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Diffstat (limited to 'target/linux/brcm2708/patches-4.19/950-0122-gpiolib-Don-t-prevent-IRQ-usage-of-output-GPIOs.patch')
-rw-r--r--target/linux/brcm2708/patches-4.19/950-0122-gpiolib-Don-t-prevent-IRQ-usage-of-output-GPIOs.patch46
1 files changed, 46 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-4.19/950-0122-gpiolib-Don-t-prevent-IRQ-usage-of-output-GPIOs.patch b/target/linux/brcm2708/patches-4.19/950-0122-gpiolib-Don-t-prevent-IRQ-usage-of-output-GPIOs.patch
new file mode 100644
index 0000000000..17867c330a
--- /dev/null
+++ b/target/linux/brcm2708/patches-4.19/950-0122-gpiolib-Don-t-prevent-IRQ-usage-of-output-GPIOs.patch
@@ -0,0 +1,46 @@
+From 1929780cf2cc997f990085bd878112b28f4175c9 Mon Sep 17 00:00:00 2001
+From: Phil Elwell <phil@raspberrypi.org>
+Date: Tue, 24 Apr 2018 14:42:27 +0100
+Subject: [PATCH] gpiolib: Don't prevent IRQ usage of output GPIOs
+
+Upstream Linux deems using output GPIOs to generate IRQs as a bogus
+use case, even though the BCM2835 GPIO controller is capable of doing
+so. A number of users would like to make use of this facility, so
+disable the checks.
+
+See: https://github.com/raspberrypi/linux/issues/2527
+
+Signed-off-by: Phil Elwell <phil@raspberrypi.org>
+---
+ drivers/gpio/gpiolib.c | 6 ++++--
+ 1 file changed, 4 insertions(+), 2 deletions(-)
+
+--- a/drivers/gpio/gpiolib.c
++++ b/drivers/gpio/gpiolib.c
+@@ -53,6 +53,8 @@
+ #define extra_checks 0
+ #endif
+
++#define dont_test_bit(b,d) (0)
++
+ /* Device and char device-related information */
+ static DEFINE_IDA(gpio_ida);
+ static dev_t gpio_devt;
+@@ -2654,7 +2656,7 @@ int gpiod_direction_output(struct gpio_d
+ value = !!value;
+
+ /* GPIOs used for IRQs shall not be set as output */
+- if (test_bit(FLAG_USED_AS_IRQ, &desc->flags)) {
++ if (dont_test_bit(FLAG_USED_AS_IRQ, &desc->flags)) {
+ gpiod_err(desc,
+ "%s: tried to set a GPIO tied to an IRQ as output\n",
+ __func__);
+@@ -3353,7 +3355,7 @@ int gpiochip_lock_as_irq(struct gpio_chi
+ }
+ }
+
+- if (test_bit(FLAG_IS_OUT, &desc->flags)) {
++ if (dont_test_bit(FLAG_IS_OUT, &desc->flags)) {
+ chip_err(chip,
+ "%s: tried to flag a GPIO set as output for IRQ\n",
+ __func__);