diff options
Diffstat (limited to 'target/linux/bcm27xx/patches-5.15/950-0534-gpio-bcm-virt-Fix-the-get-method.patch')
| -rw-r--r-- | target/linux/bcm27xx/patches-5.15/950-0534-gpio-bcm-virt-Fix-the-get-method.patch | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/target/linux/bcm27xx/patches-5.15/950-0534-gpio-bcm-virt-Fix-the-get-method.patch b/target/linux/bcm27xx/patches-5.15/950-0534-gpio-bcm-virt-Fix-the-get-method.patch new file mode 100644 index 0000000000..9c12ff483a --- /dev/null +++ b/target/linux/bcm27xx/patches-5.15/950-0534-gpio-bcm-virt-Fix-the-get-method.patch @@ -0,0 +1,29 @@ +From 6e6d30ab723843fea8d9df368b35e89327f33c11 Mon Sep 17 00:00:00 2001 +From: Phil Elwell <phil@raspberrypi.com> +Date: Tue, 19 Oct 2021 11:23:43 +0100 +Subject: [PATCH] gpio: bcm-virt: Fix the get() method + +The get() method does not understand the on-the-wire encoding of the +remote GPIO states, thinking they are simple on/off bits when they are +really pairs of 16-bit counts. Rewrite the get() handler to return the +value last written, which will eventually match the actual GPIO state +if there are no other changes. + +See: https://github.com/raspberrypi/linux/issues/4638 + +Signed-off-by: Phil Elwell <phil@raspberrypi.com> +--- + drivers/gpio/gpio-bcm-virt.c | 2 +- + 1 file changed, 1 insertion(+), 1 deletion(-) + +--- a/drivers/gpio/gpio-bcm-virt.c ++++ b/drivers/gpio/gpio-bcm-virt.c +@@ -49,7 +49,7 @@ static int brcmvirt_gpio_get(struct gpio + unsigned v; + gpio = container_of(gc, struct brcmvirt_gpio, gc); + v = readl(gpio->ts_base + off); +- return (v >> off) & 1; ++ return (s16)((v >> 16) - v) > 0; + } + + static void brcmvirt_gpio_set(struct gpio_chip *gc, unsigned off, int val) |