[PATCH] gpio: stmpe: Add DT support for stmpe gpio

[Viresh Kumar <viresh.kumar@linaro.org>]

From: Vipul Kumar Samar <vipulkumar.samar@st.com>

This patch allows the STMPE GPIO driver to be successfully probed and
initialised when Device Tree support is enabled. Bindings are mentioned in
Documentation too.

Signed-off-by: Vipul Kumar Samar <vipulkumar.samar@st.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 Documentation/devicetree/bindings/gpio/gpio-stmpe.txt | 18 ++++++++++++++++++
 drivers/gpio/gpio-stmpe.c                             | 15 ++++++++++++---
 drivers/mfd/stmpe.c                                   |  2 ++
 3 files changed, 32 insertions(+), 3 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/gpio/gpio-stmpe.txt

diff --git a/Documentation/devicetree/bindings/gpio/gpio-stmpe.txt b/Documentation/devicetree/bindings/gpio/gpio-stmpe.txt
new file mode 100644
index 0000000..7f010e0
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/gpio-stmpe.txt
@@ -0,0 +1,18 @@
+STMPE gpio
+----------
+
+Required properties:
+ - compatible: "st,stmpe-gpio"
+
+Optional properties:
+ - norequest-mask: bitmask specifying which GPIOs should _not_ be requestable
+   due to different usage (e.g. touch, keypad)
+
+Node name must be stmpe_gpio and should be child node of stmpe node to which it
+belongs.
+
+Example:
+	stmpe_gpio {
+		compatible = "st,stmpe-gpio";
+		st,norequest-mask = <0x20>;	//gpio 5 can't be used
+	};
diff --git a/drivers/gpio/gpio-stmpe.c b/drivers/gpio/gpio-stmpe.c
index dce3472..91455d4 100644
--- a/drivers/gpio/gpio-stmpe.c
+++ b/drivers/gpio/gpio-stmpe.c
@@ -12,6 +12,7 @@
 #include <linux/gpio.h>
 #include <linux/irq.h>
 #include <linux/interrupt.h>
+#include <linux/of.h>
 #include <linux/mfd/stmpe.h>
 
 /*
@@ -304,6 +305,7 @@ static void stmpe_gpio_irq_remove(struct stmpe_gpio *stmpe_gpio)
 static int __devinit stmpe_gpio_probe(struct platform_device *pdev)
 {
 	struct stmpe *stmpe = dev_get_drvdata(pdev->dev.parent);
+	struct device_node *np = pdev->dev.of_node;
 	struct stmpe_gpio_platform_data *pdata;
 	struct stmpe_gpio *stmpe_gpio;
 	int ret;
@@ -321,12 +323,19 @@ static int __devinit stmpe_gpio_probe(struct platform_device *pdev)
 
 	stmpe_gpio->dev = &pdev->dev;
 	stmpe_gpio->stmpe = stmpe;
-	stmpe_gpio->norequest_mask = pdata ? pdata->norequest_mask : 0;
-
 	stmpe_gpio->chip = template_chip;
 	stmpe_gpio->chip.ngpio = stmpe->num_gpios;
 	stmpe_gpio->chip.dev = &pdev->dev;
-	stmpe_gpio->chip.base = pdata ? pdata->gpio_base : -1;
+
+	if (pdata) {
+		stmpe_gpio->norequest_mask = pdata->norequest_mask;
+		stmpe_gpio->chip.base = pdata->gpio_base;
+	} else {
+		stmpe_gpio->chip.base = -1;
+		if (np)
+			of_property_read_u32(np, "st,norequest-mask",
+					&pdata->norequest_mask);
+	}
 
 	if (irq >= 0)
 		stmpe_gpio->irq_base = stmpe->irq_base + STMPE_INT_GPIO(0);
diff --git a/drivers/mfd/stmpe.c b/drivers/mfd/stmpe.c
index e2c0dda..c757ac3 100644
--- a/drivers/mfd/stmpe.c
+++ b/drivers/mfd/stmpe.c
@@ -298,12 +298,14 @@ static struct resource stmpe_gpio_resources[] = {
 
 static struct mfd_cell stmpe_gpio_cell = {
 	.name		= "stmpe-gpio",
+	.of_compatible	= "st,stmpe-gpio",
 	.resources	= stmpe_gpio_resources,
 	.num_resources	= ARRAY_SIZE(stmpe_gpio_resources),
 };
 
 static struct mfd_cell stmpe_gpio_cell_noirq = {
 	.name		= "stmpe-gpio",
+	.of_compatible	= "st,stmpe-gpio",
 	/* gpio cell resources consist of an irq only so no resources here */
 };
 
-- 
1.7.12.rc2.18.g61b472e