drivers/gpu/drm/sti/sti_dvo.c

   1 /*
   2  * Copyright (C) STMicroelectronics SA 2014
   3  * Author: Vincent Abriou <[email protected]> for STMicroelectronics.
   4  * License terms:  GNU General Public License (GPL), version 2
   5  */
   6
   7 #include <linux/clk.h>
   8 #include <linux/component.h>
   9 #include <linux/module.h>
  10 #include <linux/of_gpio.h>
  11 #include <linux/platform_device.h>
  12
  13 #include <drm/drmP.h>
  14 #include <drm/drm_crtc_helper.h>
  15 #include <drm/drm_panel.h>
  16
  17 #include "sti_awg_utils.h"
  18 #include "sti_mixer.h"
  19
  20 /* DVO registers */
  21 #define DVO_AWG_DIGSYNC_CTRL      0x0000
  22 #define DVO_DOF_CFG               0x0004
  23 #define DVO_LUT_PROG_LOW          0x0008
  24 #define DVO_LUT_PROG_MID          0x000C
  25 #define DVO_LUT_PROG_HIGH         0x0010
  26 #define DVO_DIGSYNC_INSTR_I       0x0100
  27
  28 #define DVO_AWG_CTRL_EN           BIT(0)
  29 #define DVO_AWG_FRAME_BASED_SYNC  BIT(2)
  30
  31 #define DVO_DOF_EN_LOWBYTE        BIT(0)
  32 #define DVO_DOF_EN_MIDBYTE        BIT(1)
  33 #define DVO_DOF_EN_HIGHBYTE       BIT(2)
  34 #define DVO_DOF_EN                BIT(6)
  35 #define DVO_DOF_MOD_COUNT_SHIFT   8
  36
  37 #define DVO_LUT_ZERO              0
  38 #define DVO_LUT_Y_G               1
  39 #define DVO_LUT_Y_G_DEL           2
  40 #define DVO_LUT_CB_B              3
  41 #define DVO_LUT_CB_B_DEL          4
  42 #define DVO_LUT_CR_R              5
  43 #define DVO_LUT_CR_R_DEL          6
  44 #define DVO_LUT_HOLD              7
  45
  46 struct dvo_config {
  47         u32 flags;
  48         u32 lowbyte;
  49         u32 midbyte;
  50         u32 highbyte;
  51         int (*awg_fwgen_fct)(
  52                         struct awg_code_generation_params *fw_gen_params,
  53                         struct awg_timing *timing);
  54 };
  55
  56 static struct dvo_config rgb_24bit_de_cfg = {
  57         .flags         = (0L << DVO_DOF_MOD_COUNT_SHIFT),
  58         .lowbyte       = DVO_LUT_CR_R,
  59         .midbyte       = DVO_LUT_Y_G,
  60         .highbyte      = DVO_LUT_CB_B,
  61         .awg_fwgen_fct = sti_awg_generate_code_data_enable_mode,
  62 };
  63
  64 /**
  65  * STI digital video output structure
  66  *
  67  * @dev: driver device
  68  * @drm_dev: pointer to drm device
  69  * @mode: current display mode selected
  70  * @regs: dvo registers
  71  * @clk_pix: pixel clock for dvo
  72  * @clk: clock for dvo
  73  * @clk_main_parent: dvo parent clock if main path used
  74  * @clk_aux_parent: dvo parent clock if aux path used
  75  * @panel_node: panel node reference from device tree
  76  * @panel: reference to the panel connected to the dvo
  77  * @enabled: true if dvo is enabled else false
  78  * @encoder: drm_encoder it is bound
  79  */
  80 struct sti_dvo {
  81         struct device dev;
  82         struct drm_device *drm_dev;
  83         struct drm_display_mode mode;
  84         void __iomem *regs;
  85         struct clk *clk_pix;
  86         struct clk *clk;
  87         struct clk *clk_main_parent;
  88         struct clk *clk_aux_parent;
  89         struct device_node *panel_node;
  90         struct drm_panel *panel;
  91         struct dvo_config *config;
  92         bool enabled;
  93         struct drm_encoder *encoder;
  94         struct drm_bridge *bridge;
  95 };
  96
  97 struct sti_dvo_connector {
  98         struct drm_connector drm_connector;
  99         struct drm_encoder *encoder;
 100         struct sti_dvo *dvo;
 101 };
 102
 103 #define to_sti_dvo_connector(x) \
 104         container_of(x, struct sti_dvo_connector, drm_connector)
 105
 106 #define BLANKING_LEVEL 16
 107 int dvo_awg_generate_code(struct sti_dvo *dvo, u8 *ram_size, u32 *ram_code)
 108 {
 109         struct drm_display_mode *mode = &dvo->mode;
 110         struct dvo_config *config = dvo->config;
 111         struct awg_code_generation_params fw_gen_params;
 112         struct awg_timing timing;
 113
 114         fw_gen_params.ram_code = ram_code;
 115         fw_gen_params.instruction_offset = 0;
 116
 117         timing.total_lines = mode->vtotal;
 118         timing.active_lines = mode->vdisplay;
 119         timing.blanking_lines = mode->vsync_start - mode->vdisplay;
 120         timing.trailing_lines = mode->vtotal - mode->vsync_start;
 121         timing.total_pixels = mode->htotal;
 122         timing.active_pixels = mode->hdisplay;
 123         timing.blanking_pixels = mode->hsync_start - mode->hdisplay;
 124         timing.trailing_pixels = mode->htotal - mode->hsync_start;
 125         timing.blanking_level = BLANKING_LEVEL;
 126
 127         if (config->awg_fwgen_fct(&fw_gen_params, &timing)) {
 128                 DRM_ERROR("AWG firmware not properly generated\n");
 129                 return -EINVAL;
 130         }
 131
 132         *ram_size = fw_gen_params.instruction_offset;
 133
 134         return 0;
 135 }
 136
 137 /* Configure AWG, writing instructions
 138  *
 139  * @dvo: pointer to DVO structure
 140  * @awg_ram_code: pointer to AWG instructions table
 141  * @nb: nb of AWG instructions
 142  */
 143 static void dvo_awg_configure(struct sti_dvo *dvo, u32 *awg_ram_code, int nb)
 144 {
 145         int i;
 146
 147         DRM_DEBUG_DRIVER("\n");
 148
 149         for (i = 0; i < nb; i++)
 150                 writel(awg_ram_code[i],
 151                        dvo->regs + DVO_DIGSYNC_INSTR_I + i * 4);
 152         for (i = nb; i < AWG_MAX_INST; i++)
 153                 writel(0, dvo->regs + DVO_DIGSYNC_INSTR_I + i * 4);
 154
 155         writel(DVO_AWG_CTRL_EN, dvo->regs + DVO_AWG_DIGSYNC_CTRL);
 156 }
 157
 158 static void sti_dvo_disable(struct drm_bridge *bridge)
 159 {
 160         struct sti_dvo *dvo = bridge->driver_private;
 161
 162         if (!dvo->enabled)
 163                 return;
 164
 165         DRM_DEBUG_DRIVER("\n");
 166
 167         if (dvo->config->awg_fwgen_fct)
 168                 writel(0x00000000, dvo->regs + DVO_AWG_DIGSYNC_CTRL);
 169
 170         writel(0x00000000, dvo->regs + DVO_DOF_CFG);
 171
 172         if (dvo->panel)
 173                 dvo->panel->funcs->disable(dvo->panel);
 174
 175         /* Disable/unprepare dvo clock */
 176         clk_disable_unprepare(dvo->clk_pix);
 177         clk_disable_unprepare(dvo->clk);
 178
 179         dvo->enabled = false;
 180 }
 181
 182 static void sti_dvo_pre_enable(struct drm_bridge *bridge)
 183 {
 184         struct sti_dvo *dvo = bridge->driver_private;
 185         struct dvo_config *config = dvo->config;
 186         u32 val;
 187
 188         DRM_DEBUG_DRIVER("\n");
 189
 190         if (dvo->enabled)
 191                 return;
 192
 193         /* Make sure DVO is disabled */
 194         writel(0x00000000, dvo->regs + DVO_DOF_CFG);
 195         writel(0x00000000, dvo->regs + DVO_AWG_DIGSYNC_CTRL);
 196
 197         if (config->awg_fwgen_fct) {
 198                 u8 nb_instr;
 199                 u32 awg_ram_code[AWG_MAX_INST];
 200                 /* Configure AWG */
 201                 if (!dvo_awg_generate_code(dvo, &nb_instr, awg_ram_code))
 202                         dvo_awg_configure(dvo, awg_ram_code, nb_instr);
 203                 else
 204                         return;
 205         }
 206
 207         /* Prepare/enable clocks */
 208         if (clk_prepare_enable(dvo->clk_pix))
 209                 DRM_ERROR("Failed to prepare/enable dvo_pix clk\n");
 210         if (clk_prepare_enable(dvo->clk))
 211                 DRM_ERROR("Failed to prepare/enable dvo clk\n");
 212
 213         if (dvo->panel)
 214                 dvo->panel->funcs->enable(dvo->panel);
 215
 216         /* Set LUT */
 217         writel(config->lowbyte,  dvo->regs + DVO_LUT_PROG_LOW);
 218         writel(config->midbyte,  dvo->regs + DVO_LUT_PROG_MID);
 219         writel(config->highbyte, dvo->regs + DVO_LUT_PROG_HIGH);
 220
 221         /* Digital output formatter config */
 222         val = (config->flags | DVO_DOF_EN);
 223         writel(val, dvo->regs + DVO_DOF_CFG);
 224
 225         dvo->enabled = true;
 226 }
 227
 228 static void sti_dvo_set_mode(struct drm_bridge *bridge,
 229                              struct drm_display_mode *mode,
 230                              struct drm_display_mode *adjusted_mode)
 231 {
 232         struct sti_dvo *dvo = bridge->driver_private;
 233         struct sti_mixer *mixer = to_sti_mixer(dvo->encoder->crtc);
 234         int rate = mode->clock * 1000;
 235         struct clk *clkp;
 236         int ret;
 237
 238         DRM_DEBUG_DRIVER("\n");
 239
 240         memcpy(&dvo->mode, mode, sizeof(struct drm_display_mode));
 241
 242         /* According to the path used (main or aux), the dvo clocks should
 243          * have a different parent clock. */
 244         if (mixer->id == STI_MIXER_MAIN)
 245                 clkp = dvo->clk_main_parent;
 246         else
 247                 clkp = dvo->clk_aux_parent;
 248
 249         if (clkp) {
 250                 clk_set_parent(dvo->clk_pix, clkp);
 251                 clk_set_parent(dvo->clk, clkp);
 252         }
 253
 254         /* DVO clocks = compositor clock */
 255         ret = clk_set_rate(dvo->clk_pix, rate);
 256         if (ret < 0) {
 257                 DRM_ERROR("Cannot set rate (%dHz) for dvo_pix clk\n", rate);
 258                 return;
 259         }
 260
 261         ret = clk_set_rate(dvo->clk, rate);
 262         if (ret < 0) {
 263                 DRM_ERROR("Cannot set rate (%dHz) for dvo clk\n", rate);
 264                 return;
 265         }
 266
 267         /* For now, we only support 24bit data enable (DE) synchro format */
 268         dvo->config = &rgb_24bit_de_cfg;
 269 }
 270
 271 static void sti_dvo_bridge_nope(struct drm_bridge *bridge)
 272 {
 273         /* do nothing */
 274 }
 275
 276 static const struct drm_bridge_funcs sti_dvo_bridge_funcs = {
 277         .pre_enable = sti_dvo_pre_enable,
 278         .enable = sti_dvo_bridge_nope,
 279         .disable = sti_dvo_disable,
 280         .post_disable = sti_dvo_bridge_nope,
 281         .mode_set = sti_dvo_set_mode,
 282 };
 283
 284 static int sti_dvo_connector_get_modes(struct drm_connector *connector)
 285 {
 286         struct sti_dvo_connector *dvo_connector
 287                 = to_sti_dvo_connector(connector);
 288         struct sti_dvo *dvo = dvo_connector->dvo;
 289
 290         if (dvo->panel)
 291                 return dvo->panel->funcs->get_modes(dvo->panel);
 292
 293         return 0;
 294 }
 295
 296 #define CLK_TOLERANCE_HZ 50
 297
 298 static int sti_dvo_connector_mode_valid(struct drm_connector *connector,
 299                                         struct drm_display_mode *mode)
 300 {
 301         int target = mode->clock * 1000;
 302         int target_min = target - CLK_TOLERANCE_HZ;
 303         int target_max = target + CLK_TOLERANCE_HZ;
 304         int result;
 305         struct sti_dvo_connector *dvo_connector
 306                 = to_sti_dvo_connector(connector);
 307         struct sti_dvo *dvo = dvo_connector->dvo;
 308
 309         result = clk_round_rate(dvo->clk_pix, target);
 310
 311         DRM_DEBUG_DRIVER("target rate = %d => available rate = %d\n",
 312                          target, result);
 313
 314         if ((result < target_min) || (result > target_max)) {
 315                 DRM_DEBUG_DRIVER("dvo pixclk=%d not supported\n", target);
 316                 return MODE_BAD;
 317         }
 318
 319         return MODE_OK;
 320 }
 321
 322 struct drm_encoder *sti_dvo_best_encoder(struct drm_connector *connector)
 323 {
 324         struct sti_dvo_connector *dvo_connector
 325                 = to_sti_dvo_connector(connector);
 326
 327         /* Best encoder is the one associated during connector creation */
 328         return dvo_connector->encoder;
 329 }
 330
 331 static struct drm_connector_helper_funcs sti_dvo_connector_helper_funcs = {
 332         .get_modes = sti_dvo_connector_get_modes,
 333         .mode_valid = sti_dvo_connector_mode_valid,
 334         .best_encoder = sti_dvo_best_encoder,
 335 };
 336
 337 static enum drm_connector_status
 338 sti_dvo_connector_detect(struct drm_connector *connector, bool force)
 339 {
 340         struct sti_dvo_connector *dvo_connector
 341                 = to_sti_dvo_connector(connector);
 342         struct sti_dvo *dvo = dvo_connector->dvo;
 343
 344         DRM_DEBUG_DRIVER("\n");
 345
 346         if (!dvo->panel)
 347                 dvo->panel = of_drm_find_panel(dvo->panel_node);
 348
 349         if (dvo->panel)
 350                 if (!drm_panel_attach(dvo->panel, connector))
 351                         return connector_status_connected;
 352
 353         return connector_status_disconnected;
 354 }
 355
 356 static void sti_dvo_connector_destroy(struct drm_connector *connector)
 357 {
 358         struct sti_dvo_connector *dvo_connector
 359                 = to_sti_dvo_connector(connector);
 360
 361         drm_connector_unregister(connector);
 362         drm_connector_cleanup(connector);
 363         kfree(dvo_connector);
 364 }
 365
 366 static struct drm_connector_funcs sti_dvo_connector_funcs = {
 367         .dpms = drm_helper_connector_dpms,
 368         .fill_modes = drm_helper_probe_single_connector_modes,
 369         .detect = sti_dvo_connector_detect,
 370         .destroy = sti_dvo_connector_destroy,
 371 };
 372
 373 static struct drm_encoder *sti_dvo_find_encoder(struct drm_device *dev)
 374 {
 375         struct drm_encoder *encoder;
 376
 377         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 378                 if (encoder->encoder_type == DRM_MODE_ENCODER_LVDS)
 379                         return encoder;
 380         }
 381
 382         return NULL;
 383 }
 384
 385 static int sti_dvo_bind(struct device *dev, struct device *master, void *data)
 386 {
 387         struct sti_dvo *dvo = dev_get_drvdata(dev);
 388         struct drm_device *drm_dev = data;
 389         struct drm_encoder *encoder;
 390         struct sti_dvo_connector *connector;
 391         struct drm_connector *drm_connector;
 392         struct drm_bridge *bridge;
 393         int err;
 394
 395         /* Set the drm device handle */
 396         dvo->drm_dev = drm_dev;
 397
 398         encoder = sti_dvo_find_encoder(drm_dev);
 399         if (!encoder)
 400                 return -ENOMEM;
 401
 402         connector = devm_kzalloc(dev, sizeof(*connector), GFP_KERNEL);
 403         if (!connector)
 404                 return -ENOMEM;
 405
 406         connector->dvo = dvo;
 407
 408         bridge = devm_kzalloc(dev, sizeof(*bridge), GFP_KERNEL);
 409         if (!bridge)
 410                 return -ENOMEM;
 411
 412         bridge->driver_private = dvo;
 413         bridge->funcs = &sti_dvo_bridge_funcs;
 414         bridge->of_node = dvo->dev.of_node;
 415         err = drm_bridge_add(bridge);
 416         if (err) {
 417                 DRM_ERROR("Failed to add bridge\n");
 418                 return err;
 419         }
 420
 421         err = drm_bridge_attach(drm_dev, bridge);
 422         if (err) {
 423                 DRM_ERROR("Failed to attach bridge\n");
 424                 return err;
 425         }
 426
 427         dvo->bridge = bridge;
 428         encoder->bridge = bridge;
 429         connector->encoder = encoder;
 430         dvo->encoder = encoder;
 431
 432         drm_connector = (struct drm_connector *)connector;
 433
 434         drm_connector->polled = DRM_CONNECTOR_POLL_HPD;
 435
 436         drm_connector_init(drm_dev, drm_connector,
 437                            &sti_dvo_connector_funcs, DRM_MODE_CONNECTOR_LVDS);
 438         drm_connector_helper_add(drm_connector,
 439                                  &sti_dvo_connector_helper_funcs);
 440
 441         err = drm_connector_register(drm_connector);
 442         if (err)
 443                 goto err_connector;
 444
 445         err = drm_mode_connector_attach_encoder(drm_connector, encoder);
 446         if (err) {
 447                 DRM_ERROR("Failed to attach a connector to a encoder\n");
 448                 goto err_sysfs;
 449         }
 450
 451         return 0;
 452
 453 err_sysfs:
 454         drm_connector_unregister(drm_connector);
 455 err_connector:
 456         drm_bridge_remove(bridge);
 457         drm_connector_cleanup(drm_connector);
 458         return -EINVAL;
 459 }
 460
 461 static void sti_dvo_unbind(struct device *dev,
 462                            struct device *master, void *data)
 463 {
 464         struct sti_dvo *dvo = dev_get_drvdata(dev);
 465
 466         drm_bridge_remove(dvo->bridge);
 467 }
 468
 469 static const struct component_ops sti_dvo_ops = {
 470         .bind = sti_dvo_bind,
 471         .unbind = sti_dvo_unbind,
 472 };
 473
 474 static int sti_dvo_probe(struct platform_device *pdev)
 475 {
 476         struct device *dev = &pdev->dev;
 477         struct sti_dvo *dvo;
 478         struct resource *res;
 479         struct device_node *np = dev->of_node;
 480
 481         DRM_INFO("%s\n", __func__);
 482
 483         dvo = devm_kzalloc(dev, sizeof(*dvo), GFP_KERNEL);
 484         if (!dvo) {
 485                 DRM_ERROR("Failed to allocate memory for DVO\n");
 486                 return -ENOMEM;
 487         }
 488
 489         dvo->dev = pdev->dev;
 490
 491         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dvo-reg");
 492         if (!res) {
 493                 DRM_ERROR("Invalid dvo resource\n");
 494                 return -ENOMEM;
 495         }
 496         dvo->regs = devm_ioremap_nocache(dev, res->start,
 497                         resource_size(res));
 498         if (IS_ERR(dvo->regs))
 499                 return PTR_ERR(dvo->regs);
 500
 501         dvo->clk_pix = devm_clk_get(dev, "dvo_pix");
 502         if (IS_ERR(dvo->clk_pix)) {
 503                 DRM_ERROR("Cannot get dvo_pix clock\n");
 504                 return PTR_ERR(dvo->clk_pix);
 505         }
 506
 507         dvo->clk = devm_clk_get(dev, "dvo");
 508         if (IS_ERR(dvo->clk)) {
 509                 DRM_ERROR("Cannot get dvo clock\n");
 510                 return PTR_ERR(dvo->clk);
 511         }
 512
 513         dvo->clk_main_parent = devm_clk_get(dev, "main_parent");
 514         if (IS_ERR(dvo->clk_main_parent)) {
 515                 DRM_DEBUG_DRIVER("Cannot get main_parent clock\n");
 516                 dvo->clk_main_parent = NULL;
 517         }
 518
 519         dvo->clk_aux_parent = devm_clk_get(dev, "aux_parent");
 520         if (IS_ERR(dvo->clk_aux_parent)) {
 521                 DRM_DEBUG_DRIVER("Cannot get aux_parent clock\n");
 522                 dvo->clk_aux_parent = NULL;
 523         }
 524
 525         dvo->panel_node = of_parse_phandle(np, "sti,panel", 0);
 526         if (!dvo->panel_node)
 527                 DRM_ERROR("No panel associated to the dvo output\n");
 528
 529         platform_set_drvdata(pdev, dvo);
 530
 531         return component_add(&pdev->dev, &sti_dvo_ops);
 532 }
 533
 534 static int sti_dvo_remove(struct platform_device *pdev)
 535 {
 536         component_del(&pdev->dev, &sti_dvo_ops);
 537         return 0;
 538 }
 539
 540 static struct of_device_id dvo_of_match[] = {
 541         { .compatible = "st,stih407-dvo", },
 542         { /* end node */ }
 543 };
 544 MODULE_DEVICE_TABLE(of, dvo_of_match);
 545
 546 struct platform_driver sti_dvo_driver = {
 547         .driver = {
 548                 .name = "sti-dvo",
 549                 .owner = THIS_MODULE,
 550                 .of_match_table = dvo_of_match,
 551         },
 552         .probe = sti_dvo_probe,
 553         .remove = sti_dvo_remove,
 554 };
 555
 556 module_platform_driver(sti_dvo_driver);
 557
 558 MODULE_AUTHOR("Benjamin Gaignard <[email protected]>");
 559 MODULE_DESCRIPTION("STMicroelectronics SoC DRM driver");
 560 MODULE_LICENSE("GPL");