drivers/gpu/drm/panel/panel-arm-versatile.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Panel driver for the ARM Versatile family reference designs from
   4  * ARM Limited.
   5  *
   6  * Author:
   7  * Linus Walleij <linus.wallei@linaro.org>
   8  *
   9  * On the Versatile AB, these panels come mounted on daughterboards
  10  * named "IB1" or "IB2" (Interface Board 1 & 2 respectively.) They
  11  * are documented in ARM DUI 0225D Appendix C and D. These daughter
  12  * boards support TFT display panels.
  13  *
  14  * - The IB1 is a passive board where the display connector defines a
  15  *   few wires for encoding the display type for autodetection,
  16  *   suitable display settings can then be looked up from this setting.
  17  *   The magic bits can be read out from the system controller.
  18  *
  19  * - The IB2 is a more complex board intended for GSM phone development
  20  *   with some logic and a control register, which needs to be accessed
  21  *   and the board display needs to be turned on explicitly.
  22  *
  23  * On the Versatile PB, a special CLCD adaptor board is available
  24  * supporting the same displays as the Versatile AB, plus one more
  25  * Epson QCIF display.
  26  *
  27  */
  28 #include <drm/drmP.h>
  29 #include <drm/drm_panel.h>
  30
  31 #include <linux/bitops.h>
  32 #include <linux/init.h>
  33 #include <linux/kernel.h>
  34 #include <linux/mfd/syscon.h>
  35 #include <linux/module.h>
  36 #include <linux/platform_device.h>
  37 #include <linux/regmap.h>
  38
  39 #include <video/of_videomode.h>
  40 #include <video/videomode.h>
  41
  42 /*
  43  * This configuration register in the Versatile and RealView
  44  * family is uniformly present but appears more and more
  45  * unutilized starting with the RealView series.
  46  */
  47 #define SYS_CLCD                        0x50
  48
  49 /* The Versatile can detect the connected panel type */
  50 #define SYS_CLCD_CLCDID_MASK            (BIT(8)|BIT(9)|BIT(10)|BIT(11)|BIT(12))
  51 #define SYS_CLCD_ID_SANYO_3_8           (0x00 << 8)
  52 #define SYS_CLCD_ID_SHARP_8_4           (0x01 << 8)
  53 #define SYS_CLCD_ID_EPSON_2_2           (0x02 << 8)
  54 #define SYS_CLCD_ID_SANYO_2_5           (0x07 << 8)
  55 #define SYS_CLCD_ID_VGA                 (0x1f << 8)
  56
  57 /* IB2 control register for the Versatile daughterboard */
  58 #define IB2_CTRL                        0x00
  59 #define IB2_CTRL_LCD_SD                 BIT(1) /* 1 = shut down LCD */
  60 #define IB2_CTRL_LCD_BL_ON              BIT(0)
  61 #define IB2_CTRL_LCD_MASK               (BIT(0)|BIT(1))
  62
  63 /**
  64  * struct versatile_panel_type - lookup struct for the supported panels
  65  */
  66 struct versatile_panel_type {
  67         /**
  68          * @name: the name of this panel
  69          */
  70         const char *name;
  71         /**
  72          * @magic: the magic value from the detection register
  73          */
  74         u32 magic;
  75         /**
  76          * @mode: the DRM display mode for this panel
  77          */
  78         struct drm_display_mode mode;
  79         /**
  80          * @bus_flags: the DRM bus flags for this panel e.g. inverted clock
  81          */
  82         u32 bus_flags;
  83         /**
  84          * @width_mm: the panel width in mm
  85          */
  86         u32 width_mm;
  87         /**
  88          * @height_mm: the panel height in mm
  89          */
  90         u32 height_mm;
  91         /**
  92          * @ib2: the panel may be connected on an IB2 daughterboard
  93          */
  94         bool ib2;
  95 };
  96
  97 /**
  98  * struct versatile_panel - state container for the Versatile panels
  99  */
 100 struct versatile_panel {
 101         /**
 102          * @dev: the container device
 103          */
 104         struct device *dev;
 105         /**
 106          * @panel: the DRM panel instance for this device
 107          */
 108         struct drm_panel panel;
 109         /**
 110          * @panel_type: the Versatile panel type as detected
 111          */
 112         const struct versatile_panel_type *panel_type;
 113         /**
 114          * @map: map to the parent syscon where the main register reside
 115          */
 116         struct regmap *map;
 117         /**
 118          * @ib2_map: map to the IB2 syscon, if applicable
 119          */
 120         struct regmap *ib2_map;
 121 };
 122
 123 static const struct versatile_panel_type versatile_panels[] = {
 124         /*
 125          * Sanyo TM38QV67A02A - 3.8 inch QVGA (320x240) Color TFT
 126          * found on the Versatile AB IB1 connector or the Versatile
 127          * PB adaptor board connector.
 128          */
 129         {
 130                 .name = "Sanyo TM38QV67A02A",
 131                 .magic = SYS_CLCD_ID_SANYO_3_8,
 132                 .width_mm = 79,
 133                 .height_mm = 54,
 134                 .mode = {
 135                         .clock = 10000,
 136                         .hdisplay = 320,
 137                         .hsync_start = 320 + 6,
 138                         .hsync_end = 320 + 6 + 6,
 139                         .htotal = 320 + 6 + 6 + 6,
 140                         .vdisplay = 240,
 141                         .vsync_start = 240 + 5,
 142                         .vsync_end = 240 + 5 + 6,
 143                         .vtotal = 240 + 5 + 6 + 5,
 144                         .vrefresh = 116,
 145                         .flags = DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC,
 146                 },
 147         },
 148         /*
 149          * Sharp LQ084V1DG21 640x480 VGA Color TFT module
 150          * found on the Versatile AB IB1 connector or the Versatile
 151          * PB adaptor board connector.
 152          */
 153         {
 154                 .name = "Sharp LQ084V1DG21",
 155                 .magic = SYS_CLCD_ID_SHARP_8_4,
 156                 .width_mm = 171,
 157                 .height_mm = 130,
 158                 .mode = {
 159                         .clock = 25000,
 160                         .hdisplay = 640,
 161                         .hsync_start = 640 + 24,
 162                         .hsync_end = 640 + 24 + 96,
 163                         .htotal = 640 + 24 + 96 + 24,
 164                         .vdisplay = 480,
 165                         .vsync_start = 480 + 11,
 166                         .vsync_end = 480 + 11 + 2,
 167                         .vtotal = 480 + 11 + 2 + 32,
 168                         .vrefresh = 60,
 169                         .flags = DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC,
 170                 },
 171         },
 172         /*
 173          * Epson L2F50113T00 - 2.2 inch QCIF 176x220 Color TFT
 174          * found on the Versatile PB adaptor board connector.
 175          */
 176         {
 177                 .name = "Epson L2F50113T00",
 178                 .magic = SYS_CLCD_ID_EPSON_2_2,
 179                 .width_mm = 34,
 180                 .height_mm = 45,
 181                 .mode = {
 182                         .clock = 62500,
 183                         .hdisplay = 176,
 184                         .hsync_start = 176 + 2,
 185                         .hsync_end = 176 + 2 + 3,
 186                         .htotal = 176 + 2 + 3 + 3,
 187                         .vdisplay = 220,
 188                         .vsync_start = 220 + 0,
 189                         .vsync_end = 220 + 0 + 2,
 190                         .vtotal = 220 + 0 + 2 + 1,
 191                         .vrefresh = 390,
 192                         .flags = DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC,
 193                 },
 194                 .bus_flags = DRM_BUS_FLAG_PIXDATA_NEGEDGE,
 195         },
 196         /*
 197          * Sanyo ALR252RGT 240x320 portrait display found on the
 198          * Versatile AB IB2 daughterboard for GSM prototyping.
 199          */
 200         {
 201                 .name = "Sanyo ALR252RGT",
 202                 .magic = SYS_CLCD_ID_SANYO_2_5,
 203                 .width_mm = 37,
 204                 .height_mm = 50,
 205                 .mode = {
 206                         .clock = 5400,
 207                         .hdisplay = 240,
 208                         .hsync_start = 240 + 10,
 209                         .hsync_end = 240 + 10 + 10,
 210                         .htotal = 240 + 10 + 10 + 20,
 211                         .vdisplay = 320,
 212                         .vsync_start = 320 + 2,
 213                         .vsync_end = 320 + 2 + 2,
 214                         .vtotal = 320 + 2 + 2 + 2,
 215                         .vrefresh = 116,
 216                         .flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,
 217                 },
 218                 .bus_flags = DRM_BUS_FLAG_PIXDATA_NEGEDGE,
 219                 .ib2 = true,
 220         },
 221 };
 222
 223 static inline struct versatile_panel *
 224 to_versatile_panel(struct drm_panel *panel)
 225 {
 226         return container_of(panel, struct versatile_panel, panel);
 227 }
 228
 229 static int versatile_panel_disable(struct drm_panel *panel)
 230 {
 231         struct versatile_panel *vpanel = to_versatile_panel(panel);
 232
 233         /* If we're on an IB2 daughterboard, turn off display */
 234         if (vpanel->ib2_map) {
 235                 dev_dbg(vpanel->dev, "disable IB2 display\n");
 236                 regmap_update_bits(vpanel->ib2_map,
 237                                    IB2_CTRL,
 238                                    IB2_CTRL_LCD_MASK,
 239                                    IB2_CTRL_LCD_SD);
 240         }
 241
 242         return 0;
 243 }
 244
 245 static int versatile_panel_enable(struct drm_panel *panel)
 246 {
 247         struct versatile_panel *vpanel = to_versatile_panel(panel);
 248
 249         /* If we're on an IB2 daughterboard, turn on display */
 250         if (vpanel->ib2_map) {
 251                 dev_dbg(vpanel->dev, "enable IB2 display\n");
 252                 regmap_update_bits(vpanel->ib2_map,
 253                                    IB2_CTRL,
 254                                    IB2_CTRL_LCD_MASK,
 255                                    IB2_CTRL_LCD_BL_ON);
 256         }
 257
 258         return 0;
 259 }
 260
 261 static int versatile_panel_get_modes(struct drm_panel *panel)
 262 {
 263         struct drm_connector *connector = panel->connector;
 264         struct versatile_panel *vpanel = to_versatile_panel(panel);
 265         struct drm_display_mode *mode;
 266
 267         strncpy(connector->display_info.name, vpanel->panel_type->name,
 268                 DRM_DISPLAY_INFO_LEN);
 269         connector->display_info.width_mm = vpanel->panel_type->width_mm;
 270         connector->display_info.height_mm = vpanel->panel_type->height_mm;
 271         connector->display_info.bus_flags = vpanel->panel_type->bus_flags;
 272
 273         mode = drm_mode_duplicate(panel->drm, &vpanel->panel_type->mode);
 274         drm_mode_set_name(mode);
 275         mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
 276
 277         mode->width_mm = vpanel->panel_type->width_mm;
 278         mode->height_mm = vpanel->panel_type->height_mm;
 279         drm_mode_probed_add(connector, mode);
 280
 281         return 1;
 282 }
 283
 284 static const struct drm_panel_funcs versatile_panel_drm_funcs = {
 285         .disable = versatile_panel_disable,
 286         .enable = versatile_panel_enable,
 287         .get_modes = versatile_panel_get_modes,
 288 };
 289
 290 static int versatile_panel_probe(struct platform_device *pdev)
 291 {
 292         struct device *dev = &pdev->dev;
 293         struct versatile_panel *vpanel;
 294         struct device *parent;
 295         struct regmap *map;
 296         int ret;
 297         u32 val;
 298         int i;
 299
 300         parent = dev->parent;
 301         if (!parent) {
 302                 dev_err(dev, "no parent for versatile panel\n");
 303                 return -ENODEV;
 304         }
 305         map = syscon_node_to_regmap(parent->of_node);
 306         if (IS_ERR(map)) {
 307                 dev_err(dev, "no regmap for versatile panel parent\n");
 308                 return PTR_ERR(map);
 309         }
 310
 311         vpanel = devm_kzalloc(dev, sizeof(*vpanel), GFP_KERNEL);
 312         if (!vpanel)
 313                 return -ENOMEM;
 314
 315         ret = regmap_read(map, SYS_CLCD, &val);
 316         if (ret) {
 317                 dev_err(dev, "cannot access syscon regs\n");
 318                 return ret;
 319         }
 320
 321         val &= SYS_CLCD_CLCDID_MASK;
 322
 323         for (i = 0; i < ARRAY_SIZE(versatile_panels); i++) {
 324                 const struct versatile_panel_type *pt;
 325
 326                 pt = &versatile_panels[i];
 327                 if (pt->magic == val) {
 328                         vpanel->panel_type = pt;
 329                         break;
 330                 }
 331         }
 332
 333         /* No panel detected or VGA, let's leave this show */
 334         if (i == ARRAY_SIZE(versatile_panels)) {
 335                 dev_info(dev, "no panel detected\n");
 336                 return -ENODEV;
 337         }
 338
 339         dev_info(dev, "detected: %s\n", vpanel->panel_type->name);
 340         vpanel->dev = dev;
 341         vpanel->map = map;
 342
 343         /* Check if the panel is mounted on an IB2 daughterboard */
 344         if (vpanel->panel_type->ib2) {
 345                 vpanel->ib2_map = syscon_regmap_lookup_by_compatible(
 346                         "arm,versatile-ib2-syscon");
 347                 if (IS_ERR(vpanel->ib2_map))
 348                         vpanel->ib2_map = NULL;
 349                 else
 350                         dev_info(dev, "panel mounted on IB2 daughterboard\n");
 351         }
 352
 353         drm_panel_init(&vpanel->panel);
 354         vpanel->panel.dev = dev;
 355         vpanel->panel.funcs = &versatile_panel_drm_funcs;
 356
 357         return drm_panel_add(&vpanel->panel);
 358 }
 359
 360 static const struct of_device_id versatile_panel_match[] = {
 361         { .compatible = "arm,versatile-tft-panel", },
 362         {},
 363 };
 364 MODULE_DEVICE_TABLE(of, versatile_panel_match);
 365
 366 static struct platform_driver versatile_panel_driver = {
 367         .probe          = versatile_panel_probe,
 368         .driver         = {
 369                 .name   = "versatile-tft-panel",
 370                 .of_match_table = versatile_panel_match,
 371         },
 372 };
 373 module_platform_driver(versatile_panel_driver);
 374
 375 MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
 376 MODULE_DESCRIPTION("ARM Versatile panel driver");
 377 MODULE_LICENSE("GPL v2");