[PATCH] spi: Fix SPI_CS_HIGH setting when using native and GPIO CS

From: Gregory CLEMENT
Date: Fri Oct 18 2019 - 11:29:29 EST


When improving the CS GPIO support at core level, the SPI_CS_HIGH
has been enabled for all the CS lines used for a given SPI controller.

However, the SPI framework allows to have on the same controller native
CS and GPIO CS. The native CS may not support the SPI_CS_HIGH, so they
should not be setup automatically.

With this patch the setting is done only for the CS that will use a
GPIO as CS

Fixes: f3186dd87669 ("spi: Optionally use GPIO descriptors for CS GPIOs")
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20191018152929.3287-1-gregory.clement@xxxxxxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
drivers/spi/spi.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index f8b4654a57d3..d07517151340 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1711,15 +1711,7 @@ static int of_spi_parse_dt(struct spi_controller *ctlr, struct spi_device *spi,
spi->mode |= SPI_3WIRE;
if (of_property_read_bool(nc, "spi-lsb-first"))
spi->mode |= SPI_LSB_FIRST;
-
- /*
- * For descriptors associated with the device, polarity inversion is
- * handled in the gpiolib, so all chip selects are "active high" in
- * the logical sense, the gpiolib will invert the line if need be.
- */
- if (ctlr->use_gpio_descriptors)
- spi->mode |= SPI_CS_HIGH;
- else if (of_property_read_bool(nc, "spi-cs-high"))
+ if (of_property_read_bool(nc, "spi-cs-high"))
spi->mode |= SPI_CS_HIGH;

/* Device DUAL/QUAD mode */
@@ -1783,6 +1775,14 @@ static int of_spi_parse_dt(struct spi_controller *ctlr, struct spi_device *spi,
}
spi->chip_select = value;

+ /*
+ * For descriptors associated with the device, polarity inversion is
+ * handled in the gpiolib, so all gpio chip selects are "active high"
+ * in the logical sense, the gpiolib will invert the line if need be.
+ */
+ if ((ctlr->use_gpio_descriptors) && ctlr->cs_gpiods[spi->chip_select])
+ spi->mode |= SPI_CS_HIGH;
+
/* Device speed */
rc = of_property_read_u32(nc, "spi-max-frequency", &value);
if (rc) {
--
2.20.1