Blackfin SPI driver: reconfigure speed_hz and bits_per_word in each spi transfer
authorBryan Wu <bryan.wu@analog.com>
Wed, 5 Dec 2007 07:45:23 +0000 (23:45 -0800)
committerLinus Torvalds <torvalds@woody.linux-foundation.org>
Wed, 5 Dec 2007 17:21:20 +0000 (09:21 -0800)
 - reconfigure SPI baud from speed_hz of each spi transfer
 - according to spi_transfer.bits_per_word to reprogram register and setup
   correct SPI operation handlers

Signed-off-by: Bryan Wu <bryan.wu@analog.com>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/spi/spi_bfin5xx.c

index d6e9812538c4f301192ea689375f0d6c40d09b45..22697b812205725829ae33f2fbf7308604834b2f 100644 (file)
@@ -234,10 +234,8 @@ static int restore_state(struct driver_data *drv_data)
        dev_dbg(&drv_data->pdev->dev, "restoring spi ctl state\n");
 
        /* Load the registers */
-       write_BAUD(drv_data, chip->baud);
-       chip->ctl_reg &= (~BIT_CTL_TIMOD);
-       chip->ctl_reg |= (chip->width << 8);
        write_CTRL(drv_data, chip->ctl_reg);
+       write_BAUD(drv_data, chip->baud);
 
        bfin_spi_enable(drv_data);
        cs_active(drv_data, chip);
@@ -679,6 +677,7 @@ static void pump_transfers(unsigned long data)
        message = drv_data->cur_msg;
        transfer = drv_data->cur_transfer;
        chip = drv_data->cur_chip;
+
        /*
         * if msg is error or done, report it back using complete() callback
         */
@@ -736,15 +735,48 @@ static void pump_transfers(unsigned long data)
        drv_data->len_in_bytes = transfer->len;
        drv_data->cs_change = transfer->cs_change;
 
-       width = chip->width;
+       /* Bits per word setup */
+       switch (transfer->bits_per_word) {
+       case 8:
+               drv_data->n_bytes = 1;
+               width = CFG_SPI_WORDSIZE8;
+               drv_data->read = chip->cs_change_per_word ?
+                       u8_cs_chg_reader : u8_reader;
+               drv_data->write = chip->cs_change_per_word ?
+                       u8_cs_chg_writer : u8_writer;
+               drv_data->duplex = chip->cs_change_per_word ?
+                       u8_cs_chg_duplex : u8_duplex;
+               break;
+
+       case 16:
+               drv_data->n_bytes = 2;
+               width = CFG_SPI_WORDSIZE16;
+               drv_data->read = chip->cs_change_per_word ?
+                       u16_cs_chg_reader : u16_reader;
+               drv_data->write = chip->cs_change_per_word ?
+                       u16_cs_chg_writer : u16_writer;
+               drv_data->duplex = chip->cs_change_per_word ?
+                       u16_cs_chg_duplex : u16_duplex;
+               break;
+
+       default:
+               /* No change, the same as default setting */
+               drv_data->n_bytes = chip->n_bytes;
+               width = chip->width;
+               drv_data->write = drv_data->tx ? chip->write : null_writer;
+               drv_data->read = drv_data->rx ? chip->read : null_reader;
+               drv_data->duplex = chip->duplex ? chip->duplex : null_writer;
+               break;
+       }
+       cr = (read_CTRL(drv_data) & (~BIT_CTL_TIMOD));
+       cr |= (width << 8);
+       write_CTRL(drv_data, cr);
+
        if (width == CFG_SPI_WORDSIZE16) {
                drv_data->len = (transfer->len) >> 1;
        } else {
                drv_data->len = transfer->len;
        }
-       drv_data->write = drv_data->tx ? chip->write : null_writer;
-       drv_data->read = drv_data->rx ? chip->read : null_reader;
-       drv_data->duplex = chip->duplex ? chip->duplex : null_writer;
        dev_dbg(&drv_data->pdev->dev, "transfer: ",
                "drv_data->write is %p, chip->write is %p, null_wr is %p\n",
                drv_data->write, chip->write, null_writer);
@@ -753,6 +785,12 @@ static void pump_transfers(unsigned long data)
        message->state = RUNNING_STATE;
        dma_config = 0;
 
+       /* Speed setup (surely valid because already checked) */
+       if (transfer->speed_hz)
+               write_BAUD(drv_data, hz_to_spi_baud(transfer->speed_hz));
+       else
+               write_BAUD(drv_data, chip->baud);
+
        write_STAT(drv_data, BIT_STAT_CLR);
        cr = (read_CTRL(drv_data) & (~BIT_CTL_TIMOD));
        cs_active(drv_data, chip);