1 /* 2 * Copyright (C) 2016 Texas Instruments 3 * Author: Jyri Sarha <jsarha@ti.com> 4 * 5 * This program is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 as published by 7 * the Free Software Foundation. 8 * 9 */ 10 11 #include <linux/delay.h> 12 #include <linux/fwnode.h> 13 #include <linux/gpio/consumer.h> 14 #include <linux/irq.h> 15 #include <linux/module.h> 16 #include <linux/of_graph.h> 17 #include <linux/platform_device.h> 18 #include <linux/i2c.h> 19 20 #include <drm/drmP.h> 21 #include <drm/drm_atomic_helper.h> 22 #include <drm/drm_crtc.h> 23 #include <drm/drm_probe_helper.h> 24 25 #define HOTPLUG_DEBOUNCE_MS 1100 26 27 struct tfp410 { 28 struct drm_bridge bridge; 29 struct drm_connector connector; 30 31 struct i2c_adapter *ddc; 32 struct gpio_desc *hpd; 33 struct delayed_work hpd_work; 34 35 struct device *dev; 36 }; 37 38 static inline struct tfp410 * 39 drm_bridge_to_tfp410(struct drm_bridge *bridge) 40 { 41 return container_of(bridge, struct tfp410, bridge); 42 } 43 44 static inline struct tfp410 * 45 drm_connector_to_tfp410(struct drm_connector *connector) 46 { 47 return container_of(connector, struct tfp410, connector); 48 } 49 50 static int tfp410_get_modes(struct drm_connector *connector) 51 { 52 struct tfp410 *dvi = drm_connector_to_tfp410(connector); 53 struct edid *edid; 54 int ret; 55 56 if (!dvi->ddc) 57 goto fallback; 58 59 edid = drm_get_edid(connector, dvi->ddc); 60 if (!edid) { 61 DRM_INFO("EDID read failed. Fallback to standard modes\n"); 62 goto fallback; 63 } 64 65 drm_connector_update_edid_property(connector, edid); 66 67 return drm_add_edid_modes(connector, edid); 68 fallback: 69 /* No EDID, fallback on the XGA standard modes */ 70 ret = drm_add_modes_noedid(connector, 1920, 1200); 71 72 /* And prefer a mode pretty much anything can handle */ 73 drm_set_preferred_mode(connector, 1024, 768); 74 75 return ret; 76 } 77 78 static const struct drm_connector_helper_funcs tfp410_con_helper_funcs = { 79 .get_modes = tfp410_get_modes, 80 }; 81 82 static enum drm_connector_status 83 tfp410_connector_detect(struct drm_connector *connector, bool force) 84 { 85 struct tfp410 *dvi = drm_connector_to_tfp410(connector); 86 87 if (dvi->hpd) { 88 if (gpiod_get_value_cansleep(dvi->hpd)) 89 return connector_status_connected; 90 else 91 return connector_status_disconnected; 92 } 93 94 if (dvi->ddc) { 95 if (drm_probe_ddc(dvi->ddc)) 96 return connector_status_connected; 97 else 98 return connector_status_disconnected; 99 } 100 101 return connector_status_unknown; 102 } 103 104 static const struct drm_connector_funcs tfp410_con_funcs = { 105 .detect = tfp410_connector_detect, 106 .fill_modes = drm_helper_probe_single_connector_modes, 107 .destroy = drm_connector_cleanup, 108 .reset = drm_atomic_helper_connector_reset, 109 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, 110 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, 111 }; 112 113 static int tfp410_attach(struct drm_bridge *bridge) 114 { 115 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 116 int ret; 117 118 if (!bridge->encoder) { 119 dev_err(dvi->dev, "Missing encoder\n"); 120 return -ENODEV; 121 } 122 123 if (dvi->hpd) 124 dvi->connector.polled = DRM_CONNECTOR_POLL_HPD; 125 126 drm_connector_helper_add(&dvi->connector, 127 &tfp410_con_helper_funcs); 128 ret = drm_connector_init(bridge->dev, &dvi->connector, 129 &tfp410_con_funcs, DRM_MODE_CONNECTOR_HDMIA); 130 if (ret) { 131 dev_err(dvi->dev, "drm_connector_init() failed: %d\n", ret); 132 return ret; 133 } 134 135 drm_connector_attach_encoder(&dvi->connector, 136 bridge->encoder); 137 138 return 0; 139 } 140 141 static const struct drm_bridge_funcs tfp410_bridge_funcs = { 142 .attach = tfp410_attach, 143 }; 144 145 static void tfp410_hpd_work_func(struct work_struct *work) 146 { 147 struct tfp410 *dvi; 148 149 dvi = container_of(work, struct tfp410, hpd_work.work); 150 151 if (dvi->bridge.dev) 152 drm_helper_hpd_irq_event(dvi->bridge.dev); 153 } 154 155 static irqreturn_t tfp410_hpd_irq_thread(int irq, void *arg) 156 { 157 struct tfp410 *dvi = arg; 158 159 mod_delayed_work(system_wq, &dvi->hpd_work, 160 msecs_to_jiffies(HOTPLUG_DEBOUNCE_MS)); 161 162 return IRQ_HANDLED; 163 } 164 165 static int tfp410_get_connector_properties(struct tfp410 *dvi) 166 { 167 struct device_node *connector_node, *ddc_phandle; 168 int ret = 0; 169 170 /* port@1 is the connector node */ 171 connector_node = of_graph_get_remote_node(dvi->dev->of_node, 1, -1); 172 if (!connector_node) 173 return -ENODEV; 174 175 dvi->hpd = fwnode_get_named_gpiod(&connector_node->fwnode, 176 "hpd-gpios", 0, GPIOD_IN, "hpd"); 177 if (IS_ERR(dvi->hpd)) { 178 ret = PTR_ERR(dvi->hpd); 179 dvi->hpd = NULL; 180 if (ret == -ENOENT) 181 ret = 0; 182 else 183 goto fail; 184 } 185 186 ddc_phandle = of_parse_phandle(connector_node, "ddc-i2c-bus", 0); 187 if (!ddc_phandle) 188 goto fail; 189 190 dvi->ddc = of_get_i2c_adapter_by_node(ddc_phandle); 191 if (dvi->ddc) 192 dev_info(dvi->dev, "Connector's ddc i2c bus found\n"); 193 else 194 ret = -EPROBE_DEFER; 195 196 of_node_put(ddc_phandle); 197 198 fail: 199 of_node_put(connector_node); 200 return ret; 201 } 202 203 static int tfp410_init(struct device *dev) 204 { 205 struct tfp410 *dvi; 206 int ret; 207 208 if (!dev->of_node) { 209 dev_err(dev, "device-tree data is missing\n"); 210 return -ENXIO; 211 } 212 213 dvi = devm_kzalloc(dev, sizeof(*dvi), GFP_KERNEL); 214 if (!dvi) 215 return -ENOMEM; 216 dev_set_drvdata(dev, dvi); 217 218 dvi->bridge.funcs = &tfp410_bridge_funcs; 219 dvi->bridge.of_node = dev->of_node; 220 dvi->dev = dev; 221 222 ret = tfp410_get_connector_properties(dvi); 223 if (ret) 224 goto fail; 225 226 if (dvi->hpd) { 227 INIT_DELAYED_WORK(&dvi->hpd_work, tfp410_hpd_work_func); 228 229 ret = devm_request_threaded_irq(dev, gpiod_to_irq(dvi->hpd), 230 NULL, tfp410_hpd_irq_thread, IRQF_TRIGGER_RISING | 231 IRQF_TRIGGER_FALLING | IRQF_ONESHOT, 232 "hdmi-hpd", dvi); 233 if (ret) { 234 DRM_ERROR("failed to register hpd interrupt\n"); 235 goto fail; 236 } 237 } 238 239 drm_bridge_add(&dvi->bridge); 240 241 return 0; 242 fail: 243 i2c_put_adapter(dvi->ddc); 244 if (dvi->hpd) 245 gpiod_put(dvi->hpd); 246 return ret; 247 } 248 249 static int tfp410_fini(struct device *dev) 250 { 251 struct tfp410 *dvi = dev_get_drvdata(dev); 252 253 cancel_delayed_work_sync(&dvi->hpd_work); 254 255 drm_bridge_remove(&dvi->bridge); 256 257 if (dvi->ddc) 258 i2c_put_adapter(dvi->ddc); 259 if (dvi->hpd) 260 gpiod_put(dvi->hpd); 261 262 return 0; 263 } 264 265 static int tfp410_probe(struct platform_device *pdev) 266 { 267 return tfp410_init(&pdev->dev); 268 } 269 270 static int tfp410_remove(struct platform_device *pdev) 271 { 272 return tfp410_fini(&pdev->dev); 273 } 274 275 static const struct of_device_id tfp410_match[] = { 276 { .compatible = "ti,tfp410" }, 277 {}, 278 }; 279 MODULE_DEVICE_TABLE(of, tfp410_match); 280 281 static struct platform_driver tfp410_platform_driver = { 282 .probe = tfp410_probe, 283 .remove = tfp410_remove, 284 .driver = { 285 .name = "tfp410-bridge", 286 .of_match_table = tfp410_match, 287 }, 288 }; 289 290 #if IS_ENABLED(CONFIG_I2C) 291 /* There is currently no i2c functionality. */ 292 static int tfp410_i2c_probe(struct i2c_client *client, 293 const struct i2c_device_id *id) 294 { 295 int reg; 296 297 if (!client->dev.of_node || 298 of_property_read_u32(client->dev.of_node, "reg", ®)) { 299 dev_err(&client->dev, 300 "Can't get i2c reg property from device-tree\n"); 301 return -ENXIO; 302 } 303 304 return tfp410_init(&client->dev); 305 } 306 307 static int tfp410_i2c_remove(struct i2c_client *client) 308 { 309 return tfp410_fini(&client->dev); 310 } 311 312 static const struct i2c_device_id tfp410_i2c_ids[] = { 313 { "tfp410", 0 }, 314 { } 315 }; 316 MODULE_DEVICE_TABLE(i2c, tfp410_i2c_ids); 317 318 static struct i2c_driver tfp410_i2c_driver = { 319 .driver = { 320 .name = "tfp410", 321 .of_match_table = of_match_ptr(tfp410_match), 322 }, 323 .id_table = tfp410_i2c_ids, 324 .probe = tfp410_i2c_probe, 325 .remove = tfp410_i2c_remove, 326 }; 327 #endif /* IS_ENABLED(CONFIG_I2C) */ 328 329 static struct { 330 uint i2c:1; 331 uint platform:1; 332 } tfp410_registered_driver; 333 334 static int __init tfp410_module_init(void) 335 { 336 int ret; 337 338 #if IS_ENABLED(CONFIG_I2C) 339 ret = i2c_add_driver(&tfp410_i2c_driver); 340 if (ret) 341 pr_err("%s: registering i2c driver failed: %d", 342 __func__, ret); 343 else 344 tfp410_registered_driver.i2c = 1; 345 #endif 346 347 ret = platform_driver_register(&tfp410_platform_driver); 348 if (ret) 349 pr_err("%s: registering platform driver failed: %d", 350 __func__, ret); 351 else 352 tfp410_registered_driver.platform = 1; 353 354 if (tfp410_registered_driver.i2c || 355 tfp410_registered_driver.platform) 356 return 0; 357 358 return ret; 359 } 360 module_init(tfp410_module_init); 361 362 static void __exit tfp410_module_exit(void) 363 { 364 #if IS_ENABLED(CONFIG_I2C) 365 if (tfp410_registered_driver.i2c) 366 i2c_del_driver(&tfp410_i2c_driver); 367 #endif 368 if (tfp410_registered_driver.platform) 369 platform_driver_unregister(&tfp410_platform_driver); 370 } 371 module_exit(tfp410_module_exit); 372 373 MODULE_AUTHOR("Jyri Sarha <jsarha@ti.com>"); 374 MODULE_DESCRIPTION("TI TFP410 DVI bridge driver"); 375 MODULE_LICENSE("GPL"); 376