From 8ffbc6559493c64d6194c92d856196fdaeb8a5fb Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Wed, 12 Sep 2007 08:32:50 -0300 Subject: [PATCH] V4L/DVB (6451): v4l2: add support for bus-based I2C drivers Two new headers were added: one for I2C drivers that are only used by V4L2 drivers converted to the new bus-based I2C API, and one that can be used by both converted and unconverted drivers (at the expense of some additional overhead). To support the legacy I2C API a helper function was added to v4l2-common.c. These headers take care of all the 'boilerplate' code that all V4L2 I2C drivers have in common and will automatically support the bus-based I2C API introduced in kernel 2.6.22. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/v4l2-common.c | 31 +++++++ include/media/v4l2-common.h | 11 +++ include/media/v4l2-i2c-drv-legacy.h | 132 ++++++++++++++++++++++++++++ include/media/v4l2-i2c-drv.h | 61 +++++++++++++ 4 files changed, 235 insertions(+) create mode 100644 include/media/v4l2-i2c-drv-legacy.h create mode 100644 include/media/v4l2-i2c-drv.h diff --git a/drivers/media/video/v4l2-common.c b/drivers/media/video/v4l2-common.c index a4d68d3ba5e4..32607a612b18 100644 --- a/drivers/media/video/v4l2-common.c +++ b/drivers/media/video/v4l2-common.c @@ -1013,6 +1013,35 @@ int v4l2_chip_match_host(u32 match_type, u32 match_chip) /* ----------------------------------------------------------------- */ +/* Helper function for I2C legacy drivers */ + +int v4l2_i2c_attach(struct i2c_adapter *adapter, int address, struct i2c_driver *driver, + const char *name, int (*probe)(struct i2c_client *)) +{ + struct i2c_client *client; + int err; + + client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL); + if (client == 0) + return -ENOMEM; + + client->addr = address; + client->adapter = adapter; + client->driver = driver; + snprintf(client->name, sizeof(client->name) - 1, name); + + err = probe(client); + if (err == 0) { + i2c_attach_client(client); + } + else { + kfree(client); + } + return err; +} + +/* ----------------------------------------------------------------- */ + EXPORT_SYMBOL(v4l2_norm_to_name); EXPORT_SYMBOL(v4l2_video_std_construct); @@ -1038,6 +1067,8 @@ EXPORT_SYMBOL(v4l2_chip_match_i2c_client); EXPORT_SYMBOL(v4l2_chip_ident_i2c_client); EXPORT_SYMBOL(v4l2_chip_match_host); +EXPORT_SYMBOL(v4l2_i2c_attach); + /* * Local variables: * c-basic-offset: 8 diff --git a/include/media/v4l2-common.h b/include/media/v4l2-common.h index c019c1e99895..475d0d8275e0 100644 --- a/include/media/v4l2-common.h +++ b/include/media/v4l2-common.h @@ -104,6 +104,17 @@ int v4l2_chip_match_host(u32 id_type, u32 chip_id); /* ------------------------------------------------------------------------- */ +/* Helper function for I2C legacy drivers */ + +struct i2c_driver; +struct i2c_adapter; +struct i2c_client; + +int v4l2_i2c_attach(struct i2c_adapter *adapter, int address, struct i2c_driver *driver, + const char *name, int (*probe)(struct i2c_client *)); + +/* ------------------------------------------------------------------------- */ + /* Internal ioctls */ /* VIDIOC_INT_DECODE_VBI_LINE */ diff --git a/include/media/v4l2-i2c-drv-legacy.h b/include/media/v4l2-i2c-drv-legacy.h new file mode 100644 index 000000000000..c059b32844c1 --- /dev/null +++ b/include/media/v4l2-i2c-drv-legacy.h @@ -0,0 +1,132 @@ +/* + * v4l2-i2c-drv-legacy.h - contains I2C handling code that's identical + * for all V4L2 I2C drivers. Use this header if the + * I2C driver is used by both legacy drivers and + * drivers converted to the bus-based I2C API. + * + * Copyright (C) 2007 Hans Verkuil + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +struct v4l2_i2c_driver_data { + const char * const name; + int driverid; + int (*command)(struct i2c_client *client, unsigned int cmd, void *arg); + int (*probe)(struct i2c_client *client); + int (*remove)(struct i2c_client *client); + int (*suspend)(struct i2c_client *client, pm_message_t state); + int (*resume)(struct i2c_client *client); + int legacy_class; +}; + +static struct v4l2_i2c_driver_data v4l2_i2c_data; +static struct i2c_client_address_data addr_data; +static struct i2c_driver v4l2_i2c_driver_legacy; +static char v4l2_i2c_drv_name_legacy[32]; + +static int v4l2_i2c_drv_attach_legacy(struct i2c_adapter *adapter, int address, int kind) +{ + return v4l2_i2c_attach(adapter, address, &v4l2_i2c_driver_legacy, + v4l2_i2c_drv_name_legacy, v4l2_i2c_data.probe); +} + +static int v4l2_i2c_drv_probe_legacy(struct i2c_adapter *adapter) +{ + if (adapter->class & v4l2_i2c_data.legacy_class) + return i2c_probe(adapter, &addr_data, v4l2_i2c_drv_attach_legacy); + return 0; +} + +static int v4l2_i2c_drv_detach_legacy(struct i2c_client *client) +{ + int err = i2c_detach_client(client); + + if (err) + return err; + if (v4l2_i2c_data.remove) + v4l2_i2c_data.remove(client); + kfree(client); + + return 0; +} + +static int v4l2_i2c_drv_suspend_helper(struct i2c_client *client, pm_message_t state) +{ + return v4l2_i2c_data.suspend ? v4l2_i2c_data.suspend(client, state) : 0; +} + +static int v4l2_i2c_drv_resume_helper(struct i2c_client *client) +{ + return v4l2_i2c_data.resume ? v4l2_i2c_data.resume(client) : 0; +} + +/* ----------------------------------------------------------------------- */ + +/* i2c implementation */ +static struct i2c_driver v4l2_i2c_driver_legacy = { + .driver = { + .owner = THIS_MODULE, + }, + .attach_adapter = v4l2_i2c_drv_probe_legacy, + .detach_client = v4l2_i2c_drv_detach_legacy, + .suspend = v4l2_i2c_drv_suspend_helper, + .resume = v4l2_i2c_drv_resume_helper, +}; + +/* ----------------------------------------------------------------------- */ + +/* i2c implementation */ +static struct i2c_driver v4l2_i2c_driver = { + .suspend = v4l2_i2c_drv_suspend_helper, + .resume = v4l2_i2c_drv_resume_helper, +}; + +static int __init v4l2_i2c_drv_init(void) +{ + int err; + + strlcpy(v4l2_i2c_drv_name_legacy, v4l2_i2c_data.name, sizeof(v4l2_i2c_drv_name_legacy)); + strlcat(v4l2_i2c_drv_name_legacy, "'", sizeof(v4l2_i2c_drv_name_legacy)); + + if (v4l2_i2c_data.legacy_class == 0) + v4l2_i2c_data.legacy_class = I2C_CLASS_TV_ANALOG; + + v4l2_i2c_driver_legacy.driver.name = v4l2_i2c_drv_name_legacy; + v4l2_i2c_driver_legacy.id = v4l2_i2c_data.driverid; + v4l2_i2c_driver_legacy.command = v4l2_i2c_data.command; + err = i2c_add_driver(&v4l2_i2c_driver_legacy); + + if (err) + return err; + v4l2_i2c_driver.driver.name = v4l2_i2c_data.name; + v4l2_i2c_driver.id = v4l2_i2c_data.driverid; + v4l2_i2c_driver.command = v4l2_i2c_data.command; + v4l2_i2c_driver.probe = v4l2_i2c_data.probe; + v4l2_i2c_driver.remove = v4l2_i2c_data.remove; + err = i2c_add_driver(&v4l2_i2c_driver); + if (err) + i2c_del_driver(&v4l2_i2c_driver_legacy); + return err; +} + +static void __exit v4l2_i2c_drv_cleanup(void) +{ + i2c_del_driver(&v4l2_i2c_driver_legacy); + i2c_del_driver(&v4l2_i2c_driver); +} + +module_init(v4l2_i2c_drv_init); +module_exit(v4l2_i2c_drv_cleanup); diff --git a/include/media/v4l2-i2c-drv.h b/include/media/v4l2-i2c-drv.h new file mode 100644 index 000000000000..547db60d3640 --- /dev/null +++ b/include/media/v4l2-i2c-drv.h @@ -0,0 +1,61 @@ +/* + * v4l2-i2c-drv.h - contains I2C handling code that's identical for + * all V4L2 I2C drivers. Use this header if the + * I2C driver is only used by drivers converted + * to the bus-based I2C API. + * + * Copyright (C) 2007 Hans Verkuil + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +struct v4l2_i2c_driver_data { + const char * const name; + int driverid; + int (*command)(struct i2c_client *client, unsigned int cmd, void *arg); + int (*probe)(struct i2c_client *client); + int (*remove)(struct i2c_client *client); + int (*suspend)(struct i2c_client *client, pm_message_t state); + int (*resume)(struct i2c_client *client); + int legacy_class; +}; + +static struct v4l2_i2c_driver_data v4l2_i2c_data; +static struct i2c_client_address_data addr_data; +static struct i2c_driver v4l2_i2c_driver; + + +/* Bus-based I2C implementation for kernels >= 2.6.22 */ + +static int __init v4l2_i2c_drv_init(void) +{ + v4l2_i2c_driver.driver.name = v4l2_i2c_data.name; + v4l2_i2c_driver.id = v4l2_i2c_data.driverid; + v4l2_i2c_driver.command = v4l2_i2c_data.command; + v4l2_i2c_driver.probe = v4l2_i2c_data.probe; + v4l2_i2c_driver.remove = v4l2_i2c_data.remove; + v4l2_i2c_driver.suspend = v4l2_i2c_data.suspend; + v4l2_i2c_driver.resume = v4l2_i2c_data.resume; + return i2c_add_driver(&v4l2_i2c_driver); +} + + +static void __exit v4l2_i2c_drv_cleanup(void) +{ + i2c_del_driver(&v4l2_i2c_driver); +} + +module_init(v4l2_i2c_drv_init); +module_exit(v4l2_i2c_drv_cleanup);