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

   1 /*
   2  * Generic DVI Connector driver
   3  *
   4  * Copyright (C) 2013 Texas Instruments
   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/i2c.h>
  13 #include <linux/module.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/slab.h>
  16
  17 #include <drm/drm_edid.h>
  18
  19 #include <video/omapdss.h>
  20 #include <video/omap-panel-data.h>
  21
  22 static const struct omap_video_timings dvic_default_timings = {
  23         .x_res          = 640,
  24         .y_res          = 480,
  25
  26         .pixelclock     = 23500000,
  27
  28         .hfp            = 48,
  29         .hsw            = 32,
  30         .hbp            = 80,
  31
  32         .vfp            = 3,
  33         .vsw            = 4,
  34         .vbp            = 7,
  35
  36         .vsync_level    = OMAPDSS_SIG_ACTIVE_HIGH,
  37         .hsync_level    = OMAPDSS_SIG_ACTIVE_HIGH,
  38         .data_pclk_edge = OMAPDSS_DRIVE_SIG_RISING_EDGE,
  39         .de_level       = OMAPDSS_SIG_ACTIVE_HIGH,
  40         .sync_pclk_edge = OMAPDSS_DRIVE_SIG_FALLING_EDGE,
  41 };
  42
  43 struct panel_drv_data {
  44         struct omap_dss_device dssdev;
  45         struct omap_dss_device *in;
  46
  47         struct omap_video_timings timings;
  48
  49         struct i2c_adapter *i2c_adapter;
  50 };
  51
  52 #define to_panel_data(x) container_of(x, struct panel_drv_data, dssdev)
  53
  54 static int dvic_connect(struct omap_dss_device *dssdev)
  55 {
  56         struct panel_drv_data *ddata = to_panel_data(dssdev);
  57         struct omap_dss_device *in = ddata->in;
  58         int r;
  59
  60         if (omapdss_device_is_connected(dssdev))
  61                 return 0;
  62
  63         r = in->ops.dvi->connect(in, dssdev);
  64         if (r)
  65                 return r;
  66
  67         return 0;
  68 }
  69
  70 static void dvic_disconnect(struct omap_dss_device *dssdev)
  71 {
  72         struct panel_drv_data *ddata = to_panel_data(dssdev);
  73         struct omap_dss_device *in = ddata->in;
  74
  75         if (!omapdss_device_is_connected(dssdev))
  76                 return;
  77
  78         in->ops.dvi->disconnect(in, dssdev);
  79 }
  80
  81 static int dvic_enable(struct omap_dss_device *dssdev)
  82 {
  83         struct panel_drv_data *ddata = to_panel_data(dssdev);
  84         struct omap_dss_device *in = ddata->in;
  85         int r;
  86
  87         if (!omapdss_device_is_connected(dssdev))
  88                 return -ENODEV;
  89
  90         if (omapdss_device_is_enabled(dssdev))
  91                 return 0;
  92
  93         in->ops.dvi->set_timings(in, &ddata->timings);
  94
  95         r = in->ops.dvi->enable(in);
  96         if (r)
  97                 return r;
  98
  99         dssdev->state = OMAP_DSS_DISPLAY_ACTIVE;
 100
 101         return 0;
 102 }
 103
 104 static void dvic_disable(struct omap_dss_device *dssdev)
 105 {
 106         struct panel_drv_data *ddata = to_panel_data(dssdev);
 107         struct omap_dss_device *in = ddata->in;
 108
 109         if (!omapdss_device_is_enabled(dssdev))
 110                 return;
 111
 112         in->ops.dvi->disable(in);
 113
 114         dssdev->state = OMAP_DSS_DISPLAY_DISABLED;
 115 }
 116
 117 static void dvic_set_timings(struct omap_dss_device *dssdev,
 118                 struct omap_video_timings *timings)
 119 {
 120         struct panel_drv_data *ddata = to_panel_data(dssdev);
 121         struct omap_dss_device *in = ddata->in;
 122
 123         ddata->timings = *timings;
 124         dssdev->panel.timings = *timings;
 125
 126         in->ops.dvi->set_timings(in, timings);
 127 }
 128
 129 static void dvic_get_timings(struct omap_dss_device *dssdev,
 130                 struct omap_video_timings *timings)
 131 {
 132         struct panel_drv_data *ddata = to_panel_data(dssdev);
 133
 134         *timings = ddata->timings;
 135 }
 136
 137 static int dvic_check_timings(struct omap_dss_device *dssdev,
 138                 struct omap_video_timings *timings)
 139 {
 140         struct panel_drv_data *ddata = to_panel_data(dssdev);
 141         struct omap_dss_device *in = ddata->in;
 142
 143         return in->ops.dvi->check_timings(in, timings);
 144 }
 145
 146 static int dvic_ddc_read(struct i2c_adapter *adapter,
 147                 unsigned char *buf, u16 count, u8 offset)
 148 {
 149         int r, retries;
 150
 151         for (retries = 3; retries > 0; retries--) {
 152                 struct i2c_msg msgs[] = {
 153                         {
 154                                 .addr   = DDC_ADDR,
 155                                 .flags  = 0,
 156                                 .len    = 1,
 157                                 .buf    = &offset,
 158                         }, {
 159                                 .addr   = DDC_ADDR,
 160                                 .flags  = I2C_M_RD,
 161                                 .len    = count,
 162                                 .buf    = buf,
 163                         }
 164                 };
 165
 166                 r = i2c_transfer(adapter, msgs, 2);
 167                 if (r == 2)
 168                         return 0;
 169
 170                 if (r != -EAGAIN)
 171                         break;
 172         }
 173
 174         return r < 0 ? r : -EIO;
 175 }
 176
 177 static int dvic_read_edid(struct omap_dss_device *dssdev,
 178                 u8 *edid, int len)
 179 {
 180         struct panel_drv_data *ddata = to_panel_data(dssdev);
 181         int r, l, bytes_read;
 182
 183         if (!ddata->i2c_adapter)
 184                 return -ENODEV;
 185
 186         l = min(EDID_LENGTH, len);
 187         r = dvic_ddc_read(ddata->i2c_adapter, edid, l, 0);
 188         if (r)
 189                 return r;
 190
 191         bytes_read = l;
 192
 193         /* if there are extensions, read second block */
 194         if (len > EDID_LENGTH && edid[0x7e] > 0) {
 195                 l = min(EDID_LENGTH, len - EDID_LENGTH);
 196
 197                 r = dvic_ddc_read(ddata->i2c_adapter, edid + EDID_LENGTH,
 198                                 l, EDID_LENGTH);
 199                 if (r)
 200                         return r;
 201
 202                 bytes_read += l;
 203         }
 204
 205         return bytes_read;
 206 }
 207
 208 static bool dvic_detect(struct omap_dss_device *dssdev)
 209 {
 210         struct panel_drv_data *ddata = to_panel_data(dssdev);
 211         unsigned char out;
 212         int r;
 213
 214         if (!ddata->i2c_adapter)
 215                 return true;
 216
 217         r = dvic_ddc_read(ddata->i2c_adapter, &out, 1, 0);
 218
 219         return r == 0;
 220 }
 221
 222 static struct omap_dss_driver dvic_driver = {
 223         .connect        = dvic_connect,
 224         .disconnect     = dvic_disconnect,
 225
 226         .enable         = dvic_enable,
 227         .disable        = dvic_disable,
 228
 229         .set_timings    = dvic_set_timings,
 230         .get_timings    = dvic_get_timings,
 231         .check_timings  = dvic_check_timings,
 232
 233         .get_resolution = omapdss_default_get_resolution,
 234
 235         .read_edid      = dvic_read_edid,
 236         .detect         = dvic_detect,
 237 };
 238
 239 static int dvic_probe_of(struct platform_device *pdev)
 240 {
 241         struct panel_drv_data *ddata = platform_get_drvdata(pdev);
 242         struct device_node *node = pdev->dev.of_node;
 243         struct omap_dss_device *in;
 244         struct device_node *adapter_node;
 245         struct i2c_adapter *adapter;
 246
 247         in = omapdss_of_find_source_for_first_ep(node);
 248         if (IS_ERR(in)) {
 249                 dev_err(&pdev->dev, "failed to find video source\n");
 250                 return PTR_ERR(in);
 251         }
 252
 253         ddata->in = in;
 254
 255         adapter_node = of_parse_phandle(node, "ddc-i2c-bus", 0);
 256         if (adapter_node) {
 257                 adapter = of_get_i2c_adapter_by_node(adapter_node);
 258                 if (adapter == NULL) {
 259                         dev_err(&pdev->dev, "failed to parse ddc-i2c-bus\n");
 260                         omap_dss_put_device(ddata->in);
 261                         return -EPROBE_DEFER;
 262                 }
 263
 264                 ddata->i2c_adapter = adapter;
 265         }
 266
 267         return 0;
 268 }
 269
 270 static int dvic_probe(struct platform_device *pdev)
 271 {
 272         struct panel_drv_data *ddata;
 273         struct omap_dss_device *dssdev;
 274         int r;
 275
 276         ddata = devm_kzalloc(&pdev->dev, sizeof(*ddata), GFP_KERNEL);
 277         if (!ddata)
 278                 return -ENOMEM;
 279
 280         platform_set_drvdata(pdev, ddata);
 281
 282         if (!pdev->dev.of_node)
 283                 return -ENODEV;
 284
 285         r = dvic_probe_of(pdev);
 286         if (r)
 287                 return r;
 288
 289         ddata->timings = dvic_default_timings;
 290
 291         dssdev = &ddata->dssdev;
 292         dssdev->driver = &dvic_driver;
 293         dssdev->dev = &pdev->dev;
 294         dssdev->type = OMAP_DISPLAY_TYPE_DVI;
 295         dssdev->owner = THIS_MODULE;
 296         dssdev->panel.timings = dvic_default_timings;
 297
 298         r = omapdss_register_display(dssdev);
 299         if (r) {
 300                 dev_err(&pdev->dev, "Failed to register panel\n");
 301                 goto err_reg;
 302         }
 303
 304         return 0;
 305
 306 err_reg:
 307         omap_dss_put_device(ddata->in);
 308
 309         i2c_put_adapter(ddata->i2c_adapter);
 310
 311         return r;
 312 }
 313
 314 static int __exit dvic_remove(struct platform_device *pdev)
 315 {
 316         struct panel_drv_data *ddata = platform_get_drvdata(pdev);
 317         struct omap_dss_device *dssdev = &ddata->dssdev;
 318         struct omap_dss_device *in = ddata->in;
 319
 320         omapdss_unregister_display(&ddata->dssdev);
 321
 322         dvic_disable(dssdev);
 323         dvic_disconnect(dssdev);
 324
 325         omap_dss_put_device(in);
 326
 327         i2c_put_adapter(ddata->i2c_adapter);
 328
 329         return 0;
 330 }
 331
 332 static const struct of_device_id dvic_of_match[] = {
 333         { .compatible = "omapdss,dvi-connector", },
 334         {},
 335 };
 336
 337 MODULE_DEVICE_TABLE(of, dvic_of_match);
 338
 339 static struct platform_driver dvi_connector_driver = {
 340         .probe  = dvic_probe,
 341         .remove = __exit_p(dvic_remove),
 342         .driver = {
 343                 .name   = "connector-dvi",
 344                 .of_match_table = dvic_of_match,
 345                 .suppress_bind_attrs = true,
 346         },
 347 };
 348
 349 module_platform_driver(dvi_connector_driver);
 350
 351 MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
 352 MODULE_DESCRIPTION("Generic DVI Connector driver");
 353 MODULE_LICENSE("GPL");