| Message ID | 20180216191243.129130-1-djkurtz@chromium.org |
|---|---|
| State | New |
| Headers | show |
| Series | pinctrl/amd: add get_direction handler | expand |
On Fri, Feb 16, 2018 at 8:12 PM, Daniel Kurtz <djkurtz@chromium.org> wrote: > On boot, gpiochip_add_data() initializes the FLAG_IS_OUT bit in > desc->flags iff its gpio_chip does not have ->direction_input() handler, > else it is initialized to 0, which implies the GPIO is an "input". > > Later, the sysfs "direction" handler will use gpiod_get_direction() to > get the current direction, but if no ->get_direction() handler is > installed, the result will just be the current (initial) value of flags, > which will always be OUT irregardless of the initial register value. > > Add a get_direction() handler to pinctrl-amd to fix this and always > provide the correct value for direction. > > Signed-off-by: Daniel Kurtz <djkurtz@chromium.org> Hm, please don't use the sysfs... use the chardev! Anyways, patch is fine and applied. Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe linux-gpio" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/pinctrl/pinctrl-amd.c b/drivers/pinctrl/pinctrl-amd.c index 61d830c2bc17..281b700fe7e9 100644 --- a/drivers/pinctrl/pinctrl-amd.c +++ b/drivers/pinctrl/pinctrl-amd.c @@ -40,6 +40,19 @@ #include "pinctrl-utils.h" #include "pinctrl-amd.h" +static int amd_gpio_get_direction(struct gpio_chip *gc, unsigned offset) +{ + unsigned long flags; + u32 pin_reg; + struct amd_gpio *gpio_dev = gpiochip_get_data(gc); + + raw_spin_lock_irqsave(&gpio_dev->lock, flags); + pin_reg = readl(gpio_dev->base + offset * 4); + raw_spin_unlock_irqrestore(&gpio_dev->lock, flags); + + return !(pin_reg & BIT(OUTPUT_ENABLE_OFF)); +} + static int amd_gpio_direction_input(struct gpio_chip *gc, unsigned offset) { unsigned long flags; @@ -845,6 +858,7 @@ static int amd_gpio_probe(struct platform_device *pdev) #endif gpio_dev->pdev = pdev; + gpio_dev->gc.get_direction = amd_gpio_get_direction; gpio_dev->gc.direction_input = amd_gpio_direction_input; gpio_dev->gc.direction_output = amd_gpio_direction_output; gpio_dev->gc.get = amd_gpio_get_value;
On boot, gpiochip_add_data() initializes the FLAG_IS_OUT bit in desc->flags iff its gpio_chip does not have ->direction_input() handler, else it is initialized to 0, which implies the GPIO is an "input". Later, the sysfs "direction" handler will use gpiod_get_direction() to get the current direction, but if no ->get_direction() handler is installed, the result will just be the current (initial) value of flags, which will always be OUT irregardless of the initial register value. Add a get_direction() handler to pinctrl-amd to fix this and always provide the correct value for direction. Signed-off-by: Daniel Kurtz <djkurtz@chromium.org> --- drivers/pinctrl/pinctrl-amd.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+)