drivers/gpu/drm/bridge/ti-tfp410.c

   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         .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_mode_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", &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");