From dd99120c7165c6873a423977d1eaa41b6e2d1ffc Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Sun, 23 Nov 2008 12:19:45 -0300 Subject: V4L/DVB (9821): v4l2-common: add i2c helper functions Add helper functions to load i2c sub-devices, integrating them into the v4l2-framework. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/v4l2-common.c | 113 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 113 insertions(+) (limited to 'drivers/media/video/v4l2-common.c') diff --git a/drivers/media/video/v4l2-common.c b/drivers/media/video/v4l2-common.c index fdc8871f631..26f3254337d 100644 --- a/drivers/media/video/v4l2-common.c +++ b/drivers/media/video/v4l2-common.c @@ -58,6 +58,7 @@ #include #define __OLD_VIDIOC_ /* To allow fixing old calls*/ #include +#include #include #include @@ -801,4 +802,116 @@ int v4l2_i2c_attach(struct i2c_adapter *adapter, int address, struct i2c_driver return err != -ENOMEM ? 0 : err; } EXPORT_SYMBOL(v4l2_i2c_attach); + +void v4l2_i2c_subdev_init(struct v4l2_subdev *sd, struct i2c_client *client, + const struct v4l2_subdev_ops *ops) +{ + v4l2_subdev_init(sd, ops); + /* the owner is the same as the i2c_client's driver owner */ + sd->owner = client->driver->driver.owner; + /* i2c_client and v4l2_subdev point to one another */ + v4l2_set_subdevdata(sd, client); + i2c_set_clientdata(client, sd); + /* initialize name */ + snprintf(sd->name, sizeof(sd->name), "%s %d-%04x", + client->driver->driver.name, i2c_adapter_id(client->adapter), + client->addr); +} +EXPORT_SYMBOL_GPL(v4l2_i2c_subdev_init); + + + +/* Load an i2c sub-device. It assumes that i2c_get_adapdata(adapter) + returns the v4l2_device and that i2c_get_clientdata(client) + returns the v4l2_subdev. */ +struct v4l2_subdev *v4l2_i2c_new_subdev(struct i2c_adapter *adapter, + const char *module_name, const char *client_type, u8 addr) +{ + struct v4l2_device *dev = i2c_get_adapdata(adapter); + struct v4l2_subdev *sd = NULL; + struct i2c_client *client; + struct i2c_board_info info; + + BUG_ON(!dev); +#ifdef MODULE + if (module_name) + request_module(module_name); +#endif + /* Setup the i2c board info with the device type and + the device address. */ + memset(&info, 0, sizeof(info)); + strlcpy(info.type, client_type, sizeof(info.type)); + info.addr = addr; + + /* Create the i2c client */ + client = i2c_new_device(adapter, &info); + /* Note: it is possible in the future that + c->driver is NULL if the driver is still being loaded. + We need better support from the kernel so that we + can easily wait for the load to finish. */ + if (client == NULL || client->driver == NULL) + return NULL; + + /* Lock the module so we can safely get the v4l2_subdev pointer */ + if (!try_module_get(client->driver->driver.owner)) + return NULL; + sd = i2c_get_clientdata(client); + + /* Register with the v4l2_device which increases the module's + use count as well. */ + if (v4l2_device_register_subdev(dev, sd)) + sd = NULL; + /* Decrease the module use count to match the first try_module_get. */ + module_put(client->driver->driver.owner); + return sd; + +} +EXPORT_SYMBOL_GPL(v4l2_i2c_new_subdev); + +/* Probe and load an i2c sub-device. It assumes that i2c_get_adapdata(adapter) + returns the v4l2_device and that i2c_get_clientdata(client) + returns the v4l2_subdev. */ +struct v4l2_subdev *v4l2_i2c_new_probed_subdev(struct i2c_adapter *adapter, + const char *module_name, const char *client_type, + const unsigned short *addrs) +{ + struct v4l2_device *dev = i2c_get_adapdata(adapter); + struct v4l2_subdev *sd = NULL; + struct i2c_client *client = NULL; + struct i2c_board_info info; + + BUG_ON(!dev); +#ifdef MODULE + if (module_name) + request_module(module_name); +#endif + /* Setup the i2c board info with the device type and + the device address. */ + memset(&info, 0, sizeof(info)); + strlcpy(info.type, client_type, sizeof(info.type)); + + /* Probe and create the i2c client */ + client = i2c_new_probed_device(adapter, &info, addrs); + /* Note: it is possible in the future that + c->driver is NULL if the driver is still being loaded. + We need better support from the kernel so that we + can easily wait for the load to finish. */ + if (client == NULL || client->driver == NULL) + return NULL; + + /* Lock the module so we can safely get the v4l2_subdev pointer */ + if (!try_module_get(client->driver->driver.owner)) + return NULL; + sd = i2c_get_clientdata(client); + + /* Register with the v4l2_device which increases the module's + use count as well. */ + if (v4l2_device_register_subdev(dev, sd)) + sd = NULL; + /* Decrease the module use count to match the first try_module_get. */ + module_put(client->driver->driver.owner); + return sd; +} +EXPORT_SYMBOL_GPL(v4l2_i2c_new_probed_subdev); + #endif -- cgit v1.2.3