A write to the TX buffer is performed before entering the loop to "avoid clock starvation". This sometimes results in subsequent writes in davinci_spi_xfer_data() to occur while the TXFULL bit is asserted, leading to write failures.

Remove the preload of the TX buffer.

Signed-off-by: Bastien Curutchet bastien.curutchet@bootlin.com --- Hi all,

I've ran into write failures to flash on my platform based on the DAVINCI/OMAP L138. This patch fixes it.

drivers/spi/davinci_spi.c | 9 --------- 1 file changed, 9 deletions(-)

diff --git a/drivers/spi/davinci_spi.c b/drivers/spi/davinci_spi.c index 25f5e9fdeb..07c46b8b66 100644 --- a/drivers/spi/davinci_spi.c +++ b/drivers/spi/davinci_spi.c @@ -129,9 +129,6 @@ static int davinci_spi_read(struct davinci_spi_slave *ds, unsigned int len, while (readl(&ds->regs->buf) & SPIBUF_TXFULL_MASK) ;

- /* preload the TX buffer to avoid clock starvation */ - writel(data1_reg_val, &ds->regs->dat1); - /* keep reading 1 byte until only 1 byte left */ while ((len--) > 1) *rxp++ = davinci_spi_xfer_data(ds, data1_reg_val); @@ -159,12 +156,6 @@ static int davinci_spi_write(struct davinci_spi_slave *ds, unsigned int len, while (readl(&ds->regs->buf) & SPIBUF_TXFULL_MASK) ;

- /* preload the TX buffer to avoid clock starvation */ - if (len > 2) { - writel(data1_reg_val | *txp++, &ds->regs->dat1); - len--; - } - /* keep writing 1 byte until only 1 byte left */ while ((len--) > 1) davinci_spi_xfer_data(ds, data1_reg_val | *txp++);