summaryrefslogtreecommitdiff
path: root/drivers/gpio/gpiolib-devres.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/gpio/gpiolib-devres.c')
-rw-r--r--drivers/gpio/gpiolib-devres.c80
1 files changed, 68 insertions, 12 deletions
diff --git a/drivers/gpio/gpiolib-devres.c b/drivers/gpio/gpiolib-devres.c
index 01959369360b..0acc2cc6e868 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;
@@ -321,6 +347,36 @@ void devm_gpiod_put(struct device *dev, struct gpio_desc *desc)
EXPORT_SYMBOL(devm_gpiod_put);
/**
+ * devm_gpiod_unhinge - Remove resource management from a gpio descriptor
+ * @dev: GPIO consumer
+ * @desc: GPIO descriptor to remove resource management from
+ *
+ * Remove resource management from a GPIO descriptor. This is needed when
+ * you want to hand over lifecycle management of a descriptor to another
+ * mechanism.
+ */
+
+void devm_gpiod_unhinge(struct device *dev, struct gpio_desc *desc)
+{
+ int ret;
+
+ if (IS_ERR_OR_NULL(desc))
+ return;
+ ret = devres_destroy(dev, devm_gpiod_release,
+ devm_gpiod_match, &desc);
+ /*
+ * If the GPIO descriptor is requested as nonexclusive, we
+ * may call this function several times on the same descriptor
+ * so it is OK if devres_destroy() returns -ENOENT.
+ */
+ if (ret == -ENOENT)
+ return;
+ /* Anything else we should warn about */
+ WARN_ON(ret);
+}
+EXPORT_SYMBOL(devm_gpiod_unhinge);
+
+/**
* devm_gpiod_put_array - Resource-managed gpiod_put_array()
* @dev: GPIO consumer
* @descs: GPIO descriptor array to dispose of