| Message ID | 1382116250-8808-1-git-send-email-denis@eukrea.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 19:10 Fri 18 Oct , Denis Carikli wrote: > Cc: Richard Purdie <rpurdie@rpsys.net> > Cc: Jingoo Han <jg1.han@samsung.com> > Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > Cc: Rob Herring <rob.herring@calxeda.com> > Cc: Pawel Moll <pawel.moll@arm.com> > Cc: Mark Rutland <mark.rutland@arm.com> > Cc: Stephen Warren <swarren@wwwdotorg.org> > Cc: Ian Campbell <ijc+devicetree@hellion.org.uk> > Cc: devicetree@vger.kernel.org > Cc: Sascha Hauer <kernel@pengutronix.de> > Cc: linux-arm-kernel@lists.infradead.org > Cc: Lothar Waßmann <LW@KARO-electronics.de> > Cc: Eric Bénard <eric@eukrea.com> > Signed-off-by: Denis Carikli <denis@eukrea.com> > --- > ChangeLog v2->v3: > - The dev_err are not split between multiples lines anymore, in order to > improve grepping. Thanks to Lothar Waßmann for the advise. > --- > .../bindings/video/backlight/gpio-backlight.txt | 18 +++++ > drivers/video/backlight/gpio_backlight.c | 72 ++++++++++++++++++-- > 2 files changed, 83 insertions(+), 7 deletions(-) > create mode 100644 Documentation/devicetree/bindings/video/backlight/gpio-backlight.txt > > diff --git a/Documentation/devicetree/bindings/video/backlight/gpio-backlight.txt b/Documentation/devicetree/bindings/video/backlight/gpio-backlight.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(off) or > + 1(on) since GPIOs only support theses levels). > + > +[0]: Documentation/devicetree/bindings/gpio/gpio.txt > + > +Example: > + > + backlight { > + compatible = "gpio-backlight"; > + gpios = <&gpio3 4 0>; > + default-brightness-level = <1>; why mandatory if optionnal put 0 > + }; > diff --git a/drivers/video/backlight/gpio_backlight.c b/drivers/video/backlight/gpio_backlight.c > index 81fb127..3bf38a0 100644 > --- a/drivers/video/backlight/gpio_backlight.c > +++ b/drivers/video/backlight/gpio_backlight.c > @@ -13,6 +13,8 @@ > #include <linux/init.h> > #include <linux/kernel.h> > #include <linux/module.h> > +#include <linux/of.h> > +#include <linux/of_gpio.h> > #include <linux/platform_data/gpio_backlight.h> > #include <linux/platform_device.h> > #include <linux/slab.h> > @@ -23,6 +25,7 @@ struct gpio_backlight { > > int gpio; > int active; > + int def_value; > }; > > static int gpio_backlight_update_status(struct backlight_device *bl) > @@ -60,6 +63,42 @@ static const struct backlight_ops gpio_backlight_ops = { > .check_fb = gpio_backlight_check_fb, > }; > > +static int gpio_backlight_probe_dt(struct platform_device *pdev, > + struct gpio_backlight *gbl) > +{ > + struct device_node *np = pdev->dev.of_node; > + enum of_gpio_flags gpio_flags; > + int ret; > + > + gbl->fbdev = NULL; > + gbl->gpio = of_get_gpio_flags(np, 0, &gpio_flags); > + > + gbl->active = (gpio_flags & OF_GPIO_ACTIVE_LOW) ? 0 : 1; > + > + if (gbl->gpio == -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 = 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; > + } if > 1 force 1 and report a warning > + > + return 0; > +} > + > static int gpio_backlight_probe(struct platform_device *pdev) > { > struct gpio_backlight_platform_data *pdata = > @@ -67,10 +106,12 @@ static int gpio_backlight_probe(struct platform_device *pdev) > struct backlight_properties props; > struct backlight_device *bl; > struct gpio_backlight *gbl; > + struct device_node *np = pdev->dev.of_node; > int ret; > > - 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; > } > > @@ -79,14 +120,21 @@ static int gpio_backlight_probe(struct platform_device *pdev) > return -ENOMEM; > > gbl->dev = &pdev->dev; > - gbl->fbdev = pdata->fbdev; > - gbl->gpio = pdata->gpio; > - gbl->active = pdata->active_low ? 0 : 1; > + > + if (np) { > + ret = gpio_backlight_probe_dt(pdev, gbl); > + if (ret) > + return ret; > + } else { > + gbl->fbdev = pdata->fbdev; > + gbl->gpio = pdata->gpio; > + gbl->active = pdata->active_low ? 0 : 1; store the default value here gbl->def_value = pdata->def_value; > + } after here you does not need to care if it's dt or not > > ret = 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 +151,27 @@ static int gpio_backlight_probe(struct platform_device *pdev) > return PTR_ERR(bl); > } > > - bl->props.brightness = pdata->def_value; > + if (np) > + bl->props.brightness = gbl->def_value; > + else > + bl->props.brightness = pdata->def_value; so no need to check np again here > + > backlight_update_status(bl); > > platform_set_drvdata(pdev, bl); > return 0; > } > > +static struct of_device_id gpio_backlight_of_match[] = { > + { .compatible = "gpio-backlight" }, > + { /* sentinel */ } > +}; > + > static struct platform_driver gpio_backlight_driver = { > .driver = { > .name = "gpio-backlight", > .owner = THIS_MODULE, > + .of_match_table = of_match_ptr(gpio_backlight_of_match), > }, > .probe = gpio_backlight_probe, > }; > -- > 1.7.9.5 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
diff --git a/Documentation/devicetree/bindings/video/backlight/gpio-backlight.txt b/Documentation/devicetree/bindings/video/backlight/gpio-backlight.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(off) or + 1(on) since GPIOs only support theses levels). + +[0]: Documentation/devicetree/bindings/gpio/gpio.txt + +Example: + + backlight { + compatible = "gpio-backlight"; + gpios = <&gpio3 4 0>; + default-brightness-level = <1>; + }; diff --git a/drivers/video/backlight/gpio_backlight.c b/drivers/video/backlight/gpio_backlight.c index 81fb127..3bf38a0 100644 --- a/drivers/video/backlight/gpio_backlight.c +++ b/drivers/video/backlight/gpio_backlight.c @@ -13,6 +13,8 @@ #include <linux/init.h> #include <linux/kernel.h> #include <linux/module.h> +#include <linux/of.h> +#include <linux/of_gpio.h> #include <linux/platform_data/gpio_backlight.h> #include <linux/platform_device.h> #include <linux/slab.h> @@ -23,6 +25,7 @@ struct gpio_backlight { int gpio; int active; + int def_value; }; static int gpio_backlight_update_status(struct backlight_device *bl) @@ -60,6 +63,42 @@ static const struct backlight_ops gpio_backlight_ops = { .check_fb = gpio_backlight_check_fb, }; +static int gpio_backlight_probe_dt(struct platform_device *pdev, + struct gpio_backlight *gbl) +{ + struct device_node *np = pdev->dev.of_node; + enum of_gpio_flags gpio_flags; + int ret; + + gbl->fbdev = NULL; + gbl->gpio = of_get_gpio_flags(np, 0, &gpio_flags); + + gbl->active = (gpio_flags & OF_GPIO_ACTIVE_LOW) ? 0 : 1; + + if (gbl->gpio == -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 = 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 = @@ -67,10 +106,12 @@ static int gpio_backlight_probe(struct platform_device *pdev) struct backlight_properties props; struct backlight_device *bl; struct gpio_backlight *gbl; + struct device_node *np = pdev->dev.of_node; int ret; - 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; } @@ -79,14 +120,21 @@ static int gpio_backlight_probe(struct platform_device *pdev) return -ENOMEM; gbl->dev = &pdev->dev; - gbl->fbdev = pdata->fbdev; - gbl->gpio = pdata->gpio; - gbl->active = pdata->active_low ? 0 : 1; + + if (np) { + ret = gpio_backlight_probe_dt(pdev, gbl); + if (ret) + return ret; + } else { + gbl->fbdev = pdata->fbdev; + gbl->gpio = pdata->gpio; + gbl->active = pdata->active_low ? 0 : 1; + } ret = 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 +151,27 @@ static int gpio_backlight_probe(struct platform_device *pdev) return PTR_ERR(bl); } - bl->props.brightness = pdata->def_value; + if (np) + bl->props.brightness = gbl->def_value; + else + bl->props.brightness = pdata->def_value; + backlight_update_status(bl); platform_set_drvdata(pdev, bl); return 0; } +static struct of_device_id gpio_backlight_of_match[] = { + { .compatible = "gpio-backlight" }, + { /* sentinel */ } +}; + static struct platform_driver gpio_backlight_driver = { .driver = { .name = "gpio-backlight", .owner = THIS_MODULE, + .of_match_table = of_match_ptr(gpio_backlight_of_match), }, .probe = gpio_backlight_probe, };
Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Jingoo Han <jg1.han@samsung.com> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Cc: Rob Herring <rob.herring@calxeda.com> Cc: Pawel Moll <pawel.moll@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Stephen Warren <swarren@wwwdotorg.org> Cc: Ian Campbell <ijc+devicetree@hellion.org.uk> Cc: devicetree@vger.kernel.org Cc: Sascha Hauer <kernel@pengutronix.de> Cc: linux-arm-kernel@lists.infradead.org Cc: Lothar Waßmann <LW@KARO-electronics.de> Cc: Eric Bénard <eric@eukrea.com> Signed-off-by: Denis Carikli <denis@eukrea.com> --- ChangeLog v2->v3: - The dev_err are not split between multiples lines anymore, in order to improve grepping. Thanks to Lothar Waßmann for the advise. --- .../bindings/video/backlight/gpio-backlight.txt | 18 +++++ drivers/video/backlight/gpio_backlight.c | 72 ++++++++++++++++++-- 2 files changed, 83 insertions(+), 7 deletions(-) create mode 100644 Documentation/devicetree/bindings/video/backlight/gpio-backlight.txt