xref: /linux/drivers/spi/spi-s3c64xx.c (revision b43ab901d671e3e3cad425ea5e9a3c74e266dcdd)
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/delay.h>
24 #include <linux/clk.h>
25 #include <linux/dma-mapping.h>
26 #include <linux/platform_device.h>
27 #include <linux/spi/spi.h>
28 
29 #include <mach/dma.h>
30 #include <plat/s3c64xx-spi.h>
31 
32 /* Registers and bit-fields */
33 
34 #define S3C64XX_SPI_CH_CFG		0x00
35 #define S3C64XX_SPI_CLK_CFG		0x04
36 #define S3C64XX_SPI_MODE_CFG	0x08
37 #define S3C64XX_SPI_SLAVE_SEL	0x0C
38 #define S3C64XX_SPI_INT_EN		0x10
39 #define S3C64XX_SPI_STATUS		0x14
40 #define S3C64XX_SPI_TX_DATA		0x18
41 #define S3C64XX_SPI_RX_DATA		0x1C
42 #define S3C64XX_SPI_PACKET_CNT	0x20
43 #define S3C64XX_SPI_PENDING_CLR	0x24
44 #define S3C64XX_SPI_SWAP_CFG	0x28
45 #define S3C64XX_SPI_FB_CLK		0x2C
46 
47 #define S3C64XX_SPI_CH_HS_EN		(1<<6)	/* High Speed Enable */
48 #define S3C64XX_SPI_CH_SW_RST		(1<<5)
49 #define S3C64XX_SPI_CH_SLAVE		(1<<4)
50 #define S3C64XX_SPI_CPOL_L		(1<<3)
51 #define S3C64XX_SPI_CPHA_B		(1<<2)
52 #define S3C64XX_SPI_CH_RXCH_ON		(1<<1)
53 #define S3C64XX_SPI_CH_TXCH_ON		(1<<0)
54 
55 #define S3C64XX_SPI_CLKSEL_SRCMSK	(3<<9)
56 #define S3C64XX_SPI_CLKSEL_SRCSHFT	9
57 #define S3C64XX_SPI_ENCLK_ENABLE	(1<<8)
58 #define S3C64XX_SPI_PSR_MASK 		0xff
59 
60 #define S3C64XX_SPI_MODE_CH_TSZ_BYTE		(0<<29)
61 #define S3C64XX_SPI_MODE_CH_TSZ_HALFWORD	(1<<29)
62 #define S3C64XX_SPI_MODE_CH_TSZ_WORD		(2<<29)
63 #define S3C64XX_SPI_MODE_CH_TSZ_MASK		(3<<29)
64 #define S3C64XX_SPI_MODE_BUS_TSZ_BYTE		(0<<17)
65 #define S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD	(1<<17)
66 #define S3C64XX_SPI_MODE_BUS_TSZ_WORD		(2<<17)
67 #define S3C64XX_SPI_MODE_BUS_TSZ_MASK		(3<<17)
68 #define S3C64XX_SPI_MODE_RXDMA_ON		(1<<2)
69 #define S3C64XX_SPI_MODE_TXDMA_ON		(1<<1)
70 #define S3C64XX_SPI_MODE_4BURST			(1<<0)
71 
72 #define S3C64XX_SPI_SLAVE_AUTO			(1<<1)
73 #define S3C64XX_SPI_SLAVE_SIG_INACT		(1<<0)
74 
75 #define S3C64XX_SPI_ACT(c) writel(0, (c)->regs + S3C64XX_SPI_SLAVE_SEL)
76 
77 #define S3C64XX_SPI_DEACT(c) writel(S3C64XX_SPI_SLAVE_SIG_INACT, \
78 					(c)->regs + S3C64XX_SPI_SLAVE_SEL)
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 S3C64XX_SPI_ST_TRLCNTZ(v, i) ((((v) >> (i)->rx_lvl_offset) & \
115 					(((i)->fifo_lvl_mask + 1))) \
116 					? 1 : 0)
117 
118 #define S3C64XX_SPI_ST_TX_DONE(v, i) (((v) & (1 << (i)->tx_st_done)) ? 1 : 0)
119 #define TX_FIFO_LVL(v, i) (((v) >> 6) & (i)->fifo_lvl_mask)
120 #define RX_FIFO_LVL(v, i) (((v) >> (i)->rx_lvl_offset) & (i)->fifo_lvl_mask)
121 
122 #define S3C64XX_SPI_MAX_TRAILCNT	0x3ff
123 #define S3C64XX_SPI_TRAILCNT_OFF	19
124 
125 #define S3C64XX_SPI_TRAILCNT		S3C64XX_SPI_MAX_TRAILCNT
126 
127 #define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
128 
129 #define SUSPND    (1<<0)
130 #define SPIBUSY   (1<<1)
131 #define RXBUSY    (1<<2)
132 #define TXBUSY    (1<<3)
133 
134 struct s3c64xx_spi_dma_data {
135 	unsigned		ch;
136 	enum dma_data_direction direction;
137 	enum dma_ch	dmach;
138 };
139 
140 /**
141  * struct s3c64xx_spi_driver_data - Runtime info holder for SPI driver.
142  * @clk: Pointer to the spi clock.
143  * @src_clk: Pointer to the clock used to generate SPI signals.
144  * @master: Pointer to the SPI Protocol master.
145  * @workqueue: Work queue for the SPI xfer requests.
146  * @cntrlr_info: Platform specific data for the controller this driver manages.
147  * @tgl_spi: Pointer to the last CS left untoggled by the cs_change hint.
148  * @work: Work
149  * @queue: To log SPI xfer requests.
150  * @lock: Controller specific lock.
151  * @state: Set of FLAGS to indicate status.
152  * @rx_dmach: Controller's DMA channel for Rx.
153  * @tx_dmach: Controller's DMA channel for Tx.
154  * @sfr_start: BUS address of SPI controller regs.
155  * @regs: Pointer to ioremap'ed controller registers.
156  * @xfer_completion: To indicate completion of xfer task.
157  * @cur_mode: Stores the active configuration of the controller.
158  * @cur_bpw: Stores the active bits per word settings.
159  * @cur_speed: Stores the active xfer clock speed.
160  */
161 struct s3c64xx_spi_driver_data {
162 	void __iomem                    *regs;
163 	struct clk                      *clk;
164 	struct clk                      *src_clk;
165 	struct platform_device          *pdev;
166 	struct spi_master               *master;
167 	struct workqueue_struct	        *workqueue;
168 	struct s3c64xx_spi_info  *cntrlr_info;
169 	struct spi_device               *tgl_spi;
170 	struct work_struct              work;
171 	struct list_head                queue;
172 	spinlock_t                      lock;
173 	unsigned long                   sfr_start;
174 	struct completion               xfer_completion;
175 	unsigned                        state;
176 	unsigned                        cur_mode, cur_bpw;
177 	unsigned                        cur_speed;
178 	struct s3c64xx_spi_dma_data	rx_dma;
179 	struct s3c64xx_spi_dma_data	tx_dma;
180 	struct samsung_dma_ops		*ops;
181 };
182 
183 static struct s3c2410_dma_client s3c64xx_spi_dma_client = {
184 	.name = "samsung-spi-dma",
185 };
186 
187 static void flush_fifo(struct s3c64xx_spi_driver_data *sdd)
188 {
189 	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
190 	void __iomem *regs = sdd->regs;
191 	unsigned long loops;
192 	u32 val;
193 
194 	writel(0, regs + S3C64XX_SPI_PACKET_CNT);
195 
196 	val = readl(regs + S3C64XX_SPI_CH_CFG);
197 	val |= S3C64XX_SPI_CH_SW_RST;
198 	val &= ~S3C64XX_SPI_CH_HS_EN;
199 	writel(val, regs + S3C64XX_SPI_CH_CFG);
200 
201 	/* Flush TxFIFO*/
202 	loops = msecs_to_loops(1);
203 	do {
204 		val = readl(regs + S3C64XX_SPI_STATUS);
205 	} while (TX_FIFO_LVL(val, sci) && loops--);
206 
207 	if (loops == 0)
208 		dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n");
209 
210 	/* Flush RxFIFO*/
211 	loops = msecs_to_loops(1);
212 	do {
213 		val = readl(regs + S3C64XX_SPI_STATUS);
214 		if (RX_FIFO_LVL(val, sci))
215 			readl(regs + S3C64XX_SPI_RX_DATA);
216 		else
217 			break;
218 	} while (loops--);
219 
220 	if (loops == 0)
221 		dev_warn(&sdd->pdev->dev, "Timed out flushing RX FIFO\n");
222 
223 	val = readl(regs + S3C64XX_SPI_CH_CFG);
224 	val &= ~S3C64XX_SPI_CH_SW_RST;
225 	writel(val, regs + S3C64XX_SPI_CH_CFG);
226 
227 	val = readl(regs + S3C64XX_SPI_MODE_CFG);
228 	val &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
229 	writel(val, regs + S3C64XX_SPI_MODE_CFG);
230 
231 	val = readl(regs + S3C64XX_SPI_CH_CFG);
232 	val &= ~(S3C64XX_SPI_CH_RXCH_ON | S3C64XX_SPI_CH_TXCH_ON);
233 	writel(val, regs + S3C64XX_SPI_CH_CFG);
234 }
235 
236 static void s3c64xx_spi_dmacb(void *data)
237 {
238 	struct s3c64xx_spi_driver_data *sdd;
239 	struct s3c64xx_spi_dma_data *dma = data;
240 	unsigned long flags;
241 
242 	if (dma->direction == DMA_FROM_DEVICE)
243 		sdd = container_of(data,
244 			struct s3c64xx_spi_driver_data, rx_dma);
245 	else
246 		sdd = container_of(data,
247 			struct s3c64xx_spi_driver_data, tx_dma);
248 
249 	spin_lock_irqsave(&sdd->lock, flags);
250 
251 	if (dma->direction == DMA_FROM_DEVICE) {
252 		sdd->state &= ~RXBUSY;
253 		if (!(sdd->state & TXBUSY))
254 			complete(&sdd->xfer_completion);
255 	} else {
256 		sdd->state &= ~TXBUSY;
257 		if (!(sdd->state & RXBUSY))
258 			complete(&sdd->xfer_completion);
259 	}
260 
261 	spin_unlock_irqrestore(&sdd->lock, flags);
262 }
263 
264 static void prepare_dma(struct s3c64xx_spi_dma_data *dma,
265 					unsigned len, dma_addr_t buf)
266 {
267 	struct s3c64xx_spi_driver_data *sdd;
268 	struct samsung_dma_prep_info info;
269 
270 	if (dma->direction == DMA_FROM_DEVICE)
271 		sdd = container_of((void *)dma,
272 			struct s3c64xx_spi_driver_data, rx_dma);
273 	else
274 		sdd = container_of((void *)dma,
275 			struct s3c64xx_spi_driver_data, tx_dma);
276 
277 	info.cap = DMA_SLAVE;
278 	info.len = len;
279 	info.fp = s3c64xx_spi_dmacb;
280 	info.fp_param = dma;
281 	info.direction = dma->direction;
282 	info.buf = buf;
283 
284 	sdd->ops->prepare(dma->ch, &info);
285 	sdd->ops->trigger(dma->ch);
286 }
287 
288 static int acquire_dma(struct s3c64xx_spi_driver_data *sdd)
289 {
290 	struct samsung_dma_info info;
291 
292 	sdd->ops = samsung_dma_get_ops();
293 
294 	info.cap = DMA_SLAVE;
295 	info.client = &s3c64xx_spi_dma_client;
296 	info.width = sdd->cur_bpw / 8;
297 
298 	info.direction = sdd->rx_dma.direction;
299 	info.fifo = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
300 	sdd->rx_dma.ch = sdd->ops->request(sdd->rx_dma.dmach, &info);
301 	info.direction =  sdd->tx_dma.direction;
302 	info.fifo = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
303 	sdd->tx_dma.ch = sdd->ops->request(sdd->tx_dma.dmach, &info);
304 
305 	return 1;
306 }
307 
308 static void enable_datapath(struct s3c64xx_spi_driver_data *sdd,
309 				struct spi_device *spi,
310 				struct spi_transfer *xfer, int dma_mode)
311 {
312 	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
313 	void __iomem *regs = sdd->regs;
314 	u32 modecfg, chcfg;
315 
316 	modecfg = readl(regs + S3C64XX_SPI_MODE_CFG);
317 	modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
318 
319 	chcfg = readl(regs + S3C64XX_SPI_CH_CFG);
320 	chcfg &= ~S3C64XX_SPI_CH_TXCH_ON;
321 
322 	if (dma_mode) {
323 		chcfg &= ~S3C64XX_SPI_CH_RXCH_ON;
324 	} else {
325 		/* Always shift in data in FIFO, even if xfer is Tx only,
326 		 * this helps setting PCKT_CNT value for generating clocks
327 		 * as exactly needed.
328 		 */
329 		chcfg |= S3C64XX_SPI_CH_RXCH_ON;
330 		writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
331 					| S3C64XX_SPI_PACKET_CNT_EN,
332 					regs + S3C64XX_SPI_PACKET_CNT);
333 	}
334 
335 	if (xfer->tx_buf != NULL) {
336 		sdd->state |= TXBUSY;
337 		chcfg |= S3C64XX_SPI_CH_TXCH_ON;
338 		if (dma_mode) {
339 			modecfg |= S3C64XX_SPI_MODE_TXDMA_ON;
340 			prepare_dma(&sdd->tx_dma, xfer->len, xfer->tx_dma);
341 		} else {
342 			switch (sdd->cur_bpw) {
343 			case 32:
344 				iowrite32_rep(regs + S3C64XX_SPI_TX_DATA,
345 					xfer->tx_buf, xfer->len / 4);
346 				break;
347 			case 16:
348 				iowrite16_rep(regs + S3C64XX_SPI_TX_DATA,
349 					xfer->tx_buf, xfer->len / 2);
350 				break;
351 			default:
352 				iowrite8_rep(regs + S3C64XX_SPI_TX_DATA,
353 					xfer->tx_buf, xfer->len);
354 				break;
355 			}
356 		}
357 	}
358 
359 	if (xfer->rx_buf != NULL) {
360 		sdd->state |= RXBUSY;
361 
362 		if (sci->high_speed && sdd->cur_speed >= 30000000UL
363 					&& !(sdd->cur_mode & SPI_CPHA))
364 			chcfg |= S3C64XX_SPI_CH_HS_EN;
365 
366 		if (dma_mode) {
367 			modecfg |= S3C64XX_SPI_MODE_RXDMA_ON;
368 			chcfg |= S3C64XX_SPI_CH_RXCH_ON;
369 			writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
370 					| S3C64XX_SPI_PACKET_CNT_EN,
371 					regs + S3C64XX_SPI_PACKET_CNT);
372 			prepare_dma(&sdd->rx_dma, xfer->len, xfer->rx_dma);
373 		}
374 	}
375 
376 	writel(modecfg, regs + S3C64XX_SPI_MODE_CFG);
377 	writel(chcfg, regs + S3C64XX_SPI_CH_CFG);
378 }
379 
380 static inline void enable_cs(struct s3c64xx_spi_driver_data *sdd,
381 						struct spi_device *spi)
382 {
383 	struct s3c64xx_spi_csinfo *cs;
384 
385 	if (sdd->tgl_spi != NULL) { /* If last device toggled after mssg */
386 		if (sdd->tgl_spi != spi) { /* if last mssg on diff device */
387 			/* Deselect the last toggled device */
388 			cs = sdd->tgl_spi->controller_data;
389 			cs->set_level(cs->line,
390 					spi->mode & SPI_CS_HIGH ? 0 : 1);
391 		}
392 		sdd->tgl_spi = NULL;
393 	}
394 
395 	cs = spi->controller_data;
396 	cs->set_level(cs->line, spi->mode & SPI_CS_HIGH ? 1 : 0);
397 }
398 
399 static int wait_for_xfer(struct s3c64xx_spi_driver_data *sdd,
400 				struct spi_transfer *xfer, int dma_mode)
401 {
402 	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
403 	void __iomem *regs = sdd->regs;
404 	unsigned long val;
405 	int ms;
406 
407 	/* millisecs to xfer 'len' bytes @ 'cur_speed' */
408 	ms = xfer->len * 8 * 1000 / sdd->cur_speed;
409 	ms += 10; /* some tolerance */
410 
411 	if (dma_mode) {
412 		val = msecs_to_jiffies(ms) + 10;
413 		val = wait_for_completion_timeout(&sdd->xfer_completion, val);
414 	} else {
415 		u32 status;
416 		val = msecs_to_loops(ms);
417 		do {
418 			status = readl(regs + S3C64XX_SPI_STATUS);
419 		} while (RX_FIFO_LVL(status, sci) < xfer->len && --val);
420 	}
421 
422 	if (!val)
423 		return -EIO;
424 
425 	if (dma_mode) {
426 		u32 status;
427 
428 		/*
429 		 * DmaTx returns after simply writing data in the FIFO,
430 		 * w/o waiting for real transmission on the bus to finish.
431 		 * DmaRx returns only after Dma read data from FIFO which
432 		 * needs bus transmission to finish, so we don't worry if
433 		 * Xfer involved Rx(with or without Tx).
434 		 */
435 		if (xfer->rx_buf == NULL) {
436 			val = msecs_to_loops(10);
437 			status = readl(regs + S3C64XX_SPI_STATUS);
438 			while ((TX_FIFO_LVL(status, sci)
439 				|| !S3C64XX_SPI_ST_TX_DONE(status, sci))
440 					&& --val) {
441 				cpu_relax();
442 				status = readl(regs + S3C64XX_SPI_STATUS);
443 			}
444 
445 			if (!val)
446 				return -EIO;
447 		}
448 	} else {
449 		/* If it was only Tx */
450 		if (xfer->rx_buf == NULL) {
451 			sdd->state &= ~TXBUSY;
452 			return 0;
453 		}
454 
455 		switch (sdd->cur_bpw) {
456 		case 32:
457 			ioread32_rep(regs + S3C64XX_SPI_RX_DATA,
458 				xfer->rx_buf, xfer->len / 4);
459 			break;
460 		case 16:
461 			ioread16_rep(regs + S3C64XX_SPI_RX_DATA,
462 				xfer->rx_buf, xfer->len / 2);
463 			break;
464 		default:
465 			ioread8_rep(regs + S3C64XX_SPI_RX_DATA,
466 				xfer->rx_buf, xfer->len);
467 			break;
468 		}
469 		sdd->state &= ~RXBUSY;
470 	}
471 
472 	return 0;
473 }
474 
475 static inline void disable_cs(struct s3c64xx_spi_driver_data *sdd,
476 						struct spi_device *spi)
477 {
478 	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
479 
480 	if (sdd->tgl_spi == spi)
481 		sdd->tgl_spi = NULL;
482 
483 	cs->set_level(cs->line, spi->mode & SPI_CS_HIGH ? 0 : 1);
484 }
485 
486 static void s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
487 {
488 	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
489 	void __iomem *regs = sdd->regs;
490 	u32 val;
491 
492 	/* Disable Clock */
493 	if (sci->clk_from_cmu) {
494 		clk_disable(sdd->src_clk);
495 	} else {
496 		val = readl(regs + S3C64XX_SPI_CLK_CFG);
497 		val &= ~S3C64XX_SPI_ENCLK_ENABLE;
498 		writel(val, regs + S3C64XX_SPI_CLK_CFG);
499 	}
500 
501 	/* Set Polarity and Phase */
502 	val = readl(regs + S3C64XX_SPI_CH_CFG);
503 	val &= ~(S3C64XX_SPI_CH_SLAVE |
504 			S3C64XX_SPI_CPOL_L |
505 			S3C64XX_SPI_CPHA_B);
506 
507 	if (sdd->cur_mode & SPI_CPOL)
508 		val |= S3C64XX_SPI_CPOL_L;
509 
510 	if (sdd->cur_mode & SPI_CPHA)
511 		val |= S3C64XX_SPI_CPHA_B;
512 
513 	writel(val, regs + S3C64XX_SPI_CH_CFG);
514 
515 	/* Set Channel & DMA Mode */
516 	val = readl(regs + S3C64XX_SPI_MODE_CFG);
517 	val &= ~(S3C64XX_SPI_MODE_BUS_TSZ_MASK
518 			| S3C64XX_SPI_MODE_CH_TSZ_MASK);
519 
520 	switch (sdd->cur_bpw) {
521 	case 32:
522 		val |= S3C64XX_SPI_MODE_BUS_TSZ_WORD;
523 		val |= S3C64XX_SPI_MODE_CH_TSZ_WORD;
524 		break;
525 	case 16:
526 		val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD;
527 		val |= S3C64XX_SPI_MODE_CH_TSZ_HALFWORD;
528 		break;
529 	default:
530 		val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE;
531 		val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE;
532 		break;
533 	}
534 
535 	writel(val, regs + S3C64XX_SPI_MODE_CFG);
536 
537 	if (sci->clk_from_cmu) {
538 		/* Configure Clock */
539 		/* There is half-multiplier before the SPI */
540 		clk_set_rate(sdd->src_clk, sdd->cur_speed * 2);
541 		/* Enable Clock */
542 		clk_enable(sdd->src_clk);
543 	} else {
544 		/* Configure Clock */
545 		val = readl(regs + S3C64XX_SPI_CLK_CFG);
546 		val &= ~S3C64XX_SPI_PSR_MASK;
547 		val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / 2 - 1)
548 				& S3C64XX_SPI_PSR_MASK);
549 		writel(val, regs + S3C64XX_SPI_CLK_CFG);
550 
551 		/* Enable Clock */
552 		val = readl(regs + S3C64XX_SPI_CLK_CFG);
553 		val |= S3C64XX_SPI_ENCLK_ENABLE;
554 		writel(val, regs + S3C64XX_SPI_CLK_CFG);
555 	}
556 }
557 
558 #define XFER_DMAADDR_INVALID DMA_BIT_MASK(32)
559 
560 static int s3c64xx_spi_map_mssg(struct s3c64xx_spi_driver_data *sdd,
561 						struct spi_message *msg)
562 {
563 	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
564 	struct device *dev = &sdd->pdev->dev;
565 	struct spi_transfer *xfer;
566 
567 	if (msg->is_dma_mapped)
568 		return 0;
569 
570 	/* First mark all xfer unmapped */
571 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
572 		xfer->rx_dma = XFER_DMAADDR_INVALID;
573 		xfer->tx_dma = XFER_DMAADDR_INVALID;
574 	}
575 
576 	/* Map until end or first fail */
577 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
578 
579 		if (xfer->len <= ((sci->fifo_lvl_mask >> 1) + 1))
580 			continue;
581 
582 		if (xfer->tx_buf != NULL) {
583 			xfer->tx_dma = dma_map_single(dev,
584 					(void *)xfer->tx_buf, xfer->len,
585 					DMA_TO_DEVICE);
586 			if (dma_mapping_error(dev, xfer->tx_dma)) {
587 				dev_err(dev, "dma_map_single Tx failed\n");
588 				xfer->tx_dma = XFER_DMAADDR_INVALID;
589 				return -ENOMEM;
590 			}
591 		}
592 
593 		if (xfer->rx_buf != NULL) {
594 			xfer->rx_dma = dma_map_single(dev, xfer->rx_buf,
595 						xfer->len, DMA_FROM_DEVICE);
596 			if (dma_mapping_error(dev, xfer->rx_dma)) {
597 				dev_err(dev, "dma_map_single Rx failed\n");
598 				dma_unmap_single(dev, xfer->tx_dma,
599 						xfer->len, DMA_TO_DEVICE);
600 				xfer->tx_dma = XFER_DMAADDR_INVALID;
601 				xfer->rx_dma = XFER_DMAADDR_INVALID;
602 				return -ENOMEM;
603 			}
604 		}
605 	}
606 
607 	return 0;
608 }
609 
610 static void s3c64xx_spi_unmap_mssg(struct s3c64xx_spi_driver_data *sdd,
611 						struct spi_message *msg)
612 {
613 	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
614 	struct device *dev = &sdd->pdev->dev;
615 	struct spi_transfer *xfer;
616 
617 	if (msg->is_dma_mapped)
618 		return;
619 
620 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
621 
622 		if (xfer->len <= ((sci->fifo_lvl_mask >> 1) + 1))
623 			continue;
624 
625 		if (xfer->rx_buf != NULL
626 				&& xfer->rx_dma != XFER_DMAADDR_INVALID)
627 			dma_unmap_single(dev, xfer->rx_dma,
628 						xfer->len, DMA_FROM_DEVICE);
629 
630 		if (xfer->tx_buf != NULL
631 				&& xfer->tx_dma != XFER_DMAADDR_INVALID)
632 			dma_unmap_single(dev, xfer->tx_dma,
633 						xfer->len, DMA_TO_DEVICE);
634 	}
635 }
636 
637 static void handle_msg(struct s3c64xx_spi_driver_data *sdd,
638 					struct spi_message *msg)
639 {
640 	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
641 	struct spi_device *spi = msg->spi;
642 	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
643 	struct spi_transfer *xfer;
644 	int status = 0, cs_toggle = 0;
645 	u32 speed;
646 	u8 bpw;
647 
648 	/* If Master's(controller) state differs from that needed by Slave */
649 	if (sdd->cur_speed != spi->max_speed_hz
650 			|| sdd->cur_mode != spi->mode
651 			|| sdd->cur_bpw != spi->bits_per_word) {
652 		sdd->cur_bpw = spi->bits_per_word;
653 		sdd->cur_speed = spi->max_speed_hz;
654 		sdd->cur_mode = spi->mode;
655 		s3c64xx_spi_config(sdd);
656 	}
657 
658 	/* Map all the transfers if needed */
659 	if (s3c64xx_spi_map_mssg(sdd, msg)) {
660 		dev_err(&spi->dev,
661 			"Xfer: Unable to map message buffers!\n");
662 		status = -ENOMEM;
663 		goto out;
664 	}
665 
666 	/* Configure feedback delay */
667 	writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK);
668 
669 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
670 
671 		unsigned long flags;
672 		int use_dma;
673 
674 		INIT_COMPLETION(sdd->xfer_completion);
675 
676 		/* Only BPW and Speed may change across transfers */
677 		bpw = xfer->bits_per_word ? : spi->bits_per_word;
678 		speed = xfer->speed_hz ? : spi->max_speed_hz;
679 
680 		if (xfer->len % (bpw / 8)) {
681 			dev_err(&spi->dev,
682 				"Xfer length(%u) not a multiple of word size(%u)\n",
683 				xfer->len, bpw / 8);
684 			status = -EIO;
685 			goto out;
686 		}
687 
688 		if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) {
689 			sdd->cur_bpw = bpw;
690 			sdd->cur_speed = speed;
691 			s3c64xx_spi_config(sdd);
692 		}
693 
694 		/* Polling method for xfers not bigger than FIFO capacity */
695 		if (xfer->len <= ((sci->fifo_lvl_mask >> 1) + 1))
696 			use_dma = 0;
697 		else
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 		/* Slave Select */
709 		enable_cs(sdd, spi);
710 
711 		/* Start the signals */
712 		S3C64XX_SPI_ACT(sdd);
713 
714 		spin_unlock_irqrestore(&sdd->lock, flags);
715 
716 		status = wait_for_xfer(sdd, xfer, use_dma);
717 
718 		/* Quiese the signals */
719 		S3C64XX_SPI_DEACT(sdd);
720 
721 		if (status) {
722 			dev_err(&spi->dev, "I/O Error: "
723 				"rx-%d tx-%d res:rx-%c tx-%c len-%d\n",
724 				xfer->rx_buf ? 1 : 0, xfer->tx_buf ? 1 : 0,
725 				(sdd->state & RXBUSY) ? 'f' : 'p',
726 				(sdd->state & TXBUSY) ? 'f' : 'p',
727 				xfer->len);
728 
729 			if (use_dma) {
730 				if (xfer->tx_buf != NULL
731 						&& (sdd->state & TXBUSY))
732 					sdd->ops->stop(sdd->tx_dma.ch);
733 				if (xfer->rx_buf != NULL
734 						&& (sdd->state & RXBUSY))
735 					sdd->ops->stop(sdd->rx_dma.ch);
736 			}
737 
738 			goto out;
739 		}
740 
741 		if (xfer->delay_usecs)
742 			udelay(xfer->delay_usecs);
743 
744 		if (xfer->cs_change) {
745 			/* Hint that the next mssg is gonna be
746 			   for the same device */
747 			if (list_is_last(&xfer->transfer_list,
748 						&msg->transfers))
749 				cs_toggle = 1;
750 			else
751 				disable_cs(sdd, spi);
752 		}
753 
754 		msg->actual_length += xfer->len;
755 
756 		flush_fifo(sdd);
757 	}
758 
759 out:
760 	if (!cs_toggle || status)
761 		disable_cs(sdd, spi);
762 	else
763 		sdd->tgl_spi = spi;
764 
765 	s3c64xx_spi_unmap_mssg(sdd, msg);
766 
767 	msg->status = status;
768 
769 	if (msg->complete)
770 		msg->complete(msg->context);
771 }
772 
773 static void s3c64xx_spi_work(struct work_struct *work)
774 {
775 	struct s3c64xx_spi_driver_data *sdd = container_of(work,
776 					struct s3c64xx_spi_driver_data, work);
777 	unsigned long flags;
778 
779 	/* Acquire DMA channels */
780 	while (!acquire_dma(sdd))
781 		msleep(10);
782 
783 	spin_lock_irqsave(&sdd->lock, flags);
784 
785 	while (!list_empty(&sdd->queue)
786 				&& !(sdd->state & SUSPND)) {
787 
788 		struct spi_message *msg;
789 
790 		msg = container_of(sdd->queue.next, struct spi_message, queue);
791 
792 		list_del_init(&msg->queue);
793 
794 		/* Set Xfer busy flag */
795 		sdd->state |= SPIBUSY;
796 
797 		spin_unlock_irqrestore(&sdd->lock, flags);
798 
799 		handle_msg(sdd, msg);
800 
801 		spin_lock_irqsave(&sdd->lock, flags);
802 
803 		sdd->state &= ~SPIBUSY;
804 	}
805 
806 	spin_unlock_irqrestore(&sdd->lock, flags);
807 
808 	/* Free DMA channels */
809 	sdd->ops->release(sdd->rx_dma.ch, &s3c64xx_spi_dma_client);
810 	sdd->ops->release(sdd->tx_dma.ch, &s3c64xx_spi_dma_client);
811 }
812 
813 static int s3c64xx_spi_transfer(struct spi_device *spi,
814 						struct spi_message *msg)
815 {
816 	struct s3c64xx_spi_driver_data *sdd;
817 	unsigned long flags;
818 
819 	sdd = spi_master_get_devdata(spi->master);
820 
821 	spin_lock_irqsave(&sdd->lock, flags);
822 
823 	if (sdd->state & SUSPND) {
824 		spin_unlock_irqrestore(&sdd->lock, flags);
825 		return -ESHUTDOWN;
826 	}
827 
828 	msg->status = -EINPROGRESS;
829 	msg->actual_length = 0;
830 
831 	list_add_tail(&msg->queue, &sdd->queue);
832 
833 	queue_work(sdd->workqueue, &sdd->work);
834 
835 	spin_unlock_irqrestore(&sdd->lock, flags);
836 
837 	return 0;
838 }
839 
840 /*
841  * Here we only check the validity of requested configuration
842  * and save the configuration in a local data-structure.
843  * The controller is actually configured only just before we
844  * get a message to transfer.
845  */
846 static int s3c64xx_spi_setup(struct spi_device *spi)
847 {
848 	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
849 	struct s3c64xx_spi_driver_data *sdd;
850 	struct s3c64xx_spi_info *sci;
851 	struct spi_message *msg;
852 	unsigned long flags;
853 	int err = 0;
854 
855 	if (cs == NULL || cs->set_level == NULL) {
856 		dev_err(&spi->dev, "No CS for SPI(%d)\n", spi->chip_select);
857 		return -ENODEV;
858 	}
859 
860 	sdd = spi_master_get_devdata(spi->master);
861 	sci = sdd->cntrlr_info;
862 
863 	spin_lock_irqsave(&sdd->lock, flags);
864 
865 	list_for_each_entry(msg, &sdd->queue, queue) {
866 		/* Is some mssg is already queued for this device */
867 		if (msg->spi == spi) {
868 			dev_err(&spi->dev,
869 				"setup: attempt while mssg in queue!\n");
870 			spin_unlock_irqrestore(&sdd->lock, flags);
871 			return -EBUSY;
872 		}
873 	}
874 
875 	if (sdd->state & SUSPND) {
876 		spin_unlock_irqrestore(&sdd->lock, flags);
877 		dev_err(&spi->dev,
878 			"setup: SPI-%d not active!\n", spi->master->bus_num);
879 		return -ESHUTDOWN;
880 	}
881 
882 	spin_unlock_irqrestore(&sdd->lock, flags);
883 
884 	if (spi->bits_per_word != 8
885 			&& spi->bits_per_word != 16
886 			&& spi->bits_per_word != 32) {
887 		dev_err(&spi->dev, "setup: %dbits/wrd not supported!\n",
888 							spi->bits_per_word);
889 		err = -EINVAL;
890 		goto setup_exit;
891 	}
892 
893 	/* Check if we can provide the requested rate */
894 	if (!sci->clk_from_cmu) {
895 		u32 psr, speed;
896 
897 		/* Max possible */
898 		speed = clk_get_rate(sdd->src_clk) / 2 / (0 + 1);
899 
900 		if (spi->max_speed_hz > speed)
901 			spi->max_speed_hz = speed;
902 
903 		psr = clk_get_rate(sdd->src_clk) / 2 / spi->max_speed_hz - 1;
904 		psr &= S3C64XX_SPI_PSR_MASK;
905 		if (psr == S3C64XX_SPI_PSR_MASK)
906 			psr--;
907 
908 		speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
909 		if (spi->max_speed_hz < speed) {
910 			if (psr+1 < S3C64XX_SPI_PSR_MASK) {
911 				psr++;
912 			} else {
913 				err = -EINVAL;
914 				goto setup_exit;
915 			}
916 		}
917 
918 		speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
919 		if (spi->max_speed_hz >= speed)
920 			spi->max_speed_hz = speed;
921 		else
922 			err = -EINVAL;
923 	}
924 
925 setup_exit:
926 
927 	/* setup() returns with device de-selected */
928 	disable_cs(sdd, spi);
929 
930 	return err;
931 }
932 
933 static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd, int channel)
934 {
935 	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
936 	void __iomem *regs = sdd->regs;
937 	unsigned int val;
938 
939 	sdd->cur_speed = 0;
940 
941 	S3C64XX_SPI_DEACT(sdd);
942 
943 	/* Disable Interrupts - we use Polling if not DMA mode */
944 	writel(0, regs + S3C64XX_SPI_INT_EN);
945 
946 	if (!sci->clk_from_cmu)
947 		writel(sci->src_clk_nr << S3C64XX_SPI_CLKSEL_SRCSHFT,
948 				regs + S3C64XX_SPI_CLK_CFG);
949 	writel(0, regs + S3C64XX_SPI_MODE_CFG);
950 	writel(0, regs + S3C64XX_SPI_PACKET_CNT);
951 
952 	/* Clear any irq pending bits */
953 	writel(readl(regs + S3C64XX_SPI_PENDING_CLR),
954 				regs + S3C64XX_SPI_PENDING_CLR);
955 
956 	writel(0, regs + S3C64XX_SPI_SWAP_CFG);
957 
958 	val = readl(regs + S3C64XX_SPI_MODE_CFG);
959 	val &= ~S3C64XX_SPI_MODE_4BURST;
960 	val &= ~(S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
961 	val |= (S3C64XX_SPI_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
962 	writel(val, regs + S3C64XX_SPI_MODE_CFG);
963 
964 	flush_fifo(sdd);
965 }
966 
967 static int __init s3c64xx_spi_probe(struct platform_device *pdev)
968 {
969 	struct resource	*mem_res, *dmatx_res, *dmarx_res;
970 	struct s3c64xx_spi_driver_data *sdd;
971 	struct s3c64xx_spi_info *sci;
972 	struct spi_master *master;
973 	int ret;
974 	char clk_name[16];
975 
976 	if (pdev->id < 0) {
977 		dev_err(&pdev->dev,
978 				"Invalid platform device id-%d\n", pdev->id);
979 		return -ENODEV;
980 	}
981 
982 	if (pdev->dev.platform_data == NULL) {
983 		dev_err(&pdev->dev, "platform_data missing!\n");
984 		return -ENODEV;
985 	}
986 
987 	sci = pdev->dev.platform_data;
988 
989 	/* Check for availability of necessary resource */
990 
991 	dmatx_res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
992 	if (dmatx_res == NULL) {
993 		dev_err(&pdev->dev, "Unable to get SPI-Tx dma resource\n");
994 		return -ENXIO;
995 	}
996 
997 	dmarx_res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
998 	if (dmarx_res == NULL) {
999 		dev_err(&pdev->dev, "Unable to get SPI-Rx dma resource\n");
1000 		return -ENXIO;
1001 	}
1002 
1003 	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1004 	if (mem_res == NULL) {
1005 		dev_err(&pdev->dev, "Unable to get SPI MEM resource\n");
1006 		return -ENXIO;
1007 	}
1008 
1009 	master = spi_alloc_master(&pdev->dev,
1010 				sizeof(struct s3c64xx_spi_driver_data));
1011 	if (master == NULL) {
1012 		dev_err(&pdev->dev, "Unable to allocate SPI Master\n");
1013 		return -ENOMEM;
1014 	}
1015 
1016 	platform_set_drvdata(pdev, master);
1017 
1018 	sdd = spi_master_get_devdata(master);
1019 	sdd->master = master;
1020 	sdd->cntrlr_info = sci;
1021 	sdd->pdev = pdev;
1022 	sdd->sfr_start = mem_res->start;
1023 	sdd->tx_dma.dmach = dmatx_res->start;
1024 	sdd->tx_dma.direction = DMA_TO_DEVICE;
1025 	sdd->rx_dma.dmach = dmarx_res->start;
1026 	sdd->rx_dma.direction = DMA_FROM_DEVICE;
1027 
1028 	sdd->cur_bpw = 8;
1029 
1030 	master->bus_num = pdev->id;
1031 	master->setup = s3c64xx_spi_setup;
1032 	master->transfer = s3c64xx_spi_transfer;
1033 	master->num_chipselect = sci->num_cs;
1034 	master->dma_alignment = 8;
1035 	/* the spi->mode bits understood by this driver: */
1036 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1037 
1038 	if (request_mem_region(mem_res->start,
1039 			resource_size(mem_res), pdev->name) == NULL) {
1040 		dev_err(&pdev->dev, "Req mem region failed\n");
1041 		ret = -ENXIO;
1042 		goto err0;
1043 	}
1044 
1045 	sdd->regs = ioremap(mem_res->start, resource_size(mem_res));
1046 	if (sdd->regs == NULL) {
1047 		dev_err(&pdev->dev, "Unable to remap IO\n");
1048 		ret = -ENXIO;
1049 		goto err1;
1050 	}
1051 
1052 	if (sci->cfg_gpio == NULL || sci->cfg_gpio(pdev)) {
1053 		dev_err(&pdev->dev, "Unable to config gpio\n");
1054 		ret = -EBUSY;
1055 		goto err2;
1056 	}
1057 
1058 	/* Setup clocks */
1059 	sdd->clk = clk_get(&pdev->dev, "spi");
1060 	if (IS_ERR(sdd->clk)) {
1061 		dev_err(&pdev->dev, "Unable to acquire clock 'spi'\n");
1062 		ret = PTR_ERR(sdd->clk);
1063 		goto err3;
1064 	}
1065 
1066 	if (clk_enable(sdd->clk)) {
1067 		dev_err(&pdev->dev, "Couldn't enable clock 'spi'\n");
1068 		ret = -EBUSY;
1069 		goto err4;
1070 	}
1071 
1072 	sprintf(clk_name, "spi_busclk%d", sci->src_clk_nr);
1073 	sdd->src_clk = clk_get(&pdev->dev, clk_name);
1074 	if (IS_ERR(sdd->src_clk)) {
1075 		dev_err(&pdev->dev,
1076 			"Unable to acquire clock '%s'\n", clk_name);
1077 		ret = PTR_ERR(sdd->src_clk);
1078 		goto err5;
1079 	}
1080 
1081 	if (clk_enable(sdd->src_clk)) {
1082 		dev_err(&pdev->dev, "Couldn't enable clock '%s'\n", clk_name);
1083 		ret = -EBUSY;
1084 		goto err6;
1085 	}
1086 
1087 	sdd->workqueue = create_singlethread_workqueue(
1088 						dev_name(master->dev.parent));
1089 	if (sdd->workqueue == NULL) {
1090 		dev_err(&pdev->dev, "Unable to create workqueue\n");
1091 		ret = -ENOMEM;
1092 		goto err7;
1093 	}
1094 
1095 	/* Setup Deufult Mode */
1096 	s3c64xx_spi_hwinit(sdd, pdev->id);
1097 
1098 	spin_lock_init(&sdd->lock);
1099 	init_completion(&sdd->xfer_completion);
1100 	INIT_WORK(&sdd->work, s3c64xx_spi_work);
1101 	INIT_LIST_HEAD(&sdd->queue);
1102 
1103 	if (spi_register_master(master)) {
1104 		dev_err(&pdev->dev, "cannot register SPI master\n");
1105 		ret = -EBUSY;
1106 		goto err8;
1107 	}
1108 
1109 	dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d "
1110 					"with %d Slaves attached\n",
1111 					pdev->id, master->num_chipselect);
1112 	dev_dbg(&pdev->dev, "\tIOmem=[0x%x-0x%x]\tDMA=[Rx-%d, Tx-%d]\n",
1113 					mem_res->end, mem_res->start,
1114 					sdd->rx_dma.dmach, sdd->tx_dma.dmach);
1115 
1116 	return 0;
1117 
1118 err8:
1119 	destroy_workqueue(sdd->workqueue);
1120 err7:
1121 	clk_disable(sdd->src_clk);
1122 err6:
1123 	clk_put(sdd->src_clk);
1124 err5:
1125 	clk_disable(sdd->clk);
1126 err4:
1127 	clk_put(sdd->clk);
1128 err3:
1129 err2:
1130 	iounmap((void *) sdd->regs);
1131 err1:
1132 	release_mem_region(mem_res->start, resource_size(mem_res));
1133 err0:
1134 	platform_set_drvdata(pdev, NULL);
1135 	spi_master_put(master);
1136 
1137 	return ret;
1138 }
1139 
1140 static int s3c64xx_spi_remove(struct platform_device *pdev)
1141 {
1142 	struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
1143 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1144 	struct resource	*mem_res;
1145 	unsigned long flags;
1146 
1147 	spin_lock_irqsave(&sdd->lock, flags);
1148 	sdd->state |= SUSPND;
1149 	spin_unlock_irqrestore(&sdd->lock, flags);
1150 
1151 	while (sdd->state & SPIBUSY)
1152 		msleep(10);
1153 
1154 	spi_unregister_master(master);
1155 
1156 	destroy_workqueue(sdd->workqueue);
1157 
1158 	clk_disable(sdd->src_clk);
1159 	clk_put(sdd->src_clk);
1160 
1161 	clk_disable(sdd->clk);
1162 	clk_put(sdd->clk);
1163 
1164 	iounmap((void *) sdd->regs);
1165 
1166 	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1167 	if (mem_res != NULL)
1168 		release_mem_region(mem_res->start, resource_size(mem_res));
1169 
1170 	platform_set_drvdata(pdev, NULL);
1171 	spi_master_put(master);
1172 
1173 	return 0;
1174 }
1175 
1176 #ifdef CONFIG_PM
1177 static int s3c64xx_spi_suspend(struct platform_device *pdev, pm_message_t state)
1178 {
1179 	struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
1180 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1181 	unsigned long flags;
1182 
1183 	spin_lock_irqsave(&sdd->lock, flags);
1184 	sdd->state |= SUSPND;
1185 	spin_unlock_irqrestore(&sdd->lock, flags);
1186 
1187 	while (sdd->state & SPIBUSY)
1188 		msleep(10);
1189 
1190 	/* Disable the clock */
1191 	clk_disable(sdd->src_clk);
1192 	clk_disable(sdd->clk);
1193 
1194 	sdd->cur_speed = 0; /* Output Clock is stopped */
1195 
1196 	return 0;
1197 }
1198 
1199 static int s3c64xx_spi_resume(struct platform_device *pdev)
1200 {
1201 	struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
1202 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1203 	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1204 	unsigned long flags;
1205 
1206 	sci->cfg_gpio(pdev);
1207 
1208 	/* Enable the clock */
1209 	clk_enable(sdd->src_clk);
1210 	clk_enable(sdd->clk);
1211 
1212 	s3c64xx_spi_hwinit(sdd, pdev->id);
1213 
1214 	spin_lock_irqsave(&sdd->lock, flags);
1215 	sdd->state &= ~SUSPND;
1216 	spin_unlock_irqrestore(&sdd->lock, flags);
1217 
1218 	return 0;
1219 }
1220 #else
1221 #define s3c64xx_spi_suspend	NULL
1222 #define s3c64xx_spi_resume	NULL
1223 #endif /* CONFIG_PM */
1224 
1225 static struct platform_driver s3c64xx_spi_driver = {
1226 	.driver = {
1227 		.name	= "s3c64xx-spi",
1228 		.owner = THIS_MODULE,
1229 	},
1230 	.remove = s3c64xx_spi_remove,
1231 	.suspend = s3c64xx_spi_suspend,
1232 	.resume = s3c64xx_spi_resume,
1233 };
1234 MODULE_ALIAS("platform:s3c64xx-spi");
1235 
1236 static int __init s3c64xx_spi_init(void)
1237 {
1238 	return platform_driver_probe(&s3c64xx_spi_driver, s3c64xx_spi_probe);
1239 }
1240 subsys_initcall(s3c64xx_spi_init);
1241 
1242 static void __exit s3c64xx_spi_exit(void)
1243 {
1244 	platform_driver_unregister(&s3c64xx_spi_driver);
1245 }
1246 module_exit(s3c64xx_spi_exit);
1247 
1248 MODULE_AUTHOR("Jaswinder Singh <jassi.brar@samsung.com>");
1249 MODULE_DESCRIPTION("S3C64XX SPI Controller Driver");
1250 MODULE_LICENSE("GPL");
1251