| From 122b21149cada59805040895f3d679ceb0e00063 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 | 8 +++++--- |
| 1 file changed, 5 insertions(+), 3 deletions(-) |
| |
| --- a/drivers/gpio/gpiolib.c |
| +++ b/drivers/gpio/gpiolib.c |
| @@ -55,6 +55,8 @@ |
| #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; |
| @@ -3091,8 +3093,8 @@ int gpiod_direction_output(struct gpio_d |
| value = !!value; |
| |
| /* GPIOs used for enabled IRQs shall not be set as output */ |
| - if (test_bit(FLAG_USED_AS_IRQ, &desc->flags) && |
| - test_bit(FLAG_IRQ_IS_ENABLED, &desc->flags)) { |
| + if (dont_test_bit(FLAG_USED_AS_IRQ, &desc->flags) && |
| + dont_test_bit(FLAG_IRQ_IS_ENABLED, &desc->flags)) { |
| gpiod_err(desc, |
| "%s: tried to set a GPIO tied to an IRQ as output\n", |
| __func__); |
| @@ -3895,8 +3897,8 @@ int gpiochip_lock_as_irq(struct gpio_chi |
| } |
| |
| /* To be valid for IRQ the line needs to be input or open drain */ |
| - if (test_bit(FLAG_IS_OUT, &desc->flags) && |
| - !test_bit(FLAG_OPEN_DRAIN, &desc->flags)) { |
| + if (dont_test_bit(FLAG_IS_OUT, &desc->flags) && |
| + !dont_test_bit(FLAG_OPEN_DRAIN, &desc->flags)) { |
| chip_err(chip, |
| "%s: tried to flag a GPIO set as output for IRQ\n", |
| __func__); |