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/*
* Copyright (C) 2009 Francisco Jerez.
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial
* portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
*/
#include <linux/module.h>
#include "drm_encoder_slave.h"
/**
* drm_i2c_encoder_init - Initialize an I2C slave encoder
* @dev: DRM device.
* @encoder: Encoder to be attached to the I2C device. You aren't
* required to have called drm_encoder_init() before.
* @adap: I2C adapter that will be used to communicate with
* the device.
* @info: Information that will be used to create the I2C device.
* Required fields are @addr and @type.
*
* Create an I2C device on the specified bus (the module containing its
* driver is transparently loaded) and attach it to the specified
* &drm_encoder_slave. The @slave_funcs field will be initialized with
* the hooks provided by the slave driver.
*
* If @info->platform_data is non-NULL it will be used as the initial
* slave config.
*
* Returns 0 on success or a negative errno on failure, in particular,
* -ENODEV is returned when no matching driver is found.
*/
int drm_i2c_encoder_init(struct drm_device *dev,
struct drm_encoder_slave *encoder,
struct i2c_adapter *adap,
const struct i2c_board_info *info)
{
char modalias[sizeof(I2C_MODULE_PREFIX)
+ I2C_NAME_SIZE];
struct module *module = NULL;
struct i2c_client *client;
struct drm_i2c_encoder_driver *encoder_drv;
int err = 0;
snprintf(modalias, sizeof(modalias),
"%s%s", I2C_MODULE_PREFIX, info->type);
request_module(modalias);
client = i2c_new_device(adap, info);
if (!client) {
err = -ENOMEM;
goto fail;
}
if (!client->driver) {
err = -ENODEV;
goto fail_unregister;
}
module = client->driver->driver.owner;
if (!try_module_get(module)) {
err = -ENODEV;
goto fail_unregister;
}
encoder->bus_priv = client;
encoder_drv = to_drm_i2c_encoder_driver(client->driver);
err = encoder_drv->encoder_init(client, dev, encoder);
if (err)
goto fail_unregister;
if (info->platform_data)
encoder->slave_funcs->set_config(&encoder->base,
info->platform_data);
return 0;
fail_unregister:
i2c_unregister_device(client);
module_put(module);
fail:
return err;
}
EXPORT_SYMBOL(drm_i2c_encoder_init);
/**
* drm_i2c_encoder_destroy - Unregister the I2C device backing an encoder
* @drm_encoder: Encoder to be unregistered.
*
* This should be called from the @destroy method of an I2C slave
* encoder driver once I2C access is no longer needed.
*/
void drm_i2c_encoder_destroy(struct drm_encoder *drm_encoder)
{
struct drm_encoder_slave *encoder = to_encoder_slave(drm_encoder);
struct i2c_client *client = drm_i2c_encoder_get_client(drm_encoder);
struct module *module = client->driver->driver.owner;
i2c_unregister_device(client);
encoder->bus_priv = NULL;
module_put(module);
}
EXPORT_SYMBOL(drm_i2c_encoder_destroy);
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