sys/dev/drm/drm_encoder_slave.c

   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 #if 0
  32 /**
  33  * drm_i2c_encoder_init - Initialize an I2C slave encoder
  34  * @dev:        DRM device.
  35  * @encoder:    Encoder to be attached to the I2C device. You aren't
  36  *              required to have called drm_encoder_init() before.
  37  * @adap:       I2C adapter that will be used to communicate with
  38  *              the device.
  39  * @info:       Information that will be used to create the I2C device.
  40  *              Required fields are @addr and @type.
  41  *
  42  * Create an I2C device on the specified bus (the module containing its
  43  * driver is transparently loaded) and attach it to the specified
  44  * &drm_encoder_slave. The @slave_funcs field will be initialized with
  45  * the hooks provided by the slave driver.
  46  *
  47  * If @info.platform_data is non-NULL it will be used as the initial
  48  * slave config.
  49  *
  50  * Returns 0 on success or a negative errno on failure, in particular,
  51  * -ENODEV is returned when no matching driver is found.
  52  */
  53 int drm_i2c_encoder_init(struct drm_device *dev,
  54                          struct drm_encoder_slave *encoder,
  55                          struct i2c_adapter *adap,
  56                          const struct i2c_board_info *info)
  57 {
  58         struct module *module = NULL;
  59         struct i2c_client *client;
  60         struct drm_i2c_encoder_driver *encoder_drv;
  61         int err = 0;
  62
  63         request_module("%s%s", I2C_MODULE_PREFIX, info->type);
  64
  65         client = i2c_new_device(adap, info);
  66         if (!client) {
  67                 err = -ENOMEM;
  68                 goto fail;
  69         }
  70
  71         if (!client->dev.driver) {
  72                 err = -ENODEV;
  73                 goto fail_unregister;
  74         }
  75
  76         module = client->dev.driver->owner;
  77         if (!try_module_get(module)) {
  78                 err = -ENODEV;
  79                 goto fail_unregister;
  80         }
  81
  82         encoder->bus_priv = client;
  83
  84         encoder_drv = to_drm_i2c_encoder_driver(to_i2c_driver(client->dev.driver));
  85
  86         err = encoder_drv->encoder_init(client, dev, encoder);
  87         if (err)
  88                 goto fail_unregister;
  89
  90         if (info->platform_data)
  91                 encoder->slave_funcs->set_config(&encoder->base,
  92                                                  info->platform_data);
  93
  94         return 0;
  95
  96 fail_unregister:
  97         i2c_unregister_device(client);
  98         module_put(module);
  99 fail:
 100         return err;
 101 }
 102 EXPORT_SYMBOL(drm_i2c_encoder_init);
 103
 104 /**
 105  * drm_i2c_encoder_destroy - Unregister the I2C device backing an encoder
 106  * @drm_encoder:        Encoder to be unregistered.
 107  *
 108  * This should be called from the @destroy method of an I2C slave
 109  * encoder driver once I2C access is no longer needed.
 110  */
 111 void drm_i2c_encoder_destroy(struct drm_encoder *drm_encoder)
 112 {
 113         struct drm_encoder_slave *encoder = to_encoder_slave(drm_encoder);
 114         struct i2c_client *client = drm_i2c_encoder_get_client(drm_encoder);
 115         struct module *module = client->dev.driver->owner;
 116
 117         i2c_unregister_device(client);
 118         encoder->bus_priv = NULL;
 119
 120         module_put(module);
 121 }
 122 EXPORT_SYMBOL(drm_i2c_encoder_destroy);
 123 #endif
 124
 125 /*
 126  * Wrapper fxns which can be plugged in to drm_encoder_helper_funcs:
 127  */
 128
 129 static inline const struct drm_encoder_slave_funcs *
 130 get_slave_funcs(struct drm_encoder *enc)
 131 {
 132         return to_encoder_slave(enc)->slave_funcs;
 133 }
 134
 135 void drm_i2c_encoder_dpms(struct drm_encoder *encoder, int mode)
 136 {
 137         get_slave_funcs(encoder)->dpms(encoder, mode);
 138 }
 139 EXPORT_SYMBOL(drm_i2c_encoder_dpms);
 140
 141 bool drm_i2c_encoder_mode_fixup(struct drm_encoder *encoder,
 142                 const struct drm_display_mode *mode,
 143                 struct drm_display_mode *adjusted_mode)
 144 {
 145         if (!get_slave_funcs(encoder)->mode_fixup)
 146                 return true;
 147
 148         return get_slave_funcs(encoder)->mode_fixup(encoder, mode, adjusted_mode);
 149 }
 150 EXPORT_SYMBOL(drm_i2c_encoder_mode_fixup);
 151
 152 void drm_i2c_encoder_prepare(struct drm_encoder *encoder)
 153 {
 154         drm_i2c_encoder_dpms(encoder, DRM_MODE_DPMS_OFF);
 155 }
 156 EXPORT_SYMBOL(drm_i2c_encoder_prepare);
 157
 158 void drm_i2c_encoder_commit(struct drm_encoder *encoder)
 159 {
 160         drm_i2c_encoder_dpms(encoder, DRM_MODE_DPMS_ON);
 161 }
 162 EXPORT_SYMBOL(drm_i2c_encoder_commit);
 163
 164 void drm_i2c_encoder_mode_set(struct drm_encoder *encoder,
 165                 struct drm_display_mode *mode,
 166                 struct drm_display_mode *adjusted_mode)
 167 {
 168         get_slave_funcs(encoder)->mode_set(encoder, mode, adjusted_mode);
 169 }
 170 EXPORT_SYMBOL(drm_i2c_encoder_mode_set);
 171
 172 enum drm_connector_status drm_i2c_encoder_detect(struct drm_encoder *encoder,
 173             struct drm_connector *connector)
 174 {
 175         return get_slave_funcs(encoder)->detect(encoder, connector);
 176 }
 177 EXPORT_SYMBOL(drm_i2c_encoder_detect);
 178
 179 void drm_i2c_encoder_save(struct drm_encoder *encoder)
 180 {
 181         get_slave_funcs(encoder)->save(encoder);
 182 }
 183 EXPORT_SYMBOL(drm_i2c_encoder_save);
 184
 185 void drm_i2c_encoder_restore(struct drm_encoder *encoder)
 186 {
 187         get_slave_funcs(encoder)->restore(encoder);
 188 }
 189 EXPORT_SYMBOL(drm_i2c_encoder_restore);