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authorLinus Walleij <linus.walleij@linaro.org>2018-12-06 13:43:45 +0100
committerMark Brown <broonie@kernel.org>2018-12-11 01:04:17 +0000
commitcb28ee388e465a956b05ada682f9ef90e776a9b7 (patch)
treece072b8f8f8bac2520a923beded354992bed848c /drivers/gpio
parentec757001c818c175e6b610e8ef80c2a25d1ed1a5 (diff)
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: b0ce7b29bfcd ("regulator/gpio: Allow nonexclusive GPIO access") Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com> Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/gpio')
-rw-r--r--drivers/gpio/gpiolib-devres.c50
1 files changed, 38 insertions, 12 deletions
diff --git a/drivers/gpio/gpiolib-devres.c b/drivers/gpio/gpiolib-devres.c
index 01959369360b..f9591b5c9748 100644
--- a/drivers/gpio/gpiolib-devres.c
+++ b/drivers/gpio/gpiolib-devres.c
@@ -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;