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ARM: dts: imx27: Rename PWM devicetree node
[linux/fpc-iii.git] / drivers / spi / spi-s3c64xx.c
blob63e2070c6c14aa8e39a64a850248e07a38546708
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 * @queue: To log SPI xfer requests.
176 * @lock: Controller specific lock.
177 * @state: Set of FLAGS to indicate status.
178 * @rx_dmach: Controller's DMA channel for Rx.
179 * @tx_dmach: Controller's DMA channel for Tx.
180 * @sfr_start: BUS address of SPI controller regs.
181 * @regs: Pointer to ioremap'ed controller registers.
182 * @irq: interrupt
183 * @xfer_completion: To indicate completion of xfer task.
184 * @cur_mode: Stores the active configuration of the controller.
185 * @cur_bpw: Stores the active bits per word settings.
186 * @cur_speed: Stores the active xfer clock speed.
187 */
188 struct s3c64xx_spi_driver_data {
189 void __iomem *regs;
190 struct clk *clk;
191 struct clk *src_clk;
192 struct platform_device *pdev;
193 struct spi_master *master;
194 struct s3c64xx_spi_info *cntrlr_info;
195 struct spi_device *tgl_spi;
196 struct list_head queue;
197 spinlock_t lock;
198 unsigned long sfr_start;
199 struct completion xfer_completion;
200 unsigned state;
201 unsigned cur_mode, cur_bpw;
202 unsigned cur_speed;
203 struct s3c64xx_spi_dma_data rx_dma;
204 struct s3c64xx_spi_dma_data tx_dma;
205 #ifdef CONFIG_S3C_DMA
206 struct samsung_dma_ops *ops;
207 #endif
208 struct s3c64xx_spi_port_config *port_conf;
209 unsigned int port_id;
210 unsigned long gpios[4];
211 bool cs_gpio;
212 };
213
214 static void flush_fifo(struct s3c64xx_spi_driver_data *sdd)
215 {
216 void __iomem *regs = sdd->regs;
217 unsigned long loops;
218 u32 val;
219
220 writel(0, regs + S3C64XX_SPI_PACKET_CNT);
221
222 val = readl(regs + S3C64XX_SPI_CH_CFG);
223 val &= ~(S3C64XX_SPI_CH_RXCH_ON | S3C64XX_SPI_CH_TXCH_ON);
224 writel(val, regs + S3C64XX_SPI_CH_CFG);
225
226 val = readl(regs + S3C64XX_SPI_CH_CFG);
227 val |= S3C64XX_SPI_CH_SW_RST;
228 val &= ~S3C64XX_SPI_CH_HS_EN;
229 writel(val, regs + S3C64XX_SPI_CH_CFG);
230
231 /* Flush TxFIFO*/
232 loops = msecs_to_loops(1);
233 do {
234 val = readl(regs + S3C64XX_SPI_STATUS);
235 } while (TX_FIFO_LVL(val, sdd) && loops--);
236
237 if (loops == 0)
238 dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n");
239
240 /* Flush RxFIFO*/
241 loops = msecs_to_loops(1);
242 do {
243 val = readl(regs + S3C64XX_SPI_STATUS);
244 if (RX_FIFO_LVL(val, sdd))
245 readl(regs + S3C64XX_SPI_RX_DATA);
246 else
247 break;
248 } while (loops--);
249
250 if (loops == 0)
251 dev_warn(&sdd->pdev->dev, "Timed out flushing RX FIFO\n");
252
253 val = readl(regs + S3C64XX_SPI_CH_CFG);
254 val &= ~S3C64XX_SPI_CH_SW_RST;
255 writel(val, regs + S3C64XX_SPI_CH_CFG);
256
257 val = readl(regs + S3C64XX_SPI_MODE_CFG);
258 val &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
259 writel(val, regs + S3C64XX_SPI_MODE_CFG);
260 }
261
262 static void s3c64xx_spi_dmacb(void *data)
263 {
264 struct s3c64xx_spi_driver_data *sdd;
265 struct s3c64xx_spi_dma_data *dma = data;
266 unsigned long flags;
267
268 if (dma->direction == DMA_DEV_TO_MEM)
269 sdd = container_of(data,
270 struct s3c64xx_spi_driver_data, rx_dma);
271 else
272 sdd = container_of(data,
273 struct s3c64xx_spi_driver_data, tx_dma);
274
275 spin_lock_irqsave(&sdd->lock, flags);
276
277 if (dma->direction == DMA_DEV_TO_MEM) {
278 sdd->state &= ~RXBUSY;
279 if (!(sdd->state & TXBUSY))
280 complete(&sdd->xfer_completion);
281 } else {
282 sdd->state &= ~TXBUSY;
283 if (!(sdd->state & RXBUSY))
284 complete(&sdd->xfer_completion);
285 }
286
287 spin_unlock_irqrestore(&sdd->lock, flags);
288 }
289
290 #ifdef CONFIG_S3C_DMA
291 /* FIXME: remove this section once arch/arm/mach-s3c64xx uses dmaengine */
292
293 static struct s3c2410_dma_client s3c64xx_spi_dma_client = {
294 .name = "samsung-spi-dma",
295 };
296
297 static void prepare_dma(struct s3c64xx_spi_dma_data *dma,
298 unsigned len, dma_addr_t buf)
299 {
300 struct s3c64xx_spi_driver_data *sdd;
301 struct samsung_dma_prep info;
302 struct samsung_dma_config config;
303
304 if (dma->direction == DMA_DEV_TO_MEM) {
305 sdd = container_of((void *)dma,
306 struct s3c64xx_spi_driver_data, rx_dma);
307 config.direction = sdd->rx_dma.direction;
308 config.fifo = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
309 config.width = sdd->cur_bpw / 8;
310 sdd->ops->config((enum dma_ch)sdd->rx_dma.ch, &config);
311 } else {
312 sdd = container_of((void *)dma,
313 struct s3c64xx_spi_driver_data, tx_dma);
314 config.direction = sdd->tx_dma.direction;
315 config.fifo = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
316 config.width = sdd->cur_bpw / 8;
317 sdd->ops->config((enum dma_ch)sdd->tx_dma.ch, &config);
318 }
319
320 info.cap = DMA_SLAVE;
321 info.len = len;
322 info.fp = s3c64xx_spi_dmacb;
323 info.fp_param = dma;
324 info.direction = dma->direction;
325 info.buf = buf;
326
327 sdd->ops->prepare((enum dma_ch)dma->ch, &info);
328 sdd->ops->trigger((enum dma_ch)dma->ch);
329 }
330
331 static int acquire_dma(struct s3c64xx_spi_driver_data *sdd)
332 {
333 struct samsung_dma_req req;
334 struct device *dev = &sdd->pdev->dev;
335
336 sdd->ops = samsung_dma_get_ops();
337
338 req.cap = DMA_SLAVE;
339 req.client = &s3c64xx_spi_dma_client;
340
341 sdd->rx_dma.ch = (void *)sdd->ops->request(sdd->rx_dma.dmach, &req, dev, "rx");
342 sdd->tx_dma.ch = (void *)sdd->ops->request(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 pm_runtime_get_sync(&sdd->pdev->dev);
360
361 return 0;
362 }
363
364 static int s3c64xx_spi_unprepare_transfer(struct spi_master *spi)
365 {
366 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
367
368 /* Free DMA channels */
369 if (!is_polling(sdd)) {
370 sdd->ops->release((enum dma_ch)sdd->rx_dma.ch,
371 &s3c64xx_spi_dma_client);
372 sdd->ops->release((enum dma_ch)sdd->tx_dma.ch,
373 &s3c64xx_spi_dma_client);
374 }
375 pm_runtime_put(&sdd->pdev->dev);
376
377 return 0;
378 }
379
380 static void s3c64xx_spi_dma_stop(struct s3c64xx_spi_driver_data *sdd,
381 struct s3c64xx_spi_dma_data *dma)
382 {
383 sdd->ops->stop((enum dma_ch)dma->ch);
384 }
385 #else
386
387 static void prepare_dma(struct s3c64xx_spi_dma_data *dma,
388 unsigned len, dma_addr_t buf)
389 {
390 struct s3c64xx_spi_driver_data *sdd;
391 struct dma_slave_config config;
392 struct scatterlist sg;
393 struct dma_async_tx_descriptor *desc;
394
395 if (dma->direction == DMA_DEV_TO_MEM) {
396 sdd = container_of((void *)dma,
397 struct s3c64xx_spi_driver_data, rx_dma);
398 config.direction = dma->direction;
399 config.src_addr = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
400 config.src_addr_width = sdd->cur_bpw / 8;
401 config.src_maxburst = 1;
402 dmaengine_slave_config(dma->ch, &config);
403 } else {
404 sdd = container_of((void *)dma,
405 struct s3c64xx_spi_driver_data, tx_dma);
406 config.direction = dma->direction;
407 config.dst_addr = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
408 config.dst_addr_width = sdd->cur_bpw / 8;
409 config.dst_maxburst = 1;
410 dmaengine_slave_config(dma->ch, &config);
411 }
412
413 sg_init_table(&sg, 1);
414 sg_dma_len(&sg) = len;
415 sg_set_page(&sg, pfn_to_page(PFN_DOWN(buf)),
416 len, offset_in_page(buf));
417 sg_dma_address(&sg) = buf;
418
419 desc = dmaengine_prep_slave_sg(dma->ch,
420 &sg, 1, dma->direction, DMA_PREP_INTERRUPT);
421
422 desc->callback = s3c64xx_spi_dmacb;
423 desc->callback_param = dma;
424
425 dmaengine_submit(desc);
426 dma_async_issue_pending(dma->ch);
427 }
428
429 static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
430 {
431 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
432 dma_filter_fn filter = sdd->cntrlr_info->filter;
433 struct device *dev = &sdd->pdev->dev;
434 dma_cap_mask_t mask;
435 int ret;
436
437 if (is_polling(sdd))
438 return 0;
439
440 dma_cap_zero(mask);
441 dma_cap_set(DMA_SLAVE, mask);
442
443 /* Acquire DMA channels */
444 sdd->rx_dma.ch = dma_request_slave_channel_compat(mask, filter,
445 (void*)sdd->rx_dma.dmach, dev, "rx");
446 if (!sdd->rx_dma.ch) {
447 dev_err(dev, "Failed to get RX DMA channel\n");
448 ret = -EBUSY;
449 goto out;
450 }
451
452 sdd->tx_dma.ch = dma_request_slave_channel_compat(mask, filter,
453 (void*)sdd->tx_dma.dmach, dev, "tx");
454 if (!sdd->tx_dma.ch) {
455 dev_err(dev, "Failed to get TX DMA channel\n");
456 ret = -EBUSY;
457 goto out_rx;
458 }
459
460 ret = pm_runtime_get_sync(&sdd->pdev->dev);
461 if (ret < 0) {
462 dev_err(dev, "Failed to enable device: %d\n", ret);
463 goto out_tx;
464 }
465
466 return 0;
467
468 out_tx:
469 dma_release_channel(sdd->tx_dma.ch);
470 out_rx:
471 dma_release_channel(sdd->rx_dma.ch);
472 out:
473 return ret;
474 }
475
476 static int s3c64xx_spi_unprepare_transfer(struct spi_master *spi)
477 {
478 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
479
480 /* Free DMA channels */
481 if (!is_polling(sdd)) {
482 dma_release_channel(sdd->rx_dma.ch);
483 dma_release_channel(sdd->tx_dma.ch);
484 }
485
486 pm_runtime_put(&sdd->pdev->dev);
487 return 0;
488 }
489
490 static void s3c64xx_spi_dma_stop(struct s3c64xx_spi_driver_data *sdd,
491 struct s3c64xx_spi_dma_data *dma)
492 {
493 dmaengine_terminate_all(dma->ch);
494 }
495 #endif
496
497 static void enable_datapath(struct s3c64xx_spi_driver_data *sdd,
498 struct spi_device *spi,
499 struct spi_transfer *xfer, int dma_mode)
500 {
501 void __iomem *regs = sdd->regs;
502 u32 modecfg, chcfg;
503
504 modecfg = readl(regs + S3C64XX_SPI_MODE_CFG);
505 modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
506
507 chcfg = readl(regs + S3C64XX_SPI_CH_CFG);
508 chcfg &= ~S3C64XX_SPI_CH_TXCH_ON;
509
510 if (dma_mode) {
511 chcfg &= ~S3C64XX_SPI_CH_RXCH_ON;
512 } else {
513 /* Always shift in data in FIFO, even if xfer is Tx only,
514 * this helps setting PCKT_CNT value for generating clocks
515 * as exactly needed.
516 */
517 chcfg |= S3C64XX_SPI_CH_RXCH_ON;
518 writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
519 | S3C64XX_SPI_PACKET_CNT_EN,
520 regs + S3C64XX_SPI_PACKET_CNT);
521 }
522
523 if (xfer->tx_buf != NULL) {
524 sdd->state |= TXBUSY;
525 chcfg |= S3C64XX_SPI_CH_TXCH_ON;
526 if (dma_mode) {
527 modecfg |= S3C64XX_SPI_MODE_TXDMA_ON;
528 prepare_dma(&sdd->tx_dma, xfer->len, xfer->tx_dma);
529 } else {
530 switch (sdd->cur_bpw) {
531 case 32:
532 iowrite32_rep(regs + S3C64XX_SPI_TX_DATA,
533 xfer->tx_buf, xfer->len / 4);
534 break;
535 case 16:
536 iowrite16_rep(regs + S3C64XX_SPI_TX_DATA,
537 xfer->tx_buf, xfer->len / 2);
538 break;
539 default:
540 iowrite8_rep(regs + S3C64XX_SPI_TX_DATA,
541 xfer->tx_buf, xfer->len);
542 break;
543 }
544 }
545 }
546
547 if (xfer->rx_buf != NULL) {
548 sdd->state |= RXBUSY;
549
550 if (sdd->port_conf->high_speed && sdd->cur_speed >= 30000000UL
551 && !(sdd->cur_mode & SPI_CPHA))
552 chcfg |= S3C64XX_SPI_CH_HS_EN;
553
554 if (dma_mode) {
555 modecfg |= S3C64XX_SPI_MODE_RXDMA_ON;
556 chcfg |= S3C64XX_SPI_CH_RXCH_ON;
557 writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
558 | S3C64XX_SPI_PACKET_CNT_EN,
559 regs + S3C64XX_SPI_PACKET_CNT);
560 prepare_dma(&sdd->rx_dma, xfer->len, xfer->rx_dma);
561 }
562 }
563
564 writel(modecfg, regs + S3C64XX_SPI_MODE_CFG);
565 writel(chcfg, regs + S3C64XX_SPI_CH_CFG);
566 }
567
568 static inline void enable_cs(struct s3c64xx_spi_driver_data *sdd,
569 struct spi_device *spi)
570 {
571 struct s3c64xx_spi_csinfo *cs;
572
573 if (sdd->tgl_spi != NULL) { /* If last device toggled after mssg */
574 if (sdd->tgl_spi != spi) { /* if last mssg on diff device */
575 /* Deselect the last toggled device */
576 cs = sdd->tgl_spi->controller_data;
577 if (sdd->cs_gpio)
578 gpio_set_value(cs->line,
579 spi->mode & SPI_CS_HIGH ? 0 : 1);
580 }
581 sdd->tgl_spi = NULL;
582 }
583
584 cs = spi->controller_data;
585 if (sdd->cs_gpio)
586 gpio_set_value(cs->line, spi->mode & SPI_CS_HIGH ? 1 : 0);
587
588 /* Start the signals */
589 writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
590 }
591
592 static u32 s3c64xx_spi_wait_for_timeout(struct s3c64xx_spi_driver_data *sdd,
593 int timeout_ms)
594 {
595 void __iomem *regs = sdd->regs;
596 unsigned long val = 1;
597 u32 status;
598
599 /* max fifo depth available */
600 u32 max_fifo = (FIFO_LVL_MASK(sdd) >> 1) + 1;
601
602 if (timeout_ms)
603 val = msecs_to_loops(timeout_ms);
604
605 do {
606 status = readl(regs + S3C64XX_SPI_STATUS);
607 } while (RX_FIFO_LVL(status, sdd) < max_fifo && --val);
608
609 /* return the actual received data length */
610 return RX_FIFO_LVL(status, sdd);
611 }
612
613 static int wait_for_xfer(struct s3c64xx_spi_driver_data *sdd,
614 struct spi_transfer *xfer, int dma_mode)
615 {
616 void __iomem *regs = sdd->regs;
617 unsigned long val;
618 int ms;
619
620 /* millisecs to xfer 'len' bytes @ 'cur_speed' */
621 ms = xfer->len * 8 * 1000 / sdd->cur_speed;
622 ms += 10; /* some tolerance */
623
624 if (dma_mode) {
625 val = msecs_to_jiffies(ms) + 10;
626 val = wait_for_completion_timeout(&sdd->xfer_completion, val);
627 } else {
628 u32 status;
629 val = msecs_to_loops(ms);
630 do {
631 status = readl(regs + S3C64XX_SPI_STATUS);
632 } while (RX_FIFO_LVL(status, sdd) < xfer->len && --val);
633 }
634
635 if (dma_mode) {
636 u32 status;
637
638 /*
639 * If the previous xfer was completed within timeout, then
640 * proceed further else return -EIO.
641 * DmaTx returns after simply writing data in the FIFO,
642 * w/o waiting for real transmission on the bus to finish.
643 * DmaRx returns only after Dma read data from FIFO which
644 * needs bus transmission to finish, so we don't worry if
645 * Xfer involved Rx(with or without Tx).
646 */
647 if (val && !xfer->rx_buf) {
648 val = msecs_to_loops(10);
649 status = readl(regs + S3C64XX_SPI_STATUS);
650 while ((TX_FIFO_LVL(status, sdd)
651 || !S3C64XX_SPI_ST_TX_DONE(status, sdd))
652 && --val) {
653 cpu_relax();
654 status = readl(regs + S3C64XX_SPI_STATUS);
655 }
656
657 }
658
659 /* If timed out while checking rx/tx status return error */
660 if (!val)
661 return -EIO;
662 } else {
663 int loops;
664 u32 cpy_len;
665 u8 *buf;
666
667 /* If it was only Tx */
668 if (!xfer->rx_buf) {
669 sdd->state &= ~TXBUSY;
670 return 0;
671 }
672
673 /*
674 * If the receive length is bigger than the controller fifo
675 * size, calculate the loops and read the fifo as many times.
676 * loops = length / max fifo size (calculated by using the
677 * fifo mask).
678 * For any size less than the fifo size the below code is
679 * executed atleast once.
680 */
681 loops = xfer->len / ((FIFO_LVL_MASK(sdd) >> 1) + 1);
682 buf = xfer->rx_buf;
683 do {
684 /* wait for data to be received in the fifo */
685 cpy_len = s3c64xx_spi_wait_for_timeout(sdd,
686 (loops ? ms : 0));
687
688 switch (sdd->cur_bpw) {
689 case 32:
690 ioread32_rep(regs + S3C64XX_SPI_RX_DATA,
691 buf, cpy_len / 4);
692 break;
693 case 16:
694 ioread16_rep(regs + S3C64XX_SPI_RX_DATA,
695 buf, cpy_len / 2);
696 break;
697 default:
698 ioread8_rep(regs + S3C64XX_SPI_RX_DATA,
699 buf, cpy_len);
700 break;
701 }
702
703 buf = buf + cpy_len;
704 } while (loops--);
705 sdd->state &= ~RXBUSY;
706 }
707
708 return 0;
709 }
710
711 static inline void disable_cs(struct s3c64xx_spi_driver_data *sdd,
712 struct spi_device *spi)
713 {
714 struct s3c64xx_spi_csinfo *cs = spi->controller_data;
715
716 if (sdd->tgl_spi == spi)
717 sdd->tgl_spi = NULL;
718
719 if (sdd->cs_gpio)
720 gpio_set_value(cs->line, spi->mode & SPI_CS_HIGH ? 0 : 1);
721
722 /* Quiese the signals */
723 writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
724 }
725
726 static void s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
727 {
728 void __iomem *regs = sdd->regs;
729 u32 val;
730
731 /* Disable Clock */
732 if (sdd->port_conf->clk_from_cmu) {
733 clk_disable_unprepare(sdd->src_clk);
734 } else {
735 val = readl(regs + S3C64XX_SPI_CLK_CFG);
736 val &= ~S3C64XX_SPI_ENCLK_ENABLE;
737 writel(val, regs + S3C64XX_SPI_CLK_CFG);
738 }
739
740 /* Set Polarity and Phase */
741 val = readl(regs + S3C64XX_SPI_CH_CFG);
742 val &= ~(S3C64XX_SPI_CH_SLAVE |
743 S3C64XX_SPI_CPOL_L |
744 S3C64XX_SPI_CPHA_B);
745
746 if (sdd->cur_mode & SPI_CPOL)
747 val |= S3C64XX_SPI_CPOL_L;
748
749 if (sdd->cur_mode & SPI_CPHA)
750 val |= S3C64XX_SPI_CPHA_B;
751
752 writel(val, regs + S3C64XX_SPI_CH_CFG);
753
754 /* Set Channel & DMA Mode */
755 val = readl(regs + S3C64XX_SPI_MODE_CFG);
756 val &= ~(S3C64XX_SPI_MODE_BUS_TSZ_MASK
757 | S3C64XX_SPI_MODE_CH_TSZ_MASK);
758
759 switch (sdd->cur_bpw) {
760 case 32:
761 val |= S3C64XX_SPI_MODE_BUS_TSZ_WORD;
762 val |= S3C64XX_SPI_MODE_CH_TSZ_WORD;
763 break;
764 case 16:
765 val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD;
766 val |= S3C64XX_SPI_MODE_CH_TSZ_HALFWORD;
767 break;
768 default:
769 val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE;
770 val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE;
771 break;
772 }
773
774 writel(val, regs + S3C64XX_SPI_MODE_CFG);
775
776 if (sdd->port_conf->clk_from_cmu) {
777 /* Configure Clock */
778 /* There is half-multiplier before the SPI */
779 clk_set_rate(sdd->src_clk, sdd->cur_speed * 2);
780 /* Enable Clock */
781 clk_prepare_enable(sdd->src_clk);
782 } else {
783 /* Configure Clock */
784 val = readl(regs + S3C64XX_SPI_CLK_CFG);
785 val &= ~S3C64XX_SPI_PSR_MASK;
786 val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / 2 - 1)
787 & S3C64XX_SPI_PSR_MASK);
788 writel(val, regs + S3C64XX_SPI_CLK_CFG);
789
790 /* Enable Clock */
791 val = readl(regs + S3C64XX_SPI_CLK_CFG);
792 val |= S3C64XX_SPI_ENCLK_ENABLE;
793 writel(val, regs + S3C64XX_SPI_CLK_CFG);
794 }
795 }
796
797 #define XFER_DMAADDR_INVALID DMA_BIT_MASK(32)
798
799 static int s3c64xx_spi_map_mssg(struct s3c64xx_spi_driver_data *sdd,
800 struct spi_message *msg)
801 {
802 struct device *dev = &sdd->pdev->dev;
803 struct spi_transfer *xfer;
804
805 if (is_polling(sdd) || msg->is_dma_mapped)
806 return 0;
807
808 /* First mark all xfer unmapped */
809 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
810 xfer->rx_dma = XFER_DMAADDR_INVALID;
811 xfer->tx_dma = XFER_DMAADDR_INVALID;
812 }
813
814 /* Map until end or first fail */
815 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
816
817 if (xfer->len <= ((FIFO_LVL_MASK(sdd) >> 1) + 1))
818 continue;
819
820 if (xfer->tx_buf != NULL) {
821 xfer->tx_dma = dma_map_single(dev,
822 (void *)xfer->tx_buf, xfer->len,
823 DMA_TO_DEVICE);
824 if (dma_mapping_error(dev, xfer->tx_dma)) {
825 dev_err(dev, "dma_map_single Tx failed\n");
826 xfer->tx_dma = XFER_DMAADDR_INVALID;
827 return -ENOMEM;
828 }
829 }
830
831 if (xfer->rx_buf != NULL) {
832 xfer->rx_dma = dma_map_single(dev, xfer->rx_buf,
833 xfer->len, DMA_FROM_DEVICE);
834 if (dma_mapping_error(dev, xfer->rx_dma)) {
835 dev_err(dev, "dma_map_single Rx failed\n");
836 dma_unmap_single(dev, xfer->tx_dma,
837 xfer->len, DMA_TO_DEVICE);
838 xfer->tx_dma = XFER_DMAADDR_INVALID;
839 xfer->rx_dma = XFER_DMAADDR_INVALID;
840 return -ENOMEM;
841 }
842 }
843 }
844
845 return 0;
846 }
847
848 static void s3c64xx_spi_unmap_mssg(struct s3c64xx_spi_driver_data *sdd,
849 struct spi_message *msg)
850 {
851 struct device *dev = &sdd->pdev->dev;
852 struct spi_transfer *xfer;
853
854 if (is_polling(sdd) || msg->is_dma_mapped)
855 return;
856
857 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
858
859 if (xfer->len <= ((FIFO_LVL_MASK(sdd) >> 1) + 1))
860 continue;
861
862 if (xfer->rx_buf != NULL
863 && xfer->rx_dma != XFER_DMAADDR_INVALID)
864 dma_unmap_single(dev, xfer->rx_dma,
865 xfer->len, DMA_FROM_DEVICE);
866
867 if (xfer->tx_buf != NULL
868 && xfer->tx_dma != XFER_DMAADDR_INVALID)
869 dma_unmap_single(dev, xfer->tx_dma,
870 xfer->len, DMA_TO_DEVICE);
871 }
872 }
873
874 static int s3c64xx_spi_transfer_one_message(struct spi_master *master,
875 struct spi_message *msg)
876 {
877 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
878 struct spi_device *spi = msg->spi;
879 struct s3c64xx_spi_csinfo *cs = spi->controller_data;
880 struct spi_transfer *xfer;
881 int status = 0, cs_toggle = 0;
882 u32 speed;
883 u8 bpw;
884
885 /* If Master's(controller) state differs from that needed by Slave */
886 if (sdd->cur_speed != spi->max_speed_hz
887 || sdd->cur_mode != spi->mode
888 || sdd->cur_bpw != spi->bits_per_word) {
889 sdd->cur_bpw = spi->bits_per_word;
890 sdd->cur_speed = spi->max_speed_hz;
891 sdd->cur_mode = spi->mode;
892 s3c64xx_spi_config(sdd);
893 }
894
895 /* Map all the transfers if needed */
896 if (s3c64xx_spi_map_mssg(sdd, msg)) {
897 dev_err(&spi->dev,
898 "Xfer: Unable to map message buffers!\n");
899 status = -ENOMEM;
900 goto out;
901 }
902
903 /* Configure feedback delay */
904 writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK);
905
906 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
907
908 unsigned long flags;
909 int use_dma;
910
911 INIT_COMPLETION(sdd->xfer_completion);
912
913 /* Only BPW and Speed may change across transfers */
914 bpw = xfer->bits_per_word;
915 speed = xfer->speed_hz ? : spi->max_speed_hz;
916
917 if (xfer->len % (bpw / 8)) {
918 dev_err(&spi->dev,
919 "Xfer length(%u) not a multiple of word size(%u)\n",
920 xfer->len, bpw / 8);
921 status = -EIO;
922 goto out;
923 }
924
925 if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) {
926 sdd->cur_bpw = bpw;
927 sdd->cur_speed = speed;
928 s3c64xx_spi_config(sdd);
929 }
930
931 /* Polling method for xfers not bigger than FIFO capacity */
932 use_dma = 0;
933 if (!is_polling(sdd) &&
934 (sdd->rx_dma.ch && sdd->tx_dma.ch &&
935 (xfer->len > ((FIFO_LVL_MASK(sdd) >> 1) + 1))))
936 use_dma = 1;
937
938 spin_lock_irqsave(&sdd->lock, flags);
939
940 /* Pending only which is to be done */
941 sdd->state &= ~RXBUSY;
942 sdd->state &= ~TXBUSY;
943
944 enable_datapath(sdd, spi, xfer, use_dma);
945
946 /* Slave Select */
947 enable_cs(sdd, spi);
948
949 spin_unlock_irqrestore(&sdd->lock, flags);
950
951 status = wait_for_xfer(sdd, xfer, use_dma);
952
953 if (status) {
954 dev_err(&spi->dev, "I/O Error: rx-%d tx-%d res:rx-%c tx-%c len-%d\n",
955 xfer->rx_buf ? 1 : 0, xfer->tx_buf ? 1 : 0,
956 (sdd->state & RXBUSY) ? 'f' : 'p',
957 (sdd->state & TXBUSY) ? 'f' : 'p',
958 xfer->len);
959
960 if (use_dma) {
961 if (xfer->tx_buf != NULL
962 && (sdd->state & TXBUSY))
963 s3c64xx_spi_dma_stop(sdd, &sdd->tx_dma);
964 if (xfer->rx_buf != NULL
965 && (sdd->state & RXBUSY))
966 s3c64xx_spi_dma_stop(sdd, &sdd->rx_dma);
967 }
968
969 goto out;
970 }
971
972 if (xfer->delay_usecs)
973 udelay(xfer->delay_usecs);
974
975 if (xfer->cs_change) {
976 /* Hint that the next mssg is gonna be
977 for the same device */
978 if (list_is_last(&xfer->transfer_list,
979 &msg->transfers))
980 cs_toggle = 1;
981 }
982
983 msg->actual_length += xfer->len;
984
985 flush_fifo(sdd);
986 }
987
988 out:
989 if (!cs_toggle || status)
990 disable_cs(sdd, spi);
991 else
992 sdd->tgl_spi = spi;
993
994 s3c64xx_spi_unmap_mssg(sdd, msg);
995
996 msg->status = status;
997
998 spi_finalize_current_message(master);
999
1000 return 0;
1001 }
1002
1003 static struct s3c64xx_spi_csinfo *s3c64xx_get_slave_ctrldata(
1004 struct spi_device *spi)
1005 {
1006 struct s3c64xx_spi_csinfo *cs;
1007 struct device_node *slave_np, *data_np = NULL;
1008 struct s3c64xx_spi_driver_data *sdd;
1009 u32 fb_delay = 0;
1010
1011 sdd = spi_master_get_devdata(spi->master);
1012 slave_np = spi->dev.of_node;
1013 if (!slave_np) {
1014 dev_err(&spi->dev, "device node not found\n");
1015 return ERR_PTR(-EINVAL);
1016 }
1017
1018 data_np = of_get_child_by_name(slave_np, "controller-data");
1019 if (!data_np) {
1020 dev_err(&spi->dev, "child node 'controller-data' not found\n");
1021 return ERR_PTR(-EINVAL);
1022 }
1023
1024 cs = kzalloc(sizeof(*cs), GFP_KERNEL);
1025 if (!cs) {
1026 dev_err(&spi->dev, "could not allocate memory for controller data\n");
1027 of_node_put(data_np);
1028 return ERR_PTR(-ENOMEM);
1029 }
1030
1031 /* The CS line is asserted/deasserted by the gpio pin */
1032 if (sdd->cs_gpio)
1033 cs->line = of_get_named_gpio(data_np, "cs-gpio", 0);
1034
1035 if (!gpio_is_valid(cs->line)) {
1036 dev_err(&spi->dev, "chip select gpio is not specified or invalid\n");
1037 kfree(cs);
1038 of_node_put(data_np);
1039 return ERR_PTR(-EINVAL);
1040 }
1041
1042 of_property_read_u32(data_np, "samsung,spi-feedback-delay", &fb_delay);
1043 cs->fb_delay = fb_delay;
1044 of_node_put(data_np);
1045 return cs;
1046 }
1047
1048 /*
1049 * Here we only check the validity of requested configuration
1050 * and save the configuration in a local data-structure.
1051 * The controller is actually configured only just before we
1052 * get a message to transfer.
1053 */
1054 static int s3c64xx_spi_setup(struct spi_device *spi)
1055 {
1056 struct s3c64xx_spi_csinfo *cs = spi->controller_data;
1057 struct s3c64xx_spi_driver_data *sdd;
1058 struct s3c64xx_spi_info *sci;
1059 struct spi_message *msg;
1060 unsigned long flags;
1061 int err;
1062
1063 sdd = spi_master_get_devdata(spi->master);
1064 if (!cs && spi->dev.of_node) {
1065 cs = s3c64xx_get_slave_ctrldata(spi);
1066 spi->controller_data = cs;
1067 }
1068
1069 if (IS_ERR_OR_NULL(cs)) {
1070 dev_err(&spi->dev, "No CS for SPI(%d)\n", spi->chip_select);
1071 return -ENODEV;
1072 }
1073
1074 /* Request gpio only if cs line is asserted by gpio pins */
1075 if (sdd->cs_gpio) {
1076 err = gpio_request_one(cs->line, GPIOF_OUT_INIT_HIGH,
1077 dev_name(&spi->dev));
1078 if (err) {
1079 dev_err(&spi->dev,
1080 "Failed to get /CS gpio [%d]: %d\n",
1081 cs->line, err);
1082 goto err_gpio_req;
1083 }
1084 }
1085
1086 if (!spi_get_ctldata(spi))
1087 spi_set_ctldata(spi, cs);
1088
1089 sci = sdd->cntrlr_info;
1090
1091 spin_lock_irqsave(&sdd->lock, flags);
1092
1093 list_for_each_entry(msg, &sdd->queue, queue) {
1094 /* Is some mssg is already queued for this device */
1095 if (msg->spi == spi) {
1096 dev_err(&spi->dev,
1097 "setup: attempt while mssg in queue!\n");
1098 spin_unlock_irqrestore(&sdd->lock, flags);
1099 err = -EBUSY;
1100 goto err_msgq;
1101 }
1102 }
1103
1104 spin_unlock_irqrestore(&sdd->lock, flags);
1105
1106 pm_runtime_get_sync(&sdd->pdev->dev);
1107
1108 /* Check if we can provide the requested rate */
1109 if (!sdd->port_conf->clk_from_cmu) {
1110 u32 psr, speed;
1111
1112 /* Max possible */
1113 speed = clk_get_rate(sdd->src_clk) / 2 / (0 + 1);
1114
1115 if (spi->max_speed_hz > speed)
1116 spi->max_speed_hz = speed;
1117
1118 psr = clk_get_rate(sdd->src_clk) / 2 / spi->max_speed_hz - 1;
1119 psr &= S3C64XX_SPI_PSR_MASK;
1120 if (psr == S3C64XX_SPI_PSR_MASK)
1121 psr--;
1122
1123 speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
1124 if (spi->max_speed_hz < speed) {
1125 if (psr+1 < S3C64XX_SPI_PSR_MASK) {
1126 psr++;
1127 } else {
1128 err = -EINVAL;
1129 goto setup_exit;
1130 }
1131 }
1132
1133 speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
1134 if (spi->max_speed_hz >= speed) {
1135 spi->max_speed_hz = speed;
1136 } else {
1137 dev_err(&spi->dev, "Can't set %dHz transfer speed\n",
1138 spi->max_speed_hz);
1139 err = -EINVAL;
1140 goto setup_exit;
1141 }
1142 }
1143
1144 pm_runtime_put(&sdd->pdev->dev);
1145 disable_cs(sdd, spi);
1146 return 0;
1147
1148 setup_exit:
1149 /* setup() returns with device de-selected */
1150 disable_cs(sdd, spi);
1151
1152 err_msgq:
1153 gpio_free(cs->line);
1154 spi_set_ctldata(spi, NULL);
1155
1156 err_gpio_req:
1157 if (spi->dev.of_node)
1158 kfree(cs);
1159
1160 return err;
1161 }
1162
1163 static void s3c64xx_spi_cleanup(struct spi_device *spi)
1164 {
1165 struct s3c64xx_spi_csinfo *cs = spi_get_ctldata(spi);
1166 struct s3c64xx_spi_driver_data *sdd;
1167
1168 sdd = spi_master_get_devdata(spi->master);
1169 if (cs && sdd->cs_gpio) {
1170 gpio_free(cs->line);
1171 if (spi->dev.of_node)
1172 kfree(cs);
1173 }
1174 spi_set_ctldata(spi, NULL);
1175 }
1176
1177 static irqreturn_t s3c64xx_spi_irq(int irq, void *data)
1178 {
1179 struct s3c64xx_spi_driver_data *sdd = data;
1180 struct spi_master *spi = sdd->master;
1181 unsigned int val, clr = 0;
1182
1183 val = readl(sdd->regs + S3C64XX_SPI_STATUS);
1184
1185 if (val & S3C64XX_SPI_ST_RX_OVERRUN_ERR) {
1186 clr = S3C64XX_SPI_PND_RX_OVERRUN_CLR;
1187 dev_err(&spi->dev, "RX overrun\n");
1188 }
1189 if (val & S3C64XX_SPI_ST_RX_UNDERRUN_ERR) {
1190 clr |= S3C64XX_SPI_PND_RX_UNDERRUN_CLR;
1191 dev_err(&spi->dev, "RX underrun\n");
1192 }
1193 if (val & S3C64XX_SPI_ST_TX_OVERRUN_ERR) {
1194 clr |= S3C64XX_SPI_PND_TX_OVERRUN_CLR;
1195 dev_err(&spi->dev, "TX overrun\n");
1196 }
1197 if (val & S3C64XX_SPI_ST_TX_UNDERRUN_ERR) {
1198 clr |= S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
1199 dev_err(&spi->dev, "TX underrun\n");
1200 }
1201
1202 /* Clear the pending irq by setting and then clearing it */
1203 writel(clr, sdd->regs + S3C64XX_SPI_PENDING_CLR);
1204 writel(0, sdd->regs + S3C64XX_SPI_PENDING_CLR);
1205
1206 return IRQ_HANDLED;
1207 }
1208
1209 static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd, int channel)
1210 {
1211 struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1212 void __iomem *regs = sdd->regs;
1213 unsigned int val;
1214
1215 sdd->cur_speed = 0;
1216
1217 writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
1218
1219 /* Disable Interrupts - we use Polling if not DMA mode */
1220 writel(0, regs + S3C64XX_SPI_INT_EN);
1221
1222 if (!sdd->port_conf->clk_from_cmu)
1223 writel(sci->src_clk_nr << S3C64XX_SPI_CLKSEL_SRCSHFT,
1224 regs + S3C64XX_SPI_CLK_CFG);
1225 writel(0, regs + S3C64XX_SPI_MODE_CFG);
1226 writel(0, regs + S3C64XX_SPI_PACKET_CNT);
1227
1228 /* Clear any irq pending bits, should set and clear the bits */
1229 val = S3C64XX_SPI_PND_RX_OVERRUN_CLR |
1230 S3C64XX_SPI_PND_RX_UNDERRUN_CLR |
1231 S3C64XX_SPI_PND_TX_OVERRUN_CLR |
1232 S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
1233 writel(val, regs + S3C64XX_SPI_PENDING_CLR);
1234 writel(0, regs + S3C64XX_SPI_PENDING_CLR);
1235
1236 writel(0, regs + S3C64XX_SPI_SWAP_CFG);
1237
1238 val = readl(regs + S3C64XX_SPI_MODE_CFG);
1239 val &= ~S3C64XX_SPI_MODE_4BURST;
1240 val &= ~(S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
1241 val |= (S3C64XX_SPI_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
1242 writel(val, regs + S3C64XX_SPI_MODE_CFG);
1243
1244 flush_fifo(sdd);
1245 }
1246
1247 #ifdef CONFIG_OF
1248 static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
1249 {
1250 struct s3c64xx_spi_info *sci;
1251 u32 temp;
1252
1253 sci = devm_kzalloc(dev, sizeof(*sci), GFP_KERNEL);
1254 if (!sci) {
1255 dev_err(dev, "memory allocation for spi_info failed\n");
1256 return ERR_PTR(-ENOMEM);
1257 }
1258
1259 if (of_property_read_u32(dev->of_node, "samsung,spi-src-clk", &temp)) {
1260 dev_warn(dev, "spi bus clock parent not specified, using clock at index 0 as parent\n");
1261 sci->src_clk_nr = 0;
1262 } else {
1263 sci->src_clk_nr = temp;
1264 }
1265
1266 if (of_property_read_u32(dev->of_node, "num-cs", &temp)) {
1267 dev_warn(dev, "number of chip select lines not specified, assuming 1 chip select line\n");
1268 sci->num_cs = 1;
1269 } else {
1270 sci->num_cs = temp;
1271 }
1272
1273 return sci;
1274 }
1275 #else
1276 static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
1277 {
1278 return dev->platform_data;
1279 }
1280 #endif
1281
1282 static const struct of_device_id s3c64xx_spi_dt_match[];
1283
1284 static inline struct s3c64xx_spi_port_config *s3c64xx_spi_get_port_config(
1285 struct platform_device *pdev)
1286 {
1287 #ifdef CONFIG_OF
1288 if (pdev->dev.of_node) {
1289 const struct of_device_id *match;
1290 match = of_match_node(s3c64xx_spi_dt_match, pdev->dev.of_node);
1291 return (struct s3c64xx_spi_port_config *)match->data;
1292 }
1293 #endif
1294 return (struct s3c64xx_spi_port_config *)
1295 platform_get_device_id(pdev)->driver_data;
1296 }
1297
1298 static int s3c64xx_spi_probe(struct platform_device *pdev)
1299 {
1300 struct resource *mem_res;
1301 struct resource *res;
1302 struct s3c64xx_spi_driver_data *sdd;
1303 struct s3c64xx_spi_info *sci = pdev->dev.platform_data;
1304 struct spi_master *master;
1305 int ret, irq;
1306 char clk_name[16];
1307
1308 if (!sci && pdev->dev.of_node) {
1309 sci = s3c64xx_spi_parse_dt(&pdev->dev);
1310 if (IS_ERR(sci))
1311 return PTR_ERR(sci);
1312 }
1313
1314 if (!sci) {
1315 dev_err(&pdev->dev, "platform_data missing!\n");
1316 return -ENODEV;
1317 }
1318
1319 mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1320 if (mem_res == NULL) {
1321 dev_err(&pdev->dev, "Unable to get SPI MEM resource\n");
1322 return -ENXIO;
1323 }
1324
1325 irq = platform_get_irq(pdev, 0);
1326 if (irq < 0) {
1327 dev_warn(&pdev->dev, "Failed to get IRQ: %d\n", irq);
1328 return irq;
1329 }
1330
1331 master = spi_alloc_master(&pdev->dev,
1332 sizeof(struct s3c64xx_spi_driver_data));
1333 if (master == NULL) {
1334 dev_err(&pdev->dev, "Unable to allocate SPI Master\n");
1335 return -ENOMEM;
1336 }
1337
1338 platform_set_drvdata(pdev, master);
1339
1340 sdd = spi_master_get_devdata(master);
1341 sdd->port_conf = s3c64xx_spi_get_port_config(pdev);
1342 sdd->master = master;
1343 sdd->cntrlr_info = sci;
1344 sdd->pdev = pdev;
1345 sdd->sfr_start = mem_res->start;
1346 sdd->cs_gpio = true;
1347 if (pdev->dev.of_node) {
1348 if (!of_find_property(pdev->dev.of_node, "cs-gpio", NULL))
1349 sdd->cs_gpio = false;
1350
1351 ret = of_alias_get_id(pdev->dev.of_node, "spi");
1352 if (ret < 0) {
1353 dev_err(&pdev->dev, "failed to get alias id, errno %d\n",
1354 ret);
1355 goto err0;
1356 }
1357 sdd->port_id = ret;
1358 } else {
1359 sdd->port_id = pdev->id;
1360 }
1361
1362 sdd->cur_bpw = 8;
1363
1364 if (!sdd->pdev->dev.of_node) {
1365 res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
1366 if (!res) {
1367 dev_warn(&pdev->dev, "Unable to get SPI tx dma "
1368 "resource. Switching to poll mode\n");
1369 sdd->port_conf->quirks = S3C64XX_SPI_QUIRK_POLL;
1370 } else
1371 sdd->tx_dma.dmach = res->start;
1372
1373 res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
1374 if (!res) {
1375 dev_warn(&pdev->dev, "Unable to get SPI rx dma "
1376 "resource. Switching to poll mode\n");
1377 sdd->port_conf->quirks = S3C64XX_SPI_QUIRK_POLL;
1378 } else
1379 sdd->rx_dma.dmach = res->start;
1380 }
1381
1382 sdd->tx_dma.direction = DMA_MEM_TO_DEV;
1383 sdd->rx_dma.direction = DMA_DEV_TO_MEM;
1384
1385 master->dev.of_node = pdev->dev.of_node;
1386 master->bus_num = sdd->port_id;
1387 master->setup = s3c64xx_spi_setup;
1388 master->cleanup = s3c64xx_spi_cleanup;
1389 master->prepare_transfer_hardware = s3c64xx_spi_prepare_transfer;
1390 master->transfer_one_message = s3c64xx_spi_transfer_one_message;
1391 master->unprepare_transfer_hardware = s3c64xx_spi_unprepare_transfer;
1392 master->num_chipselect = sci->num_cs;
1393 master->dma_alignment = 8;
1394 master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) |
1395 SPI_BPW_MASK(8);
1396 /* the spi->mode bits understood by this driver: */
1397 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1398
1399 sdd->regs = devm_ioremap_resource(&pdev->dev, mem_res);
1400 if (IS_ERR(sdd->regs)) {
1401 ret = PTR_ERR(sdd->regs);
1402 goto err0;
1403 }
1404
1405 if (sci->cfg_gpio && sci->cfg_gpio()) {
1406 dev_err(&pdev->dev, "Unable to config gpio\n");
1407 ret = -EBUSY;
1408 goto err0;
1409 }
1410
1411 /* Setup clocks */
1412 sdd->clk = devm_clk_get(&pdev->dev, "spi");
1413 if (IS_ERR(sdd->clk)) {
1414 dev_err(&pdev->dev, "Unable to acquire clock 'spi'\n");
1415 ret = PTR_ERR(sdd->clk);
1416 goto err0;
1417 }
1418
1419 if (clk_prepare_enable(sdd->clk)) {
1420 dev_err(&pdev->dev, "Couldn't enable clock 'spi'\n");
1421 ret = -EBUSY;
1422 goto err0;
1423 }
1424
1425 sprintf(clk_name, "spi_busclk%d", sci->src_clk_nr);
1426 sdd->src_clk = devm_clk_get(&pdev->dev, clk_name);
1427 if (IS_ERR(sdd->src_clk)) {
1428 dev_err(&pdev->dev,
1429 "Unable to acquire clock '%s'\n", clk_name);
1430 ret = PTR_ERR(sdd->src_clk);
1431 goto err2;
1432 }
1433
1434 if (clk_prepare_enable(sdd->src_clk)) {
1435 dev_err(&pdev->dev, "Couldn't enable clock '%s'\n", clk_name);
1436 ret = -EBUSY;
1437 goto err2;
1438 }
1439
1440 /* Setup Deufult Mode */
1441 s3c64xx_spi_hwinit(sdd, sdd->port_id);
1442
1443 spin_lock_init(&sdd->lock);
1444 init_completion(&sdd->xfer_completion);
1445 INIT_LIST_HEAD(&sdd->queue);
1446
1447 ret = devm_request_irq(&pdev->dev, irq, s3c64xx_spi_irq, 0,
1448 "spi-s3c64xx", sdd);
1449 if (ret != 0) {
1450 dev_err(&pdev->dev, "Failed to request IRQ %d: %d\n",
1451 irq, ret);
1452 goto err3;
1453 }
1454
1455 writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
1456 S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
1457 sdd->regs + S3C64XX_SPI_INT_EN);
1458
1459 if (spi_register_master(master)) {
1460 dev_err(&pdev->dev, "cannot register SPI master\n");
1461 ret = -EBUSY;
1462 goto err3;
1463 }
1464
1465 dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d with %d Slaves attached\n",
1466 sdd->port_id, master->num_chipselect);
1467 dev_dbg(&pdev->dev, "\tIOmem=[0x%x-0x%x]\tDMA=[Rx-%d, Tx-%d]\n",
1468 mem_res->end, mem_res->start,
1469 sdd->rx_dma.dmach, sdd->tx_dma.dmach);
1470
1471 pm_runtime_enable(&pdev->dev);
1472
1473 return 0;
1474
1475 err3:
1476 clk_disable_unprepare(sdd->src_clk);
1477 err2:
1478 clk_disable_unprepare(sdd->clk);
1479 err0:
1480 spi_master_put(master);
1481
1482 return ret;
1483 }
1484
1485 static int s3c64xx_spi_remove(struct platform_device *pdev)
1486 {
1487 struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
1488 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1489
1490 pm_runtime_disable(&pdev->dev);
1491
1492 spi_unregister_master(master);
1493
1494 writel(0, sdd->regs + S3C64XX_SPI_INT_EN);
1495
1496 clk_disable_unprepare(sdd->src_clk);
1497
1498 clk_disable_unprepare(sdd->clk);
1499
1500 spi_master_put(master);
1501
1502 return 0;
1503 }
1504
1505 #ifdef CONFIG_PM_SLEEP
1506 static int s3c64xx_spi_suspend(struct device *dev)
1507 {
1508 struct spi_master *master = dev_get_drvdata(dev);
1509 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1510
1511 spi_master_suspend(master);
1512
1513 /* Disable the clock */
1514 clk_disable_unprepare(sdd->src_clk);
1515 clk_disable_unprepare(sdd->clk);
1516
1517 sdd->cur_speed = 0; /* Output Clock is stopped */
1518
1519 return 0;
1520 }
1521
1522 static int s3c64xx_spi_resume(struct device *dev)
1523 {
1524 struct spi_master *master = dev_get_drvdata(dev);
1525 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1526 struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1527
1528 if (sci->cfg_gpio)
1529 sci->cfg_gpio();
1530
1531 /* Enable the clock */
1532 clk_prepare_enable(sdd->src_clk);
1533 clk_prepare_enable(sdd->clk);
1534
1535 s3c64xx_spi_hwinit(sdd, sdd->port_id);
1536
1537 spi_master_resume(master);
1538
1539 return 0;
1540 }
1541 #endif /* CONFIG_PM_SLEEP */
1542
1543 #ifdef CONFIG_PM_RUNTIME
1544 static int s3c64xx_spi_runtime_suspend(struct device *dev)
1545 {
1546 struct spi_master *master = dev_get_drvdata(dev);
1547 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1548
1549 clk_disable_unprepare(sdd->clk);
1550 clk_disable_unprepare(sdd->src_clk);
1551
1552 return 0;
1553 }
1554
1555 static int s3c64xx_spi_runtime_resume(struct device *dev)
1556 {
1557 struct spi_master *master = dev_get_drvdata(dev);
1558 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1559
1560 clk_prepare_enable(sdd->src_clk);
1561 clk_prepare_enable(sdd->clk);
1562
1563 return 0;
1564 }
1565 #endif /* CONFIG_PM_RUNTIME */
1566
1567 static const struct dev_pm_ops s3c64xx_spi_pm = {
1568 SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume)
1569 SET_RUNTIME_PM_OPS(s3c64xx_spi_runtime_suspend,
1570 s3c64xx_spi_runtime_resume, NULL)
1571 };
1572
1573 static struct s3c64xx_spi_port_config s3c2443_spi_port_config = {
1574 .fifo_lvl_mask = { 0x7f },
1575 .rx_lvl_offset = 13,
1576 .tx_st_done = 21,
1577 .high_speed = true,
1578 };
1579
1580 static struct s3c64xx_spi_port_config s3c6410_spi_port_config = {
1581 .fifo_lvl_mask = { 0x7f, 0x7F },
1582 .rx_lvl_offset = 13,
1583 .tx_st_done = 21,
1584 };
1585
1586 static struct s3c64xx_spi_port_config s5p64x0_spi_port_config = {
1587 .fifo_lvl_mask = { 0x1ff, 0x7F },
1588 .rx_lvl_offset = 15,
1589 .tx_st_done = 25,
1590 };
1591
1592 static struct s3c64xx_spi_port_config s5pc100_spi_port_config = {
1593 .fifo_lvl_mask = { 0x7f, 0x7F },
1594 .rx_lvl_offset = 13,
1595 .tx_st_done = 21,
1596 .high_speed = true,
1597 };
1598
1599 static struct s3c64xx_spi_port_config s5pv210_spi_port_config = {
1600 .fifo_lvl_mask = { 0x1ff, 0x7F },
1601 .rx_lvl_offset = 15,
1602 .tx_st_done = 25,
1603 .high_speed = true,
1604 };
1605
1606 static struct s3c64xx_spi_port_config exynos4_spi_port_config = {
1607 .fifo_lvl_mask = { 0x1ff, 0x7F, 0x7F },
1608 .rx_lvl_offset = 15,
1609 .tx_st_done = 25,
1610 .high_speed = true,
1611 .clk_from_cmu = true,
1612 };
1613
1614 static struct s3c64xx_spi_port_config exynos5440_spi_port_config = {
1615 .fifo_lvl_mask = { 0x1ff },
1616 .rx_lvl_offset = 15,
1617 .tx_st_done = 25,
1618 .high_speed = true,
1619 .clk_from_cmu = true,
1620 .quirks = S3C64XX_SPI_QUIRK_POLL,
1621 };
1622
1623 static struct platform_device_id s3c64xx_spi_driver_ids[] = {
1624 {
1625 .name = "s3c2443-spi",
1626 .driver_data = (kernel_ulong_t)&s3c2443_spi_port_config,
1627 }, {
1628 .name = "s3c6410-spi",
1629 .driver_data = (kernel_ulong_t)&s3c6410_spi_port_config,
1630 }, {
1631 .name = "s5p64x0-spi",
1632 .driver_data = (kernel_ulong_t)&s5p64x0_spi_port_config,
1633 }, {
1634 .name = "s5pc100-spi",
1635 .driver_data = (kernel_ulong_t)&s5pc100_spi_port_config,
1636 }, {
1637 .name = "s5pv210-spi",
1638 .driver_data = (kernel_ulong_t)&s5pv210_spi_port_config,
1639 }, {
1640 .name = "exynos4210-spi",
1641 .driver_data = (kernel_ulong_t)&exynos4_spi_port_config,
1642 },
1643 { },
1644 };
1645
1646 static const struct of_device_id s3c64xx_spi_dt_match[] = {
1647 { .compatible = "samsung,exynos4210-spi",
1648 .data = (void *)&exynos4_spi_port_config,
1649 },
1650 { .compatible = "samsung,exynos5440-spi",
1651 .data = (void *)&exynos5440_spi_port_config,
1652 },
1653 { },
1654 };
1655 MODULE_DEVICE_TABLE(of, s3c64xx_spi_dt_match);
1656
1657 static struct platform_driver s3c64xx_spi_driver = {
1658 .driver = {
1659 .name = "s3c64xx-spi",
1660 .owner = THIS_MODULE,
1661 .pm = &s3c64xx_spi_pm,
1662 .of_match_table = of_match_ptr(s3c64xx_spi_dt_match),
1663 },
1664 .remove = s3c64xx_spi_remove,
1665 .id_table = s3c64xx_spi_driver_ids,
1666 };
1667 MODULE_ALIAS("platform:s3c64xx-spi");
1668
1669 static int __init s3c64xx_spi_init(void)
1670 {
1671 return platform_driver_probe(&s3c64xx_spi_driver, s3c64xx_spi_probe);
1672 }
1673 subsys_initcall(s3c64xx_spi_init);
1674
1675 static void __exit s3c64xx_spi_exit(void)
1676 {
1677 platform_driver_unregister(&s3c64xx_spi_driver);
1678 }
1679 module_exit(s3c64xx_spi_exit);
1680
1681 MODULE_AUTHOR("Jaswinder Singh <jassi.brar@samsung.com>");
1682 MODULE_DESCRIPTION("S3C64XX SPI Controller Driver");
1683 MODULE_LICENSE("GPL");
Linux with added FPC-III support