drivers/gpu/drm/tilcdc/tilcdc_panel.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2012 Texas Instruments
   4  * Author: Rob Clark <robdclark@gmail.com>
   5  */
   6
   7 #include <linux/gpio/consumer.h>
   8 #include <linux/pinctrl/consumer.h>
   9 #include <linux/platform_device.h>
  10
  11 #include <video/display_timing.h>
  12 #include <video/of_display_timing.h>
  13 #include <video/videomode.h>
  14
  15 #include <drm/drm_atomic_state_helper.h>
  16 #include <drm/drm_connector.h>
  17 #include <drm/drm_modeset_helper_vtables.h>
  18 #include <drm/drm_probe_helper.h>
  19
  20 #include "tilcdc_drv.h"
  21 #include "tilcdc_panel.h"
  22
  23 struct panel_module {
  24         struct tilcdc_module base;
  25         struct tilcdc_panel_info *info;
  26         struct display_timings *timings;
  27         struct backlight_device *backlight;
  28         struct gpio_desc *enable_gpio;
  29 };
  30 #define to_panel_module(x) container_of(x, struct panel_module, base)
  31
  32
  33 /*
  34  * Encoder:
  35  */
  36
  37 struct panel_encoder {
  38         struct drm_encoder base;
  39         struct panel_module *mod;
  40 };
  41 #define to_panel_encoder(x) container_of(x, struct panel_encoder, base)
  42
  43 static void panel_encoder_dpms(struct drm_encoder *encoder, int mode)
  44 {
  45         struct panel_encoder *panel_encoder = to_panel_encoder(encoder);
  46         struct backlight_device *backlight = panel_encoder->mod->backlight;
  47         struct gpio_desc *gpio = panel_encoder->mod->enable_gpio;
  48
  49         if (backlight) {
  50                 backlight->props.power = mode == DRM_MODE_DPMS_ON ?
  51                                          FB_BLANK_UNBLANK : FB_BLANK_POWERDOWN;
  52                 backlight_update_status(backlight);
  53         }
  54
  55         if (gpio)
  56                 gpiod_set_value_cansleep(gpio,
  57                                          mode == DRM_MODE_DPMS_ON ? 1 : 0);
  58 }
  59
  60 static void panel_encoder_prepare(struct drm_encoder *encoder)
  61 {
  62         panel_encoder_dpms(encoder, DRM_MODE_DPMS_OFF);
  63 }
  64
  65 static void panel_encoder_commit(struct drm_encoder *encoder)
  66 {
  67         panel_encoder_dpms(encoder, DRM_MODE_DPMS_ON);
  68 }
  69
  70 static void panel_encoder_mode_set(struct drm_encoder *encoder,
  71                 struct drm_display_mode *mode,
  72                 struct drm_display_mode *adjusted_mode)
  73 {
  74         /* nothing needed */
  75 }
  76
  77 static const struct drm_encoder_funcs panel_encoder_funcs = {
  78                 .destroy        = drm_encoder_cleanup,
  79 };
  80
  81 static const struct drm_encoder_helper_funcs panel_encoder_helper_funcs = {
  82                 .dpms           = panel_encoder_dpms,
  83                 .prepare        = panel_encoder_prepare,
  84                 .commit         = panel_encoder_commit,
  85                 .mode_set       = panel_encoder_mode_set,
  86 };
  87
  88 static struct drm_encoder *panel_encoder_create(struct drm_device *dev,
  89                 struct panel_module *mod)
  90 {
  91         struct panel_encoder *panel_encoder;
  92         struct drm_encoder *encoder;
  93         int ret;
  94
  95         panel_encoder = devm_kzalloc(dev->dev, sizeof(*panel_encoder),
  96                                      GFP_KERNEL);
  97         if (!panel_encoder)
  98                 return NULL;
  99
 100         panel_encoder->mod = mod;
 101
 102         encoder = &panel_encoder->base;
 103         encoder->possible_crtcs = 1;
 104
 105         ret = drm_encoder_init(dev, encoder, &panel_encoder_funcs,
 106                         DRM_MODE_ENCODER_LVDS, NULL);
 107         if (ret < 0)
 108                 goto fail;
 109
 110         drm_encoder_helper_add(encoder, &panel_encoder_helper_funcs);
 111
 112         return encoder;
 113
 114 fail:
 115         drm_encoder_cleanup(encoder);
 116         return NULL;
 117 }
 118
 119 /*
 120  * Connector:
 121  */
 122
 123 struct panel_connector {
 124         struct drm_connector base;
 125
 126         struct drm_encoder *encoder;  /* our connected encoder */
 127         struct panel_module *mod;
 128 };
 129 #define to_panel_connector(x) container_of(x, struct panel_connector, base)
 130
 131
 132 static void panel_connector_destroy(struct drm_connector *connector)
 133 {
 134         drm_connector_unregister(connector);
 135         drm_connector_cleanup(connector);
 136 }
 137
 138 static int panel_connector_get_modes(struct drm_connector *connector)
 139 {
 140         struct drm_device *dev = connector->dev;
 141         struct panel_connector *panel_connector = to_panel_connector(connector);
 142         struct display_timings *timings = panel_connector->mod->timings;
 143         int i;
 144
 145         for (i = 0; i < timings->num_timings; i++) {
 146                 struct drm_display_mode *mode = drm_mode_create(dev);
 147                 struct videomode vm;
 148
 149                 if (videomode_from_timings(timings, &vm, i))
 150                         break;
 151
 152                 drm_display_mode_from_videomode(&vm, mode);
 153
 154                 mode->type = DRM_MODE_TYPE_DRIVER;
 155
 156                 if (timings->native_mode == i)
 157                         mode->type |= DRM_MODE_TYPE_PREFERRED;
 158
 159                 drm_mode_set_name(mode);
 160                 drm_mode_probed_add(connector, mode);
 161         }
 162
 163         return i;
 164 }
 165
 166 static int panel_connector_mode_valid(struct drm_connector *connector,
 167                   struct drm_display_mode *mode)
 168 {
 169         struct tilcdc_drm_private *priv = connector->dev->dev_private;
 170         /* our only constraints are what the crtc can generate: */
 171         return tilcdc_crtc_mode_valid(priv->crtc, mode);
 172 }
 173
 174 static struct drm_encoder *panel_connector_best_encoder(
 175                 struct drm_connector *connector)
 176 {
 177         struct panel_connector *panel_connector = to_panel_connector(connector);
 178         return panel_connector->encoder;
 179 }
 180
 181 static const struct drm_connector_funcs panel_connector_funcs = {
 182         .destroy            = panel_connector_destroy,
 183         .fill_modes         = drm_helper_probe_single_connector_modes,
 184         .reset              = drm_atomic_helper_connector_reset,
 185         .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 186         .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 187 };
 188
 189 static const struct drm_connector_helper_funcs panel_connector_helper_funcs = {
 190         .get_modes          = panel_connector_get_modes,
 191         .mode_valid         = panel_connector_mode_valid,
 192         .best_encoder       = panel_connector_best_encoder,
 193 };
 194
 195 static struct drm_connector *panel_connector_create(struct drm_device *dev,
 196                 struct panel_module *mod, struct drm_encoder *encoder)
 197 {
 198         struct panel_connector *panel_connector;
 199         struct drm_connector *connector;
 200         int ret;
 201
 202         panel_connector = devm_kzalloc(dev->dev, sizeof(*panel_connector),
 203                                        GFP_KERNEL);
 204         if (!panel_connector)
 205                 return NULL;
 206
 207         panel_connector->encoder = encoder;
 208         panel_connector->mod = mod;
 209
 210         connector = &panel_connector->base;
 211
 212         drm_connector_init(dev, connector, &panel_connector_funcs,
 213                         DRM_MODE_CONNECTOR_LVDS);
 214         drm_connector_helper_add(connector, &panel_connector_helper_funcs);
 215
 216         connector->interlace_allowed = 0;
 217         connector->doublescan_allowed = 0;
 218
 219         ret = drm_connector_attach_encoder(connector, encoder);
 220         if (ret)
 221                 goto fail;
 222
 223         return connector;
 224
 225 fail:
 226         panel_connector_destroy(connector);
 227         return NULL;
 228 }
 229
 230 /*
 231  * Module:
 232  */
 233
 234 static int panel_modeset_init(struct tilcdc_module *mod, struct drm_device *dev)
 235 {
 236         struct panel_module *panel_mod = to_panel_module(mod);
 237         struct tilcdc_drm_private *priv = dev->dev_private;
 238         struct drm_encoder *encoder;
 239         struct drm_connector *connector;
 240
 241         encoder = panel_encoder_create(dev, panel_mod);
 242         if (!encoder)
 243                 return -ENOMEM;
 244
 245         connector = panel_connector_create(dev, panel_mod, encoder);
 246         if (!connector)
 247                 return -ENOMEM;
 248
 249         priv->encoders[priv->num_encoders++] = encoder;
 250         priv->connectors[priv->num_connectors++] = connector;
 251
 252         tilcdc_crtc_set_panel_info(priv->crtc,
 253                                    to_panel_encoder(encoder)->mod->info);
 254
 255         return 0;
 256 }
 257
 258 static const struct tilcdc_module_ops panel_module_ops = {
 259                 .modeset_init = panel_modeset_init,
 260 };
 261
 262 /*
 263  * Device:
 264  */
 265
 266 /* maybe move this somewhere common if it is needed by other outputs? */
 267 static struct tilcdc_panel_info *of_get_panel_info(struct device_node *np)
 268 {
 269         struct device_node *info_np;
 270         struct tilcdc_panel_info *info;
 271         int ret = 0;
 272
 273         if (!np) {
 274                 pr_err("%s: no devicenode given\n", __func__);
 275                 return NULL;
 276         }
 277
 278         info_np = of_get_child_by_name(np, "panel-info");
 279         if (!info_np) {
 280                 pr_err("%s: could not find panel-info node\n", __func__);
 281                 return NULL;
 282         }
 283
 284         info = kzalloc(sizeof(*info), GFP_KERNEL);
 285         if (!info)
 286                 goto put_node;
 287
 288         ret |= of_property_read_u32(info_np, "ac-bias", &info->ac_bias);
 289         ret |= of_property_read_u32(info_np, "ac-bias-intrpt", &info->ac_bias_intrpt);
 290         ret |= of_property_read_u32(info_np, "dma-burst-sz", &info->dma_burst_sz);
 291         ret |= of_property_read_u32(info_np, "bpp", &info->bpp);
 292         ret |= of_property_read_u32(info_np, "fdd", &info->fdd);
 293         ret |= of_property_read_u32(info_np, "sync-edge", &info->sync_edge);
 294         ret |= of_property_read_u32(info_np, "sync-ctrl", &info->sync_ctrl);
 295         ret |= of_property_read_u32(info_np, "raster-order", &info->raster_order);
 296         ret |= of_property_read_u32(info_np, "fifo-th", &info->fifo_th);
 297
 298         /* optional: */
 299         info->tft_alt_mode      = of_property_read_bool(info_np, "tft-alt-mode");
 300         info->invert_pxl_clk    = of_property_read_bool(info_np, "invert-pxl-clk");
 301
 302         if (ret) {
 303                 pr_err("%s: error reading panel-info properties\n", __func__);
 304                 kfree(info);
 305                 info = NULL;
 306         }
 307
 308 put_node:
 309         of_node_put(info_np);
 310         return info;
 311 }
 312
 313 static int panel_probe(struct platform_device *pdev)
 314 {
 315         struct device_node *bl_node, *node = pdev->dev.of_node;
 316         struct panel_module *panel_mod;
 317         struct tilcdc_module *mod;
 318         struct pinctrl *pinctrl;
 319         int ret;
 320
 321         /* bail out early if no DT data: */
 322         if (!node) {
 323                 dev_err(&pdev->dev, "device-tree data is missing\n");
 324                 return -ENXIO;
 325         }
 326
 327         panel_mod = devm_kzalloc(&pdev->dev, sizeof(*panel_mod), GFP_KERNEL);
 328         if (!panel_mod)
 329                 return -ENOMEM;
 330
 331         bl_node = of_parse_phandle(node, "backlight", 0);
 332         if (bl_node) {
 333                 panel_mod->backlight = of_find_backlight_by_node(bl_node);
 334                 of_node_put(bl_node);
 335
 336                 if (!panel_mod->backlight)
 337                         return -EPROBE_DEFER;
 338
 339                 dev_info(&pdev->dev, "found backlight\n");
 340         }
 341
 342         panel_mod->enable_gpio = devm_gpiod_get_optional(&pdev->dev, "enable",
 343                                                          GPIOD_OUT_LOW);
 344         if (IS_ERR(panel_mod->enable_gpio)) {
 345                 ret = PTR_ERR(panel_mod->enable_gpio);
 346                 dev_err(&pdev->dev, "failed to request enable GPIO\n");
 347                 goto fail_backlight;
 348         }
 349
 350         if (panel_mod->enable_gpio)
 351                 dev_info(&pdev->dev, "found enable GPIO\n");
 352
 353         mod = &panel_mod->base;
 354         pdev->dev.platform_data = mod;
 355
 356         tilcdc_module_init(mod, "panel", &panel_module_ops);
 357
 358         pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
 359         if (IS_ERR(pinctrl))
 360                 dev_warn(&pdev->dev, "pins are not configured\n");
 361
 362         panel_mod->timings = of_get_display_timings(node);
 363         if (!panel_mod->timings) {
 364                 dev_err(&pdev->dev, "could not get panel timings\n");
 365                 ret = -EINVAL;
 366                 goto fail_free;
 367         }
 368
 369         panel_mod->info = of_get_panel_info(node);
 370         if (!panel_mod->info) {
 371                 dev_err(&pdev->dev, "could not get panel info\n");
 372                 ret = -EINVAL;
 373                 goto fail_timings;
 374         }
 375
 376         return 0;
 377
 378 fail_timings:
 379         display_timings_release(panel_mod->timings);
 380
 381 fail_free:
 382         tilcdc_module_cleanup(mod);
 383
 384 fail_backlight:
 385         if (panel_mod->backlight)
 386                 put_device(&panel_mod->backlight->dev);
 387         return ret;
 388 }
 389
 390 static int panel_remove(struct platform_device *pdev)
 391 {
 392         struct tilcdc_module *mod = dev_get_platdata(&pdev->dev);
 393         struct panel_module *panel_mod = to_panel_module(mod);
 394         struct backlight_device *backlight = panel_mod->backlight;
 395
 396         if (backlight)
 397                 put_device(&backlight->dev);
 398
 399         display_timings_release(panel_mod->timings);
 400
 401         tilcdc_module_cleanup(mod);
 402         kfree(panel_mod->info);
 403
 404         return 0;
 405 }
 406
 407 static const struct of_device_id panel_of_match[] = {
 408                 { .compatible = "ti,tilcdc,panel", },
 409                 { },
 410 };
 411
 412 struct platform_driver panel_driver = {
 413         .probe = panel_probe,
 414         .remove = panel_remove,
 415         .driver = {
 416                 .owner = THIS_MODULE,
 417                 .name = "tilcdc-panel",
 418                 .of_match_table = panel_of_match,
 419         },
 420 };
 421
 422 int __init tilcdc_panel_init(void)
 423 {
 424         return platform_driver_register(&panel_driver);
 425 }
 426
 427 void __exit tilcdc_panel_fini(void)
 428 {
 429         platform_driver_unregister(&panel_driver);
 430 }