1 /*
2 * SPI bus driver for CSR SiRFprimaII
3 *
4 * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
5 *
6 * Licensed under GPLv2 or later.
7 */
8
9 #include <linux/module.h>
10 #include <linux/kernel.h>
11 #include <linux/slab.h>
12 #include <linux/clk.h>
13 #include <linux/interrupt.h>
14 #include <linux/io.h>
15 #include <linux/of.h>
16 #include <linux/bitops.h>
17 #include <linux/err.h>
18 #include <linux/platform_device.h>
19 #include <linux/of_gpio.h>
20 #include <linux/spi/spi.h>
21 #include <linux/spi/spi_bitbang.h>
22 #include <linux/pinctrl/pinmux.h>
23
24 #define DRIVER_NAME "sirfsoc_spi"
25
26 #define SIRFSOC_SPI_CTRL 0x0000
27 #define SIRFSOC_SPI_CMD 0x0004
28 #define SIRFSOC_SPI_TX_RX_EN 0x0008
29 #define SIRFSOC_SPI_INT_EN 0x000C
30 #define SIRFSOC_SPI_INT_STATUS 0x0010
31 #define SIRFSOC_SPI_TX_DMA_IO_CTRL 0x0100
32 #define SIRFSOC_SPI_TX_DMA_IO_LEN 0x0104
33 #define SIRFSOC_SPI_TXFIFO_CTRL 0x0108
34 #define SIRFSOC_SPI_TXFIFO_LEVEL_CHK 0x010C
35 #define SIRFSOC_SPI_TXFIFO_OP 0x0110
36 #define SIRFSOC_SPI_TXFIFO_STATUS 0x0114
37 #define SIRFSOC_SPI_TXFIFO_DATA 0x0118
38 #define SIRFSOC_SPI_RX_DMA_IO_CTRL 0x0120
39 #define SIRFSOC_SPI_RX_DMA_IO_LEN 0x0124
40 #define SIRFSOC_SPI_RXFIFO_CTRL 0x0128
41 #define SIRFSOC_SPI_RXFIFO_LEVEL_CHK 0x012C
42 #define SIRFSOC_SPI_RXFIFO_OP 0x0130
43 #define SIRFSOC_SPI_RXFIFO_STATUS 0x0134
44 #define SIRFSOC_SPI_RXFIFO_DATA 0x0138
45 #define SIRFSOC_SPI_DUMMY_DELAY_CTL 0x0144
46
47 /* SPI CTRL register defines */
48 #define SIRFSOC_SPI_SLV_MODE BIT(16)
49 #define SIRFSOC_SPI_CMD_MODE BIT(17)
50 #define SIRFSOC_SPI_CS_IO_OUT BIT(18)
51 #define SIRFSOC_SPI_CS_IO_MODE BIT(19)
52 #define SIRFSOC_SPI_CLK_IDLE_STAT BIT(20)
53 #define SIRFSOC_SPI_CS_IDLE_STAT BIT(21)
54 #define SIRFSOC_SPI_TRAN_MSB BIT(22)
55 #define SIRFSOC_SPI_DRV_POS_EDGE BIT(23)
56 #define SIRFSOC_SPI_CS_HOLD_TIME BIT(24)
57 #define SIRFSOC_SPI_CLK_SAMPLE_MODE BIT(25)
58 #define SIRFSOC_SPI_TRAN_DAT_FORMAT_8 (0 << 26)
59 #define SIRFSOC_SPI_TRAN_DAT_FORMAT_12 (1 << 26)
60 #define SIRFSOC_SPI_TRAN_DAT_FORMAT_16 (2 << 26)
61 #define SIRFSOC_SPI_TRAN_DAT_FORMAT_32 (3 << 26)
62 #define SIRFSOC_SPI_CMD_BYTE_NUM(x) ((x & 3) << 28)
63 #define SIRFSOC_SPI_ENA_AUTO_CLR BIT(30)
64 #define SIRFSOC_SPI_MUL_DAT_MODE BIT(31)
65
66 /* Interrupt Enable */
67 #define SIRFSOC_SPI_RX_DONE_INT_EN BIT(0)
68 #define SIRFSOC_SPI_TX_DONE_INT_EN BIT(1)
69 #define SIRFSOC_SPI_RX_OFLOW_INT_EN BIT(2)
70 #define SIRFSOC_SPI_TX_UFLOW_INT_EN BIT(3)
71 #define SIRFSOC_SPI_RX_IO_DMA_INT_EN BIT(4)
72 #define SIRFSOC_SPI_TX_IO_DMA_INT_EN BIT(5)
73 #define SIRFSOC_SPI_RXFIFO_FULL_INT_EN BIT(6)
74 #define SIRFSOC_SPI_TXFIFO_EMPTY_INT_EN BIT(7)
75 #define SIRFSOC_SPI_RXFIFO_THD_INT_EN BIT(8)
76 #define SIRFSOC_SPI_TXFIFO_THD_INT_EN BIT(9)
77 #define SIRFSOC_SPI_FRM_END_INT_EN BIT(10)
78
79 #define SIRFSOC_SPI_INT_MASK_ALL 0x1FFF
80
81 /* Interrupt status */
82 #define SIRFSOC_SPI_RX_DONE BIT(0)
83 #define SIRFSOC_SPI_TX_DONE BIT(1)
84 #define SIRFSOC_SPI_RX_OFLOW BIT(2)
85 #define SIRFSOC_SPI_TX_UFLOW BIT(3)
86 #define SIRFSOC_SPI_RX_FIFO_FULL BIT(6)
87 #define SIRFSOC_SPI_TXFIFO_EMPTY BIT(7)
88 #define SIRFSOC_SPI_RXFIFO_THD_REACH BIT(8)
89 #define SIRFSOC_SPI_TXFIFO_THD_REACH BIT(9)
90 #define SIRFSOC_SPI_FRM_END BIT(10)
91
92 /* TX RX enable */
93 #define SIRFSOC_SPI_RX_EN BIT(0)
94 #define SIRFSOC_SPI_TX_EN BIT(1)
95 #define SIRFSOC_SPI_CMD_TX_EN BIT(2)
96
97 #define SIRFSOC_SPI_IO_MODE_SEL BIT(0)
98 #define SIRFSOC_SPI_RX_DMA_FLUSH BIT(2)
99
100 /* FIFO OPs */
101 #define SIRFSOC_SPI_FIFO_RESET BIT(0)
102 #define SIRFSOC_SPI_FIFO_START BIT(1)
103
104 /* FIFO CTRL */
105 #define SIRFSOC_SPI_FIFO_WIDTH_BYTE (0 << 0)
106 #define SIRFSOC_SPI_FIFO_WIDTH_WORD (1 << 0)
107 #define SIRFSOC_SPI_FIFO_WIDTH_DWORD (2 << 0)
108
109 /* FIFO Status */
110 #define SIRFSOC_SPI_FIFO_LEVEL_MASK 0xFF
111 #define SIRFSOC_SPI_FIFO_FULL BIT(8)
112 #define SIRFSOC_SPI_FIFO_EMPTY BIT(9)
113
114 /* 256 bytes rx/tx FIFO */
115 #define SIRFSOC_SPI_FIFO_SIZE 256
116 #define SIRFSOC_SPI_DAT_FRM_LEN_MAX (64 * 1024)
117
118 #define SIRFSOC_SPI_FIFO_SC(x) ((x) & 0x3F)
119 #define SIRFSOC_SPI_FIFO_LC(x) (((x) & 0x3F) << 10)
120 #define SIRFSOC_SPI_FIFO_HC(x) (((x) & 0x3F) << 20)
121 #define SIRFSOC_SPI_FIFO_THD(x) (((x) & 0xFF) << 2)
122
123 struct sirfsoc_spi {
124 struct spi_bitbang bitbang;
125 struct completion done;
126
127 void __iomem *base;
128 u32 ctrl_freq; /* SPI controller clock speed */
129 struct clk *clk;
130 struct pinmux *pmx;
131
132 /* rx & tx bufs from the spi_transfer */
133 const void *tx;
134 void *rx;
135
136 /* place received word into rx buffer */
137 void (*rx_word) (struct sirfsoc_spi *);
138 /* get word from tx buffer for sending */
139 void (*tx_word) (struct sirfsoc_spi *);
140
141 /* number of words left to be tranmitted/received */
142 unsigned int left_tx_cnt;
143 unsigned int left_rx_cnt;
144
145 /* tasklet to push tx msg into FIFO */
146 struct tasklet_struct tasklet_tx;
147
148 int chipselect[0];
149 };
150
spi_sirfsoc_rx_word_u8(struct sirfsoc_spi * sspi)151 static void spi_sirfsoc_rx_word_u8(struct sirfsoc_spi *sspi)
152 {
153 u32 data;
154 u8 *rx = sspi->rx;
155
156 data = readl(sspi->base + SIRFSOC_SPI_RXFIFO_DATA);
157
158 if (rx) {
159 *rx++ = (u8) data;
160 sspi->rx = rx;
161 }
162
163 sspi->left_rx_cnt--;
164 }
165
spi_sirfsoc_tx_word_u8(struct sirfsoc_spi * sspi)166 static void spi_sirfsoc_tx_word_u8(struct sirfsoc_spi *sspi)
167 {
168 u32 data = 0;
169 const u8 *tx = sspi->tx;
170
171 if (tx) {
172 data = *tx++;
173 sspi->tx = tx;
174 }
175
176 writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA);
177 sspi->left_tx_cnt--;
178 }
179
spi_sirfsoc_rx_word_u16(struct sirfsoc_spi * sspi)180 static void spi_sirfsoc_rx_word_u16(struct sirfsoc_spi *sspi)
181 {
182 u32 data;
183 u16 *rx = sspi->rx;
184
185 data = readl(sspi->base + SIRFSOC_SPI_RXFIFO_DATA);
186
187 if (rx) {
188 *rx++ = (u16) data;
189 sspi->rx = rx;
190 }
191
192 sspi->left_rx_cnt--;
193 }
194
spi_sirfsoc_tx_word_u16(struct sirfsoc_spi * sspi)195 static void spi_sirfsoc_tx_word_u16(struct sirfsoc_spi *sspi)
196 {
197 u32 data = 0;
198 const u16 *tx = sspi->tx;
199
200 if (tx) {
201 data = *tx++;
202 sspi->tx = tx;
203 }
204
205 writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA);
206 sspi->left_tx_cnt--;
207 }
208
spi_sirfsoc_rx_word_u32(struct sirfsoc_spi * sspi)209 static void spi_sirfsoc_rx_word_u32(struct sirfsoc_spi *sspi)
210 {
211 u32 data;
212 u32 *rx = sspi->rx;
213
214 data = readl(sspi->base + SIRFSOC_SPI_RXFIFO_DATA);
215
216 if (rx) {
217 *rx++ = (u32) data;
218 sspi->rx = rx;
219 }
220
221 sspi->left_rx_cnt--;
222
223 }
224
spi_sirfsoc_tx_word_u32(struct sirfsoc_spi * sspi)225 static void spi_sirfsoc_tx_word_u32(struct sirfsoc_spi *sspi)
226 {
227 u32 data = 0;
228 const u32 *tx = sspi->tx;
229
230 if (tx) {
231 data = *tx++;
232 sspi->tx = tx;
233 }
234
235 writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA);
236 sspi->left_tx_cnt--;
237 }
238
spi_sirfsoc_tasklet_tx(unsigned long arg)239 static void spi_sirfsoc_tasklet_tx(unsigned long arg)
240 {
241 struct sirfsoc_spi *sspi = (struct sirfsoc_spi *)arg;
242
243 /* Fill Tx FIFO while there are left words to be transmitted */
244 while (!((readl(sspi->base + SIRFSOC_SPI_TXFIFO_STATUS) &
245 SIRFSOC_SPI_FIFO_FULL)) &&
246 sspi->left_tx_cnt)
247 sspi->tx_word(sspi);
248 }
249
spi_sirfsoc_irq(int irq,void * dev_id)250 static irqreturn_t spi_sirfsoc_irq(int irq, void *dev_id)
251 {
252 struct sirfsoc_spi *sspi = dev_id;
253 u32 spi_stat = readl(sspi->base + SIRFSOC_SPI_INT_STATUS);
254
255 writel(spi_stat, sspi->base + SIRFSOC_SPI_INT_STATUS);
256
257 /* Error Conditions */
258 if (spi_stat & SIRFSOC_SPI_RX_OFLOW ||
259 spi_stat & SIRFSOC_SPI_TX_UFLOW) {
260 complete(&sspi->done);
261 writel(0x0, sspi->base + SIRFSOC_SPI_INT_EN);
262 }
263
264 if (spi_stat & SIRFSOC_SPI_FRM_END) {
265 while (!((readl(sspi->base + SIRFSOC_SPI_RXFIFO_STATUS)
266 & SIRFSOC_SPI_FIFO_EMPTY)) &&
267 sspi->left_rx_cnt)
268 sspi->rx_word(sspi);
269
270 /* Received all words */
271 if ((sspi->left_rx_cnt == 0) && (sspi->left_tx_cnt == 0)) {
272 complete(&sspi->done);
273 writel(0x0, sspi->base + SIRFSOC_SPI_INT_EN);
274 }
275 }
276
277 if (spi_stat & SIRFSOC_SPI_RXFIFO_THD_REACH ||
278 spi_stat & SIRFSOC_SPI_TXFIFO_THD_REACH ||
279 spi_stat & SIRFSOC_SPI_RX_FIFO_FULL ||
280 spi_stat & SIRFSOC_SPI_TXFIFO_EMPTY)
281 tasklet_schedule(&sspi->tasklet_tx);
282
283 return IRQ_HANDLED;
284 }
285
spi_sirfsoc_transfer(struct spi_device * spi,struct spi_transfer * t)286 static int spi_sirfsoc_transfer(struct spi_device *spi, struct spi_transfer *t)
287 {
288 struct sirfsoc_spi *sspi;
289 int timeout = t->len * 10;
290 sspi = spi_master_get_devdata(spi->master);
291
292 sspi->tx = t->tx_buf;
293 sspi->rx = t->rx_buf;
294 sspi->left_tx_cnt = sspi->left_rx_cnt = t->len;
295 INIT_COMPLETION(sspi->done);
296
297 writel(SIRFSOC_SPI_INT_MASK_ALL, sspi->base + SIRFSOC_SPI_INT_STATUS);
298
299 if (t->len == 1) {
300 writel(readl(sspi->base + SIRFSOC_SPI_CTRL) |
301 SIRFSOC_SPI_ENA_AUTO_CLR,
302 sspi->base + SIRFSOC_SPI_CTRL);
303 writel(0, sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN);
304 writel(0, sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN);
305 } else if ((t->len > 1) && (t->len < SIRFSOC_SPI_DAT_FRM_LEN_MAX)) {
306 writel(readl(sspi->base + SIRFSOC_SPI_CTRL) |
307 SIRFSOC_SPI_MUL_DAT_MODE |
308 SIRFSOC_SPI_ENA_AUTO_CLR,
309 sspi->base + SIRFSOC_SPI_CTRL);
310 writel(t->len - 1, sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN);
311 writel(t->len - 1, sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN);
312 } else {
313 writel(readl(sspi->base + SIRFSOC_SPI_CTRL),
314 sspi->base + SIRFSOC_SPI_CTRL);
315 writel(0, sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN);
316 writel(0, sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN);
317 }
318
319 writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
320 writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
321 writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
322 writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
323
324 /* Send the first word to trigger the whole tx/rx process */
325 sspi->tx_word(sspi);
326
327 writel(SIRFSOC_SPI_RX_OFLOW_INT_EN | SIRFSOC_SPI_TX_UFLOW_INT_EN |
328 SIRFSOC_SPI_RXFIFO_THD_INT_EN | SIRFSOC_SPI_TXFIFO_THD_INT_EN |
329 SIRFSOC_SPI_FRM_END_INT_EN | SIRFSOC_SPI_RXFIFO_FULL_INT_EN |
330 SIRFSOC_SPI_TXFIFO_EMPTY_INT_EN, sspi->base + SIRFSOC_SPI_INT_EN);
331 writel(SIRFSOC_SPI_RX_EN | SIRFSOC_SPI_TX_EN, sspi->base + SIRFSOC_SPI_TX_RX_EN);
332
333 if (wait_for_completion_timeout(&sspi->done, timeout) == 0)
334 dev_err(&spi->dev, "transfer timeout\n");
335
336 /* TX, RX FIFO stop */
337 writel(0, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
338 writel(0, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
339 writel(0, sspi->base + SIRFSOC_SPI_TX_RX_EN);
340 writel(0, sspi->base + SIRFSOC_SPI_INT_EN);
341
342 return t->len - sspi->left_rx_cnt;
343 }
344
spi_sirfsoc_chipselect(struct spi_device * spi,int value)345 static void spi_sirfsoc_chipselect(struct spi_device *spi, int value)
346 {
347 struct sirfsoc_spi *sspi = spi_master_get_devdata(spi->master);
348
349 if (sspi->chipselect[spi->chip_select] == 0) {
350 u32 regval = readl(sspi->base + SIRFSOC_SPI_CTRL);
351 regval |= SIRFSOC_SPI_CS_IO_OUT;
352 switch (value) {
353 case BITBANG_CS_ACTIVE:
354 if (spi->mode & SPI_CS_HIGH)
355 regval |= SIRFSOC_SPI_CS_IO_OUT;
356 else
357 regval &= ~SIRFSOC_SPI_CS_IO_OUT;
358 break;
359 case BITBANG_CS_INACTIVE:
360 if (spi->mode & SPI_CS_HIGH)
361 regval &= ~SIRFSOC_SPI_CS_IO_OUT;
362 else
363 regval |= SIRFSOC_SPI_CS_IO_OUT;
364 break;
365 }
366 writel(regval, sspi->base + SIRFSOC_SPI_CTRL);
367 } else {
368 int gpio = sspi->chipselect[spi->chip_select];
369 gpio_direction_output(gpio, spi->mode & SPI_CS_HIGH ? 0 : 1);
370 }
371 }
372
373 static int
spi_sirfsoc_setup_transfer(struct spi_device * spi,struct spi_transfer * t)374 spi_sirfsoc_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
375 {
376 struct sirfsoc_spi *sspi;
377 u8 bits_per_word = 0;
378 int hz = 0;
379 u32 regval;
380 u32 txfifo_ctrl, rxfifo_ctrl;
381 u32 fifo_size = SIRFSOC_SPI_FIFO_SIZE / 4;
382
383 sspi = spi_master_get_devdata(spi->master);
384
385 bits_per_word = t && t->bits_per_word ? t->bits_per_word :
386 spi->bits_per_word;
387 hz = t && t->speed_hz ? t->speed_hz : spi->max_speed_hz;
388
389 /* Enable IO mode for RX, TX */
390 writel(SIRFSOC_SPI_IO_MODE_SEL, sspi->base + SIRFSOC_SPI_TX_DMA_IO_CTRL);
391 writel(SIRFSOC_SPI_IO_MODE_SEL, sspi->base + SIRFSOC_SPI_RX_DMA_IO_CTRL);
392 regval = (sspi->ctrl_freq / (2 * hz)) - 1;
393
394 if (regval > 0xFFFF || regval < 0) {
395 dev_err(&spi->dev, "Speed %d not supported\n", hz);
396 return -EINVAL;
397 }
398
399 switch (bits_per_word) {
400 case 8:
401 regval |= SIRFSOC_SPI_TRAN_DAT_FORMAT_8;
402 sspi->rx_word = spi_sirfsoc_rx_word_u8;
403 sspi->tx_word = spi_sirfsoc_tx_word_u8;
404 txfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) |
405 SIRFSOC_SPI_FIFO_WIDTH_BYTE;
406 rxfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) |
407 SIRFSOC_SPI_FIFO_WIDTH_BYTE;
408 break;
409 case 12:
410 case 16:
411 regval |= (bits_per_word == 12) ? SIRFSOC_SPI_TRAN_DAT_FORMAT_12 :
412 SIRFSOC_SPI_TRAN_DAT_FORMAT_16;
413 sspi->rx_word = spi_sirfsoc_rx_word_u16;
414 sspi->tx_word = spi_sirfsoc_tx_word_u16;
415 txfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) |
416 SIRFSOC_SPI_FIFO_WIDTH_WORD;
417 rxfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) |
418 SIRFSOC_SPI_FIFO_WIDTH_WORD;
419 break;
420 case 32:
421 regval |= SIRFSOC_SPI_TRAN_DAT_FORMAT_32;
422 sspi->rx_word = spi_sirfsoc_rx_word_u32;
423 sspi->tx_word = spi_sirfsoc_tx_word_u32;
424 txfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) |
425 SIRFSOC_SPI_FIFO_WIDTH_DWORD;
426 rxfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) |
427 SIRFSOC_SPI_FIFO_WIDTH_DWORD;
428 break;
429 default:
430 dev_err(&spi->dev, "Bits per word %d not supported\n",
431 bits_per_word);
432 return -EINVAL;
433 }
434
435 if (!(spi->mode & SPI_CS_HIGH))
436 regval |= SIRFSOC_SPI_CS_IDLE_STAT;
437 if (!(spi->mode & SPI_LSB_FIRST))
438 regval |= SIRFSOC_SPI_TRAN_MSB;
439 if (spi->mode & SPI_CPOL)
440 regval |= SIRFSOC_SPI_CLK_IDLE_STAT;
441
442 /*
443 * Data should be driven at least 1/2 cycle before the fetch edge to make
444 * sure that data gets stable at the fetch edge.
445 */
446 if (((spi->mode & SPI_CPOL) && (spi->mode & SPI_CPHA)) ||
447 (!(spi->mode & SPI_CPOL) && !(spi->mode & SPI_CPHA)))
448 regval &= ~SIRFSOC_SPI_DRV_POS_EDGE;
449 else
450 regval |= SIRFSOC_SPI_DRV_POS_EDGE;
451
452 writel(SIRFSOC_SPI_FIFO_SC(fifo_size - 2) |
453 SIRFSOC_SPI_FIFO_LC(fifo_size / 2) |
454 SIRFSOC_SPI_FIFO_HC(2),
455 sspi->base + SIRFSOC_SPI_TXFIFO_LEVEL_CHK);
456 writel(SIRFSOC_SPI_FIFO_SC(2) |
457 SIRFSOC_SPI_FIFO_LC(fifo_size / 2) |
458 SIRFSOC_SPI_FIFO_HC(fifo_size - 2),
459 sspi->base + SIRFSOC_SPI_RXFIFO_LEVEL_CHK);
460 writel(txfifo_ctrl, sspi->base + SIRFSOC_SPI_TXFIFO_CTRL);
461 writel(rxfifo_ctrl, sspi->base + SIRFSOC_SPI_RXFIFO_CTRL);
462
463 writel(regval, sspi->base + SIRFSOC_SPI_CTRL);
464 return 0;
465 }
466
spi_sirfsoc_setup(struct spi_device * spi)467 static int spi_sirfsoc_setup(struct spi_device *spi)
468 {
469 struct sirfsoc_spi *sspi;
470
471 if (!spi->max_speed_hz)
472 return -EINVAL;
473
474 sspi = spi_master_get_devdata(spi->master);
475
476 if (!spi->bits_per_word)
477 spi->bits_per_word = 8;
478
479 return spi_sirfsoc_setup_transfer(spi, NULL);
480 }
481
spi_sirfsoc_probe(struct platform_device * pdev)482 static int __devinit spi_sirfsoc_probe(struct platform_device *pdev)
483 {
484 struct sirfsoc_spi *sspi;
485 struct spi_master *master;
486 struct resource *mem_res;
487 int num_cs, cs_gpio, irq;
488 int i;
489 int ret;
490
491 ret = of_property_read_u32(pdev->dev.of_node,
492 "sirf,spi-num-chipselects", &num_cs);
493 if (ret < 0) {
494 dev_err(&pdev->dev, "Unable to get chip select number\n");
495 goto err_cs;
496 }
497
498 master = spi_alloc_master(&pdev->dev, sizeof(*sspi) + sizeof(int) * num_cs);
499 if (!master) {
500 dev_err(&pdev->dev, "Unable to allocate SPI master\n");
501 return -ENOMEM;
502 }
503 platform_set_drvdata(pdev, master);
504 sspi = spi_master_get_devdata(master);
505
506 mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
507 if (!mem_res) {
508 dev_err(&pdev->dev, "Unable to get IO resource\n");
509 ret = -ENODEV;
510 goto free_master;
511 }
512 master->num_chipselect = num_cs;
513
514 for (i = 0; i < master->num_chipselect; i++) {
515 cs_gpio = of_get_named_gpio(pdev->dev.of_node, "cs-gpios", i);
516 if (cs_gpio < 0) {
517 dev_err(&pdev->dev, "can't get cs gpio from DT\n");
518 ret = -ENODEV;
519 goto free_master;
520 }
521
522 sspi->chipselect[i] = cs_gpio;
523 if (cs_gpio == 0)
524 continue; /* use cs from spi controller */
525
526 ret = gpio_request(cs_gpio, DRIVER_NAME);
527 if (ret) {
528 while (i > 0) {
529 i--;
530 if (sspi->chipselect[i] > 0)
531 gpio_free(sspi->chipselect[i]);
532 }
533 dev_err(&pdev->dev, "fail to request cs gpios\n");
534 goto free_master;
535 }
536 }
537
538 sspi->base = devm_request_and_ioremap(&pdev->dev, mem_res);
539 if (!sspi->base) {
540 dev_err(&pdev->dev, "IO remap failed!\n");
541 ret = -ENOMEM;
542 goto free_master;
543 }
544
545 irq = platform_get_irq(pdev, 0);
546 if (irq < 0) {
547 ret = -ENXIO;
548 goto free_master;
549 }
550 ret = devm_request_irq(&pdev->dev, irq, spi_sirfsoc_irq, 0,
551 DRIVER_NAME, sspi);
552 if (ret)
553 goto free_master;
554
555 sspi->bitbang.master = spi_master_get(master);
556 sspi->bitbang.chipselect = spi_sirfsoc_chipselect;
557 sspi->bitbang.setup_transfer = spi_sirfsoc_setup_transfer;
558 sspi->bitbang.txrx_bufs = spi_sirfsoc_transfer;
559 sspi->bitbang.master->setup = spi_sirfsoc_setup;
560 master->bus_num = pdev->id;
561 sspi->bitbang.master->dev.of_node = pdev->dev.of_node;
562
563 sspi->pmx = pinmux_get(&pdev->dev, NULL);
564 ret = IS_ERR(sspi->pmx);
565 if (ret)
566 goto free_master;
567
568 pinmux_enable(sspi->pmx);
569
570 sspi->clk = clk_get(&pdev->dev, NULL);
571 if (IS_ERR(sspi->clk)) {
572 ret = -EINVAL;
573 goto free_pmx;
574 }
575 clk_enable(sspi->clk);
576 sspi->ctrl_freq = clk_get_rate(sspi->clk);
577
578 init_completion(&sspi->done);
579
580 tasklet_init(&sspi->tasklet_tx, spi_sirfsoc_tasklet_tx,
581 (unsigned long)sspi);
582
583 writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
584 writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
585 writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
586 writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
587 /* We are not using dummy delay between command and data */
588 writel(0, sspi->base + SIRFSOC_SPI_DUMMY_DELAY_CTL);
589
590 ret = spi_bitbang_start(&sspi->bitbang);
591 if (ret)
592 goto free_clk;
593
594 dev_info(&pdev->dev, "registerred, bus number = %d\n", master->bus_num);
595
596 return 0;
597
598 free_clk:
599 clk_disable(sspi->clk);
600 clk_put(sspi->clk);
601 free_pmx:
602 pinmux_disable(sspi->pmx);
603 pinmux_put(sspi->pmx);
604 free_master:
605 spi_master_put(master);
606 err_cs:
607 return ret;
608 }
609
spi_sirfsoc_remove(struct platform_device * pdev)610 static int __devexit spi_sirfsoc_remove(struct platform_device *pdev)
611 {
612 struct spi_master *master;
613 struct sirfsoc_spi *sspi;
614 int i;
615
616 master = platform_get_drvdata(pdev);
617 sspi = spi_master_get_devdata(master);
618
619 spi_bitbang_stop(&sspi->bitbang);
620 for (i = 0; i < master->num_chipselect; i++) {
621 if (sspi->chipselect[i] > 0)
622 gpio_free(sspi->chipselect[i]);
623 }
624 clk_disable(sspi->clk);
625 clk_put(sspi->clk);
626 pinmux_disable(sspi->pmx);
627 pinmux_put(sspi->pmx);
628 spi_master_put(master);
629 return 0;
630 }
631
632 #ifdef CONFIG_PM
spi_sirfsoc_suspend(struct device * dev)633 static int spi_sirfsoc_suspend(struct device *dev)
634 {
635 struct platform_device *pdev = to_platform_device(dev);
636 struct spi_master *master = platform_get_drvdata(pdev);
637 struct sirfsoc_spi *sspi = spi_master_get_devdata(master);
638
639 clk_disable(sspi->clk);
640 return 0;
641 }
642
spi_sirfsoc_resume(struct device * dev)643 static int spi_sirfsoc_resume(struct device *dev)
644 {
645 struct platform_device *pdev = to_platform_device(dev);
646 struct spi_master *master = platform_get_drvdata(pdev);
647 struct sirfsoc_spi *sspi = spi_master_get_devdata(master);
648
649 clk_enable(sspi->clk);
650 writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
651 writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
652 writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
653 writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
654
655 return 0;
656 }
657
658 static const struct dev_pm_ops spi_sirfsoc_pm_ops = {
659 .suspend = spi_sirfsoc_suspend,
660 .resume = spi_sirfsoc_resume,
661 };
662 #endif
663
664 static const struct of_device_id spi_sirfsoc_of_match[] = {
665 { .compatible = "sirf,prima2-spi", },
666 {}
667 };
668 MODULE_DEVICE_TABLE(of, sirfsoc_spi_of_match);
669
670 static struct platform_driver spi_sirfsoc_driver = {
671 .driver = {
672 .name = DRIVER_NAME,
673 .owner = THIS_MODULE,
674 #ifdef CONFIG_PM
675 .pm = &spi_sirfsoc_pm_ops,
676 #endif
677 .of_match_table = spi_sirfsoc_of_match,
678 },
679 .probe = spi_sirfsoc_probe,
680 .remove = __devexit_p(spi_sirfsoc_remove),
681 };
682 module_platform_driver(spi_sirfsoc_driver);
683
684 MODULE_DESCRIPTION("SiRF SoC SPI master driver");
685 MODULE_AUTHOR("Zhiwu Song <Zhiwu.Song@csr.com>, "
686 "Barry Song <Baohua.Song@csr.com>");
687 MODULE_LICENSE("GPL v2");
688