| Message ID | 1430752248-15401-4-git-send-email-johan@kernel.org |
|---|---|
| State | New |
| Headers | show |
On Mon, May 4, 2015 at 5:10 PM, Johan Hovold <johan@kernel.org> wrote: > Drivers should call gpiochip_lock_as_irq (which prevents the pin > direction from being changed) in their irq_request_resources callbacks > but some drivers currently fail to do so. > > Instead a second, explicit and often redundant call to lock-as-irq is > made by the sysfs-interface implementation after an irq has been > requested. > > Move the explicit call before the irq-request to match the unlock done > after the irq is later released. Note that this also fixes an irq leak, > should the explicit call ever have failed. > > Also add a comment about removing the redundant call once the broken > drivers have been fixed. > > Signed-off-by: Johan Hovold <johan@kernel.org> Patch 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/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c index af3bc7a8033b..b2b62cc6f9e1 100644 --- a/drivers/gpio/gpiolib-sysfs.c +++ b/drivers/gpio/gpiolib-sysfs.c @@ -195,20 +195,28 @@ static int gpio_setup_irq(struct gpio_desc *desc, struct device *dev, } } - ret = request_any_context_irq(irq, gpio_sysfs_irq, irq_flags, - "gpiolib", value_sd); + /* + * FIXME: This should be done in the irq_request_resources callback + * when the irq is requested, but a few drivers currently fail + * to do so. + * + * Remove this redundant call (along with the corresponding + * unlock) when those drivers have been fixed. + */ + ret = gpiochip_lock_as_irq(desc->chip, gpio_chip_hwgpio(desc)); if (ret < 0) goto free_id; - ret = gpiochip_lock_as_irq(desc->chip, gpio_chip_hwgpio(desc)); - if (ret < 0) { - gpiod_warn(desc, "failed to flag the GPIO for IRQ\n"); - goto free_id; - } + ret = request_any_context_irq(irq, gpio_sysfs_irq, irq_flags, + "gpiolib", value_sd); + if (ret < 0) + goto err_unlock; desc->flags |= gpio_flags; return 0; +err_unlock: + gpiochip_unlock_as_irq(desc->chip, gpio_chip_hwgpio(desc)); free_id: idr_remove(&dirent_idr, id); desc->flags &= GPIO_FLAGS_MASK;
Drivers should call gpiochip_lock_as_irq (which prevents the pin direction from being changed) in their irq_request_resources callbacks but some drivers currently fail to do so. Instead a second, explicit and often redundant call to lock-as-irq is made by the sysfs-interface implementation after an irq has been requested. Move the explicit call before the irq-request to match the unlock done after the irq is later released. Note that this also fixes an irq leak, should the explicit call ever have failed. Also add a comment about removing the redundant call once the broken drivers have been fixed. Signed-off-by: Johan Hovold <johan@kernel.org> --- drivers/gpio/gpiolib-sysfs.c | 22 +++++++++++++++------- 1 file changed, 15 insertions(+), 7 deletions(-)