xref: /openbmc/linux/drivers/spi/spi-s3c64xx.c (revision 97da55fc)
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 };
138 
139 /**
140  * struct s3c64xx_spi_info - SPI Controller hardware info
141  * @fifo_lvl_mask: Bit-mask for {TX|RX}_FIFO_LVL bits in SPI_STATUS register.
142  * @rx_lvl_offset: Bit offset of RX_FIFO_LVL bits in SPI_STATUS regiter.
143  * @tx_st_done: Bit offset of TX_DONE bit in SPI_STATUS regiter.
144  * @high_speed: True, if the controller supports HIGH_SPEED_EN bit.
145  * @clk_from_cmu: True, if the controller does not include a clock mux and
146  *	prescaler unit.
147  *
148  * The Samsung s3c64xx SPI controller are used on various Samsung SoC's but
149  * differ in some aspects such as the size of the fifo and spi bus clock
150  * setup. Such differences are specified to the driver using this structure
151  * which is provided as driver data to the driver.
152  */
153 struct s3c64xx_spi_port_config {
154 	int	fifo_lvl_mask[MAX_SPI_PORTS];
155 	int	rx_lvl_offset;
156 	int	tx_st_done;
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  * @queue: To log SPI xfer requests.
169  * @lock: Controller specific lock.
170  * @state: Set of FLAGS to indicate status.
171  * @rx_dmach: Controller's DMA channel for Rx.
172  * @tx_dmach: Controller's DMA channel for Tx.
173  * @sfr_start: BUS address of SPI controller regs.
174  * @regs: Pointer to ioremap'ed controller registers.
175  * @irq: interrupt
176  * @xfer_completion: To indicate completion of xfer task.
177  * @cur_mode: Stores the active configuration of the controller.
178  * @cur_bpw: Stores the active bits per word settings.
179  * @cur_speed: Stores the active xfer clock speed.
180  */
181 struct s3c64xx_spi_driver_data {
182 	void __iomem                    *regs;
183 	struct clk                      *clk;
184 	struct clk                      *src_clk;
185 	struct platform_device          *pdev;
186 	struct spi_master               *master;
187 	struct s3c64xx_spi_info  *cntrlr_info;
188 	struct spi_device               *tgl_spi;
189 	struct list_head                queue;
190 	spinlock_t                      lock;
191 	unsigned long                   sfr_start;
192 	struct completion               xfer_completion;
193 	unsigned                        state;
194 	unsigned                        cur_mode, cur_bpw;
195 	unsigned                        cur_speed;
196 	struct s3c64xx_spi_dma_data	rx_dma;
197 	struct s3c64xx_spi_dma_data	tx_dma;
198 	struct samsung_dma_ops		*ops;
199 	struct s3c64xx_spi_port_config	*port_conf;
200 	unsigned int			port_id;
201 	unsigned long			gpios[4];
202 };
203 
204 static struct s3c2410_dma_client s3c64xx_spi_dma_client = {
205 	.name = "samsung-spi-dma",
206 };
207 
208 static void flush_fifo(struct s3c64xx_spi_driver_data *sdd)
209 {
210 	void __iomem *regs = sdd->regs;
211 	unsigned long loops;
212 	u32 val;
213 
214 	writel(0, regs + S3C64XX_SPI_PACKET_CNT);
215 
216 	val = readl(regs + S3C64XX_SPI_CH_CFG);
217 	val &= ~(S3C64XX_SPI_CH_RXCH_ON | S3C64XX_SPI_CH_TXCH_ON);
218 	writel(val, regs + S3C64XX_SPI_CH_CFG);
219 
220 	val = readl(regs + S3C64XX_SPI_CH_CFG);
221 	val |= S3C64XX_SPI_CH_SW_RST;
222 	val &= ~S3C64XX_SPI_CH_HS_EN;
223 	writel(val, regs + S3C64XX_SPI_CH_CFG);
224 
225 	/* Flush TxFIFO*/
226 	loops = msecs_to_loops(1);
227 	do {
228 		val = readl(regs + S3C64XX_SPI_STATUS);
229 	} while (TX_FIFO_LVL(val, sdd) && loops--);
230 
231 	if (loops == 0)
232 		dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n");
233 
234 	/* Flush RxFIFO*/
235 	loops = msecs_to_loops(1);
236 	do {
237 		val = readl(regs + S3C64XX_SPI_STATUS);
238 		if (RX_FIFO_LVL(val, sdd))
239 			readl(regs + S3C64XX_SPI_RX_DATA);
240 		else
241 			break;
242 	} while (loops--);
243 
244 	if (loops == 0)
245 		dev_warn(&sdd->pdev->dev, "Timed out flushing RX FIFO\n");
246 
247 	val = readl(regs + S3C64XX_SPI_CH_CFG);
248 	val &= ~S3C64XX_SPI_CH_SW_RST;
249 	writel(val, regs + S3C64XX_SPI_CH_CFG);
250 
251 	val = readl(regs + S3C64XX_SPI_MODE_CFG);
252 	val &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
253 	writel(val, regs + S3C64XX_SPI_MODE_CFG);
254 }
255 
256 static void s3c64xx_spi_dmacb(void *data)
257 {
258 	struct s3c64xx_spi_driver_data *sdd;
259 	struct s3c64xx_spi_dma_data *dma = data;
260 	unsigned long flags;
261 
262 	if (dma->direction == DMA_DEV_TO_MEM)
263 		sdd = container_of(data,
264 			struct s3c64xx_spi_driver_data, rx_dma);
265 	else
266 		sdd = container_of(data,
267 			struct s3c64xx_spi_driver_data, tx_dma);
268 
269 	spin_lock_irqsave(&sdd->lock, flags);
270 
271 	if (dma->direction == DMA_DEV_TO_MEM) {
272 		sdd->state &= ~RXBUSY;
273 		if (!(sdd->state & TXBUSY))
274 			complete(&sdd->xfer_completion);
275 	} else {
276 		sdd->state &= ~TXBUSY;
277 		if (!(sdd->state & RXBUSY))
278 			complete(&sdd->xfer_completion);
279 	}
280 
281 	spin_unlock_irqrestore(&sdd->lock, flags);
282 }
283 
284 static void prepare_dma(struct s3c64xx_spi_dma_data *dma,
285 					unsigned len, dma_addr_t buf)
286 {
287 	struct s3c64xx_spi_driver_data *sdd;
288 	struct samsung_dma_prep info;
289 	struct samsung_dma_config config;
290 
291 	if (dma->direction == DMA_DEV_TO_MEM) {
292 		sdd = container_of((void *)dma,
293 			struct s3c64xx_spi_driver_data, rx_dma);
294 		config.direction = sdd->rx_dma.direction;
295 		config.fifo = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
296 		config.width = sdd->cur_bpw / 8;
297 		sdd->ops->config(sdd->rx_dma.ch, &config);
298 	} else {
299 		sdd = container_of((void *)dma,
300 			struct s3c64xx_spi_driver_data, tx_dma);
301 		config.direction =  sdd->tx_dma.direction;
302 		config.fifo = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
303 		config.width = sdd->cur_bpw / 8;
304 		sdd->ops->config(sdd->tx_dma.ch, &config);
305 	}
306 
307 	info.cap = DMA_SLAVE;
308 	info.len = len;
309 	info.fp = s3c64xx_spi_dmacb;
310 	info.fp_param = dma;
311 	info.direction = dma->direction;
312 	info.buf = buf;
313 
314 	sdd->ops->prepare(dma->ch, &info);
315 	sdd->ops->trigger(dma->ch);
316 }
317 
318 static int acquire_dma(struct s3c64xx_spi_driver_data *sdd)
319 {
320 	struct samsung_dma_req req;
321 	struct device *dev = &sdd->pdev->dev;
322 
323 	sdd->ops = samsung_dma_get_ops();
324 
325 	req.cap = DMA_SLAVE;
326 	req.client = &s3c64xx_spi_dma_client;
327 
328 	sdd->rx_dma.ch = sdd->ops->request(sdd->rx_dma.dmach, &req, dev, "rx");
329 	sdd->tx_dma.ch = sdd->ops->request(sdd->tx_dma.dmach, &req, dev, "tx");
330 
331 	return 1;
332 }
333 
334 static void enable_datapath(struct s3c64xx_spi_driver_data *sdd,
335 				struct spi_device *spi,
336 				struct spi_transfer *xfer, int dma_mode)
337 {
338 	void __iomem *regs = sdd->regs;
339 	u32 modecfg, chcfg;
340 
341 	modecfg = readl(regs + S3C64XX_SPI_MODE_CFG);
342 	modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
343 
344 	chcfg = readl(regs + S3C64XX_SPI_CH_CFG);
345 	chcfg &= ~S3C64XX_SPI_CH_TXCH_ON;
346 
347 	if (dma_mode) {
348 		chcfg &= ~S3C64XX_SPI_CH_RXCH_ON;
349 	} else {
350 		/* Always shift in data in FIFO, even if xfer is Tx only,
351 		 * this helps setting PCKT_CNT value for generating clocks
352 		 * as exactly needed.
353 		 */
354 		chcfg |= S3C64XX_SPI_CH_RXCH_ON;
355 		writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
356 					| S3C64XX_SPI_PACKET_CNT_EN,
357 					regs + S3C64XX_SPI_PACKET_CNT);
358 	}
359 
360 	if (xfer->tx_buf != NULL) {
361 		sdd->state |= TXBUSY;
362 		chcfg |= S3C64XX_SPI_CH_TXCH_ON;
363 		if (dma_mode) {
364 			modecfg |= S3C64XX_SPI_MODE_TXDMA_ON;
365 			prepare_dma(&sdd->tx_dma, xfer->len, xfer->tx_dma);
366 		} else {
367 			switch (sdd->cur_bpw) {
368 			case 32:
369 				iowrite32_rep(regs + S3C64XX_SPI_TX_DATA,
370 					xfer->tx_buf, xfer->len / 4);
371 				break;
372 			case 16:
373 				iowrite16_rep(regs + S3C64XX_SPI_TX_DATA,
374 					xfer->tx_buf, xfer->len / 2);
375 				break;
376 			default:
377 				iowrite8_rep(regs + S3C64XX_SPI_TX_DATA,
378 					xfer->tx_buf, xfer->len);
379 				break;
380 			}
381 		}
382 	}
383 
384 	if (xfer->rx_buf != NULL) {
385 		sdd->state |= RXBUSY;
386 
387 		if (sdd->port_conf->high_speed && sdd->cur_speed >= 30000000UL
388 					&& !(sdd->cur_mode & SPI_CPHA))
389 			chcfg |= S3C64XX_SPI_CH_HS_EN;
390 
391 		if (dma_mode) {
392 			modecfg |= S3C64XX_SPI_MODE_RXDMA_ON;
393 			chcfg |= S3C64XX_SPI_CH_RXCH_ON;
394 			writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
395 					| S3C64XX_SPI_PACKET_CNT_EN,
396 					regs + S3C64XX_SPI_PACKET_CNT);
397 			prepare_dma(&sdd->rx_dma, xfer->len, xfer->rx_dma);
398 		}
399 	}
400 
401 	writel(modecfg, regs + S3C64XX_SPI_MODE_CFG);
402 	writel(chcfg, regs + S3C64XX_SPI_CH_CFG);
403 }
404 
405 static inline void enable_cs(struct s3c64xx_spi_driver_data *sdd,
406 						struct spi_device *spi)
407 {
408 	struct s3c64xx_spi_csinfo *cs;
409 
410 	if (sdd->tgl_spi != NULL) { /* If last device toggled after mssg */
411 		if (sdd->tgl_spi != spi) { /* if last mssg on diff device */
412 			/* Deselect the last toggled device */
413 			cs = sdd->tgl_spi->controller_data;
414 			gpio_set_value(cs->line,
415 				spi->mode & SPI_CS_HIGH ? 0 : 1);
416 		}
417 		sdd->tgl_spi = NULL;
418 	}
419 
420 	cs = spi->controller_data;
421 	gpio_set_value(cs->line, spi->mode & SPI_CS_HIGH ? 1 : 0);
422 }
423 
424 static int wait_for_xfer(struct s3c64xx_spi_driver_data *sdd,
425 				struct spi_transfer *xfer, int dma_mode)
426 {
427 	void __iomem *regs = sdd->regs;
428 	unsigned long val;
429 	int ms;
430 
431 	/* millisecs to xfer 'len' bytes @ 'cur_speed' */
432 	ms = xfer->len * 8 * 1000 / sdd->cur_speed;
433 	ms += 10; /* some tolerance */
434 
435 	if (dma_mode) {
436 		val = msecs_to_jiffies(ms) + 10;
437 		val = wait_for_completion_timeout(&sdd->xfer_completion, val);
438 	} else {
439 		u32 status;
440 		val = msecs_to_loops(ms);
441 		do {
442 			status = readl(regs + S3C64XX_SPI_STATUS);
443 		} while (RX_FIFO_LVL(status, sdd) < xfer->len && --val);
444 	}
445 
446 	if (!val)
447 		return -EIO;
448 
449 	if (dma_mode) {
450 		u32 status;
451 
452 		/*
453 		 * DmaTx returns after simply writing data in the FIFO,
454 		 * w/o waiting for real transmission on the bus to finish.
455 		 * DmaRx returns only after Dma read data from FIFO which
456 		 * needs bus transmission to finish, so we don't worry if
457 		 * Xfer involved Rx(with or without Tx).
458 		 */
459 		if (xfer->rx_buf == NULL) {
460 			val = msecs_to_loops(10);
461 			status = readl(regs + S3C64XX_SPI_STATUS);
462 			while ((TX_FIFO_LVL(status, sdd)
463 				|| !S3C64XX_SPI_ST_TX_DONE(status, sdd))
464 					&& --val) {
465 				cpu_relax();
466 				status = readl(regs + S3C64XX_SPI_STATUS);
467 			}
468 
469 			if (!val)
470 				return -EIO;
471 		}
472 	} else {
473 		/* If it was only Tx */
474 		if (xfer->rx_buf == NULL) {
475 			sdd->state &= ~TXBUSY;
476 			return 0;
477 		}
478 
479 		switch (sdd->cur_bpw) {
480 		case 32:
481 			ioread32_rep(regs + S3C64XX_SPI_RX_DATA,
482 				xfer->rx_buf, xfer->len / 4);
483 			break;
484 		case 16:
485 			ioread16_rep(regs + S3C64XX_SPI_RX_DATA,
486 				xfer->rx_buf, xfer->len / 2);
487 			break;
488 		default:
489 			ioread8_rep(regs + S3C64XX_SPI_RX_DATA,
490 				xfer->rx_buf, xfer->len);
491 			break;
492 		}
493 		sdd->state &= ~RXBUSY;
494 	}
495 
496 	return 0;
497 }
498 
499 static inline void disable_cs(struct s3c64xx_spi_driver_data *sdd,
500 						struct spi_device *spi)
501 {
502 	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
503 
504 	if (sdd->tgl_spi == spi)
505 		sdd->tgl_spi = NULL;
506 
507 	gpio_set_value(cs->line, spi->mode & SPI_CS_HIGH ? 0 : 1);
508 }
509 
510 static void s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
511 {
512 	void __iomem *regs = sdd->regs;
513 	u32 val;
514 
515 	/* Disable Clock */
516 	if (sdd->port_conf->clk_from_cmu) {
517 		clk_disable_unprepare(sdd->src_clk);
518 	} else {
519 		val = readl(regs + S3C64XX_SPI_CLK_CFG);
520 		val &= ~S3C64XX_SPI_ENCLK_ENABLE;
521 		writel(val, regs + S3C64XX_SPI_CLK_CFG);
522 	}
523 
524 	/* Set Polarity and Phase */
525 	val = readl(regs + S3C64XX_SPI_CH_CFG);
526 	val &= ~(S3C64XX_SPI_CH_SLAVE |
527 			S3C64XX_SPI_CPOL_L |
528 			S3C64XX_SPI_CPHA_B);
529 
530 	if (sdd->cur_mode & SPI_CPOL)
531 		val |= S3C64XX_SPI_CPOL_L;
532 
533 	if (sdd->cur_mode & SPI_CPHA)
534 		val |= S3C64XX_SPI_CPHA_B;
535 
536 	writel(val, regs + S3C64XX_SPI_CH_CFG);
537 
538 	/* Set Channel & DMA Mode */
539 	val = readl(regs + S3C64XX_SPI_MODE_CFG);
540 	val &= ~(S3C64XX_SPI_MODE_BUS_TSZ_MASK
541 			| S3C64XX_SPI_MODE_CH_TSZ_MASK);
542 
543 	switch (sdd->cur_bpw) {
544 	case 32:
545 		val |= S3C64XX_SPI_MODE_BUS_TSZ_WORD;
546 		val |= S3C64XX_SPI_MODE_CH_TSZ_WORD;
547 		break;
548 	case 16:
549 		val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD;
550 		val |= S3C64XX_SPI_MODE_CH_TSZ_HALFWORD;
551 		break;
552 	default:
553 		val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE;
554 		val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE;
555 		break;
556 	}
557 
558 	writel(val, regs + S3C64XX_SPI_MODE_CFG);
559 
560 	if (sdd->port_conf->clk_from_cmu) {
561 		/* Configure Clock */
562 		/* There is half-multiplier before the SPI */
563 		clk_set_rate(sdd->src_clk, sdd->cur_speed * 2);
564 		/* Enable Clock */
565 		clk_prepare_enable(sdd->src_clk);
566 	} else {
567 		/* Configure Clock */
568 		val = readl(regs + S3C64XX_SPI_CLK_CFG);
569 		val &= ~S3C64XX_SPI_PSR_MASK;
570 		val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / 2 - 1)
571 				& S3C64XX_SPI_PSR_MASK);
572 		writel(val, regs + S3C64XX_SPI_CLK_CFG);
573 
574 		/* Enable Clock */
575 		val = readl(regs + S3C64XX_SPI_CLK_CFG);
576 		val |= S3C64XX_SPI_ENCLK_ENABLE;
577 		writel(val, regs + S3C64XX_SPI_CLK_CFG);
578 	}
579 }
580 
581 #define XFER_DMAADDR_INVALID DMA_BIT_MASK(32)
582 
583 static int s3c64xx_spi_map_mssg(struct s3c64xx_spi_driver_data *sdd,
584 						struct spi_message *msg)
585 {
586 	struct device *dev = &sdd->pdev->dev;
587 	struct spi_transfer *xfer;
588 
589 	if (msg->is_dma_mapped)
590 		return 0;
591 
592 	/* First mark all xfer unmapped */
593 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
594 		xfer->rx_dma = XFER_DMAADDR_INVALID;
595 		xfer->tx_dma = XFER_DMAADDR_INVALID;
596 	}
597 
598 	/* Map until end or first fail */
599 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
600 
601 		if (xfer->len <= ((FIFO_LVL_MASK(sdd) >> 1) + 1))
602 			continue;
603 
604 		if (xfer->tx_buf != NULL) {
605 			xfer->tx_dma = dma_map_single(dev,
606 					(void *)xfer->tx_buf, xfer->len,
607 					DMA_TO_DEVICE);
608 			if (dma_mapping_error(dev, xfer->tx_dma)) {
609 				dev_err(dev, "dma_map_single Tx failed\n");
610 				xfer->tx_dma = XFER_DMAADDR_INVALID;
611 				return -ENOMEM;
612 			}
613 		}
614 
615 		if (xfer->rx_buf != NULL) {
616 			xfer->rx_dma = dma_map_single(dev, xfer->rx_buf,
617 						xfer->len, DMA_FROM_DEVICE);
618 			if (dma_mapping_error(dev, xfer->rx_dma)) {
619 				dev_err(dev, "dma_map_single Rx failed\n");
620 				dma_unmap_single(dev, xfer->tx_dma,
621 						xfer->len, DMA_TO_DEVICE);
622 				xfer->tx_dma = XFER_DMAADDR_INVALID;
623 				xfer->rx_dma = XFER_DMAADDR_INVALID;
624 				return -ENOMEM;
625 			}
626 		}
627 	}
628 
629 	return 0;
630 }
631 
632 static void s3c64xx_spi_unmap_mssg(struct s3c64xx_spi_driver_data *sdd,
633 						struct spi_message *msg)
634 {
635 	struct device *dev = &sdd->pdev->dev;
636 	struct spi_transfer *xfer;
637 
638 	if (msg->is_dma_mapped)
639 		return;
640 
641 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
642 
643 		if (xfer->len <= ((FIFO_LVL_MASK(sdd) >> 1) + 1))
644 			continue;
645 
646 		if (xfer->rx_buf != NULL
647 				&& xfer->rx_dma != XFER_DMAADDR_INVALID)
648 			dma_unmap_single(dev, xfer->rx_dma,
649 						xfer->len, DMA_FROM_DEVICE);
650 
651 		if (xfer->tx_buf != NULL
652 				&& xfer->tx_dma != XFER_DMAADDR_INVALID)
653 			dma_unmap_single(dev, xfer->tx_dma,
654 						xfer->len, DMA_TO_DEVICE);
655 	}
656 }
657 
658 static int s3c64xx_spi_transfer_one_message(struct spi_master *master,
659 					    struct spi_message *msg)
660 {
661 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
662 	struct spi_device *spi = msg->spi;
663 	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
664 	struct spi_transfer *xfer;
665 	int status = 0, cs_toggle = 0;
666 	u32 speed;
667 	u8 bpw;
668 
669 	/* If Master's(controller) state differs from that needed by Slave */
670 	if (sdd->cur_speed != spi->max_speed_hz
671 			|| sdd->cur_mode != spi->mode
672 			|| sdd->cur_bpw != spi->bits_per_word) {
673 		sdd->cur_bpw = spi->bits_per_word;
674 		sdd->cur_speed = spi->max_speed_hz;
675 		sdd->cur_mode = spi->mode;
676 		s3c64xx_spi_config(sdd);
677 	}
678 
679 	/* Map all the transfers if needed */
680 	if (s3c64xx_spi_map_mssg(sdd, msg)) {
681 		dev_err(&spi->dev,
682 			"Xfer: Unable to map message buffers!\n");
683 		status = -ENOMEM;
684 		goto out;
685 	}
686 
687 	/* Configure feedback delay */
688 	writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK);
689 
690 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
691 
692 		unsigned long flags;
693 		int use_dma;
694 
695 		INIT_COMPLETION(sdd->xfer_completion);
696 
697 		/* Only BPW and Speed may change across transfers */
698 		bpw = xfer->bits_per_word;
699 		speed = xfer->speed_hz ? : spi->max_speed_hz;
700 
701 		if (xfer->len % (bpw / 8)) {
702 			dev_err(&spi->dev,
703 				"Xfer length(%u) not a multiple of word size(%u)\n",
704 				xfer->len, bpw / 8);
705 			status = -EIO;
706 			goto out;
707 		}
708 
709 		if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) {
710 			sdd->cur_bpw = bpw;
711 			sdd->cur_speed = speed;
712 			s3c64xx_spi_config(sdd);
713 		}
714 
715 		/* Polling method for xfers not bigger than FIFO capacity */
716 		if (xfer->len <= ((FIFO_LVL_MASK(sdd) >> 1) + 1))
717 			use_dma = 0;
718 		else
719 			use_dma = 1;
720 
721 		spin_lock_irqsave(&sdd->lock, flags);
722 
723 		/* Pending only which is to be done */
724 		sdd->state &= ~RXBUSY;
725 		sdd->state &= ~TXBUSY;
726 
727 		enable_datapath(sdd, spi, xfer, use_dma);
728 
729 		/* Slave Select */
730 		enable_cs(sdd, spi);
731 
732 		/* Start the signals */
733 		writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
734 
735 		spin_unlock_irqrestore(&sdd->lock, flags);
736 
737 		status = wait_for_xfer(sdd, xfer, use_dma);
738 
739 		/* Quiese the signals */
740 		writel(S3C64XX_SPI_SLAVE_SIG_INACT,
741 		       sdd->regs + S3C64XX_SPI_SLAVE_SEL);
742 
743 		if (status) {
744 			dev_err(&spi->dev, "I/O Error: rx-%d tx-%d res:rx-%c tx-%c len-%d\n",
745 				xfer->rx_buf ? 1 : 0, xfer->tx_buf ? 1 : 0,
746 				(sdd->state & RXBUSY) ? 'f' : 'p',
747 				(sdd->state & TXBUSY) ? 'f' : 'p',
748 				xfer->len);
749 
750 			if (use_dma) {
751 				if (xfer->tx_buf != NULL
752 						&& (sdd->state & TXBUSY))
753 					sdd->ops->stop(sdd->tx_dma.ch);
754 				if (xfer->rx_buf != NULL
755 						&& (sdd->state & RXBUSY))
756 					sdd->ops->stop(sdd->rx_dma.ch);
757 			}
758 
759 			goto out;
760 		}
761 
762 		if (xfer->delay_usecs)
763 			udelay(xfer->delay_usecs);
764 
765 		if (xfer->cs_change) {
766 			/* Hint that the next mssg is gonna be
767 			   for the same device */
768 			if (list_is_last(&xfer->transfer_list,
769 						&msg->transfers))
770 				cs_toggle = 1;
771 		}
772 
773 		msg->actual_length += xfer->len;
774 
775 		flush_fifo(sdd);
776 	}
777 
778 out:
779 	if (!cs_toggle || status)
780 		disable_cs(sdd, spi);
781 	else
782 		sdd->tgl_spi = spi;
783 
784 	s3c64xx_spi_unmap_mssg(sdd, msg);
785 
786 	msg->status = status;
787 
788 	spi_finalize_current_message(master);
789 
790 	return 0;
791 }
792 
793 static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
794 {
795 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
796 
797 	/* Acquire DMA channels */
798 	while (!acquire_dma(sdd))
799 		usleep_range(10000, 11000);
800 
801 	pm_runtime_get_sync(&sdd->pdev->dev);
802 
803 	return 0;
804 }
805 
806 static int s3c64xx_spi_unprepare_transfer(struct spi_master *spi)
807 {
808 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
809 
810 	/* Free DMA channels */
811 	sdd->ops->release(sdd->rx_dma.ch, &s3c64xx_spi_dma_client);
812 	sdd->ops->release(sdd->tx_dma.ch, &s3c64xx_spi_dma_client);
813 
814 	pm_runtime_put(&sdd->pdev->dev);
815 
816 	return 0;
817 }
818 
819 static struct s3c64xx_spi_csinfo *s3c64xx_get_slave_ctrldata(
820 				struct s3c64xx_spi_driver_data *sdd,
821 				struct spi_device *spi)
822 {
823 	struct s3c64xx_spi_csinfo *cs;
824 	struct device_node *slave_np, *data_np = NULL;
825 	u32 fb_delay = 0;
826 
827 	slave_np = spi->dev.of_node;
828 	if (!slave_np) {
829 		dev_err(&spi->dev, "device node not found\n");
830 		return ERR_PTR(-EINVAL);
831 	}
832 
833 	data_np = of_get_child_by_name(slave_np, "controller-data");
834 	if (!data_np) {
835 		dev_err(&spi->dev, "child node 'controller-data' not found\n");
836 		return ERR_PTR(-EINVAL);
837 	}
838 
839 	cs = kzalloc(sizeof(*cs), GFP_KERNEL);
840 	if (!cs) {
841 		dev_err(&spi->dev, "could not allocate memory for controller data\n");
842 		of_node_put(data_np);
843 		return ERR_PTR(-ENOMEM);
844 	}
845 
846 	cs->line = of_get_named_gpio(data_np, "cs-gpio", 0);
847 	if (!gpio_is_valid(cs->line)) {
848 		dev_err(&spi->dev, "chip select gpio is not specified or invalid\n");
849 		kfree(cs);
850 		of_node_put(data_np);
851 		return ERR_PTR(-EINVAL);
852 	}
853 
854 	of_property_read_u32(data_np, "samsung,spi-feedback-delay", &fb_delay);
855 	cs->fb_delay = fb_delay;
856 	of_node_put(data_np);
857 	return cs;
858 }
859 
860 /*
861  * Here we only check the validity of requested configuration
862  * and save the configuration in a local data-structure.
863  * The controller is actually configured only just before we
864  * get a message to transfer.
865  */
866 static int s3c64xx_spi_setup(struct spi_device *spi)
867 {
868 	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
869 	struct s3c64xx_spi_driver_data *sdd;
870 	struct s3c64xx_spi_info *sci;
871 	struct spi_message *msg;
872 	unsigned long flags;
873 	int err;
874 
875 	sdd = spi_master_get_devdata(spi->master);
876 	if (!cs && spi->dev.of_node) {
877 		cs = s3c64xx_get_slave_ctrldata(sdd, spi);
878 		spi->controller_data = cs;
879 	}
880 
881 	if (IS_ERR_OR_NULL(cs)) {
882 		dev_err(&spi->dev, "No CS for SPI(%d)\n", spi->chip_select);
883 		return -ENODEV;
884 	}
885 
886 	if (!spi_get_ctldata(spi)) {
887 		err = gpio_request_one(cs->line, GPIOF_OUT_INIT_HIGH,
888 				       dev_name(&spi->dev));
889 		if (err) {
890 			dev_err(&spi->dev,
891 				"Failed to get /CS gpio [%d]: %d\n",
892 				cs->line, err);
893 			goto err_gpio_req;
894 		}
895 		spi_set_ctldata(spi, cs);
896 	}
897 
898 	sci = sdd->cntrlr_info;
899 
900 	spin_lock_irqsave(&sdd->lock, flags);
901 
902 	list_for_each_entry(msg, &sdd->queue, queue) {
903 		/* Is some mssg is already queued for this device */
904 		if (msg->spi == spi) {
905 			dev_err(&spi->dev,
906 				"setup: attempt while mssg in queue!\n");
907 			spin_unlock_irqrestore(&sdd->lock, flags);
908 			err = -EBUSY;
909 			goto err_msgq;
910 		}
911 	}
912 
913 	spin_unlock_irqrestore(&sdd->lock, flags);
914 
915 	if (spi->bits_per_word != 8
916 			&& spi->bits_per_word != 16
917 			&& spi->bits_per_word != 32) {
918 		dev_err(&spi->dev, "setup: %dbits/wrd not supported!\n",
919 							spi->bits_per_word);
920 		err = -EINVAL;
921 		goto setup_exit;
922 	}
923 
924 	pm_runtime_get_sync(&sdd->pdev->dev);
925 
926 	/* Check if we can provide the requested rate */
927 	if (!sdd->port_conf->clk_from_cmu) {
928 		u32 psr, speed;
929 
930 		/* Max possible */
931 		speed = clk_get_rate(sdd->src_clk) / 2 / (0 + 1);
932 
933 		if (spi->max_speed_hz > speed)
934 			spi->max_speed_hz = speed;
935 
936 		psr = clk_get_rate(sdd->src_clk) / 2 / spi->max_speed_hz - 1;
937 		psr &= S3C64XX_SPI_PSR_MASK;
938 		if (psr == S3C64XX_SPI_PSR_MASK)
939 			psr--;
940 
941 		speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
942 		if (spi->max_speed_hz < speed) {
943 			if (psr+1 < S3C64XX_SPI_PSR_MASK) {
944 				psr++;
945 			} else {
946 				err = -EINVAL;
947 				goto setup_exit;
948 			}
949 		}
950 
951 		speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
952 		if (spi->max_speed_hz >= speed) {
953 			spi->max_speed_hz = speed;
954 		} else {
955 			dev_err(&spi->dev, "Can't set %dHz transfer speed\n",
956 				spi->max_speed_hz);
957 			err = -EINVAL;
958 			goto setup_exit;
959 		}
960 	}
961 
962 	pm_runtime_put(&sdd->pdev->dev);
963 	disable_cs(sdd, spi);
964 	return 0;
965 
966 setup_exit:
967 	/* setup() returns with device de-selected */
968 	disable_cs(sdd, spi);
969 
970 err_msgq:
971 	gpio_free(cs->line);
972 	spi_set_ctldata(spi, NULL);
973 
974 err_gpio_req:
975 	if (spi->dev.of_node)
976 		kfree(cs);
977 
978 	return err;
979 }
980 
981 static void s3c64xx_spi_cleanup(struct spi_device *spi)
982 {
983 	struct s3c64xx_spi_csinfo *cs = spi_get_ctldata(spi);
984 
985 	if (cs) {
986 		gpio_free(cs->line);
987 		if (spi->dev.of_node)
988 			kfree(cs);
989 	}
990 	spi_set_ctldata(spi, NULL);
991 }
992 
993 static irqreturn_t s3c64xx_spi_irq(int irq, void *data)
994 {
995 	struct s3c64xx_spi_driver_data *sdd = data;
996 	struct spi_master *spi = sdd->master;
997 	unsigned int val;
998 
999 	val = readl(sdd->regs + S3C64XX_SPI_PENDING_CLR);
1000 
1001 	val &= S3C64XX_SPI_PND_RX_OVERRUN_CLR |
1002 		S3C64XX_SPI_PND_RX_UNDERRUN_CLR |
1003 		S3C64XX_SPI_PND_TX_OVERRUN_CLR |
1004 		S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
1005 
1006 	writel(val, sdd->regs + S3C64XX_SPI_PENDING_CLR);
1007 
1008 	if (val & S3C64XX_SPI_PND_RX_OVERRUN_CLR)
1009 		dev_err(&spi->dev, "RX overrun\n");
1010 	if (val & S3C64XX_SPI_PND_RX_UNDERRUN_CLR)
1011 		dev_err(&spi->dev, "RX underrun\n");
1012 	if (val & S3C64XX_SPI_PND_TX_OVERRUN_CLR)
1013 		dev_err(&spi->dev, "TX overrun\n");
1014 	if (val & S3C64XX_SPI_PND_TX_UNDERRUN_CLR)
1015 		dev_err(&spi->dev, "TX underrun\n");
1016 
1017 	return IRQ_HANDLED;
1018 }
1019 
1020 static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd, int channel)
1021 {
1022 	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1023 	void __iomem *regs = sdd->regs;
1024 	unsigned int val;
1025 
1026 	sdd->cur_speed = 0;
1027 
1028 	writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
1029 
1030 	/* Disable Interrupts - we use Polling if not DMA mode */
1031 	writel(0, regs + S3C64XX_SPI_INT_EN);
1032 
1033 	if (!sdd->port_conf->clk_from_cmu)
1034 		writel(sci->src_clk_nr << S3C64XX_SPI_CLKSEL_SRCSHFT,
1035 				regs + S3C64XX_SPI_CLK_CFG);
1036 	writel(0, regs + S3C64XX_SPI_MODE_CFG);
1037 	writel(0, regs + S3C64XX_SPI_PACKET_CNT);
1038 
1039 	/* Clear any irq pending bits */
1040 	writel(readl(regs + S3C64XX_SPI_PENDING_CLR),
1041 				regs + S3C64XX_SPI_PENDING_CLR);
1042 
1043 	writel(0, regs + S3C64XX_SPI_SWAP_CFG);
1044 
1045 	val = readl(regs + S3C64XX_SPI_MODE_CFG);
1046 	val &= ~S3C64XX_SPI_MODE_4BURST;
1047 	val &= ~(S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
1048 	val |= (S3C64XX_SPI_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
1049 	writel(val, regs + S3C64XX_SPI_MODE_CFG);
1050 
1051 	flush_fifo(sdd);
1052 }
1053 
1054 #ifdef CONFIG_OF
1055 static int s3c64xx_spi_parse_dt_gpio(struct s3c64xx_spi_driver_data *sdd)
1056 {
1057 	struct device *dev = &sdd->pdev->dev;
1058 	int idx, gpio, ret;
1059 
1060 	/* find gpios for mosi, miso and clock lines */
1061 	for (idx = 0; idx < 3; idx++) {
1062 		gpio = of_get_gpio(dev->of_node, idx);
1063 		if (!gpio_is_valid(gpio)) {
1064 			dev_err(dev, "invalid gpio[%d]: %d\n", idx, gpio);
1065 			goto free_gpio;
1066 		}
1067 		sdd->gpios[idx] = gpio;
1068 		ret = gpio_request(gpio, "spi-bus");
1069 		if (ret) {
1070 			dev_err(dev, "gpio [%d] request failed: %d\n",
1071 				gpio, ret);
1072 			goto free_gpio;
1073 		}
1074 	}
1075 	return 0;
1076 
1077 free_gpio:
1078 	while (--idx >= 0)
1079 		gpio_free(sdd->gpios[idx]);
1080 	return -EINVAL;
1081 }
1082 
1083 static void s3c64xx_spi_dt_gpio_free(struct s3c64xx_spi_driver_data *sdd)
1084 {
1085 	unsigned int idx;
1086 	for (idx = 0; idx < 3; idx++)
1087 		gpio_free(sdd->gpios[idx]);
1088 }
1089 
1090 static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
1091 {
1092 	struct s3c64xx_spi_info *sci;
1093 	u32 temp;
1094 
1095 	sci = devm_kzalloc(dev, sizeof(*sci), GFP_KERNEL);
1096 	if (!sci) {
1097 		dev_err(dev, "memory allocation for spi_info failed\n");
1098 		return ERR_PTR(-ENOMEM);
1099 	}
1100 
1101 	if (of_property_read_u32(dev->of_node, "samsung,spi-src-clk", &temp)) {
1102 		dev_warn(dev, "spi bus clock parent not specified, using clock at index 0 as parent\n");
1103 		sci->src_clk_nr = 0;
1104 	} else {
1105 		sci->src_clk_nr = temp;
1106 	}
1107 
1108 	if (of_property_read_u32(dev->of_node, "num-cs", &temp)) {
1109 		dev_warn(dev, "number of chip select lines not specified, assuming 1 chip select line\n");
1110 		sci->num_cs = 1;
1111 	} else {
1112 		sci->num_cs = temp;
1113 	}
1114 
1115 	return sci;
1116 }
1117 #else
1118 static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
1119 {
1120 	return dev->platform_data;
1121 }
1122 
1123 static int s3c64xx_spi_parse_dt_gpio(struct s3c64xx_spi_driver_data *sdd)
1124 {
1125 	return -EINVAL;
1126 }
1127 
1128 static void s3c64xx_spi_dt_gpio_free(struct s3c64xx_spi_driver_data *sdd)
1129 {
1130 }
1131 #endif
1132 
1133 static const struct of_device_id s3c64xx_spi_dt_match[];
1134 
1135 static inline struct s3c64xx_spi_port_config *s3c64xx_spi_get_port_config(
1136 						struct platform_device *pdev)
1137 {
1138 #ifdef CONFIG_OF
1139 	if (pdev->dev.of_node) {
1140 		const struct of_device_id *match;
1141 		match = of_match_node(s3c64xx_spi_dt_match, pdev->dev.of_node);
1142 		return (struct s3c64xx_spi_port_config *)match->data;
1143 	}
1144 #endif
1145 	return (struct s3c64xx_spi_port_config *)
1146 			 platform_get_device_id(pdev)->driver_data;
1147 }
1148 
1149 static int s3c64xx_spi_probe(struct platform_device *pdev)
1150 {
1151 	struct resource	*mem_res;
1152 	struct resource	*res;
1153 	struct s3c64xx_spi_driver_data *sdd;
1154 	struct s3c64xx_spi_info *sci = pdev->dev.platform_data;
1155 	struct spi_master *master;
1156 	int ret, irq;
1157 	char clk_name[16];
1158 
1159 	if (!sci && pdev->dev.of_node) {
1160 		sci = s3c64xx_spi_parse_dt(&pdev->dev);
1161 		if (IS_ERR(sci))
1162 			return PTR_ERR(sci);
1163 	}
1164 
1165 	if (!sci) {
1166 		dev_err(&pdev->dev, "platform_data missing!\n");
1167 		return -ENODEV;
1168 	}
1169 
1170 	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1171 	if (mem_res == NULL) {
1172 		dev_err(&pdev->dev, "Unable to get SPI MEM resource\n");
1173 		return -ENXIO;
1174 	}
1175 
1176 	irq = platform_get_irq(pdev, 0);
1177 	if (irq < 0) {
1178 		dev_warn(&pdev->dev, "Failed to get IRQ: %d\n", irq);
1179 		return irq;
1180 	}
1181 
1182 	master = spi_alloc_master(&pdev->dev,
1183 				sizeof(struct s3c64xx_spi_driver_data));
1184 	if (master == NULL) {
1185 		dev_err(&pdev->dev, "Unable to allocate SPI Master\n");
1186 		return -ENOMEM;
1187 	}
1188 
1189 	platform_set_drvdata(pdev, master);
1190 
1191 	sdd = spi_master_get_devdata(master);
1192 	sdd->port_conf = s3c64xx_spi_get_port_config(pdev);
1193 	sdd->master = master;
1194 	sdd->cntrlr_info = sci;
1195 	sdd->pdev = pdev;
1196 	sdd->sfr_start = mem_res->start;
1197 	if (pdev->dev.of_node) {
1198 		ret = of_alias_get_id(pdev->dev.of_node, "spi");
1199 		if (ret < 0) {
1200 			dev_err(&pdev->dev, "failed to get alias id, errno %d\n",
1201 				ret);
1202 			goto err0;
1203 		}
1204 		sdd->port_id = ret;
1205 	} else {
1206 		sdd->port_id = pdev->id;
1207 	}
1208 
1209 	sdd->cur_bpw = 8;
1210 
1211 	if (!sdd->pdev->dev.of_node) {
1212 		res = platform_get_resource(pdev, IORESOURCE_DMA,  0);
1213 		if (!res) {
1214 			dev_err(&pdev->dev, "Unable to get SPI tx dma "
1215 					"resource\n");
1216 			return -ENXIO;
1217 		}
1218 		sdd->tx_dma.dmach = res->start;
1219 
1220 		res = platform_get_resource(pdev, IORESOURCE_DMA,  1);
1221 		if (!res) {
1222 			dev_err(&pdev->dev, "Unable to get SPI rx dma "
1223 					"resource\n");
1224 			return -ENXIO;
1225 		}
1226 		sdd->rx_dma.dmach = res->start;
1227 	}
1228 
1229 	sdd->tx_dma.direction = DMA_MEM_TO_DEV;
1230 	sdd->rx_dma.direction = DMA_DEV_TO_MEM;
1231 
1232 	master->dev.of_node = pdev->dev.of_node;
1233 	master->bus_num = sdd->port_id;
1234 	master->setup = s3c64xx_spi_setup;
1235 	master->cleanup = s3c64xx_spi_cleanup;
1236 	master->prepare_transfer_hardware = s3c64xx_spi_prepare_transfer;
1237 	master->transfer_one_message = s3c64xx_spi_transfer_one_message;
1238 	master->unprepare_transfer_hardware = s3c64xx_spi_unprepare_transfer;
1239 	master->num_chipselect = sci->num_cs;
1240 	master->dma_alignment = 8;
1241 	/* the spi->mode bits understood by this driver: */
1242 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1243 
1244 	sdd->regs = devm_ioremap_resource(&pdev->dev, mem_res);
1245 	if (IS_ERR(sdd->regs)) {
1246 		ret = PTR_ERR(sdd->regs);
1247 		goto err0;
1248 	}
1249 
1250 	if (!sci->cfg_gpio && pdev->dev.of_node) {
1251 		if (s3c64xx_spi_parse_dt_gpio(sdd))
1252 			return -EBUSY;
1253 	} else if (sci->cfg_gpio == NULL || sci->cfg_gpio()) {
1254 		dev_err(&pdev->dev, "Unable to config gpio\n");
1255 		ret = -EBUSY;
1256 		goto err0;
1257 	}
1258 
1259 	/* Setup clocks */
1260 	sdd->clk = devm_clk_get(&pdev->dev, "spi");
1261 	if (IS_ERR(sdd->clk)) {
1262 		dev_err(&pdev->dev, "Unable to acquire clock 'spi'\n");
1263 		ret = PTR_ERR(sdd->clk);
1264 		goto err1;
1265 	}
1266 
1267 	if (clk_prepare_enable(sdd->clk)) {
1268 		dev_err(&pdev->dev, "Couldn't enable clock 'spi'\n");
1269 		ret = -EBUSY;
1270 		goto err1;
1271 	}
1272 
1273 	sprintf(clk_name, "spi_busclk%d", sci->src_clk_nr);
1274 	sdd->src_clk = devm_clk_get(&pdev->dev, clk_name);
1275 	if (IS_ERR(sdd->src_clk)) {
1276 		dev_err(&pdev->dev,
1277 			"Unable to acquire clock '%s'\n", clk_name);
1278 		ret = PTR_ERR(sdd->src_clk);
1279 		goto err2;
1280 	}
1281 
1282 	if (clk_prepare_enable(sdd->src_clk)) {
1283 		dev_err(&pdev->dev, "Couldn't enable clock '%s'\n", clk_name);
1284 		ret = -EBUSY;
1285 		goto err2;
1286 	}
1287 
1288 	/* Setup Deufult Mode */
1289 	s3c64xx_spi_hwinit(sdd, sdd->port_id);
1290 
1291 	spin_lock_init(&sdd->lock);
1292 	init_completion(&sdd->xfer_completion);
1293 	INIT_LIST_HEAD(&sdd->queue);
1294 
1295 	ret = devm_request_irq(&pdev->dev, irq, s3c64xx_spi_irq, 0,
1296 				"spi-s3c64xx", sdd);
1297 	if (ret != 0) {
1298 		dev_err(&pdev->dev, "Failed to request IRQ %d: %d\n",
1299 			irq, ret);
1300 		goto err3;
1301 	}
1302 
1303 	writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
1304 	       S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
1305 	       sdd->regs + S3C64XX_SPI_INT_EN);
1306 
1307 	if (spi_register_master(master)) {
1308 		dev_err(&pdev->dev, "cannot register SPI master\n");
1309 		ret = -EBUSY;
1310 		goto err3;
1311 	}
1312 
1313 	dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d with %d Slaves attached\n",
1314 					sdd->port_id, master->num_chipselect);
1315 	dev_dbg(&pdev->dev, "\tIOmem=[0x%x-0x%x]\tDMA=[Rx-%d, Tx-%d]\n",
1316 					mem_res->end, mem_res->start,
1317 					sdd->rx_dma.dmach, sdd->tx_dma.dmach);
1318 
1319 	pm_runtime_enable(&pdev->dev);
1320 
1321 	return 0;
1322 
1323 err3:
1324 	clk_disable_unprepare(sdd->src_clk);
1325 err2:
1326 	clk_disable_unprepare(sdd->clk);
1327 err1:
1328 	if (!sdd->cntrlr_info->cfg_gpio && pdev->dev.of_node)
1329 		s3c64xx_spi_dt_gpio_free(sdd);
1330 err0:
1331 	platform_set_drvdata(pdev, NULL);
1332 	spi_master_put(master);
1333 
1334 	return ret;
1335 }
1336 
1337 static int s3c64xx_spi_remove(struct platform_device *pdev)
1338 {
1339 	struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
1340 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1341 
1342 	pm_runtime_disable(&pdev->dev);
1343 
1344 	spi_unregister_master(master);
1345 
1346 	writel(0, sdd->regs + S3C64XX_SPI_INT_EN);
1347 
1348 	clk_disable_unprepare(sdd->src_clk);
1349 
1350 	clk_disable_unprepare(sdd->clk);
1351 
1352 	if (!sdd->cntrlr_info->cfg_gpio && pdev->dev.of_node)
1353 		s3c64xx_spi_dt_gpio_free(sdd);
1354 
1355 	platform_set_drvdata(pdev, NULL);
1356 	spi_master_put(master);
1357 
1358 	return 0;
1359 }
1360 
1361 #ifdef CONFIG_PM
1362 static int s3c64xx_spi_suspend(struct device *dev)
1363 {
1364 	struct spi_master *master = dev_get_drvdata(dev);
1365 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1366 
1367 	spi_master_suspend(master);
1368 
1369 	/* Disable the clock */
1370 	clk_disable_unprepare(sdd->src_clk);
1371 	clk_disable_unprepare(sdd->clk);
1372 
1373 	if (!sdd->cntrlr_info->cfg_gpio && dev->of_node)
1374 		s3c64xx_spi_dt_gpio_free(sdd);
1375 
1376 	sdd->cur_speed = 0; /* Output Clock is stopped */
1377 
1378 	return 0;
1379 }
1380 
1381 static int s3c64xx_spi_resume(struct device *dev)
1382 {
1383 	struct spi_master *master = dev_get_drvdata(dev);
1384 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1385 	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1386 
1387 	if (!sci->cfg_gpio && dev->of_node)
1388 		s3c64xx_spi_parse_dt_gpio(sdd);
1389 	else
1390 		sci->cfg_gpio();
1391 
1392 	/* Enable the clock */
1393 	clk_prepare_enable(sdd->src_clk);
1394 	clk_prepare_enable(sdd->clk);
1395 
1396 	s3c64xx_spi_hwinit(sdd, sdd->port_id);
1397 
1398 	spi_master_resume(master);
1399 
1400 	return 0;
1401 }
1402 #endif /* CONFIG_PM */
1403 
1404 #ifdef CONFIG_PM_RUNTIME
1405 static int s3c64xx_spi_runtime_suspend(struct device *dev)
1406 {
1407 	struct spi_master *master = dev_get_drvdata(dev);
1408 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1409 
1410 	clk_disable_unprepare(sdd->clk);
1411 	clk_disable_unprepare(sdd->src_clk);
1412 
1413 	return 0;
1414 }
1415 
1416 static int s3c64xx_spi_runtime_resume(struct device *dev)
1417 {
1418 	struct spi_master *master = dev_get_drvdata(dev);
1419 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1420 
1421 	clk_prepare_enable(sdd->src_clk);
1422 	clk_prepare_enable(sdd->clk);
1423 
1424 	return 0;
1425 }
1426 #endif /* CONFIG_PM_RUNTIME */
1427 
1428 static const struct dev_pm_ops s3c64xx_spi_pm = {
1429 	SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume)
1430 	SET_RUNTIME_PM_OPS(s3c64xx_spi_runtime_suspend,
1431 			   s3c64xx_spi_runtime_resume, NULL)
1432 };
1433 
1434 static struct s3c64xx_spi_port_config s3c2443_spi_port_config = {
1435 	.fifo_lvl_mask	= { 0x7f },
1436 	.rx_lvl_offset	= 13,
1437 	.tx_st_done	= 21,
1438 	.high_speed	= true,
1439 };
1440 
1441 static struct s3c64xx_spi_port_config s3c6410_spi_port_config = {
1442 	.fifo_lvl_mask	= { 0x7f, 0x7F },
1443 	.rx_lvl_offset	= 13,
1444 	.tx_st_done	= 21,
1445 };
1446 
1447 static struct s3c64xx_spi_port_config s5p64x0_spi_port_config = {
1448 	.fifo_lvl_mask	= { 0x1ff, 0x7F },
1449 	.rx_lvl_offset	= 15,
1450 	.tx_st_done	= 25,
1451 };
1452 
1453 static struct s3c64xx_spi_port_config s5pc100_spi_port_config = {
1454 	.fifo_lvl_mask	= { 0x7f, 0x7F },
1455 	.rx_lvl_offset	= 13,
1456 	.tx_st_done	= 21,
1457 	.high_speed	= true,
1458 };
1459 
1460 static struct s3c64xx_spi_port_config s5pv210_spi_port_config = {
1461 	.fifo_lvl_mask	= { 0x1ff, 0x7F },
1462 	.rx_lvl_offset	= 15,
1463 	.tx_st_done	= 25,
1464 	.high_speed	= true,
1465 };
1466 
1467 static struct s3c64xx_spi_port_config exynos4_spi_port_config = {
1468 	.fifo_lvl_mask	= { 0x1ff, 0x7F, 0x7F },
1469 	.rx_lvl_offset	= 15,
1470 	.tx_st_done	= 25,
1471 	.high_speed	= true,
1472 	.clk_from_cmu	= true,
1473 };
1474 
1475 static struct platform_device_id s3c64xx_spi_driver_ids[] = {
1476 	{
1477 		.name		= "s3c2443-spi",
1478 		.driver_data	= (kernel_ulong_t)&s3c2443_spi_port_config,
1479 	}, {
1480 		.name		= "s3c6410-spi",
1481 		.driver_data	= (kernel_ulong_t)&s3c6410_spi_port_config,
1482 	}, {
1483 		.name		= "s5p64x0-spi",
1484 		.driver_data	= (kernel_ulong_t)&s5p64x0_spi_port_config,
1485 	}, {
1486 		.name		= "s5pc100-spi",
1487 		.driver_data	= (kernel_ulong_t)&s5pc100_spi_port_config,
1488 	}, {
1489 		.name		= "s5pv210-spi",
1490 		.driver_data	= (kernel_ulong_t)&s5pv210_spi_port_config,
1491 	}, {
1492 		.name		= "exynos4210-spi",
1493 		.driver_data	= (kernel_ulong_t)&exynos4_spi_port_config,
1494 	},
1495 	{ },
1496 };
1497 
1498 #ifdef CONFIG_OF
1499 static const struct of_device_id s3c64xx_spi_dt_match[] = {
1500 	{ .compatible = "samsung,exynos4210-spi",
1501 			.data = (void *)&exynos4_spi_port_config,
1502 	},
1503 	{ },
1504 };
1505 MODULE_DEVICE_TABLE(of, s3c64xx_spi_dt_match);
1506 #endif /* CONFIG_OF */
1507 
1508 static struct platform_driver s3c64xx_spi_driver = {
1509 	.driver = {
1510 		.name	= "s3c64xx-spi",
1511 		.owner = THIS_MODULE,
1512 		.pm = &s3c64xx_spi_pm,
1513 		.of_match_table = of_match_ptr(s3c64xx_spi_dt_match),
1514 	},
1515 	.remove = s3c64xx_spi_remove,
1516 	.id_table = s3c64xx_spi_driver_ids,
1517 };
1518 MODULE_ALIAS("platform:s3c64xx-spi");
1519 
1520 static int __init s3c64xx_spi_init(void)
1521 {
1522 	return platform_driver_probe(&s3c64xx_spi_driver, s3c64xx_spi_probe);
1523 }
1524 subsys_initcall(s3c64xx_spi_init);
1525 
1526 static void __exit s3c64xx_spi_exit(void)
1527 {
1528 	platform_driver_unregister(&s3c64xx_spi_driver);
1529 }
1530 module_exit(s3c64xx_spi_exit);
1531 
1532 MODULE_AUTHOR("Jaswinder Singh <jassi.brar@samsung.com>");
1533 MODULE_DESCRIPTION("S3C64XX SPI Controller Driver");
1534 MODULE_LICENSE("GPL");
1535