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PM / sleep: Asynchronous threads for suspend_noirq
[linux/fpc-iii.git] / drivers / spi / spi-s3c64xx.c
blobae907dde1371c9133c526ad66daf16155d03fbe9
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 bool cs_gpio;
209 };
210
211 static void flush_fifo(struct s3c64xx_spi_driver_data *sdd)
212 {
213 void __iomem *regs = sdd->regs;
214 unsigned long loops;
215 u32 val;
216
217 writel(0, regs + S3C64XX_SPI_PACKET_CNT);
218
219 val = readl(regs + S3C64XX_SPI_CH_CFG);
220 val &= ~(S3C64XX_SPI_CH_RXCH_ON | S3C64XX_SPI_CH_TXCH_ON);
221 writel(val, regs + S3C64XX_SPI_CH_CFG);
222
223 val = readl(regs + S3C64XX_SPI_CH_CFG);
224 val |= S3C64XX_SPI_CH_SW_RST;
225 val &= ~S3C64XX_SPI_CH_HS_EN;
226 writel(val, regs + S3C64XX_SPI_CH_CFG);
227
228 /* Flush TxFIFO*/
229 loops = msecs_to_loops(1);
230 do {
231 val = readl(regs + S3C64XX_SPI_STATUS);
232 } while (TX_FIFO_LVL(val, sdd) && loops--);
233
234 if (loops == 0)
235 dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n");
236
237 /* Flush RxFIFO*/
238 loops = msecs_to_loops(1);
239 do {
240 val = readl(regs + S3C64XX_SPI_STATUS);
241 if (RX_FIFO_LVL(val, sdd))
242 readl(regs + S3C64XX_SPI_RX_DATA);
243 else
244 break;
245 } while (loops--);
246
247 if (loops == 0)
248 dev_warn(&sdd->pdev->dev, "Timed out flushing RX FIFO\n");
249
250 val = readl(regs + S3C64XX_SPI_CH_CFG);
251 val &= ~S3C64XX_SPI_CH_SW_RST;
252 writel(val, regs + S3C64XX_SPI_CH_CFG);
253
254 val = readl(regs + S3C64XX_SPI_MODE_CFG);
255 val &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
256 writel(val, regs + S3C64XX_SPI_MODE_CFG);
257 }
258
259 static void s3c64xx_spi_dmacb(void *data)
260 {
261 struct s3c64xx_spi_driver_data *sdd;
262 struct s3c64xx_spi_dma_data *dma = data;
263 unsigned long flags;
264
265 if (dma->direction == DMA_DEV_TO_MEM)
266 sdd = container_of(data,
267 struct s3c64xx_spi_driver_data, rx_dma);
268 else
269 sdd = container_of(data,
270 struct s3c64xx_spi_driver_data, tx_dma);
271
272 spin_lock_irqsave(&sdd->lock, flags);
273
274 if (dma->direction == DMA_DEV_TO_MEM) {
275 sdd->state &= ~RXBUSY;
276 if (!(sdd->state & TXBUSY))
277 complete(&sdd->xfer_completion);
278 } else {
279 sdd->state &= ~TXBUSY;
280 if (!(sdd->state & RXBUSY))
281 complete(&sdd->xfer_completion);
282 }
283
284 spin_unlock_irqrestore(&sdd->lock, flags);
285 }
286
287 #ifdef CONFIG_S3C_DMA
288 /* FIXME: remove this section once arch/arm/mach-s3c64xx uses dmaengine */
289
290 static struct s3c2410_dma_client s3c64xx_spi_dma_client = {
291 .name = "samsung-spi-dma",
292 };
293
294 static void prepare_dma(struct s3c64xx_spi_dma_data *dma,
295 unsigned len, dma_addr_t buf)
296 {
297 struct s3c64xx_spi_driver_data *sdd;
298 struct samsung_dma_prep info;
299 struct samsung_dma_config config;
300
301 if (dma->direction == DMA_DEV_TO_MEM) {
302 sdd = container_of((void *)dma,
303 struct s3c64xx_spi_driver_data, rx_dma);
304 config.direction = sdd->rx_dma.direction;
305 config.fifo = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
306 config.width = sdd->cur_bpw / 8;
307 sdd->ops->config((enum dma_ch)sdd->rx_dma.ch, &config);
308 } else {
309 sdd = container_of((void *)dma,
310 struct s3c64xx_spi_driver_data, tx_dma);
311 config.direction = sdd->tx_dma.direction;
312 config.fifo = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
313 config.width = sdd->cur_bpw / 8;
314 sdd->ops->config((enum dma_ch)sdd->tx_dma.ch, &config);
315 }
316
317 info.cap = DMA_SLAVE;
318 info.len = len;
319 info.fp = s3c64xx_spi_dmacb;
320 info.fp_param = dma;
321 info.direction = dma->direction;
322 info.buf = buf;
323
324 sdd->ops->prepare((enum dma_ch)dma->ch, &info);
325 sdd->ops->trigger((enum dma_ch)dma->ch);
326 }
327
328 static int acquire_dma(struct s3c64xx_spi_driver_data *sdd)
329 {
330 struct samsung_dma_req req;
331 struct device *dev = &sdd->pdev->dev;
332
333 sdd->ops = samsung_dma_get_ops();
334
335 req.cap = DMA_SLAVE;
336 req.client = &s3c64xx_spi_dma_client;
337
338 sdd->rx_dma.ch = (struct dma_chan *)(unsigned long)sdd->ops->request(
339 sdd->rx_dma.dmach, &req, dev, "rx");
340 sdd->tx_dma.ch = (struct dma_chan *)(unsigned long)sdd->ops->request(
341 sdd->tx_dma.dmach, &req, dev, "tx");
342
343 return 1;
344 }
345
346 static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
347 {
348 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
349
350 /*
351 * If DMA resource was not available during
352 * probe, no need to continue with dma requests
353 * else Acquire DMA channels
354 */
355 while (!is_polling(sdd) && !acquire_dma(sdd))
356 usleep_range(10000, 11000);
357
358 return 0;
359 }
360
361 static int s3c64xx_spi_unprepare_transfer(struct spi_master *spi)
362 {
363 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
364
365 /* Free DMA channels */
366 if (!is_polling(sdd)) {
367 sdd->ops->release((enum dma_ch)sdd->rx_dma.ch,
368 &s3c64xx_spi_dma_client);
369 sdd->ops->release((enum dma_ch)sdd->tx_dma.ch,
370 &s3c64xx_spi_dma_client);
371 }
372
373 return 0;
374 }
375
376 static void s3c64xx_spi_dma_stop(struct s3c64xx_spi_driver_data *sdd,
377 struct s3c64xx_spi_dma_data *dma)
378 {
379 sdd->ops->stop((enum dma_ch)dma->ch);
380 }
381 #else
382
383 static void prepare_dma(struct s3c64xx_spi_dma_data *dma,
384 unsigned len, dma_addr_t buf)
385 {
386 struct s3c64xx_spi_driver_data *sdd;
387 struct dma_slave_config config;
388 struct dma_async_tx_descriptor *desc;
389
390 memset(&config, 0, sizeof(config));
391
392 if (dma->direction == DMA_DEV_TO_MEM) {
393 sdd = container_of((void *)dma,
394 struct s3c64xx_spi_driver_data, rx_dma);
395 config.direction = dma->direction;
396 config.src_addr = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
397 config.src_addr_width = sdd->cur_bpw / 8;
398 config.src_maxburst = 1;
399 dmaengine_slave_config(dma->ch, &config);
400 } else {
401 sdd = container_of((void *)dma,
402 struct s3c64xx_spi_driver_data, tx_dma);
403 config.direction = dma->direction;
404 config.dst_addr = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
405 config.dst_addr_width = sdd->cur_bpw / 8;
406 config.dst_maxburst = 1;
407 dmaengine_slave_config(dma->ch, &config);
408 }
409
410 desc = dmaengine_prep_slave_single(dma->ch, buf, len,
411 dma->direction, DMA_PREP_INTERRUPT);
412
413 desc->callback = s3c64xx_spi_dmacb;
414 desc->callback_param = dma;
415
416 dmaengine_submit(desc);
417 dma_async_issue_pending(dma->ch);
418 }
419
420 static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
421 {
422 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
423 dma_filter_fn filter = sdd->cntrlr_info->filter;
424 struct device *dev = &sdd->pdev->dev;
425 dma_cap_mask_t mask;
426 int ret;
427
428 if (!is_polling(sdd)) {
429 dma_cap_zero(mask);
430 dma_cap_set(DMA_SLAVE, mask);
431
432 /* Acquire DMA channels */
433 sdd->rx_dma.ch = dma_request_slave_channel_compat(mask, filter,
434 (void *)sdd->rx_dma.dmach, dev, "rx");
435 if (!sdd->rx_dma.ch) {
436 dev_err(dev, "Failed to get RX DMA channel\n");
437 ret = -EBUSY;
438 goto out;
439 }
440
441 sdd->tx_dma.ch = dma_request_slave_channel_compat(mask, filter,
442 (void *)sdd->tx_dma.dmach, dev, "tx");
443 if (!sdd->tx_dma.ch) {
444 dev_err(dev, "Failed to get TX DMA channel\n");
445 ret = -EBUSY;
446 goto out_rx;
447 }
448 }
449
450 ret = pm_runtime_get_sync(&sdd->pdev->dev);
451 if (ret < 0) {
452 dev_err(dev, "Failed to enable device: %d\n", ret);
453 goto out_tx;
454 }
455
456 return 0;
457
458 out_tx:
459 dma_release_channel(sdd->tx_dma.ch);
460 out_rx:
461 dma_release_channel(sdd->rx_dma.ch);
462 out:
463 return ret;
464 }
465
466 static int s3c64xx_spi_unprepare_transfer(struct spi_master *spi)
467 {
468 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
469
470 /* Free DMA channels */
471 if (!is_polling(sdd)) {
472 dma_release_channel(sdd->rx_dma.ch);
473 dma_release_channel(sdd->tx_dma.ch);
474 }
475
476 pm_runtime_put(&sdd->pdev->dev);
477 return 0;
478 }
479
480 static void s3c64xx_spi_dma_stop(struct s3c64xx_spi_driver_data *sdd,
481 struct s3c64xx_spi_dma_data *dma)
482 {
483 dmaengine_terminate_all(dma->ch);
484 }
485 #endif
486
487 static void enable_datapath(struct s3c64xx_spi_driver_data *sdd,
488 struct spi_device *spi,
489 struct spi_transfer *xfer, int dma_mode)
490 {
491 void __iomem *regs = sdd->regs;
492 u32 modecfg, chcfg;
493
494 modecfg = readl(regs + S3C64XX_SPI_MODE_CFG);
495 modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
496
497 chcfg = readl(regs + S3C64XX_SPI_CH_CFG);
498 chcfg &= ~S3C64XX_SPI_CH_TXCH_ON;
499
500 if (dma_mode) {
501 chcfg &= ~S3C64XX_SPI_CH_RXCH_ON;
502 } else {
503 /* Always shift in data in FIFO, even if xfer is Tx only,
504 * this helps setting PCKT_CNT value for generating clocks
505 * as exactly needed.
506 */
507 chcfg |= S3C64XX_SPI_CH_RXCH_ON;
508 writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
509 | S3C64XX_SPI_PACKET_CNT_EN,
510 regs + S3C64XX_SPI_PACKET_CNT);
511 }
512
513 if (xfer->tx_buf != NULL) {
514 sdd->state |= TXBUSY;
515 chcfg |= S3C64XX_SPI_CH_TXCH_ON;
516 if (dma_mode) {
517 modecfg |= S3C64XX_SPI_MODE_TXDMA_ON;
518 prepare_dma(&sdd->tx_dma, xfer->len, xfer->tx_dma);
519 } else {
520 switch (sdd->cur_bpw) {
521 case 32:
522 iowrite32_rep(regs + S3C64XX_SPI_TX_DATA,
523 xfer->tx_buf, xfer->len / 4);
524 break;
525 case 16:
526 iowrite16_rep(regs + S3C64XX_SPI_TX_DATA,
527 xfer->tx_buf, xfer->len / 2);
528 break;
529 default:
530 iowrite8_rep(regs + S3C64XX_SPI_TX_DATA,
531 xfer->tx_buf, xfer->len);
532 break;
533 }
534 }
535 }
536
537 if (xfer->rx_buf != NULL) {
538 sdd->state |= RXBUSY;
539
540 if (sdd->port_conf->high_speed && sdd->cur_speed >= 30000000UL
541 && !(sdd->cur_mode & SPI_CPHA))
542 chcfg |= S3C64XX_SPI_CH_HS_EN;
543
544 if (dma_mode) {
545 modecfg |= S3C64XX_SPI_MODE_RXDMA_ON;
546 chcfg |= S3C64XX_SPI_CH_RXCH_ON;
547 writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
548 | S3C64XX_SPI_PACKET_CNT_EN,
549 regs + S3C64XX_SPI_PACKET_CNT);
550 prepare_dma(&sdd->rx_dma, xfer->len, xfer->rx_dma);
551 }
552 }
553
554 writel(modecfg, regs + S3C64XX_SPI_MODE_CFG);
555 writel(chcfg, regs + S3C64XX_SPI_CH_CFG);
556 }
557
558 static inline void enable_cs(struct s3c64xx_spi_driver_data *sdd,
559 struct spi_device *spi)
560 {
561 if (sdd->tgl_spi != NULL) { /* If last device toggled after mssg */
562 if (sdd->tgl_spi != spi) { /* if last mssg on diff device */
563 /* Deselect the last toggled device */
564 if (spi->cs_gpio >= 0)
565 gpio_set_value(spi->cs_gpio,
566 spi->mode & SPI_CS_HIGH ? 0 : 1);
567 }
568 sdd->tgl_spi = NULL;
569 }
570
571 if (spi->cs_gpio >= 0)
572 gpio_set_value(spi->cs_gpio, spi->mode & SPI_CS_HIGH ? 1 : 0);
573 }
574
575 static u32 s3c64xx_spi_wait_for_timeout(struct s3c64xx_spi_driver_data *sdd,
576 int timeout_ms)
577 {
578 void __iomem *regs = sdd->regs;
579 unsigned long val = 1;
580 u32 status;
581
582 /* max fifo depth available */
583 u32 max_fifo = (FIFO_LVL_MASK(sdd) >> 1) + 1;
584
585 if (timeout_ms)
586 val = msecs_to_loops(timeout_ms);
587
588 do {
589 status = readl(regs + S3C64XX_SPI_STATUS);
590 } while (RX_FIFO_LVL(status, sdd) < max_fifo && --val);
591
592 /* return the actual received data length */
593 return RX_FIFO_LVL(status, sdd);
594 }
595
596 static int wait_for_xfer(struct s3c64xx_spi_driver_data *sdd,
597 struct spi_transfer *xfer, int dma_mode)
598 {
599 void __iomem *regs = sdd->regs;
600 unsigned long val;
601 int ms;
602
603 /* millisecs to xfer 'len' bytes @ 'cur_speed' */
604 ms = xfer->len * 8 * 1000 / sdd->cur_speed;
605 ms += 10; /* some tolerance */
606
607 if (dma_mode) {
608 val = msecs_to_jiffies(ms) + 10;
609 val = wait_for_completion_timeout(&sdd->xfer_completion, val);
610 } else {
611 u32 status;
612 val = msecs_to_loops(ms);
613 do {
614 status = readl(regs + S3C64XX_SPI_STATUS);
615 } while (RX_FIFO_LVL(status, sdd) < xfer->len && --val);
616 }
617
618 if (dma_mode) {
619 u32 status;
620
621 /*
622 * If the previous xfer was completed within timeout, then
623 * proceed further else return -EIO.
624 * DmaTx returns after simply writing data in the FIFO,
625 * w/o waiting for real transmission on the bus to finish.
626 * DmaRx returns only after Dma read data from FIFO which
627 * needs bus transmission to finish, so we don't worry if
628 * Xfer involved Rx(with or without Tx).
629 */
630 if (val && !xfer->rx_buf) {
631 val = msecs_to_loops(10);
632 status = readl(regs + S3C64XX_SPI_STATUS);
633 while ((TX_FIFO_LVL(status, sdd)
634 || !S3C64XX_SPI_ST_TX_DONE(status, sdd))
635 && --val) {
636 cpu_relax();
637 status = readl(regs + S3C64XX_SPI_STATUS);
638 }
639
640 }
641
642 /* If timed out while checking rx/tx status return error */
643 if (!val)
644 return -EIO;
645 } else {
646 int loops;
647 u32 cpy_len;
648 u8 *buf;
649
650 /* If it was only Tx */
651 if (!xfer->rx_buf) {
652 sdd->state &= ~TXBUSY;
653 return 0;
654 }
655
656 /*
657 * If the receive length is bigger than the controller fifo
658 * size, calculate the loops and read the fifo as many times.
659 * loops = length / max fifo size (calculated by using the
660 * fifo mask).
661 * For any size less than the fifo size the below code is
662 * executed atleast once.
663 */
664 loops = xfer->len / ((FIFO_LVL_MASK(sdd) >> 1) + 1);
665 buf = xfer->rx_buf;
666 do {
667 /* wait for data to be received in the fifo */
668 cpy_len = s3c64xx_spi_wait_for_timeout(sdd,
669 (loops ? ms : 0));
670
671 switch (sdd->cur_bpw) {
672 case 32:
673 ioread32_rep(regs + S3C64XX_SPI_RX_DATA,
674 buf, cpy_len / 4);
675 break;
676 case 16:
677 ioread16_rep(regs + S3C64XX_SPI_RX_DATA,
678 buf, cpy_len / 2);
679 break;
680 default:
681 ioread8_rep(regs + S3C64XX_SPI_RX_DATA,
682 buf, cpy_len);
683 break;
684 }
685
686 buf = buf + cpy_len;
687 } while (loops--);
688 sdd->state &= ~RXBUSY;
689 }
690
691 return 0;
692 }
693
694 static inline void disable_cs(struct s3c64xx_spi_driver_data *sdd,
695 struct spi_device *spi)
696 {
697 if (sdd->tgl_spi == spi)
698 sdd->tgl_spi = NULL;
699
700 if (spi->cs_gpio >= 0)
701 gpio_set_value(spi->cs_gpio, spi->mode & SPI_CS_HIGH ? 0 : 1);
702 }
703
704 static void s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
705 {
706 void __iomem *regs = sdd->regs;
707 u32 val;
708
709 /* Disable Clock */
710 if (sdd->port_conf->clk_from_cmu) {
711 clk_disable_unprepare(sdd->src_clk);
712 } else {
713 val = readl(regs + S3C64XX_SPI_CLK_CFG);
714 val &= ~S3C64XX_SPI_ENCLK_ENABLE;
715 writel(val, regs + S3C64XX_SPI_CLK_CFG);
716 }
717
718 /* Set Polarity and Phase */
719 val = readl(regs + S3C64XX_SPI_CH_CFG);
720 val &= ~(S3C64XX_SPI_CH_SLAVE |
721 S3C64XX_SPI_CPOL_L |
722 S3C64XX_SPI_CPHA_B);
723
724 if (sdd->cur_mode & SPI_CPOL)
725 val |= S3C64XX_SPI_CPOL_L;
726
727 if (sdd->cur_mode & SPI_CPHA)
728 val |= S3C64XX_SPI_CPHA_B;
729
730 writel(val, regs + S3C64XX_SPI_CH_CFG);
731
732 /* Set Channel & DMA Mode */
733 val = readl(regs + S3C64XX_SPI_MODE_CFG);
734 val &= ~(S3C64XX_SPI_MODE_BUS_TSZ_MASK
735 | S3C64XX_SPI_MODE_CH_TSZ_MASK);
736
737 switch (sdd->cur_bpw) {
738 case 32:
739 val |= S3C64XX_SPI_MODE_BUS_TSZ_WORD;
740 val |= S3C64XX_SPI_MODE_CH_TSZ_WORD;
741 break;
742 case 16:
743 val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD;
744 val |= S3C64XX_SPI_MODE_CH_TSZ_HALFWORD;
745 break;
746 default:
747 val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE;
748 val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE;
749 break;
750 }
751
752 writel(val, regs + S3C64XX_SPI_MODE_CFG);
753
754 if (sdd->port_conf->clk_from_cmu) {
755 /* Configure Clock */
756 /* There is half-multiplier before the SPI */
757 clk_set_rate(sdd->src_clk, sdd->cur_speed * 2);
758 /* Enable Clock */
759 clk_prepare_enable(sdd->src_clk);
760 } else {
761 /* Configure Clock */
762 val = readl(regs + S3C64XX_SPI_CLK_CFG);
763 val &= ~S3C64XX_SPI_PSR_MASK;
764 val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / 2 - 1)
765 & S3C64XX_SPI_PSR_MASK);
766 writel(val, regs + S3C64XX_SPI_CLK_CFG);
767
768 /* Enable Clock */
769 val = readl(regs + S3C64XX_SPI_CLK_CFG);
770 val |= S3C64XX_SPI_ENCLK_ENABLE;
771 writel(val, regs + S3C64XX_SPI_CLK_CFG);
772 }
773 }
774
775 #define XFER_DMAADDR_INVALID DMA_BIT_MASK(32)
776
777 static int s3c64xx_spi_map_mssg(struct s3c64xx_spi_driver_data *sdd,
778 struct spi_message *msg)
779 {
780 struct device *dev = &sdd->pdev->dev;
781 struct spi_transfer *xfer;
782
783 if (is_polling(sdd) || msg->is_dma_mapped)
784 return 0;
785
786 /* First mark all xfer unmapped */
787 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
788 xfer->rx_dma = XFER_DMAADDR_INVALID;
789 xfer->tx_dma = XFER_DMAADDR_INVALID;
790 }
791
792 /* Map until end or first fail */
793 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
794
795 if (xfer->len <= ((FIFO_LVL_MASK(sdd) >> 1) + 1))
796 continue;
797
798 if (xfer->tx_buf != NULL) {
799 xfer->tx_dma = dma_map_single(dev,
800 (void *)xfer->tx_buf, xfer->len,
801 DMA_TO_DEVICE);
802 if (dma_mapping_error(dev, xfer->tx_dma)) {
803 dev_err(dev, "dma_map_single Tx failed\n");
804 xfer->tx_dma = XFER_DMAADDR_INVALID;
805 return -ENOMEM;
806 }
807 }
808
809 if (xfer->rx_buf != NULL) {
810 xfer->rx_dma = dma_map_single(dev, xfer->rx_buf,
811 xfer->len, DMA_FROM_DEVICE);
812 if (dma_mapping_error(dev, xfer->rx_dma)) {
813 dev_err(dev, "dma_map_single Rx failed\n");
814 dma_unmap_single(dev, xfer->tx_dma,
815 xfer->len, DMA_TO_DEVICE);
816 xfer->tx_dma = XFER_DMAADDR_INVALID;
817 xfer->rx_dma = XFER_DMAADDR_INVALID;
818 return -ENOMEM;
819 }
820 }
821 }
822
823 return 0;
824 }
825
826 static void s3c64xx_spi_unmap_mssg(struct s3c64xx_spi_driver_data *sdd,
827 struct spi_message *msg)
828 {
829 struct device *dev = &sdd->pdev->dev;
830 struct spi_transfer *xfer;
831
832 if (is_polling(sdd) || msg->is_dma_mapped)
833 return;
834
835 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
836
837 if (xfer->len <= ((FIFO_LVL_MASK(sdd) >> 1) + 1))
838 continue;
839
840 if (xfer->rx_buf != NULL
841 && xfer->rx_dma != XFER_DMAADDR_INVALID)
842 dma_unmap_single(dev, xfer->rx_dma,
843 xfer->len, DMA_FROM_DEVICE);
844
845 if (xfer->tx_buf != NULL
846 && xfer->tx_dma != XFER_DMAADDR_INVALID)
847 dma_unmap_single(dev, xfer->tx_dma,
848 xfer->len, DMA_TO_DEVICE);
849 }
850 }
851
852 static int s3c64xx_spi_prepare_message(struct spi_master *master,
853 struct spi_message *msg)
854 {
855 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
856 struct spi_device *spi = msg->spi;
857 struct s3c64xx_spi_csinfo *cs = spi->controller_data;
858
859 /* If Master's(controller) state differs from that needed by Slave */
860 if (sdd->cur_speed != spi->max_speed_hz
861 || sdd->cur_mode != spi->mode
862 || sdd->cur_bpw != spi->bits_per_word) {
863 sdd->cur_bpw = spi->bits_per_word;
864 sdd->cur_speed = spi->max_speed_hz;
865 sdd->cur_mode = spi->mode;
866 s3c64xx_spi_config(sdd);
867 }
868
869 /* Map all the transfers if needed */
870 if (s3c64xx_spi_map_mssg(sdd, msg)) {
871 dev_err(&spi->dev,
872 "Xfer: Unable to map message buffers!\n");
873 return -ENOMEM;
874 }
875
876 /* Configure feedback delay */
877 writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK);
878
879 return 0;
880 }
881
882 static int s3c64xx_spi_transfer_one(struct spi_master *master,
883 struct spi_device *spi,
884 struct spi_transfer *xfer)
885 {
886 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
887 int status;
888 u32 speed;
889 u8 bpw;
890 unsigned long flags;
891 int use_dma;
892
893 reinit_completion(&sdd->xfer_completion);
894
895 /* Only BPW and Speed may change across transfers */
896 bpw = xfer->bits_per_word;
897 speed = xfer->speed_hz ? : spi->max_speed_hz;
898
899 if (xfer->len % (bpw / 8)) {
900 dev_err(&spi->dev,
901 "Xfer length(%u) not a multiple of word size(%u)\n",
902 xfer->len, bpw / 8);
903 return -EIO;
904 }
905
906 if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) {
907 sdd->cur_bpw = bpw;
908 sdd->cur_speed = speed;
909 s3c64xx_spi_config(sdd);
910 }
911
912 /* Polling method for xfers not bigger than FIFO capacity */
913 use_dma = 0;
914 if (!is_polling(sdd) &&
915 (sdd->rx_dma.ch && sdd->tx_dma.ch &&
916 (xfer->len > ((FIFO_LVL_MASK(sdd) >> 1) + 1))))
917 use_dma = 1;
918
919 spin_lock_irqsave(&sdd->lock, flags);
920
921 /* Pending only which is to be done */
922 sdd->state &= ~RXBUSY;
923 sdd->state &= ~TXBUSY;
924
925 enable_datapath(sdd, spi, xfer, use_dma);
926
927 /* Start the signals */
928 writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
929
930 spin_unlock_irqrestore(&sdd->lock, flags);
931
932 status = wait_for_xfer(sdd, xfer, use_dma);
933
934 if (status) {
935 dev_err(&spi->dev, "I/O Error: rx-%d tx-%d res:rx-%c tx-%c len-%d\n",
936 xfer->rx_buf ? 1 : 0, xfer->tx_buf ? 1 : 0,
937 (sdd->state & RXBUSY) ? 'f' : 'p',
938 (sdd->state & TXBUSY) ? 'f' : 'p',
939 xfer->len);
940
941 if (use_dma) {
942 if (xfer->tx_buf != NULL
943 && (sdd->state & TXBUSY))
944 s3c64xx_spi_dma_stop(sdd, &sdd->tx_dma);
945 if (xfer->rx_buf != NULL
946 && (sdd->state & RXBUSY))
947 s3c64xx_spi_dma_stop(sdd, &sdd->rx_dma);
948 }
949 } else {
950 flush_fifo(sdd);
951 }
952
953 return status;
954 }
955
956 static int s3c64xx_spi_unprepare_message(struct spi_master *master,
957 struct spi_message *msg)
958 {
959 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
960
961 s3c64xx_spi_unmap_mssg(sdd, msg);
962
963 return 0;
964 }
965
966 static struct s3c64xx_spi_csinfo *s3c64xx_get_slave_ctrldata(
967 struct spi_device *spi)
968 {
969 struct s3c64xx_spi_csinfo *cs;
970 struct device_node *slave_np, *data_np = NULL;
971 struct s3c64xx_spi_driver_data *sdd;
972 u32 fb_delay = 0;
973
974 sdd = spi_master_get_devdata(spi->master);
975 slave_np = spi->dev.of_node;
976 if (!slave_np) {
977 dev_err(&spi->dev, "device node not found\n");
978 return ERR_PTR(-EINVAL);
979 }
980
981 data_np = of_get_child_by_name(slave_np, "controller-data");
982 if (!data_np) {
983 dev_err(&spi->dev, "child node 'controller-data' not found\n");
984 return ERR_PTR(-EINVAL);
985 }
986
987 cs = kzalloc(sizeof(*cs), GFP_KERNEL);
988 if (!cs) {
989 dev_err(&spi->dev, "could not allocate memory for controller data\n");
990 of_node_put(data_np);
991 return ERR_PTR(-ENOMEM);
992 }
993
994 /* The CS line is asserted/deasserted by the gpio pin */
995 if (sdd->cs_gpio)
996 cs->line = of_get_named_gpio(data_np, "cs-gpio", 0);
997
998 if (!gpio_is_valid(cs->line)) {
999 dev_err(&spi->dev, "chip select gpio is not specified or invalid\n");
1000 kfree(cs);
1001 of_node_put(data_np);
1002 return ERR_PTR(-EINVAL);
1003 }
1004
1005 of_property_read_u32(data_np, "samsung,spi-feedback-delay", &fb_delay);
1006 cs->fb_delay = fb_delay;
1007 of_node_put(data_np);
1008 return cs;
1009 }
1010
1011 /*
1012 * Here we only check the validity of requested configuration
1013 * and save the configuration in a local data-structure.
1014 * The controller is actually configured only just before we
1015 * get a message to transfer.
1016 */
1017 static int s3c64xx_spi_setup(struct spi_device *spi)
1018 {
1019 struct s3c64xx_spi_csinfo *cs = spi->controller_data;
1020 struct s3c64xx_spi_driver_data *sdd;
1021 struct s3c64xx_spi_info *sci;
1022 int err;
1023
1024 sdd = spi_master_get_devdata(spi->master);
1025 if (!cs && spi->dev.of_node) {
1026 cs = s3c64xx_get_slave_ctrldata(spi);
1027 spi->controller_data = cs;
1028 }
1029
1030 if (IS_ERR_OR_NULL(cs)) {
1031 dev_err(&spi->dev, "No CS for SPI(%d)\n", spi->chip_select);
1032 return -ENODEV;
1033 }
1034
1035 if (!spi_get_ctldata(spi)) {
1036 /* Request gpio only if cs line is asserted by gpio pins */
1037 if (sdd->cs_gpio) {
1038 err = gpio_request_one(cs->line, GPIOF_OUT_INIT_HIGH,
1039 dev_name(&spi->dev));
1040 if (err) {
1041 dev_err(&spi->dev,
1042 "Failed to get /CS gpio [%d]: %d\n",
1043 cs->line, err);
1044 goto err_gpio_req;
1045 }
1046
1047 spi->cs_gpio = cs->line;
1048 }
1049
1050 spi_set_ctldata(spi, cs);
1051 }
1052
1053 sci = sdd->cntrlr_info;
1054
1055 pm_runtime_get_sync(&sdd->pdev->dev);
1056
1057 /* Check if we can provide the requested rate */
1058 if (!sdd->port_conf->clk_from_cmu) {
1059 u32 psr, speed;
1060
1061 /* Max possible */
1062 speed = clk_get_rate(sdd->src_clk) / 2 / (0 + 1);
1063
1064 if (spi->max_speed_hz > speed)
1065 spi->max_speed_hz = speed;
1066
1067 psr = clk_get_rate(sdd->src_clk) / 2 / spi->max_speed_hz - 1;
1068 psr &= S3C64XX_SPI_PSR_MASK;
1069 if (psr == S3C64XX_SPI_PSR_MASK)
1070 psr--;
1071
1072 speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
1073 if (spi->max_speed_hz < speed) {
1074 if (psr+1 < S3C64XX_SPI_PSR_MASK) {
1075 psr++;
1076 } else {
1077 err = -EINVAL;
1078 goto setup_exit;
1079 }
1080 }
1081
1082 speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
1083 if (spi->max_speed_hz >= speed) {
1084 spi->max_speed_hz = speed;
1085 } else {
1086 dev_err(&spi->dev, "Can't set %dHz transfer speed\n",
1087 spi->max_speed_hz);
1088 err = -EINVAL;
1089 goto setup_exit;
1090 }
1091 }
1092
1093 pm_runtime_put(&sdd->pdev->dev);
1094 writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
1095 disable_cs(sdd, spi);
1096 return 0;
1097
1098 setup_exit:
1099 pm_runtime_put(&sdd->pdev->dev);
1100 /* setup() returns with device de-selected */
1101 writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
1102 disable_cs(sdd, spi);
1103
1104 gpio_free(cs->line);
1105 spi_set_ctldata(spi, NULL);
1106
1107 err_gpio_req:
1108 if (spi->dev.of_node)
1109 kfree(cs);
1110
1111 return err;
1112 }
1113
1114 static void s3c64xx_spi_cleanup(struct spi_device *spi)
1115 {
1116 struct s3c64xx_spi_csinfo *cs = spi_get_ctldata(spi);
1117 struct s3c64xx_spi_driver_data *sdd;
1118
1119 sdd = spi_master_get_devdata(spi->master);
1120 if (spi->cs_gpio) {
1121 gpio_free(spi->cs_gpio);
1122 if (spi->dev.of_node)
1123 kfree(cs);
1124 }
1125 spi_set_ctldata(spi, NULL);
1126 }
1127
1128 static irqreturn_t s3c64xx_spi_irq(int irq, void *data)
1129 {
1130 struct s3c64xx_spi_driver_data *sdd = data;
1131 struct spi_master *spi = sdd->master;
1132 unsigned int val, clr = 0;
1133
1134 val = readl(sdd->regs + S3C64XX_SPI_STATUS);
1135
1136 if (val & S3C64XX_SPI_ST_RX_OVERRUN_ERR) {
1137 clr = S3C64XX_SPI_PND_RX_OVERRUN_CLR;
1138 dev_err(&spi->dev, "RX overrun\n");
1139 }
1140 if (val & S3C64XX_SPI_ST_RX_UNDERRUN_ERR) {
1141 clr |= S3C64XX_SPI_PND_RX_UNDERRUN_CLR;
1142 dev_err(&spi->dev, "RX underrun\n");
1143 }
1144 if (val & S3C64XX_SPI_ST_TX_OVERRUN_ERR) {
1145 clr |= S3C64XX_SPI_PND_TX_OVERRUN_CLR;
1146 dev_err(&spi->dev, "TX overrun\n");
1147 }
1148 if (val & S3C64XX_SPI_ST_TX_UNDERRUN_ERR) {
1149 clr |= S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
1150 dev_err(&spi->dev, "TX underrun\n");
1151 }
1152
1153 /* Clear the pending irq by setting and then clearing it */
1154 writel(clr, sdd->regs + S3C64XX_SPI_PENDING_CLR);
1155 writel(0, sdd->regs + S3C64XX_SPI_PENDING_CLR);
1156
1157 return IRQ_HANDLED;
1158 }
1159
1160 static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd, int channel)
1161 {
1162 struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1163 void __iomem *regs = sdd->regs;
1164 unsigned int val;
1165
1166 sdd->cur_speed = 0;
1167
1168 writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
1169
1170 /* Disable Interrupts - we use Polling if not DMA mode */
1171 writel(0, regs + S3C64XX_SPI_INT_EN);
1172
1173 if (!sdd->port_conf->clk_from_cmu)
1174 writel(sci->src_clk_nr << S3C64XX_SPI_CLKSEL_SRCSHFT,
1175 regs + S3C64XX_SPI_CLK_CFG);
1176 writel(0, regs + S3C64XX_SPI_MODE_CFG);
1177 writel(0, regs + S3C64XX_SPI_PACKET_CNT);
1178
1179 /* Clear any irq pending bits, should set and clear the bits */
1180 val = S3C64XX_SPI_PND_RX_OVERRUN_CLR |
1181 S3C64XX_SPI_PND_RX_UNDERRUN_CLR |
1182 S3C64XX_SPI_PND_TX_OVERRUN_CLR |
1183 S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
1184 writel(val, regs + S3C64XX_SPI_PENDING_CLR);
1185 writel(0, regs + S3C64XX_SPI_PENDING_CLR);
1186
1187 writel(0, regs + S3C64XX_SPI_SWAP_CFG);
1188
1189 val = readl(regs + S3C64XX_SPI_MODE_CFG);
1190 val &= ~S3C64XX_SPI_MODE_4BURST;
1191 val &= ~(S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
1192 val |= (S3C64XX_SPI_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
1193 writel(val, regs + S3C64XX_SPI_MODE_CFG);
1194
1195 flush_fifo(sdd);
1196 }
1197
1198 #ifdef CONFIG_OF
1199 static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
1200 {
1201 struct s3c64xx_spi_info *sci;
1202 u32 temp;
1203
1204 sci = devm_kzalloc(dev, sizeof(*sci), GFP_KERNEL);
1205 if (!sci) {
1206 dev_err(dev, "memory allocation for spi_info failed\n");
1207 return ERR_PTR(-ENOMEM);
1208 }
1209
1210 if (of_property_read_u32(dev->of_node, "samsung,spi-src-clk", &temp)) {
1211 dev_warn(dev, "spi bus clock parent not specified, using clock at index 0 as parent\n");
1212 sci->src_clk_nr = 0;
1213 } else {
1214 sci->src_clk_nr = temp;
1215 }
1216
1217 if (of_property_read_u32(dev->of_node, "num-cs", &temp)) {
1218 dev_warn(dev, "number of chip select lines not specified, assuming 1 chip select line\n");
1219 sci->num_cs = 1;
1220 } else {
1221 sci->num_cs = temp;
1222 }
1223
1224 return sci;
1225 }
1226 #else
1227 static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
1228 {
1229 return dev_get_platdata(dev);
1230 }
1231 #endif
1232
1233 static const struct of_device_id s3c64xx_spi_dt_match[];
1234
1235 static inline struct s3c64xx_spi_port_config *s3c64xx_spi_get_port_config(
1236 struct platform_device *pdev)
1237 {
1238 #ifdef CONFIG_OF
1239 if (pdev->dev.of_node) {
1240 const struct of_device_id *match;
1241 match = of_match_node(s3c64xx_spi_dt_match, pdev->dev.of_node);
1242 return (struct s3c64xx_spi_port_config *)match->data;
1243 }
1244 #endif
1245 return (struct s3c64xx_spi_port_config *)
1246 platform_get_device_id(pdev)->driver_data;
1247 }
1248
1249 static int s3c64xx_spi_probe(struct platform_device *pdev)
1250 {
1251 struct resource *mem_res;
1252 struct resource *res;
1253 struct s3c64xx_spi_driver_data *sdd;
1254 struct s3c64xx_spi_info *sci = dev_get_platdata(&pdev->dev);
1255 struct spi_master *master;
1256 int ret, irq;
1257 char clk_name[16];
1258
1259 if (!sci && pdev->dev.of_node) {
1260 sci = s3c64xx_spi_parse_dt(&pdev->dev);
1261 if (IS_ERR(sci))
1262 return PTR_ERR(sci);
1263 }
1264
1265 if (!sci) {
1266 dev_err(&pdev->dev, "platform_data missing!\n");
1267 return -ENODEV;
1268 }
1269
1270 mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1271 if (mem_res == NULL) {
1272 dev_err(&pdev->dev, "Unable to get SPI MEM resource\n");
1273 return -ENXIO;
1274 }
1275
1276 irq = platform_get_irq(pdev, 0);
1277 if (irq < 0) {
1278 dev_warn(&pdev->dev, "Failed to get IRQ: %d\n", irq);
1279 return irq;
1280 }
1281
1282 master = spi_alloc_master(&pdev->dev,
1283 sizeof(struct s3c64xx_spi_driver_data));
1284 if (master == NULL) {
1285 dev_err(&pdev->dev, "Unable to allocate SPI Master\n");
1286 return -ENOMEM;
1287 }
1288
1289 platform_set_drvdata(pdev, master);
1290
1291 sdd = spi_master_get_devdata(master);
1292 sdd->port_conf = s3c64xx_spi_get_port_config(pdev);
1293 sdd->master = master;
1294 sdd->cntrlr_info = sci;
1295 sdd->pdev = pdev;
1296 sdd->sfr_start = mem_res->start;
1297 sdd->cs_gpio = true;
1298 if (pdev->dev.of_node) {
1299 if (!of_find_property(pdev->dev.of_node, "cs-gpio", NULL))
1300 sdd->cs_gpio = false;
1301
1302 ret = of_alias_get_id(pdev->dev.of_node, "spi");
1303 if (ret < 0) {
1304 dev_err(&pdev->dev, "failed to get alias id, errno %d\n",
1305 ret);
1306 goto err0;
1307 }
1308 sdd->port_id = ret;
1309 } else {
1310 sdd->port_id = pdev->id;
1311 }
1312
1313 sdd->cur_bpw = 8;
1314
1315 if (!sdd->pdev->dev.of_node) {
1316 res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
1317 if (!res) {
1318 dev_warn(&pdev->dev, "Unable to get SPI tx dma resource. Switching to poll mode\n");
1319 sdd->port_conf->quirks = S3C64XX_SPI_QUIRK_POLL;
1320 } else
1321 sdd->tx_dma.dmach = res->start;
1322
1323 res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
1324 if (!res) {
1325 dev_warn(&pdev->dev, "Unable to get SPI rx dma resource. Switching to poll mode\n");
1326 sdd->port_conf->quirks = S3C64XX_SPI_QUIRK_POLL;
1327 } else
1328 sdd->rx_dma.dmach = res->start;
1329 }
1330
1331 sdd->tx_dma.direction = DMA_MEM_TO_DEV;
1332 sdd->rx_dma.direction = DMA_DEV_TO_MEM;
1333
1334 master->dev.of_node = pdev->dev.of_node;
1335 master->bus_num = sdd->port_id;
1336 master->setup = s3c64xx_spi_setup;
1337 master->cleanup = s3c64xx_spi_cleanup;
1338 master->prepare_transfer_hardware = s3c64xx_spi_prepare_transfer;
1339 master->prepare_message = s3c64xx_spi_prepare_message;
1340 master->transfer_one = s3c64xx_spi_transfer_one;
1341 master->unprepare_message = s3c64xx_spi_unprepare_message;
1342 master->unprepare_transfer_hardware = s3c64xx_spi_unprepare_transfer;
1343 master->num_chipselect = sci->num_cs;
1344 master->dma_alignment = 8;
1345 master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) |
1346 SPI_BPW_MASK(8);
1347 /* the spi->mode bits understood by this driver: */
1348 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1349 master->auto_runtime_pm = true;
1350
1351 sdd->regs = devm_ioremap_resource(&pdev->dev, mem_res);
1352 if (IS_ERR(sdd->regs)) {
1353 ret = PTR_ERR(sdd->regs);
1354 goto err0;
1355 }
1356
1357 if (sci->cfg_gpio && sci->cfg_gpio()) {
1358 dev_err(&pdev->dev, "Unable to config gpio\n");
1359 ret = -EBUSY;
1360 goto err0;
1361 }
1362
1363 /* Setup clocks */
1364 sdd->clk = devm_clk_get(&pdev->dev, "spi");
1365 if (IS_ERR(sdd->clk)) {
1366 dev_err(&pdev->dev, "Unable to acquire clock 'spi'\n");
1367 ret = PTR_ERR(sdd->clk);
1368 goto err0;
1369 }
1370
1371 if (clk_prepare_enable(sdd->clk)) {
1372 dev_err(&pdev->dev, "Couldn't enable clock 'spi'\n");
1373 ret = -EBUSY;
1374 goto err0;
1375 }
1376
1377 sprintf(clk_name, "spi_busclk%d", sci->src_clk_nr);
1378 sdd->src_clk = devm_clk_get(&pdev->dev, clk_name);
1379 if (IS_ERR(sdd->src_clk)) {
1380 dev_err(&pdev->dev,
1381 "Unable to acquire clock '%s'\n", clk_name);
1382 ret = PTR_ERR(sdd->src_clk);
1383 goto err2;
1384 }
1385
1386 if (clk_prepare_enable(sdd->src_clk)) {
1387 dev_err(&pdev->dev, "Couldn't enable clock '%s'\n", clk_name);
1388 ret = -EBUSY;
1389 goto err2;
1390 }
1391
1392 /* Setup Deufult Mode */
1393 s3c64xx_spi_hwinit(sdd, sdd->port_id);
1394
1395 spin_lock_init(&sdd->lock);
1396 init_completion(&sdd->xfer_completion);
1397
1398 ret = devm_request_irq(&pdev->dev, irq, s3c64xx_spi_irq, 0,
1399 "spi-s3c64xx", sdd);
1400 if (ret != 0) {
1401 dev_err(&pdev->dev, "Failed to request IRQ %d: %d\n",
1402 irq, ret);
1403 goto err3;
1404 }
1405
1406 writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
1407 S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
1408 sdd->regs + S3C64XX_SPI_INT_EN);
1409
1410 pm_runtime_set_active(&pdev->dev);
1411 pm_runtime_enable(&pdev->dev);
1412
1413 ret = devm_spi_register_master(&pdev->dev, master);
1414 if (ret != 0) {
1415 dev_err(&pdev->dev, "cannot register SPI master: %d\n", ret);
1416 goto err3;
1417 }
1418
1419 dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d with %d Slaves attached\n",
1420 sdd->port_id, master->num_chipselect);
1421 dev_dbg(&pdev->dev, "\tIOmem=[%pR]\tDMA=[Rx-%d, Tx-%d]\n",
1422 mem_res,
1423 sdd->rx_dma.dmach, sdd->tx_dma.dmach);
1424
1425 return 0;
1426
1427 err3:
1428 clk_disable_unprepare(sdd->src_clk);
1429 err2:
1430 clk_disable_unprepare(sdd->clk);
1431 err0:
1432 spi_master_put(master);
1433
1434 return ret;
1435 }
1436
1437 static int s3c64xx_spi_remove(struct platform_device *pdev)
1438 {
1439 struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
1440 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1441
1442 pm_runtime_disable(&pdev->dev);
1443
1444 writel(0, sdd->regs + S3C64XX_SPI_INT_EN);
1445
1446 clk_disable_unprepare(sdd->src_clk);
1447
1448 clk_disable_unprepare(sdd->clk);
1449
1450 return 0;
1451 }
1452
1453 #ifdef CONFIG_PM_SLEEP
1454 static int s3c64xx_spi_suspend(struct device *dev)
1455 {
1456 struct spi_master *master = dev_get_drvdata(dev);
1457 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1458
1459 int ret = spi_master_suspend(master);
1460 if (ret)
1461 return ret;
1462
1463 if (!pm_runtime_suspended(dev)) {
1464 clk_disable_unprepare(sdd->clk);
1465 clk_disable_unprepare(sdd->src_clk);
1466 }
1467
1468 sdd->cur_speed = 0; /* Output Clock is stopped */
1469
1470 return 0;
1471 }
1472
1473 static int s3c64xx_spi_resume(struct device *dev)
1474 {
1475 struct spi_master *master = dev_get_drvdata(dev);
1476 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1477 struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1478
1479 if (sci->cfg_gpio)
1480 sci->cfg_gpio();
1481
1482 if (!pm_runtime_suspended(dev)) {
1483 clk_prepare_enable(sdd->src_clk);
1484 clk_prepare_enable(sdd->clk);
1485 }
1486
1487 s3c64xx_spi_hwinit(sdd, sdd->port_id);
1488
1489 return spi_master_resume(master);
1490 }
1491 #endif /* CONFIG_PM_SLEEP */
1492
1493 #ifdef CONFIG_PM_RUNTIME
1494 static int s3c64xx_spi_runtime_suspend(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
1499 clk_disable_unprepare(sdd->clk);
1500 clk_disable_unprepare(sdd->src_clk);
1501
1502 return 0;
1503 }
1504
1505 static int s3c64xx_spi_runtime_resume(struct device *dev)
1506 {
1507 struct spi_master *master = dev_get_drvdata(dev);
1508 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1509 int ret;
1510
1511 ret = clk_prepare_enable(sdd->src_clk);
1512 if (ret != 0)
1513 return ret;
1514
1515 ret = clk_prepare_enable(sdd->clk);
1516 if (ret != 0) {
1517 clk_disable_unprepare(sdd->src_clk);
1518 return ret;
1519 }
1520
1521 return 0;
1522 }
1523 #endif /* CONFIG_PM_RUNTIME */
1524
1525 static const struct dev_pm_ops s3c64xx_spi_pm = {
1526 SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume)
1527 SET_RUNTIME_PM_OPS(s3c64xx_spi_runtime_suspend,
1528 s3c64xx_spi_runtime_resume, NULL)
1529 };
1530
1531 static struct s3c64xx_spi_port_config s3c2443_spi_port_config = {
1532 .fifo_lvl_mask = { 0x7f },
1533 .rx_lvl_offset = 13,
1534 .tx_st_done = 21,
1535 .high_speed = true,
1536 };
1537
1538 static struct s3c64xx_spi_port_config s3c6410_spi_port_config = {
1539 .fifo_lvl_mask = { 0x7f, 0x7F },
1540 .rx_lvl_offset = 13,
1541 .tx_st_done = 21,
1542 };
1543
1544 static struct s3c64xx_spi_port_config s5p64x0_spi_port_config = {
1545 .fifo_lvl_mask = { 0x1ff, 0x7F },
1546 .rx_lvl_offset = 15,
1547 .tx_st_done = 25,
1548 };
1549
1550 static struct s3c64xx_spi_port_config s5pc100_spi_port_config = {
1551 .fifo_lvl_mask = { 0x7f, 0x7F },
1552 .rx_lvl_offset = 13,
1553 .tx_st_done = 21,
1554 .high_speed = true,
1555 };
1556
1557 static struct s3c64xx_spi_port_config s5pv210_spi_port_config = {
1558 .fifo_lvl_mask = { 0x1ff, 0x7F },
1559 .rx_lvl_offset = 15,
1560 .tx_st_done = 25,
1561 .high_speed = true,
1562 };
1563
1564 static struct s3c64xx_spi_port_config exynos4_spi_port_config = {
1565 .fifo_lvl_mask = { 0x1ff, 0x7F, 0x7F },
1566 .rx_lvl_offset = 15,
1567 .tx_st_done = 25,
1568 .high_speed = true,
1569 .clk_from_cmu = true,
1570 };
1571
1572 static struct s3c64xx_spi_port_config exynos5440_spi_port_config = {
1573 .fifo_lvl_mask = { 0x1ff },
1574 .rx_lvl_offset = 15,
1575 .tx_st_done = 25,
1576 .high_speed = true,
1577 .clk_from_cmu = true,
1578 .quirks = S3C64XX_SPI_QUIRK_POLL,
1579 };
1580
1581 static struct platform_device_id s3c64xx_spi_driver_ids[] = {
1582 {
1583 .name = "s3c2443-spi",
1584 .driver_data = (kernel_ulong_t)&s3c2443_spi_port_config,
1585 }, {
1586 .name = "s3c6410-spi",
1587 .driver_data = (kernel_ulong_t)&s3c6410_spi_port_config,
1588 }, {
1589 .name = "s5p64x0-spi",
1590 .driver_data = (kernel_ulong_t)&s5p64x0_spi_port_config,
1591 }, {
1592 .name = "s5pc100-spi",
1593 .driver_data = (kernel_ulong_t)&s5pc100_spi_port_config,
1594 }, {
1595 .name = "s5pv210-spi",
1596 .driver_data = (kernel_ulong_t)&s5pv210_spi_port_config,
1597 }, {
1598 .name = "exynos4210-spi",
1599 .driver_data = (kernel_ulong_t)&exynos4_spi_port_config,
1600 },
1601 { },
1602 };
1603
1604 static const struct of_device_id s3c64xx_spi_dt_match[] = {
1605 { .compatible = "samsung,s3c2443-spi",
1606 .data = (void *)&s3c2443_spi_port_config,
1607 },
1608 { .compatible = "samsung,s3c6410-spi",
1609 .data = (void *)&s3c6410_spi_port_config,
1610 },
1611 { .compatible = "samsung,s5pc100-spi",
1612 .data = (void *)&s5pc100_spi_port_config,
1613 },
1614 { .compatible = "samsung,s5pv210-spi",
1615 .data = (void *)&s5pv210_spi_port_config,
1616 },
1617 { .compatible = "samsung,exynos4210-spi",
1618 .data = (void *)&exynos4_spi_port_config,
1619 },
1620 { .compatible = "samsung,exynos5440-spi",
1621 .data = (void *)&exynos5440_spi_port_config,
1622 },
1623 { },
1624 };
1625 MODULE_DEVICE_TABLE(of, s3c64xx_spi_dt_match);
1626
1627 static struct platform_driver s3c64xx_spi_driver = {
1628 .driver = {
1629 .name = "s3c64xx-spi",
1630 .owner = THIS_MODULE,
1631 .pm = &s3c64xx_spi_pm,
1632 .of_match_table = of_match_ptr(s3c64xx_spi_dt_match),
1633 },
1634 .probe = s3c64xx_spi_probe,
1635 .remove = s3c64xx_spi_remove,
1636 .id_table = s3c64xx_spi_driver_ids,
1637 };
1638 MODULE_ALIAS("platform:s3c64xx-spi");
1639
1640 module_platform_driver(s3c64xx_spi_driver);
1641
1642 MODULE_AUTHOR("Jaswinder Singh <jassi.brar@samsung.com>");
1643 MODULE_DESCRIPTION("S3C64XX SPI Controller Driver");
1644 MODULE_LICENSE("GPL");
Linux with added FPC-III support