From 10a6aa963c1542724d9ca370386be6164914fc76 Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Fri, 18 Sep 2020 16:26:06 +0200 Subject: spi: mpc8xxx_spi.c: fix cs activate/deactivate Somewhere between v2020.04 and v2020.07 the mpc8xxx_spi driver broke, I'm guessing due to this hunk @@ -559,6 +560,8 @@ int dm_gpio_set_dir_flags(struct gpio_desc *desc, ulong flags) if (ret) return ret; + /* combine the requested flags (for IN/OUT) and the descriptor flags */ + flags |= desc->flags; ret = _dm_gpio_set_dir_flags(desc, flags); from commit 695e5fd5469a ("gpio: update dir_flags management"). But the blame is mostly on the driver itself which seems rather confused: The chip select gpios are requested with GPIOD_ACTIVE_LOW, but then in each activate/deactivate, dm_gpio_set_dir_flags() is called with merely GPIOD_IS_OUT, and then the driver call set_value(0) for activate. That used to work, but with the above hunk, the ACTIVE_LOW setting from the request becomes persistent, so the gpio driver ends up being asked to set the value to 1 in mpc8xxx_spi_cs_activate(). So drop the dm_gpio_set_dir_flags() calls in the activate/deactivate functions, and use a value of 1 to mean "logically enabled". Ideally, I think we should also drop the GPIOD_ACTIVE_LOW from the request and make it up to the list of gpio cs in DT to indicate whether that CS is enabled when driven low (as is of course usually the case), but that requires changing arch/powerpc/dts/gdsys/gazerbeam-base.dtsi among others, and I don't have that hardware to test on. I have, however, tested our own (mpc8309-based) hardware with this change, and I have also tested that removing the GPIOD_ACTIVE_LOW from the request and updating our DT as - gpios = <&spisel 0 0>; + gpios = <&spisel 0 GPIO_ACTIVE_LOW>; still works. Signed-off-by: Rasmus Villemoes --- drivers/spi/mpc8xxx_spi.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/spi/mpc8xxx_spi.c b/drivers/spi/mpc8xxx_spi.c index 811b5d44fb..ec39c12b3d 100644 --- a/drivers/spi/mpc8xxx_spi.c +++ b/drivers/spi/mpc8xxx_spi.c @@ -109,8 +109,7 @@ static void mpc8xxx_spi_cs_activate(struct udevice *dev) struct mpc8xxx_priv *priv = dev_get_priv(dev->parent); struct dm_spi_slave_platdata *platdata = dev_get_parent_platdata(dev); - dm_gpio_set_dir_flags(&priv->gpios[platdata->cs], GPIOD_IS_OUT); - dm_gpio_set_value(&priv->gpios[platdata->cs], 0); + dm_gpio_set_value(&priv->gpios[platdata->cs], 1); } static void mpc8xxx_spi_cs_deactivate(struct udevice *dev) @@ -118,8 +117,7 @@ static void mpc8xxx_spi_cs_deactivate(struct udevice *dev) struct mpc8xxx_priv *priv = dev_get_priv(dev->parent); struct dm_spi_slave_platdata *platdata = dev_get_parent_platdata(dev); - dm_gpio_set_dir_flags(&priv->gpios[platdata->cs], GPIOD_IS_OUT); - dm_gpio_set_value(&priv->gpios[platdata->cs], 1); + dm_gpio_set_value(&priv->gpios[platdata->cs], 0); } static int mpc8xxx_spi_xfer(struct udevice *dev, uint bitlen, -- cgit