i2c: i2c stack can remove() (a1d9e6e4) · Commits · 戴 / test

drivers/i2c/i2c-core.c

+61 −4

Original line number	Diff line number	Diff line
		@@ -41,6 +41,7 @@ static LIST_HEAD(drivers);
		static DEFINE_MUTEX(core_lists);
		static DEFINE_IDR(i2c_adapter_idr);

		#define is_newstyle_driver(d) ((d)->probe \|\| (d)->remove)

		/* ------------------------------------------------------------------------- */

		@@ -52,7 +53,7 @@ static int i2c_device_match(struct device dev, struct device_driver drv)
		/* make legacy i2c drivers bypass driver model probing entirely;
		* such drivers scan each i2c adapter/bus themselves.
		*/
		if (!driver->probe)
		if (!is_newstyle_driver(driver))
		return 0;

		/* new style drivers use the same kind of driver matching policy
		@@ -100,7 +101,24 @@ static int i2c_device_probe(struct device *dev)

		static int i2c_device_remove(struct device *dev)
		{
		struct i2c_client *client = to_i2c_client(dev);
		struct i2c_driver *driver;
		int status;

		if (!dev->driver)
		return 0;

		driver = to_i2c_driver(dev->driver);
		if (driver->remove) {
		dev_dbg(dev, "remove\n");
		status = driver->remove(client);
		} else {
		dev->driver = NULL;
		status = 0;
		}
		if (status == 0)
		client->driver = NULL;
		return status;
		}

		static void i2c_device_shutdown(struct device *dev)
		@@ -177,6 +195,26 @@ struct bus_type i2c_bus_type = {
		.resume = i2c_device_resume,
		};

		static void i2c_unregister_device(struct i2c_client *client)
		{
		struct i2c_adapter *adapter = client->adapter;
		struct i2c_driver *driver = client->driver;

		if (driver && !is_newstyle_driver(driver)) {
		dev_err(&client->dev, "can't unregister devices "
		"with legacy drivers\n");
		WARN_ON(1);
		return;
		}

		mutex_lock(&adapter->clist_lock);
		list_del(&client->list);
		mutex_unlock(&adapter->clist_lock);

		device_unregister(&client->dev);
		}


		/* ------------------------------------------------------------------------- */

		/* I2C bus adapters -- one roots each I2C or SMBUS segment */
		@@ -310,9 +348,19 @@ int i2c_del_adapter(struct i2c_adapter *adap)
		/* detach any active clients. This must be done first, because
		* it can fail; in which case we give up. */
		list_for_each_safe(item, _n, &adap->clients) {
		struct i2c_driver *driver;

		client = list_entry(item, struct i2c_client, list);
		driver = client->driver;

		/* new style, follow standard driver model */
		if (!driver \|\| is_newstyle_driver(driver)) {
		i2c_unregister_device(client);
		continue;
		}

		if ((res=client->driver->detach_client(client))) {
		/* legacy drivers create and remove clients themselves */
		if ((res = driver->detach_client(client))) {
		dev_err(&adap->dev, "detach_client failed for client "
		"[%s] at address 0x%02x\n", client->name,
		client->addr);
		@@ -355,7 +403,7 @@ int i2c_register_driver(struct module owner, struct i2c_driver driver)
		int res;

		/* new style driver methods can't mix with legacy ones */
		if (driver->probe) {
		if (is_newstyle_driver(driver)) {
		if (driver->attach_adapter \|\| driver->detach_adapter
		\|\| driver->detach_client) {
		printk(KERN_WARNING
		@@ -392,6 +440,10 @@ int i2c_register_driver(struct module owner, struct i2c_driver driver)
		}
		EXPORT_SYMBOL(i2c_register_driver);

		/**
		* i2c_del_driver - unregister I2C driver
		* @driver: the driver being unregistered
		*/
		int i2c_del_driver(struct i2c_driver *driver)
		{
		struct list_head item1, item2, *_n;
		@@ -402,6 +454,10 @@ int i2c_del_driver(struct i2c_driver *driver)

		mutex_lock(&core_lists);

		/* new-style driver? */
		if (is_newstyle_driver(driver))
		goto unregister;

		/* Have a look at each adapter, if clients of this driver are still
		* attached. If so, detach them to be able to kill the driver
		* afterwards.
		@@ -434,6 +490,7 @@ int i2c_del_driver(struct i2c_driver *driver)
		}
		}

		unregister:
		driver_unregister(&driver->driver);
		list_del(&driver->list);
		pr_debug("i2c-core: driver [%s] unregistered\n", driver->driver.name);

include/linux/i2c.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -130,6 +130,7 @@ struct i2c_driver {
		* it's done by infrastructure. (NEW STYLE DRIVERS ONLY)
		*/
		int (probe)(struct i2c_client );
		int (remove)(struct i2c_client );

		/* driver model interfaces that don't relate to enumeration */
		void (shutdown)(struct i2c_client );

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