2 * File: drivers/spi/bfin5xx_spi.c
4 * Author: Luke Yang (Analog Devices Inc.)
6 * Created: March. 10th 2006
7 * Description: SPI controller driver for Blackfin 5xx
8 * Bugs: Enter bugs at http://blackfin.uclinux.org/
11 * March 10, 2006 bfin5xx_spi.c Created. (Luke Yang)
12 * August 7, 2006 added full duplex mode (Axel Weiss & Luke Yang)
14 * Copyright 2004-2006 Analog Devices Inc.
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)
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.
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.
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>
47 #include <asm/delay.h>
50 #include <asm/bfin5xx_spi.h>
52 MODULE_AUTHOR("Luke Yang");
53 MODULE_DESCRIPTION("Blackfin 5xx SPI Contoller");
54 MODULE_LICENSE("GPL");
56 #define IS_DMA_ALIGNED(x) (((u32)(x)&0x07)==0)
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;\
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
81 /* Driver model hookup */
82 struct platform_device *pdev;
84 /* SPI framework hookup */
85 struct spi_master *master;
88 struct bfin5xx_spi_master *master_info;
90 /* Driver message queue */
91 struct workqueue_struct *workqueue;
92 struct work_struct pump_messages;
94 struct list_head queue;
98 /* Message Transfer pump */
99 struct tasklet_struct pump_transfers;
101 /* Current message transfer state info */
102 struct spi_message *cur_msg;
103 struct spi_transfer *cur_transfer;
104 struct chip_data *cur_chip;
117 void (*write) (struct driver_data *);
118 void (*read) (struct driver_data *);
119 void (*duplex) (struct driver_data *);
129 u32 width; /* 0 or 1 */
131 u8 bits_per_word; /* 8 or 16 */
132 u8 cs_change_per_word;
134 void (*write) (struct driver_data *);
135 void (*read) (struct driver_data *);
136 void (*duplex) (struct driver_data *);
139 void bfin_spi_enable(struct driver_data *drv_data)
144 write_CTRL(cr | BIT_CTL_ENABLE);
148 void bfin_spi_disable(struct driver_data *drv_data)
153 write_CTRL(cr & (~BIT_CTL_ENABLE));
157 /* Caculate the SPI_BAUD register value based on input HZ */
158 static u16 hz_to_spi_baud(u32 speed_hz)
160 u_long sclk = get_sclk();
161 u16 spi_baud = (sclk / (2 * speed_hz));
163 if ((sclk % (2 * speed_hz)) > 0)
166 pr_debug("sclk = %ld, speed_hz = %d, spi_baud = %d\n", sclk, speed_hz,
172 static int flush(struct driver_data *drv_data)
174 unsigned long limit = loops_per_jiffy << 1;
176 /* wait for stop and clear stat */
177 while (!(read_STAT() & BIT_STAT_SPIF) && limit--)
180 write_STAT(BIT_STAT_CLR);
185 /* stop controller and re-config current chip*/
186 static void restore_state(struct driver_data *drv_data)
188 struct chip_data *chip = drv_data->cur_chip;
190 /* Clear status and disable clock */
191 write_STAT(BIT_STAT_CLR);
192 bfin_spi_disable(drv_data);
193 pr_debug("restoring spi ctl state\n");
195 #if defined(CONFIG_BF534) || defined(CONFIG_BF536) || defined(CONFIG_BF537)
196 pr_debug("chip select number is %d\n", chip->chip_select_num);
198 switch (chip->chip_select_num) {
200 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3c00);
206 bfin_write_PORT_MUX(bfin_read_PORT_MUX() | PJSE_SPI);
208 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3800);
213 bfin_write_PORT_MUX(bfin_read_PORT_MUX() | PFS4E_SPI);
215 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3840);
220 bfin_write_PORT_MUX(bfin_read_PORT_MUX() | PFS5E_SPI);
222 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3820);
227 bfin_write_PORT_MUX(bfin_read_PORT_MUX() | PFS6E_SPI);
229 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3810);
234 bfin_write_PORT_MUX(bfin_read_PORT_MUX() | PJCE_SPI);
236 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3800);
242 /* Load the registers */
243 write_CTRL(chip->ctl_reg);
244 write_BAUD(chip->baud);
245 write_FLAG(chip->flag);
248 /* used to kick off transfer in rx mode */
249 static unsigned short dummy_read(void)
256 static void null_writer(struct driver_data *drv_data)
258 u8 n_bytes = drv_data->n_bytes;
260 while (drv_data->tx < drv_data->tx_end) {
262 while ((read_STAT() & BIT_STAT_TXS))
264 drv_data->tx += n_bytes;
268 static void null_reader(struct driver_data *drv_data)
270 u8 n_bytes = drv_data->n_bytes;
273 while (drv_data->rx < drv_data->rx_end) {
274 while (!(read_STAT() & BIT_STAT_RXS))
277 drv_data->rx += n_bytes;
281 static void u8_writer(struct driver_data *drv_data)
283 pr_debug("cr8-s is 0x%x\n", read_STAT());
284 while (drv_data->tx < drv_data->tx_end) {
285 write_TDBR(*(u8 *) (drv_data->tx));
286 while (read_STAT() & BIT_STAT_TXS)
291 /* poll for SPI completion before returning */
292 while (!(read_STAT() & BIT_STAT_SPIF))
296 static void u8_cs_chg_writer(struct driver_data *drv_data)
298 struct chip_data *chip = drv_data->cur_chip;
300 while (drv_data->tx < drv_data->tx_end) {
301 write_FLAG(chip->flag);
304 write_TDBR(*(u8 *) (drv_data->tx));
305 while (read_STAT() & BIT_STAT_TXS)
307 while (!(read_STAT() & BIT_STAT_SPIF))
309 write_FLAG(0xFF00 | chip->flag);
311 if (chip->cs_chg_udelay)
312 udelay(chip->cs_chg_udelay);
319 static void u8_reader(struct driver_data *drv_data)
321 pr_debug("cr-8 is 0x%x\n", read_STAT());
323 /* clear TDBR buffer before read(else it will be shifted out) */
328 while (drv_data->rx < drv_data->rx_end - 1) {
329 while (!(read_STAT() & BIT_STAT_RXS))
331 *(u8 *) (drv_data->rx) = read_RDBR();
335 while (!(read_STAT() & BIT_STAT_RXS))
337 *(u8 *) (drv_data->rx) = read_SHAW();
341 static void u8_cs_chg_reader(struct driver_data *drv_data)
343 struct chip_data *chip = drv_data->cur_chip;
345 while (drv_data->rx < drv_data->rx_end) {
346 write_FLAG(chip->flag);
349 read_RDBR(); /* kick off */
350 while (!(read_STAT() & BIT_STAT_RXS))
352 while (!(read_STAT() & BIT_STAT_SPIF))
354 *(u8 *) (drv_data->rx) = read_SHAW();
355 write_FLAG(0xFF00 | chip->flag);
357 if (chip->cs_chg_udelay)
358 udelay(chip->cs_chg_udelay);
365 static void u8_duplex(struct driver_data *drv_data)
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))
372 while (!(read_STAT() & BIT_STAT_RXS))
374 *(u8 *) (drv_data->rx) = read_RDBR();
380 static void u8_cs_chg_duplex(struct driver_data *drv_data)
382 struct chip_data *chip = drv_data->cur_chip;
384 while (drv_data->rx < drv_data->rx_end) {
385 write_FLAG(chip->flag);
388 write_TDBR(*(u8 *) (drv_data->tx));
389 while (!(read_STAT() & BIT_STAT_SPIF))
391 while (!(read_STAT() & BIT_STAT_RXS))
393 *(u8 *) (drv_data->rx) = read_RDBR();
394 write_FLAG(0xFF00 | chip->flag);
396 if (chip->cs_chg_udelay)
397 udelay(chip->cs_chg_udelay);
405 static void u16_writer(struct driver_data *drv_data)
407 pr_debug("cr16 is 0x%x\n", read_STAT());
408 while (drv_data->tx < drv_data->tx_end) {
409 write_TDBR(*(u16 *) (drv_data->tx));
410 while ((read_STAT() & BIT_STAT_TXS))
415 /* poll for SPI completion before returning */
416 while (!(read_STAT() & BIT_STAT_SPIF))
420 static void u16_cs_chg_writer(struct driver_data *drv_data)
422 struct chip_data *chip = drv_data->cur_chip;
424 while (drv_data->tx < drv_data->tx_end) {
425 write_FLAG(chip->flag);
428 write_TDBR(*(u16 *) (drv_data->tx));
429 while ((read_STAT() & BIT_STAT_TXS))
431 while (!(read_STAT() & BIT_STAT_SPIF))
433 write_FLAG(0xFF00 | chip->flag);
435 if (chip->cs_chg_udelay)
436 udelay(chip->cs_chg_udelay);
443 static void u16_reader(struct driver_data *drv_data)
445 pr_debug("cr-16 is 0x%x\n", read_STAT());
448 while (drv_data->rx < (drv_data->rx_end - 2)) {
449 while (!(read_STAT() & BIT_STAT_RXS))
451 *(u16 *) (drv_data->rx) = read_RDBR();
455 while (!(read_STAT() & BIT_STAT_RXS))
457 *(u16 *) (drv_data->rx) = read_SHAW();
461 static void u16_cs_chg_reader(struct driver_data *drv_data)
463 struct chip_data *chip = drv_data->cur_chip;
465 while (drv_data->rx < drv_data->rx_end) {
466 write_FLAG(chip->flag);
469 read_RDBR(); /* kick off */
470 while (!(read_STAT() & BIT_STAT_RXS))
472 while (!(read_STAT() & BIT_STAT_SPIF))
474 *(u16 *) (drv_data->rx) = read_SHAW();
475 write_FLAG(0xFF00 | chip->flag);
477 if (chip->cs_chg_udelay)
478 udelay(chip->cs_chg_udelay);
485 static void u16_duplex(struct driver_data *drv_data)
487 /* in duplex mode, clk is triggered by writing of TDBR */
488 while (drv_data->tx < drv_data->tx_end) {
489 write_TDBR(*(u16 *) (drv_data->tx));
490 while (!(read_STAT() & BIT_STAT_SPIF))
492 while (!(read_STAT() & BIT_STAT_RXS))
494 *(u16 *) (drv_data->rx) = read_RDBR();
500 static void u16_cs_chg_duplex(struct driver_data *drv_data)
502 struct chip_data *chip = drv_data->cur_chip;
504 while (drv_data->tx < drv_data->tx_end) {
505 write_FLAG(chip->flag);
508 write_TDBR(*(u16 *) (drv_data->tx));
509 while (!(read_STAT() & BIT_STAT_SPIF))
511 while (!(read_STAT() & BIT_STAT_RXS))
513 *(u16 *) (drv_data->rx) = read_RDBR();
514 write_FLAG(0xFF00 | chip->flag);
516 if (chip->cs_chg_udelay)
517 udelay(chip->cs_chg_udelay);
525 /* test if ther is more transfer to be done */
526 static void *next_transfer(struct driver_data *drv_data)
528 struct spi_message *msg = drv_data->cur_msg;
529 struct spi_transfer *trans = drv_data->cur_transfer;
531 /* Move to next transfer */
532 if (trans->transfer_list.next != &msg->transfers) {
533 drv_data->cur_transfer =
534 list_entry(trans->transfer_list.next,
535 struct spi_transfer, transfer_list);
536 return RUNNING_STATE;
542 * caller already set message->status;
543 * dma and pio irqs are blocked give finished message back
545 static void giveback(struct driver_data *drv_data)
547 struct spi_transfer *last_transfer;
549 struct spi_message *msg;
551 spin_lock_irqsave(&drv_data->lock, flags);
552 msg = drv_data->cur_msg;
553 drv_data->cur_msg = NULL;
554 drv_data->cur_transfer = NULL;
555 drv_data->cur_chip = NULL;
556 queue_work(drv_data->workqueue, &drv_data->pump_messages);
557 spin_unlock_irqrestore(&drv_data->lock, flags);
559 last_transfer = list_entry(msg->transfers.prev,
560 struct spi_transfer, transfer_list);
564 /* disable chip select signal. And not stop spi in autobuffer mode */
565 if (drv_data->tx_dma != 0xFFFF) {
567 bfin_spi_disable(drv_data);
571 msg->complete(msg->context);
574 static irqreturn_t dma_irq_handler(int irq, void *dev_id, struct pt_regs *regs)
576 struct driver_data *drv_data = (struct driver_data *)dev_id;
577 struct spi_message *msg = drv_data->cur_msg;
579 pr_debug("in dma_irq_handler\n");
580 clear_dma_irqstat(CH_SPI);
583 * wait for the last transaction shifted out. yes, these two
584 * while loops are supposed to be the same (see the HRM).
586 if (drv_data->tx != NULL) {
587 while (bfin_read_SPI_STAT() & TXS)
589 while (bfin_read_SPI_STAT() & TXS)
593 while (!(bfin_read_SPI_STAT() & SPIF))
596 bfin_spi_disable(drv_data);
598 msg->actual_length += drv_data->len_in_bytes;
600 /* Move to next transfer */
601 msg->state = next_transfer(drv_data);
603 /* Schedule transfer tasklet */
604 tasklet_schedule(&drv_data->pump_transfers);
606 /* free the irq handler before next transfer */
607 pr_debug("disable dma channel irq%d\n", CH_SPI);
608 dma_disable_irq(CH_SPI);
613 static void pump_transfers(unsigned long data)
615 struct driver_data *drv_data = (struct driver_data *)data;
616 struct spi_message *message = NULL;
617 struct spi_transfer *transfer = NULL;
618 struct spi_transfer *previous = NULL;
619 struct chip_data *chip = NULL;
620 u16 cr, width, dma_width, dma_config;
621 u32 tranf_success = 1;
623 /* Get current state information */
624 message = drv_data->cur_msg;
625 transfer = drv_data->cur_transfer;
626 chip = drv_data->cur_chip;
629 * if msg is error or done, report it back using complete() callback
632 /* Handle for abort */
633 if (message->state == ERROR_STATE) {
634 message->status = -EIO;
639 /* Handle end of message */
640 if (message->state == DONE_STATE) {
646 /* Delay if requested at end of transfer */
647 if (message->state == RUNNING_STATE) {
648 previous = list_entry(transfer->transfer_list.prev,
649 struct spi_transfer, transfer_list);
650 if (previous->delay_usecs)
651 udelay(previous->delay_usecs);
654 /* Setup the transfer state based on the type of transfer */
655 if (flush(drv_data) == 0) {
656 dev_err(&drv_data->pdev->dev, "pump_transfers: flush failed\n");
657 message->status = -EIO;
662 if (transfer->tx_buf != NULL) {
663 drv_data->tx = (void *)transfer->tx_buf;
664 drv_data->tx_end = drv_data->tx + transfer->len;
665 pr_debug("tx_buf is %p, tx_end is %p\n", transfer->tx_buf,
671 if (transfer->rx_buf != NULL) {
672 drv_data->rx = transfer->rx_buf;
673 drv_data->rx_end = drv_data->rx + transfer->len;
674 pr_debug("rx_buf is %p, rx_end is %p\n", transfer->rx_buf,
680 drv_data->rx_dma = transfer->rx_dma;
681 drv_data->tx_dma = transfer->tx_dma;
682 drv_data->len_in_bytes = transfer->len;
685 if (width == CFG_SPI_WORDSIZE16) {
686 drv_data->len = (transfer->len) >> 1;
688 drv_data->len = transfer->len;
690 drv_data->write = drv_data->tx ? chip->write : null_writer;
691 drv_data->read = drv_data->rx ? chip->read : null_reader;
692 drv_data->duplex = chip->duplex ? chip->duplex : null_writer;
694 ("transfer: drv_data->write is %p, chip->write is %p, null_wr is %p\n",
695 drv_data->write, chip->write, null_writer);
697 /* speed and width has been set on per message */
698 message->state = RUNNING_STATE;
701 /* restore spi status for each spi transfer */
702 if (transfer->speed_hz) {
703 write_BAUD(hz_to_spi_baud(transfer->speed_hz));
705 write_BAUD(chip->baud);
707 write_FLAG(chip->flag);
709 pr_debug("now pumping a transfer: width is %d, len is %d\n", width,
713 * Try to map dma buffer and do a dma transfer if
714 * successful use different way to r/w according to
715 * drv_data->cur_chip->enable_dma
717 if (drv_data->cur_chip->enable_dma && drv_data->len > 6) {
719 write_STAT(BIT_STAT_CLR);
721 clear_dma_irqstat(CH_SPI);
722 bfin_spi_disable(drv_data);
724 /* config dma channel */
725 pr_debug("doing dma transfer\n");
726 if (width == CFG_SPI_WORDSIZE16) {
727 set_dma_x_count(CH_SPI, drv_data->len);
728 set_dma_x_modify(CH_SPI, 2);
729 dma_width = WDSIZE_16;
731 set_dma_x_count(CH_SPI, drv_data->len);
732 set_dma_x_modify(CH_SPI, 1);
733 dma_width = WDSIZE_8;
736 /* set transfer width,direction. And enable spi */
737 cr = (read_CTRL() & (~BIT_CTL_TIMOD));
739 /* dirty hack for autobuffer DMA mode */
740 if (drv_data->tx_dma == 0xFFFF) {
741 pr_debug("doing autobuffer DMA out.\n");
743 /* no irq in autobuffer mode */
745 (DMAFLOW_AUTO | RESTART | dma_width | DI_EN);
746 set_dma_config(CH_SPI, dma_config);
747 set_dma_start_addr(CH_SPI, (unsigned long)drv_data->tx);
749 write_CTRL(cr | CFG_SPI_DMAWRITE | (width << 8) |
750 (CFG_SPI_ENABLE << 14));
752 /* just return here, there can only be one transfer in this mode */
758 /* In dma mode, rx or tx must be NULL in one transfer */
759 if (drv_data->rx != NULL) {
760 /* set transfer mode, and enable SPI */
761 pr_debug("doing DMA in.\n");
763 /* disable SPI before write to TDBR */
764 write_CTRL(cr & ~BIT_CTL_ENABLE);
766 /* clear tx reg soformer data is not shifted out */
769 set_dma_x_count(CH_SPI, drv_data->len);
772 dma_enable_irq(CH_SPI);
773 dma_config = (WNR | RESTART | dma_width | DI_EN);
774 set_dma_config(CH_SPI, dma_config);
775 set_dma_start_addr(CH_SPI, (unsigned long)drv_data->rx);
779 CFG_SPI_DMAREAD | (width << 8) | (CFG_SPI_ENABLE <<
781 /* set transfer mode, and enable SPI */
783 } else if (drv_data->tx != NULL) {
784 pr_debug("doing DMA out.\n");
787 dma_enable_irq(CH_SPI);
788 dma_config = (RESTART | dma_width | DI_EN);
789 set_dma_config(CH_SPI, dma_config);
790 set_dma_start_addr(CH_SPI, (unsigned long)drv_data->tx);
793 write_CTRL(cr | CFG_SPI_DMAWRITE | (width << 8) |
794 (CFG_SPI_ENABLE << 14));
798 /* IO mode write then read */
799 pr_debug("doing IO transfer\n");
801 write_STAT(BIT_STAT_CLR);
803 if (drv_data->tx != NULL && drv_data->rx != NULL) {
804 /* full duplex mode */
805 BUG_ON((drv_data->tx_end - drv_data->tx) !=
806 (drv_data->rx_end - drv_data->rx));
807 cr = (read_CTRL() & (~BIT_CTL_TIMOD)); /* clear the TIMOD bits */
809 CFG_SPI_WRITE | (width << 8) | (CFG_SPI_ENABLE <<
811 pr_debug("IO duplex: cr is 0x%x\n", cr);
816 drv_data->duplex(drv_data);
818 if (drv_data->tx != drv_data->tx_end)
820 } else if (drv_data->tx != NULL) {
821 /* write only half duplex */
822 cr = (read_CTRL() & (~BIT_CTL_TIMOD)); /* clear the TIMOD bits */
824 CFG_SPI_WRITE | (width << 8) | (CFG_SPI_ENABLE <<
826 pr_debug("IO write: cr is 0x%x\n", cr);
831 drv_data->write(drv_data);
833 if (drv_data->tx != drv_data->tx_end)
835 } else if (drv_data->rx != NULL) {
836 /* read only half duplex */
837 cr = (read_CTRL() & (~BIT_CTL_TIMOD)); /* cleare the TIMOD bits */
839 CFG_SPI_READ | (width << 8) | (CFG_SPI_ENABLE <<
841 pr_debug("IO read: cr is 0x%x\n", cr);
846 drv_data->read(drv_data);
847 if (drv_data->rx != drv_data->rx_end)
851 if (!tranf_success) {
852 pr_debug("IO write error!\n");
853 message->state = ERROR_STATE;
855 /* Update total byte transfered */
856 message->actual_length += drv_data->len;
858 /* Move to next transfer of this msg */
859 message->state = next_transfer(drv_data);
862 /* Schedule next transfer tasklet */
863 tasklet_schedule(&drv_data->pump_transfers);
868 /* pop a msg from queue and kick off real transfer */
869 static void pump_messages(struct work_struct *work)
871 struct driver_data *drv_data = container_of(work, struct driver_data, pump_messages);
874 /* Lock queue and check for queue work */
875 spin_lock_irqsave(&drv_data->lock, flags);
876 if (list_empty(&drv_data->queue) || drv_data->run == QUEUE_STOPPED) {
877 /* pumper kicked off but no work to do */
879 spin_unlock_irqrestore(&drv_data->lock, flags);
883 /* Make sure we are not already running a message */
884 if (drv_data->cur_msg) {
885 spin_unlock_irqrestore(&drv_data->lock, flags);
889 /* Extract head of queue */
890 drv_data->cur_msg = list_entry(drv_data->queue.next,
891 struct spi_message, queue);
892 list_del_init(&drv_data->cur_msg->queue);
894 /* Initial message state */
895 drv_data->cur_msg->state = START_STATE;
896 drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next,
897 struct spi_transfer, transfer_list);
899 /* Setup the SSP using the per chip configuration */
900 drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi);
901 restore_state(drv_data);
903 ("got a message to pump, state is set to: baud %d, flag 0x%x, ctl 0x%x\n",
904 drv_data->cur_chip->baud, drv_data->cur_chip->flag,
905 drv_data->cur_chip->ctl_reg);
906 pr_debug("the first transfer len is %d\n", drv_data->cur_transfer->len);
908 /* Mark as busy and launch transfers */
909 tasklet_schedule(&drv_data->pump_transfers);
912 spin_unlock_irqrestore(&drv_data->lock, flags);
916 * got a msg to transfer, queue it in drv_data->queue.
917 * And kick off message pumper
919 static int transfer(struct spi_device *spi, struct spi_message *msg)
921 struct driver_data *drv_data = spi_master_get_devdata(spi->master);
924 spin_lock_irqsave(&drv_data->lock, flags);
926 if (drv_data->run == QUEUE_STOPPED) {
927 spin_unlock_irqrestore(&drv_data->lock, flags);
931 msg->actual_length = 0;
932 msg->status = -EINPROGRESS;
933 msg->state = START_STATE;
935 pr_debug("adding an msg in transfer() \n");
936 list_add_tail(&msg->queue, &drv_data->queue);
938 if (drv_data->run == QUEUE_RUNNING && !drv_data->busy)
939 queue_work(drv_data->workqueue, &drv_data->pump_messages);
941 spin_unlock_irqrestore(&drv_data->lock, flags);
946 /* first setup for new devices */
947 static int setup(struct spi_device *spi)
949 struct bfin5xx_spi_chip *chip_info = NULL;
950 struct chip_data *chip;
951 struct driver_data *drv_data = spi_master_get_devdata(spi->master);
954 /* Abort device setup if requested features are not supported */
955 if (spi->mode & ~(SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST)) {
956 dev_err(&spi->dev, "requested mode not fully supported\n");
960 /* Zero (the default) here means 8 bits */
961 if (!spi->bits_per_word)
962 spi->bits_per_word = 8;
964 if (spi->bits_per_word != 8 && spi->bits_per_word != 16)
967 /* Only alloc (or use chip_info) on first setup */
968 chip = spi_get_ctldata(spi);
970 chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
974 chip->enable_dma = 0;
975 chip_info = spi->controller_data;
978 /* chip_info isn't always needed */
980 chip->enable_dma = chip_info->enable_dma != 0
981 && drv_data->master_info->enable_dma;
982 chip->ctl_reg = chip_info->ctl_reg;
983 chip->bits_per_word = chip_info->bits_per_word;
984 chip->cs_change_per_word = chip_info->cs_change_per_word;
985 chip->cs_chg_udelay = chip_info->cs_chg_udelay;
988 /* translate common spi framework into our register */
989 if (spi->mode & SPI_CPOL)
990 chip->ctl_reg |= CPOL;
991 if (spi->mode & SPI_CPHA)
992 chip->ctl_reg |= CPHA;
993 if (spi->mode & SPI_LSB_FIRST)
994 chip->ctl_reg |= LSBF;
995 /* we dont support running in slave mode (yet?) */
996 chip->ctl_reg |= MSTR;
999 * if any one SPI chip is registered and wants DMA, request the
1000 * DMA channel for it
1002 if (chip->enable_dma && !dma_requested) {
1003 /* register dma irq handler */
1004 if (request_dma(CH_SPI, "BF53x_SPI_DMA") < 0) {
1006 ("Unable to request BlackFin SPI DMA channel\n");
1009 if (set_dma_callback(CH_SPI, (void *)dma_irq_handler, drv_data)
1011 pr_debug("Unable to set dma callback\n");
1014 dma_disable_irq(CH_SPI);
1019 * Notice: for blackfin, the speed_hz is the value of register
1020 * SPI_BAUD, not the real baudrate
1022 chip->baud = hz_to_spi_baud(spi->max_speed_hz);
1023 spi_flg = ~(1 << (spi->chip_select));
1024 chip->flag = ((u16) spi_flg << 8) | (1 << (spi->chip_select));
1025 chip->chip_select_num = spi->chip_select;
1027 switch (chip->bits_per_word) {
1030 chip->width = CFG_SPI_WORDSIZE8;
1031 chip->read = chip->cs_change_per_word ?
1032 u8_cs_chg_reader : u8_reader;
1033 chip->write = chip->cs_change_per_word ?
1034 u8_cs_chg_writer : u8_writer;
1035 chip->duplex = chip->cs_change_per_word ?
1036 u8_cs_chg_duplex : u8_duplex;
1041 chip->width = CFG_SPI_WORDSIZE16;
1042 chip->read = chip->cs_change_per_word ?
1043 u16_cs_chg_reader : u16_reader;
1044 chip->write = chip->cs_change_per_word ?
1045 u16_cs_chg_writer : u16_writer;
1046 chip->duplex = chip->cs_change_per_word ?
1047 u16_cs_chg_duplex : u16_duplex;
1051 dev_err(&spi->dev, "%d bits_per_word is not supported\n",
1052 chip->bits_per_word);
1057 pr_debug("setup spi chip %s, width is %d, dma is %d,",
1058 spi->modalias, chip->width, chip->enable_dma);
1059 pr_debug("ctl_reg is 0x%x, flag_reg is 0x%x\n",
1060 chip->ctl_reg, chip->flag);
1062 spi_set_ctldata(spi, chip);
1068 * callback for spi framework.
1069 * clean driver specific data
1071 static void cleanup(const struct spi_device *spi)
1073 struct chip_data *chip = spi_get_ctldata((struct spi_device *)spi);
1078 static inline int init_queue(struct driver_data *drv_data)
1080 INIT_LIST_HEAD(&drv_data->queue);
1081 spin_lock_init(&drv_data->lock);
1083 drv_data->run = QUEUE_STOPPED;
1086 /* init transfer tasklet */
1087 tasklet_init(&drv_data->pump_transfers,
1088 pump_transfers, (unsigned long)drv_data);
1090 /* init messages workqueue */
1091 INIT_WORK(&drv_data->pump_messages, pump_messages);
1092 drv_data->workqueue =
1093 create_singlethread_workqueue(drv_data->master->cdev.dev->bus_id);
1094 if (drv_data->workqueue == NULL)
1100 static inline int start_queue(struct driver_data *drv_data)
1102 unsigned long flags;
1104 spin_lock_irqsave(&drv_data->lock, flags);
1106 if (drv_data->run == QUEUE_RUNNING || drv_data->busy) {
1107 spin_unlock_irqrestore(&drv_data->lock, flags);
1111 drv_data->run = QUEUE_RUNNING;
1112 drv_data->cur_msg = NULL;
1113 drv_data->cur_transfer = NULL;
1114 drv_data->cur_chip = NULL;
1115 spin_unlock_irqrestore(&drv_data->lock, flags);
1117 queue_work(drv_data->workqueue, &drv_data->pump_messages);
1122 static inline int stop_queue(struct driver_data *drv_data)
1124 unsigned long flags;
1125 unsigned limit = 500;
1128 spin_lock_irqsave(&drv_data->lock, flags);
1131 * This is a bit lame, but is optimized for the common execution path.
1132 * A wait_queue on the drv_data->busy could be used, but then the common
1133 * execution path (pump_messages) would be required to call wake_up or
1134 * friends on every SPI message. Do this instead
1136 drv_data->run = QUEUE_STOPPED;
1137 while (!list_empty(&drv_data->queue) && drv_data->busy && limit--) {
1138 spin_unlock_irqrestore(&drv_data->lock, flags);
1140 spin_lock_irqsave(&drv_data->lock, flags);
1143 if (!list_empty(&drv_data->queue) || drv_data->busy)
1146 spin_unlock_irqrestore(&drv_data->lock, flags);
1151 static inline int destroy_queue(struct driver_data *drv_data)
1155 status = stop_queue(drv_data);
1159 destroy_workqueue(drv_data->workqueue);
1164 static int __init bfin5xx_spi_probe(struct platform_device *pdev)
1166 struct device *dev = &pdev->dev;
1167 struct bfin5xx_spi_master *platform_info;
1168 struct spi_master *master;
1169 struct driver_data *drv_data = 0;
1172 platform_info = dev->platform_data;
1174 /* Allocate master with space for drv_data */
1175 master = spi_alloc_master(dev, sizeof(struct driver_data) + 16);
1177 dev_err(&pdev->dev, "can not alloc spi_master\n");
1180 drv_data = spi_master_get_devdata(master);
1181 drv_data->master = master;
1182 drv_data->master_info = platform_info;
1183 drv_data->pdev = pdev;
1185 master->bus_num = pdev->id;
1186 master->num_chipselect = platform_info->num_chipselect;
1187 master->cleanup = cleanup;
1188 master->setup = setup;
1189 master->transfer = transfer;
1191 /* Initial and start queue */
1192 status = init_queue(drv_data);
1194 dev_err(&pdev->dev, "problem initializing queue\n");
1195 goto out_error_queue_alloc;
1197 status = start_queue(drv_data);
1199 dev_err(&pdev->dev, "problem starting queue\n");
1200 goto out_error_queue_alloc;
1203 /* Register with the SPI framework */
1204 platform_set_drvdata(pdev, drv_data);
1205 status = spi_register_master(master);
1207 dev_err(&pdev->dev, "problem registering spi master\n");
1208 goto out_error_queue_alloc;
1210 pr_debug("controller probe successfully\n");
1213 out_error_queue_alloc:
1214 destroy_queue(drv_data);
1215 spi_master_put(master);
1219 /* stop hardware and remove the driver */
1220 static int __devexit bfin5xx_spi_remove(struct platform_device *pdev)
1222 struct driver_data *drv_data = platform_get_drvdata(pdev);
1228 /* Remove the queue */
1229 status = destroy_queue(drv_data);
1233 /* Disable the SSP at the peripheral and SOC level */
1234 bfin_spi_disable(drv_data);
1237 if (drv_data->master_info->enable_dma) {
1238 if (dma_channel_active(CH_SPI))
1242 /* Disconnect from the SPI framework */
1243 spi_unregister_master(drv_data->master);
1245 /* Prevent double remove */
1246 platform_set_drvdata(pdev, NULL);
1252 static int bfin5xx_spi_suspend(struct platform_device *pdev, pm_message_t state)
1254 struct driver_data *drv_data = platform_get_drvdata(pdev);
1257 status = stop_queue(drv_data);
1262 bfin_spi_disable(drv_data);
1267 static int bfin5xx_spi_resume(struct platform_device *pdev)
1269 struct driver_data *drv_data = platform_get_drvdata(pdev);
1272 /* Enable the SPI interface */
1273 bfin_spi_enable(drv_data);
1275 /* Start the queue running */
1276 status = start_queue(drv_data);
1278 dev_err(&pdev->dev, "problem starting queue (%d)\n", status);
1285 #define bfin5xx_spi_suspend NULL
1286 #define bfin5xx_spi_resume NULL
1287 #endif /* CONFIG_PM */
1289 static struct platform_driver bfin5xx_spi_driver = {
1291 .name = "bfin-spi-master",
1292 .bus = &platform_bus_type,
1293 .owner = THIS_MODULE,
1295 .probe = bfin5xx_spi_probe,
1296 .remove = __devexit_p(bfin5xx_spi_remove),
1297 .suspend = bfin5xx_spi_suspend,
1298 .resume = bfin5xx_spi_resume,
1301 static int __init bfin5xx_spi_init(void)
1303 return platform_driver_register(&bfin5xx_spi_driver);
1306 module_init(bfin5xx_spi_init);
1308 static void __exit bfin5xx_spi_exit(void)
1310 platform_driver_unregister(&bfin5xx_spi_driver);
1313 module_exit(bfin5xx_spi_exit);