2 * Copyright (C) 2009 Texas Instruments.
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.
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.
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
19 #include <linux/interrupt.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 #include <linux/slab.h>
33 #include <mach/edma.h>
35 #define SPI_NO_RESOURCE ((resource_size_t)-1)
37 #define SPI_MAX_CHIPSELECT 2
39 #define CS_DEFAULT 0xFF
41 #define SPI_BUFSIZ (SMP_CACHE_BYTES + 1)
42 #define DAVINCI_DMA_DATA_TYPE_S8 0x01
43 #define DAVINCI_DMA_DATA_TYPE_S16 0x02
44 #define DAVINCI_DMA_DATA_TYPE_S32 0x04
46 #define SPIFMT_PHASE_MASK BIT(16)
47 #define SPIFMT_POLARITY_MASK BIT(17)
48 #define SPIFMT_DISTIMER_MASK BIT(18)
49 #define SPIFMT_SHIFTDIR_MASK BIT(20)
50 #define SPIFMT_WAITENA_MASK BIT(21)
51 #define SPIFMT_PARITYENA_MASK BIT(22)
52 #define SPIFMT_ODD_PARITY_MASK BIT(23)
53 #define SPIFMT_WDELAY_MASK 0x3f000000u
54 #define SPIFMT_WDELAY_SHIFT 24
55 #define SPIFMT_CHARLEN_MASK 0x0000001Fu
58 #define SPIGCR1_SPIENA_MASK 0x01000000u
61 #define SPIPC0_DIFUN_MASK BIT(11) /* MISO */
62 #define SPIPC0_DOFUN_MASK BIT(10) /* MOSI */
63 #define SPIPC0_CLKFUN_MASK BIT(9) /* CLK */
64 #define SPIPC0_SPIENA_MASK BIT(8) /* nREADY */
65 #define SPIPC0_EN1FUN_MASK BIT(1)
66 #define SPIPC0_EN0FUN_MASK BIT(0)
68 #define SPIINT_MASKALL 0x0101035F
69 #define SPI_INTLVL_1 0x000001FFu
70 #define SPI_INTLVL_0 0x00000000u
73 #define SPIDAT1_CSHOLD_SHIFT 28
74 #define SPIDAT1_CSNR_SHIFT 16
75 #define SPIGCR1_CLKMOD_MASK BIT(1)
76 #define SPIGCR1_MASTER_MASK BIT(0)
77 #define SPIGCR1_LOOPBACK_MASK BIT(16)
80 #define SPIBUF_TXFULL_MASK BIT(29)
81 #define SPIBUF_RXEMPTY_MASK BIT(31)
84 #define SPIFLG_DLEN_ERR_MASK BIT(0)
85 #define SPIFLG_TIMEOUT_MASK BIT(1)
86 #define SPIFLG_PARERR_MASK BIT(2)
87 #define SPIFLG_DESYNC_MASK BIT(3)
88 #define SPIFLG_BITERR_MASK BIT(4)
89 #define SPIFLG_OVRRUN_MASK BIT(6)
90 #define SPIFLG_RX_INTR_MASK BIT(8)
91 #define SPIFLG_TX_INTR_MASK BIT(9)
92 #define SPIFLG_BUF_INIT_ACTIVE_MASK BIT(24)
93 #define SPIFLG_MASK (SPIFLG_DLEN_ERR_MASK \
94 | SPIFLG_TIMEOUT_MASK | SPIFLG_PARERR_MASK \
95 | SPIFLG_DESYNC_MASK | SPIFLG_BITERR_MASK \
96 | SPIFLG_OVRRUN_MASK | SPIFLG_RX_INTR_MASK \
97 | SPIFLG_TX_INTR_MASK \
98 | SPIFLG_BUF_INIT_ACTIVE_MASK)
100 #define SPIINT_DLEN_ERR_INTR BIT(0)
101 #define SPIINT_TIMEOUT_INTR BIT(1)
102 #define SPIINT_PARERR_INTR BIT(2)
103 #define SPIINT_DESYNC_INTR BIT(3)
104 #define SPIINT_BITERR_INTR BIT(4)
105 #define SPIINT_OVRRUN_INTR BIT(6)
106 #define SPIINT_RX_INTR BIT(8)
107 #define SPIINT_TX_INTR BIT(9)
108 #define SPIINT_DMA_REQ_EN BIT(16)
109 #define SPIINT_ENABLE_HIGHZ BIT(24)
111 #define SPI_T2CDELAY_SHIFT 16
112 #define SPI_C2TDELAY_SHIFT 24
114 /* SPI Controller registers */
133 #define SPIDELAY 0x48
139 #define TGINTVEC0 0x60
140 #define TGINTVEC1 0x64
142 struct davinci_spi_slave
{
144 u32 clk_ctrl_to_write
;
149 /* We have 2 DMA channels per CS, one for RX and one for TX */
150 struct davinci_spi_dma
{
155 enum dma_event_q eventq
;
157 struct completion dma_tx_completion
;
158 struct completion dma_rx_completion
;
161 /* SPI Controller driver's private data. */
163 struct spi_bitbang bitbang
;
167 resource_size_t pbase
;
171 struct completion done
;
177 struct davinci_spi_dma
*dma_channels
;
178 struct davinci_spi_platform_data
*pdata
;
180 void (*get_rx
)(u32 rx_data
, struct davinci_spi
*);
181 u32 (*get_tx
)(struct davinci_spi
*);
183 struct davinci_spi_slave slave
[SPI_MAX_CHIPSELECT
];
186 static unsigned use_dma
;
188 static void davinci_spi_rx_buf_u8(u32 data
, struct davinci_spi
*davinci_spi
)
190 u8
*rx
= davinci_spi
->rx
;
193 davinci_spi
->rx
= rx
;
196 static void davinci_spi_rx_buf_u16(u32 data
, struct davinci_spi
*davinci_spi
)
198 u16
*rx
= davinci_spi
->rx
;
201 davinci_spi
->rx
= rx
;
204 static u32
davinci_spi_tx_buf_u8(struct davinci_spi
*davinci_spi
)
207 const u8
*tx
= davinci_spi
->tx
;
210 davinci_spi
->tx
= tx
;
214 static u32
davinci_spi_tx_buf_u16(struct davinci_spi
*davinci_spi
)
217 const u16
*tx
= davinci_spi
->tx
;
220 davinci_spi
->tx
= tx
;
224 static inline void set_io_bits(void __iomem
*addr
, u32 bits
)
226 u32 v
= ioread32(addr
);
232 static inline void clear_io_bits(void __iomem
*addr
, u32 bits
)
234 u32 v
= ioread32(addr
);
240 static inline void set_fmt_bits(void __iomem
*addr
, u32 bits
, int cs_num
)
242 set_io_bits(addr
+ SPIFMT0
+ (0x4 * cs_num
), bits
);
245 static inline void clear_fmt_bits(void __iomem
*addr
, u32 bits
, int cs_num
)
247 clear_io_bits(addr
+ SPIFMT0
+ (0x4 * cs_num
), bits
);
250 static void davinci_spi_set_dma_req(const struct spi_device
*spi
, int enable
)
252 struct davinci_spi
*davinci_spi
= spi_master_get_devdata(spi
->master
);
255 set_io_bits(davinci_spi
->base
+ SPIINT
, SPIINT_DMA_REQ_EN
);
257 clear_io_bits(davinci_spi
->base
+ SPIINT
, SPIINT_DMA_REQ_EN
);
261 * Interface to control the chip select signal
263 static void davinci_spi_chipselect(struct spi_device
*spi
, int value
)
265 struct davinci_spi
*davinci_spi
;
266 struct davinci_spi_platform_data
*pdata
;
267 u32 data1_reg_val
= 0;
269 davinci_spi
= spi_master_get_devdata(spi
->master
);
270 pdata
= davinci_spi
->pdata
;
273 * Board specific chip select logic decides the polarity and cs
274 * line for the controller
276 if (value
== BITBANG_CS_INACTIVE
) {
277 set_io_bits(davinci_spi
->base
+ SPIDEF
, CS_DEFAULT
);
279 data1_reg_val
|= CS_DEFAULT
<< SPIDAT1_CSNR_SHIFT
;
280 iowrite32(data1_reg_val
, davinci_spi
->base
+ SPIDAT1
);
282 while ((ioread32(davinci_spi
->base
+ SPIBUF
)
283 & SPIBUF_RXEMPTY_MASK
) == 0)
289 * davinci_spi_setup_transfer - This functions will determine transfer method
290 * @spi: spi device on which data transfer to be done
291 * @t: spi transfer in which transfer info is filled
293 * This function determines data transfer method (8/16/32 bit transfer).
294 * It will also set the SPI Clock Control register according to
295 * SPI slave device freq.
297 static int davinci_spi_setup_transfer(struct spi_device
*spi
,
298 struct spi_transfer
*t
)
301 struct davinci_spi
*davinci_spi
;
302 struct davinci_spi_platform_data
*pdata
;
303 u8 bits_per_word
= 0;
304 u32 hz
= 0, prescale
;
306 davinci_spi
= spi_master_get_devdata(spi
->master
);
307 pdata
= davinci_spi
->pdata
;
310 bits_per_word
= t
->bits_per_word
;
314 /* if bits_per_word is not set then set it default */
316 bits_per_word
= spi
->bits_per_word
;
319 * Assign function pointer to appropriate transfer method
320 * 8bit, 16bit or 32bit transfer
322 if (bits_per_word
<= 8 && bits_per_word
>= 2) {
323 davinci_spi
->get_rx
= davinci_spi_rx_buf_u8
;
324 davinci_spi
->get_tx
= davinci_spi_tx_buf_u8
;
325 davinci_spi
->slave
[spi
->chip_select
].bytes_per_word
= 1;
326 } else if (bits_per_word
<= 16 && bits_per_word
>= 2) {
327 davinci_spi
->get_rx
= davinci_spi_rx_buf_u16
;
328 davinci_spi
->get_tx
= davinci_spi_tx_buf_u16
;
329 davinci_spi
->slave
[spi
->chip_select
].bytes_per_word
= 2;
334 hz
= spi
->max_speed_hz
;
336 clear_fmt_bits(davinci_spi
->base
, SPIFMT_CHARLEN_MASK
,
338 set_fmt_bits(davinci_spi
->base
, bits_per_word
& 0x1f,
341 prescale
= ((clk_get_rate(davinci_spi
->clk
) / hz
) - 1) & 0xff;
343 clear_fmt_bits(davinci_spi
->base
, 0x0000ff00, spi
->chip_select
);
344 set_fmt_bits(davinci_spi
->base
, prescale
<< 8, spi
->chip_select
);
349 static void davinci_spi_dma_rx_callback(unsigned lch
, u16 ch_status
, void *data
)
351 struct spi_device
*spi
= (struct spi_device
*)data
;
352 struct davinci_spi
*davinci_spi
;
353 struct davinci_spi_dma
*davinci_spi_dma
;
354 struct davinci_spi_platform_data
*pdata
;
356 davinci_spi
= spi_master_get_devdata(spi
->master
);
357 davinci_spi_dma
= &(davinci_spi
->dma_channels
[spi
->chip_select
]);
358 pdata
= davinci_spi
->pdata
;
360 if (ch_status
== DMA_COMPLETE
)
361 edma_stop(davinci_spi_dma
->dma_rx_channel
);
363 edma_clean_channel(davinci_spi_dma
->dma_rx_channel
);
365 complete(&davinci_spi_dma
->dma_rx_completion
);
366 /* We must disable the DMA RX request */
367 davinci_spi_set_dma_req(spi
, 0);
370 static void davinci_spi_dma_tx_callback(unsigned lch
, u16 ch_status
, void *data
)
372 struct spi_device
*spi
= (struct spi_device
*)data
;
373 struct davinci_spi
*davinci_spi
;
374 struct davinci_spi_dma
*davinci_spi_dma
;
375 struct davinci_spi_platform_data
*pdata
;
377 davinci_spi
= spi_master_get_devdata(spi
->master
);
378 davinci_spi_dma
= &(davinci_spi
->dma_channels
[spi
->chip_select
]);
379 pdata
= davinci_spi
->pdata
;
381 if (ch_status
== DMA_COMPLETE
)
382 edma_stop(davinci_spi_dma
->dma_tx_channel
);
384 edma_clean_channel(davinci_spi_dma
->dma_tx_channel
);
386 complete(&davinci_spi_dma
->dma_tx_completion
);
387 /* We must disable the DMA TX request */
388 davinci_spi_set_dma_req(spi
, 0);
391 static int davinci_spi_request_dma(struct spi_device
*spi
)
393 struct davinci_spi
*davinci_spi
;
394 struct davinci_spi_dma
*davinci_spi_dma
;
395 struct davinci_spi_platform_data
*pdata
;
399 davinci_spi
= spi_master_get_devdata(spi
->master
);
400 davinci_spi_dma
= &davinci_spi
->dma_channels
[spi
->chip_select
];
401 pdata
= davinci_spi
->pdata
;
402 sdev
= davinci_spi
->bitbang
.master
->dev
.parent
;
404 r
= edma_alloc_channel(davinci_spi_dma
->dma_rx_sync_dev
,
405 davinci_spi_dma_rx_callback
, spi
,
406 davinci_spi_dma
->eventq
);
408 dev_dbg(sdev
, "Unable to request DMA channel for SPI RX\n");
411 davinci_spi_dma
->dma_rx_channel
= r
;
412 r
= edma_alloc_channel(davinci_spi_dma
->dma_tx_sync_dev
,
413 davinci_spi_dma_tx_callback
, spi
,
414 davinci_spi_dma
->eventq
);
416 edma_free_channel(davinci_spi_dma
->dma_rx_channel
);
417 davinci_spi_dma
->dma_rx_channel
= -1;
418 dev_dbg(sdev
, "Unable to request DMA channel for SPI TX\n");
421 davinci_spi_dma
->dma_tx_channel
= r
;
427 * davinci_spi_setup - This functions will set default transfer method
428 * @spi: spi device on which data transfer to be done
430 * This functions sets the default transfer method.
433 static int davinci_spi_setup(struct spi_device
*spi
)
436 struct davinci_spi
*davinci_spi
;
437 struct davinci_spi_dma
*davinci_spi_dma
;
440 davinci_spi
= spi_master_get_devdata(spi
->master
);
441 sdev
= davinci_spi
->bitbang
.master
->dev
.parent
;
443 /* if bits per word length is zero then set it default 8 */
444 if (!spi
->bits_per_word
)
445 spi
->bits_per_word
= 8;
447 davinci_spi
->slave
[spi
->chip_select
].cmd_to_write
= 0;
449 if (use_dma
&& davinci_spi
->dma_channels
) {
450 davinci_spi_dma
= &davinci_spi
->dma_channels
[spi
->chip_select
];
452 if ((davinci_spi_dma
->dma_rx_channel
== -1)
453 || (davinci_spi_dma
->dma_tx_channel
== -1)) {
454 retval
= davinci_spi_request_dma(spi
);
461 * SPI in DaVinci and DA8xx operate between
464 if (spi
->max_speed_hz
< 600000 || spi
->max_speed_hz
> 50000000) {
465 dev_dbg(sdev
, "Operating frequency is not in acceptable "
471 * Set up SPIFMTn register, unique to this chipselect.
473 * NOTE: we could do all of these with one write. Also, some
474 * of the "version 2" features are found in chips that don't
475 * support all of them...
477 if (spi
->mode
& SPI_LSB_FIRST
)
478 set_fmt_bits(davinci_spi
->base
, SPIFMT_SHIFTDIR_MASK
,
481 clear_fmt_bits(davinci_spi
->base
, SPIFMT_SHIFTDIR_MASK
,
484 if (spi
->mode
& SPI_CPOL
)
485 set_fmt_bits(davinci_spi
->base
, SPIFMT_POLARITY_MASK
,
488 clear_fmt_bits(davinci_spi
->base
, SPIFMT_POLARITY_MASK
,
491 if (!(spi
->mode
& SPI_CPHA
))
492 set_fmt_bits(davinci_spi
->base
, SPIFMT_PHASE_MASK
,
495 clear_fmt_bits(davinci_spi
->base
, SPIFMT_PHASE_MASK
,
499 * Version 1 hardware supports two basic SPI modes:
500 * - Standard SPI mode uses 4 pins, with chipselect
501 * - 3 pin SPI is a 4 pin variant without CS (SPI_NO_CS)
502 * (distinct from SPI_3WIRE, with just one data wire;
503 * or similar variants without MOSI or without MISO)
505 * Version 2 hardware supports an optional handshaking signal,
506 * so it can support two more modes:
507 * - 5 pin SPI variant is standard SPI plus SPI_READY
508 * - 4 pin with enable is (SPI_READY | SPI_NO_CS)
511 if (davinci_spi
->version
== SPI_VERSION_2
) {
512 clear_fmt_bits(davinci_spi
->base
, SPIFMT_WDELAY_MASK
,
514 set_fmt_bits(davinci_spi
->base
,
515 (davinci_spi
->pdata
->wdelay
516 << SPIFMT_WDELAY_SHIFT
)
517 & SPIFMT_WDELAY_MASK
,
520 if (davinci_spi
->pdata
->odd_parity
)
521 set_fmt_bits(davinci_spi
->base
,
522 SPIFMT_ODD_PARITY_MASK
,
525 clear_fmt_bits(davinci_spi
->base
,
526 SPIFMT_ODD_PARITY_MASK
,
529 if (davinci_spi
->pdata
->parity_enable
)
530 set_fmt_bits(davinci_spi
->base
,
531 SPIFMT_PARITYENA_MASK
,
534 clear_fmt_bits(davinci_spi
->base
,
535 SPIFMT_PARITYENA_MASK
,
538 if (davinci_spi
->pdata
->wait_enable
)
539 set_fmt_bits(davinci_spi
->base
,
543 clear_fmt_bits(davinci_spi
->base
,
547 if (davinci_spi
->pdata
->timer_disable
)
548 set_fmt_bits(davinci_spi
->base
,
549 SPIFMT_DISTIMER_MASK
,
552 clear_fmt_bits(davinci_spi
->base
,
553 SPIFMT_DISTIMER_MASK
,
557 retval
= davinci_spi_setup_transfer(spi
, NULL
);
562 static void davinci_spi_cleanup(struct spi_device
*spi
)
564 struct davinci_spi
*davinci_spi
= spi_master_get_devdata(spi
->master
);
565 struct davinci_spi_dma
*davinci_spi_dma
;
567 davinci_spi_dma
= &davinci_spi
->dma_channels
[spi
->chip_select
];
569 if (use_dma
&& davinci_spi
->dma_channels
) {
570 davinci_spi_dma
= &davinci_spi
->dma_channels
[spi
->chip_select
];
572 if ((davinci_spi_dma
->dma_rx_channel
!= -1)
573 && (davinci_spi_dma
->dma_tx_channel
!= -1)) {
574 edma_free_channel(davinci_spi_dma
->dma_tx_channel
);
575 edma_free_channel(davinci_spi_dma
->dma_rx_channel
);
580 static int davinci_spi_bufs_prep(struct spi_device
*spi
,
581 struct davinci_spi
*davinci_spi
)
586 * REVISIT unless devices disagree about SPI_LOOP or
587 * SPI_READY (SPI_NO_CS only allows one device!), this
588 * should not need to be done before each message...
589 * optimize for both flags staying cleared.
592 op_mode
= SPIPC0_DIFUN_MASK
594 | SPIPC0_CLKFUN_MASK
;
595 if (!(spi
->mode
& SPI_NO_CS
))
596 op_mode
|= 1 << spi
->chip_select
;
597 if (spi
->mode
& SPI_READY
)
598 op_mode
|= SPIPC0_SPIENA_MASK
;
600 iowrite32(op_mode
, davinci_spi
->base
+ SPIPC0
);
602 if (spi
->mode
& SPI_LOOP
)
603 set_io_bits(davinci_spi
->base
+ SPIGCR1
,
604 SPIGCR1_LOOPBACK_MASK
);
606 clear_io_bits(davinci_spi
->base
+ SPIGCR1
,
607 SPIGCR1_LOOPBACK_MASK
);
612 static int davinci_spi_check_error(struct davinci_spi
*davinci_spi
,
615 struct device
*sdev
= davinci_spi
->bitbang
.master
->dev
.parent
;
617 if (int_status
& SPIFLG_TIMEOUT_MASK
) {
618 dev_dbg(sdev
, "SPI Time-out Error\n");
621 if (int_status
& SPIFLG_DESYNC_MASK
) {
622 dev_dbg(sdev
, "SPI Desynchronization Error\n");
625 if (int_status
& SPIFLG_BITERR_MASK
) {
626 dev_dbg(sdev
, "SPI Bit error\n");
630 if (davinci_spi
->version
== SPI_VERSION_2
) {
631 if (int_status
& SPIFLG_DLEN_ERR_MASK
) {
632 dev_dbg(sdev
, "SPI Data Length Error\n");
635 if (int_status
& SPIFLG_PARERR_MASK
) {
636 dev_dbg(sdev
, "SPI Parity Error\n");
639 if (int_status
& SPIFLG_OVRRUN_MASK
) {
640 dev_dbg(sdev
, "SPI Data Overrun error\n");
643 if (int_status
& SPIFLG_TX_INTR_MASK
) {
644 dev_dbg(sdev
, "SPI TX intr bit set\n");
647 if (int_status
& SPIFLG_BUF_INIT_ACTIVE_MASK
) {
648 dev_dbg(sdev
, "SPI Buffer Init Active\n");
657 * davinci_spi_bufs - functions which will handle transfer data
658 * @spi: spi device on which data transfer to be done
659 * @t: spi transfer in which transfer info is filled
661 * This function will put data to be transferred into data register
662 * of SPI controller and then wait until the completion will be marked
663 * by the IRQ Handler.
665 static int davinci_spi_bufs_pio(struct spi_device
*spi
, struct spi_transfer
*t
)
667 struct davinci_spi
*davinci_spi
;
668 int int_status
, count
, ret
;
670 u32 tx_data
, data1_reg_val
;
671 u32 buf_val
, flg_val
;
672 struct davinci_spi_platform_data
*pdata
;
674 davinci_spi
= spi_master_get_devdata(spi
->master
);
675 pdata
= davinci_spi
->pdata
;
677 davinci_spi
->tx
= t
->tx_buf
;
678 davinci_spi
->rx
= t
->rx_buf
;
680 /* convert len to words based on bits_per_word */
681 conv
= davinci_spi
->slave
[spi
->chip_select
].bytes_per_word
;
682 davinci_spi
->count
= t
->len
/ conv
;
684 INIT_COMPLETION(davinci_spi
->done
);
686 ret
= davinci_spi_bufs_prep(spi
, davinci_spi
);
691 set_io_bits(davinci_spi
->base
+ SPIGCR1
, SPIGCR1_SPIENA_MASK
);
693 iowrite32(0 | (pdata
->c2tdelay
<< SPI_C2TDELAY_SHIFT
) |
694 (pdata
->t2cdelay
<< SPI_T2CDELAY_SHIFT
),
695 davinci_spi
->base
+ SPIDELAY
);
697 count
= davinci_spi
->count
;
698 data1_reg_val
= pdata
->cs_hold
<< SPIDAT1_CSHOLD_SHIFT
;
699 tmp
= ~(0x1 << spi
->chip_select
);
701 clear_io_bits(davinci_spi
->base
+ SPIDEF
, ~tmp
);
703 data1_reg_val
|= tmp
<< SPIDAT1_CSNR_SHIFT
;
705 while ((ioread32(davinci_spi
->base
+ SPIBUF
)
706 & SPIBUF_RXEMPTY_MASK
) == 0)
709 /* Determine the command to execute READ or WRITE */
711 clear_io_bits(davinci_spi
->base
+ SPIINT
, SPIINT_MASKALL
);
714 tx_data
= davinci_spi
->get_tx(davinci_spi
);
716 data1_reg_val
&= ~(0xFFFF);
717 data1_reg_val
|= (0xFFFF & tx_data
);
719 buf_val
= ioread32(davinci_spi
->base
+ SPIBUF
);
720 if ((buf_val
& SPIBUF_TXFULL_MASK
) == 0) {
721 iowrite32(data1_reg_val
,
722 davinci_spi
->base
+ SPIDAT1
);
726 while (ioread32(davinci_spi
->base
+ SPIBUF
)
727 & SPIBUF_RXEMPTY_MASK
)
730 /* getting the returned byte */
732 buf_val
= ioread32(davinci_spi
->base
+ SPIBUF
);
733 davinci_spi
->get_rx(buf_val
, davinci_spi
);
739 if (pdata
->poll_mode
) {
741 /* keeps the serial clock going */
742 if ((ioread32(davinci_spi
->base
+ SPIBUF
)
743 & SPIBUF_TXFULL_MASK
) == 0)
744 iowrite32(data1_reg_val
,
745 davinci_spi
->base
+ SPIDAT1
);
747 while (ioread32(davinci_spi
->base
+ SPIBUF
) &
751 flg_val
= ioread32(davinci_spi
->base
+ SPIFLG
);
752 buf_val
= ioread32(davinci_spi
->base
+ SPIBUF
);
754 davinci_spi
->get_rx(buf_val
, davinci_spi
);
760 } else { /* Receive in Interrupt mode */
763 for (i
= 0; i
< davinci_spi
->count
; i
++) {
764 set_io_bits(davinci_spi
->base
+ SPIINT
,
769 iowrite32(data1_reg_val
,
770 davinci_spi
->base
+ SPIDAT1
);
772 while (ioread32(davinci_spi
->base
+ SPIINT
) &
776 iowrite32((data1_reg_val
& 0x0ffcffff),
777 davinci_spi
->base
+ SPIDAT1
);
782 * Check for bit error, desync error,parity error,timeout error and
783 * receive overflow errors
785 int_status
= ioread32(davinci_spi
->base
+ SPIFLG
);
787 ret
= davinci_spi_check_error(davinci_spi
, int_status
);
791 /* SPI Framework maintains the count only in bytes so convert back */
792 davinci_spi
->count
*= conv
;
797 #define DAVINCI_DMA_DATA_TYPE_S8 0x01
798 #define DAVINCI_DMA_DATA_TYPE_S16 0x02
799 #define DAVINCI_DMA_DATA_TYPE_S32 0x04
801 static int davinci_spi_bufs_dma(struct spi_device
*spi
, struct spi_transfer
*t
)
803 struct davinci_spi
*davinci_spi
;
805 int count
, temp_count
;
809 struct davinci_spi_dma
*davinci_spi_dma
;
810 int word_len
, data_type
, ret
;
811 unsigned long tx_reg
, rx_reg
;
812 struct davinci_spi_platform_data
*pdata
;
815 davinci_spi
= spi_master_get_devdata(spi
->master
);
816 pdata
= davinci_spi
->pdata
;
817 sdev
= davinci_spi
->bitbang
.master
->dev
.parent
;
819 davinci_spi_dma
= &davinci_spi
->dma_channels
[spi
->chip_select
];
821 tx_reg
= (unsigned long)davinci_spi
->pbase
+ SPIDAT1
;
822 rx_reg
= (unsigned long)davinci_spi
->pbase
+ SPIBUF
;
824 davinci_spi
->tx
= t
->tx_buf
;
825 davinci_spi
->rx
= t
->rx_buf
;
827 /* convert len to words based on bits_per_word */
828 conv
= davinci_spi
->slave
[spi
->chip_select
].bytes_per_word
;
829 davinci_spi
->count
= t
->len
/ conv
;
831 INIT_COMPLETION(davinci_spi
->done
);
833 init_completion(&davinci_spi_dma
->dma_rx_completion
);
834 init_completion(&davinci_spi_dma
->dma_tx_completion
);
839 data_type
= DAVINCI_DMA_DATA_TYPE_S8
;
840 else if (word_len
<= 16)
841 data_type
= DAVINCI_DMA_DATA_TYPE_S16
;
842 else if (word_len
<= 32)
843 data_type
= DAVINCI_DMA_DATA_TYPE_S32
;
847 ret
= davinci_spi_bufs_prep(spi
, davinci_spi
);
851 /* Put delay val if required */
852 iowrite32(0 | (pdata
->c2tdelay
<< SPI_C2TDELAY_SHIFT
) |
853 (pdata
->t2cdelay
<< SPI_T2CDELAY_SHIFT
),
854 davinci_spi
->base
+ SPIDELAY
);
856 count
= davinci_spi
->count
; /* the number of elements */
857 data1_reg_val
= pdata
->cs_hold
<< SPIDAT1_CSHOLD_SHIFT
;
859 /* CS default = 0xFF */
860 tmp
= ~(0x1 << spi
->chip_select
);
862 clear_io_bits(davinci_spi
->base
+ SPIDEF
, ~tmp
);
864 data1_reg_val
|= tmp
<< SPIDAT1_CSNR_SHIFT
;
866 /* disable all interrupts for dma transfers */
867 clear_io_bits(davinci_spi
->base
+ SPIINT
, SPIINT_MASKALL
);
868 /* Disable SPI to write configuration bits in SPIDAT */
869 clear_io_bits(davinci_spi
->base
+ SPIGCR1
, SPIGCR1_SPIENA_MASK
);
870 iowrite32(data1_reg_val
, davinci_spi
->base
+ SPIDAT1
);
872 set_io_bits(davinci_spi
->base
+ SPIGCR1
, SPIGCR1_SPIENA_MASK
);
874 while ((ioread32(davinci_spi
->base
+ SPIBUF
)
875 & SPIBUF_RXEMPTY_MASK
) == 0)
880 t
->tx_dma
= dma_map_single(&spi
->dev
, (void *)t
->tx_buf
, count
,
882 if (dma_mapping_error(&spi
->dev
, t
->tx_dma
)) {
883 dev_dbg(sdev
, "Unable to DMA map a %d bytes"
884 " TX buffer\n", count
);
889 /* We need TX clocking for RX transaction */
890 t
->tx_dma
= dma_map_single(&spi
->dev
,
891 (void *)davinci_spi
->tmp_buf
, count
+ 1,
893 if (dma_mapping_error(&spi
->dev
, t
->tx_dma
)) {
894 dev_dbg(sdev
, "Unable to DMA map a %d bytes"
895 " TX tmp buffer\n", count
);
898 temp_count
= count
+ 1;
901 edma_set_transfer_params(davinci_spi_dma
->dma_tx_channel
,
902 data_type
, temp_count
, 1, 0, ASYNC
);
903 edma_set_dest(davinci_spi_dma
->dma_tx_channel
, tx_reg
, INCR
, W8BIT
);
904 edma_set_src(davinci_spi_dma
->dma_tx_channel
, t
->tx_dma
, INCR
, W8BIT
);
905 edma_set_src_index(davinci_spi_dma
->dma_tx_channel
, data_type
, 0);
906 edma_set_dest_index(davinci_spi_dma
->dma_tx_channel
, 0, 0);
909 /* initiate transaction */
910 iowrite32(data1_reg_val
, davinci_spi
->base
+ SPIDAT1
);
912 t
->rx_dma
= dma_map_single(&spi
->dev
, (void *)t
->rx_buf
, count
,
914 if (dma_mapping_error(&spi
->dev
, t
->rx_dma
)) {
915 dev_dbg(sdev
, "Couldn't DMA map a %d bytes RX buffer\n",
917 if (t
->tx_buf
!= NULL
)
918 dma_unmap_single(NULL
, t
->tx_dma
,
919 count
, DMA_TO_DEVICE
);
922 edma_set_transfer_params(davinci_spi_dma
->dma_rx_channel
,
923 data_type
, count
, 1, 0, ASYNC
);
924 edma_set_src(davinci_spi_dma
->dma_rx_channel
,
925 rx_reg
, INCR
, W8BIT
);
926 edma_set_dest(davinci_spi_dma
->dma_rx_channel
,
927 t
->rx_dma
, INCR
, W8BIT
);
928 edma_set_src_index(davinci_spi_dma
->dma_rx_channel
, 0, 0);
929 edma_set_dest_index(davinci_spi_dma
->dma_rx_channel
,
933 if ((t
->tx_buf
) || (t
->rx_buf
))
934 edma_start(davinci_spi_dma
->dma_tx_channel
);
937 edma_start(davinci_spi_dma
->dma_rx_channel
);
939 if ((t
->rx_buf
) || (t
->tx_buf
))
940 davinci_spi_set_dma_req(spi
, 1);
943 wait_for_completion_interruptible(
944 &davinci_spi_dma
->dma_tx_completion
);
947 wait_for_completion_interruptible(
948 &davinci_spi_dma
->dma_rx_completion
);
950 dma_unmap_single(NULL
, t
->tx_dma
, temp_count
, DMA_TO_DEVICE
);
953 dma_unmap_single(NULL
, t
->rx_dma
, count
, DMA_FROM_DEVICE
);
956 * Check for bit error, desync error,parity error,timeout error and
957 * receive overflow errors
959 int_status
= ioread32(davinci_spi
->base
+ SPIFLG
);
961 ret
= davinci_spi_check_error(davinci_spi
, int_status
);
965 /* SPI Framework maintains the count only in bytes so convert back */
966 davinci_spi
->count
*= conv
;
972 * davinci_spi_irq - IRQ handler for DaVinci SPI
973 * @irq: IRQ number for this SPI Master
974 * @context_data: structure for SPI Master controller davinci_spi
976 static irqreturn_t
davinci_spi_irq(s32 irq
, void *context_data
)
978 struct davinci_spi
*davinci_spi
= context_data
;
979 u32 int_status
, rx_data
= 0;
980 irqreturn_t ret
= IRQ_NONE
;
982 int_status
= ioread32(davinci_spi
->base
+ SPIFLG
);
984 while ((int_status
& SPIFLG_RX_INTR_MASK
)) {
985 if (likely(int_status
& SPIFLG_RX_INTR_MASK
)) {
988 rx_data
= ioread32(davinci_spi
->base
+ SPIBUF
);
989 davinci_spi
->get_rx(rx_data
, davinci_spi
);
991 /* Disable Receive Interrupt */
992 iowrite32(~(SPIINT_RX_INTR
| SPIINT_TX_INTR
),
993 davinci_spi
->base
+ SPIINT
);
995 (void)davinci_spi_check_error(davinci_spi
, int_status
);
997 int_status
= ioread32(davinci_spi
->base
+ SPIFLG
);
1004 * davinci_spi_probe - probe function for SPI Master Controller
1005 * @pdev: platform_device structure which contains plateform specific data
1007 static int davinci_spi_probe(struct platform_device
*pdev
)
1009 struct spi_master
*master
;
1010 struct davinci_spi
*davinci_spi
;
1011 struct davinci_spi_platform_data
*pdata
;
1012 struct resource
*r
, *mem
;
1013 resource_size_t dma_rx_chan
= SPI_NO_RESOURCE
;
1014 resource_size_t dma_tx_chan
= SPI_NO_RESOURCE
;
1015 resource_size_t dma_eventq
= SPI_NO_RESOURCE
;
1018 pdata
= pdev
->dev
.platform_data
;
1019 if (pdata
== NULL
) {
1024 master
= spi_alloc_master(&pdev
->dev
, sizeof(struct davinci_spi
));
1025 if (master
== NULL
) {
1030 dev_set_drvdata(&pdev
->dev
, master
);
1032 davinci_spi
= spi_master_get_devdata(master
);
1033 if (davinci_spi
== NULL
) {
1038 r
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
1044 davinci_spi
->pbase
= r
->start
;
1045 davinci_spi
->region_size
= resource_size(r
);
1046 davinci_spi
->pdata
= pdata
;
1048 mem
= request_mem_region(r
->start
, davinci_spi
->region_size
,
1055 davinci_spi
->base
= (struct davinci_spi_reg __iomem
*)
1056 ioremap(r
->start
, davinci_spi
->region_size
);
1057 if (davinci_spi
->base
== NULL
) {
1059 goto release_region
;
1062 davinci_spi
->irq
= platform_get_irq(pdev
, 0);
1063 if (davinci_spi
->irq
<= 0) {
1068 ret
= request_irq(davinci_spi
->irq
, davinci_spi_irq
, IRQF_DISABLED
,
1069 dev_name(&pdev
->dev
), davinci_spi
);
1073 /* Allocate tmp_buf for tx_buf */
1074 davinci_spi
->tmp_buf
= kzalloc(SPI_BUFSIZ
, GFP_KERNEL
);
1075 if (davinci_spi
->tmp_buf
== NULL
) {
1080 davinci_spi
->bitbang
.master
= spi_master_get(master
);
1081 if (davinci_spi
->bitbang
.master
== NULL
) {
1086 davinci_spi
->clk
= clk_get(&pdev
->dev
, NULL
);
1087 if (IS_ERR(davinci_spi
->clk
)) {
1091 clk_enable(davinci_spi
->clk
);
1094 master
->bus_num
= pdev
->id
;
1095 master
->num_chipselect
= pdata
->num_chipselect
;
1096 master
->setup
= davinci_spi_setup
;
1097 master
->cleanup
= davinci_spi_cleanup
;
1099 davinci_spi
->bitbang
.chipselect
= davinci_spi_chipselect
;
1100 davinci_spi
->bitbang
.setup_transfer
= davinci_spi_setup_transfer
;
1102 davinci_spi
->version
= pdata
->version
;
1103 use_dma
= pdata
->use_dma
;
1105 davinci_spi
->bitbang
.flags
= SPI_NO_CS
| SPI_LSB_FIRST
| SPI_LOOP
;
1106 if (davinci_spi
->version
== SPI_VERSION_2
)
1107 davinci_spi
->bitbang
.flags
|= SPI_READY
;
1110 r
= platform_get_resource(pdev
, IORESOURCE_DMA
, 0);
1112 dma_rx_chan
= r
->start
;
1113 r
= platform_get_resource(pdev
, IORESOURCE_DMA
, 1);
1115 dma_tx_chan
= r
->start
;
1116 r
= platform_get_resource(pdev
, IORESOURCE_DMA
, 2);
1118 dma_eventq
= r
->start
;
1122 dma_rx_chan
== SPI_NO_RESOURCE
||
1123 dma_tx_chan
== SPI_NO_RESOURCE
||
1124 dma_eventq
== SPI_NO_RESOURCE
) {
1125 davinci_spi
->bitbang
.txrx_bufs
= davinci_spi_bufs_pio
;
1128 davinci_spi
->bitbang
.txrx_bufs
= davinci_spi_bufs_dma
;
1129 davinci_spi
->dma_channels
= kzalloc(master
->num_chipselect
1130 * sizeof(struct davinci_spi_dma
), GFP_KERNEL
);
1131 if (davinci_spi
->dma_channels
== NULL
) {
1136 for (i
= 0; i
< master
->num_chipselect
; i
++) {
1137 davinci_spi
->dma_channels
[i
].dma_rx_channel
= -1;
1138 davinci_spi
->dma_channels
[i
].dma_rx_sync_dev
=
1140 davinci_spi
->dma_channels
[i
].dma_tx_channel
= -1;
1141 davinci_spi
->dma_channels
[i
].dma_tx_sync_dev
=
1143 davinci_spi
->dma_channels
[i
].eventq
= dma_eventq
;
1145 dev_info(&pdev
->dev
, "DaVinci SPI driver in EDMA mode\n"
1146 "Using RX channel = %d , TX channel = %d and "
1147 "event queue = %d", dma_rx_chan
, dma_tx_chan
,
1151 davinci_spi
->get_rx
= davinci_spi_rx_buf_u8
;
1152 davinci_spi
->get_tx
= davinci_spi_tx_buf_u8
;
1154 init_completion(&davinci_spi
->done
);
1156 /* Reset In/OUT SPI module */
1157 iowrite32(0, davinci_spi
->base
+ SPIGCR0
);
1159 iowrite32(1, davinci_spi
->base
+ SPIGCR0
);
1161 /* Clock internal */
1162 if (davinci_spi
->pdata
->clk_internal
)
1163 set_io_bits(davinci_spi
->base
+ SPIGCR1
,
1164 SPIGCR1_CLKMOD_MASK
);
1166 clear_io_bits(davinci_spi
->base
+ SPIGCR1
,
1167 SPIGCR1_CLKMOD_MASK
);
1169 /* master mode default */
1170 set_io_bits(davinci_spi
->base
+ SPIGCR1
, SPIGCR1_MASTER_MASK
);
1172 if (davinci_spi
->pdata
->intr_level
)
1173 iowrite32(SPI_INTLVL_1
, davinci_spi
->base
+ SPILVL
);
1175 iowrite32(SPI_INTLVL_0
, davinci_spi
->base
+ SPILVL
);
1177 ret
= spi_bitbang_start(&davinci_spi
->bitbang
);
1181 dev_info(&pdev
->dev
, "Controller at 0x%p \n", davinci_spi
->base
);
1183 if (!pdata
->poll_mode
)
1184 dev_info(&pdev
->dev
, "Operating in interrupt mode"
1185 " using IRQ %d\n", davinci_spi
->irq
);
1190 clk_disable(davinci_spi
->clk
);
1191 clk_put(davinci_spi
->clk
);
1193 spi_master_put(master
);
1195 kfree(davinci_spi
->tmp_buf
);
1197 free_irq(davinci_spi
->irq
, davinci_spi
);
1199 iounmap(davinci_spi
->base
);
1201 release_mem_region(davinci_spi
->pbase
, davinci_spi
->region_size
);
1209 * davinci_spi_remove - remove function for SPI Master Controller
1210 * @pdev: platform_device structure which contains plateform specific data
1212 * This function will do the reverse action of davinci_spi_probe function
1213 * It will free the IRQ and SPI controller's memory region.
1214 * It will also call spi_bitbang_stop to destroy the work queue which was
1215 * created by spi_bitbang_start.
1217 static int __exit
davinci_spi_remove(struct platform_device
*pdev
)
1219 struct davinci_spi
*davinci_spi
;
1220 struct spi_master
*master
;
1222 master
= dev_get_drvdata(&pdev
->dev
);
1223 davinci_spi
= spi_master_get_devdata(master
);
1225 spi_bitbang_stop(&davinci_spi
->bitbang
);
1227 clk_disable(davinci_spi
->clk
);
1228 clk_put(davinci_spi
->clk
);
1229 spi_master_put(master
);
1230 kfree(davinci_spi
->tmp_buf
);
1231 free_irq(davinci_spi
->irq
, davinci_spi
);
1232 iounmap(davinci_spi
->base
);
1233 release_mem_region(davinci_spi
->pbase
, davinci_spi
->region_size
);
1238 static struct platform_driver davinci_spi_driver
= {
1239 .driver
.name
= "spi_davinci",
1240 .remove
= __exit_p(davinci_spi_remove
),
1243 static int __init
davinci_spi_init(void)
1245 return platform_driver_probe(&davinci_spi_driver
, davinci_spi_probe
);
1247 module_init(davinci_spi_init
);
1249 static void __exit
davinci_spi_exit(void)
1251 platform_driver_unregister(&davinci_spi_driver
);
1253 module_exit(davinci_spi_exit
);
1255 MODULE_DESCRIPTION("TI DaVinci SPI Master Controller Driver");
1256 MODULE_LICENSE("GPL");