redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

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: 1ea29b39f4 ("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>
hifive-unleashed-5.2
Martin Sperl 2019-03-30 09:31:04 +00:00 committed by Mark Brown
parent 519f2c22a6
commit ccd978b708
No known key found for this signature in database
GPG Key ID: 24D68B725D5487D0
1 changed files with 14 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
drivers/spi/spi-bcm2835aux.c
View File

@ -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: