From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753390AbeASLGK (ORCPT ); Fri, 19 Jan 2018 06:06:10 -0500 Received: from mail-wm0-f65.google.com ([74.125.82.65]:40092 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755132AbeASLGA (ORCPT ); Fri, 19 Jan 2018 06:06:00 -0500 X-Google-Smtp-Source: ACJfBovFQbBEWZtZBuyEW8av8ZtwEfrd5MTWPKptoz3ztLzcxz1Lu90l2eXvqRafGth5pKdHOS7Mdg== Date: Fri, 19 Jan 2018 11:05:56 +0000 From: Daniel Thompson To: Meghana Madhyastha Cc: Lee Jones , Jingoo Han , Thierry Reding , Noralf =?iso-8859-1?Q?Tr=F8nnes?= , Tomi Valkeinen , Daniel Vetter , Sean Paul , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v17 03/10] video: backlight: Add of_find_backlight helper in backlight.c Message-ID: <20180119110556.q2z47isvdcnly2e2@oak.lan> References: <116d160ba78be2e6dcbdcb6855622bce67da9472.1516358037.git.meghana.madhyastha@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <116d160ba78be2e6dcbdcb6855622bce67da9472.1516358037.git.meghana.madhyastha@gmail.com> User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jan 19, 2018 at 10:42:15AM +0000, Meghana Madhyastha wrote: > Add of_find_backlight, a helper function which is a generic version > of tinydrm_of_find_backlight that can be used by other drivers to avoid > repetition of code and simplify things. > > Signed-off-by: Meghana Madhyastha Didn't I already ack this one? > --- > changes in v17: > -rebase with drm-misc-next > -convert st7735r callers from tinydrm specific helpers > to new generic backlight helpers > -remove select BACKLIGHT_LCD_SUPPORT > and select BACKLIGHT_CLASS_DEVICE from > tinydrm/Kconfig > > drivers/video/backlight/backlight.c | 43 +++++++++++++++++++++++++++++++++++++ > include/linux/backlight.h | 19 ++++++++++++++++ > 2 files changed, 62 insertions(+) > > diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c > index 8049e7656..553bf5c48 100644 > --- a/drivers/video/backlight/backlight.c > +++ b/drivers/video/backlight/backlight.c > @@ -580,6 +580,49 @@ 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 __exit backlight_class_exit(void) > { > class_destroy(backlight_class); > diff --git a/include/linux/backlight.h b/include/linux/backlight.h > index ace825e2c..ddc9bade4 100644 > --- a/include/linux/backlight.h > +++ b/include/linux/backlight.h > @@ -162,6 +162,16 @@ static inline int backlight_disable(struct backlight_device *bd) > 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); > @@ -205,4 +215,13 @@ 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); > +#else > +static inline struct backlight_device *of_find_backlight(struct device *dev) > +{ > + return NULL; > +} > +#endif > + > #endif > -- > 2.11.0 >