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/gpio.h>
17 #include <linux/of.h>
18 #include <linux/of_gpio.h>
19
20 #include <linux/platform_data/spi-s3c64xx.h>
21
22 #define MAX_SPI_PORTS 6
23 #define S3C64XX_SPI_QUIRK_POLL (1 << 0)
24 #define S3C64XX_SPI_QUIRK_CS_AUTO (1 << 1)
25 #define AUTOSUSPEND_TIMEOUT 2000
26
27 /* Registers and bit-fields */
28
29 #define S3C64XX_SPI_CH_CFG 0x00
30 #define S3C64XX_SPI_CLK_CFG 0x04
31 #define S3C64XX_SPI_MODE_CFG 0x08
32 #define S3C64XX_SPI_CS_REG 0x0C
33 #define S3C64XX_SPI_INT_EN 0x10
34 #define S3C64XX_SPI_STATUS 0x14
35 #define S3C64XX_SPI_TX_DATA 0x18
36 #define S3C64XX_SPI_RX_DATA 0x1C
37 #define S3C64XX_SPI_PACKET_CNT 0x20
38 #define S3C64XX_SPI_PENDING_CLR 0x24
39 #define S3C64XX_SPI_SWAP_CFG 0x28
40 #define S3C64XX_SPI_FB_CLK 0x2C
41
42 #define S3C64XX_SPI_CH_HS_EN (1<<6) /* High Speed Enable */
43 #define S3C64XX_SPI_CH_SW_RST (1<<5)
44 #define S3C64XX_SPI_CH_SLAVE (1<<4)
45 #define S3C64XX_SPI_CPOL_L (1<<3)
46 #define S3C64XX_SPI_CPHA_B (1<<2)
47 #define S3C64XX_SPI_CH_RXCH_ON (1<<1)
48 #define S3C64XX_SPI_CH_TXCH_ON (1<<0)
49
50 #define S3C64XX_SPI_CLKSEL_SRCMSK (3<<9)
51 #define S3C64XX_SPI_CLKSEL_SRCSHFT 9
52 #define S3C64XX_SPI_ENCLK_ENABLE (1<<8)
53 #define S3C64XX_SPI_PSR_MASK 0xff
54
55 #define S3C64XX_SPI_MODE_CH_TSZ_BYTE (0<<29)
56 #define S3C64XX_SPI_MODE_CH_TSZ_HALFWORD (1<<29)
57 #define S3C64XX_SPI_MODE_CH_TSZ_WORD (2<<29)
58 #define S3C64XX_SPI_MODE_CH_TSZ_MASK (3<<29)
59 #define S3C64XX_SPI_MODE_BUS_TSZ_BYTE (0<<17)
60 #define S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD (1<<17)
61 #define S3C64XX_SPI_MODE_BUS_TSZ_WORD (2<<17)
62 #define S3C64XX_SPI_MODE_BUS_TSZ_MASK (3<<17)
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 msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
119 #define is_polling(x) (x->port_conf->quirks & S3C64XX_SPI_QUIRK_POLL)
120
121 #define RXBUSY (1<<2)
122 #define TXBUSY (1<<3)
123
124 struct s3c64xx_spi_dma_data {
125 struct dma_chan *ch;
126 dma_cookie_t cookie;
127 enum dma_transfer_direction direction;
128 };
129
130 /**
131 * struct s3c64xx_spi_info - SPI Controller hardware info
132 * @fifo_lvl_mask: Bit-mask for {TX|RX}_FIFO_LVL bits in SPI_STATUS register.
133 * @rx_lvl_offset: Bit offset of RX_FIFO_LVL bits in SPI_STATUS regiter.
134 * @tx_st_done: Bit offset of TX_DONE bit in SPI_STATUS regiter.
135 * @quirks: Bitmask of known quirks
136 * @high_speed: True, if the controller supports HIGH_SPEED_EN bit.
137 * @clk_from_cmu: True, if the controller does not include a clock mux and
138 * prescaler unit.
139 * @clk_ioclk: True if clock is present on this device
140 *
141 * The Samsung s3c64xx SPI controller are used on various Samsung SoC's but
142 * differ in some aspects such as the size of the fifo and spi bus clock
143 * setup. Such differences are specified to the driver using this structure
144 * which is provided as driver data to the driver.
145 */
146 struct s3c64xx_spi_port_config {
147 int fifo_lvl_mask[MAX_SPI_PORTS];
148 int rx_lvl_offset;
149 int tx_st_done;
150 int quirks;
151 bool high_speed;
152 bool clk_from_cmu;
153 bool clk_ioclk;
154 };
155
156 /**
157 * struct s3c64xx_spi_driver_data - Runtime info holder for SPI driver.
158 * @clk: Pointer to the spi clock.
159 * @src_clk: Pointer to the clock used to generate SPI signals.
160 * @ioclk: Pointer to the i/o clock between master and slave
161 * @pdev: Pointer to device's platform device data
162 * @master: Pointer to the SPI Protocol master.
163 * @cntrlr_info: Platform specific data for the controller this driver manages.
164 * @lock: Controller specific lock.
165 * @state: Set of FLAGS to indicate status.
166 * @sfr_start: BUS address of SPI controller regs.
167 * @regs: Pointer to ioremap'ed controller registers.
168 * @xfer_completion: To indicate completion of xfer task.
169 * @cur_mode: Stores the active configuration of the controller.
170 * @cur_bpw: Stores the active bits per word settings.
171 * @cur_speed: Current clock speed
172 * @rx_dma: Local receive DMA data (e.g. chan and direction)
173 * @tx_dma: Local transmit DMA data (e.g. chan and direction)
174 * @port_conf: Local SPI port configuartion data
175 * @port_id: Port identification number
176 */
177 struct s3c64xx_spi_driver_data {
178 void __iomem *regs;
179 struct clk *clk;
180 struct clk *src_clk;
181 struct clk *ioclk;
182 struct platform_device *pdev;
183 struct spi_master *master;
184 struct s3c64xx_spi_info *cntrlr_info;
185 spinlock_t lock;
186 unsigned long sfr_start;
187 struct completion xfer_completion;
188 unsigned state;
189 unsigned cur_mode, cur_bpw;
190 unsigned cur_speed;
191 struct s3c64xx_spi_dma_data rx_dma;
192 struct s3c64xx_spi_dma_data tx_dma;
193 struct s3c64xx_spi_port_config *port_conf;
194 unsigned int port_id;
195 };
196
s3c64xx_flush_fifo(struct s3c64xx_spi_driver_data * sdd)197 static void s3c64xx_flush_fifo(struct s3c64xx_spi_driver_data *sdd)
198 {
199 void __iomem *regs = sdd->regs;
200 unsigned long loops;
201 u32 val;
202
203 writel(0, regs + S3C64XX_SPI_PACKET_CNT);
204
205 val = readl(regs + S3C64XX_SPI_CH_CFG);
206 val &= ~(S3C64XX_SPI_CH_RXCH_ON | S3C64XX_SPI_CH_TXCH_ON);
207 writel(val, regs + S3C64XX_SPI_CH_CFG);
208
209 val = readl(regs + S3C64XX_SPI_CH_CFG);
210 val |= S3C64XX_SPI_CH_SW_RST;
211 val &= ~S3C64XX_SPI_CH_HS_EN;
212 writel(val, regs + S3C64XX_SPI_CH_CFG);
213
214 /* Flush TxFIFO*/
215 loops = msecs_to_loops(1);
216 do {
217 val = readl(regs + S3C64XX_SPI_STATUS);
218 } while (TX_FIFO_LVL(val, sdd) && loops--);
219
220 if (loops == 0)
221 dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n");
222
223 /* Flush RxFIFO*/
224 loops = msecs_to_loops(1);
225 do {
226 val = readl(regs + S3C64XX_SPI_STATUS);
227 if (RX_FIFO_LVL(val, sdd))
228 readl(regs + S3C64XX_SPI_RX_DATA);
229 else
230 break;
231 } while (loops--);
232
233 if (loops == 0)
234 dev_warn(&sdd->pdev->dev, "Timed out flushing RX FIFO\n");
235
236 val = readl(regs + S3C64XX_SPI_CH_CFG);
237 val &= ~S3C64XX_SPI_CH_SW_RST;
238 writel(val, regs + S3C64XX_SPI_CH_CFG);
239
240 val = readl(regs + S3C64XX_SPI_MODE_CFG);
241 val &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
242 writel(val, regs + S3C64XX_SPI_MODE_CFG);
243 }
244
s3c64xx_spi_dmacb(void * data)245 static void s3c64xx_spi_dmacb(void *data)
246 {
247 struct s3c64xx_spi_driver_data *sdd;
248 struct s3c64xx_spi_dma_data *dma = data;
249 unsigned long flags;
250
251 if (dma->direction == DMA_DEV_TO_MEM)
252 sdd = container_of(data,
253 struct s3c64xx_spi_driver_data, rx_dma);
254 else
255 sdd = container_of(data,
256 struct s3c64xx_spi_driver_data, tx_dma);
257
258 spin_lock_irqsave(&sdd->lock, flags);
259
260 if (dma->direction == DMA_DEV_TO_MEM) {
261 sdd->state &= ~RXBUSY;
262 if (!(sdd->state & TXBUSY))
263 complete(&sdd->xfer_completion);
264 } else {
265 sdd->state &= ~TXBUSY;
266 if (!(sdd->state & RXBUSY))
267 complete(&sdd->xfer_completion);
268 }
269
270 spin_unlock_irqrestore(&sdd->lock, flags);
271 }
272
prepare_dma(struct s3c64xx_spi_dma_data * dma,struct sg_table * sgt)273 static int prepare_dma(struct s3c64xx_spi_dma_data *dma,
274 struct sg_table *sgt)
275 {
276 struct s3c64xx_spi_driver_data *sdd;
277 struct dma_slave_config config;
278 struct dma_async_tx_descriptor *desc;
279 int ret;
280
281 memset(&config, 0, sizeof(config));
282
283 if (dma->direction == DMA_DEV_TO_MEM) {
284 sdd = container_of((void *)dma,
285 struct s3c64xx_spi_driver_data, rx_dma);
286 config.direction = dma->direction;
287 config.src_addr = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
288 config.src_addr_width = sdd->cur_bpw / 8;
289 config.src_maxburst = 1;
290 dmaengine_slave_config(dma->ch, &config);
291 } else {
292 sdd = container_of((void *)dma,
293 struct s3c64xx_spi_driver_data, tx_dma);
294 config.direction = dma->direction;
295 config.dst_addr = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
296 config.dst_addr_width = sdd->cur_bpw / 8;
297 config.dst_maxburst = 1;
298 dmaengine_slave_config(dma->ch, &config);
299 }
300
301 desc = dmaengine_prep_slave_sg(dma->ch, sgt->sgl, sgt->nents,
302 dma->direction, DMA_PREP_INTERRUPT);
303 if (!desc) {
304 dev_err(&sdd->pdev->dev, "unable to prepare %s scatterlist",
305 dma->direction == DMA_DEV_TO_MEM ? "rx" : "tx");
306 return -ENOMEM;
307 }
308
309 desc->callback = s3c64xx_spi_dmacb;
310 desc->callback_param = dma;
311
312 dma->cookie = dmaengine_submit(desc);
313 ret = dma_submit_error(dma->cookie);
314 if (ret) {
315 dev_err(&sdd->pdev->dev, "DMA submission failed");
316 return -EIO;
317 }
318
319 dma_async_issue_pending(dma->ch);
320 return 0;
321 }
322
s3c64xx_spi_set_cs(struct spi_device * spi,bool enable)323 static void s3c64xx_spi_set_cs(struct spi_device *spi, bool enable)
324 {
325 struct s3c64xx_spi_driver_data *sdd =
326 spi_master_get_devdata(spi->master);
327
328 if (sdd->cntrlr_info->no_cs)
329 return;
330
331 if (enable) {
332 if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO)) {
333 writel(0, sdd->regs + S3C64XX_SPI_CS_REG);
334 } else {
335 u32 ssel = readl(sdd->regs + S3C64XX_SPI_CS_REG);
336
337 ssel |= (S3C64XX_SPI_CS_AUTO |
338 S3C64XX_SPI_CS_NSC_CNT_2);
339 writel(ssel, sdd->regs + S3C64XX_SPI_CS_REG);
340 }
341 } else {
342 if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
343 writel(S3C64XX_SPI_CS_SIG_INACT,
344 sdd->regs + S3C64XX_SPI_CS_REG);
345 }
346 }
347
s3c64xx_spi_prepare_transfer(struct spi_master * spi)348 static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
349 {
350 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
351
352 if (is_polling(sdd))
353 return 0;
354
355 spi->dma_rx = sdd->rx_dma.ch;
356 spi->dma_tx = sdd->tx_dma.ch;
357
358 return 0;
359 }
360
s3c64xx_spi_can_dma(struct spi_master * master,struct spi_device * spi,struct spi_transfer * xfer)361 static bool s3c64xx_spi_can_dma(struct spi_master *master,
362 struct spi_device *spi,
363 struct spi_transfer *xfer)
364 {
365 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
366
367 return xfer->len > (FIFO_LVL_MASK(sdd) >> 1) + 1;
368 }
369
s3c64xx_enable_datapath(struct s3c64xx_spi_driver_data * sdd,struct spi_transfer * xfer,int dma_mode)370 static int s3c64xx_enable_datapath(struct s3c64xx_spi_driver_data *sdd,
371 struct spi_transfer *xfer, int dma_mode)
372 {
373 void __iomem *regs = sdd->regs;
374 u32 modecfg, chcfg;
375 int ret = 0;
376
377 modecfg = readl(regs + S3C64XX_SPI_MODE_CFG);
378 modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
379
380 chcfg = readl(regs + S3C64XX_SPI_CH_CFG);
381 chcfg &= ~S3C64XX_SPI_CH_TXCH_ON;
382
383 if (dma_mode) {
384 chcfg &= ~S3C64XX_SPI_CH_RXCH_ON;
385 } else {
386 /* Always shift in data in FIFO, even if xfer is Tx only,
387 * this helps setting PCKT_CNT value for generating clocks
388 * as exactly needed.
389 */
390 chcfg |= S3C64XX_SPI_CH_RXCH_ON;
391 writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
392 | S3C64XX_SPI_PACKET_CNT_EN,
393 regs + S3C64XX_SPI_PACKET_CNT);
394 }
395
396 if (xfer->tx_buf != NULL) {
397 sdd->state |= TXBUSY;
398 chcfg |= S3C64XX_SPI_CH_TXCH_ON;
399 if (dma_mode) {
400 modecfg |= S3C64XX_SPI_MODE_TXDMA_ON;
401 ret = prepare_dma(&sdd->tx_dma, &xfer->tx_sg);
402 } else {
403 switch (sdd->cur_bpw) {
404 case 32:
405 iowrite32_rep(regs + S3C64XX_SPI_TX_DATA,
406 xfer->tx_buf, xfer->len / 4);
407 break;
408 case 16:
409 iowrite16_rep(regs + S3C64XX_SPI_TX_DATA,
410 xfer->tx_buf, xfer->len / 2);
411 break;
412 default:
413 iowrite8_rep(regs + S3C64XX_SPI_TX_DATA,
414 xfer->tx_buf, xfer->len);
415 break;
416 }
417 }
418 }
419
420 if (xfer->rx_buf != NULL) {
421 sdd->state |= RXBUSY;
422
423 if (sdd->port_conf->high_speed && sdd->cur_speed >= 30000000UL
424 && !(sdd->cur_mode & SPI_CPHA))
425 chcfg |= S3C64XX_SPI_CH_HS_EN;
426
427 if (dma_mode) {
428 modecfg |= S3C64XX_SPI_MODE_RXDMA_ON;
429 chcfg |= S3C64XX_SPI_CH_RXCH_ON;
430 writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
431 | S3C64XX_SPI_PACKET_CNT_EN,
432 regs + S3C64XX_SPI_PACKET_CNT);
433 ret = prepare_dma(&sdd->rx_dma, &xfer->rx_sg);
434 }
435 }
436
437 if (ret)
438 return ret;
439
440 writel(modecfg, regs + S3C64XX_SPI_MODE_CFG);
441 writel(chcfg, regs + S3C64XX_SPI_CH_CFG);
442
443 return 0;
444 }
445
s3c64xx_spi_wait_for_timeout(struct s3c64xx_spi_driver_data * sdd,int timeout_ms)446 static u32 s3c64xx_spi_wait_for_timeout(struct s3c64xx_spi_driver_data *sdd,
447 int timeout_ms)
448 {
449 void __iomem *regs = sdd->regs;
450 unsigned long val = 1;
451 u32 status;
452
453 /* max fifo depth available */
454 u32 max_fifo = (FIFO_LVL_MASK(sdd) >> 1) + 1;
455
456 if (timeout_ms)
457 val = msecs_to_loops(timeout_ms);
458
459 do {
460 status = readl(regs + S3C64XX_SPI_STATUS);
461 } while (RX_FIFO_LVL(status, sdd) < max_fifo && --val);
462
463 /* return the actual received data length */
464 return RX_FIFO_LVL(status, sdd);
465 }
466
s3c64xx_wait_for_dma(struct s3c64xx_spi_driver_data * sdd,struct spi_transfer * xfer)467 static int s3c64xx_wait_for_dma(struct s3c64xx_spi_driver_data *sdd,
468 struct spi_transfer *xfer)
469 {
470 void __iomem *regs = sdd->regs;
471 unsigned long val;
472 u32 status;
473 int ms;
474
475 /* millisecs to xfer 'len' bytes @ 'cur_speed' */
476 ms = xfer->len * 8 * 1000 / sdd->cur_speed;
477 ms += 30; /* some tolerance */
478 ms = max(ms, 100); /* minimum timeout */
479
480 val = msecs_to_jiffies(ms) + 10;
481 val = wait_for_completion_timeout(&sdd->xfer_completion, val);
482
483 /*
484 * If the previous xfer was completed within timeout, then
485 * proceed further else return -EIO.
486 * DmaTx returns after simply writing data in the FIFO,
487 * w/o waiting for real transmission on the bus to finish.
488 * DmaRx returns only after Dma read data from FIFO which
489 * needs bus transmission to finish, so we don't worry if
490 * Xfer involved Rx(with or without Tx).
491 */
492 if (val && !xfer->rx_buf) {
493 val = msecs_to_loops(10);
494 status = readl(regs + S3C64XX_SPI_STATUS);
495 while ((TX_FIFO_LVL(status, sdd)
496 || !S3C64XX_SPI_ST_TX_DONE(status, sdd))
497 && --val) {
498 cpu_relax();
499 status = readl(regs + S3C64XX_SPI_STATUS);
500 }
501
502 }
503
504 /* If timed out while checking rx/tx status return error */
505 if (!val)
506 return -EIO;
507
508 return 0;
509 }
510
s3c64xx_wait_for_pio(struct s3c64xx_spi_driver_data * sdd,struct spi_transfer * xfer)511 static int s3c64xx_wait_for_pio(struct s3c64xx_spi_driver_data *sdd,
512 struct spi_transfer *xfer)
513 {
514 void __iomem *regs = sdd->regs;
515 unsigned long val;
516 u32 status;
517 int loops;
518 u32 cpy_len;
519 u8 *buf;
520 int ms;
521
522 /* millisecs to xfer 'len' bytes @ 'cur_speed' */
523 ms = xfer->len * 8 * 1000 / sdd->cur_speed;
524 ms += 10; /* some tolerance */
525
526 val = msecs_to_loops(ms);
527 do {
528 status = readl(regs + S3C64XX_SPI_STATUS);
529 } while (RX_FIFO_LVL(status, sdd) < xfer->len && --val);
530
531 if (!val)
532 return -EIO;
533
534 /* If it was only Tx */
535 if (!xfer->rx_buf) {
536 sdd->state &= ~TXBUSY;
537 return 0;
538 }
539
540 /*
541 * If the receive length is bigger than the controller fifo
542 * size, calculate the loops and read the fifo as many times.
543 * loops = length / max fifo size (calculated by using the
544 * fifo mask).
545 * For any size less than the fifo size the below code is
546 * executed atleast once.
547 */
548 loops = xfer->len / ((FIFO_LVL_MASK(sdd) >> 1) + 1);
549 buf = xfer->rx_buf;
550 do {
551 /* wait for data to be received in the fifo */
552 cpy_len = s3c64xx_spi_wait_for_timeout(sdd,
553 (loops ? ms : 0));
554
555 switch (sdd->cur_bpw) {
556 case 32:
557 ioread32_rep(regs + S3C64XX_SPI_RX_DATA,
558 buf, cpy_len / 4);
559 break;
560 case 16:
561 ioread16_rep(regs + S3C64XX_SPI_RX_DATA,
562 buf, cpy_len / 2);
563 break;
564 default:
565 ioread8_rep(regs + S3C64XX_SPI_RX_DATA,
566 buf, cpy_len);
567 break;
568 }
569
570 buf = buf + cpy_len;
571 } while (loops--);
572 sdd->state &= ~RXBUSY;
573
574 return 0;
575 }
576
s3c64xx_spi_config(struct s3c64xx_spi_driver_data * sdd)577 static int s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
578 {
579 void __iomem *regs = sdd->regs;
580 int ret;
581 u32 val;
582
583 /* Disable Clock */
584 if (!sdd->port_conf->clk_from_cmu) {
585 val = readl(regs + S3C64XX_SPI_CLK_CFG);
586 val &= ~S3C64XX_SPI_ENCLK_ENABLE;
587 writel(val, regs + S3C64XX_SPI_CLK_CFG);
588 }
589
590 /* Set Polarity and Phase */
591 val = readl(regs + S3C64XX_SPI_CH_CFG);
592 val &= ~(S3C64XX_SPI_CH_SLAVE |
593 S3C64XX_SPI_CPOL_L |
594 S3C64XX_SPI_CPHA_B);
595
596 if (sdd->cur_mode & SPI_CPOL)
597 val |= S3C64XX_SPI_CPOL_L;
598
599 if (sdd->cur_mode & SPI_CPHA)
600 val |= S3C64XX_SPI_CPHA_B;
601
602 writel(val, regs + S3C64XX_SPI_CH_CFG);
603
604 /* Set Channel & DMA Mode */
605 val = readl(regs + S3C64XX_SPI_MODE_CFG);
606 val &= ~(S3C64XX_SPI_MODE_BUS_TSZ_MASK
607 | S3C64XX_SPI_MODE_CH_TSZ_MASK);
608
609 switch (sdd->cur_bpw) {
610 case 32:
611 val |= S3C64XX_SPI_MODE_BUS_TSZ_WORD;
612 val |= S3C64XX_SPI_MODE_CH_TSZ_WORD;
613 break;
614 case 16:
615 val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD;
616 val |= S3C64XX_SPI_MODE_CH_TSZ_HALFWORD;
617 break;
618 default:
619 val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE;
620 val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE;
621 break;
622 }
623
624 writel(val, regs + S3C64XX_SPI_MODE_CFG);
625
626 if (sdd->port_conf->clk_from_cmu) {
627 /* The src_clk clock is divided internally by 2 */
628 ret = clk_set_rate(sdd->src_clk, sdd->cur_speed * 2);
629 if (ret)
630 return ret;
631 sdd->cur_speed = clk_get_rate(sdd->src_clk) / 2;
632 } else {
633 /* Configure Clock */
634 val = readl(regs + S3C64XX_SPI_CLK_CFG);
635 val &= ~S3C64XX_SPI_PSR_MASK;
636 val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / 2 - 1)
637 & S3C64XX_SPI_PSR_MASK);
638 writel(val, regs + S3C64XX_SPI_CLK_CFG);
639
640 /* Enable Clock */
641 val = readl(regs + S3C64XX_SPI_CLK_CFG);
642 val |= S3C64XX_SPI_ENCLK_ENABLE;
643 writel(val, regs + S3C64XX_SPI_CLK_CFG);
644 }
645
646 return 0;
647 }
648
649 #define XFER_DMAADDR_INVALID DMA_BIT_MASK(32)
650
s3c64xx_spi_prepare_message(struct spi_master * master,struct spi_message * msg)651 static int s3c64xx_spi_prepare_message(struct spi_master *master,
652 struct spi_message *msg)
653 {
654 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
655 struct spi_device *spi = msg->spi;
656 struct s3c64xx_spi_csinfo *cs = spi->controller_data;
657
658 /* Configure feedback delay */
659 writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK);
660
661 return 0;
662 }
663
s3c64xx_spi_max_transfer_size(struct spi_device * spi)664 static size_t s3c64xx_spi_max_transfer_size(struct spi_device *spi)
665 {
666 struct spi_controller *ctlr = spi->controller;
667
668 return ctlr->can_dma ? S3C64XX_SPI_PACKET_CNT_MASK : SIZE_MAX;
669 }
670
s3c64xx_spi_transfer_one(struct spi_master * master,struct spi_device * spi,struct spi_transfer * xfer)671 static int s3c64xx_spi_transfer_one(struct spi_master *master,
672 struct spi_device *spi,
673 struct spi_transfer *xfer)
674 {
675 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
676 const unsigned int fifo_len = (FIFO_LVL_MASK(sdd) >> 1) + 1;
677 const void *tx_buf = NULL;
678 void *rx_buf = NULL;
679 int target_len = 0, origin_len = 0;
680 int use_dma = 0;
681 int status;
682 u32 speed;
683 u8 bpw;
684 unsigned long flags;
685
686 reinit_completion(&sdd->xfer_completion);
687
688 /* Only BPW and Speed may change across transfers */
689 bpw = xfer->bits_per_word;
690 speed = xfer->speed_hz;
691
692 if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) {
693 sdd->cur_bpw = bpw;
694 sdd->cur_speed = speed;
695 sdd->cur_mode = spi->mode;
696 status = s3c64xx_spi_config(sdd);
697 if (status)
698 return status;
699 }
700
701 if (!is_polling(sdd) && (xfer->len > fifo_len) &&
702 sdd->rx_dma.ch && sdd->tx_dma.ch) {
703 use_dma = 1;
704
705 } else if (is_polling(sdd) && xfer->len > fifo_len) {
706 tx_buf = xfer->tx_buf;
707 rx_buf = xfer->rx_buf;
708 origin_len = xfer->len;
709
710 target_len = xfer->len;
711 if (xfer->len > fifo_len)
712 xfer->len = fifo_len;
713 }
714
715 do {
716 spin_lock_irqsave(&sdd->lock, flags);
717
718 /* Pending only which is to be done */
719 sdd->state &= ~RXBUSY;
720 sdd->state &= ~TXBUSY;
721
722 /* Start the signals */
723 s3c64xx_spi_set_cs(spi, true);
724
725 status = s3c64xx_enable_datapath(sdd, xfer, use_dma);
726
727 spin_unlock_irqrestore(&sdd->lock, flags);
728
729 if (status) {
730 dev_err(&spi->dev, "failed to enable data path for transfer: %d\n", status);
731 break;
732 }
733
734 if (use_dma)
735 status = s3c64xx_wait_for_dma(sdd, xfer);
736 else
737 status = s3c64xx_wait_for_pio(sdd, xfer);
738
739 if (status) {
740 dev_err(&spi->dev,
741 "I/O Error: rx-%d tx-%d rx-%c tx-%c len-%d dma-%d res-(%d)\n",
742 xfer->rx_buf ? 1 : 0, xfer->tx_buf ? 1 : 0,
743 (sdd->state & RXBUSY) ? 'f' : 'p',
744 (sdd->state & TXBUSY) ? 'f' : 'p',
745 xfer->len, use_dma ? 1 : 0, status);
746
747 if (use_dma) {
748 struct dma_tx_state s;
749
750 if (xfer->tx_buf && (sdd->state & TXBUSY)) {
751 dmaengine_pause(sdd->tx_dma.ch);
752 dmaengine_tx_status(sdd->tx_dma.ch, sdd->tx_dma.cookie, &s);
753 dmaengine_terminate_all(sdd->tx_dma.ch);
754 dev_err(&spi->dev, "TX residue: %d\n", s.residue);
755
756 }
757 if (xfer->rx_buf && (sdd->state & RXBUSY)) {
758 dmaengine_pause(sdd->rx_dma.ch);
759 dmaengine_tx_status(sdd->rx_dma.ch, sdd->rx_dma.cookie, &s);
760 dmaengine_terminate_all(sdd->rx_dma.ch);
761 dev_err(&spi->dev, "RX residue: %d\n", s.residue);
762 }
763 }
764 } else {
765 s3c64xx_flush_fifo(sdd);
766 }
767 if (target_len > 0) {
768 target_len -= xfer->len;
769
770 if (xfer->tx_buf)
771 xfer->tx_buf += xfer->len;
772
773 if (xfer->rx_buf)
774 xfer->rx_buf += xfer->len;
775
776 if (target_len > fifo_len)
777 xfer->len = fifo_len;
778 else
779 xfer->len = target_len;
780 }
781 } while (target_len > 0);
782
783 if (origin_len) {
784 /* Restore original xfer buffers and length */
785 xfer->tx_buf = tx_buf;
786 xfer->rx_buf = rx_buf;
787 xfer->len = origin_len;
788 }
789
790 return status;
791 }
792
s3c64xx_get_slave_ctrldata(struct spi_device * spi)793 static struct s3c64xx_spi_csinfo *s3c64xx_get_slave_ctrldata(
794 struct spi_device *spi)
795 {
796 struct s3c64xx_spi_csinfo *cs;
797 struct device_node *slave_np, *data_np = NULL;
798 u32 fb_delay = 0;
799
800 slave_np = spi->dev.of_node;
801 if (!slave_np) {
802 dev_err(&spi->dev, "device node not found\n");
803 return ERR_PTR(-EINVAL);
804 }
805
806 data_np = of_get_child_by_name(slave_np, "controller-data");
807 if (!data_np) {
808 dev_err(&spi->dev, "child node 'controller-data' not found\n");
809 return ERR_PTR(-EINVAL);
810 }
811
812 cs = kzalloc(sizeof(*cs), GFP_KERNEL);
813 if (!cs) {
814 of_node_put(data_np);
815 return ERR_PTR(-ENOMEM);
816 }
817
818 of_property_read_u32(data_np, "samsung,spi-feedback-delay", &fb_delay);
819 cs->fb_delay = fb_delay;
820 of_node_put(data_np);
821 return cs;
822 }
823
824 /*
825 * Here we only check the validity of requested configuration
826 * and save the configuration in a local data-structure.
827 * The controller is actually configured only just before we
828 * get a message to transfer.
829 */
s3c64xx_spi_setup(struct spi_device * spi)830 static int s3c64xx_spi_setup(struct spi_device *spi)
831 {
832 struct s3c64xx_spi_csinfo *cs = spi->controller_data;
833 struct s3c64xx_spi_driver_data *sdd;
834 int err;
835
836 sdd = spi_master_get_devdata(spi->master);
837 if (spi->dev.of_node) {
838 cs = s3c64xx_get_slave_ctrldata(spi);
839 spi->controller_data = cs;
840 } else if (cs) {
841 /* On non-DT platforms the SPI core will set spi->cs_gpio
842 * to -ENOENT. The GPIO pin used to drive the chip select
843 * is defined by using platform data so spi->cs_gpio value
844 * has to be override to have the proper GPIO pin number.
845 */
846 spi->cs_gpio = cs->line;
847 }
848
849 if (IS_ERR_OR_NULL(cs)) {
850 dev_err(&spi->dev, "No CS for SPI(%d)\n", spi->chip_select);
851 return -ENODEV;
852 }
853
854 if (!spi_get_ctldata(spi)) {
855 if (gpio_is_valid(spi->cs_gpio)) {
856 err = gpio_request_one(spi->cs_gpio, GPIOF_OUT_INIT_HIGH,
857 dev_name(&spi->dev));
858 if (err) {
859 dev_err(&spi->dev,
860 "Failed to get /CS gpio [%d]: %d\n",
861 spi->cs_gpio, err);
862 goto err_gpio_req;
863 }
864 }
865
866 spi_set_ctldata(spi, cs);
867 }
868
869 pm_runtime_get_sync(&sdd->pdev->dev);
870
871 /* Check if we can provide the requested rate */
872 if (!sdd->port_conf->clk_from_cmu) {
873 u32 psr, speed;
874
875 /* Max possible */
876 speed = clk_get_rate(sdd->src_clk) / 2 / (0 + 1);
877
878 if (spi->max_speed_hz > speed)
879 spi->max_speed_hz = speed;
880
881 psr = clk_get_rate(sdd->src_clk) / 2 / spi->max_speed_hz - 1;
882 psr &= S3C64XX_SPI_PSR_MASK;
883 if (psr == S3C64XX_SPI_PSR_MASK)
884 psr--;
885
886 speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
887 if (spi->max_speed_hz < speed) {
888 if (psr+1 < S3C64XX_SPI_PSR_MASK) {
889 psr++;
890 } else {
891 err = -EINVAL;
892 goto setup_exit;
893 }
894 }
895
896 speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
897 if (spi->max_speed_hz >= speed) {
898 spi->max_speed_hz = speed;
899 } else {
900 dev_err(&spi->dev, "Can't set %dHz transfer speed\n",
901 spi->max_speed_hz);
902 err = -EINVAL;
903 goto setup_exit;
904 }
905 }
906
907 pm_runtime_mark_last_busy(&sdd->pdev->dev);
908 pm_runtime_put_autosuspend(&sdd->pdev->dev);
909 s3c64xx_spi_set_cs(spi, false);
910
911 return 0;
912
913 setup_exit:
914 pm_runtime_mark_last_busy(&sdd->pdev->dev);
915 pm_runtime_put_autosuspend(&sdd->pdev->dev);
916 /* setup() returns with device de-selected */
917 s3c64xx_spi_set_cs(spi, false);
918
919 if (gpio_is_valid(spi->cs_gpio))
920 gpio_free(spi->cs_gpio);
921 spi_set_ctldata(spi, NULL);
922
923 err_gpio_req:
924 if (spi->dev.of_node)
925 kfree(cs);
926
927 return err;
928 }
929
s3c64xx_spi_cleanup(struct spi_device * spi)930 static void s3c64xx_spi_cleanup(struct spi_device *spi)
931 {
932 struct s3c64xx_spi_csinfo *cs = spi_get_ctldata(spi);
933
934 if (gpio_is_valid(spi->cs_gpio)) {
935 gpio_free(spi->cs_gpio);
936 if (spi->dev.of_node)
937 kfree(cs);
938 else {
939 /* On non-DT platforms, the SPI core sets
940 * spi->cs_gpio to -ENOENT and .setup()
941 * overrides it with the GPIO pin value
942 * passed using platform data.
943 */
944 spi->cs_gpio = -ENOENT;
945 }
946 }
947
948 spi_set_ctldata(spi, NULL);
949 }
950
s3c64xx_spi_irq(int irq,void * data)951 static irqreturn_t s3c64xx_spi_irq(int irq, void *data)
952 {
953 struct s3c64xx_spi_driver_data *sdd = data;
954 struct spi_master *spi = sdd->master;
955 unsigned int val, clr = 0;
956
957 val = readl(sdd->regs + S3C64XX_SPI_STATUS);
958
959 if (val & S3C64XX_SPI_ST_RX_OVERRUN_ERR) {
960 clr = S3C64XX_SPI_PND_RX_OVERRUN_CLR;
961 dev_err(&spi->dev, "RX overrun\n");
962 }
963 if (val & S3C64XX_SPI_ST_RX_UNDERRUN_ERR) {
964 clr |= S3C64XX_SPI_PND_RX_UNDERRUN_CLR;
965 dev_err(&spi->dev, "RX underrun\n");
966 }
967 if (val & S3C64XX_SPI_ST_TX_OVERRUN_ERR) {
968 clr |= S3C64XX_SPI_PND_TX_OVERRUN_CLR;
969 dev_err(&spi->dev, "TX overrun\n");
970 }
971 if (val & S3C64XX_SPI_ST_TX_UNDERRUN_ERR) {
972 clr |= S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
973 dev_err(&spi->dev, "TX underrun\n");
974 }
975
976 /* Clear the pending irq by setting and then clearing it */
977 writel(clr, sdd->regs + S3C64XX_SPI_PENDING_CLR);
978 writel(0, sdd->regs + S3C64XX_SPI_PENDING_CLR);
979
980 return IRQ_HANDLED;
981 }
982
s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data * sdd)983 static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd)
984 {
985 struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
986 void __iomem *regs = sdd->regs;
987 unsigned int val;
988
989 sdd->cur_speed = 0;
990
991 if (sci->no_cs)
992 writel(0, sdd->regs + S3C64XX_SPI_CS_REG);
993 else if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
994 writel(S3C64XX_SPI_CS_SIG_INACT, sdd->regs + S3C64XX_SPI_CS_REG);
995
996 /* Disable Interrupts - we use Polling if not DMA mode */
997 writel(0, regs + S3C64XX_SPI_INT_EN);
998
999 if (!sdd->port_conf->clk_from_cmu)
1000 writel(sci->src_clk_nr << S3C64XX_SPI_CLKSEL_SRCSHFT,
1001 regs + S3C64XX_SPI_CLK_CFG);
1002 writel(0, regs + S3C64XX_SPI_MODE_CFG);
1003 writel(0, regs + S3C64XX_SPI_PACKET_CNT);
1004
1005 /* Clear any irq pending bits, should set and clear the bits */
1006 val = S3C64XX_SPI_PND_RX_OVERRUN_CLR |
1007 S3C64XX_SPI_PND_RX_UNDERRUN_CLR |
1008 S3C64XX_SPI_PND_TX_OVERRUN_CLR |
1009 S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
1010 writel(val, regs + S3C64XX_SPI_PENDING_CLR);
1011 writel(0, regs + S3C64XX_SPI_PENDING_CLR);
1012
1013 writel(0, regs + S3C64XX_SPI_SWAP_CFG);
1014
1015 val = readl(regs + S3C64XX_SPI_MODE_CFG);
1016 val &= ~S3C64XX_SPI_MODE_4BURST;
1017 val &= ~(S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
1018 val |= (S3C64XX_SPI_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
1019 writel(val, regs + S3C64XX_SPI_MODE_CFG);
1020
1021 s3c64xx_flush_fifo(sdd);
1022 }
1023
1024 #ifdef CONFIG_OF
s3c64xx_spi_parse_dt(struct device * dev)1025 static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
1026 {
1027 struct s3c64xx_spi_info *sci;
1028 u32 temp;
1029
1030 sci = devm_kzalloc(dev, sizeof(*sci), GFP_KERNEL);
1031 if (!sci)
1032 return ERR_PTR(-ENOMEM);
1033
1034 if (of_property_read_u32(dev->of_node, "samsung,spi-src-clk", &temp)) {
1035 dev_warn(dev, "spi bus clock parent not specified, using clock at index 0 as parent\n");
1036 sci->src_clk_nr = 0;
1037 } else {
1038 sci->src_clk_nr = temp;
1039 }
1040
1041 if (of_property_read_u32(dev->of_node, "num-cs", &temp)) {
1042 dev_warn(dev, "number of chip select lines not specified, assuming 1 chip select line\n");
1043 sci->num_cs = 1;
1044 } else {
1045 sci->num_cs = temp;
1046 }
1047
1048 sci->no_cs = of_property_read_bool(dev->of_node, "no-cs-readback");
1049
1050 return sci;
1051 }
1052 #else
s3c64xx_spi_parse_dt(struct device * dev)1053 static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
1054 {
1055 return dev_get_platdata(dev);
1056 }
1057 #endif
1058
1059 static const struct of_device_id s3c64xx_spi_dt_match[];
1060
s3c64xx_spi_get_port_config(struct platform_device * pdev)1061 static inline struct s3c64xx_spi_port_config *s3c64xx_spi_get_port_config(
1062 struct platform_device *pdev)
1063 {
1064 #ifdef CONFIG_OF
1065 if (pdev->dev.of_node) {
1066 const struct of_device_id *match;
1067 match = of_match_node(s3c64xx_spi_dt_match, pdev->dev.of_node);
1068 return (struct s3c64xx_spi_port_config *)match->data;
1069 }
1070 #endif
1071 return (struct s3c64xx_spi_port_config *)
1072 platform_get_device_id(pdev)->driver_data;
1073 }
1074
s3c64xx_spi_probe(struct platform_device * pdev)1075 static int s3c64xx_spi_probe(struct platform_device *pdev)
1076 {
1077 struct resource *mem_res;
1078 struct s3c64xx_spi_driver_data *sdd;
1079 struct s3c64xx_spi_info *sci = dev_get_platdata(&pdev->dev);
1080 struct spi_master *master;
1081 int ret, irq;
1082 char clk_name[16];
1083
1084 if (!sci && pdev->dev.of_node) {
1085 sci = s3c64xx_spi_parse_dt(&pdev->dev);
1086 if (IS_ERR(sci))
1087 return PTR_ERR(sci);
1088 }
1089
1090 if (!sci) {
1091 dev_err(&pdev->dev, "platform_data missing!\n");
1092 return -ENODEV;
1093 }
1094
1095 mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1096 if (mem_res == NULL) {
1097 dev_err(&pdev->dev, "Unable to get SPI MEM resource\n");
1098 return -ENXIO;
1099 }
1100
1101 irq = platform_get_irq(pdev, 0);
1102 if (irq < 0) {
1103 dev_warn(&pdev->dev, "Failed to get IRQ: %d\n", irq);
1104 return irq;
1105 }
1106
1107 master = spi_alloc_master(&pdev->dev,
1108 sizeof(struct s3c64xx_spi_driver_data));
1109 if (master == NULL) {
1110 dev_err(&pdev->dev, "Unable to allocate SPI Master\n");
1111 return -ENOMEM;
1112 }
1113
1114 platform_set_drvdata(pdev, master);
1115
1116 sdd = spi_master_get_devdata(master);
1117 sdd->port_conf = s3c64xx_spi_get_port_config(pdev);
1118 sdd->master = master;
1119 sdd->cntrlr_info = sci;
1120 sdd->pdev = pdev;
1121 sdd->sfr_start = mem_res->start;
1122 if (pdev->dev.of_node) {
1123 ret = of_alias_get_id(pdev->dev.of_node, "spi");
1124 if (ret < 0) {
1125 dev_err(&pdev->dev, "failed to get alias id, errno %d\n",
1126 ret);
1127 goto err_deref_master;
1128 }
1129 sdd->port_id = ret;
1130 } else {
1131 sdd->port_id = pdev->id;
1132 }
1133
1134 sdd->cur_bpw = 8;
1135
1136 sdd->tx_dma.direction = DMA_MEM_TO_DEV;
1137 sdd->rx_dma.direction = DMA_DEV_TO_MEM;
1138
1139 master->dev.of_node = pdev->dev.of_node;
1140 master->bus_num = sdd->port_id;
1141 master->setup = s3c64xx_spi_setup;
1142 master->cleanup = s3c64xx_spi_cleanup;
1143 master->prepare_transfer_hardware = s3c64xx_spi_prepare_transfer;
1144 master->prepare_message = s3c64xx_spi_prepare_message;
1145 master->transfer_one = s3c64xx_spi_transfer_one;
1146 master->max_transfer_size = s3c64xx_spi_max_transfer_size;
1147 master->num_chipselect = sci->num_cs;
1148 master->dma_alignment = 8;
1149 master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) |
1150 SPI_BPW_MASK(8);
1151 /* the spi->mode bits understood by this driver: */
1152 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1153 master->auto_runtime_pm = true;
1154 if (!is_polling(sdd))
1155 master->can_dma = s3c64xx_spi_can_dma;
1156
1157 sdd->regs = devm_ioremap_resource(&pdev->dev, mem_res);
1158 if (IS_ERR(sdd->regs)) {
1159 ret = PTR_ERR(sdd->regs);
1160 goto err_deref_master;
1161 }
1162
1163 if (sci->cfg_gpio && sci->cfg_gpio()) {
1164 dev_err(&pdev->dev, "Unable to config gpio\n");
1165 ret = -EBUSY;
1166 goto err_deref_master;
1167 }
1168
1169 /* Setup clocks */
1170 sdd->clk = devm_clk_get(&pdev->dev, "spi");
1171 if (IS_ERR(sdd->clk)) {
1172 dev_err(&pdev->dev, "Unable to acquire clock 'spi'\n");
1173 ret = PTR_ERR(sdd->clk);
1174 goto err_deref_master;
1175 }
1176
1177 ret = clk_prepare_enable(sdd->clk);
1178 if (ret) {
1179 dev_err(&pdev->dev, "Couldn't enable clock 'spi'\n");
1180 goto err_deref_master;
1181 }
1182
1183 sprintf(clk_name, "spi_busclk%d", sci->src_clk_nr);
1184 sdd->src_clk = devm_clk_get(&pdev->dev, clk_name);
1185 if (IS_ERR(sdd->src_clk)) {
1186 dev_err(&pdev->dev,
1187 "Unable to acquire clock '%s'\n", clk_name);
1188 ret = PTR_ERR(sdd->src_clk);
1189 goto err_disable_clk;
1190 }
1191
1192 ret = clk_prepare_enable(sdd->src_clk);
1193 if (ret) {
1194 dev_err(&pdev->dev, "Couldn't enable clock '%s'\n", clk_name);
1195 goto err_disable_clk;
1196 }
1197
1198 if (sdd->port_conf->clk_ioclk) {
1199 sdd->ioclk = devm_clk_get(&pdev->dev, "spi_ioclk");
1200 if (IS_ERR(sdd->ioclk)) {
1201 dev_err(&pdev->dev, "Unable to acquire 'ioclk'\n");
1202 ret = PTR_ERR(sdd->ioclk);
1203 goto err_disable_src_clk;
1204 }
1205
1206 ret = clk_prepare_enable(sdd->ioclk);
1207 if (ret) {
1208 dev_err(&pdev->dev, "Couldn't enable clock 'ioclk'\n");
1209 goto err_disable_src_clk;
1210 }
1211 }
1212
1213 if (!is_polling(sdd)) {
1214 /* Acquire DMA channels */
1215 sdd->rx_dma.ch = dma_request_chan(&pdev->dev, "rx");
1216 if (IS_ERR(sdd->rx_dma.ch)) {
1217 dev_err(&pdev->dev, "Failed to get RX DMA channel\n");
1218 ret = PTR_ERR(sdd->rx_dma.ch);
1219 goto err_disable_io_clk;
1220 }
1221 sdd->tx_dma.ch = dma_request_chan(&pdev->dev, "tx");
1222 if (IS_ERR(sdd->tx_dma.ch)) {
1223 dev_err(&pdev->dev, "Failed to get TX DMA channel\n");
1224 ret = PTR_ERR(sdd->tx_dma.ch);
1225 goto err_release_rx_dma;
1226 }
1227 }
1228
1229 pm_runtime_set_autosuspend_delay(&pdev->dev, AUTOSUSPEND_TIMEOUT);
1230 pm_runtime_use_autosuspend(&pdev->dev);
1231 pm_runtime_set_active(&pdev->dev);
1232 pm_runtime_enable(&pdev->dev);
1233 pm_runtime_get_sync(&pdev->dev);
1234
1235 /* Setup Deufult Mode */
1236 s3c64xx_spi_hwinit(sdd);
1237
1238 spin_lock_init(&sdd->lock);
1239 init_completion(&sdd->xfer_completion);
1240
1241 ret = devm_request_irq(&pdev->dev, irq, s3c64xx_spi_irq, 0,
1242 "spi-s3c64xx", sdd);
1243 if (ret != 0) {
1244 dev_err(&pdev->dev, "Failed to request IRQ %d: %d\n",
1245 irq, ret);
1246 goto err_pm_put;
1247 }
1248
1249 writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
1250 S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
1251 sdd->regs + S3C64XX_SPI_INT_EN);
1252
1253 ret = devm_spi_register_master(&pdev->dev, master);
1254 if (ret != 0) {
1255 dev_err(&pdev->dev, "cannot register SPI master: %d\n", ret);
1256 goto err_pm_put;
1257 }
1258
1259 dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d with %d Slaves attached\n",
1260 sdd->port_id, master->num_chipselect);
1261 dev_dbg(&pdev->dev, "\tIOmem=[%pR]\tFIFO %dbytes\n",
1262 mem_res, (FIFO_LVL_MASK(sdd) >> 1) + 1);
1263
1264 pm_runtime_mark_last_busy(&pdev->dev);
1265 pm_runtime_put_autosuspend(&pdev->dev);
1266
1267 return 0;
1268
1269 err_pm_put:
1270 pm_runtime_put_noidle(&pdev->dev);
1271 pm_runtime_disable(&pdev->dev);
1272 pm_runtime_set_suspended(&pdev->dev);
1273
1274 if (!is_polling(sdd))
1275 dma_release_channel(sdd->tx_dma.ch);
1276 err_release_rx_dma:
1277 if (!is_polling(sdd))
1278 dma_release_channel(sdd->rx_dma.ch);
1279 err_disable_io_clk:
1280 clk_disable_unprepare(sdd->ioclk);
1281 err_disable_src_clk:
1282 clk_disable_unprepare(sdd->src_clk);
1283 err_disable_clk:
1284 clk_disable_unprepare(sdd->clk);
1285 err_deref_master:
1286 spi_master_put(master);
1287
1288 return ret;
1289 }
1290
s3c64xx_spi_remove(struct platform_device * pdev)1291 static int s3c64xx_spi_remove(struct platform_device *pdev)
1292 {
1293 struct spi_master *master = platform_get_drvdata(pdev);
1294 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1295
1296 pm_runtime_get_sync(&pdev->dev);
1297
1298 writel(0, sdd->regs + S3C64XX_SPI_INT_EN);
1299
1300 if (!is_polling(sdd)) {
1301 dma_release_channel(sdd->rx_dma.ch);
1302 dma_release_channel(sdd->tx_dma.ch);
1303 }
1304
1305 clk_disable_unprepare(sdd->ioclk);
1306
1307 clk_disable_unprepare(sdd->src_clk);
1308
1309 clk_disable_unprepare(sdd->clk);
1310
1311 pm_runtime_put_noidle(&pdev->dev);
1312 pm_runtime_disable(&pdev->dev);
1313 pm_runtime_set_suspended(&pdev->dev);
1314
1315 return 0;
1316 }
1317
1318 #ifdef CONFIG_PM_SLEEP
s3c64xx_spi_suspend(struct device * dev)1319 static int s3c64xx_spi_suspend(struct device *dev)
1320 {
1321 struct spi_master *master = dev_get_drvdata(dev);
1322 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1323
1324 int ret = spi_master_suspend(master);
1325 if (ret)
1326 return ret;
1327
1328 ret = pm_runtime_force_suspend(dev);
1329 if (ret < 0)
1330 return ret;
1331
1332 sdd->cur_speed = 0; /* Output Clock is stopped */
1333
1334 return 0;
1335 }
1336
s3c64xx_spi_resume(struct device * dev)1337 static int s3c64xx_spi_resume(struct device *dev)
1338 {
1339 struct spi_master *master = dev_get_drvdata(dev);
1340 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1341 struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1342 int ret;
1343
1344 if (sci->cfg_gpio)
1345 sci->cfg_gpio();
1346
1347 ret = pm_runtime_force_resume(dev);
1348 if (ret < 0)
1349 return ret;
1350
1351 return spi_master_resume(master);
1352 }
1353 #endif /* CONFIG_PM_SLEEP */
1354
1355 #ifdef CONFIG_PM
s3c64xx_spi_runtime_suspend(struct device * dev)1356 static int s3c64xx_spi_runtime_suspend(struct device *dev)
1357 {
1358 struct spi_master *master = dev_get_drvdata(dev);
1359 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1360
1361 clk_disable_unprepare(sdd->clk);
1362 clk_disable_unprepare(sdd->src_clk);
1363 clk_disable_unprepare(sdd->ioclk);
1364
1365 return 0;
1366 }
1367
s3c64xx_spi_runtime_resume(struct device * dev)1368 static int s3c64xx_spi_runtime_resume(struct device *dev)
1369 {
1370 struct spi_master *master = dev_get_drvdata(dev);
1371 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1372 int ret;
1373
1374 if (sdd->port_conf->clk_ioclk) {
1375 ret = clk_prepare_enable(sdd->ioclk);
1376 if (ret != 0)
1377 return ret;
1378 }
1379
1380 ret = clk_prepare_enable(sdd->src_clk);
1381 if (ret != 0)
1382 goto err_disable_ioclk;
1383
1384 ret = clk_prepare_enable(sdd->clk);
1385 if (ret != 0)
1386 goto err_disable_src_clk;
1387
1388 s3c64xx_spi_hwinit(sdd);
1389
1390 writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
1391 S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
1392 sdd->regs + S3C64XX_SPI_INT_EN);
1393
1394 return 0;
1395
1396 err_disable_src_clk:
1397 clk_disable_unprepare(sdd->src_clk);
1398 err_disable_ioclk:
1399 clk_disable_unprepare(sdd->ioclk);
1400
1401 return ret;
1402 }
1403 #endif /* CONFIG_PM */
1404
1405 static const struct dev_pm_ops s3c64xx_spi_pm = {
1406 SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume)
1407 SET_RUNTIME_PM_OPS(s3c64xx_spi_runtime_suspend,
1408 s3c64xx_spi_runtime_resume, NULL)
1409 };
1410
1411 static struct s3c64xx_spi_port_config s3c2443_spi_port_config = {
1412 .fifo_lvl_mask = { 0x7f },
1413 .rx_lvl_offset = 13,
1414 .tx_st_done = 21,
1415 .high_speed = true,
1416 };
1417
1418 static 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 };
1423
1424 static struct s3c64xx_spi_port_config s5pv210_spi_port_config = {
1425 .fifo_lvl_mask = { 0x1ff, 0x7F },
1426 .rx_lvl_offset = 15,
1427 .tx_st_done = 25,
1428 .high_speed = true,
1429 };
1430
1431 static struct s3c64xx_spi_port_config exynos4_spi_port_config = {
1432 .fifo_lvl_mask = { 0x1ff, 0x7F, 0x7F },
1433 .rx_lvl_offset = 15,
1434 .tx_st_done = 25,
1435 .high_speed = true,
1436 .clk_from_cmu = true,
1437 .quirks = S3C64XX_SPI_QUIRK_CS_AUTO,
1438 };
1439
1440 static struct s3c64xx_spi_port_config exynos7_spi_port_config = {
1441 .fifo_lvl_mask = { 0x1ff, 0x7F, 0x7F, 0x7F, 0x7F, 0x1ff},
1442 .rx_lvl_offset = 15,
1443 .tx_st_done = 25,
1444 .high_speed = true,
1445 .clk_from_cmu = true,
1446 .quirks = S3C64XX_SPI_QUIRK_CS_AUTO,
1447 };
1448
1449 static struct s3c64xx_spi_port_config exynos5433_spi_port_config = {
1450 .fifo_lvl_mask = { 0x1ff, 0x7f, 0x7f, 0x7f, 0x7f, 0x1ff},
1451 .rx_lvl_offset = 15,
1452 .tx_st_done = 25,
1453 .high_speed = true,
1454 .clk_from_cmu = true,
1455 .clk_ioclk = true,
1456 .quirks = S3C64XX_SPI_QUIRK_CS_AUTO,
1457 };
1458
1459 static const struct platform_device_id s3c64xx_spi_driver_ids[] = {
1460 {
1461 .name = "s3c2443-spi",
1462 .driver_data = (kernel_ulong_t)&s3c2443_spi_port_config,
1463 }, {
1464 .name = "s3c6410-spi",
1465 .driver_data = (kernel_ulong_t)&s3c6410_spi_port_config,
1466 },
1467 { },
1468 };
1469
1470 static const struct of_device_id s3c64xx_spi_dt_match[] = {
1471 { .compatible = "samsung,s3c2443-spi",
1472 .data = (void *)&s3c2443_spi_port_config,
1473 },
1474 { .compatible = "samsung,s3c6410-spi",
1475 .data = (void *)&s3c6410_spi_port_config,
1476 },
1477 { .compatible = "samsung,s5pv210-spi",
1478 .data = (void *)&s5pv210_spi_port_config,
1479 },
1480 { .compatible = "samsung,exynos4210-spi",
1481 .data = (void *)&exynos4_spi_port_config,
1482 },
1483 { .compatible = "samsung,exynos7-spi",
1484 .data = (void *)&exynos7_spi_port_config,
1485 },
1486 { .compatible = "samsung,exynos5433-spi",
1487 .data = (void *)&exynos5433_spi_port_config,
1488 },
1489 { },
1490 };
1491 MODULE_DEVICE_TABLE(of, s3c64xx_spi_dt_match);
1492
1493 static struct platform_driver s3c64xx_spi_driver = {
1494 .driver = {
1495 .name = "s3c64xx-spi",
1496 .pm = &s3c64xx_spi_pm,
1497 .of_match_table = of_match_ptr(s3c64xx_spi_dt_match),
1498 },
1499 .probe = s3c64xx_spi_probe,
1500 .remove = s3c64xx_spi_remove,
1501 .id_table = s3c64xx_spi_driver_ids,
1502 };
1503 MODULE_ALIAS("platform:s3c64xx-spi");
1504
1505 module_platform_driver(s3c64xx_spi_driver);
1506
1507 MODULE_AUTHOR("Jaswinder Singh <jassi.brar@samsung.com>");
1508 MODULE_DESCRIPTION("S3C64XX SPI Controller Driver");
1509 MODULE_LICENSE("GPL");
1510