[PATCH v4 0/4] simplefb: Add regulator handling support

@@ -61,7 +61,7 @@
 		#size-cells = <1>;
 		ranges;
 
-		framebuffer@0 {
+		simplefb_hdmi: framebuffer@0 {
 			compatible = "allwinner,simple-framebuffer",
 				     "simple-framebuffer";
 			allwinner,pipeline = "de_be0-lcd0-hdmi";

@@ -69,7 +69,7 @@
 			status = "disabled";
 		};
 
-		framebuffer@1 {
+		simplefb_lcd: framebuffer@1 {
 			compatible = "allwinner,simple-framebuffer",
 				     "simple-framebuffer";
 			allwinner,pipeline = "de_be0-lcd0";

@@ -47,10 +47,14 @@ Required properties:
   - a8b8g8r8 (32-bit pixels, d[31:24]=a, d[23:16]=b, d[15:8]=g, d[7:0]=r).
 
 Optional properties:
-- clocks : List of clocks used by the framebuffer. Clocks listed here
-           are expected to already be configured correctly. The OS must
-           ensure these clocks are not modified or disabled while the
-           simple framebuffer remains active.
+- clocks : List of clocks used by the framebuffer.
+- *-supply : Any number of regulators used by the framebuffer. These should
+	     be named according to the names in the device's design.
+
+  The above resources are expected to already be configured correctly.
+  The OS must ensure they are not modified or disabled while the simple
+  framebuffer remains active.
+
 - display : phandle pointing to the primary display hardware node
 
 Example:

@@ -68,6 +72,7 @@ chosen {
 		stride = <(1600 * 2)>;
 		format = "r5g6b5";
 		clocks = <&ahb_gates 36>, <&ahb_gates 43>, <&ahb_gates 44>;
+		lcd-supply = <&reg_dc1sw>;
 		display = <&lcdc0>;
 	};
 	stdout-path = "display0";

@@ -28,7 +28,10 @@
 #include <linux/platform_device.h>
 #include <linux/clk.h>
 #include <linux/clk-provider.h>
+#include <linux/of.h>
 #include <linux/of_platform.h>
+#include <linux/parser.h>
+#include <linux/regulator/consumer.h>
 
 static struct fb_fix_screeninfo simplefb_fix = {
 	.id		= "simple",

@@ -174,6 +177,10 @@ struct simplefb_par {
 	int clk_count;
 	struct clk **clks;
 #endif
+#if defined CONFIG_OF && defined CONFIG_REGULATOR
+	u32 regulator_count;
+	struct regulator **regulators;
+#endif
 };
 
 #if defined CONFIG_OF && defined CONFIG_COMMON_CLK

@@ -269,6 +276,110 @@ static int simplefb_clocks_init(struct simplefb_par *par,
 static void simplefb_clocks_destroy(struct simplefb_par *par) { }
 #endif
 
+#if defined CONFIG_OF && defined CONFIG_REGULATOR
+
+#define SUPPLY_SUFFIX "-supply"
+
+/*
+ * Regulator handling code.
+ *
+ * Here we handle the num-supplies and vin*-supply properties of our
+ * "simple-framebuffer" dt node. This is necessary so that we can make sure
+ * that any regulators needed by the display hardware that the bootloader
+ * set up for us (and for which it provided a simplefb dt node), stay up,
+ * for the life of the simplefb driver.
+ *
+ * When the driver unloads, we cleanly disable, and then release the
+ * regulators.
+ *
+ * We only complain about errors here, no action is taken as the most likely
+ * error can only happen due to a mismatch between the bootloader which set
+ * up simplefb, and the regulator definitions in the device tree. Chances are
+ * that there are no adverse effects, and if there are, a clean teardown of
+ * the fb probe will not help us much either. So just complain and carry on,
+ * and hope that the user actually gets a working fb at the end of things.
+ */
+static int simplefb_regulators_init(struct simplefb_par *par,
+	struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct property *prop;
+	struct regulator *regulator;
+	const char *p;
+	int count = 0, i = 0, ret;
+
+	if (dev_get_platdata(&pdev->dev) || !np)
+		return 0;
+
+	/* Count the number of regulator supplies */
+	for_each_property_of_node(np, prop) {
+		p = strstr(prop->name, SUPPLY_SUFFIX);
+		if (p && p != prop->name)
+			count++;
+	}
+
+	if (!count)
+		return 0;
+
+	par->regulators = devm_kcalloc(&pdev->dev, count,
+				       sizeof(struct regulator *), GFP_KERNEL);
+	if (!par->regulators)
+		return -ENOMEM;
+
+	/* Get all the regulators */
+	for_each_property_of_node(np, prop) {
+		char name[32]; /* 32 is max size of property name */
+
+		p = strstr(prop->name, SUPPLY_SUFFIX);
+		if (!p || p = prop->name)
+			continue;
+
+		strlcpy(name, prop->name,
+			strlen(prop->name) - strlen(SUPPLY_SUFFIX) + 1);
+		regulator = devm_regulator_get_optional(&pdev->dev, name);
+		if (IS_ERR(regulator)) {
+			if (PTR_ERR(regulator) = -EPROBE_DEFER)
+				return -EPROBE_DEFER;
+			dev_err(&pdev->dev, "regulator %s not found: %ld\n",
+				name, PTR_ERR(regulator));
+			continue;
+		}
+		par->regulators[i++] = regulator;
+	}
+	par->regulator_count = i;
+
+	/* Enable all the regulators */
+	for (i = 0; i < par->regulator_count; i++) {
+		ret = regulator_enable(par->regulators[i]);
+		if (ret) {
+			dev_err(&pdev->dev,
+				"failed to enable regulator %d: %d\n",
+				i, ret);
+			devm_regulator_put(par->regulators[i]);
+			par->regulators[i] = NULL;
+		}
+	}
+
+	return 0;
+}
+
+static void simplefb_regulators_destroy(struct simplefb_par *par)
+{
+	int i;
+
+	if (!par->regulators)
+		return;
+
+	for (i = 0; i < par->regulator_count; i++)
+		if (par->regulators[i])
+			regulator_disable(par->regulators[i]);
+}
+#else
+static int simplefb_regulators_init(struct simplefb_par *par,
+	struct platform_device *pdev) { return 0; }
+static void simplefb_regulators_destroy(struct simplefb_par *par) { }
+#endif
+
 static int simplefb_probe(struct platform_device *pdev)
 {
 	int ret;

@@ -340,6 +451,10 @@ static int simplefb_probe(struct platform_device *pdev)
 	if (ret < 0)
 		goto error_unmap;
 
+	ret = simplefb_regulators_init(par, pdev);
+	if (ret < 0)
+		goto error_clocks;
+
 	dev_info(&pdev->dev, "framebuffer at 0x%lx, 0x%x bytes, mapped to 0x%p\n",
 			     info->fix.smem_start, info->fix.smem_len,
 			     info->screen_base);

@@ -351,13 +466,15 @@ static int simplefb_probe(struct platform_device *pdev)
 	ret = register_framebuffer(info);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "Unable to register simplefb: %d\n", ret);
-		goto error_clocks;
+		goto error_regulators;
 	}
 
 	dev_info(&pdev->dev, "fb%d: simplefb registered!\n", info->node);
 
 	return 0;
 
+error_regulators:
+	simplefb_regulators_destroy(par);
 error_clocks:
 	simplefb_clocks_destroy(par);
 error_unmap:

@@ -373,6 +490,7 @@ static int simplefb_remove(struct platform_device *pdev)
 	struct simplefb_par *par = info->par;
 
 	unregister_framebuffer(info);
+	simplefb_regulators_destroy(par);
 	simplefb_clocks_destroy(par);
 	framebuffer_release(info);
 

@@ -612,6 +612,7 @@ dtb-$(CONFIG_MACH_SUN6I) += \
 	sun6i-a31-m9.dtb \
 	sun6i-a31-mele-a1000g-quad.dtb \
 	sun6i-a31s-cs908.dtb \
+	sun6i-a31s-primo81.dtb \
 	sun6i-a31s-sina31s.dtb \
 	sun6i-a31s-sinovoip-bpi-m2.dtb \
 	sun6i-a31s-yones-toptech-bs1078-v2.dtb

@@ -0,0 +1,255 @@
+/*
+ * Copyright 2014 Siarhei Siamashka <siarhei.siamashka@gmail.com>
+ * Copyright 2015 Karsten Merker <merker@debian.org>
+ * Copyright 2015 Chen-Yu Tsai <wens@csie.org>
+ *
+ * This file is dual-licensed: you can use it either under the terms
+ * of the GPL or the X11 license, at your option. Note that this dual
+ * licensing only applies to this file, and not this project as a
+ * whole.
+ *
+ *  a) This file is free software; you can redistribute it and/or
+ *     modify it under the terms of the GNU General Public License as
+ *     published by the Free Software Foundation; either version 2 of the
+ *     License, or (at your option) any later version.
+ *
+ *     This file is distributed in the hope that it will be useful,
+ *     but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *     GNU General Public License for more details.
+ *
+ * Or, alternatively,
+ *
+ *  b) Permission is hereby granted, free of charge, to any person
+ *     obtaining a copy of this software and associated documentation
+ *     files (the "Software"), to deal in the Software without
+ *     restriction, including without limitation the rights to use,
+ *     copy, modify, merge, publish, distribute, sublicense, and/or
+ *     sell copies of the Software, and to permit persons to whom the
+ *     Software is furnished to do so, subject to the following
+ *     conditions:
+ *
+ *     The above copyright notice and this permission notice shall be
+ *     included in all copies or substantial portions of the Software.
+ *
+ *     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ *     EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ *     OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ *     NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ *     HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ *     WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ *     FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ *     OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+/dts-v1/;
+#include "sun6i-a31s.dtsi"
+#include "sunxi-common-regulators.dtsi"
+
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/input/input.h>
+#include <dt-bindings/pinctrl/sun4i-a10.h>
+
+/ {
+	model = "MSI Primo81 tablet";
+	compatible = "msi,primo81", "allwinner,sun6i-a31s";
+};
+
+&cpu0 {
+	cpu-supply = <&reg_dcdc3>;
+};
+
+&ehci0 {
+	/* rtl8188etv wifi is connected here */
+	status = "okay";
+};
+
+&i2c0 {
+	/* pull-ups and device VDDIO use AXP221 DLDO3 */
+	pinctrl-names = "default";
+	pinctrl-0 = <&i2c0_pins_a>;
+	status = "failed";
+};
+
+&i2c1 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&i2c1_pins_a>;
+	status = "okay";
+
+	ctp@5d {
+		pinctrl-names = "default";
+		pinctrl-0 = <&gt911_int_primo81>;
+		compatible = "goodix,gt911";
+		reg = <0x5d>;
+		interrupt-parent = <&pio>;
+		interrupts = <0 3 IRQ_TYPE_LEVEL_HIGH>; /* PA3 */
+	};
+};
+
+&i2c2 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&i2c2_pins_a>;
+	status = "okay";
+
+	accelerometer@1c {
+		pinctrl-names = "default";
+		pinctrl-0 = <&mma8452_int_primo81>;
+		compatible = "fsl,mma8452";
+		reg = <0x1c>;
+		interrupt-parent = <&pio>;
+		interrupts = <0 9 IRQ_TYPE_LEVEL_HIGH>; /* PA9 */
+		#io-channel-cells = <1>;
+	};
+};
+
+&lradc {
+	vref-supply = <&reg_aldo3>;
+	status = "okay";
+
+	button@158 {
+		label = "Volume Up";
+		linux,code = <KEY_VOLUMEUP>;
+		channel = <0>;
+		voltage = <158730>;
+	};
+
+	button@349 {
+		label = "Volume Down";
+		linux,code = <KEY_VOLUMEDOWN>;
+		channel = <0>;
+		voltage = <349206>;
+	};
+};
+
+&mmc0 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&mmc0_pins_a>, <&mmc0_cd_pin_primo81>;
+	vmmc-supply = <&reg_dcdc1>;
+	bus-width = <4>;
+	cd-gpios = <&pio 0 8 GPIO_ACTIVE_HIGH>; /* PA8 */
+	cd-inverted;
+	status = "okay";
+};
+
+&pio {
+	gt911_int_primo81: gt911_int_pin@0 {
+		allwinner,pins = "PA3";
+		allwinner,function = "gpio_in";
+		allwinner,drive = <SUN4I_PINCTRL_10_MA>;
+		allwinner,pull = <SUN4I_PINCTRL_NO_PULL>;
+	};
+
+	mma8452_int_primo81: mma8452_int_pin@0 {
+		allwinner,pins = "PA9";
+		allwinner,function = "gpio_in";
+		allwinner,drive = <SUN4I_PINCTRL_10_MA>;
+		allwinner,pull = <SUN4I_PINCTRL_PULL_UP>;
+	};
+
+	mmc0_cd_pin_primo81: mmc0_cd_pin@0 {
+		allwinner,pins = "PA8";
+		allwinner,function = "gpio_in";
+		allwinner,drive = <SUN4I_PINCTRL_10_MA>;
+		allwinner,pull = <SUN4I_PINCTRL_PULL_UP>;
+	};
+};
+
+&p2wi {
+	status = "okay";
+
+	axp22x: pmic@68 {
+		compatible = "x-powers,axp221";
+		reg = <0x68>;
+		interrupt-parent = <&nmi_intc>;
+		interrupts = <0 IRQ_TYPE_LEVEL_LOW>;
+	};
+};
+
+#include "axp22x.dtsi"
+
+&reg_aldo3 {
+	regulator-always-on;
+	regulator-min-microvolt = <2700000>;
+	regulator-max-microvolt = <3300000>;
+	regulator-name = "avcc";
+};
+
+&reg_dc1sw {
+	regulator-min-microvolt = <3000000>;
+	regulator-max-microvolt = <3000000>;
+	regulator-name = "vcc-lcd";
+};
+
+&reg_dc5ldo {
+	regulator-min-microvolt = <700000>;
+	regulator-max-microvolt = <1320000>;
+	regulator-name = "vdd-cpus"; /* This is an educated guess */
+};
+
+&reg_dcdc1 {
+	regulator-always-on;
+	regulator-min-microvolt = <3000000>;
+	regulator-max-microvolt = <3000000>;
+	regulator-name = "vcc-3v0";
+};
+
+&reg_dcdc2 {
+	regulator-min-microvolt = <700000>;
+	regulator-max-microvolt = <1320000>;
+	regulator-name = "vdd-gpu";
+};
+
+&reg_dcdc3 {
+	regulator-always-on;
+	regulator-min-microvolt = <700000>;
+	regulator-max-microvolt = <1320000>;
+	regulator-name = "vdd-cpu";
+};
+
+&reg_dcdc4 {
+	regulator-always-on;
+	regulator-min-microvolt = <700000>;
+	regulator-max-microvolt = <1320000>;
+	regulator-name = "vdd-sys-dll";
+};
+
+&reg_dcdc5 {
+	regulator-always-on;
+	regulator-min-microvolt = <1500000>;
+	regulator-max-microvolt = <1500000>;
+	regulator-name = "vcc-dram";
+};
+
+&reg_dldo1 {
+	regulator-min-microvolt = <3300000>;
+	regulator-max-microvolt = <3300000>;
+	regulator-name = "vcc-wifi";
+};
+
+&reg_dldo3 {
+	regulator-min-microvolt = <2800000>;
+	regulator-max-microvolt = <2800000>;
+	regulator-name = "vddio-csi";
+};
+
+&reg_eldo3 {
+	regulator-min-microvolt = <1080000>;
+	regulator-max-microvolt = <1320000>;
+	regulator-name = "vdd-mipi-bridge";
+};
+
+&simplefb_lcd {
+	vcc-lcd-supply = <&reg_dc1sw>;
+	vdd-mipi-bridge-supply = <&reg_eldo3>;
+};
+
+&usb_otg {
+	/* otg support requires support for AXP221 usb-power-supply and GPIO */
+	dr_mode = "host";
+	status = "okay";
+};
+
+&usbphy {
+	usb1_vbus-supply = <&reg_dldo1>;
+	status = "okay";
+};