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Linux 3.12.39
[linux/fpc-iii.git] / drivers / spi / spi-s3c64xx.c
bloba80376dc3a102d04684f27934a42412be3e851d7
1 /*
2 * Copyright (C) 2009 Samsung Electronics Ltd.
3 * Jaswinder Singh <jassi.brar@samsung.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18 */
19
20 #include <linux/init.h>
21 #include <linux/module.h>
22 #include <linux/workqueue.h>
23 #include <linux/interrupt.h>
24 #include <linux/delay.h>
25 #include <linux/clk.h>
26 #include <linux/dma-mapping.h>
27 #include <linux/dmaengine.h>
28 #include <linux/platform_device.h>
29 #include <linux/pm_runtime.h>
30 #include <linux/spi/spi.h>
31 #include <linux/gpio.h>
32 #include <linux/of.h>
33 #include <linux/of_gpio.h>
34
35 #include <linux/platform_data/spi-s3c64xx.h>
36
37 #ifdef CONFIG_S3C_DMA
38 #include <mach/dma.h>
39 #endif
40
41 #define MAX_SPI_PORTS 3
42 #define S3C64XX_SPI_QUIRK_POLL (1 << 0)
43
44 /* Registers and bit-fields */
45
46 #define S3C64XX_SPI_CH_CFG 0x00
47 #define S3C64XX_SPI_CLK_CFG 0x04
48 #define S3C64XX_SPI_MODE_CFG 0x08
49 #define S3C64XX_SPI_SLAVE_SEL 0x0C
50 #define S3C64XX_SPI_INT_EN 0x10
51 #define S3C64XX_SPI_STATUS 0x14
52 #define S3C64XX_SPI_TX_DATA 0x18
53 #define S3C64XX_SPI_RX_DATA 0x1C
54 #define S3C64XX_SPI_PACKET_CNT 0x20
55 #define S3C64XX_SPI_PENDING_CLR 0x24
56 #define S3C64XX_SPI_SWAP_CFG 0x28
57 #define S3C64XX_SPI_FB_CLK 0x2C
58
59 #define S3C64XX_SPI_CH_HS_EN (1<<6) /* High Speed Enable */
60 #define S3C64XX_SPI_CH_SW_RST (1<<5)
61 #define S3C64XX_SPI_CH_SLAVE (1<<4)
62 #define S3C64XX_SPI_CPOL_L (1<<3)
63 #define S3C64XX_SPI_CPHA_B (1<<2)
64 #define S3C64XX_SPI_CH_RXCH_ON (1<<1)
65 #define S3C64XX_SPI_CH_TXCH_ON (1<<0)
66
67 #define S3C64XX_SPI_CLKSEL_SRCMSK (3<<9)
68 #define S3C64XX_SPI_CLKSEL_SRCSHFT 9
69 #define S3C64XX_SPI_ENCLK_ENABLE (1<<8)
70 #define S3C64XX_SPI_PSR_MASK 0xff
71
72 #define S3C64XX_SPI_MODE_CH_TSZ_BYTE (0<<29)
73 #define S3C64XX_SPI_MODE_CH_TSZ_HALFWORD (1<<29)
74 #define S3C64XX_SPI_MODE_CH_TSZ_WORD (2<<29)
75 #define S3C64XX_SPI_MODE_CH_TSZ_MASK (3<<29)
76 #define S3C64XX_SPI_MODE_BUS_TSZ_BYTE (0<<17)
77 #define S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD (1<<17)
78 #define S3C64XX_SPI_MODE_BUS_TSZ_WORD (2<<17)
79 #define S3C64XX_SPI_MODE_BUS_TSZ_MASK (3<<17)
80 #define S3C64XX_SPI_MODE_RXDMA_ON (1<<2)
81 #define S3C64XX_SPI_MODE_TXDMA_ON (1<<1)
82 #define S3C64XX_SPI_MODE_4BURST (1<<0)
83
84 #define S3C64XX_SPI_SLAVE_AUTO (1<<1)
85 #define S3C64XX_SPI_SLAVE_SIG_INACT (1<<0)
86
87 #define S3C64XX_SPI_INT_TRAILING_EN (1<<6)
88 #define S3C64XX_SPI_INT_RX_OVERRUN_EN (1<<5)
89 #define S3C64XX_SPI_INT_RX_UNDERRUN_EN (1<<4)
90 #define S3C64XX_SPI_INT_TX_OVERRUN_EN (1<<3)
91 #define S3C64XX_SPI_INT_TX_UNDERRUN_EN (1<<2)
92 #define S3C64XX_SPI_INT_RX_FIFORDY_EN (1<<1)
93 #define S3C64XX_SPI_INT_TX_FIFORDY_EN (1<<0)
94
95 #define S3C64XX_SPI_ST_RX_OVERRUN_ERR (1<<5)
96 #define S3C64XX_SPI_ST_RX_UNDERRUN_ERR (1<<4)
97 #define S3C64XX_SPI_ST_TX_OVERRUN_ERR (1<<3)
98 #define S3C64XX_SPI_ST_TX_UNDERRUN_ERR (1<<2)
99 #define S3C64XX_SPI_ST_RX_FIFORDY (1<<1)
100 #define S3C64XX_SPI_ST_TX_FIFORDY (1<<0)
101
102 #define S3C64XX_SPI_PACKET_CNT_EN (1<<16)
103
104 #define S3C64XX_SPI_PND_TX_UNDERRUN_CLR (1<<4)
105 #define S3C64XX_SPI_PND_TX_OVERRUN_CLR (1<<3)
106 #define S3C64XX_SPI_PND_RX_UNDERRUN_CLR (1<<2)
107 #define S3C64XX_SPI_PND_RX_OVERRUN_CLR (1<<1)
108 #define S3C64XX_SPI_PND_TRAILING_CLR (1<<0)
109
110 #define S3C64XX_SPI_SWAP_RX_HALF_WORD (1<<7)
111 #define S3C64XX_SPI_SWAP_RX_BYTE (1<<6)
112 #define S3C64XX_SPI_SWAP_RX_BIT (1<<5)
113 #define S3C64XX_SPI_SWAP_RX_EN (1<<4)
114 #define S3C64XX_SPI_SWAP_TX_HALF_WORD (1<<3)
115 #define S3C64XX_SPI_SWAP_TX_BYTE (1<<2)
116 #define S3C64XX_SPI_SWAP_TX_BIT (1<<1)
117 #define S3C64XX_SPI_SWAP_TX_EN (1<<0)
118
119 #define S3C64XX_SPI_FBCLK_MSK (3<<0)
120
121 #define FIFO_LVL_MASK(i) ((i)->port_conf->fifo_lvl_mask[i->port_id])
122 #define S3C64XX_SPI_ST_TX_DONE(v, i) (((v) & \
123 (1 << (i)->port_conf->tx_st_done)) ? 1 : 0)
124 #define TX_FIFO_LVL(v, i) (((v) >> 6) & FIFO_LVL_MASK(i))
125 #define RX_FIFO_LVL(v, i) (((v) >> (i)->port_conf->rx_lvl_offset) & \
126 FIFO_LVL_MASK(i))
127
128 #define S3C64XX_SPI_MAX_TRAILCNT 0x3ff
129 #define S3C64XX_SPI_TRAILCNT_OFF 19
130
131 #define S3C64XX_SPI_TRAILCNT S3C64XX_SPI_MAX_TRAILCNT
132
133 #define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
134 #define is_polling(x) (x->port_conf->quirks & S3C64XX_SPI_QUIRK_POLL)
135
136 #define RXBUSY (1<<2)
137 #define TXBUSY (1<<3)
138
139 struct s3c64xx_spi_dma_data {
140 struct dma_chan *ch;
141 enum dma_transfer_direction direction;
142 unsigned int dmach;
143 };
144
145 /**
146 * struct s3c64xx_spi_info - SPI Controller hardware info
147 * @fifo_lvl_mask: Bit-mask for {TX|RX}_FIFO_LVL bits in SPI_STATUS register.
148 * @rx_lvl_offset: Bit offset of RX_FIFO_LVL bits in SPI_STATUS regiter.
149 * @tx_st_done: Bit offset of TX_DONE bit in SPI_STATUS regiter.
150 * @high_speed: True, if the controller supports HIGH_SPEED_EN bit.
151 * @clk_from_cmu: True, if the controller does not include a clock mux and
152 * prescaler unit.
153 *
154 * The Samsung s3c64xx SPI controller are used on various Samsung SoC's but
155 * differ in some aspects such as the size of the fifo and spi bus clock
156 * setup. Such differences are specified to the driver using this structure
157 * which is provided as driver data to the driver.
158 */
159 struct s3c64xx_spi_port_config {
160 int fifo_lvl_mask[MAX_SPI_PORTS];
161 int rx_lvl_offset;
162 int tx_st_done;
163 int quirks;
164 bool high_speed;
165 bool clk_from_cmu;
166 };
167
168 /**
169 * struct s3c64xx_spi_driver_data - Runtime info holder for SPI driver.
170 * @clk: Pointer to the spi clock.
171 * @src_clk: Pointer to the clock used to generate SPI signals.
172 * @master: Pointer to the SPI Protocol master.
173 * @cntrlr_info: Platform specific data for the controller this driver manages.
174 * @tgl_spi: Pointer to the last CS left untoggled by the cs_change hint.
175 * @lock: Controller specific lock.
176 * @state: Set of FLAGS to indicate status.
177 * @rx_dmach: Controller's DMA channel for Rx.
178 * @tx_dmach: Controller's DMA channel for Tx.
179 * @sfr_start: BUS address of SPI controller regs.
180 * @regs: Pointer to ioremap'ed controller registers.
181 * @irq: interrupt
182 * @xfer_completion: To indicate completion of xfer task.
183 * @cur_mode: Stores the active configuration of the controller.
184 * @cur_bpw: Stores the active bits per word settings.
185 * @cur_speed: Stores the active xfer clock speed.
186 */
187 struct s3c64xx_spi_driver_data {
188 void __iomem *regs;
189 struct clk *clk;
190 struct clk *src_clk;
191 struct platform_device *pdev;
192 struct spi_master *master;
193 struct s3c64xx_spi_info *cntrlr_info;
194 struct spi_device *tgl_spi;
195 spinlock_t lock;
196 unsigned long sfr_start;
197 struct completion xfer_completion;
198 unsigned state;
199 unsigned cur_mode, cur_bpw;
200 unsigned cur_speed;
201 struct s3c64xx_spi_dma_data rx_dma;
202 struct s3c64xx_spi_dma_data tx_dma;
203 #ifdef CONFIG_S3C_DMA
204 struct samsung_dma_ops *ops;
205 #endif
206 struct s3c64xx_spi_port_config *port_conf;
207 unsigned int port_id;
208 unsigned long gpios[4];
209 bool cs_gpio;
210 };
211
212 static void flush_fifo(struct s3c64xx_spi_driver_data *sdd)
213 {
214 void __iomem *regs = sdd->regs;
215 unsigned long loops;
216 u32 val;
217
218 writel(0, regs + S3C64XX_SPI_PACKET_CNT);
219
220 val = readl(regs + S3C64XX_SPI_CH_CFG);
221 val &= ~(S3C64XX_SPI_CH_RXCH_ON | S3C64XX_SPI_CH_TXCH_ON);
222 writel(val, regs + S3C64XX_SPI_CH_CFG);
223
224 val = readl(regs + S3C64XX_SPI_CH_CFG);
225 val |= S3C64XX_SPI_CH_SW_RST;
226 val &= ~S3C64XX_SPI_CH_HS_EN;
227 writel(val, regs + S3C64XX_SPI_CH_CFG);
228
229 /* Flush TxFIFO*/
230 loops = msecs_to_loops(1);
231 do {
232 val = readl(regs + S3C64XX_SPI_STATUS);
233 } while (TX_FIFO_LVL(val, sdd) && loops--);
234
235 if (loops == 0)
236 dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n");
237
238 /* Flush RxFIFO*/
239 loops = msecs_to_loops(1);
240 do {
241 val = readl(regs + S3C64XX_SPI_STATUS);
242 if (RX_FIFO_LVL(val, sdd))
243 readl(regs + S3C64XX_SPI_RX_DATA);
244 else
245 break;
246 } while (loops--);
247
248 if (loops == 0)
249 dev_warn(&sdd->pdev->dev, "Timed out flushing RX FIFO\n");
250
251 val = readl(regs + S3C64XX_SPI_CH_CFG);
252 val &= ~S3C64XX_SPI_CH_SW_RST;
253 writel(val, regs + S3C64XX_SPI_CH_CFG);
254
255 val = readl(regs + S3C64XX_SPI_MODE_CFG);
256 val &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
257 writel(val, regs + S3C64XX_SPI_MODE_CFG);
258 }
259
260 static void s3c64xx_spi_dmacb(void *data)
261 {
262 struct s3c64xx_spi_driver_data *sdd;
263 struct s3c64xx_spi_dma_data *dma = data;
264 unsigned long flags;
265
266 if (dma->direction == DMA_DEV_TO_MEM)
267 sdd = container_of(data,
268 struct s3c64xx_spi_driver_data, rx_dma);
269 else
270 sdd = container_of(data,
271 struct s3c64xx_spi_driver_data, tx_dma);
272
273 spin_lock_irqsave(&sdd->lock, flags);
274
275 if (dma->direction == DMA_DEV_TO_MEM) {
276 sdd->state &= ~RXBUSY;
277 if (!(sdd->state & TXBUSY))
278 complete(&sdd->xfer_completion);
279 } else {
280 sdd->state &= ~TXBUSY;
281 if (!(sdd->state & RXBUSY))
282 complete(&sdd->xfer_completion);
283 }
284
285 spin_unlock_irqrestore(&sdd->lock, flags);
286 }
287
288 #ifdef CONFIG_S3C_DMA
289 /* FIXME: remove this section once arch/arm/mach-s3c64xx uses dmaengine */
290
291 static struct s3c2410_dma_client s3c64xx_spi_dma_client = {
292 .name = "samsung-spi-dma",
293 };
294
295 static void prepare_dma(struct s3c64xx_spi_dma_data *dma,
296 unsigned len, dma_addr_t buf)
297 {
298 struct s3c64xx_spi_driver_data *sdd;
299 struct samsung_dma_prep info;
300 struct samsung_dma_config config;
301
302 if (dma->direction == DMA_DEV_TO_MEM) {
303 sdd = container_of((void *)dma,
304 struct s3c64xx_spi_driver_data, rx_dma);
305 config.direction = sdd->rx_dma.direction;
306 config.fifo = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
307 config.width = sdd->cur_bpw / 8;
308 sdd->ops->config((enum dma_ch)sdd->rx_dma.ch, &config);
309 } else {
310 sdd = container_of((void *)dma,
311 struct s3c64xx_spi_driver_data, tx_dma);
312 config.direction = sdd->tx_dma.direction;
313 config.fifo = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
314 config.width = sdd->cur_bpw / 8;
315 sdd->ops->config((enum dma_ch)sdd->tx_dma.ch, &config);
316 }
317
318 info.cap = DMA_SLAVE;
319 info.len = len;
320 info.fp = s3c64xx_spi_dmacb;
321 info.fp_param = dma;
322 info.direction = dma->direction;
323 info.buf = buf;
324
325 sdd->ops->prepare((enum dma_ch)dma->ch, &info);
326 sdd->ops->trigger((enum dma_ch)dma->ch);
327 }
328
329 static int acquire_dma(struct s3c64xx_spi_driver_data *sdd)
330 {
331 struct samsung_dma_req req;
332 struct device *dev = &sdd->pdev->dev;
333
334 sdd->ops = samsung_dma_get_ops();
335
336 req.cap = DMA_SLAVE;
337 req.client = &s3c64xx_spi_dma_client;
338
339 sdd->rx_dma.ch = (struct dma_chan *)(unsigned long)sdd->ops->request(
340 sdd->rx_dma.dmach, &req, dev, "rx");
341 sdd->tx_dma.ch = (struct dma_chan *)(unsigned long)sdd->ops->request(
342 sdd->tx_dma.dmach, &req, dev, "tx");
343
344 return 1;
345 }
346
347 static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
348 {
349 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
350
351 /*
352 * If DMA resource was not available during
353 * probe, no need to continue with dma requests
354 * else Acquire DMA channels
355 */
356 while (!is_polling(sdd) && !acquire_dma(sdd))
357 usleep_range(10000, 11000);
358
359 return 0;
360 }
361
362 static int s3c64xx_spi_unprepare_transfer(struct spi_master *spi)
363 {
364 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
365
366 /* Free DMA channels */
367 if (!is_polling(sdd)) {
368 sdd->ops->release((enum dma_ch)sdd->rx_dma.ch,
369 &s3c64xx_spi_dma_client);
370 sdd->ops->release((enum dma_ch)sdd->tx_dma.ch,
371 &s3c64xx_spi_dma_client);
372 }
373
374 return 0;
375 }
376
377 static void s3c64xx_spi_dma_stop(struct s3c64xx_spi_driver_data *sdd,
378 struct s3c64xx_spi_dma_data *dma)
379 {
380 sdd->ops->stop((enum dma_ch)dma->ch);
381 }
382 #else
383
384 static void prepare_dma(struct s3c64xx_spi_dma_data *dma,
385 unsigned len, dma_addr_t buf)
386 {
387 struct s3c64xx_spi_driver_data *sdd;
388 struct dma_slave_config config;
389 struct dma_async_tx_descriptor *desc;
390
391 memset(&config, 0, sizeof(config));
392
393 if (dma->direction == DMA_DEV_TO_MEM) {
394 sdd = container_of((void *)dma,
395 struct s3c64xx_spi_driver_data, rx_dma);
396 config.direction = dma->direction;
397 config.src_addr = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
398 config.src_addr_width = sdd->cur_bpw / 8;
399 config.src_maxburst = 1;
400 dmaengine_slave_config(dma->ch, &config);
401 } else {
402 sdd = container_of((void *)dma,
403 struct s3c64xx_spi_driver_data, tx_dma);
404 config.direction = dma->direction;
405 config.dst_addr = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
406 config.dst_addr_width = sdd->cur_bpw / 8;
407 config.dst_maxburst = 1;
408 dmaengine_slave_config(dma->ch, &config);
409 }
410
411 desc = dmaengine_prep_slave_single(dma->ch, buf, len,
412 dma->direction, DMA_PREP_INTERRUPT);
413
414 desc->callback = s3c64xx_spi_dmacb;
415 desc->callback_param = dma;
416
417 dmaengine_submit(desc);
418 dma_async_issue_pending(dma->ch);
419 }
420
421 static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
422 {
423 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
424 dma_filter_fn filter = sdd->cntrlr_info->filter;
425 struct device *dev = &sdd->pdev->dev;
426 dma_cap_mask_t mask;
427 int ret;
428
429 if (!is_polling(sdd)) {
430 dma_cap_zero(mask);
431 dma_cap_set(DMA_SLAVE, mask);
432
433 /* Acquire DMA channels */
434 sdd->rx_dma.ch = dma_request_slave_channel_compat(mask, filter,
435 (void *)sdd->rx_dma.dmach, dev, "rx");
436 if (!sdd->rx_dma.ch) {
437 dev_err(dev, "Failed to get RX DMA channel\n");
438 ret = -EBUSY;
439 goto out;
440 }
441
442 sdd->tx_dma.ch = dma_request_slave_channel_compat(mask, filter,
443 (void *)sdd->tx_dma.dmach, dev, "tx");
444 if (!sdd->tx_dma.ch) {
445 dev_err(dev, "Failed to get TX DMA channel\n");
446 ret = -EBUSY;
447 goto out_rx;
448 }
449 }
450
451 ret = pm_runtime_get_sync(&sdd->pdev->dev);
452 if (ret < 0) {
453 dev_err(dev, "Failed to enable device: %d\n", ret);
454 goto out_tx;
455 }
456
457 return 0;
458
459 out_tx:
460 dma_release_channel(sdd->tx_dma.ch);
461 out_rx:
462 dma_release_channel(sdd->rx_dma.ch);
463 out:
464 return ret;
465 }
466
467 static int s3c64xx_spi_unprepare_transfer(struct spi_master *spi)
468 {
469 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
470
471 /* Free DMA channels */
472 if (!is_polling(sdd)) {
473 dma_release_channel(sdd->rx_dma.ch);
474 dma_release_channel(sdd->tx_dma.ch);
475 }
476
477 pm_runtime_put(&sdd->pdev->dev);
478 return 0;
479 }
480
481 static void s3c64xx_spi_dma_stop(struct s3c64xx_spi_driver_data *sdd,
482 struct s3c64xx_spi_dma_data *dma)
483 {
484 dmaengine_terminate_all(dma->ch);
485 }
486 #endif
487
488 static void enable_datapath(struct s3c64xx_spi_driver_data *sdd,
489 struct spi_device *spi,
490 struct spi_transfer *xfer, int dma_mode)
491 {
492 void __iomem *regs = sdd->regs;
493 u32 modecfg, chcfg;
494
495 modecfg = readl(regs + S3C64XX_SPI_MODE_CFG);
496 modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
497
498 chcfg = readl(regs + S3C64XX_SPI_CH_CFG);
499 chcfg &= ~S3C64XX_SPI_CH_TXCH_ON;
500
501 if (dma_mode) {
502 chcfg &= ~S3C64XX_SPI_CH_RXCH_ON;
503 } else {
504 /* Always shift in data in FIFO, even if xfer is Tx only,
505 * this helps setting PCKT_CNT value for generating clocks
506 * as exactly needed.
507 */
508 chcfg |= S3C64XX_SPI_CH_RXCH_ON;
509 writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
510 | S3C64XX_SPI_PACKET_CNT_EN,
511 regs + S3C64XX_SPI_PACKET_CNT);
512 }
513
514 if (xfer->tx_buf != NULL) {
515 sdd->state |= TXBUSY;
516 chcfg |= S3C64XX_SPI_CH_TXCH_ON;
517 if (dma_mode) {
518 modecfg |= S3C64XX_SPI_MODE_TXDMA_ON;
519 prepare_dma(&sdd->tx_dma, xfer->len, xfer->tx_dma);
520 } else {
521 switch (sdd->cur_bpw) {
522 case 32:
523 iowrite32_rep(regs + S3C64XX_SPI_TX_DATA,
524 xfer->tx_buf, xfer->len / 4);
525 break;
526 case 16:
527 iowrite16_rep(regs + S3C64XX_SPI_TX_DATA,
528 xfer->tx_buf, xfer->len / 2);
529 break;
530 default:
531 iowrite8_rep(regs + S3C64XX_SPI_TX_DATA,
532 xfer->tx_buf, xfer->len);
533 break;
534 }
535 }
536 }
537
538 if (xfer->rx_buf != NULL) {
539 sdd->state |= RXBUSY;
540
541 if (sdd->port_conf->high_speed && sdd->cur_speed >= 30000000UL
542 && !(sdd->cur_mode & SPI_CPHA))
543 chcfg |= S3C64XX_SPI_CH_HS_EN;
544
545 if (dma_mode) {
546 modecfg |= S3C64XX_SPI_MODE_RXDMA_ON;
547 chcfg |= S3C64XX_SPI_CH_RXCH_ON;
548 writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
549 | S3C64XX_SPI_PACKET_CNT_EN,
550 regs + S3C64XX_SPI_PACKET_CNT);
551 prepare_dma(&sdd->rx_dma, xfer->len, xfer->rx_dma);
552 }
553 }
554
555 writel(modecfg, regs + S3C64XX_SPI_MODE_CFG);
556 writel(chcfg, regs + S3C64XX_SPI_CH_CFG);
557 }
558
559 static inline void enable_cs(struct s3c64xx_spi_driver_data *sdd,
560 struct spi_device *spi)
561 {
562 struct s3c64xx_spi_csinfo *cs;
563
564 if (sdd->tgl_spi != NULL) { /* If last device toggled after mssg */
565 if (sdd->tgl_spi != spi) { /* if last mssg on diff device */
566 /* Deselect the last toggled device */
567 cs = sdd->tgl_spi->controller_data;
568 if (sdd->cs_gpio)
569 gpio_set_value(cs->line,
570 spi->mode & SPI_CS_HIGH ? 0 : 1);
571 }
572 sdd->tgl_spi = NULL;
573 }
574
575 cs = spi->controller_data;
576 if (sdd->cs_gpio)
577 gpio_set_value(cs->line, spi->mode & SPI_CS_HIGH ? 1 : 0);
578
579 /* Start the signals */
580 writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
581 }
582
583 static u32 s3c64xx_spi_wait_for_timeout(struct s3c64xx_spi_driver_data *sdd,
584 int timeout_ms)
585 {
586 void __iomem *regs = sdd->regs;
587 unsigned long val = 1;
588 u32 status;
589
590 /* max fifo depth available */
591 u32 max_fifo = (FIFO_LVL_MASK(sdd) >> 1) + 1;
592
593 if (timeout_ms)
594 val = msecs_to_loops(timeout_ms);
595
596 do {
597 status = readl(regs + S3C64XX_SPI_STATUS);
598 } while (RX_FIFO_LVL(status, sdd) < max_fifo && --val);
599
600 /* return the actual received data length */
601 return RX_FIFO_LVL(status, sdd);
602 }
603
604 static int wait_for_xfer(struct s3c64xx_spi_driver_data *sdd,
605 struct spi_transfer *xfer, int dma_mode)
606 {
607 void __iomem *regs = sdd->regs;
608 unsigned long val;
609 int ms;
610
611 /* millisecs to xfer 'len' bytes @ 'cur_speed' */
612 ms = xfer->len * 8 * 1000 / sdd->cur_speed;
613 ms += 10; /* some tolerance */
614
615 if (dma_mode) {
616 val = msecs_to_jiffies(ms) + 10;
617 val = wait_for_completion_timeout(&sdd->xfer_completion, val);
618 } else {
619 u32 status;
620 val = msecs_to_loops(ms);
621 do {
622 status = readl(regs + S3C64XX_SPI_STATUS);
623 } while (RX_FIFO_LVL(status, sdd) < xfer->len && --val);
624 }
625
626 if (dma_mode) {
627 u32 status;
628
629 /*
630 * If the previous xfer was completed within timeout, then
631 * proceed further else return -EIO.
632 * DmaTx returns after simply writing data in the FIFO,
633 * w/o waiting for real transmission on the bus to finish.
634 * DmaRx returns only after Dma read data from FIFO which
635 * needs bus transmission to finish, so we don't worry if
636 * Xfer involved Rx(with or without Tx).
637 */
638 if (val && !xfer->rx_buf) {
639 val = msecs_to_loops(10);
640 status = readl(regs + S3C64XX_SPI_STATUS);
641 while ((TX_FIFO_LVL(status, sdd)
642 || !S3C64XX_SPI_ST_TX_DONE(status, sdd))
643 && --val) {
644 cpu_relax();
645 status = readl(regs + S3C64XX_SPI_STATUS);
646 }
647
648 }
649
650 /* If timed out while checking rx/tx status return error */
651 if (!val)
652 return -EIO;
653 } else {
654 int loops;
655 u32 cpy_len;
656 u8 *buf;
657
658 /* If it was only Tx */
659 if (!xfer->rx_buf) {
660 sdd->state &= ~TXBUSY;
661 return 0;
662 }
663
664 /*
665 * If the receive length is bigger than the controller fifo
666 * size, calculate the loops and read the fifo as many times.
667 * loops = length / max fifo size (calculated by using the
668 * fifo mask).
669 * For any size less than the fifo size the below code is
670 * executed atleast once.
671 */
672 loops = xfer->len / ((FIFO_LVL_MASK(sdd) >> 1) + 1);
673 buf = xfer->rx_buf;
674 do {
675 /* wait for data to be received in the fifo */
676 cpy_len = s3c64xx_spi_wait_for_timeout(sdd,
677 (loops ? ms : 0));
678
679 switch (sdd->cur_bpw) {
680 case 32:
681 ioread32_rep(regs + S3C64XX_SPI_RX_DATA,
682 buf, cpy_len / 4);
683 break;
684 case 16:
685 ioread16_rep(regs + S3C64XX_SPI_RX_DATA,
686 buf, cpy_len / 2);
687 break;
688 default:
689 ioread8_rep(regs + S3C64XX_SPI_RX_DATA,
690 buf, cpy_len);
691 break;
692 }
693
694 buf = buf + cpy_len;
695 } while (loops--);
696 sdd->state &= ~RXBUSY;
697 }
698
699 return 0;
700 }
701
702 static inline void disable_cs(struct s3c64xx_spi_driver_data *sdd,
703 struct spi_device *spi)
704 {
705 struct s3c64xx_spi_csinfo *cs = spi->controller_data;
706
707 if (sdd->tgl_spi == spi)
708 sdd->tgl_spi = NULL;
709
710 if (sdd->cs_gpio)
711 gpio_set_value(cs->line, spi->mode & SPI_CS_HIGH ? 0 : 1);
712
713 /* Quiese the signals */
714 writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
715 }
716
717 static void s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
718 {
719 void __iomem *regs = sdd->regs;
720 u32 val;
721
722 /* Disable Clock */
723 if (sdd->port_conf->clk_from_cmu) {
724 clk_disable_unprepare(sdd->src_clk);
725 } else {
726 val = readl(regs + S3C64XX_SPI_CLK_CFG);
727 val &= ~S3C64XX_SPI_ENCLK_ENABLE;
728 writel(val, regs + S3C64XX_SPI_CLK_CFG);
729 }
730
731 /* Set Polarity and Phase */
732 val = readl(regs + S3C64XX_SPI_CH_CFG);
733 val &= ~(S3C64XX_SPI_CH_SLAVE |
734 S3C64XX_SPI_CPOL_L |
735 S3C64XX_SPI_CPHA_B);
736
737 if (sdd->cur_mode & SPI_CPOL)
738 val |= S3C64XX_SPI_CPOL_L;
739
740 if (sdd->cur_mode & SPI_CPHA)
741 val |= S3C64XX_SPI_CPHA_B;
742
743 writel(val, regs + S3C64XX_SPI_CH_CFG);
744
745 /* Set Channel & DMA Mode */
746 val = readl(regs + S3C64XX_SPI_MODE_CFG);
747 val &= ~(S3C64XX_SPI_MODE_BUS_TSZ_MASK
748 | S3C64XX_SPI_MODE_CH_TSZ_MASK);
749
750 switch (sdd->cur_bpw) {
751 case 32:
752 val |= S3C64XX_SPI_MODE_BUS_TSZ_WORD;
753 val |= S3C64XX_SPI_MODE_CH_TSZ_WORD;
754 break;
755 case 16:
756 val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD;
757 val |= S3C64XX_SPI_MODE_CH_TSZ_HALFWORD;
758 break;
759 default:
760 val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE;
761 val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE;
762 break;
763 }
764
765 writel(val, regs + S3C64XX_SPI_MODE_CFG);
766
767 if (sdd->port_conf->clk_from_cmu) {
768 /* Configure Clock */
769 /* There is half-multiplier before the SPI */
770 clk_set_rate(sdd->src_clk, sdd->cur_speed * 2);
771 /* Enable Clock */
772 clk_prepare_enable(sdd->src_clk);
773 } else {
774 /* Configure Clock */
775 val = readl(regs + S3C64XX_SPI_CLK_CFG);
776 val &= ~S3C64XX_SPI_PSR_MASK;
777 val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / 2 - 1)
778 & S3C64XX_SPI_PSR_MASK);
779 writel(val, regs + S3C64XX_SPI_CLK_CFG);
780
781 /* Enable Clock */
782 val = readl(regs + S3C64XX_SPI_CLK_CFG);
783 val |= S3C64XX_SPI_ENCLK_ENABLE;
784 writel(val, regs + S3C64XX_SPI_CLK_CFG);
785 }
786 }
787
788 #define XFER_DMAADDR_INVALID DMA_BIT_MASK(32)
789
790 static int s3c64xx_spi_map_mssg(struct s3c64xx_spi_driver_data *sdd,
791 struct spi_message *msg)
792 {
793 struct device *dev = &sdd->pdev->dev;
794 struct spi_transfer *xfer;
795
796 if (is_polling(sdd) || msg->is_dma_mapped)
797 return 0;
798
799 /* First mark all xfer unmapped */
800 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
801 xfer->rx_dma = XFER_DMAADDR_INVALID;
802 xfer->tx_dma = XFER_DMAADDR_INVALID;
803 }
804
805 /* Map until end or first fail */
806 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
807
808 if (xfer->len <= ((FIFO_LVL_MASK(sdd) >> 1) + 1))
809 continue;
810
811 if (xfer->tx_buf != NULL) {
812 xfer->tx_dma = dma_map_single(dev,
813 (void *)xfer->tx_buf, xfer->len,
814 DMA_TO_DEVICE);
815 if (dma_mapping_error(dev, xfer->tx_dma)) {
816 dev_err(dev, "dma_map_single Tx failed\n");
817 xfer->tx_dma = XFER_DMAADDR_INVALID;
818 return -ENOMEM;
819 }
820 }
821
822 if (xfer->rx_buf != NULL) {
823 xfer->rx_dma = dma_map_single(dev, xfer->rx_buf,
824 xfer->len, DMA_FROM_DEVICE);
825 if (dma_mapping_error(dev, xfer->rx_dma)) {
826 dev_err(dev, "dma_map_single Rx failed\n");
827 dma_unmap_single(dev, xfer->tx_dma,
828 xfer->len, DMA_TO_DEVICE);
829 xfer->tx_dma = XFER_DMAADDR_INVALID;
830 xfer->rx_dma = XFER_DMAADDR_INVALID;
831 return -ENOMEM;
832 }
833 }
834 }
835
836 return 0;
837 }
838
839 static void s3c64xx_spi_unmap_mssg(struct s3c64xx_spi_driver_data *sdd,
840 struct spi_message *msg)
841 {
842 struct device *dev = &sdd->pdev->dev;
843 struct spi_transfer *xfer;
844
845 if (is_polling(sdd) || msg->is_dma_mapped)
846 return;
847
848 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
849
850 if (xfer->len <= ((FIFO_LVL_MASK(sdd) >> 1) + 1))
851 continue;
852
853 if (xfer->rx_buf != NULL
854 && xfer->rx_dma != XFER_DMAADDR_INVALID)
855 dma_unmap_single(dev, xfer->rx_dma,
856 xfer->len, DMA_FROM_DEVICE);
857
858 if (xfer->tx_buf != NULL
859 && xfer->tx_dma != XFER_DMAADDR_INVALID)
860 dma_unmap_single(dev, xfer->tx_dma,
861 xfer->len, DMA_TO_DEVICE);
862 }
863 }
864
865 static int s3c64xx_spi_transfer_one_message(struct spi_master *master,
866 struct spi_message *msg)
867 {
868 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
869 struct spi_device *spi = msg->spi;
870 struct s3c64xx_spi_csinfo *cs = spi->controller_data;
871 struct spi_transfer *xfer;
872 int status = 0, cs_toggle = 0;
873 u32 speed;
874 u8 bpw;
875
876 /* If Master's(controller) state differs from that needed by Slave */
877 if (sdd->cur_speed != spi->max_speed_hz
878 || sdd->cur_mode != spi->mode
879 || sdd->cur_bpw != spi->bits_per_word) {
880 sdd->cur_bpw = spi->bits_per_word;
881 sdd->cur_speed = spi->max_speed_hz;
882 sdd->cur_mode = spi->mode;
883 s3c64xx_spi_config(sdd);
884 }
885
886 /* Map all the transfers if needed */
887 if (s3c64xx_spi_map_mssg(sdd, msg)) {
888 dev_err(&spi->dev,
889 "Xfer: Unable to map message buffers!\n");
890 status = -ENOMEM;
891 goto out;
892 }
893
894 /* Configure feedback delay */
895 writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK);
896
897 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
898
899 unsigned long flags;
900 int use_dma;
901
902 INIT_COMPLETION(sdd->xfer_completion);
903
904 /* Only BPW and Speed may change across transfers */
905 bpw = xfer->bits_per_word;
906 speed = xfer->speed_hz ? : spi->max_speed_hz;
907
908 if (xfer->len % (bpw / 8)) {
909 dev_err(&spi->dev,
910 "Xfer length(%u) not a multiple of word size(%u)\n",
911 xfer->len, bpw / 8);
912 status = -EIO;
913 goto out;
914 }
915
916 if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) {
917 sdd->cur_bpw = bpw;
918 sdd->cur_speed = speed;
919 s3c64xx_spi_config(sdd);
920 }
921
922 /* Polling method for xfers not bigger than FIFO capacity */
923 use_dma = 0;
924 if (!is_polling(sdd) &&
925 (sdd->rx_dma.ch && sdd->tx_dma.ch &&
926 (xfer->len > ((FIFO_LVL_MASK(sdd) >> 1) + 1))))
927 use_dma = 1;
928
929 spin_lock_irqsave(&sdd->lock, flags);
930
931 /* Pending only which is to be done */
932 sdd->state &= ~RXBUSY;
933 sdd->state &= ~TXBUSY;
934
935 enable_datapath(sdd, spi, xfer, use_dma);
936
937 /* Slave Select */
938 enable_cs(sdd, spi);
939
940 spin_unlock_irqrestore(&sdd->lock, flags);
941
942 status = wait_for_xfer(sdd, xfer, use_dma);
943
944 if (status) {
945 dev_err(&spi->dev, "I/O Error: rx-%d tx-%d res:rx-%c tx-%c len-%d\n",
946 xfer->rx_buf ? 1 : 0, xfer->tx_buf ? 1 : 0,
947 (sdd->state & RXBUSY) ? 'f' : 'p',
948 (sdd->state & TXBUSY) ? 'f' : 'p',
949 xfer->len);
950
951 if (use_dma) {
952 if (xfer->tx_buf != NULL
953 && (sdd->state & TXBUSY))
954 s3c64xx_spi_dma_stop(sdd, &sdd->tx_dma);
955 if (xfer->rx_buf != NULL
956 && (sdd->state & RXBUSY))
957 s3c64xx_spi_dma_stop(sdd, &sdd->rx_dma);
958 }
959
960 goto out;
961 }
962
963 if (xfer->delay_usecs)
964 udelay(xfer->delay_usecs);
965
966 if (xfer->cs_change) {
967 /* Hint that the next mssg is gonna be
968 for the same device */
969 if (list_is_last(&xfer->transfer_list,
970 &msg->transfers))
971 cs_toggle = 1;
972 }
973
974 msg->actual_length += xfer->len;
975
976 flush_fifo(sdd);
977 }
978
979 out:
980 if (!cs_toggle || status)
981 disable_cs(sdd, spi);
982 else
983 sdd->tgl_spi = spi;
984
985 s3c64xx_spi_unmap_mssg(sdd, msg);
986
987 msg->status = status;
988
989 spi_finalize_current_message(master);
990
991 return 0;
992 }
993
994 static struct s3c64xx_spi_csinfo *s3c64xx_get_slave_ctrldata(
995 struct spi_device *spi)
996 {
997 struct s3c64xx_spi_csinfo *cs;
998 struct device_node *slave_np, *data_np = NULL;
999 struct s3c64xx_spi_driver_data *sdd;
1000 u32 fb_delay = 0;
1001
1002 sdd = spi_master_get_devdata(spi->master);
1003 slave_np = spi->dev.of_node;
1004 if (!slave_np) {
1005 dev_err(&spi->dev, "device node not found\n");
1006 return ERR_PTR(-EINVAL);
1007 }
1008
1009 data_np = of_get_child_by_name(slave_np, "controller-data");
1010 if (!data_np) {
1011 dev_err(&spi->dev, "child node 'controller-data' not found\n");
1012 return ERR_PTR(-EINVAL);
1013 }
1014
1015 cs = kzalloc(sizeof(*cs), GFP_KERNEL);
1016 if (!cs) {
1017 dev_err(&spi->dev, "could not allocate memory for controller data\n");
1018 of_node_put(data_np);
1019 return ERR_PTR(-ENOMEM);
1020 }
1021
1022 /* The CS line is asserted/deasserted by the gpio pin */
1023 if (sdd->cs_gpio)
1024 cs->line = of_get_named_gpio(data_np, "cs-gpio", 0);
1025
1026 if (!gpio_is_valid(cs->line)) {
1027 dev_err(&spi->dev, "chip select gpio is not specified or invalid\n");
1028 kfree(cs);
1029 of_node_put(data_np);
1030 return ERR_PTR(-EINVAL);
1031 }
1032
1033 of_property_read_u32(data_np, "samsung,spi-feedback-delay", &fb_delay);
1034 cs->fb_delay = fb_delay;
1035 of_node_put(data_np);
1036 return cs;
1037 }
1038
1039 /*
1040 * Here we only check the validity of requested configuration
1041 * and save the configuration in a local data-structure.
1042 * The controller is actually configured only just before we
1043 * get a message to transfer.
1044 */
1045 static int s3c64xx_spi_setup(struct spi_device *spi)
1046 {
1047 struct s3c64xx_spi_csinfo *cs = spi->controller_data;
1048 struct s3c64xx_spi_driver_data *sdd;
1049 struct s3c64xx_spi_info *sci;
1050 int err;
1051
1052 sdd = spi_master_get_devdata(spi->master);
1053 if (!cs && spi->dev.of_node) {
1054 cs = s3c64xx_get_slave_ctrldata(spi);
1055 spi->controller_data = cs;
1056 }
1057
1058 if (IS_ERR_OR_NULL(cs)) {
1059 dev_err(&spi->dev, "No CS for SPI(%d)\n", spi->chip_select);
1060 return -ENODEV;
1061 }
1062
1063 if (!spi_get_ctldata(spi)) {
1064 /* Request gpio only if cs line is asserted by gpio pins */
1065 if (sdd->cs_gpio) {
1066 err = gpio_request_one(cs->line, GPIOF_OUT_INIT_HIGH,
1067 dev_name(&spi->dev));
1068 if (err) {
1069 dev_err(&spi->dev,
1070 "Failed to get /CS gpio [%d]: %d\n",
1071 cs->line, err);
1072 goto err_gpio_req;
1073 }
1074 }
1075
1076 spi_set_ctldata(spi, cs);
1077 }
1078
1079 sci = sdd->cntrlr_info;
1080
1081 pm_runtime_get_sync(&sdd->pdev->dev);
1082
1083 /* Check if we can provide the requested rate */
1084 if (!sdd->port_conf->clk_from_cmu) {
1085 u32 psr, speed;
1086
1087 /* Max possible */
1088 speed = clk_get_rate(sdd->src_clk) / 2 / (0 + 1);
1089
1090 if (spi->max_speed_hz > speed)
1091 spi->max_speed_hz = speed;
1092
1093 psr = clk_get_rate(sdd->src_clk) / 2 / spi->max_speed_hz - 1;
1094 psr &= S3C64XX_SPI_PSR_MASK;
1095 if (psr == S3C64XX_SPI_PSR_MASK)
1096 psr--;
1097
1098 speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
1099 if (spi->max_speed_hz < speed) {
1100 if (psr+1 < S3C64XX_SPI_PSR_MASK) {
1101 psr++;
1102 } else {
1103 err = -EINVAL;
1104 goto setup_exit;
1105 }
1106 }
1107
1108 speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
1109 if (spi->max_speed_hz >= speed) {
1110 spi->max_speed_hz = speed;
1111 } else {
1112 dev_err(&spi->dev, "Can't set %dHz transfer speed\n",
1113 spi->max_speed_hz);
1114 err = -EINVAL;
1115 goto setup_exit;
1116 }
1117 }
1118
1119 pm_runtime_put(&sdd->pdev->dev);
1120 disable_cs(sdd, spi);
1121 return 0;
1122
1123 setup_exit:
1124 /* setup() returns with device de-selected */
1125 disable_cs(sdd, spi);
1126
1127 gpio_free(cs->line);
1128 spi_set_ctldata(spi, NULL);
1129
1130 err_gpio_req:
1131 if (spi->dev.of_node)
1132 kfree(cs);
1133
1134 return err;
1135 }
1136
1137 static void s3c64xx_spi_cleanup(struct spi_device *spi)
1138 {
1139 struct s3c64xx_spi_csinfo *cs = spi_get_ctldata(spi);
1140 struct s3c64xx_spi_driver_data *sdd;
1141
1142 sdd = spi_master_get_devdata(spi->master);
1143 if (cs && sdd->cs_gpio) {
1144 gpio_free(cs->line);
1145 if (spi->dev.of_node)
1146 kfree(cs);
1147 }
1148 spi_set_ctldata(spi, NULL);
1149 }
1150
1151 static irqreturn_t s3c64xx_spi_irq(int irq, void *data)
1152 {
1153 struct s3c64xx_spi_driver_data *sdd = data;
1154 struct spi_master *spi = sdd->master;
1155 unsigned int val, clr = 0;
1156
1157 val = readl(sdd->regs + S3C64XX_SPI_STATUS);
1158
1159 if (val & S3C64XX_SPI_ST_RX_OVERRUN_ERR) {
1160 clr = S3C64XX_SPI_PND_RX_OVERRUN_CLR;
1161 dev_err(&spi->dev, "RX overrun\n");
1162 }
1163 if (val & S3C64XX_SPI_ST_RX_UNDERRUN_ERR) {
1164 clr |= S3C64XX_SPI_PND_RX_UNDERRUN_CLR;
1165 dev_err(&spi->dev, "RX underrun\n");
1166 }
1167 if (val & S3C64XX_SPI_ST_TX_OVERRUN_ERR) {
1168 clr |= S3C64XX_SPI_PND_TX_OVERRUN_CLR;
1169 dev_err(&spi->dev, "TX overrun\n");
1170 }
1171 if (val & S3C64XX_SPI_ST_TX_UNDERRUN_ERR) {
1172 clr |= S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
1173 dev_err(&spi->dev, "TX underrun\n");
1174 }
1175
1176 /* Clear the pending irq by setting and then clearing it */
1177 writel(clr, sdd->regs + S3C64XX_SPI_PENDING_CLR);
1178 writel(0, sdd->regs + S3C64XX_SPI_PENDING_CLR);
1179
1180 return IRQ_HANDLED;
1181 }
1182
1183 static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd, int channel)
1184 {
1185 struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1186 void __iomem *regs = sdd->regs;
1187 unsigned int val;
1188
1189 sdd->cur_speed = 0;
1190
1191 writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
1192
1193 /* Disable Interrupts - we use Polling if not DMA mode */
1194 writel(0, regs + S3C64XX_SPI_INT_EN);
1195
1196 if (!sdd->port_conf->clk_from_cmu)
1197 writel(sci->src_clk_nr << S3C64XX_SPI_CLKSEL_SRCSHFT,
1198 regs + S3C64XX_SPI_CLK_CFG);
1199 writel(0, regs + S3C64XX_SPI_MODE_CFG);
1200 writel(0, regs + S3C64XX_SPI_PACKET_CNT);
1201
1202 /* Clear any irq pending bits, should set and clear the bits */
1203 val = S3C64XX_SPI_PND_RX_OVERRUN_CLR |
1204 S3C64XX_SPI_PND_RX_UNDERRUN_CLR |
1205 S3C64XX_SPI_PND_TX_OVERRUN_CLR |
1206 S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
1207 writel(val, regs + S3C64XX_SPI_PENDING_CLR);
1208 writel(0, regs + S3C64XX_SPI_PENDING_CLR);
1209
1210 writel(0, regs + S3C64XX_SPI_SWAP_CFG);
1211
1212 val = readl(regs + S3C64XX_SPI_MODE_CFG);
1213 val &= ~S3C64XX_SPI_MODE_4BURST;
1214 val &= ~(S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
1215 val |= (S3C64XX_SPI_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
1216 writel(val, regs + S3C64XX_SPI_MODE_CFG);
1217
1218 flush_fifo(sdd);
1219 }
1220
1221 #ifdef CONFIG_OF
1222 static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
1223 {
1224 struct s3c64xx_spi_info *sci;
1225 u32 temp;
1226
1227 sci = devm_kzalloc(dev, sizeof(*sci), GFP_KERNEL);
1228 if (!sci) {
1229 dev_err(dev, "memory allocation for spi_info failed\n");
1230 return ERR_PTR(-ENOMEM);
1231 }
1232
1233 if (of_property_read_u32(dev->of_node, "samsung,spi-src-clk", &temp)) {
1234 dev_warn(dev, "spi bus clock parent not specified, using clock at index 0 as parent\n");
1235 sci->src_clk_nr = 0;
1236 } else {
1237 sci->src_clk_nr = temp;
1238 }
1239
1240 if (of_property_read_u32(dev->of_node, "num-cs", &temp)) {
1241 dev_warn(dev, "number of chip select lines not specified, assuming 1 chip select line\n");
1242 sci->num_cs = 1;
1243 } else {
1244 sci->num_cs = temp;
1245 }
1246
1247 return sci;
1248 }
1249 #else
1250 static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
1251 {
1252 return dev_get_platdata(dev);
1253 }
1254 #endif
1255
1256 static const struct of_device_id s3c64xx_spi_dt_match[];
1257
1258 static inline struct s3c64xx_spi_port_config *s3c64xx_spi_get_port_config(
1259 struct platform_device *pdev)
1260 {
1261 #ifdef CONFIG_OF
1262 if (pdev->dev.of_node) {
1263 const struct of_device_id *match;
1264 match = of_match_node(s3c64xx_spi_dt_match, pdev->dev.of_node);
1265 return (struct s3c64xx_spi_port_config *)match->data;
1266 }
1267 #endif
1268 return (struct s3c64xx_spi_port_config *)
1269 platform_get_device_id(pdev)->driver_data;
1270 }
1271
1272 static int s3c64xx_spi_probe(struct platform_device *pdev)
1273 {
1274 struct resource *mem_res;
1275 struct resource *res;
1276 struct s3c64xx_spi_driver_data *sdd;
1277 struct s3c64xx_spi_info *sci = dev_get_platdata(&pdev->dev);
1278 struct spi_master *master;
1279 int ret, irq;
1280 char clk_name[16];
1281
1282 if (!sci && pdev->dev.of_node) {
1283 sci = s3c64xx_spi_parse_dt(&pdev->dev);
1284 if (IS_ERR(sci))
1285 return PTR_ERR(sci);
1286 }
1287
1288 if (!sci) {
1289 dev_err(&pdev->dev, "platform_data missing!\n");
1290 return -ENODEV;
1291 }
1292
1293 mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1294 if (mem_res == NULL) {
1295 dev_err(&pdev->dev, "Unable to get SPI MEM resource\n");
1296 return -ENXIO;
1297 }
1298
1299 irq = platform_get_irq(pdev, 0);
1300 if (irq < 0) {
1301 dev_warn(&pdev->dev, "Failed to get IRQ: %d\n", irq);
1302 return irq;
1303 }
1304
1305 master = spi_alloc_master(&pdev->dev,
1306 sizeof(struct s3c64xx_spi_driver_data));
1307 if (master == NULL) {
1308 dev_err(&pdev->dev, "Unable to allocate SPI Master\n");
1309 return -ENOMEM;
1310 }
1311
1312 platform_set_drvdata(pdev, master);
1313
1314 sdd = spi_master_get_devdata(master);
1315 sdd->port_conf = s3c64xx_spi_get_port_config(pdev);
1316 sdd->master = master;
1317 sdd->cntrlr_info = sci;
1318 sdd->pdev = pdev;
1319 sdd->sfr_start = mem_res->start;
1320 sdd->cs_gpio = true;
1321 if (pdev->dev.of_node) {
1322 if (!of_find_property(pdev->dev.of_node, "cs-gpio", NULL))
1323 sdd->cs_gpio = false;
1324
1325 ret = of_alias_get_id(pdev->dev.of_node, "spi");
1326 if (ret < 0) {
1327 dev_err(&pdev->dev, "failed to get alias id, errno %d\n",
1328 ret);
1329 goto err0;
1330 }
1331 sdd->port_id = ret;
1332 } else {
1333 sdd->port_id = pdev->id;
1334 }
1335
1336 sdd->cur_bpw = 8;
1337
1338 if (!sdd->pdev->dev.of_node) {
1339 res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
1340 if (!res) {
1341 dev_warn(&pdev->dev, "Unable to get SPI tx dma resource. Switching to poll mode\n");
1342 sdd->port_conf->quirks = S3C64XX_SPI_QUIRK_POLL;
1343 } else
1344 sdd->tx_dma.dmach = res->start;
1345
1346 res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
1347 if (!res) {
1348 dev_warn(&pdev->dev, "Unable to get SPI rx dma resource. Switching to poll mode\n");
1349 sdd->port_conf->quirks = S3C64XX_SPI_QUIRK_POLL;
1350 } else
1351 sdd->rx_dma.dmach = res->start;
1352 }
1353
1354 sdd->tx_dma.direction = DMA_MEM_TO_DEV;
1355 sdd->rx_dma.direction = DMA_DEV_TO_MEM;
1356
1357 master->dev.of_node = pdev->dev.of_node;
1358 master->bus_num = sdd->port_id;
1359 master->setup = s3c64xx_spi_setup;
1360 master->cleanup = s3c64xx_spi_cleanup;
1361 master->prepare_transfer_hardware = s3c64xx_spi_prepare_transfer;
1362 master->transfer_one_message = s3c64xx_spi_transfer_one_message;
1363 master->unprepare_transfer_hardware = s3c64xx_spi_unprepare_transfer;
1364 master->num_chipselect = sci->num_cs;
1365 master->dma_alignment = 8;
1366 master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) |
1367 SPI_BPW_MASK(8);
1368 /* the spi->mode bits understood by this driver: */
1369 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1370 master->auto_runtime_pm = true;
1371
1372 sdd->regs = devm_ioremap_resource(&pdev->dev, mem_res);
1373 if (IS_ERR(sdd->regs)) {
1374 ret = PTR_ERR(sdd->regs);
1375 goto err0;
1376 }
1377
1378 if (sci->cfg_gpio && sci->cfg_gpio()) {
1379 dev_err(&pdev->dev, "Unable to config gpio\n");
1380 ret = -EBUSY;
1381 goto err0;
1382 }
1383
1384 /* Setup clocks */
1385 sdd->clk = devm_clk_get(&pdev->dev, "spi");
1386 if (IS_ERR(sdd->clk)) {
1387 dev_err(&pdev->dev, "Unable to acquire clock 'spi'\n");
1388 ret = PTR_ERR(sdd->clk);
1389 goto err0;
1390 }
1391
1392 if (clk_prepare_enable(sdd->clk)) {
1393 dev_err(&pdev->dev, "Couldn't enable clock 'spi'\n");
1394 ret = -EBUSY;
1395 goto err0;
1396 }
1397
1398 sprintf(clk_name, "spi_busclk%d", sci->src_clk_nr);
1399 sdd->src_clk = devm_clk_get(&pdev->dev, clk_name);
1400 if (IS_ERR(sdd->src_clk)) {
1401 dev_err(&pdev->dev,
1402 "Unable to acquire clock '%s'\n", clk_name);
1403 ret = PTR_ERR(sdd->src_clk);
1404 goto err2;
1405 }
1406
1407 if (clk_prepare_enable(sdd->src_clk)) {
1408 dev_err(&pdev->dev, "Couldn't enable clock '%s'\n", clk_name);
1409 ret = -EBUSY;
1410 goto err2;
1411 }
1412
1413 /* Setup Deufult Mode */
1414 s3c64xx_spi_hwinit(sdd, sdd->port_id);
1415
1416 spin_lock_init(&sdd->lock);
1417 init_completion(&sdd->xfer_completion);
1418
1419 ret = devm_request_irq(&pdev->dev, irq, s3c64xx_spi_irq, 0,
1420 "spi-s3c64xx", sdd);
1421 if (ret != 0) {
1422 dev_err(&pdev->dev, "Failed to request IRQ %d: %d\n",
1423 irq, ret);
1424 goto err3;
1425 }
1426
1427 writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
1428 S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
1429 sdd->regs + S3C64XX_SPI_INT_EN);
1430
1431 pm_runtime_enable(&pdev->dev);
1432
1433 if (spi_register_master(master)) {
1434 dev_err(&pdev->dev, "cannot register SPI master\n");
1435 ret = -EBUSY;
1436 goto err3;
1437 }
1438
1439 dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d with %d Slaves attached\n",
1440 sdd->port_id, master->num_chipselect);
1441 dev_dbg(&pdev->dev, "\tIOmem=[%pR]\tDMA=[Rx-%d, Tx-%d]\n",
1442 mem_res,
1443 sdd->rx_dma.dmach, sdd->tx_dma.dmach);
1444
1445 return 0;
1446
1447 err3:
1448 clk_disable_unprepare(sdd->src_clk);
1449 err2:
1450 clk_disable_unprepare(sdd->clk);
1451 err0:
1452 spi_master_put(master);
1453
1454 return ret;
1455 }
1456
1457 static int s3c64xx_spi_remove(struct platform_device *pdev)
1458 {
1459 struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
1460 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1461
1462 pm_runtime_disable(&pdev->dev);
1463
1464 spi_unregister_master(master);
1465
1466 writel(0, sdd->regs + S3C64XX_SPI_INT_EN);
1467
1468 clk_disable_unprepare(sdd->src_clk);
1469
1470 clk_disable_unprepare(sdd->clk);
1471
1472 spi_master_put(master);
1473
1474 return 0;
1475 }
1476
1477 #ifdef CONFIG_PM_SLEEP
1478 static int s3c64xx_spi_suspend(struct device *dev)
1479 {
1480 struct spi_master *master = dev_get_drvdata(dev);
1481 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1482
1483 spi_master_suspend(master);
1484
1485 /* Disable the clock */
1486 clk_disable_unprepare(sdd->src_clk);
1487 clk_disable_unprepare(sdd->clk);
1488
1489 sdd->cur_speed = 0; /* Output Clock is stopped */
1490
1491 return 0;
1492 }
1493
1494 static int s3c64xx_spi_resume(struct device *dev)
1495 {
1496 struct spi_master *master = dev_get_drvdata(dev);
1497 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1498 struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1499
1500 if (sci->cfg_gpio)
1501 sci->cfg_gpio();
1502
1503 /* Enable the clock */
1504 clk_prepare_enable(sdd->src_clk);
1505 clk_prepare_enable(sdd->clk);
1506
1507 s3c64xx_spi_hwinit(sdd, sdd->port_id);
1508
1509 spi_master_resume(master);
1510
1511 return 0;
1512 }
1513 #endif /* CONFIG_PM_SLEEP */
1514
1515 #ifdef CONFIG_PM_RUNTIME
1516 static int s3c64xx_spi_runtime_suspend(struct device *dev)
1517 {
1518 struct spi_master *master = dev_get_drvdata(dev);
1519 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1520
1521 clk_disable_unprepare(sdd->clk);
1522 clk_disable_unprepare(sdd->src_clk);
1523
1524 return 0;
1525 }
1526
1527 static int s3c64xx_spi_runtime_resume(struct device *dev)
1528 {
1529 struct spi_master *master = dev_get_drvdata(dev);
1530 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1531
1532 clk_prepare_enable(sdd->src_clk);
1533 clk_prepare_enable(sdd->clk);
1534
1535 return 0;
1536 }
1537 #endif /* CONFIG_PM_RUNTIME */
1538
1539 static const struct dev_pm_ops s3c64xx_spi_pm = {
1540 SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume)
1541 SET_RUNTIME_PM_OPS(s3c64xx_spi_runtime_suspend,
1542 s3c64xx_spi_runtime_resume, NULL)
1543 };
1544
1545 static struct s3c64xx_spi_port_config s3c2443_spi_port_config = {
1546 .fifo_lvl_mask = { 0x7f },
1547 .rx_lvl_offset = 13,
1548 .tx_st_done = 21,
1549 .high_speed = true,
1550 };
1551
1552 static struct s3c64xx_spi_port_config s3c6410_spi_port_config = {
1553 .fifo_lvl_mask = { 0x7f, 0x7F },
1554 .rx_lvl_offset = 13,
1555 .tx_st_done = 21,
1556 };
1557
1558 static struct s3c64xx_spi_port_config s5p64x0_spi_port_config = {
1559 .fifo_lvl_mask = { 0x1ff, 0x7F },
1560 .rx_lvl_offset = 15,
1561 .tx_st_done = 25,
1562 };
1563
1564 static struct s3c64xx_spi_port_config s5pc100_spi_port_config = {
1565 .fifo_lvl_mask = { 0x7f, 0x7F },
1566 .rx_lvl_offset = 13,
1567 .tx_st_done = 21,
1568 .high_speed = true,
1569 };
1570
1571 static struct s3c64xx_spi_port_config s5pv210_spi_port_config = {
1572 .fifo_lvl_mask = { 0x1ff, 0x7F },
1573 .rx_lvl_offset = 15,
1574 .tx_st_done = 25,
1575 .high_speed = true,
1576 };
1577
1578 static struct s3c64xx_spi_port_config exynos4_spi_port_config = {
1579 .fifo_lvl_mask = { 0x1ff, 0x7F, 0x7F },
1580 .rx_lvl_offset = 15,
1581 .tx_st_done = 25,
1582 .high_speed = true,
1583 .clk_from_cmu = true,
1584 };
1585
1586 static struct s3c64xx_spi_port_config exynos5440_spi_port_config = {
1587 .fifo_lvl_mask = { 0x1ff },
1588 .rx_lvl_offset = 15,
1589 .tx_st_done = 25,
1590 .high_speed = true,
1591 .clk_from_cmu = true,
1592 .quirks = S3C64XX_SPI_QUIRK_POLL,
1593 };
1594
1595 static struct platform_device_id s3c64xx_spi_driver_ids[] = {
1596 {
1597 .name = "s3c2443-spi",
1598 .driver_data = (kernel_ulong_t)&s3c2443_spi_port_config,
1599 }, {
1600 .name = "s3c6410-spi",
1601 .driver_data = (kernel_ulong_t)&s3c6410_spi_port_config,
1602 }, {
1603 .name = "s5p64x0-spi",
1604 .driver_data = (kernel_ulong_t)&s5p64x0_spi_port_config,
1605 }, {
1606 .name = "s5pc100-spi",
1607 .driver_data = (kernel_ulong_t)&s5pc100_spi_port_config,
1608 }, {
1609 .name = "s5pv210-spi",
1610 .driver_data = (kernel_ulong_t)&s5pv210_spi_port_config,
1611 }, {
1612 .name = "exynos4210-spi",
1613 .driver_data = (kernel_ulong_t)&exynos4_spi_port_config,
1614 },
1615 { },
1616 };
1617
1618 static const struct of_device_id s3c64xx_spi_dt_match[] = {
1619 { .compatible = "samsung,exynos4210-spi",
1620 .data = (void *)&exynos4_spi_port_config,
1621 },
1622 { .compatible = "samsung,exynos5440-spi",
1623 .data = (void *)&exynos5440_spi_port_config,
1624 },
1625 { },
1626 };
1627 MODULE_DEVICE_TABLE(of, s3c64xx_spi_dt_match);
1628
1629 static struct platform_driver s3c64xx_spi_driver = {
1630 .driver = {
1631 .name = "s3c64xx-spi",
1632 .owner = THIS_MODULE,
1633 .pm = &s3c64xx_spi_pm,
1634 .of_match_table = of_match_ptr(s3c64xx_spi_dt_match),
1635 },
1636 .remove = s3c64xx_spi_remove,
1637 .id_table = s3c64xx_spi_driver_ids,
1638 };
1639 MODULE_ALIAS("platform:s3c64xx-spi");
1640
1641 static int __init s3c64xx_spi_init(void)
1642 {
1643 return platform_driver_probe(&s3c64xx_spi_driver, s3c64xx_spi_probe);
1644 }
1645 subsys_initcall(s3c64xx_spi_init);
1646
1647 static void __exit s3c64xx_spi_exit(void)
1648 {
1649 platform_driver_unregister(&s3c64xx_spi_driver);
1650 }
1651 module_exit(s3c64xx_spi_exit);
1652
1653 MODULE_AUTHOR("Jaswinder Singh <jassi.brar@samsung.com>");
1654 MODULE_DESCRIPTION("S3C64XX SPI Controller Driver");
1655 MODULE_LICENSE("GPL");
Linux with added FPC-III support