diff options
Diffstat (limited to 'drivers/spi/spi-bcm2835.c')
-rw-r--r-- | drivers/spi/spi-bcm2835.c | 28 |
1 files changed, 23 insertions, 5 deletions
diff --git a/drivers/spi/spi-bcm2835.c b/drivers/spi/spi-bcm2835.c index 59705ab23577..c9357bb393d3 100644 --- a/drivers/spi/spi-bcm2835.c +++ b/drivers/spi/spi-bcm2835.c @@ -553,13 +553,11 @@ 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 @@ -592,6 +590,25 @@ 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) { @@ -739,6 +756,7 @@ 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); |