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Diffstat (limited to 'kernel/drivers/spi/spi-bcm2835.c')
-rw-r--r--kernel/drivers/spi/spi-bcm2835.c28
1 files changed, 23 insertions, 5 deletions
diff --git a/kernel/drivers/spi/spi-bcm2835.c b/kernel/drivers/spi/spi-bcm2835.c
index 37875cf94..a5067739e 100644
--- a/kernel/drivers/spi/spi-bcm2835.c
+++ b/kernel/drivers/spi/spi-bcm2835.c
@@ -257,13 +257,11 @@ static int bcm2835_spi_transfer_one(struct spi_master *master,
spi_used_hz = cdiv ? (clk_hz / cdiv) : (clk_hz / 65536);
bcm2835_wr(bs, BCM2835_SPI_CLK, cdiv);
- /* handle all the modes */
+ /* handle all the 3-wire mode */
if ((spi->mode & SPI_3WIRE) && (tfr->rx_buf))
cs |= BCM2835_SPI_CS_REN;
- if (spi->mode & SPI_CPOL)
- cs |= BCM2835_SPI_CS_CPOL;
- if (spi->mode & SPI_CPHA)
- cs |= BCM2835_SPI_CS_CPHA;
+ else
+ cs &= ~BCM2835_SPI_CS_REN;
/* for gpio_cs set dummy CS so that no HW-CS get changed
* we can not run this in bcm2835_spi_set_cs, as it does
@@ -291,6 +289,25 @@ static int bcm2835_spi_transfer_one(struct spi_master *master,
return bcm2835_spi_transfer_one_irq(master, spi, tfr, cs);
}
+static int bcm2835_spi_prepare_message(struct spi_master *master,
+ struct spi_message *msg)
+{
+ struct spi_device *spi = msg->spi;
+ struct bcm2835_spi *bs = spi_master_get_devdata(master);
+ u32 cs = bcm2835_rd(bs, BCM2835_SPI_CS);
+
+ cs &= ~(BCM2835_SPI_CS_CPOL | BCM2835_SPI_CS_CPHA);
+
+ if (spi->mode & SPI_CPOL)
+ cs |= BCM2835_SPI_CS_CPOL;
+ if (spi->mode & SPI_CPHA)
+ cs |= BCM2835_SPI_CS_CPHA;
+
+ bcm2835_wr(bs, BCM2835_SPI_CS, cs);
+
+ return 0;
+}
+
static void bcm2835_spi_handle_err(struct spi_master *master,
struct spi_message *msg)
{
@@ -429,6 +446,7 @@ static int bcm2835_spi_probe(struct platform_device *pdev)
master->set_cs = bcm2835_spi_set_cs;
master->transfer_one = bcm2835_spi_transfer_one;
master->handle_err = bcm2835_spi_handle_err;
+ master->prepare_message = bcm2835_spi_prepare_message;
master->dev.of_node = pdev->dev.of_node;
bs = spi_master_get_devdata(master);