drivers/gpu/drm/omapdrm/displays/connector-dvi.c

   1 /*
   2  * Generic DVI Connector driver
   3  *
   4  * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com/
   5  * Author: Tomi Valkeinen <tomi.valkeinen@ti.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License version 2 as published by
   9  * the Free Software Foundation.
  10  */
  11
  12 #include <linux/gpio/consumer.h>
  13 #include <linux/i2c.h>
  14 #include <linux/module.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/slab.h>
  17
  18 #include <drm/drm_edid.h>
  19
  20 #include "../dss/omapdss.h"
  21
  22 static const struct videomode dvic_default_vm = {
  23         .hactive        = 640,
  24         .vactive        = 480,
  25
  26         .pixelclock     = 23500000,
  27
  28         .hfront_porch   = 48,
  29         .hsync_len      = 32,
  30         .hback_porch    = 80,
  31
  32         .vfront_porch   = 3,
  33         .vsync_len      = 4,
  34         .vback_porch    = 7,
  35
  36         .flags          = DISPLAY_FLAGS_HSYNC_HIGH | DISPLAY_FLAGS_VSYNC_HIGH |
  37                           DISPLAY_FLAGS_SYNC_NEGEDGE | DISPLAY_FLAGS_DE_HIGH |
  38                           DISPLAY_FLAGS_PIXDATA_POSEDGE,
  39 };
  40
  41 struct panel_drv_data {
  42         struct omap_dss_device dssdev;
  43         struct omap_dss_device *in;
  44
  45         struct videomode vm;
  46
  47         struct i2c_adapter *i2c_adapter;
  48
  49         struct gpio_desc *hpd_gpio;
  50
  51         void (*hpd_cb)(void *cb_data, enum drm_connector_status status);
  52         void *hpd_cb_data;
  53         bool hpd_enabled;
  54         /* mutex for hpd fields above */
  55         struct mutex hpd_lock;
  56 };
  57
  58 #define to_panel_data(x) container_of(x, struct panel_drv_data, dssdev)
  59
  60 static int dvic_connect(struct omap_dss_device *dssdev)
  61 {
  62         struct panel_drv_data *ddata = to_panel_data(dssdev);
  63         struct omap_dss_device *in;
  64         int r;
  65
  66         if (omapdss_device_is_connected(dssdev))
  67                 return 0;
  68
  69         in = omapdss_of_find_source_for_first_ep(dssdev->dev->of_node);
  70         if (IS_ERR(in)) {
  71                 dev_err(dssdev->dev, "failed to find video source\n");
  72                 return PTR_ERR(in);
  73         }
  74
  75         r = in->ops.dvi->connect(in, dssdev);
  76         if (r) {
  77                 omap_dss_put_device(in);
  78                 return r;
  79         }
  80
  81         ddata->in = in;
  82         return 0;
  83 }
  84
  85 static void dvic_disconnect(struct omap_dss_device *dssdev)
  86 {
  87         struct panel_drv_data *ddata = to_panel_data(dssdev);
  88         struct omap_dss_device *in = ddata->in;
  89
  90         if (!omapdss_device_is_connected(dssdev))
  91                 return;
  92
  93         in->ops.dvi->disconnect(in, dssdev);
  94
  95         omap_dss_put_device(in);
  96         ddata->in = NULL;
  97 }
  98
  99 static int dvic_enable(struct omap_dss_device *dssdev)
 100 {
 101         struct panel_drv_data *ddata = to_panel_data(dssdev);
 102         struct omap_dss_device *in = ddata->in;
 103         int r;
 104
 105         if (!omapdss_device_is_connected(dssdev))
 106                 return -ENODEV;
 107
 108         if (omapdss_device_is_enabled(dssdev))
 109                 return 0;
 110
 111         in->ops.dvi->set_timings(in, &ddata->vm);
 112
 113         r = in->ops.dvi->enable(in);
 114         if (r)
 115                 return r;
 116
 117         dssdev->state = OMAP_DSS_DISPLAY_ACTIVE;
 118
 119         return 0;
 120 }
 121
 122 static void dvic_disable(struct omap_dss_device *dssdev)
 123 {
 124         struct panel_drv_data *ddata = to_panel_data(dssdev);
 125         struct omap_dss_device *in = ddata->in;
 126
 127         if (!omapdss_device_is_enabled(dssdev))
 128                 return;
 129
 130         in->ops.dvi->disable(in);
 131
 132         dssdev->state = OMAP_DSS_DISPLAY_DISABLED;
 133 }
 134
 135 static void dvic_set_timings(struct omap_dss_device *dssdev,
 136                              struct videomode *vm)
 137 {
 138         struct panel_drv_data *ddata = to_panel_data(dssdev);
 139         struct omap_dss_device *in = ddata->in;
 140
 141         ddata->vm = *vm;
 142         dssdev->panel.vm = *vm;
 143
 144         in->ops.dvi->set_timings(in, vm);
 145 }
 146
 147 static void dvic_get_timings(struct omap_dss_device *dssdev,
 148                              struct videomode *vm)
 149 {
 150         struct panel_drv_data *ddata = to_panel_data(dssdev);
 151
 152         *vm = ddata->vm;
 153 }
 154
 155 static int dvic_check_timings(struct omap_dss_device *dssdev,
 156                               struct videomode *vm)
 157 {
 158         struct panel_drv_data *ddata = to_panel_data(dssdev);
 159         struct omap_dss_device *in = ddata->in;
 160
 161         return in->ops.dvi->check_timings(in, vm);
 162 }
 163
 164 static int dvic_ddc_read(struct i2c_adapter *adapter,
 165                 unsigned char *buf, u16 count, u8 offset)
 166 {
 167         int r, retries;
 168
 169         for (retries = 3; retries > 0; retries--) {
 170                 struct i2c_msg msgs[] = {
 171                         {
 172                                 .addr   = DDC_ADDR,
 173                                 .flags  = 0,
 174                                 .len    = 1,
 175                                 .buf    = &offset,
 176                         }, {
 177                                 .addr   = DDC_ADDR,
 178                                 .flags  = I2C_M_RD,
 179                                 .len    = count,
 180                                 .buf    = buf,
 181                         }
 182                 };
 183
 184                 r = i2c_transfer(adapter, msgs, 2);
 185                 if (r == 2)
 186                         return 0;
 187
 188                 if (r != -EAGAIN)
 189                         break;
 190         }
 191
 192         return r < 0 ? r : -EIO;
 193 }
 194
 195 static int dvic_read_edid(struct omap_dss_device *dssdev,
 196                 u8 *edid, int len)
 197 {
 198         struct panel_drv_data *ddata = to_panel_data(dssdev);
 199         int r, l, bytes_read;
 200
 201         if (ddata->hpd_gpio && !gpiod_get_value_cansleep(ddata->hpd_gpio))
 202                 return -ENODEV;
 203
 204         if (!ddata->i2c_adapter)
 205                 return -ENODEV;
 206
 207         l = min(EDID_LENGTH, len);
 208         r = dvic_ddc_read(ddata->i2c_adapter, edid, l, 0);
 209         if (r)
 210                 return r;
 211
 212         bytes_read = l;
 213
 214         /* if there are extensions, read second block */
 215         if (len > EDID_LENGTH && edid[0x7e] > 0) {
 216                 l = min(EDID_LENGTH, len - EDID_LENGTH);
 217
 218                 r = dvic_ddc_read(ddata->i2c_adapter, edid + EDID_LENGTH,
 219                                 l, EDID_LENGTH);
 220                 if (r)
 221                         return r;
 222
 223                 bytes_read += l;
 224         }
 225
 226         return bytes_read;
 227 }
 228
 229 static bool dvic_detect(struct omap_dss_device *dssdev)
 230 {
 231         struct panel_drv_data *ddata = to_panel_data(dssdev);
 232         unsigned char out;
 233         int r;
 234
 235         if (ddata->hpd_gpio)
 236                 return gpiod_get_value_cansleep(ddata->hpd_gpio);
 237
 238         if (!ddata->i2c_adapter)
 239                 return true;
 240
 241         r = dvic_ddc_read(ddata->i2c_adapter, &out, 1, 0);
 242
 243         return r == 0;
 244 }
 245
 246 static int dvic_register_hpd_cb(struct omap_dss_device *dssdev,
 247                                  void (*cb)(void *cb_data,
 248                                             enum drm_connector_status status),
 249                                  void *cb_data)
 250 {
 251         struct panel_drv_data *ddata = to_panel_data(dssdev);
 252
 253         if (!ddata->hpd_gpio)
 254                 return -ENOTSUPP;
 255
 256         mutex_lock(&ddata->hpd_lock);
 257         ddata->hpd_cb = cb;
 258         ddata->hpd_cb_data = cb_data;
 259         mutex_unlock(&ddata->hpd_lock);
 260         return 0;
 261 }
 262
 263 static void dvic_unregister_hpd_cb(struct omap_dss_device *dssdev)
 264 {
 265         struct panel_drv_data *ddata = to_panel_data(dssdev);
 266
 267         if (!ddata->hpd_gpio)
 268                 return;
 269
 270         mutex_lock(&ddata->hpd_lock);
 271         ddata->hpd_cb = NULL;
 272         ddata->hpd_cb_data = NULL;
 273         mutex_unlock(&ddata->hpd_lock);
 274 }
 275
 276 static void dvic_enable_hpd(struct omap_dss_device *dssdev)
 277 {
 278         struct panel_drv_data *ddata = to_panel_data(dssdev);
 279
 280         if (!ddata->hpd_gpio)
 281                 return;
 282
 283         mutex_lock(&ddata->hpd_lock);
 284         ddata->hpd_enabled = true;
 285         mutex_unlock(&ddata->hpd_lock);
 286 }
 287
 288 static void dvic_disable_hpd(struct omap_dss_device *dssdev)
 289 {
 290         struct panel_drv_data *ddata = to_panel_data(dssdev);
 291
 292         if (!ddata->hpd_gpio)
 293                 return;
 294
 295         mutex_lock(&ddata->hpd_lock);
 296         ddata->hpd_enabled = false;
 297         mutex_unlock(&ddata->hpd_lock);
 298 }
 299
 300 static struct omap_dss_driver dvic_driver = {
 301         .connect        = dvic_connect,
 302         .disconnect     = dvic_disconnect,
 303
 304         .enable         = dvic_enable,
 305         .disable        = dvic_disable,
 306
 307         .set_timings    = dvic_set_timings,
 308         .get_timings    = dvic_get_timings,
 309         .check_timings  = dvic_check_timings,
 310
 311         .read_edid      = dvic_read_edid,
 312         .detect         = dvic_detect,
 313
 314         .register_hpd_cb        = dvic_register_hpd_cb,
 315         .unregister_hpd_cb      = dvic_unregister_hpd_cb,
 316         .enable_hpd             = dvic_enable_hpd,
 317         .disable_hpd            = dvic_disable_hpd,
 318 };
 319
 320 static irqreturn_t dvic_hpd_isr(int irq, void *data)
 321 {
 322         struct panel_drv_data *ddata = data;
 323
 324         mutex_lock(&ddata->hpd_lock);
 325         if (ddata->hpd_enabled && ddata->hpd_cb) {
 326                 enum drm_connector_status status;
 327
 328                 if (dvic_detect(&ddata->dssdev))
 329                         status = connector_status_connected;
 330                 else
 331                         status = connector_status_disconnected;
 332
 333                 ddata->hpd_cb(ddata->hpd_cb_data, status);
 334         }
 335         mutex_unlock(&ddata->hpd_lock);
 336
 337         return IRQ_HANDLED;
 338 }
 339
 340 static int dvic_probe_of(struct platform_device *pdev)
 341 {
 342         struct panel_drv_data *ddata = platform_get_drvdata(pdev);
 343         struct device_node *node = pdev->dev.of_node;
 344         struct device_node *adapter_node;
 345         struct i2c_adapter *adapter;
 346         struct gpio_desc *gpio;
 347         int r;
 348
 349         gpio = devm_gpiod_get_optional(&pdev->dev, "hpd", GPIOD_IN);
 350         if (IS_ERR(gpio)) {
 351                 dev_err(&pdev->dev, "failed to parse HPD gpio\n");
 352                 return PTR_ERR(gpio);
 353         }
 354
 355         ddata->hpd_gpio = gpio;
 356
 357         mutex_init(&ddata->hpd_lock);
 358
 359         if (ddata->hpd_gpio) {
 360                 r = devm_request_threaded_irq(&pdev->dev,
 361                         gpiod_to_irq(ddata->hpd_gpio), NULL, dvic_hpd_isr,
 362                         IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
 363                         "DVI HPD", ddata);
 364                 if (r)
 365                         return r;
 366         }
 367
 368         adapter_node = of_parse_phandle(node, "ddc-i2c-bus", 0);
 369         if (adapter_node) {
 370                 adapter = of_get_i2c_adapter_by_node(adapter_node);
 371                 of_node_put(adapter_node);
 372                 if (adapter == NULL) {
 373                         dev_err(&pdev->dev, "failed to parse ddc-i2c-bus\n");
 374                         return -EPROBE_DEFER;
 375                 }
 376
 377                 ddata->i2c_adapter = adapter;
 378         }
 379
 380         return 0;
 381 }
 382
 383 static int dvic_probe(struct platform_device *pdev)
 384 {
 385         struct panel_drv_data *ddata;
 386         struct omap_dss_device *dssdev;
 387         int r;
 388
 389         ddata = devm_kzalloc(&pdev->dev, sizeof(*ddata), GFP_KERNEL);
 390         if (!ddata)
 391                 return -ENOMEM;
 392
 393         platform_set_drvdata(pdev, ddata);
 394
 395         r = dvic_probe_of(pdev);
 396         if (r)
 397                 return r;
 398
 399         ddata->vm = dvic_default_vm;
 400
 401         dssdev = &ddata->dssdev;
 402         dssdev->driver = &dvic_driver;
 403         dssdev->dev = &pdev->dev;
 404         dssdev->type = OMAP_DISPLAY_TYPE_DVI;
 405         dssdev->owner = THIS_MODULE;
 406         dssdev->panel.vm = dvic_default_vm;
 407
 408         r = omapdss_register_display(dssdev);
 409         if (r) {
 410                 dev_err(&pdev->dev, "Failed to register panel\n");
 411                 goto err_reg;
 412         }
 413
 414         return 0;
 415
 416 err_reg:
 417         i2c_put_adapter(ddata->i2c_adapter);
 418         mutex_destroy(&ddata->hpd_lock);
 419
 420         return r;
 421 }
 422
 423 static int __exit dvic_remove(struct platform_device *pdev)
 424 {
 425         struct panel_drv_data *ddata = platform_get_drvdata(pdev);
 426         struct omap_dss_device *dssdev = &ddata->dssdev;
 427
 428         omapdss_unregister_display(&ddata->dssdev);
 429
 430         dvic_disable(dssdev);
 431         dvic_disconnect(dssdev);
 432
 433         i2c_put_adapter(ddata->i2c_adapter);
 434
 435         mutex_destroy(&ddata->hpd_lock);
 436
 437         return 0;
 438 }
 439
 440 static const struct of_device_id dvic_of_match[] = {
 441         { .compatible = "omapdss,dvi-connector", },
 442         {},
 443 };
 444
 445 MODULE_DEVICE_TABLE(of, dvic_of_match);
 446
 447 static struct platform_driver dvi_connector_driver = {
 448         .probe  = dvic_probe,
 449         .remove = __exit_p(dvic_remove),
 450         .driver = {
 451                 .name   = "connector-dvi",
 452                 .of_match_table = dvic_of_match,
 453                 .suppress_bind_attrs = true,
 454         },
 455 };
 456
 457 module_platform_driver(dvi_connector_driver);
 458
 459 MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
 460 MODULE_DESCRIPTION("Generic DVI Connector driver");
 461 MODULE_LICENSE("GPL");