HID: i2c-hid: add DT bindings
Add device tree based support for HID over I2C devices.
Tested on an Odroid-X board with a Synaptics touchpad.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c
index 879b0ed..fc9d92c 100644
--- a/drivers/hid/i2c-hid/i2c-hid.c
+++ b/drivers/hid/i2c-hid/i2c-hid.c
@@ -35,6 +35,7 @@
#include <linux/hid.h>
#include <linux/mutex.h>
#include <linux/acpi.h>
+#include <linux/of.h>
#include <linux/i2c/i2c-hid.h>
@@ -933,6 +934,42 @@
}
#endif
+#ifdef CONFIG_OF
+static int i2c_hid_of_probe(struct i2c_client *client,
+ struct i2c_hid_platform_data *pdata)
+{
+ struct device *dev = &client->dev;
+ u32 val;
+ int ret;
+
+ ret = of_property_read_u32(dev->of_node, "hid-descr-addr", &val);
+ if (ret) {
+ dev_err(&client->dev, "HID register address not provided\n");
+ return -ENODEV;
+ }
+ if (val >> 16) {
+ dev_err(&client->dev, "Bad HID register address: 0x%08x\n",
+ val);
+ return -EINVAL;
+ }
+ pdata->hid_descriptor_address = val;
+
+ return 0;
+}
+
+static const struct of_device_id i2c_hid_of_match[] = {
+ { .compatible = "hid-over-i2c" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, i2c_hid_of_match);
+#else
+static inline int i2c_hid_of_probe(struct i2c_client *client,
+ struct i2c_hid_platform_data *pdata)
+{
+ return -ENODEV;
+}
+#endif
+
static int i2c_hid_probe(struct i2c_client *client,
const struct i2c_device_id *dev_id)
{
@@ -954,7 +991,11 @@
if (!ihid)
return -ENOMEM;
- if (!platform_data) {
+ if (client->dev.of_node) {
+ ret = i2c_hid_of_probe(client, &ihid->pdata);
+ if (ret)
+ goto err;
+ } else if (!platform_data) {
ret = i2c_hid_acpi_pdata(client, &ihid->pdata);
if (ret) {
dev_err(&client->dev,
@@ -1095,6 +1136,7 @@
.owner = THIS_MODULE,
.pm = &i2c_hid_pm,
.acpi_match_table = ACPI_PTR(i2c_hid_acpi_match),
+ .of_match_table = of_match_ptr(i2c_hid_of_match),
},
.probe = i2c_hid_probe,