This is a note to let you know that I've just added the patch titled
gpio: sifive: use the correct register to read output values
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
gpio-sifive-use-the-correct-register-to-read-output-.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 3057d4929183f2ea7867d975e3c3ea3aa16b4c76
Author: Niklas Cassel <niklas.cassel@xxxxxxx>
Date: Fri Feb 4 13:02:25 2022 +0000
gpio: sifive: use the correct register to read output values
[ Upstream commit cc38ef936840ac29204d806deb4d1836ec509594 ]
Setting the output of a GPIO to 1 using gpiod_set_value(), followed by
reading the same GPIO using gpiod_get_value(), will currently yield an
incorrect result.
This is because the SiFive GPIO device stores the output values in reg_set,
not reg_dat.
Supply the flag BGPIOF_READ_OUTPUT_REG_SET to bgpio_init() so that the
generic driver reads the correct register.
Fixes: 96868dce644d ("gpio/sifive: Add GPIO driver for SiFive SoCs")
Signed-off-by: Niklas Cassel <niklas.cassel@xxxxxxx>
Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
[Bartosz: added the Fixes tag]
Signed-off-by: Bartosz Golaszewski <brgl@xxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/gpio/gpio-sifive.c b/drivers/gpio/gpio-sifive.c
index d5eb9ca119016..4f28fa73450c1 100644
--- a/drivers/gpio/gpio-sifive.c
+++ b/drivers/gpio/gpio-sifive.c
@@ -206,7 +206,7 @@ static int sifive_gpio_probe(struct platform_device *pdev)
NULL,
chip->base + SIFIVE_GPIO_OUTPUT_EN,
chip->base + SIFIVE_GPIO_INPUT_EN,
- 0);
+ BGPIOF_READ_OUTPUT_REG_SET);
if (ret) {
dev_err(dev, "unable to init generic GPIO\n");
return ret;
