drivers/gpu/drm/i2c/sil164_drv.c

   1 /*
   2  * Copyright (C) 2010 Francisco Jerez.
   3  * All Rights Reserved.
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining
   6  * a copy of this software and associated documentation files (the
   7  * "Software"), to deal in the Software without restriction, including
   8  * without limitation the rights to use, copy, modify, merge, publish,
   9  * distribute, sublicense, and/or sell copies of the Software, and to
  10  * permit persons to whom the Software is furnished to do so, subject to
  11  * the following conditions:
  12  *
  13  * The above copyright notice and this permission notice (including the
  14  * next paragraph) shall be included in all copies or substantial
  15  * portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  18  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  19  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  20  * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
  21  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  22  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  23  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  24  *
  25  */
  26
  27 #include <linux/module.h>
  28
  29 #include <drm/drmP.h>
  30 #include <drm/drm_crtc_helper.h>
  31 #include <drm/drm_encoder_slave.h>
  32 #include <drm/i2c/sil164.h>
  33
  34 struct sil164_priv {
  35         struct sil164_encoder_params config;
  36         struct i2c_client *duallink_slave;
  37
  38         uint8_t saved_state[0x10];
  39         uint8_t saved_slave_state[0x10];
  40 };
  41
  42 #define to_sil164_priv(x) \
  43         ((struct sil164_priv *)to_encoder_slave(x)->slave_priv)
  44
  45 #define sil164_dbg(client, format, ...) do {                            \
  46                 if (drm_debug & DRM_UT_KMS)                             \
  47                         dev_printk(KERN_DEBUG, &client->dev,            \
  48                                    "%s: " format, __func__, ## __VA_ARGS__); \
  49         } while (0)
  50 #define sil164_info(client, format, ...)                \
  51         dev_info(&client->dev, format, __VA_ARGS__)
  52 #define sil164_err(client, format, ...)                 \
  53         dev_err(&client->dev, format, __VA_ARGS__)
  54
  55 #define SIL164_I2C_ADDR_MASTER                  0x38
  56 #define SIL164_I2C_ADDR_SLAVE                   0x39
  57
  58 /* HW register definitions */
  59
  60 #define SIL164_VENDOR_LO                        0x0
  61 #define SIL164_VENDOR_HI                        0x1
  62 #define SIL164_DEVICE_LO                        0x2
  63 #define SIL164_DEVICE_HI                        0x3
  64 #define SIL164_REVISION                         0x4
  65 #define SIL164_FREQ_MIN                         0x6
  66 #define SIL164_FREQ_MAX                         0x7
  67 #define SIL164_CONTROL0                         0x8
  68 #  define SIL164_CONTROL0_POWER_ON              0x01
  69 #  define SIL164_CONTROL0_EDGE_RISING           0x02
  70 #  define SIL164_CONTROL0_INPUT_24BIT           0x04
  71 #  define SIL164_CONTROL0_DUAL_EDGE             0x08
  72 #  define SIL164_CONTROL0_HSYNC_ON              0x10
  73 #  define SIL164_CONTROL0_VSYNC_ON              0x20
  74 #define SIL164_DETECT                           0x9
  75 #  define SIL164_DETECT_INTR_STAT               0x01
  76 #  define SIL164_DETECT_HOTPLUG_STAT            0x02
  77 #  define SIL164_DETECT_RECEIVER_STAT           0x04
  78 #  define SIL164_DETECT_INTR_MODE_RECEIVER      0x00
  79 #  define SIL164_DETECT_INTR_MODE_HOTPLUG       0x08
  80 #  define SIL164_DETECT_OUT_MODE_HIGH           0x00
  81 #  define SIL164_DETECT_OUT_MODE_INTR           0x10
  82 #  define SIL164_DETECT_OUT_MODE_RECEIVER       0x20
  83 #  define SIL164_DETECT_OUT_MODE_HOTPLUG        0x30
  84 #  define SIL164_DETECT_VSWING_STAT             0x80
  85 #define SIL164_CONTROL1                         0xa
  86 #  define SIL164_CONTROL1_DESKEW_ENABLE         0x10
  87 #  define SIL164_CONTROL1_DESKEW_INCR_SHIFT     5
  88 #define SIL164_GPIO                             0xb
  89 #define SIL164_CONTROL2                         0xc
  90 #  define SIL164_CONTROL2_FILTER_ENABLE         0x01
  91 #  define SIL164_CONTROL2_FILTER_SETTING_SHIFT  1
  92 #  define SIL164_CONTROL2_DUALLINK_MASTER       0x40
  93 #  define SIL164_CONTROL2_SYNC_CONT             0x80
  94 #define SIL164_DUALLINK                         0xd
  95 #  define SIL164_DUALLINK_ENABLE                0x10
  96 #  define SIL164_DUALLINK_SKEW_SHIFT            5
  97 #define SIL164_PLLZONE                          0xe
  98 #  define SIL164_PLLZONE_STAT                   0x08
  99 #  define SIL164_PLLZONE_FORCE_ON               0x10
 100 #  define SIL164_PLLZONE_FORCE_HIGH             0x20
 101
 102 /* HW access functions */
 103
 104 static void
 105 sil164_write(struct i2c_client *client, uint8_t addr, uint8_t val)
 106 {
 107         uint8_t buf[] = {addr, val};
 108         int ret;
 109
 110         ret = i2c_master_send(client, buf, ARRAY_SIZE(buf));
 111         if (ret < 0)
 112                 sil164_err(client, "Error %d writing to subaddress 0x%x\n",
 113                            ret, addr);
 114 }
 115
 116 static uint8_t
 117 sil164_read(struct i2c_client *client, uint8_t addr)
 118 {
 119         uint8_t val;
 120         int ret;
 121
 122         ret = i2c_master_send(client, &addr, sizeof(addr));
 123         if (ret < 0)
 124                 goto fail;
 125
 126         ret = i2c_master_recv(client, &val, sizeof(val));
 127         if (ret < 0)
 128                 goto fail;
 129
 130         return val;
 131
 132 fail:
 133         sil164_err(client, "Error %d reading from subaddress 0x%x\n",
 134                    ret, addr);
 135         return 0;
 136 }
 137
 138 static void
 139 sil164_save_state(struct i2c_client *client, uint8_t *state)
 140 {
 141         int i;
 142
 143         for (i = 0x8; i <= 0xe; i++)
 144                 state[i] = sil164_read(client, i);
 145 }
 146
 147 static void
 148 sil164_restore_state(struct i2c_client *client, uint8_t *state)
 149 {
 150         int i;
 151
 152         for (i = 0x8; i <= 0xe; i++)
 153                 sil164_write(client, i, state[i]);
 154 }
 155
 156 static void
 157 sil164_set_power_state(struct i2c_client *client, bool on)
 158 {
 159         uint8_t control0 = sil164_read(client, SIL164_CONTROL0);
 160
 161         if (on)
 162                 control0 |= SIL164_CONTROL0_POWER_ON;
 163         else
 164                 control0 &= ~SIL164_CONTROL0_POWER_ON;
 165
 166         sil164_write(client, SIL164_CONTROL0, control0);
 167 }
 168
 169 static void
 170 sil164_init_state(struct i2c_client *client,
 171                   struct sil164_encoder_params *config,
 172                   bool duallink)
 173 {
 174         sil164_write(client, SIL164_CONTROL0,
 175                      SIL164_CONTROL0_HSYNC_ON |
 176                      SIL164_CONTROL0_VSYNC_ON |
 177                      (config->input_edge ? SIL164_CONTROL0_EDGE_RISING : 0) |
 178                      (config->input_width ? SIL164_CONTROL0_INPUT_24BIT : 0) |
 179                      (config->input_dual ? SIL164_CONTROL0_DUAL_EDGE : 0));
 180
 181         sil164_write(client, SIL164_DETECT,
 182                      SIL164_DETECT_INTR_STAT |
 183                      SIL164_DETECT_OUT_MODE_RECEIVER);
 184
 185         sil164_write(client, SIL164_CONTROL1,
 186                      (config->input_skew ? SIL164_CONTROL1_DESKEW_ENABLE : 0) |
 187                      (((config->input_skew + 4) & 0x7)
 188                       << SIL164_CONTROL1_DESKEW_INCR_SHIFT));
 189
 190         sil164_write(client, SIL164_CONTROL2,
 191                      SIL164_CONTROL2_SYNC_CONT |
 192                      (config->pll_filter ? 0 : SIL164_CONTROL2_FILTER_ENABLE) |
 193                      (4 << SIL164_CONTROL2_FILTER_SETTING_SHIFT));
 194
 195         sil164_write(client, SIL164_PLLZONE, 0);
 196
 197         if (duallink)
 198                 sil164_write(client, SIL164_DUALLINK,
 199                              SIL164_DUALLINK_ENABLE |
 200                              (((config->duallink_skew + 4) & 0x7)
 201                               << SIL164_DUALLINK_SKEW_SHIFT));
 202         else
 203                 sil164_write(client, SIL164_DUALLINK, 0);
 204 }
 205
 206 /* DRM encoder functions */
 207
 208 static void
 209 sil164_encoder_set_config(struct drm_encoder *encoder, void *params)
 210 {
 211         struct sil164_priv *priv = to_sil164_priv(encoder);
 212
 213         priv->config = *(struct sil164_encoder_params *)params;
 214 }
 215
 216 static void
 217 sil164_encoder_dpms(struct drm_encoder *encoder, int mode)
 218 {
 219         struct sil164_priv *priv = to_sil164_priv(encoder);
 220         bool on = (mode == DRM_MODE_DPMS_ON);
 221         bool duallink = (on && encoder->crtc->mode.clock > 165000);
 222
 223         sil164_set_power_state(drm_i2c_encoder_get_client(encoder), on);
 224
 225         if (priv->duallink_slave)
 226                 sil164_set_power_state(priv->duallink_slave, duallink);
 227 }
 228
 229 static void
 230 sil164_encoder_save(struct drm_encoder *encoder)
 231 {
 232         struct sil164_priv *priv = to_sil164_priv(encoder);
 233
 234         sil164_save_state(drm_i2c_encoder_get_client(encoder),
 235                           priv->saved_state);
 236
 237         if (priv->duallink_slave)
 238                 sil164_save_state(priv->duallink_slave,
 239                                   priv->saved_slave_state);
 240 }
 241
 242 static void
 243 sil164_encoder_restore(struct drm_encoder *encoder)
 244 {
 245         struct sil164_priv *priv = to_sil164_priv(encoder);
 246
 247         sil164_restore_state(drm_i2c_encoder_get_client(encoder),
 248                              priv->saved_state);
 249
 250         if (priv->duallink_slave)
 251                 sil164_restore_state(priv->duallink_slave,
 252                                      priv->saved_slave_state);
 253 }
 254
 255 static int
 256 sil164_encoder_mode_valid(struct drm_encoder *encoder,
 257                           struct drm_display_mode *mode)
 258 {
 259         struct sil164_priv *priv = to_sil164_priv(encoder);
 260
 261         if (mode->clock < 32000)
 262                 return MODE_CLOCK_LOW;
 263
 264         if (mode->clock > 330000 ||
 265             (mode->clock > 165000 && !priv->duallink_slave))
 266                 return MODE_CLOCK_HIGH;
 267
 268         return MODE_OK;
 269 }
 270
 271 static void
 272 sil164_encoder_mode_set(struct drm_encoder *encoder,
 273                         struct drm_display_mode *mode,
 274                         struct drm_display_mode *adjusted_mode)
 275 {
 276         struct sil164_priv *priv = to_sil164_priv(encoder);
 277         bool duallink = adjusted_mode->clock > 165000;
 278
 279         sil164_init_state(drm_i2c_encoder_get_client(encoder),
 280                           &priv->config, duallink);
 281
 282         if (priv->duallink_slave)
 283                 sil164_init_state(priv->duallink_slave,
 284                                   &priv->config, duallink);
 285
 286         sil164_encoder_dpms(encoder, DRM_MODE_DPMS_ON);
 287 }
 288
 289 static enum drm_connector_status
 290 sil164_encoder_detect(struct drm_encoder *encoder,
 291                       struct drm_connector *connector)
 292 {
 293         struct i2c_client *client = drm_i2c_encoder_get_client(encoder);
 294
 295         if (sil164_read(client, SIL164_DETECT) & SIL164_DETECT_HOTPLUG_STAT)
 296                 return connector_status_connected;
 297         else
 298                 return connector_status_disconnected;
 299 }
 300
 301 static int
 302 sil164_encoder_get_modes(struct drm_encoder *encoder,
 303                          struct drm_connector *connector)
 304 {
 305         return 0;
 306 }
 307
 308 static int
 309 sil164_encoder_create_resources(struct drm_encoder *encoder,
 310                                 struct drm_connector *connector)
 311 {
 312         return 0;
 313 }
 314
 315 static int
 316 sil164_encoder_set_property(struct drm_encoder *encoder,
 317                             struct drm_connector *connector,
 318                             struct drm_property *property,
 319                             uint64_t val)
 320 {
 321         return 0;
 322 }
 323
 324 static void
 325 sil164_encoder_destroy(struct drm_encoder *encoder)
 326 {
 327         struct sil164_priv *priv = to_sil164_priv(encoder);
 328
 329         if (priv->duallink_slave)
 330                 i2c_unregister_device(priv->duallink_slave);
 331
 332         kfree(priv);
 333         drm_i2c_encoder_destroy(encoder);
 334 }
 335
 336 static const struct drm_encoder_slave_funcs sil164_encoder_funcs = {
 337         .set_config = sil164_encoder_set_config,
 338         .destroy = sil164_encoder_destroy,
 339         .dpms = sil164_encoder_dpms,
 340         .save = sil164_encoder_save,
 341         .restore = sil164_encoder_restore,
 342         .mode_valid = sil164_encoder_mode_valid,
 343         .mode_set = sil164_encoder_mode_set,
 344         .detect = sil164_encoder_detect,
 345         .get_modes = sil164_encoder_get_modes,
 346         .create_resources = sil164_encoder_create_resources,
 347         .set_property = sil164_encoder_set_property,
 348 };
 349
 350 /* I2C driver functions */
 351
 352 static int
 353 sil164_probe(struct i2c_client *client, const struct i2c_device_id *id)
 354 {
 355         int vendor = sil164_read(client, SIL164_VENDOR_HI) << 8 |
 356                 sil164_read(client, SIL164_VENDOR_LO);
 357         int device = sil164_read(client, SIL164_DEVICE_HI) << 8 |
 358                 sil164_read(client, SIL164_DEVICE_LO);
 359         int rev = sil164_read(client, SIL164_REVISION);
 360
 361         if (vendor != 0x1 || device != 0x6) {
 362                 sil164_dbg(client, "Unknown device %x:%x.%x\n",
 363                            vendor, device, rev);
 364                 return -ENODEV;
 365         }
 366
 367         sil164_info(client, "Detected device %x:%x.%x\n",
 368                     vendor, device, rev);
 369
 370         return 0;
 371 }
 372
 373 static int
 374 sil164_remove(struct i2c_client *client)
 375 {
 376         return 0;
 377 }
 378
 379 static struct i2c_client *
 380 sil164_detect_slave(struct i2c_client *client)
 381 {
 382         struct i2c_adapter *adap = client->adapter;
 383         struct i2c_msg msg = {
 384                 .addr = SIL164_I2C_ADDR_SLAVE,
 385                 .len = 0,
 386         };
 387         const struct i2c_board_info info = {
 388                 I2C_BOARD_INFO("sil164", SIL164_I2C_ADDR_SLAVE)
 389         };
 390
 391         if (i2c_transfer(adap, &msg, 1) != 1) {
 392                 sil164_dbg(adap, "No dual-link slave found.");
 393                 return NULL;
 394         }
 395
 396         return i2c_new_device(adap, &info);
 397 }
 398
 399 static int
 400 sil164_encoder_init(struct i2c_client *client,
 401                     struct drm_device *dev,
 402                     struct drm_encoder_slave *encoder)
 403 {
 404         struct sil164_priv *priv;
 405
 406         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 407         if (!priv)
 408                 return -ENOMEM;
 409
 410         encoder->slave_priv = priv;
 411         encoder->slave_funcs = &sil164_encoder_funcs;
 412
 413         priv->duallink_slave = sil164_detect_slave(client);
 414
 415         return 0;
 416 }
 417
 418 static struct i2c_device_id sil164_ids[] = {
 419         { "sil164", 0 },
 420         { }
 421 };
 422 MODULE_DEVICE_TABLE(i2c, sil164_ids);
 423
 424 static struct drm_i2c_encoder_driver sil164_driver = {
 425         .i2c_driver = {
 426                 .probe = sil164_probe,
 427                 .remove = sil164_remove,
 428                 .driver = {
 429                         .name = "sil164",
 430                 },
 431                 .id_table = sil164_ids,
 432         },
 433         .encoder_init = sil164_encoder_init,
 434 };
 435
 436 /* Module initialization */
 437
 438 static int __init
 439 sil164_init(void)
 440 {
 441         return drm_i2c_encoder_register(THIS_MODULE, &sil164_driver);
 442 }
 443
 444 static void __exit
 445 sil164_exit(void)
 446 {
 447         drm_i2c_encoder_unregister(&sil164_driver);
 448 }
 449
 450 MODULE_AUTHOR("Francisco Jerez <currojerez@riseup.net>");
 451 MODULE_DESCRIPTION("Silicon Image sil164 TMDS transmitter driver");
 452 MODULE_LICENSE("GPL and additional rights");
 453
 454 module_init(sil164_init);
 455 module_exit(sil164_exit);