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 */ 52 int 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 95 fail_unregister: 96 i2c_unregister_device(client); 97 module_put(module); 98 fail: 99 return err; 100 } 101 EXPORT_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 */ 110 void 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 } 121 EXPORT_SYMBOL(drm_i2c_encoder_destroy); 122 123 /* 124 * Wrapper fxns which can be plugged in to drm_encoder_helper_funcs: 125 */ 126 127 static inline struct drm_encoder_slave_funcs * 128 get_slave_funcs(struct drm_encoder *enc) 129 { 130 return to_encoder_slave(enc)->slave_funcs; 131 } 132 133 void drm_i2c_encoder_dpms(struct drm_encoder *encoder, int mode) 134 { 135 get_slave_funcs(encoder)->dpms(encoder, mode); 136 } 137 EXPORT_SYMBOL(drm_i2c_encoder_dpms); 138 139 bool 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 return get_slave_funcs(encoder)->mode_fixup(encoder, mode, adjusted_mode); 144 } 145 EXPORT_SYMBOL(drm_i2c_encoder_mode_fixup); 146 147 void drm_i2c_encoder_prepare(struct drm_encoder *encoder) 148 { 149 drm_i2c_encoder_dpms(encoder, DRM_MODE_DPMS_OFF); 150 } 151 EXPORT_SYMBOL(drm_i2c_encoder_prepare); 152 153 void drm_i2c_encoder_commit(struct drm_encoder *encoder) 154 { 155 drm_i2c_encoder_dpms(encoder, DRM_MODE_DPMS_ON); 156 } 157 EXPORT_SYMBOL(drm_i2c_encoder_commit); 158 159 void drm_i2c_encoder_mode_set(struct drm_encoder *encoder, 160 struct drm_display_mode *mode, 161 struct drm_display_mode *adjusted_mode) 162 { 163 get_slave_funcs(encoder)->mode_set(encoder, mode, adjusted_mode); 164 } 165 EXPORT_SYMBOL(drm_i2c_encoder_mode_set); 166 167 enum drm_connector_status drm_i2c_encoder_detect(struct drm_encoder *encoder, 168 struct drm_connector *connector) 169 { 170 return get_slave_funcs(encoder)->detect(encoder, connector); 171 } 172 EXPORT_SYMBOL(drm_i2c_encoder_detect); 173 174 void drm_i2c_encoder_save(struct drm_encoder *encoder) 175 { 176 get_slave_funcs(encoder)->save(encoder); 177 } 178 EXPORT_SYMBOL(drm_i2c_encoder_save); 179 180 void drm_i2c_encoder_restore(struct drm_encoder *encoder) 181 { 182 get_slave_funcs(encoder)->restore(encoder); 183 } 184 EXPORT_SYMBOL(drm_i2c_encoder_restore); 185