Unverified Commit cb28ee38 authored by Linus Walleij's avatar Linus Walleij Committed by Mark Brown
Browse files

gpio: devres: Handle nonexclusive GPIOs 



When we get a nonexeclusive GPIO descriptor using managed
resources, we should only add it to the list of managed
resources once: on the first user. Augment the
devm_gpiod_get_index() and devm_gpiod_get_from_of_node()
calls to account for this by checking if the descriptor
is already resource managed before we proceed to allocate
a new resource management struct.

Fixes: b0ce7b29 ("regulator/gpio: Allow nonexclusive GPIO access")
Reported-by: default avatarMarek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: default avatarMarek Szyprowski <m.szyprowski@samsung.com>
Tested-by: default avatarMarek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: default avatarCharles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent ec757001

drivers/gpio/gpiolib-devres.c

+38 −12
Original line number Diff line number Diff line
@@ -98,15 +98,28 @@ struct gpio_desc *__must_check devm_gpiod_get_index(struct device *dev, 
	struct gpio_desc **dr;

	struct gpio_desc *desc;



	desc = gpiod_get_index(dev, con_id, idx, flags);

	if (IS_ERR(desc))

		return desc;



	/*

	 * For non-exclusive GPIO descriptors, check if this descriptor is

	 * already under resource management by this device.

	 */

	if (flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) {

		struct devres *dres;



		dres = devres_find(dev, devm_gpiod_release,

				   devm_gpiod_match, &desc);

		if (dres)

			return desc;

	}



	dr = devres_alloc(devm_gpiod_release, sizeof(struct gpio_desc *),

			  GFP_KERNEL);

	if (!dr)

	if (!dr) {

		gpiod_put(desc);

		return ERR_PTR(-ENOMEM);



	desc = gpiod_get_index(dev, con_id, idx, flags);

	if (IS_ERR(desc)) {

		devres_free(dr);

		return desc;

	}



	*dr = desc;
@@ -140,15 +153,28 @@ struct gpio_desc *devm_gpiod_get_from_of_node(struct device *dev, 
	struct gpio_desc **dr;

	struct gpio_desc *desc;



	desc = gpiod_get_from_of_node(node, propname, index, dflags, label);

	if (IS_ERR(desc))

		return desc;



	/*

	 * For non-exclusive GPIO descriptors, check if this descriptor is

	 * already under resource management by this device.

	 */

	if (dflags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) {

		struct devres *dres;



		dres = devres_find(dev, devm_gpiod_release,

				   devm_gpiod_match, &desc);

		if (dres)

			return desc;

	}



	dr = devres_alloc(devm_gpiod_release, sizeof(struct gpio_desc *),

			  GFP_KERNEL);

	if (!dr)

	if (!dr) {

		gpiod_put(desc);

		return ERR_PTR(-ENOMEM);



	desc = gpiod_get_from_of_node(node, propname, index, dflags, label);

	if (IS_ERR(desc)) {

		devres_free(dr);

		return desc;

	}



	*dr = desc;

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