/* * 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);