From mboxrd@z Thu Jan 1 00:00:00 1970 From: Denis Carikli Subject: [Patch v2][ 06/37] video: backlight: gpio-backlight: Add DT support. Date: Thu, 17 Oct 2013 17:02:04 +0200 Message-ID: <1382022155-21954-7-git-send-email-denis@eukrea.com> References: <1382022155-21954-1-git-send-email-denis@eukrea.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <1382022155-21954-1-git-send-email-denis-fO0SIAKYzcbQT0dZR+AlfA@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Sascha Hauer Cc: linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, =?UTF-8?q?Eric=20B=C3=A9nard?= , Denis Carikli , Richard Purdie , Jingoo Han , Laurent Pinchart , Rob Herring , Pawel Moll , Mark Rutland , Stephen Warren , Ian Campbell , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: devicetree@vger.kernel.org Cc: Richard Purdie Cc: Jingoo Han Cc: Laurent Pinchart Cc: Rob Herring Cc: Pawel Moll Cc: Mark Rutland Cc: Stephen Warren Cc: Ian Campbell Cc: devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: Sascha Hauer Cc: linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org Cc: Eric B=C3=A9nard Signed-off-by: Denis Carikli --- .../bindings/video/backlight/gpio-backlight.txt | 18 +++++ drivers/video/backlight/gpio_backlight.c | 73 ++++++++++++= ++++++-- 2 files changed, 84 insertions(+), 7 deletions(-) create mode 100644 Documentation/devicetree/bindings/video/backlight/g= pio-backlight.txt diff --git a/Documentation/devicetree/bindings/video/backlight/gpio-bac= klight.txt b/Documentation/devicetree/bindings/video/backlight/gpio-bac= klight.txt new file mode 100644 index 0000000..362dd40 --- /dev/null +++ b/Documentation/devicetree/bindings/video/backlight/gpio-backlight.= txt @@ -0,0 +1,18 @@ +gpio-backlight bindings + +Required properties: + - compatible: "gpio-backlight" + - gpios: describes the gpio that is used for enabling/disabling the = backlight + (see GPIO binding[0] for more details). + - default-brightness-level: the default brightness level (can be 0(o= ff) or + 1(on) since GPIOs only support theses levels). + +[0]: Documentation/devicetree/bindings/gpio/gpio.txt + +Example: + + backlight { + compatible =3D "gpio-backlight"; + gpios =3D <&gpio3 4 0>; + default-brightness-level =3D <1>; + }; diff --git a/drivers/video/backlight/gpio_backlight.c b/drivers/video/b= acklight/gpio_backlight.c index 81fb127..f5d31e7 100644 --- a/drivers/video/backlight/gpio_backlight.c +++ b/drivers/video/backlight/gpio_backlight.c @@ -13,6 +13,8 @@ #include #include #include +#include +#include #include #include #include @@ -23,6 +25,7 @@ struct gpio_backlight { =20 int gpio; int active; + int def_value; }; =20 static int gpio_backlight_update_status(struct backlight_device *bl) @@ -60,6 +63,43 @@ static const struct backlight_ops gpio_backlight_ops= =3D { .check_fb =3D gpio_backlight_check_fb, }; =20 +static int gpio_backlight_probe_dt(struct platform_device *pdev, + struct gpio_backlight *gbl) +{ + struct device_node *np =3D pdev->dev.of_node; + enum of_gpio_flags gpio_flags; + int ret; + + gbl->fbdev =3D NULL; + gbl->gpio =3D of_get_gpio_flags(np, 0, &gpio_flags); + + gbl->active =3D (gpio_flags & OF_GPIO_ACTIVE_LOW) ? 0 : 1; + + if (gbl->gpio =3D=3D -EPROBE_DEFER) { + return ERR_PTR(-EPROBE_DEFER); + } else if (gbl->gpio < 0) { + dev_err(&pdev->dev, "Error: gpios is a required parameter.\n"); + return gbl->gpio; + } + + ret =3D of_property_read_u32(np, "default-brightness-level", + &gbl->def_value); + if (ret < 0) { + dev_err(&pdev->dev, "Error: default-brightness-level " + "is a required parameter.\n"); + return ret; + } + + if (gbl->def_value < 0 || gbl->def_value > 1) { + dev_err(&pdev->dev, "Error: Invalid " + "default-brightness-level value. Its value can be " + "either 0(off) or 1(on).\n"); + return -EINVAL; + } + + return 0; +} + static int gpio_backlight_probe(struct platform_device *pdev) { struct gpio_backlight_platform_data *pdata =3D @@ -67,10 +107,12 @@ static int gpio_backlight_probe(struct platform_de= vice *pdev) struct backlight_properties props; struct backlight_device *bl; struct gpio_backlight *gbl; + struct device_node *np =3D pdev->dev.of_node; int ret; =20 - if (!pdata) { - dev_err(&pdev->dev, "failed to find platform data\n"); + if (!pdata && !np) { + dev_err(&pdev->dev, "failed to find platform data or device " + "tree node.\n"); return -ENODEV; } =20 @@ -79,14 +121,21 @@ static int gpio_backlight_probe(struct platform_de= vice *pdev) return -ENOMEM; =20 gbl->dev =3D &pdev->dev; - gbl->fbdev =3D pdata->fbdev; - gbl->gpio =3D pdata->gpio; - gbl->active =3D pdata->active_low ? 0 : 1; + + if (np) { + ret =3D gpio_backlight_probe_dt(pdev, gbl); + if (ret) + return ret; + } else { + gbl->fbdev =3D pdata->fbdev; + gbl->gpio =3D pdata->gpio; + gbl->active =3D pdata->active_low ? 0 : 1; + } =20 ret =3D devm_gpio_request_one(gbl->dev, gbl->gpio, GPIOF_DIR_OUT | (gbl->active ? GPIOF_INIT_LOW : GPIOF_INIT_HIGH), - pdata->name); + pdata ? pdata->name : "backlight"); if (ret < 0) { dev_err(&pdev->dev, "unable to request GPIO\n"); return ret; @@ -103,17 +152,27 @@ static int gpio_backlight_probe(struct platform_d= evice *pdev) return PTR_ERR(bl); } =20 - bl->props.brightness =3D pdata->def_value; + if (np) + bl->props.brightness =3D gbl->def_value; + else + bl->props.brightness =3D pdata->def_value; + backlight_update_status(bl); =20 platform_set_drvdata(pdev, bl); return 0; } =20 +static struct of_device_id gpio_backlight_of_match[] =3D { + { .compatible =3D "gpio-backlight" }, + { /* sentinel */ } +}; + static struct platform_driver gpio_backlight_driver =3D { .driver =3D { .name =3D "gpio-backlight", .owner =3D THIS_MODULE, + .of_match_table =3D of_match_ptr(gpio_backlight_of_match), }, .probe =3D gpio_backlight_probe, }; --=20 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe devicetree" i= n the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html