[PATCH] spi: bcm2835: fix gpio cs level inversion

Martin Hundebøll martin at geanix.com
Wed Oct 14 05:02:30 EDT 2020


The work on improving gpio chip-select in spi core, and the following
fixes, has caused the bcm2835 spi driver to use wrong levels. Fix this
by simply removing level handling in the bcm2835 driver, and let the
core do its work.

Fixes: 3e5ec1db8bfe ("spi: Fix SPI_CS_HIGH setting when using native and GPIO CS")
Cc: <stable at vger.kernel.org>
Signed-off-by: Martin Hundebøll <martin at geanix.com>
---
 drivers/spi/spi-bcm2835.c | 12 ------------
 1 file changed, 12 deletions(-)

diff --git a/drivers/spi/spi-bcm2835.c b/drivers/spi/spi-bcm2835.c
index b87116e9b413..9b6ba94fe878 100644
--- a/drivers/spi/spi-bcm2835.c
+++ b/drivers/spi/spi-bcm2835.c
@@ -1259,18 +1259,6 @@ static int bcm2835_spi_setup(struct spi_device *spi)
 	if (!chip)
 		return 0;
 
-	/*
-	 * Retrieve the corresponding GPIO line used for CS.
-	 * The inversion semantics will be handled by the GPIO core
-	 * code, so we pass GPIOD_OUT_LOW for "unasserted" and
-	 * the correct flag for inversion semantics. The SPI_CS_HIGH
-	 * on spi->mode cannot be checked for polarity in this case
-	 * as the flag use_gpio_descriptors enforces SPI_CS_HIGH.
-	 */
-	if (of_property_read_bool(spi->dev.of_node, "spi-cs-high"))
-		lflags = GPIO_ACTIVE_HIGH;
-	else
-		lflags = GPIO_ACTIVE_LOW;
 	spi->cs_gpiod = gpiochip_request_own_desc(chip, 8 - spi->chip_select,
 						  DRV_NAME,
 						  lflags,
-- 
2.28.0




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