From: Kalle Valo Date: Thu, 24 Jan 2008 22:00:40 +0000 (-0800) Subject: spi: omap2_mcspi PIO RX fix X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=feed9bab7b14b77be8d796bcee95e2343fb82955;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git spi: omap2_mcspi PIO RX fix Before transmission of the last word in PIO RX_ONLY mode rx+tx mode is enabled: /* prevent last RX_ONLY read from triggering * more word i/o: switch to rx+tx */ if (c == 0 && tx == NULL) mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, l); But because c is decremented after the test, c will never be zero and rx+tx will not be enabled. This breaks RX_ONLY mode PIO transfers. Fix it by decrementing c in the beginning of the various I/O loops. Signed-off-by: Kalle Valo Signed-off-by: David Brownell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/drivers/spi/omap2_mcspi.c b/drivers/spi/omap2_mcspi.c index 3cdab131c4a9..ea61724ae225 100644 --- a/drivers/spi/omap2_mcspi.c +++ b/drivers/spi/omap2_mcspi.c @@ -350,6 +350,7 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) tx = xfer->tx_buf; do { + c -= 1; if (tx != NULL) { if (mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_TXS) < 0) { @@ -380,7 +381,6 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) word_len, *(rx - 1)); #endif } - c -= 1; } while (c); } else if (word_len <= 16) { u16 *rx; @@ -389,6 +389,7 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) rx = xfer->rx_buf; tx = xfer->tx_buf; do { + c -= 2; if (tx != NULL) { if (mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_TXS) < 0) { @@ -419,7 +420,6 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) word_len, *(rx - 1)); #endif } - c -= 2; } while (c); } else if (word_len <= 32) { u32 *rx; @@ -428,6 +428,7 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) rx = xfer->rx_buf; tx = xfer->tx_buf; do { + c -= 4; if (tx != NULL) { if (mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_TXS) < 0) { @@ -458,7 +459,6 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) word_len, *(rx - 1)); #endif } - c -= 4; } while (c); }