From: Bryan Wu <[EMAIL PROTECTED]>

Full duplex SPI operation should not read a dummy byte at the first
transfer.  Bug and fix by Jean-Christian de Rivaz <[EMAIL PROTECTED]>:

http://blackfin.uclinux.org/gf/project/uclinux-dist/tracker/?action=TrackerItemEdit&tracker_item_id=3678

Signed-off-by: Jean-Christian de Rivaz <[EMAIL PROTECTED]>
Signed-off-by: Bryan Wu <[EMAIL PROTECTED]>
Signed-off-by: David Brownell <[EMAIL PROTECTED]>
---
 drivers/spi/spi_bfin5xx.c |   18 +++---------------
 1 file changed, 3 insertions(+), 15 deletions(-)

--- g26.orig/drivers/spi/spi_bfin5xx.c  2008-01-31 11:52:00.000000000 -0800
+++ g26/drivers/spi/spi_bfin5xx.c       2008-01-31 11:52:01.000000000 -0800
@@ -358,14 +358,10 @@ static void u8_cs_chg_reader(struct driv
 
 static void u8_duplex(struct driver_data *drv_data)
 {
-       /* poll for SPI completion before start */
-       while (!(read_STAT(drv_data) & BIT_STAT_SPIF))
-               cpu_relax();
-
        /* in duplex mode, clk is triggered by writing of TDBR */
        while (drv_data->rx < drv_data->rx_end) {
                write_TDBR(drv_data, (*(u8 *) (drv_data->tx)));
-               while (read_STAT(drv_data) & BIT_STAT_TXS)
+               while (!(read_STAT(drv_data) & BIT_STAT_SPIF))
                        cpu_relax();
                while (!(read_STAT(drv_data) & BIT_STAT_RXS))
                        cpu_relax();
@@ -495,14 +491,10 @@ static void u16_cs_chg_reader(struct dri
 
 static void u16_duplex(struct driver_data *drv_data)
 {
-       /* poll for SPI completion before start */
-       while (!(read_STAT(drv_data) & BIT_STAT_SPIF))
-               cpu_relax();
-
        /* in duplex mode, clk is triggered by writing of TDBR */
        while (drv_data->tx < drv_data->tx_end) {
                write_TDBR(drv_data, (*(u16 *) (drv_data->tx)));
-               while (read_STAT(drv_data) & BIT_STAT_TXS)
+               while (!(read_STAT(drv_data) & BIT_STAT_SPIF))
                        cpu_relax();
                while (!(read_STAT(drv_data) & BIT_STAT_RXS))
                        cpu_relax();
@@ -516,15 +508,11 @@ static void u16_cs_chg_duplex(struct dri
 {
        struct chip_data *chip = drv_data->cur_chip;
 
-       /* poll for SPI completion before start */
-       while (!(read_STAT(drv_data) & BIT_STAT_SPIF))
-               cpu_relax();
-
        while (drv_data->tx < drv_data->tx_end) {
                cs_active(drv_data, chip);
 
                write_TDBR(drv_data, (*(u16 *) (drv_data->tx)));
-               while (read_STAT(drv_data) & BIT_STAT_TXS)
+               while (!(read_STAT(drv_data) & BIT_STAT_SPIF))
                        cpu_relax();
                while (!(read_STAT(drv_data) & BIT_STAT_RXS))
                        cpu_relax();

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