2 * Blackfin On-Chip SPI Driver
4 * Copyright 2004-2010 Analog Devices Inc.
6 * Enter bugs at http://blackfin.uclinux.org/
8 * Licensed under the GPL-2 or later.
11 #include <linux/init.h>
12 #include <linux/module.h>
13 #include <linux/delay.h>
14 #include <linux/device.h>
15 #include <linux/slab.h>
17 #include <linux/ioport.h>
18 #include <linux/irq.h>
19 #include <linux/errno.h>
20 #include <linux/interrupt.h>
21 #include <linux/platform_device.h>
22 #include <linux/dma-mapping.h>
23 #include <linux/spi/spi.h>
24 #include <linux/workqueue.h>
27 #include <asm/portmux.h>
28 #include <asm/bfin5xx_spi.h>
29 #include <asm/cacheflush.h>
31 #define DRV_NAME "bfin-spi"
32 #define DRV_AUTHOR "Bryan Wu, Luke Yang"
33 #define DRV_DESC "Blackfin on-chip SPI Controller Driver"
34 #define DRV_VERSION "1.0"
36 MODULE_AUTHOR(DRV_AUTHOR
);
37 MODULE_DESCRIPTION(DRV_DESC
);
38 MODULE_LICENSE("GPL");
40 #define START_STATE ((void *)0)
41 #define RUNNING_STATE ((void *)1)
42 #define DONE_STATE ((void *)2)
43 #define ERROR_STATE ((void *)-1)
45 struct bfin_spi_master_data
;
47 struct bfin_spi_transfer_ops
{
48 void (*write
) (struct bfin_spi_master_data
*);
49 void (*read
) (struct bfin_spi_master_data
*);
50 void (*duplex
) (struct bfin_spi_master_data
*);
53 struct bfin_spi_master_data
{
54 /* Driver model hookup */
55 struct platform_device
*pdev
;
57 /* SPI framework hookup */
58 struct spi_master
*master
;
60 /* Regs base of SPI controller */
61 struct bfin_spi_regs __iomem
*regs
;
63 /* Pin request list */
67 struct bfin5xx_spi_master
*master_info
;
69 /* Driver message queue */
70 struct workqueue_struct
*workqueue
;
71 struct work_struct pump_messages
;
73 struct list_head queue
;
77 /* Message Transfer pump */
78 struct tasklet_struct pump_transfers
;
80 /* Current message transfer state info */
81 struct spi_message
*cur_msg
;
82 struct spi_transfer
*cur_transfer
;
83 struct bfin_spi_slave_data
*cur_chip
;
108 const struct bfin_spi_transfer_ops
*ops
;
111 struct bfin_spi_slave_data
{
118 u16 cs_chg_udelay
; /* Some devices require > 255usec delay */
121 u8 pio_interrupt
; /* use spi data irq */
122 const struct bfin_spi_transfer_ops
*ops
;
125 static void bfin_spi_enable(struct bfin_spi_master_data
*drv_data
)
127 bfin_write_or(&drv_data
->regs
->ctl
, BIT_CTL_ENABLE
);
130 static void bfin_spi_disable(struct bfin_spi_master_data
*drv_data
)
132 bfin_write_and(&drv_data
->regs
->ctl
, ~BIT_CTL_ENABLE
);
135 /* Caculate the SPI_BAUD register value based on input HZ */
136 static u16
hz_to_spi_baud(u32 speed_hz
)
138 u_long sclk
= get_sclk();
139 u16 spi_baud
= (sclk
/ (2 * speed_hz
));
141 if ((sclk
% (2 * speed_hz
)) > 0)
144 if (spi_baud
< MIN_SPI_BAUD_VAL
)
145 spi_baud
= MIN_SPI_BAUD_VAL
;
150 static int bfin_spi_flush(struct bfin_spi_master_data
*drv_data
)
152 unsigned long limit
= loops_per_jiffy
<< 1;
154 /* wait for stop and clear stat */
155 while (!(bfin_read(&drv_data
->regs
->stat
) & BIT_STAT_SPIF
) && --limit
)
158 bfin_write(&drv_data
->regs
->stat
, BIT_STAT_CLR
);
163 /* Chip select operation functions for cs_change flag */
164 static void bfin_spi_cs_active(struct bfin_spi_master_data
*drv_data
, struct bfin_spi_slave_data
*chip
)
166 if (likely(chip
->chip_select_num
< MAX_CTRL_CS
))
167 bfin_write_and(&drv_data
->regs
->flg
, ~chip
->flag
);
169 gpio_set_value(chip
->cs_gpio
, 0);
172 static void bfin_spi_cs_deactive(struct bfin_spi_master_data
*drv_data
,
173 struct bfin_spi_slave_data
*chip
)
175 if (likely(chip
->chip_select_num
< MAX_CTRL_CS
))
176 bfin_write_or(&drv_data
->regs
->flg
, chip
->flag
);
178 gpio_set_value(chip
->cs_gpio
, 1);
180 /* Move delay here for consistency */
181 if (chip
->cs_chg_udelay
)
182 udelay(chip
->cs_chg_udelay
);
185 /* enable or disable the pin muxed by GPIO and SPI CS to work as SPI CS */
186 static inline void bfin_spi_cs_enable(struct bfin_spi_master_data
*drv_data
,
187 struct bfin_spi_slave_data
*chip
)
189 if (chip
->chip_select_num
< MAX_CTRL_CS
)
190 bfin_write_or(&drv_data
->regs
->flg
, chip
->flag
>> 8);
193 static inline void bfin_spi_cs_disable(struct bfin_spi_master_data
*drv_data
,
194 struct bfin_spi_slave_data
*chip
)
196 if (chip
->chip_select_num
< MAX_CTRL_CS
)
197 bfin_write_and(&drv_data
->regs
->flg
, ~(chip
->flag
>> 8));
200 /* stop controller and re-config current chip*/
201 static void bfin_spi_restore_state(struct bfin_spi_master_data
*drv_data
)
203 struct bfin_spi_slave_data
*chip
= drv_data
->cur_chip
;
205 /* Clear status and disable clock */
206 bfin_write(&drv_data
->regs
->stat
, BIT_STAT_CLR
);
207 bfin_spi_disable(drv_data
);
208 dev_dbg(&drv_data
->pdev
->dev
, "restoring spi ctl state\n");
212 /* Load the registers */
213 bfin_write(&drv_data
->regs
->ctl
, chip
->ctl_reg
);
214 bfin_write(&drv_data
->regs
->baud
, chip
->baud
);
216 bfin_spi_enable(drv_data
);
217 bfin_spi_cs_active(drv_data
, chip
);
220 /* used to kick off transfer in rx mode and read unwanted RX data */
221 static inline void bfin_spi_dummy_read(struct bfin_spi_master_data
*drv_data
)
223 (void) bfin_read(&drv_data
->regs
->rdbr
);
226 static void bfin_spi_u8_writer(struct bfin_spi_master_data
*drv_data
)
228 /* clear RXS (we check for RXS inside the loop) */
229 bfin_spi_dummy_read(drv_data
);
231 while (drv_data
->tx
< drv_data
->tx_end
) {
232 bfin_write(&drv_data
->regs
->tdbr
, (*(u8
*) (drv_data
->tx
++)));
233 /* wait until transfer finished.
234 checking SPIF or TXS may not guarantee transfer completion */
235 while (!(bfin_read(&drv_data
->regs
->stat
) & BIT_STAT_RXS
))
237 /* discard RX data and clear RXS */
238 bfin_spi_dummy_read(drv_data
);
242 static void bfin_spi_u8_reader(struct bfin_spi_master_data
*drv_data
)
244 u16 tx_val
= drv_data
->cur_chip
->idle_tx_val
;
246 /* discard old RX data and clear RXS */
247 bfin_spi_dummy_read(drv_data
);
249 while (drv_data
->rx
< drv_data
->rx_end
) {
250 bfin_write(&drv_data
->regs
->tdbr
, tx_val
);
251 while (!(bfin_read(&drv_data
->regs
->stat
) & BIT_STAT_RXS
))
253 *(u8
*) (drv_data
->rx
++) = bfin_read(&drv_data
->regs
->rdbr
);
257 static void bfin_spi_u8_duplex(struct bfin_spi_master_data
*drv_data
)
259 /* discard old RX data and clear RXS */
260 bfin_spi_dummy_read(drv_data
);
262 while (drv_data
->rx
< drv_data
->rx_end
) {
263 bfin_write(&drv_data
->regs
->tdbr
, (*(u8
*) (drv_data
->tx
++)));
264 while (!(bfin_read(&drv_data
->regs
->stat
) & BIT_STAT_RXS
))
266 *(u8
*) (drv_data
->rx
++) = bfin_read(&drv_data
->regs
->rdbr
);
270 static const struct bfin_spi_transfer_ops bfin_bfin_spi_transfer_ops_u8
= {
271 .write
= bfin_spi_u8_writer
,
272 .read
= bfin_spi_u8_reader
,
273 .duplex
= bfin_spi_u8_duplex
,
276 static void bfin_spi_u16_writer(struct bfin_spi_master_data
*drv_data
)
278 /* clear RXS (we check for RXS inside the loop) */
279 bfin_spi_dummy_read(drv_data
);
281 while (drv_data
->tx
< drv_data
->tx_end
) {
282 bfin_write(&drv_data
->regs
->tdbr
, (*(u16
*) (drv_data
->tx
)));
284 /* wait until transfer finished.
285 checking SPIF or TXS may not guarantee transfer completion */
286 while (!(bfin_read(&drv_data
->regs
->stat
) & BIT_STAT_RXS
))
288 /* discard RX data and clear RXS */
289 bfin_spi_dummy_read(drv_data
);
293 static void bfin_spi_u16_reader(struct bfin_spi_master_data
*drv_data
)
295 u16 tx_val
= drv_data
->cur_chip
->idle_tx_val
;
297 /* discard old RX data and clear RXS */
298 bfin_spi_dummy_read(drv_data
);
300 while (drv_data
->rx
< drv_data
->rx_end
) {
301 bfin_write(&drv_data
->regs
->tdbr
, tx_val
);
302 while (!(bfin_read(&drv_data
->regs
->stat
) & BIT_STAT_RXS
))
304 *(u16
*) (drv_data
->rx
) = bfin_read(&drv_data
->regs
->rdbr
);
309 static void bfin_spi_u16_duplex(struct bfin_spi_master_data
*drv_data
)
311 /* discard old RX data and clear RXS */
312 bfin_spi_dummy_read(drv_data
);
314 while (drv_data
->rx
< drv_data
->rx_end
) {
315 bfin_write(&drv_data
->regs
->tdbr
, (*(u16
*) (drv_data
->tx
)));
317 while (!(bfin_read(&drv_data
->regs
->stat
) & BIT_STAT_RXS
))
319 *(u16
*) (drv_data
->rx
) = bfin_read(&drv_data
->regs
->rdbr
);
324 static const struct bfin_spi_transfer_ops bfin_bfin_spi_transfer_ops_u16
= {
325 .write
= bfin_spi_u16_writer
,
326 .read
= bfin_spi_u16_reader
,
327 .duplex
= bfin_spi_u16_duplex
,
330 /* test if there is more transfer to be done */
331 static void *bfin_spi_next_transfer(struct bfin_spi_master_data
*drv_data
)
333 struct spi_message
*msg
= drv_data
->cur_msg
;
334 struct spi_transfer
*trans
= drv_data
->cur_transfer
;
336 /* Move to next transfer */
337 if (trans
->transfer_list
.next
!= &msg
->transfers
) {
338 drv_data
->cur_transfer
=
339 list_entry(trans
->transfer_list
.next
,
340 struct spi_transfer
, transfer_list
);
341 return RUNNING_STATE
;
347 * caller already set message->status;
348 * dma and pio irqs are blocked give finished message back
350 static void bfin_spi_giveback(struct bfin_spi_master_data
*drv_data
)
352 struct bfin_spi_slave_data
*chip
= drv_data
->cur_chip
;
354 struct spi_message
*msg
;
356 spin_lock_irqsave(&drv_data
->lock
, flags
);
357 msg
= drv_data
->cur_msg
;
358 drv_data
->cur_msg
= NULL
;
359 drv_data
->cur_transfer
= NULL
;
360 drv_data
->cur_chip
= NULL
;
361 queue_work(drv_data
->workqueue
, &drv_data
->pump_messages
);
362 spin_unlock_irqrestore(&drv_data
->lock
, flags
);
366 if (!drv_data
->cs_change
)
367 bfin_spi_cs_deactive(drv_data
, chip
);
369 /* Not stop spi in autobuffer mode */
370 if (drv_data
->tx_dma
!= 0xFFFF)
371 bfin_spi_disable(drv_data
);
374 msg
->complete(msg
->context
);
377 /* spi data irq handler */
378 static irqreturn_t
bfin_spi_pio_irq_handler(int irq
, void *dev_id
)
380 struct bfin_spi_master_data
*drv_data
= dev_id
;
381 struct bfin_spi_slave_data
*chip
= drv_data
->cur_chip
;
382 struct spi_message
*msg
= drv_data
->cur_msg
;
383 int n_bytes
= drv_data
->n_bytes
;
386 /* wait until transfer finished. */
387 while (!(bfin_read(&drv_data
->regs
->stat
) & BIT_STAT_RXS
))
390 if ((drv_data
->tx
&& drv_data
->tx
>= drv_data
->tx_end
) ||
391 (drv_data
->rx
&& drv_data
->rx
>= (drv_data
->rx_end
- n_bytes
))) {
394 dev_dbg(&drv_data
->pdev
->dev
, "last read\n");
395 if (!(n_bytes
% 2)) {
396 u16
*buf
= (u16
*)drv_data
->rx
;
397 for (loop
= 0; loop
< n_bytes
/ 2; loop
++)
398 *buf
++ = bfin_read(&drv_data
->regs
->rdbr
);
400 u8
*buf
= (u8
*)drv_data
->rx
;
401 for (loop
= 0; loop
< n_bytes
; loop
++)
402 *buf
++ = bfin_read(&drv_data
->regs
->rdbr
);
404 drv_data
->rx
+= n_bytes
;
407 msg
->actual_length
+= drv_data
->len_in_bytes
;
408 if (drv_data
->cs_change
)
409 bfin_spi_cs_deactive(drv_data
, chip
);
410 /* Move to next transfer */
411 msg
->state
= bfin_spi_next_transfer(drv_data
);
413 disable_irq_nosync(drv_data
->spi_irq
);
415 /* Schedule transfer tasklet */
416 tasklet_schedule(&drv_data
->pump_transfers
);
420 if (drv_data
->rx
&& drv_data
->tx
) {
422 dev_dbg(&drv_data
->pdev
->dev
, "duplex: write_TDBR\n");
423 if (!(n_bytes
% 2)) {
424 u16
*buf
= (u16
*)drv_data
->rx
;
425 u16
*buf2
= (u16
*)drv_data
->tx
;
426 for (loop
= 0; loop
< n_bytes
/ 2; loop
++) {
427 *buf
++ = bfin_read(&drv_data
->regs
->rdbr
);
428 bfin_write(&drv_data
->regs
->tdbr
, *buf2
++);
431 u8
*buf
= (u8
*)drv_data
->rx
;
432 u8
*buf2
= (u8
*)drv_data
->tx
;
433 for (loop
= 0; loop
< n_bytes
; loop
++) {
434 *buf
++ = bfin_read(&drv_data
->regs
->rdbr
);
435 bfin_write(&drv_data
->regs
->tdbr
, *buf2
++);
438 } else if (drv_data
->rx
) {
440 dev_dbg(&drv_data
->pdev
->dev
, "read: write_TDBR\n");
441 if (!(n_bytes
% 2)) {
442 u16
*buf
= (u16
*)drv_data
->rx
;
443 for (loop
= 0; loop
< n_bytes
/ 2; loop
++) {
444 *buf
++ = bfin_read(&drv_data
->regs
->rdbr
);
445 bfin_write(&drv_data
->regs
->tdbr
, chip
->idle_tx_val
);
448 u8
*buf
= (u8
*)drv_data
->rx
;
449 for (loop
= 0; loop
< n_bytes
; loop
++) {
450 *buf
++ = bfin_read(&drv_data
->regs
->rdbr
);
451 bfin_write(&drv_data
->regs
->tdbr
, chip
->idle_tx_val
);
454 } else if (drv_data
->tx
) {
456 dev_dbg(&drv_data
->pdev
->dev
, "write: write_TDBR\n");
457 if (!(n_bytes
% 2)) {
458 u16
*buf
= (u16
*)drv_data
->tx
;
459 for (loop
= 0; loop
< n_bytes
/ 2; loop
++) {
460 bfin_read(&drv_data
->regs
->rdbr
);
461 bfin_write(&drv_data
->regs
->tdbr
, *buf
++);
464 u8
*buf
= (u8
*)drv_data
->tx
;
465 for (loop
= 0; loop
< n_bytes
; loop
++) {
466 bfin_read(&drv_data
->regs
->rdbr
);
467 bfin_write(&drv_data
->regs
->tdbr
, *buf
++);
473 drv_data
->tx
+= n_bytes
;
475 drv_data
->rx
+= n_bytes
;
480 static irqreturn_t
bfin_spi_dma_irq_handler(int irq
, void *dev_id
)
482 struct bfin_spi_master_data
*drv_data
= dev_id
;
483 struct bfin_spi_slave_data
*chip
= drv_data
->cur_chip
;
484 struct spi_message
*msg
= drv_data
->cur_msg
;
485 unsigned long timeout
;
486 unsigned short dmastat
= get_dma_curr_irqstat(drv_data
->dma_channel
);
487 u16 spistat
= bfin_read(&drv_data
->regs
->stat
);
489 dev_dbg(&drv_data
->pdev
->dev
,
490 "in dma_irq_handler dmastat:0x%x spistat:0x%x\n",
493 if (drv_data
->rx
!= NULL
) {
494 u16 cr
= bfin_read(&drv_data
->regs
->ctl
);
495 /* discard old RX data and clear RXS */
496 bfin_spi_dummy_read(drv_data
);
497 bfin_write(&drv_data
->regs
->ctl
, cr
& ~BIT_CTL_ENABLE
); /* Disable SPI */
498 bfin_write(&drv_data
->regs
->ctl
, cr
& ~BIT_CTL_TIMOD
); /* Restore State */
499 bfin_write(&drv_data
->regs
->stat
, BIT_STAT_CLR
); /* Clear Status */
502 clear_dma_irqstat(drv_data
->dma_channel
);
505 * wait for the last transaction shifted out. HRM states:
506 * at this point there may still be data in the SPI DMA FIFO waiting
507 * to be transmitted ... software needs to poll TXS in the SPI_STAT
508 * register until it goes low for 2 successive reads
510 if (drv_data
->tx
!= NULL
) {
511 while ((bfin_read(&drv_data
->regs
->stat
) & BIT_STAT_TXS
) ||
512 (bfin_read(&drv_data
->regs
->stat
) & BIT_STAT_TXS
))
516 dev_dbg(&drv_data
->pdev
->dev
,
517 "in dma_irq_handler dmastat:0x%x spistat:0x%x\n",
518 dmastat
, bfin_read(&drv_data
->regs
->stat
));
520 timeout
= jiffies
+ HZ
;
521 while (!(bfin_read(&drv_data
->regs
->stat
) & BIT_STAT_SPIF
))
522 if (!time_before(jiffies
, timeout
)) {
523 dev_warn(&drv_data
->pdev
->dev
, "timeout waiting for SPIF\n");
528 if ((dmastat
& DMA_ERR
) && (spistat
& BIT_STAT_RBSY
)) {
529 msg
->state
= ERROR_STATE
;
530 dev_err(&drv_data
->pdev
->dev
, "dma receive: fifo/buffer overflow\n");
532 msg
->actual_length
+= drv_data
->len_in_bytes
;
534 if (drv_data
->cs_change
)
535 bfin_spi_cs_deactive(drv_data
, chip
);
537 /* Move to next transfer */
538 msg
->state
= bfin_spi_next_transfer(drv_data
);
541 /* Schedule transfer tasklet */
542 tasklet_schedule(&drv_data
->pump_transfers
);
544 /* free the irq handler before next transfer */
545 dev_dbg(&drv_data
->pdev
->dev
,
546 "disable dma channel irq%d\n",
547 drv_data
->dma_channel
);
548 dma_disable_irq_nosync(drv_data
->dma_channel
);
553 static void bfin_spi_pump_transfers(unsigned long data
)
555 struct bfin_spi_master_data
*drv_data
= (struct bfin_spi_master_data
*)data
;
556 struct spi_message
*message
= NULL
;
557 struct spi_transfer
*transfer
= NULL
;
558 struct spi_transfer
*previous
= NULL
;
559 struct bfin_spi_slave_data
*chip
= NULL
;
560 unsigned int bits_per_word
;
561 u16 cr
, cr_width
, dma_width
, dma_config
;
562 u32 tranf_success
= 1;
565 /* Get current state information */
566 message
= drv_data
->cur_msg
;
567 transfer
= drv_data
->cur_transfer
;
568 chip
= drv_data
->cur_chip
;
571 * if msg is error or done, report it back using complete() callback
574 /* Handle for abort */
575 if (message
->state
== ERROR_STATE
) {
576 dev_dbg(&drv_data
->pdev
->dev
, "transfer: we've hit an error\n");
577 message
->status
= -EIO
;
578 bfin_spi_giveback(drv_data
);
582 /* Handle end of message */
583 if (message
->state
== DONE_STATE
) {
584 dev_dbg(&drv_data
->pdev
->dev
, "transfer: all done!\n");
586 bfin_spi_flush(drv_data
);
587 bfin_spi_giveback(drv_data
);
591 /* Delay if requested at end of transfer */
592 if (message
->state
== RUNNING_STATE
) {
593 dev_dbg(&drv_data
->pdev
->dev
, "transfer: still running ...\n");
594 previous
= list_entry(transfer
->transfer_list
.prev
,
595 struct spi_transfer
, transfer_list
);
596 if (previous
->delay_usecs
)
597 udelay(previous
->delay_usecs
);
600 /* Flush any existing transfers that may be sitting in the hardware */
601 if (bfin_spi_flush(drv_data
) == 0) {
602 dev_err(&drv_data
->pdev
->dev
, "pump_transfers: flush failed\n");
603 message
->status
= -EIO
;
604 bfin_spi_giveback(drv_data
);
608 if (transfer
->len
== 0) {
609 /* Move to next transfer of this msg */
610 message
->state
= bfin_spi_next_transfer(drv_data
);
611 /* Schedule next transfer tasklet */
612 tasklet_schedule(&drv_data
->pump_transfers
);
616 if (transfer
->tx_buf
!= NULL
) {
617 drv_data
->tx
= (void *)transfer
->tx_buf
;
618 drv_data
->tx_end
= drv_data
->tx
+ transfer
->len
;
619 dev_dbg(&drv_data
->pdev
->dev
, "tx_buf is %p, tx_end is %p\n",
620 transfer
->tx_buf
, drv_data
->tx_end
);
625 if (transfer
->rx_buf
!= NULL
) {
626 full_duplex
= transfer
->tx_buf
!= NULL
;
627 drv_data
->rx
= transfer
->rx_buf
;
628 drv_data
->rx_end
= drv_data
->rx
+ transfer
->len
;
629 dev_dbg(&drv_data
->pdev
->dev
, "rx_buf is %p, rx_end is %p\n",
630 transfer
->rx_buf
, drv_data
->rx_end
);
635 drv_data
->rx_dma
= transfer
->rx_dma
;
636 drv_data
->tx_dma
= transfer
->tx_dma
;
637 drv_data
->len_in_bytes
= transfer
->len
;
638 drv_data
->cs_change
= transfer
->cs_change
;
640 /* Bits per word setup */
641 bits_per_word
= transfer
->bits_per_word
;
642 if (bits_per_word
== 16) {
643 drv_data
->n_bytes
= bits_per_word
/8;
644 drv_data
->len
= (transfer
->len
) >> 1;
645 cr_width
= BIT_CTL_WORDSIZE
;
646 drv_data
->ops
= &bfin_bfin_spi_transfer_ops_u16
;
647 } else if (bits_per_word
== 8) {
648 drv_data
->n_bytes
= bits_per_word
/8;
649 drv_data
->len
= transfer
->len
;
651 drv_data
->ops
= &bfin_bfin_spi_transfer_ops_u8
;
653 cr
= bfin_read(&drv_data
->regs
->ctl
) & ~(BIT_CTL_TIMOD
| BIT_CTL_WORDSIZE
);
655 bfin_write(&drv_data
->regs
->ctl
, cr
);
657 dev_dbg(&drv_data
->pdev
->dev
,
658 "transfer: drv_data->ops is %p, chip->ops is %p, u8_ops is %p\n",
659 drv_data
->ops
, chip
->ops
, &bfin_bfin_spi_transfer_ops_u8
);
661 message
->state
= RUNNING_STATE
;
664 /* Speed setup (surely valid because already checked) */
665 if (transfer
->speed_hz
)
666 bfin_write(&drv_data
->regs
->baud
, hz_to_spi_baud(transfer
->speed_hz
));
668 bfin_write(&drv_data
->regs
->baud
, chip
->baud
);
670 bfin_write(&drv_data
->regs
->stat
, BIT_STAT_CLR
);
671 bfin_spi_cs_active(drv_data
, chip
);
673 dev_dbg(&drv_data
->pdev
->dev
,
674 "now pumping a transfer: width is %d, len is %d\n",
675 cr_width
, transfer
->len
);
678 * Try to map dma buffer and do a dma transfer. If successful use,
679 * different way to r/w according to the enable_dma settings and if
680 * we are not doing a full duplex transfer (since the hardware does
681 * not support full duplex DMA transfers).
683 if (!full_duplex
&& drv_data
->cur_chip
->enable_dma
684 && drv_data
->len
> 6) {
686 unsigned long dma_start_addr
, flags
;
688 disable_dma(drv_data
->dma_channel
);
689 clear_dma_irqstat(drv_data
->dma_channel
);
691 /* config dma channel */
692 dev_dbg(&drv_data
->pdev
->dev
, "doing dma transfer\n");
693 set_dma_x_count(drv_data
->dma_channel
, drv_data
->len
);
694 if (cr_width
== BIT_CTL_WORDSIZE
) {
695 set_dma_x_modify(drv_data
->dma_channel
, 2);
696 dma_width
= WDSIZE_16
;
698 set_dma_x_modify(drv_data
->dma_channel
, 1);
699 dma_width
= WDSIZE_8
;
702 /* poll for SPI completion before start */
703 while (!(bfin_read(&drv_data
->regs
->stat
) & BIT_STAT_SPIF
))
706 /* dirty hack for autobuffer DMA mode */
707 if (drv_data
->tx_dma
== 0xFFFF) {
708 dev_dbg(&drv_data
->pdev
->dev
,
709 "doing autobuffer DMA out.\n");
711 /* no irq in autobuffer mode */
713 (DMAFLOW_AUTO
| RESTART
| dma_width
| DI_EN
);
714 set_dma_config(drv_data
->dma_channel
, dma_config
);
715 set_dma_start_addr(drv_data
->dma_channel
,
716 (unsigned long)drv_data
->tx
);
717 enable_dma(drv_data
->dma_channel
);
719 /* start SPI transfer */
720 bfin_write(&drv_data
->regs
->ctl
, cr
| BIT_CTL_TIMOD_DMA_TX
);
722 /* just return here, there can only be one transfer
726 bfin_spi_giveback(drv_data
);
730 /* In dma mode, rx or tx must be NULL in one transfer */
731 dma_config
= (RESTART
| dma_width
| DI_EN
);
732 if (drv_data
->rx
!= NULL
) {
733 /* set transfer mode, and enable SPI */
734 dev_dbg(&drv_data
->pdev
->dev
, "doing DMA in to %p (size %zx)\n",
735 drv_data
->rx
, drv_data
->len_in_bytes
);
737 /* invalidate caches, if needed */
738 if (bfin_addr_dcacheable((unsigned long) drv_data
->rx
))
739 invalidate_dcache_range((unsigned long) drv_data
->rx
,
740 (unsigned long) (drv_data
->rx
+
741 drv_data
->len_in_bytes
));
744 dma_start_addr
= (unsigned long)drv_data
->rx
;
745 cr
|= BIT_CTL_TIMOD_DMA_RX
| BIT_CTL_SENDOPT
;
747 } else if (drv_data
->tx
!= NULL
) {
748 dev_dbg(&drv_data
->pdev
->dev
, "doing DMA out.\n");
750 /* flush caches, if needed */
751 if (bfin_addr_dcacheable((unsigned long) drv_data
->tx
))
752 flush_dcache_range((unsigned long) drv_data
->tx
,
753 (unsigned long) (drv_data
->tx
+
754 drv_data
->len_in_bytes
));
756 dma_start_addr
= (unsigned long)drv_data
->tx
;
757 cr
|= BIT_CTL_TIMOD_DMA_TX
;
762 /* oh man, here there be monsters ... and i dont mean the
763 * fluffy cute ones from pixar, i mean the kind that'll eat
764 * your data, kick your dog, and love it all. do *not* try
765 * and change these lines unless you (1) heavily test DMA
766 * with SPI flashes on a loaded system (e.g. ping floods),
767 * (2) know just how broken the DMA engine interaction with
768 * the SPI peripheral is, and (3) have someone else to blame
769 * when you screw it all up anyways.
771 set_dma_start_addr(drv_data
->dma_channel
, dma_start_addr
);
772 set_dma_config(drv_data
->dma_channel
, dma_config
);
773 local_irq_save(flags
);
775 bfin_write(&drv_data
->regs
->ctl
, cr
);
776 enable_dma(drv_data
->dma_channel
);
777 dma_enable_irq(drv_data
->dma_channel
);
778 local_irq_restore(flags
);
784 * We always use SPI_WRITE mode (transfer starts with TDBR write).
785 * SPI_READ mode (transfer starts with RDBR read) seems to have
786 * problems with setting up the output value in TDBR prior to the
787 * start of the transfer.
789 bfin_write(&drv_data
->regs
->ctl
, cr
| BIT_CTL_TXMOD
);
791 if (chip
->pio_interrupt
) {
792 /* SPI irq should have been disabled by now */
794 /* discard old RX data and clear RXS */
795 bfin_spi_dummy_read(drv_data
);
798 if (drv_data
->tx
== NULL
)
799 bfin_write(&drv_data
->regs
->tdbr
, chip
->idle_tx_val
);
802 if (bits_per_word
== 16) {
803 u16
*buf
= (u16
*)drv_data
->tx
;
804 for (loop
= 0; loop
< bits_per_word
/ 16;
806 bfin_write(&drv_data
->regs
->tdbr
, *buf
++);
808 } else if (bits_per_word
== 8) {
809 u8
*buf
= (u8
*)drv_data
->tx
;
810 for (loop
= 0; loop
< bits_per_word
/ 8; loop
++)
811 bfin_write(&drv_data
->regs
->tdbr
, *buf
++);
814 drv_data
->tx
+= drv_data
->n_bytes
;
817 /* once TDBR is empty, interrupt is triggered */
818 enable_irq(drv_data
->spi_irq
);
823 dev_dbg(&drv_data
->pdev
->dev
, "doing IO transfer\n");
826 /* full duplex mode */
827 BUG_ON((drv_data
->tx_end
- drv_data
->tx
) !=
828 (drv_data
->rx_end
- drv_data
->rx
));
829 dev_dbg(&drv_data
->pdev
->dev
,
830 "IO duplex: cr is 0x%x\n", cr
);
832 drv_data
->ops
->duplex(drv_data
);
834 if (drv_data
->tx
!= drv_data
->tx_end
)
836 } else if (drv_data
->tx
!= NULL
) {
837 /* write only half duplex */
838 dev_dbg(&drv_data
->pdev
->dev
,
839 "IO write: cr is 0x%x\n", cr
);
841 drv_data
->ops
->write(drv_data
);
843 if (drv_data
->tx
!= drv_data
->tx_end
)
845 } else if (drv_data
->rx
!= NULL
) {
846 /* read only half duplex */
847 dev_dbg(&drv_data
->pdev
->dev
,
848 "IO read: cr is 0x%x\n", cr
);
850 drv_data
->ops
->read(drv_data
);
851 if (drv_data
->rx
!= drv_data
->rx_end
)
855 if (!tranf_success
) {
856 dev_dbg(&drv_data
->pdev
->dev
,
857 "IO write error!\n");
858 message
->state
= ERROR_STATE
;
860 /* Update total byte transferred */
861 message
->actual_length
+= drv_data
->len_in_bytes
;
862 /* Move to next transfer of this msg */
863 message
->state
= bfin_spi_next_transfer(drv_data
);
864 if (drv_data
->cs_change
&& message
->state
!= DONE_STATE
) {
865 bfin_spi_flush(drv_data
);
866 bfin_spi_cs_deactive(drv_data
, chip
);
870 /* Schedule next transfer tasklet */
871 tasklet_schedule(&drv_data
->pump_transfers
);
874 /* pop a msg from queue and kick off real transfer */
875 static void bfin_spi_pump_messages(struct work_struct
*work
)
877 struct bfin_spi_master_data
*drv_data
;
880 drv_data
= container_of(work
, struct bfin_spi_master_data
, pump_messages
);
882 /* Lock queue and check for queue work */
883 spin_lock_irqsave(&drv_data
->lock
, flags
);
884 if (list_empty(&drv_data
->queue
) || !drv_data
->running
) {
885 /* pumper kicked off but no work to do */
887 spin_unlock_irqrestore(&drv_data
->lock
, flags
);
891 /* Make sure we are not already running a message */
892 if (drv_data
->cur_msg
) {
893 spin_unlock_irqrestore(&drv_data
->lock
, flags
);
897 /* Extract head of queue */
898 drv_data
->cur_msg
= list_entry(drv_data
->queue
.next
,
899 struct spi_message
, queue
);
901 /* Setup the SSP using the per chip configuration */
902 drv_data
->cur_chip
= spi_get_ctldata(drv_data
->cur_msg
->spi
);
903 bfin_spi_restore_state(drv_data
);
905 list_del_init(&drv_data
->cur_msg
->queue
);
907 /* Initial message state */
908 drv_data
->cur_msg
->state
= START_STATE
;
909 drv_data
->cur_transfer
= list_entry(drv_data
->cur_msg
->transfers
.next
,
910 struct spi_transfer
, transfer_list
);
912 dev_dbg(&drv_data
->pdev
->dev
,
913 "got a message to pump, state is set to: baud "
914 "%d, flag 0x%x, ctl 0x%x\n",
915 drv_data
->cur_chip
->baud
, drv_data
->cur_chip
->flag
,
916 drv_data
->cur_chip
->ctl_reg
);
918 dev_dbg(&drv_data
->pdev
->dev
,
919 "the first transfer len is %d\n",
920 drv_data
->cur_transfer
->len
);
922 /* Mark as busy and launch transfers */
923 tasklet_schedule(&drv_data
->pump_transfers
);
926 spin_unlock_irqrestore(&drv_data
->lock
, flags
);
930 * got a msg to transfer, queue it in drv_data->queue.
931 * And kick off message pumper
933 static int bfin_spi_transfer(struct spi_device
*spi
, struct spi_message
*msg
)
935 struct bfin_spi_master_data
*drv_data
= spi_master_get_devdata(spi
->master
);
938 spin_lock_irqsave(&drv_data
->lock
, flags
);
940 if (!drv_data
->running
) {
941 spin_unlock_irqrestore(&drv_data
->lock
, flags
);
945 msg
->actual_length
= 0;
946 msg
->status
= -EINPROGRESS
;
947 msg
->state
= START_STATE
;
949 dev_dbg(&spi
->dev
, "adding an msg in transfer() \n");
950 list_add_tail(&msg
->queue
, &drv_data
->queue
);
952 if (drv_data
->running
&& !drv_data
->busy
)
953 queue_work(drv_data
->workqueue
, &drv_data
->pump_messages
);
955 spin_unlock_irqrestore(&drv_data
->lock
, flags
);
960 #define MAX_SPI_SSEL 7
962 static const u16 ssel
[][MAX_SPI_SSEL
] = {
963 {P_SPI0_SSEL1
, P_SPI0_SSEL2
, P_SPI0_SSEL3
,
964 P_SPI0_SSEL4
, P_SPI0_SSEL5
,
965 P_SPI0_SSEL6
, P_SPI0_SSEL7
},
967 {P_SPI1_SSEL1
, P_SPI1_SSEL2
, P_SPI1_SSEL3
,
968 P_SPI1_SSEL4
, P_SPI1_SSEL5
,
969 P_SPI1_SSEL6
, P_SPI1_SSEL7
},
971 {P_SPI2_SSEL1
, P_SPI2_SSEL2
, P_SPI2_SSEL3
,
972 P_SPI2_SSEL4
, P_SPI2_SSEL5
,
973 P_SPI2_SSEL6
, P_SPI2_SSEL7
},
976 /* setup for devices (may be called multiple times -- not just first setup) */
977 static int bfin_spi_setup(struct spi_device
*spi
)
979 struct bfin5xx_spi_chip
*chip_info
;
980 struct bfin_spi_slave_data
*chip
= NULL
;
981 struct bfin_spi_master_data
*drv_data
= spi_master_get_devdata(spi
->master
);
985 /* Only alloc (or use chip_info) on first setup */
987 chip
= spi_get_ctldata(spi
);
989 chip
= kzalloc(sizeof(*chip
), GFP_KERNEL
);
991 dev_err(&spi
->dev
, "cannot allocate chip data\n");
996 chip
->enable_dma
= 0;
997 chip_info
= spi
->controller_data
;
1000 /* Let people set non-standard bits directly */
1001 bfin_ctl_reg
= BIT_CTL_OPENDRAIN
| BIT_CTL_EMISO
|
1002 BIT_CTL_PSSE
| BIT_CTL_GM
| BIT_CTL_SZ
;
1004 /* chip_info isn't always needed */
1006 /* Make sure people stop trying to set fields via ctl_reg
1007 * when they should actually be using common SPI framework.
1008 * Currently we let through: WOM EMISO PSSE GM SZ.
1009 * Not sure if a user actually needs/uses any of these,
1010 * but let's assume (for now) they do.
1012 if (chip_info
->ctl_reg
& ~bfin_ctl_reg
) {
1014 "do not set bits in ctl_reg that the SPI framework manages\n");
1017 chip
->enable_dma
= chip_info
->enable_dma
!= 0
1018 && drv_data
->master_info
->enable_dma
;
1019 chip
->ctl_reg
= chip_info
->ctl_reg
;
1020 chip
->cs_chg_udelay
= chip_info
->cs_chg_udelay
;
1021 chip
->idle_tx_val
= chip_info
->idle_tx_val
;
1022 chip
->pio_interrupt
= chip_info
->pio_interrupt
;
1024 /* force a default base state */
1025 chip
->ctl_reg
&= bfin_ctl_reg
;
1028 /* translate common spi framework into our register */
1029 if (spi
->mode
& SPI_CPOL
)
1030 chip
->ctl_reg
|= BIT_CTL_CPOL
;
1031 if (spi
->mode
& SPI_CPHA
)
1032 chip
->ctl_reg
|= BIT_CTL_CPHA
;
1033 if (spi
->mode
& SPI_LSB_FIRST
)
1034 chip
->ctl_reg
|= BIT_CTL_LSBF
;
1035 /* we dont support running in slave mode (yet?) */
1036 chip
->ctl_reg
|= BIT_CTL_MASTER
;
1039 * Notice: for blackfin, the speed_hz is the value of register
1040 * SPI_BAUD, not the real baudrate
1042 chip
->baud
= hz_to_spi_baud(spi
->max_speed_hz
);
1043 chip
->chip_select_num
= spi
->chip_select
;
1044 if (chip
->chip_select_num
< MAX_CTRL_CS
) {
1045 if (!(spi
->mode
& SPI_CPHA
))
1047 "Warning: SPI CPHA not set: Slave Select not under software control!\n"
1048 "See Documentation/blackfin/bfin-spi-notes.txt\n");
1050 chip
->flag
= (1 << spi
->chip_select
) << 8;
1052 chip
->cs_gpio
= chip
->chip_select_num
- MAX_CTRL_CS
;
1054 if (chip
->enable_dma
&& chip
->pio_interrupt
) {
1056 "enable_dma is set, do not set pio_interrupt\n");
1060 * if any one SPI chip is registered and wants DMA, request the
1061 * DMA channel for it
1063 if (chip
->enable_dma
&& !drv_data
->dma_requested
) {
1064 /* register dma irq handler */
1065 ret
= request_dma(drv_data
->dma_channel
, "BFIN_SPI_DMA");
1068 "Unable to request BlackFin SPI DMA channel\n");
1071 drv_data
->dma_requested
= 1;
1073 ret
= set_dma_callback(drv_data
->dma_channel
,
1074 bfin_spi_dma_irq_handler
, drv_data
);
1076 dev_err(&spi
->dev
, "Unable to set dma callback\n");
1079 dma_disable_irq(drv_data
->dma_channel
);
1082 if (chip
->pio_interrupt
&& !drv_data
->irq_requested
) {
1083 ret
= request_irq(drv_data
->spi_irq
, bfin_spi_pio_irq_handler
,
1084 0, "BFIN_SPI", drv_data
);
1086 dev_err(&spi
->dev
, "Unable to register spi IRQ\n");
1089 drv_data
->irq_requested
= 1;
1090 /* we use write mode, spi irq has to be disabled here */
1091 disable_irq(drv_data
->spi_irq
);
1094 if (chip
->chip_select_num
>= MAX_CTRL_CS
) {
1095 /* Only request on first setup */
1096 if (spi_get_ctldata(spi
) == NULL
) {
1097 ret
= gpio_request(chip
->cs_gpio
, spi
->modalias
);
1099 dev_err(&spi
->dev
, "gpio_request() error\n");
1102 gpio_direction_output(chip
->cs_gpio
, 1);
1106 dev_dbg(&spi
->dev
, "setup spi chip %s, width is %d, dma is %d\n",
1107 spi
->modalias
, spi
->bits_per_word
, chip
->enable_dma
);
1108 dev_dbg(&spi
->dev
, "ctl_reg is 0x%x, flag_reg is 0x%x\n",
1109 chip
->ctl_reg
, chip
->flag
);
1111 spi_set_ctldata(spi
, chip
);
1113 dev_dbg(&spi
->dev
, "chip select number is %d\n", chip
->chip_select_num
);
1114 if (chip
->chip_select_num
< MAX_CTRL_CS
) {
1115 ret
= peripheral_request(ssel
[spi
->master
->bus_num
]
1116 [chip
->chip_select_num
-1], spi
->modalias
);
1118 dev_err(&spi
->dev
, "peripheral_request() error\n");
1123 bfin_spi_cs_enable(drv_data
, chip
);
1124 bfin_spi_cs_deactive(drv_data
, chip
);
1129 if (chip
->chip_select_num
>= MAX_CTRL_CS
)
1130 gpio_free(chip
->cs_gpio
);
1132 peripheral_free(ssel
[spi
->master
->bus_num
]
1133 [chip
->chip_select_num
- 1]);
1136 if (drv_data
->dma_requested
)
1137 free_dma(drv_data
->dma_channel
);
1138 drv_data
->dma_requested
= 0;
1141 /* prevent free 'chip' twice */
1142 spi_set_ctldata(spi
, NULL
);
1149 * callback for spi framework.
1150 * clean driver specific data
1152 static void bfin_spi_cleanup(struct spi_device
*spi
)
1154 struct bfin_spi_slave_data
*chip
= spi_get_ctldata(spi
);
1155 struct bfin_spi_master_data
*drv_data
= spi_master_get_devdata(spi
->master
);
1160 if (chip
->chip_select_num
< MAX_CTRL_CS
) {
1161 peripheral_free(ssel
[spi
->master
->bus_num
]
1162 [chip
->chip_select_num
-1]);
1163 bfin_spi_cs_disable(drv_data
, chip
);
1165 gpio_free(chip
->cs_gpio
);
1168 /* prevent free 'chip' twice */
1169 spi_set_ctldata(spi
, NULL
);
1172 static int bfin_spi_init_queue(struct bfin_spi_master_data
*drv_data
)
1174 INIT_LIST_HEAD(&drv_data
->queue
);
1175 spin_lock_init(&drv_data
->lock
);
1177 drv_data
->running
= false;
1180 /* init transfer tasklet */
1181 tasklet_init(&drv_data
->pump_transfers
,
1182 bfin_spi_pump_transfers
, (unsigned long)drv_data
);
1184 /* init messages workqueue */
1185 INIT_WORK(&drv_data
->pump_messages
, bfin_spi_pump_messages
);
1186 drv_data
->workqueue
= create_singlethread_workqueue(
1187 dev_name(drv_data
->master
->dev
.parent
));
1188 if (drv_data
->workqueue
== NULL
)
1194 static int bfin_spi_start_queue(struct bfin_spi_master_data
*drv_data
)
1196 unsigned long flags
;
1198 spin_lock_irqsave(&drv_data
->lock
, flags
);
1200 if (drv_data
->running
|| drv_data
->busy
) {
1201 spin_unlock_irqrestore(&drv_data
->lock
, flags
);
1205 drv_data
->running
= true;
1206 drv_data
->cur_msg
= NULL
;
1207 drv_data
->cur_transfer
= NULL
;
1208 drv_data
->cur_chip
= NULL
;
1209 spin_unlock_irqrestore(&drv_data
->lock
, flags
);
1211 queue_work(drv_data
->workqueue
, &drv_data
->pump_messages
);
1216 static int bfin_spi_stop_queue(struct bfin_spi_master_data
*drv_data
)
1218 unsigned long flags
;
1219 unsigned limit
= 500;
1222 spin_lock_irqsave(&drv_data
->lock
, flags
);
1225 * This is a bit lame, but is optimized for the common execution path.
1226 * A wait_queue on the drv_data->busy could be used, but then the common
1227 * execution path (pump_messages) would be required to call wake_up or
1228 * friends on every SPI message. Do this instead
1230 drv_data
->running
= false;
1231 while ((!list_empty(&drv_data
->queue
) || drv_data
->busy
) && limit
--) {
1232 spin_unlock_irqrestore(&drv_data
->lock
, flags
);
1234 spin_lock_irqsave(&drv_data
->lock
, flags
);
1237 if (!list_empty(&drv_data
->queue
) || drv_data
->busy
)
1240 spin_unlock_irqrestore(&drv_data
->lock
, flags
);
1245 static int bfin_spi_destroy_queue(struct bfin_spi_master_data
*drv_data
)
1249 status
= bfin_spi_stop_queue(drv_data
);
1253 destroy_workqueue(drv_data
->workqueue
);
1258 static int bfin_spi_probe(struct platform_device
*pdev
)
1260 struct device
*dev
= &pdev
->dev
;
1261 struct bfin5xx_spi_master
*platform_info
;
1262 struct spi_master
*master
;
1263 struct bfin_spi_master_data
*drv_data
;
1264 struct resource
*res
;
1267 platform_info
= dev_get_platdata(dev
);
1269 /* Allocate master with space for drv_data */
1270 master
= spi_alloc_master(dev
, sizeof(*drv_data
));
1272 dev_err(&pdev
->dev
, "can not alloc spi_master\n");
1276 drv_data
= spi_master_get_devdata(master
);
1277 drv_data
->master
= master
;
1278 drv_data
->master_info
= platform_info
;
1279 drv_data
->pdev
= pdev
;
1280 drv_data
->pin_req
= platform_info
->pin_req
;
1282 /* the spi->mode bits supported by this driver: */
1283 master
->mode_bits
= SPI_CPOL
| SPI_CPHA
| SPI_LSB_FIRST
;
1284 master
->bits_per_word_mask
= SPI_BPW_MASK(8) | SPI_BPW_MASK(16);
1285 master
->bus_num
= pdev
->id
;
1286 master
->num_chipselect
= platform_info
->num_chipselect
;
1287 master
->cleanup
= bfin_spi_cleanup
;
1288 master
->setup
= bfin_spi_setup
;
1289 master
->transfer
= bfin_spi_transfer
;
1291 /* Find and map our resources */
1292 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
1294 dev_err(dev
, "Cannot get IORESOURCE_MEM\n");
1296 goto out_error_get_res
;
1299 drv_data
->regs
= ioremap(res
->start
, resource_size(res
));
1300 if (drv_data
->regs
== NULL
) {
1301 dev_err(dev
, "Cannot map IO\n");
1303 goto out_error_ioremap
;
1306 res
= platform_get_resource(pdev
, IORESOURCE_DMA
, 0);
1308 dev_err(dev
, "No DMA channel specified\n");
1310 goto out_error_free_io
;
1312 drv_data
->dma_channel
= res
->start
;
1314 drv_data
->spi_irq
= platform_get_irq(pdev
, 0);
1315 if (drv_data
->spi_irq
< 0) {
1316 dev_err(dev
, "No spi pio irq specified\n");
1318 goto out_error_free_io
;
1321 /* Initial and start queue */
1322 status
= bfin_spi_init_queue(drv_data
);
1324 dev_err(dev
, "problem initializing queue\n");
1325 goto out_error_queue_alloc
;
1328 status
= bfin_spi_start_queue(drv_data
);
1330 dev_err(dev
, "problem starting queue\n");
1331 goto out_error_queue_alloc
;
1334 status
= peripheral_request_list(drv_data
->pin_req
, DRV_NAME
);
1336 dev_err(&pdev
->dev
, ": Requesting Peripherals failed\n");
1337 goto out_error_queue_alloc
;
1340 /* Reset SPI registers. If these registers were used by the boot loader,
1341 * the sky may fall on your head if you enable the dma controller.
1343 bfin_write(&drv_data
->regs
->ctl
, BIT_CTL_CPHA
| BIT_CTL_MASTER
);
1344 bfin_write(&drv_data
->regs
->flg
, 0xFF00);
1346 /* Register with the SPI framework */
1347 platform_set_drvdata(pdev
, drv_data
);
1348 status
= spi_register_master(master
);
1350 dev_err(dev
, "problem registering spi master\n");
1351 goto out_error_queue_alloc
;
1354 dev_info(dev
, "%s, Version %s, regs@%p, dma channel@%d\n",
1355 DRV_DESC
, DRV_VERSION
, drv_data
->regs
,
1356 drv_data
->dma_channel
);
1359 out_error_queue_alloc
:
1360 bfin_spi_destroy_queue(drv_data
);
1362 iounmap(drv_data
->regs
);
1365 spi_master_put(master
);
1370 /* stop hardware and remove the driver */
1371 static int bfin_spi_remove(struct platform_device
*pdev
)
1373 struct bfin_spi_master_data
*drv_data
= platform_get_drvdata(pdev
);
1379 /* Remove the queue */
1380 status
= bfin_spi_destroy_queue(drv_data
);
1384 /* Disable the SSP at the peripheral and SOC level */
1385 bfin_spi_disable(drv_data
);
1388 if (drv_data
->master_info
->enable_dma
) {
1389 if (dma_channel_active(drv_data
->dma_channel
))
1390 free_dma(drv_data
->dma_channel
);
1393 if (drv_data
->irq_requested
) {
1394 free_irq(drv_data
->spi_irq
, drv_data
);
1395 drv_data
->irq_requested
= 0;
1398 /* Disconnect from the SPI framework */
1399 spi_unregister_master(drv_data
->master
);
1401 peripheral_free_list(drv_data
->pin_req
);
1406 #ifdef CONFIG_PM_SLEEP
1407 static int bfin_spi_suspend(struct device
*dev
)
1409 struct bfin_spi_master_data
*drv_data
= dev_get_drvdata(dev
);
1412 status
= bfin_spi_stop_queue(drv_data
);
1416 drv_data
->ctrl_reg
= bfin_read(&drv_data
->regs
->ctl
);
1417 drv_data
->flag_reg
= bfin_read(&drv_data
->regs
->flg
);
1420 * reset SPI_CTL and SPI_FLG registers
1422 bfin_write(&drv_data
->regs
->ctl
, BIT_CTL_CPHA
| BIT_CTL_MASTER
);
1423 bfin_write(&drv_data
->regs
->flg
, 0xFF00);
1428 static int bfin_spi_resume(struct device
*dev
)
1430 struct bfin_spi_master_data
*drv_data
= dev_get_drvdata(dev
);
1433 bfin_write(&drv_data
->regs
->ctl
, drv_data
->ctrl_reg
);
1434 bfin_write(&drv_data
->regs
->flg
, drv_data
->flag_reg
);
1436 /* Start the queue running */
1437 status
= bfin_spi_start_queue(drv_data
);
1439 dev_err(dev
, "problem starting queue (%d)\n", status
);
1446 static SIMPLE_DEV_PM_OPS(bfin_spi_pm_ops
, bfin_spi_suspend
, bfin_spi_resume
);
1448 #define BFIN_SPI_PM_OPS (&bfin_spi_pm_ops)
1450 #define BFIN_SPI_PM_OPS NULL
1453 MODULE_ALIAS("platform:bfin-spi");
1454 static struct platform_driver bfin_spi_driver
= {
1457 .owner
= THIS_MODULE
,
1458 .pm
= BFIN_SPI_PM_OPS
,
1460 .probe
= bfin_spi_probe
,
1461 .remove
= bfin_spi_remove
,
1464 static int __init
bfin_spi_init(void)
1466 return platform_driver_register(&bfin_spi_driver
);
1468 subsys_initcall(bfin_spi_init
);
1470 static void __exit
bfin_spi_exit(void)
1472 platform_driver_unregister(&bfin_spi_driver
);
1474 module_exit(bfin_spi_exit
);