xref: /linux/drivers/spi/spi-s3c64xx.c (revision 80d443e8876602be2c130f79c4de81e12e2a700d)
1 /*
2  * Copyright (C) 2009 Samsung Electronics Ltd.
3  *	Jaswinder Singh <jassi.brar@samsung.com>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  */
15 
16 #include <linux/init.h>
17 #include <linux/module.h>
18 #include <linux/interrupt.h>
19 #include <linux/delay.h>
20 #include <linux/clk.h>
21 #include <linux/dma-mapping.h>
22 #include <linux/dmaengine.h>
23 #include <linux/platform_device.h>
24 #include <linux/pm_runtime.h>
25 #include <linux/spi/spi.h>
26 #include <linux/gpio.h>
27 #include <linux/of.h>
28 #include <linux/of_gpio.h>
29 
30 #include <linux/platform_data/spi-s3c64xx.h>
31 
32 #define MAX_SPI_PORTS		6
33 #define S3C64XX_SPI_QUIRK_POLL		(1 << 0)
34 #define S3C64XX_SPI_QUIRK_CS_AUTO	(1 << 1)
35 #define AUTOSUSPEND_TIMEOUT	2000
36 
37 /* Registers and bit-fields */
38 
39 #define S3C64XX_SPI_CH_CFG		0x00
40 #define S3C64XX_SPI_CLK_CFG		0x04
41 #define S3C64XX_SPI_MODE_CFG	0x08
42 #define S3C64XX_SPI_SLAVE_SEL	0x0C
43 #define S3C64XX_SPI_INT_EN		0x10
44 #define S3C64XX_SPI_STATUS		0x14
45 #define S3C64XX_SPI_TX_DATA		0x18
46 #define S3C64XX_SPI_RX_DATA		0x1C
47 #define S3C64XX_SPI_PACKET_CNT	0x20
48 #define S3C64XX_SPI_PENDING_CLR	0x24
49 #define S3C64XX_SPI_SWAP_CFG	0x28
50 #define S3C64XX_SPI_FB_CLK		0x2C
51 
52 #define S3C64XX_SPI_CH_HS_EN		(1<<6)	/* High Speed Enable */
53 #define S3C64XX_SPI_CH_SW_RST		(1<<5)
54 #define S3C64XX_SPI_CH_SLAVE		(1<<4)
55 #define S3C64XX_SPI_CPOL_L		(1<<3)
56 #define S3C64XX_SPI_CPHA_B		(1<<2)
57 #define S3C64XX_SPI_CH_RXCH_ON		(1<<1)
58 #define S3C64XX_SPI_CH_TXCH_ON		(1<<0)
59 
60 #define S3C64XX_SPI_CLKSEL_SRCMSK	(3<<9)
61 #define S3C64XX_SPI_CLKSEL_SRCSHFT	9
62 #define S3C64XX_SPI_ENCLK_ENABLE	(1<<8)
63 #define S3C64XX_SPI_PSR_MASK		0xff
64 
65 #define S3C64XX_SPI_MODE_CH_TSZ_BYTE		(0<<29)
66 #define S3C64XX_SPI_MODE_CH_TSZ_HALFWORD	(1<<29)
67 #define S3C64XX_SPI_MODE_CH_TSZ_WORD		(2<<29)
68 #define S3C64XX_SPI_MODE_CH_TSZ_MASK		(3<<29)
69 #define S3C64XX_SPI_MODE_BUS_TSZ_BYTE		(0<<17)
70 #define S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD	(1<<17)
71 #define S3C64XX_SPI_MODE_BUS_TSZ_WORD		(2<<17)
72 #define S3C64XX_SPI_MODE_BUS_TSZ_MASK		(3<<17)
73 #define S3C64XX_SPI_MODE_RXDMA_ON		(1<<2)
74 #define S3C64XX_SPI_MODE_TXDMA_ON		(1<<1)
75 #define S3C64XX_SPI_MODE_4BURST			(1<<0)
76 
77 #define S3C64XX_SPI_SLAVE_AUTO			(1<<1)
78 #define S3C64XX_SPI_SLAVE_SIG_INACT		(1<<0)
79 #define S3C64XX_SPI_SLAVE_NSC_CNT_2		(2<<4)
80 
81 #define S3C64XX_SPI_INT_TRAILING_EN		(1<<6)
82 #define S3C64XX_SPI_INT_RX_OVERRUN_EN		(1<<5)
83 #define S3C64XX_SPI_INT_RX_UNDERRUN_EN		(1<<4)
84 #define S3C64XX_SPI_INT_TX_OVERRUN_EN		(1<<3)
85 #define S3C64XX_SPI_INT_TX_UNDERRUN_EN		(1<<2)
86 #define S3C64XX_SPI_INT_RX_FIFORDY_EN		(1<<1)
87 #define S3C64XX_SPI_INT_TX_FIFORDY_EN		(1<<0)
88 
89 #define S3C64XX_SPI_ST_RX_OVERRUN_ERR		(1<<5)
90 #define S3C64XX_SPI_ST_RX_UNDERRUN_ERR	(1<<4)
91 #define S3C64XX_SPI_ST_TX_OVERRUN_ERR		(1<<3)
92 #define S3C64XX_SPI_ST_TX_UNDERRUN_ERR	(1<<2)
93 #define S3C64XX_SPI_ST_RX_FIFORDY		(1<<1)
94 #define S3C64XX_SPI_ST_TX_FIFORDY		(1<<0)
95 
96 #define S3C64XX_SPI_PACKET_CNT_EN		(1<<16)
97 
98 #define S3C64XX_SPI_PND_TX_UNDERRUN_CLR		(1<<4)
99 #define S3C64XX_SPI_PND_TX_OVERRUN_CLR		(1<<3)
100 #define S3C64XX_SPI_PND_RX_UNDERRUN_CLR		(1<<2)
101 #define S3C64XX_SPI_PND_RX_OVERRUN_CLR		(1<<1)
102 #define S3C64XX_SPI_PND_TRAILING_CLR		(1<<0)
103 
104 #define S3C64XX_SPI_SWAP_RX_HALF_WORD		(1<<7)
105 #define S3C64XX_SPI_SWAP_RX_BYTE		(1<<6)
106 #define S3C64XX_SPI_SWAP_RX_BIT			(1<<5)
107 #define S3C64XX_SPI_SWAP_RX_EN			(1<<4)
108 #define S3C64XX_SPI_SWAP_TX_HALF_WORD		(1<<3)
109 #define S3C64XX_SPI_SWAP_TX_BYTE		(1<<2)
110 #define S3C64XX_SPI_SWAP_TX_BIT			(1<<1)
111 #define S3C64XX_SPI_SWAP_TX_EN			(1<<0)
112 
113 #define S3C64XX_SPI_FBCLK_MSK		(3<<0)
114 
115 #define FIFO_LVL_MASK(i) ((i)->port_conf->fifo_lvl_mask[i->port_id])
116 #define S3C64XX_SPI_ST_TX_DONE(v, i) (((v) & \
117 				(1 << (i)->port_conf->tx_st_done)) ? 1 : 0)
118 #define TX_FIFO_LVL(v, i) (((v) >> 6) & FIFO_LVL_MASK(i))
119 #define RX_FIFO_LVL(v, i) (((v) >> (i)->port_conf->rx_lvl_offset) & \
120 					FIFO_LVL_MASK(i))
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 #define is_polling(x)	(x->port_conf->quirks & S3C64XX_SPI_QUIRK_POLL)
129 
130 #define RXBUSY    (1<<2)
131 #define TXBUSY    (1<<3)
132 
133 struct s3c64xx_spi_dma_data {
134 	struct dma_chan *ch;
135 	enum dma_transfer_direction direction;
136 };
137 
138 /**
139  * struct s3c64xx_spi_info - SPI Controller hardware info
140  * @fifo_lvl_mask: Bit-mask for {TX|RX}_FIFO_LVL bits in SPI_STATUS register.
141  * @rx_lvl_offset: Bit offset of RX_FIFO_LVL bits in SPI_STATUS regiter.
142  * @tx_st_done: Bit offset of TX_DONE bit in SPI_STATUS regiter.
143  * @high_speed: True, if the controller supports HIGH_SPEED_EN bit.
144  * @clk_from_cmu: True, if the controller does not include a clock mux and
145  *	prescaler unit.
146  *
147  * The Samsung s3c64xx SPI controller are used on various Samsung SoC's but
148  * differ in some aspects such as the size of the fifo and spi bus clock
149  * setup. Such differences are specified to the driver using this structure
150  * which is provided as driver data to the driver.
151  */
152 struct s3c64xx_spi_port_config {
153 	int	fifo_lvl_mask[MAX_SPI_PORTS];
154 	int	rx_lvl_offset;
155 	int	tx_st_done;
156 	int	quirks;
157 	bool	high_speed;
158 	bool	clk_from_cmu;
159 	bool	clk_ioclk;
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  * @ioclk: Pointer to the i/o clock between master and slave
167  * @master: Pointer to the SPI Protocol master.
168  * @cntrlr_info: Platform specific data for the controller this driver manages.
169  * @tgl_spi: Pointer to the last CS left untoggled by the cs_change hint.
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 clk                      *ioclk;
187 	struct platform_device          *pdev;
188 	struct spi_master               *master;
189 	struct s3c64xx_spi_info  *cntrlr_info;
190 	struct spi_device               *tgl_spi;
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 s3c64xx_spi_port_config	*port_conf;
200 	unsigned int			port_id;
201 };
202 
203 static void flush_fifo(struct s3c64xx_spi_driver_data *sdd)
204 {
205 	void __iomem *regs = sdd->regs;
206 	unsigned long loops;
207 	u32 val;
208 
209 	writel(0, regs + S3C64XX_SPI_PACKET_CNT);
210 
211 	val = readl(regs + S3C64XX_SPI_CH_CFG);
212 	val &= ~(S3C64XX_SPI_CH_RXCH_ON | S3C64XX_SPI_CH_TXCH_ON);
213 	writel(val, regs + S3C64XX_SPI_CH_CFG);
214 
215 	val = readl(regs + S3C64XX_SPI_CH_CFG);
216 	val |= S3C64XX_SPI_CH_SW_RST;
217 	val &= ~S3C64XX_SPI_CH_HS_EN;
218 	writel(val, regs + S3C64XX_SPI_CH_CFG);
219 
220 	/* Flush TxFIFO*/
221 	loops = msecs_to_loops(1);
222 	do {
223 		val = readl(regs + S3C64XX_SPI_STATUS);
224 	} while (TX_FIFO_LVL(val, sdd) && loops--);
225 
226 	if (loops == 0)
227 		dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n");
228 
229 	/* Flush RxFIFO*/
230 	loops = msecs_to_loops(1);
231 	do {
232 		val = readl(regs + S3C64XX_SPI_STATUS);
233 		if (RX_FIFO_LVL(val, sdd))
234 			readl(regs + S3C64XX_SPI_RX_DATA);
235 		else
236 			break;
237 	} while (loops--);
238 
239 	if (loops == 0)
240 		dev_warn(&sdd->pdev->dev, "Timed out flushing RX FIFO\n");
241 
242 	val = readl(regs + S3C64XX_SPI_CH_CFG);
243 	val &= ~S3C64XX_SPI_CH_SW_RST;
244 	writel(val, regs + S3C64XX_SPI_CH_CFG);
245 
246 	val = readl(regs + S3C64XX_SPI_MODE_CFG);
247 	val &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
248 	writel(val, regs + S3C64XX_SPI_MODE_CFG);
249 }
250 
251 static void s3c64xx_spi_dmacb(void *data)
252 {
253 	struct s3c64xx_spi_driver_data *sdd;
254 	struct s3c64xx_spi_dma_data *dma = data;
255 	unsigned long flags;
256 
257 	if (dma->direction == DMA_DEV_TO_MEM)
258 		sdd = container_of(data,
259 			struct s3c64xx_spi_driver_data, rx_dma);
260 	else
261 		sdd = container_of(data,
262 			struct s3c64xx_spi_driver_data, tx_dma);
263 
264 	spin_lock_irqsave(&sdd->lock, flags);
265 
266 	if (dma->direction == DMA_DEV_TO_MEM) {
267 		sdd->state &= ~RXBUSY;
268 		if (!(sdd->state & TXBUSY))
269 			complete(&sdd->xfer_completion);
270 	} else {
271 		sdd->state &= ~TXBUSY;
272 		if (!(sdd->state & RXBUSY))
273 			complete(&sdd->xfer_completion);
274 	}
275 
276 	spin_unlock_irqrestore(&sdd->lock, flags);
277 }
278 
279 static void prepare_dma(struct s3c64xx_spi_dma_data *dma,
280 			struct sg_table *sgt)
281 {
282 	struct s3c64xx_spi_driver_data *sdd;
283 	struct dma_slave_config config;
284 	struct dma_async_tx_descriptor *desc;
285 
286 	memset(&config, 0, sizeof(config));
287 
288 	if (dma->direction == DMA_DEV_TO_MEM) {
289 		sdd = container_of((void *)dma,
290 			struct s3c64xx_spi_driver_data, rx_dma);
291 		config.direction = dma->direction;
292 		config.src_addr = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
293 		config.src_addr_width = sdd->cur_bpw / 8;
294 		config.src_maxburst = 1;
295 		dmaengine_slave_config(dma->ch, &config);
296 	} else {
297 		sdd = container_of((void *)dma,
298 			struct s3c64xx_spi_driver_data, tx_dma);
299 		config.direction = dma->direction;
300 		config.dst_addr = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
301 		config.dst_addr_width = sdd->cur_bpw / 8;
302 		config.dst_maxburst = 1;
303 		dmaengine_slave_config(dma->ch, &config);
304 	}
305 
306 	desc = dmaengine_prep_slave_sg(dma->ch, sgt->sgl, sgt->nents,
307 				       dma->direction, DMA_PREP_INTERRUPT);
308 
309 	desc->callback = s3c64xx_spi_dmacb;
310 	desc->callback_param = dma;
311 
312 	dmaengine_submit(desc);
313 	dma_async_issue_pending(dma->ch);
314 }
315 
316 static void s3c64xx_spi_set_cs(struct spi_device *spi, bool enable)
317 {
318 	struct s3c64xx_spi_driver_data *sdd =
319 					spi_master_get_devdata(spi->master);
320 
321 	if (sdd->cntrlr_info->no_cs)
322 		return;
323 
324 	if (enable) {
325 		if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO)) {
326 			writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
327 		} else {
328 			u32 ssel = readl(sdd->regs + S3C64XX_SPI_SLAVE_SEL);
329 
330 			ssel |= (S3C64XX_SPI_SLAVE_AUTO |
331 						S3C64XX_SPI_SLAVE_NSC_CNT_2);
332 			writel(ssel, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
333 		}
334 	} else {
335 		if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
336 			writel(S3C64XX_SPI_SLAVE_SIG_INACT,
337 			       sdd->regs + S3C64XX_SPI_SLAVE_SEL);
338 	}
339 }
340 
341 static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
342 {
343 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
344 	struct device *dev = &sdd->pdev->dev;
345 
346 	if (is_polling(sdd))
347 		return 0;
348 
349 	/* Acquire DMA channels */
350 	sdd->rx_dma.ch = dma_request_slave_channel(dev, "rx");
351 	if (!sdd->rx_dma.ch) {
352 		dev_err(dev, "Failed to get RX DMA channel\n");
353 		return -EBUSY;
354 	}
355 	spi->dma_rx = sdd->rx_dma.ch;
356 
357 	sdd->tx_dma.ch = dma_request_slave_channel(dev, "tx");
358 	if (!sdd->tx_dma.ch) {
359 		dev_err(dev, "Failed to get TX DMA channel\n");
360 		dma_release_channel(sdd->rx_dma.ch);
361 		return -EBUSY;
362 	}
363 	spi->dma_tx = sdd->tx_dma.ch;
364 
365 	return 0;
366 }
367 
368 static int s3c64xx_spi_unprepare_transfer(struct spi_master *spi)
369 {
370 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
371 
372 	/* Free DMA channels */
373 	if (!is_polling(sdd)) {
374 		dma_release_channel(sdd->rx_dma.ch);
375 		dma_release_channel(sdd->tx_dma.ch);
376 	}
377 
378 	return 0;
379 }
380 
381 static bool s3c64xx_spi_can_dma(struct spi_master *master,
382 				struct spi_device *spi,
383 				struct spi_transfer *xfer)
384 {
385 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
386 
387 	return xfer->len > (FIFO_LVL_MASK(sdd) >> 1) + 1;
388 }
389 
390 static void enable_datapath(struct s3c64xx_spi_driver_data *sdd,
391 				struct spi_device *spi,
392 				struct spi_transfer *xfer, int dma_mode)
393 {
394 	void __iomem *regs = sdd->regs;
395 	u32 modecfg, chcfg;
396 
397 	modecfg = readl(regs + S3C64XX_SPI_MODE_CFG);
398 	modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
399 
400 	chcfg = readl(regs + S3C64XX_SPI_CH_CFG);
401 	chcfg &= ~S3C64XX_SPI_CH_TXCH_ON;
402 
403 	if (dma_mode) {
404 		chcfg &= ~S3C64XX_SPI_CH_RXCH_ON;
405 	} else {
406 		/* Always shift in data in FIFO, even if xfer is Tx only,
407 		 * this helps setting PCKT_CNT value for generating clocks
408 		 * as exactly needed.
409 		 */
410 		chcfg |= S3C64XX_SPI_CH_RXCH_ON;
411 		writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
412 					| S3C64XX_SPI_PACKET_CNT_EN,
413 					regs + S3C64XX_SPI_PACKET_CNT);
414 	}
415 
416 	if (xfer->tx_buf != NULL) {
417 		sdd->state |= TXBUSY;
418 		chcfg |= S3C64XX_SPI_CH_TXCH_ON;
419 		if (dma_mode) {
420 			modecfg |= S3C64XX_SPI_MODE_TXDMA_ON;
421 			prepare_dma(&sdd->tx_dma, &xfer->tx_sg);
422 		} else {
423 			switch (sdd->cur_bpw) {
424 			case 32:
425 				iowrite32_rep(regs + S3C64XX_SPI_TX_DATA,
426 					xfer->tx_buf, xfer->len / 4);
427 				break;
428 			case 16:
429 				iowrite16_rep(regs + S3C64XX_SPI_TX_DATA,
430 					xfer->tx_buf, xfer->len / 2);
431 				break;
432 			default:
433 				iowrite8_rep(regs + S3C64XX_SPI_TX_DATA,
434 					xfer->tx_buf, xfer->len);
435 				break;
436 			}
437 		}
438 	}
439 
440 	if (xfer->rx_buf != NULL) {
441 		sdd->state |= RXBUSY;
442 
443 		if (sdd->port_conf->high_speed && sdd->cur_speed >= 30000000UL
444 					&& !(sdd->cur_mode & SPI_CPHA))
445 			chcfg |= S3C64XX_SPI_CH_HS_EN;
446 
447 		if (dma_mode) {
448 			modecfg |= S3C64XX_SPI_MODE_RXDMA_ON;
449 			chcfg |= S3C64XX_SPI_CH_RXCH_ON;
450 			writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
451 					| S3C64XX_SPI_PACKET_CNT_EN,
452 					regs + S3C64XX_SPI_PACKET_CNT);
453 			prepare_dma(&sdd->rx_dma, &xfer->rx_sg);
454 		}
455 	}
456 
457 	writel(modecfg, regs + S3C64XX_SPI_MODE_CFG);
458 	writel(chcfg, regs + S3C64XX_SPI_CH_CFG);
459 }
460 
461 static u32 s3c64xx_spi_wait_for_timeout(struct s3c64xx_spi_driver_data *sdd,
462 					int timeout_ms)
463 {
464 	void __iomem *regs = sdd->regs;
465 	unsigned long val = 1;
466 	u32 status;
467 
468 	/* max fifo depth available */
469 	u32 max_fifo = (FIFO_LVL_MASK(sdd) >> 1) + 1;
470 
471 	if (timeout_ms)
472 		val = msecs_to_loops(timeout_ms);
473 
474 	do {
475 		status = readl(regs + S3C64XX_SPI_STATUS);
476 	} while (RX_FIFO_LVL(status, sdd) < max_fifo && --val);
477 
478 	/* return the actual received data length */
479 	return RX_FIFO_LVL(status, sdd);
480 }
481 
482 static int wait_for_dma(struct s3c64xx_spi_driver_data *sdd,
483 			struct spi_transfer *xfer)
484 {
485 	void __iomem *regs = sdd->regs;
486 	unsigned long val;
487 	u32 status;
488 	int ms;
489 
490 	/* millisecs to xfer 'len' bytes @ 'cur_speed' */
491 	ms = xfer->len * 8 * 1000 / sdd->cur_speed;
492 	ms += 10; /* some tolerance */
493 
494 	val = msecs_to_jiffies(ms) + 10;
495 	val = wait_for_completion_timeout(&sdd->xfer_completion, val);
496 
497 	/*
498 	 * If the previous xfer was completed within timeout, then
499 	 * proceed further else return -EIO.
500 	 * DmaTx returns after simply writing data in the FIFO,
501 	 * w/o waiting for real transmission on the bus to finish.
502 	 * DmaRx returns only after Dma read data from FIFO which
503 	 * needs bus transmission to finish, so we don't worry if
504 	 * Xfer involved Rx(with or without Tx).
505 	 */
506 	if (val && !xfer->rx_buf) {
507 		val = msecs_to_loops(10);
508 		status = readl(regs + S3C64XX_SPI_STATUS);
509 		while ((TX_FIFO_LVL(status, sdd)
510 			|| !S3C64XX_SPI_ST_TX_DONE(status, sdd))
511 		       && --val) {
512 			cpu_relax();
513 			status = readl(regs + S3C64XX_SPI_STATUS);
514 		}
515 
516 	}
517 
518 	/* If timed out while checking rx/tx status return error */
519 	if (!val)
520 		return -EIO;
521 
522 	return 0;
523 }
524 
525 static int wait_for_pio(struct s3c64xx_spi_driver_data *sdd,
526 			struct spi_transfer *xfer)
527 {
528 	void __iomem *regs = sdd->regs;
529 	unsigned long val;
530 	u32 status;
531 	int loops;
532 	u32 cpy_len;
533 	u8 *buf;
534 	int ms;
535 
536 	/* millisecs to xfer 'len' bytes @ 'cur_speed' */
537 	ms = xfer->len * 8 * 1000 / sdd->cur_speed;
538 	ms += 10; /* some tolerance */
539 
540 	val = msecs_to_loops(ms);
541 	do {
542 		status = readl(regs + S3C64XX_SPI_STATUS);
543 	} while (RX_FIFO_LVL(status, sdd) < xfer->len && --val);
544 
545 
546 	/* If it was only Tx */
547 	if (!xfer->rx_buf) {
548 		sdd->state &= ~TXBUSY;
549 		return 0;
550 	}
551 
552 	/*
553 	 * If the receive length is bigger than the controller fifo
554 	 * size, calculate the loops and read the fifo as many times.
555 	 * loops = length / max fifo size (calculated by using the
556 	 * fifo mask).
557 	 * For any size less than the fifo size the below code is
558 	 * executed atleast once.
559 	 */
560 	loops = xfer->len / ((FIFO_LVL_MASK(sdd) >> 1) + 1);
561 	buf = xfer->rx_buf;
562 	do {
563 		/* wait for data to be received in the fifo */
564 		cpy_len = s3c64xx_spi_wait_for_timeout(sdd,
565 						       (loops ? ms : 0));
566 
567 		switch (sdd->cur_bpw) {
568 		case 32:
569 			ioread32_rep(regs + S3C64XX_SPI_RX_DATA,
570 				     buf, cpy_len / 4);
571 			break;
572 		case 16:
573 			ioread16_rep(regs + S3C64XX_SPI_RX_DATA,
574 				     buf, cpy_len / 2);
575 			break;
576 		default:
577 			ioread8_rep(regs + S3C64XX_SPI_RX_DATA,
578 				    buf, cpy_len);
579 			break;
580 		}
581 
582 		buf = buf + cpy_len;
583 	} while (loops--);
584 	sdd->state &= ~RXBUSY;
585 
586 	return 0;
587 }
588 
589 static void s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
590 {
591 	void __iomem *regs = sdd->regs;
592 	u32 val;
593 
594 	/* Disable Clock */
595 	if (!sdd->port_conf->clk_from_cmu) {
596 		val = readl(regs + S3C64XX_SPI_CLK_CFG);
597 		val &= ~S3C64XX_SPI_ENCLK_ENABLE;
598 		writel(val, regs + S3C64XX_SPI_CLK_CFG);
599 	}
600 
601 	/* Set Polarity and Phase */
602 	val = readl(regs + S3C64XX_SPI_CH_CFG);
603 	val &= ~(S3C64XX_SPI_CH_SLAVE |
604 			S3C64XX_SPI_CPOL_L |
605 			S3C64XX_SPI_CPHA_B);
606 
607 	if (sdd->cur_mode & SPI_CPOL)
608 		val |= S3C64XX_SPI_CPOL_L;
609 
610 	if (sdd->cur_mode & SPI_CPHA)
611 		val |= S3C64XX_SPI_CPHA_B;
612 
613 	writel(val, regs + S3C64XX_SPI_CH_CFG);
614 
615 	/* Set Channel & DMA Mode */
616 	val = readl(regs + S3C64XX_SPI_MODE_CFG);
617 	val &= ~(S3C64XX_SPI_MODE_BUS_TSZ_MASK
618 			| S3C64XX_SPI_MODE_CH_TSZ_MASK);
619 
620 	switch (sdd->cur_bpw) {
621 	case 32:
622 		val |= S3C64XX_SPI_MODE_BUS_TSZ_WORD;
623 		val |= S3C64XX_SPI_MODE_CH_TSZ_WORD;
624 		break;
625 	case 16:
626 		val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD;
627 		val |= S3C64XX_SPI_MODE_CH_TSZ_HALFWORD;
628 		break;
629 	default:
630 		val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE;
631 		val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE;
632 		break;
633 	}
634 
635 	writel(val, regs + S3C64XX_SPI_MODE_CFG);
636 
637 	if (sdd->port_conf->clk_from_cmu) {
638 		/* The src_clk clock is divided internally by 2 */
639 		clk_set_rate(sdd->src_clk, sdd->cur_speed * 2);
640 	} else {
641 		/* Configure Clock */
642 		val = readl(regs + S3C64XX_SPI_CLK_CFG);
643 		val &= ~S3C64XX_SPI_PSR_MASK;
644 		val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / 2 - 1)
645 				& S3C64XX_SPI_PSR_MASK);
646 		writel(val, regs + S3C64XX_SPI_CLK_CFG);
647 
648 		/* Enable Clock */
649 		val = readl(regs + S3C64XX_SPI_CLK_CFG);
650 		val |= S3C64XX_SPI_ENCLK_ENABLE;
651 		writel(val, regs + S3C64XX_SPI_CLK_CFG);
652 	}
653 }
654 
655 #define XFER_DMAADDR_INVALID DMA_BIT_MASK(32)
656 
657 static int s3c64xx_spi_prepare_message(struct spi_master *master,
658 				       struct spi_message *msg)
659 {
660 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
661 	struct spi_device *spi = msg->spi;
662 	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
663 
664 	/* Configure feedback delay */
665 	writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK);
666 
667 	return 0;
668 }
669 
670 static int s3c64xx_spi_transfer_one(struct spi_master *master,
671 				    struct spi_device *spi,
672 				    struct spi_transfer *xfer)
673 {
674 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
675 	int status;
676 	u32 speed;
677 	u8 bpw;
678 	unsigned long flags;
679 	int use_dma;
680 
681 	reinit_completion(&sdd->xfer_completion);
682 
683 	/* Only BPW and Speed may change across transfers */
684 	bpw = xfer->bits_per_word;
685 	speed = xfer->speed_hz;
686 
687 	if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) {
688 		sdd->cur_bpw = bpw;
689 		sdd->cur_speed = speed;
690 		sdd->cur_mode = spi->mode;
691 		s3c64xx_spi_config(sdd);
692 	}
693 
694 	/* Polling method for xfers not bigger than FIFO capacity */
695 	use_dma = 0;
696 	if (!is_polling(sdd) &&
697 	    (sdd->rx_dma.ch && sdd->tx_dma.ch &&
698 	     (xfer->len > ((FIFO_LVL_MASK(sdd) >> 1) + 1))))
699 		use_dma = 1;
700 
701 	spin_lock_irqsave(&sdd->lock, flags);
702 
703 	/* Pending only which is to be done */
704 	sdd->state &= ~RXBUSY;
705 	sdd->state &= ~TXBUSY;
706 
707 	enable_datapath(sdd, spi, xfer, use_dma);
708 
709 	/* Start the signals */
710 	s3c64xx_spi_set_cs(spi, true);
711 
712 	spin_unlock_irqrestore(&sdd->lock, flags);
713 
714 	if (use_dma)
715 		status = wait_for_dma(sdd, xfer);
716 	else
717 		status = wait_for_pio(sdd, xfer);
718 
719 	if (status) {
720 		dev_err(&spi->dev, "I/O Error: rx-%d tx-%d res:rx-%c tx-%c len-%d\n",
721 			xfer->rx_buf ? 1 : 0, xfer->tx_buf ? 1 : 0,
722 			(sdd->state & RXBUSY) ? 'f' : 'p',
723 			(sdd->state & TXBUSY) ? 'f' : 'p',
724 			xfer->len);
725 
726 		if (use_dma) {
727 			if (xfer->tx_buf != NULL
728 			    && (sdd->state & TXBUSY))
729 				dmaengine_terminate_all(sdd->tx_dma.ch);
730 			if (xfer->rx_buf != NULL
731 			    && (sdd->state & RXBUSY))
732 				dmaengine_terminate_all(sdd->rx_dma.ch);
733 		}
734 	} else {
735 		flush_fifo(sdd);
736 	}
737 
738 	return status;
739 }
740 
741 static struct s3c64xx_spi_csinfo *s3c64xx_get_slave_ctrldata(
742 				struct spi_device *spi)
743 {
744 	struct s3c64xx_spi_csinfo *cs;
745 	struct device_node *slave_np, *data_np = NULL;
746 	u32 fb_delay = 0;
747 
748 	slave_np = spi->dev.of_node;
749 	if (!slave_np) {
750 		dev_err(&spi->dev, "device node not found\n");
751 		return ERR_PTR(-EINVAL);
752 	}
753 
754 	data_np = of_get_child_by_name(slave_np, "controller-data");
755 	if (!data_np) {
756 		dev_err(&spi->dev, "child node 'controller-data' not found\n");
757 		return ERR_PTR(-EINVAL);
758 	}
759 
760 	cs = kzalloc(sizeof(*cs), GFP_KERNEL);
761 	if (!cs) {
762 		of_node_put(data_np);
763 		return ERR_PTR(-ENOMEM);
764 	}
765 
766 	of_property_read_u32(data_np, "samsung,spi-feedback-delay", &fb_delay);
767 	cs->fb_delay = fb_delay;
768 	of_node_put(data_np);
769 	return cs;
770 }
771 
772 /*
773  * Here we only check the validity of requested configuration
774  * and save the configuration in a local data-structure.
775  * The controller is actually configured only just before we
776  * get a message to transfer.
777  */
778 static int s3c64xx_spi_setup(struct spi_device *spi)
779 {
780 	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
781 	struct s3c64xx_spi_driver_data *sdd;
782 	struct s3c64xx_spi_info *sci;
783 	int err;
784 
785 	sdd = spi_master_get_devdata(spi->master);
786 	if (spi->dev.of_node) {
787 		cs = s3c64xx_get_slave_ctrldata(spi);
788 		spi->controller_data = cs;
789 	} else if (cs) {
790 		/* On non-DT platforms the SPI core will set spi->cs_gpio
791 		 * to -ENOENT. The GPIO pin used to drive the chip select
792 		 * is defined by using platform data so spi->cs_gpio value
793 		 * has to be override to have the proper GPIO pin number.
794 		 */
795 		spi->cs_gpio = cs->line;
796 	}
797 
798 	if (IS_ERR_OR_NULL(cs)) {
799 		dev_err(&spi->dev, "No CS for SPI(%d)\n", spi->chip_select);
800 		return -ENODEV;
801 	}
802 
803 	if (!spi_get_ctldata(spi)) {
804 		if (gpio_is_valid(spi->cs_gpio)) {
805 			err = gpio_request_one(spi->cs_gpio, GPIOF_OUT_INIT_HIGH,
806 					       dev_name(&spi->dev));
807 			if (err) {
808 				dev_err(&spi->dev,
809 					"Failed to get /CS gpio [%d]: %d\n",
810 					spi->cs_gpio, err);
811 				goto err_gpio_req;
812 			}
813 		}
814 
815 		spi_set_ctldata(spi, cs);
816 	}
817 
818 	sci = sdd->cntrlr_info;
819 
820 	pm_runtime_get_sync(&sdd->pdev->dev);
821 
822 	/* Check if we can provide the requested rate */
823 	if (!sdd->port_conf->clk_from_cmu) {
824 		u32 psr, speed;
825 
826 		/* Max possible */
827 		speed = clk_get_rate(sdd->src_clk) / 2 / (0 + 1);
828 
829 		if (spi->max_speed_hz > speed)
830 			spi->max_speed_hz = speed;
831 
832 		psr = clk_get_rate(sdd->src_clk) / 2 / spi->max_speed_hz - 1;
833 		psr &= S3C64XX_SPI_PSR_MASK;
834 		if (psr == S3C64XX_SPI_PSR_MASK)
835 			psr--;
836 
837 		speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
838 		if (spi->max_speed_hz < speed) {
839 			if (psr+1 < S3C64XX_SPI_PSR_MASK) {
840 				psr++;
841 			} else {
842 				err = -EINVAL;
843 				goto setup_exit;
844 			}
845 		}
846 
847 		speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
848 		if (spi->max_speed_hz >= speed) {
849 			spi->max_speed_hz = speed;
850 		} else {
851 			dev_err(&spi->dev, "Can't set %dHz transfer speed\n",
852 				spi->max_speed_hz);
853 			err = -EINVAL;
854 			goto setup_exit;
855 		}
856 	}
857 
858 	pm_runtime_mark_last_busy(&sdd->pdev->dev);
859 	pm_runtime_put_autosuspend(&sdd->pdev->dev);
860 	s3c64xx_spi_set_cs(spi, false);
861 
862 	return 0;
863 
864 setup_exit:
865 	pm_runtime_mark_last_busy(&sdd->pdev->dev);
866 	pm_runtime_put_autosuspend(&sdd->pdev->dev);
867 	/* setup() returns with device de-selected */
868 	s3c64xx_spi_set_cs(spi, false);
869 
870 	if (gpio_is_valid(spi->cs_gpio))
871 		gpio_free(spi->cs_gpio);
872 	spi_set_ctldata(spi, NULL);
873 
874 err_gpio_req:
875 	if (spi->dev.of_node)
876 		kfree(cs);
877 
878 	return err;
879 }
880 
881 static void s3c64xx_spi_cleanup(struct spi_device *spi)
882 {
883 	struct s3c64xx_spi_csinfo *cs = spi_get_ctldata(spi);
884 
885 	if (gpio_is_valid(spi->cs_gpio)) {
886 		gpio_free(spi->cs_gpio);
887 		if (spi->dev.of_node)
888 			kfree(cs);
889 		else {
890 			/* On non-DT platforms, the SPI core sets
891 			 * spi->cs_gpio to -ENOENT and .setup()
892 			 * overrides it with the GPIO pin value
893 			 * passed using platform data.
894 			 */
895 			spi->cs_gpio = -ENOENT;
896 		}
897 	}
898 
899 	spi_set_ctldata(spi, NULL);
900 }
901 
902 static irqreturn_t s3c64xx_spi_irq(int irq, void *data)
903 {
904 	struct s3c64xx_spi_driver_data *sdd = data;
905 	struct spi_master *spi = sdd->master;
906 	unsigned int val, clr = 0;
907 
908 	val = readl(sdd->regs + S3C64XX_SPI_STATUS);
909 
910 	if (val & S3C64XX_SPI_ST_RX_OVERRUN_ERR) {
911 		clr = S3C64XX_SPI_PND_RX_OVERRUN_CLR;
912 		dev_err(&spi->dev, "RX overrun\n");
913 	}
914 	if (val & S3C64XX_SPI_ST_RX_UNDERRUN_ERR) {
915 		clr |= S3C64XX_SPI_PND_RX_UNDERRUN_CLR;
916 		dev_err(&spi->dev, "RX underrun\n");
917 	}
918 	if (val & S3C64XX_SPI_ST_TX_OVERRUN_ERR) {
919 		clr |= S3C64XX_SPI_PND_TX_OVERRUN_CLR;
920 		dev_err(&spi->dev, "TX overrun\n");
921 	}
922 	if (val & S3C64XX_SPI_ST_TX_UNDERRUN_ERR) {
923 		clr |= S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
924 		dev_err(&spi->dev, "TX underrun\n");
925 	}
926 
927 	/* Clear the pending irq by setting and then clearing it */
928 	writel(clr, sdd->regs + S3C64XX_SPI_PENDING_CLR);
929 	writel(0, sdd->regs + S3C64XX_SPI_PENDING_CLR);
930 
931 	return IRQ_HANDLED;
932 }
933 
934 static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd, int channel)
935 {
936 	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
937 	void __iomem *regs = sdd->regs;
938 	unsigned int val;
939 
940 	sdd->cur_speed = 0;
941 
942 	if (sci->no_cs)
943 		writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
944 	else if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
945 		writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
946 
947 	/* Disable Interrupts - we use Polling if not DMA mode */
948 	writel(0, regs + S3C64XX_SPI_INT_EN);
949 
950 	if (!sdd->port_conf->clk_from_cmu)
951 		writel(sci->src_clk_nr << S3C64XX_SPI_CLKSEL_SRCSHFT,
952 				regs + S3C64XX_SPI_CLK_CFG);
953 	writel(0, regs + S3C64XX_SPI_MODE_CFG);
954 	writel(0, regs + S3C64XX_SPI_PACKET_CNT);
955 
956 	/* Clear any irq pending bits, should set and clear the bits */
957 	val = S3C64XX_SPI_PND_RX_OVERRUN_CLR |
958 		S3C64XX_SPI_PND_RX_UNDERRUN_CLR |
959 		S3C64XX_SPI_PND_TX_OVERRUN_CLR |
960 		S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
961 	writel(val, regs + S3C64XX_SPI_PENDING_CLR);
962 	writel(0, regs + S3C64XX_SPI_PENDING_CLR);
963 
964 	writel(0, regs + S3C64XX_SPI_SWAP_CFG);
965 
966 	val = readl(regs + S3C64XX_SPI_MODE_CFG);
967 	val &= ~S3C64XX_SPI_MODE_4BURST;
968 	val &= ~(S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
969 	val |= (S3C64XX_SPI_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
970 	writel(val, regs + S3C64XX_SPI_MODE_CFG);
971 
972 	flush_fifo(sdd);
973 }
974 
975 #ifdef CONFIG_OF
976 static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
977 {
978 	struct s3c64xx_spi_info *sci;
979 	u32 temp;
980 
981 	sci = devm_kzalloc(dev, sizeof(*sci), GFP_KERNEL);
982 	if (!sci)
983 		return ERR_PTR(-ENOMEM);
984 
985 	if (of_property_read_u32(dev->of_node, "samsung,spi-src-clk", &temp)) {
986 		dev_warn(dev, "spi bus clock parent not specified, using clock at index 0 as parent\n");
987 		sci->src_clk_nr = 0;
988 	} else {
989 		sci->src_clk_nr = temp;
990 	}
991 
992 	if (of_property_read_u32(dev->of_node, "num-cs", &temp)) {
993 		dev_warn(dev, "number of chip select lines not specified, assuming 1 chip select line\n");
994 		sci->num_cs = 1;
995 	} else {
996 		sci->num_cs = temp;
997 	}
998 
999 	sci->no_cs = of_property_read_bool(dev->of_node, "broken-cs");
1000 
1001 	return sci;
1002 }
1003 #else
1004 static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
1005 {
1006 	return dev_get_platdata(dev);
1007 }
1008 #endif
1009 
1010 static const struct of_device_id s3c64xx_spi_dt_match[];
1011 
1012 static inline struct s3c64xx_spi_port_config *s3c64xx_spi_get_port_config(
1013 						struct platform_device *pdev)
1014 {
1015 #ifdef CONFIG_OF
1016 	if (pdev->dev.of_node) {
1017 		const struct of_device_id *match;
1018 		match = of_match_node(s3c64xx_spi_dt_match, pdev->dev.of_node);
1019 		return (struct s3c64xx_spi_port_config *)match->data;
1020 	}
1021 #endif
1022 	return (struct s3c64xx_spi_port_config *)
1023 			 platform_get_device_id(pdev)->driver_data;
1024 }
1025 
1026 static int s3c64xx_spi_probe(struct platform_device *pdev)
1027 {
1028 	struct resource	*mem_res;
1029 	struct s3c64xx_spi_driver_data *sdd;
1030 	struct s3c64xx_spi_info *sci = dev_get_platdata(&pdev->dev);
1031 	struct spi_master *master;
1032 	int ret, irq;
1033 	char clk_name[16];
1034 
1035 	if (!sci && pdev->dev.of_node) {
1036 		sci = s3c64xx_spi_parse_dt(&pdev->dev);
1037 		if (IS_ERR(sci))
1038 			return PTR_ERR(sci);
1039 	}
1040 
1041 	if (!sci) {
1042 		dev_err(&pdev->dev, "platform_data missing!\n");
1043 		return -ENODEV;
1044 	}
1045 
1046 	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1047 	if (mem_res == NULL) {
1048 		dev_err(&pdev->dev, "Unable to get SPI MEM resource\n");
1049 		return -ENXIO;
1050 	}
1051 
1052 	irq = platform_get_irq(pdev, 0);
1053 	if (irq < 0) {
1054 		dev_warn(&pdev->dev, "Failed to get IRQ: %d\n", irq);
1055 		return irq;
1056 	}
1057 
1058 	master = spi_alloc_master(&pdev->dev,
1059 				sizeof(struct s3c64xx_spi_driver_data));
1060 	if (master == NULL) {
1061 		dev_err(&pdev->dev, "Unable to allocate SPI Master\n");
1062 		return -ENOMEM;
1063 	}
1064 
1065 	platform_set_drvdata(pdev, master);
1066 
1067 	sdd = spi_master_get_devdata(master);
1068 	sdd->port_conf = s3c64xx_spi_get_port_config(pdev);
1069 	sdd->master = master;
1070 	sdd->cntrlr_info = sci;
1071 	sdd->pdev = pdev;
1072 	sdd->sfr_start = mem_res->start;
1073 	if (pdev->dev.of_node) {
1074 		ret = of_alias_get_id(pdev->dev.of_node, "spi");
1075 		if (ret < 0) {
1076 			dev_err(&pdev->dev, "failed to get alias id, errno %d\n",
1077 				ret);
1078 			goto err_deref_master;
1079 		}
1080 		sdd->port_id = ret;
1081 	} else {
1082 		sdd->port_id = pdev->id;
1083 	}
1084 
1085 	sdd->cur_bpw = 8;
1086 
1087 	sdd->tx_dma.direction = DMA_MEM_TO_DEV;
1088 	sdd->rx_dma.direction = DMA_DEV_TO_MEM;
1089 
1090 	master->dev.of_node = pdev->dev.of_node;
1091 	master->bus_num = sdd->port_id;
1092 	master->setup = s3c64xx_spi_setup;
1093 	master->cleanup = s3c64xx_spi_cleanup;
1094 	master->prepare_transfer_hardware = s3c64xx_spi_prepare_transfer;
1095 	master->prepare_message = s3c64xx_spi_prepare_message;
1096 	master->transfer_one = s3c64xx_spi_transfer_one;
1097 	master->unprepare_transfer_hardware = s3c64xx_spi_unprepare_transfer;
1098 	master->num_chipselect = sci->num_cs;
1099 	master->dma_alignment = 8;
1100 	master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) |
1101 					SPI_BPW_MASK(8);
1102 	/* the spi->mode bits understood by this driver: */
1103 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1104 	master->auto_runtime_pm = true;
1105 	if (!is_polling(sdd))
1106 		master->can_dma = s3c64xx_spi_can_dma;
1107 
1108 	sdd->regs = devm_ioremap_resource(&pdev->dev, mem_res);
1109 	if (IS_ERR(sdd->regs)) {
1110 		ret = PTR_ERR(sdd->regs);
1111 		goto err_deref_master;
1112 	}
1113 
1114 	if (sci->cfg_gpio && sci->cfg_gpio()) {
1115 		dev_err(&pdev->dev, "Unable to config gpio\n");
1116 		ret = -EBUSY;
1117 		goto err_deref_master;
1118 	}
1119 
1120 	/* Setup clocks */
1121 	sdd->clk = devm_clk_get(&pdev->dev, "spi");
1122 	if (IS_ERR(sdd->clk)) {
1123 		dev_err(&pdev->dev, "Unable to acquire clock 'spi'\n");
1124 		ret = PTR_ERR(sdd->clk);
1125 		goto err_deref_master;
1126 	}
1127 
1128 	ret = clk_prepare_enable(sdd->clk);
1129 	if (ret) {
1130 		dev_err(&pdev->dev, "Couldn't enable clock 'spi'\n");
1131 		goto err_deref_master;
1132 	}
1133 
1134 	sprintf(clk_name, "spi_busclk%d", sci->src_clk_nr);
1135 	sdd->src_clk = devm_clk_get(&pdev->dev, clk_name);
1136 	if (IS_ERR(sdd->src_clk)) {
1137 		dev_err(&pdev->dev,
1138 			"Unable to acquire clock '%s'\n", clk_name);
1139 		ret = PTR_ERR(sdd->src_clk);
1140 		goto err_disable_clk;
1141 	}
1142 
1143 	ret = clk_prepare_enable(sdd->src_clk);
1144 	if (ret) {
1145 		dev_err(&pdev->dev, "Couldn't enable clock '%s'\n", clk_name);
1146 		goto err_disable_clk;
1147 	}
1148 
1149 	if (sdd->port_conf->clk_ioclk) {
1150 		sdd->ioclk = devm_clk_get(&pdev->dev, "spi_ioclk");
1151 		if (IS_ERR(sdd->ioclk)) {
1152 			dev_err(&pdev->dev, "Unable to acquire 'ioclk'\n");
1153 			ret = PTR_ERR(sdd->ioclk);
1154 			goto err_disable_src_clk;
1155 		}
1156 
1157 		ret = clk_prepare_enable(sdd->ioclk);
1158 		if (ret) {
1159 			dev_err(&pdev->dev, "Couldn't enable clock 'ioclk'\n");
1160 			goto err_disable_src_clk;
1161 		}
1162 	}
1163 
1164 	pm_runtime_set_autosuspend_delay(&pdev->dev, AUTOSUSPEND_TIMEOUT);
1165 	pm_runtime_use_autosuspend(&pdev->dev);
1166 	pm_runtime_set_active(&pdev->dev);
1167 	pm_runtime_enable(&pdev->dev);
1168 	pm_runtime_get_sync(&pdev->dev);
1169 
1170 	/* Setup Deufult Mode */
1171 	s3c64xx_spi_hwinit(sdd, sdd->port_id);
1172 
1173 	spin_lock_init(&sdd->lock);
1174 	init_completion(&sdd->xfer_completion);
1175 
1176 	ret = devm_request_irq(&pdev->dev, irq, s3c64xx_spi_irq, 0,
1177 				"spi-s3c64xx", sdd);
1178 	if (ret != 0) {
1179 		dev_err(&pdev->dev, "Failed to request IRQ %d: %d\n",
1180 			irq, ret);
1181 		goto err_pm_put;
1182 	}
1183 
1184 	writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
1185 	       S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
1186 	       sdd->regs + S3C64XX_SPI_INT_EN);
1187 
1188 	ret = devm_spi_register_master(&pdev->dev, master);
1189 	if (ret != 0) {
1190 		dev_err(&pdev->dev, "cannot register SPI master: %d\n", ret);
1191 		goto err_pm_put;
1192 	}
1193 
1194 	dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d with %d Slaves attached\n",
1195 					sdd->port_id, master->num_chipselect);
1196 	dev_dbg(&pdev->dev, "\tIOmem=[%pR]\tFIFO %dbytes\n",
1197 					mem_res, (FIFO_LVL_MASK(sdd) >> 1) + 1);
1198 
1199 	pm_runtime_mark_last_busy(&pdev->dev);
1200 	pm_runtime_put_autosuspend(&pdev->dev);
1201 
1202 	return 0;
1203 
1204 err_pm_put:
1205 	pm_runtime_put_noidle(&pdev->dev);
1206 	pm_runtime_disable(&pdev->dev);
1207 	pm_runtime_set_suspended(&pdev->dev);
1208 
1209 	clk_disable_unprepare(sdd->ioclk);
1210 err_disable_src_clk:
1211 	clk_disable_unprepare(sdd->src_clk);
1212 err_disable_clk:
1213 	clk_disable_unprepare(sdd->clk);
1214 err_deref_master:
1215 	spi_master_put(master);
1216 
1217 	return ret;
1218 }
1219 
1220 static int s3c64xx_spi_remove(struct platform_device *pdev)
1221 {
1222 	struct spi_master *master = platform_get_drvdata(pdev);
1223 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1224 
1225 	pm_runtime_get_sync(&pdev->dev);
1226 
1227 	writel(0, sdd->regs + S3C64XX_SPI_INT_EN);
1228 
1229 	clk_disable_unprepare(sdd->ioclk);
1230 
1231 	clk_disable_unprepare(sdd->src_clk);
1232 
1233 	clk_disable_unprepare(sdd->clk);
1234 
1235 	pm_runtime_put_noidle(&pdev->dev);
1236 	pm_runtime_disable(&pdev->dev);
1237 	pm_runtime_set_suspended(&pdev->dev);
1238 
1239 	return 0;
1240 }
1241 
1242 #ifdef CONFIG_PM_SLEEP
1243 static int s3c64xx_spi_suspend(struct device *dev)
1244 {
1245 	struct spi_master *master = dev_get_drvdata(dev);
1246 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1247 
1248 	int ret = spi_master_suspend(master);
1249 	if (ret)
1250 		return ret;
1251 
1252 	ret = pm_runtime_force_suspend(dev);
1253 	if (ret < 0)
1254 		return ret;
1255 
1256 	sdd->cur_speed = 0; /* Output Clock is stopped */
1257 
1258 	return 0;
1259 }
1260 
1261 static int s3c64xx_spi_resume(struct device *dev)
1262 {
1263 	struct spi_master *master = dev_get_drvdata(dev);
1264 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1265 	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1266 	int ret;
1267 
1268 	if (sci->cfg_gpio)
1269 		sci->cfg_gpio();
1270 
1271 	ret = pm_runtime_force_resume(dev);
1272 	if (ret < 0)
1273 		return ret;
1274 
1275 	s3c64xx_spi_hwinit(sdd, sdd->port_id);
1276 
1277 	return spi_master_resume(master);
1278 }
1279 #endif /* CONFIG_PM_SLEEP */
1280 
1281 #ifdef CONFIG_PM
1282 static int s3c64xx_spi_runtime_suspend(struct device *dev)
1283 {
1284 	struct spi_master *master = dev_get_drvdata(dev);
1285 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1286 
1287 	clk_disable_unprepare(sdd->clk);
1288 	clk_disable_unprepare(sdd->src_clk);
1289 	clk_disable_unprepare(sdd->ioclk);
1290 
1291 	return 0;
1292 }
1293 
1294 static int s3c64xx_spi_runtime_resume(struct device *dev)
1295 {
1296 	struct spi_master *master = dev_get_drvdata(dev);
1297 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1298 	int ret;
1299 
1300 	if (sdd->port_conf->clk_ioclk) {
1301 		ret = clk_prepare_enable(sdd->ioclk);
1302 		if (ret != 0)
1303 			return ret;
1304 	}
1305 
1306 	ret = clk_prepare_enable(sdd->src_clk);
1307 	if (ret != 0)
1308 		goto err_disable_ioclk;
1309 
1310 	ret = clk_prepare_enable(sdd->clk);
1311 	if (ret != 0)
1312 		goto err_disable_src_clk;
1313 
1314 	return 0;
1315 
1316 err_disable_src_clk:
1317 	clk_disable_unprepare(sdd->src_clk);
1318 err_disable_ioclk:
1319 	clk_disable_unprepare(sdd->ioclk);
1320 
1321 	return ret;
1322 }
1323 #endif /* CONFIG_PM */
1324 
1325 static const struct dev_pm_ops s3c64xx_spi_pm = {
1326 	SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume)
1327 	SET_RUNTIME_PM_OPS(s3c64xx_spi_runtime_suspend,
1328 			   s3c64xx_spi_runtime_resume, NULL)
1329 };
1330 
1331 static struct s3c64xx_spi_port_config s3c2443_spi_port_config = {
1332 	.fifo_lvl_mask	= { 0x7f },
1333 	.rx_lvl_offset	= 13,
1334 	.tx_st_done	= 21,
1335 	.high_speed	= true,
1336 };
1337 
1338 static struct s3c64xx_spi_port_config s3c6410_spi_port_config = {
1339 	.fifo_lvl_mask	= { 0x7f, 0x7F },
1340 	.rx_lvl_offset	= 13,
1341 	.tx_st_done	= 21,
1342 };
1343 
1344 static struct s3c64xx_spi_port_config s5pv210_spi_port_config = {
1345 	.fifo_lvl_mask	= { 0x1ff, 0x7F },
1346 	.rx_lvl_offset	= 15,
1347 	.tx_st_done	= 25,
1348 	.high_speed	= true,
1349 };
1350 
1351 static struct s3c64xx_spi_port_config exynos4_spi_port_config = {
1352 	.fifo_lvl_mask	= { 0x1ff, 0x7F, 0x7F },
1353 	.rx_lvl_offset	= 15,
1354 	.tx_st_done	= 25,
1355 	.high_speed	= true,
1356 	.clk_from_cmu	= true,
1357 };
1358 
1359 static struct s3c64xx_spi_port_config exynos5440_spi_port_config = {
1360 	.fifo_lvl_mask	= { 0x1ff },
1361 	.rx_lvl_offset	= 15,
1362 	.tx_st_done	= 25,
1363 	.high_speed	= true,
1364 	.clk_from_cmu	= true,
1365 	.quirks		= S3C64XX_SPI_QUIRK_POLL,
1366 };
1367 
1368 static struct s3c64xx_spi_port_config exynos7_spi_port_config = {
1369 	.fifo_lvl_mask	= { 0x1ff, 0x7F, 0x7F, 0x7F, 0x7F, 0x1ff},
1370 	.rx_lvl_offset	= 15,
1371 	.tx_st_done	= 25,
1372 	.high_speed	= true,
1373 	.clk_from_cmu	= true,
1374 	.quirks		= S3C64XX_SPI_QUIRK_CS_AUTO,
1375 };
1376 
1377 static struct s3c64xx_spi_port_config exynos5433_spi_port_config = {
1378 	.fifo_lvl_mask	= { 0x1ff, 0x7f, 0x7f, 0x7f, 0x7f, 0x1ff},
1379 	.rx_lvl_offset	= 15,
1380 	.tx_st_done	= 25,
1381 	.high_speed	= true,
1382 	.clk_from_cmu	= true,
1383 	.clk_ioclk	= true,
1384 	.quirks		= S3C64XX_SPI_QUIRK_CS_AUTO,
1385 };
1386 
1387 static const struct platform_device_id s3c64xx_spi_driver_ids[] = {
1388 	{
1389 		.name		= "s3c2443-spi",
1390 		.driver_data	= (kernel_ulong_t)&s3c2443_spi_port_config,
1391 	}, {
1392 		.name		= "s3c6410-spi",
1393 		.driver_data	= (kernel_ulong_t)&s3c6410_spi_port_config,
1394 	},
1395 	{ },
1396 };
1397 
1398 static const struct of_device_id s3c64xx_spi_dt_match[] = {
1399 	{ .compatible = "samsung,s3c2443-spi",
1400 			.data = (void *)&s3c2443_spi_port_config,
1401 	},
1402 	{ .compatible = "samsung,s3c6410-spi",
1403 			.data = (void *)&s3c6410_spi_port_config,
1404 	},
1405 	{ .compatible = "samsung,s5pv210-spi",
1406 			.data = (void *)&s5pv210_spi_port_config,
1407 	},
1408 	{ .compatible = "samsung,exynos4210-spi",
1409 			.data = (void *)&exynos4_spi_port_config,
1410 	},
1411 	{ .compatible = "samsung,exynos5440-spi",
1412 			.data = (void *)&exynos5440_spi_port_config,
1413 	},
1414 	{ .compatible = "samsung,exynos7-spi",
1415 			.data = (void *)&exynos7_spi_port_config,
1416 	},
1417 	{ .compatible = "samsung,exynos5433-spi",
1418 			.data = (void *)&exynos5433_spi_port_config,
1419 	},
1420 	{ },
1421 };
1422 MODULE_DEVICE_TABLE(of, s3c64xx_spi_dt_match);
1423 
1424 static struct platform_driver s3c64xx_spi_driver = {
1425 	.driver = {
1426 		.name	= "s3c64xx-spi",
1427 		.pm = &s3c64xx_spi_pm,
1428 		.of_match_table = of_match_ptr(s3c64xx_spi_dt_match),
1429 	},
1430 	.probe = s3c64xx_spi_probe,
1431 	.remove = s3c64xx_spi_remove,
1432 	.id_table = s3c64xx_spi_driver_ids,
1433 };
1434 MODULE_ALIAS("platform:s3c64xx-spi");
1435 
1436 module_platform_driver(s3c64xx_spi_driver);
1437 
1438 MODULE_AUTHOR("Jaswinder Singh <jassi.brar@samsung.com>");
1439 MODULE_DESCRIPTION("S3C64XX SPI Controller Driver");
1440 MODULE_LICENSE("GPL");
1441