Commit bdc511f4 authored by Jean Delvare's avatar Jean Delvare Committed by Jean Delvare
Browse files

i2c: Use the driver model reference counting 



Don't implement our own reference counting mechanism for i2c clients
when the driver model already has one.

Signed-off-by: default avatarJean Delvare <khali@linux-fr.org>
Cc: David Brownell <david-b@pacbell.net>
parent 0f79b72e

drivers/i2c/i2c-core.c

+2 −44
Original line number Diff line number Diff line
@@ -696,8 +696,6 @@ int i2c_attach_client(struct i2c_client *client) 
	}

	list_add_tail(&client->list,&adapter->clients);



	client->usage_count = 0;



	client->dev.parent = &client->adapter->dev;

	client->dev.bus = &i2c_bus_type;
@@ -744,12 +742,6 @@ int i2c_detach_client(struct i2c_client *client) 
	struct i2c_adapter *adapter = client->adapter;

	int res = 0;



	if (client->usage_count > 0) {

		dev_warn(&client->dev, "Client [%s] still busy, "

			 "can't detach\n", client->name);

		return -EBUSY;

	}



	if (adapter->client_unregister)  {

		res = adapter->client_unregister(client);

		if (res) {
@@ -772,50 +764,16 @@ int i2c_detach_client(struct i2c_client *client) 
}

EXPORT_SYMBOL(i2c_detach_client);



static int i2c_inc_use_client(struct i2c_client *client)

{



	if (!try_module_get(client->driver->driver.owner))

		return -ENODEV;

	if (!try_module_get(client->adapter->owner)) {

		module_put(client->driver->driver.owner);

		return -ENODEV;

	}



	return 0;

}



static void i2c_dec_use_client(struct i2c_client *client)

{

	module_put(client->driver->driver.owner);

	module_put(client->adapter->owner);

}



int i2c_use_client(struct i2c_client *client)

{

	int ret;



	ret = i2c_inc_use_client(client);

	if (ret)

		return ret;



	client->usage_count++;



	get_device(&client->dev);

	return 0;

}

EXPORT_SYMBOL(i2c_use_client);



int i2c_release_client(struct i2c_client *client)

{

	if (!client->usage_count) {

		pr_debug("i2c-core: %s used one too many times\n",

			 __FUNCTION__);

		return -EPERM;

	}



	client->usage_count--;

	i2c_dec_use_client(client);



	put_device(&client->dev);

	return 0;

}

EXPORT_SYMBOL(i2c_release_client);

drivers/media/video/ks0127.c

+0 −1
Original line number Diff line number Diff line
@@ -764,7 +764,6 @@ static struct i2c_client ks0127_client_tmpl = 
	.addr = 0,

	.adapter = NULL,

	.driver = &i2c_driver_ks0127,

	.usage_count = 0

};



static int ks0127_found_proc(struct i2c_adapter *adapter, int addr, int kind)

include/linux/i2c.h

+0 −3
Original line number Diff line number Diff line
@@ -155,7 +155,6 @@ struct i2c_driver { 
 *	generic enough to hide second-sourcing and compatible revisions.

 * @adapter: manages the bus segment hosting this I2C device

 * @driver: device's driver, hence pointer to access routines

 * @usage_count: counts current number of users of this client

 * @dev: Driver model device node for the slave.

 * @irq: indicates the IRQ generated by this device (if any)

 * @driver_name: Identifies new-style driver used with this device; also
@@ -175,8 +174,6 @@ struct i2c_client { 
	char name[I2C_NAME_SIZE];

	struct i2c_adapter *adapter;	/* the adapter we sit on	*/

	struct i2c_driver *driver;	/* and our access routines	*/

	int usage_count;		/* How many accesses currently  */

					/* to the client		*/

	struct device dev;		/* the device structure		*/

	int irq;			/* irq issued by device (or -1) */

	char driver_name[KOBJ_NAME_LEN];