Input: atmel_mxt_ts - implement device tree support

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

diff --git a/Documentation/devicetree/bindings/input/atmel,maxtouch.txt b/Documentation/devicetree/bindings/input/atmel,maxtouch.txt
new file mode 100644 (file)
index 0000000..baef432
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/atmel,maxtouch.txt
@@ -0,0 +1,25 @@
+Atmel maXTouch touchscreen/touchpad
+
+Required properties:
+- compatible:
+    atmel,maxtouch
+
+- reg: The I2C address of the device
+
+- interrupts: The sink for the touchpad's IRQ output
+    See ../interrupt-controller/interrupts.txt
+
+Optional properties for main touchpad device:
+
+- linux,gpio-keymap: An array of up to 4 entries indicating the Linux
+    keycode generated by each GPIO. Linux keycodes are defined in
+    <dt-bindings/input/input.h>.
+
+Example:
+
+       touch@4b {
+               compatible = "atmel,maxtouch";
+               reg = <0x4b>;
+               interrupt-parent = <&gpio>;
+               interrupts = <TEGRA_GPIO(W, 3) IRQ_TYPE_LEVEL_LOW>;
+       };

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 31113c3..4317273 100644 (file)
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -22,6 +22,7 @@
 #include <linux/i2c/atmel_mxt_ts.h>
 #include <linux/input/mt.h>
 #include <linux/interrupt.h>
+#include <linux/of.h>
 #include <linux/slab.h>
 
 /* Version */
@@ -1527,15 +1528,65 @@ static void mxt_input_close(struct input_dev *dev)
        mxt_stop(data);
 }
 
-static int mxt_probe(struct i2c_client *client,
-               const struct i2c_device_id *id)
+#ifdef CONFIG_OF
+static struct mxt_platform_data *mxt_parse_dt(struct i2c_client *client)
+{
+       struct mxt_platform_data *pdata;
+       u32 *keymap;
+       u32 keycode;
+       int proplen, i, ret;
+
+       if (!client->dev.of_node)
+               return ERR_PTR(-ENODEV);
+
+       pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
+       if (!pdata)
+               return ERR_PTR(-ENOMEM);
+
+       if (of_find_property(client->dev.of_node, "linux,gpio-keymap",
+                            &proplen)) {
+               pdata->t19_num_keys = proplen / sizeof(u32);
+
+               keymap = devm_kzalloc(&client->dev,
+                               pdata->t19_num_keys * sizeof(keymap[0]),
+                               GFP_KERNEL);
+               if (!keymap)
+                       return ERR_PTR(-ENOMEM);
+
+               for (i = 0; i < pdata->t19_num_keys; i++) {
+                       ret = of_property_read_u32_index(client->dev.of_node,
+                                       "linux,gpio-keymap", i, &keycode);
+                       if (ret)
+                               keycode = KEY_RESERVED;
+
+                       keymap[i] = keycode;
+               }
+
+               pdata->t19_keymap = keymap;
+       }
+
+       return pdata;
+}
+#else
+static struct mxt_platform_data *mxt_parse_dt(struct i2c_client *client)
+{
+       dev_dbg(&client->dev, "No platform data specified\n");
+       return ERR_PTR(-EINVAL);
+}
+#endif
+
+static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id)
 {
        struct mxt_data *data;
-       const struct mxt_platform_data *pdata = dev_get_platdata(&client->dev);
+       const struct mxt_platform_data *pdata;
        int error;
 
-       if (!pdata)
-               return -EINVAL;
+       pdata = dev_get_platdata(&client->dev);
+       if (!pdata) {
+               pdata = mxt_parse_dt(client);
+               if (IS_ERR(pdata))
+                       return PTR_ERR(pdata);
+       }
 
        data = kzalloc(sizeof(struct mxt_data), GFP_KERNEL);
        if (!data) {
@@ -1638,6 +1689,12 @@ static int mxt_resume(struct device *dev)
 
 static SIMPLE_DEV_PM_OPS(mxt_pm_ops, mxt_suspend, mxt_resume);
 
+static const struct of_device_id mxt_of_match[] = {
+       { .compatible = "atmel,maxtouch", },
+       {},
+};
+MODULE_DEVICE_TABLE(of, mxt_of_match);
+
 static const struct i2c_device_id mxt_id[] = {
        { "qt602240_ts", 0 },
        { "atmel_mxt_ts", 0 },
@@ -1651,6 +1708,7 @@ static struct i2c_driver mxt_driver = {
        .driver = {
                .name   = "atmel_mxt_ts",
                .owner  = THIS_MODULE,
+               .of_match_table = of_match_ptr(mxt_of_match),
                .pm     = &mxt_pm_ops,
        },
        .probe          = mxt_probe,