[Patch v5 08/13] ARM: imx6q: add config-on-boot gpios

Dear Rob Herring,

On 06/13/2012 07:34 AM, Richard Zhao wrote:

quoted

Sometimes, boards have gpios that don't own by any driver or owner
by a generic driver that don't like hacks. Such gpios is normally
output and need setup once on boot. So I introduce the config-on-boot
gpios.

Signed-off-by: Richard Zhao <redacted>
Cc: Shawn Guo <redacted>
Cc: Rob Herring <redacted>
Cc: Grant Likely <redacted>
---

 .../devicetree/bindings/arm/config-on-boot.txt     |   12 +++++++
 arch/arm/boot/dts/imx6q-sabrelite.dts              |    7 ++++
 arch/arm/mach-imx/mach-imx6q.c                     |   35
 ++++++++++++++++++++ 3 files changed, 54 insertions(+)
 create mode 100644
 Documentation/devicetree/bindings/arm/config-on-boot.txt

diff --git a/Documentation/devicetree/bindings/arm/config-on-boot.txt

b/Documentation/devicetree/bindings/arm/config-on-boot.txt new file mode
100644
index 0000000..f98ed74

--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/config-on-boot.txt

@@ -0,0 +1,12 @@
+* Configure on Boot
+
+Node name: config-on-boot
+  It must be in root node. config-on-boot means to describe settings

that needs +  to be set one time on boot but aren't owned by any driver,
or the owned driver +  is too generic to handle such settings. For
example, usb hub uses generic +  driver in usb core code, a on-board usb
may need deassert reset pin.

NAK. This is not a h/w description and should be solved within the
kernel or bootloader. Either fix this in u-boot

I don't want to be the bastard here, but this shouldn't go into uboot.

the platform code

Yes, it should be here. But then, it's some usb reset, so maybe the PHY should 
somehow handle it?

, or
make the generic driver support this in a generic way.

Well, this is platform specific stuff, so it shouldn't be in any way part of the 
driver.

Rob

quoted

+
+Optional properties:
+- output-gpios: Output gpio array that needs to set.
+- output-gpio-values: This property is required if output-gpios is set.
+  The value is a array of 0 or 1. Total count eaquals the number of
gpios. diff --git a/arch/arm/boot/dts/imx6q-sabrelite.dts
b/arch/arm/boot/dts/imx6q-sabrelite.dts index e0ec929..1dd2261 100644

--- a/arch/arm/boot/dts/imx6q-sabrelite.dts
+++ b/arch/arm/boot/dts/imx6q-sabrelite.dts

@@ -17,6 +17,13 @@

 	model = "Freescale i.MX6 Quad SABRE Lite Board";
 	compatible = "fsl,imx6q-sabrelite", "fsl,imx6q";

+	config-on-boot {
+		output-gpios = <
+				&gpio3 22 0>;	/* vbus reset */
+		output-gpio-values = <
+				1>;		/* vbus reset */
+	};
+

 	memory {
 	
 		reg = <0x10000000 0x40000000>;
 	
 	};

diff --git a/arch/arm/mach-imx/mach-imx6q.c

b/arch/arm/mach-imx/mach-imx6q.c index b47e98b..577cf19 100644

--- a/arch/arm/mach-imx/mach-imx6q.c
+++ b/arch/arm/mach-imx/mach-imx6q.c

@@ -19,6 +19,7 @@

 #include <linux/irqdomain.h>
 #include <linux/of.h>
 #include <linux/of_address.h>

+#include <linux/of_gpio.h>

 #include <linux/of_irq.h>
 #include <linux/of_platform.h>
 #include <linux/pinctrl/machine.h>

@@ -113,6 +114,38 @@ static void __init imx6q_sabrelite_init(void)

 	imx6q_sabrelite_cko1_setup();
 
 }

+static void __init imx6q_config_on_boot(void)
+{
+	struct device_node *np;
+	struct property *pp;
+	int cnt, len, i;
+	int gpio;
+
+	np = of_find_node_by_path("/config-on-boot");
+	if (!np)
+		return;
+	cnt = of_gpio_named_count(np, "output-gpios");
+	pp = of_find_property(np, "output-gpio-values", &len);
+	if (!pp || cnt != len / sizeof(u32)) {
+		pr_err("Invalid config-on-boot gpios!\n");
+		of_node_put(np);
+		return;
+	}
+	for (i = 0; i < cnt; i++) {
+		gpio = of_get_named_gpio(np, "output-gpios", i);
+		if (gpio_is_valid(gpio))
+			gpio_request_one(gpio, GPIOF_OUT_INIT_HIGH,
+					"config-on-boot");
+	}
+
+	of_node_put(np);
+}
+
+static void __init imx6q_post_populate(void)
+{
+	imx6q_config_on_boot();
+}
+

 static void __init imx6q_init_machine(void)
 {
 
 	/*

@@ -126,6 +159,8 @@ static void __init imx6q_init_machine(void)

 	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);

+	imx6q_post_populate();
+

 	imx6q_pm_init();
 
 }

Best regards,
Marek Vasut