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-rw-r--r--drivers/spi/davinci_spi.c1255
1 files changed, 1255 insertions, 0 deletions
diff --git a/drivers/spi/davinci_spi.c b/drivers/spi/davinci_spi.c
new file mode 100644
index 000000000000..225ab60b02c4
--- /dev/null
+++ b/drivers/spi/davinci_spi.c
@@ -0,0 +1,1255 @@
1/*
2 * Copyright (C) 2009 Texas Instruments.
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17 */
18
19#include <linux/interrupt.h>
20#include <linux/io.h>
21#include <linux/gpio.h>
22#include <linux/module.h>
23#include <linux/delay.h>
24#include <linux/platform_device.h>
25#include <linux/err.h>
26#include <linux/clk.h>
27#include <linux/dma-mapping.h>
28#include <linux/spi/spi.h>
29#include <linux/spi/spi_bitbang.h>
30
31#include <mach/spi.h>
32#include <mach/edma.h>
33
34#define SPI_NO_RESOURCE ((resource_size_t)-1)
35
36#define SPI_MAX_CHIPSELECT 2
37
38#define CS_DEFAULT 0xFF
39
40#define SPI_BUFSIZ (SMP_CACHE_BYTES + 1)
41#define DAVINCI_DMA_DATA_TYPE_S8 0x01
42#define DAVINCI_DMA_DATA_TYPE_S16 0x02
43#define DAVINCI_DMA_DATA_TYPE_S32 0x04
44
45#define SPIFMT_PHASE_MASK BIT(16)
46#define SPIFMT_POLARITY_MASK BIT(17)
47#define SPIFMT_DISTIMER_MASK BIT(18)
48#define SPIFMT_SHIFTDIR_MASK BIT(20)
49#define SPIFMT_WAITENA_MASK BIT(21)
50#define SPIFMT_PARITYENA_MASK BIT(22)
51#define SPIFMT_ODD_PARITY_MASK BIT(23)
52#define SPIFMT_WDELAY_MASK 0x3f000000u
53#define SPIFMT_WDELAY_SHIFT 24
54#define SPIFMT_CHARLEN_MASK 0x0000001Fu
55
56/* SPIGCR1 */
57#define SPIGCR1_SPIENA_MASK 0x01000000u
58
59/* SPIPC0 */
60#define SPIPC0_DIFUN_MASK BIT(11) /* MISO */
61#define SPIPC0_DOFUN_MASK BIT(10) /* MOSI */
62#define SPIPC0_CLKFUN_MASK BIT(9) /* CLK */
63#define SPIPC0_SPIENA_MASK BIT(8) /* nREADY */
64#define SPIPC0_EN1FUN_MASK BIT(1)
65#define SPIPC0_EN0FUN_MASK BIT(0)
66
67#define SPIINT_MASKALL 0x0101035F
68#define SPI_INTLVL_1 0x000001FFu
69#define SPI_INTLVL_0 0x00000000u
70
71/* SPIDAT1 */
72#define SPIDAT1_CSHOLD_SHIFT 28
73#define SPIDAT1_CSNR_SHIFT 16
74#define SPIGCR1_CLKMOD_MASK BIT(1)
75#define SPIGCR1_MASTER_MASK BIT(0)
76#define SPIGCR1_LOOPBACK_MASK BIT(16)
77
78/* SPIBUF */
79#define SPIBUF_TXFULL_MASK BIT(29)
80#define SPIBUF_RXEMPTY_MASK BIT(31)
81
82/* Error Masks */
83#define SPIFLG_DLEN_ERR_MASK BIT(0)
84#define SPIFLG_TIMEOUT_MASK BIT(1)
85#define SPIFLG_PARERR_MASK BIT(2)
86#define SPIFLG_DESYNC_MASK BIT(3)
87#define SPIFLG_BITERR_MASK BIT(4)
88#define SPIFLG_OVRRUN_MASK BIT(6)
89#define SPIFLG_RX_INTR_MASK BIT(8)
90#define SPIFLG_TX_INTR_MASK BIT(9)
91#define SPIFLG_BUF_INIT_ACTIVE_MASK BIT(24)
92#define SPIFLG_MASK (SPIFLG_DLEN_ERR_MASK \
93 | SPIFLG_TIMEOUT_MASK | SPIFLG_PARERR_MASK \
94 | SPIFLG_DESYNC_MASK | SPIFLG_BITERR_MASK \
95 | SPIFLG_OVRRUN_MASK | SPIFLG_RX_INTR_MASK \
96 | SPIFLG_TX_INTR_MASK \
97 | SPIFLG_BUF_INIT_ACTIVE_MASK)
98
99#define SPIINT_DLEN_ERR_INTR BIT(0)
100#define SPIINT_TIMEOUT_INTR BIT(1)
101#define SPIINT_PARERR_INTR BIT(2)
102#define SPIINT_DESYNC_INTR BIT(3)
103#define SPIINT_BITERR_INTR BIT(4)
104#define SPIINT_OVRRUN_INTR BIT(6)
105#define SPIINT_RX_INTR BIT(8)
106#define SPIINT_TX_INTR BIT(9)
107#define SPIINT_DMA_REQ_EN BIT(16)
108#define SPIINT_ENABLE_HIGHZ BIT(24)
109
110#define SPI_T2CDELAY_SHIFT 16
111#define SPI_C2TDELAY_SHIFT 24
112
113/* SPI Controller registers */
114#define SPIGCR0 0x00
115#define SPIGCR1 0x04
116#define SPIINT 0x08
117#define SPILVL 0x0c
118#define SPIFLG 0x10
119#define SPIPC0 0x14
120#define SPIPC1 0x18
121#define SPIPC2 0x1c
122#define SPIPC3 0x20
123#define SPIPC4 0x24
124#define SPIPC5 0x28
125#define SPIPC6 0x2c
126#define SPIPC7 0x30
127#define SPIPC8 0x34
128#define SPIDAT0 0x38
129#define SPIDAT1 0x3c
130#define SPIBUF 0x40
131#define SPIEMU 0x44
132#define SPIDELAY 0x48
133#define SPIDEF 0x4c
134#define SPIFMT0 0x50
135#define SPIFMT1 0x54
136#define SPIFMT2 0x58
137#define SPIFMT3 0x5c
138#define TGINTVEC0 0x60
139#define TGINTVEC1 0x64
140
141struct davinci_spi_slave {
142 u32 cmd_to_write;
143 u32 clk_ctrl_to_write;
144 u32 bytes_per_word;
145 u8 active_cs;
146};
147
148/* We have 2 DMA channels per CS, one for RX and one for TX */
149struct davinci_spi_dma {
150 int dma_tx_channel;
151 int dma_rx_channel;
152 int dma_tx_sync_dev;
153 int dma_rx_sync_dev;
154 enum dma_event_q eventq;
155
156 struct completion dma_tx_completion;
157 struct completion dma_rx_completion;
158};
159
160/* SPI Controller driver's private data. */
161struct davinci_spi {
162 struct spi_bitbang bitbang;
163 struct clk *clk;
164
165 u8 version;
166 resource_size_t pbase;
167 void __iomem *base;
168 size_t region_size;
169 u32 irq;
170 struct completion done;
171
172 const void *tx;
173 void *rx;
174 u8 *tmp_buf;
175 int count;
176 struct davinci_spi_dma *dma_channels;
177 struct davinci_spi_platform_data *pdata;
178
179 void (*get_rx)(u32 rx_data, struct davinci_spi *);
180 u32 (*get_tx)(struct davinci_spi *);
181
182 struct davinci_spi_slave slave[SPI_MAX_CHIPSELECT];
183};
184
185static unsigned use_dma;
186
187static void davinci_spi_rx_buf_u8(u32 data, struct davinci_spi *davinci_spi)
188{
189 u8 *rx = davinci_spi->rx;
190
191 *rx++ = (u8)data;
192 davinci_spi->rx = rx;
193}
194
195static void davinci_spi_rx_buf_u16(u32 data, struct davinci_spi *davinci_spi)
196{
197 u16 *rx = davinci_spi->rx;
198
199 *rx++ = (u16)data;
200 davinci_spi->rx = rx;
201}
202
203static u32 davinci_spi_tx_buf_u8(struct davinci_spi *davinci_spi)
204{
205 u32 data;
206 const u8 *tx = davinci_spi->tx;
207
208 data = *tx++;
209 davinci_spi->tx = tx;
210 return data;
211}
212
213static u32 davinci_spi_tx_buf_u16(struct davinci_spi *davinci_spi)
214{
215 u32 data;
216 const u16 *tx = davinci_spi->tx;
217
218 data = *tx++;
219 davinci_spi->tx = tx;
220 return data;
221}
222
223static inline void set_io_bits(void __iomem *addr, u32 bits)
224{
225 u32 v = ioread32(addr);
226
227 v |= bits;
228 iowrite32(v, addr);
229}
230
231static inline void clear_io_bits(void __iomem *addr, u32 bits)
232{
233 u32 v = ioread32(addr);
234
235 v &= ~bits;
236 iowrite32(v, addr);
237}
238
239static inline void set_fmt_bits(void __iomem *addr, u32 bits, int cs_num)
240{
241 set_io_bits(addr + SPIFMT0 + (0x4 * cs_num), bits);
242}
243
244static inline void clear_fmt_bits(void __iomem *addr, u32 bits, int cs_num)
245{
246 clear_io_bits(addr + SPIFMT0 + (0x4 * cs_num), bits);
247}
248
249static void davinci_spi_set_dma_req(const struct spi_device *spi, int enable)
250{
251 struct davinci_spi *davinci_spi = spi_master_get_devdata(spi->master);
252
253 if (enable)
254 set_io_bits(davinci_spi->base + SPIINT, SPIINT_DMA_REQ_EN);
255 else
256 clear_io_bits(davinci_spi->base + SPIINT, SPIINT_DMA_REQ_EN);
257}
258
259/*
260 * Interface to control the chip select signal
261 */
262static void davinci_spi_chipselect(struct spi_device *spi, int value)
263{
264 struct davinci_spi *davinci_spi;
265 struct davinci_spi_platform_data *pdata;
266 u32 data1_reg_val = 0;
267
268 davinci_spi = spi_master_get_devdata(spi->master);
269 pdata = davinci_spi->pdata;
270
271 /*
272 * Board specific chip select logic decides the polarity and cs
273 * line for the controller
274 */
275 if (value == BITBANG_CS_INACTIVE) {
276 set_io_bits(davinci_spi->base + SPIDEF, CS_DEFAULT);
277
278 data1_reg_val |= CS_DEFAULT << SPIDAT1_CSNR_SHIFT;
279 iowrite32(data1_reg_val, davinci_spi->base + SPIDAT1);
280
281 while ((ioread32(davinci_spi->base + SPIBUF)
282 & SPIBUF_RXEMPTY_MASK) == 0)
283 cpu_relax();
284 }
285}
286
287/**
288 * davinci_spi_setup_transfer - This functions will determine transfer method
289 * @spi: spi device on which data transfer to be done
290 * @t: spi transfer in which transfer info is filled
291 *
292 * This function determines data transfer method (8/16/32 bit transfer).
293 * It will also set the SPI Clock Control register according to
294 * SPI slave device freq.
295 */
296static int davinci_spi_setup_transfer(struct spi_device *spi,
297 struct spi_transfer *t)
298{
299
300 struct davinci_spi *davinci_spi;
301 struct davinci_spi_platform_data *pdata;
302 u8 bits_per_word = 0;
303 u32 hz = 0, prescale;
304
305 davinci_spi = spi_master_get_devdata(spi->master);
306 pdata = davinci_spi->pdata;
307
308 if (t) {
309 bits_per_word = t->bits_per_word;
310 hz = t->speed_hz;
311 }
312
313 /* if bits_per_word is not set then set it default */
314 if (!bits_per_word)
315 bits_per_word = spi->bits_per_word;
316
317 /*
318 * Assign function pointer to appropriate transfer method
319 * 8bit, 16bit or 32bit transfer
320 */
321 if (bits_per_word <= 8 && bits_per_word >= 2) {
322 davinci_spi->get_rx = davinci_spi_rx_buf_u8;
323 davinci_spi->get_tx = davinci_spi_tx_buf_u8;
324 davinci_spi->slave[spi->chip_select].bytes_per_word = 1;
325 } else if (bits_per_word <= 16 && bits_per_word >= 2) {
326 davinci_spi->get_rx = davinci_spi_rx_buf_u16;
327 davinci_spi->get_tx = davinci_spi_tx_buf_u16;
328 davinci_spi->slave[spi->chip_select].bytes_per_word = 2;
329 } else
330 return -EINVAL;
331
332 if (!hz)
333 hz = spi->max_speed_hz;
334
335 clear_fmt_bits(davinci_spi->base, SPIFMT_CHARLEN_MASK,
336 spi->chip_select);
337 set_fmt_bits(davinci_spi->base, bits_per_word & 0x1f,
338 spi->chip_select);
339
340 prescale = ((clk_get_rate(davinci_spi->clk) / hz) - 1) & 0xff;
341
342 clear_fmt_bits(davinci_spi->base, 0x0000ff00, spi->chip_select);
343 set_fmt_bits(davinci_spi->base, prescale << 8, spi->chip_select);
344
345 return 0;
346}
347
348static void davinci_spi_dma_rx_callback(unsigned lch, u16 ch_status, void *data)
349{
350 struct spi_device *spi = (struct spi_device *)data;
351 struct davinci_spi *davinci_spi;
352 struct davinci_spi_dma *davinci_spi_dma;
353 struct davinci_spi_platform_data *pdata;
354
355 davinci_spi = spi_master_get_devdata(spi->master);
356 davinci_spi_dma = &(davinci_spi->dma_channels[spi->chip_select]);
357 pdata = davinci_spi->pdata;
358
359 if (ch_status == DMA_COMPLETE)
360 edma_stop(davinci_spi_dma->dma_rx_channel);
361 else
362 edma_clean_channel(davinci_spi_dma->dma_rx_channel);
363
364 complete(&davinci_spi_dma->dma_rx_completion);
365 /* We must disable the DMA RX request */
366 davinci_spi_set_dma_req(spi, 0);
367}
368
369static void davinci_spi_dma_tx_callback(unsigned lch, u16 ch_status, void *data)
370{
371 struct spi_device *spi = (struct spi_device *)data;
372 struct davinci_spi *davinci_spi;
373 struct davinci_spi_dma *davinci_spi_dma;
374 struct davinci_spi_platform_data *pdata;
375
376 davinci_spi = spi_master_get_devdata(spi->master);
377 davinci_spi_dma = &(davinci_spi->dma_channels[spi->chip_select]);
378 pdata = davinci_spi->pdata;
379
380 if (ch_status == DMA_COMPLETE)
381 edma_stop(davinci_spi_dma->dma_tx_channel);
382 else
383 edma_clean_channel(davinci_spi_dma->dma_tx_channel);
384
385 complete(&davinci_spi_dma->dma_tx_completion);
386 /* We must disable the DMA TX request */
387 davinci_spi_set_dma_req(spi, 0);
388}
389
390static int davinci_spi_request_dma(struct spi_device *spi)
391{
392 struct davinci_spi *davinci_spi;
393 struct davinci_spi_dma *davinci_spi_dma;
394 struct davinci_spi_platform_data *pdata;
395 struct device *sdev;
396 int r;
397
398 davinci_spi = spi_master_get_devdata(spi->master);
399 davinci_spi_dma = &davinci_spi->dma_channels[spi->chip_select];
400 pdata = davinci_spi->pdata;
401 sdev = davinci_spi->bitbang.master->dev.parent;
402
403 r = edma_alloc_channel(davinci_spi_dma->dma_rx_sync_dev,
404 davinci_spi_dma_rx_callback, spi,
405 davinci_spi_dma->eventq);
406 if (r < 0) {
407 dev_dbg(sdev, "Unable to request DMA channel for SPI RX\n");
408 return -EAGAIN;
409 }
410 davinci_spi_dma->dma_rx_channel = r;
411 r = edma_alloc_channel(davinci_spi_dma->dma_tx_sync_dev,
412 davinci_spi_dma_tx_callback, spi,
413 davinci_spi_dma->eventq);
414 if (r < 0) {
415 edma_free_channel(davinci_spi_dma->dma_rx_channel);
416 davinci_spi_dma->dma_rx_channel = -1;
417 dev_dbg(sdev, "Unable to request DMA channel for SPI TX\n");
418 return -EAGAIN;
419 }
420 davinci_spi_dma->dma_tx_channel = r;
421
422 return 0;
423}
424
425/**
426 * davinci_spi_setup - This functions will set default transfer method
427 * @spi: spi device on which data transfer to be done
428 *
429 * This functions sets the default transfer method.
430 */
431
432static int davinci_spi_setup(struct spi_device *spi)
433{
434 int retval;
435 struct davinci_spi *davinci_spi;
436 struct davinci_spi_dma *davinci_spi_dma;
437 struct device *sdev;
438
439 davinci_spi = spi_master_get_devdata(spi->master);
440 sdev = davinci_spi->bitbang.master->dev.parent;
441
442 /* if bits per word length is zero then set it default 8 */
443 if (!spi->bits_per_word)
444 spi->bits_per_word = 8;
445
446 davinci_spi->slave[spi->chip_select].cmd_to_write = 0;
447
448 if (use_dma && davinci_spi->dma_channels) {
449 davinci_spi_dma = &davinci_spi->dma_channels[spi->chip_select];
450
451 if ((davinci_spi_dma->dma_rx_channel == -1)
452 || (davinci_spi_dma->dma_tx_channel == -1)) {
453 retval = davinci_spi_request_dma(spi);
454 if (retval < 0)
455 return retval;
456 }
457 }
458
459 /*
460 * SPI in DaVinci and DA8xx operate between
461 * 600 KHz and 50 MHz
462 */
463 if (spi->max_speed_hz < 600000 || spi->max_speed_hz > 50000000) {
464 dev_dbg(sdev, "Operating frequency is not in acceptable "
465 "range\n");
466 return -EINVAL;
467 }
468
469 /*
470 * Set up SPIFMTn register, unique to this chipselect.
471 *
472 * NOTE: we could do all of these with one write. Also, some
473 * of the "version 2" features are found in chips that don't
474 * support all of them...
475 */
476 if (spi->mode & SPI_LSB_FIRST)
477 set_fmt_bits(davinci_spi->base, SPIFMT_SHIFTDIR_MASK,
478 spi->chip_select);
479 else
480 clear_fmt_bits(davinci_spi->base, SPIFMT_SHIFTDIR_MASK,
481 spi->chip_select);
482
483 if (spi->mode & SPI_CPOL)
484 set_fmt_bits(davinci_spi->base, SPIFMT_POLARITY_MASK,
485 spi->chip_select);
486 else
487 clear_fmt_bits(davinci_spi->base, SPIFMT_POLARITY_MASK,
488 spi->chip_select);
489
490 if (!(spi->mode & SPI_CPHA))
491 set_fmt_bits(davinci_spi->base, SPIFMT_PHASE_MASK,
492 spi->chip_select);
493 else
494 clear_fmt_bits(davinci_spi->base, SPIFMT_PHASE_MASK,
495 spi->chip_select);
496
497 /*
498 * Version 1 hardware supports two basic SPI modes:
499 * - Standard SPI mode uses 4 pins, with chipselect
500 * - 3 pin SPI is a 4 pin variant without CS (SPI_NO_CS)
501 * (distinct from SPI_3WIRE, with just one data wire;
502 * or similar variants without MOSI or without MISO)
503 *
504 * Version 2 hardware supports an optional handshaking signal,
505 * so it can support two more modes:
506 * - 5 pin SPI variant is standard SPI plus SPI_READY
507 * - 4 pin with enable is (SPI_READY | SPI_NO_CS)
508 */
509
510 if (davinci_spi->version == SPI_VERSION_2) {
511 clear_fmt_bits(davinci_spi->base, SPIFMT_WDELAY_MASK,
512 spi->chip_select);
513 set_fmt_bits(davinci_spi->base,
514 (davinci_spi->pdata->wdelay
515 << SPIFMT_WDELAY_SHIFT)
516 & SPIFMT_WDELAY_MASK,
517 spi->chip_select);
518
519 if (davinci_spi->pdata->odd_parity)
520 set_fmt_bits(davinci_spi->base,
521 SPIFMT_ODD_PARITY_MASK,
522 spi->chip_select);
523 else
524 clear_fmt_bits(davinci_spi->base,
525 SPIFMT_ODD_PARITY_MASK,
526 spi->chip_select);
527
528 if (davinci_spi->pdata->parity_enable)
529 set_fmt_bits(davinci_spi->base,
530 SPIFMT_PARITYENA_MASK,
531 spi->chip_select);
532 else
533 clear_fmt_bits(davinci_spi->base,
534 SPIFMT_PARITYENA_MASK,
535 spi->chip_select);
536
537 if (davinci_spi->pdata->wait_enable)
538 set_fmt_bits(davinci_spi->base,
539 SPIFMT_WAITENA_MASK,
540 spi->chip_select);
541 else
542 clear_fmt_bits(davinci_spi->base,
543 SPIFMT_WAITENA_MASK,
544 spi->chip_select);
545
546 if (davinci_spi->pdata->timer_disable)
547 set_fmt_bits(davinci_spi->base,
548 SPIFMT_DISTIMER_MASK,
549 spi->chip_select);
550 else
551 clear_fmt_bits(davinci_spi->base,
552 SPIFMT_DISTIMER_MASK,
553 spi->chip_select);
554 }
555
556 retval = davinci_spi_setup_transfer(spi, NULL);
557
558 return retval;
559}
560
561static void davinci_spi_cleanup(struct spi_device *spi)
562{
563 struct davinci_spi *davinci_spi = spi_master_get_devdata(spi->master);
564 struct davinci_spi_dma *davinci_spi_dma;
565
566 davinci_spi_dma = &davinci_spi->dma_channels[spi->chip_select];
567
568 if (use_dma && davinci_spi->dma_channels) {
569 davinci_spi_dma = &davinci_spi->dma_channels[spi->chip_select];
570
571 if ((davinci_spi_dma->dma_rx_channel != -1)
572 && (davinci_spi_dma->dma_tx_channel != -1)) {
573 edma_free_channel(davinci_spi_dma->dma_tx_channel);
574 edma_free_channel(davinci_spi_dma->dma_rx_channel);
575 }
576 }
577}
578
579static int davinci_spi_bufs_prep(struct spi_device *spi,
580 struct davinci_spi *davinci_spi)
581{
582 int op_mode = 0;
583
584 /*
585 * REVISIT unless devices disagree about SPI_LOOP or
586 * SPI_READY (SPI_NO_CS only allows one device!), this
587 * should not need to be done before each message...
588 * optimize for both flags staying cleared.
589 */
590
591 op_mode = SPIPC0_DIFUN_MASK
592 | SPIPC0_DOFUN_MASK
593 | SPIPC0_CLKFUN_MASK;
594 if (!(spi->mode & SPI_NO_CS))
595 op_mode |= 1 << spi->chip_select;
596 if (spi->mode & SPI_READY)
597 op_mode |= SPIPC0_SPIENA_MASK;
598
599 iowrite32(op_mode, davinci_spi->base + SPIPC0);
600
601 if (spi->mode & SPI_LOOP)
602 set_io_bits(davinci_spi->base + SPIGCR1,
603 SPIGCR1_LOOPBACK_MASK);
604 else
605 clear_io_bits(davinci_spi->base + SPIGCR1,
606 SPIGCR1_LOOPBACK_MASK);
607
608 return 0;
609}
610
611static int davinci_spi_check_error(struct davinci_spi *davinci_spi,
612 int int_status)
613{
614 struct device *sdev = davinci_spi->bitbang.master->dev.parent;
615
616 if (int_status & SPIFLG_TIMEOUT_MASK) {
617 dev_dbg(sdev, "SPI Time-out Error\n");
618 return -ETIMEDOUT;
619 }
620 if (int_status & SPIFLG_DESYNC_MASK) {
621 dev_dbg(sdev, "SPI Desynchronization Error\n");
622 return -EIO;
623 }
624 if (int_status & SPIFLG_BITERR_MASK) {
625 dev_dbg(sdev, "SPI Bit error\n");
626 return -EIO;
627 }
628
629 if (davinci_spi->version == SPI_VERSION_2) {
630 if (int_status & SPIFLG_DLEN_ERR_MASK) {
631 dev_dbg(sdev, "SPI Data Length Error\n");
632 return -EIO;
633 }
634 if (int_status & SPIFLG_PARERR_MASK) {
635 dev_dbg(sdev, "SPI Parity Error\n");
636 return -EIO;
637 }
638 if (int_status & SPIFLG_OVRRUN_MASK) {
639 dev_dbg(sdev, "SPI Data Overrun error\n");
640 return -EIO;
641 }
642 if (int_status & SPIFLG_TX_INTR_MASK) {
643 dev_dbg(sdev, "SPI TX intr bit set\n");
644 return -EIO;
645 }
646 if (int_status & SPIFLG_BUF_INIT_ACTIVE_MASK) {
647 dev_dbg(sdev, "SPI Buffer Init Active\n");
648 return -EBUSY;
649 }
650 }
651
652 return 0;
653}
654
655/**
656 * davinci_spi_bufs - functions which will handle transfer data
657 * @spi: spi device on which data transfer to be done
658 * @t: spi transfer in which transfer info is filled
659 *
660 * This function will put data to be transferred into data register
661 * of SPI controller and then wait until the completion will be marked
662 * by the IRQ Handler.
663 */
664static int davinci_spi_bufs_pio(struct spi_device *spi, struct spi_transfer *t)
665{
666 struct davinci_spi *davinci_spi;
667 int int_status, count, ret;
668 u8 conv, tmp;
669 u32 tx_data, data1_reg_val;
670 u32 buf_val, flg_val;
671 struct davinci_spi_platform_data *pdata;
672
673 davinci_spi = spi_master_get_devdata(spi->master);
674 pdata = davinci_spi->pdata;
675
676 davinci_spi->tx = t->tx_buf;
677 davinci_spi->rx = t->rx_buf;
678
679 /* convert len to words based on bits_per_word */
680 conv = davinci_spi->slave[spi->chip_select].bytes_per_word;
681 davinci_spi->count = t->len / conv;
682
683 INIT_COMPLETION(davinci_spi->done);
684
685 ret = davinci_spi_bufs_prep(spi, davinci_spi);
686 if (ret)
687 return ret;
688
689 /* Enable SPI */
690 set_io_bits(davinci_spi->base + SPIGCR1, SPIGCR1_SPIENA_MASK);
691
692 iowrite32(0 | (pdata->c2tdelay << SPI_C2TDELAY_SHIFT) |
693 (pdata->t2cdelay << SPI_T2CDELAY_SHIFT),
694 davinci_spi->base + SPIDELAY);
695
696 count = davinci_spi->count;
697 data1_reg_val = pdata->cs_hold << SPIDAT1_CSHOLD_SHIFT;
698 tmp = ~(0x1 << spi->chip_select);
699
700 clear_io_bits(davinci_spi->base + SPIDEF, ~tmp);
701
702 data1_reg_val |= tmp << SPIDAT1_CSNR_SHIFT;
703
704 while ((ioread32(davinci_spi->base + SPIBUF)
705 & SPIBUF_RXEMPTY_MASK) == 0)
706 cpu_relax();
707
708 /* Determine the command to execute READ or WRITE */
709 if (t->tx_buf) {
710 clear_io_bits(davinci_spi->base + SPIINT, SPIINT_MASKALL);
711
712 while (1) {
713 tx_data = davinci_spi->get_tx(davinci_spi);
714
715 data1_reg_val &= ~(0xFFFF);
716 data1_reg_val |= (0xFFFF & tx_data);
717
718 buf_val = ioread32(davinci_spi->base + SPIBUF);
719 if ((buf_val & SPIBUF_TXFULL_MASK) == 0) {
720 iowrite32(data1_reg_val,
721 davinci_spi->base + SPIDAT1);
722
723 count--;
724 }
725 while (ioread32(davinci_spi->base + SPIBUF)
726 & SPIBUF_RXEMPTY_MASK)
727 cpu_relax();
728
729 /* getting the returned byte */
730 if (t->rx_buf) {
731 buf_val = ioread32(davinci_spi->base + SPIBUF);
732 davinci_spi->get_rx(buf_val, davinci_spi);
733 }
734 if (count <= 0)
735 break;
736 }
737 } else {
738 if (pdata->poll_mode) {
739 while (1) {
740 /* keeps the serial clock going */
741 if ((ioread32(davinci_spi->base + SPIBUF)
742 & SPIBUF_TXFULL_MASK) == 0)
743 iowrite32(data1_reg_val,
744 davinci_spi->base + SPIDAT1);
745
746 while (ioread32(davinci_spi->base + SPIBUF) &
747 SPIBUF_RXEMPTY_MASK)
748 cpu_relax();
749
750 flg_val = ioread32(davinci_spi->base + SPIFLG);
751 buf_val = ioread32(davinci_spi->base + SPIBUF);
752
753 davinci_spi->get_rx(buf_val, davinci_spi);
754
755 count--;
756 if (count <= 0)
757 break;
758 }
759 } else { /* Receive in Interrupt mode */
760 int i;
761
762 for (i = 0; i < davinci_spi->count; i++) {
763 set_io_bits(davinci_spi->base + SPIINT,
764 SPIINT_BITERR_INTR
765 | SPIINT_OVRRUN_INTR
766 | SPIINT_RX_INTR);
767
768 iowrite32(data1_reg_val,
769 davinci_spi->base + SPIDAT1);
770
771 while (ioread32(davinci_spi->base + SPIINT) &
772 SPIINT_RX_INTR)
773 cpu_relax();
774 }
775 iowrite32((data1_reg_val & 0x0ffcffff),
776 davinci_spi->base + SPIDAT1);
777 }
778 }
779
780 /*
781 * Check for bit error, desync error,parity error,timeout error and
782 * receive overflow errors
783 */
784 int_status = ioread32(davinci_spi->base + SPIFLG);
785
786 ret = davinci_spi_check_error(davinci_spi, int_status);
787 if (ret != 0)
788 return ret;
789
790 /* SPI Framework maintains the count only in bytes so convert back */
791 davinci_spi->count *= conv;
792
793 return t->len;
794}
795
796#define DAVINCI_DMA_DATA_TYPE_S8 0x01
797#define DAVINCI_DMA_DATA_TYPE_S16 0x02
798#define DAVINCI_DMA_DATA_TYPE_S32 0x04
799
800static int davinci_spi_bufs_dma(struct spi_device *spi, struct spi_transfer *t)
801{
802 struct davinci_spi *davinci_spi;
803 int int_status = 0;
804 int count, temp_count;
805 u8 conv = 1;
806 u8 tmp;
807 u32 data1_reg_val;
808 struct davinci_spi_dma *davinci_spi_dma;
809 int word_len, data_type, ret;
810 unsigned long tx_reg, rx_reg;
811 struct davinci_spi_platform_data *pdata;
812 struct device *sdev;
813
814 davinci_spi = spi_master_get_devdata(spi->master);
815 pdata = davinci_spi->pdata;
816 sdev = davinci_spi->bitbang.master->dev.parent;
817
818 davinci_spi_dma = &davinci_spi->dma_channels[spi->chip_select];
819
820 tx_reg = (unsigned long)davinci_spi->pbase + SPIDAT1;
821 rx_reg = (unsigned long)davinci_spi->pbase + SPIBUF;
822
823 davinci_spi->tx = t->tx_buf;
824 davinci_spi->rx = t->rx_buf;
825
826 /* convert len to words based on bits_per_word */
827 conv = davinci_spi->slave[spi->chip_select].bytes_per_word;
828 davinci_spi->count = t->len / conv;
829
830 INIT_COMPLETION(davinci_spi->done);
831
832 init_completion(&davinci_spi_dma->dma_rx_completion);
833 init_completion(&davinci_spi_dma->dma_tx_completion);
834
835 word_len = conv * 8;
836
837 if (word_len <= 8)
838 data_type = DAVINCI_DMA_DATA_TYPE_S8;
839 else if (word_len <= 16)
840 data_type = DAVINCI_DMA_DATA_TYPE_S16;
841 else if (word_len <= 32)
842 data_type = DAVINCI_DMA_DATA_TYPE_S32;
843 else
844 return -EINVAL;
845
846 ret = davinci_spi_bufs_prep(spi, davinci_spi);
847 if (ret)
848 return ret;
849
850 /* Put delay val if required */
851 iowrite32(0 | (pdata->c2tdelay << SPI_C2TDELAY_SHIFT) |
852 (pdata->t2cdelay << SPI_T2CDELAY_SHIFT),
853 davinci_spi->base + SPIDELAY);
854
855 count = davinci_spi->count; /* the number of elements */
856 data1_reg_val = pdata->cs_hold << SPIDAT1_CSHOLD_SHIFT;
857
858 /* CS default = 0xFF */
859 tmp = ~(0x1 << spi->chip_select);
860
861 clear_io_bits(davinci_spi->base + SPIDEF, ~tmp);
862
863 data1_reg_val |= tmp << SPIDAT1_CSNR_SHIFT;
864
865 /* disable all interrupts for dma transfers */
866 clear_io_bits(davinci_spi->base + SPIINT, SPIINT_MASKALL);
867 /* Disable SPI to write configuration bits in SPIDAT */
868 clear_io_bits(davinci_spi->base + SPIGCR1, SPIGCR1_SPIENA_MASK);
869 iowrite32(data1_reg_val, davinci_spi->base + SPIDAT1);
870 /* Enable SPI */
871 set_io_bits(davinci_spi->base + SPIGCR1, SPIGCR1_SPIENA_MASK);
872
873 while ((ioread32(davinci_spi->base + SPIBUF)
874 & SPIBUF_RXEMPTY_MASK) == 0)
875 cpu_relax();
876
877
878 if (t->tx_buf) {
879 t->tx_dma = dma_map_single(&spi->dev, (void *)t->tx_buf, count,
880 DMA_TO_DEVICE);
881 if (dma_mapping_error(&spi->dev, t->tx_dma)) {
882 dev_dbg(sdev, "Unable to DMA map a %d bytes"
883 " TX buffer\n", count);
884 return -ENOMEM;
885 }
886 temp_count = count;
887 } else {
888 /* We need TX clocking for RX transaction */
889 t->tx_dma = dma_map_single(&spi->dev,
890 (void *)davinci_spi->tmp_buf, count + 1,
891 DMA_TO_DEVICE);
892 if (dma_mapping_error(&spi->dev, t->tx_dma)) {
893 dev_dbg(sdev, "Unable to DMA map a %d bytes"
894 " TX tmp buffer\n", count);
895 return -ENOMEM;
896 }
897 temp_count = count + 1;
898 }
899
900 edma_set_transfer_params(davinci_spi_dma->dma_tx_channel,
901 data_type, temp_count, 1, 0, ASYNC);
902 edma_set_dest(davinci_spi_dma->dma_tx_channel, tx_reg, INCR, W8BIT);
903 edma_set_src(davinci_spi_dma->dma_tx_channel, t->tx_dma, INCR, W8BIT);
904 edma_set_src_index(davinci_spi_dma->dma_tx_channel, data_type, 0);
905 edma_set_dest_index(davinci_spi_dma->dma_tx_channel, 0, 0);
906
907 if (t->rx_buf) {
908 /* initiate transaction */
909 iowrite32(data1_reg_val, davinci_spi->base + SPIDAT1);
910
911 t->rx_dma = dma_map_single(&spi->dev, (void *)t->rx_buf, count,
912 DMA_FROM_DEVICE);
913 if (dma_mapping_error(&spi->dev, t->rx_dma)) {
914 dev_dbg(sdev, "Couldn't DMA map a %d bytes RX buffer\n",
915 count);
916 if (t->tx_buf != NULL)
917 dma_unmap_single(NULL, t->tx_dma,
918 count, DMA_TO_DEVICE);
919 return -ENOMEM;
920 }
921 edma_set_transfer_params(davinci_spi_dma->dma_rx_channel,
922 data_type, count, 1, 0, ASYNC);
923 edma_set_src(davinci_spi_dma->dma_rx_channel,
924 rx_reg, INCR, W8BIT);
925 edma_set_dest(davinci_spi_dma->dma_rx_channel,
926 t->rx_dma, INCR, W8BIT);
927 edma_set_src_index(davinci_spi_dma->dma_rx_channel, 0, 0);
928 edma_set_dest_index(davinci_spi_dma->dma_rx_channel,
929 data_type, 0);
930 }
931
932 if ((t->tx_buf) || (t->rx_buf))
933 edma_start(davinci_spi_dma->dma_tx_channel);
934
935 if (t->rx_buf)
936 edma_start(davinci_spi_dma->dma_rx_channel);
937
938 if ((t->rx_buf) || (t->tx_buf))
939 davinci_spi_set_dma_req(spi, 1);
940
941 if (t->tx_buf)
942 wait_for_completion_interruptible(
943 &davinci_spi_dma->dma_tx_completion);
944
945 if (t->rx_buf)
946 wait_for_completion_interruptible(
947 &davinci_spi_dma->dma_rx_completion);
948
949 dma_unmap_single(NULL, t->tx_dma, temp_count, DMA_TO_DEVICE);
950
951 if (t->rx_buf)
952 dma_unmap_single(NULL, t->rx_dma, count, DMA_FROM_DEVICE);
953
954 /*
955 * Check for bit error, desync error,parity error,timeout error and
956 * receive overflow errors
957 */
958 int_status = ioread32(davinci_spi->base + SPIFLG);
959
960 ret = davinci_spi_check_error(davinci_spi, int_status);
961 if (ret != 0)
962 return ret;
963
964 /* SPI Framework maintains the count only in bytes so convert back */
965 davinci_spi->count *= conv;
966
967 return t->len;
968}
969
970/**
971 * davinci_spi_irq - IRQ handler for DaVinci SPI
972 * @irq: IRQ number for this SPI Master
973 * @context_data: structure for SPI Master controller davinci_spi
974 */
975static irqreturn_t davinci_spi_irq(s32 irq, void *context_data)
976{
977 struct davinci_spi *davinci_spi = context_data;
978 u32 int_status, rx_data = 0;
979 irqreturn_t ret = IRQ_NONE;
980
981 int_status = ioread32(davinci_spi->base + SPIFLG);
982
983 while ((int_status & SPIFLG_RX_INTR_MASK)) {
984 if (likely(int_status & SPIFLG_RX_INTR_MASK)) {
985 ret = IRQ_HANDLED;
986
987 rx_data = ioread32(davinci_spi->base + SPIBUF);
988 davinci_spi->get_rx(rx_data, davinci_spi);
989
990 /* Disable Receive Interrupt */
991 iowrite32(~(SPIINT_RX_INTR | SPIINT_TX_INTR),
992 davinci_spi->base + SPIINT);
993 } else
994 (void)davinci_spi_check_error(davinci_spi, int_status);
995
996 int_status = ioread32(davinci_spi->base + SPIFLG);
997 }
998
999 return ret;
1000}
1001
1002/**
1003 * davinci_spi_probe - probe function for SPI Master Controller
1004 * @pdev: platform_device structure which contains plateform specific data
1005 */
1006static int davinci_spi_probe(struct platform_device *pdev)
1007{
1008 struct spi_master *master;
1009 struct davinci_spi *davinci_spi;
1010 struct davinci_spi_platform_data *pdata;
1011 struct resource *r, *mem;
1012 resource_size_t dma_rx_chan = SPI_NO_RESOURCE;
1013 resource_size_t dma_tx_chan = SPI_NO_RESOURCE;
1014 resource_size_t dma_eventq = SPI_NO_RESOURCE;
1015 int i = 0, ret = 0;
1016
1017 pdata = pdev->dev.platform_data;
1018 if (pdata == NULL) {
1019 ret = -ENODEV;
1020 goto err;
1021 }
1022
1023 master = spi_alloc_master(&pdev->dev, sizeof(struct davinci_spi));
1024 if (master == NULL) {
1025 ret = -ENOMEM;
1026 goto err;
1027 }
1028
1029 dev_set_drvdata(&pdev->dev, master);
1030
1031 davinci_spi = spi_master_get_devdata(master);
1032 if (davinci_spi == NULL) {
1033 ret = -ENOENT;
1034 goto free_master;
1035 }
1036
1037 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1038 if (r == NULL) {
1039 ret = -ENOENT;
1040 goto free_master;
1041 }
1042
1043 davinci_spi->pbase = r->start;
1044 davinci_spi->region_size = resource_size(r);
1045 davinci_spi->pdata = pdata;
1046
1047 mem = request_mem_region(r->start, davinci_spi->region_size,
1048 pdev->name);
1049 if (mem == NULL) {
1050 ret = -EBUSY;
1051 goto free_master;
1052 }
1053
1054 davinci_spi->base = (struct davinci_spi_reg __iomem *)
1055 ioremap(r->start, davinci_spi->region_size);
1056 if (davinci_spi->base == NULL) {
1057 ret = -ENOMEM;
1058 goto release_region;
1059 }
1060
1061 davinci_spi->irq = platform_get_irq(pdev, 0);
1062 if (davinci_spi->irq <= 0) {
1063 ret = -EINVAL;
1064 goto unmap_io;
1065 }
1066
1067 ret = request_irq(davinci_spi->irq, davinci_spi_irq, IRQF_DISABLED,
1068 dev_name(&pdev->dev), davinci_spi);
1069 if (ret)
1070 goto unmap_io;
1071
1072 /* Allocate tmp_buf for tx_buf */
1073 davinci_spi->tmp_buf = kzalloc(SPI_BUFSIZ, GFP_KERNEL);
1074 if (davinci_spi->tmp_buf == NULL) {
1075 ret = -ENOMEM;
1076 goto irq_free;
1077 }
1078
1079 davinci_spi->bitbang.master = spi_master_get(master);
1080 if (davinci_spi->bitbang.master == NULL) {
1081 ret = -ENODEV;
1082 goto free_tmp_buf;
1083 }
1084
1085 davinci_spi->clk = clk_get(&pdev->dev, NULL);
1086 if (IS_ERR(davinci_spi->clk)) {
1087 ret = -ENODEV;
1088 goto put_master;
1089 }
1090 clk_enable(davinci_spi->clk);
1091
1092
1093 master->bus_num = pdev->id;
1094 master->num_chipselect = pdata->num_chipselect;
1095 master->setup = davinci_spi_setup;
1096 master->cleanup = davinci_spi_cleanup;
1097
1098 davinci_spi->bitbang.chipselect = davinci_spi_chipselect;
1099 davinci_spi->bitbang.setup_transfer = davinci_spi_setup_transfer;
1100
1101 davinci_spi->version = pdata->version;
1102 use_dma = pdata->use_dma;
1103
1104 davinci_spi->bitbang.flags = SPI_NO_CS | SPI_LSB_FIRST | SPI_LOOP;
1105 if (davinci_spi->version == SPI_VERSION_2)
1106 davinci_spi->bitbang.flags |= SPI_READY;
1107
1108 if (use_dma) {
1109 r = platform_get_resource(pdev, IORESOURCE_DMA, 0);
1110 if (r)
1111 dma_rx_chan = r->start;
1112 r = platform_get_resource(pdev, IORESOURCE_DMA, 1);
1113 if (r)
1114 dma_tx_chan = r->start;
1115 r = platform_get_resource(pdev, IORESOURCE_DMA, 2);
1116 if (r)
1117 dma_eventq = r->start;
1118 }
1119
1120 if (!use_dma ||
1121 dma_rx_chan == SPI_NO_RESOURCE ||
1122 dma_tx_chan == SPI_NO_RESOURCE ||
1123 dma_eventq == SPI_NO_RESOURCE) {
1124 davinci_spi->bitbang.txrx_bufs = davinci_spi_bufs_pio;
1125 use_dma = 0;
1126 } else {
1127 davinci_spi->bitbang.txrx_bufs = davinci_spi_bufs_dma;
1128 davinci_spi->dma_channels = kzalloc(master->num_chipselect
1129 * sizeof(struct davinci_spi_dma), GFP_KERNEL);
1130 if (davinci_spi->dma_channels == NULL) {
1131 ret = -ENOMEM;
1132 goto free_clk;
1133 }
1134
1135 for (i = 0; i < master->num_chipselect; i++) {
1136 davinci_spi->dma_channels[i].dma_rx_channel = -1;
1137 davinci_spi->dma_channels[i].dma_rx_sync_dev =
1138 dma_rx_chan;
1139 davinci_spi->dma_channels[i].dma_tx_channel = -1;
1140 davinci_spi->dma_channels[i].dma_tx_sync_dev =
1141 dma_tx_chan;
1142 davinci_spi->dma_channels[i].eventq = dma_eventq;
1143 }
1144 dev_info(&pdev->dev, "DaVinci SPI driver in EDMA mode\n"
1145 "Using RX channel = %d , TX channel = %d and "
1146 "event queue = %d", dma_rx_chan, dma_tx_chan,
1147 dma_eventq);
1148 }
1149
1150 davinci_spi->get_rx = davinci_spi_rx_buf_u8;
1151 davinci_spi->get_tx = davinci_spi_tx_buf_u8;
1152
1153 init_completion(&davinci_spi->done);
1154
1155 /* Reset In/OUT SPI module */
1156 iowrite32(0, davinci_spi->base + SPIGCR0);
1157 udelay(100);
1158 iowrite32(1, davinci_spi->base + SPIGCR0);
1159
1160 /* Clock internal */
1161 if (davinci_spi->pdata->clk_internal)
1162 set_io_bits(davinci_spi->base + SPIGCR1,
1163 SPIGCR1_CLKMOD_MASK);
1164 else
1165 clear_io_bits(davinci_spi->base + SPIGCR1,
1166 SPIGCR1_CLKMOD_MASK);
1167
1168 /* master mode default */
1169 set_io_bits(davinci_spi->base + SPIGCR1, SPIGCR1_MASTER_MASK);
1170
1171 if (davinci_spi->pdata->intr_level)
1172 iowrite32(SPI_INTLVL_1, davinci_spi->base + SPILVL);
1173 else
1174 iowrite32(SPI_INTLVL_0, davinci_spi->base + SPILVL);
1175
1176 ret = spi_bitbang_start(&davinci_spi->bitbang);
1177 if (ret)
1178 goto free_clk;
1179
1180 dev_info(&pdev->dev, "Controller at 0x%p \n", davinci_spi->base);
1181
1182 if (!pdata->poll_mode)
1183 dev_info(&pdev->dev, "Operating in interrupt mode"
1184 " using IRQ %d\n", davinci_spi->irq);
1185
1186 return ret;
1187
1188free_clk:
1189 clk_disable(davinci_spi->clk);
1190 clk_put(davinci_spi->clk);
1191put_master:
1192 spi_master_put(master);
1193free_tmp_buf:
1194 kfree(davinci_spi->tmp_buf);
1195irq_free:
1196 free_irq(davinci_spi->irq, davinci_spi);
1197unmap_io:
1198 iounmap(davinci_spi->base);
1199release_region:
1200 release_mem_region(davinci_spi->pbase, davinci_spi->region_size);
1201free_master:
1202 kfree(master);
1203err:
1204 return ret;
1205}
1206
1207/**
1208 * davinci_spi_remove - remove function for SPI Master Controller
1209 * @pdev: platform_device structure which contains plateform specific data
1210 *
1211 * This function will do the reverse action of davinci_spi_probe function
1212 * It will free the IRQ and SPI controller's memory region.
1213 * It will also call spi_bitbang_stop to destroy the work queue which was
1214 * created by spi_bitbang_start.
1215 */
1216static int __exit davinci_spi_remove(struct platform_device *pdev)
1217{
1218 struct davinci_spi *davinci_spi;
1219 struct spi_master *master;
1220
1221 master = dev_get_drvdata(&pdev->dev);
1222 davinci_spi = spi_master_get_devdata(master);
1223
1224 spi_bitbang_stop(&davinci_spi->bitbang);
1225
1226 clk_disable(davinci_spi->clk);
1227 clk_put(davinci_spi->clk);
1228 spi_master_put(master);
1229 kfree(davinci_spi->tmp_buf);
1230 free_irq(davinci_spi->irq, davinci_spi);
1231 iounmap(davinci_spi->base);
1232 release_mem_region(davinci_spi->pbase, davinci_spi->region_size);
1233
1234 return 0;
1235}
1236
1237static struct platform_driver davinci_spi_driver = {
1238 .driver.name = "spi_davinci",
1239 .remove = __exit_p(davinci_spi_remove),
1240};
1241
1242static int __init davinci_spi_init(void)
1243{
1244 return platform_driver_probe(&davinci_spi_driver, davinci_spi_probe);
1245}
1246module_init(davinci_spi_init);
1247
1248static void __exit davinci_spi_exit(void)
1249{
1250 platform_driver_unregister(&davinci_spi_driver);
1251}
1252module_exit(davinci_spi_exit);
1253
1254MODULE_DESCRIPTION("TI DaVinci SPI Master Controller Driver");
1255MODULE_LICENSE("GPL");