From ada9e3fcc175db4538f5b5e05abf5dedf626e550 Mon Sep 17 00:00:00 2001 From: Charles Keepax Date: Wed, 27 Nov 2019 15:39:36 +0000 Subject: [PATCH] spi: dw: Correct handling of native chipselect This patch reverts commit 6e0a32d6f376 ("spi: dw: Fix default polarity of native chipselect"). The SPI framework always called the set_cs callback with the logic level it desired on the chip select line, which is what the drivers original handling supported. commit f3186dd87669 ("spi: Optionally use GPIO descriptors for CS GPIOs") changed these symantics, but only in the case of drivers that also support GPIO chip selects, to true meaning apply slave select rather than logic high. This left things in an odd state where a driver that only supports hardware chip selects, the core would handle polarity but if the driver supported GPIOs as well the driver should handle polarity. At this point the reverted change was applied to change the logic in the driver to match new system. This was then broken by commit 3e5ec1db8bfe ("spi: Fix SPI_CS_HIGH setting when using native and GPIO CS") which reverted the core back to consistently calling set_cs with a logic level. This fix reverts the driver code back to its original state to match the current core code. This is probably a better fix as a) the set_cs callback is always called with consistent symantics and b) the inversion for SPI_CS_HIGH can be handled in the core and doesn't need to be coded in each driver supporting it. Fixes: 3e5ec1db8bfe ("spi: Fix SPI_CS_HIGH setting when using native and GPIO CS") Signed-off-by: Charles Keepax Acked-by: Linus Walleij Link: https://lore.kernel.org/r/20191127153936.29719-1-ckeepax@opensource.cirrus.com Signed-off-by: Mark Brown --- drivers/spi/spi-dw.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c index 466f5c67843b..9387f60eb496 100644 --- a/drivers/spi/spi-dw.c +++ b/drivers/spi/spi-dw.c @@ -129,10 +129,11 @@ void dw_spi_set_cs(struct spi_device *spi, bool enable) struct dw_spi *dws = spi_controller_get_devdata(spi->controller); struct chip_data *chip = spi_get_ctldata(spi); + /* Chip select logic is inverted from spi_set_cs() */ if (chip && chip->cs_control) - chip->cs_control(enable); + chip->cs_control(!enable); - if (enable) + if (!enable) dw_writel(dws, DW_SPI_SER, BIT(spi->chip_select)); else if (dws->cs_override) dw_writel(dws, DW_SPI_SER, 0);