diff options
| author | Maxime Chevallier <maxime.chevallier@smile.fr> | 2017-10-10 10:43:18 +0200 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2017-10-10 10:17:06 +0100 |
| commit | dd7aa8d4b53b3484ba31ba56f3ff1be7deb38530 (patch) | |
| tree | ac3480bb36c82d2319bb4820a5b02c9d226521ba /drivers/spi | |
| parent | 5a866ec0014b2baa4ecbb1eaa19c835482829d08 (diff) | |
| download | linux-dd7aa8d4b53b3484ba31ba56f3ff1be7deb38530.tar.bz2 | |
spi: a3700: Change SPI mode before asserting chip-select
The spi device mode should be configured in the controller before the
chip-select is asserted, so that a clock polarity configuration change
is not interpreted as a clock tick by the device.
This patch moves the mode setting to the 'prepare_message' function
instead of the 'transfer_one' function.
By doing so, this patch also removes redundant code in
a3700_spi_clock_set.
This was tested on EspressoBin board, with spidev.
Signed-off-by: Maxime Chevallier <maxime.chevallier@smile.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi-armada-3700.c | 17 |
1 files changed, 4 insertions, 13 deletions
diff --git a/drivers/spi/spi-armada-3700.c b/drivers/spi/spi-armada-3700.c index 568e1c65aa82..77fe55ce790c 100644 --- a/drivers/spi/spi-armada-3700.c +++ b/drivers/spi/spi-armada-3700.c @@ -213,7 +213,7 @@ static void a3700_spi_mode_set(struct a3700_spi *a3700_spi, } static void a3700_spi_clock_set(struct a3700_spi *a3700_spi, - unsigned int speed_hz, u16 mode) + unsigned int speed_hz) { u32 val; u32 prescale; @@ -231,17 +231,6 @@ static void a3700_spi_clock_set(struct a3700_spi *a3700_spi, val |= A3700_SPI_CLK_CAPT_EDGE; spireg_write(a3700_spi, A3700_SPI_IF_TIME_REG, val); } - - val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG); - val &= ~(A3700_SPI_CLK_POL | A3700_SPI_CLK_PHA); - - if (mode & SPI_CPOL) - val |= A3700_SPI_CLK_POL; - - if (mode & SPI_CPHA) - val |= A3700_SPI_CLK_PHA; - - spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val); } static void a3700_spi_bytelen_set(struct a3700_spi *a3700_spi, unsigned int len) @@ -423,7 +412,7 @@ static void a3700_spi_transfer_setup(struct spi_device *spi, a3700_spi = spi_master_get_devdata(spi->master); - a3700_spi_clock_set(a3700_spi, xfer->speed_hz, spi->mode); + a3700_spi_clock_set(a3700_spi, xfer->speed_hz); byte_len = xfer->bits_per_word >> 3; @@ -584,6 +573,8 @@ static int a3700_spi_prepare_message(struct spi_master *master, a3700_spi_bytelen_set(a3700_spi, 4); + a3700_spi_mode_set(a3700_spi, spi->mode); + return 0; } |