drivers/video/via/dvi.c

   1 /*
   2  * Copyright 1998-2008 VIA Technologies, Inc. All Rights Reserved.
   3  * Copyright 2001-2008 S3 Graphics, Inc. All Rights Reserved.
   4
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public
   7  * License as published by the Free Software Foundation;
   8  * either version 2, or (at your option) any later version.
   9
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTIES OR REPRESENTATIONS; without even
  12  * the implied warranty of MERCHANTABILITY or FITNESS FOR
  13  * A PARTICULAR PURPOSE.See the GNU General Public License
  14  * for more details.
  15
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc.,
  19  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  20  */
  21 #include <linux/via-core.h>
  22 #include <linux/via_i2c.h>
  23 #include "global.h"
  24
  25 static void tmds_register_write(int index, u8 data);
  26 static int tmds_register_read(int index);
  27 static int tmds_register_read_bytes(int index, u8 *buff, int buff_len);
  28 static void __devinit dvi_get_panel_size_from_DDCv1(
  29         struct tmds_chip_information *tmds_chip,
  30         struct tmds_setting_information *tmds_setting);
  31 static void __devinit dvi_get_panel_size_from_DDCv2(
  32         struct tmds_chip_information *tmds_chip,
  33         struct tmds_setting_information *tmds_setting);
  34 static int viafb_dvi_query_EDID(void);
  35
  36 static int check_tmds_chip(int device_id_subaddr, int device_id)
  37 {
  38         if (tmds_register_read(device_id_subaddr) == device_id)
  39                 return OK;
  40         else
  41                 return FAIL;
  42 }
  43
  44 void __devinit viafb_init_dvi_size(struct tmds_chip_information *tmds_chip,
  45         struct tmds_setting_information *tmds_setting)
  46 {
  47         DEBUG_MSG(KERN_INFO "viafb_init_dvi_size()\n");
  48
  49         viafb_dvi_sense();
  50         switch (viafb_dvi_query_EDID()) {
  51         case 1:
  52                 dvi_get_panel_size_from_DDCv1(tmds_chip, tmds_setting);
  53                 break;
  54         case 2:
  55                 dvi_get_panel_size_from_DDCv2(tmds_chip, tmds_setting);
  56                 break;
  57         default:
  58                 printk(KERN_WARNING "viafb_init_dvi_size: DVI panel size undetected!\n");
  59                 break;
  60         }
  61
  62         return;
  63 }
  64
  65 int __devinit viafb_tmds_trasmitter_identify(void)
  66 {
  67         unsigned char sr2a = 0, sr1e = 0, sr3e = 0;
  68
  69         /* Turn on ouputting pad */
  70         switch (viaparinfo->chip_info->gfx_chip_name) {
  71         case UNICHROME_K8M890:
  72             /*=* DFP Low Pad on *=*/
  73                 sr2a = viafb_read_reg(VIASR, SR2A);
  74                 viafb_write_reg_mask(SR2A, VIASR, 0x03, BIT0 + BIT1);
  75                 break;
  76
  77         case UNICHROME_P4M900:
  78         case UNICHROME_P4M890:
  79                 /* DFP Low Pad on */
  80                 sr2a = viafb_read_reg(VIASR, SR2A);
  81                 viafb_write_reg_mask(SR2A, VIASR, 0x03, BIT0 + BIT1);
  82                 /* DVP0 Pad on */
  83                 sr1e = viafb_read_reg(VIASR, SR1E);
  84                 viafb_write_reg_mask(SR1E, VIASR, 0xC0, BIT6 + BIT7);
  85                 break;
  86
  87         default:
  88             /* DVP0/DVP1 Pad on */
  89                 sr1e = viafb_read_reg(VIASR, SR1E);
  90                 viafb_write_reg_mask(SR1E, VIASR, 0xF0, BIT4 +
  91                         BIT5 + BIT6 + BIT7);
  92             /* SR3E[1]Multi-function selection:
  93             0 = Emulate I2C and DDC bus by GPIO2/3/4. */
  94                 sr3e = viafb_read_reg(VIASR, SR3E);
  95                 viafb_write_reg_mask(SR3E, VIASR, 0x0, BIT5);
  96                 break;
  97         }
  98
  99         /* Check for VT1632: */
 100         viaparinfo->chip_info->tmds_chip_info.tmds_chip_name = VT1632_TMDS;
 101         viaparinfo->chip_info->
 102                 tmds_chip_info.tmds_chip_slave_addr = VT1632_TMDS_I2C_ADDR;
 103         viaparinfo->chip_info->tmds_chip_info.i2c_port = VIA_PORT_31;
 104         if (check_tmds_chip(VT1632_DEVICE_ID_REG, VT1632_DEVICE_ID) != FAIL) {
 105                 /*
 106                  * Currently only support 12bits,dual edge,add 24bits mode later
 107                  */
 108                 tmds_register_write(0x08, 0x3b);
 109
 110                 DEBUG_MSG(KERN_INFO "\n VT1632 TMDS ! \n");
 111                 DEBUG_MSG(KERN_INFO "\n %2d",
 112                           viaparinfo->chip_info->tmds_chip_info.tmds_chip_name);
 113                 DEBUG_MSG(KERN_INFO "\n %2d",
 114                           viaparinfo->chip_info->tmds_chip_info.i2c_port);
 115                 return OK;
 116         } else {
 117                 viaparinfo->chip_info->tmds_chip_info.i2c_port = VIA_PORT_2C;
 118                 if (check_tmds_chip(VT1632_DEVICE_ID_REG, VT1632_DEVICE_ID)
 119                     != FAIL) {
 120                         tmds_register_write(0x08, 0x3b);
 121                         DEBUG_MSG(KERN_INFO "\n VT1632 TMDS ! \n");
 122                         DEBUG_MSG(KERN_INFO "\n %2d",
 123                                   viaparinfo->chip_info->
 124                                   tmds_chip_info.tmds_chip_name);
 125                         DEBUG_MSG(KERN_INFO "\n %2d",
 126                                   viaparinfo->chip_info->
 127                                   tmds_chip_info.i2c_port);
 128                         return OK;
 129                 }
 130         }
 131
 132         viaparinfo->chip_info->tmds_chip_info.tmds_chip_name = INTEGRATED_TMDS;
 133
 134         if ((viaparinfo->chip_info->gfx_chip_name == UNICHROME_CX700) &&
 135             ((viafb_display_hardware_layout == HW_LAYOUT_DVI_ONLY) ||
 136              (viafb_display_hardware_layout == HW_LAYOUT_LCD_DVI))) {
 137                 DEBUG_MSG(KERN_INFO "\n Integrated TMDS ! \n");
 138                 return OK;
 139         }
 140
 141         switch (viaparinfo->chip_info->gfx_chip_name) {
 142         case UNICHROME_K8M890:
 143                 viafb_write_reg(SR2A, VIASR, sr2a);
 144                 break;
 145
 146         case UNICHROME_P4M900:
 147         case UNICHROME_P4M890:
 148                 viafb_write_reg(SR2A, VIASR, sr2a);
 149                 viafb_write_reg(SR1E, VIASR, sr1e);
 150                 break;
 151
 152         default:
 153                 viafb_write_reg(SR1E, VIASR, sr1e);
 154                 viafb_write_reg(SR3E, VIASR, sr3e);
 155                 break;
 156         }
 157
 158         viaparinfo->chip_info->
 159                 tmds_chip_info.tmds_chip_name = NON_TMDS_TRANSMITTER;
 160         viaparinfo->chip_info->tmds_chip_info.
 161                 tmds_chip_slave_addr = VT1632_TMDS_I2C_ADDR;
 162         return FAIL;
 163 }
 164
 165 static void tmds_register_write(int index, u8 data)
 166 {
 167         viafb_i2c_writebyte(viaparinfo->chip_info->tmds_chip_info.i2c_port,
 168                             viaparinfo->chip_info->tmds_chip_info.tmds_chip_slave_addr,
 169                             index, data);
 170 }
 171
 172 static int tmds_register_read(int index)
 173 {
 174         u8 data;
 175
 176         viafb_i2c_readbyte(viaparinfo->chip_info->tmds_chip_info.i2c_port,
 177                            (u8) viaparinfo->chip_info->tmds_chip_info.tmds_chip_slave_addr,
 178                            (u8) index, &data);
 179         return data;
 180 }
 181
 182 static int tmds_register_read_bytes(int index, u8 *buff, int buff_len)
 183 {
 184         viafb_i2c_readbytes(viaparinfo->chip_info->tmds_chip_info.i2c_port,
 185                             (u8) viaparinfo->chip_info->tmds_chip_info.tmds_chip_slave_addr,
 186                             (u8) index, buff, buff_len);
 187         return 0;
 188 }
 189
 190 /* DVI Set Mode */
 191 void viafb_dvi_set_mode(struct VideoModeTable *mode, int mode_bpp,
 192         int set_iga)
 193 {
 194         struct VideoModeTable *rb_mode;
 195         struct crt_mode_table *pDviTiming;
 196         unsigned long desirePixelClock, maxPixelClock;
 197         pDviTiming = mode->crtc;
 198         desirePixelClock = pDviTiming->clk / 1000000;
 199         maxPixelClock = (unsigned long)viaparinfo->
 200                 tmds_setting_info->max_pixel_clock;
 201
 202         DEBUG_MSG(KERN_INFO "\nDVI_set_mode!!\n");
 203
 204         if ((maxPixelClock != 0) && (desirePixelClock > maxPixelClock)) {
 205                 rb_mode = viafb_get_rb_mode(mode->crtc[0].crtc.hor_addr,
 206                         mode->crtc[0].crtc.ver_addr);
 207                 if (rb_mode) {
 208                         mode = rb_mode;
 209                         pDviTiming = rb_mode->crtc;
 210                 }
 211         }
 212         viafb_fill_crtc_timing(pDviTiming, mode, mode_bpp / 8, set_iga);
 213 }
 214
 215 /* Sense DVI Connector */
 216 int viafb_dvi_sense(void)
 217 {
 218         u8 RegSR1E = 0, RegSR3E = 0, RegCR6B = 0, RegCR91 = 0,
 219                 RegCR93 = 0, RegCR9B = 0, data;
 220         int ret = false;
 221
 222         DEBUG_MSG(KERN_INFO "viafb_dvi_sense!!\n");
 223
 224         if (viaparinfo->chip_info->gfx_chip_name == UNICHROME_CLE266) {
 225                 /* DI1 Pad on */
 226                 RegSR1E = viafb_read_reg(VIASR, SR1E);
 227                 viafb_write_reg(SR1E, VIASR, RegSR1E | 0x30);
 228
 229                 /* CR6B[0]VCK Input Selection: 1 = External clock. */
 230                 RegCR6B = viafb_read_reg(VIACR, CR6B);
 231                 viafb_write_reg(CR6B, VIACR, RegCR6B | 0x08);
 232
 233                 /* CR91[4] VDD On [3] Data On [2] VEE On [1] Back Light Off
 234                    [0] Software Control Power Sequence */
 235                 RegCR91 = viafb_read_reg(VIACR, CR91);
 236                 viafb_write_reg(CR91, VIACR, 0x1D);
 237
 238                 /* CR93[7] DI1 Data Source Selection: 1 = DSP2.
 239                    CR93[5] DI1 Clock Source: 1 = internal.
 240                    CR93[4] DI1 Clock Polarity.
 241                    CR93[3:1] DI1 Clock Adjust. CR93[0] DI1 enable */
 242                 RegCR93 = viafb_read_reg(VIACR, CR93);
 243                 viafb_write_reg(CR93, VIACR, 0x01);
 244         } else {
 245                 /* DVP0/DVP1 Pad on */
 246                 RegSR1E = viafb_read_reg(VIASR, SR1E);
 247                 viafb_write_reg(SR1E, VIASR, RegSR1E | 0xF0);
 248
 249                 /* SR3E[1]Multi-function selection:
 250                    0 = Emulate I2C and DDC bus by GPIO2/3/4. */
 251                 RegSR3E = viafb_read_reg(VIASR, SR3E);
 252                 viafb_write_reg(SR3E, VIASR, RegSR3E & (~0x20));
 253
 254                 /* CR91[4] VDD On [3] Data On [2] VEE On [1] Back Light Off
 255                    [0] Software Control Power Sequence */
 256                 RegCR91 = viafb_read_reg(VIACR, CR91);
 257                 viafb_write_reg(CR91, VIACR, 0x1D);
 258
 259                 /*CR9B[4] DVP1 Data Source Selection: 1 = From secondary
 260                 display.CR9B[2:0] DVP1 Clock Adjust */
 261                 RegCR9B = viafb_read_reg(VIACR, CR9B);
 262                 viafb_write_reg(CR9B, VIACR, 0x01);
 263         }
 264
 265         data = (u8) tmds_register_read(0x09);
 266         if (data & 0x04)
 267                 ret = true;
 268
 269         if (ret == false) {
 270                 if (viafb_dvi_query_EDID())
 271                         ret = true;
 272         }
 273
 274         /* Restore status */
 275         viafb_write_reg(SR1E, VIASR, RegSR1E);
 276         viafb_write_reg(CR91, VIACR, RegCR91);
 277         if (viaparinfo->chip_info->gfx_chip_name == UNICHROME_CLE266) {
 278                 viafb_write_reg(CR6B, VIACR, RegCR6B);
 279                 viafb_write_reg(CR93, VIACR, RegCR93);
 280         } else {
 281                 viafb_write_reg(SR3E, VIASR, RegSR3E);
 282                 viafb_write_reg(CR9B, VIACR, RegCR9B);
 283         }
 284
 285         return ret;
 286 }
 287
 288 /* Query Flat Panel's EDID Table Version Through DVI Connector */
 289 static int viafb_dvi_query_EDID(void)
 290 {
 291         u8 data0, data1;
 292         int restore;
 293
 294         DEBUG_MSG(KERN_INFO "viafb_dvi_query_EDID!!\n");
 295
 296         restore = viaparinfo->chip_info->tmds_chip_info.tmds_chip_slave_addr;
 297         viaparinfo->chip_info->tmds_chip_info.tmds_chip_slave_addr = 0xA0;
 298
 299         data0 = (u8) tmds_register_read(0x00);
 300         data1 = (u8) tmds_register_read(0x01);
 301         if ((data0 == 0) && (data1 == 0xFF)) {
 302                 viaparinfo->chip_info->
 303                         tmds_chip_info.tmds_chip_slave_addr = restore;
 304                 return EDID_VERSION_1;  /* Found EDID1 Table */
 305         }
 306
 307         data0 = (u8) tmds_register_read(0x00);
 308         viaparinfo->chip_info->tmds_chip_info.tmds_chip_slave_addr = restore;
 309         if (data0 == 0x20)
 310                 return EDID_VERSION_2;  /* Found EDID2 Table */
 311         else
 312                 return false;
 313 }
 314
 315 /* Get Panel Size Using EDID1 Table */
 316 static void __devinit dvi_get_panel_size_from_DDCv1(
 317         struct tmds_chip_information *tmds_chip,
 318         struct tmds_setting_information *tmds_setting)
 319 {
 320         int i, max_h = 0, tmp, restore;
 321         unsigned char rData;
 322         unsigned char EDID_DATA[18];
 323
 324         DEBUG_MSG(KERN_INFO "\n dvi_get_panel_size_from_DDCv1 \n");
 325
 326         restore = tmds_chip->tmds_chip_slave_addr;
 327         tmds_chip->tmds_chip_slave_addr = 0xA0;
 328
 329         rData = tmds_register_read(0x23);
 330         if (rData & 0x3C)
 331                 max_h = 640;
 332         if (rData & 0xC0)
 333                 max_h = 720;
 334         if (rData & 0x03)
 335                 max_h = 800;
 336
 337         rData = tmds_register_read(0x24);
 338         if (rData & 0xC0)
 339                 max_h = 800;
 340         if (rData & 0x1E)
 341                 max_h = 1024;
 342         if (rData & 0x01)
 343                 max_h = 1280;
 344
 345         for (i = 0x25; i < 0x6D; i++) {
 346                 switch (i) {
 347                 case 0x26:
 348                 case 0x28:
 349                 case 0x2A:
 350                 case 0x2C:
 351                 case 0x2E:
 352                 case 0x30:
 353                 case 0x32:
 354                 case 0x34:
 355                         rData = tmds_register_read(i);
 356                         if (rData == 1)
 357                                 break;
 358                         /* data = (data + 31) * 8 */
 359                         tmp = (rData + 31) << 3;
 360                         if (tmp > max_h)
 361                                 max_h = tmp;
 362                         break;
 363
 364                 case 0x36:
 365                 case 0x48:
 366                 case 0x5A:
 367                 case 0x6C:
 368                         tmds_register_read_bytes(i, EDID_DATA, 10);
 369                         if (!(EDID_DATA[0] || EDID_DATA[1])) {
 370                                 /* The first two byte must be zero. */
 371                                 if (EDID_DATA[3] == 0xFD) {
 372                                         /* To get max pixel clock. */
 373                                         tmds_setting->max_pixel_clock =
 374                                                 EDID_DATA[9] * 10;
 375                                 }
 376                         }
 377                         break;
 378
 379                 default:
 380                         break;
 381                 }
 382         }
 383
 384         tmds_setting->max_hres = max_h;
 385         switch (max_h) {
 386         case 640:
 387                 tmds_setting->max_vres = 480;
 388                 break;
 389         case 800:
 390                 tmds_setting->max_vres = 600;
 391                 break;
 392         case 1024:
 393                 tmds_setting->max_vres = 768;
 394                 break;
 395         case 1280:
 396                 tmds_setting->max_vres = 1024;
 397                 break;
 398         case 1400:
 399                 tmds_setting->max_vres = 1050;
 400                 break;
 401         case 1440:
 402                 tmds_setting->max_vres = 1050;
 403                 break;
 404         case 1600:
 405                 tmds_setting->max_vres = 1200;
 406                 break;
 407         case 1920:
 408                 tmds_setting->max_vres = 1080;
 409                 break;
 410         default:
 411                 DEBUG_MSG(KERN_INFO "Unknown panel size max resolution = %d ! "
 412                                          "set default panel size.\n", max_h);
 413                 break;
 414         }
 415
 416         DEBUG_MSG(KERN_INFO "DVI max pixelclock = %d\n",
 417                 tmds_setting->max_pixel_clock);
 418         tmds_chip->tmds_chip_slave_addr = restore;
 419 }
 420
 421 /* Get Panel Size Using EDID2 Table */
 422 static void __devinit dvi_get_panel_size_from_DDCv2(
 423         struct tmds_chip_information *tmds_chip,
 424         struct tmds_setting_information *tmds_setting)
 425 {
 426         int restore;
 427         unsigned char R_Buffer[2];
 428
 429         DEBUG_MSG(KERN_INFO "\n dvi_get_panel_size_from_DDCv2 \n");
 430
 431         restore = tmds_chip->tmds_chip_slave_addr;
 432         tmds_chip->tmds_chip_slave_addr = 0xA2;
 433
 434         /* Horizontal: 0x76, 0x77 */
 435         tmds_register_read_bytes(0x76, R_Buffer, 2);
 436         tmds_setting->max_hres = R_Buffer[0] + (R_Buffer[1] << 8);
 437
 438         switch (tmds_setting->max_hres) {
 439         case 640:
 440                 tmds_setting->max_vres = 480;
 441                 break;
 442         case 800:
 443                 tmds_setting->max_vres = 600;
 444                 break;
 445         case 1024:
 446                 tmds_setting->max_vres = 768;
 447                 break;
 448         case 1280:
 449                 tmds_setting->max_vres = 1024;
 450                 break;
 451         case 1400:
 452                 tmds_setting->max_vres = 1050;
 453                 break;
 454         case 1440:
 455                 tmds_setting->max_vres = 1050;
 456                 break;
 457         case 1600:
 458                 tmds_setting->max_vres = 1200;
 459                 break;
 460         default:
 461                 DEBUG_MSG(KERN_INFO "Unknown panel size max resolution = %d! "
 462                         "set default panel size.\n", tmds_setting->max_hres);
 463                 break;
 464         }
 465
 466         tmds_chip->tmds_chip_slave_addr = restore;
 467 }
 468
 469 /* If Disable DVI, turn off pad */
 470 void viafb_dvi_disable(void)
 471 {
 472         if (viaparinfo->chip_info->
 473                 tmds_chip_info.output_interface == INTERFACE_TMDS)
 474                 /* Turn off TMDS power. */
 475                 viafb_write_reg(CRD2, VIACR,
 476                 viafb_read_reg(VIACR, CRD2) | 0x08);
 477 }
 478
 479 static void dvi_patch_skew_dvp0(void)
 480 {
 481         /* Reset data driving first: */
 482         viafb_write_reg_mask(SR1B, VIASR, 0, BIT1);
 483         viafb_write_reg_mask(SR2A, VIASR, 0, BIT4);
 484
 485         switch (viaparinfo->chip_info->gfx_chip_name) {
 486         case UNICHROME_P4M890:
 487                 {
 488                         if ((viaparinfo->tmds_setting_info->h_active == 1600) &&
 489                                 (viaparinfo->tmds_setting_info->v_active ==
 490                                 1200))
 491                                 viafb_write_reg_mask(CR96, VIACR, 0x03,
 492                                                BIT0 + BIT1 + BIT2);
 493                         else
 494                                 viafb_write_reg_mask(CR96, VIACR, 0x07,
 495                                                BIT0 + BIT1 + BIT2);
 496                         break;
 497                 }
 498
 499         case UNICHROME_P4M900:
 500                 {
 501                         viafb_write_reg_mask(CR96, VIACR, 0x07,
 502                                        BIT0 + BIT1 + BIT2 + BIT3);
 503                         viafb_write_reg_mask(SR1B, VIASR, 0x02, BIT1);
 504                         viafb_write_reg_mask(SR2A, VIASR, 0x10, BIT4);
 505                         break;
 506                 }
 507
 508         default:
 509                 {
 510                         break;
 511                 }
 512         }
 513 }
 514
 515 static void dvi_patch_skew_dvp_low(void)
 516 {
 517         switch (viaparinfo->chip_info->gfx_chip_name) {
 518         case UNICHROME_K8M890:
 519                 {
 520                         viafb_write_reg_mask(CR99, VIACR, 0x03, BIT0 + BIT1);
 521                         break;
 522                 }
 523
 524         case UNICHROME_P4M900:
 525                 {
 526                         viafb_write_reg_mask(CR99, VIACR, 0x08,
 527                                        BIT0 + BIT1 + BIT2 + BIT3);
 528                         break;
 529                 }
 530
 531         case UNICHROME_P4M890:
 532                 {
 533                         viafb_write_reg_mask(CR99, VIACR, 0x0F,
 534                                        BIT0 + BIT1 + BIT2 + BIT3);
 535                         break;
 536                 }
 537
 538         default:
 539                 {
 540                         break;
 541                 }
 542         }
 543 }
 544
 545 /* If Enable DVI, turn off pad */
 546 void viafb_dvi_enable(void)
 547 {
 548         u8 data;
 549
 550         switch (viaparinfo->chip_info->tmds_chip_info.output_interface) {
 551         case INTERFACE_DVP0:
 552                 viafb_write_reg_mask(CR6B, VIACR, 0x01, BIT0);
 553                 viafb_write_reg_mask(CR6C, VIACR, 0x21, BIT0 + BIT5);
 554                 dvi_patch_skew_dvp0();
 555                 if (viaparinfo->chip_info->gfx_chip_name == UNICHROME_CLE266)
 556                         tmds_register_write(0x88, 0x3b);
 557                 else
 558                         /*clear CR91[5] to direct on display period
 559                            in the secondary diplay path */
 560                         via_write_reg_mask(VIACR, 0x91, 0x00, 0x20);
 561                 break;
 562
 563         case INTERFACE_DVP1:
 564                 if (viaparinfo->chip_info->gfx_chip_name == UNICHROME_CLE266)
 565                         viafb_write_reg_mask(CR93, VIACR, 0x21, BIT0 + BIT5);
 566
 567                 /*fix dvi cann't be enabled with MB VT5718C4 - Al Zhang */
 568                 if (viaparinfo->chip_info->gfx_chip_name == UNICHROME_CLE266)
 569                         tmds_register_write(0x88, 0x3b);
 570                 else
 571                         /*clear CR91[5] to direct on display period
 572                           in the secondary diplay path */
 573                         via_write_reg_mask(VIACR, 0x91, 0x00, 0x20);
 574
 575                 /*fix DVI cannot enable on EPIA-M board */
 576                 if (viafb_platform_epia_dvi == 1) {
 577                         viafb_write_reg_mask(CR91, VIACR, 0x1f, 0x1f);
 578                         viafb_write_reg_mask(CR88, VIACR, 0x00, BIT6 + BIT0);
 579                         if (viafb_bus_width == 24) {
 580                                 if (viafb_device_lcd_dualedge == 1)
 581                                         data = 0x3F;
 582                                 else
 583                                         data = 0x37;
 584                                 viafb_i2c_writebyte(viaparinfo->chip_info->
 585                                         tmds_chip_info.i2c_port,
 586                                         viaparinfo->chip_info->
 587                                         tmds_chip_info.tmds_chip_slave_addr,
 588                                         0x08, data);
 589                         }
 590                 }
 591                 break;
 592
 593         case INTERFACE_DFP_HIGH:
 594                 if (viaparinfo->chip_info->gfx_chip_name != UNICHROME_CLE266)
 595                         via_write_reg_mask(VIACR, CR97, 0x03, 0x03);
 596
 597                 via_write_reg_mask(VIACR, 0x91, 0x00, 0x20);
 598                 break;
 599
 600         case INTERFACE_DFP_LOW:
 601                 if (viaparinfo->chip_info->gfx_chip_name == UNICHROME_CLE266)
 602                         break;
 603
 604                 dvi_patch_skew_dvp_low();
 605                 via_write_reg_mask(VIACR, 0x91, 0x00, 0x20);
 606                 break;
 607
 608         case INTERFACE_TMDS:
 609                 /* Turn on Display period in the panel path. */
 610                 viafb_write_reg_mask(CR91, VIACR, 0, BIT7);
 611
 612                 /* Turn on TMDS power. */
 613                 viafb_write_reg_mask(CRD2, VIACR, 0, BIT3);
 614                 break;
 615         }
 616
 617         if (viaparinfo->tmds_setting_info->iga_path == IGA2) {
 618                 /* Disable LCD Scaling */
 619                 viafb_write_reg_mask(CR79, VIACR, 0x00, BIT0);
 620         }
 621 }