Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
[pandora-kernel.git] / drivers / spi / spi_bfin5xx.c
1 /*
2  * File:         drivers/spi/bfin5xx_spi.c
3  * Based on:     N/A
4  * Author:       Luke Yang (Analog Devices Inc.)
5  *
6  * Created:      March. 10th 2006
7  * Description:  SPI controller driver for Blackfin 5xx
8  * Bugs:         Enter bugs at http://blackfin.uclinux.org/
9  *
10  * Modified:
11  *      March 10, 2006  bfin5xx_spi.c Created. (Luke Yang)
12  *      August 7, 2006  added full duplex mode (Axel Weiss & Luke Yang)
13  *
14  * Copyright 2004-2006 Analog Devices Inc.
15  *
16  * This program is free software ;  you can redistribute it and/or modify
17  * it under the terms of the GNU General Public License as published by
18  * the Free Software Foundation ;  either version 2, or (at your option)
19  * any later version.
20  *
21  * This program is distributed in the hope that it will be useful,
22  * but WITHOUT ANY WARRANTY ;  without even the implied warranty of
23  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
24  * GNU General Public License for more details.
25  *
26  * You should have received a copy of the GNU General Public License
27  * along with this program ;  see the file COPYING.
28  * If not, write to the Free Software Foundation,
29  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
30  */
31
32 #include <linux/init.h>
33 #include <linux/module.h>
34 #include <linux/device.h>
35 #include <linux/ioport.h>
36 #include <linux/errno.h>
37 #include <linux/interrupt.h>
38 #include <linux/platform_device.h>
39 #include <linux/dma-mapping.h>
40 #include <linux/spi/spi.h>
41 #include <linux/workqueue.h>
42 #include <linux/errno.h>
43 #include <linux/delay.h>
44
45 #include <asm/io.h>
46 #include <asm/irq.h>
47 #include <asm/delay.h>
48 #include <asm/dma.h>
49
50 #include <asm/bfin5xx_spi.h>
51
52 MODULE_AUTHOR("Luke Yang");
53 MODULE_DESCRIPTION("Blackfin 5xx SPI Contoller");
54 MODULE_LICENSE("GPL");
55
56 #define IS_DMA_ALIGNED(x) (((u32)(x)&0x07)==0)
57
58 #define DEFINE_SPI_REG(reg, off) \
59 static inline u16 read_##reg(void) \
60             { return *(volatile unsigned short*)(SPI0_REGBASE + off); } \
61 static inline void write_##reg(u16 v) \
62             {*(volatile unsigned short*)(SPI0_REGBASE + off) = v;\
63              SSYNC();}
64
65 DEFINE_SPI_REG(CTRL, 0x00)
66 DEFINE_SPI_REG(FLAG, 0x04)
67 DEFINE_SPI_REG(STAT, 0x08)
68 DEFINE_SPI_REG(TDBR, 0x0C)
69 DEFINE_SPI_REG(RDBR, 0x10)
70 DEFINE_SPI_REG(BAUD, 0x14)
71 DEFINE_SPI_REG(SHAW, 0x18)
72 #define START_STATE ((void*)0)
73 #define RUNNING_STATE ((void*)1)
74 #define DONE_STATE ((void*)2)
75 #define ERROR_STATE ((void*)-1)
76 #define QUEUE_RUNNING 0
77 #define QUEUE_STOPPED 1
78 int dma_requested;
79
80 struct driver_data {
81         /* Driver model hookup */
82         struct platform_device *pdev;
83
84         /* SPI framework hookup */
85         struct spi_master *master;
86
87         /* BFIN hookup */
88         struct bfin5xx_spi_master *master_info;
89
90         /* Driver message queue */
91         struct workqueue_struct *workqueue;
92         struct work_struct pump_messages;
93         spinlock_t lock;
94         struct list_head queue;
95         int busy;
96         int run;
97
98         /* Message Transfer pump */
99         struct tasklet_struct pump_transfers;
100
101         /* Current message transfer state info */
102         struct spi_message *cur_msg;
103         struct spi_transfer *cur_transfer;
104         struct chip_data *cur_chip;
105         size_t len_in_bytes;
106         size_t len;
107         void *tx;
108         void *tx_end;
109         void *rx;
110         void *rx_end;
111         int dma_mapped;
112         dma_addr_t rx_dma;
113         dma_addr_t tx_dma;
114         size_t rx_map_len;
115         size_t tx_map_len;
116         u8 n_bytes;
117         void (*write) (struct driver_data *);
118         void (*read) (struct driver_data *);
119         void (*duplex) (struct driver_data *);
120 };
121
122 struct chip_data {
123         u16 ctl_reg;
124         u16 baud;
125         u16 flag;
126
127         u8 chip_select_num;
128         u8 n_bytes;
129         u8 width;               /* 0 or 1 */
130         u8 enable_dma;
131         u8 bits_per_word;       /* 8 or 16 */
132         u8 cs_change_per_word;
133         u8 cs_chg_udelay;
134         void (*write) (struct driver_data *);
135         void (*read) (struct driver_data *);
136         void (*duplex) (struct driver_data *);
137 };
138
139 static void bfin_spi_enable(struct driver_data *drv_data)
140 {
141         u16 cr;
142
143         cr = read_CTRL();
144         write_CTRL(cr | BIT_CTL_ENABLE);
145         SSYNC();
146 }
147
148 static void bfin_spi_disable(struct driver_data *drv_data)
149 {
150         u16 cr;
151
152         cr = read_CTRL();
153         write_CTRL(cr & (~BIT_CTL_ENABLE));
154         SSYNC();
155 }
156
157 /* Caculate the SPI_BAUD register value based on input HZ */
158 static u16 hz_to_spi_baud(u32 speed_hz)
159 {
160         u_long sclk = get_sclk();
161         u16 spi_baud = (sclk / (2 * speed_hz));
162
163         if ((sclk % (2 * speed_hz)) > 0)
164                 spi_baud++;
165
166         return spi_baud;
167 }
168
169 static int flush(struct driver_data *drv_data)
170 {
171         unsigned long limit = loops_per_jiffy << 1;
172
173         /* wait for stop and clear stat */
174         while (!(read_STAT() & BIT_STAT_SPIF) && limit--)
175                 continue;
176
177         write_STAT(BIT_STAT_CLR);
178
179         return limit;
180 }
181
182 /* stop controller and re-config current chip*/
183 static void restore_state(struct driver_data *drv_data)
184 {
185         struct chip_data *chip = drv_data->cur_chip;
186
187         /* Clear status and disable clock */
188         write_STAT(BIT_STAT_CLR);
189         bfin_spi_disable(drv_data);
190         dev_dbg(&drv_data->pdev->dev, "restoring spi ctl state\n");
191
192 #if defined(CONFIG_BF534) || defined(CONFIG_BF536) || defined(CONFIG_BF537)
193         dev_dbg(&drv_data->pdev->dev, 
194                 "chip select number is %d\n", chip->chip_select_num);
195         
196         switch (chip->chip_select_num) {
197         case 1:
198                 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3c00);
199                 SSYNC();
200                 break;
201
202         case 2:
203         case 3:
204                 bfin_write_PORT_MUX(bfin_read_PORT_MUX() | PJSE_SPI);
205                 SSYNC();
206                 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3800);
207                 SSYNC();
208                 break;
209
210         case 4:
211                 bfin_write_PORT_MUX(bfin_read_PORT_MUX() | PFS4E_SPI);
212                 SSYNC();
213                 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3840);
214                 SSYNC();
215                 break;
216
217         case 5:
218                 bfin_write_PORT_MUX(bfin_read_PORT_MUX() | PFS5E_SPI);
219                 SSYNC();
220                 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3820);
221                 SSYNC();
222                 break;
223
224         case 6:
225                 bfin_write_PORT_MUX(bfin_read_PORT_MUX() | PFS6E_SPI);
226                 SSYNC();
227                 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3810);
228                 SSYNC();
229                 break;
230
231         case 7:
232                 bfin_write_PORT_MUX(bfin_read_PORT_MUX() | PJCE_SPI);
233                 SSYNC();
234                 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3800);
235                 SSYNC();
236                 break;
237         }
238 #endif
239
240         /* Load the registers */
241         write_CTRL(chip->ctl_reg);
242         write_BAUD(chip->baud);
243         write_FLAG(chip->flag);
244 }
245
246 /* used to kick off transfer in rx mode */
247 static unsigned short dummy_read(void)
248 {
249         unsigned short tmp;
250         tmp = read_RDBR();
251         return tmp;
252 }
253
254 static void null_writer(struct driver_data *drv_data)
255 {
256         u8 n_bytes = drv_data->n_bytes;
257
258         while (drv_data->tx < drv_data->tx_end) {
259                 write_TDBR(0);
260                 while ((read_STAT() & BIT_STAT_TXS))
261                         continue;
262                 drv_data->tx += n_bytes;
263         }
264 }
265
266 static void null_reader(struct driver_data *drv_data)
267 {
268         u8 n_bytes = drv_data->n_bytes;
269         dummy_read();
270
271         while (drv_data->rx < drv_data->rx_end) {
272                 while (!(read_STAT() & BIT_STAT_RXS))
273                         continue;
274                 dummy_read();
275                 drv_data->rx += n_bytes;
276         }
277 }
278
279 static void u8_writer(struct driver_data *drv_data)
280 {
281         dev_dbg(&drv_data->pdev->dev, 
282                 "cr8-s is 0x%x\n", read_STAT());
283         while (drv_data->tx < drv_data->tx_end) {
284                 write_TDBR(*(u8 *) (drv_data->tx));
285                 while (read_STAT() & BIT_STAT_TXS)
286                         continue;
287                 ++drv_data->tx;
288         }
289
290         /* poll for SPI completion before returning */
291         while (!(read_STAT() & BIT_STAT_SPIF))
292                 continue;
293 }
294
295 static void u8_cs_chg_writer(struct driver_data *drv_data)
296 {
297         struct chip_data *chip = drv_data->cur_chip;
298
299         while (drv_data->tx < drv_data->tx_end) {
300                 write_FLAG(chip->flag);
301                 SSYNC();
302
303                 write_TDBR(*(u8 *) (drv_data->tx));
304                 while (read_STAT() & BIT_STAT_TXS)
305                         continue;
306                 while (!(read_STAT() & BIT_STAT_SPIF))
307                         continue;
308                 write_FLAG(0xFF00 | chip->flag);
309                 SSYNC();
310                 if (chip->cs_chg_udelay)
311                         udelay(chip->cs_chg_udelay);
312                 ++drv_data->tx;
313         }
314         write_FLAG(0xFF00);
315         SSYNC();
316 }
317
318 static void u8_reader(struct driver_data *drv_data)
319 {
320         dev_dbg(&drv_data->pdev->dev, 
321                 "cr-8 is 0x%x\n", read_STAT());
322
323         /* clear TDBR buffer before read(else it will be shifted out) */
324         write_TDBR(0xFFFF);
325
326         dummy_read();
327
328         while (drv_data->rx < drv_data->rx_end - 1) {
329                 while (!(read_STAT() & BIT_STAT_RXS))
330                         continue;
331                 *(u8 *) (drv_data->rx) = read_RDBR();
332                 ++drv_data->rx;
333         }
334
335         while (!(read_STAT() & BIT_STAT_RXS))
336                 continue;
337         *(u8 *) (drv_data->rx) = read_SHAW();
338         ++drv_data->rx;
339 }
340
341 static void u8_cs_chg_reader(struct driver_data *drv_data)
342 {
343         struct chip_data *chip = drv_data->cur_chip;
344
345         while (drv_data->rx < drv_data->rx_end) {
346                 write_FLAG(chip->flag);
347                 SSYNC();
348
349                 read_RDBR();    /* kick off */
350                 while (!(read_STAT() & BIT_STAT_RXS))
351                         continue;
352                 while (!(read_STAT() & BIT_STAT_SPIF))
353                         continue;
354                 *(u8 *) (drv_data->rx) = read_SHAW();
355                 write_FLAG(0xFF00 | chip->flag);
356                 SSYNC();
357                 if (chip->cs_chg_udelay)
358                         udelay(chip->cs_chg_udelay);
359                 ++drv_data->rx;
360         }
361         write_FLAG(0xFF00);
362         SSYNC();
363 }
364
365 static void u8_duplex(struct driver_data *drv_data)
366 {
367         /* in duplex mode, clk is triggered by writing of TDBR */
368         while (drv_data->rx < drv_data->rx_end) {
369                 write_TDBR(*(u8 *) (drv_data->tx));
370                 while (!(read_STAT() & BIT_STAT_SPIF))
371                         continue;
372                 while (!(read_STAT() & BIT_STAT_RXS))
373                         continue;
374                 *(u8 *) (drv_data->rx) = read_RDBR();
375                 ++drv_data->rx;
376                 ++drv_data->tx;
377         }
378 }
379
380 static void u8_cs_chg_duplex(struct driver_data *drv_data)
381 {
382         struct chip_data *chip = drv_data->cur_chip;
383
384         while (drv_data->rx < drv_data->rx_end) {
385                 write_FLAG(chip->flag);
386                 SSYNC();
387
388                 write_TDBR(*(u8 *) (drv_data->tx));
389                 while (!(read_STAT() & BIT_STAT_SPIF))
390                         continue;
391                 while (!(read_STAT() & BIT_STAT_RXS))
392                         continue;
393                 *(u8 *) (drv_data->rx) = read_RDBR();
394                 write_FLAG(0xFF00 | chip->flag);
395                 SSYNC();
396                 if (chip->cs_chg_udelay)
397                         udelay(chip->cs_chg_udelay);
398                 ++drv_data->rx;
399                 ++drv_data->tx;
400         }
401         write_FLAG(0xFF00);
402         SSYNC();
403 }
404
405 static void u16_writer(struct driver_data *drv_data)
406 {
407         dev_dbg(&drv_data->pdev->dev, 
408                 "cr16 is 0x%x\n", read_STAT());
409
410         while (drv_data->tx < drv_data->tx_end) {
411                 write_TDBR(*(u16 *) (drv_data->tx));
412                 while ((read_STAT() & BIT_STAT_TXS))
413                         continue;
414                 drv_data->tx += 2;
415         }
416
417         /* poll for SPI completion before returning */
418         while (!(read_STAT() & BIT_STAT_SPIF))
419                 continue;
420 }
421
422 static void u16_cs_chg_writer(struct driver_data *drv_data)
423 {
424         struct chip_data *chip = drv_data->cur_chip;
425
426         while (drv_data->tx < drv_data->tx_end) {
427                 write_FLAG(chip->flag);
428                 SSYNC();
429
430                 write_TDBR(*(u16 *) (drv_data->tx));
431                 while ((read_STAT() & BIT_STAT_TXS))
432                         continue;
433                 while (!(read_STAT() & BIT_STAT_SPIF))
434                         continue;
435                 write_FLAG(0xFF00 | chip->flag);
436                 SSYNC();
437                 if (chip->cs_chg_udelay)
438                         udelay(chip->cs_chg_udelay);
439                 drv_data->tx += 2;
440         }
441         write_FLAG(0xFF00);
442         SSYNC();
443 }
444
445 static void u16_reader(struct driver_data *drv_data)
446 {
447         dev_dbg(&drv_data->pdev->dev,
448                 "cr-16 is 0x%x\n", read_STAT());
449         dummy_read();
450
451         while (drv_data->rx < (drv_data->rx_end - 2)) {
452                 while (!(read_STAT() & BIT_STAT_RXS))
453                         continue;
454                 *(u16 *) (drv_data->rx) = read_RDBR();
455                 drv_data->rx += 2;
456         }
457
458         while (!(read_STAT() & BIT_STAT_RXS))
459                 continue;
460         *(u16 *) (drv_data->rx) = read_SHAW();
461         drv_data->rx += 2;
462 }
463
464 static void u16_cs_chg_reader(struct driver_data *drv_data)
465 {
466         struct chip_data *chip = drv_data->cur_chip;
467
468         while (drv_data->rx < drv_data->rx_end) {
469                 write_FLAG(chip->flag);
470                 SSYNC();
471
472                 read_RDBR();    /* kick off */
473                 while (!(read_STAT() & BIT_STAT_RXS))
474                         continue;
475                 while (!(read_STAT() & BIT_STAT_SPIF))
476                         continue;
477                 *(u16 *) (drv_data->rx) = read_SHAW();
478                 write_FLAG(0xFF00 | chip->flag);
479                 SSYNC();
480                 if (chip->cs_chg_udelay)
481                         udelay(chip->cs_chg_udelay);
482                 drv_data->rx += 2;
483         }
484         write_FLAG(0xFF00);
485         SSYNC();
486 }
487
488 static void u16_duplex(struct driver_data *drv_data)
489 {
490         /* in duplex mode, clk is triggered by writing of TDBR */
491         while (drv_data->tx < drv_data->tx_end) {
492                 write_TDBR(*(u16 *) (drv_data->tx));
493                 while (!(read_STAT() & BIT_STAT_SPIF))
494                         continue;
495                 while (!(read_STAT() & BIT_STAT_RXS))
496                         continue;
497                 *(u16 *) (drv_data->rx) = read_RDBR();
498                 drv_data->rx += 2;
499                 drv_data->tx += 2;
500         }
501 }
502
503 static void u16_cs_chg_duplex(struct driver_data *drv_data)
504 {
505         struct chip_data *chip = drv_data->cur_chip;
506
507         while (drv_data->tx < drv_data->tx_end) {
508                 write_FLAG(chip->flag);
509                 SSYNC();
510
511                 write_TDBR(*(u16 *) (drv_data->tx));
512                 while (!(read_STAT() & BIT_STAT_SPIF))
513                         continue;
514                 while (!(read_STAT() & BIT_STAT_RXS))
515                         continue;
516                 *(u16 *) (drv_data->rx) = read_RDBR();
517                 write_FLAG(0xFF00 | chip->flag);
518                 SSYNC();
519                 if (chip->cs_chg_udelay)
520                         udelay(chip->cs_chg_udelay);
521                 drv_data->rx += 2;
522                 drv_data->tx += 2;
523         }
524         write_FLAG(0xFF00);
525         SSYNC();
526 }
527
528 /* test if ther is more transfer to be done */
529 static void *next_transfer(struct driver_data *drv_data)
530 {
531         struct spi_message *msg = drv_data->cur_msg;
532         struct spi_transfer *trans = drv_data->cur_transfer;
533
534         /* Move to next transfer */
535         if (trans->transfer_list.next != &msg->transfers) {
536                 drv_data->cur_transfer =
537                     list_entry(trans->transfer_list.next,
538                                struct spi_transfer, transfer_list);
539                 return RUNNING_STATE;
540         } else
541                 return DONE_STATE;
542 }
543
544 /*
545  * caller already set message->status;
546  * dma and pio irqs are blocked give finished message back
547  */
548 static void giveback(struct driver_data *drv_data)
549 {
550         struct spi_transfer *last_transfer;
551         unsigned long flags;
552         struct spi_message *msg;
553
554         spin_lock_irqsave(&drv_data->lock, flags);
555         msg = drv_data->cur_msg;
556         drv_data->cur_msg = NULL;
557         drv_data->cur_transfer = NULL;
558         drv_data->cur_chip = NULL;
559         queue_work(drv_data->workqueue, &drv_data->pump_messages);
560         spin_unlock_irqrestore(&drv_data->lock, flags);
561
562         last_transfer = list_entry(msg->transfers.prev,
563                                    struct spi_transfer, transfer_list);
564
565         msg->state = NULL;
566
567         /* disable chip select signal. And not stop spi in autobuffer mode */
568         if (drv_data->tx_dma != 0xFFFF) {
569                 write_FLAG(0xFF00);
570                 bfin_spi_disable(drv_data);
571         }
572
573         if (msg->complete)
574                 msg->complete(msg->context);
575 }
576
577 static irqreturn_t dma_irq_handler(int irq, void *dev_id)
578 {
579         struct driver_data *drv_data = (struct driver_data *)dev_id;
580         struct spi_message *msg = drv_data->cur_msg;
581
582         dev_dbg(&drv_data->pdev->dev, "in dma_irq_handler\n");
583         clear_dma_irqstat(CH_SPI);
584
585         /*
586          * wait for the last transaction shifted out.  yes, these two
587          * while loops are supposed to be the same (see the HRM).
588          */
589         if (drv_data->tx != NULL) {
590                 while (bfin_read_SPI_STAT() & TXS)
591                         continue;
592                 while (bfin_read_SPI_STAT() & TXS)
593                         continue;
594         }
595
596         while (!(bfin_read_SPI_STAT() & SPIF))
597                 continue;
598
599         bfin_spi_disable(drv_data);
600
601         msg->actual_length += drv_data->len_in_bytes;
602
603         /* Move to next transfer */
604         msg->state = next_transfer(drv_data);
605
606         /* Schedule transfer tasklet */
607         tasklet_schedule(&drv_data->pump_transfers);
608
609         /* free the irq handler before next transfer */
610         dev_dbg(&drv_data->pdev->dev,
611                 "disable dma channel irq%d\n",
612                 CH_SPI);
613         dma_disable_irq(CH_SPI);
614
615         return IRQ_HANDLED;
616 }
617
618 static void pump_transfers(unsigned long data)
619 {
620         struct driver_data *drv_data = (struct driver_data *)data;
621         struct spi_message *message = NULL;
622         struct spi_transfer *transfer = NULL;
623         struct spi_transfer *previous = NULL;
624         struct chip_data *chip = NULL;
625         u8 width;
626         u16 cr, dma_width, dma_config;
627         u32 tranf_success = 1;
628
629         /* Get current state information */
630         message = drv_data->cur_msg;
631         transfer = drv_data->cur_transfer;
632         chip = drv_data->cur_chip;
633
634         /*
635          * if msg is error or done, report it back using complete() callback
636          */
637
638          /* Handle for abort */
639         if (message->state == ERROR_STATE) {
640                 message->status = -EIO;
641                 giveback(drv_data);
642                 return;
643         }
644
645         /* Handle end of message */
646         if (message->state == DONE_STATE) {
647                 message->status = 0;
648                 giveback(drv_data);
649                 return;
650         }
651
652         /* Delay if requested at end of transfer */
653         if (message->state == RUNNING_STATE) {
654                 previous = list_entry(transfer->transfer_list.prev,
655                                       struct spi_transfer, transfer_list);
656                 if (previous->delay_usecs)
657                         udelay(previous->delay_usecs);
658         }
659
660         /* Setup the transfer state based on the type of transfer */
661         if (flush(drv_data) == 0) {
662                 dev_err(&drv_data->pdev->dev, "pump_transfers: flush failed\n");
663                 message->status = -EIO;
664                 giveback(drv_data);
665                 return;
666         }
667
668         if (transfer->tx_buf != NULL) {
669                 drv_data->tx = (void *)transfer->tx_buf;
670                 drv_data->tx_end = drv_data->tx + transfer->len;
671                 dev_dbg(&drv_data->pdev->dev, "tx_buf is %p, tx_end is %p\n",
672                         transfer->tx_buf, drv_data->tx_end);
673         } else {
674                 drv_data->tx = NULL;
675         }
676
677         if (transfer->rx_buf != NULL) {
678                 drv_data->rx = transfer->rx_buf;
679                 drv_data->rx_end = drv_data->rx + transfer->len;
680                 dev_dbg(&drv_data->pdev->dev, "rx_buf is %p, rx_end is %p\n",
681                         transfer->rx_buf, drv_data->rx_end);
682         } else {
683                 drv_data->rx = NULL;
684         }
685
686         drv_data->rx_dma = transfer->rx_dma;
687         drv_data->tx_dma = transfer->tx_dma;
688         drv_data->len_in_bytes = transfer->len;
689
690         width = chip->width;
691         if (width == CFG_SPI_WORDSIZE16) {
692                 drv_data->len = (transfer->len) >> 1;
693         } else {
694                 drv_data->len = transfer->len;
695         }
696         drv_data->write = drv_data->tx ? chip->write : null_writer;
697         drv_data->read = drv_data->rx ? chip->read : null_reader;
698         drv_data->duplex = chip->duplex ? chip->duplex : null_writer;
699         dev_dbg(&drv_data->pdev->dev,
700                 "transfer: drv_data->write is %p, chip->write is %p, null_wr is %p\n",
701                 drv_data->write, chip->write, null_writer);
702
703         /* speed and width has been set on per message */
704         message->state = RUNNING_STATE;
705         dma_config = 0;
706
707         /* restore spi status for each spi transfer */
708         if (transfer->speed_hz) {
709                 write_BAUD(hz_to_spi_baud(transfer->speed_hz));
710         } else {
711                 write_BAUD(chip->baud);
712         }
713         write_FLAG(chip->flag);
714
715         dev_dbg(&drv_data->pdev->dev,
716                 "now pumping a transfer: width is %d, len is %d\n",
717                 width, transfer->len);
718
719         /*
720          * Try to map dma buffer and do a dma transfer if
721          * successful use different way to r/w according to
722          * drv_data->cur_chip->enable_dma
723          */
724         if (drv_data->cur_chip->enable_dma && drv_data->len > 6) {
725
726                 write_STAT(BIT_STAT_CLR);
727                 disable_dma(CH_SPI);
728                 clear_dma_irqstat(CH_SPI);
729                 bfin_spi_disable(drv_data);
730
731                 /* config dma channel */
732                 dev_dbg(&drv_data->pdev->dev, "doing dma transfer\n");
733                 if (width == CFG_SPI_WORDSIZE16) {
734                         set_dma_x_count(CH_SPI, drv_data->len);
735                         set_dma_x_modify(CH_SPI, 2);
736                         dma_width = WDSIZE_16;
737                 } else {
738                         set_dma_x_count(CH_SPI, drv_data->len);
739                         set_dma_x_modify(CH_SPI, 1);
740                         dma_width = WDSIZE_8;
741                 }
742
743                 /* set transfer width,direction. And enable spi */
744                 cr = (read_CTRL() & (~BIT_CTL_TIMOD));
745
746                 /* dirty hack for autobuffer DMA mode */
747                 if (drv_data->tx_dma == 0xFFFF) {
748                         dev_dbg(&drv_data->pdev->dev,
749                                 "doing autobuffer DMA out.\n");
750
751                         /* no irq in autobuffer mode */
752                         dma_config =
753                             (DMAFLOW_AUTO | RESTART | dma_width | DI_EN);
754                         set_dma_config(CH_SPI, dma_config);
755                         set_dma_start_addr(CH_SPI, (unsigned long)drv_data->tx);
756                         enable_dma(CH_SPI);
757                         write_CTRL(cr | CFG_SPI_DMAWRITE | (width << 8) |
758                                    (CFG_SPI_ENABLE << 14));
759
760                         /* just return here, there can only be one transfer in this mode */
761                         message->status = 0;
762                         giveback(drv_data);
763                         return;
764                 }
765
766                 /* In dma mode, rx or tx must be NULL in one transfer */
767                 if (drv_data->rx != NULL) {
768                         /* set transfer mode, and enable SPI */
769                         dev_dbg(&drv_data->pdev->dev, "doing DMA in.\n");
770
771                         /* disable SPI before write to TDBR */
772                         write_CTRL(cr & ~BIT_CTL_ENABLE);
773
774                         /* clear tx reg soformer data is not shifted out */
775                         write_TDBR(0xFF);
776
777                         set_dma_x_count(CH_SPI, drv_data->len);
778
779                         /* start dma */
780                         dma_enable_irq(CH_SPI);
781                         dma_config = (WNR | RESTART | dma_width | DI_EN);
782                         set_dma_config(CH_SPI, dma_config);
783                         set_dma_start_addr(CH_SPI, (unsigned long)drv_data->rx);
784                         enable_dma(CH_SPI);
785
786                         cr |=
787                             CFG_SPI_DMAREAD | (width << 8) | (CFG_SPI_ENABLE <<
788                                                               14);
789                         /* set transfer mode, and enable SPI */
790                         write_CTRL(cr);
791                 } else if (drv_data->tx != NULL) {
792                         dev_dbg(&drv_data->pdev->dev, "doing DMA out.\n");
793
794                         /* start dma */
795                         dma_enable_irq(CH_SPI);
796                         dma_config = (RESTART | dma_width | DI_EN);
797                         set_dma_config(CH_SPI, dma_config);
798                         set_dma_start_addr(CH_SPI, (unsigned long)drv_data->tx);
799                         enable_dma(CH_SPI);
800
801                         write_CTRL(cr | CFG_SPI_DMAWRITE | (width << 8) |
802                                    (CFG_SPI_ENABLE << 14));
803
804                 }
805         } else {
806                 /* IO mode write then read */
807                 dev_dbg(&drv_data->pdev->dev, "doing IO transfer\n");
808
809                 write_STAT(BIT_STAT_CLR);
810
811                 if (drv_data->tx != NULL && drv_data->rx != NULL) {
812                         /* full duplex mode */
813                         BUG_ON((drv_data->tx_end - drv_data->tx) !=
814                                (drv_data->rx_end - drv_data->rx));
815                         cr = (read_CTRL() & (~BIT_CTL_TIMOD));  
816                         cr |= CFG_SPI_WRITE | (width << 8) |
817                                 (CFG_SPI_ENABLE << 14);
818                         dev_dbg(&drv_data->pdev->dev,
819                                 "IO duplex: cr is 0x%x\n", cr);
820
821                         write_CTRL(cr);
822                         SSYNC();
823
824                         drv_data->duplex(drv_data);
825
826                         if (drv_data->tx != drv_data->tx_end)
827                                 tranf_success = 0;
828                 } else if (drv_data->tx != NULL) {
829                         /* write only half duplex */
830                         cr = (read_CTRL() & (~BIT_CTL_TIMOD));
831                         cr |= CFG_SPI_WRITE | (width << 8) |
832                                 (CFG_SPI_ENABLE << 14);
833                         dev_dbg(&drv_data->pdev->dev, 
834                                 "IO write: cr is 0x%x\n", cr);
835
836                         write_CTRL(cr);
837                         SSYNC();
838
839                         drv_data->write(drv_data);
840
841                         if (drv_data->tx != drv_data->tx_end)
842                                 tranf_success = 0;
843                 } else if (drv_data->rx != NULL) {
844                         /* read only half duplex */
845                         cr = (read_CTRL() & (~BIT_CTL_TIMOD));
846                         cr |= CFG_SPI_READ | (width << 8) |
847                                 (CFG_SPI_ENABLE << 14);
848                         dev_dbg(&drv_data->pdev->dev, 
849                                 "IO read: cr is 0x%x\n", cr);
850
851                         write_CTRL(cr);
852                         SSYNC();
853
854                         drv_data->read(drv_data);
855                         if (drv_data->rx != drv_data->rx_end)
856                                 tranf_success = 0;
857                 }
858
859                 if (!tranf_success) {
860                         dev_dbg(&drv_data->pdev->dev, 
861                                 "IO write error!\n");
862                         message->state = ERROR_STATE;
863                 } else {
864                         /* Update total byte transfered */
865                         message->actual_length += drv_data->len;
866
867                         /* Move to next transfer of this msg */
868                         message->state = next_transfer(drv_data);
869                 }
870
871                 /* Schedule next transfer tasklet */
872                 tasklet_schedule(&drv_data->pump_transfers);
873
874         }
875 }
876
877 /* pop a msg from queue and kick off real transfer */
878 static void pump_messages(struct work_struct *work)
879 {
880         struct driver_data *drv_data = container_of(work, struct driver_data, pump_messages);
881         unsigned long flags;
882
883         /* Lock queue and check for queue work */
884         spin_lock_irqsave(&drv_data->lock, flags);
885         if (list_empty(&drv_data->queue) || drv_data->run == QUEUE_STOPPED) {
886                 /* pumper kicked off but no work to do */
887                 drv_data->busy = 0;
888                 spin_unlock_irqrestore(&drv_data->lock, flags);
889                 return;
890         }
891
892         /* Make sure we are not already running a message */
893         if (drv_data->cur_msg) {
894                 spin_unlock_irqrestore(&drv_data->lock, flags);
895                 return;
896         }
897
898         /* Extract head of queue */
899         drv_data->cur_msg = list_entry(drv_data->queue.next,
900                                        struct spi_message, queue);
901         list_del_init(&drv_data->cur_msg->queue);
902
903         /* Initial message state */
904         drv_data->cur_msg->state = START_STATE;
905         drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next,
906                                             struct spi_transfer, transfer_list);
907
908         /* Setup the SSP using the per chip configuration */
909         drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi);
910         restore_state(drv_data);
911         dev_dbg(&drv_data->pdev->dev,
912                 "got a message to pump, state is set to: baud %d, flag 0x%x, ctl 0x%x\n",
913                 drv_data->cur_chip->baud, drv_data->cur_chip->flag,
914                 drv_data->cur_chip->ctl_reg);
915         
916         dev_dbg(&drv_data->pdev->dev, 
917                 "the first transfer len is %d\n",
918                 drv_data->cur_transfer->len);
919
920         /* Mark as busy and launch transfers */
921         tasklet_schedule(&drv_data->pump_transfers);
922
923         drv_data->busy = 1;
924         spin_unlock_irqrestore(&drv_data->lock, flags);
925 }
926
927 /*
928  * got a msg to transfer, queue it in drv_data->queue.
929  * And kick off message pumper
930  */
931 static int transfer(struct spi_device *spi, struct spi_message *msg)
932 {
933         struct driver_data *drv_data = spi_master_get_devdata(spi->master);
934         unsigned long flags;
935
936         spin_lock_irqsave(&drv_data->lock, flags);
937
938         if (drv_data->run == QUEUE_STOPPED) {
939                 spin_unlock_irqrestore(&drv_data->lock, flags);
940                 return -ESHUTDOWN;
941         }
942
943         msg->actual_length = 0;
944         msg->status = -EINPROGRESS;
945         msg->state = START_STATE;
946
947         dev_dbg(&spi->dev, "adding an msg in transfer() \n");
948         list_add_tail(&msg->queue, &drv_data->queue);
949
950         if (drv_data->run == QUEUE_RUNNING && !drv_data->busy)
951                 queue_work(drv_data->workqueue, &drv_data->pump_messages);
952
953         spin_unlock_irqrestore(&drv_data->lock, flags);
954
955         return 0;
956 }
957
958 /* first setup for new devices */
959 static int setup(struct spi_device *spi)
960 {
961         struct bfin5xx_spi_chip *chip_info = NULL;
962         struct chip_data *chip;
963         struct driver_data *drv_data = spi_master_get_devdata(spi->master);
964         u8 spi_flg;
965
966         /* Abort device setup if requested features are not supported */
967         if (spi->mode & ~(SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST)) {
968                 dev_err(&spi->dev, "requested mode not fully supported\n");
969                 return -EINVAL;
970         }
971
972         /* Zero (the default) here means 8 bits */
973         if (!spi->bits_per_word)
974                 spi->bits_per_word = 8;
975
976         if (spi->bits_per_word != 8 && spi->bits_per_word != 16)
977                 return -EINVAL;
978
979         /* Only alloc (or use chip_info) on first setup */
980         chip = spi_get_ctldata(spi);
981         if (chip == NULL) {
982                 chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
983                 if (!chip)
984                         return -ENOMEM;
985
986                 chip->enable_dma = 0;
987                 chip_info = spi->controller_data;
988         }
989
990         /* chip_info isn't always needed */
991         if (chip_info) {
992                 chip->enable_dma = chip_info->enable_dma != 0
993                     && drv_data->master_info->enable_dma;
994                 chip->ctl_reg = chip_info->ctl_reg;
995                 chip->bits_per_word = chip_info->bits_per_word;
996                 chip->cs_change_per_word = chip_info->cs_change_per_word;
997                 chip->cs_chg_udelay = chip_info->cs_chg_udelay;
998         }
999
1000         /* translate common spi framework into our register */
1001         if (spi->mode & SPI_CPOL)
1002                 chip->ctl_reg |= CPOL;
1003         if (spi->mode & SPI_CPHA)
1004                 chip->ctl_reg |= CPHA;
1005         if (spi->mode & SPI_LSB_FIRST)
1006                 chip->ctl_reg |= LSBF;
1007         /* we dont support running in slave mode (yet?) */
1008         chip->ctl_reg |= MSTR;
1009
1010         /*
1011          * if any one SPI chip is registered and wants DMA, request the
1012          * DMA channel for it
1013          */
1014         if (chip->enable_dma && !dma_requested) {
1015                 /* register dma irq handler */
1016                 if (request_dma(CH_SPI, "BF53x_SPI_DMA") < 0) {
1017                         dev_dbg(&spi->dev,
1018                                 "Unable to request BlackFin SPI DMA channel\n");
1019                         return -ENODEV;
1020                 }
1021                 if (set_dma_callback(CH_SPI, (void *)dma_irq_handler, drv_data)
1022                     < 0) {
1023                         dev_dbg(&spi->dev, "Unable to set dma callback\n");
1024                         return -EPERM;
1025                 }
1026                 dma_disable_irq(CH_SPI);
1027                 dma_requested = 1;
1028         }
1029
1030         /*
1031          * Notice: for blackfin, the speed_hz is the value of register
1032          * SPI_BAUD, not the real baudrate
1033          */
1034         chip->baud = hz_to_spi_baud(spi->max_speed_hz);
1035         spi_flg = ~(1 << (spi->chip_select));
1036         chip->flag = ((u16) spi_flg << 8) | (1 << (spi->chip_select));
1037         chip->chip_select_num = spi->chip_select;
1038
1039         switch (chip->bits_per_word) {
1040         case 8:
1041                 chip->n_bytes = 1;
1042                 chip->width = CFG_SPI_WORDSIZE8;
1043                 chip->read = chip->cs_change_per_word ?
1044                         u8_cs_chg_reader : u8_reader;
1045                 chip->write = chip->cs_change_per_word ?
1046                         u8_cs_chg_writer : u8_writer;
1047                 chip->duplex = chip->cs_change_per_word ?
1048                         u8_cs_chg_duplex : u8_duplex;
1049                 break;
1050
1051         case 16:
1052                 chip->n_bytes = 2;
1053                 chip->width = CFG_SPI_WORDSIZE16;
1054                 chip->read = chip->cs_change_per_word ?
1055                         u16_cs_chg_reader : u16_reader;
1056                 chip->write = chip->cs_change_per_word ?
1057                         u16_cs_chg_writer : u16_writer;
1058                 chip->duplex = chip->cs_change_per_word ?
1059                         u16_cs_chg_duplex : u16_duplex;
1060                 break;
1061
1062         default:
1063                 dev_err(&spi->dev, "%d bits_per_word is not supported\n",
1064                                 chip->bits_per_word);
1065                 kfree(chip);
1066                 return -ENODEV;
1067         }
1068
1069         dev_dbg(&spi->dev, "setup spi chip %s, width is %d, dma is %d,",
1070                         spi->modalias, chip->width, chip->enable_dma);
1071         dev_dbg(&spi->dev, "ctl_reg is 0x%x, flag_reg is 0x%x\n",
1072                         chip->ctl_reg, chip->flag);
1073
1074         spi_set_ctldata(spi, chip);
1075
1076         return 0;
1077 }
1078
1079 /*
1080  * callback for spi framework.
1081  * clean driver specific data
1082  */
1083 static void cleanup(struct spi_device *spi)
1084 {
1085         struct chip_data *chip = spi_get_ctldata((struct spi_device *)spi);
1086
1087         kfree(chip);
1088 }
1089
1090 static inline int init_queue(struct driver_data *drv_data)
1091 {
1092         INIT_LIST_HEAD(&drv_data->queue);
1093         spin_lock_init(&drv_data->lock);
1094
1095         drv_data->run = QUEUE_STOPPED;
1096         drv_data->busy = 0;
1097
1098         /* init transfer tasklet */
1099         tasklet_init(&drv_data->pump_transfers,
1100                      pump_transfers, (unsigned long)drv_data);
1101
1102         /* init messages workqueue */
1103         INIT_WORK(&drv_data->pump_messages, pump_messages);
1104         drv_data->workqueue =
1105             create_singlethread_workqueue(drv_data->master->cdev.dev->bus_id);
1106         if (drv_data->workqueue == NULL)
1107                 return -EBUSY;
1108
1109         return 0;
1110 }
1111
1112 static inline int start_queue(struct driver_data *drv_data)
1113 {
1114         unsigned long flags;
1115
1116         spin_lock_irqsave(&drv_data->lock, flags);
1117
1118         if (drv_data->run == QUEUE_RUNNING || drv_data->busy) {
1119                 spin_unlock_irqrestore(&drv_data->lock, flags);
1120                 return -EBUSY;
1121         }
1122
1123         drv_data->run = QUEUE_RUNNING;
1124         drv_data->cur_msg = NULL;
1125         drv_data->cur_transfer = NULL;
1126         drv_data->cur_chip = NULL;
1127         spin_unlock_irqrestore(&drv_data->lock, flags);
1128
1129         queue_work(drv_data->workqueue, &drv_data->pump_messages);
1130
1131         return 0;
1132 }
1133
1134 static inline int stop_queue(struct driver_data *drv_data)
1135 {
1136         unsigned long flags;
1137         unsigned limit = 500;
1138         int status = 0;
1139
1140         spin_lock_irqsave(&drv_data->lock, flags);
1141
1142         /*
1143          * This is a bit lame, but is optimized for the common execution path.
1144          * A wait_queue on the drv_data->busy could be used, but then the common
1145          * execution path (pump_messages) would be required to call wake_up or
1146          * friends on every SPI message. Do this instead
1147          */
1148         drv_data->run = QUEUE_STOPPED;
1149         while (!list_empty(&drv_data->queue) && drv_data->busy && limit--) {
1150                 spin_unlock_irqrestore(&drv_data->lock, flags);
1151                 msleep(10);
1152                 spin_lock_irqsave(&drv_data->lock, flags);
1153         }
1154
1155         if (!list_empty(&drv_data->queue) || drv_data->busy)
1156                 status = -EBUSY;
1157
1158         spin_unlock_irqrestore(&drv_data->lock, flags);
1159
1160         return status;
1161 }
1162
1163 static inline int destroy_queue(struct driver_data *drv_data)
1164 {
1165         int status;
1166
1167         status = stop_queue(drv_data);
1168         if (status != 0)
1169                 return status;
1170
1171         destroy_workqueue(drv_data->workqueue);
1172
1173         return 0;
1174 }
1175
1176 static int __init bfin5xx_spi_probe(struct platform_device *pdev)
1177 {
1178         struct device *dev = &pdev->dev;
1179         struct bfin5xx_spi_master *platform_info;
1180         struct spi_master *master;
1181         struct driver_data *drv_data = 0;
1182         int status = 0;
1183
1184         platform_info = dev->platform_data;
1185
1186         /* Allocate master with space for drv_data */
1187         master = spi_alloc_master(dev, sizeof(struct driver_data) + 16);
1188         if (!master) {
1189                 dev_err(&pdev->dev, "can not alloc spi_master\n");
1190                 return -ENOMEM;
1191         }
1192         drv_data = spi_master_get_devdata(master);
1193         drv_data->master = master;
1194         drv_data->master_info = platform_info;
1195         drv_data->pdev = pdev;
1196
1197         master->bus_num = pdev->id;
1198         master->num_chipselect = platform_info->num_chipselect;
1199         master->cleanup = cleanup;
1200         master->setup = setup;
1201         master->transfer = transfer;
1202
1203         /* Initial and start queue */
1204         status = init_queue(drv_data);
1205         if (status != 0) {
1206                 dev_err(&pdev->dev, "problem initializing queue\n");
1207                 goto out_error_queue_alloc;
1208         }
1209         status = start_queue(drv_data);
1210         if (status != 0) {
1211                 dev_err(&pdev->dev, "problem starting queue\n");
1212                 goto out_error_queue_alloc;
1213         }
1214
1215         /* Register with the SPI framework */
1216         platform_set_drvdata(pdev, drv_data);
1217         status = spi_register_master(master);
1218         if (status != 0) {
1219                 dev_err(&pdev->dev, "problem registering spi master\n");
1220                 goto out_error_queue_alloc;
1221         }
1222         dev_dbg(&pdev->dev, "controller probe successfully\n");
1223         return status;
1224
1225       out_error_queue_alloc:
1226         destroy_queue(drv_data);
1227         spi_master_put(master);
1228         return status;
1229 }
1230
1231 /* stop hardware and remove the driver */
1232 static int __devexit bfin5xx_spi_remove(struct platform_device *pdev)
1233 {
1234         struct driver_data *drv_data = platform_get_drvdata(pdev);
1235         int status = 0;
1236
1237         if (!drv_data)
1238                 return 0;
1239
1240         /* Remove the queue */
1241         status = destroy_queue(drv_data);
1242         if (status != 0)
1243                 return status;
1244
1245         /* Disable the SSP at the peripheral and SOC level */
1246         bfin_spi_disable(drv_data);
1247
1248         /* Release DMA */
1249         if (drv_data->master_info->enable_dma) {
1250                 if (dma_channel_active(CH_SPI))
1251                         free_dma(CH_SPI);
1252         }
1253
1254         /* Disconnect from the SPI framework */
1255         spi_unregister_master(drv_data->master);
1256
1257         /* Prevent double remove */
1258         platform_set_drvdata(pdev, NULL);
1259
1260         return 0;
1261 }
1262
1263 #ifdef CONFIG_PM
1264 static int bfin5xx_spi_suspend(struct platform_device *pdev, pm_message_t state)
1265 {
1266         struct driver_data *drv_data = platform_get_drvdata(pdev);
1267         int status = 0;
1268
1269         status = stop_queue(drv_data);
1270         if (status != 0)
1271                 return status;
1272
1273         /* stop hardware */
1274         bfin_spi_disable(drv_data);
1275
1276         return 0;
1277 }
1278
1279 static int bfin5xx_spi_resume(struct platform_device *pdev)
1280 {
1281         struct driver_data *drv_data = platform_get_drvdata(pdev);
1282         int status = 0;
1283
1284         /* Enable the SPI interface */
1285         bfin_spi_enable(drv_data);
1286
1287         /* Start the queue running */
1288         status = start_queue(drv_data);
1289         if (status != 0) {
1290                 dev_err(&pdev->dev, "problem starting queue (%d)\n", status);
1291                 return status;
1292         }
1293
1294         return 0;
1295 }
1296 #else
1297 #define bfin5xx_spi_suspend NULL
1298 #define bfin5xx_spi_resume NULL
1299 #endif                          /* CONFIG_PM */
1300
1301 static struct platform_driver bfin5xx_spi_driver = {
1302         .driver         = {
1303                 .name   = "bfin-spi-master",
1304                 .owner  = THIS_MODULE,
1305         },
1306         .suspend        = bfin5xx_spi_suspend,
1307         .resume         = bfin5xx_spi_resume,
1308         .remove         = __devexit_p(bfin5xx_spi_remove),
1309 };
1310
1311 static int __init bfin5xx_spi_init(void)
1312 {
1313         return platform_driver_probe(&bfin5xx_spi_driver, bfin5xx_spi_probe);
1314 }
1315 module_init(bfin5xx_spi_init);
1316
1317 static void __exit bfin5xx_spi_exit(void)
1318 {
1319         platform_driver_unregister(&bfin5xx_spi_driver);
1320 }
1321 module_exit(bfin5xx_spi_exit);