Message ID | 1455542246-16761-1-git-send-email-ldewangan@nvidia.com |
---|---|
State | New |
Headers | show |
On Mon, Feb 15, 2016 at 2:17 PM, Laxman Dewangan <ldewangan@nvidia.com> wrote: > Add device managed APIs devm_gpiochip_add_data() and > devm_gpiochip_remove() for the APIs gpiochip_add_data() > and gpiochip_remove(). > > This helps in reducing code in error path and sometimes > removal of .remove callback for driver unbind. > > Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com> I like the looks of this. One comment: you must also patch Documentation/driver-model/devres.txt Will you also follow up with a massive patch set making use of this new API? I feel bad about merging an API if it's not used. Thanks for only supporting this for the new _data() function. 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
On Tuesday 16 February 2016 08:33 PM, Linus Walleij wrote: > On Mon, Feb 15, 2016 at 2:17 PM, Laxman Dewangan <ldewangan@nvidia.com> wrote: > >> Add device managed APIs devm_gpiochip_add_data() and >> devm_gpiochip_remove() for the APIs gpiochip_add_data() >> and gpiochip_remove(). >> >> This helps in reducing code in error path and sometimes >> removal of .remove callback for driver unbind. >> >> Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com> > I like the looks of this. > > One comment: you must also patch > Documentation/driver-model/devres.txt Sure, > > Will you also follow up with a massive patch set making use of > this new API? I feel bad about merging an API if it's not used. > > Thanks for only supporting this for the new _data() function. > > Yes, I have planned for this to use this new API. This is just for getting review whether fine or not to have devm_* APIs so that I can make changes on rest of driver to use this new APIs. -- 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.c b/drivers/gpio/gpiolib.c index 5c1ba87..d9a40bc 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -462,6 +462,80 @@ void gpiochip_remove(struct gpio_chip *chip) } EXPORT_SYMBOL_GPL(gpiochip_remove); +static void devm_gpio_chip_release(struct device *dev, void *res) +{ + struct gpio_chip *chip = *(struct gpio_chip **)res; + + gpiochip_remove(chip); +} + +static int devm_gpio_chip_match(struct device *dev, void *res, void *data) + +{ + struct gpio_chip **r = res; + + if (!r || !*r) { + WARN_ON(!r || !*r); + return 0; + } + + return *r == data; +} + +/** + * devm_gpiochip_add_data() - Resource manager piochip_add_data() + * @dev: the device pointer on which irq_chip belongs to. + * @chip: the chip to register, with chip->base initialized + * Context: potentially before irqs will work + * + * Returns a negative errno if the chip can't be registered, such as + * because the chip->base is invalid or already associated with a + * different chip. Otherwise it returns zero as a success code. + * + * The gpio chip automatically be released when the device is unbound. + */ +int devm_gpiochip_add_data(struct device *dev, struct gpio_chip *chip, + void *data) +{ + struct gpio_chip **ptr; + int ret; + + ptr = devres_alloc(devm_gpio_chip_release, sizeof(*ptr), + GFP_KERNEL); + if (!ptr) + return -ENOMEM; + + ret = gpiochip_add_data(chip, data); + if (ret < 0) { + devres_free(ptr); + return ret; + } + + *ptr = chip; + devres_add(dev, ptr); + + return 0; +} +EXPORT_SYMBOL_GPL(devm_gpiochip_add_data); + +/** + * devm_gpiochip_remove() - Resource manager of gpiochip_remove() + * @dev: device for which which resource was allocated + * @chip: the chip to remove + * + * A gpio_chip with any GPIOs still requested may not be removed. + */ +void devm_gpiochip_remove(struct device *dev, struct gpio_chip *chip) +{ + int ret; + + ret = devres_release(dev, devm_gpio_chip_release, + devm_gpio_chip_match, chip); + if (!ret) + WARN_ON(ret); +} +EXPORT_SYMBOL_GPL(devm_gpiochip_remove); + /** * gpiochip_find() - iterator for locating a specific gpio_chip * @data: data to pass to match function diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h index 82fda48..d5d19cc 100644 --- a/include/linux/gpio/driver.h +++ b/include/linux/gpio/driver.h @@ -205,6 +205,10 @@ static inline int gpiochip_add(struct gpio_chip *chip) return gpiochip_add_data(chip, NULL); } extern void gpiochip_remove(struct gpio_chip *chip); +extern int devm_gpiochip_add_data(struct device *dev, struct gpio_chip *chip, + void *data); +extern void devm_gpiochip_remove(struct device *dev, struct gpio_chip *chip); + extern struct gpio_chip *gpiochip_find(void *data, int (*match)(struct gpio_chip *chip, void *data));
Add device managed APIs devm_gpiochip_add_data() and devm_gpiochip_remove() for the APIs gpiochip_add_data() and gpiochip_remove(). This helps in reducing code in error path and sometimes removal of .remove callback for driver unbind. Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com> --- drivers/gpio/gpiolib.c | 74 +++++++++++++++++++++++++++++++++++++++++++++ include/linux/gpio/driver.h | 4 +++ 2 files changed, 78 insertions(+)