drivers/gpu/drm/rcar-du/rcar_lvds.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * rcar_lvds.c  --  R-Car LVDS Encoder
   4  *
   5  * Copyright (C) 2013-2018 Renesas Electronics Corporation
   6  *
   7  * Contact: Laurent Pinchart ([email protected])
   8  */
   9
  10 #include <linux/clk.h>
  11 #include <linux/delay.h>
  12 #include <linux/io.h>
  13 #include <linux/module.h>
  14 #include <linux/of.h>
  15 #include <linux/of_device.h>
  16 #include <linux/of_graph.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/slab.h>
  19 #include <linux/sys_soc.h>
  20
  21 #include <drm/drm_atomic.h>
  22 #include <drm/drm_atomic_helper.h>
  23 #include <drm/drm_bridge.h>
  24 #include <drm/drm_of.h>
  25 #include <drm/drm_panel.h>
  26 #include <drm/drm_print.h>
  27 #include <drm/drm_probe_helper.h>
  28
  29 #include "rcar_lvds.h"
  30 #include "rcar_lvds_regs.h"
  31
  32 struct rcar_lvds;
  33
  34 /* Keep in sync with the LVDCR0.LVMD hardware register values. */
  35 enum rcar_lvds_mode {
  36         RCAR_LVDS_MODE_JEIDA = 0,
  37         RCAR_LVDS_MODE_MIRROR = 1,
  38         RCAR_LVDS_MODE_VESA = 4,
  39 };
  40
  41 enum rcar_lvds_link_type {
  42         RCAR_LVDS_SINGLE_LINK = 0,
  43         RCAR_LVDS_DUAL_LINK_EVEN_ODD_PIXELS = 1,
  44         RCAR_LVDS_DUAL_LINK_ODD_EVEN_PIXELS = 2,
  45 };
  46
  47 #define RCAR_LVDS_QUIRK_LANES           BIT(0)  /* LVDS lanes 1 and 3 inverted */
  48 #define RCAR_LVDS_QUIRK_GEN3_LVEN       BIT(1)  /* LVEN bit needs to be set on R8A77970/R8A7799x */
  49 #define RCAR_LVDS_QUIRK_PWD             BIT(2)  /* PWD bit available (all of Gen3 but E3) */
  50 #define RCAR_LVDS_QUIRK_EXT_PLL         BIT(3)  /* Has extended PLL */
  51 #define RCAR_LVDS_QUIRK_DUAL_LINK       BIT(4)  /* Supports dual-link operation */
  52
  53 struct rcar_lvds_device_info {
  54         unsigned int gen;
  55         unsigned int quirks;
  56         void (*pll_setup)(struct rcar_lvds *lvds, unsigned int freq);
  57 };
  58
  59 struct rcar_lvds {
  60         struct device *dev;
  61         const struct rcar_lvds_device_info *info;
  62
  63         struct drm_bridge bridge;
  64
  65         struct drm_bridge *next_bridge;
  66         struct drm_panel *panel;
  67
  68         void __iomem *mmio;
  69         struct {
  70                 struct clk *mod;                /* CPG module clock */
  71                 struct clk *extal;              /* External clock */
  72                 struct clk *dotclkin[2];        /* External DU clocks */
  73         } clocks;
  74
  75         struct drm_bridge *companion;
  76         enum rcar_lvds_link_type link_type;
  77 };
  78
  79 #define bridge_to_rcar_lvds(b) \
  80         container_of(b, struct rcar_lvds, bridge)
  81
  82 static void rcar_lvds_write(struct rcar_lvds *lvds, u32 reg, u32 data)
  83 {
  84         iowrite32(data, lvds->mmio + reg);
  85 }
  86
  87 /* -----------------------------------------------------------------------------
  88  * PLL Setup
  89  */
  90
  91 static void rcar_lvds_pll_setup_gen2(struct rcar_lvds *lvds, unsigned int freq)
  92 {
  93         u32 val;
  94
  95         if (freq < 39000000)
  96                 val = LVDPLLCR_CEEN | LVDPLLCR_COSEL | LVDPLLCR_PLLDLYCNT_38M;
  97         else if (freq < 61000000)
  98                 val = LVDPLLCR_CEEN | LVDPLLCR_COSEL | LVDPLLCR_PLLDLYCNT_60M;
  99         else if (freq < 121000000)
 100                 val = LVDPLLCR_CEEN | LVDPLLCR_COSEL | LVDPLLCR_PLLDLYCNT_121M;
 101         else
 102                 val = LVDPLLCR_PLLDLYCNT_150M;
 103
 104         rcar_lvds_write(lvds, LVDPLLCR, val);
 105 }
 106
 107 static void rcar_lvds_pll_setup_gen3(struct rcar_lvds *lvds, unsigned int freq)
 108 {
 109         u32 val;
 110
 111         if (freq < 42000000)
 112                 val = LVDPLLCR_PLLDIVCNT_42M;
 113         else if (freq < 85000000)
 114                 val = LVDPLLCR_PLLDIVCNT_85M;
 115         else if (freq < 128000000)
 116                 val = LVDPLLCR_PLLDIVCNT_128M;
 117         else
 118                 val = LVDPLLCR_PLLDIVCNT_148M;
 119
 120         rcar_lvds_write(lvds, LVDPLLCR, val);
 121 }
 122
 123 struct pll_info {
 124         unsigned long diff;
 125         unsigned int pll_m;
 126         unsigned int pll_n;
 127         unsigned int pll_e;
 128         unsigned int div;
 129         u32 clksel;
 130 };
 131
 132 static void rcar_lvds_d3_e3_pll_calc(struct rcar_lvds *lvds, struct clk *clk,
 133                                      unsigned long target, struct pll_info *pll,
 134                                      u32 clksel, bool dot_clock_only)
 135 {
 136         unsigned int div7 = dot_clock_only ? 1 : 7;
 137         unsigned long output;
 138         unsigned long fin;
 139         unsigned int m_min;
 140         unsigned int m_max;
 141         unsigned int m;
 142         int error;
 143
 144         if (!clk)
 145                 return;
 146
 147         /*
 148          * The LVDS PLL is made of a pre-divider and a multiplier (strangely
 149          * enough called M and N respectively), followed by a post-divider E.
 150          *
 151          *         ,-----.         ,-----.     ,-----.         ,-----.
 152          * Fin --> | 1/M | -Fpdf-> | PFD | --> | VCO | -Fvco-> | 1/E | --> Fout
 153          *         `-----'     ,-> |     |     `-----'   |     `-----'
 154          *                     |   `-----'               |
 155          *                     |         ,-----.         |
 156          *                     `-------- | 1/N | <-------'
 157          *                               `-----'
 158          *
 159          * The clock output by the PLL is then further divided by a programmable
 160          * divider DIV to achieve the desired target frequency. Finally, an
 161          * optional fixed /7 divider is used to convert the bit clock to a pixel
 162          * clock (as LVDS transmits 7 bits per lane per clock sample).
 163          *
 164          *          ,-------.     ,-----.     |\
 165          * Fout --> | 1/DIV | --> | 1/7 | --> | |
 166          *          `-------'  |  `-----'     | | --> dot clock
 167          *                     `------------> | |
 168          *                                    |/
 169          *
 170          * The /7 divider is optional, it is enabled when the LVDS PLL is used
 171          * to drive the LVDS encoder, and disabled when  used to generate a dot
 172          * clock for the DU RGB output, without using the LVDS encoder.
 173          *
 174          * The PLL allowed input frequency range is 12 MHz to 192 MHz.
 175          */
 176
 177         fin = clk_get_rate(clk);
 178         if (fin < 12000000 || fin > 192000000)
 179                 return;
 180
 181         /*
 182          * The comparison frequency range is 12 MHz to 24 MHz, which limits the
 183          * allowed values for the pre-divider M (normal range 1-8).
 184          *
 185          * Fpfd = Fin / M
 186          */
 187         m_min = max_t(unsigned int, 1, DIV_ROUND_UP(fin, 24000000));
 188         m_max = min_t(unsigned int, 8, fin / 12000000);
 189
 190         for (m = m_min; m <= m_max; ++m) {
 191                 unsigned long fpfd;
 192                 unsigned int n_min;
 193                 unsigned int n_max;
 194                 unsigned int n;
 195
 196                 /*
 197                  * The VCO operating range is 900 Mhz to 1800 MHz, which limits
 198                  * the allowed values for the multiplier N (normal range
 199                  * 60-120).
 200                  *
 201                  * Fvco = Fin * N / M
 202                  */
 203                 fpfd = fin / m;
 204                 n_min = max_t(unsigned int, 60, DIV_ROUND_UP(900000000, fpfd));
 205                 n_max = min_t(unsigned int, 120, 1800000000 / fpfd);
 206
 207                 for (n = n_min; n < n_max; ++n) {
 208                         unsigned long fvco;
 209                         unsigned int e_min;
 210                         unsigned int e;
 211
 212                         /*
 213                          * The output frequency is limited to 1039.5 MHz,
 214                          * limiting again the allowed values for the
 215                          * post-divider E (normal value 1, 2 or 4).
 216                          *
 217                          * Fout = Fvco / E
 218                          */
 219                         fvco = fpfd * n;
 220                         e_min = fvco > 1039500000 ? 1 : 0;
 221
 222                         for (e = e_min; e < 3; ++e) {
 223                                 unsigned long fout;
 224                                 unsigned long diff;
 225                                 unsigned int div;
 226
 227                                 /*
 228                                  * Finally we have a programable divider after
 229                                  * the PLL, followed by a an optional fixed /7
 230                                  * divider.
 231                                  */
 232                                 fout = fvco / (1 << e) / div7;
 233                                 div = max(1UL, DIV_ROUND_CLOSEST(fout, target));
 234                                 diff = abs(fout / div - target);
 235
 236                                 if (diff < pll->diff) {
 237                                         pll->diff = diff;
 238                                         pll->pll_m = m;
 239                                         pll->pll_n = n;
 240                                         pll->pll_e = e;
 241                                         pll->div = div;
 242                                         pll->clksel = clksel;
 243
 244                                         if (diff == 0)
 245                                                 goto done;
 246                                 }
 247                         }
 248                 }
 249         }
 250
 251 done:
 252         output = fin * pll->pll_n / pll->pll_m / (1 << pll->pll_e)
 253                / div7 / pll->div;
 254         error = (long)(output - target) * 10000 / (long)target;
 255
 256         dev_dbg(lvds->dev,
 257                 "%pC %lu Hz -> Fout %lu Hz (target %lu Hz, error %d.%02u%%), PLL M/N/E/DIV %u/%u/%u/%u\n",
 258                 clk, fin, output, target, error / 100,
 259                 error < 0 ? -error % 100 : error % 100,
 260                 pll->pll_m, pll->pll_n, pll->pll_e, pll->div);
 261 }
 262
 263 static void __rcar_lvds_pll_setup_d3_e3(struct rcar_lvds *lvds,
 264                                         unsigned int freq, bool dot_clock_only)
 265 {
 266         struct pll_info pll = { .diff = (unsigned long)-1 };
 267         u32 lvdpllcr;
 268
 269         rcar_lvds_d3_e3_pll_calc(lvds, lvds->clocks.dotclkin[0], freq, &pll,
 270                                  LVDPLLCR_CKSEL_DU_DOTCLKIN(0), dot_clock_only);
 271         rcar_lvds_d3_e3_pll_calc(lvds, lvds->clocks.dotclkin[1], freq, &pll,
 272                                  LVDPLLCR_CKSEL_DU_DOTCLKIN(1), dot_clock_only);
 273         rcar_lvds_d3_e3_pll_calc(lvds, lvds->clocks.extal, freq, &pll,
 274                                  LVDPLLCR_CKSEL_EXTAL, dot_clock_only);
 275
 276         lvdpllcr = LVDPLLCR_PLLON | pll.clksel | LVDPLLCR_CLKOUT
 277                  | LVDPLLCR_PLLN(pll.pll_n - 1) | LVDPLLCR_PLLM(pll.pll_m - 1);
 278
 279         if (pll.pll_e > 0)
 280                 lvdpllcr |= LVDPLLCR_STP_CLKOUTE | LVDPLLCR_OUTCLKSEL
 281                          |  LVDPLLCR_PLLE(pll.pll_e - 1);
 282
 283         if (dot_clock_only)
 284                 lvdpllcr |= LVDPLLCR_OCKSEL;
 285
 286         rcar_lvds_write(lvds, LVDPLLCR, lvdpllcr);
 287
 288         if (pll.div > 1)
 289                 /*
 290                  * The DIVRESET bit is a misnomer, setting it to 1 deasserts the
 291                  * divisor reset.
 292                  */
 293                 rcar_lvds_write(lvds, LVDDIV, LVDDIV_DIVSEL |
 294                                 LVDDIV_DIVRESET | LVDDIV_DIV(pll.div - 1));
 295         else
 296                 rcar_lvds_write(lvds, LVDDIV, 0);
 297 }
 298
 299 static void rcar_lvds_pll_setup_d3_e3(struct rcar_lvds *lvds, unsigned int freq)
 300 {
 301         __rcar_lvds_pll_setup_d3_e3(lvds, freq, false);
 302 }
 303
 304 /* -----------------------------------------------------------------------------
 305  * Clock - D3/E3 only
 306  */
 307
 308 int rcar_lvds_clk_enable(struct drm_bridge *bridge, unsigned long freq)
 309 {
 310         struct rcar_lvds *lvds = bridge_to_rcar_lvds(bridge);
 311         int ret;
 312
 313         if (WARN_ON(!(lvds->info->quirks & RCAR_LVDS_QUIRK_EXT_PLL)))
 314                 return -ENODEV;
 315
 316         dev_dbg(lvds->dev, "enabling LVDS PLL, freq=%luHz\n", freq);
 317
 318         ret = clk_prepare_enable(lvds->clocks.mod);
 319         if (ret < 0)
 320                 return ret;
 321
 322         __rcar_lvds_pll_setup_d3_e3(lvds, freq, true);
 323
 324         return 0;
 325 }
 326 EXPORT_SYMBOL_GPL(rcar_lvds_clk_enable);
 327
 328 void rcar_lvds_clk_disable(struct drm_bridge *bridge)
 329 {
 330         struct rcar_lvds *lvds = bridge_to_rcar_lvds(bridge);
 331
 332         if (WARN_ON(!(lvds->info->quirks & RCAR_LVDS_QUIRK_EXT_PLL)))
 333                 return;
 334
 335         dev_dbg(lvds->dev, "disabling LVDS PLL\n");
 336
 337         rcar_lvds_write(lvds, LVDPLLCR, 0);
 338
 339         clk_disable_unprepare(lvds->clocks.mod);
 340 }
 341 EXPORT_SYMBOL_GPL(rcar_lvds_clk_disable);
 342
 343 /* -----------------------------------------------------------------------------
 344  * Bridge
 345  */
 346
 347 static enum rcar_lvds_mode rcar_lvds_get_lvds_mode(struct rcar_lvds *lvds,
 348                                         const struct drm_connector *connector)
 349 {
 350         const struct drm_display_info *info;
 351         enum rcar_lvds_mode mode;
 352
 353         /*
 354          * There is no API yet to retrieve LVDS mode from a bridge, only panels
 355          * are supported.
 356          */
 357         if (!lvds->panel)
 358                 return RCAR_LVDS_MODE_JEIDA;
 359
 360         info = &connector->display_info;
 361         if (!info->num_bus_formats || !info->bus_formats) {
 362                 dev_warn(lvds->dev,
 363                          "no LVDS bus format reported, using JEIDA\n");
 364                 return RCAR_LVDS_MODE_JEIDA;
 365         }
 366
 367         switch (info->bus_formats[0]) {
 368         case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
 369         case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
 370                 mode = RCAR_LVDS_MODE_JEIDA;
 371                 break;
 372         case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
 373                 mode = RCAR_LVDS_MODE_VESA;
 374                 break;
 375         default:
 376                 dev_warn(lvds->dev,
 377                          "unsupported LVDS bus format 0x%04x, using JEIDA\n",
 378                          info->bus_formats[0]);
 379                 return RCAR_LVDS_MODE_JEIDA;
 380         }
 381
 382         if (info->bus_flags & DRM_BUS_FLAG_DATA_LSB_TO_MSB)
 383                 mode |= RCAR_LVDS_MODE_MIRROR;
 384
 385         return mode;
 386 }
 387
 388 static void __rcar_lvds_atomic_enable(struct drm_bridge *bridge,
 389                                       struct drm_atomic_state *state,
 390                                       struct drm_crtc *crtc,
 391                                       struct drm_connector *connector)
 392 {
 393         struct rcar_lvds *lvds = bridge_to_rcar_lvds(bridge);
 394         u32 lvdhcr;
 395         u32 lvdcr0;
 396         int ret;
 397
 398         ret = clk_prepare_enable(lvds->clocks.mod);
 399         if (ret < 0)
 400                 return;
 401
 402         /* Enable the companion LVDS encoder in dual-link mode. */
 403         if (lvds->link_type != RCAR_LVDS_SINGLE_LINK && lvds->companion)
 404                 __rcar_lvds_atomic_enable(lvds->companion, state, crtc,
 405                                           connector);
 406
 407         /*
 408          * Hardcode the channels and control signals routing for now.
 409          *
 410          * HSYNC -> CTRL0
 411          * VSYNC -> CTRL1
 412          * DISP  -> CTRL2
 413          * 0     -> CTRL3
 414          */
 415         rcar_lvds_write(lvds, LVDCTRCR, LVDCTRCR_CTR3SEL_ZERO |
 416                         LVDCTRCR_CTR2SEL_DISP | LVDCTRCR_CTR1SEL_VSYNC |
 417                         LVDCTRCR_CTR0SEL_HSYNC);
 418
 419         if (lvds->info->quirks & RCAR_LVDS_QUIRK_LANES)
 420                 lvdhcr = LVDCHCR_CHSEL_CH(0, 0) | LVDCHCR_CHSEL_CH(1, 3)
 421                        | LVDCHCR_CHSEL_CH(2, 2) | LVDCHCR_CHSEL_CH(3, 1);
 422         else
 423                 lvdhcr = LVDCHCR_CHSEL_CH(0, 0) | LVDCHCR_CHSEL_CH(1, 1)
 424                        | LVDCHCR_CHSEL_CH(2, 2) | LVDCHCR_CHSEL_CH(3, 3);
 425
 426         rcar_lvds_write(lvds, LVDCHCR, lvdhcr);
 427
 428         if (lvds->info->quirks & RCAR_LVDS_QUIRK_DUAL_LINK) {
 429                 u32 lvdstripe = 0;
 430
 431                 if (lvds->link_type != RCAR_LVDS_SINGLE_LINK) {
 432                         /*
 433                          * By default we generate even pixels from the primary
 434                          * encoder and odd pixels from the companion encoder.
 435                          * Swap pixels around if the sink requires odd pixels
 436                          * from the primary encoder and even pixels from the
 437                          * companion encoder.
 438                          */
 439                         bool swap_pixels = lvds->link_type ==
 440                                 RCAR_LVDS_DUAL_LINK_ODD_EVEN_PIXELS;
 441
 442                         /*
 443                          * Configure vertical stripe since we are dealing with
 444                          * an LVDS dual-link connection.
 445                          *
 446                          * ST_SWAP is reserved for the companion encoder, only
 447                          * set it in the primary encoder.
 448                          */
 449                         lvdstripe = LVDSTRIPE_ST_ON
 450                                   | (lvds->companion && swap_pixels ?
 451                                      LVDSTRIPE_ST_SWAP : 0);
 452                 }
 453                 rcar_lvds_write(lvds, LVDSTRIPE, lvdstripe);
 454         }
 455
 456         /*
 457          * PLL clock configuration on all instances but the companion in
 458          * dual-link mode.
 459          */
 460         if (lvds->link_type == RCAR_LVDS_SINGLE_LINK || lvds->companion) {
 461                 const struct drm_crtc_state *crtc_state =
 462                         drm_atomic_get_new_crtc_state(state, crtc);
 463                 const struct drm_display_mode *mode =
 464                         &crtc_state->adjusted_mode;
 465
 466                 lvds->info->pll_setup(lvds, mode->clock * 1000);
 467         }
 468
 469         /* Set the LVDS mode and select the input. */
 470         lvdcr0 = rcar_lvds_get_lvds_mode(lvds, connector) << LVDCR0_LVMD_SHIFT;
 471
 472         if (lvds->bridge.encoder) {
 473                 if (drm_crtc_index(crtc) == 2)
 474                         lvdcr0 |= LVDCR0_DUSEL;
 475         }
 476
 477         rcar_lvds_write(lvds, LVDCR0, lvdcr0);
 478
 479         /* Turn all the channels on. */
 480         rcar_lvds_write(lvds, LVDCR1,
 481                         LVDCR1_CHSTBY(3) | LVDCR1_CHSTBY(2) |
 482                         LVDCR1_CHSTBY(1) | LVDCR1_CHSTBY(0) | LVDCR1_CLKSTBY);
 483
 484         if (lvds->info->gen < 3) {
 485                 /* Enable LVDS operation and turn the bias circuitry on. */
 486                 lvdcr0 |= LVDCR0_BEN | LVDCR0_LVEN;
 487                 rcar_lvds_write(lvds, LVDCR0, lvdcr0);
 488         }
 489
 490         if (!(lvds->info->quirks & RCAR_LVDS_QUIRK_EXT_PLL)) {
 491                 /*
 492                  * Turn the PLL on (simple PLL only, extended PLL is fully
 493                  * controlled through LVDPLLCR).
 494                  */
 495                 lvdcr0 |= LVDCR0_PLLON;
 496                 rcar_lvds_write(lvds, LVDCR0, lvdcr0);
 497         }
 498
 499         if (lvds->info->quirks & RCAR_LVDS_QUIRK_PWD) {
 500                 /* Set LVDS normal mode. */
 501                 lvdcr0 |= LVDCR0_PWD;
 502                 rcar_lvds_write(lvds, LVDCR0, lvdcr0);
 503         }
 504
 505         if (lvds->info->quirks & RCAR_LVDS_QUIRK_GEN3_LVEN) {
 506                 /*
 507                  * Turn on the LVDS PHY. On D3, the LVEN and LVRES bit must be
 508                  * set at the same time, so don't write the register yet.
 509                  */
 510                 lvdcr0 |= LVDCR0_LVEN;
 511                 if (!(lvds->info->quirks & RCAR_LVDS_QUIRK_PWD))
 512                         rcar_lvds_write(lvds, LVDCR0, lvdcr0);
 513         }
 514
 515         if (!(lvds->info->quirks & RCAR_LVDS_QUIRK_EXT_PLL)) {
 516                 /* Wait for the PLL startup delay (simple PLL only). */
 517                 usleep_range(100, 150);
 518         }
 519
 520         /* Turn the output on. */
 521         lvdcr0 |= LVDCR0_LVRES;
 522         rcar_lvds_write(lvds, LVDCR0, lvdcr0);
 523 }
 524
 525 static void rcar_lvds_atomic_enable(struct drm_bridge *bridge,
 526                                     struct drm_bridge_state *old_bridge_state)
 527 {
 528         struct drm_atomic_state *state = old_bridge_state->base.state;
 529         struct drm_connector *connector;
 530         struct drm_crtc *crtc;
 531
 532         connector = drm_atomic_get_new_connector_for_encoder(state,
 533                                                              bridge->encoder);
 534         crtc = drm_atomic_get_new_connector_state(state, connector)->crtc;
 535
 536         __rcar_lvds_atomic_enable(bridge, state, crtc, connector);
 537 }
 538
 539 static void rcar_lvds_atomic_disable(struct drm_bridge *bridge,
 540                                      struct drm_bridge_state *old_bridge_state)
 541 {
 542         struct rcar_lvds *lvds = bridge_to_rcar_lvds(bridge);
 543
 544         rcar_lvds_write(lvds, LVDCR0, 0);
 545         rcar_lvds_write(lvds, LVDCR1, 0);
 546         rcar_lvds_write(lvds, LVDPLLCR, 0);
 547
 548         /* Disable the companion LVDS encoder in dual-link mode. */
 549         if (lvds->link_type != RCAR_LVDS_SINGLE_LINK && lvds->companion)
 550                 lvds->companion->funcs->atomic_disable(lvds->companion,
 551                                                        old_bridge_state);
 552
 553         clk_disable_unprepare(lvds->clocks.mod);
 554 }
 555
 556 static bool rcar_lvds_mode_fixup(struct drm_bridge *bridge,
 557                                  const struct drm_display_mode *mode,
 558                                  struct drm_display_mode *adjusted_mode)
 559 {
 560         struct rcar_lvds *lvds = bridge_to_rcar_lvds(bridge);
 561         int min_freq;
 562
 563         /*
 564          * The internal LVDS encoder has a restricted clock frequency operating
 565          * range, from 5MHz to 148.5MHz on D3 and E3, and from 31MHz to
 566          * 148.5MHz on all other platforms. Clamp the clock accordingly.
 567          */
 568         min_freq = lvds->info->quirks & RCAR_LVDS_QUIRK_EXT_PLL ? 5000 : 31000;
 569         adjusted_mode->clock = clamp(adjusted_mode->clock, min_freq, 148500);
 570
 571         return true;
 572 }
 573
 574 static int rcar_lvds_attach(struct drm_bridge *bridge,
 575                             enum drm_bridge_attach_flags flags)
 576 {
 577         struct rcar_lvds *lvds = bridge_to_rcar_lvds(bridge);
 578
 579         return drm_bridge_attach(bridge->encoder, lvds->next_bridge, bridge,
 580                                  flags);
 581 }
 582
 583 static const struct drm_bridge_funcs rcar_lvds_bridge_ops = {
 584         .attach = rcar_lvds_attach,
 585         .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
 586         .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
 587         .atomic_reset = drm_atomic_helper_bridge_reset,
 588         .atomic_enable = rcar_lvds_atomic_enable,
 589         .atomic_disable = rcar_lvds_atomic_disable,
 590         .mode_fixup = rcar_lvds_mode_fixup,
 591 };
 592
 593 bool rcar_lvds_dual_link(struct drm_bridge *bridge)
 594 {
 595         struct rcar_lvds *lvds = bridge_to_rcar_lvds(bridge);
 596
 597         return lvds->link_type != RCAR_LVDS_SINGLE_LINK;
 598 }
 599 EXPORT_SYMBOL_GPL(rcar_lvds_dual_link);
 600
 601 /* -----------------------------------------------------------------------------
 602  * Probe & Remove
 603  */
 604
 605 static int rcar_lvds_parse_dt_companion(struct rcar_lvds *lvds)
 606 {
 607         const struct of_device_id *match;
 608         struct device_node *companion;
 609         struct device_node *port0, *port1;
 610         struct rcar_lvds *companion_lvds;
 611         struct device *dev = lvds->dev;
 612         int dual_link;
 613         int ret = 0;
 614
 615         /* Locate the companion LVDS encoder for dual-link operation, if any. */
 616         companion = of_parse_phandle(dev->of_node, "renesas,companion", 0);
 617         if (!companion)
 618                 return 0;
 619
 620         /*
 621          * Sanity check: the companion encoder must have the same compatible
 622          * string.
 623          */
 624         match = of_match_device(dev->driver->of_match_table, dev);
 625         if (!of_device_is_compatible(companion, match->compatible)) {
 626                 dev_err(dev, "Companion LVDS encoder is invalid\n");
 627                 ret = -ENXIO;
 628                 goto done;
 629         }
 630
 631         /*
 632          * We need to work out if the sink is expecting us to function in
 633          * dual-link mode. We do this by looking at the DT port nodes we are
 634          * connected to, if they are marked as expecting even pixels and
 635          * odd pixels than we need to enable vertical stripe output.
 636          */
 637         port0 = of_graph_get_port_by_id(dev->of_node, 1);
 638         port1 = of_graph_get_port_by_id(companion, 1);
 639         dual_link = drm_of_lvds_get_dual_link_pixel_order(port0, port1);
 640         of_node_put(port0);
 641         of_node_put(port1);
 642
 643         switch (dual_link) {
 644         case DRM_LVDS_DUAL_LINK_ODD_EVEN_PIXELS:
 645                 lvds->link_type = RCAR_LVDS_DUAL_LINK_ODD_EVEN_PIXELS;
 646                 break;
 647         case DRM_LVDS_DUAL_LINK_EVEN_ODD_PIXELS:
 648                 lvds->link_type = RCAR_LVDS_DUAL_LINK_EVEN_ODD_PIXELS;
 649                 break;
 650         default:
 651                 /*
 652                  * Early dual-link bridge specific implementations populate the
 653                  * timings field of drm_bridge. If the flag is set, we assume
 654                  * that we are expected to generate even pixels from the primary
 655                  * encoder, and odd pixels from the companion encoder.
 656                  */
 657                 if (lvds->next_bridge->timings &&
 658                     lvds->next_bridge->timings->dual_link)
 659                         lvds->link_type = RCAR_LVDS_DUAL_LINK_EVEN_ODD_PIXELS;
 660                 else
 661                         lvds->link_type = RCAR_LVDS_SINGLE_LINK;
 662         }
 663
 664         if (lvds->link_type == RCAR_LVDS_SINGLE_LINK) {
 665                 dev_dbg(dev, "Single-link configuration detected\n");
 666                 goto done;
 667         }
 668
 669         lvds->companion = of_drm_find_bridge(companion);
 670         if (!lvds->companion) {
 671                 ret = -EPROBE_DEFER;
 672                 goto done;
 673         }
 674
 675         dev_dbg(dev,
 676                 "Dual-link configuration detected (companion encoder %pOF)\n",
 677                 companion);
 678
 679         if (lvds->link_type == RCAR_LVDS_DUAL_LINK_ODD_EVEN_PIXELS)
 680                 dev_dbg(dev, "Data swapping required\n");
 681
 682         /*
 683          * FIXME: We should not be messing with the companion encoder private
 684          * data from the primary encoder, we should rather let the companion
 685          * encoder work things out on its own. However, the companion encoder
 686          * doesn't hold a reference to the primary encoder, and
 687          * drm_of_lvds_get_dual_link_pixel_order needs to be given references
 688          * to the output ports of both encoders, therefore leave it like this
 689          * for the time being.
 690          */
 691         companion_lvds = bridge_to_rcar_lvds(lvds->companion);
 692         companion_lvds->link_type = lvds->link_type;
 693
 694 done:
 695         of_node_put(companion);
 696
 697         return ret;
 698 }
 699
 700 static int rcar_lvds_parse_dt(struct rcar_lvds *lvds)
 701 {
 702         int ret;
 703
 704         ret = drm_of_find_panel_or_bridge(lvds->dev->of_node, 1, 0,
 705                                           &lvds->panel, &lvds->next_bridge);
 706         if (ret)
 707                 goto done;
 708
 709         if (lvds->panel) {
 710                 lvds->next_bridge = devm_drm_panel_bridge_add(lvds->dev,
 711                                                               lvds->panel);
 712                 if (IS_ERR_OR_NULL(lvds->next_bridge)) {
 713                         ret = -EINVAL;
 714                         goto done;
 715                 }
 716         }
 717
 718         if (lvds->info->quirks & RCAR_LVDS_QUIRK_DUAL_LINK)
 719                 ret = rcar_lvds_parse_dt_companion(lvds);
 720
 721 done:
 722         /*
 723          * On D3/E3 the LVDS encoder provides a clock to the DU, which can be
 724          * used for the DPAD output even when the LVDS output is not connected.
 725          * Don't fail probe in that case as the DU will need the bridge to
 726          * control the clock.
 727          */
 728         if (lvds->info->quirks & RCAR_LVDS_QUIRK_EXT_PLL)
 729                 return ret == -ENODEV ? 0 : ret;
 730
 731         return ret;
 732 }
 733
 734 static struct clk *rcar_lvds_get_clock(struct rcar_lvds *lvds, const char *name,
 735                                        bool optional)
 736 {
 737         struct clk *clk;
 738
 739         clk = devm_clk_get(lvds->dev, name);
 740         if (!IS_ERR(clk))
 741                 return clk;
 742
 743         if (PTR_ERR(clk) == -ENOENT && optional)
 744                 return NULL;
 745
 746         dev_err_probe(lvds->dev, PTR_ERR(clk), "failed to get %s clock\n",
 747                       name ? name : "module");
 748
 749         return clk;
 750 }
 751
 752 static int rcar_lvds_get_clocks(struct rcar_lvds *lvds)
 753 {
 754         lvds->clocks.mod = rcar_lvds_get_clock(lvds, NULL, false);
 755         if (IS_ERR(lvds->clocks.mod))
 756                 return PTR_ERR(lvds->clocks.mod);
 757
 758         /*
 759          * LVDS encoders without an extended PLL have no external clock inputs.
 760          */
 761         if (!(lvds->info->quirks & RCAR_LVDS_QUIRK_EXT_PLL))
 762                 return 0;
 763
 764         lvds->clocks.extal = rcar_lvds_get_clock(lvds, "extal", true);
 765         if (IS_ERR(lvds->clocks.extal))
 766                 return PTR_ERR(lvds->clocks.extal);
 767
 768         lvds->clocks.dotclkin[0] = rcar_lvds_get_clock(lvds, "dclkin.0", true);
 769         if (IS_ERR(lvds->clocks.dotclkin[0]))
 770                 return PTR_ERR(lvds->clocks.dotclkin[0]);
 771
 772         lvds->clocks.dotclkin[1] = rcar_lvds_get_clock(lvds, "dclkin.1", true);
 773         if (IS_ERR(lvds->clocks.dotclkin[1]))
 774                 return PTR_ERR(lvds->clocks.dotclkin[1]);
 775
 776         /* At least one input to the PLL must be available. */
 777         if (!lvds->clocks.extal && !lvds->clocks.dotclkin[0] &&
 778             !lvds->clocks.dotclkin[1]) {
 779                 dev_err(lvds->dev,
 780                         "no input clock (extal, dclkin.0 or dclkin.1)\n");
 781                 return -EINVAL;
 782         }
 783
 784         return 0;
 785 }
 786
 787 static const struct rcar_lvds_device_info rcar_lvds_r8a7790es1_info = {
 788         .gen = 2,
 789         .quirks = RCAR_LVDS_QUIRK_LANES,
 790         .pll_setup = rcar_lvds_pll_setup_gen2,
 791 };
 792
 793 static const struct soc_device_attribute lvds_quirk_matches[] = {
 794         {
 795                 .soc_id = "r8a7790", .revision = "ES1.*",
 796                 .data = &rcar_lvds_r8a7790es1_info,
 797         },
 798         { /* sentinel */ }
 799 };
 800
 801 static int rcar_lvds_probe(struct platform_device *pdev)
 802 {
 803         const struct soc_device_attribute *attr;
 804         struct rcar_lvds *lvds;
 805         struct resource *mem;
 806         int ret;
 807
 808         lvds = devm_kzalloc(&pdev->dev, sizeof(*lvds), GFP_KERNEL);
 809         if (lvds == NULL)
 810                 return -ENOMEM;
 811
 812         platform_set_drvdata(pdev, lvds);
 813
 814         lvds->dev = &pdev->dev;
 815         lvds->info = of_device_get_match_data(&pdev->dev);
 816
 817         attr = soc_device_match(lvds_quirk_matches);
 818         if (attr)
 819                 lvds->info = attr->data;
 820
 821         ret = rcar_lvds_parse_dt(lvds);
 822         if (ret < 0)
 823                 return ret;
 824
 825         lvds->bridge.funcs = &rcar_lvds_bridge_ops;
 826         lvds->bridge.of_node = pdev->dev.of_node;
 827
 828         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 829         lvds->mmio = devm_ioremap_resource(&pdev->dev, mem);
 830         if (IS_ERR(lvds->mmio))
 831                 return PTR_ERR(lvds->mmio);
 832
 833         ret = rcar_lvds_get_clocks(lvds);
 834         if (ret < 0)
 835                 return ret;
 836
 837         drm_bridge_add(&lvds->bridge);
 838
 839         return 0;
 840 }
 841
 842 static int rcar_lvds_remove(struct platform_device *pdev)
 843 {
 844         struct rcar_lvds *lvds = platform_get_drvdata(pdev);
 845
 846         drm_bridge_remove(&lvds->bridge);
 847
 848         return 0;
 849 }
 850
 851 static const struct rcar_lvds_device_info rcar_lvds_gen2_info = {
 852         .gen = 2,
 853         .pll_setup = rcar_lvds_pll_setup_gen2,
 854 };
 855
 856 static const struct rcar_lvds_device_info rcar_lvds_gen3_info = {
 857         .gen = 3,
 858         .quirks = RCAR_LVDS_QUIRK_PWD,
 859         .pll_setup = rcar_lvds_pll_setup_gen3,
 860 };
 861
 862 static const struct rcar_lvds_device_info rcar_lvds_r8a77970_info = {
 863         .gen = 3,
 864         .quirks = RCAR_LVDS_QUIRK_PWD | RCAR_LVDS_QUIRK_GEN3_LVEN,
 865         .pll_setup = rcar_lvds_pll_setup_gen2,
 866 };
 867
 868 static const struct rcar_lvds_device_info rcar_lvds_r8a77990_info = {
 869         .gen = 3,
 870         .quirks = RCAR_LVDS_QUIRK_GEN3_LVEN | RCAR_LVDS_QUIRK_EXT_PLL
 871                 | RCAR_LVDS_QUIRK_DUAL_LINK,
 872         .pll_setup = rcar_lvds_pll_setup_d3_e3,
 873 };
 874
 875 static const struct rcar_lvds_device_info rcar_lvds_r8a77995_info = {
 876         .gen = 3,
 877         .quirks = RCAR_LVDS_QUIRK_GEN3_LVEN | RCAR_LVDS_QUIRK_PWD
 878                 | RCAR_LVDS_QUIRK_EXT_PLL | RCAR_LVDS_QUIRK_DUAL_LINK,
 879         .pll_setup = rcar_lvds_pll_setup_d3_e3,
 880 };
 881
 882 static const struct of_device_id rcar_lvds_of_table[] = {
 883         { .compatible = "renesas,r8a7742-lvds", .data = &rcar_lvds_gen2_info },
 884         { .compatible = "renesas,r8a7743-lvds", .data = &rcar_lvds_gen2_info },
 885         { .compatible = "renesas,r8a7744-lvds", .data = &rcar_lvds_gen2_info },
 886         { .compatible = "renesas,r8a774a1-lvds", .data = &rcar_lvds_gen3_info },
 887         { .compatible = "renesas,r8a774b1-lvds", .data = &rcar_lvds_gen3_info },
 888         { .compatible = "renesas,r8a774c0-lvds", .data = &rcar_lvds_r8a77990_info },
 889         { .compatible = "renesas,r8a774e1-lvds", .data = &rcar_lvds_gen3_info },
 890         { .compatible = "renesas,r8a7790-lvds", .data = &rcar_lvds_gen2_info },
 891         { .compatible = "renesas,r8a7791-lvds", .data = &rcar_lvds_gen2_info },
 892         { .compatible = "renesas,r8a7793-lvds", .data = &rcar_lvds_gen2_info },
 893         { .compatible = "renesas,r8a7795-lvds", .data = &rcar_lvds_gen3_info },
 894         { .compatible = "renesas,r8a7796-lvds", .data = &rcar_lvds_gen3_info },
 895         { .compatible = "renesas,r8a77965-lvds", .data = &rcar_lvds_gen3_info },
 896         { .compatible = "renesas,r8a77970-lvds", .data = &rcar_lvds_r8a77970_info },
 897         { .compatible = "renesas,r8a77980-lvds", .data = &rcar_lvds_gen3_info },
 898         { .compatible = "renesas,r8a77990-lvds", .data = &rcar_lvds_r8a77990_info },
 899         { .compatible = "renesas,r8a77995-lvds", .data = &rcar_lvds_r8a77995_info },
 900         { }
 901 };
 902
 903 MODULE_DEVICE_TABLE(of, rcar_lvds_of_table);
 904
 905 static struct platform_driver rcar_lvds_platform_driver = {
 906         .probe          = rcar_lvds_probe,
 907         .remove         = rcar_lvds_remove,
 908         .driver         = {
 909                 .name   = "rcar-lvds",
 910                 .of_match_table = rcar_lvds_of_table,
 911         },
 912 };
 913
 914 module_platform_driver(rcar_lvds_platform_driver);
 915
 916 MODULE_AUTHOR("Laurent Pinchart <[email protected]>");
 917 MODULE_DESCRIPTION("Renesas R-Car LVDS Encoder Driver");
 918 MODULE_LICENSE("GPL");