LXR linux/drivers/gpu/drm/drm_encoder

   1/*
   2 * Copyright (C) 2009 Francisco Jerez.
   3 * All Rights Reserved.
   4 *
   5 * Permission is hereby granted, free of charge, to any person obtaining
   6 * a copy of this software and associated documentation files (the
   7 * "Software"), to deal in the Software without restriction, including
   8 * without limitation the rights to use, copy, modify, merge, publish,
   9 * distribute, sublicense, and/or sell copies of the Software, and to
  10 * permit persons to whom the Software is furnished to do so, subject to
  11 * the following conditions:
  12 *
  13 * The above copyright notice and this permission notice (including the
  14 * next paragraph) shall be included in all copies or substantial
  15 * portions of the Software.
  16 *
  17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  18 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  20 * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
  21 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  22 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  23 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  24 *
  25 */
  26
  27#include <linux/module.h>
  28
  29#include <drm/drm_encoder_slave.h>
  30
  31/**
  32 * drm_i2c_encoder_init - Initialize an I2C slave encoder
  33 * @dev:        DRM device.
  34 * @encoder:    Encoder to be attached to the I2C device. You aren't
  35 *              required to have called drm_encoder_init() before.
  36 * @adap:       I2C adapter that will be used to communicate with
  37 *              the device.
  38 * @info:       Information that will be used to create the I2C device.
  39 *              Required fields are @addr and @type.
  40 *
  41 * Create an I2C device on the specified bus (the module containing its
  42 * driver is transparently loaded) and attach it to the specified
  43 * &drm_encoder_slave. The @slave_funcs field will be initialized with
  44 * the hooks provided by the slave driver.
  45 *
  46 * If @info->platform_data is non-NULL it will be used as the initial
  47 * slave config.
  48 *
  49 * Returns 0 on success or a negative errno on failure, in particular,
  50 * -ENODEV is returned when no matching driver is found.
  51 */
  52int drm_i2c_encoder_init(struct drm_device *dev,
  53                         struct drm_encoder_slave *encoder,
  54                         struct i2c_adapter *adap,
  55                         const struct i2c_board_info *info)
  56{
  57        struct module *module = NULL;
  58        struct i2c_client *client;
  59        struct drm_i2c_encoder_driver *encoder_drv;
  60        int err = 0;
  61
  62        request_module("%s%s", I2C_MODULE_PREFIX, info->type);
  63
  64        client = i2c_new_device(adap, info);
  65        if (!client) {
  66                err = -ENOMEM;
  67                goto fail;
  68        }
  69
  70        if (!client->dev.driver) {
  71                err = -ENODEV;
  72                goto fail_unregister;
  73        }
  74
  75        module = client->dev.driver->owner;
  76        if (!try_module_get(module)) {
  77                err = -ENODEV;
  78                goto fail_unregister;
  79        }
  80
  81        encoder->bus_priv = client;
  82
  83        encoder_drv = to_drm_i2c_encoder_driver(to_i2c_driver(client->dev.driver));
  84
  85        err = encoder_drv->encoder_init(client, dev, encoder);
  86        if (err)
  87                goto fail_unregister;
  88
  89        if (info->platform_data)
  90                encoder->slave_funcs->set_config(&encoder->base,
  91                                                 info->platform_data);
  92
  93        return 0;
  94
  95fail_unregister:
  96        i2c_unregister_device(client);
  97        module_put(module);
  98fail:
  99        return err;
 100}
 101EXPORT_SYMBOL(drm_i2c_encoder_init);
 102
 103/**
 104 * drm_i2c_encoder_destroy - Unregister the I2C device backing an encoder
 105 * @drm_encoder:        Encoder to be unregistered.
 106 *
 107 * This should be called from the @destroy method of an I2C slave
 108 * encoder driver once I2C access is no longer needed.
 109 */
 110void drm_i2c_encoder_destroy(struct drm_encoder *drm_encoder)
 111{
 112        struct drm_encoder_slave *encoder = to_encoder_slave(drm_encoder);
 113        struct i2c_client *client = drm_i2c_encoder_get_client(drm_encoder);
 114        struct module *module = client->dev.driver->owner;
 115
 116        i2c_unregister_device(client);
 117        encoder->bus_priv = NULL;
 118
 119        module_put(module);
 120}
 121EXPORT_SYMBOL(drm_i2c_encoder_destroy);
 122
 123/*
 124 * Wrapper fxns which can be plugged in to drm_encoder_helper_funcs:
 125 */
 126
 127static inline const struct drm_encoder_slave_funcs *
 128get_slave_funcs(struct drm_encoder *enc)
 129{
 130        return to_encoder_slave(enc)->slave_funcs;
 131}
 132
 133void drm_i2c_encoder_dpms(struct drm_encoder *encoder, int mode)
 134{
 135        get_slave_funcs(encoder)->dpms(encoder, mode);
 136}
 137EXPORT_SYMBOL(drm_i2c_encoder_dpms);
 138
 139bool drm_i2c_encoder_mode_fixup(struct drm_encoder *encoder,
 140                const struct drm_display_mode *mode,
 141                struct drm_display_mode *adjusted_mode)
 142{
 143        if (!get_slave_funcs(encoder)->mode_fixup)
 144                return true;
 145
 146        return get_slave_funcs(encoder)->mode_fixup(encoder, mode, adjusted_mode);
 147}
 148EXPORT_SYMBOL(drm_i2c_encoder_mode_fixup);
 149
 150void drm_i2c_encoder_prepare(struct drm_encoder *encoder)
 151{
 152        drm_i2c_encoder_dpms(encoder, DRM_MODE_DPMS_OFF);
 153}
 154EXPORT_SYMBOL(drm_i2c_encoder_prepare);
 155
 156void drm_i2c_encoder_commit(struct drm_encoder *encoder)
 157{
 158        drm_i2c_encoder_dpms(encoder, DRM_MODE_DPMS_ON);
 159}
 160EXPORT_SYMBOL(drm_i2c_encoder_commit);
 161
 162void drm_i2c_encoder_mode_set(struct drm_encoder *encoder,
 163                struct drm_display_mode *mode,
 164                struct drm_display_mode *adjusted_mode)
 165{
 166        get_slave_funcs(encoder)->mode_set(encoder, mode, adjusted_mode);
 167}
 168EXPORT_SYMBOL(drm_i2c_encoder_mode_set);
 169
 170enum drm_connector_status drm_i2c_encoder_detect(struct drm_encoder *encoder,
 171            struct drm_connector *connector)
 172{
 173        return get_slave_funcs(encoder)->detect(encoder, connector);
 174}
 175EXPORT_SYMBOL(drm_i2c_encoder_detect);
 176
 177void drm_i2c_encoder_save(struct drm_encoder *encoder)
 178{
 179        get_slave_funcs(encoder)->save(encoder);
 180}
 181EXPORT_SYMBOL(drm_i2c_encoder_save);
 182
 183void drm_i2c_encoder_restore(struct drm_encoder *encoder)
 184{
 185        get_slave_funcs(encoder)->restore(encoder);
 186}
 187EXPORT_SYMBOL(drm_i2c_encoder_restore);
 188