i2c: Add support for device alias names
Based on earlier work by Jon Smirl and Jochen Friedrich.
This patch allows new-style i2c chip drivers to have alias names using
the official kernel aliasing system and MODULE_DEVICE_TABLE(). At this
point, the old i2c driver binding scheme (driver_name/type) is still
supported.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Jochen Friedrich <jochen@scram.de>
Cc: Jon Smirl <jonsmirl@gmail.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 6c7fa8d..26384da 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -48,6 +48,17 @@
/* ------------------------------------------------------------------------- */
+static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id,
+ const struct i2c_client *client)
+{
+ while (id->name[0]) {
+ if (strcmp(client->name, id->name) == 0)
+ return id;
+ id++;
+ }
+ return NULL;
+}
+
static int i2c_device_match(struct device *dev, struct device_driver *drv)
{
struct i2c_client *client = to_i2c_client(dev);
@@ -59,6 +70,10 @@
if (!is_newstyle_driver(driver))
return 0;
+ /* match on an id table if there is one */
+ if (driver->id_table)
+ return i2c_match_id(driver->id_table, client) != NULL;
+
/* new style drivers use the same kind of driver matching policy
* as platform devices or SPI: compare device and driver IDs.
*/
@@ -73,11 +88,17 @@
struct i2c_client *client = to_i2c_client(dev);
/* by definition, legacy drivers can't hotplug */
- if (dev->driver || !client->driver_name)
+ if (dev->driver)
return 0;
- if (add_uevent_var(env, "MODALIAS=%s", client->driver_name))
- return -ENOMEM;
+ if (client->driver_name[0]) {
+ if (add_uevent_var(env, "MODALIAS=%s", client->driver_name))
+ return -ENOMEM;
+ } else {
+ if (add_uevent_var(env, "MODALIAS=%s%s",
+ I2C_MODULE_PREFIX, client->name))
+ return -ENOMEM;
+ }
dev_dbg(dev, "uevent\n");
return 0;
}
@@ -90,13 +111,19 @@
{
struct i2c_client *client = to_i2c_client(dev);
struct i2c_driver *driver = to_i2c_driver(dev->driver);
+ const struct i2c_device_id *id;
int status;
if (!driver->probe)
return -ENODEV;
client->driver = driver;
dev_dbg(dev, "probe\n");
- status = driver->probe(client);
+
+ if (driver->id_table)
+ id = i2c_match_id(driver->id_table, client);
+ else
+ id = NULL;
+ status = driver->probe(client, id);
if (status)
client->driver = NULL;
return status;
@@ -179,9 +206,9 @@
static ssize_t show_modalias(struct device *dev, struct device_attribute *attr, char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
- return client->driver_name
+ return client->driver_name[0]
? sprintf(buf, "%s\n", client->driver_name)
- : 0;
+ : sprintf(buf, "%s%s\n", I2C_MODULE_PREFIX, client->name);
}
static struct device_attribute i2c_dev_attrs[] = {
@@ -300,15 +327,21 @@
EXPORT_SYMBOL_GPL(i2c_unregister_device);
-static int dummy_nop(struct i2c_client *client)
+static int dummy_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ return 0;
+}
+
+static int dummy_remove(struct i2c_client *client)
{
return 0;
}
static struct i2c_driver dummy_driver = {
.driver.name = "dummy",
- .probe = dummy_nop,
- .remove = dummy_nop,
+ .probe = dummy_probe,
+ .remove = dummy_remove,
};
/**