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         u8 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 static void bfin_spi_enable(struct driver_data *drv_data)
 
 144         write_CTRL(cr | BIT_CTL_ENABLE);
 
 148 static 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)
 
 169 static int flush(struct driver_data *drv_data)
 
 171         unsigned long limit = loops_per_jiffy << 1;
 
 173         /* wait for stop and clear stat */
 
 174         while (!(read_STAT() & BIT_STAT_SPIF) && limit--)
 
 177         write_STAT(BIT_STAT_CLR);
 
 182 /* stop controller and re-config current chip*/
 
 183 static void restore_state(struct driver_data *drv_data)
 
 185         struct chip_data *chip = drv_data->cur_chip;
 
 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");
 
 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);
 
 196         switch (chip->chip_select_num) {
 
 198                 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3c00);
 
 204                 bfin_write_PORT_MUX(bfin_read_PORT_MUX() | PJSE_SPI);
 
 206                 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3800);
 
 211                 bfin_write_PORT_MUX(bfin_read_PORT_MUX() | PFS4E_SPI);
 
 213                 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3840);
 
 218                 bfin_write_PORT_MUX(bfin_read_PORT_MUX() | PFS5E_SPI);
 
 220                 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3820);
 
 225                 bfin_write_PORT_MUX(bfin_read_PORT_MUX() | PFS6E_SPI);
 
 227                 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3810);
 
 232                 bfin_write_PORT_MUX(bfin_read_PORT_MUX() | PJCE_SPI);
 
 234                 bfin_write_PORTF_FER(bfin_read_PORTF_FER() | 0x3800);
 
 240         /* Load the registers */
 
 241         write_CTRL(chip->ctl_reg);
 
 242         write_BAUD(chip->baud);
 
 243         write_FLAG(chip->flag);
 
 246 /* used to kick off transfer in rx mode */
 
 247 static unsigned short dummy_read(void)
 
 254 static void null_writer(struct driver_data *drv_data)
 
 256         u8 n_bytes = drv_data->n_bytes;
 
 258         while (drv_data->tx < drv_data->tx_end) {
 
 260                 while ((read_STAT() & BIT_STAT_TXS))
 
 262                 drv_data->tx += n_bytes;
 
 266 static void null_reader(struct driver_data *drv_data)
 
 268         u8 n_bytes = drv_data->n_bytes;
 
 271         while (drv_data->rx < drv_data->rx_end) {
 
 272                 while (!(read_STAT() & BIT_STAT_RXS))
 
 275                 drv_data->rx += n_bytes;
 
 279 static void u8_writer(struct driver_data *drv_data)
 
 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)
 
 290         /* poll for SPI completion before returning */
 
 291         while (!(read_STAT() & BIT_STAT_SPIF))
 
 295 static void u8_cs_chg_writer(struct driver_data *drv_data)
 
 297         struct chip_data *chip = drv_data->cur_chip;
 
 299         while (drv_data->tx < drv_data->tx_end) {
 
 300                 write_FLAG(chip->flag);
 
 303                 write_TDBR(*(u8 *) (drv_data->tx));
 
 304                 while (read_STAT() & BIT_STAT_TXS)
 
 306                 while (!(read_STAT() & BIT_STAT_SPIF))
 
 308                 write_FLAG(0xFF00 | chip->flag);
 
 310                 if (chip->cs_chg_udelay)
 
 311                         udelay(chip->cs_chg_udelay);
 
 318 static void u8_reader(struct driver_data *drv_data)
 
 320         dev_dbg(&drv_data->pdev->dev, 
 
 321                 "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         dev_dbg(&drv_data->pdev->dev, 
 
 408                 "cr16 is 0x%x\n", read_STAT());
 
 410         while (drv_data->tx < drv_data->tx_end) {
 
 411                 write_TDBR(*(u16 *) (drv_data->tx));
 
 412                 while ((read_STAT() & BIT_STAT_TXS))
 
 417         /* poll for SPI completion before returning */
 
 418         while (!(read_STAT() & BIT_STAT_SPIF))
 
 422 static void u16_cs_chg_writer(struct driver_data *drv_data)
 
 424         struct chip_data *chip = drv_data->cur_chip;
 
 426         while (drv_data->tx < drv_data->tx_end) {
 
 427                 write_FLAG(chip->flag);
 
 430                 write_TDBR(*(u16 *) (drv_data->tx));
 
 431                 while ((read_STAT() & BIT_STAT_TXS))
 
 433                 while (!(read_STAT() & BIT_STAT_SPIF))
 
 435                 write_FLAG(0xFF00 | chip->flag);
 
 437                 if (chip->cs_chg_udelay)
 
 438                         udelay(chip->cs_chg_udelay);
 
 445 static void u16_reader(struct driver_data *drv_data)
 
 447         dev_dbg(&drv_data->pdev->dev,
 
 448                 "cr-16 is 0x%x\n", read_STAT());
 
 451         while (drv_data->rx < (drv_data->rx_end - 2)) {
 
 452                 while (!(read_STAT() & BIT_STAT_RXS))
 
 454                 *(u16 *) (drv_data->rx) = read_RDBR();
 
 458         while (!(read_STAT() & BIT_STAT_RXS))
 
 460         *(u16 *) (drv_data->rx) = read_SHAW();
 
 464 static void u16_cs_chg_reader(struct driver_data *drv_data)
 
 466         struct chip_data *chip = drv_data->cur_chip;
 
 468         while (drv_data->rx < drv_data->rx_end) {
 
 469                 write_FLAG(chip->flag);
 
 472                 read_RDBR();    /* kick off */
 
 473                 while (!(read_STAT() & BIT_STAT_RXS))
 
 475                 while (!(read_STAT() & BIT_STAT_SPIF))
 
 477                 *(u16 *) (drv_data->rx) = read_SHAW();
 
 478                 write_FLAG(0xFF00 | chip->flag);
 
 480                 if (chip->cs_chg_udelay)
 
 481                         udelay(chip->cs_chg_udelay);
 
 488 static void u16_duplex(struct driver_data *drv_data)
 
 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))
 
 495                 while (!(read_STAT() & BIT_STAT_RXS))
 
 497                 *(u16 *) (drv_data->rx) = read_RDBR();
 
 503 static void u16_cs_chg_duplex(struct driver_data *drv_data)
 
 505         struct chip_data *chip = drv_data->cur_chip;
 
 507         while (drv_data->tx < drv_data->tx_end) {
 
 508                 write_FLAG(chip->flag);
 
 511                 write_TDBR(*(u16 *) (drv_data->tx));
 
 512                 while (!(read_STAT() & BIT_STAT_SPIF))
 
 514                 while (!(read_STAT() & BIT_STAT_RXS))
 
 516                 *(u16 *) (drv_data->rx) = read_RDBR();
 
 517                 write_FLAG(0xFF00 | chip->flag);
 
 519                 if (chip->cs_chg_udelay)
 
 520                         udelay(chip->cs_chg_udelay);
 
 528 /* test if ther is more transfer to be done */
 
 529 static void *next_transfer(struct driver_data *drv_data)
 
 531         struct spi_message *msg = drv_data->cur_msg;
 
 532         struct spi_transfer *trans = drv_data->cur_transfer;
 
 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;
 
 545  * caller already set message->status;
 
 546  * dma and pio irqs are blocked give finished message back
 
 548 static void giveback(struct driver_data *drv_data)
 
 550         struct spi_transfer *last_transfer;
 
 552         struct spi_message *msg;
 
 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);
 
 562         last_transfer = list_entry(msg->transfers.prev,
 
 563                                    struct spi_transfer, transfer_list);
 
 567         /* disable chip select signal. And not stop spi in autobuffer mode */
 
 568         if (drv_data->tx_dma != 0xFFFF) {
 
 570                 bfin_spi_disable(drv_data);
 
 574                 msg->complete(msg->context);
 
 577 static irqreturn_t dma_irq_handler(int irq, void *dev_id)
 
 579         struct driver_data *drv_data = (struct driver_data *)dev_id;
 
 580         struct spi_message *msg = drv_data->cur_msg;
 
 582         dev_dbg(&drv_data->pdev->dev, "in dma_irq_handler\n");
 
 583         clear_dma_irqstat(CH_SPI);
 
 586          * wait for the last transaction shifted out.  yes, these two
 
 587          * while loops are supposed to be the same (see the HRM).
 
 589         if (drv_data->tx != NULL) {
 
 590                 while (bfin_read_SPI_STAT() & TXS)
 
 592                 while (bfin_read_SPI_STAT() & TXS)
 
 596         while (!(bfin_read_SPI_STAT() & SPIF))
 
 599         bfin_spi_disable(drv_data);
 
 601         msg->actual_length += drv_data->len_in_bytes;
 
 603         /* Move to next transfer */
 
 604         msg->state = next_transfer(drv_data);
 
 606         /* Schedule transfer tasklet */
 
 607         tasklet_schedule(&drv_data->pump_transfers);
 
 609         /* free the irq handler before next transfer */
 
 610         dev_dbg(&drv_data->pdev->dev,
 
 611                 "disable dma channel irq%d\n",
 
 613         dma_disable_irq(CH_SPI);
 
 618 static void pump_transfers(unsigned long data)
 
 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;
 
 626         u16 cr, dma_width, dma_config;
 
 627         u32 tranf_success = 1;
 
 629         /* Get current state information */
 
 630         message = drv_data->cur_msg;
 
 631         transfer = drv_data->cur_transfer;
 
 632         chip = drv_data->cur_chip;
 
 635          * if msg is error or done, report it back using complete() callback
 
 638          /* Handle for abort */
 
 639         if (message->state == ERROR_STATE) {
 
 640                 message->status = -EIO;
 
 645         /* Handle end of message */
 
 646         if (message->state == DONE_STATE) {
 
 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);
 
 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;
 
 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);
 
 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);
 
 686         drv_data->rx_dma = transfer->rx_dma;
 
 687         drv_data->tx_dma = transfer->tx_dma;
 
 688         drv_data->len_in_bytes = transfer->len;
 
 691         if (width == CFG_SPI_WORDSIZE16) {
 
 692                 drv_data->len = (transfer->len) >> 1;
 
 694                 drv_data->len = transfer->len;
 
 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);
 
 703         /* speed and width has been set on per message */
 
 704         message->state = RUNNING_STATE;
 
 707         /* restore spi status for each spi transfer */
 
 708         if (transfer->speed_hz) {
 
 709                 write_BAUD(hz_to_spi_baud(transfer->speed_hz));
 
 711                 write_BAUD(chip->baud);
 
 713         write_FLAG(chip->flag);
 
 715         dev_dbg(&drv_data->pdev->dev,
 
 716                 "now pumping a transfer: width is %d, len is %d\n",
 
 717                 width, transfer->len);
 
 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
 
 724         if (drv_data->cur_chip->enable_dma && drv_data->len > 6) {
 
 726                 write_STAT(BIT_STAT_CLR);
 
 728                 clear_dma_irqstat(CH_SPI);
 
 729                 bfin_spi_disable(drv_data);
 
 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;
 
 738                         set_dma_x_count(CH_SPI, drv_data->len);
 
 739                         set_dma_x_modify(CH_SPI, 1);
 
 740                         dma_width = WDSIZE_8;
 
 743                 /* set transfer width,direction. And enable spi */
 
 744                 cr = (read_CTRL() & (~BIT_CTL_TIMOD));
 
 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");
 
 751                         /* no irq in autobuffer mode */
 
 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);
 
 757                         write_CTRL(cr | CFG_SPI_DMAWRITE | (width << 8) |
 
 758                                    (CFG_SPI_ENABLE << 14));
 
 760                         /* just return here, there can only be one transfer in this mode */
 
 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");
 
 771                         /* disable SPI before write to TDBR */
 
 772                         write_CTRL(cr & ~BIT_CTL_ENABLE);
 
 774                         /* clear tx reg soformer data is not shifted out */
 
 777                         set_dma_x_count(CH_SPI, drv_data->len);
 
 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);
 
 787                             CFG_SPI_DMAREAD | (width << 8) | (CFG_SPI_ENABLE <<
 
 789                         /* set transfer mode, and enable SPI */
 
 791                 } else if (drv_data->tx != NULL) {
 
 792                         dev_dbg(&drv_data->pdev->dev, "doing DMA out.\n");
 
 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);
 
 801                         write_CTRL(cr | CFG_SPI_DMAWRITE | (width << 8) |
 
 802                                    (CFG_SPI_ENABLE << 14));
 
 806                 /* IO mode write then read */
 
 807                 dev_dbg(&drv_data->pdev->dev, "doing IO transfer\n");
 
 809                 write_STAT(BIT_STAT_CLR);
 
 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);
 
 824                         drv_data->duplex(drv_data);
 
 826                         if (drv_data->tx != drv_data->tx_end)
 
 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);
 
 839                         drv_data->write(drv_data);
 
 841                         if (drv_data->tx != drv_data->tx_end)
 
 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);
 
 854                         drv_data->read(drv_data);
 
 855                         if (drv_data->rx != drv_data->rx_end)
 
 859                 if (!tranf_success) {
 
 860                         dev_dbg(&drv_data->pdev->dev, 
 
 861                                 "IO write error!\n");
 
 862                         message->state = ERROR_STATE;
 
 864                         /* Update total byte transfered */
 
 865                         message->actual_length += drv_data->len;
 
 867                         /* Move to next transfer of this msg */
 
 868                         message->state = next_transfer(drv_data);
 
 871                 /* Schedule next transfer tasklet */
 
 872                 tasklet_schedule(&drv_data->pump_transfers);
 
 877 /* pop a msg from queue and kick off real transfer */
 
 878 static void pump_messages(struct work_struct *work)
 
 880         struct driver_data *drv_data = container_of(work, struct driver_data, pump_messages);
 
 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 */
 
 888                 spin_unlock_irqrestore(&drv_data->lock, flags);
 
 892         /* Make sure we are not already running a message */
 
 893         if (drv_data->cur_msg) {
 
 894                 spin_unlock_irqrestore(&drv_data->lock, flags);
 
 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);
 
 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);
 
 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);
 
 916         dev_dbg(&drv_data->pdev->dev, 
 
 917                 "the first transfer len is %d\n",
 
 918                 drv_data->cur_transfer->len);
 
 920         /* Mark as busy and launch transfers */
 
 921         tasklet_schedule(&drv_data->pump_transfers);
 
 924         spin_unlock_irqrestore(&drv_data->lock, flags);
 
 928  * got a msg to transfer, queue it in drv_data->queue.
 
 929  * And kick off message pumper
 
 931 static int transfer(struct spi_device *spi, struct spi_message *msg)
 
 933         struct driver_data *drv_data = spi_master_get_devdata(spi->master);
 
 936         spin_lock_irqsave(&drv_data->lock, flags);
 
 938         if (drv_data->run == QUEUE_STOPPED) {
 
 939                 spin_unlock_irqrestore(&drv_data->lock, flags);
 
 943         msg->actual_length = 0;
 
 944         msg->status = -EINPROGRESS;
 
 945         msg->state = START_STATE;
 
 947         dev_dbg(&spi->dev, "adding an msg in transfer() \n");
 
 948         list_add_tail(&msg->queue, &drv_data->queue);
 
 950         if (drv_data->run == QUEUE_RUNNING && !drv_data->busy)
 
 951                 queue_work(drv_data->workqueue, &drv_data->pump_messages);
 
 953         spin_unlock_irqrestore(&drv_data->lock, flags);
 
 958 /* first setup for new devices */
 
 959 static int setup(struct spi_device *spi)
 
 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);
 
 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");
 
 972         /* Zero (the default) here means 8 bits */
 
 973         if (!spi->bits_per_word)
 
 974                 spi->bits_per_word = 8;
 
 976         if (spi->bits_per_word != 8 && spi->bits_per_word != 16)
 
 979         /* Only alloc (or use chip_info) on first setup */
 
 980         chip = spi_get_ctldata(spi);
 
 982                 chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
 
 986                 chip->enable_dma = 0;
 
 987                 chip_info = spi->controller_data;
 
 990         /* chip_info isn't always needed */
 
 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;
 
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;
 
1011          * if any one SPI chip is registered and wants DMA, request the
 
1012          * DMA channel for it
 
1014         if (chip->enable_dma && !dma_requested) {
 
1015                 /* register dma irq handler */
 
1016                 if (request_dma(CH_SPI, "BF53x_SPI_DMA") < 0) {
 
1018                                 "Unable to request BlackFin SPI DMA channel\n");
 
1021                 if (set_dma_callback(CH_SPI, (void *)dma_irq_handler, drv_data)
 
1023                         dev_dbg(&spi->dev, "Unable to set dma callback\n");
 
1026                 dma_disable_irq(CH_SPI);
 
1031          * Notice: for blackfin, the speed_hz is the value of register
 
1032          * SPI_BAUD, not the real baudrate
 
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;
 
1039         switch (chip->bits_per_word) {
 
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;
 
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;
 
1063                 dev_err(&spi->dev, "%d bits_per_word is not supported\n",
 
1064                                 chip->bits_per_word);
 
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);
 
1074         spi_set_ctldata(spi, chip);
 
1080  * callback for spi framework.
 
1081  * clean driver specific data
 
1083 static void cleanup(struct spi_device *spi)
 
1085         struct chip_data *chip = spi_get_ctldata((struct spi_device *)spi);
 
1090 static inline int init_queue(struct driver_data *drv_data)
 
1092         INIT_LIST_HEAD(&drv_data->queue);
 
1093         spin_lock_init(&drv_data->lock);
 
1095         drv_data->run = QUEUE_STOPPED;
 
1098         /* init transfer tasklet */
 
1099         tasklet_init(&drv_data->pump_transfers,
 
1100                      pump_transfers, (unsigned long)drv_data);
 
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)
 
1112 static inline int start_queue(struct driver_data *drv_data)
 
1114         unsigned long flags;
 
1116         spin_lock_irqsave(&drv_data->lock, flags);
 
1118         if (drv_data->run == QUEUE_RUNNING || drv_data->busy) {
 
1119                 spin_unlock_irqrestore(&drv_data->lock, flags);
 
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);
 
1129         queue_work(drv_data->workqueue, &drv_data->pump_messages);
 
1134 static inline int stop_queue(struct driver_data *drv_data)
 
1136         unsigned long flags;
 
1137         unsigned limit = 500;
 
1140         spin_lock_irqsave(&drv_data->lock, flags);
 
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
 
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);
 
1152                 spin_lock_irqsave(&drv_data->lock, flags);
 
1155         if (!list_empty(&drv_data->queue) || drv_data->busy)
 
1158         spin_unlock_irqrestore(&drv_data->lock, flags);
 
1163 static inline int destroy_queue(struct driver_data *drv_data)
 
1167         status = stop_queue(drv_data);
 
1171         destroy_workqueue(drv_data->workqueue);
 
1176 static int __init bfin5xx_spi_probe(struct platform_device *pdev)
 
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;
 
1184         platform_info = dev->platform_data;
 
1186         /* Allocate master with space for drv_data */
 
1187         master = spi_alloc_master(dev, sizeof(struct driver_data) + 16);
 
1189                 dev_err(&pdev->dev, "can not alloc spi_master\n");
 
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;
 
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;
 
1203         /* Initial and start queue */
 
1204         status = init_queue(drv_data);
 
1206                 dev_err(&pdev->dev, "problem initializing queue\n");
 
1207                 goto out_error_queue_alloc;
 
1209         status = start_queue(drv_data);
 
1211                 dev_err(&pdev->dev, "problem starting queue\n");
 
1212                 goto out_error_queue_alloc;
 
1215         /* Register with the SPI framework */
 
1216         platform_set_drvdata(pdev, drv_data);
 
1217         status = spi_register_master(master);
 
1219                 dev_err(&pdev->dev, "problem registering spi master\n");
 
1220                 goto out_error_queue_alloc;
 
1222         dev_dbg(&pdev->dev, "controller probe successfully\n");
 
1225       out_error_queue_alloc:
 
1226         destroy_queue(drv_data);
 
1227         spi_master_put(master);
 
1231 /* stop hardware and remove the driver */
 
1232 static int __devexit bfin5xx_spi_remove(struct platform_device *pdev)
 
1234         struct driver_data *drv_data = platform_get_drvdata(pdev);
 
1240         /* Remove the queue */
 
1241         status = destroy_queue(drv_data);
 
1245         /* Disable the SSP at the peripheral and SOC level */
 
1246         bfin_spi_disable(drv_data);
 
1249         if (drv_data->master_info->enable_dma) {
 
1250                 if (dma_channel_active(CH_SPI))
 
1254         /* Disconnect from the SPI framework */
 
1255         spi_unregister_master(drv_data->master);
 
1257         /* Prevent double remove */
 
1258         platform_set_drvdata(pdev, NULL);
 
1264 static int bfin5xx_spi_suspend(struct platform_device *pdev, pm_message_t state)
 
1266         struct driver_data *drv_data = platform_get_drvdata(pdev);
 
1269         status = stop_queue(drv_data);
 
1274         bfin_spi_disable(drv_data);
 
1279 static int bfin5xx_spi_resume(struct platform_device *pdev)
 
1281         struct driver_data *drv_data = platform_get_drvdata(pdev);
 
1284         /* Enable the SPI interface */
 
1285         bfin_spi_enable(drv_data);
 
1287         /* Start the queue running */
 
1288         status = start_queue(drv_data);
 
1290                 dev_err(&pdev->dev, "problem starting queue (%d)\n", status);
 
1297 #define bfin5xx_spi_suspend NULL
 
1298 #define bfin5xx_spi_resume NULL
 
1299 #endif                          /* CONFIG_PM */
 
1301 static struct platform_driver bfin5xx_spi_driver = {
 
1303                 .name   = "bfin-spi-master",
 
1304                 .owner  = THIS_MODULE,
 
1306         .suspend        = bfin5xx_spi_suspend,
 
1307         .resume         = bfin5xx_spi_resume,
 
1308         .remove         = __devexit_p(bfin5xx_spi_remove),
 
1311 static int __init bfin5xx_spi_init(void)
 
1313         return platform_driver_probe(&bfin5xx_spi_driver, bfin5xx_spi_probe);
 
1315 module_init(bfin5xx_spi_init);
 
1317 static void __exit bfin5xx_spi_exit(void)
 
1319         platform_driver_unregister(&bfin5xx_spi_driver);
 
1321 module_exit(bfin5xx_spi_exit);