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_crtc_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_mode_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 .dpms = drm_atomic_helper_connector_dpms, 106 .detect = tfp410_connector_detect, 107 .fill_modes = drm_helper_probe_single_connector_modes, 108 .destroy = drm_connector_cleanup, 109 .reset = drm_atomic_helper_connector_reset, 110 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, 111 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, 112 }; 113 114 static int tfp410_attach(struct drm_bridge *bridge) 115 { 116 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 117 int ret; 118 119 if (!bridge->encoder) { 120 dev_err(dvi->dev, "Missing encoder\n"); 121 return -ENODEV; 122 } 123 124 if (dvi->hpd) 125 dvi->connector.polled = DRM_CONNECTOR_POLL_HPD; 126 127 drm_connector_helper_add(&dvi->connector, 128 &tfp410_con_helper_funcs); 129 ret = drm_connector_init(bridge->dev, &dvi->connector, 130 &tfp410_con_funcs, DRM_MODE_CONNECTOR_HDMIA); 131 if (ret) { 132 dev_err(dvi->dev, "drm_connector_init() failed: %d\n", ret); 133 return ret; 134 } 135 136 drm_mode_connector_attach_encoder(&dvi->connector, 137 bridge->encoder); 138 139 return 0; 140 } 141 142 static const struct drm_bridge_funcs tfp410_bridge_funcs = { 143 .attach = tfp410_attach, 144 }; 145 146 static void tfp410_hpd_work_func(struct work_struct *work) 147 { 148 struct tfp410 *dvi; 149 150 dvi = container_of(work, struct tfp410, hpd_work.work); 151 152 if (dvi->bridge.dev) 153 drm_helper_hpd_irq_event(dvi->bridge.dev); 154 } 155 156 static irqreturn_t tfp410_hpd_irq_thread(int irq, void *arg) 157 { 158 struct tfp410 *dvi = arg; 159 160 mod_delayed_work(system_wq, &dvi->hpd_work, 161 msecs_to_jiffies(HOTPLUG_DEBOUNCE_MS)); 162 163 return IRQ_HANDLED; 164 } 165 166 static int tfp410_get_connector_properties(struct tfp410 *dvi) 167 { 168 struct device_node *ep = NULL, *connector_node = NULL; 169 struct device_node *ddc_phandle = NULL; 170 int ret = 0; 171 172 /* port@1 is the connector node */ 173 ep = of_graph_get_endpoint_by_regs(dvi->dev->of_node, 1, -1); 174 if (!ep) 175 goto fail; 176 177 connector_node = of_graph_get_remote_port_parent(ep); 178 if (!connector_node) 179 goto fail; 180 181 dvi->hpd = fwnode_get_named_gpiod(&connector_node->fwnode, 182 "hpd-gpios", 0, GPIOD_IN, "hpd"); 183 if (IS_ERR(dvi->hpd)) { 184 ret = PTR_ERR(dvi->hpd); 185 dvi->hpd = NULL; 186 if (ret == -ENOENT) 187 ret = 0; 188 else 189 goto fail; 190 } 191 192 ddc_phandle = of_parse_phandle(connector_node, "ddc-i2c-bus", 0); 193 if (!ddc_phandle) 194 goto fail; 195 196 dvi->ddc = of_get_i2c_adapter_by_node(ddc_phandle); 197 if (dvi->ddc) 198 dev_info(dvi->dev, "Connector's ddc i2c bus found\n"); 199 else 200 ret = -EPROBE_DEFER; 201 202 fail: 203 of_node_put(ep); 204 of_node_put(connector_node); 205 of_node_put(ddc_phandle); 206 return ret; 207 } 208 209 static int tfp410_init(struct device *dev) 210 { 211 struct tfp410 *dvi; 212 int ret; 213 214 if (!dev->of_node) { 215 dev_err(dev, "device-tree data is missing\n"); 216 return -ENXIO; 217 } 218 219 dvi = devm_kzalloc(dev, sizeof(*dvi), GFP_KERNEL); 220 if (!dvi) 221 return -ENOMEM; 222 dev_set_drvdata(dev, dvi); 223 224 dvi->bridge.funcs = &tfp410_bridge_funcs; 225 dvi->bridge.of_node = dev->of_node; 226 dvi->dev = dev; 227 228 ret = tfp410_get_connector_properties(dvi); 229 if (ret) 230 goto fail; 231 232 if (dvi->hpd) { 233 INIT_DELAYED_WORK(&dvi->hpd_work, tfp410_hpd_work_func); 234 235 ret = devm_request_threaded_irq(dev, gpiod_to_irq(dvi->hpd), 236 NULL, tfp410_hpd_irq_thread, IRQF_TRIGGER_RISING | 237 IRQF_TRIGGER_FALLING | IRQF_ONESHOT, 238 "hdmi-hpd", dvi); 239 if (ret) { 240 DRM_ERROR("failed to register hpd interrupt\n"); 241 goto fail; 242 } 243 } 244 245 ret = drm_bridge_add(&dvi->bridge); 246 if (ret) { 247 dev_err(dev, "drm_bridge_add() failed: %d\n", ret); 248 goto fail; 249 } 250 251 return 0; 252 fail: 253 i2c_put_adapter(dvi->ddc); 254 if (dvi->hpd) 255 gpiod_put(dvi->hpd); 256 return ret; 257 } 258 259 static int tfp410_fini(struct device *dev) 260 { 261 struct tfp410 *dvi = dev_get_drvdata(dev); 262 263 cancel_delayed_work_sync(&dvi->hpd_work); 264 265 drm_bridge_remove(&dvi->bridge); 266 267 if (dvi->ddc) 268 i2c_put_adapter(dvi->ddc); 269 if (dvi->hpd) 270 gpiod_put(dvi->hpd); 271 272 return 0; 273 } 274 275 static int tfp410_probe(struct platform_device *pdev) 276 { 277 return tfp410_init(&pdev->dev); 278 } 279 280 static int tfp410_remove(struct platform_device *pdev) 281 { 282 return tfp410_fini(&pdev->dev); 283 } 284 285 static const struct of_device_id tfp410_match[] = { 286 { .compatible = "ti,tfp410" }, 287 {}, 288 }; 289 MODULE_DEVICE_TABLE(of, tfp410_match); 290 291 static struct platform_driver tfp410_platform_driver = { 292 .probe = tfp410_probe, 293 .remove = tfp410_remove, 294 .driver = { 295 .name = "tfp410-bridge", 296 .of_match_table = tfp410_match, 297 }, 298 }; 299 300 #if IS_ENABLED(CONFIG_I2C) 301 /* There is currently no i2c functionality. */ 302 static int tfp410_i2c_probe(struct i2c_client *client, 303 const struct i2c_device_id *id) 304 { 305 int reg; 306 307 if (!client->dev.of_node || 308 of_property_read_u32(client->dev.of_node, "reg", ®)) { 309 dev_err(&client->dev, 310 "Can't get i2c reg property from device-tree\n"); 311 return -ENXIO; 312 } 313 314 return tfp410_init(&client->dev); 315 } 316 317 static int tfp410_i2c_remove(struct i2c_client *client) 318 { 319 return tfp410_fini(&client->dev); 320 } 321 322 static const struct i2c_device_id tfp410_i2c_ids[] = { 323 { "tfp410", 0 }, 324 { } 325 }; 326 MODULE_DEVICE_TABLE(i2c, tfp410_i2c_ids); 327 328 static struct i2c_driver tfp410_i2c_driver = { 329 .driver = { 330 .name = "tfp410", 331 .of_match_table = of_match_ptr(tfp410_match), 332 }, 333 .id_table = tfp410_i2c_ids, 334 .probe = tfp410_i2c_probe, 335 .remove = tfp410_i2c_remove, 336 }; 337 #endif /* IS_ENABLED(CONFIG_I2C) */ 338 339 static struct { 340 uint i2c:1; 341 uint platform:1; 342 } tfp410_registered_driver; 343 344 static int __init tfp410_module_init(void) 345 { 346 int ret; 347 348 #if IS_ENABLED(CONFIG_I2C) 349 ret = i2c_add_driver(&tfp410_i2c_driver); 350 if (ret) 351 pr_err("%s: registering i2c driver failed: %d", 352 __func__, ret); 353 else 354 tfp410_registered_driver.i2c = 1; 355 #endif 356 357 ret = platform_driver_register(&tfp410_platform_driver); 358 if (ret) 359 pr_err("%s: registering platform driver failed: %d", 360 __func__, ret); 361 else 362 tfp410_registered_driver.platform = 1; 363 364 if (tfp410_registered_driver.i2c || 365 tfp410_registered_driver.platform) 366 return 0; 367 368 return ret; 369 } 370 module_init(tfp410_module_init); 371 372 static void __exit tfp410_module_exit(void) 373 { 374 #if IS_ENABLED(CONFIG_I2C) 375 if (tfp410_registered_driver.i2c) 376 i2c_del_driver(&tfp410_i2c_driver); 377 #endif 378 if (tfp410_registered_driver.platform) 379 platform_driver_unregister(&tfp410_platform_driver); 380 } 381 module_exit(tfp410_module_exit); 382 383 MODULE_AUTHOR("Jyri Sarha <jsarha@ti.com>"); 384 MODULE_DESCRIPTION("TI TFP410 DVI bridge driver"); 385 MODULE_LICENSE("GPL"); 386