xref: /openbmc/linux/drivers/spi/spi-s3c64xx.c (revision 275876e2)
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/interrupt.h>
23 #include <linux/delay.h>
24 #include <linux/clk.h>
25 #include <linux/dma-mapping.h>
26 #include <linux/dmaengine.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 <linux/platform_data/spi-s3c64xx.h>
35 
36 #define MAX_SPI_PORTS		3
37 #define S3C64XX_SPI_QUIRK_POLL		(1 << 0)
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 #define is_polling(x)	(x->port_conf->quirks & S3C64XX_SPI_QUIRK_POLL)
130 
131 #define RXBUSY    (1<<2)
132 #define TXBUSY    (1<<3)
133 
134 struct s3c64xx_spi_dma_data {
135 	struct dma_chan *ch;
136 	enum dma_transfer_direction direction;
137 	unsigned int dmach;
138 };
139 
140 /**
141  * struct s3c64xx_spi_info - SPI Controller hardware info
142  * @fifo_lvl_mask: Bit-mask for {TX|RX}_FIFO_LVL bits in SPI_STATUS register.
143  * @rx_lvl_offset: Bit offset of RX_FIFO_LVL bits in SPI_STATUS regiter.
144  * @tx_st_done: Bit offset of TX_DONE bit in SPI_STATUS regiter.
145  * @high_speed: True, if the controller supports HIGH_SPEED_EN bit.
146  * @clk_from_cmu: True, if the controller does not include a clock mux and
147  *	prescaler unit.
148  *
149  * The Samsung s3c64xx SPI controller are used on various Samsung SoC's but
150  * differ in some aspects such as the size of the fifo and spi bus clock
151  * setup. Such differences are specified to the driver using this structure
152  * which is provided as driver data to the driver.
153  */
154 struct s3c64xx_spi_port_config {
155 	int	fifo_lvl_mask[MAX_SPI_PORTS];
156 	int	rx_lvl_offset;
157 	int	tx_st_done;
158 	int	quirks;
159 	bool	high_speed;
160 	bool	clk_from_cmu;
161 };
162 
163 /**
164  * struct s3c64xx_spi_driver_data - Runtime info holder for SPI driver.
165  * @clk: Pointer to the spi clock.
166  * @src_clk: Pointer to the clock used to generate SPI signals.
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 platform_device          *pdev;
187 	struct spi_master               *master;
188 	struct s3c64xx_spi_info  *cntrlr_info;
189 	struct spi_device               *tgl_spi;
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 s3c64xx_spi_port_config	*port_conf;
199 	unsigned int			port_id;
200 };
201 
202 static void flush_fifo(struct s3c64xx_spi_driver_data *sdd)
203 {
204 	void __iomem *regs = sdd->regs;
205 	unsigned long loops;
206 	u32 val;
207 
208 	writel(0, regs + S3C64XX_SPI_PACKET_CNT);
209 
210 	val = readl(regs + S3C64XX_SPI_CH_CFG);
211 	val &= ~(S3C64XX_SPI_CH_RXCH_ON | S3C64XX_SPI_CH_TXCH_ON);
212 	writel(val, regs + S3C64XX_SPI_CH_CFG);
213 
214 	val = readl(regs + S3C64XX_SPI_CH_CFG);
215 	val |= S3C64XX_SPI_CH_SW_RST;
216 	val &= ~S3C64XX_SPI_CH_HS_EN;
217 	writel(val, regs + S3C64XX_SPI_CH_CFG);
218 
219 	/* Flush TxFIFO*/
220 	loops = msecs_to_loops(1);
221 	do {
222 		val = readl(regs + S3C64XX_SPI_STATUS);
223 	} while (TX_FIFO_LVL(val, sdd) && loops--);
224 
225 	if (loops == 0)
226 		dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n");
227 
228 	/* Flush RxFIFO*/
229 	loops = msecs_to_loops(1);
230 	do {
231 		val = readl(regs + S3C64XX_SPI_STATUS);
232 		if (RX_FIFO_LVL(val, sdd))
233 			readl(regs + S3C64XX_SPI_RX_DATA);
234 		else
235 			break;
236 	} while (loops--);
237 
238 	if (loops == 0)
239 		dev_warn(&sdd->pdev->dev, "Timed out flushing RX FIFO\n");
240 
241 	val = readl(regs + S3C64XX_SPI_CH_CFG);
242 	val &= ~S3C64XX_SPI_CH_SW_RST;
243 	writel(val, regs + S3C64XX_SPI_CH_CFG);
244 
245 	val = readl(regs + S3C64XX_SPI_MODE_CFG);
246 	val &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
247 	writel(val, regs + S3C64XX_SPI_MODE_CFG);
248 }
249 
250 static void s3c64xx_spi_dmacb(void *data)
251 {
252 	struct s3c64xx_spi_driver_data *sdd;
253 	struct s3c64xx_spi_dma_data *dma = data;
254 	unsigned long flags;
255 
256 	if (dma->direction == DMA_DEV_TO_MEM)
257 		sdd = container_of(data,
258 			struct s3c64xx_spi_driver_data, rx_dma);
259 	else
260 		sdd = container_of(data,
261 			struct s3c64xx_spi_driver_data, tx_dma);
262 
263 	spin_lock_irqsave(&sdd->lock, flags);
264 
265 	if (dma->direction == DMA_DEV_TO_MEM) {
266 		sdd->state &= ~RXBUSY;
267 		if (!(sdd->state & TXBUSY))
268 			complete(&sdd->xfer_completion);
269 	} else {
270 		sdd->state &= ~TXBUSY;
271 		if (!(sdd->state & RXBUSY))
272 			complete(&sdd->xfer_completion);
273 	}
274 
275 	spin_unlock_irqrestore(&sdd->lock, flags);
276 }
277 
278 static void prepare_dma(struct s3c64xx_spi_dma_data *dma,
279 			struct sg_table *sgt)
280 {
281 	struct s3c64xx_spi_driver_data *sdd;
282 	struct dma_slave_config config;
283 	struct dma_async_tx_descriptor *desc;
284 
285 	memset(&config, 0, sizeof(config));
286 
287 	if (dma->direction == DMA_DEV_TO_MEM) {
288 		sdd = container_of((void *)dma,
289 			struct s3c64xx_spi_driver_data, rx_dma);
290 		config.direction = dma->direction;
291 		config.src_addr = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
292 		config.src_addr_width = sdd->cur_bpw / 8;
293 		config.src_maxburst = 1;
294 		dmaengine_slave_config(dma->ch, &config);
295 	} else {
296 		sdd = container_of((void *)dma,
297 			struct s3c64xx_spi_driver_data, tx_dma);
298 		config.direction = dma->direction;
299 		config.dst_addr = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
300 		config.dst_addr_width = sdd->cur_bpw / 8;
301 		config.dst_maxburst = 1;
302 		dmaengine_slave_config(dma->ch, &config);
303 	}
304 
305 	desc = dmaengine_prep_slave_sg(dma->ch, sgt->sgl, sgt->nents,
306 				       dma->direction, DMA_PREP_INTERRUPT);
307 
308 	desc->callback = s3c64xx_spi_dmacb;
309 	desc->callback_param = dma;
310 
311 	dmaengine_submit(desc);
312 	dma_async_issue_pending(dma->ch);
313 }
314 
315 static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
316 {
317 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
318 	dma_filter_fn filter = sdd->cntrlr_info->filter;
319 	struct device *dev = &sdd->pdev->dev;
320 	dma_cap_mask_t mask;
321 	int ret;
322 
323 	if (!is_polling(sdd)) {
324 		dma_cap_zero(mask);
325 		dma_cap_set(DMA_SLAVE, mask);
326 
327 		/* Acquire DMA channels */
328 		sdd->rx_dma.ch = dma_request_slave_channel_compat(mask, filter,
329 				   (void *)sdd->rx_dma.dmach, dev, "rx");
330 		if (!sdd->rx_dma.ch) {
331 			dev_err(dev, "Failed to get RX DMA channel\n");
332 			ret = -EBUSY;
333 			goto out;
334 		}
335 		spi->dma_rx = sdd->rx_dma.ch;
336 
337 		sdd->tx_dma.ch = dma_request_slave_channel_compat(mask, filter,
338 				   (void *)sdd->tx_dma.dmach, dev, "tx");
339 		if (!sdd->tx_dma.ch) {
340 			dev_err(dev, "Failed to get TX DMA channel\n");
341 			ret = -EBUSY;
342 			goto out_rx;
343 		}
344 		spi->dma_tx = sdd->tx_dma.ch;
345 	}
346 
347 	ret = pm_runtime_get_sync(&sdd->pdev->dev);
348 	if (ret < 0) {
349 		dev_err(dev, "Failed to enable device: %d\n", ret);
350 		goto out_tx;
351 	}
352 
353 	return 0;
354 
355 out_tx:
356 	dma_release_channel(sdd->tx_dma.ch);
357 out_rx:
358 	dma_release_channel(sdd->rx_dma.ch);
359 out:
360 	return ret;
361 }
362 
363 static int s3c64xx_spi_unprepare_transfer(struct spi_master *spi)
364 {
365 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
366 
367 	/* Free DMA channels */
368 	if (!is_polling(sdd)) {
369 		dma_release_channel(sdd->rx_dma.ch);
370 		dma_release_channel(sdd->tx_dma.ch);
371 	}
372 
373 	pm_runtime_put(&sdd->pdev->dev);
374 	return 0;
375 }
376 
377 static bool s3c64xx_spi_can_dma(struct spi_master *master,
378 				struct spi_device *spi,
379 				struct spi_transfer *xfer)
380 {
381 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
382 
383 	return xfer->len > (FIFO_LVL_MASK(sdd) >> 1) + 1;
384 }
385 
386 static void enable_datapath(struct s3c64xx_spi_driver_data *sdd,
387 				struct spi_device *spi,
388 				struct spi_transfer *xfer, int dma_mode)
389 {
390 	void __iomem *regs = sdd->regs;
391 	u32 modecfg, chcfg;
392 
393 	modecfg = readl(regs + S3C64XX_SPI_MODE_CFG);
394 	modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
395 
396 	chcfg = readl(regs + S3C64XX_SPI_CH_CFG);
397 	chcfg &= ~S3C64XX_SPI_CH_TXCH_ON;
398 
399 	if (dma_mode) {
400 		chcfg &= ~S3C64XX_SPI_CH_RXCH_ON;
401 	} else {
402 		/* Always shift in data in FIFO, even if xfer is Tx only,
403 		 * this helps setting PCKT_CNT value for generating clocks
404 		 * as exactly needed.
405 		 */
406 		chcfg |= S3C64XX_SPI_CH_RXCH_ON;
407 		writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
408 					| S3C64XX_SPI_PACKET_CNT_EN,
409 					regs + S3C64XX_SPI_PACKET_CNT);
410 	}
411 
412 	if (xfer->tx_buf != NULL) {
413 		sdd->state |= TXBUSY;
414 		chcfg |= S3C64XX_SPI_CH_TXCH_ON;
415 		if (dma_mode) {
416 			modecfg |= S3C64XX_SPI_MODE_TXDMA_ON;
417 			prepare_dma(&sdd->tx_dma, &xfer->tx_sg);
418 		} else {
419 			switch (sdd->cur_bpw) {
420 			case 32:
421 				iowrite32_rep(regs + S3C64XX_SPI_TX_DATA,
422 					xfer->tx_buf, xfer->len / 4);
423 				break;
424 			case 16:
425 				iowrite16_rep(regs + S3C64XX_SPI_TX_DATA,
426 					xfer->tx_buf, xfer->len / 2);
427 				break;
428 			default:
429 				iowrite8_rep(regs + S3C64XX_SPI_TX_DATA,
430 					xfer->tx_buf, xfer->len);
431 				break;
432 			}
433 		}
434 	}
435 
436 	if (xfer->rx_buf != NULL) {
437 		sdd->state |= RXBUSY;
438 
439 		if (sdd->port_conf->high_speed && sdd->cur_speed >= 30000000UL
440 					&& !(sdd->cur_mode & SPI_CPHA))
441 			chcfg |= S3C64XX_SPI_CH_HS_EN;
442 
443 		if (dma_mode) {
444 			modecfg |= S3C64XX_SPI_MODE_RXDMA_ON;
445 			chcfg |= S3C64XX_SPI_CH_RXCH_ON;
446 			writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
447 					| S3C64XX_SPI_PACKET_CNT_EN,
448 					regs + S3C64XX_SPI_PACKET_CNT);
449 			prepare_dma(&sdd->rx_dma, &xfer->rx_sg);
450 		}
451 	}
452 
453 	writel(modecfg, regs + S3C64XX_SPI_MODE_CFG);
454 	writel(chcfg, regs + S3C64XX_SPI_CH_CFG);
455 }
456 
457 static u32 s3c64xx_spi_wait_for_timeout(struct s3c64xx_spi_driver_data *sdd,
458 					int timeout_ms)
459 {
460 	void __iomem *regs = sdd->regs;
461 	unsigned long val = 1;
462 	u32 status;
463 
464 	/* max fifo depth available */
465 	u32 max_fifo = (FIFO_LVL_MASK(sdd) >> 1) + 1;
466 
467 	if (timeout_ms)
468 		val = msecs_to_loops(timeout_ms);
469 
470 	do {
471 		status = readl(regs + S3C64XX_SPI_STATUS);
472 	} while (RX_FIFO_LVL(status, sdd) < max_fifo && --val);
473 
474 	/* return the actual received data length */
475 	return RX_FIFO_LVL(status, sdd);
476 }
477 
478 static int wait_for_dma(struct s3c64xx_spi_driver_data *sdd,
479 			struct spi_transfer *xfer)
480 {
481 	void __iomem *regs = sdd->regs;
482 	unsigned long val;
483 	u32 status;
484 	int ms;
485 
486 	/* millisecs to xfer 'len' bytes @ 'cur_speed' */
487 	ms = xfer->len * 8 * 1000 / sdd->cur_speed;
488 	ms += 10; /* some tolerance */
489 
490 	val = msecs_to_jiffies(ms) + 10;
491 	val = wait_for_completion_timeout(&sdd->xfer_completion, val);
492 
493 	/*
494 	 * If the previous xfer was completed within timeout, then
495 	 * proceed further else return -EIO.
496 	 * DmaTx returns after simply writing data in the FIFO,
497 	 * w/o waiting for real transmission on the bus to finish.
498 	 * DmaRx returns only after Dma read data from FIFO which
499 	 * needs bus transmission to finish, so we don't worry if
500 	 * Xfer involved Rx(with or without Tx).
501 	 */
502 	if (val && !xfer->rx_buf) {
503 		val = msecs_to_loops(10);
504 		status = readl(regs + S3C64XX_SPI_STATUS);
505 		while ((TX_FIFO_LVL(status, sdd)
506 			|| !S3C64XX_SPI_ST_TX_DONE(status, sdd))
507 		       && --val) {
508 			cpu_relax();
509 			status = readl(regs + S3C64XX_SPI_STATUS);
510 		}
511 
512 	}
513 
514 	/* If timed out while checking rx/tx status return error */
515 	if (!val)
516 		return -EIO;
517 
518 	return 0;
519 }
520 
521 static int wait_for_pio(struct s3c64xx_spi_driver_data *sdd,
522 			struct spi_transfer *xfer)
523 {
524 	void __iomem *regs = sdd->regs;
525 	unsigned long val;
526 	u32 status;
527 	int loops;
528 	u32 cpy_len;
529 	u8 *buf;
530 	int ms;
531 
532 	/* millisecs to xfer 'len' bytes @ 'cur_speed' */
533 	ms = xfer->len * 8 * 1000 / sdd->cur_speed;
534 	ms += 10; /* some tolerance */
535 
536 	val = msecs_to_loops(ms);
537 	do {
538 		status = readl(regs + S3C64XX_SPI_STATUS);
539 	} while (RX_FIFO_LVL(status, sdd) < xfer->len && --val);
540 
541 
542 	/* If it was only Tx */
543 	if (!xfer->rx_buf) {
544 		sdd->state &= ~TXBUSY;
545 		return 0;
546 	}
547 
548 	/*
549 	 * If the receive length is bigger than the controller fifo
550 	 * size, calculate the loops and read the fifo as many times.
551 	 * loops = length / max fifo size (calculated by using the
552 	 * fifo mask).
553 	 * For any size less than the fifo size the below code is
554 	 * executed atleast once.
555 	 */
556 	loops = xfer->len / ((FIFO_LVL_MASK(sdd) >> 1) + 1);
557 	buf = xfer->rx_buf;
558 	do {
559 		/* wait for data to be received in the fifo */
560 		cpy_len = s3c64xx_spi_wait_for_timeout(sdd,
561 						       (loops ? ms : 0));
562 
563 		switch (sdd->cur_bpw) {
564 		case 32:
565 			ioread32_rep(regs + S3C64XX_SPI_RX_DATA,
566 				     buf, cpy_len / 4);
567 			break;
568 		case 16:
569 			ioread16_rep(regs + S3C64XX_SPI_RX_DATA,
570 				     buf, cpy_len / 2);
571 			break;
572 		default:
573 			ioread8_rep(regs + S3C64XX_SPI_RX_DATA,
574 				    buf, cpy_len);
575 			break;
576 		}
577 
578 		buf = buf + cpy_len;
579 	} while (loops--);
580 	sdd->state &= ~RXBUSY;
581 
582 	return 0;
583 }
584 
585 static void s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
586 {
587 	void __iomem *regs = sdd->regs;
588 	u32 val;
589 
590 	/* Disable Clock */
591 	if (sdd->port_conf->clk_from_cmu) {
592 		clk_disable_unprepare(sdd->src_clk);
593 	} else {
594 		val = readl(regs + S3C64XX_SPI_CLK_CFG);
595 		val &= ~S3C64XX_SPI_ENCLK_ENABLE;
596 		writel(val, regs + S3C64XX_SPI_CLK_CFG);
597 	}
598 
599 	/* Set Polarity and Phase */
600 	val = readl(regs + S3C64XX_SPI_CH_CFG);
601 	val &= ~(S3C64XX_SPI_CH_SLAVE |
602 			S3C64XX_SPI_CPOL_L |
603 			S3C64XX_SPI_CPHA_B);
604 
605 	if (sdd->cur_mode & SPI_CPOL)
606 		val |= S3C64XX_SPI_CPOL_L;
607 
608 	if (sdd->cur_mode & SPI_CPHA)
609 		val |= S3C64XX_SPI_CPHA_B;
610 
611 	writel(val, regs + S3C64XX_SPI_CH_CFG);
612 
613 	/* Set Channel & DMA Mode */
614 	val = readl(regs + S3C64XX_SPI_MODE_CFG);
615 	val &= ~(S3C64XX_SPI_MODE_BUS_TSZ_MASK
616 			| S3C64XX_SPI_MODE_CH_TSZ_MASK);
617 
618 	switch (sdd->cur_bpw) {
619 	case 32:
620 		val |= S3C64XX_SPI_MODE_BUS_TSZ_WORD;
621 		val |= S3C64XX_SPI_MODE_CH_TSZ_WORD;
622 		break;
623 	case 16:
624 		val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD;
625 		val |= S3C64XX_SPI_MODE_CH_TSZ_HALFWORD;
626 		break;
627 	default:
628 		val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE;
629 		val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE;
630 		break;
631 	}
632 
633 	writel(val, regs + S3C64XX_SPI_MODE_CFG);
634 
635 	if (sdd->port_conf->clk_from_cmu) {
636 		/* Configure Clock */
637 		/* There is half-multiplier before the SPI */
638 		clk_set_rate(sdd->src_clk, sdd->cur_speed * 2);
639 		/* Enable Clock */
640 		clk_prepare_enable(sdd->src_clk);
641 	} else {
642 		/* Configure Clock */
643 		val = readl(regs + S3C64XX_SPI_CLK_CFG);
644 		val &= ~S3C64XX_SPI_PSR_MASK;
645 		val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / 2 - 1)
646 				& S3C64XX_SPI_PSR_MASK);
647 		writel(val, regs + S3C64XX_SPI_CLK_CFG);
648 
649 		/* Enable Clock */
650 		val = readl(regs + S3C64XX_SPI_CLK_CFG);
651 		val |= S3C64XX_SPI_ENCLK_ENABLE;
652 		writel(val, regs + S3C64XX_SPI_CLK_CFG);
653 	}
654 }
655 
656 #define XFER_DMAADDR_INVALID DMA_BIT_MASK(32)
657 
658 static int s3c64xx_spi_prepare_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 
665 	/* If Master's(controller) state differs from that needed by Slave */
666 	if (sdd->cur_speed != spi->max_speed_hz
667 			|| sdd->cur_mode != spi->mode
668 			|| sdd->cur_bpw != spi->bits_per_word) {
669 		sdd->cur_bpw = spi->bits_per_word;
670 		sdd->cur_speed = spi->max_speed_hz;
671 		sdd->cur_mode = spi->mode;
672 		s3c64xx_spi_config(sdd);
673 	}
674 
675 	/* Configure feedback delay */
676 	writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK);
677 
678 	return 0;
679 }
680 
681 static int s3c64xx_spi_transfer_one(struct spi_master *master,
682 				    struct spi_device *spi,
683 				    struct spi_transfer *xfer)
684 {
685 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
686 	int status;
687 	u32 speed;
688 	u8 bpw;
689 	unsigned long flags;
690 	int use_dma;
691 
692 	reinit_completion(&sdd->xfer_completion);
693 
694 	/* Only BPW and Speed may change across transfers */
695 	bpw = xfer->bits_per_word;
696 	speed = xfer->speed_hz ? : spi->max_speed_hz;
697 
698 	if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) {
699 		sdd->cur_bpw = bpw;
700 		sdd->cur_speed = speed;
701 		s3c64xx_spi_config(sdd);
702 	}
703 
704 	/* Polling method for xfers not bigger than FIFO capacity */
705 	use_dma = 0;
706 	if (!is_polling(sdd) &&
707 	    (sdd->rx_dma.ch && sdd->tx_dma.ch &&
708 	     (xfer->len > ((FIFO_LVL_MASK(sdd) >> 1) + 1))))
709 		use_dma = 1;
710 
711 	spin_lock_irqsave(&sdd->lock, flags);
712 
713 	/* Pending only which is to be done */
714 	sdd->state &= ~RXBUSY;
715 	sdd->state &= ~TXBUSY;
716 
717 	enable_datapath(sdd, spi, xfer, use_dma);
718 
719 	/* Start the signals */
720 	writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
721 
722 	spin_unlock_irqrestore(&sdd->lock, flags);
723 
724 	if (use_dma)
725 		status = wait_for_dma(sdd, xfer);
726 	else
727 		status = wait_for_pio(sdd, xfer);
728 
729 	if (status) {
730 		dev_err(&spi->dev, "I/O Error: rx-%d tx-%d res:rx-%c tx-%c len-%d\n",
731 			xfer->rx_buf ? 1 : 0, xfer->tx_buf ? 1 : 0,
732 			(sdd->state & RXBUSY) ? 'f' : 'p',
733 			(sdd->state & TXBUSY) ? 'f' : 'p',
734 			xfer->len);
735 
736 		if (use_dma) {
737 			if (xfer->tx_buf != NULL
738 			    && (sdd->state & TXBUSY))
739 				dmaengine_terminate_all(sdd->tx_dma.ch);
740 			if (xfer->rx_buf != NULL
741 			    && (sdd->state & RXBUSY))
742 				dmaengine_terminate_all(sdd->rx_dma.ch);
743 		}
744 	} else {
745 		flush_fifo(sdd);
746 	}
747 
748 	return status;
749 }
750 
751 static struct s3c64xx_spi_csinfo *s3c64xx_get_slave_ctrldata(
752 				struct spi_device *spi)
753 {
754 	struct s3c64xx_spi_csinfo *cs;
755 	struct device_node *slave_np, *data_np = NULL;
756 	u32 fb_delay = 0;
757 
758 	slave_np = spi->dev.of_node;
759 	if (!slave_np) {
760 		dev_err(&spi->dev, "device node not found\n");
761 		return ERR_PTR(-EINVAL);
762 	}
763 
764 	data_np = of_get_child_by_name(slave_np, "controller-data");
765 	if (!data_np) {
766 		dev_err(&spi->dev, "child node 'controller-data' not found\n");
767 		return ERR_PTR(-EINVAL);
768 	}
769 
770 	cs = kzalloc(sizeof(*cs), GFP_KERNEL);
771 	if (!cs) {
772 		of_node_put(data_np);
773 		return ERR_PTR(-ENOMEM);
774 	}
775 
776 	of_property_read_u32(data_np, "samsung,spi-feedback-delay", &fb_delay);
777 	cs->fb_delay = fb_delay;
778 	of_node_put(data_np);
779 	return cs;
780 }
781 
782 /*
783  * Here we only check the validity of requested configuration
784  * and save the configuration in a local data-structure.
785  * The controller is actually configured only just before we
786  * get a message to transfer.
787  */
788 static int s3c64xx_spi_setup(struct spi_device *spi)
789 {
790 	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
791 	struct s3c64xx_spi_driver_data *sdd;
792 	struct s3c64xx_spi_info *sci;
793 	int err;
794 
795 	sdd = spi_master_get_devdata(spi->master);
796 	if (spi->dev.of_node) {
797 		cs = s3c64xx_get_slave_ctrldata(spi);
798 		spi->controller_data = cs;
799 	} else if (cs) {
800 		/* On non-DT platforms the SPI core will set spi->cs_gpio
801 		 * to -ENOENT. The GPIO pin used to drive the chip select
802 		 * is defined by using platform data so spi->cs_gpio value
803 		 * has to be override to have the proper GPIO pin number.
804 		 */
805 		spi->cs_gpio = cs->line;
806 	}
807 
808 	if (IS_ERR_OR_NULL(cs)) {
809 		dev_err(&spi->dev, "No CS for SPI(%d)\n", spi->chip_select);
810 		return -ENODEV;
811 	}
812 
813 	if (!spi_get_ctldata(spi)) {
814 		if (gpio_is_valid(spi->cs_gpio)) {
815 			err = gpio_request_one(spi->cs_gpio, GPIOF_OUT_INIT_HIGH,
816 					       dev_name(&spi->dev));
817 			if (err) {
818 				dev_err(&spi->dev,
819 					"Failed to get /CS gpio [%d]: %d\n",
820 					spi->cs_gpio, err);
821 				goto err_gpio_req;
822 			}
823 		}
824 
825 		spi_set_ctldata(spi, cs);
826 	}
827 
828 	sci = sdd->cntrlr_info;
829 
830 	pm_runtime_get_sync(&sdd->pdev->dev);
831 
832 	/* Check if we can provide the requested rate */
833 	if (!sdd->port_conf->clk_from_cmu) {
834 		u32 psr, speed;
835 
836 		/* Max possible */
837 		speed = clk_get_rate(sdd->src_clk) / 2 / (0 + 1);
838 
839 		if (spi->max_speed_hz > speed)
840 			spi->max_speed_hz = speed;
841 
842 		psr = clk_get_rate(sdd->src_clk) / 2 / spi->max_speed_hz - 1;
843 		psr &= S3C64XX_SPI_PSR_MASK;
844 		if (psr == S3C64XX_SPI_PSR_MASK)
845 			psr--;
846 
847 		speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
848 		if (spi->max_speed_hz < speed) {
849 			if (psr+1 < S3C64XX_SPI_PSR_MASK) {
850 				psr++;
851 			} else {
852 				err = -EINVAL;
853 				goto setup_exit;
854 			}
855 		}
856 
857 		speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
858 		if (spi->max_speed_hz >= speed) {
859 			spi->max_speed_hz = speed;
860 		} else {
861 			dev_err(&spi->dev, "Can't set %dHz transfer speed\n",
862 				spi->max_speed_hz);
863 			err = -EINVAL;
864 			goto setup_exit;
865 		}
866 	}
867 
868 	pm_runtime_put(&sdd->pdev->dev);
869 	writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
870 	return 0;
871 
872 setup_exit:
873 	pm_runtime_put(&sdd->pdev->dev);
874 	/* setup() returns with device de-selected */
875 	writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
876 
877 	if (gpio_is_valid(spi->cs_gpio))
878 		gpio_free(spi->cs_gpio);
879 	spi_set_ctldata(spi, NULL);
880 
881 err_gpio_req:
882 	if (spi->dev.of_node)
883 		kfree(cs);
884 
885 	return err;
886 }
887 
888 static void s3c64xx_spi_cleanup(struct spi_device *spi)
889 {
890 	struct s3c64xx_spi_csinfo *cs = spi_get_ctldata(spi);
891 
892 	if (gpio_is_valid(spi->cs_gpio)) {
893 		gpio_free(spi->cs_gpio);
894 		if (spi->dev.of_node)
895 			kfree(cs);
896 		else {
897 			/* On non-DT platforms, the SPI core sets
898 			 * spi->cs_gpio to -ENOENT and .setup()
899 			 * overrides it with the GPIO pin value
900 			 * passed using platform data.
901 			 */
902 			spi->cs_gpio = -ENOENT;
903 		}
904 	}
905 
906 	spi_set_ctldata(spi, NULL);
907 }
908 
909 static irqreturn_t s3c64xx_spi_irq(int irq, void *data)
910 {
911 	struct s3c64xx_spi_driver_data *sdd = data;
912 	struct spi_master *spi = sdd->master;
913 	unsigned int val, clr = 0;
914 
915 	val = readl(sdd->regs + S3C64XX_SPI_STATUS);
916 
917 	if (val & S3C64XX_SPI_ST_RX_OVERRUN_ERR) {
918 		clr = S3C64XX_SPI_PND_RX_OVERRUN_CLR;
919 		dev_err(&spi->dev, "RX overrun\n");
920 	}
921 	if (val & S3C64XX_SPI_ST_RX_UNDERRUN_ERR) {
922 		clr |= S3C64XX_SPI_PND_RX_UNDERRUN_CLR;
923 		dev_err(&spi->dev, "RX underrun\n");
924 	}
925 	if (val & S3C64XX_SPI_ST_TX_OVERRUN_ERR) {
926 		clr |= S3C64XX_SPI_PND_TX_OVERRUN_CLR;
927 		dev_err(&spi->dev, "TX overrun\n");
928 	}
929 	if (val & S3C64XX_SPI_ST_TX_UNDERRUN_ERR) {
930 		clr |= S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
931 		dev_err(&spi->dev, "TX underrun\n");
932 	}
933 
934 	/* Clear the pending irq by setting and then clearing it */
935 	writel(clr, sdd->regs + S3C64XX_SPI_PENDING_CLR);
936 	writel(0, sdd->regs + S3C64XX_SPI_PENDING_CLR);
937 
938 	return IRQ_HANDLED;
939 }
940 
941 static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd, int channel)
942 {
943 	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
944 	void __iomem *regs = sdd->regs;
945 	unsigned int val;
946 
947 	sdd->cur_speed = 0;
948 
949 	writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
950 
951 	/* Disable Interrupts - we use Polling if not DMA mode */
952 	writel(0, regs + S3C64XX_SPI_INT_EN);
953 
954 	if (!sdd->port_conf->clk_from_cmu)
955 		writel(sci->src_clk_nr << S3C64XX_SPI_CLKSEL_SRCSHFT,
956 				regs + S3C64XX_SPI_CLK_CFG);
957 	writel(0, regs + S3C64XX_SPI_MODE_CFG);
958 	writel(0, regs + S3C64XX_SPI_PACKET_CNT);
959 
960 	/* Clear any irq pending bits, should set and clear the bits */
961 	val = S3C64XX_SPI_PND_RX_OVERRUN_CLR |
962 		S3C64XX_SPI_PND_RX_UNDERRUN_CLR |
963 		S3C64XX_SPI_PND_TX_OVERRUN_CLR |
964 		S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
965 	writel(val, regs + S3C64XX_SPI_PENDING_CLR);
966 	writel(0, regs + S3C64XX_SPI_PENDING_CLR);
967 
968 	writel(0, regs + S3C64XX_SPI_SWAP_CFG);
969 
970 	val = readl(regs + S3C64XX_SPI_MODE_CFG);
971 	val &= ~S3C64XX_SPI_MODE_4BURST;
972 	val &= ~(S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
973 	val |= (S3C64XX_SPI_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
974 	writel(val, regs + S3C64XX_SPI_MODE_CFG);
975 
976 	flush_fifo(sdd);
977 }
978 
979 #ifdef CONFIG_OF
980 static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
981 {
982 	struct s3c64xx_spi_info *sci;
983 	u32 temp;
984 
985 	sci = devm_kzalloc(dev, sizeof(*sci), GFP_KERNEL);
986 	if (!sci)
987 		return ERR_PTR(-ENOMEM);
988 
989 	if (of_property_read_u32(dev->of_node, "samsung,spi-src-clk", &temp)) {
990 		dev_warn(dev, "spi bus clock parent not specified, using clock at index 0 as parent\n");
991 		sci->src_clk_nr = 0;
992 	} else {
993 		sci->src_clk_nr = temp;
994 	}
995 
996 	if (of_property_read_u32(dev->of_node, "num-cs", &temp)) {
997 		dev_warn(dev, "number of chip select lines not specified, assuming 1 chip select line\n");
998 		sci->num_cs = 1;
999 	} else {
1000 		sci->num_cs = temp;
1001 	}
1002 
1003 	return sci;
1004 }
1005 #else
1006 static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
1007 {
1008 	return dev_get_platdata(dev);
1009 }
1010 #endif
1011 
1012 static const struct of_device_id s3c64xx_spi_dt_match[];
1013 
1014 static inline struct s3c64xx_spi_port_config *s3c64xx_spi_get_port_config(
1015 						struct platform_device *pdev)
1016 {
1017 #ifdef CONFIG_OF
1018 	if (pdev->dev.of_node) {
1019 		const struct of_device_id *match;
1020 		match = of_match_node(s3c64xx_spi_dt_match, pdev->dev.of_node);
1021 		return (struct s3c64xx_spi_port_config *)match->data;
1022 	}
1023 #endif
1024 	return (struct s3c64xx_spi_port_config *)
1025 			 platform_get_device_id(pdev)->driver_data;
1026 }
1027 
1028 static int s3c64xx_spi_probe(struct platform_device *pdev)
1029 {
1030 	struct resource	*mem_res;
1031 	struct resource	*res;
1032 	struct s3c64xx_spi_driver_data *sdd;
1033 	struct s3c64xx_spi_info *sci = dev_get_platdata(&pdev->dev);
1034 	struct spi_master *master;
1035 	int ret, irq;
1036 	char clk_name[16];
1037 
1038 	if (!sci && pdev->dev.of_node) {
1039 		sci = s3c64xx_spi_parse_dt(&pdev->dev);
1040 		if (IS_ERR(sci))
1041 			return PTR_ERR(sci);
1042 	}
1043 
1044 	if (!sci) {
1045 		dev_err(&pdev->dev, "platform_data missing!\n");
1046 		return -ENODEV;
1047 	}
1048 
1049 	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1050 	if (mem_res == NULL) {
1051 		dev_err(&pdev->dev, "Unable to get SPI MEM resource\n");
1052 		return -ENXIO;
1053 	}
1054 
1055 	irq = platform_get_irq(pdev, 0);
1056 	if (irq < 0) {
1057 		dev_warn(&pdev->dev, "Failed to get IRQ: %d\n", irq);
1058 		return irq;
1059 	}
1060 
1061 	master = spi_alloc_master(&pdev->dev,
1062 				sizeof(struct s3c64xx_spi_driver_data));
1063 	if (master == NULL) {
1064 		dev_err(&pdev->dev, "Unable to allocate SPI Master\n");
1065 		return -ENOMEM;
1066 	}
1067 
1068 	platform_set_drvdata(pdev, master);
1069 
1070 	sdd = spi_master_get_devdata(master);
1071 	sdd->port_conf = s3c64xx_spi_get_port_config(pdev);
1072 	sdd->master = master;
1073 	sdd->cntrlr_info = sci;
1074 	sdd->pdev = pdev;
1075 	sdd->sfr_start = mem_res->start;
1076 	if (pdev->dev.of_node) {
1077 		ret = of_alias_get_id(pdev->dev.of_node, "spi");
1078 		if (ret < 0) {
1079 			dev_err(&pdev->dev, "failed to get alias id, errno %d\n",
1080 				ret);
1081 			goto err0;
1082 		}
1083 		sdd->port_id = ret;
1084 	} else {
1085 		sdd->port_id = pdev->id;
1086 	}
1087 
1088 	sdd->cur_bpw = 8;
1089 
1090 	if (!sdd->pdev->dev.of_node) {
1091 		res = platform_get_resource(pdev, IORESOURCE_DMA,  0);
1092 		if (!res) {
1093 			dev_warn(&pdev->dev, "Unable to get SPI tx dma resource. Switching to poll mode\n");
1094 			sdd->port_conf->quirks = S3C64XX_SPI_QUIRK_POLL;
1095 		} else
1096 			sdd->tx_dma.dmach = res->start;
1097 
1098 		res = platform_get_resource(pdev, IORESOURCE_DMA,  1);
1099 		if (!res) {
1100 			dev_warn(&pdev->dev, "Unable to get SPI rx dma resource. Switching to poll mode\n");
1101 			sdd->port_conf->quirks = S3C64XX_SPI_QUIRK_POLL;
1102 		} else
1103 			sdd->rx_dma.dmach = res->start;
1104 	}
1105 
1106 	sdd->tx_dma.direction = DMA_MEM_TO_DEV;
1107 	sdd->rx_dma.direction = DMA_DEV_TO_MEM;
1108 
1109 	master->dev.of_node = pdev->dev.of_node;
1110 	master->bus_num = sdd->port_id;
1111 	master->setup = s3c64xx_spi_setup;
1112 	master->cleanup = s3c64xx_spi_cleanup;
1113 	master->prepare_transfer_hardware = s3c64xx_spi_prepare_transfer;
1114 	master->prepare_message = s3c64xx_spi_prepare_message;
1115 	master->transfer_one = s3c64xx_spi_transfer_one;
1116 	master->unprepare_transfer_hardware = s3c64xx_spi_unprepare_transfer;
1117 	master->num_chipselect = sci->num_cs;
1118 	master->dma_alignment = 8;
1119 	master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) |
1120 					SPI_BPW_MASK(8);
1121 	/* the spi->mode bits understood by this driver: */
1122 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1123 	master->auto_runtime_pm = true;
1124 	if (!is_polling(sdd))
1125 		master->can_dma = s3c64xx_spi_can_dma;
1126 
1127 	sdd->regs = devm_ioremap_resource(&pdev->dev, mem_res);
1128 	if (IS_ERR(sdd->regs)) {
1129 		ret = PTR_ERR(sdd->regs);
1130 		goto err0;
1131 	}
1132 
1133 	if (sci->cfg_gpio && sci->cfg_gpio()) {
1134 		dev_err(&pdev->dev, "Unable to config gpio\n");
1135 		ret = -EBUSY;
1136 		goto err0;
1137 	}
1138 
1139 	/* Setup clocks */
1140 	sdd->clk = devm_clk_get(&pdev->dev, "spi");
1141 	if (IS_ERR(sdd->clk)) {
1142 		dev_err(&pdev->dev, "Unable to acquire clock 'spi'\n");
1143 		ret = PTR_ERR(sdd->clk);
1144 		goto err0;
1145 	}
1146 
1147 	if (clk_prepare_enable(sdd->clk)) {
1148 		dev_err(&pdev->dev, "Couldn't enable clock 'spi'\n");
1149 		ret = -EBUSY;
1150 		goto err0;
1151 	}
1152 
1153 	sprintf(clk_name, "spi_busclk%d", sci->src_clk_nr);
1154 	sdd->src_clk = devm_clk_get(&pdev->dev, clk_name);
1155 	if (IS_ERR(sdd->src_clk)) {
1156 		dev_err(&pdev->dev,
1157 			"Unable to acquire clock '%s'\n", clk_name);
1158 		ret = PTR_ERR(sdd->src_clk);
1159 		goto err2;
1160 	}
1161 
1162 	if (clk_prepare_enable(sdd->src_clk)) {
1163 		dev_err(&pdev->dev, "Couldn't enable clock '%s'\n", clk_name);
1164 		ret = -EBUSY;
1165 		goto err2;
1166 	}
1167 
1168 	/* Setup Deufult Mode */
1169 	s3c64xx_spi_hwinit(sdd, sdd->port_id);
1170 
1171 	spin_lock_init(&sdd->lock);
1172 	init_completion(&sdd->xfer_completion);
1173 
1174 	ret = devm_request_irq(&pdev->dev, irq, s3c64xx_spi_irq, 0,
1175 				"spi-s3c64xx", sdd);
1176 	if (ret != 0) {
1177 		dev_err(&pdev->dev, "Failed to request IRQ %d: %d\n",
1178 			irq, ret);
1179 		goto err3;
1180 	}
1181 
1182 	writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
1183 	       S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
1184 	       sdd->regs + S3C64XX_SPI_INT_EN);
1185 
1186 	pm_runtime_set_active(&pdev->dev);
1187 	pm_runtime_enable(&pdev->dev);
1188 
1189 	ret = devm_spi_register_master(&pdev->dev, master);
1190 	if (ret != 0) {
1191 		dev_err(&pdev->dev, "cannot register SPI master: %d\n", ret);
1192 		goto err3;
1193 	}
1194 
1195 	dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d with %d Slaves attached\n",
1196 					sdd->port_id, master->num_chipselect);
1197 	dev_dbg(&pdev->dev, "\tIOmem=[%pR]\tDMA=[Rx-%d, Tx-%d]\n",
1198 					mem_res,
1199 					sdd->rx_dma.dmach, sdd->tx_dma.dmach);
1200 
1201 	return 0;
1202 
1203 err3:
1204 	clk_disable_unprepare(sdd->src_clk);
1205 err2:
1206 	clk_disable_unprepare(sdd->clk);
1207 err0:
1208 	spi_master_put(master);
1209 
1210 	return ret;
1211 }
1212 
1213 static int s3c64xx_spi_remove(struct platform_device *pdev)
1214 {
1215 	struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
1216 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1217 
1218 	pm_runtime_disable(&pdev->dev);
1219 
1220 	writel(0, sdd->regs + S3C64XX_SPI_INT_EN);
1221 
1222 	clk_disable_unprepare(sdd->src_clk);
1223 
1224 	clk_disable_unprepare(sdd->clk);
1225 
1226 	return 0;
1227 }
1228 
1229 #ifdef CONFIG_PM_SLEEP
1230 static int s3c64xx_spi_suspend(struct device *dev)
1231 {
1232 	struct spi_master *master = dev_get_drvdata(dev);
1233 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1234 
1235 	int ret = spi_master_suspend(master);
1236 	if (ret)
1237 		return ret;
1238 
1239 	if (!pm_runtime_suspended(dev)) {
1240 		clk_disable_unprepare(sdd->clk);
1241 		clk_disable_unprepare(sdd->src_clk);
1242 	}
1243 
1244 	sdd->cur_speed = 0; /* Output Clock is stopped */
1245 
1246 	return 0;
1247 }
1248 
1249 static int s3c64xx_spi_resume(struct device *dev)
1250 {
1251 	struct spi_master *master = dev_get_drvdata(dev);
1252 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1253 	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1254 
1255 	if (sci->cfg_gpio)
1256 		sci->cfg_gpio();
1257 
1258 	if (!pm_runtime_suspended(dev)) {
1259 		clk_prepare_enable(sdd->src_clk);
1260 		clk_prepare_enable(sdd->clk);
1261 	}
1262 
1263 	s3c64xx_spi_hwinit(sdd, sdd->port_id);
1264 
1265 	return spi_master_resume(master);
1266 }
1267 #endif /* CONFIG_PM_SLEEP */
1268 
1269 #ifdef CONFIG_PM_RUNTIME
1270 static int s3c64xx_spi_runtime_suspend(struct device *dev)
1271 {
1272 	struct spi_master *master = dev_get_drvdata(dev);
1273 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1274 
1275 	clk_disable_unprepare(sdd->clk);
1276 	clk_disable_unprepare(sdd->src_clk);
1277 
1278 	return 0;
1279 }
1280 
1281 static int s3c64xx_spi_runtime_resume(struct device *dev)
1282 {
1283 	struct spi_master *master = dev_get_drvdata(dev);
1284 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1285 	int ret;
1286 
1287 	ret = clk_prepare_enable(sdd->src_clk);
1288 	if (ret != 0)
1289 		return ret;
1290 
1291 	ret = clk_prepare_enable(sdd->clk);
1292 	if (ret != 0) {
1293 		clk_disable_unprepare(sdd->src_clk);
1294 		return ret;
1295 	}
1296 
1297 	return 0;
1298 }
1299 #endif /* CONFIG_PM_RUNTIME */
1300 
1301 static const struct dev_pm_ops s3c64xx_spi_pm = {
1302 	SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume)
1303 	SET_RUNTIME_PM_OPS(s3c64xx_spi_runtime_suspend,
1304 			   s3c64xx_spi_runtime_resume, NULL)
1305 };
1306 
1307 static struct s3c64xx_spi_port_config s3c2443_spi_port_config = {
1308 	.fifo_lvl_mask	= { 0x7f },
1309 	.rx_lvl_offset	= 13,
1310 	.tx_st_done	= 21,
1311 	.high_speed	= true,
1312 };
1313 
1314 static struct s3c64xx_spi_port_config s3c6410_spi_port_config = {
1315 	.fifo_lvl_mask	= { 0x7f, 0x7F },
1316 	.rx_lvl_offset	= 13,
1317 	.tx_st_done	= 21,
1318 };
1319 
1320 static struct s3c64xx_spi_port_config s5pv210_spi_port_config = {
1321 	.fifo_lvl_mask	= { 0x1ff, 0x7F },
1322 	.rx_lvl_offset	= 15,
1323 	.tx_st_done	= 25,
1324 	.high_speed	= true,
1325 };
1326 
1327 static struct s3c64xx_spi_port_config exynos4_spi_port_config = {
1328 	.fifo_lvl_mask	= { 0x1ff, 0x7F, 0x7F },
1329 	.rx_lvl_offset	= 15,
1330 	.tx_st_done	= 25,
1331 	.high_speed	= true,
1332 	.clk_from_cmu	= true,
1333 };
1334 
1335 static struct s3c64xx_spi_port_config exynos5440_spi_port_config = {
1336 	.fifo_lvl_mask	= { 0x1ff },
1337 	.rx_lvl_offset	= 15,
1338 	.tx_st_done	= 25,
1339 	.high_speed	= true,
1340 	.clk_from_cmu	= true,
1341 	.quirks		= S3C64XX_SPI_QUIRK_POLL,
1342 };
1343 
1344 static struct platform_device_id s3c64xx_spi_driver_ids[] = {
1345 	{
1346 		.name		= "s3c2443-spi",
1347 		.driver_data	= (kernel_ulong_t)&s3c2443_spi_port_config,
1348 	}, {
1349 		.name		= "s3c6410-spi",
1350 		.driver_data	= (kernel_ulong_t)&s3c6410_spi_port_config,
1351 	}, {
1352 		.name		= "s5pv210-spi",
1353 		.driver_data	= (kernel_ulong_t)&s5pv210_spi_port_config,
1354 	}, {
1355 		.name		= "exynos4210-spi",
1356 		.driver_data	= (kernel_ulong_t)&exynos4_spi_port_config,
1357 	},
1358 	{ },
1359 };
1360 
1361 static const struct of_device_id s3c64xx_spi_dt_match[] = {
1362 	{ .compatible = "samsung,s3c2443-spi",
1363 			.data = (void *)&s3c2443_spi_port_config,
1364 	},
1365 	{ .compatible = "samsung,s3c6410-spi",
1366 			.data = (void *)&s3c6410_spi_port_config,
1367 	},
1368 	{ .compatible = "samsung,s5pv210-spi",
1369 			.data = (void *)&s5pv210_spi_port_config,
1370 	},
1371 	{ .compatible = "samsung,exynos4210-spi",
1372 			.data = (void *)&exynos4_spi_port_config,
1373 	},
1374 	{ .compatible = "samsung,exynos5440-spi",
1375 			.data = (void *)&exynos5440_spi_port_config,
1376 	},
1377 	{ },
1378 };
1379 MODULE_DEVICE_TABLE(of, s3c64xx_spi_dt_match);
1380 
1381 static struct platform_driver s3c64xx_spi_driver = {
1382 	.driver = {
1383 		.name	= "s3c64xx-spi",
1384 		.owner = THIS_MODULE,
1385 		.pm = &s3c64xx_spi_pm,
1386 		.of_match_table = of_match_ptr(s3c64xx_spi_dt_match),
1387 	},
1388 	.probe = s3c64xx_spi_probe,
1389 	.remove = s3c64xx_spi_remove,
1390 	.id_table = s3c64xx_spi_driver_ids,
1391 };
1392 MODULE_ALIAS("platform:s3c64xx-spi");
1393 
1394 module_platform_driver(s3c64xx_spi_driver);
1395 
1396 MODULE_AUTHOR("Jaswinder Singh <jassi.brar@samsung.com>");
1397 MODULE_DESCRIPTION("S3C64XX SPI Controller Driver");
1398 MODULE_LICENSE("GPL");
1399