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>

1 files changed, 63 insertions, 5 deletions

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 31113c372f59..4317273c2138 100644
--- 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,