drivers/gpu/drm/sun4i/sun4i_tcon.c

   1 /*
   2  * Copyright (C) 2015 Free Electrons
   3  * Copyright (C) 2015 NextThing Co
   4  *
   5  * Maxime Ripard <maxime.ripard@free-electrons.com>
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License as
   9  * published by the Free Software Foundation; either version 2 of
  10  * the License, or (at your option) any later version.
  11  */
  12
  13 #include <drm/drmP.h>
  14 #include <drm/drm_atomic_helper.h>
  15 #include <drm/drm_crtc.h>
  16 #include <drm/drm_crtc_helper.h>
  17 #include <drm/drm_modes.h>
  18 #include <drm/drm_panel.h>
  19
  20 #include <linux/component.h>
  21 #include <linux/ioport.h>
  22 #include <linux/of_address.h>
  23 #include <linux/of_device.h>
  24 #include <linux/of_graph.h>
  25 #include <linux/of_irq.h>
  26 #include <linux/regmap.h>
  27 #include <linux/reset.h>
  28
  29 #include "sun4i_crtc.h"
  30 #include "sun4i_dotclock.h"
  31 #include "sun4i_drv.h"
  32 #include "sun4i_rgb.h"
  33 #include "sun4i_tcon.h"
  34
  35 void sun4i_tcon_disable(struct sun4i_tcon *tcon)
  36 {
  37         DRM_DEBUG_DRIVER("Disabling TCON\n");
  38
  39         /* Disable the TCON */
  40         regmap_update_bits(tcon->regs, SUN4I_TCON_GCTL_REG,
  41                            SUN4I_TCON_GCTL_TCON_ENABLE, 0);
  42 }
  43 EXPORT_SYMBOL(sun4i_tcon_disable);
  44
  45 void sun4i_tcon_enable(struct sun4i_tcon *tcon)
  46 {
  47         DRM_DEBUG_DRIVER("Enabling TCON\n");
  48
  49         /* Enable the TCON */
  50         regmap_update_bits(tcon->regs, SUN4I_TCON_GCTL_REG,
  51                            SUN4I_TCON_GCTL_TCON_ENABLE,
  52                            SUN4I_TCON_GCTL_TCON_ENABLE);
  53 }
  54 EXPORT_SYMBOL(sun4i_tcon_enable);
  55
  56 void sun4i_tcon_channel_disable(struct sun4i_tcon *tcon, int channel)
  57 {
  58         /* Disable the TCON's channel */
  59         if (channel == 0) {
  60                 regmap_update_bits(tcon->regs, SUN4I_TCON0_CTL_REG,
  61                                    SUN4I_TCON0_CTL_TCON_ENABLE, 0);
  62                 clk_disable_unprepare(tcon->dclk);
  63                 return;
  64         }
  65
  66         WARN_ON(!tcon->quirks->has_channel_1);
  67         regmap_update_bits(tcon->regs, SUN4I_TCON1_CTL_REG,
  68                            SUN4I_TCON1_CTL_TCON_ENABLE, 0);
  69         clk_disable_unprepare(tcon->sclk1);
  70 }
  71 EXPORT_SYMBOL(sun4i_tcon_channel_disable);
  72
  73 void sun4i_tcon_channel_enable(struct sun4i_tcon *tcon, int channel)
  74 {
  75         /* Enable the TCON's channel */
  76         if (channel == 0) {
  77                 regmap_update_bits(tcon->regs, SUN4I_TCON0_CTL_REG,
  78                                    SUN4I_TCON0_CTL_TCON_ENABLE,
  79                                    SUN4I_TCON0_CTL_TCON_ENABLE);
  80                 clk_prepare_enable(tcon->dclk);
  81                 return;
  82         }
  83
  84         WARN_ON(!tcon->quirks->has_channel_1);
  85         regmap_update_bits(tcon->regs, SUN4I_TCON1_CTL_REG,
  86                            SUN4I_TCON1_CTL_TCON_ENABLE,
  87                            SUN4I_TCON1_CTL_TCON_ENABLE);
  88         clk_prepare_enable(tcon->sclk1);
  89 }
  90 EXPORT_SYMBOL(sun4i_tcon_channel_enable);
  91
  92 void sun4i_tcon_enable_vblank(struct sun4i_tcon *tcon, bool enable)
  93 {
  94         u32 mask, val = 0;
  95
  96         DRM_DEBUG_DRIVER("%sabling VBLANK interrupt\n", enable ? "En" : "Dis");
  97
  98         mask = SUN4I_TCON_GINT0_VBLANK_ENABLE(0) |
  99                SUN4I_TCON_GINT0_VBLANK_ENABLE(1);
 100
 101         if (enable)
 102                 val = mask;
 103
 104         regmap_update_bits(tcon->regs, SUN4I_TCON_GINT0_REG, mask, val);
 105 }
 106 EXPORT_SYMBOL(sun4i_tcon_enable_vblank);
 107
 108 static int sun4i_tcon_get_clk_delay(struct drm_display_mode *mode,
 109                                     int channel)
 110 {
 111         int delay = mode->vtotal - mode->vdisplay;
 112
 113         if (mode->flags & DRM_MODE_FLAG_INTERLACE)
 114                 delay /= 2;
 115
 116         if (channel == 1)
 117                 delay -= 2;
 118
 119         delay = min(delay, 30);
 120
 121         DRM_DEBUG_DRIVER("TCON %d clock delay %u\n", channel, delay);
 122
 123         return delay;
 124 }
 125
 126 void sun4i_tcon0_mode_set(struct sun4i_tcon *tcon,
 127                           struct drm_display_mode *mode)
 128 {
 129         unsigned int bp, hsync, vsync;
 130         u8 clk_delay;
 131         u32 val = 0;
 132
 133         /* Adjust clock delay */
 134         clk_delay = sun4i_tcon_get_clk_delay(mode, 0);
 135         regmap_update_bits(tcon->regs, SUN4I_TCON0_CTL_REG,
 136                            SUN4I_TCON0_CTL_CLK_DELAY_MASK,
 137                            SUN4I_TCON0_CTL_CLK_DELAY(clk_delay));
 138
 139         /* Set the resolution */
 140         regmap_write(tcon->regs, SUN4I_TCON0_BASIC0_REG,
 141                      SUN4I_TCON0_BASIC0_X(mode->crtc_hdisplay) |
 142                      SUN4I_TCON0_BASIC0_Y(mode->crtc_vdisplay));
 143
 144         /*
 145          * This is called a backporch in the register documentation,
 146          * but it really is the front porch + hsync
 147          */
 148         bp = mode->crtc_htotal - mode->crtc_hsync_start;
 149         DRM_DEBUG_DRIVER("Setting horizontal total %d, backporch %d\n",
 150                          mode->crtc_htotal, bp);
 151
 152         /* Set horizontal display timings */
 153         regmap_write(tcon->regs, SUN4I_TCON0_BASIC1_REG,
 154                      SUN4I_TCON0_BASIC1_H_TOTAL(mode->crtc_htotal) |
 155                      SUN4I_TCON0_BASIC1_H_BACKPORCH(bp));
 156
 157         /*
 158          * This is called a backporch in the register documentation,
 159          * but it really is the front porch + hsync
 160          */
 161         bp = mode->crtc_vtotal - mode->crtc_vsync_start;
 162         DRM_DEBUG_DRIVER("Setting vertical total %d, backporch %d\n",
 163                          mode->crtc_vtotal, bp);
 164
 165         /* Set vertical display timings */
 166         regmap_write(tcon->regs, SUN4I_TCON0_BASIC2_REG,
 167                      SUN4I_TCON0_BASIC2_V_TOTAL(mode->crtc_vtotal) |
 168                      SUN4I_TCON0_BASIC2_V_BACKPORCH(bp));
 169
 170         /* Set Hsync and Vsync length */
 171         hsync = mode->crtc_hsync_end - mode->crtc_hsync_start;
 172         vsync = mode->crtc_vsync_end - mode->crtc_vsync_start;
 173         DRM_DEBUG_DRIVER("Setting HSYNC %d, VSYNC %d\n", hsync, vsync);
 174         regmap_write(tcon->regs, SUN4I_TCON0_BASIC3_REG,
 175                      SUN4I_TCON0_BASIC3_V_SYNC(vsync) |
 176                      SUN4I_TCON0_BASIC3_H_SYNC(hsync));
 177
 178         /* Setup the polarity of the various signals */
 179         if (!(mode->flags & DRM_MODE_FLAG_PHSYNC))
 180                 val |= SUN4I_TCON0_IO_POL_HSYNC_POSITIVE;
 181
 182         if (!(mode->flags & DRM_MODE_FLAG_PVSYNC))
 183                 val |= SUN4I_TCON0_IO_POL_VSYNC_POSITIVE;
 184
 185         regmap_update_bits(tcon->regs, SUN4I_TCON0_IO_POL_REG,
 186                            SUN4I_TCON0_IO_POL_HSYNC_POSITIVE | SUN4I_TCON0_IO_POL_VSYNC_POSITIVE,
 187                            val);
 188
 189         /* Map output pins to channel 0 */
 190         regmap_update_bits(tcon->regs, SUN4I_TCON_GCTL_REG,
 191                            SUN4I_TCON_GCTL_IOMAP_MASK,
 192                            SUN4I_TCON_GCTL_IOMAP_TCON0);
 193
 194         /* Enable the output on the pins */
 195         regmap_write(tcon->regs, SUN4I_TCON0_IO_TRI_REG, 0);
 196 }
 197 EXPORT_SYMBOL(sun4i_tcon0_mode_set);
 198
 199 void sun4i_tcon1_mode_set(struct sun4i_tcon *tcon,
 200                           struct drm_display_mode *mode)
 201 {
 202         unsigned int bp, hsync, vsync;
 203         u8 clk_delay;
 204         u32 val;
 205
 206         WARN_ON(!tcon->quirks->has_channel_1);
 207
 208         /* Adjust clock delay */
 209         clk_delay = sun4i_tcon_get_clk_delay(mode, 1);
 210         regmap_update_bits(tcon->regs, SUN4I_TCON1_CTL_REG,
 211                            SUN4I_TCON1_CTL_CLK_DELAY_MASK,
 212                            SUN4I_TCON1_CTL_CLK_DELAY(clk_delay));
 213
 214         /* Set interlaced mode */
 215         if (mode->flags & DRM_MODE_FLAG_INTERLACE)
 216                 val = SUN4I_TCON1_CTL_INTERLACE_ENABLE;
 217         else
 218                 val = 0;
 219         regmap_update_bits(tcon->regs, SUN4I_TCON1_CTL_REG,
 220                            SUN4I_TCON1_CTL_INTERLACE_ENABLE,
 221                            val);
 222
 223         /* Set the input resolution */
 224         regmap_write(tcon->regs, SUN4I_TCON1_BASIC0_REG,
 225                      SUN4I_TCON1_BASIC0_X(mode->crtc_hdisplay) |
 226                      SUN4I_TCON1_BASIC0_Y(mode->crtc_vdisplay));
 227
 228         /* Set the upscaling resolution */
 229         regmap_write(tcon->regs, SUN4I_TCON1_BASIC1_REG,
 230                      SUN4I_TCON1_BASIC1_X(mode->crtc_hdisplay) |
 231                      SUN4I_TCON1_BASIC1_Y(mode->crtc_vdisplay));
 232
 233         /* Set the output resolution */
 234         regmap_write(tcon->regs, SUN4I_TCON1_BASIC2_REG,
 235                      SUN4I_TCON1_BASIC2_X(mode->crtc_hdisplay) |
 236                      SUN4I_TCON1_BASIC2_Y(mode->crtc_vdisplay));
 237
 238         /* Set horizontal display timings */
 239         bp = mode->crtc_htotal - mode->crtc_hsync_end;
 240         DRM_DEBUG_DRIVER("Setting horizontal total %d, backporch %d\n",
 241                          mode->htotal, bp);
 242         regmap_write(tcon->regs, SUN4I_TCON1_BASIC3_REG,
 243                      SUN4I_TCON1_BASIC3_H_TOTAL(mode->crtc_htotal) |
 244                      SUN4I_TCON1_BASIC3_H_BACKPORCH(bp));
 245
 246         /* Set vertical display timings */
 247         bp = mode->crtc_vtotal - mode->crtc_vsync_end;
 248         DRM_DEBUG_DRIVER("Setting vertical total %d, backporch %d\n",
 249                          mode->vtotal, bp);
 250         regmap_write(tcon->regs, SUN4I_TCON1_BASIC4_REG,
 251                      SUN4I_TCON1_BASIC4_V_TOTAL(mode->vtotal) |
 252                      SUN4I_TCON1_BASIC4_V_BACKPORCH(bp));
 253
 254         /* Set Hsync and Vsync length */
 255         hsync = mode->crtc_hsync_end - mode->crtc_hsync_start;
 256         vsync = mode->crtc_vsync_end - mode->crtc_vsync_start;
 257         DRM_DEBUG_DRIVER("Setting HSYNC %d, VSYNC %d\n", hsync, vsync);
 258         regmap_write(tcon->regs, SUN4I_TCON1_BASIC5_REG,
 259                      SUN4I_TCON1_BASIC5_V_SYNC(vsync) |
 260                      SUN4I_TCON1_BASIC5_H_SYNC(hsync));
 261
 262         /* Map output pins to channel 1 */
 263         regmap_update_bits(tcon->regs, SUN4I_TCON_GCTL_REG,
 264                            SUN4I_TCON_GCTL_IOMAP_MASK,
 265                            SUN4I_TCON_GCTL_IOMAP_TCON1);
 266
 267         /*
 268          * FIXME: Undocumented bits
 269          */
 270         if (tcon->quirks->has_unknown_mux)
 271                 regmap_write(tcon->regs, SUN4I_TCON_MUX_CTRL_REG, 1);
 272 }
 273 EXPORT_SYMBOL(sun4i_tcon1_mode_set);
 274
 275 static void sun4i_tcon_finish_page_flip(struct drm_device *dev,
 276                                         struct sun4i_crtc *scrtc)
 277 {
 278         unsigned long flags;
 279
 280         spin_lock_irqsave(&dev->event_lock, flags);
 281         if (scrtc->event) {
 282                 drm_crtc_send_vblank_event(&scrtc->crtc, scrtc->event);
 283                 drm_crtc_vblank_put(&scrtc->crtc);
 284                 scrtc->event = NULL;
 285         }
 286         spin_unlock_irqrestore(&dev->event_lock, flags);
 287 }
 288
 289 static irqreturn_t sun4i_tcon_handler(int irq, void *private)
 290 {
 291         struct sun4i_tcon *tcon = private;
 292         struct drm_device *drm = tcon->drm;
 293         struct sun4i_drv *drv = drm->dev_private;
 294         struct sun4i_crtc *scrtc = drv->crtc;
 295         unsigned int status;
 296
 297         regmap_read(tcon->regs, SUN4I_TCON_GINT0_REG, &status);
 298
 299         if (!(status & (SUN4I_TCON_GINT0_VBLANK_INT(0) |
 300                         SUN4I_TCON_GINT0_VBLANK_INT(1))))
 301                 return IRQ_NONE;
 302
 303         drm_crtc_handle_vblank(&scrtc->crtc);
 304         sun4i_tcon_finish_page_flip(drm, scrtc);
 305
 306         /* Acknowledge the interrupt */
 307         regmap_update_bits(tcon->regs, SUN4I_TCON_GINT0_REG,
 308                            SUN4I_TCON_GINT0_VBLANK_INT(0) |
 309                            SUN4I_TCON_GINT0_VBLANK_INT(1),
 310                            0);
 311
 312         return IRQ_HANDLED;
 313 }
 314
 315 static int sun4i_tcon_init_clocks(struct device *dev,
 316                                   struct sun4i_tcon *tcon)
 317 {
 318         tcon->clk = devm_clk_get(dev, "ahb");
 319         if (IS_ERR(tcon->clk)) {
 320                 dev_err(dev, "Couldn't get the TCON bus clock\n");
 321                 return PTR_ERR(tcon->clk);
 322         }
 323         clk_prepare_enable(tcon->clk);
 324
 325         tcon->sclk0 = devm_clk_get(dev, "tcon-ch0");
 326         if (IS_ERR(tcon->sclk0)) {
 327                 dev_err(dev, "Couldn't get the TCON channel 0 clock\n");
 328                 return PTR_ERR(tcon->sclk0);
 329         }
 330
 331         if (tcon->quirks->has_channel_1) {
 332                 tcon->sclk1 = devm_clk_get(dev, "tcon-ch1");
 333                 if (IS_ERR(tcon->sclk1)) {
 334                         dev_err(dev, "Couldn't get the TCON channel 1 clock\n");
 335                         return PTR_ERR(tcon->sclk1);
 336                 }
 337         }
 338
 339         return sun4i_dclk_create(dev, tcon);
 340 }
 341
 342 static void sun4i_tcon_free_clocks(struct sun4i_tcon *tcon)
 343 {
 344         sun4i_dclk_free(tcon);
 345         clk_disable_unprepare(tcon->clk);
 346 }
 347
 348 static int sun4i_tcon_init_irq(struct device *dev,
 349                                struct sun4i_tcon *tcon)
 350 {
 351         struct platform_device *pdev = to_platform_device(dev);
 352         int irq, ret;
 353
 354         irq = platform_get_irq(pdev, 0);
 355         if (irq < 0) {
 356                 dev_err(dev, "Couldn't retrieve the TCON interrupt\n");
 357                 return irq;
 358         }
 359
 360         ret = devm_request_irq(dev, irq, sun4i_tcon_handler, 0,
 361                                dev_name(dev), tcon);
 362         if (ret) {
 363                 dev_err(dev, "Couldn't request the IRQ\n");
 364                 return ret;
 365         }
 366
 367         return 0;
 368 }
 369
 370 static struct regmap_config sun4i_tcon_regmap_config = {
 371         .reg_bits       = 32,
 372         .val_bits       = 32,
 373         .reg_stride     = 4,
 374         .max_register   = 0x800,
 375 };
 376
 377 static int sun4i_tcon_init_regmap(struct device *dev,
 378                                   struct sun4i_tcon *tcon)
 379 {
 380         struct platform_device *pdev = to_platform_device(dev);
 381         struct resource *res;
 382         void __iomem *regs;
 383
 384         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 385         regs = devm_ioremap_resource(dev, res);
 386         if (IS_ERR(regs))
 387                 return PTR_ERR(regs);
 388
 389         tcon->regs = devm_regmap_init_mmio(dev, regs,
 390                                            &sun4i_tcon_regmap_config);
 391         if (IS_ERR(tcon->regs)) {
 392                 dev_err(dev, "Couldn't create the TCON regmap\n");
 393                 return PTR_ERR(tcon->regs);
 394         }
 395
 396         /* Make sure the TCON is disabled and all IRQs are off */
 397         regmap_write(tcon->regs, SUN4I_TCON_GCTL_REG, 0);
 398         regmap_write(tcon->regs, SUN4I_TCON_GINT0_REG, 0);
 399         regmap_write(tcon->regs, SUN4I_TCON_GINT1_REG, 0);
 400
 401         /* Disable IO lines and set them to tristate */
 402         regmap_write(tcon->regs, SUN4I_TCON0_IO_TRI_REG, ~0);
 403         regmap_write(tcon->regs, SUN4I_TCON1_IO_TRI_REG, ~0);
 404
 405         return 0;
 406 }
 407
 408 struct drm_panel *sun4i_tcon_find_panel(struct device_node *node)
 409 {
 410         struct device_node *port, *remote, *child;
 411         struct device_node *end_node = NULL;
 412
 413         /* Inputs are listed first, then outputs */
 414         port = of_graph_get_port_by_id(node, 1);
 415
 416         /*
 417          * Our first output is the RGB interface where the panel will
 418          * be connected.
 419          */
 420         for_each_child_of_node(port, child) {
 421                 u32 reg;
 422
 423                 of_property_read_u32(child, "reg", &reg);
 424                 if (reg == 0)
 425                         end_node = child;
 426         }
 427
 428         if (!end_node) {
 429                 DRM_DEBUG_DRIVER("Missing panel endpoint\n");
 430                 return ERR_PTR(-ENODEV);
 431         }
 432
 433         remote = of_graph_get_remote_port_parent(end_node);
 434         if (!remote) {
 435                 DRM_DEBUG_DRIVER("Unable to parse remote node\n");
 436                 return ERR_PTR(-EINVAL);
 437         }
 438
 439         return of_drm_find_panel(remote) ?: ERR_PTR(-EPROBE_DEFER);
 440 }
 441
 442 struct drm_bridge *sun4i_tcon_find_bridge(struct device_node *node)
 443 {
 444         struct device_node *port, *remote, *child;
 445         struct device_node *end_node = NULL;
 446
 447         /* Inputs are listed first, then outputs */
 448         port = of_graph_get_port_by_id(node, 1);
 449
 450         /*
 451          * Our first output is the RGB interface where the panel will
 452          * be connected.
 453          */
 454         for_each_child_of_node(port, child) {
 455                 u32 reg;
 456
 457                 of_property_read_u32(child, "reg", &reg);
 458                 if (reg == 0)
 459                         end_node = child;
 460         }
 461
 462         if (!end_node) {
 463                 DRM_DEBUG_DRIVER("Missing bridge endpoint\n");
 464                 return ERR_PTR(-ENODEV);
 465         }
 466
 467         remote = of_graph_get_remote_port_parent(end_node);
 468         if (!remote) {
 469                 DRM_DEBUG_DRIVER("Enable to parse remote node\n");
 470                 return ERR_PTR(-EINVAL);
 471         }
 472
 473         return of_drm_find_bridge(remote) ?: ERR_PTR(-EPROBE_DEFER);
 474 }
 475
 476 static int sun4i_tcon_bind(struct device *dev, struct device *master,
 477                            void *data)
 478 {
 479         struct drm_device *drm = data;
 480         struct sun4i_drv *drv = drm->dev_private;
 481         struct sun4i_tcon *tcon;
 482         int ret;
 483
 484         tcon = devm_kzalloc(dev, sizeof(*tcon), GFP_KERNEL);
 485         if (!tcon)
 486                 return -ENOMEM;
 487         dev_set_drvdata(dev, tcon);
 488         drv->tcon = tcon;
 489         tcon->drm = drm;
 490         tcon->dev = dev;
 491         tcon->quirks = of_device_get_match_data(dev);
 492
 493         tcon->lcd_rst = devm_reset_control_get(dev, "lcd");
 494         if (IS_ERR(tcon->lcd_rst)) {
 495                 dev_err(dev, "Couldn't get our reset line\n");
 496                 return PTR_ERR(tcon->lcd_rst);
 497         }
 498
 499         /* Make sure our TCON is reset */
 500         if (!reset_control_status(tcon->lcd_rst))
 501                 reset_control_assert(tcon->lcd_rst);
 502
 503         ret = reset_control_deassert(tcon->lcd_rst);
 504         if (ret) {
 505                 dev_err(dev, "Couldn't deassert our reset line\n");
 506                 return ret;
 507         }
 508
 509         ret = sun4i_tcon_init_regmap(dev, tcon);
 510         if (ret) {
 511                 dev_err(dev, "Couldn't init our TCON regmap\n");
 512                 goto err_assert_reset;
 513         }
 514
 515         ret = sun4i_tcon_init_clocks(dev, tcon);
 516         if (ret) {
 517                 dev_err(dev, "Couldn't init our TCON clocks\n");
 518                 goto err_assert_reset;
 519         }
 520
 521         ret = sun4i_tcon_init_irq(dev, tcon);
 522         if (ret) {
 523                 dev_err(dev, "Couldn't init our TCON interrupts\n");
 524                 goto err_free_clocks;
 525         }
 526
 527         ret = sun4i_rgb_init(drm);
 528         if (ret < 0)
 529                 goto err_free_clocks;
 530
 531         return 0;
 532
 533 err_free_clocks:
 534         sun4i_tcon_free_clocks(tcon);
 535 err_assert_reset:
 536         reset_control_assert(tcon->lcd_rst);
 537         return ret;
 538 }
 539
 540 static void sun4i_tcon_unbind(struct device *dev, struct device *master,
 541                               void *data)
 542 {
 543         struct sun4i_tcon *tcon = dev_get_drvdata(dev);
 544
 545         sun4i_tcon_free_clocks(tcon);
 546 }
 547
 548 static const struct component_ops sun4i_tcon_ops = {
 549         .bind   = sun4i_tcon_bind,
 550         .unbind = sun4i_tcon_unbind,
 551 };
 552
 553 static int sun4i_tcon_probe(struct platform_device *pdev)
 554 {
 555         struct device_node *node = pdev->dev.of_node;
 556         struct drm_bridge *bridge;
 557         struct drm_panel *panel;
 558
 559         /*
 560          * Neither the bridge or the panel is ready.
 561          * Defer the probe.
 562          */
 563         panel = sun4i_tcon_find_panel(node);
 564         bridge = sun4i_tcon_find_bridge(node);
 565
 566         /*
 567          * If we don't have a panel endpoint, just go on
 568          */
 569         if ((PTR_ERR(panel) == -EPROBE_DEFER) &&
 570             (PTR_ERR(bridge) == -EPROBE_DEFER)) {
 571                 DRM_DEBUG_DRIVER("Still waiting for our panel/bridge. Deferring...\n");
 572                 return -EPROBE_DEFER;
 573         }
 574
 575         return component_add(&pdev->dev, &sun4i_tcon_ops);
 576 }
 577
 578 static int sun4i_tcon_remove(struct platform_device *pdev)
 579 {
 580         component_del(&pdev->dev, &sun4i_tcon_ops);
 581
 582         return 0;
 583 }
 584
 585 static const struct sun4i_tcon_quirks sun5i_a13_quirks = {
 586         .has_unknown_mux = true,
 587         .has_channel_1  = true,
 588 };
 589
 590 static const struct sun4i_tcon_quirks sun6i_a31_quirks = {
 591         .has_channel_1  = true,
 592 };
 593
 594 static const struct sun4i_tcon_quirks sun6i_a31s_quirks = {
 595         .has_channel_1  = true,
 596 };
 597
 598 static const struct sun4i_tcon_quirks sun8i_a33_quirks = {
 599         /* nothing is supported */
 600 };
 601
 602 static const struct of_device_id sun4i_tcon_of_table[] = {
 603         { .compatible = "allwinner,sun5i-a13-tcon", .data = &sun5i_a13_quirks },
 604         { .compatible = "allwinner,sun6i-a31-tcon", .data = &sun6i_a31_quirks },
 605         { .compatible = "allwinner,sun6i-a31s-tcon", .data = &sun6i_a31s_quirks },
 606         { .compatible = "allwinner,sun8i-a33-tcon", .data = &sun8i_a33_quirks },
 607         { }
 608 };
 609 MODULE_DEVICE_TABLE(of, sun4i_tcon_of_table);
 610
 611 static struct platform_driver sun4i_tcon_platform_driver = {
 612         .probe          = sun4i_tcon_probe,
 613         .remove         = sun4i_tcon_remove,
 614         .driver         = {
 615                 .name           = "sun4i-tcon",
 616                 .of_match_table = sun4i_tcon_of_table,
 617         },
 618 };
 619 module_platform_driver(sun4i_tcon_platform_driver);
 620
 621 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
 622 MODULE_DESCRIPTION("Allwinner A10 Timing Controller Driver");
 623 MODULE_LICENSE("GPL");