[PATCH v5] video: mxsfb: Introduce regulator support
Shawn Guo
shawn.guo at linaro.org
Sun Apr 7 02:33:44 EDT 2013
On Fri, Apr 05, 2013 at 11:19:47AM -0300, Fabio Estevam wrote:
> Instead of using a custom binding for retrieving the GPIO that activates the
> LCD from devicetree, use a standard regulator.
>
> This approach has the advantage to be more generic.
>
> For example: in the case of a board that has a PMIC supplying the LCD voltage,
> the current approach would not work, as it only searches for a GPIO pin.
>
> Signed-off-by: Fabio Estevam <fabio.estevam at freescale.com>
> ---
> Chages since v4:
> - Merged the 2 previous patches into one in order not to break keep mxsfb functionality
> - Remove unneeded change in mxsfb.txt
> - Use regulator_disable to pair with regulator_enable
> Changes since v3:
> - None
> Changes since v2:
> - Use devm_regulator_get()
> Changes since v1:
> - No changes
> Documentation/devicetree/bindings/fb/mxsfb.txt | 2 --
> arch/arm/boot/dts/imx23-evk.dts | 11 ++++++-
> arch/arm/boot/dts/imx28-evk.dts | 11 ++++++-
> drivers/video/mxsfb.c | 41 +++++++++++++-----------
> 4 files changed, 43 insertions(+), 22 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/fb/mxsfb.txt b/Documentation/devicetree/bindings/fb/mxsfb.txt
> index 7ba3b76..5d810eb 100644
> --- a/Documentation/devicetree/bindings/fb/mxsfb.txt
> +++ b/Documentation/devicetree/bindings/fb/mxsfb.txt
> @@ -8,7 +8,6 @@ Required properties:
> - display : phandle to display node (see below for details)
>
> Optional properties:
So this line should be removed together?
> -- panel-enable-gpios : Should specify the gpio for panel enable
>
> * display node
>
> @@ -25,7 +24,6 @@ lcdif at 80030000 {
> compatible = "fsl,imx28-lcdif";
> reg = <0x80030000 2000>;
> interrupts = <38 86>;
> - panel-enable-gpios = <&gpio3 30 0>;
>
> display: display {
> bits-per-pixel = <32>;
> diff --git a/arch/arm/boot/dts/imx23-evk.dts b/arch/arm/boot/dts/imx23-evk.dts
> index 7880e17..da0588a 100644
> --- a/arch/arm/boot/dts/imx23-evk.dts
> +++ b/arch/arm/boot/dts/imx23-evk.dts
> @@ -59,7 +59,7 @@
> lcdif at 80030000 {
> pinctrl-names = "default";
> pinctrl-0 = <&lcdif_24bit_pins_a>;
> - panel-enable-gpios = <&gpio1 18 0>;
> + lcd-supply = <®_lcd_3v3>;
> display = <&display>;
> status = "okay";
>
> @@ -120,6 +120,15 @@
> regulator-max-microvolt = <3300000>;
> gpio = <&gpio1 29 0>;
> };
> +
> + reg_lcd_3v3: lcd-3v3 {
> + compatible = "regulator-fixed";
> + regulator-name = "lcd-3v3";
> + regulator-min-microvolt = <3300000>;
> + regulator-max-microvolt = <3300000>;
> + gpio = <&gpio1 18 0>;
> + enable-active-high;
> + };
> };
>
> backlight {
> diff --git a/arch/arm/boot/dts/imx28-evk.dts b/arch/arm/boot/dts/imx28-evk.dts
> index 2d4ea3b..3637bf3 100644
> --- a/arch/arm/boot/dts/imx28-evk.dts
> +++ b/arch/arm/boot/dts/imx28-evk.dts
> @@ -123,7 +123,7 @@
> pinctrl-names = "default";
> pinctrl-0 = <&lcdif_24bit_pins_a
> &lcdif_pins_evk>;
> - panel-enable-gpios = <&gpio3 30 0>;
> + lcd-supply = <®_lcd_3v3>;
> display = <&display>;
> status = "okay";
>
> @@ -310,6 +310,15 @@
> gpio = <&gpio3 8 0>;
> enable-active-high;
> };
> +
> + reg_lcd_3v3: lcd-3v3 {
> + compatible = "regulator-fixed";
> + regulator-name = "lcd-3v3";
> + regulator-min-microvolt = <3300000>;
> + regulator-max-microvolt = <3300000>;
> + gpio = <&gpio3 30 0>;
> + enable-active-high;
> + };
> };
>
> sound {
> diff --git a/drivers/video/mxsfb.c b/drivers/video/mxsfb.c
> index eac7c1a..74fbfd1 100644
> --- a/drivers/video/mxsfb.c
> +++ b/drivers/video/mxsfb.c
> @@ -42,7 +42,6 @@
> #include <linux/module.h>
> #include <linux/kernel.h>
> #include <linux/of_device.h>
> -#include <linux/of_gpio.h>
> #include <video/of_display_timing.h>
> #include <linux/platform_device.h>
> #include <linux/clk.h>
> @@ -50,6 +49,7 @@
> #include <linux/io.h>
> #include <linux/pinctrl/consumer.h>
> #include <linux/fb.h>
> +#include <linux/regulator/consumer.h>
> #include <video/videomode.h>
>
> #define REG_SET 4
> @@ -179,6 +179,7 @@ struct mxsfb_info {
> unsigned dotclk_delay;
> const struct mxsfb_devdata *devdata;
> u32 sync;
> + struct regulator *reg_lcd;
> };
>
> #define mxsfb_is_v3(host) (host->devdata->ipversion == 3)
> @@ -338,9 +339,19 @@ static void mxsfb_enable_controller(struct fb_info *fb_info)
> {
> struct mxsfb_info *host = to_imxfb_host(fb_info);
> u32 reg;
> + int ret;
>
> dev_dbg(&host->pdev->dev, "%s\n", __func__);
>
> + if (!IS_ERR(host->reg_lcd)) {
> + ret = regulator_enable(host->reg_lcd);
> + if (ret) {
> + dev_err(&host->pdev->dev,
> + "lcd regulator enable failed: %d\n", ret);
> + return;
> + }
> + }
> +
> clk_prepare_enable(host->clk);
> clk_set_rate(host->clk, PICOS2KHZ(fb_info->var.pixclock) * 1000U);
>
> @@ -362,9 +373,19 @@ static void mxsfb_disable_controller(struct fb_info *fb_info)
> struct mxsfb_info *host = to_imxfb_host(fb_info);
> unsigned loop;
> u32 reg;
> + int ret;
>
> dev_dbg(&host->pdev->dev, "%s\n", __func__);
>
> + if (!IS_ERR(host->reg_lcd)) {
> + ret = regulator_disable(host->reg_lcd);
> + if (ret) {
> + dev_err(&host->pdev->dev,
> + "lcd regulator disable failed: %d\n", ret);
> + return;
> + }
> + }
> +
Shouldn't this be done as the last step of disabling?
> /*
> * Even if we disable the controller here, it will still continue
> * until its FIFOs are running out of data
> @@ -859,8 +880,6 @@ static int mxsfb_probe(struct platform_device *pdev)
> struct fb_info *fb_info;
> struct fb_modelist *modelist;
> struct pinctrl *pinctrl;
> - int panel_enable;
> - enum of_gpio_flags flags;
> int ret;
>
> if (of_id)
> @@ -904,21 +923,7 @@ static int mxsfb_probe(struct platform_device *pdev)
> goto fb_release;
> }
>
> - panel_enable = of_get_named_gpio_flags(pdev->dev.of_node,
> - "panel-enable-gpios", 0, &flags);
> - if (gpio_is_valid(panel_enable)) {
> - unsigned long f = GPIOF_OUT_INIT_HIGH;
> - if (flags == OF_GPIO_ACTIVE_LOW)
> - f = GPIOF_OUT_INIT_LOW;
> - ret = devm_gpio_request_one(&pdev->dev, panel_enable,
> - f, "panel-enable");
> - if (ret) {
> - dev_err(&pdev->dev,
> - "failed to request gpio %d: %d\n",
> - panel_enable, ret);
> - goto fb_release;
> - }
> - }
> + host->reg_lcd = devm_regulator_get(&pdev->dev, "lcd");
I prefer to check return here ...
if (IS_ERR(host->reg_lcd))
host->reg_lcd = NULL;
... and then use if (host->reg_lcd) in mxsfb_enable[disable]_controller().
Shawn
>
> fb_info->pseudo_palette = devm_kzalloc(&pdev->dev, sizeof(u32) * 16,
> GFP_KERNEL);
> --
> 1.7.9.5
>
>
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