Input: egalax_ts - get gpio from devicetree

The irq_to_gpio() is old, most platforms use GENERIC_GPIO framework
and don't support this API anymore.

The i.MX6q sabrelite platform equips an egalax touchscreen controller,
and this platform already transfered to GENERIC_GPIO framework, to
support this driver, we use a more generic way to get gpio.

Add a return value checking for waking up the controller in the probe
function, this guarantee only a workable device can pass init.

[dmitry.torokhov@gmail.com: Make driver depend on CONFIG_OF as it is
 now required.]

Acked-by Zhang Jiejing <jiejing.zhang@freescale.com>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Hui Wang <jason77.wang@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

3 files changed, 41 insertions, 3 deletions

diff --git a/Documentation/devicetree/bindings/input/touchscreen/egalax-ts.txt b/Documentation/devicetree/bindings/input/touchscreen/egalax-ts.txt
new file mode 100644
index 000000000000..df70318a617f
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/touchscreen/egalax-ts.txt
@@ -0,0 +1,19 @@
+* EETI eGalax Multiple Touch Controller
+
+Required properties:
+- compatible: must be "eeti,egalax_ts"
+- reg: i2c slave address
+- interrupt-parent: the phandle for the interrupt controller
+- interrupts: touch controller interrupt
+- wakeup-gpios: the gpio pin to be used for waking up the controller
+  as well as uased as irq pin
+
+Example:
+
+        egalax_ts@04 {
+                compatible = "eeti,egalax_ts";
+                reg = <0x04>;
+                interrupt-parent = <&gpio1>;
+                interrupts = <9 2>;
+                wakeup-gpios = <&gpio1 9 0>;
+        };
diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index 1ba232cbc09d..f7668b24c378 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -239,7 +239,7 @@ config TOUCHSCREEN_EETI
 
 config TOUCHSCREEN_EGALAX
         tristate "EETI eGalax multi-touch panel support"
-        depends on I2C
+        depends on I2C && OF
         help
           Say Y here to enable support for I2C connected EETI
           eGalax multi-touch panels.
diff --git a/drivers/input/touchscreen/egalax_ts.c b/drivers/input/touchscreen/egalax_ts.c
index c1e3460f1195..13fa62fdfb0b 100644
--- a/drivers/input/touchscreen/egalax_ts.c
+++ b/drivers/input/touchscreen/egalax_ts.c
@@ -28,6 +28,7 @@
 #include <linux/slab.h>
 #include <linux/bitops.h>
 #include <linux/input/mt.h>
+#include <linux/of_gpio.h>
 
 /*
  * Mouse Mode: some panel may configure the controller to mouse mode,
@@ -122,9 +123,17 @@ static irqreturn_t egalax_ts_interrupt(int irq, void *dev_id)
 /* wake up controller by an falling edge of interrupt gpio.  */
 static int egalax_wake_up_device(struct i2c_client *client)
 {
-        int gpio = irq_to_gpio(client->irq);
+        struct device_node *np = client->dev.of_node;
+        int gpio;
         int ret;
 
+        if (!np)
+                return -ENODEV;
+
+        gpio = of_get_named_gpio(np, "wakeup-gpios", 0);
+        if (!gpio_is_valid(gpio))
+                return -ENODEV;
+
         ret = gpio_request(gpio, "egalax_irq");
         if (ret < 0) {
                 dev_err(&client->dev,
@@ -181,7 +190,11 @@ static int __devinit egalax_ts_probe(struct i2c_client *client,
         ts->input_dev = input_dev;
 
         /* controller may be in sleep, wake it up. */
-        egalax_wake_up_device(client);
+        error = egalax_wake_up_device(client);
+        if (error) {
+                dev_err(&client->dev, "Failed to wake up the controller\n");
+                goto err_free_dev;
+        }
 
         ret = egalax_firmware_version(client);
         if (ret < 0) {
@@ -274,11 +287,17 @@ static int egalax_ts_resume(struct device *dev)
 
 static SIMPLE_DEV_PM_OPS(egalax_ts_pm_ops, egalax_ts_suspend, egalax_ts_resume);
 
+static struct of_device_id egalax_ts_dt_ids[] = {
+        { .compatible = "eeti,egalax_ts" },
+        { /* sentinel */ }
+};
+
 static struct i2c_driver egalax_ts_driver = {
         .driver = {
                 .name   = "egalax_ts",
                 .owner  = THIS_MODULE,
                 .pm     = &egalax_ts_pm_ops,
+                .of_match_table = of_match_ptr(egalax_ts_dt_ids),
         },
         .id_table       = egalax_ts_id,
         .probe          = egalax_ts_probe,