xref: /linux/drivers/spi/spi-s3c64xx.c (revision b14132797d8041a42e03f4ffa1e722da1425adfb)
1 /*
2  * Copyright (C) 2009 Samsung Electronics Ltd.
3  *	Jaswinder Singh <jassi.brar@samsung.com>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  */
15 
16 #include <linux/init.h>
17 #include <linux/module.h>
18 #include <linux/interrupt.h>
19 #include <linux/delay.h>
20 #include <linux/clk.h>
21 #include <linux/dma-mapping.h>
22 #include <linux/dmaengine.h>
23 #include <linux/platform_device.h>
24 #include <linux/pm_runtime.h>
25 #include <linux/spi/spi.h>
26 #include <linux/gpio.h>
27 #include <linux/of.h>
28 #include <linux/of_gpio.h>
29 
30 #include <linux/platform_data/spi-s3c64xx.h>
31 
32 #define MAX_SPI_PORTS		6
33 #define S3C64XX_SPI_QUIRK_POLL		(1 << 0)
34 #define S3C64XX_SPI_QUIRK_CS_AUTO	(1 << 1)
35 
36 /* Registers and bit-fields */
37 
38 #define S3C64XX_SPI_CH_CFG		0x00
39 #define S3C64XX_SPI_CLK_CFG		0x04
40 #define S3C64XX_SPI_MODE_CFG	0x08
41 #define S3C64XX_SPI_SLAVE_SEL	0x0C
42 #define S3C64XX_SPI_INT_EN		0x10
43 #define S3C64XX_SPI_STATUS		0x14
44 #define S3C64XX_SPI_TX_DATA		0x18
45 #define S3C64XX_SPI_RX_DATA		0x1C
46 #define S3C64XX_SPI_PACKET_CNT	0x20
47 #define S3C64XX_SPI_PENDING_CLR	0x24
48 #define S3C64XX_SPI_SWAP_CFG	0x28
49 #define S3C64XX_SPI_FB_CLK		0x2C
50 
51 #define S3C64XX_SPI_CH_HS_EN		(1<<6)	/* High Speed Enable */
52 #define S3C64XX_SPI_CH_SW_RST		(1<<5)
53 #define S3C64XX_SPI_CH_SLAVE		(1<<4)
54 #define S3C64XX_SPI_CPOL_L		(1<<3)
55 #define S3C64XX_SPI_CPHA_B		(1<<2)
56 #define S3C64XX_SPI_CH_RXCH_ON		(1<<1)
57 #define S3C64XX_SPI_CH_TXCH_ON		(1<<0)
58 
59 #define S3C64XX_SPI_CLKSEL_SRCMSK	(3<<9)
60 #define S3C64XX_SPI_CLKSEL_SRCSHFT	9
61 #define S3C64XX_SPI_ENCLK_ENABLE	(1<<8)
62 #define S3C64XX_SPI_PSR_MASK		0xff
63 
64 #define S3C64XX_SPI_MODE_CH_TSZ_BYTE		(0<<29)
65 #define S3C64XX_SPI_MODE_CH_TSZ_HALFWORD	(1<<29)
66 #define S3C64XX_SPI_MODE_CH_TSZ_WORD		(2<<29)
67 #define S3C64XX_SPI_MODE_CH_TSZ_MASK		(3<<29)
68 #define S3C64XX_SPI_MODE_BUS_TSZ_BYTE		(0<<17)
69 #define S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD	(1<<17)
70 #define S3C64XX_SPI_MODE_BUS_TSZ_WORD		(2<<17)
71 #define S3C64XX_SPI_MODE_BUS_TSZ_MASK		(3<<17)
72 #define S3C64XX_SPI_MODE_RXDMA_ON		(1<<2)
73 #define S3C64XX_SPI_MODE_TXDMA_ON		(1<<1)
74 #define S3C64XX_SPI_MODE_4BURST			(1<<0)
75 
76 #define S3C64XX_SPI_SLAVE_AUTO			(1<<1)
77 #define S3C64XX_SPI_SLAVE_SIG_INACT		(1<<0)
78 #define S3C64XX_SPI_SLAVE_NSC_CNT_2		(2<<4)
79 
80 #define S3C64XX_SPI_INT_TRAILING_EN		(1<<6)
81 #define S3C64XX_SPI_INT_RX_OVERRUN_EN		(1<<5)
82 #define S3C64XX_SPI_INT_RX_UNDERRUN_EN		(1<<4)
83 #define S3C64XX_SPI_INT_TX_OVERRUN_EN		(1<<3)
84 #define S3C64XX_SPI_INT_TX_UNDERRUN_EN		(1<<2)
85 #define S3C64XX_SPI_INT_RX_FIFORDY_EN		(1<<1)
86 #define S3C64XX_SPI_INT_TX_FIFORDY_EN		(1<<0)
87 
88 #define S3C64XX_SPI_ST_RX_OVERRUN_ERR		(1<<5)
89 #define S3C64XX_SPI_ST_RX_UNDERRUN_ERR	(1<<4)
90 #define S3C64XX_SPI_ST_TX_OVERRUN_ERR		(1<<3)
91 #define S3C64XX_SPI_ST_TX_UNDERRUN_ERR	(1<<2)
92 #define S3C64XX_SPI_ST_RX_FIFORDY		(1<<1)
93 #define S3C64XX_SPI_ST_TX_FIFORDY		(1<<0)
94 
95 #define S3C64XX_SPI_PACKET_CNT_EN		(1<<16)
96 
97 #define S3C64XX_SPI_PND_TX_UNDERRUN_CLR		(1<<4)
98 #define S3C64XX_SPI_PND_TX_OVERRUN_CLR		(1<<3)
99 #define S3C64XX_SPI_PND_RX_UNDERRUN_CLR		(1<<2)
100 #define S3C64XX_SPI_PND_RX_OVERRUN_CLR		(1<<1)
101 #define S3C64XX_SPI_PND_TRAILING_CLR		(1<<0)
102 
103 #define S3C64XX_SPI_SWAP_RX_HALF_WORD		(1<<7)
104 #define S3C64XX_SPI_SWAP_RX_BYTE		(1<<6)
105 #define S3C64XX_SPI_SWAP_RX_BIT			(1<<5)
106 #define S3C64XX_SPI_SWAP_RX_EN			(1<<4)
107 #define S3C64XX_SPI_SWAP_TX_HALF_WORD		(1<<3)
108 #define S3C64XX_SPI_SWAP_TX_BYTE		(1<<2)
109 #define S3C64XX_SPI_SWAP_TX_BIT			(1<<1)
110 #define S3C64XX_SPI_SWAP_TX_EN			(1<<0)
111 
112 #define S3C64XX_SPI_FBCLK_MSK		(3<<0)
113 
114 #define FIFO_LVL_MASK(i) ((i)->port_conf->fifo_lvl_mask[i->port_id])
115 #define S3C64XX_SPI_ST_TX_DONE(v, i) (((v) & \
116 				(1 << (i)->port_conf->tx_st_done)) ? 1 : 0)
117 #define TX_FIFO_LVL(v, i) (((v) >> 6) & FIFO_LVL_MASK(i))
118 #define RX_FIFO_LVL(v, i) (((v) >> (i)->port_conf->rx_lvl_offset) & \
119 					FIFO_LVL_MASK(i))
120 
121 #define S3C64XX_SPI_MAX_TRAILCNT	0x3ff
122 #define S3C64XX_SPI_TRAILCNT_OFF	19
123 
124 #define S3C64XX_SPI_TRAILCNT		S3C64XX_SPI_MAX_TRAILCNT
125 
126 #define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
127 #define is_polling(x)	(x->port_conf->quirks & S3C64XX_SPI_QUIRK_POLL)
128 
129 #define RXBUSY    (1<<2)
130 #define TXBUSY    (1<<3)
131 
132 struct s3c64xx_spi_dma_data {
133 	struct dma_chan *ch;
134 	enum dma_transfer_direction direction;
135 	unsigned int dmach;
136 };
137 
138 /**
139  * struct s3c64xx_spi_info - SPI Controller hardware info
140  * @fifo_lvl_mask: Bit-mask for {TX|RX}_FIFO_LVL bits in SPI_STATUS register.
141  * @rx_lvl_offset: Bit offset of RX_FIFO_LVL bits in SPI_STATUS regiter.
142  * @tx_st_done: Bit offset of TX_DONE bit in SPI_STATUS regiter.
143  * @high_speed: True, if the controller supports HIGH_SPEED_EN bit.
144  * @clk_from_cmu: True, if the controller does not include a clock mux and
145  *	prescaler unit.
146  *
147  * The Samsung s3c64xx SPI controller are used on various Samsung SoC's but
148  * differ in some aspects such as the size of the fifo and spi bus clock
149  * setup. Such differences are specified to the driver using this structure
150  * which is provided as driver data to the driver.
151  */
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 };
160 
161 /**
162  * struct s3c64xx_spi_driver_data - Runtime info holder for SPI driver.
163  * @clk: Pointer to the spi clock.
164  * @src_clk: Pointer to the clock used to generate SPI signals.
165  * @master: Pointer to the SPI Protocol master.
166  * @cntrlr_info: Platform specific data for the controller this driver manages.
167  * @tgl_spi: Pointer to the last CS left untoggled by the cs_change hint.
168  * @lock: Controller specific lock.
169  * @state: Set of FLAGS to indicate status.
170  * @rx_dmach: Controller's DMA channel for Rx.
171  * @tx_dmach: Controller's DMA channel for Tx.
172  * @sfr_start: BUS address of SPI controller regs.
173  * @regs: Pointer to ioremap'ed controller registers.
174  * @irq: interrupt
175  * @xfer_completion: To indicate completion of xfer task.
176  * @cur_mode: Stores the active configuration of the controller.
177  * @cur_bpw: Stores the active bits per word settings.
178  * @cur_speed: Stores the active xfer clock speed.
179  */
180 struct s3c64xx_spi_driver_data {
181 	void __iomem                    *regs;
182 	struct clk                      *clk;
183 	struct clk                      *src_clk;
184 	struct platform_device          *pdev;
185 	struct spi_master               *master;
186 	struct s3c64xx_spi_info  *cntrlr_info;
187 	struct spi_device               *tgl_spi;
188 	spinlock_t                      lock;
189 	unsigned long                   sfr_start;
190 	struct completion               xfer_completion;
191 	unsigned                        state;
192 	unsigned                        cur_mode, cur_bpw;
193 	unsigned                        cur_speed;
194 	struct s3c64xx_spi_dma_data	rx_dma;
195 	struct s3c64xx_spi_dma_data	tx_dma;
196 	struct s3c64xx_spi_port_config	*port_conf;
197 	unsigned int			port_id;
198 };
199 
200 static void flush_fifo(struct s3c64xx_spi_driver_data *sdd)
201 {
202 	void __iomem *regs = sdd->regs;
203 	unsigned long loops;
204 	u32 val;
205 
206 	writel(0, regs + S3C64XX_SPI_PACKET_CNT);
207 
208 	val = readl(regs + S3C64XX_SPI_CH_CFG);
209 	val &= ~(S3C64XX_SPI_CH_RXCH_ON | S3C64XX_SPI_CH_TXCH_ON);
210 	writel(val, regs + S3C64XX_SPI_CH_CFG);
211 
212 	val = readl(regs + S3C64XX_SPI_CH_CFG);
213 	val |= S3C64XX_SPI_CH_SW_RST;
214 	val &= ~S3C64XX_SPI_CH_HS_EN;
215 	writel(val, regs + S3C64XX_SPI_CH_CFG);
216 
217 	/* Flush TxFIFO*/
218 	loops = msecs_to_loops(1);
219 	do {
220 		val = readl(regs + S3C64XX_SPI_STATUS);
221 	} while (TX_FIFO_LVL(val, sdd) && loops--);
222 
223 	if (loops == 0)
224 		dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n");
225 
226 	/* Flush RxFIFO*/
227 	loops = msecs_to_loops(1);
228 	do {
229 		val = readl(regs + S3C64XX_SPI_STATUS);
230 		if (RX_FIFO_LVL(val, sdd))
231 			readl(regs + S3C64XX_SPI_RX_DATA);
232 		else
233 			break;
234 	} while (loops--);
235 
236 	if (loops == 0)
237 		dev_warn(&sdd->pdev->dev, "Timed out flushing RX FIFO\n");
238 
239 	val = readl(regs + S3C64XX_SPI_CH_CFG);
240 	val &= ~S3C64XX_SPI_CH_SW_RST;
241 	writel(val, regs + S3C64XX_SPI_CH_CFG);
242 
243 	val = readl(regs + S3C64XX_SPI_MODE_CFG);
244 	val &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
245 	writel(val, regs + S3C64XX_SPI_MODE_CFG);
246 }
247 
248 static void s3c64xx_spi_dmacb(void *data)
249 {
250 	struct s3c64xx_spi_driver_data *sdd;
251 	struct s3c64xx_spi_dma_data *dma = data;
252 	unsigned long flags;
253 
254 	if (dma->direction == DMA_DEV_TO_MEM)
255 		sdd = container_of(data,
256 			struct s3c64xx_spi_driver_data, rx_dma);
257 	else
258 		sdd = container_of(data,
259 			struct s3c64xx_spi_driver_data, tx_dma);
260 
261 	spin_lock_irqsave(&sdd->lock, flags);
262 
263 	if (dma->direction == DMA_DEV_TO_MEM) {
264 		sdd->state &= ~RXBUSY;
265 		if (!(sdd->state & TXBUSY))
266 			complete(&sdd->xfer_completion);
267 	} else {
268 		sdd->state &= ~TXBUSY;
269 		if (!(sdd->state & RXBUSY))
270 			complete(&sdd->xfer_completion);
271 	}
272 
273 	spin_unlock_irqrestore(&sdd->lock, flags);
274 }
275 
276 static void prepare_dma(struct s3c64xx_spi_dma_data *dma,
277 			struct sg_table *sgt)
278 {
279 	struct s3c64xx_spi_driver_data *sdd;
280 	struct dma_slave_config config;
281 	struct dma_async_tx_descriptor *desc;
282 
283 	memset(&config, 0, sizeof(config));
284 
285 	if (dma->direction == DMA_DEV_TO_MEM) {
286 		sdd = container_of((void *)dma,
287 			struct s3c64xx_spi_driver_data, rx_dma);
288 		config.direction = dma->direction;
289 		config.src_addr = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
290 		config.src_addr_width = sdd->cur_bpw / 8;
291 		config.src_maxburst = 1;
292 		dmaengine_slave_config(dma->ch, &config);
293 	} else {
294 		sdd = container_of((void *)dma,
295 			struct s3c64xx_spi_driver_data, tx_dma);
296 		config.direction = dma->direction;
297 		config.dst_addr = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
298 		config.dst_addr_width = sdd->cur_bpw / 8;
299 		config.dst_maxburst = 1;
300 		dmaengine_slave_config(dma->ch, &config);
301 	}
302 
303 	desc = dmaengine_prep_slave_sg(dma->ch, sgt->sgl, sgt->nents,
304 				       dma->direction, DMA_PREP_INTERRUPT);
305 
306 	desc->callback = s3c64xx_spi_dmacb;
307 	desc->callback_param = dma;
308 
309 	dmaengine_submit(desc);
310 	dma_async_issue_pending(dma->ch);
311 }
312 
313 static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
314 {
315 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
316 	dma_filter_fn filter = sdd->cntrlr_info->filter;
317 	struct device *dev = &sdd->pdev->dev;
318 	dma_cap_mask_t mask;
319 	int ret;
320 
321 	if (!is_polling(sdd)) {
322 		dma_cap_zero(mask);
323 		dma_cap_set(DMA_SLAVE, mask);
324 
325 		/* Acquire DMA channels */
326 		sdd->rx_dma.ch = dma_request_slave_channel_compat(mask, filter,
327 				   (void *)(long)sdd->rx_dma.dmach, dev, "rx");
328 		if (!sdd->rx_dma.ch) {
329 			dev_err(dev, "Failed to get RX DMA channel\n");
330 			ret = -EBUSY;
331 			goto out;
332 		}
333 		spi->dma_rx = sdd->rx_dma.ch;
334 
335 		sdd->tx_dma.ch = dma_request_slave_channel_compat(mask, filter,
336 				   (void *)(long)sdd->tx_dma.dmach, dev, "tx");
337 		if (!sdd->tx_dma.ch) {
338 			dev_err(dev, "Failed to get TX DMA channel\n");
339 			ret = -EBUSY;
340 			goto out_rx;
341 		}
342 		spi->dma_tx = sdd->tx_dma.ch;
343 	}
344 
345 	return 0;
346 
347 out_rx:
348 	dma_release_channel(sdd->rx_dma.ch);
349 out:
350 	return ret;
351 }
352 
353 static int s3c64xx_spi_unprepare_transfer(struct spi_master *spi)
354 {
355 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
356 
357 	/* Free DMA channels */
358 	if (!is_polling(sdd)) {
359 		dma_release_channel(sdd->rx_dma.ch);
360 		dma_release_channel(sdd->tx_dma.ch);
361 	}
362 
363 	return 0;
364 }
365 
366 static bool s3c64xx_spi_can_dma(struct spi_master *master,
367 				struct spi_device *spi,
368 				struct spi_transfer *xfer)
369 {
370 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
371 
372 	return xfer->len > (FIFO_LVL_MASK(sdd) >> 1) + 1;
373 }
374 
375 static void enable_datapath(struct s3c64xx_spi_driver_data *sdd,
376 				struct spi_device *spi,
377 				struct spi_transfer *xfer, int dma_mode)
378 {
379 	void __iomem *regs = sdd->regs;
380 	u32 modecfg, chcfg;
381 
382 	modecfg = readl(regs + S3C64XX_SPI_MODE_CFG);
383 	modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
384 
385 	chcfg = readl(regs + S3C64XX_SPI_CH_CFG);
386 	chcfg &= ~S3C64XX_SPI_CH_TXCH_ON;
387 
388 	if (dma_mode) {
389 		chcfg &= ~S3C64XX_SPI_CH_RXCH_ON;
390 	} else {
391 		/* Always shift in data in FIFO, even if xfer is Tx only,
392 		 * this helps setting PCKT_CNT value for generating clocks
393 		 * as exactly needed.
394 		 */
395 		chcfg |= S3C64XX_SPI_CH_RXCH_ON;
396 		writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
397 					| S3C64XX_SPI_PACKET_CNT_EN,
398 					regs + S3C64XX_SPI_PACKET_CNT);
399 	}
400 
401 	if (xfer->tx_buf != NULL) {
402 		sdd->state |= TXBUSY;
403 		chcfg |= S3C64XX_SPI_CH_TXCH_ON;
404 		if (dma_mode) {
405 			modecfg |= S3C64XX_SPI_MODE_TXDMA_ON;
406 			prepare_dma(&sdd->tx_dma, &xfer->tx_sg);
407 		} else {
408 			switch (sdd->cur_bpw) {
409 			case 32:
410 				iowrite32_rep(regs + S3C64XX_SPI_TX_DATA,
411 					xfer->tx_buf, xfer->len / 4);
412 				break;
413 			case 16:
414 				iowrite16_rep(regs + S3C64XX_SPI_TX_DATA,
415 					xfer->tx_buf, xfer->len / 2);
416 				break;
417 			default:
418 				iowrite8_rep(regs + S3C64XX_SPI_TX_DATA,
419 					xfer->tx_buf, xfer->len);
420 				break;
421 			}
422 		}
423 	}
424 
425 	if (xfer->rx_buf != NULL) {
426 		sdd->state |= RXBUSY;
427 
428 		if (sdd->port_conf->high_speed && sdd->cur_speed >= 30000000UL
429 					&& !(sdd->cur_mode & SPI_CPHA))
430 			chcfg |= S3C64XX_SPI_CH_HS_EN;
431 
432 		if (dma_mode) {
433 			modecfg |= S3C64XX_SPI_MODE_RXDMA_ON;
434 			chcfg |= S3C64XX_SPI_CH_RXCH_ON;
435 			writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
436 					| S3C64XX_SPI_PACKET_CNT_EN,
437 					regs + S3C64XX_SPI_PACKET_CNT);
438 			prepare_dma(&sdd->rx_dma, &xfer->rx_sg);
439 		}
440 	}
441 
442 	writel(modecfg, regs + S3C64XX_SPI_MODE_CFG);
443 	writel(chcfg, regs + S3C64XX_SPI_CH_CFG);
444 }
445 
446 static u32 s3c64xx_spi_wait_for_timeout(struct s3c64xx_spi_driver_data *sdd,
447 					int timeout_ms)
448 {
449 	void __iomem *regs = sdd->regs;
450 	unsigned long val = 1;
451 	u32 status;
452 
453 	/* max fifo depth available */
454 	u32 max_fifo = (FIFO_LVL_MASK(sdd) >> 1) + 1;
455 
456 	if (timeout_ms)
457 		val = msecs_to_loops(timeout_ms);
458 
459 	do {
460 		status = readl(regs + S3C64XX_SPI_STATUS);
461 	} while (RX_FIFO_LVL(status, sdd) < max_fifo && --val);
462 
463 	/* return the actual received data length */
464 	return RX_FIFO_LVL(status, sdd);
465 }
466 
467 static int wait_for_dma(struct s3c64xx_spi_driver_data *sdd,
468 			struct spi_transfer *xfer)
469 {
470 	void __iomem *regs = sdd->regs;
471 	unsigned long val;
472 	u32 status;
473 	int ms;
474 
475 	/* millisecs to xfer 'len' bytes @ 'cur_speed' */
476 	ms = xfer->len * 8 * 1000 / sdd->cur_speed;
477 	ms += 10; /* some tolerance */
478 
479 	val = msecs_to_jiffies(ms) + 10;
480 	val = wait_for_completion_timeout(&sdd->xfer_completion, val);
481 
482 	/*
483 	 * If the previous xfer was completed within timeout, then
484 	 * proceed further else return -EIO.
485 	 * DmaTx returns after simply writing data in the FIFO,
486 	 * w/o waiting for real transmission on the bus to finish.
487 	 * DmaRx returns only after Dma read data from FIFO which
488 	 * needs bus transmission to finish, so we don't worry if
489 	 * Xfer involved Rx(with or without Tx).
490 	 */
491 	if (val && !xfer->rx_buf) {
492 		val = msecs_to_loops(10);
493 		status = readl(regs + S3C64XX_SPI_STATUS);
494 		while ((TX_FIFO_LVL(status, sdd)
495 			|| !S3C64XX_SPI_ST_TX_DONE(status, sdd))
496 		       && --val) {
497 			cpu_relax();
498 			status = readl(regs + S3C64XX_SPI_STATUS);
499 		}
500 
501 	}
502 
503 	/* If timed out while checking rx/tx status return error */
504 	if (!val)
505 		return -EIO;
506 
507 	return 0;
508 }
509 
510 static int wait_for_pio(struct s3c64xx_spi_driver_data *sdd,
511 			struct spi_transfer *xfer)
512 {
513 	void __iomem *regs = sdd->regs;
514 	unsigned long val;
515 	u32 status;
516 	int loops;
517 	u32 cpy_len;
518 	u8 *buf;
519 	int ms;
520 
521 	/* millisecs to xfer 'len' bytes @ 'cur_speed' */
522 	ms = xfer->len * 8 * 1000 / sdd->cur_speed;
523 	ms += 10; /* some tolerance */
524 
525 	val = msecs_to_loops(ms);
526 	do {
527 		status = readl(regs + S3C64XX_SPI_STATUS);
528 	} while (RX_FIFO_LVL(status, sdd) < xfer->len && --val);
529 
530 
531 	/* If it was only Tx */
532 	if (!xfer->rx_buf) {
533 		sdd->state &= ~TXBUSY;
534 		return 0;
535 	}
536 
537 	/*
538 	 * If the receive length is bigger than the controller fifo
539 	 * size, calculate the loops and read the fifo as many times.
540 	 * loops = length / max fifo size (calculated by using the
541 	 * fifo mask).
542 	 * For any size less than the fifo size the below code is
543 	 * executed atleast once.
544 	 */
545 	loops = xfer->len / ((FIFO_LVL_MASK(sdd) >> 1) + 1);
546 	buf = xfer->rx_buf;
547 	do {
548 		/* wait for data to be received in the fifo */
549 		cpy_len = s3c64xx_spi_wait_for_timeout(sdd,
550 						       (loops ? ms : 0));
551 
552 		switch (sdd->cur_bpw) {
553 		case 32:
554 			ioread32_rep(regs + S3C64XX_SPI_RX_DATA,
555 				     buf, cpy_len / 4);
556 			break;
557 		case 16:
558 			ioread16_rep(regs + S3C64XX_SPI_RX_DATA,
559 				     buf, cpy_len / 2);
560 			break;
561 		default:
562 			ioread8_rep(regs + S3C64XX_SPI_RX_DATA,
563 				    buf, cpy_len);
564 			break;
565 		}
566 
567 		buf = buf + cpy_len;
568 	} while (loops--);
569 	sdd->state &= ~RXBUSY;
570 
571 	return 0;
572 }
573 
574 static void s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
575 {
576 	void __iomem *regs = sdd->regs;
577 	u32 val;
578 
579 	/* Disable Clock */
580 	if (sdd->port_conf->clk_from_cmu) {
581 		clk_disable_unprepare(sdd->src_clk);
582 	} else {
583 		val = readl(regs + S3C64XX_SPI_CLK_CFG);
584 		val &= ~S3C64XX_SPI_ENCLK_ENABLE;
585 		writel(val, regs + S3C64XX_SPI_CLK_CFG);
586 	}
587 
588 	/* Set Polarity and Phase */
589 	val = readl(regs + S3C64XX_SPI_CH_CFG);
590 	val &= ~(S3C64XX_SPI_CH_SLAVE |
591 			S3C64XX_SPI_CPOL_L |
592 			S3C64XX_SPI_CPHA_B);
593 
594 	if (sdd->cur_mode & SPI_CPOL)
595 		val |= S3C64XX_SPI_CPOL_L;
596 
597 	if (sdd->cur_mode & SPI_CPHA)
598 		val |= S3C64XX_SPI_CPHA_B;
599 
600 	writel(val, regs + S3C64XX_SPI_CH_CFG);
601 
602 	/* Set Channel & DMA Mode */
603 	val = readl(regs + S3C64XX_SPI_MODE_CFG);
604 	val &= ~(S3C64XX_SPI_MODE_BUS_TSZ_MASK
605 			| S3C64XX_SPI_MODE_CH_TSZ_MASK);
606 
607 	switch (sdd->cur_bpw) {
608 	case 32:
609 		val |= S3C64XX_SPI_MODE_BUS_TSZ_WORD;
610 		val |= S3C64XX_SPI_MODE_CH_TSZ_WORD;
611 		break;
612 	case 16:
613 		val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD;
614 		val |= S3C64XX_SPI_MODE_CH_TSZ_HALFWORD;
615 		break;
616 	default:
617 		val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE;
618 		val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE;
619 		break;
620 	}
621 
622 	writel(val, regs + S3C64XX_SPI_MODE_CFG);
623 
624 	if (sdd->port_conf->clk_from_cmu) {
625 		/* Configure Clock */
626 		/* There is half-multiplier before the SPI */
627 		clk_set_rate(sdd->src_clk, sdd->cur_speed * 2);
628 		/* Enable Clock */
629 		clk_prepare_enable(sdd->src_clk);
630 	} else {
631 		/* Configure Clock */
632 		val = readl(regs + S3C64XX_SPI_CLK_CFG);
633 		val &= ~S3C64XX_SPI_PSR_MASK;
634 		val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / 2 - 1)
635 				& S3C64XX_SPI_PSR_MASK);
636 		writel(val, regs + S3C64XX_SPI_CLK_CFG);
637 
638 		/* Enable Clock */
639 		val = readl(regs + S3C64XX_SPI_CLK_CFG);
640 		val |= S3C64XX_SPI_ENCLK_ENABLE;
641 		writel(val, regs + S3C64XX_SPI_CLK_CFG);
642 	}
643 }
644 
645 #define XFER_DMAADDR_INVALID DMA_BIT_MASK(32)
646 
647 static int s3c64xx_spi_prepare_message(struct spi_master *master,
648 				       struct spi_message *msg)
649 {
650 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
651 	struct spi_device *spi = msg->spi;
652 	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
653 
654 	/* If Master's(controller) state differs from that needed by Slave */
655 	if (sdd->cur_speed != spi->max_speed_hz
656 			|| sdd->cur_mode != spi->mode
657 			|| sdd->cur_bpw != spi->bits_per_word) {
658 		sdd->cur_bpw = spi->bits_per_word;
659 		sdd->cur_speed = spi->max_speed_hz;
660 		sdd->cur_mode = spi->mode;
661 		s3c64xx_spi_config(sdd);
662 	}
663 
664 	/* Configure feedback delay */
665 	writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK);
666 
667 	return 0;
668 }
669 
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 ? : spi->max_speed_hz;
686 
687 	if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) {
688 		sdd->cur_bpw = bpw;
689 		sdd->cur_speed = speed;
690 		s3c64xx_spi_config(sdd);
691 	}
692 
693 	/* Polling method for xfers not bigger than FIFO capacity */
694 	use_dma = 0;
695 	if (!is_polling(sdd) &&
696 	    (sdd->rx_dma.ch && sdd->tx_dma.ch &&
697 	     (xfer->len > ((FIFO_LVL_MASK(sdd) >> 1) + 1))))
698 		use_dma = 1;
699 
700 	spin_lock_irqsave(&sdd->lock, flags);
701 
702 	/* Pending only which is to be done */
703 	sdd->state &= ~RXBUSY;
704 	sdd->state &= ~TXBUSY;
705 
706 	enable_datapath(sdd, spi, xfer, use_dma);
707 
708 	/* Start the signals */
709 	if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
710 		writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
711 	else
712 		writel(readl(sdd->regs + S3C64XX_SPI_SLAVE_SEL)
713 			| S3C64XX_SPI_SLAVE_AUTO | S3C64XX_SPI_SLAVE_NSC_CNT_2,
714 			sdd->regs + S3C64XX_SPI_SLAVE_SEL);
715 
716 	spin_unlock_irqrestore(&sdd->lock, flags);
717 
718 	if (use_dma)
719 		status = wait_for_dma(sdd, xfer);
720 	else
721 		status = wait_for_pio(sdd, xfer);
722 
723 	if (status) {
724 		dev_err(&spi->dev, "I/O Error: rx-%d tx-%d res:rx-%c tx-%c len-%d\n",
725 			xfer->rx_buf ? 1 : 0, xfer->tx_buf ? 1 : 0,
726 			(sdd->state & RXBUSY) ? 'f' : 'p',
727 			(sdd->state & TXBUSY) ? 'f' : 'p',
728 			xfer->len);
729 
730 		if (use_dma) {
731 			if (xfer->tx_buf != NULL
732 			    && (sdd->state & TXBUSY))
733 				dmaengine_terminate_all(sdd->tx_dma.ch);
734 			if (xfer->rx_buf != NULL
735 			    && (sdd->state & RXBUSY))
736 				dmaengine_terminate_all(sdd->rx_dma.ch);
737 		}
738 	} else {
739 		flush_fifo(sdd);
740 	}
741 
742 	return status;
743 }
744 
745 static struct s3c64xx_spi_csinfo *s3c64xx_get_slave_ctrldata(
746 				struct spi_device *spi)
747 {
748 	struct s3c64xx_spi_csinfo *cs;
749 	struct device_node *slave_np, *data_np = NULL;
750 	u32 fb_delay = 0;
751 
752 	slave_np = spi->dev.of_node;
753 	if (!slave_np) {
754 		dev_err(&spi->dev, "device node not found\n");
755 		return ERR_PTR(-EINVAL);
756 	}
757 
758 	data_np = of_get_child_by_name(slave_np, "controller-data");
759 	if (!data_np) {
760 		dev_err(&spi->dev, "child node 'controller-data' not found\n");
761 		return ERR_PTR(-EINVAL);
762 	}
763 
764 	cs = kzalloc(sizeof(*cs), GFP_KERNEL);
765 	if (!cs) {
766 		of_node_put(data_np);
767 		return ERR_PTR(-ENOMEM);
768 	}
769 
770 	of_property_read_u32(data_np, "samsung,spi-feedback-delay", &fb_delay);
771 	cs->fb_delay = fb_delay;
772 	of_node_put(data_np);
773 	return cs;
774 }
775 
776 /*
777  * Here we only check the validity of requested configuration
778  * and save the configuration in a local data-structure.
779  * The controller is actually configured only just before we
780  * get a message to transfer.
781  */
782 static int s3c64xx_spi_setup(struct spi_device *spi)
783 {
784 	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
785 	struct s3c64xx_spi_driver_data *sdd;
786 	struct s3c64xx_spi_info *sci;
787 	int err;
788 
789 	sdd = spi_master_get_devdata(spi->master);
790 	if (spi->dev.of_node) {
791 		cs = s3c64xx_get_slave_ctrldata(spi);
792 		spi->controller_data = cs;
793 	} else if (cs) {
794 		/* On non-DT platforms the SPI core will set spi->cs_gpio
795 		 * to -ENOENT. The GPIO pin used to drive the chip select
796 		 * is defined by using platform data so spi->cs_gpio value
797 		 * has to be override to have the proper GPIO pin number.
798 		 */
799 		spi->cs_gpio = cs->line;
800 	}
801 
802 	if (IS_ERR_OR_NULL(cs)) {
803 		dev_err(&spi->dev, "No CS for SPI(%d)\n", spi->chip_select);
804 		return -ENODEV;
805 	}
806 
807 	if (!spi_get_ctldata(spi)) {
808 		if (gpio_is_valid(spi->cs_gpio)) {
809 			err = gpio_request_one(spi->cs_gpio, GPIOF_OUT_INIT_HIGH,
810 					       dev_name(&spi->dev));
811 			if (err) {
812 				dev_err(&spi->dev,
813 					"Failed to get /CS gpio [%d]: %d\n",
814 					spi->cs_gpio, err);
815 				goto err_gpio_req;
816 			}
817 		}
818 
819 		spi_set_ctldata(spi, cs);
820 	}
821 
822 	sci = sdd->cntrlr_info;
823 
824 	pm_runtime_get_sync(&sdd->pdev->dev);
825 
826 	/* Check if we can provide the requested rate */
827 	if (!sdd->port_conf->clk_from_cmu) {
828 		u32 psr, speed;
829 
830 		/* Max possible */
831 		speed = clk_get_rate(sdd->src_clk) / 2 / (0 + 1);
832 
833 		if (spi->max_speed_hz > speed)
834 			spi->max_speed_hz = speed;
835 
836 		psr = clk_get_rate(sdd->src_clk) / 2 / spi->max_speed_hz - 1;
837 		psr &= S3C64XX_SPI_PSR_MASK;
838 		if (psr == S3C64XX_SPI_PSR_MASK)
839 			psr--;
840 
841 		speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
842 		if (spi->max_speed_hz < speed) {
843 			if (psr+1 < S3C64XX_SPI_PSR_MASK) {
844 				psr++;
845 			} else {
846 				err = -EINVAL;
847 				goto setup_exit;
848 			}
849 		}
850 
851 		speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
852 		if (spi->max_speed_hz >= speed) {
853 			spi->max_speed_hz = speed;
854 		} else {
855 			dev_err(&spi->dev, "Can't set %dHz transfer speed\n",
856 				spi->max_speed_hz);
857 			err = -EINVAL;
858 			goto setup_exit;
859 		}
860 	}
861 
862 	pm_runtime_put(&sdd->pdev->dev);
863 	if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
864 		writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
865 	return 0;
866 
867 setup_exit:
868 	pm_runtime_put(&sdd->pdev->dev);
869 	/* setup() returns with device de-selected */
870 	if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
871 		writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
872 
873 	if (gpio_is_valid(spi->cs_gpio))
874 		gpio_free(spi->cs_gpio);
875 	spi_set_ctldata(spi, NULL);
876 
877 err_gpio_req:
878 	if (spi->dev.of_node)
879 		kfree(cs);
880 
881 	return err;
882 }
883 
884 static void s3c64xx_spi_cleanup(struct spi_device *spi)
885 {
886 	struct s3c64xx_spi_csinfo *cs = spi_get_ctldata(spi);
887 
888 	if (gpio_is_valid(spi->cs_gpio)) {
889 		gpio_free(spi->cs_gpio);
890 		if (spi->dev.of_node)
891 			kfree(cs);
892 		else {
893 			/* On non-DT platforms, the SPI core sets
894 			 * spi->cs_gpio to -ENOENT and .setup()
895 			 * overrides it with the GPIO pin value
896 			 * passed using platform data.
897 			 */
898 			spi->cs_gpio = -ENOENT;
899 		}
900 	}
901 
902 	spi_set_ctldata(spi, NULL);
903 }
904 
905 static irqreturn_t s3c64xx_spi_irq(int irq, void *data)
906 {
907 	struct s3c64xx_spi_driver_data *sdd = data;
908 	struct spi_master *spi = sdd->master;
909 	unsigned int val, clr = 0;
910 
911 	val = readl(sdd->regs + S3C64XX_SPI_STATUS);
912 
913 	if (val & S3C64XX_SPI_ST_RX_OVERRUN_ERR) {
914 		clr = S3C64XX_SPI_PND_RX_OVERRUN_CLR;
915 		dev_err(&spi->dev, "RX overrun\n");
916 	}
917 	if (val & S3C64XX_SPI_ST_RX_UNDERRUN_ERR) {
918 		clr |= S3C64XX_SPI_PND_RX_UNDERRUN_CLR;
919 		dev_err(&spi->dev, "RX underrun\n");
920 	}
921 	if (val & S3C64XX_SPI_ST_TX_OVERRUN_ERR) {
922 		clr |= S3C64XX_SPI_PND_TX_OVERRUN_CLR;
923 		dev_err(&spi->dev, "TX overrun\n");
924 	}
925 	if (val & S3C64XX_SPI_ST_TX_UNDERRUN_ERR) {
926 		clr |= S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
927 		dev_err(&spi->dev, "TX underrun\n");
928 	}
929 
930 	/* Clear the pending irq by setting and then clearing it */
931 	writel(clr, sdd->regs + S3C64XX_SPI_PENDING_CLR);
932 	writel(0, sdd->regs + S3C64XX_SPI_PENDING_CLR);
933 
934 	return IRQ_HANDLED;
935 }
936 
937 static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd, int channel)
938 {
939 	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
940 	void __iomem *regs = sdd->regs;
941 	unsigned int val;
942 
943 	sdd->cur_speed = 0;
944 
945 	if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
946 		writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
947 
948 	/* Disable Interrupts - we use Polling if not DMA mode */
949 	writel(0, regs + S3C64XX_SPI_INT_EN);
950 
951 	if (!sdd->port_conf->clk_from_cmu)
952 		writel(sci->src_clk_nr << S3C64XX_SPI_CLKSEL_SRCSHFT,
953 				regs + S3C64XX_SPI_CLK_CFG);
954 	writel(0, regs + S3C64XX_SPI_MODE_CFG);
955 	writel(0, regs + S3C64XX_SPI_PACKET_CNT);
956 
957 	/* Clear any irq pending bits, should set and clear the bits */
958 	val = S3C64XX_SPI_PND_RX_OVERRUN_CLR |
959 		S3C64XX_SPI_PND_RX_UNDERRUN_CLR |
960 		S3C64XX_SPI_PND_TX_OVERRUN_CLR |
961 		S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
962 	writel(val, regs + S3C64XX_SPI_PENDING_CLR);
963 	writel(0, regs + S3C64XX_SPI_PENDING_CLR);
964 
965 	writel(0, regs + S3C64XX_SPI_SWAP_CFG);
966 
967 	val = readl(regs + S3C64XX_SPI_MODE_CFG);
968 	val &= ~S3C64XX_SPI_MODE_4BURST;
969 	val &= ~(S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
970 	val |= (S3C64XX_SPI_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
971 	writel(val, regs + S3C64XX_SPI_MODE_CFG);
972 
973 	flush_fifo(sdd);
974 }
975 
976 #ifdef CONFIG_OF
977 static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
978 {
979 	struct s3c64xx_spi_info *sci;
980 	u32 temp;
981 
982 	sci = devm_kzalloc(dev, sizeof(*sci), GFP_KERNEL);
983 	if (!sci)
984 		return ERR_PTR(-ENOMEM);
985 
986 	if (of_property_read_u32(dev->of_node, "samsung,spi-src-clk", &temp)) {
987 		dev_warn(dev, "spi bus clock parent not specified, using clock at index 0 as parent\n");
988 		sci->src_clk_nr = 0;
989 	} else {
990 		sci->src_clk_nr = temp;
991 	}
992 
993 	if (of_property_read_u32(dev->of_node, "num-cs", &temp)) {
994 		dev_warn(dev, "number of chip select lines not specified, assuming 1 chip select line\n");
995 		sci->num_cs = 1;
996 	} else {
997 		sci->num_cs = temp;
998 	}
999 
1000 	return sci;
1001 }
1002 #else
1003 static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
1004 {
1005 	return dev_get_platdata(dev);
1006 }
1007 #endif
1008 
1009 static const struct of_device_id s3c64xx_spi_dt_match[];
1010 
1011 static inline struct s3c64xx_spi_port_config *s3c64xx_spi_get_port_config(
1012 						struct platform_device *pdev)
1013 {
1014 #ifdef CONFIG_OF
1015 	if (pdev->dev.of_node) {
1016 		const struct of_device_id *match;
1017 		match = of_match_node(s3c64xx_spi_dt_match, pdev->dev.of_node);
1018 		return (struct s3c64xx_spi_port_config *)match->data;
1019 	}
1020 #endif
1021 	return (struct s3c64xx_spi_port_config *)
1022 			 platform_get_device_id(pdev)->driver_data;
1023 }
1024 
1025 static int s3c64xx_spi_probe(struct platform_device *pdev)
1026 {
1027 	struct resource	*mem_res;
1028 	struct resource	*res;
1029 	struct s3c64xx_spi_driver_data *sdd;
1030 	struct s3c64xx_spi_info *sci = dev_get_platdata(&pdev->dev);
1031 	struct spi_master *master;
1032 	int ret, irq;
1033 	char clk_name[16];
1034 
1035 	if (!sci && pdev->dev.of_node) {
1036 		sci = s3c64xx_spi_parse_dt(&pdev->dev);
1037 		if (IS_ERR(sci))
1038 			return PTR_ERR(sci);
1039 	}
1040 
1041 	if (!sci) {
1042 		dev_err(&pdev->dev, "platform_data missing!\n");
1043 		return -ENODEV;
1044 	}
1045 
1046 	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1047 	if (mem_res == NULL) {
1048 		dev_err(&pdev->dev, "Unable to get SPI MEM resource\n");
1049 		return -ENXIO;
1050 	}
1051 
1052 	irq = platform_get_irq(pdev, 0);
1053 	if (irq < 0) {
1054 		dev_warn(&pdev->dev, "Failed to get IRQ: %d\n", irq);
1055 		return irq;
1056 	}
1057 
1058 	master = spi_alloc_master(&pdev->dev,
1059 				sizeof(struct s3c64xx_spi_driver_data));
1060 	if (master == NULL) {
1061 		dev_err(&pdev->dev, "Unable to allocate SPI Master\n");
1062 		return -ENOMEM;
1063 	}
1064 
1065 	platform_set_drvdata(pdev, master);
1066 
1067 	sdd = spi_master_get_devdata(master);
1068 	sdd->port_conf = s3c64xx_spi_get_port_config(pdev);
1069 	sdd->master = master;
1070 	sdd->cntrlr_info = sci;
1071 	sdd->pdev = pdev;
1072 	sdd->sfr_start = mem_res->start;
1073 	if (pdev->dev.of_node) {
1074 		ret = of_alias_get_id(pdev->dev.of_node, "spi");
1075 		if (ret < 0) {
1076 			dev_err(&pdev->dev, "failed to get alias id, errno %d\n",
1077 				ret);
1078 			goto err0;
1079 		}
1080 		sdd->port_id = ret;
1081 	} else {
1082 		sdd->port_id = pdev->id;
1083 	}
1084 
1085 	sdd->cur_bpw = 8;
1086 
1087 	if (!sdd->pdev->dev.of_node) {
1088 		res = platform_get_resource(pdev, IORESOURCE_DMA,  0);
1089 		if (!res) {
1090 			dev_warn(&pdev->dev, "Unable to get SPI tx dma resource. Switching to poll mode\n");
1091 			sdd->port_conf->quirks = S3C64XX_SPI_QUIRK_POLL;
1092 		} else
1093 			sdd->tx_dma.dmach = res->start;
1094 
1095 		res = platform_get_resource(pdev, IORESOURCE_DMA,  1);
1096 		if (!res) {
1097 			dev_warn(&pdev->dev, "Unable to get SPI rx dma resource. Switching to poll mode\n");
1098 			sdd->port_conf->quirks = S3C64XX_SPI_QUIRK_POLL;
1099 		} else
1100 			sdd->rx_dma.dmach = res->start;
1101 	}
1102 
1103 	sdd->tx_dma.direction = DMA_MEM_TO_DEV;
1104 	sdd->rx_dma.direction = DMA_DEV_TO_MEM;
1105 
1106 	master->dev.of_node = pdev->dev.of_node;
1107 	master->bus_num = sdd->port_id;
1108 	master->setup = s3c64xx_spi_setup;
1109 	master->cleanup = s3c64xx_spi_cleanup;
1110 	master->prepare_transfer_hardware = s3c64xx_spi_prepare_transfer;
1111 	master->prepare_message = s3c64xx_spi_prepare_message;
1112 	master->transfer_one = s3c64xx_spi_transfer_one;
1113 	master->unprepare_transfer_hardware = s3c64xx_spi_unprepare_transfer;
1114 	master->num_chipselect = sci->num_cs;
1115 	master->dma_alignment = 8;
1116 	master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) |
1117 					SPI_BPW_MASK(8);
1118 	/* the spi->mode bits understood by this driver: */
1119 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1120 	master->auto_runtime_pm = true;
1121 	if (!is_polling(sdd))
1122 		master->can_dma = s3c64xx_spi_can_dma;
1123 
1124 	sdd->regs = devm_ioremap_resource(&pdev->dev, mem_res);
1125 	if (IS_ERR(sdd->regs)) {
1126 		ret = PTR_ERR(sdd->regs);
1127 		goto err0;
1128 	}
1129 
1130 	if (sci->cfg_gpio && sci->cfg_gpio()) {
1131 		dev_err(&pdev->dev, "Unable to config gpio\n");
1132 		ret = -EBUSY;
1133 		goto err0;
1134 	}
1135 
1136 	/* Setup clocks */
1137 	sdd->clk = devm_clk_get(&pdev->dev, "spi");
1138 	if (IS_ERR(sdd->clk)) {
1139 		dev_err(&pdev->dev, "Unable to acquire clock 'spi'\n");
1140 		ret = PTR_ERR(sdd->clk);
1141 		goto err0;
1142 	}
1143 
1144 	if (clk_prepare_enable(sdd->clk)) {
1145 		dev_err(&pdev->dev, "Couldn't enable clock 'spi'\n");
1146 		ret = -EBUSY;
1147 		goto err0;
1148 	}
1149 
1150 	sprintf(clk_name, "spi_busclk%d", sci->src_clk_nr);
1151 	sdd->src_clk = devm_clk_get(&pdev->dev, clk_name);
1152 	if (IS_ERR(sdd->src_clk)) {
1153 		dev_err(&pdev->dev,
1154 			"Unable to acquire clock '%s'\n", clk_name);
1155 		ret = PTR_ERR(sdd->src_clk);
1156 		goto err2;
1157 	}
1158 
1159 	if (clk_prepare_enable(sdd->src_clk)) {
1160 		dev_err(&pdev->dev, "Couldn't enable clock '%s'\n", clk_name);
1161 		ret = -EBUSY;
1162 		goto err2;
1163 	}
1164 
1165 	/* Setup Deufult Mode */
1166 	s3c64xx_spi_hwinit(sdd, sdd->port_id);
1167 
1168 	spin_lock_init(&sdd->lock);
1169 	init_completion(&sdd->xfer_completion);
1170 
1171 	ret = devm_request_irq(&pdev->dev, irq, s3c64xx_spi_irq, 0,
1172 				"spi-s3c64xx", sdd);
1173 	if (ret != 0) {
1174 		dev_err(&pdev->dev, "Failed to request IRQ %d: %d\n",
1175 			irq, ret);
1176 		goto err3;
1177 	}
1178 
1179 	writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
1180 	       S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
1181 	       sdd->regs + S3C64XX_SPI_INT_EN);
1182 
1183 	pm_runtime_set_active(&pdev->dev);
1184 	pm_runtime_enable(&pdev->dev);
1185 
1186 	ret = devm_spi_register_master(&pdev->dev, master);
1187 	if (ret != 0) {
1188 		dev_err(&pdev->dev, "cannot register SPI master: %d\n", ret);
1189 		goto err3;
1190 	}
1191 
1192 	dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d with %d Slaves attached\n",
1193 					sdd->port_id, master->num_chipselect);
1194 	dev_dbg(&pdev->dev, "\tIOmem=[%pR]\tFIFO %dbytes\tDMA=[Rx-%d, Tx-%d]\n",
1195 					mem_res, (FIFO_LVL_MASK(sdd) >> 1) + 1,
1196 					sdd->rx_dma.dmach, sdd->tx_dma.dmach);
1197 
1198 	return 0;
1199 
1200 err3:
1201 	clk_disable_unprepare(sdd->src_clk);
1202 err2:
1203 	clk_disable_unprepare(sdd->clk);
1204 err0:
1205 	spi_master_put(master);
1206 
1207 	return ret;
1208 }
1209 
1210 static int s3c64xx_spi_remove(struct platform_device *pdev)
1211 {
1212 	struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
1213 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1214 
1215 	pm_runtime_disable(&pdev->dev);
1216 
1217 	writel(0, sdd->regs + S3C64XX_SPI_INT_EN);
1218 
1219 	clk_disable_unprepare(sdd->src_clk);
1220 
1221 	clk_disable_unprepare(sdd->clk);
1222 
1223 	return 0;
1224 }
1225 
1226 #ifdef CONFIG_PM_SLEEP
1227 static int s3c64xx_spi_suspend(struct device *dev)
1228 {
1229 	struct spi_master *master = dev_get_drvdata(dev);
1230 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1231 
1232 	int ret = spi_master_suspend(master);
1233 	if (ret)
1234 		return ret;
1235 
1236 	if (!pm_runtime_suspended(dev)) {
1237 		clk_disable_unprepare(sdd->clk);
1238 		clk_disable_unprepare(sdd->src_clk);
1239 	}
1240 
1241 	sdd->cur_speed = 0; /* Output Clock is stopped */
1242 
1243 	return 0;
1244 }
1245 
1246 static int s3c64xx_spi_resume(struct device *dev)
1247 {
1248 	struct spi_master *master = dev_get_drvdata(dev);
1249 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1250 	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1251 
1252 	if (sci->cfg_gpio)
1253 		sci->cfg_gpio();
1254 
1255 	if (!pm_runtime_suspended(dev)) {
1256 		clk_prepare_enable(sdd->src_clk);
1257 		clk_prepare_enable(sdd->clk);
1258 	}
1259 
1260 	s3c64xx_spi_hwinit(sdd, sdd->port_id);
1261 
1262 	return spi_master_resume(master);
1263 }
1264 #endif /* CONFIG_PM_SLEEP */
1265 
1266 #ifdef CONFIG_PM
1267 static int s3c64xx_spi_runtime_suspend(struct device *dev)
1268 {
1269 	struct spi_master *master = dev_get_drvdata(dev);
1270 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1271 
1272 	clk_disable_unprepare(sdd->clk);
1273 	clk_disable_unprepare(sdd->src_clk);
1274 
1275 	return 0;
1276 }
1277 
1278 static int s3c64xx_spi_runtime_resume(struct device *dev)
1279 {
1280 	struct spi_master *master = dev_get_drvdata(dev);
1281 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1282 	int ret;
1283 
1284 	ret = clk_prepare_enable(sdd->src_clk);
1285 	if (ret != 0)
1286 		return ret;
1287 
1288 	ret = clk_prepare_enable(sdd->clk);
1289 	if (ret != 0) {
1290 		clk_disable_unprepare(sdd->src_clk);
1291 		return ret;
1292 	}
1293 
1294 	return 0;
1295 }
1296 #endif /* CONFIG_PM */
1297 
1298 static const struct dev_pm_ops s3c64xx_spi_pm = {
1299 	SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume)
1300 	SET_RUNTIME_PM_OPS(s3c64xx_spi_runtime_suspend,
1301 			   s3c64xx_spi_runtime_resume, NULL)
1302 };
1303 
1304 static struct s3c64xx_spi_port_config s3c2443_spi_port_config = {
1305 	.fifo_lvl_mask	= { 0x7f },
1306 	.rx_lvl_offset	= 13,
1307 	.tx_st_done	= 21,
1308 	.high_speed	= true,
1309 };
1310 
1311 static struct s3c64xx_spi_port_config s3c6410_spi_port_config = {
1312 	.fifo_lvl_mask	= { 0x7f, 0x7F },
1313 	.rx_lvl_offset	= 13,
1314 	.tx_st_done	= 21,
1315 };
1316 
1317 static struct s3c64xx_spi_port_config s5pv210_spi_port_config = {
1318 	.fifo_lvl_mask	= { 0x1ff, 0x7F },
1319 	.rx_lvl_offset	= 15,
1320 	.tx_st_done	= 25,
1321 	.high_speed	= true,
1322 };
1323 
1324 static struct s3c64xx_spi_port_config exynos4_spi_port_config = {
1325 	.fifo_lvl_mask	= { 0x1ff, 0x7F, 0x7F },
1326 	.rx_lvl_offset	= 15,
1327 	.tx_st_done	= 25,
1328 	.high_speed	= true,
1329 	.clk_from_cmu	= true,
1330 };
1331 
1332 static struct s3c64xx_spi_port_config exynos5440_spi_port_config = {
1333 	.fifo_lvl_mask	= { 0x1ff },
1334 	.rx_lvl_offset	= 15,
1335 	.tx_st_done	= 25,
1336 	.high_speed	= true,
1337 	.clk_from_cmu	= true,
1338 	.quirks		= S3C64XX_SPI_QUIRK_POLL,
1339 };
1340 
1341 static struct s3c64xx_spi_port_config exynos7_spi_port_config = {
1342 	.fifo_lvl_mask	= { 0x1ff, 0x7F, 0x7F, 0x7F, 0x7F, 0x1ff},
1343 	.rx_lvl_offset	= 15,
1344 	.tx_st_done	= 25,
1345 	.high_speed	= true,
1346 	.clk_from_cmu	= true,
1347 	.quirks		= S3C64XX_SPI_QUIRK_CS_AUTO,
1348 };
1349 
1350 static const struct platform_device_id s3c64xx_spi_driver_ids[] = {
1351 	{
1352 		.name		= "s3c2443-spi",
1353 		.driver_data	= (kernel_ulong_t)&s3c2443_spi_port_config,
1354 	}, {
1355 		.name		= "s3c6410-spi",
1356 		.driver_data	= (kernel_ulong_t)&s3c6410_spi_port_config,
1357 	}, {
1358 		.name		= "s5pv210-spi",
1359 		.driver_data	= (kernel_ulong_t)&s5pv210_spi_port_config,
1360 	}, {
1361 		.name		= "exynos4210-spi",
1362 		.driver_data	= (kernel_ulong_t)&exynos4_spi_port_config,
1363 	},
1364 	{ },
1365 };
1366 
1367 static const struct of_device_id s3c64xx_spi_dt_match[] = {
1368 	{ .compatible = "samsung,s3c2443-spi",
1369 			.data = (void *)&s3c2443_spi_port_config,
1370 	},
1371 	{ .compatible = "samsung,s3c6410-spi",
1372 			.data = (void *)&s3c6410_spi_port_config,
1373 	},
1374 	{ .compatible = "samsung,s5pv210-spi",
1375 			.data = (void *)&s5pv210_spi_port_config,
1376 	},
1377 	{ .compatible = "samsung,exynos4210-spi",
1378 			.data = (void *)&exynos4_spi_port_config,
1379 	},
1380 	{ .compatible = "samsung,exynos5440-spi",
1381 			.data = (void *)&exynos5440_spi_port_config,
1382 	},
1383 	{ .compatible = "samsung,exynos7-spi",
1384 			.data = (void *)&exynos7_spi_port_config,
1385 	},
1386 	{ },
1387 };
1388 MODULE_DEVICE_TABLE(of, s3c64xx_spi_dt_match);
1389 
1390 static struct platform_driver s3c64xx_spi_driver = {
1391 	.driver = {
1392 		.name	= "s3c64xx-spi",
1393 		.pm = &s3c64xx_spi_pm,
1394 		.of_match_table = of_match_ptr(s3c64xx_spi_dt_match),
1395 	},
1396 	.probe = s3c64xx_spi_probe,
1397 	.remove = s3c64xx_spi_remove,
1398 	.id_table = s3c64xx_spi_driver_ids,
1399 };
1400 MODULE_ALIAS("platform:s3c64xx-spi");
1401 
1402 module_platform_driver(s3c64xx_spi_driver);
1403 
1404 MODULE_AUTHOR("Jaswinder Singh <jassi.brar@samsung.com>");
1405 MODULE_DESCRIPTION("S3C64XX SPI Controller Driver");
1406 MODULE_LICENSE("GPL");
1407