video: mxsfb: Introduce regulator support

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@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

diff --git a/Documentation/devicetree/bindings/fb/mxsfb.txt b/Documentation/devicetree/bindings/fb/mxsfb.txt
index 7ba3b76635138b812d0ce134fce41238712a8787..96ec5179c8a00199e2056ee574c3c55aef37bae3 100644 (file)
--- a/Documentation/devicetree/bindings/fb/mxsfb.txt
+++ b/Documentation/devicetree/bindings/fb/mxsfb.txt
@@ -7,9 +7,6 @@ Required properties:
 - interrupts: Should contain lcdif interrupts
 - display : phandle to display node (see below for details)
 
-Optional properties:
-- panel-enable-gpios : Should specify the gpio for panel enable
-
 * display node
 
 Required properties:
@@ -25,7 +22,6 @@ lcdif@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 7880e17e27f52a0d3c9b355ab062ff174a658a7e..da0588a041317f91c20a384c8cce6794b0d1d4df 100644 (file)
--- a/arch/arm/boot/dts/imx23-evk.dts
+++ b/arch/arm/boot/dts/imx23-evk.dts
@@ -59,7 +59,7 @@
                        lcdif@80030000 {
                                pinctrl-names = "default";
                                pinctrl-0 = <&lcdif_24bit_pins_a>;
-                               panel-enable-gpios = <&gpio1 18 0>;
+                               lcd-supply = <&reg_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 2d4ea3bfff4cf1a68f7c9a0b32ac43abbc187025..3637bf3b1d597c6690bd34c5f7e4b8109104043d 100644 (file)
--- 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 = <&reg_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 eac7c1ace7a583509554987dbc57dc896a776786..1b2c26d1658c65ed2fd73bb8a43462f537fe7f4a 100644 (file)
--- 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 (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);
 
@@ -362,6 +373,7 @@ 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__);
 
@@ -385,6 +397,13 @@ static void mxsfb_disable_controller(struct fb_info *fb_info)
        clk_disable_unprepare(host->clk);
 
        host->enabled = 0;
+
+       if (host->reg_lcd) {
+               ret = regulator_disable(host->reg_lcd);
+               if (ret)
+                       dev_err(&host->pdev->dev,
+                               "lcd regulator disable failed: %d\n", ret);
+       }
 }
 
 static int mxsfb_set_par(struct fb_info *fb_info)
@@ -859,8 +878,6 @@ 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 +921,9 @@ 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");
+       if (IS_ERR(host->reg_lcd))
+               host->reg_lcd = NULL;
 
        fb_info->pseudo_palette = devm_kzalloc(&pdev->dev, sizeof(u32) * 16,
                                               GFP_KERNEL);