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author | Sean Paul <seanpaul@chromium.org> | 2018-02-20 10:33:04 -0500 |
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committer | Sean Paul <seanpaul@chromium.org> | 2018-02-20 10:33:05 -0500 |
commit | f5155876af19f885fec94bbb926b0ce62115e139 (patch) | |
tree | f5d4a8d57ef2d7469e7bc9e3568fd9c9986202be | |
parent | 07d85290f9b6512d236a33e8617ee00f1b405ac2 (diff) | |
parent | 2e4ef3347b4a4eb65c4fd950d94bbd75fed4d798 (diff) | |
download | linux-f5155876af19f885fec94bbb926b0ce62115e139.tar.bz2 |
Merge tag 'topic/backlight_for_lag-2018-01-29' of git://anongit.freedesktop.org/drm/drm-misc into drm-misc-next
This contains the backlight portion of Meghana Madhyastha's patch set to
migrate the backlight helpers from tinydrm to the backlight subsystem.
https://patchwork.freedesktop.org/series/36522/
Cc: Meghana Madhyastha <meghana.madhyastha@gmail.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
# gpg: Signature made Mon 29 Jan 2018 02:25:40 PM EST
# gpg: using RSA key 7F17297CC4A076740CB3E42A96F70DFDA84A070A
# gpg: Good signature from "Sean Paul <seanpaul@chromium.org>" [unknown]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg: There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 1C5E AB9E D7C9 DDE9 E7F2 087C 732C 0025 72DC AF79
# Subkey fingerprint: 7F17 297C C4A0 7674 0CB3 E42A 96F7 0DFD A84A 070A
Link: https://patchwork.freedesktop.org/patch/msgid/20180129192950.bvmhkz3h42t5a25r@art_vandelay
-rw-r--r-- | drivers/video/backlight/backlight.c | 73 | ||||
-rw-r--r-- | include/linux/backlight.h | 58 |
2 files changed, 131 insertions, 0 deletions
diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c index 8049e7656daa..deb824bef6e2 100644 --- a/drivers/video/backlight/backlight.c +++ b/drivers/video/backlight/backlight.c @@ -580,6 +580,79 @@ struct backlight_device *of_find_backlight_by_node(struct device_node *node) EXPORT_SYMBOL(of_find_backlight_by_node); #endif +/** + * of_find_backlight - Get backlight device + * @dev: Device + * + * This function looks for a property named 'backlight' on the DT node + * connected to @dev and looks up the backlight device. + * + * Call backlight_put() to drop the reference on the backlight device. + * + * Returns: + * A pointer to the backlight device if found. + * Error pointer -EPROBE_DEFER if the DT property is set, but no backlight + * device is found. + * NULL if there's no backlight property. + */ +struct backlight_device *of_find_backlight(struct device *dev) +{ + struct backlight_device *bd = NULL; + struct device_node *np; + + if (!dev) + return NULL; + + if (IS_ENABLED(CONFIG_OF) && dev->of_node) { + np = of_parse_phandle(dev->of_node, "backlight", 0); + if (np) { + bd = of_find_backlight_by_node(np); + of_node_put(np); + if (!bd) + return ERR_PTR(-EPROBE_DEFER); + /* + * Note: gpio_backlight uses brightness as + * power state during probe + */ + if (!bd->props.brightness) + bd->props.brightness = bd->props.max_brightness; + } + } + + return bd; +} +EXPORT_SYMBOL(of_find_backlight); + +static void devm_backlight_release(void *data) +{ + backlight_put(data); +} + +/** + * devm_of_find_backlight - Resource-managed of_find_backlight() + * @dev: Device + * + * Device managed version of of_find_backlight(). + * The reference on the backlight device is automatically + * dropped on driver detach. + */ +struct backlight_device *devm_of_find_backlight(struct device *dev) +{ + struct backlight_device *bd; + int ret; + + bd = of_find_backlight(dev); + if (IS_ERR_OR_NULL(bd)) + return bd; + ret = devm_add_action(dev, devm_backlight_release, bd); + if (ret) { + backlight_put(bd); + return ERR_PTR(ret); + } + return bd; +} +EXPORT_SYMBOL(devm_of_find_backlight); + static void __exit backlight_class_exit(void) { class_destroy(backlight_class); diff --git a/include/linux/backlight.h b/include/linux/backlight.h index af7003548593..2baab6f3861d 100644 --- a/include/linux/backlight.h +++ b/include/linux/backlight.h @@ -130,6 +130,48 @@ static inline int backlight_update_status(struct backlight_device *bd) return ret; } +/** + * backlight_enable - Enable backlight + * @bd: the backlight device to enable + */ +static inline int backlight_enable(struct backlight_device *bd) +{ + if (!bd) + return 0; + + bd->props.power = FB_BLANK_UNBLANK; + bd->props.fb_blank = FB_BLANK_UNBLANK; + bd->props.state &= ~BL_CORE_FBBLANK; + + return backlight_update_status(bd); +} + +/** + * backlight_disable - Disable backlight + * @bd: the backlight device to disable + */ +static inline int backlight_disable(struct backlight_device *bd) +{ + if (!bd) + return 0; + + bd->props.power = FB_BLANK_POWERDOWN; + bd->props.fb_blank = FB_BLANK_POWERDOWN; + bd->props.state |= BL_CORE_FBBLANK; + + return backlight_update_status(bd); +} + +/** + * backlight_put - Drop backlight reference + * @bd: the backlight device to put + */ +static inline void backlight_put(struct backlight_device *bd) +{ + if (bd) + put_device(&bd->dev); +} + extern struct backlight_device *backlight_device_register(const char *name, struct device *dev, void *devdata, const struct backlight_ops *ops, const struct backlight_properties *props); @@ -173,4 +215,20 @@ of_find_backlight_by_node(struct device_node *node) } #endif +#if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE) +struct backlight_device *of_find_backlight(struct device *dev); +struct backlight_device *devm_of_find_backlight(struct device *dev); +#else +static inline struct backlight_device *of_find_backlight(struct device *dev) +{ + return NULL; +} + +static inline struct backlight_device * +devm_of_find_backlight(struct device *dev) +{ + return NULL; +} +#endif + #endif |