diff options
Diffstat (limited to 'drivers/leds/led-class.c')
-rw-r--r-- | drivers/leds/led-class.c | 138 |
1 files changed, 118 insertions, 20 deletions
diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c index 6a8ea94834fa..0c4b8d8d2b4f 100644 --- a/drivers/leds/led-class.c +++ b/drivers/leds/led-class.c @@ -23,6 +23,8 @@ #include "leds.h" static struct class *leds_class; +static DEFINE_MUTEX(leds_lookup_lock); +static LIST_HEAD(leds_lookup_list); static ssize_t brightness_show(struct device *dev, struct device_attribute *attr, char *buf) @@ -215,6 +217,23 @@ static int led_resume(struct device *dev) static SIMPLE_DEV_PM_OPS(leds_class_dev_pm_ops, led_suspend, led_resume); +static struct led_classdev *led_module_get(struct device *led_dev) +{ + struct led_classdev *led_cdev; + + if (!led_dev) + return ERR_PTR(-EPROBE_DEFER); + + led_cdev = dev_get_drvdata(led_dev); + + if (!try_module_get(led_cdev->dev->parent->driver->owner)) { + put_device(led_cdev->dev); + return ERR_PTR(-ENODEV); + } + + return led_cdev; +} + /** * of_led_get() - request a LED device via the LED framework * @np: device node to get the LED device from @@ -226,7 +245,6 @@ static SIMPLE_DEV_PM_OPS(leds_class_dev_pm_ops, led_suspend, led_resume); struct led_classdev *of_led_get(struct device_node *np, int index) { struct device *led_dev; - struct led_classdev *led_cdev; struct device_node *led_node; led_node = of_parse_phandle(np, "leds", index); @@ -236,15 +254,7 @@ struct led_classdev *of_led_get(struct device_node *np, int index) led_dev = class_find_device_by_of_node(leds_class, led_node); of_node_put(led_node); - if (!led_dev) - return ERR_PTR(-EPROBE_DEFER); - - led_cdev = dev_get_drvdata(led_dev); - - if (!try_module_get(led_cdev->dev->parent->driver->owner)) - return ERR_PTR(-ENODEV); - - return led_cdev; + return led_module_get(led_dev); } EXPORT_SYMBOL_GPL(of_led_get); @@ -255,6 +265,7 @@ EXPORT_SYMBOL_GPL(of_led_get); void led_put(struct led_classdev *led_cdev) { module_put(led_cdev->dev->parent->driver->owner); + put_device(led_cdev->dev); } EXPORT_SYMBOL_GPL(led_put); @@ -265,6 +276,22 @@ static void devm_led_release(struct device *dev, void *res) led_put(*p); } +static struct led_classdev *__devm_led_get(struct device *dev, struct led_classdev *led) +{ + struct led_classdev **dr; + + dr = devres_alloc(devm_led_release, sizeof(struct led_classdev *), GFP_KERNEL); + if (!dr) { + led_put(led); + return ERR_PTR(-ENOMEM); + } + + *dr = led; + devres_add(dev, dr); + + return led; +} + /** * devm_of_led_get - Resource-managed request of a LED device * @dev: LED consumer @@ -280,7 +307,6 @@ struct led_classdev *__must_check devm_of_led_get(struct device *dev, int index) { struct led_classdev *led; - struct led_classdev **dr; if (!dev) return ERR_PTR(-EINVAL); @@ -289,19 +315,91 @@ struct led_classdev *__must_check devm_of_led_get(struct device *dev, if (IS_ERR(led)) return led; - dr = devres_alloc(devm_led_release, sizeof(struct led_classdev *), - GFP_KERNEL); - if (!dr) { - led_put(led); - return ERR_PTR(-ENOMEM); + return __devm_led_get(dev, led); +} +EXPORT_SYMBOL_GPL(devm_of_led_get); + +/** + * led_get() - request a LED device via the LED framework + * @dev: device for which to get the LED device + * @con_id: name of the LED from the device's point of view + * + * @return a pointer to a LED device or ERR_PTR(errno) on failure. + */ +struct led_classdev *led_get(struct device *dev, char *con_id) +{ + struct led_lookup_data *lookup; + const char *provider = NULL; + struct device *led_dev; + + mutex_lock(&leds_lookup_lock); + list_for_each_entry(lookup, &leds_lookup_list, list) { + if (!strcmp(lookup->dev_id, dev_name(dev)) && + !strcmp(lookup->con_id, con_id)) { + provider = kstrdup_const(lookup->provider, GFP_KERNEL); + break; + } } + mutex_unlock(&leds_lookup_lock); - *dr = led; - devres_add(dev, dr); + if (!provider) + return ERR_PTR(-ENOENT); - return led; + led_dev = class_find_device_by_name(leds_class, provider); + kfree_const(provider); + + return led_module_get(led_dev); } -EXPORT_SYMBOL_GPL(devm_of_led_get); +EXPORT_SYMBOL_GPL(led_get); + +/** + * devm_led_get() - request a LED device via the LED framework + * @dev: device for which to get the LED device + * @con_id: name of the LED from the device's point of view + * + * The LED device returned from this function is automatically released + * on driver detach. + * + * @return a pointer to a LED device or ERR_PTR(errno) on failure. + */ +struct led_classdev *devm_led_get(struct device *dev, char *con_id) +{ + struct led_classdev *led; + + led = led_get(dev, con_id); + if (IS_ERR(led)) + return led; + + return __devm_led_get(dev, led); +} +EXPORT_SYMBOL_GPL(devm_led_get); + +/** + * led_add_lookup() - Add a LED lookup table entry + * @led_lookup: the lookup table entry to add + * + * Add a LED lookup table entry. On systems without devicetree the lookup table + * is used by led_get() to find LEDs. + */ +void led_add_lookup(struct led_lookup_data *led_lookup) +{ + mutex_lock(&leds_lookup_lock); + list_add_tail(&led_lookup->list, &leds_lookup_list); + mutex_unlock(&leds_lookup_lock); +} +EXPORT_SYMBOL_GPL(led_add_lookup); + +/** + * led_remove_lookup() - Remove a LED lookup table entry + * @led_lookup: the lookup table entry to remove + */ +void led_remove_lookup(struct led_lookup_data *led_lookup) +{ + mutex_lock(&leds_lookup_lock); + list_del(&led_lookup->list); + mutex_unlock(&leds_lookup_lock); +} +EXPORT_SYMBOL_GPL(led_remove_lookup); static int led_classdev_next_name(const char *init_name, char *name, size_t len) |