exynos_drm_dsi.c 37 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524
/*
 * Samsung SoC MIPI DSI Master driver.
 *
 * Copyright (c) 2014 Samsung Electronics Co., Ltd
 *
 * Contacts: Tomasz Figa <t.figa@samsung.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
*/

#include <drm/drmP.h>
#include <drm/drm_crtc_helper.h>
#include <drm/drm_mipi_dsi.h>
#include <drm/drm_panel.h>

#include <linux/clk.h>
#include <linux/irq.h>
#include <linux/phy/phy.h>
#include <linux/regulator/consumer.h>

#include <video/mipi_display.h>
#include <video/videomode.h>

#include "exynos_drm_drv.h"

/* returns true iff both arguments logically differs */
#define NEQV(a, b) (!(a) ^ !(b))

#define DSIM_STATUS_REG		0x0	/* Status register */
#define DSIM_SWRST_REG		0x4	/* Software reset register */
#define DSIM_CLKCTRL_REG	0x8	/* Clock control register */
#define DSIM_TIMEOUT_REG	0xc	/* Time out register */
#define DSIM_CONFIG_REG		0x10	/* Configuration register */
#define DSIM_ESCMODE_REG	0x14	/* Escape mode register */

/* Main display image resolution register */
#define DSIM_MDRESOL_REG	0x18
#define DSIM_MVPORCH_REG	0x1c	/* Main display Vporch register */
#define DSIM_MHPORCH_REG	0x20	/* Main display Hporch register */
#define DSIM_MSYNC_REG		0x24	/* Main display sync area register */

/* Sub display image resolution register */
#define DSIM_SDRESOL_REG	0x28
#define DSIM_INTSRC_REG		0x2c	/* Interrupt source register */
#define DSIM_INTMSK_REG		0x30	/* Interrupt mask register */
#define DSIM_PKTHDR_REG		0x34	/* Packet Header FIFO register */
#define DSIM_PAYLOAD_REG	0x38	/* Payload FIFO register */
#define DSIM_RXFIFO_REG		0x3c	/* Read FIFO register */
#define DSIM_FIFOTHLD_REG	0x40	/* FIFO threshold level register */
#define DSIM_FIFOCTRL_REG	0x44	/* FIFO status and control register */

/* FIFO memory AC characteristic register */
#define DSIM_PLLCTRL_REG	0x4c	/* PLL control register */
#define DSIM_PLLTMR_REG		0x50	/* PLL timer register */
#define DSIM_PHYACCHR_REG	0x54	/* D-PHY AC characteristic register */
#define DSIM_PHYACCHR1_REG	0x58	/* D-PHY AC characteristic register1 */

/* DSIM_STATUS */
#define DSIM_STOP_STATE_DAT(x)		(((x) & 0xf) << 0)
#define DSIM_STOP_STATE_CLK		(1 << 8)
#define DSIM_TX_READY_HS_CLK		(1 << 10)
#define DSIM_PLL_STABLE			(1 << 31)

/* DSIM_SWRST */
#define DSIM_FUNCRST			(1 << 16)
#define DSIM_SWRST			(1 << 0)

/* DSIM_TIMEOUT */
#define DSIM_LPDR_TIMEOUT(x)		((x) << 0)
#define DSIM_BTA_TIMEOUT(x)		((x) << 16)

/* DSIM_CLKCTRL */
#define DSIM_ESC_PRESCALER(x)		(((x) & 0xffff) << 0)
#define DSIM_ESC_PRESCALER_MASK		(0xffff << 0)
#define DSIM_LANE_ESC_CLK_EN_CLK	(1 << 19)
#define DSIM_LANE_ESC_CLK_EN_DATA(x)	(((x) & 0xf) << 20)
#define DSIM_LANE_ESC_CLK_EN_DATA_MASK	(0xf << 20)
#define DSIM_BYTE_CLKEN			(1 << 24)
#define DSIM_BYTE_CLK_SRC(x)		(((x) & 0x3) << 25)
#define DSIM_BYTE_CLK_SRC_MASK		(0x3 << 25)
#define DSIM_PLL_BYPASS			(1 << 27)
#define DSIM_ESC_CLKEN			(1 << 28)
#define DSIM_TX_REQUEST_HSCLK		(1 << 31)

/* DSIM_CONFIG */
#define DSIM_LANE_EN_CLK		(1 << 0)
#define DSIM_LANE_EN(x)			(((x) & 0xf) << 1)
#define DSIM_NUM_OF_DATA_LANE(x)	(((x) & 0x3) << 5)
#define DSIM_SUB_PIX_FORMAT(x)		(((x) & 0x7) << 8)
#define DSIM_MAIN_PIX_FORMAT_MASK	(0x7 << 12)
#define DSIM_MAIN_PIX_FORMAT_RGB888	(0x7 << 12)
#define DSIM_MAIN_PIX_FORMAT_RGB666	(0x6 << 12)
#define DSIM_MAIN_PIX_FORMAT_RGB666_P	(0x5 << 12)
#define DSIM_MAIN_PIX_FORMAT_RGB565	(0x4 << 12)
#define DSIM_SUB_VC			(((x) & 0x3) << 16)
#define DSIM_MAIN_VC			(((x) & 0x3) << 18)
#define DSIM_HSA_MODE			(1 << 20)
#define DSIM_HBP_MODE			(1 << 21)
#define DSIM_HFP_MODE			(1 << 22)
#define DSIM_HSE_MODE			(1 << 23)
#define DSIM_AUTO_MODE			(1 << 24)
#define DSIM_VIDEO_MODE			(1 << 25)
#define DSIM_BURST_MODE			(1 << 26)
#define DSIM_SYNC_INFORM		(1 << 27)
#define DSIM_EOT_DISABLE		(1 << 28)
#define DSIM_MFLUSH_VS			(1 << 29)

/* DSIM_ESCMODE */
#define DSIM_TX_TRIGGER_RST		(1 << 4)
#define DSIM_TX_LPDT_LP			(1 << 6)
#define DSIM_CMD_LPDT_LP		(1 << 7)
#define DSIM_FORCE_BTA			(1 << 16)
#define DSIM_FORCE_STOP_STATE		(1 << 20)
#define DSIM_STOP_STATE_CNT(x)		(((x) & 0x7ff) << 21)
#define DSIM_STOP_STATE_CNT_MASK	(0x7ff << 21)

/* DSIM_MDRESOL */
#define DSIM_MAIN_STAND_BY		(1 << 31)
#define DSIM_MAIN_VRESOL(x)		(((x) & 0x7ff) << 16)
#define DSIM_MAIN_HRESOL(x)		(((x) & 0X7ff) << 0)

/* DSIM_MVPORCH */
#define DSIM_CMD_ALLOW(x)		((x) << 28)
#define DSIM_STABLE_VFP(x)		((x) << 16)
#define DSIM_MAIN_VBP(x)		((x) << 0)
#define DSIM_CMD_ALLOW_MASK		(0xf << 28)
#define DSIM_STABLE_VFP_MASK		(0x7ff << 16)
#define DSIM_MAIN_VBP_MASK		(0x7ff << 0)

/* DSIM_MHPORCH */
#define DSIM_MAIN_HFP(x)		((x) << 16)
#define DSIM_MAIN_HBP(x)		((x) << 0)
#define DSIM_MAIN_HFP_MASK		((0xffff) << 16)
#define DSIM_MAIN_HBP_MASK		((0xffff) << 0)

/* DSIM_MSYNC */
#define DSIM_MAIN_VSA(x)		((x) << 22)
#define DSIM_MAIN_HSA(x)		((x) << 0)
#define DSIM_MAIN_VSA_MASK		((0x3ff) << 22)
#define DSIM_MAIN_HSA_MASK		((0xffff) << 0)

/* DSIM_SDRESOL */
#define DSIM_SUB_STANDY(x)		((x) << 31)
#define DSIM_SUB_VRESOL(x)		((x) << 16)
#define DSIM_SUB_HRESOL(x)		((x) << 0)
#define DSIM_SUB_STANDY_MASK		((0x1) << 31)
#define DSIM_SUB_VRESOL_MASK		((0x7ff) << 16)
#define DSIM_SUB_HRESOL_MASK		((0x7ff) << 0)

/* DSIM_INTSRC */
#define DSIM_INT_PLL_STABLE		(1 << 31)
#define DSIM_INT_SW_RST_RELEASE		(1 << 30)
#define DSIM_INT_SFR_FIFO_EMPTY		(1 << 29)
#define DSIM_INT_BTA			(1 << 25)
#define DSIM_INT_FRAME_DONE		(1 << 24)
#define DSIM_INT_RX_TIMEOUT		(1 << 21)
#define DSIM_INT_BTA_TIMEOUT		(1 << 20)
#define DSIM_INT_RX_DONE		(1 << 18)
#define DSIM_INT_RX_TE			(1 << 17)
#define DSIM_INT_RX_ACK			(1 << 16)
#define DSIM_INT_RX_ECC_ERR		(1 << 15)
#define DSIM_INT_RX_CRC_ERR		(1 << 14)

/* DSIM_FIFOCTRL */
#define DSIM_RX_DATA_FULL		(1 << 25)
#define DSIM_RX_DATA_EMPTY		(1 << 24)
#define DSIM_SFR_HEADER_FULL		(1 << 23)
#define DSIM_SFR_HEADER_EMPTY		(1 << 22)
#define DSIM_SFR_PAYLOAD_FULL		(1 << 21)
#define DSIM_SFR_PAYLOAD_EMPTY		(1 << 20)
#define DSIM_I80_HEADER_FULL		(1 << 19)
#define DSIM_I80_HEADER_EMPTY		(1 << 18)
#define DSIM_I80_PAYLOAD_FULL		(1 << 17)
#define DSIM_I80_PAYLOAD_EMPTY		(1 << 16)
#define DSIM_SD_HEADER_FULL		(1 << 15)
#define DSIM_SD_HEADER_EMPTY		(1 << 14)
#define DSIM_SD_PAYLOAD_FULL		(1 << 13)
#define DSIM_SD_PAYLOAD_EMPTY		(1 << 12)
#define DSIM_MD_HEADER_FULL		(1 << 11)
#define DSIM_MD_HEADER_EMPTY		(1 << 10)
#define DSIM_MD_PAYLOAD_FULL		(1 << 9)
#define DSIM_MD_PAYLOAD_EMPTY		(1 << 8)
#define DSIM_RX_FIFO			(1 << 4)
#define DSIM_SFR_FIFO			(1 << 3)
#define DSIM_I80_FIFO			(1 << 2)
#define DSIM_SD_FIFO			(1 << 1)
#define DSIM_MD_FIFO			(1 << 0)

/* DSIM_PHYACCHR */
#define DSIM_AFC_EN			(1 << 14)
#define DSIM_AFC_CTL(x)			(((x) & 0x7) << 5)

/* DSIM_PLLCTRL */
#define DSIM_FREQ_BAND(x)		((x) << 24)
#define DSIM_PLL_EN			(1 << 23)
#define DSIM_PLL_P(x)			((x) << 13)
#define DSIM_PLL_M(x)			((x) << 4)
#define DSIM_PLL_S(x)			((x) << 1)

#define DSI_MAX_BUS_WIDTH		4
#define DSI_NUM_VIRTUAL_CHANNELS	4
#define DSI_TX_FIFO_SIZE		2048
#define DSI_RX_FIFO_SIZE		256
#define DSI_XFER_TIMEOUT_MS		100
#define DSI_RX_FIFO_EMPTY		0x30800002

enum exynos_dsi_transfer_type {
	EXYNOS_DSI_TX,
	EXYNOS_DSI_RX,
};

struct exynos_dsi_transfer {
	struct list_head list;
	struct completion completed;
	int result;
	u8 data_id;
	u8 data[2];
	u16 flags;

	const u8 *tx_payload;
	u16 tx_len;
	u16 tx_done;

	u8 *rx_payload;
	u16 rx_len;
	u16 rx_done;
};

#define DSIM_STATE_ENABLED		BIT(0)
#define DSIM_STATE_INITIALIZED		BIT(1)
#define DSIM_STATE_CMD_LPM		BIT(2)

struct exynos_dsi {
	struct mipi_dsi_host dsi_host;
	struct drm_connector connector;
	struct drm_encoder *encoder;
	struct device_node *panel_node;
	struct drm_panel *panel;
	struct device *dev;

	void __iomem *reg_base;
	struct phy *phy;
	struct clk *pll_clk;
	struct clk *bus_clk;
	struct regulator_bulk_data supplies[2];
	int irq;

	u32 pll_clk_rate;
	u32 burst_clk_rate;
	u32 esc_clk_rate;
	u32 lanes;
	u32 mode_flags;
	u32 format;
	struct videomode vm;

	int state;
	struct drm_property *brightness;
	struct completion completed;

	spinlock_t transfer_lock; /* protects transfer_list */
	struct list_head transfer_list;
};

#define host_to_dsi(host) container_of(host, struct exynos_dsi, dsi_host)
#define connector_to_dsi(c) container_of(c, struct exynos_dsi, connector)

static void exynos_dsi_wait_for_reset(struct exynos_dsi *dsi)
{
	if (wait_for_completion_timeout(&dsi->completed, msecs_to_jiffies(300)))
		return;

	dev_err(dsi->dev, "timeout waiting for reset\n");
}

static void exynos_dsi_reset(struct exynos_dsi *dsi)
{
	reinit_completion(&dsi->completed);
	writel(DSIM_SWRST, dsi->reg_base + DSIM_SWRST_REG);
}

#ifndef MHZ
#define MHZ	(1000*1000)
#endif

static unsigned long exynos_dsi_pll_find_pms(struct exynos_dsi *dsi,
		unsigned long fin, unsigned long fout, u8 *p, u16 *m, u8 *s)
{
	unsigned long best_freq = 0;
	u32 min_delta = 0xffffffff;
	u8 p_min, p_max;
	u8 _p, uninitialized_var(best_p);
	u16 _m, uninitialized_var(best_m);
	u8 _s, uninitialized_var(best_s);

	p_min = DIV_ROUND_UP(fin, (12 * MHZ));
	p_max = fin / (6 * MHZ);

	for (_p = p_min; _p <= p_max; ++_p) {
		for (_s = 0; _s <= 5; ++_s) {
			u64 tmp;
			u32 delta;

			tmp = (u64)fout * (_p << _s);
			do_div(tmp, fin);
			_m = tmp;
			if (_m < 41 || _m > 125)
				continue;

			tmp = (u64)_m * fin;
			do_div(tmp, _p);
			if (tmp < 500 * MHZ || tmp > 1000 * MHZ)
				continue;

			tmp = (u64)_m * fin;
			do_div(tmp, _p << _s);

			delta = abs(fout - tmp);
			if (delta < min_delta) {
				best_p = _p;
				best_m = _m;
				best_s = _s;
				min_delta = delta;
				best_freq = tmp;
			}
		}
	}

	if (best_freq) {
		*p = best_p;
		*m = best_m;
		*s = best_s;
	}

	return best_freq;
}

static unsigned long exynos_dsi_set_pll(struct exynos_dsi *dsi,
					unsigned long freq)
{
	static const unsigned long freq_bands[] = {
		100 * MHZ, 120 * MHZ, 160 * MHZ, 200 * MHZ,
		270 * MHZ, 320 * MHZ, 390 * MHZ, 450 * MHZ,
		510 * MHZ, 560 * MHZ, 640 * MHZ, 690 * MHZ,
		770 * MHZ, 870 * MHZ, 950 * MHZ,
	};
	unsigned long fin, fout;
	int timeout, band;
	u8 p, s;
	u16 m;
	u32 reg;

	clk_set_rate(dsi->pll_clk, dsi->pll_clk_rate);

	fin = clk_get_rate(dsi->pll_clk);
	if (!fin) {
		dev_err(dsi->dev, "failed to get PLL clock frequency\n");
		return 0;
	}

	dev_dbg(dsi->dev, "PLL input frequency: %lu\n", fin);

	fout = exynos_dsi_pll_find_pms(dsi, fin, freq, &p, &m, &s);
	if (!fout) {
		dev_err(dsi->dev,
			"failed to find PLL PMS for requested frequency\n");
		return -EFAULT;
	}

	for (band = 0; band < ARRAY_SIZE(freq_bands); ++band)
		if (fout < freq_bands[band])
			break;

	dev_dbg(dsi->dev, "PLL freq %lu, (p %d, m %d, s %d), band %d\n", fout,
		p, m, s, band);

	writel(500, dsi->reg_base + DSIM_PLLTMR_REG);

	reg = DSIM_FREQ_BAND(band) | DSIM_PLL_EN
			| DSIM_PLL_P(p) | DSIM_PLL_M(m) | DSIM_PLL_S(s);
	writel(reg, dsi->reg_base + DSIM_PLLCTRL_REG);

	timeout = 1000;
	do {
		if (timeout-- == 0) {
			dev_err(dsi->dev, "PLL failed to stabilize\n");
			return -EFAULT;
		}
		reg = readl(dsi->reg_base + DSIM_STATUS_REG);
	} while ((reg & DSIM_PLL_STABLE) == 0);

	return fout;
}

static int exynos_dsi_enable_clock(struct exynos_dsi *dsi)
{
	unsigned long hs_clk, byte_clk, esc_clk;
	unsigned long esc_div;
	u32 reg;

	hs_clk = exynos_dsi_set_pll(dsi, dsi->burst_clk_rate);
	if (!hs_clk) {
		dev_err(dsi->dev, "failed to configure DSI PLL\n");
		return -EFAULT;
	}

	byte_clk = hs_clk / 8;
	esc_div = DIV_ROUND_UP(byte_clk, dsi->esc_clk_rate);
	esc_clk = byte_clk / esc_div;

	if (esc_clk > 20 * MHZ) {
		++esc_div;
		esc_clk = byte_clk / esc_div;
	}

	dev_dbg(dsi->dev, "hs_clk = %lu, byte_clk = %lu, esc_clk = %lu\n",
		hs_clk, byte_clk, esc_clk);

	reg = readl(dsi->reg_base + DSIM_CLKCTRL_REG);
	reg &= ~(DSIM_ESC_PRESCALER_MASK | DSIM_LANE_ESC_CLK_EN_CLK
			| DSIM_LANE_ESC_CLK_EN_DATA_MASK | DSIM_PLL_BYPASS
			| DSIM_BYTE_CLK_SRC_MASK);
	reg |= DSIM_ESC_CLKEN | DSIM_BYTE_CLKEN
			| DSIM_ESC_PRESCALER(esc_div)
			| DSIM_LANE_ESC_CLK_EN_CLK
			| DSIM_LANE_ESC_CLK_EN_DATA(BIT(dsi->lanes) - 1)
			| DSIM_BYTE_CLK_SRC(0)
			| DSIM_TX_REQUEST_HSCLK;
	writel(reg, dsi->reg_base + DSIM_CLKCTRL_REG);

	return 0;
}

static void exynos_dsi_disable_clock(struct exynos_dsi *dsi)
{
	u32 reg;

	reg = readl(dsi->reg_base + DSIM_CLKCTRL_REG);
	reg &= ~(DSIM_LANE_ESC_CLK_EN_CLK | DSIM_LANE_ESC_CLK_EN_DATA_MASK
			| DSIM_ESC_CLKEN | DSIM_BYTE_CLKEN);
	writel(reg, dsi->reg_base + DSIM_CLKCTRL_REG);

	reg = readl(dsi->reg_base + DSIM_PLLCTRL_REG);
	reg &= ~DSIM_PLL_EN;
	writel(reg, dsi->reg_base + DSIM_PLLCTRL_REG);
}

static int exynos_dsi_init_link(struct exynos_dsi *dsi)
{
	int timeout;
	u32 reg;
	u32 lanes_mask;

	/* Initialize FIFO pointers */
	reg = readl(dsi->reg_base + DSIM_FIFOCTRL_REG);
	reg &= ~0x1f;
	writel(reg, dsi->reg_base + DSIM_FIFOCTRL_REG);

	usleep_range(9000, 11000);

	reg |= 0x1f;
	writel(reg, dsi->reg_base + DSIM_FIFOCTRL_REG);

	usleep_range(9000, 11000);

	/* DSI configuration */
	reg = 0;

	if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO) {
		reg |= DSIM_VIDEO_MODE;

		if (!(dsi->mode_flags & MIPI_DSI_MODE_VSYNC_FLUSH))
			reg |= DSIM_MFLUSH_VS;
		if (!(dsi->mode_flags & MIPI_DSI_MODE_EOT_PACKET))
			reg |= DSIM_EOT_DISABLE;
		if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE)
			reg |= DSIM_SYNC_INFORM;
		if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_BURST)
			reg |= DSIM_BURST_MODE;
		if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_AUTO_VERT)
			reg |= DSIM_AUTO_MODE;
		if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_HSE)
			reg |= DSIM_HSE_MODE;
		if (!(dsi->mode_flags & MIPI_DSI_MODE_VIDEO_HFP))
			reg |= DSIM_HFP_MODE;
		if (!(dsi->mode_flags & MIPI_DSI_MODE_VIDEO_HBP))
			reg |= DSIM_HBP_MODE;
		if (!(dsi->mode_flags & MIPI_DSI_MODE_VIDEO_HSA))
			reg |= DSIM_HSA_MODE;
	}

	switch (dsi->format) {
	case MIPI_DSI_FMT_RGB888:
		reg |= DSIM_MAIN_PIX_FORMAT_RGB888;
		break;
	case MIPI_DSI_FMT_RGB666:
		reg |= DSIM_MAIN_PIX_FORMAT_RGB666;
		break;
	case MIPI_DSI_FMT_RGB666_PACKED:
		reg |= DSIM_MAIN_PIX_FORMAT_RGB666_P;
		break;
	case MIPI_DSI_FMT_RGB565:
		reg |= DSIM_MAIN_PIX_FORMAT_RGB565;
		break;
	default:
		dev_err(dsi->dev, "invalid pixel format\n");
		return -EINVAL;
	}

	reg |= DSIM_NUM_OF_DATA_LANE(dsi->lanes - 1);

	writel(reg, dsi->reg_base + DSIM_CONFIG_REG);

	reg |= DSIM_LANE_EN_CLK;
	writel(reg, dsi->reg_base + DSIM_CONFIG_REG);

	lanes_mask = BIT(dsi->lanes) - 1;
	reg |= DSIM_LANE_EN(lanes_mask);
	writel(reg, dsi->reg_base + DSIM_CONFIG_REG);

	/* Check clock and data lane state are stop state */
	timeout = 100;
	do {
		if (timeout-- == 0) {
			dev_err(dsi->dev, "waiting for bus lanes timed out\n");
			return -EFAULT;
		}

		reg = readl(dsi->reg_base + DSIM_STATUS_REG);
		if ((reg & DSIM_STOP_STATE_DAT(lanes_mask))
		    != DSIM_STOP_STATE_DAT(lanes_mask))
			continue;
	} while (!(reg & (DSIM_STOP_STATE_CLK | DSIM_TX_READY_HS_CLK)));

	reg = readl(dsi->reg_base + DSIM_ESCMODE_REG);
	reg &= ~DSIM_STOP_STATE_CNT_MASK;
	reg |= DSIM_STOP_STATE_CNT(0xf);
	writel(reg, dsi->reg_base + DSIM_ESCMODE_REG);

	reg = DSIM_BTA_TIMEOUT(0xff) | DSIM_LPDR_TIMEOUT(0xffff);
	writel(reg, dsi->reg_base + DSIM_TIMEOUT_REG);

	return 0;
}

static void exynos_dsi_set_display_mode(struct exynos_dsi *dsi)
{
	struct videomode *vm = &dsi->vm;
	u32 reg;

	if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO) {
		reg = DSIM_CMD_ALLOW(0xf)
			| DSIM_STABLE_VFP(vm->vfront_porch)
			| DSIM_MAIN_VBP(vm->vback_porch);
		writel(reg, dsi->reg_base + DSIM_MVPORCH_REG);

		reg = DSIM_MAIN_HFP(vm->hfront_porch)
			| DSIM_MAIN_HBP(vm->hback_porch);
		writel(reg, dsi->reg_base + DSIM_MHPORCH_REG);

		reg = DSIM_MAIN_VSA(vm->vsync_len)
			| DSIM_MAIN_HSA(vm->hsync_len);
		writel(reg, dsi->reg_base + DSIM_MSYNC_REG);
	}

	reg = DSIM_MAIN_HRESOL(vm->hactive) | DSIM_MAIN_VRESOL(vm->vactive);
	writel(reg, dsi->reg_base + DSIM_MDRESOL_REG);

	dev_dbg(dsi->dev, "LCD size = %dx%d\n", vm->hactive, vm->vactive);
}

static void exynos_dsi_set_display_enable(struct exynos_dsi *dsi, bool enable)
{
	u32 reg;

	reg = readl(dsi->reg_base + DSIM_MDRESOL_REG);
	if (enable)
		reg |= DSIM_MAIN_STAND_BY;
	else
		reg &= ~DSIM_MAIN_STAND_BY;
	writel(reg, dsi->reg_base + DSIM_MDRESOL_REG);
}

static int exynos_dsi_wait_for_hdr_fifo(struct exynos_dsi *dsi)
{
	int timeout = 2000;

	do {
		u32 reg = readl(dsi->reg_base + DSIM_FIFOCTRL_REG);

		if (!(reg & DSIM_SFR_HEADER_FULL))
			return 0;

		if (!cond_resched())
			usleep_range(950, 1050);
	} while (--timeout);

	return -ETIMEDOUT;
}

static void exynos_dsi_set_cmd_lpm(struct exynos_dsi *dsi, bool lpm)
{
	u32 v = readl(dsi->reg_base + DSIM_ESCMODE_REG);

	if (lpm)
		v |= DSIM_CMD_LPDT_LP;
	else
		v &= ~DSIM_CMD_LPDT_LP;

	writel(v, dsi->reg_base + DSIM_ESCMODE_REG);
}

static void exynos_dsi_force_bta(struct exynos_dsi *dsi)
{
	u32 v = readl(dsi->reg_base + DSIM_ESCMODE_REG);

	v |= DSIM_FORCE_BTA;
	writel(v, dsi->reg_base + DSIM_ESCMODE_REG);
}

static void exynos_dsi_send_to_fifo(struct exynos_dsi *dsi,
					struct exynos_dsi_transfer *xfer)
{
	struct device *dev = dsi->dev;
	const u8 *payload = xfer->tx_payload + xfer->tx_done;
	u16 length = xfer->tx_len - xfer->tx_done;
	bool first = !xfer->tx_done;
	u32 reg;

	dev_dbg(dev, "< xfer %p: tx len %u, done %u, rx len %u, done %u\n",
		xfer, xfer->tx_len, xfer->tx_done, xfer->rx_len, xfer->rx_done);

	if (length > DSI_TX_FIFO_SIZE)
		length = DSI_TX_FIFO_SIZE;

	xfer->tx_done += length;

	/* Send payload */
	while (length >= 4) {
		reg = (payload[3] << 24) | (payload[2] << 16)
					| (payload[1] << 8) | payload[0];
		writel(reg, dsi->reg_base + DSIM_PAYLOAD_REG);
		payload += 4;
		length -= 4;
	}

	reg = 0;
	switch (length) {
	case 3:
		reg |= payload[2] << 16;
		/* Fall through */
	case 2:
		reg |= payload[1] << 8;
		/* Fall through */
	case 1:
		reg |= payload[0];
		writel(reg, dsi->reg_base + DSIM_PAYLOAD_REG);
		break;
	case 0:
		/* Do nothing */
		break;
	}

	/* Send packet header */
	if (!first)
		return;

	reg = (xfer->data[1] << 16) | (xfer->data[0] << 8) | xfer->data_id;
	if (exynos_dsi_wait_for_hdr_fifo(dsi)) {
		dev_err(dev, "waiting for header FIFO timed out\n");
		return;
	}

	if (NEQV(xfer->flags & MIPI_DSI_MSG_USE_LPM,
		 dsi->state & DSIM_STATE_CMD_LPM)) {
		exynos_dsi_set_cmd_lpm(dsi, xfer->flags & MIPI_DSI_MSG_USE_LPM);
		dsi->state ^= DSIM_STATE_CMD_LPM;
	}

	writel(reg, dsi->reg_base + DSIM_PKTHDR_REG);

	if (xfer->flags & MIPI_DSI_MSG_REQ_ACK)
		exynos_dsi_force_bta(dsi);
}

static void exynos_dsi_read_from_fifo(struct exynos_dsi *dsi,
					struct exynos_dsi_transfer *xfer)
{
	u8 *payload = xfer->rx_payload + xfer->rx_done;
	bool first = !xfer->rx_done;
	struct device *dev = dsi->dev;
	u16 length;
	u32 reg;

	if (first) {
		reg = readl(dsi->reg_base + DSIM_RXFIFO_REG);

		switch (reg & 0x3f) {
		case MIPI_DSI_RX_GENERIC_SHORT_READ_RESPONSE_2BYTE:
		case MIPI_DSI_RX_DCS_SHORT_READ_RESPONSE_2BYTE:
			if (xfer->rx_len >= 2) {
				payload[1] = reg >> 16;
				++xfer->rx_done;
			}
			/* Fall through */
		case MIPI_DSI_RX_GENERIC_SHORT_READ_RESPONSE_1BYTE:
		case MIPI_DSI_RX_DCS_SHORT_READ_RESPONSE_1BYTE:
			payload[0] = reg >> 8;
			++xfer->rx_done;
			xfer->rx_len = xfer->rx_done;
			xfer->result = 0;
			goto clear_fifo;
		case MIPI_DSI_RX_ACKNOWLEDGE_AND_ERROR_REPORT:
			dev_err(dev, "DSI Error Report: 0x%04x\n",
				(reg >> 8) & 0xffff);
			xfer->result = 0;
			goto clear_fifo;
		}

		length = (reg >> 8) & 0xffff;
		if (length > xfer->rx_len) {
			dev_err(dev,
				"response too long (%u > %u bytes), stripping\n",
				xfer->rx_len, length);
			length = xfer->rx_len;
		} else if (length < xfer->rx_len)
			xfer->rx_len = length;
	}

	length = xfer->rx_len - xfer->rx_done;
	xfer->rx_done += length;

	/* Receive payload */
	while (length >= 4) {
		reg = readl(dsi->reg_base + DSIM_RXFIFO_REG);
		payload[0] = (reg >>  0) & 0xff;
		payload[1] = (reg >>  8) & 0xff;
		payload[2] = (reg >> 16) & 0xff;
		payload[3] = (reg >> 24) & 0xff;
		payload += 4;
		length -= 4;
	}

	if (length) {
		reg = readl(dsi->reg_base + DSIM_RXFIFO_REG);
		switch (length) {
		case 3:
			payload[2] = (reg >> 16) & 0xff;
			/* Fall through */
		case 2:
			payload[1] = (reg >> 8) & 0xff;
			/* Fall through */
		case 1:
			payload[0] = reg & 0xff;
		}
	}

	if (xfer->rx_done == xfer->rx_len)
		xfer->result = 0;

clear_fifo:
	length = DSI_RX_FIFO_SIZE / 4;
	do {
		reg = readl(dsi->reg_base + DSIM_RXFIFO_REG);
		if (reg == DSI_RX_FIFO_EMPTY)
			break;
	} while (--length);
}

static void exynos_dsi_transfer_start(struct exynos_dsi *dsi)
{
	unsigned long flags;
	struct exynos_dsi_transfer *xfer;
	bool start = false;

again:
	spin_lock_irqsave(&dsi->transfer_lock, flags);

	if (list_empty(&dsi->transfer_list)) {
		spin_unlock_irqrestore(&dsi->transfer_lock, flags);
		return;
	}

	xfer = list_first_entry(&dsi->transfer_list,
					struct exynos_dsi_transfer, list);

	spin_unlock_irqrestore(&dsi->transfer_lock, flags);

	if (xfer->tx_len && xfer->tx_done == xfer->tx_len)
		/* waiting for RX */
		return;

	exynos_dsi_send_to_fifo(dsi, xfer);

	if (xfer->tx_len || xfer->rx_len)
		return;

	xfer->result = 0;
	complete(&xfer->completed);

	spin_lock_irqsave(&dsi->transfer_lock, flags);

	list_del_init(&xfer->list);
	start = !list_empty(&dsi->transfer_list);

	spin_unlock_irqrestore(&dsi->transfer_lock, flags);

	if (start)
		goto again;
}

static bool exynos_dsi_transfer_finish(struct exynos_dsi *dsi)
{
	struct exynos_dsi_transfer *xfer;
	unsigned long flags;
	bool start = true;

	spin_lock_irqsave(&dsi->transfer_lock, flags);

	if (list_empty(&dsi->transfer_list)) {
		spin_unlock_irqrestore(&dsi->transfer_lock, flags);
		return false;
	}

	xfer = list_first_entry(&dsi->transfer_list,
					struct exynos_dsi_transfer, list);

	spin_unlock_irqrestore(&dsi->transfer_lock, flags);

	dev_dbg(dsi->dev,
		"> xfer %p, tx_len %u, tx_done %u, rx_len %u, rx_done %u\n",
		xfer, xfer->tx_len, xfer->tx_done, xfer->rx_len, xfer->rx_done);

	if (xfer->tx_done != xfer->tx_len)
		return true;

	if (xfer->rx_done != xfer->rx_len)
		exynos_dsi_read_from_fifo(dsi, xfer);

	if (xfer->rx_done != xfer->rx_len)
		return true;

	spin_lock_irqsave(&dsi->transfer_lock, flags);

	list_del_init(&xfer->list);
	start = !list_empty(&dsi->transfer_list);

	spin_unlock_irqrestore(&dsi->transfer_lock, flags);

	if (!xfer->rx_len)
		xfer->result = 0;
	complete(&xfer->completed);

	return start;
}

static void exynos_dsi_remove_transfer(struct exynos_dsi *dsi,
					struct exynos_dsi_transfer *xfer)
{
	unsigned long flags;
	bool start;

	spin_lock_irqsave(&dsi->transfer_lock, flags);

	if (!list_empty(&dsi->transfer_list) &&
	    xfer == list_first_entry(&dsi->transfer_list,
				     struct exynos_dsi_transfer, list)) {
		list_del_init(&xfer->list);
		start = !list_empty(&dsi->transfer_list);
		spin_unlock_irqrestore(&dsi->transfer_lock, flags);
		if (start)
			exynos_dsi_transfer_start(dsi);
		return;
	}

	list_del_init(&xfer->list);

	spin_unlock_irqrestore(&dsi->transfer_lock, flags);
}

static int exynos_dsi_transfer(struct exynos_dsi *dsi,
					struct exynos_dsi_transfer *xfer)
{
	unsigned long flags;
	bool stopped;

	xfer->tx_done = 0;
	xfer->rx_done = 0;
	xfer->result = -ETIMEDOUT;
	init_completion(&xfer->completed);

	spin_lock_irqsave(&dsi->transfer_lock, flags);

	stopped = list_empty(&dsi->transfer_list);
	list_add_tail(&xfer->list, &dsi->transfer_list);

	spin_unlock_irqrestore(&dsi->transfer_lock, flags);

	if (stopped)
		exynos_dsi_transfer_start(dsi);

	wait_for_completion_timeout(&xfer->completed,
				    msecs_to_jiffies(DSI_XFER_TIMEOUT_MS));
	if (xfer->result == -ETIMEDOUT) {
		exynos_dsi_remove_transfer(dsi, xfer);
		dev_err(dsi->dev, "xfer timed out: %*ph %*ph\n", 2, xfer->data,
			xfer->tx_len, xfer->tx_payload);
		return -ETIMEDOUT;
	}

	/* Also covers hardware timeout condition */
	return xfer->result;
}

static irqreturn_t exynos_dsi_irq(int irq, void *dev_id)
{
	struct exynos_dsi *dsi = dev_id;
	u32 status;

	status = readl(dsi->reg_base + DSIM_INTSRC_REG);
	if (!status) {
		static unsigned long int j;
		if (printk_timed_ratelimit(&j, 500))
			dev_warn(dsi->dev, "spurious interrupt\n");
		return IRQ_HANDLED;
	}
	writel(status, dsi->reg_base + DSIM_INTSRC_REG);

	if (status & DSIM_INT_SW_RST_RELEASE) {
		u32 mask = ~(DSIM_INT_RX_DONE | DSIM_INT_SFR_FIFO_EMPTY);
		writel(mask, dsi->reg_base + DSIM_INTMSK_REG);
		complete(&dsi->completed);
		return IRQ_HANDLED;
	}

	if (!(status & (DSIM_INT_RX_DONE | DSIM_INT_SFR_FIFO_EMPTY)))
		return IRQ_HANDLED;

	if (exynos_dsi_transfer_finish(dsi))
		exynos_dsi_transfer_start(dsi);

	return IRQ_HANDLED;
}

static int exynos_dsi_init(struct exynos_dsi *dsi)
{
	exynos_dsi_enable_clock(dsi);
	exynos_dsi_reset(dsi);
	enable_irq(dsi->irq);
	exynos_dsi_wait_for_reset(dsi);
	exynos_dsi_init_link(dsi);

	return 0;
}

static int exynos_dsi_host_attach(struct mipi_dsi_host *host,
				  struct mipi_dsi_device *device)
{
	struct exynos_dsi *dsi = host_to_dsi(host);

	dsi->lanes = device->lanes;
	dsi->format = device->format;
	dsi->mode_flags = device->mode_flags;
	dsi->panel_node = device->dev.of_node;

	if (dsi->connector.dev)
		drm_helper_hpd_irq_event(dsi->connector.dev);

	return 0;
}

static int exynos_dsi_host_detach(struct mipi_dsi_host *host,
				  struct mipi_dsi_device *device)
{
	struct exynos_dsi *dsi = host_to_dsi(host);

	dsi->panel_node = NULL;

	if (dsi->connector.dev)
		drm_helper_hpd_irq_event(dsi->connector.dev);

	return 0;
}

/* distinguish between short and long DSI packet types */
static bool exynos_dsi_is_short_dsi_type(u8 type)
{
	return (type & 0x0f) <= 8;
}

static ssize_t exynos_dsi_host_transfer(struct mipi_dsi_host *host,
				       struct mipi_dsi_msg *msg)
{
	struct exynos_dsi *dsi = host_to_dsi(host);
	struct exynos_dsi_transfer xfer;
	int ret;

	if (!(dsi->state & DSIM_STATE_INITIALIZED)) {
		ret = exynos_dsi_init(dsi);
		if (ret)
			return ret;
		dsi->state |= DSIM_STATE_INITIALIZED;
	}

	if (msg->tx_len == 0)
		return -EINVAL;

	xfer.data_id = msg->type | (msg->channel << 6);

	if (exynos_dsi_is_short_dsi_type(msg->type)) {
		const char *tx_buf = msg->tx_buf;

		if (msg->tx_len > 2)
			return -EINVAL;
		xfer.tx_len = 0;
		xfer.data[0] = tx_buf[0];
		xfer.data[1] = (msg->tx_len == 2) ? tx_buf[1] : 0;
	} else {
		xfer.tx_len = msg->tx_len;
		xfer.data[0] = msg->tx_len & 0xff;
		xfer.data[1] = msg->tx_len >> 8;
		xfer.tx_payload = msg->tx_buf;
	}

	xfer.rx_len = msg->rx_len;
	xfer.rx_payload = msg->rx_buf;
	xfer.flags = msg->flags;

	ret = exynos_dsi_transfer(dsi, &xfer);
	return (ret < 0) ? ret : xfer.rx_done;
}

static const struct mipi_dsi_host_ops exynos_dsi_ops = {
	.attach = exynos_dsi_host_attach,
	.detach = exynos_dsi_host_detach,
	.transfer = exynos_dsi_host_transfer,
};

static int exynos_dsi_poweron(struct exynos_dsi *dsi)
{
	int ret;

	ret = regulator_bulk_enable(ARRAY_SIZE(dsi->supplies), dsi->supplies);
	if (ret < 0) {
		dev_err(dsi->dev, "cannot enable regulators %d\n", ret);
		return ret;
	}

	ret = clk_prepare_enable(dsi->bus_clk);
	if (ret < 0) {
		dev_err(dsi->dev, "cannot enable bus clock %d\n", ret);
		goto err_bus_clk;
	}

	ret = clk_prepare_enable(dsi->pll_clk);
	if (ret < 0) {
		dev_err(dsi->dev, "cannot enable pll clock %d\n", ret);
		goto err_pll_clk;
	}

	ret = phy_power_on(dsi->phy);
	if (ret < 0) {
		dev_err(dsi->dev, "cannot enable phy %d\n", ret);
		goto err_phy;
	}

	return 0;

err_phy:
	clk_disable_unprepare(dsi->pll_clk);
err_pll_clk:
	clk_disable_unprepare(dsi->bus_clk);
err_bus_clk:
	regulator_bulk_disable(ARRAY_SIZE(dsi->supplies), dsi->supplies);

	return ret;
}

static void exynos_dsi_poweroff(struct exynos_dsi *dsi)
{
	int ret;

	usleep_range(10000, 20000);

	if (dsi->state & DSIM_STATE_INITIALIZED) {
		dsi->state &= ~DSIM_STATE_INITIALIZED;

		exynos_dsi_disable_clock(dsi);

		disable_irq(dsi->irq);
	}

	dsi->state &= ~DSIM_STATE_CMD_LPM;

	phy_power_off(dsi->phy);

	clk_disable_unprepare(dsi->pll_clk);
	clk_disable_unprepare(dsi->bus_clk);

	ret = regulator_bulk_disable(ARRAY_SIZE(dsi->supplies), dsi->supplies);
	if (ret < 0)
		dev_err(dsi->dev, "cannot disable regulators %d\n", ret);
}

static int exynos_dsi_enable(struct exynos_dsi *dsi)
{
	int ret;

	if (dsi->state & DSIM_STATE_ENABLED)
		return 0;

	ret = exynos_dsi_poweron(dsi);
	if (ret < 0)
		return ret;

	ret = drm_panel_enable(dsi->panel);
	if (ret < 0) {
		exynos_dsi_poweroff(dsi);
		return ret;
	}

	exynos_dsi_set_display_mode(dsi);
	exynos_dsi_set_display_enable(dsi, true);

	dsi->state |= DSIM_STATE_ENABLED;

	return 0;
}

static void exynos_dsi_disable(struct exynos_dsi *dsi)
{
	if (!(dsi->state & DSIM_STATE_ENABLED))
		return;

	exynos_dsi_set_display_enable(dsi, false);
	drm_panel_disable(dsi->panel);
	exynos_dsi_poweroff(dsi);

	dsi->state &= ~DSIM_STATE_ENABLED;
}

static void exynos_dsi_dpms(struct exynos_drm_display *display, int mode)
{
	struct exynos_dsi *dsi = display->ctx;

	if (dsi->panel) {
		switch (mode) {
		case DRM_MODE_DPMS_ON:
			exynos_dsi_enable(dsi);
			break;
		case DRM_MODE_DPMS_STANDBY:
		case DRM_MODE_DPMS_SUSPEND:
		case DRM_MODE_DPMS_OFF:
			exynos_dsi_disable(dsi);
			break;
		default:
			break;
		}
	}
}

static enum drm_connector_status
exynos_dsi_detect(struct drm_connector *connector, bool force)
{
	struct exynos_dsi *dsi = connector_to_dsi(connector);

	if (!dsi->panel) {
		dsi->panel = of_drm_find_panel(dsi->panel_node);
		if (dsi->panel)
			drm_panel_attach(dsi->panel, &dsi->connector);
	} else if (!dsi->panel_node) {
		struct exynos_drm_display *display;

		display = platform_get_drvdata(to_platform_device(dsi->dev));
		exynos_dsi_dpms(display, DRM_MODE_DPMS_OFF);
		drm_panel_detach(dsi->panel);
		dsi->panel = NULL;
	}

	if (dsi->panel)
		return connector_status_connected;

	return connector_status_disconnected;
}

static void exynos_dsi_connector_destroy(struct drm_connector *connector)
{
}

static struct drm_connector_funcs exynos_dsi_connector_funcs = {
	.dpms = drm_helper_connector_dpms,
	.detect = exynos_dsi_detect,
	.fill_modes = drm_helper_probe_single_connector_modes,
	.destroy = exynos_dsi_connector_destroy,
};

static int exynos_dsi_get_modes(struct drm_connector *connector)
{
	struct exynos_dsi *dsi = connector_to_dsi(connector);

	if (dsi->panel)
		return dsi->panel->funcs->get_modes(dsi->panel);

	return 0;
}

static int exynos_dsi_mode_valid(struct drm_connector *connector,
				 struct drm_display_mode *mode)
{
	return MODE_OK;
}

static struct drm_encoder *
exynos_dsi_best_encoder(struct drm_connector *connector)
{
	struct exynos_dsi *dsi = connector_to_dsi(connector);

	return dsi->encoder;
}

static struct drm_connector_helper_funcs exynos_dsi_connector_helper_funcs = {
	.get_modes = exynos_dsi_get_modes,
	.mode_valid = exynos_dsi_mode_valid,
	.best_encoder = exynos_dsi_best_encoder,
};

static int exynos_dsi_create_connector(struct exynos_drm_display *display,
				       struct drm_encoder *encoder)
{
	struct exynos_dsi *dsi = display->ctx;
	struct drm_connector *connector = &dsi->connector;
	int ret;

	dsi->encoder = encoder;

	connector->polled = DRM_CONNECTOR_POLL_HPD;

	ret = drm_connector_init(encoder->dev, connector,
				 &exynos_dsi_connector_funcs,
				 DRM_MODE_CONNECTOR_DSI);
	if (ret) {
		DRM_ERROR("Failed to initialize connector with drm\n");
		return ret;
	}

	drm_connector_helper_add(connector, &exynos_dsi_connector_helper_funcs);
	drm_sysfs_connector_add(connector);
	drm_mode_connector_attach_encoder(connector, encoder);

	return 0;
}

static void exynos_dsi_mode_set(struct exynos_drm_display *display,
			 struct drm_display_mode *mode)
{
	struct exynos_dsi *dsi = display->ctx;
	struct videomode *vm = &dsi->vm;

	vm->hactive = mode->hdisplay;
	vm->vactive = mode->vdisplay;
	vm->vfront_porch = mode->vsync_start - mode->vdisplay;
	vm->vback_porch = mode->vtotal - mode->vsync_end;
	vm->vsync_len = mode->vsync_end - mode->vsync_start;
	vm->hfront_porch = mode->hsync_start - mode->hdisplay;
	vm->hback_porch = mode->htotal - mode->hsync_end;
	vm->hsync_len = mode->hsync_end - mode->hsync_start;
}

static struct exynos_drm_display_ops exynos_dsi_display_ops = {
	.create_connector = exynos_dsi_create_connector,
	.mode_set = exynos_dsi_mode_set,
	.dpms = exynos_dsi_dpms
};

static struct exynos_drm_display exynos_dsi_display = {
	.type = EXYNOS_DISPLAY_TYPE_LCD,
	.ops = &exynos_dsi_display_ops,
};

/* of_* functions will be removed after merge of of_graph patches */
static struct device_node *
of_get_child_by_name_reg(struct device_node *parent, const char *name, u32 reg)
{
	struct device_node *np;

	for_each_child_of_node(parent, np) {
		u32 r;

		if (!np->name || of_node_cmp(np->name, name))
			continue;

		if (of_property_read_u32(np, "reg", &r) < 0)
			r = 0;

		if (reg == r)
			break;
	}

	return np;
}

static struct device_node *of_graph_get_port_by_reg(struct device_node *parent,
						    u32 reg)
{
	struct device_node *ports, *port;

	ports = of_get_child_by_name(parent, "ports");
	if (ports)
		parent = ports;

	port = of_get_child_by_name_reg(parent, "port", reg);

	of_node_put(ports);

	return port;
}

static struct device_node *
of_graph_get_endpoint_by_reg(struct device_node *port, u32 reg)
{
	return of_get_child_by_name_reg(port, "endpoint", reg);
}

static int exynos_dsi_of_read_u32(const struct device_node *np,
				  const char *propname, u32 *out_value)
{
	int ret = of_property_read_u32(np, propname, out_value);

	if (ret < 0)
		pr_err("%s: failed to get '%s' property\n", np->full_name,
		       propname);

	return ret;
}

enum {
	DSI_PORT_IN,
	DSI_PORT_OUT
};

static int exynos_dsi_parse_dt(struct exynos_dsi *dsi)
{
	struct device *dev = dsi->dev;
	struct device_node *node = dev->of_node;
	struct device_node *port, *ep;
	int ret;

	ret = exynos_dsi_of_read_u32(node, "samsung,pll-clock-frequency",
				     &dsi->pll_clk_rate);
	if (ret < 0)
		return ret;

	port = of_graph_get_port_by_reg(node, DSI_PORT_OUT);
	if (!port) {
		dev_err(dev, "no output port specified\n");
		return -EINVAL;
	}

	ep = of_graph_get_endpoint_by_reg(port, 0);
	of_node_put(port);
	if (!ep) {
		dev_err(dev, "no endpoint specified in output port\n");
		return -EINVAL;
	}

	ret = exynos_dsi_of_read_u32(ep, "samsung,burst-clock-frequency",
				     &dsi->burst_clk_rate);
	if (ret < 0)
		goto end;

	ret = exynos_dsi_of_read_u32(ep, "samsung,esc-clock-frequency",
				     &dsi->esc_clk_rate);

end:
	of_node_put(ep);

	return ret;
}

static int exynos_dsi_probe(struct platform_device *pdev)
{
	struct resource *res;
	struct exynos_dsi *dsi;
	int ret;

	dsi = devm_kzalloc(&pdev->dev, sizeof(*dsi), GFP_KERNEL);
	if (!dsi) {
		dev_err(&pdev->dev, "failed to allocate dsi object.\n");
		return -ENOMEM;
	}

	init_completion(&dsi->completed);
	spin_lock_init(&dsi->transfer_lock);
	INIT_LIST_HEAD(&dsi->transfer_list);

	dsi->dsi_host.ops = &exynos_dsi_ops;
	dsi->dsi_host.dev = &pdev->dev;

	dsi->dev = &pdev->dev;

	ret = exynos_dsi_parse_dt(dsi);
	if (ret)
		return ret;

	dsi->supplies[0].supply = "vddcore";
	dsi->supplies[1].supply = "vddio";
	ret = devm_regulator_bulk_get(&pdev->dev, ARRAY_SIZE(dsi->supplies),
				      dsi->supplies);
	if (ret) {
		dev_info(&pdev->dev, "failed to get regulators: %d\n", ret);
		return -EPROBE_DEFER;
	}

	dsi->pll_clk = devm_clk_get(&pdev->dev, "pll_clk");
	if (IS_ERR(dsi->pll_clk)) {
		dev_info(&pdev->dev, "failed to get dsi pll input clock\n");
		return -EPROBE_DEFER;
	}

	dsi->bus_clk = devm_clk_get(&pdev->dev, "bus_clk");
	if (IS_ERR(dsi->bus_clk)) {
		dev_info(&pdev->dev, "failed to get dsi bus clock\n");
		return -EPROBE_DEFER;
	}

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	dsi->reg_base = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(dsi->reg_base)) {
		dev_err(&pdev->dev, "failed to remap io region\n");
		return PTR_ERR(dsi->reg_base);
	}

	dsi->phy = devm_phy_get(&pdev->dev, "dsim");
	if (IS_ERR(dsi->phy)) {
		dev_info(&pdev->dev, "failed to get dsim phy\n");
		return -EPROBE_DEFER;
	}

	dsi->irq = platform_get_irq(pdev, 0);
	if (dsi->irq < 0) {
		dev_err(&pdev->dev, "failed to request dsi irq resource\n");
		return dsi->irq;
	}

	irq_set_status_flags(dsi->irq, IRQ_NOAUTOEN);
	ret = devm_request_threaded_irq(&pdev->dev, dsi->irq, NULL,
					exynos_dsi_irq, IRQF_ONESHOT,
					dev_name(&pdev->dev), dsi);
	if (ret) {
		dev_err(&pdev->dev, "failed to request dsi irq\n");
		return ret;
	}

	exynos_dsi_display.ctx = dsi;

	platform_set_drvdata(pdev, &exynos_dsi_display);
	exynos_drm_display_register(&exynos_dsi_display);

	return mipi_dsi_host_register(&dsi->dsi_host);
}

static int exynos_dsi_remove(struct platform_device *pdev)
{
	struct exynos_dsi *dsi = exynos_dsi_display.ctx;

	exynos_dsi_dpms(&exynos_dsi_display, DRM_MODE_DPMS_OFF);

	exynos_drm_display_unregister(&exynos_dsi_display);
	mipi_dsi_host_unregister(&dsi->dsi_host);

	return 0;
}

#if CONFIG_PM_SLEEP
static int exynos_dsi_resume(struct device *dev)
{
	struct exynos_dsi *dsi = exynos_dsi_display.ctx;

	if (dsi->state & DSIM_STATE_ENABLED) {
		dsi->state &= ~DSIM_STATE_ENABLED;
		exynos_dsi_enable(dsi);
	}

	return 0;
}

static int exynos_dsi_suspend(struct device *dev)
{
	struct exynos_dsi *dsi = exynos_dsi_display.ctx;

	if (dsi->state & DSIM_STATE_ENABLED) {
		exynos_dsi_disable(dsi);
		dsi->state |= DSIM_STATE_ENABLED;
	}

	return 0;
}
#endif

static const struct dev_pm_ops exynos_dsi_pm_ops = {
	SET_SYSTEM_SLEEP_PM_OPS(exynos_dsi_suspend, exynos_dsi_resume)
};

static struct of_device_id exynos_dsi_of_match[] = {
	{ .compatible = "samsung,exynos4210-mipi-dsi" },
	{ }
};

struct platform_driver dsi_driver = {
	.probe = exynos_dsi_probe,
	.remove = exynos_dsi_remove,
	.driver = {
		   .name = "exynos-dsi",
		   .owner = THIS_MODULE,
		   .pm = &exynos_dsi_pm_ops,
		   .of_match_table = exynos_dsi_of_match,
	},
};

MODULE_AUTHOR("Tomasz Figa <t.figa@samsung.com>");
MODULE_AUTHOR("Andrzej Hajda <a.hajda@samsung.com>");
MODULE_DESCRIPTION("Samsung SoC MIPI DSI Master");
MODULE_LICENSE("GPL v2");