Some GPIO lines have stopped working after the patch commit 2ab73c6d8323f ("gpio: Support GPIO controllers without pin-ranges")
And this has supposedly been fixed in the following patches commit 89ad556b7f96a ("gpio: Avoid using pin ranges with !PINCTRL") commit 6dbbf84603961 ("gpiolib: Don't free if pin ranges are not defined")
But an erratic behavior where some GPIO lines work while others do not work has been introduced.
This patch reverts those changes so that the sysfs-gpio interface works properly again.
Signed-off-by: Marcelo Roberto Jimenez marcelo.jimenez@gmail.com ---
Hi,
My system is ARM926EJ-S rev 5 (v5l) (AT91SAM9G25), the board is an ACME Systems Arietta.
The system used sysfs-gpio to manage a few gpio lines, and I have noticed that some have stopped working.
The test script is very simple:
#! /bin/bash
cd /sys/class/gpio/ echo 24 > export
cd pioA24 echo out > direction
echo 0 > value cat value echo 1 > value cat value echo 0 > value cat value echo 1 > value cat value
cd .. echo 24 > unexport
In a "good" kernel, this script outputs 0, 1, 0, 1. In a bad kernel, the output result is 1, 1, 1, 1. Also it must be possible to run this script twice without errors, that was the issue with the gpiochip_generic_free() call that had been addressed in another patch.
In my system PINCTRL is automatically selected by SOC_AT91SAM9 [=y] && ARCH_AT91 [=y] && ARCH_MULTI_V5 [=y]
So it is not an option to disable it to make it work.
Best regards, Marcelo.
drivers/gpio/gpiolib.c | 10 ---------- 1 file changed, 10 deletions(-)
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index af5bb8fedfea..ac69ec8fb37a 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -1804,11 +1804,6 @@ static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc) */ int gpiochip_generic_request(struct gpio_chip *gc, unsigned offset) { -#ifdef CONFIG_PINCTRL - if (list_empty(&gc->gpiodev->pin_ranges)) - return 0; -#endif - return pinctrl_gpio_request(gc->gpiodev->base + offset); } EXPORT_SYMBOL_GPL(gpiochip_generic_request); @@ -1820,11 +1815,6 @@ EXPORT_SYMBOL_GPL(gpiochip_generic_request); */ void gpiochip_generic_free(struct gpio_chip *gc, unsigned offset) { -#ifdef CONFIG_PINCTRL - if (list_empty(&gc->gpiodev->pin_ranges)) - return; -#endif - pinctrl_gpio_free(gc->gpiodev->base + offset); } EXPORT_SYMBOL_GPL(gpiochip_generic_free);