[PATCH 10/14] Blackfin SPI driver: Clean up useless wait in bfin SPI driver

From: Bryan Wu
Date: Tue Oct 30 2007 - 05:21:38 EST


From: Sonic Zhang <sonic.zhang@xxxxxxxxxx>

Signed-off-by: Sonic Zhang <sonic.zhang@xxxxxxxxxx>
Signed-off-by: Bryan Wu <bryan.wu@xxxxxxxxxx>
---
drivers/spi/spi_bfin5xx.c | 84 ++++++++++++++++++++++++++++-----------------
1 files changed, 52 insertions(+), 32 deletions(-)

diff --git a/drivers/spi/spi_bfin5xx.c b/drivers/spi/spi_bfin5xx.c
index e1fd197..d69719b 100644
--- a/drivers/spi/spi_bfin5xx.c
+++ b/drivers/spi/spi_bfin5xx.c
@@ -276,22 +276,26 @@ static void u8_writer(struct driver_data *drv_data)
dev_dbg(&drv_data->pdev->dev,
"cr8-s is 0x%x\n", read_STAT());

+ /* poll for SPI completion before start */
+ while (!(read_STAT() & BIT_STAT_SPIF))
+ continue;
+
while (drv_data->tx < drv_data->tx_end) {
write_TDBR(*(u8 *) (drv_data->tx));
while (read_STAT() & BIT_STAT_TXS)
continue;
++drv_data->tx;
}
-
- /* poll for SPI completion before returning */
- while (!(read_STAT() & BIT_STAT_SPIF))
- continue;
}

static void u8_cs_chg_writer(struct driver_data *drv_data)
{
struct chip_data *chip = drv_data->cur_chip;

+ /* poll for SPI completion before start */
+ while (!(read_STAT() & BIT_STAT_SPIF))
+ continue;
+
while (drv_data->tx < drv_data->tx_end) {
cs_active(chip);

@@ -304,10 +308,6 @@ static void u8_cs_chg_writer(struct driver_data *drv_data)
udelay(chip->cs_chg_udelay);
++drv_data->tx;
}
-
- /* poll for SPI completion before returning */
- while (!(read_STAT() & BIT_STAT_SPIF))
- continue;
}

static void u8_reader(struct driver_data *drv_data)
@@ -315,6 +315,10 @@ static void u8_reader(struct driver_data *drv_data)
dev_dbg(&drv_data->pdev->dev,
"cr-8 is 0x%x\n", read_STAT());

+ /* poll for SPI completion before start */
+ while (!(read_STAT() & BIT_STAT_SPIF))
+ continue;
+
/* clear TDBR buffer before read(else it will be shifted out) */
write_TDBR(0xFFFF);

@@ -337,6 +341,10 @@ static void u8_cs_chg_reader(struct driver_data *drv_data)
{
struct chip_data *chip = drv_data->cur_chip;

+ /* poll for SPI completion before start */
+ while (!(read_STAT() & BIT_STAT_SPIF))
+ continue;
+
/* clear TDBR buffer before read(else it will be shifted out) */
write_TDBR(0xFFFF);

@@ -365,6 +373,10 @@ static void u8_cs_chg_reader(struct driver_data *drv_data)

static void u8_duplex(struct driver_data *drv_data)
{
+ /* poll for SPI completion before start */
+ while (!(read_STAT() & BIT_STAT_SPIF))
+ continue;
+
/* in duplex mode, clk is triggered by writing of TDBR */
while (drv_data->rx < drv_data->rx_end) {
write_TDBR(*(u8 *) (drv_data->tx));
@@ -376,16 +388,16 @@ static void u8_duplex(struct driver_data *drv_data)
++drv_data->rx;
++drv_data->tx;
}
-
- /* poll for SPI completion before returning */
- while (!(read_STAT() & BIT_STAT_SPIF))
- continue;
}

static void u8_cs_chg_duplex(struct driver_data *drv_data)
{
struct chip_data *chip = drv_data->cur_chip;

+ /* poll for SPI completion before start */
+ while (!(read_STAT() & BIT_STAT_SPIF))
+ continue;
+
while (drv_data->rx < drv_data->rx_end) {
cs_active(chip);

@@ -402,10 +414,6 @@ static void u8_cs_chg_duplex(struct driver_data *drv_data)
++drv_data->rx;
++drv_data->tx;
}
-
- /* poll for SPI completion before returning */
- while (!(read_STAT() & BIT_STAT_SPIF))
- continue;
}

static void u16_writer(struct driver_data *drv_data)
@@ -413,22 +421,26 @@ static void u16_writer(struct driver_data *drv_data)
dev_dbg(&drv_data->pdev->dev,
"cr16 is 0x%x\n", read_STAT());

+ /* poll for SPI completion before start */
+ while (!(read_STAT() & BIT_STAT_SPIF))
+ continue;
+
while (drv_data->tx < drv_data->tx_end) {
write_TDBR(*(u16 *) (drv_data->tx));
while ((read_STAT() & BIT_STAT_TXS))
continue;
drv_data->tx += 2;
}
-
- /* poll for SPI completion before returning */
- while (!(read_STAT() & BIT_STAT_SPIF))
- continue;
}

static void u16_cs_chg_writer(struct driver_data *drv_data)
{
struct chip_data *chip = drv_data->cur_chip;

+ /* poll for SPI completion before start */
+ while (!(read_STAT() & BIT_STAT_SPIF))
+ continue;
+
while (drv_data->tx < drv_data->tx_end) {
cs_active(chip);

@@ -441,10 +453,6 @@ static void u16_cs_chg_writer(struct driver_data *drv_data)
udelay(chip->cs_chg_udelay);
drv_data->tx += 2;
}
-
- /* poll for SPI completion before returning */
- while (!(read_STAT() & BIT_STAT_SPIF))
- continue;
}

static void u16_reader(struct driver_data *drv_data)
@@ -452,6 +460,10 @@ static void u16_reader(struct driver_data *drv_data)
dev_dbg(&drv_data->pdev->dev,
"cr-16 is 0x%x\n", read_STAT());

+ /* poll for SPI completion before start */
+ while (!(read_STAT() & BIT_STAT_SPIF))
+ continue;
+
/* clear TDBR buffer before read(else it will be shifted out) */
write_TDBR(0xFFFF);

@@ -474,6 +486,10 @@ static void u16_cs_chg_reader(struct driver_data *drv_data)
{
struct chip_data *chip = drv_data->cur_chip;

+ /* poll for SPI completion before start */
+ while (!(read_STAT() & BIT_STAT_SPIF))
+ continue;
+
/* clear TDBR buffer before read(else it will be shifted out) */
write_TDBR(0xFFFF);

@@ -502,6 +518,10 @@ static void u16_cs_chg_reader(struct driver_data *drv_data)

static void u16_duplex(struct driver_data *drv_data)
{
+ /* poll for SPI completion before start */
+ while (!(read_STAT() & BIT_STAT_SPIF))
+ continue;
+
/* in duplex mode, clk is triggered by writing of TDBR */
while (drv_data->tx < drv_data->tx_end) {
write_TDBR(*(u16 *) (drv_data->tx));
@@ -513,16 +533,16 @@ static void u16_duplex(struct driver_data *drv_data)
drv_data->rx += 2;
drv_data->tx += 2;
}
-
- /* poll for SPI completion before returning */
- while (!(read_STAT() & BIT_STAT_SPIF))
- continue;
}

static void u16_cs_chg_duplex(struct driver_data *drv_data)
{
struct chip_data *chip = drv_data->cur_chip;

+ /* poll for SPI completion before start */
+ while (!(read_STAT() & BIT_STAT_SPIF))
+ continue;
+
while (drv_data->tx < drv_data->tx_end) {
cs_active(chip);

@@ -539,10 +559,6 @@ static void u16_cs_chg_duplex(struct driver_data *drv_data)
drv_data->rx += 2;
drv_data->tx += 2;
}
-
- /* poll for SPI completion before returning */
- while (!(read_STAT() & BIT_STAT_SPIF))
- continue;
}

/* test if ther is more transfer to be done */
@@ -765,6 +781,10 @@ static void pump_transfers(unsigned long data)
dma_width = WDSIZE_8;
}

+ /* poll for SPI completion before start */
+ while (!(read_STAT() & BIT_STAT_SPIF))
+ continue;
+
/* dirty hack for autobuffer DMA mode */
if (drv_data->tx_dma == 0xFFFF) {
dev_dbg(&drv_data->pdev->dev,
--
1.5.3.4
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/