 	val = readl(regs + S3C64XX_SPI_CH_CFG);
245 	val &= ~S3C64XX_SPI_CH_SW_RST;
246 	writel(val, regs + S3C64XX_SPI_CH_CFG);
247 
248 	val = readl(regs + S3C64XX_SPI_MODE_CFG);
249 	val &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
250 	writel(val, regs + S3C64XX_SPI_MODE_CFG);
251 
252 	val = readl(regs + S3C64XX_SPI_CH_CFG);
253 	val &= ~(S3C64XX_SPI_CH_RXCH_ON | S3C64XX_SPI_CH_TXCH_ON);
254 	writel(val, regs + S3C64XX_SPI_CH_CFG);
255 }
256 
257 static void s3c64xx_spi_dmacb(void *data)
258 {
259 	struct s3c64xx_spi_driver_data *sdd;
260 	struct s3c64xx_spi_dma_data *dma = data;
261 	unsigned long flags;
262 
263 	if (dma->direction == DMA_DEV_TO_MEM)
264 		sdd = container_of(data,
265 			struct s3c64xx_spi_driver_data, rx_dma);
266 	else
267 		sdd = container_of(data,
268 			struct s3c64xx_spi_driver_data, tx_dma);
269 
270 	spin_lock_irqsave(&sdd->lock, flags);
271 
272 	if (dma->direction == DMA_DEV_TO_MEM) {
273 		sdd->state &= ~RXBUSY;
274 		if (!(sdd->state & TXBUSY))
275 			complete(&sdd->xfer_completion);
276 	} else {
277 		sdd->state &= ~TXBUSY;
278 		if (!(sdd->state & RXBUSY))
279 			complete(&sdd->xfer_completion);
280 	}
281 
282 	spin_unlock_irqrestore(&sdd->lock, flags);
283 }
284 
285 static void prepare_dma(struct s3c64xx_spi_dma_data *dma,
286 					unsigned len, dma_addr_t buf)
287 {
288 	struct s3c64xx_spi_driver_data *sdd;
289 	struct samsung_dma_prep info;
290 	struct samsung_dma_config config;
291 
292 	if (dma->direction == DMA_DEV_TO_MEM) {
293 		sdd = container_of((void *)dma,
294 			struct s3c64xx_spi_driver_data, rx_dma);
295 		config.direction = sdd->rx_dma.direction;
296 		config.fifo = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
297 		config.width = sdd->cur_bpw / 8;
298 		sdd->ops->config(sdd->rx_dma.ch, &config);
299 	} else {
300 		sdd = container_of((void *)dma,
301 			struct s3c64xx_spi_driver_data, tx_dma);
302 		config.direction =  sdd->tx_dma.direction;
303 		config.fifo = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
304 		config.width = sdd->cur_bpw / 8;
305 		sdd->ops->config(sdd->tx_dma.ch, &config);
306 	}
307 
308 	info.cap = DMA_SLAVE;
309 	info.len = len;
310 	info.fp = s3c64xx_spi_dmacb;
311 	info.fp_param = dma;
312 	info.direction = dma->direction;
313 	info.buf = buf;
314 
315 	sdd->ops->prepare(dma->ch, &info);
316 	sdd->ops->trigger(dma->ch);
317 }
318 
319 static int acquire_dma(struct s3c64xx_spi_driver_data *sdd)
320 {
321 	struct samsung_dma_req req;
322 
323 	sdd->ops = samsung_dma_get_ops();
324 
325 	req.cap = DMA_SLAVE;
326 	req.client = &s3c64xx_spi_dma_client;
327 
328 	req.dt_dmach_prop = sdd->rx_dma.dma_prop;
329 	sdd->rx_dma.ch = sdd->ops->request(sdd->rx_dma.dmach, &req);
330 	req.dt_dmach_prop = sdd->tx_dma.dma_prop;
331 	sdd->tx_dma.ch = sdd->ops->request(sdd->tx_dma.dmach, &req);
332 
333 	return 1;
334 }
335 
336 static void enable_datapath(struct s3c64xx_spi_driver_data *sdd,
337 				struct spi_device *spi,
338 				struct spi_transfer *xfer, int dma_mode)
339 {
340 	void __iomem *regs = sdd->regs;
341 	u32 modecfg, chcfg;
342 
343 	modecfg = readl(regs + S3C64XX_SPI_MODE_CFG);
344 	modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
345 
346 	chcfg = readl(regs + S3C64XX_SPI_CH_CFG);
347 	chcfg &= ~S3C64XX_SPI_CH_TXCH_ON;
348 
349 	if (dma_mode) {
350 		chcfg &= ~S3C64XX_SPI_CH_RXCH_ON;
351 	} else {
352 		/* Always shift in data in FIFO, even if xfer is Tx only,
353 		 * this helps setting PCKT_CNT value for generating clocks
354 		 * as exactly needed.
355 		 */
356 		chcfg |= S3C64XX_SPI_CH_RXCH_ON;
357 		writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
358 					| S3C64XX_SPI_PACKET_CNT_EN,
359 					regs + S3C64XX_SPI_PACKET_CNT);
360 	}
361 
362 	if (xfer->tx_buf != NULL) {
363 		sdd->state |= TXBUSY;
364 		chcfg |= S3C64XX_SPI_CH_TXCH_ON;
365 		if (dma_mode) {
366 			modecfg |= S3C64XX_SPI_MODE_TXDMA_ON;
367 			prepare_dma(&sdd->tx_dma, xfer->len, xfer->tx_dma);
368 		} else {
369 			switch (sdd->cur_bpw) {
370 			case 32:
371 				iowrite32_rep(regs + S3C64XX_SPI_TX_DATA,
372 					xfer->tx_buf, xfer->len / 4);
373 				break;
374 			case 16:
375 				iowrite16_rep(regs + S3C64XX_SPI_TX_DATA,
376 					xfer->tx_buf, xfer->len / 2);
377 				break;
378 			default:
379 				iowrite8_rep(regs + S3C64XX_SPI_TX_DATA,
380 					xfer->tx_buf, xfer->len);
381 				break;
382 			}
383 		}
384 	}
385 
386 	if (xfer->rx_buf != NULL) {
387 		sdd->state |= RXBUSY;
388 
389 		if (sdd->port_conf->high_speed && sdd->cur_speed >= 30000000UL
390 					&& !(sdd->cur_mode & SPI_CPHA))
391 			chcfg |= S3C64XX_SPI_CH_HS_EN;
392 
393 		if (dma_mode) {
394 			modecfg |= S3C64XX_SPI_MODE_RXDMA_ON;
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 			prepare_dma(&sdd->rx_dma, xfer->len, xfer->rx_dma);
400 		}
401 	}
402 
403 	writel(modecfg, regs + S3C64XX_SPI_MODE_CFG);
404 	writel(chcfg, regs + S3C64XX_SPI_CH_CFG);
405 }
406 
407 static inline void enable_cs(struct s3c64xx_spi_driver_data *sdd,
408 						struct spi_device *spi)
409 {
410 	struct s3c64xx_spi_csinfo *cs;
411 
412 	if (sdd->tgl_spi != NULL) { /* If last device toggled after mssg */
413 		if (sdd->tgl_spi != spi) { /* if last mssg on diff device */
414 			/* Deselect the last toggled device */
415 			cs = sdd->tgl_spi->controller_data;
416 			gpio_set_value(cs->line,
417 				spi->mode & SPI_CS_HIGH ? 0 : 1);
418 		}
419 		sdd->tgl_spi = NULL;
420 	}
421 
422 	cs = spi->controller_data;
423 	gpio_set_value(cs->line, spi->mode & SPI_CS_HIGH ? 1 : 0);
424 }
425 
426 static int wait_for_xfer(struct s3c64xx_spi_driver_data *sdd,
427 				struct spi_transfer *xfer, int dma_mode)
428 {
429 	void __iomem *regs = sdd->regs;
430 	unsigned long val;
431 	int ms;
432 
433 	/* millisecs to xfer 'len' bytes @ 'cur_speed' */
434 	ms = xfer->len * 8 * 1000 / sdd->cur_speed;
435 	ms += 10; /* some tolerance */
436 
437 	if (dma_mode) {
438 		val = msecs_to_jiffies(ms) + 10;
439 		val = wait_for_completion_timeout(&sdd->xfer_completion, val);
440 	} else {
441 		u32 status;
442 		val = msecs_to_loops(ms);
443 		do {
444 			status = readl(regs + S3C64XX_SPI_STATUS);
445 		} while (RX_FIFO_LVL(status, sdd) < xfer->len && --val);
446 	}
447 
448 	if (!val)
449 		return -EIO;
450 
451 	if (dma_mode) {
452 		u32 status;
453 
454 		/*
455 		 * DmaTx returns after simply writing data in the FIFO,
456 		 * w/o waiting for real transmission on the bus to finish.
457 		 * DmaRx returns only after Dma read data from FIFO which
458 		 * needs bus transmission to finish, so we don't worry if
459 		 * Xfer involved Rx(with or without Tx).
460 		 */
461 		if (xfer->rx_buf == NULL) {
462 			val = msecs_to_loops(10);
463 			status = readl(regs + S3C64XX_SPI_STATUS);
464 			while ((TX_FIFO_LVL(status, sdd)
465 				|| !S3C64XX_SPI_ST_TX_DONE(status, sdd))
466 					&& --val) {
467 				cpu_relax();
468 				status = readl(regs + S3C64XX_SPI_STATUS);
469 			}
470 
471 			if (!val)
472 				return -EIO;
473 		}
474 	} else {
475 		/* If it was only Tx */
476 		if (xfer->rx_buf == NULL) {
477 			sdd->state &= ~TXBUSY;
478 			return 0;
479 		}
480 
481 		switch (sdd->cur_bpw) {
482 		case 32:
483 			ioread32_rep(regs + S3C64XX_SPI_RX_DATA,
484 				xfer->rx_buf, xfer->len / 4);
485 			break;
486 		case 16:
487 			ioread16_rep(regs + S3C64XX_SPI_RX_DATA,
488 				xfer->rx_buf, xfer->len / 2);
489 			break;
490 		default:
491 			ioread8_rep(regs + S3C64XX_SPI_RX_DATA,
492 				xfer->rx_buf, xfer->len);
493 			break;
494 		}
495 		sdd->state &= ~RXBUSY;
496 	}
497 
498 	return 0;
499 }
500 
501 static inline void disable_cs(struct s3c64xx_spi_driver_data *sdd,
502 						struct spi_device *spi)
503 {
504 	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
505 
506 	if (sdd->tgl_spi == spi)
507 		sdd->tgl_spi = NULL;
508 
509 	gpio_set_value(cs->line, spi->mode & SPI_CS_HIGH ? 0 : 1);
510 }
511 
512 static void s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
513 {
514 	void __iomem *regs = sdd->regs;
515 	u32 val;
516 
517 	/* Disable Clock */
518 	if (sdd->port_conf->clk_from_cmu) {
519 		clk_disable_unprepare(sdd->src_clk);
520 	} else {
521 		val = readl(regs + S3C64XX_SPI_CLK_CFG);
522 		val &= ~S3C64XX_SPI_ENCLK_ENABLE;
523 		writel(val, regs + S3C64XX_SPI_CLK_CFG);
524 	}
525 
526 	/* Set Polarity and Phase */
527 	val = readl(regs + S3C64XX_SPI_CH_CFG);
528 	val &= ~(S3C64XX_SPI_CH_SLAVE |
529 			S3C64XX_SPI_CPOL_L |
530 			S3C64XX_SPI_CPHA_B);
531 
532 	if (sdd->cur_mode & SPI_CPOL)
533 		val |= S3C64XX_SPI_CPOL_L;
534 
535 	if (sdd->cur_mode & SPI_CPHA)
536 		val |= S3C64XX_SPI_CPHA_B;
537 
538 	writel(val, regs + S3C64XX_SPI_CH_CFG);
539 
540 	/* Set Channel & DMA Mode */
541 	val = readl(regs + S3C64XX_SPI_MODE_CFG);
542 	val &= ~(S3C64XX_SPI_MODE_BUS_TSZ_MASK
543 			| S3C64XX_SPI_MODE_CH_TSZ_MASK);
544 
545 	switch (sdd->cur_bpw) {
546 	case 32:
547 		val |= S3C64XX_SPI_MODE_BUS_TSZ_WORD;
548 		val |= S3C64XX_SPI_MODE_CH_TSZ_WORD;
549 		break;
550 	case 16:
551 		val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD;
552 		val |= S3C64XX_SPI_MODE_CH_TSZ_HALFWORD;
553 		break;
554 	default:
555 		val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE;
556 		val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE;
557 		break;
558 	}
559 
560 	writel(val, regs + S3C64XX_SPI_MODE_CFG);
561 
562 	if (sdd->port_conf->clk_from_cmu) {
563 		/* Configure Clock */
564 		/* There is half-multiplier before the SPI */
565 		clk_set_rate(sdd->src_clk, sdd->cur_speed * 2);
566 		/* Enable Clock */
567 		clk_prepare_enable(sdd->src_clk);
568 	} else {
569 		/* Configure Clock */
570 		val = readl(regs + S3C64XX_SPI_CLK_CFG);
571 		val &= ~S3C64XX_SPI_PSR_MASK;
572 		val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / 2 - 1)
573 				& S3C64XX_SPI_PSR_MASK);
574 		writel(val, regs + S3C64XX_SPI_CLK_CFG);
575 
576 		/* Enable Clock */
577 		val = readl(regs + S3C64XX_SPI_CLK_CFG);
578 		val |= S3C64XX_SPI_ENCLK_ENABLE;
579 		writel(val, regs + S3C64XX_SPI_CLK_CFG);
580 	}
581 }
582 
583 #define XFER_DMAADDR_INVALID DMA_BIT_MASK(32)
584 
585 static int s3c64xx_spi_map_mssg(struct s3c64xx_spi_driver_data *sdd,
586 						struct spi_message *msg)
587 {
588 	struct device *dev = &sdd->pdev->dev;
589 	struct spi_transfer *xfer;
590 
591 	if (msg->is_dma_mapped)
592 		return 0;
593 
594 	/* First mark all xfer unmapped */
595 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
596 		xfer->rx_dma = XFER_DMAADDR_INVALID;
597 		xfer->tx_dma = XFER_DMAADDR_INVALID;
598 	}
599 
600 	/* Map until end or first fail */
601 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
602 
603 		if (xfer->len <= ((FIFO_LVL_MASK(sdd) >> 1) + 1))
604 			continue;
605 
606 		if (xfer->tx_buf != NULL) {
607 			xfer->tx_dma = dma_map_single(dev,
608 					(void *)xfer->tx_buf, xfer->len,
609 					DMA_TO_DEVICE);
610 			if (dma_mapping_error(dev, xfer->tx_dma)) {
611 				dev_err(dev, "dma_map_single Tx failed\n");
612 				xfer->tx_dma = XFER_DMAADDR_INVALID;
613 				return -ENOMEM;
614 			}
615 		}
616 
617 		if (xfer->rx_buf != NULL) {
618 			xfer->rx_dma = dma_map_single(dev, xfer->rx_buf,
619 						xfer->len, DMA_FROM_DEVICE);
620 			if (dma_mapping_error(dev, xfer->rx_dma)) {
621 				dev_err(dev, "dma_map_single Rx failed\n");
622 				dma_unmap_single(dev, xfer->tx_dma,
623 						xfer->len, DMA_TO_DEVICE);
624 				xfer->tx_dma = XFER_DMAADDR_INVALID;
625 				xfer->rx_dma = XFER_DMAADDR_INVALID;
626 				return -ENOMEM;
627 			}
628 		}
629 	}
630 
631 	return 0;
632 }
633 
634 static void s3c64xx_spi_unmap_mssg(struct s3c64xx_spi_driver_data *sdd,
635 						struct spi_message *msg)
636 {
637 	struct device *dev = &sdd->pdev->dev;
638 	struct spi_transfer *xfer;
639 
640 	if (msg->is_dma_mapped)
641 		return;
642 
643 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
644 
645 		if (xfer->len <= ((FIFO_LVL_MASK(sdd) >> 1) + 1))
646 			continue;
647 
648 		if (xfer->rx_buf != NULL
649 				&& xfer->rx_dma != XFER_DMAADDR_INVALID)
650 			dma_unmap_single(dev, xfer->rx_dma,
651 						xfer->len, DMA_FROM_DEVICE);
652 
653 		if (xfer->tx_buf != NULL
654 				&& xfer->tx_dma != XFER_DMAADDR_INVALID)
655 			dma_unmap_single(dev, xfer->tx_dma,
656 						xfer->len, DMA_TO_DEVICE);
657 	}
658 }
659 
660 static int s3c64xx_spi_transfer_one_message(struct spi_master *master,
661 					    struct spi_message *msg)
662 {
663 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
664 	struct spi_device *spi = msg->spi;
665 	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
666 	struct spi_transfer *xfer;
667 	int status = 0, cs_toggle = 0;
668 	u32 speed;
669 	u8 bpw;
670 
671 	/* If Master's(controller) state differs from that needed by Slave */
672 	if (sdd->cur_speed != spi->max_speed_hz
673 			|| sdd->cur_mode != spi->mode
674 			|| sdd->cur_bpw != spi->bits_per_word) {
675 		sdd->cur_bpw = spi->bits_per_word;
676 		sdd->cur_speed = spi->max_speed_hz;
677 		sdd->cur_mode = spi->mode;
678 		s3c64xx_spi_config(sdd);
679 	}
680 
681 	/* Map all the transfers if needed */
682 	if (s3c64xx_spi_map_mssg(sdd, msg)) {
683 		dev_err(&spi->dev,
684 			"Xfer: Unable to map message buffers!\n");
685 		status = -ENOMEM;
686 		goto out;
687 	}
688 
689 	/* Configure feedback delay */
690 	writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK);
691 
692 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
693 
694 		unsigned long flags;
695 		int use_dma;
696 
697 		INIT_COMPLETION(sdd->xfer_completion);
698 
699 		/* Only BPW and Speed may change across transfers */
700 		bpw = xfer->bits_per_word ? : spi->bits_per_word;
701 		speed = xfer->speed_hz ? : spi->max_speed_hz;
702 
703 		if (xfer->len % (bpw / 8)) {
704 			dev_err(&spi->dev,
705 				"Xfer length(%u) not a multiple of word size(%u)\n",
706 				xfer->len, bpw / 8);
707 			status = -EIO;
708 			goto out;
709 		}
710 
711 		if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) {
712 			sdd->cur_bpw = bpw;
713 			sdd->cur_speed = speed;
714 			s3c64xx_spi_config(sdd);
715 		}
716 
717 		/* Polling method for xfers not bigger than FIFO capacity */
718 		if (xfer->len <= ((FIFO_LVL_MASK(sdd) >> 1) + 1))
719 			use_dma = 0;
720 		else
721 			use_dma = 1;
722 
723 		spin_lock_irqsave(&sdd->lock, flags);
724 
725 		/* Pending only which is to be done */
726 		sdd->state &= ~RXBUSY;
727 		sdd->state &= ~TXBUSY;
728 
729 		enable_datapath(sdd, spi, xfer, use_dma);
730 
731 		/* Slave Select */
732 		enable_cs(sdd, spi);
733 
734 		/* Start the signals */
735 		writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
736 
737 		spin_unlock_irqrestore(&sdd->lock, flags);
738 
739 		status = wait_for_xfer(sdd, xfer, use_dma);
740 
741 		/* Quiese the signals */
742 		writel(S3C64XX_SPI_SLAVE_SIG_INACT,
743 		       sdd->regs + S3C64XX_SPI_SLAVE_SEL);
744 
745 		if (status) {
746 			dev_err(&spi->dev, "I/O Error: "
747 				"rx-%d tx-%d res:rx-%c tx-%c len-%d\n",
748 				xfer->rx_buf ? 1 : 0, xfer->tx_buf ? 1 : 0,
749 				(sdd->state & RXBUSY) ? 'f' : 'p',
750 				(sdd->state & TXBUSY) ? 'f' : 'p',
751 				xfer->len);
752 
753 			if (use_dma) {
754 				if (xfer->tx_buf != NULL
755 						&& (sdd->state & TXBUSY))
756 					sdd->ops->stop(sdd->tx_dma.ch);
757 				if (xfer->rx_buf != NULL
758 						&& (sdd->state & RXBUSY))
759 					sdd->ops->stop(sdd->rx_dma.ch);
760 			}
761 
762 			goto out;
763 		}
764 
765 		if (xfer->delay_usecs)
766 			udelay(xfer->delay_usecs);
767 
768 		if (xfer->cs_change) {
769 			/* Hint that the next mssg is gonna be
770 			   for the same device */
771 			if (list_is_last(&xfer->transfer_list,
772 						&msg->transfers))
773 				cs_toggle = 1;
774 			else
775 				disable_cs(sdd, spi);
776 		}
777 
778 		msg->actual_length += xfer->len;
779 
780 		flush_fifo(sdd);
781 	}
782 
783 out:
784 	if (!cs_toggle || status)
785 		disable_cs(sdd, spi);
786 	else
787 		sdd->tgl_spi = spi;
788 
789 	s3c64xx_spi_unmap_mssg(sdd, msg);
790 
791 	msg->status = status;
792 
793 	spi_finalize_current_message(master);
794 
795 	return 0;
796 }
797 
798 static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
799 {
800 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
801 
802 	/* Acquire DMA channels */
803 	while (!acquire_dma(sdd))
804 		msleep(10);
805 
806 	pm_runtime_get_sync(&sdd->pdev->dev);
807 
808 	return 0;
809 }
810 
811 static int s3c64xx_spi_unprepare_transfer(struct spi_master *spi)
812 {
813 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
814 
815 	/* Free DMA channels */
816 	sdd->ops->release(sdd->rx_dma.ch, &s3c64xx_spi_dma_client);
817 	sdd->ops->release(sdd->tx_dma.ch, &s3c64xx_spi_dma_client);
818 
819 	pm_runtime_put(&sdd->pdev->dev);
820 
821 	return 0;
822 }
823 
824 static struct s3c64xx_spi_csinfo *s3c64xx_get_slave_ctrldata(
825 				struct s3c64xx_spi_driver_data *sdd,
826 				struct spi_device *spi)
827 {
828 	struct s3c64xx_spi_csinfo *cs;
829 	struct device_node *slave_np, *data_np = NULL;
830 	u32 fb_delay = 0;
831 
832 	slave_np = spi->dev.of_node;
833 	if (!slave_np) {
834 		dev_err(&spi->dev, "device node not found\n");
835 		return ERR_PTR(-EINVAL);
836 	}
837 
838 	data_np = of_get_child_by_name(slave_np, "controller-data");
839 	if (!data_np) {
840 		dev_err(&spi->dev, "child node 'controller-data' not found\n");
841 		return ERR_PTR(-EINVAL);
842 	}
843 
844 	cs = kzalloc(sizeof(*cs), GFP_KERNEL);
845 	if (!cs) {
846 		dev_err(&spi->dev, "could not allocate memory for controller"
847 					" data\n");
848 		of_node_put(data_np);
849 		return ERR_PTR(-ENOMEM);
850 	}
851 
852 	cs->line = of_get_named_gpio(data_np, "cs-gpio", 0);
853 	if (!gpio_is_valid(cs->line)) {
854 		dev_err(&spi->dev, "chip select gpio is not specified or "
855 					"invalid\n");
856 		kfree(cs);
857 		of_node_put(data_np);
858 		return ERR_PTR(-EINVAL);
859 	}
860 
861 	of_property_read_u32(data_np, "samsung,spi-feedback-delay", &fb_delay);
862 	cs->fb_delay = fb_delay;
863 	of_node_put(data_np);
864 	return cs;
865 }
866 
867 /*
868  * Here we only check the validity of requested configuration
869  * and save the configuration in a local data-structure.
870  * The controller is actually configured only just before we
871  * get a message to transfer.
872  */
873 static int s3c64xx_spi_setup(struct spi_device *spi)
874 {
875 	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
876 	struct s3c64xx_spi_driver_data *sdd;
877 	struct s3c64xx_spi_info *sci;
878 	struct spi_message *msg;
879 	unsigned long flags;
880 	int err;
881 
882 	sdd = spi_master_get_devdata(spi->master);
883 	if (!cs && spi->dev.of_node) {
884 		cs = s3c64xx_get_slave_ctrldata(sdd, spi);
885 		spi->controller_data = cs;
886 	}
887 
888 	if (IS_ERR_OR_NULL(cs)) {
889 		dev_err(&spi->dev, "No CS for SPI(%d)\n", spi->chip_select);
890 		return -ENODEV;
891 	}
892 
893 	if (!spi_get_ctldata(spi)) {
894 		err = gpio_request_one(cs->line, GPIOF_OUT_INIT_HIGH,
895 				       dev_name(&spi->dev));
896 		if (err) {
897 			dev_err(&spi->dev,
898 				"Failed to get /CS gpio [%d]: %d\n",
899 				cs->line, err);
900 			goto err_gpio_req;
901 		}
902 		spi_set_ctldata(spi, cs);
903 	}
904 
905 	sci = sdd->cntrlr_info;
906 
907 	spin_lock_irqsave(&sdd->lock, flags);
908 
909 	list_for_each_entry(msg, &sdd->queue, queue) {
910 		/* Is some mssg is already queued for this device */
911 		if (msg->spi == spi) {
912 			dev_err(&spi->dev,
913 				"setup: attempt while mssg in queue!\n");
914 			spin_unlock_irqrestore(&sdd->lock, flags);
915 			err = -EBUSY;
916 			goto err_msgq;
917 		}
918 	}
919 
920 	spin_unlock_irqrestore(&sdd->lock, flags);
921 
922 	if (spi->bits_per_word != 8
923 			&& spi->bits_per_word != 16
924 			&& spi->bits_per_word != 32) {
925 		dev_err(&spi->dev, "setup: %dbits/wrd not supported!\n",
926 							spi->bits_per_word);
927 		err = -EINVAL;
928 		goto setup_exit;
929 	}
930 
931 	pm_runtime_get_sync(&sdd->pdev->dev);
932 
933 	/* Check if we can provide the requested rate */
934 	if (!sdd->port_conf->clk_from_cmu) {
935 		u32 psr, speed;
936 
937 		/* Max possible */
938 		speed = clk_get_rate(sdd->src_clk) / 2 / (0 + 1);
939 
940 		if (spi->max_speed_hz > speed)
941 			spi->max_speed_hz = speed;
942 
943 		psr = clk_get_rate(sdd->src_clk) / 2 / spi->max_speed_hz - 1;
944 		psr &= S3C64XX_SPI_PSR_MASK;
945 		if (psr == S3C64XX_SPI_PSR_MASK)
946 			psr--;
947 
948 		speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
949 		if (spi->max_speed_hz < speed) {
950 			if (psr+1 < S3C64XX_SPI_PSR_MASK) {
951 				psr++;
952 			} else {
953 				err = -EINVAL;
954 				goto setup_exit;
955 			}
956 		}
957 
958 		speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
959 		if (spi->max_speed_hz >= speed) {
960 			spi->max_speed_hz = speed;
961 		} else {
962 			err = -EINVAL;
963 			goto setup_exit;
964 		}
965 	}
966 
967 	pm_runtime_put(&sdd->pdev->dev);
968 	disable_cs(sdd, spi);
969 	return 0;
970 
971 setup_exit:
972 	/* setup() returns with device de-selected */
973 	disable_cs(sdd, spi);
974 
975 err_msgq:
976 	gpio_free(cs->line);
977 	spi_set_ctldata(spi, NULL);
978 
979 err_gpio_req:
980 	if (spi->dev.of_node)
981 		kfree(cs);
982 
983 	return err;
984 }
985 
986 static void s3c64xx_spi_cleanup(struct spi_device *spi)
987 {
988 	struct s3c64xx_spi_csinfo *cs = spi_get_ctldata(spi);
989 
990 	if (cs) {
991 		gpio_free(cs->line);
992 		if (spi->dev.of_node)
993 			kfree(cs);
994 	}
995 	spi_set_ctldata(spi, NULL);
996 }
997 
998 static irqreturn_t s3c64xx_spi_irq(int irq, void *data)
999 {
1000 	struct s3c64xx_spi_driver_data *sdd = data;
1001 	struct spi_master *spi = sdd->master;
1002 	unsigned int val;
1003 
1004 	val = readl(sdd->regs + S3C64XX_SPI_PENDING_CLR);
1005 
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 
1011 	writel(val, sdd->regs + S3C64XX_SPI_PENDING_CLR);
1012 
1013 	if (val & S3C64XX_SPI_PND_RX_OVERRUN_CLR)
1014 		dev_err(&spi->dev, "RX overrun\n");
1015 	if (val & S3C64XX_SPI_PND_RX_UNDERRUN_CLR)
1016 		dev_err(&spi->dev, "RX underrun\n");
1017 	if (val & S3C64XX_SPI_PND_TX_OVERRUN_CLR)
1018 		dev_err(&spi->dev, "TX overrun\n");
1019 	if (val & S3C64XX_SPI_PND_TX_UNDERRUN_CLR)
1020 		dev_err(&spi->dev, "TX underrun\n");
1021 
1022 	return IRQ_HANDLED;
1023 }
1024 
1025 static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd, int channel)
1026 {
1027 	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1028 	void __iomem *regs = sdd->regs;
1029 	unsigned int val;
1030 
1031 	sdd->cur_speed = 0;
1032 
1033 	writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
1034 
1035 	/* Disable Interrupts - we use Polling if not DMA mode */
1036 	writel(0, regs + S3C64XX_SPI_INT_EN);
1037 
1038 	if (!sdd->port_conf->clk_from_cmu)
1039 		writel(sci->src_clk_nr << S3C64XX_SPI_CLKSEL_SRCSHFT,
1040 				regs + S3C64XX_SPI_CLK_CFG);
1041 	writel(0, regs + S3C64XX_SPI_MODE_CFG);
1042 	writel(0, regs + S3C64XX_SPI_PACKET_CNT);
1043 
1044 	/* Clear any irq pending bits */
1045 	writel(readl(regs + S3C64XX_SPI_PENDING_CLR),
1046 				regs + S3C64XX_SPI_PENDING_CLR);
1047 
1048 	writel(0, regs + S3C64XX_SPI_SWAP_CFG);
1049 
1050 	val = readl(regs + S3C64XX_SPI_MODE_CFG);
1051 	val &= ~S3C64XX_SPI_MODE_4BURST;
1052 	val &= ~(S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
1053 	val |= (S3C64XX_SPI_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
1054 	writel(val, regs + S3C64XX_SPI_MODE_CFG);
1055 
1056 	flush_fifo(sdd);
1057 }
1058 
1059 static int s3c64xx_spi_get_dmares(
1060 			struct s3c64xx_spi_driver_data *sdd, bool tx)
1061 {
1062 	struct platform_device *pdev = sdd->pdev;
1063 	struct s3c64xx_spi_dma_data *dma_data;
1064 	struct property *prop;
1065 	struct resource *res;
1066 	char prop_name[15], *chan_str;
1067 
1068 	if (tx) {
1069 		dma_data = &sdd->tx_dma;
1070 		dma_data->direction = DMA_MEM_TO_DEV;
1071 		chan_str = "tx";
1072 	} else {
1073 		dma_data = &sdd->rx_dma;
1074 		dma_data->direction = DMA_DEV_TO_MEM;
1075 		chan_str = "rx";
1076 	}
1077 
1078 	if (!sdd->pdev->dev.of_node) {
1079 		res = platform_get_resource(pdev, IORESOURCE_DMA, tx ? 0 : 1);
1080 		if (!res) {
1081 			dev_err(&pdev->dev, "Unable to get SPI-%s dma "
1082 					"resource\n", chan_str);
1083 			return -ENXIO;
1084 		}
1085 		dma_data->dmach = res->start;
1086 		return 0;
1087 	}
1088 
1089 	sprintf(prop_name, "%s-dma-channel", chan_str);
1090 	prop = of_find_property(pdev->dev.of_node, prop_name, NULL);
1091 	if (!prop) {
1092 		dev_err(&pdev->dev, "%s dma channel property not specified\n",
1093 					chan_str);
1094 		return -ENXIO;
1095 	}
1096 
1097 	dma_data->dmach = DMACH_DT_PROP;
1098 	dma_data->dma_prop = prop;
1099 	return 0;
1100 }
1101 
1102 #ifdef CONFIG_OF
1103 static int s3c64xx_spi_parse_dt_gpio(struct s3c64xx_spi_driver_data *sdd)
1104 {
1105 	struct device *dev = &sdd->pdev->dev;
1106 	int idx, gpio, ret;
1107 
1108 	/* find gpios for mosi, miso and clock lines */
1109 	for (idx = 0; idx < 3; idx++) {
1110 		gpio = of_get_gpio(dev->of_node, idx);
1111 		if (!gpio_is_valid(gpio)) {
1112 			dev_err(dev, "invalid gpio[%d]: %d\n", idx, gpio);
1113 			goto free_gpio;
1114 		}
1115 		sdd->gpios[idx] = gpio;
1116 		ret = gpio_request(gpio, "spi-bus");
1117 		if (ret) {
1118 			dev_err(dev, "gpio [%d] request failed: %d\n",
1119 				gpio, ret);
1120 			goto free_gpio;
1121 		}
1122 	}
1123 	return 0;
1124 
1125 free_gpio:
1126 	while (--idx >= 0)
1127 		gpio_free(sdd->gpios[idx]);
1128 	return -EINVAL;
1129 }
1130 
1131 static void s3c64xx_spi_dt_gpio_free(struct s3c64xx_spi_driver_data *sdd)
1132 {
1133 	unsigned int idx;
1134 	for (idx = 0; idx < 3; idx++)
1135 		gpio_free(sdd->gpios[idx]);
1136 }
1137 
1138 static struct s3c64xx_spi_info * s3c64xx_spi_parse_dt(
1139 						struct device *dev)
1140 {
1141 	struct s3c64xx_spi_info *sci;
1142 	u32 temp;
1143 
1144 	sci = devm_kzalloc(dev, sizeof(*sci), GFP_KERNEL);
1145 	if (!sci) {
1146 		dev_err(dev, "memory allocation for spi_info failed\n");
1147 		return ERR_PTR(-ENOMEM);
1148 	}
1149 
1150 	if (of_property_read_u32(dev->of_node, "samsung,spi-src-clk", &temp)) {
1151 		dev_warn(dev, "spi bus clock parent not specified, using "
1152 				"clock at index 0 as parent\n");
1153 		sci->src_clk_nr = 0;
1154 	} else {
1155 		sci->src_clk_nr = temp;
1156 	}
1157 
1158 	if (of_property_read_u32(dev->of_node, "num-cs", &temp)) {
1159 		dev_warn(dev, "number of chip select lines not specified, "
1160 				"assuming 1 chip select line\n");
1161 		sci->num_cs = 1;
1162 	} else {
1163 		sci->num_cs = temp;
1164 	}
1165 
1166 	return sci;
1167 }
1168 #else
1169 static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
1170 {
1171 	return dev->platform_data;
1172 }
1173 
1174 static int s3c64xx_spi_parse_dt_gpio(struct s3c64xx_spi_driver_data *sdd)
1175 {
1176 	return -EINVAL;
1177 }
1178 
1179 static void s3c64xx_spi_dt_gpio_free(struct s3c64xx_spi_driver_data *sdd)
1180 {
1181 }
1182 #endif
1183 
1184 static const struct of_device_id s3c64xx_spi_dt_match[];
1185 
1186 static inline struct s3c64xx_spi_port_config *s3c64xx_spi_get_port_config(
1187 						struct platform_device *pdev)
1188 {
1189 #ifdef CONFIG_OF
1190 	if (pdev->dev.of_node) {
1191 		const struct of_device_id *match;
1192 		match = of_match_node(s3c64xx_spi_dt_match, pdev->dev.of_node);
1193 		return (struct s3c64xx_spi_port_config *)match->data;
1194 	}
1195 #endif
1196 	return (struct s3c64xx_spi_port_config *)
1197 			 platform_get_device_id(pdev)->driver_data;
1198 }
1199 
1200 static int __init s3c64xx_spi_probe(struct platform_device *pdev)
1201 {
1202 	struct resource	*mem_res;
1203 	struct s3c64xx_spi_driver_data *sdd;
1204 	struct s3c64xx_spi_info *sci = pdev->dev.platform_data;
1205 	struct spi_master *master;
1206 	int ret, irq;
1207 	char clk_name[16];
1208 
1209 	if (!sci && pdev->dev.of_node) {
1210 		sci = s3c64xx_spi_parse_dt(&pdev->dev);
1211 		if (IS_ERR(sci))
1212 			return PTR_ERR(sci);
1213 	}
1214 
1215 	if (!sci) {
1216 		dev_err(&pdev->dev, "platform_data missing!\n");
1217 		return -ENODEV;
1218 	}
1219 
1220 	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1221 	if (mem_res == NULL) {
1222 		dev_err(&pdev->dev, "Unable to get SPI MEM resource\n");
1223 		return -ENXIO;
1224 	}
1225 
1226 	irq = platform_get_irq(pdev, 0);
1227 	if (irq < 0) {
1228 		dev_warn(&pdev->dev, "Failed to get IRQ: %d\n", irq);
1229 		return irq;
1230 	}
1231 
1232 	master = spi_alloc_master(&pdev->dev,
1233 				sizeof(struct s3c64xx_spi_driver_data));
1234 	if (master == NULL) {
1235 		dev_err(&pdev->dev, "Unable to allocate SPI Master\n");
1236 		return -ENOMEM;
1237 	}
1238 
1239 	platform_set_drvdata(pdev, master);
1240 
1241 	sdd = spi_master_get_devdata(master);
1242 	sdd->port_conf = s3c64xx_spi_get_port_config(pdev);
1243 	sdd->master = master;
1244 	sdd->cntrlr_info = sci;
1245 	sdd->pdev = pdev;
1246 	sdd->sfr_start = mem_res->start;
1247 	if (pdev->dev.of_node) {
1248 		ret = of_alias_get_id(pdev->dev.of_node, "spi");
1249 		if (ret < 0) {
1250 			dev_err(&pdev->dev, "failed to get alias id, "
1251 						"errno %d\n", ret);
1252 			goto err0;
1253 		}
1254 		sdd->port_id = ret;
1255 	} else {
1256 		sdd->port_id = pdev->id;
1257 	}
1258 
1259 	sdd->cur_bpw = 8;
1260 
1261 	ret = s3c64xx_spi_get_dmares(sdd, true);
1262 	if (ret)
1263 		goto err0;
1264 
1265 	ret = s3c64xx_spi_get_dmares(sdd, false);
1266 	if (ret)
1267 		goto err0;
1268 
1269 	master->dev.of_node = pdev->dev.of_node;
1270 	master->bus_num = sdd->port_id;
1271 	master->setup = s3c64xx_spi_setup;
1272 	master->cleanup = s3c64xx_spi_cleanup;
1273 	master->prepare_transfer_hardware = s3c64xx_spi_prepare_transfer;
1274 	master->transfer_one_message = s3c64xx_spi_transfer_one_message;
1275 	master->unprepare_transfer_hardware = s3c64xx_spi_unprepare_transfer;
1276 	master->num_chipselect = sci->num_cs;
1277 	master->dma_alignment = 8;
1278 	/* the spi->mode bits understood by this driver: */
1279 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1280 
1281 	sdd->regs = devm_request_and_ioremap(&pdev->dev, mem_res);
1282 	if (sdd->regs == NULL) {
1283 		dev_err(&pdev->dev, "Unable to remap IO\n");
1284 		ret = -ENXIO;
1285 		goto err1;
1286 	}
1287 
1288 	if (!sci->cfg_gpio && pdev->dev.of_node) {
1289 		if (s3c64xx_spi_parse_dt_gpio(sdd))
1290 			return -EBUSY;
1291 	} else if (sci->cfg_gpio == NULL || sci->cfg_gpio()) {
1292 		dev_err(&pdev->dev, "Unable to config gpio\n");
1293 		ret = -EBUSY;
1294 		goto err2;
1295 	}
1296 
1297 	/* Setup clocks */
1298 	sdd->clk = clk_get(&pdev->dev, "spi");
1299 	if (IS_ERR(sdd->clk)) {
1300 		dev_err(&pdev->dev, "Unable to acquire clock 'spi'\n");
1301 		ret = PTR_ERR(sdd->clk);
1302 		goto err3;
1303 	}
1304 
1305 	if (clk_prepare_enable(sdd->clk)) {
1306 		dev_err(&pdev->dev, "Couldn't enable clock 'spi'\n");
1307 		ret = -EBUSY;
1308 		goto err4;
1309 	}
1310 
1311 	sprintf(clk_name, "spi_busclk%d", sci->src_clk_nr);
1312 	sdd->src_clk = clk_get(&pdev->dev, clk_name);
1313 	if (IS_ERR(sdd->src_clk)) {
1314 		dev_err(&pdev->dev,
1315 			"Unable to acquire clock '%s'\n", clk_name);
1316 		ret = PTR_ERR(sdd->src_clk);
1317 		goto err5;
1318 	}
1319 
1320 	if (clk_prepare_enable(sdd->src_clk)) {
1321 		dev_err(&pdev->dev, "Couldn't enable clock '%s'\n", clk_name);
1322 		ret = -EBUSY;
1323 		goto err6;
1324 	}
1325 
1326 	/* Setup Deufult Mode */
1327 	s3c64xx_spi_hwinit(sdd, sdd->port_id);
1328 
1329 	spin_lock_init(&sdd->lock);
1330 	init_completion(&sdd->xfer_completion);
1331 	INIT_LIST_HEAD(&sdd->queue);
1332 
1333 	ret = request_irq(irq, s3c64xx_spi_irq, 0, "spi-s3c64xx", sdd);
1334 	if (ret != 0) {
1335 		dev_err(&pdev->dev, "Failed to request IRQ %d: %d\n",
1336 			irq, ret);
1337 		goto err7;
1338 	}
1339 
1340 	writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
1341 	       S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
1342 	       sdd->regs + S3C64XX_SPI_INT_EN);
1343 
1344 	if (spi_register_master(master)) {
1345 		dev_err(&pdev->dev, "cannot register SPI master\n");
1346 		ret = -EBUSY;
1347 		goto err8;
1348 	}
1349 
1350 	dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d "
1351 					"with %d Slaves attached\n",
1352 					sdd->port_id, master->num_chipselect);
1353 	dev_dbg(&pdev->dev, "\tIOmem=[0x%x-0x%x]\tDMA=[Rx-%d, Tx-%d]\n",
1354 					mem_res->end, mem_res->start,
1355 					sdd->rx_dma.dmach, sdd->tx_dma.dmach);
1356 
1357 	pm_runtime_enable(&pdev->dev);
1358 
1359 	return 0;
1360 
1361 err8:
1362 	free_irq(irq, sdd);
1363 err7:
1364 	clk_disable_unprepare(sdd->src_clk);
1365 err6:
1366 	clk_put(sdd->src_clk);
1367 err5:
1368 	clk_disable_unprepare(sdd->clk);
1369 err4:
1370 	clk_put(sdd->clk);
1371 err3:
1372 	if (!sdd->cntrlr_info->cfg_gpio && pdev->dev.of_node)
1373 		s3c64xx_spi_dt_gpio_free(sdd);
1374 err2:
1375 err1:
1376 err0:
1377 	platform_set_drvdata(pdev, NULL);
1378 	spi_master_put(master);
1379 
1380 	return ret;
1381 }
1382 
1383 static int s3c64xx_spi_remove(struct platform_device *pdev)
1384 {
1385 	struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
1386 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1387 
1388 	pm_runtime_disable(&pdev->dev);
1389 
1390 	spi_unregister_master(master);
1391 
1392 	writel(0, sdd->regs + S3C64XX_SPI_INT_EN);
1393 
1394 	free_irq(platform_get_irq(pdev, 0), sdd);
1395 
1396 	clk_disable_unprepare(sdd->src_clk);
1397 	clk_put(sdd->src_clk);
1398 
1399 	clk_disable_unprepare(sdd->clk);
1400 	clk_put(sdd->clk);
1401 
1402 	if (!sdd->cntrlr_info->cfg_gpio && pdev->dev.of_node)
1403 		s3c64xx_spi_dt_gpio_free(sdd);
1404 
1405 	platform_set_drvdata(pdev, NULL);
1406 	spi_master_put(master);
1407 
1408 	return 0;
1409 }
1410 
1411 #ifdef CONFIG_PM
1412 static int s3c64xx_spi_suspend(struct device *dev)
1413 {
1414 	struct spi_master *master = dev_get_drvdata(dev);
1415 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1416 
1417 	spi_master_suspend(master);
1418 
1419 	/* Disable the clock */
1420 	clk_disable_unprepare(sdd->src_clk);
1421 	clk_disable_unprepare(sdd->clk);
1422 
1423 	if (!sdd->cntrlr_info->cfg_gpio && dev->of_node)
1424 		s3c64xx_spi_dt_gpio_free(sdd);
1425 
1426 	sdd->cur_speed = 0; /* Output Clock is stopped */
1427 
1428 	return 0;
1429 }
1430 
1431 static int s3c64xx_spi_resume(struct device *dev)
1432 {
1433 	struct spi_master *master = dev_get_drvdata(dev);
1434 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1435 	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1436 
1437 	if (!sci->cfg_gpio && dev->of_node)
1438 		s3c64xx_spi_parse_dt_gpio(sdd);
1439 	else
1440 		sci->cfg_gpio();
1441 
1442 	/* Enable the clock */
1443 	clk_prepare_enable(sdd->src_clk);
1444 	clk_prepare_enable(sdd->clk);
1445 
1446 	s3c64xx_spi_hwinit(sdd, sdd->port_id);
1447 
1448 	spi_master_resume(master);
1449 
1450 	return 0;
1451 }
1452 #endif /* CONFIG_PM */
1453 
1454 #ifdef CONFIG_PM_RUNTIME
1455 static int s3c64xx_spi_runtime_suspend(struct device *dev)
1456 {
1457 	struct spi_master *master = dev_get_drvdata(dev);
1458 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1459 
1460 	clk_disable_unprepare(sdd->clk);
1461 	clk_disable_unprepare(sdd->src_clk);
1462 
1463 	return 0;
1464 }
1465 
1466 static int s3c64xx_spi_runtime_resume(struct device *dev)
1467 {
1468 	struct spi_master *master = dev_get_drvdata(dev);
1469 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1470 
1471 	clk_prepare_enable(sdd->src_clk);
1472 	clk_prepare_enable(sdd->clk);
1473 
1474 	return 0;
1475 }
1476 #endif /* CONFIG_PM_RUNTIME */
1477 
1478 static const struct dev_pm_ops s3c64xx_spi_pm = {
1479 	SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume)
1480 	SET_RUNTIME_PM_OPS(s3c64xx_spi_runtime_suspend,
1481 			   s3c64xx_spi_runtime_resume, NULL)
1482 };
1483 
1484 static struct s3c64xx_spi_port_config s3c2443_spi_port_config = {
1485 	.fifo_lvl_mask	= { 0x7f },
1486 	.rx_lvl_offset	= 13,
1487 	.tx_st_done	= 21,
1488 	.high_speed	= true,
1489 };
1490 
1491 static struct s3c64xx_spi_port_config s3c6410_spi_port_config = {
1492 	.fifo_lvl_mask	= { 0x7f, 0x7F },
1493 	.rx_lvl_offset	= 13,
1494 	.tx_st_done	= 21,
1495 };
1496 
1497 static struct s3c64xx_spi_port_config s5p64x0_spi_port_config = {
1498 	.fifo_lvl_mask	= { 0x1ff, 0x7F },
1499 	.rx_lvl_offset	= 15,
1500 	.tx_st_done	= 25,
1501 };
1502 
1503 static struct s3c64xx_spi_port_config s5pc100_spi_port_config = {
1504 	.fifo_lvl_mask	= { 0x7f, 0x7F },
1505 	.rx_lvl_offset	= 13,
1506 	.tx_st_done	= 21,
1507 	.high_speed	= true,
1508 };
1509 
1510 static struct s3c64xx_spi_port_config s5pv210_spi_port_config = {
1511 	.fifo_lvl_mask	= { 0x1ff, 0x7F },
1512 	.rx_lvl_offset	= 15,
1513 	.tx_st_done	= 25,
1514 	.high_speed	= true,
1515 };
1516 
1517 static struct s3c64xx_spi_port_config exynos4_spi_port_config = {
1518 	.fifo_lvl_mask	= { 0x1ff, 0x7F, 0x7F },
1519 	.rx_lvl_offset	= 15,
1520 	.tx_st_done	= 25,
1521 	.high_speed	= true,
1522 	.clk_from_cmu	= true,
1523 };
1524 
1525 static struct platform_device_id s3c64xx_spi_driver_ids[] = {
1526 	{
1527 		.name		= "s3c2443-spi",
1528 		.driver_data	= (kernel_ulong_t)&s3c2443_spi_port_config,
1529 	}, {
1530 		.name		= "s3c6410-spi",
1531 		.driver_data	= (kernel_ulong_t)&s3c6410_spi_port_config,
1532 	}, {
1533 		.name		= "s5p64x0-spi",
1534 		.driver_data	= (kernel_ulong_t)&s5p64x0_spi_port_config,
1535 	}, {
1536 		.name		= "s5pc100-spi",
1537 		.driver_data	= (kernel_ulong_t)&s5pc100_spi_port_config,
1538 	}, {
1539 		.name		= "s5pv210-spi",
1540 		.driver_data	= (kernel_ulong_t)&s5pv210_spi_port_config,
1541 	}, {
1542 		.name		= "exynos4210-spi",
1543 		.driver_data	= (kernel_ulong_t)&exynos4_spi_port_config,
1544 	},
1545 	{ },
1546 };
1547 
1548 #ifdef CONFIG_OF
1549 static const struct of_device_id s3c64xx_spi_dt_match[] = {
1550 	{ .compatible = "samsung,exynos4210-spi",
1551 			.data = (void *)&exynos4_spi_port_config,
1552 	},
1553 	{ },
1554 };
1555 MODULE_DEVICE_TABLE(of, s3c64xx_spi_dt_match);
1556 #endif /* CONFIG_OF */
1557 
1558 static struct platform_driver s3c64xx_spi_driver = {
1559 	.driver = {
1560 		.name	= "s3c64xx-spi",
1561 		.owner = THIS_MODULE,
1562 		.pm = &s3c64xx_spi_pm,
1563 		.of_match_table = of_match_ptr(s3c64xx_spi_dt_match),
1564 	},
1565 	.remove = s3c64xx_spi_remove,
1566 	.id_table = s3c64xx_spi_driver_ids,
1567 };
1568 MODULE_ALIAS("platform:s3c64xx-spi");
1569 
1570 static int __init s3c64xx_spi_init(void)
1571 {
1572 	return platform_driver_probe(&s3c64xx_spi_driver, s3c64xx_spi_probe);
1573 }
1574 subsys_initcall(s3c64xx_spi_init);
1575 
1576 static void __exit s3c64xx_spi_exit(void)
1577 {
1578 	platform_driver_unregister(&s3c64xx_spi_driver);
1579 }
1580 module_exit(s3c64xx_spi_exit);
1581 
1582 MODULE_AUTHOR("Jaswinder Singh <jassi.brar@samsung.com>");
1583 MODULE_DESCRIPTION("S3C64XX SPI Controller Driver");
1584 MODULE_LICENSE("GPL");
1585