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_client_device(adap, info); 65 if (!i2c_client_has_driver(client)) { 66 err = -ENODEV; 67 goto fail_unregister; 68 } 69 70 module = client->dev.driver->owner; 71 if (!try_module_get(module)) { 72 err = -ENODEV; 73 goto fail_unregister; 74 } 75 76 encoder->bus_priv = client; 77 78 encoder_drv = to_drm_i2c_encoder_driver(to_i2c_driver(client->dev.driver)); 79 80 err = encoder_drv->encoder_init(client, dev, encoder); 81 if (err) 82 goto fail_module_put; 83 84 if (info->platform_data) 85 encoder->slave_funcs->set_config(&encoder->base, 86 info->platform_data); 87 88 return 0; 89 90 fail_module_put: 91 module_put(module); 92 fail_unregister: 93 i2c_unregister_device(client); 94 return err; 95 } 96 EXPORT_SYMBOL(drm_i2c_encoder_init); 97 98 /** 99 * drm_i2c_encoder_destroy - Unregister the I2C device backing an encoder 100 * @drm_encoder: Encoder to be unregistered. 101 * 102 * This should be called from the @destroy method of an I2C slave 103 * encoder driver once I2C access is no longer needed. 104 */ 105 void drm_i2c_encoder_destroy(struct drm_encoder *drm_encoder) 106 { 107 struct drm_encoder_slave *encoder = to_encoder_slave(drm_encoder); 108 struct i2c_client *client = drm_i2c_encoder_get_client(drm_encoder); 109 struct module *module = client->dev.driver->owner; 110 111 i2c_unregister_device(client); 112 encoder->bus_priv = NULL; 113 114 module_put(module); 115 } 116 EXPORT_SYMBOL(drm_i2c_encoder_destroy); 117 118 /* 119 * Wrapper fxns which can be plugged in to drm_encoder_helper_funcs: 120 */ 121 122 static inline const struct drm_encoder_slave_funcs * 123 get_slave_funcs(struct drm_encoder *enc) 124 { 125 return to_encoder_slave(enc)->slave_funcs; 126 } 127 128 void drm_i2c_encoder_dpms(struct drm_encoder *encoder, int mode) 129 { 130 get_slave_funcs(encoder)->dpms(encoder, mode); 131 } 132 EXPORT_SYMBOL(drm_i2c_encoder_dpms); 133 134 bool drm_i2c_encoder_mode_fixup(struct drm_encoder *encoder, 135 const struct drm_display_mode *mode, 136 struct drm_display_mode *adjusted_mode) 137 { 138 if (!get_slave_funcs(encoder)->mode_fixup) 139 return true; 140 141 return get_slave_funcs(encoder)->mode_fixup(encoder, mode, adjusted_mode); 142 } 143 EXPORT_SYMBOL(drm_i2c_encoder_mode_fixup); 144 145 void drm_i2c_encoder_prepare(struct drm_encoder *encoder) 146 { 147 drm_i2c_encoder_dpms(encoder, DRM_MODE_DPMS_OFF); 148 } 149 EXPORT_SYMBOL(drm_i2c_encoder_prepare); 150 151 void drm_i2c_encoder_commit(struct drm_encoder *encoder) 152 { 153 drm_i2c_encoder_dpms(encoder, DRM_MODE_DPMS_ON); 154 } 155 EXPORT_SYMBOL(drm_i2c_encoder_commit); 156 157 void drm_i2c_encoder_mode_set(struct drm_encoder *encoder, 158 struct drm_display_mode *mode, 159 struct drm_display_mode *adjusted_mode) 160 { 161 get_slave_funcs(encoder)->mode_set(encoder, mode, adjusted_mode); 162 } 163 EXPORT_SYMBOL(drm_i2c_encoder_mode_set); 164 165 enum drm_connector_status drm_i2c_encoder_detect(struct drm_encoder *encoder, 166 struct drm_connector *connector) 167 { 168 return get_slave_funcs(encoder)->detect(encoder, connector); 169 } 170 EXPORT_SYMBOL(drm_i2c_encoder_detect); 171 172 void drm_i2c_encoder_save(struct drm_encoder *encoder) 173 { 174 get_slave_funcs(encoder)->save(encoder); 175 } 176 EXPORT_SYMBOL(drm_i2c_encoder_save); 177 178 void drm_i2c_encoder_restore(struct drm_encoder *encoder) 179 { 180 get_slave_funcs(encoder)->restore(encoder); 181 } 182 EXPORT_SYMBOL(drm_i2c_encoder_restore); 183