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 <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
This commit is contained in:
Hans Verkuil 2007-09-12 08:32:50 -03:00 committed by Mauro Carvalho Chehab
parent 5ef4730d1b
commit 8ffbc65594
4 changed files with 235 additions and 0 deletions

View File

@ -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

View File

@ -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 */

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@ -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 <hverkuil@xs4all.nl>
*
* 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);

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@ -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 <hverkuil@xs4all.nl>
*
* 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);