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1// SPDX-License-Identifier: GPL-2.0+
2//
3// Copyright (c) 2009 Samsung Electronics Co., Ltd.
4// Jaswinder Singh <jassi.brar@samsung.com>
5
6#include <linux/init.h>
7#include <linux/module.h>
8#include <linux/interrupt.h>
9#include <linux/delay.h>
10#include <linux/clk.h>
11#include <linux/dma-mapping.h>
12#include <linux/dmaengine.h>
13#include <linux/platform_device.h>
14#include <linux/pm_runtime.h>
15#include <linux/spi/spi.h>
16#include <linux/of.h>
17
18#include <linux/platform_data/spi-s3c64xx.h>
19
20#define MAX_SPI_PORTS 12
21#define S3C64XX_SPI_QUIRK_CS_AUTO (1 << 1)
22#define AUTOSUSPEND_TIMEOUT 2000
23
24/* Registers and bit-fields */
25
26#define S3C64XX_SPI_CH_CFG 0x00
27#define S3C64XX_SPI_CLK_CFG 0x04
28#define S3C64XX_SPI_MODE_CFG 0x08
29#define S3C64XX_SPI_CS_REG 0x0C
30#define S3C64XX_SPI_INT_EN 0x10
31#define S3C64XX_SPI_STATUS 0x14
32#define S3C64XX_SPI_TX_DATA 0x18
33#define S3C64XX_SPI_RX_DATA 0x1C
34#define S3C64XX_SPI_PACKET_CNT 0x20
35#define S3C64XX_SPI_PENDING_CLR 0x24
36#define S3C64XX_SPI_SWAP_CFG 0x28
37#define S3C64XX_SPI_FB_CLK 0x2C
38
39#define S3C64XX_SPI_CH_HS_EN (1<<6) /* High Speed Enable */
40#define S3C64XX_SPI_CH_SW_RST (1<<5)
41#define S3C64XX_SPI_CH_SLAVE (1<<4)
42#define S3C64XX_SPI_CPOL_L (1<<3)
43#define S3C64XX_SPI_CPHA_B (1<<2)
44#define S3C64XX_SPI_CH_RXCH_ON (1<<1)
45#define S3C64XX_SPI_CH_TXCH_ON (1<<0)
46
47#define S3C64XX_SPI_CLKSEL_SRCMSK (3<<9)
48#define S3C64XX_SPI_CLKSEL_SRCSHFT 9
49#define S3C64XX_SPI_ENCLK_ENABLE (1<<8)
50#define S3C64XX_SPI_PSR_MASK 0xff
51
52#define S3C64XX_SPI_MODE_CH_TSZ_BYTE (0<<29)
53#define S3C64XX_SPI_MODE_CH_TSZ_HALFWORD (1<<29)
54#define S3C64XX_SPI_MODE_CH_TSZ_WORD (2<<29)
55#define S3C64XX_SPI_MODE_CH_TSZ_MASK (3<<29)
56#define S3C64XX_SPI_MODE_BUS_TSZ_BYTE (0<<17)
57#define S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD (1<<17)
58#define S3C64XX_SPI_MODE_BUS_TSZ_WORD (2<<17)
59#define S3C64XX_SPI_MODE_BUS_TSZ_MASK (3<<17)
60#define S3C64XX_SPI_MODE_RX_RDY_LVL GENMASK(16, 11)
61#define S3C64XX_SPI_MODE_RX_RDY_LVL_SHIFT 11
62#define S3C64XX_SPI_MODE_SELF_LOOPBACK (1<<3)
63#define S3C64XX_SPI_MODE_RXDMA_ON (1<<2)
64#define S3C64XX_SPI_MODE_TXDMA_ON (1<<1)
65#define S3C64XX_SPI_MODE_4BURST (1<<0)
66
67#define S3C64XX_SPI_CS_NSC_CNT_2 (2<<4)
68#define S3C64XX_SPI_CS_AUTO (1<<1)
69#define S3C64XX_SPI_CS_SIG_INACT (1<<0)
70
71#define S3C64XX_SPI_INT_TRAILING_EN (1<<6)
72#define S3C64XX_SPI_INT_RX_OVERRUN_EN (1<<5)
73#define S3C64XX_SPI_INT_RX_UNDERRUN_EN (1<<4)
74#define S3C64XX_SPI_INT_TX_OVERRUN_EN (1<<3)
75#define S3C64XX_SPI_INT_TX_UNDERRUN_EN (1<<2)
76#define S3C64XX_SPI_INT_RX_FIFORDY_EN (1<<1)
77#define S3C64XX_SPI_INT_TX_FIFORDY_EN (1<<0)
78
79#define S3C64XX_SPI_ST_RX_OVERRUN_ERR (1<<5)
80#define S3C64XX_SPI_ST_RX_UNDERRUN_ERR (1<<4)
81#define S3C64XX_SPI_ST_TX_OVERRUN_ERR (1<<3)
82#define S3C64XX_SPI_ST_TX_UNDERRUN_ERR (1<<2)
83#define S3C64XX_SPI_ST_RX_FIFORDY (1<<1)
84#define S3C64XX_SPI_ST_TX_FIFORDY (1<<0)
85
86#define S3C64XX_SPI_PACKET_CNT_EN (1<<16)
87#define S3C64XX_SPI_PACKET_CNT_MASK GENMASK(15, 0)
88
89#define S3C64XX_SPI_PND_TX_UNDERRUN_CLR (1<<4)
90#define S3C64XX_SPI_PND_TX_OVERRUN_CLR (1<<3)
91#define S3C64XX_SPI_PND_RX_UNDERRUN_CLR (1<<2)
92#define S3C64XX_SPI_PND_RX_OVERRUN_CLR (1<<1)
93#define S3C64XX_SPI_PND_TRAILING_CLR (1<<0)
94
95#define S3C64XX_SPI_SWAP_RX_HALF_WORD (1<<7)
96#define S3C64XX_SPI_SWAP_RX_BYTE (1<<6)
97#define S3C64XX_SPI_SWAP_RX_BIT (1<<5)
98#define S3C64XX_SPI_SWAP_RX_EN (1<<4)
99#define S3C64XX_SPI_SWAP_TX_HALF_WORD (1<<3)
100#define S3C64XX_SPI_SWAP_TX_BYTE (1<<2)
101#define S3C64XX_SPI_SWAP_TX_BIT (1<<1)
102#define S3C64XX_SPI_SWAP_TX_EN (1<<0)
103
104#define S3C64XX_SPI_FBCLK_MSK (3<<0)
105
106#define FIFO_LVL_MASK(i) ((i)->port_conf->fifo_lvl_mask[i->port_id])
107#define S3C64XX_SPI_ST_TX_DONE(v, i) (((v) & \
108 (1 << (i)->port_conf->tx_st_done)) ? 1 : 0)
109#define TX_FIFO_LVL(v, i) (((v) >> 6) & FIFO_LVL_MASK(i))
110#define RX_FIFO_LVL(v, i) (((v) >> (i)->port_conf->rx_lvl_offset) & \
111 FIFO_LVL_MASK(i))
112
113#define S3C64XX_SPI_MAX_TRAILCNT 0x3ff
114#define S3C64XX_SPI_TRAILCNT_OFF 19
115
116#define S3C64XX_SPI_TRAILCNT S3C64XX_SPI_MAX_TRAILCNT
117
118#define S3C64XX_SPI_POLLING_SIZE 32
119
120#define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
121#define is_polling(x) (x->cntrlr_info->polling)
122
123#define RXBUSY (1<<2)
124#define TXBUSY (1<<3)
125
126struct s3c64xx_spi_dma_data {
127 struct dma_chan *ch;
128 dma_cookie_t cookie;
129 enum dma_transfer_direction direction;
130};
131
132/**
133 * struct s3c64xx_spi_port_config - SPI Controller hardware info
134 * @fifo_lvl_mask: Bit-mask for {TX|RX}_FIFO_LVL bits in SPI_STATUS register.
135 * @rx_lvl_offset: Bit offset of RX_FIFO_LVL bits in SPI_STATUS regiter.
136 * @tx_st_done: Bit offset of TX_DONE bit in SPI_STATUS regiter.
137 * @clk_div: Internal clock divider
138 * @quirks: Bitmask of known quirks
139 * @high_speed: True, if the controller supports HIGH_SPEED_EN bit.
140 * @clk_from_cmu: True, if the controller does not include a clock mux and
141 * prescaler unit.
142 * @clk_ioclk: True if clock is present on this device
143 * @has_loopback: True if loopback mode can be supported
144 *
145 * The Samsung s3c64xx SPI controller are used on various Samsung SoC's but
146 * differ in some aspects such as the size of the fifo and spi bus clock
147 * setup. Such differences are specified to the driver using this structure
148 * which is provided as driver data to the driver.
149 */
150struct s3c64xx_spi_port_config {
151 int fifo_lvl_mask[MAX_SPI_PORTS];
152 int rx_lvl_offset;
153 int tx_st_done;
154 int quirks;
155 int clk_div;
156 bool high_speed;
157 bool clk_from_cmu;
158 bool clk_ioclk;
159 bool has_loopback;
160};
161
162/**
163 * struct s3c64xx_spi_driver_data - Runtime info holder for SPI driver.
164 * @clk: Pointer to the spi clock.
165 * @src_clk: Pointer to the clock used to generate SPI signals.
166 * @ioclk: Pointer to the i/o clock between host and target
167 * @pdev: Pointer to device's platform device data
168 * @host: Pointer to the SPI Protocol host.
169 * @cntrlr_info: Platform specific data for the controller this driver manages.
170 * @lock: Controller specific lock.
171 * @state: Set of FLAGS to indicate status.
172 * @sfr_start: BUS address of SPI controller regs.
173 * @regs: Pointer to ioremap'ed controller registers.
174 * @xfer_completion: To indicate completion of xfer task.
175 * @cur_mode: Stores the active configuration of the controller.
176 * @cur_bpw: Stores the active bits per word settings.
177 * @cur_speed: Current clock speed
178 * @rx_dma: Local receive DMA data (e.g. chan and direction)
179 * @tx_dma: Local transmit DMA data (e.g. chan and direction)
180 * @port_conf: Local SPI port configuartion data
181 * @port_id: Port identification number
182 */
183struct s3c64xx_spi_driver_data {
184 void __iomem *regs;
185 struct clk *clk;
186 struct clk *src_clk;
187 struct clk *ioclk;
188 struct platform_device *pdev;
189 struct spi_controller *host;
190 struct s3c64xx_spi_info *cntrlr_info;
191 spinlock_t lock;
192 unsigned long sfr_start;
193 struct completion xfer_completion;
194 unsigned state;
195 unsigned cur_mode, cur_bpw;
196 unsigned cur_speed;
197 struct s3c64xx_spi_dma_data rx_dma;
198 struct s3c64xx_spi_dma_data tx_dma;
199 const struct s3c64xx_spi_port_config *port_conf;
200 unsigned int port_id;
201};
202
203static void s3c64xx_flush_fifo(struct s3c64xx_spi_driver_data *sdd)
204{
205 void __iomem *regs = sdd->regs;
206 unsigned long loops;
207 u32 val;
208
209 writel(0, regs + S3C64XX_SPI_PACKET_CNT);
210
211 val = readl(regs + S3C64XX_SPI_CH_CFG);
212 val &= ~(S3C64XX_SPI_CH_RXCH_ON | S3C64XX_SPI_CH_TXCH_ON);
213 writel(val, regs + S3C64XX_SPI_CH_CFG);
214
215 val = readl(regs + S3C64XX_SPI_CH_CFG);
216 val |= S3C64XX_SPI_CH_SW_RST;
217 val &= ~S3C64XX_SPI_CH_HS_EN;
218 writel(val, regs + S3C64XX_SPI_CH_CFG);
219
220 /* Flush TxFIFO*/
221 loops = msecs_to_loops(1);
222 do {
223 val = readl(regs + S3C64XX_SPI_STATUS);
224 } while (TX_FIFO_LVL(val, sdd) && loops--);
225
226 if (loops == 0)
227 dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n");
228
229 /* Flush RxFIFO*/
230 loops = msecs_to_loops(1);
231 do {
232 val = readl(regs + S3C64XX_SPI_STATUS);
233 if (RX_FIFO_LVL(val, sdd))
234 readl(regs + S3C64XX_SPI_RX_DATA);
235 else
236 break;
237 } while (loops--);
238
239 if (loops == 0)
240 dev_warn(&sdd->pdev->dev, "Timed out flushing RX FIFO\n");
241
242 val = readl(regs + S3C64XX_SPI_CH_CFG);
243 val &= ~S3C64XX_SPI_CH_SW_RST;
244 writel(val, regs + S3C64XX_SPI_CH_CFG);
245
246 val = readl(regs + S3C64XX_SPI_MODE_CFG);
247 val &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
248 writel(val, regs + S3C64XX_SPI_MODE_CFG);
249}
250
251static void s3c64xx_spi_dmacb(void *data)
252{
253 struct s3c64xx_spi_driver_data *sdd;
254 struct s3c64xx_spi_dma_data *dma = data;
255 unsigned long flags;
256
257 if (dma->direction == DMA_DEV_TO_MEM)
258 sdd = container_of(data,
259 struct s3c64xx_spi_driver_data, rx_dma);
260 else
261 sdd = container_of(data,
262 struct s3c64xx_spi_driver_data, tx_dma);
263
264 spin_lock_irqsave(&sdd->lock, flags);
265
266 if (dma->direction == DMA_DEV_TO_MEM) {
267 sdd->state &= ~RXBUSY;
268 if (!(sdd->state & TXBUSY))
269 complete(&sdd->xfer_completion);
270 } else {
271 sdd->state &= ~TXBUSY;
272 if (!(sdd->state & RXBUSY))
273 complete(&sdd->xfer_completion);
274 }
275
276 spin_unlock_irqrestore(&sdd->lock, flags);
277}
278
279static int prepare_dma(struct s3c64xx_spi_dma_data *dma,
280 struct sg_table *sgt)
281{
282 struct s3c64xx_spi_driver_data *sdd;
283 struct dma_slave_config config;
284 struct dma_async_tx_descriptor *desc;
285 int ret;
286
287 memset(&config, 0, sizeof(config));
288
289 if (dma->direction == DMA_DEV_TO_MEM) {
290 sdd = container_of((void *)dma,
291 struct s3c64xx_spi_driver_data, rx_dma);
292 config.direction = dma->direction;
293 config.src_addr = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
294 config.src_addr_width = sdd->cur_bpw / 8;
295 config.src_maxburst = 1;
296 dmaengine_slave_config(dma->ch, &config);
297 } else {
298 sdd = container_of((void *)dma,
299 struct s3c64xx_spi_driver_data, tx_dma);
300 config.direction = dma->direction;
301 config.dst_addr = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
302 config.dst_addr_width = sdd->cur_bpw / 8;
303 config.dst_maxburst = 1;
304 dmaengine_slave_config(dma->ch, &config);
305 }
306
307 desc = dmaengine_prep_slave_sg(dma->ch, sgt->sgl, sgt->nents,
308 dma->direction, DMA_PREP_INTERRUPT);
309 if (!desc) {
310 dev_err(&sdd->pdev->dev, "unable to prepare %s scatterlist",
311 dma->direction == DMA_DEV_TO_MEM ? "rx" : "tx");
312 return -ENOMEM;
313 }
314
315 desc->callback = s3c64xx_spi_dmacb;
316 desc->callback_param = dma;
317
318 dma->cookie = dmaengine_submit(desc);
319 ret = dma_submit_error(dma->cookie);
320 if (ret) {
321 dev_err(&sdd->pdev->dev, "DMA submission failed");
322 return -EIO;
323 }
324
325 dma_async_issue_pending(dma->ch);
326 return 0;
327}
328
329static void s3c64xx_spi_set_cs(struct spi_device *spi, bool enable)
330{
331 struct s3c64xx_spi_driver_data *sdd =
332 spi_controller_get_devdata(spi->controller);
333
334 if (sdd->cntrlr_info->no_cs)
335 return;
336
337 if (enable) {
338 if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO)) {
339 writel(0, sdd->regs + S3C64XX_SPI_CS_REG);
340 } else {
341 u32 ssel = readl(sdd->regs + S3C64XX_SPI_CS_REG);
342
343 ssel |= (S3C64XX_SPI_CS_AUTO |
344 S3C64XX_SPI_CS_NSC_CNT_2);
345 writel(ssel, sdd->regs + S3C64XX_SPI_CS_REG);
346 }
347 } else {
348 if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
349 writel(S3C64XX_SPI_CS_SIG_INACT,
350 sdd->regs + S3C64XX_SPI_CS_REG);
351 }
352}
353
354static int s3c64xx_spi_prepare_transfer(struct spi_controller *spi)
355{
356 struct s3c64xx_spi_driver_data *sdd = spi_controller_get_devdata(spi);
357
358 if (is_polling(sdd))
359 return 0;
360
361 /* Requests DMA channels */
362 sdd->rx_dma.ch = dma_request_chan(&sdd->pdev->dev, "rx");
363 if (IS_ERR(sdd->rx_dma.ch)) {
364 dev_err(&sdd->pdev->dev, "Failed to get RX DMA channel\n");
365 sdd->rx_dma.ch = NULL;
366 return 0;
367 }
368
369 sdd->tx_dma.ch = dma_request_chan(&sdd->pdev->dev, "tx");
370 if (IS_ERR(sdd->tx_dma.ch)) {
371 dev_err(&sdd->pdev->dev, "Failed to get TX DMA channel\n");
372 dma_release_channel(sdd->rx_dma.ch);
373 sdd->tx_dma.ch = NULL;
374 sdd->rx_dma.ch = NULL;
375 return 0;
376 }
377
378 spi->dma_rx = sdd->rx_dma.ch;
379 spi->dma_tx = sdd->tx_dma.ch;
380
381 return 0;
382}
383
384static int s3c64xx_spi_unprepare_transfer(struct spi_controller *spi)
385{
386 struct s3c64xx_spi_driver_data *sdd = spi_controller_get_devdata(spi);
387
388 if (is_polling(sdd))
389 return 0;
390
391 /* Releases DMA channels if they are allocated */
392 if (sdd->rx_dma.ch && sdd->tx_dma.ch) {
393 dma_release_channel(sdd->rx_dma.ch);
394 dma_release_channel(sdd->tx_dma.ch);
395 sdd->rx_dma.ch = NULL;
396 sdd->tx_dma.ch = NULL;
397 }
398
399 return 0;
400}
401
402static bool s3c64xx_spi_can_dma(struct spi_controller *host,
403 struct spi_device *spi,
404 struct spi_transfer *xfer)
405{
406 struct s3c64xx_spi_driver_data *sdd = spi_controller_get_devdata(host);
407
408 if (sdd->rx_dma.ch && sdd->tx_dma.ch) {
409 return xfer->len > (FIFO_LVL_MASK(sdd) >> 1) + 1;
410 } else {
411 return false;
412 }
413
414}
415
416static int s3c64xx_enable_datapath(struct s3c64xx_spi_driver_data *sdd,
417 struct spi_transfer *xfer, int dma_mode)
418{
419 void __iomem *regs = sdd->regs;
420 u32 modecfg, chcfg;
421 int ret = 0;
422
423 modecfg = readl(regs + S3C64XX_SPI_MODE_CFG);
424 modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
425
426 chcfg = readl(regs + S3C64XX_SPI_CH_CFG);
427 chcfg &= ~S3C64XX_SPI_CH_TXCH_ON;
428
429 if (dma_mode) {
430 chcfg &= ~S3C64XX_SPI_CH_RXCH_ON;
431 } else {
432 /* Always shift in data in FIFO, even if xfer is Tx only,
433 * this helps setting PCKT_CNT value for generating clocks
434 * as exactly needed.
435 */
436 chcfg |= S3C64XX_SPI_CH_RXCH_ON;
437 writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
438 | S3C64XX_SPI_PACKET_CNT_EN,
439 regs + S3C64XX_SPI_PACKET_CNT);
440 }
441
442 if (xfer->tx_buf != NULL) {
443 sdd->state |= TXBUSY;
444 chcfg |= S3C64XX_SPI_CH_TXCH_ON;
445 if (dma_mode) {
446 modecfg |= S3C64XX_SPI_MODE_TXDMA_ON;
447 ret = prepare_dma(&sdd->tx_dma, &xfer->tx_sg);
448 } else {
449 switch (sdd->cur_bpw) {
450 case 32:
451 iowrite32_rep(regs + S3C64XX_SPI_TX_DATA,
452 xfer->tx_buf, xfer->len / 4);
453 break;
454 case 16:
455 iowrite16_rep(regs + S3C64XX_SPI_TX_DATA,
456 xfer->tx_buf, xfer->len / 2);
457 break;
458 default:
459 iowrite8_rep(regs + S3C64XX_SPI_TX_DATA,
460 xfer->tx_buf, xfer->len);
461 break;
462 }
463 }
464 }
465
466 if (xfer->rx_buf != NULL) {
467 sdd->state |= RXBUSY;
468
469 if (sdd->port_conf->high_speed && sdd->cur_speed >= 30000000UL
470 && !(sdd->cur_mode & SPI_CPHA))
471 chcfg |= S3C64XX_SPI_CH_HS_EN;
472
473 if (dma_mode) {
474 modecfg |= S3C64XX_SPI_MODE_RXDMA_ON;
475 chcfg |= S3C64XX_SPI_CH_RXCH_ON;
476 writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
477 | S3C64XX_SPI_PACKET_CNT_EN,
478 regs + S3C64XX_SPI_PACKET_CNT);
479 ret = prepare_dma(&sdd->rx_dma, &xfer->rx_sg);
480 }
481 }
482
483 if (ret)
484 return ret;
485
486 writel(modecfg, regs + S3C64XX_SPI_MODE_CFG);
487 writel(chcfg, regs + S3C64XX_SPI_CH_CFG);
488
489 return 0;
490}
491
492static u32 s3c64xx_spi_wait_for_timeout(struct s3c64xx_spi_driver_data *sdd,
493 int timeout_ms)
494{
495 void __iomem *regs = sdd->regs;
496 unsigned long val = 1;
497 u32 status;
498
499 /* max fifo depth available */
500 u32 max_fifo = (FIFO_LVL_MASK(sdd) >> 1) + 1;
501
502 if (timeout_ms)
503 val = msecs_to_loops(timeout_ms);
504
505 do {
506 status = readl(regs + S3C64XX_SPI_STATUS);
507 } while (RX_FIFO_LVL(status, sdd) < max_fifo && --val);
508
509 /* return the actual received data length */
510 return RX_FIFO_LVL(status, sdd);
511}
512
513static int s3c64xx_wait_for_dma(struct s3c64xx_spi_driver_data *sdd,
514 struct spi_transfer *xfer)
515{
516 void __iomem *regs = sdd->regs;
517 unsigned long val;
518 u32 status;
519 int ms;
520
521 /* millisecs to xfer 'len' bytes @ 'cur_speed' */
522 ms = xfer->len * 8 * 1000 / sdd->cur_speed;
523 ms += 30; /* some tolerance */
524 ms = max(ms, 100); /* minimum timeout */
525
526 val = msecs_to_jiffies(ms) + 10;
527 val = wait_for_completion_timeout(&sdd->xfer_completion, val);
528
529 /*
530 * If the previous xfer was completed within timeout, then
531 * proceed further else return -EIO.
532 * DmaTx returns after simply writing data in the FIFO,
533 * w/o waiting for real transmission on the bus to finish.
534 * DmaRx returns only after Dma read data from FIFO which
535 * needs bus transmission to finish, so we don't worry if
536 * Xfer involved Rx(with or without Tx).
537 */
538 if (val && !xfer->rx_buf) {
539 val = msecs_to_loops(10);
540 status = readl(regs + S3C64XX_SPI_STATUS);
541 while ((TX_FIFO_LVL(status, sdd)
542 || !S3C64XX_SPI_ST_TX_DONE(status, sdd))
543 && --val) {
544 cpu_relax();
545 status = readl(regs + S3C64XX_SPI_STATUS);
546 }
547
548 }
549
550 /* If timed out while checking rx/tx status return error */
551 if (!val)
552 return -EIO;
553
554 return 0;
555}
556
557static int s3c64xx_wait_for_pio(struct s3c64xx_spi_driver_data *sdd,
558 struct spi_transfer *xfer, bool use_irq)
559{
560 void __iomem *regs = sdd->regs;
561 unsigned long val;
562 u32 status;
563 int loops;
564 u32 cpy_len;
565 u8 *buf;
566 int ms;
567 unsigned long time_us;
568
569 /* microsecs to xfer 'len' bytes @ 'cur_speed' */
570 time_us = (xfer->len * 8 * 1000 * 1000) / sdd->cur_speed;
571 ms = (time_us / 1000);
572 ms += 10; /* some tolerance */
573
574 /* sleep during signal transfer time */
575 status = readl(regs + S3C64XX_SPI_STATUS);
576 if (RX_FIFO_LVL(status, sdd) < xfer->len)
577 usleep_range(time_us / 2, time_us);
578
579 if (use_irq) {
580 val = msecs_to_jiffies(ms);
581 if (!wait_for_completion_timeout(&sdd->xfer_completion, val))
582 return -EIO;
583 }
584
585 val = msecs_to_loops(ms);
586 do {
587 status = readl(regs + S3C64XX_SPI_STATUS);
588 } while (RX_FIFO_LVL(status, sdd) < xfer->len && --val);
589
590 if (!val)
591 return -EIO;
592
593 /* If it was only Tx */
594 if (!xfer->rx_buf) {
595 sdd->state &= ~TXBUSY;
596 return 0;
597 }
598
599 /*
600 * If the receive length is bigger than the controller fifo
601 * size, calculate the loops and read the fifo as many times.
602 * loops = length / max fifo size (calculated by using the
603 * fifo mask).
604 * For any size less than the fifo size the below code is
605 * executed atleast once.
606 */
607 loops = xfer->len / ((FIFO_LVL_MASK(sdd) >> 1) + 1);
608 buf = xfer->rx_buf;
609 do {
610 /* wait for data to be received in the fifo */
611 cpy_len = s3c64xx_spi_wait_for_timeout(sdd,
612 (loops ? ms : 0));
613
614 switch (sdd->cur_bpw) {
615 case 32:
616 ioread32_rep(regs + S3C64XX_SPI_RX_DATA,
617 buf, cpy_len / 4);
618 break;
619 case 16:
620 ioread16_rep(regs + S3C64XX_SPI_RX_DATA,
621 buf, cpy_len / 2);
622 break;
623 default:
624 ioread8_rep(regs + S3C64XX_SPI_RX_DATA,
625 buf, cpy_len);
626 break;
627 }
628
629 buf = buf + cpy_len;
630 } while (loops--);
631 sdd->state &= ~RXBUSY;
632
633 return 0;
634}
635
636static int s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
637{
638 void __iomem *regs = sdd->regs;
639 int ret;
640 u32 val;
641 int div = sdd->port_conf->clk_div;
642
643 /* Disable Clock */
644 if (!sdd->port_conf->clk_from_cmu) {
645 val = readl(regs + S3C64XX_SPI_CLK_CFG);
646 val &= ~S3C64XX_SPI_ENCLK_ENABLE;
647 writel(val, regs + S3C64XX_SPI_CLK_CFG);
648 }
649
650 /* Set Polarity and Phase */
651 val = readl(regs + S3C64XX_SPI_CH_CFG);
652 val &= ~(S3C64XX_SPI_CH_SLAVE |
653 S3C64XX_SPI_CPOL_L |
654 S3C64XX_SPI_CPHA_B);
655
656 if (sdd->cur_mode & SPI_CPOL)
657 val |= S3C64XX_SPI_CPOL_L;
658
659 if (sdd->cur_mode & SPI_CPHA)
660 val |= S3C64XX_SPI_CPHA_B;
661
662 writel(val, regs + S3C64XX_SPI_CH_CFG);
663
664 /* Set Channel & DMA Mode */
665 val = readl(regs + S3C64XX_SPI_MODE_CFG);
666 val &= ~(S3C64XX_SPI_MODE_BUS_TSZ_MASK
667 | S3C64XX_SPI_MODE_CH_TSZ_MASK);
668
669 switch (sdd->cur_bpw) {
670 case 32:
671 val |= S3C64XX_SPI_MODE_BUS_TSZ_WORD;
672 val |= S3C64XX_SPI_MODE_CH_TSZ_WORD;
673 break;
674 case 16:
675 val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD;
676 val |= S3C64XX_SPI_MODE_CH_TSZ_HALFWORD;
677 break;
678 default:
679 val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE;
680 val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE;
681 break;
682 }
683
684 if ((sdd->cur_mode & SPI_LOOP) && sdd->port_conf->has_loopback)
685 val |= S3C64XX_SPI_MODE_SELF_LOOPBACK;
686 else
687 val &= ~S3C64XX_SPI_MODE_SELF_LOOPBACK;
688
689 writel(val, regs + S3C64XX_SPI_MODE_CFG);
690
691 if (sdd->port_conf->clk_from_cmu) {
692 ret = clk_set_rate(sdd->src_clk, sdd->cur_speed * div);
693 if (ret)
694 return ret;
695 sdd->cur_speed = clk_get_rate(sdd->src_clk) / div;
696 } else {
697 /* Configure Clock */
698 val = readl(regs + S3C64XX_SPI_CLK_CFG);
699 val &= ~S3C64XX_SPI_PSR_MASK;
700 val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / div - 1)
701 & S3C64XX_SPI_PSR_MASK);
702 writel(val, regs + S3C64XX_SPI_CLK_CFG);
703
704 /* Enable Clock */
705 val = readl(regs + S3C64XX_SPI_CLK_CFG);
706 val |= S3C64XX_SPI_ENCLK_ENABLE;
707 writel(val, regs + S3C64XX_SPI_CLK_CFG);
708 }
709
710 return 0;
711}
712
713#define XFER_DMAADDR_INVALID DMA_BIT_MASK(32)
714
715static int s3c64xx_spi_prepare_message(struct spi_controller *host,
716 struct spi_message *msg)
717{
718 struct s3c64xx_spi_driver_data *sdd = spi_controller_get_devdata(host);
719 struct spi_device *spi = msg->spi;
720 struct s3c64xx_spi_csinfo *cs = spi->controller_data;
721
722 /* Configure feedback delay */
723 if (!cs)
724 /* No delay if not defined */
725 writel(0, sdd->regs + S3C64XX_SPI_FB_CLK);
726 else
727 writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK);
728
729 return 0;
730}
731
732static size_t s3c64xx_spi_max_transfer_size(struct spi_device *spi)
733{
734 struct spi_controller *ctlr = spi->controller;
735
736 return ctlr->can_dma ? S3C64XX_SPI_PACKET_CNT_MASK : SIZE_MAX;
737}
738
739static int s3c64xx_spi_transfer_one(struct spi_controller *host,
740 struct spi_device *spi,
741 struct spi_transfer *xfer)
742{
743 struct s3c64xx_spi_driver_data *sdd = spi_controller_get_devdata(host);
744 const unsigned int fifo_len = (FIFO_LVL_MASK(sdd) >> 1) + 1;
745 const void *tx_buf = NULL;
746 void *rx_buf = NULL;
747 int target_len = 0, origin_len = 0;
748 int use_dma = 0;
749 bool use_irq = false;
750 int status;
751 u32 speed;
752 u8 bpw;
753 unsigned long flags;
754 u32 rdy_lv;
755 u32 val;
756
757 reinit_completion(&sdd->xfer_completion);
758
759 /* Only BPW and Speed may change across transfers */
760 bpw = xfer->bits_per_word;
761 speed = xfer->speed_hz;
762
763 if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) {
764 sdd->cur_bpw = bpw;
765 sdd->cur_speed = speed;
766 sdd->cur_mode = spi->mode;
767 status = s3c64xx_spi_config(sdd);
768 if (status)
769 return status;
770 }
771
772 if (!is_polling(sdd) && (xfer->len > fifo_len) &&
773 sdd->rx_dma.ch && sdd->tx_dma.ch) {
774 use_dma = 1;
775
776 } else if (xfer->len >= fifo_len) {
777 tx_buf = xfer->tx_buf;
778 rx_buf = xfer->rx_buf;
779 origin_len = xfer->len;
780 target_len = xfer->len;
781 xfer->len = fifo_len - 1;
782 }
783
784 do {
785 /* transfer size is greater than 32, change to IRQ mode */
786 if (!use_dma && xfer->len > S3C64XX_SPI_POLLING_SIZE)
787 use_irq = true;
788
789 if (use_irq) {
790 reinit_completion(&sdd->xfer_completion);
791
792 rdy_lv = xfer->len;
793 /* Setup RDY_FIFO trigger Level
794 * RDY_LVL =
795 * fifo_lvl up to 64 byte -> N bytes
796 * 128 byte -> RDY_LVL * 2 bytes
797 * 256 byte -> RDY_LVL * 4 bytes
798 */
799 if (fifo_len == 128)
800 rdy_lv /= 2;
801 else if (fifo_len == 256)
802 rdy_lv /= 4;
803
804 val = readl(sdd->regs + S3C64XX_SPI_MODE_CFG);
805 val &= ~S3C64XX_SPI_MODE_RX_RDY_LVL;
806 val |= (rdy_lv << S3C64XX_SPI_MODE_RX_RDY_LVL_SHIFT);
807 writel(val, sdd->regs + S3C64XX_SPI_MODE_CFG);
808
809 /* Enable FIFO_RDY_EN IRQ */
810 val = readl(sdd->regs + S3C64XX_SPI_INT_EN);
811 writel((val | S3C64XX_SPI_INT_RX_FIFORDY_EN),
812 sdd->regs + S3C64XX_SPI_INT_EN);
813
814 }
815
816 spin_lock_irqsave(&sdd->lock, flags);
817
818 /* Pending only which is to be done */
819 sdd->state &= ~RXBUSY;
820 sdd->state &= ~TXBUSY;
821
822 /* Start the signals */
823 s3c64xx_spi_set_cs(spi, true);
824
825 status = s3c64xx_enable_datapath(sdd, xfer, use_dma);
826
827 spin_unlock_irqrestore(&sdd->lock, flags);
828
829 if (status) {
830 dev_err(&spi->dev, "failed to enable data path for transfer: %d\n", status);
831 break;
832 }
833
834 if (use_dma)
835 status = s3c64xx_wait_for_dma(sdd, xfer);
836 else
837 status = s3c64xx_wait_for_pio(sdd, xfer, use_irq);
838
839 if (status) {
840 dev_err(&spi->dev,
841 "I/O Error: rx-%d tx-%d rx-%c tx-%c len-%d dma-%d res-(%d)\n",
842 xfer->rx_buf ? 1 : 0, xfer->tx_buf ? 1 : 0,
843 (sdd->state & RXBUSY) ? 'f' : 'p',
844 (sdd->state & TXBUSY) ? 'f' : 'p',
845 xfer->len, use_dma ? 1 : 0, status);
846
847 if (use_dma) {
848 struct dma_tx_state s;
849
850 if (xfer->tx_buf && (sdd->state & TXBUSY)) {
851 dmaengine_pause(sdd->tx_dma.ch);
852 dmaengine_tx_status(sdd->tx_dma.ch, sdd->tx_dma.cookie, &s);
853 dmaengine_terminate_all(sdd->tx_dma.ch);
854 dev_err(&spi->dev, "TX residue: %d\n", s.residue);
855
856 }
857 if (xfer->rx_buf && (sdd->state & RXBUSY)) {
858 dmaengine_pause(sdd->rx_dma.ch);
859 dmaengine_tx_status(sdd->rx_dma.ch, sdd->rx_dma.cookie, &s);
860 dmaengine_terminate_all(sdd->rx_dma.ch);
861 dev_err(&spi->dev, "RX residue: %d\n", s.residue);
862 }
863 }
864 } else {
865 s3c64xx_flush_fifo(sdd);
866 }
867 if (target_len > 0) {
868 target_len -= xfer->len;
869
870 if (xfer->tx_buf)
871 xfer->tx_buf += xfer->len;
872
873 if (xfer->rx_buf)
874 xfer->rx_buf += xfer->len;
875
876 if (target_len >= fifo_len)
877 xfer->len = fifo_len - 1;
878 else
879 xfer->len = target_len;
880 }
881 } while (target_len > 0);
882
883 if (origin_len) {
884 /* Restore original xfer buffers and length */
885 xfer->tx_buf = tx_buf;
886 xfer->rx_buf = rx_buf;
887 xfer->len = origin_len;
888 }
889
890 return status;
891}
892
893static struct s3c64xx_spi_csinfo *s3c64xx_get_target_ctrldata(
894 struct spi_device *spi)
895{
896 struct s3c64xx_spi_csinfo *cs;
897 struct device_node *target_np, *data_np = NULL;
898 u32 fb_delay = 0;
899
900 target_np = spi->dev.of_node;
901 if (!target_np) {
902 dev_err(&spi->dev, "device node not found\n");
903 return ERR_PTR(-EINVAL);
904 }
905
906 cs = kzalloc(sizeof(*cs), GFP_KERNEL);
907 if (!cs)
908 return ERR_PTR(-ENOMEM);
909
910 data_np = of_get_child_by_name(target_np, "controller-data");
911 if (!data_np) {
912 dev_info(&spi->dev, "feedback delay set to default (0)\n");
913 return cs;
914 }
915
916 of_property_read_u32(data_np, "samsung,spi-feedback-delay", &fb_delay);
917 cs->fb_delay = fb_delay;
918 of_node_put(data_np);
919 return cs;
920}
921
922/*
923 * Here we only check the validity of requested configuration
924 * and save the configuration in a local data-structure.
925 * The controller is actually configured only just before we
926 * get a message to transfer.
927 */
928static int s3c64xx_spi_setup(struct spi_device *spi)
929{
930 struct s3c64xx_spi_csinfo *cs = spi->controller_data;
931 struct s3c64xx_spi_driver_data *sdd;
932 int err;
933 int div;
934
935 sdd = spi_controller_get_devdata(spi->controller);
936 if (spi->dev.of_node) {
937 cs = s3c64xx_get_target_ctrldata(spi);
938 spi->controller_data = cs;
939 }
940
941 /* NULL is fine, we just avoid using the FB delay (=0) */
942 if (IS_ERR(cs)) {
943 dev_err(&spi->dev, "No CS for SPI(%d)\n", spi_get_chipselect(spi, 0));
944 return -ENODEV;
945 }
946
947 if (!spi_get_ctldata(spi))
948 spi_set_ctldata(spi, cs);
949
950 pm_runtime_get_sync(&sdd->pdev->dev);
951
952 div = sdd->port_conf->clk_div;
953
954 /* Check if we can provide the requested rate */
955 if (!sdd->port_conf->clk_from_cmu) {
956 u32 psr, speed;
957
958 /* Max possible */
959 speed = clk_get_rate(sdd->src_clk) / div / (0 + 1);
960
961 if (spi->max_speed_hz > speed)
962 spi->max_speed_hz = speed;
963
964 psr = clk_get_rate(sdd->src_clk) / div / spi->max_speed_hz - 1;
965 psr &= S3C64XX_SPI_PSR_MASK;
966 if (psr == S3C64XX_SPI_PSR_MASK)
967 psr--;
968
969 speed = clk_get_rate(sdd->src_clk) / div / (psr + 1);
970 if (spi->max_speed_hz < speed) {
971 if (psr+1 < S3C64XX_SPI_PSR_MASK) {
972 psr++;
973 } else {
974 err = -EINVAL;
975 goto setup_exit;
976 }
977 }
978
979 speed = clk_get_rate(sdd->src_clk) / div / (psr + 1);
980 if (spi->max_speed_hz >= speed) {
981 spi->max_speed_hz = speed;
982 } else {
983 dev_err(&spi->dev, "Can't set %dHz transfer speed\n",
984 spi->max_speed_hz);
985 err = -EINVAL;
986 goto setup_exit;
987 }
988 }
989
990 pm_runtime_mark_last_busy(&sdd->pdev->dev);
991 pm_runtime_put_autosuspend(&sdd->pdev->dev);
992 s3c64xx_spi_set_cs(spi, false);
993
994 return 0;
995
996setup_exit:
997 pm_runtime_mark_last_busy(&sdd->pdev->dev);
998 pm_runtime_put_autosuspend(&sdd->pdev->dev);
999 /* setup() returns with device de-selected */
1000 s3c64xx_spi_set_cs(spi, false);
1001
1002 spi_set_ctldata(spi, NULL);
1003
1004 /* This was dynamically allocated on the DT path */
1005 if (spi->dev.of_node)
1006 kfree(cs);
1007
1008 return err;
1009}
1010
1011static void s3c64xx_spi_cleanup(struct spi_device *spi)
1012{
1013 struct s3c64xx_spi_csinfo *cs = spi_get_ctldata(spi);
1014
1015 /* This was dynamically allocated on the DT path */
1016 if (spi->dev.of_node)
1017 kfree(cs);
1018
1019 spi_set_ctldata(spi, NULL);
1020}
1021
1022static irqreturn_t s3c64xx_spi_irq(int irq, void *data)
1023{
1024 struct s3c64xx_spi_driver_data *sdd = data;
1025 struct spi_controller *spi = sdd->host;
1026 unsigned int val, clr = 0;
1027
1028 val = readl(sdd->regs + S3C64XX_SPI_STATUS);
1029
1030 if (val & S3C64XX_SPI_ST_RX_OVERRUN_ERR) {
1031 clr = S3C64XX_SPI_PND_RX_OVERRUN_CLR;
1032 dev_err(&spi->dev, "RX overrun\n");
1033 }
1034 if (val & S3C64XX_SPI_ST_RX_UNDERRUN_ERR) {
1035 clr |= S3C64XX_SPI_PND_RX_UNDERRUN_CLR;
1036 dev_err(&spi->dev, "RX underrun\n");
1037 }
1038 if (val & S3C64XX_SPI_ST_TX_OVERRUN_ERR) {
1039 clr |= S3C64XX_SPI_PND_TX_OVERRUN_CLR;
1040 dev_err(&spi->dev, "TX overrun\n");
1041 }
1042 if (val & S3C64XX_SPI_ST_TX_UNDERRUN_ERR) {
1043 clr |= S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
1044 dev_err(&spi->dev, "TX underrun\n");
1045 }
1046
1047 if (val & S3C64XX_SPI_ST_RX_FIFORDY) {
1048 complete(&sdd->xfer_completion);
1049 /* No pending clear irq, turn-off INT_EN_RX_FIFO_RDY */
1050 val = readl(sdd->regs + S3C64XX_SPI_INT_EN);
1051 writel((val & ~S3C64XX_SPI_INT_RX_FIFORDY_EN),
1052 sdd->regs + S3C64XX_SPI_INT_EN);
1053 }
1054
1055 /* Clear the pending irq by setting and then clearing it */
1056 writel(clr, sdd->regs + S3C64XX_SPI_PENDING_CLR);
1057 writel(0, sdd->regs + S3C64XX_SPI_PENDING_CLR);
1058
1059 return IRQ_HANDLED;
1060}
1061
1062static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd)
1063{
1064 struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1065 void __iomem *regs = sdd->regs;
1066 unsigned int val;
1067
1068 sdd->cur_speed = 0;
1069
1070 if (sci->no_cs)
1071 writel(0, sdd->regs + S3C64XX_SPI_CS_REG);
1072 else if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
1073 writel(S3C64XX_SPI_CS_SIG_INACT, sdd->regs + S3C64XX_SPI_CS_REG);
1074
1075 /* Disable Interrupts - we use Polling if not DMA mode */
1076 writel(0, regs + S3C64XX_SPI_INT_EN);
1077
1078 if (!sdd->port_conf->clk_from_cmu)
1079 writel(sci->src_clk_nr << S3C64XX_SPI_CLKSEL_SRCSHFT,
1080 regs + S3C64XX_SPI_CLK_CFG);
1081 writel(0, regs + S3C64XX_SPI_MODE_CFG);
1082 writel(0, regs + S3C64XX_SPI_PACKET_CNT);
1083
1084 /* Clear any irq pending bits, should set and clear the bits */
1085 val = S3C64XX_SPI_PND_RX_OVERRUN_CLR |
1086 S3C64XX_SPI_PND_RX_UNDERRUN_CLR |
1087 S3C64XX_SPI_PND_TX_OVERRUN_CLR |
1088 S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
1089 writel(val, regs + S3C64XX_SPI_PENDING_CLR);
1090 writel(0, regs + S3C64XX_SPI_PENDING_CLR);
1091
1092 writel(0, regs + S3C64XX_SPI_SWAP_CFG);
1093
1094 val = readl(regs + S3C64XX_SPI_MODE_CFG);
1095 val &= ~S3C64XX_SPI_MODE_4BURST;
1096 val &= ~(S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
1097 val |= (S3C64XX_SPI_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
1098 writel(val, regs + S3C64XX_SPI_MODE_CFG);
1099
1100 s3c64xx_flush_fifo(sdd);
1101}
1102
1103#ifdef CONFIG_OF
1104static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
1105{
1106 struct s3c64xx_spi_info *sci;
1107 u32 temp;
1108
1109 sci = devm_kzalloc(dev, sizeof(*sci), GFP_KERNEL);
1110 if (!sci)
1111 return ERR_PTR(-ENOMEM);
1112
1113 if (of_property_read_u32(dev->of_node, "samsung,spi-src-clk", &temp)) {
1114 dev_warn(dev, "spi bus clock parent not specified, using clock at index 0 as parent\n");
1115 sci->src_clk_nr = 0;
1116 } else {
1117 sci->src_clk_nr = temp;
1118 }
1119
1120 if (of_property_read_u32(dev->of_node, "num-cs", &temp)) {
1121 dev_warn(dev, "number of chip select lines not specified, assuming 1 chip select line\n");
1122 sci->num_cs = 1;
1123 } else {
1124 sci->num_cs = temp;
1125 }
1126
1127 sci->no_cs = of_property_read_bool(dev->of_node, "no-cs-readback");
1128 sci->polling = !of_property_present(dev->of_node, "dmas");
1129
1130 return sci;
1131}
1132#else
1133static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
1134{
1135 return dev_get_platdata(dev);
1136}
1137#endif
1138
1139static inline const struct s3c64xx_spi_port_config *s3c64xx_spi_get_port_config(
1140 struct platform_device *pdev)
1141{
1142#ifdef CONFIG_OF
1143 if (pdev->dev.of_node)
1144 return of_device_get_match_data(&pdev->dev);
1145#endif
1146 return (const struct s3c64xx_spi_port_config *)platform_get_device_id(pdev)->driver_data;
1147}
1148
1149static int s3c64xx_spi_probe(struct platform_device *pdev)
1150{
1151 struct resource *mem_res;
1152 struct s3c64xx_spi_driver_data *sdd;
1153 struct s3c64xx_spi_info *sci = dev_get_platdata(&pdev->dev);
1154 struct spi_controller *host;
1155 int ret, irq;
1156 char clk_name[16];
1157
1158 if (!sci && pdev->dev.of_node) {
1159 sci = s3c64xx_spi_parse_dt(&pdev->dev);
1160 if (IS_ERR(sci))
1161 return PTR_ERR(sci);
1162 }
1163
1164 if (!sci)
1165 return dev_err_probe(&pdev->dev, -ENODEV,
1166 "Platform_data missing!\n");
1167
1168 irq = platform_get_irq(pdev, 0);
1169 if (irq < 0)
1170 return irq;
1171
1172 host = devm_spi_alloc_host(&pdev->dev, sizeof(*sdd));
1173 if (!host)
1174 return dev_err_probe(&pdev->dev, -ENOMEM,
1175 "Unable to allocate SPI Host\n");
1176
1177 platform_set_drvdata(pdev, host);
1178
1179 sdd = spi_controller_get_devdata(host);
1180 sdd->port_conf = s3c64xx_spi_get_port_config(pdev);
1181 sdd->host = host;
1182 sdd->cntrlr_info = sci;
1183 sdd->pdev = pdev;
1184 if (pdev->dev.of_node) {
1185 ret = of_alias_get_id(pdev->dev.of_node, "spi");
1186 if (ret < 0)
1187 return dev_err_probe(&pdev->dev, ret,
1188 "Failed to get alias id\n");
1189 sdd->port_id = ret;
1190 } else {
1191 sdd->port_id = pdev->id;
1192 }
1193
1194 sdd->cur_bpw = 8;
1195
1196 sdd->tx_dma.direction = DMA_MEM_TO_DEV;
1197 sdd->rx_dma.direction = DMA_DEV_TO_MEM;
1198
1199 host->dev.of_node = pdev->dev.of_node;
1200 host->bus_num = sdd->port_id;
1201 host->setup = s3c64xx_spi_setup;
1202 host->cleanup = s3c64xx_spi_cleanup;
1203 host->prepare_transfer_hardware = s3c64xx_spi_prepare_transfer;
1204 host->unprepare_transfer_hardware = s3c64xx_spi_unprepare_transfer;
1205 host->prepare_message = s3c64xx_spi_prepare_message;
1206 host->transfer_one = s3c64xx_spi_transfer_one;
1207 host->max_transfer_size = s3c64xx_spi_max_transfer_size;
1208 host->num_chipselect = sci->num_cs;
1209 host->use_gpio_descriptors = true;
1210 host->dma_alignment = 8;
1211 host->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) |
1212 SPI_BPW_MASK(8);
1213 /* the spi->mode bits understood by this driver: */
1214 host->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1215 if (sdd->port_conf->has_loopback)
1216 host->mode_bits |= SPI_LOOP;
1217 host->auto_runtime_pm = true;
1218 if (!is_polling(sdd))
1219 host->can_dma = s3c64xx_spi_can_dma;
1220
1221 sdd->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &mem_res);
1222 if (IS_ERR(sdd->regs))
1223 return PTR_ERR(sdd->regs);
1224 sdd->sfr_start = mem_res->start;
1225
1226 if (sci->cfg_gpio && sci->cfg_gpio())
1227 return dev_err_probe(&pdev->dev, -EBUSY,
1228 "Unable to config gpio\n");
1229
1230 /* Setup clocks */
1231 sdd->clk = devm_clk_get_enabled(&pdev->dev, "spi");
1232 if (IS_ERR(sdd->clk))
1233 return dev_err_probe(&pdev->dev, PTR_ERR(sdd->clk),
1234 "Unable to acquire clock 'spi'\n");
1235
1236 sprintf(clk_name, "spi_busclk%d", sci->src_clk_nr);
1237 sdd->src_clk = devm_clk_get_enabled(&pdev->dev, clk_name);
1238 if (IS_ERR(sdd->src_clk))
1239 return dev_err_probe(&pdev->dev, PTR_ERR(sdd->src_clk),
1240 "Unable to acquire clock '%s'\n",
1241 clk_name);
1242
1243 if (sdd->port_conf->clk_ioclk) {
1244 sdd->ioclk = devm_clk_get_enabled(&pdev->dev, "spi_ioclk");
1245 if (IS_ERR(sdd->ioclk))
1246 return dev_err_probe(&pdev->dev, PTR_ERR(sdd->ioclk),
1247 "Unable to acquire 'ioclk'\n");
1248 }
1249
1250 pm_runtime_set_autosuspend_delay(&pdev->dev, AUTOSUSPEND_TIMEOUT);
1251 pm_runtime_use_autosuspend(&pdev->dev);
1252 pm_runtime_set_active(&pdev->dev);
1253 pm_runtime_enable(&pdev->dev);
1254 pm_runtime_get_sync(&pdev->dev);
1255
1256 /* Setup Deufult Mode */
1257 s3c64xx_spi_hwinit(sdd);
1258
1259 spin_lock_init(&sdd->lock);
1260 init_completion(&sdd->xfer_completion);
1261
1262 ret = devm_request_irq(&pdev->dev, irq, s3c64xx_spi_irq, 0,
1263 "spi-s3c64xx", sdd);
1264 if (ret != 0) {
1265 dev_err(&pdev->dev, "Failed to request IRQ %d: %d\n",
1266 irq, ret);
1267 goto err_pm_put;
1268 }
1269
1270 writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
1271 S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
1272 sdd->regs + S3C64XX_SPI_INT_EN);
1273
1274 ret = devm_spi_register_controller(&pdev->dev, host);
1275 if (ret != 0) {
1276 dev_err(&pdev->dev, "cannot register SPI host: %d\n", ret);
1277 goto err_pm_put;
1278 }
1279
1280 dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d with %d Targets attached\n",
1281 sdd->port_id, host->num_chipselect);
1282 dev_dbg(&pdev->dev, "\tIOmem=[%pR]\tFIFO %dbytes\n",
1283 mem_res, (FIFO_LVL_MASK(sdd) >> 1) + 1);
1284
1285 pm_runtime_mark_last_busy(&pdev->dev);
1286 pm_runtime_put_autosuspend(&pdev->dev);
1287
1288 return 0;
1289
1290err_pm_put:
1291 pm_runtime_put_noidle(&pdev->dev);
1292 pm_runtime_disable(&pdev->dev);
1293 pm_runtime_set_suspended(&pdev->dev);
1294
1295 return ret;
1296}
1297
1298static void s3c64xx_spi_remove(struct platform_device *pdev)
1299{
1300 struct spi_controller *host = platform_get_drvdata(pdev);
1301 struct s3c64xx_spi_driver_data *sdd = spi_controller_get_devdata(host);
1302
1303 pm_runtime_get_sync(&pdev->dev);
1304
1305 writel(0, sdd->regs + S3C64XX_SPI_INT_EN);
1306
1307 if (!is_polling(sdd)) {
1308 dma_release_channel(sdd->rx_dma.ch);
1309 dma_release_channel(sdd->tx_dma.ch);
1310 }
1311
1312 pm_runtime_put_noidle(&pdev->dev);
1313 pm_runtime_disable(&pdev->dev);
1314 pm_runtime_set_suspended(&pdev->dev);
1315}
1316
1317#ifdef CONFIG_PM_SLEEP
1318static int s3c64xx_spi_suspend(struct device *dev)
1319{
1320 struct spi_controller *host = dev_get_drvdata(dev);
1321 struct s3c64xx_spi_driver_data *sdd = spi_controller_get_devdata(host);
1322
1323 int ret = spi_controller_suspend(host);
1324 if (ret)
1325 return ret;
1326
1327 ret = pm_runtime_force_suspend(dev);
1328 if (ret < 0)
1329 return ret;
1330
1331 sdd->cur_speed = 0; /* Output Clock is stopped */
1332
1333 return 0;
1334}
1335
1336static int s3c64xx_spi_resume(struct device *dev)
1337{
1338 struct spi_controller *host = dev_get_drvdata(dev);
1339 struct s3c64xx_spi_driver_data *sdd = spi_controller_get_devdata(host);
1340 struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1341 int ret;
1342
1343 if (sci->cfg_gpio)
1344 sci->cfg_gpio();
1345
1346 ret = pm_runtime_force_resume(dev);
1347 if (ret < 0)
1348 return ret;
1349
1350 return spi_controller_resume(host);
1351}
1352#endif /* CONFIG_PM_SLEEP */
1353
1354#ifdef CONFIG_PM
1355static int s3c64xx_spi_runtime_suspend(struct device *dev)
1356{
1357 struct spi_controller *host = dev_get_drvdata(dev);
1358 struct s3c64xx_spi_driver_data *sdd = spi_controller_get_devdata(host);
1359
1360 clk_disable_unprepare(sdd->clk);
1361 clk_disable_unprepare(sdd->src_clk);
1362 clk_disable_unprepare(sdd->ioclk);
1363
1364 return 0;
1365}
1366
1367static int s3c64xx_spi_runtime_resume(struct device *dev)
1368{
1369 struct spi_controller *host = dev_get_drvdata(dev);
1370 struct s3c64xx_spi_driver_data *sdd = spi_controller_get_devdata(host);
1371 int ret;
1372
1373 if (sdd->port_conf->clk_ioclk) {
1374 ret = clk_prepare_enable(sdd->ioclk);
1375 if (ret != 0)
1376 return ret;
1377 }
1378
1379 ret = clk_prepare_enable(sdd->src_clk);
1380 if (ret != 0)
1381 goto err_disable_ioclk;
1382
1383 ret = clk_prepare_enable(sdd->clk);
1384 if (ret != 0)
1385 goto err_disable_src_clk;
1386
1387 s3c64xx_spi_hwinit(sdd);
1388
1389 writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
1390 S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
1391 sdd->regs + S3C64XX_SPI_INT_EN);
1392
1393 return 0;
1394
1395err_disable_src_clk:
1396 clk_disable_unprepare(sdd->src_clk);
1397err_disable_ioclk:
1398 clk_disable_unprepare(sdd->ioclk);
1399
1400 return ret;
1401}
1402#endif /* CONFIG_PM */
1403
1404static const struct dev_pm_ops s3c64xx_spi_pm = {
1405 SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume)
1406 SET_RUNTIME_PM_OPS(s3c64xx_spi_runtime_suspend,
1407 s3c64xx_spi_runtime_resume, NULL)
1408};
1409
1410static const struct s3c64xx_spi_port_config s3c2443_spi_port_config = {
1411 .fifo_lvl_mask = { 0x7f },
1412 .rx_lvl_offset = 13,
1413 .tx_st_done = 21,
1414 .clk_div = 2,
1415 .high_speed = true,
1416};
1417
1418static const struct s3c64xx_spi_port_config s3c6410_spi_port_config = {
1419 .fifo_lvl_mask = { 0x7f, 0x7F },
1420 .rx_lvl_offset = 13,
1421 .tx_st_done = 21,
1422 .clk_div = 2,
1423};
1424
1425static const struct s3c64xx_spi_port_config s5pv210_spi_port_config = {
1426 .fifo_lvl_mask = { 0x1ff, 0x7F },
1427 .rx_lvl_offset = 15,
1428 .tx_st_done = 25,
1429 .clk_div = 2,
1430 .high_speed = true,
1431};
1432
1433static const struct s3c64xx_spi_port_config exynos4_spi_port_config = {
1434 .fifo_lvl_mask = { 0x1ff, 0x7F, 0x7F },
1435 .rx_lvl_offset = 15,
1436 .tx_st_done = 25,
1437 .clk_div = 2,
1438 .high_speed = true,
1439 .clk_from_cmu = true,
1440 .quirks = S3C64XX_SPI_QUIRK_CS_AUTO,
1441};
1442
1443static const struct s3c64xx_spi_port_config exynos7_spi_port_config = {
1444 .fifo_lvl_mask = { 0x1ff, 0x7F, 0x7F, 0x7F, 0x7F, 0x1ff},
1445 .rx_lvl_offset = 15,
1446 .tx_st_done = 25,
1447 .clk_div = 2,
1448 .high_speed = true,
1449 .clk_from_cmu = true,
1450 .quirks = S3C64XX_SPI_QUIRK_CS_AUTO,
1451};
1452
1453static const struct s3c64xx_spi_port_config exynos5433_spi_port_config = {
1454 .fifo_lvl_mask = { 0x1ff, 0x7f, 0x7f, 0x7f, 0x7f, 0x1ff},
1455 .rx_lvl_offset = 15,
1456 .tx_st_done = 25,
1457 .clk_div = 2,
1458 .high_speed = true,
1459 .clk_from_cmu = true,
1460 .clk_ioclk = true,
1461 .quirks = S3C64XX_SPI_QUIRK_CS_AUTO,
1462};
1463
1464static const struct s3c64xx_spi_port_config exynosautov9_spi_port_config = {
1465 .fifo_lvl_mask = { 0x1ff, 0x1ff, 0x7f, 0x7f, 0x7f, 0x7f, 0x1ff, 0x7f,
1466 0x7f, 0x7f, 0x7f, 0x7f},
1467 .rx_lvl_offset = 15,
1468 .tx_st_done = 25,
1469 .clk_div = 4,
1470 .high_speed = true,
1471 .clk_from_cmu = true,
1472 .clk_ioclk = true,
1473 .has_loopback = true,
1474 .quirks = S3C64XX_SPI_QUIRK_CS_AUTO,
1475};
1476
1477static const struct s3c64xx_spi_port_config fsd_spi_port_config = {
1478 .fifo_lvl_mask = { 0x7f, 0x7f, 0x7f, 0x7f, 0x7f},
1479 .rx_lvl_offset = 15,
1480 .tx_st_done = 25,
1481 .clk_div = 2,
1482 .high_speed = true,
1483 .clk_from_cmu = true,
1484 .clk_ioclk = false,
1485 .quirks = S3C64XX_SPI_QUIRK_CS_AUTO,
1486};
1487
1488static const struct platform_device_id s3c64xx_spi_driver_ids[] = {
1489 {
1490 .name = "s3c2443-spi",
1491 .driver_data = (kernel_ulong_t)&s3c2443_spi_port_config,
1492 }, {
1493 .name = "s3c6410-spi",
1494 .driver_data = (kernel_ulong_t)&s3c6410_spi_port_config,
1495 },
1496 { },
1497};
1498
1499static const struct of_device_id s3c64xx_spi_dt_match[] = {
1500 { .compatible = "samsung,s3c2443-spi",
1501 .data = (void *)&s3c2443_spi_port_config,
1502 },
1503 { .compatible = "samsung,s3c6410-spi",
1504 .data = (void *)&s3c6410_spi_port_config,
1505 },
1506 { .compatible = "samsung,s5pv210-spi",
1507 .data = (void *)&s5pv210_spi_port_config,
1508 },
1509 { .compatible = "samsung,exynos4210-spi",
1510 .data = (void *)&exynos4_spi_port_config,
1511 },
1512 { .compatible = "samsung,exynos7-spi",
1513 .data = (void *)&exynos7_spi_port_config,
1514 },
1515 { .compatible = "samsung,exynos5433-spi",
1516 .data = (void *)&exynos5433_spi_port_config,
1517 },
1518 { .compatible = "samsung,exynosautov9-spi",
1519 .data = (void *)&exynosautov9_spi_port_config,
1520 },
1521 { .compatible = "tesla,fsd-spi",
1522 .data = (void *)&fsd_spi_port_config,
1523 },
1524 { },
1525};
1526MODULE_DEVICE_TABLE(of, s3c64xx_spi_dt_match);
1527
1528static struct platform_driver s3c64xx_spi_driver = {
1529 .driver = {
1530 .name = "s3c64xx-spi",
1531 .pm = &s3c64xx_spi_pm,
1532 .of_match_table = of_match_ptr(s3c64xx_spi_dt_match),
1533 },
1534 .probe = s3c64xx_spi_probe,
1535 .remove_new = s3c64xx_spi_remove,
1536 .id_table = s3c64xx_spi_driver_ids,
1537};
1538MODULE_ALIAS("platform:s3c64xx-spi");
1539
1540module_platform_driver(s3c64xx_spi_driver);
1541
1542MODULE_AUTHOR("Jaswinder Singh <jassi.brar@samsung.com>");
1543MODULE_DESCRIPTION("S3C64XX SPI Controller Driver");
1544MODULE_LICENSE("GPL");
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/platform_device.h>
28#include <linux/pm_runtime.h>
29#include <linux/spi/spi.h>
30
31#include <mach/dma.h>
32#include <plat/s3c64xx-spi.h>
33
34/* Registers and bit-fields */
35
36#define S3C64XX_SPI_CH_CFG 0x00
37#define S3C64XX_SPI_CLK_CFG 0x04
38#define S3C64XX_SPI_MODE_CFG 0x08
39#define S3C64XX_SPI_SLAVE_SEL 0x0C
40#define S3C64XX_SPI_INT_EN 0x10
41#define S3C64XX_SPI_STATUS 0x14
42#define S3C64XX_SPI_TX_DATA 0x18
43#define S3C64XX_SPI_RX_DATA 0x1C
44#define S3C64XX_SPI_PACKET_CNT 0x20
45#define S3C64XX_SPI_PENDING_CLR 0x24
46#define S3C64XX_SPI_SWAP_CFG 0x28
47#define S3C64XX_SPI_FB_CLK 0x2C
48
49#define S3C64XX_SPI_CH_HS_EN (1<<6) /* High Speed Enable */
50#define S3C64XX_SPI_CH_SW_RST (1<<5)
51#define S3C64XX_SPI_CH_SLAVE (1<<4)
52#define S3C64XX_SPI_CPOL_L (1<<3)
53#define S3C64XX_SPI_CPHA_B (1<<2)
54#define S3C64XX_SPI_CH_RXCH_ON (1<<1)
55#define S3C64XX_SPI_CH_TXCH_ON (1<<0)
56
57#define S3C64XX_SPI_CLKSEL_SRCMSK (3<<9)
58#define S3C64XX_SPI_CLKSEL_SRCSHFT 9
59#define S3C64XX_SPI_ENCLK_ENABLE (1<<8)
60#define S3C64XX_SPI_PSR_MASK 0xff
61
62#define S3C64XX_SPI_MODE_CH_TSZ_BYTE (0<<29)
63#define S3C64XX_SPI_MODE_CH_TSZ_HALFWORD (1<<29)
64#define S3C64XX_SPI_MODE_CH_TSZ_WORD (2<<29)
65#define S3C64XX_SPI_MODE_CH_TSZ_MASK (3<<29)
66#define S3C64XX_SPI_MODE_BUS_TSZ_BYTE (0<<17)
67#define S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD (1<<17)
68#define S3C64XX_SPI_MODE_BUS_TSZ_WORD (2<<17)
69#define S3C64XX_SPI_MODE_BUS_TSZ_MASK (3<<17)
70#define S3C64XX_SPI_MODE_RXDMA_ON (1<<2)
71#define S3C64XX_SPI_MODE_TXDMA_ON (1<<1)
72#define S3C64XX_SPI_MODE_4BURST (1<<0)
73
74#define S3C64XX_SPI_SLAVE_AUTO (1<<1)
75#define S3C64XX_SPI_SLAVE_SIG_INACT (1<<0)
76
77#define S3C64XX_SPI_ACT(c) writel(0, (c)->regs + S3C64XX_SPI_SLAVE_SEL)
78
79#define S3C64XX_SPI_DEACT(c) writel(S3C64XX_SPI_SLAVE_SIG_INACT, \
80 (c)->regs + S3C64XX_SPI_SLAVE_SEL)
81
82#define S3C64XX_SPI_INT_TRAILING_EN (1<<6)
83#define S3C64XX_SPI_INT_RX_OVERRUN_EN (1<<5)
84#define S3C64XX_SPI_INT_RX_UNDERRUN_EN (1<<4)
85#define S3C64XX_SPI_INT_TX_OVERRUN_EN (1<<3)
86#define S3C64XX_SPI_INT_TX_UNDERRUN_EN (1<<2)
87#define S3C64XX_SPI_INT_RX_FIFORDY_EN (1<<1)
88#define S3C64XX_SPI_INT_TX_FIFORDY_EN (1<<0)
89
90#define S3C64XX_SPI_ST_RX_OVERRUN_ERR (1<<5)
91#define S3C64XX_SPI_ST_RX_UNDERRUN_ERR (1<<4)
92#define S3C64XX_SPI_ST_TX_OVERRUN_ERR (1<<3)
93#define S3C64XX_SPI_ST_TX_UNDERRUN_ERR (1<<2)
94#define S3C64XX_SPI_ST_RX_FIFORDY (1<<1)
95#define S3C64XX_SPI_ST_TX_FIFORDY (1<<0)
96
97#define S3C64XX_SPI_PACKET_CNT_EN (1<<16)
98
99#define S3C64XX_SPI_PND_TX_UNDERRUN_CLR (1<<4)
100#define S3C64XX_SPI_PND_TX_OVERRUN_CLR (1<<3)
101#define S3C64XX_SPI_PND_RX_UNDERRUN_CLR (1<<2)
102#define S3C64XX_SPI_PND_RX_OVERRUN_CLR (1<<1)
103#define S3C64XX_SPI_PND_TRAILING_CLR (1<<0)
104
105#define S3C64XX_SPI_SWAP_RX_HALF_WORD (1<<7)
106#define S3C64XX_SPI_SWAP_RX_BYTE (1<<6)
107#define S3C64XX_SPI_SWAP_RX_BIT (1<<5)
108#define S3C64XX_SPI_SWAP_RX_EN (1<<4)
109#define S3C64XX_SPI_SWAP_TX_HALF_WORD (1<<3)
110#define S3C64XX_SPI_SWAP_TX_BYTE (1<<2)
111#define S3C64XX_SPI_SWAP_TX_BIT (1<<1)
112#define S3C64XX_SPI_SWAP_TX_EN (1<<0)
113
114#define S3C64XX_SPI_FBCLK_MSK (3<<0)
115
116#define S3C64XX_SPI_ST_TRLCNTZ(v, i) ((((v) >> (i)->rx_lvl_offset) & \
117 (((i)->fifo_lvl_mask + 1))) \
118 ? 1 : 0)
119
120#define S3C64XX_SPI_ST_TX_DONE(v, i) (((v) & (1 << (i)->tx_st_done)) ? 1 : 0)
121#define TX_FIFO_LVL(v, i) (((v) >> 6) & (i)->fifo_lvl_mask)
122#define RX_FIFO_LVL(v, i) (((v) >> (i)->rx_lvl_offset) & (i)->fifo_lvl_mask)
123
124#define S3C64XX_SPI_MAX_TRAILCNT 0x3ff
125#define S3C64XX_SPI_TRAILCNT_OFF 19
126
127#define S3C64XX_SPI_TRAILCNT S3C64XX_SPI_MAX_TRAILCNT
128
129#define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
130
131#define RXBUSY (1<<2)
132#define TXBUSY (1<<3)
133
134struct s3c64xx_spi_dma_data {
135 unsigned ch;
136 enum dma_data_direction direction;
137 enum dma_ch dmach;
138};
139
140/**
141 * struct s3c64xx_spi_driver_data - Runtime info holder for SPI driver.
142 * @clk: Pointer to the spi clock.
143 * @src_clk: Pointer to the clock used to generate SPI signals.
144 * @master: Pointer to the SPI Protocol master.
145 * @cntrlr_info: Platform specific data for the controller this driver manages.
146 * @tgl_spi: Pointer to the last CS left untoggled by the cs_change hint.
147 * @queue: To log SPI xfer requests.
148 * @lock: Controller specific lock.
149 * @state: Set of FLAGS to indicate status.
150 * @rx_dmach: Controller's DMA channel for Rx.
151 * @tx_dmach: Controller's DMA channel for Tx.
152 * @sfr_start: BUS address of SPI controller regs.
153 * @regs: Pointer to ioremap'ed controller registers.
154 * @irq: interrupt
155 * @xfer_completion: To indicate completion of xfer task.
156 * @cur_mode: Stores the active configuration of the controller.
157 * @cur_bpw: Stores the active bits per word settings.
158 * @cur_speed: Stores the active xfer clock speed.
159 */
160struct s3c64xx_spi_driver_data {
161 void __iomem *regs;
162 struct clk *clk;
163 struct clk *src_clk;
164 struct platform_device *pdev;
165 struct spi_master *master;
166 struct s3c64xx_spi_info *cntrlr_info;
167 struct spi_device *tgl_spi;
168 struct list_head queue;
169 spinlock_t lock;
170 unsigned long sfr_start;
171 struct completion xfer_completion;
172 unsigned state;
173 unsigned cur_mode, cur_bpw;
174 unsigned cur_speed;
175 struct s3c64xx_spi_dma_data rx_dma;
176 struct s3c64xx_spi_dma_data tx_dma;
177 struct samsung_dma_ops *ops;
178};
179
180static struct s3c2410_dma_client s3c64xx_spi_dma_client = {
181 .name = "samsung-spi-dma",
182};
183
184static void flush_fifo(struct s3c64xx_spi_driver_data *sdd)
185{
186 struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
187 void __iomem *regs = sdd->regs;
188 unsigned long loops;
189 u32 val;
190
191 writel(0, regs + S3C64XX_SPI_PACKET_CNT);
192
193 val = readl(regs + S3C64XX_SPI_CH_CFG);
194 val |= S3C64XX_SPI_CH_SW_RST;
195 val &= ~S3C64XX_SPI_CH_HS_EN;
196 writel(val, regs + S3C64XX_SPI_CH_CFG);
197
198 /* Flush TxFIFO*/
199 loops = msecs_to_loops(1);
200 do {
201 val = readl(regs + S3C64XX_SPI_STATUS);
202 } while (TX_FIFO_LVL(val, sci) && loops--);
203
204 if (loops == 0)
205 dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n");
206
207 /* Flush RxFIFO*/
208 loops = msecs_to_loops(1);
209 do {
210 val = readl(regs + S3C64XX_SPI_STATUS);
211 if (RX_FIFO_LVL(val, sci))
212 readl(regs + S3C64XX_SPI_RX_DATA);
213 else
214 break;
215 } while (loops--);
216
217 if (loops == 0)
218 dev_warn(&sdd->pdev->dev, "Timed out flushing RX FIFO\n");
219
220 val = readl(regs + S3C64XX_SPI_CH_CFG);
221 val &= ~S3C64XX_SPI_CH_SW_RST;
222 writel(val, regs + S3C64XX_SPI_CH_CFG);
223
224 val = readl(regs + S3C64XX_SPI_MODE_CFG);
225 val &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
226 writel(val, regs + S3C64XX_SPI_MODE_CFG);
227
228 val = readl(regs + S3C64XX_SPI_CH_CFG);
229 val &= ~(S3C64XX_SPI_CH_RXCH_ON | S3C64XX_SPI_CH_TXCH_ON);
230 writel(val, regs + S3C64XX_SPI_CH_CFG);
231}
232
233static void s3c64xx_spi_dmacb(void *data)
234{
235 struct s3c64xx_spi_driver_data *sdd;
236 struct s3c64xx_spi_dma_data *dma = data;
237 unsigned long flags;
238
239 if (dma->direction == DMA_DEV_TO_MEM)
240 sdd = container_of(data,
241 struct s3c64xx_spi_driver_data, rx_dma);
242 else
243 sdd = container_of(data,
244 struct s3c64xx_spi_driver_data, tx_dma);
245
246 spin_lock_irqsave(&sdd->lock, flags);
247
248 if (dma->direction == DMA_DEV_TO_MEM) {
249 sdd->state &= ~RXBUSY;
250 if (!(sdd->state & TXBUSY))
251 complete(&sdd->xfer_completion);
252 } else {
253 sdd->state &= ~TXBUSY;
254 if (!(sdd->state & RXBUSY))
255 complete(&sdd->xfer_completion);
256 }
257
258 spin_unlock_irqrestore(&sdd->lock, flags);
259}
260
261static void prepare_dma(struct s3c64xx_spi_dma_data *dma,
262 unsigned len, dma_addr_t buf)
263{
264 struct s3c64xx_spi_driver_data *sdd;
265 struct samsung_dma_prep_info info;
266
267 if (dma->direction == DMA_DEV_TO_MEM)
268 sdd = container_of((void *)dma,
269 struct s3c64xx_spi_driver_data, rx_dma);
270 else
271 sdd = container_of((void *)dma,
272 struct s3c64xx_spi_driver_data, tx_dma);
273
274 info.cap = DMA_SLAVE;
275 info.len = len;
276 info.fp = s3c64xx_spi_dmacb;
277 info.fp_param = dma;
278 info.direction = dma->direction;
279 info.buf = buf;
280
281 sdd->ops->prepare(dma->ch, &info);
282 sdd->ops->trigger(dma->ch);
283}
284
285static int acquire_dma(struct s3c64xx_spi_driver_data *sdd)
286{
287 struct samsung_dma_info info;
288
289 sdd->ops = samsung_dma_get_ops();
290
291 info.cap = DMA_SLAVE;
292 info.client = &s3c64xx_spi_dma_client;
293 info.width = sdd->cur_bpw / 8;
294
295 info.direction = sdd->rx_dma.direction;
296 info.fifo = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
297 sdd->rx_dma.ch = sdd->ops->request(sdd->rx_dma.dmach, &info);
298 info.direction = sdd->tx_dma.direction;
299 info.fifo = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
300 sdd->tx_dma.ch = sdd->ops->request(sdd->tx_dma.dmach, &info);
301
302 return 1;
303}
304
305static void enable_datapath(struct s3c64xx_spi_driver_data *sdd,
306 struct spi_device *spi,
307 struct spi_transfer *xfer, int dma_mode)
308{
309 struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
310 void __iomem *regs = sdd->regs;
311 u32 modecfg, chcfg;
312
313 modecfg = readl(regs + S3C64XX_SPI_MODE_CFG);
314 modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
315
316 chcfg = readl(regs + S3C64XX_SPI_CH_CFG);
317 chcfg &= ~S3C64XX_SPI_CH_TXCH_ON;
318
319 if (dma_mode) {
320 chcfg &= ~S3C64XX_SPI_CH_RXCH_ON;
321 } else {
322 /* Always shift in data in FIFO, even if xfer is Tx only,
323 * this helps setting PCKT_CNT value for generating clocks
324 * as exactly needed.
325 */
326 chcfg |= S3C64XX_SPI_CH_RXCH_ON;
327 writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
328 | S3C64XX_SPI_PACKET_CNT_EN,
329 regs + S3C64XX_SPI_PACKET_CNT);
330 }
331
332 if (xfer->tx_buf != NULL) {
333 sdd->state |= TXBUSY;
334 chcfg |= S3C64XX_SPI_CH_TXCH_ON;
335 if (dma_mode) {
336 modecfg |= S3C64XX_SPI_MODE_TXDMA_ON;
337 prepare_dma(&sdd->tx_dma, xfer->len, xfer->tx_dma);
338 } else {
339 switch (sdd->cur_bpw) {
340 case 32:
341 iowrite32_rep(regs + S3C64XX_SPI_TX_DATA,
342 xfer->tx_buf, xfer->len / 4);
343 break;
344 case 16:
345 iowrite16_rep(regs + S3C64XX_SPI_TX_DATA,
346 xfer->tx_buf, xfer->len / 2);
347 break;
348 default:
349 iowrite8_rep(regs + S3C64XX_SPI_TX_DATA,
350 xfer->tx_buf, xfer->len);
351 break;
352 }
353 }
354 }
355
356 if (xfer->rx_buf != NULL) {
357 sdd->state |= RXBUSY;
358
359 if (sci->high_speed && sdd->cur_speed >= 30000000UL
360 && !(sdd->cur_mode & SPI_CPHA))
361 chcfg |= S3C64XX_SPI_CH_HS_EN;
362
363 if (dma_mode) {
364 modecfg |= S3C64XX_SPI_MODE_RXDMA_ON;
365 chcfg |= S3C64XX_SPI_CH_RXCH_ON;
366 writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
367 | S3C64XX_SPI_PACKET_CNT_EN,
368 regs + S3C64XX_SPI_PACKET_CNT);
369 prepare_dma(&sdd->rx_dma, xfer->len, xfer->rx_dma);
370 }
371 }
372
373 writel(modecfg, regs + S3C64XX_SPI_MODE_CFG);
374 writel(chcfg, regs + S3C64XX_SPI_CH_CFG);
375}
376
377static inline void enable_cs(struct s3c64xx_spi_driver_data *sdd,
378 struct spi_device *spi)
379{
380 struct s3c64xx_spi_csinfo *cs;
381
382 if (sdd->tgl_spi != NULL) { /* If last device toggled after mssg */
383 if (sdd->tgl_spi != spi) { /* if last mssg on diff device */
384 /* Deselect the last toggled device */
385 cs = sdd->tgl_spi->controller_data;
386 cs->set_level(cs->line,
387 spi->mode & SPI_CS_HIGH ? 0 : 1);
388 }
389 sdd->tgl_spi = NULL;
390 }
391
392 cs = spi->controller_data;
393 cs->set_level(cs->line, spi->mode & SPI_CS_HIGH ? 1 : 0);
394}
395
396static int wait_for_xfer(struct s3c64xx_spi_driver_data *sdd,
397 struct spi_transfer *xfer, int dma_mode)
398{
399 struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
400 void __iomem *regs = sdd->regs;
401 unsigned long val;
402 int ms;
403
404 /* millisecs to xfer 'len' bytes @ 'cur_speed' */
405 ms = xfer->len * 8 * 1000 / sdd->cur_speed;
406 ms += 10; /* some tolerance */
407
408 if (dma_mode) {
409 val = msecs_to_jiffies(ms) + 10;
410 val = wait_for_completion_timeout(&sdd->xfer_completion, val);
411 } else {
412 u32 status;
413 val = msecs_to_loops(ms);
414 do {
415 status = readl(regs + S3C64XX_SPI_STATUS);
416 } while (RX_FIFO_LVL(status, sci) < xfer->len && --val);
417 }
418
419 if (!val)
420 return -EIO;
421
422 if (dma_mode) {
423 u32 status;
424
425 /*
426 * DmaTx returns after simply writing data in the FIFO,
427 * w/o waiting for real transmission on the bus to finish.
428 * DmaRx returns only after Dma read data from FIFO which
429 * needs bus transmission to finish, so we don't worry if
430 * Xfer involved Rx(with or without Tx).
431 */
432 if (xfer->rx_buf == NULL) {
433 val = msecs_to_loops(10);
434 status = readl(regs + S3C64XX_SPI_STATUS);
435 while ((TX_FIFO_LVL(status, sci)
436 || !S3C64XX_SPI_ST_TX_DONE(status, sci))
437 && --val) {
438 cpu_relax();
439 status = readl(regs + S3C64XX_SPI_STATUS);
440 }
441
442 if (!val)
443 return -EIO;
444 }
445 } else {
446 /* If it was only Tx */
447 if (xfer->rx_buf == NULL) {
448 sdd->state &= ~TXBUSY;
449 return 0;
450 }
451
452 switch (sdd->cur_bpw) {
453 case 32:
454 ioread32_rep(regs + S3C64XX_SPI_RX_DATA,
455 xfer->rx_buf, xfer->len / 4);
456 break;
457 case 16:
458 ioread16_rep(regs + S3C64XX_SPI_RX_DATA,
459 xfer->rx_buf, xfer->len / 2);
460 break;
461 default:
462 ioread8_rep(regs + S3C64XX_SPI_RX_DATA,
463 xfer->rx_buf, xfer->len);
464 break;
465 }
466 sdd->state &= ~RXBUSY;
467 }
468
469 return 0;
470}
471
472static inline void disable_cs(struct s3c64xx_spi_driver_data *sdd,
473 struct spi_device *spi)
474{
475 struct s3c64xx_spi_csinfo *cs = spi->controller_data;
476
477 if (sdd->tgl_spi == spi)
478 sdd->tgl_spi = NULL;
479
480 cs->set_level(cs->line, spi->mode & SPI_CS_HIGH ? 0 : 1);
481}
482
483static void s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
484{
485 struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
486 void __iomem *regs = sdd->regs;
487 u32 val;
488
489 /* Disable Clock */
490 if (sci->clk_from_cmu) {
491 clk_disable(sdd->src_clk);
492 } else {
493 val = readl(regs + S3C64XX_SPI_CLK_CFG);
494 val &= ~S3C64XX_SPI_ENCLK_ENABLE;
495 writel(val, regs + S3C64XX_SPI_CLK_CFG);
496 }
497
498 /* Set Polarity and Phase */
499 val = readl(regs + S3C64XX_SPI_CH_CFG);
500 val &= ~(S3C64XX_SPI_CH_SLAVE |
501 S3C64XX_SPI_CPOL_L |
502 S3C64XX_SPI_CPHA_B);
503
504 if (sdd->cur_mode & SPI_CPOL)
505 val |= S3C64XX_SPI_CPOL_L;
506
507 if (sdd->cur_mode & SPI_CPHA)
508 val |= S3C64XX_SPI_CPHA_B;
509
510 writel(val, regs + S3C64XX_SPI_CH_CFG);
511
512 /* Set Channel & DMA Mode */
513 val = readl(regs + S3C64XX_SPI_MODE_CFG);
514 val &= ~(S3C64XX_SPI_MODE_BUS_TSZ_MASK
515 | S3C64XX_SPI_MODE_CH_TSZ_MASK);
516
517 switch (sdd->cur_bpw) {
518 case 32:
519 val |= S3C64XX_SPI_MODE_BUS_TSZ_WORD;
520 val |= S3C64XX_SPI_MODE_CH_TSZ_WORD;
521 break;
522 case 16:
523 val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD;
524 val |= S3C64XX_SPI_MODE_CH_TSZ_HALFWORD;
525 break;
526 default:
527 val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE;
528 val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE;
529 break;
530 }
531
532 writel(val, regs + S3C64XX_SPI_MODE_CFG);
533
534 if (sci->clk_from_cmu) {
535 /* Configure Clock */
536 /* There is half-multiplier before the SPI */
537 clk_set_rate(sdd->src_clk, sdd->cur_speed * 2);
538 /* Enable Clock */
539 clk_enable(sdd->src_clk);
540 } else {
541 /* Configure Clock */
542 val = readl(regs + S3C64XX_SPI_CLK_CFG);
543 val &= ~S3C64XX_SPI_PSR_MASK;
544 val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / 2 - 1)
545 & S3C64XX_SPI_PSR_MASK);
546 writel(val, regs + S3C64XX_SPI_CLK_CFG);
547
548 /* Enable Clock */
549 val = readl(regs + S3C64XX_SPI_CLK_CFG);
550 val |= S3C64XX_SPI_ENCLK_ENABLE;
551 writel(val, regs + S3C64XX_SPI_CLK_CFG);
552 }
553}
554
555#define XFER_DMAADDR_INVALID DMA_BIT_MASK(32)
556
557static int s3c64xx_spi_map_mssg(struct s3c64xx_spi_driver_data *sdd,
558 struct spi_message *msg)
559{
560 struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
561 struct device *dev = &sdd->pdev->dev;
562 struct spi_transfer *xfer;
563
564 if (msg->is_dma_mapped)
565 return 0;
566
567 /* First mark all xfer unmapped */
568 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
569 xfer->rx_dma = XFER_DMAADDR_INVALID;
570 xfer->tx_dma = XFER_DMAADDR_INVALID;
571 }
572
573 /* Map until end or first fail */
574 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
575
576 if (xfer->len <= ((sci->fifo_lvl_mask >> 1) + 1))
577 continue;
578
579 if (xfer->tx_buf != NULL) {
580 xfer->tx_dma = dma_map_single(dev,
581 (void *)xfer->tx_buf, xfer->len,
582 DMA_TO_DEVICE);
583 if (dma_mapping_error(dev, xfer->tx_dma)) {
584 dev_err(dev, "dma_map_single Tx failed\n");
585 xfer->tx_dma = XFER_DMAADDR_INVALID;
586 return -ENOMEM;
587 }
588 }
589
590 if (xfer->rx_buf != NULL) {
591 xfer->rx_dma = dma_map_single(dev, xfer->rx_buf,
592 xfer->len, DMA_FROM_DEVICE);
593 if (dma_mapping_error(dev, xfer->rx_dma)) {
594 dev_err(dev, "dma_map_single Rx failed\n");
595 dma_unmap_single(dev, xfer->tx_dma,
596 xfer->len, DMA_TO_DEVICE);
597 xfer->tx_dma = XFER_DMAADDR_INVALID;
598 xfer->rx_dma = XFER_DMAADDR_INVALID;
599 return -ENOMEM;
600 }
601 }
602 }
603
604 return 0;
605}
606
607static void s3c64xx_spi_unmap_mssg(struct s3c64xx_spi_driver_data *sdd,
608 struct spi_message *msg)
609{
610 struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
611 struct device *dev = &sdd->pdev->dev;
612 struct spi_transfer *xfer;
613
614 if (msg->is_dma_mapped)
615 return;
616
617 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
618
619 if (xfer->len <= ((sci->fifo_lvl_mask >> 1) + 1))
620 continue;
621
622 if (xfer->rx_buf != NULL
623 && xfer->rx_dma != XFER_DMAADDR_INVALID)
624 dma_unmap_single(dev, xfer->rx_dma,
625 xfer->len, DMA_FROM_DEVICE);
626
627 if (xfer->tx_buf != NULL
628 && xfer->tx_dma != XFER_DMAADDR_INVALID)
629 dma_unmap_single(dev, xfer->tx_dma,
630 xfer->len, DMA_TO_DEVICE);
631 }
632}
633
634static int s3c64xx_spi_transfer_one_message(struct spi_master *master,
635 struct spi_message *msg)
636{
637 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
638 struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
639 struct spi_device *spi = msg->spi;
640 struct s3c64xx_spi_csinfo *cs = spi->controller_data;
641 struct spi_transfer *xfer;
642 int status = 0, cs_toggle = 0;
643 u32 speed;
644 u8 bpw;
645
646 /* If Master's(controller) state differs from that needed by Slave */
647 if (sdd->cur_speed != spi->max_speed_hz
648 || sdd->cur_mode != spi->mode
649 || sdd->cur_bpw != spi->bits_per_word) {
650 sdd->cur_bpw = spi->bits_per_word;
651 sdd->cur_speed = spi->max_speed_hz;
652 sdd->cur_mode = spi->mode;
653 s3c64xx_spi_config(sdd);
654 }
655
656 /* Map all the transfers if needed */
657 if (s3c64xx_spi_map_mssg(sdd, msg)) {
658 dev_err(&spi->dev,
659 "Xfer: Unable to map message buffers!\n");
660 status = -ENOMEM;
661 goto out;
662 }
663
664 /* Configure feedback delay */
665 writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK);
666
667 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
668
669 unsigned long flags;
670 int use_dma;
671
672 INIT_COMPLETION(sdd->xfer_completion);
673
674 /* Only BPW and Speed may change across transfers */
675 bpw = xfer->bits_per_word ? : spi->bits_per_word;
676 speed = xfer->speed_hz ? : spi->max_speed_hz;
677
678 if (xfer->len % (bpw / 8)) {
679 dev_err(&spi->dev,
680 "Xfer length(%u) not a multiple of word size(%u)\n",
681 xfer->len, bpw / 8);
682 status = -EIO;
683 goto out;
684 }
685
686 if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) {
687 sdd->cur_bpw = bpw;
688 sdd->cur_speed = speed;
689 s3c64xx_spi_config(sdd);
690 }
691
692 /* Polling method for xfers not bigger than FIFO capacity */
693 if (xfer->len <= ((sci->fifo_lvl_mask >> 1) + 1))
694 use_dma = 0;
695 else
696 use_dma = 1;
697
698 spin_lock_irqsave(&sdd->lock, flags);
699
700 /* Pending only which is to be done */
701 sdd->state &= ~RXBUSY;
702 sdd->state &= ~TXBUSY;
703
704 enable_datapath(sdd, spi, xfer, use_dma);
705
706 /* Slave Select */
707 enable_cs(sdd, spi);
708
709 /* Start the signals */
710 S3C64XX_SPI_ACT(sdd);
711
712 spin_unlock_irqrestore(&sdd->lock, flags);
713
714 status = wait_for_xfer(sdd, xfer, use_dma);
715
716 /* Quiese the signals */
717 S3C64XX_SPI_DEACT(sdd);
718
719 if (status) {
720 dev_err(&spi->dev, "I/O Error: "
721 "rx-%d tx-%d res:rx-%c tx-%c len-%d\n",
722 xfer->rx_buf ? 1 : 0, xfer->tx_buf ? 1 : 0,
723 (sdd->state & RXBUSY) ? 'f' : 'p',
724 (sdd->state & TXBUSY) ? 'f' : 'p',
725 xfer->len);
726
727 if (use_dma) {
728 if (xfer->tx_buf != NULL
729 && (sdd->state & TXBUSY))
730 sdd->ops->stop(sdd->tx_dma.ch);
731 if (xfer->rx_buf != NULL
732 && (sdd->state & RXBUSY))
733 sdd->ops->stop(sdd->rx_dma.ch);
734 }
735
736 goto out;
737 }
738
739 if (xfer->delay_usecs)
740 udelay(xfer->delay_usecs);
741
742 if (xfer->cs_change) {
743 /* Hint that the next mssg is gonna be
744 for the same device */
745 if (list_is_last(&xfer->transfer_list,
746 &msg->transfers))
747 cs_toggle = 1;
748 else
749 disable_cs(sdd, spi);
750 }
751
752 msg->actual_length += xfer->len;
753
754 flush_fifo(sdd);
755 }
756
757out:
758 if (!cs_toggle || status)
759 disable_cs(sdd, spi);
760 else
761 sdd->tgl_spi = spi;
762
763 s3c64xx_spi_unmap_mssg(sdd, msg);
764
765 msg->status = status;
766
767 spi_finalize_current_message(master);
768
769 return 0;
770}
771
772static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
773{
774 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
775
776 /* Acquire DMA channels */
777 while (!acquire_dma(sdd))
778 msleep(10);
779
780 pm_runtime_get_sync(&sdd->pdev->dev);
781
782 return 0;
783}
784
785static int s3c64xx_spi_unprepare_transfer(struct spi_master *spi)
786{
787 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
788
789 /* Free DMA channels */
790 sdd->ops->release(sdd->rx_dma.ch, &s3c64xx_spi_dma_client);
791 sdd->ops->release(sdd->tx_dma.ch, &s3c64xx_spi_dma_client);
792
793 pm_runtime_put(&sdd->pdev->dev);
794
795 return 0;
796}
797
798/*
799 * Here we only check the validity of requested configuration
800 * and save the configuration in a local data-structure.
801 * The controller is actually configured only just before we
802 * get a message to transfer.
803 */
804static int s3c64xx_spi_setup(struct spi_device *spi)
805{
806 struct s3c64xx_spi_csinfo *cs = spi->controller_data;
807 struct s3c64xx_spi_driver_data *sdd;
808 struct s3c64xx_spi_info *sci;
809 struct spi_message *msg;
810 unsigned long flags;
811 int err = 0;
812
813 if (cs == NULL || cs->set_level == NULL) {
814 dev_err(&spi->dev, "No CS for SPI(%d)\n", spi->chip_select);
815 return -ENODEV;
816 }
817
818 sdd = spi_master_get_devdata(spi->master);
819 sci = sdd->cntrlr_info;
820
821 spin_lock_irqsave(&sdd->lock, flags);
822
823 list_for_each_entry(msg, &sdd->queue, queue) {
824 /* Is some mssg is already queued for this device */
825 if (msg->spi == spi) {
826 dev_err(&spi->dev,
827 "setup: attempt while mssg in queue!\n");
828 spin_unlock_irqrestore(&sdd->lock, flags);
829 return -EBUSY;
830 }
831 }
832
833 spin_unlock_irqrestore(&sdd->lock, flags);
834
835 if (spi->bits_per_word != 8
836 && spi->bits_per_word != 16
837 && spi->bits_per_word != 32) {
838 dev_err(&spi->dev, "setup: %dbits/wrd not supported!\n",
839 spi->bits_per_word);
840 err = -EINVAL;
841 goto setup_exit;
842 }
843
844 pm_runtime_get_sync(&sdd->pdev->dev);
845
846 /* Check if we can provide the requested rate */
847 if (!sci->clk_from_cmu) {
848 u32 psr, speed;
849
850 /* Max possible */
851 speed = clk_get_rate(sdd->src_clk) / 2 / (0 + 1);
852
853 if (spi->max_speed_hz > speed)
854 spi->max_speed_hz = speed;
855
856 psr = clk_get_rate(sdd->src_clk) / 2 / spi->max_speed_hz - 1;
857 psr &= S3C64XX_SPI_PSR_MASK;
858 if (psr == S3C64XX_SPI_PSR_MASK)
859 psr--;
860
861 speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
862 if (spi->max_speed_hz < speed) {
863 if (psr+1 < S3C64XX_SPI_PSR_MASK) {
864 psr++;
865 } else {
866 err = -EINVAL;
867 goto setup_exit;
868 }
869 }
870
871 speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
872 if (spi->max_speed_hz >= speed)
873 spi->max_speed_hz = speed;
874 else
875 err = -EINVAL;
876 }
877
878 pm_runtime_put(&sdd->pdev->dev);
879
880setup_exit:
881
882 /* setup() returns with device de-selected */
883 disable_cs(sdd, spi);
884
885 return err;
886}
887
888static irqreturn_t s3c64xx_spi_irq(int irq, void *data)
889{
890 struct s3c64xx_spi_driver_data *sdd = data;
891 struct spi_master *spi = sdd->master;
892 unsigned int val;
893
894 val = readl(sdd->regs + S3C64XX_SPI_PENDING_CLR);
895
896 val &= S3C64XX_SPI_PND_RX_OVERRUN_CLR |
897 S3C64XX_SPI_PND_RX_UNDERRUN_CLR |
898 S3C64XX_SPI_PND_TX_OVERRUN_CLR |
899 S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
900
901 writel(val, sdd->regs + S3C64XX_SPI_PENDING_CLR);
902
903 if (val & S3C64XX_SPI_PND_RX_OVERRUN_CLR)
904 dev_err(&spi->dev, "RX overrun\n");
905 if (val & S3C64XX_SPI_PND_RX_UNDERRUN_CLR)
906 dev_err(&spi->dev, "RX underrun\n");
907 if (val & S3C64XX_SPI_PND_TX_OVERRUN_CLR)
908 dev_err(&spi->dev, "TX overrun\n");
909 if (val & S3C64XX_SPI_PND_TX_UNDERRUN_CLR)
910 dev_err(&spi->dev, "TX underrun\n");
911
912 return IRQ_HANDLED;
913}
914
915static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd, int channel)
916{
917 struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
918 void __iomem *regs = sdd->regs;
919 unsigned int val;
920
921 sdd->cur_speed = 0;
922
923 S3C64XX_SPI_DEACT(sdd);
924
925 /* Disable Interrupts - we use Polling if not DMA mode */
926 writel(0, regs + S3C64XX_SPI_INT_EN);
927
928 if (!sci->clk_from_cmu)
929 writel(sci->src_clk_nr << S3C64XX_SPI_CLKSEL_SRCSHFT,
930 regs + S3C64XX_SPI_CLK_CFG);
931 writel(0, regs + S3C64XX_SPI_MODE_CFG);
932 writel(0, regs + S3C64XX_SPI_PACKET_CNT);
933
934 /* Clear any irq pending bits */
935 writel(readl(regs + S3C64XX_SPI_PENDING_CLR),
936 regs + S3C64XX_SPI_PENDING_CLR);
937
938 writel(0, regs + S3C64XX_SPI_SWAP_CFG);
939
940 val = readl(regs + S3C64XX_SPI_MODE_CFG);
941 val &= ~S3C64XX_SPI_MODE_4BURST;
942 val &= ~(S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
943 val |= (S3C64XX_SPI_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
944 writel(val, regs + S3C64XX_SPI_MODE_CFG);
945
946 flush_fifo(sdd);
947}
948
949static int __init s3c64xx_spi_probe(struct platform_device *pdev)
950{
951 struct resource *mem_res, *dmatx_res, *dmarx_res;
952 struct s3c64xx_spi_driver_data *sdd;
953 struct s3c64xx_spi_info *sci;
954 struct spi_master *master;
955 int ret, irq;
956 char clk_name[16];
957
958 if (pdev->id < 0) {
959 dev_err(&pdev->dev,
960 "Invalid platform device id-%d\n", pdev->id);
961 return -ENODEV;
962 }
963
964 if (pdev->dev.platform_data == NULL) {
965 dev_err(&pdev->dev, "platform_data missing!\n");
966 return -ENODEV;
967 }
968
969 sci = pdev->dev.platform_data;
970
971 /* Check for availability of necessary resource */
972
973 dmatx_res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
974 if (dmatx_res == NULL) {
975 dev_err(&pdev->dev, "Unable to get SPI-Tx dma resource\n");
976 return -ENXIO;
977 }
978
979 dmarx_res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
980 if (dmarx_res == NULL) {
981 dev_err(&pdev->dev, "Unable to get SPI-Rx dma resource\n");
982 return -ENXIO;
983 }
984
985 mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
986 if (mem_res == NULL) {
987 dev_err(&pdev->dev, "Unable to get SPI MEM resource\n");
988 return -ENXIO;
989 }
990
991 irq = platform_get_irq(pdev, 0);
992 if (irq < 0) {
993 dev_warn(&pdev->dev, "Failed to get IRQ: %d\n", irq);
994 return irq;
995 }
996
997 master = spi_alloc_master(&pdev->dev,
998 sizeof(struct s3c64xx_spi_driver_data));
999 if (master == NULL) {
1000 dev_err(&pdev->dev, "Unable to allocate SPI Master\n");
1001 return -ENOMEM;
1002 }
1003
1004 platform_set_drvdata(pdev, master);
1005
1006 sdd = spi_master_get_devdata(master);
1007 sdd->master = master;
1008 sdd->cntrlr_info = sci;
1009 sdd->pdev = pdev;
1010 sdd->sfr_start = mem_res->start;
1011 sdd->tx_dma.dmach = dmatx_res->start;
1012 sdd->tx_dma.direction = DMA_MEM_TO_DEV;
1013 sdd->rx_dma.dmach = dmarx_res->start;
1014 sdd->rx_dma.direction = DMA_DEV_TO_MEM;
1015
1016 sdd->cur_bpw = 8;
1017
1018 master->bus_num = pdev->id;
1019 master->setup = s3c64xx_spi_setup;
1020 master->prepare_transfer_hardware = s3c64xx_spi_prepare_transfer;
1021 master->transfer_one_message = s3c64xx_spi_transfer_one_message;
1022 master->unprepare_transfer_hardware = s3c64xx_spi_unprepare_transfer;
1023 master->num_chipselect = sci->num_cs;
1024 master->dma_alignment = 8;
1025 /* the spi->mode bits understood by this driver: */
1026 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1027
1028 if (request_mem_region(mem_res->start,
1029 resource_size(mem_res), pdev->name) == NULL) {
1030 dev_err(&pdev->dev, "Req mem region failed\n");
1031 ret = -ENXIO;
1032 goto err0;
1033 }
1034
1035 sdd->regs = ioremap(mem_res->start, resource_size(mem_res));
1036 if (sdd->regs == NULL) {
1037 dev_err(&pdev->dev, "Unable to remap IO\n");
1038 ret = -ENXIO;
1039 goto err1;
1040 }
1041
1042 if (sci->cfg_gpio == NULL || sci->cfg_gpio(pdev)) {
1043 dev_err(&pdev->dev, "Unable to config gpio\n");
1044 ret = -EBUSY;
1045 goto err2;
1046 }
1047
1048 /* Setup clocks */
1049 sdd->clk = clk_get(&pdev->dev, "spi");
1050 if (IS_ERR(sdd->clk)) {
1051 dev_err(&pdev->dev, "Unable to acquire clock 'spi'\n");
1052 ret = PTR_ERR(sdd->clk);
1053 goto err3;
1054 }
1055
1056 if (clk_enable(sdd->clk)) {
1057 dev_err(&pdev->dev, "Couldn't enable clock 'spi'\n");
1058 ret = -EBUSY;
1059 goto err4;
1060 }
1061
1062 sprintf(clk_name, "spi_busclk%d", sci->src_clk_nr);
1063 sdd->src_clk = clk_get(&pdev->dev, clk_name);
1064 if (IS_ERR(sdd->src_clk)) {
1065 dev_err(&pdev->dev,
1066 "Unable to acquire clock '%s'\n", clk_name);
1067 ret = PTR_ERR(sdd->src_clk);
1068 goto err5;
1069 }
1070
1071 if (clk_enable(sdd->src_clk)) {
1072 dev_err(&pdev->dev, "Couldn't enable clock '%s'\n", clk_name);
1073 ret = -EBUSY;
1074 goto err6;
1075 }
1076
1077 /* Setup Deufult Mode */
1078 s3c64xx_spi_hwinit(sdd, pdev->id);
1079
1080 spin_lock_init(&sdd->lock);
1081 init_completion(&sdd->xfer_completion);
1082 INIT_LIST_HEAD(&sdd->queue);
1083
1084 ret = request_irq(irq, s3c64xx_spi_irq, 0, "spi-s3c64xx", sdd);
1085 if (ret != 0) {
1086 dev_err(&pdev->dev, "Failed to request IRQ %d: %d\n",
1087 irq, ret);
1088 goto err7;
1089 }
1090
1091 writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
1092 S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
1093 sdd->regs + S3C64XX_SPI_INT_EN);
1094
1095 if (spi_register_master(master)) {
1096 dev_err(&pdev->dev, "cannot register SPI master\n");
1097 ret = -EBUSY;
1098 goto err8;
1099 }
1100
1101 dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d "
1102 "with %d Slaves attached\n",
1103 pdev->id, master->num_chipselect);
1104 dev_dbg(&pdev->dev, "\tIOmem=[0x%x-0x%x]\tDMA=[Rx-%d, Tx-%d]\n",
1105 mem_res->end, mem_res->start,
1106 sdd->rx_dma.dmach, sdd->tx_dma.dmach);
1107
1108 pm_runtime_enable(&pdev->dev);
1109
1110 return 0;
1111
1112err8:
1113 free_irq(irq, sdd);
1114err7:
1115 clk_disable(sdd->src_clk);
1116err6:
1117 clk_put(sdd->src_clk);
1118err5:
1119 clk_disable(sdd->clk);
1120err4:
1121 clk_put(sdd->clk);
1122err3:
1123err2:
1124 iounmap((void *) sdd->regs);
1125err1:
1126 release_mem_region(mem_res->start, resource_size(mem_res));
1127err0:
1128 platform_set_drvdata(pdev, NULL);
1129 spi_master_put(master);
1130
1131 return ret;
1132}
1133
1134static int s3c64xx_spi_remove(struct platform_device *pdev)
1135{
1136 struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
1137 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1138 struct resource *mem_res;
1139
1140 pm_runtime_disable(&pdev->dev);
1141
1142 spi_unregister_master(master);
1143
1144 writel(0, sdd->regs + S3C64XX_SPI_INT_EN);
1145
1146 free_irq(platform_get_irq(pdev, 0), sdd);
1147
1148 clk_disable(sdd->src_clk);
1149 clk_put(sdd->src_clk);
1150
1151 clk_disable(sdd->clk);
1152 clk_put(sdd->clk);
1153
1154 iounmap((void *) sdd->regs);
1155
1156 mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1157 if (mem_res != NULL)
1158 release_mem_region(mem_res->start, resource_size(mem_res));
1159
1160 platform_set_drvdata(pdev, NULL);
1161 spi_master_put(master);
1162
1163 return 0;
1164}
1165
1166#ifdef CONFIG_PM
1167static int s3c64xx_spi_suspend(struct device *dev)
1168{
1169 struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
1170 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1171
1172 spi_master_suspend(master);
1173
1174 /* Disable the clock */
1175 clk_disable(sdd->src_clk);
1176 clk_disable(sdd->clk);
1177
1178 sdd->cur_speed = 0; /* Output Clock is stopped */
1179
1180 return 0;
1181}
1182
1183static int s3c64xx_spi_resume(struct device *dev)
1184{
1185 struct platform_device *pdev = to_platform_device(dev);
1186 struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
1187 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1188 struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1189
1190 sci->cfg_gpio(pdev);
1191
1192 /* Enable the clock */
1193 clk_enable(sdd->src_clk);
1194 clk_enable(sdd->clk);
1195
1196 s3c64xx_spi_hwinit(sdd, pdev->id);
1197
1198 spi_master_resume(master);
1199
1200 return 0;
1201}
1202#endif /* CONFIG_PM */
1203
1204#ifdef CONFIG_PM_RUNTIME
1205static int s3c64xx_spi_runtime_suspend(struct device *dev)
1206{
1207 struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
1208 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1209
1210 clk_disable(sdd->clk);
1211 clk_disable(sdd->src_clk);
1212
1213 return 0;
1214}
1215
1216static int s3c64xx_spi_runtime_resume(struct device *dev)
1217{
1218 struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
1219 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1220
1221 clk_enable(sdd->src_clk);
1222 clk_enable(sdd->clk);
1223
1224 return 0;
1225}
1226#endif /* CONFIG_PM_RUNTIME */
1227
1228static const struct dev_pm_ops s3c64xx_spi_pm = {
1229 SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume)
1230 SET_RUNTIME_PM_OPS(s3c64xx_spi_runtime_suspend,
1231 s3c64xx_spi_runtime_resume, NULL)
1232};
1233
1234static struct platform_driver s3c64xx_spi_driver = {
1235 .driver = {
1236 .name = "s3c64xx-spi",
1237 .owner = THIS_MODULE,
1238 .pm = &s3c64xx_spi_pm,
1239 },
1240 .remove = s3c64xx_spi_remove,
1241};
1242MODULE_ALIAS("platform:s3c64xx-spi");
1243
1244static int __init s3c64xx_spi_init(void)
1245{
1246 return platform_driver_probe(&s3c64xx_spi_driver, s3c64xx_spi_probe);
1247}
1248subsys_initcall(s3c64xx_spi_init);
1249
1250static void __exit s3c64xx_spi_exit(void)
1251{
1252 platform_driver_unregister(&s3c64xx_spi_driver);
1253}
1254module_exit(s3c64xx_spi_exit);
1255
1256MODULE_AUTHOR("Jaswinder Singh <jassi.brar@samsung.com>");
1257MODULE_DESCRIPTION("S3C64XX SPI Controller Driver");
1258MODULE_LICENSE("GPL");