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