Publicly expose functions for detecting devices and removing detected devices. Currently an i2c adapter only probes/detects new devices when the adapter is added or when a new i2c driver is added. This adds a new function, i2c_adapter_probe(), that allows detecting sensors at any time. Furthermore, the function i2c_adapter_remove_probed() is added to remove the devices added by i2c_adapter_probe() at any time. The intended use of these functions is for LEGO MINDSTORMS sensors. These are hot-plugable I2C devices. When a sensor is connected, i2c_adapter_probe() is called to automatically configure the sensor. When the sensor is disconnected, i2c_adapter_remove_probed() is called to remove the automatically configured device. Signed-off-by: David Lechner <david@xxxxxxxxxxxxxx> --- drivers/i2c/i2c-core.c | 45 ++++++++++++++++++++++++++++++++++++++------- include/linux/i2c.h | 3 +++ 2 files changed, 41 insertions(+), 7 deletions(-) diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index 28436d9..2781a88 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -1691,6 +1691,23 @@ static int __process_new_adapter(struct device_driver *d, void *data) return i2c_do_add_adapter(to_i2c_driver(d), data); } +/** + * i2c_adapter_probe - probe adapter for clients + * @adap: The i2c adapter. + * + * This calls the detect function of each driver that matches the class of the + * adapter. This function is called when an adapter is added, so there is no + * need to call this manually, unless you have hot-plugable i2c devices that + * are connected after the adapter is created. + */ +void i2c_adapter_probe(struct i2c_adapter *adap) +{ + mutex_lock(&core_lock); + bus_for_each_drv(&i2c_bus_type, NULL, adap, __process_new_adapter); + mutex_unlock(&core_lock); +} +EXPORT_SYMBOL(i2c_adapter_probe); + static int i2c_register_adapter(struct i2c_adapter *adap) { int res = -EINVAL; @@ -1759,9 +1776,7 @@ static int i2c_register_adapter(struct i2c_adapter *adap) i2c_scan_static_board_info(adap); /* Notify drivers */ - mutex_lock(&core_lock); - bus_for_each_drv(&i2c_bus_type, NULL, adap, __process_new_adapter); - mutex_unlock(&core_lock); + i2c_adapter_probe(adap); return 0; @@ -1904,6 +1919,25 @@ static int __process_removed_adapter(struct device_driver *d, void *data) } /** + * i2c_adapter_remove_probed - Remove clients that were automatically detected. + * @adap: The i2c adapter. + * + * This removes all i2c clients from this adapter that were added via driver + * detect() functions. This function is called when an adapter is removed, so + * there is no need to call this manually, unless you have hot-plugable i2c + * devices that are disconnected before the adapter is destroyed. + * + * Any clients that were added manually (e.g. via sysfs) are not removed. + */ +void i2c_adapter_remove_probed(struct i2c_adapter *adap) +{ + mutex_lock(&core_lock); + bus_for_each_drv(&i2c_bus_type, NULL, adap, __process_removed_adapter); + mutex_unlock(&core_lock); +} +EXPORT_SYMBOL(i2c_adapter_remove_probed); + +/** * i2c_del_adapter - unregister I2C adapter * @adap: the adapter being unregistered * Context: can sleep @@ -1927,10 +1961,7 @@ void i2c_del_adapter(struct i2c_adapter *adap) acpi_i2c_remove_space_handler(adap); /* Tell drivers about this removal */ - mutex_lock(&core_lock); - bus_for_each_drv(&i2c_bus_type, NULL, adap, - __process_removed_adapter); - mutex_unlock(&core_lock); + i2c_adapter_remove_probed(adap); /* Remove devices instantiated from sysfs */ mutex_lock_nested(&adap->userspace_clients_lock, diff --git a/include/linux/i2c.h b/include/linux/i2c.h index 3eab858..0016623 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -657,6 +657,9 @@ extern int i2c_add_adapter(struct i2c_adapter *); extern void i2c_del_adapter(struct i2c_adapter *); extern int i2c_add_numbered_adapter(struct i2c_adapter *); +extern void i2c_adapter_probe(struct i2c_adapter *adap); +extern void i2c_adapter_remove_probed(struct i2c_adapter *adap); + extern int i2c_register_driver(struct module *, struct i2c_driver *); extern void i2c_del_driver(struct i2c_driver *); -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html