diff options
| author |   Martin Sperl <kernel@martin.sperl.org> | 2019-03-30 09:31:04 +0000 |
|---|---|---|
| committer |   Mark Brown <broonie@kernel.org> | 2019-04-03 11:32:13 +0700 |
| commit | ccd978b708b03b18196205b3baee83b5047ee453 (patch) | |
| tree | c7727fffed9b5a58baa4329bf417d433ec663828 /drivers/spi/spi-bcm2835aux.c | |
| parent | spi: bcm2835aux: warn in dmesg that native cs is not really supported (diff) | |
| download | linux-dev-ccd978b708b03b18196205b3baee83b5047ee453.tar.xz linux-dev-ccd978b708b03b18196205b3baee83b5047ee453.zip | |
spi: bcm2835aux: setup gpio-cs to output and correct level during setup
Setup gpio-cs to the correct levels during setup and also make the
gpio definitely an output GPIO.
This is transparently fixing some badly configured DTs in the process
where cs-gpio is set but the gpios are still configured with native cs.
It also makes 100% sure that the initial CS levels are as expected -
especially on systems with devices on a bus with mixed CS_HIGH/CS_LOW
settings.
Fixes: 1ea29b39f4c812ec ("spi: bcm2835aux: add bcm2835 auxiliary spi device...")
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Acked-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi/spi-bcm2835aux.c')
| -rw-r--r-- | drivers/spi/spi-bcm2835aux.c | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/drivers/spi/spi-bcm2835aux.c b/drivers/spi/spi-bcm2835aux.c index a105db371417..99414319001a 100644 --- a/drivers/spi/spi-bcm2835aux.c +++ b/drivers/spi/spi-bcm2835aux.c @@ -403,8 +403,20 @@ static int bcm2835aux_spi_setup(struct spi_device *spi) /* sanity check for native cs */ if (spi->mode & SPI_NO_CS) return 0; - if (gpio_is_valid(spi->cs_gpio)) - return 0; + if (gpio_is_valid(spi->cs_gpio)) { + /* with gpio-cs set the GPIO to the correct level + * and as output (in case the dt has the gpio not configured + * as output but native cs) + */ + ret = gpio_direction_output(spi->cs_gpio, + (spi->mode & SPI_CS_HIGH) ? 0 : 1); + if (ret) + dev_err(&spi->dev, + "could not set gpio %i as output: %i\n", + spi->cs_gpio, ret); + + return ret; + } /* for dt-backwards compatibility: only support native on CS0 * known things not supported with broken native CS: |