drivers/auxdisplay/ht16k33.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * HT16K33 driver
   4  *
   5  * Author: Robin van der Gracht <[email protected]>
   6  *
   7  * Copyright: (C) 2016 Protonic Holland.
   8  * Copyright (C) 2021 Glider bv
   9  */
  10
  11 #include <linux/kernel.h>
  12 #include <linux/module.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/i2c.h>
  15 #include <linux/property.h>
  16 #include <linux/fb.h>
  17 #include <linux/backlight.h>
  18 #include <linux/container_of.h>
  19 #include <linux/input.h>
  20 #include <linux/input/matrix_keypad.h>
  21 #include <linux/leds.h>
  22 #include <linux/workqueue.h>
  23 #include <linux/mm.h>
  24
  25 #include <linux/map_to_7segment.h>
  26 #include <linux/map_to_14segment.h>
  27
  28 #include <asm/unaligned.h>
  29
  30 #include "line-display.h"
  31
  32 /* Registers */
  33 #define REG_SYSTEM_SETUP                0x20
  34 #define REG_SYSTEM_SETUP_OSC_ON         BIT(0)
  35
  36 #define REG_DISPLAY_SETUP               0x80
  37 #define REG_DISPLAY_SETUP_ON            BIT(0)
  38 #define REG_DISPLAY_SETUP_BLINK_OFF     (0 << 1)
  39 #define REG_DISPLAY_SETUP_BLINK_2HZ     (1 << 1)
  40 #define REG_DISPLAY_SETUP_BLINK_1HZ     (2 << 1)
  41 #define REG_DISPLAY_SETUP_BLINK_0HZ5    (3 << 1)
  42
  43 #define REG_ROWINT_SET                  0xA0
  44 #define REG_ROWINT_SET_INT_EN           BIT(0)
  45 #define REG_ROWINT_SET_INT_ACT_HIGH     BIT(1)
  46
  47 #define REG_BRIGHTNESS                  0xE0
  48
  49 /* Defines */
  50 #define DRIVER_NAME                     "ht16k33"
  51
  52 #define MIN_BRIGHTNESS                  0x1
  53 #define MAX_BRIGHTNESS                  0x10
  54
  55 #define HT16K33_MATRIX_LED_MAX_COLS     8
  56 #define HT16K33_MATRIX_LED_MAX_ROWS     16
  57 #define HT16K33_MATRIX_KEYPAD_MAX_COLS  3
  58 #define HT16K33_MATRIX_KEYPAD_MAX_ROWS  12
  59
  60 #define BYTES_PER_ROW           (HT16K33_MATRIX_LED_MAX_ROWS / 8)
  61 #define HT16K33_FB_SIZE         (HT16K33_MATRIX_LED_MAX_COLS * BYTES_PER_ROW)
  62
  63 enum display_type {
  64         DISP_MATRIX = 0,
  65         DISP_QUAD_7SEG,
  66         DISP_QUAD_14SEG,
  67 };
  68
  69 struct ht16k33_keypad {
  70         struct i2c_client *client;
  71         struct input_dev *dev;
  72         uint32_t cols;
  73         uint32_t rows;
  74         uint32_t row_shift;
  75         uint32_t debounce_ms;
  76         uint16_t last_key_state[HT16K33_MATRIX_KEYPAD_MAX_COLS];
  77
  78         wait_queue_head_t wait;
  79         bool stopped;
  80 };
  81
  82 struct ht16k33_fbdev {
  83         struct fb_info *info;
  84         uint32_t refresh_rate;
  85         uint8_t *buffer;
  86         uint8_t *cache;
  87 };
  88
  89 struct ht16k33_priv {
  90         struct i2c_client *client;
  91         struct delayed_work work;
  92         struct led_classdev led;
  93         struct ht16k33_keypad keypad;
  94         union {
  95                 struct ht16k33_fbdev fbdev;
  96                 struct linedisp linedisp;
  97         };
  98         enum display_type type;
  99         uint8_t blink;
 100 };
 101
 102 #define ht16k33_work_to_priv(p)                         \
 103         container_of(p, struct ht16k33_priv, work.work)
 104
 105 #define ht16k33_led_to_priv(p)                          \
 106         container_of(p, struct ht16k33_priv, led)
 107
 108 #define ht16k33_linedisp_to_priv(p)                     \
 109         container_of(p, struct ht16k33_priv, linedisp)
 110
 111 static const struct fb_fix_screeninfo ht16k33_fb_fix = {
 112         .id             = DRIVER_NAME,
 113         .type           = FB_TYPE_PACKED_PIXELS,
 114         .visual         = FB_VISUAL_MONO10,
 115         .xpanstep       = 0,
 116         .ypanstep       = 0,
 117         .ywrapstep      = 0,
 118         .line_length    = HT16K33_MATRIX_LED_MAX_ROWS,
 119         .accel          = FB_ACCEL_NONE,
 120 };
 121
 122 static const struct fb_var_screeninfo ht16k33_fb_var = {
 123         .xres = HT16K33_MATRIX_LED_MAX_ROWS,
 124         .yres = HT16K33_MATRIX_LED_MAX_COLS,
 125         .xres_virtual = HT16K33_MATRIX_LED_MAX_ROWS,
 126         .yres_virtual = HT16K33_MATRIX_LED_MAX_COLS,
 127         .bits_per_pixel = 1,
 128         .red = { 0, 1, 0 },
 129         .green = { 0, 1, 0 },
 130         .blue = { 0, 1, 0 },
 131         .left_margin = 0,
 132         .right_margin = 0,
 133         .upper_margin = 0,
 134         .lower_margin = 0,
 135         .vmode = FB_VMODE_NONINTERLACED,
 136 };
 137
 138 static int ht16k33_display_on(struct ht16k33_priv *priv)
 139 {
 140         uint8_t data = REG_DISPLAY_SETUP | REG_DISPLAY_SETUP_ON | priv->blink;
 141
 142         return i2c_smbus_write_byte(priv->client, data);
 143 }
 144
 145 static int ht16k33_display_off(struct ht16k33_priv *priv)
 146 {
 147         return i2c_smbus_write_byte(priv->client, REG_DISPLAY_SETUP);
 148 }
 149
 150 static int ht16k33_brightness_set(struct ht16k33_priv *priv,
 151                                   unsigned int brightness)
 152 {
 153         int err;
 154
 155         if (brightness == 0) {
 156                 priv->blink = REG_DISPLAY_SETUP_BLINK_OFF;
 157                 return ht16k33_display_off(priv);
 158         }
 159
 160         err = ht16k33_display_on(priv);
 161         if (err)
 162                 return err;
 163
 164         return i2c_smbus_write_byte(priv->client,
 165                                     REG_BRIGHTNESS | (brightness - 1));
 166 }
 167
 168 static int ht16k33_brightness_set_blocking(struct led_classdev *led_cdev,
 169                                            enum led_brightness brightness)
 170 {
 171         struct ht16k33_priv *priv = ht16k33_led_to_priv(led_cdev);
 172
 173         return ht16k33_brightness_set(priv, brightness);
 174 }
 175
 176 static int ht16k33_blink_set(struct led_classdev *led_cdev,
 177                              unsigned long *delay_on, unsigned long *delay_off)
 178 {
 179         struct ht16k33_priv *priv = ht16k33_led_to_priv(led_cdev);
 180         unsigned int delay;
 181         uint8_t blink;
 182         int err;
 183
 184         if (!*delay_on && !*delay_off) {
 185                 blink = REG_DISPLAY_SETUP_BLINK_1HZ;
 186                 delay = 1000;
 187         } else if (*delay_on <= 750) {
 188                 blink = REG_DISPLAY_SETUP_BLINK_2HZ;
 189                 delay = 500;
 190         } else if (*delay_on <= 1500) {
 191                 blink = REG_DISPLAY_SETUP_BLINK_1HZ;
 192                 delay = 1000;
 193         } else {
 194                 blink = REG_DISPLAY_SETUP_BLINK_0HZ5;
 195                 delay = 2000;
 196         }
 197
 198         err = i2c_smbus_write_byte(priv->client,
 199                                    REG_DISPLAY_SETUP | REG_DISPLAY_SETUP_ON |
 200                                    blink);
 201         if (err)
 202                 return err;
 203
 204         priv->blink = blink;
 205         *delay_on = *delay_off = delay;
 206         return 0;
 207 }
 208
 209 static void ht16k33_fb_queue(struct ht16k33_priv *priv)
 210 {
 211         struct ht16k33_fbdev *fbdev = &priv->fbdev;
 212
 213         schedule_delayed_work(&priv->work, HZ / fbdev->refresh_rate);
 214 }
 215
 216 /*
 217  * This gets the fb data from cache and copies it to ht16k33 display RAM
 218  */
 219 static void ht16k33_fb_update(struct work_struct *work)
 220 {
 221         struct ht16k33_priv *priv = ht16k33_work_to_priv(work);
 222         struct ht16k33_fbdev *fbdev = &priv->fbdev;
 223
 224         uint8_t *p1, *p2;
 225         int len, pos = 0, first = -1;
 226
 227         p1 = fbdev->cache;
 228         p2 = fbdev->buffer;
 229
 230         /* Search for the first byte with changes */
 231         while (pos < HT16K33_FB_SIZE && first < 0) {
 232                 if (*(p1++) - *(p2++))
 233                         first = pos;
 234                 pos++;
 235         }
 236
 237         /* No changes found */
 238         if (first < 0)
 239                 goto requeue;
 240
 241         len = HT16K33_FB_SIZE - first;
 242         p1 = fbdev->cache + HT16K33_FB_SIZE - 1;
 243         p2 = fbdev->buffer + HT16K33_FB_SIZE - 1;
 244
 245         /* Determine i2c transfer length */
 246         while (len > 1) {
 247                 if (*(p1--) - *(p2--))
 248                         break;
 249                 len--;
 250         }
 251
 252         p1 = fbdev->cache + first;
 253         p2 = fbdev->buffer + first;
 254         if (!i2c_smbus_write_i2c_block_data(priv->client, first, len, p2))
 255                 memcpy(p1, p2, len);
 256 requeue:
 257         ht16k33_fb_queue(priv);
 258 }
 259
 260 static int ht16k33_initialize(struct ht16k33_priv *priv)
 261 {
 262         uint8_t data[HT16K33_FB_SIZE];
 263         uint8_t byte;
 264         int err;
 265
 266         /* Clear RAM (8 * 16 bits) */
 267         memset(data, 0, sizeof(data));
 268         err = i2c_smbus_write_block_data(priv->client, 0, sizeof(data), data);
 269         if (err)
 270                 return err;
 271
 272         /* Turn on internal oscillator */
 273         byte = REG_SYSTEM_SETUP_OSC_ON | REG_SYSTEM_SETUP;
 274         err = i2c_smbus_write_byte(priv->client, byte);
 275         if (err)
 276                 return err;
 277
 278         /* Configure INT pin */
 279         byte = REG_ROWINT_SET | REG_ROWINT_SET_INT_ACT_HIGH;
 280         if (priv->client->irq > 0)
 281                 byte |= REG_ROWINT_SET_INT_EN;
 282         return i2c_smbus_write_byte(priv->client, byte);
 283 }
 284
 285 static int ht16k33_bl_update_status(struct backlight_device *bl)
 286 {
 287         const int brightness = backlight_get_brightness(bl);
 288         struct ht16k33_priv *priv = bl_get_data(bl);
 289
 290         return ht16k33_brightness_set(priv, brightness);
 291 }
 292
 293 static const struct backlight_ops ht16k33_bl_ops = {
 294         .update_status  = ht16k33_bl_update_status,
 295 };
 296
 297 /*
 298  * Blank events will be passed to the actual device handling the backlight when
 299  * we return zero here.
 300  */
 301 static int ht16k33_blank(int blank, struct fb_info *info)
 302 {
 303         return 0;
 304 }
 305
 306 static int ht16k33_mmap(struct fb_info *info, struct vm_area_struct *vma)
 307 {
 308         struct ht16k33_priv *priv = info->par;
 309         struct page *pages = virt_to_page(priv->fbdev.buffer);
 310
 311         vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
 312
 313         return vm_map_pages_zero(vma, &pages, 1);
 314 }
 315
 316 static const struct fb_ops ht16k33_fb_ops = {
 317         .owner = THIS_MODULE,
 318         __FB_DEFAULT_SYSMEM_OPS_RDWR,
 319         .fb_blank = ht16k33_blank,
 320         __FB_DEFAULT_SYSMEM_OPS_DRAW,
 321         .fb_mmap = ht16k33_mmap,
 322 };
 323
 324 /*
 325  * This gets the keys from keypad and reports it to input subsystem.
 326  * Returns true if a key is pressed.
 327  */
 328 static bool ht16k33_keypad_scan(struct ht16k33_keypad *keypad)
 329 {
 330         const unsigned short *keycodes = keypad->dev->keycode;
 331         u16 new_state[HT16K33_MATRIX_KEYPAD_MAX_COLS];
 332         __le16 data[HT16K33_MATRIX_KEYPAD_MAX_COLS];
 333         unsigned long bits_changed;
 334         int row, col, code;
 335         int rc;
 336         bool pressed = false;
 337
 338         rc = i2c_smbus_read_i2c_block_data(keypad->client, 0x40,
 339                                            sizeof(data), (u8 *)data);
 340         if (rc != sizeof(data)) {
 341                 dev_err(&keypad->client->dev,
 342                         "Failed to read key data, rc=%d\n", rc);
 343                 return false;
 344         }
 345
 346         for (col = 0; col < keypad->cols; col++) {
 347                 new_state[col] = le16_to_cpu(data[col]);
 348                 if (new_state[col])
 349                         pressed = true;
 350                 bits_changed = keypad->last_key_state[col] ^ new_state[col];
 351
 352                 for_each_set_bit(row, &bits_changed, BITS_PER_LONG) {
 353                         code = MATRIX_SCAN_CODE(row, col, keypad->row_shift);
 354                         input_event(keypad->dev, EV_MSC, MSC_SCAN, code);
 355                         input_report_key(keypad->dev, keycodes[code],
 356                                          new_state[col] & BIT(row));
 357                 }
 358         }
 359         input_sync(keypad->dev);
 360         memcpy(keypad->last_key_state, new_state, sizeof(u16) * keypad->cols);
 361
 362         return pressed;
 363 }
 364
 365 static irqreturn_t ht16k33_keypad_irq_thread(int irq, void *dev)
 366 {
 367         struct ht16k33_keypad *keypad = dev;
 368
 369         do {
 370                 wait_event_timeout(keypad->wait, keypad->stopped,
 371                                     msecs_to_jiffies(keypad->debounce_ms));
 372                 if (keypad->stopped)
 373                         break;
 374         } while (ht16k33_keypad_scan(keypad));
 375
 376         return IRQ_HANDLED;
 377 }
 378
 379 static int ht16k33_keypad_start(struct input_dev *dev)
 380 {
 381         struct ht16k33_keypad *keypad = input_get_drvdata(dev);
 382
 383         keypad->stopped = false;
 384         mb();
 385         enable_irq(keypad->client->irq);
 386
 387         return 0;
 388 }
 389
 390 static void ht16k33_keypad_stop(struct input_dev *dev)
 391 {
 392         struct ht16k33_keypad *keypad = input_get_drvdata(dev);
 393
 394         keypad->stopped = true;
 395         mb();
 396         wake_up(&keypad->wait);
 397         disable_irq(keypad->client->irq);
 398 }
 399
 400 static void ht16k33_seg7_update(struct work_struct *work)
 401 {
 402         struct ht16k33_priv *priv = ht16k33_work_to_priv(work);
 403         struct linedisp_map *map = priv->linedisp.map;
 404         char *s = priv->linedisp.buf;
 405         uint8_t buf[9];
 406
 407         buf[0] = map_to_seg7(&map->map.seg7, *s++);
 408         buf[1] = 0;
 409         buf[2] = map_to_seg7(&map->map.seg7, *s++);
 410         buf[3] = 0;
 411         buf[4] = 0;
 412         buf[5] = 0;
 413         buf[6] = map_to_seg7(&map->map.seg7, *s++);
 414         buf[7] = 0;
 415         buf[8] = map_to_seg7(&map->map.seg7, *s++);
 416
 417         i2c_smbus_write_i2c_block_data(priv->client, 0, ARRAY_SIZE(buf), buf);
 418 }
 419
 420 static void ht16k33_seg14_update(struct work_struct *work)
 421 {
 422         struct ht16k33_priv *priv = ht16k33_work_to_priv(work);
 423         struct linedisp_map *map = priv->linedisp.map;
 424         char *s = priv->linedisp.buf;
 425         uint8_t buf[8];
 426
 427         put_unaligned_le16(map_to_seg14(&map->map.seg14, *s++), buf + 0);
 428         put_unaligned_le16(map_to_seg14(&map->map.seg14, *s++), buf + 2);
 429         put_unaligned_le16(map_to_seg14(&map->map.seg14, *s++), buf + 4);
 430         put_unaligned_le16(map_to_seg14(&map->map.seg14, *s++), buf + 6);
 431
 432         i2c_smbus_write_i2c_block_data(priv->client, 0, ARRAY_SIZE(buf), buf);
 433 }
 434
 435 static int ht16k33_linedisp_get_map_type(struct linedisp *linedisp)
 436 {
 437         struct ht16k33_priv *priv = ht16k33_linedisp_to_priv(linedisp);
 438
 439         switch (priv->type) {
 440         case DISP_QUAD_7SEG:
 441                 INIT_DELAYED_WORK(&priv->work, ht16k33_seg7_update);
 442                 return LINEDISP_MAP_SEG7;
 443
 444         case DISP_QUAD_14SEG:
 445                 INIT_DELAYED_WORK(&priv->work, ht16k33_seg14_update);
 446                 return LINEDISP_MAP_SEG14;
 447
 448         default:
 449                 return -EINVAL;
 450         }
 451 }
 452
 453 static void ht16k33_linedisp_update(struct linedisp *linedisp)
 454 {
 455         struct ht16k33_priv *priv = ht16k33_linedisp_to_priv(linedisp);
 456
 457         schedule_delayed_work(&priv->work, 0);
 458 }
 459
 460 static const struct linedisp_ops ht16k33_linedisp_ops = {
 461         .get_map_type = ht16k33_linedisp_get_map_type,
 462         .update = ht16k33_linedisp_update,
 463 };
 464
 465 static int ht16k33_led_probe(struct device *dev, struct led_classdev *led,
 466                              unsigned int brightness)
 467 {
 468         struct led_init_data init_data = {};
 469         int err;
 470
 471         /* The LED is optional */
 472         init_data.fwnode = device_get_named_child_node(dev, "led");
 473         if (!init_data.fwnode)
 474                 return 0;
 475
 476         init_data.devicename = "auxdisplay";
 477         init_data.devname_mandatory = true;
 478
 479         led->brightness_set_blocking = ht16k33_brightness_set_blocking;
 480         led->blink_set = ht16k33_blink_set;
 481         led->flags = LED_CORE_SUSPENDRESUME;
 482         led->brightness = brightness;
 483         led->max_brightness = MAX_BRIGHTNESS;
 484
 485         err = devm_led_classdev_register_ext(dev, led, &init_data);
 486         fwnode_handle_put(init_data.fwnode);
 487         if (err)
 488                 dev_err(dev, "Failed to register LED\n");
 489
 490         return err;
 491 }
 492
 493 static int ht16k33_keypad_probe(struct i2c_client *client,
 494                                 struct ht16k33_keypad *keypad)
 495 {
 496         struct device *dev = &client->dev;
 497         u32 rows = HT16K33_MATRIX_KEYPAD_MAX_ROWS;
 498         u32 cols = HT16K33_MATRIX_KEYPAD_MAX_COLS;
 499         int err;
 500
 501         keypad->client = client;
 502         init_waitqueue_head(&keypad->wait);
 503
 504         keypad->dev = devm_input_allocate_device(dev);
 505         if (!keypad->dev)
 506                 return -ENOMEM;
 507
 508         input_set_drvdata(keypad->dev, keypad);
 509
 510         keypad->dev->name = DRIVER_NAME"-keypad";
 511         keypad->dev->id.bustype = BUS_I2C;
 512         keypad->dev->open = ht16k33_keypad_start;
 513         keypad->dev->close = ht16k33_keypad_stop;
 514
 515         if (!device_property_read_bool(dev, "linux,no-autorepeat"))
 516                 __set_bit(EV_REP, keypad->dev->evbit);
 517
 518         err = device_property_read_u32(dev, "debounce-delay-ms",
 519                                        &keypad->debounce_ms);
 520         if (err) {
 521                 dev_err(dev, "key debounce delay not specified\n");
 522                 return err;
 523         }
 524
 525         err = matrix_keypad_parse_properties(dev, &rows, &cols);
 526         if (err)
 527                 return err;
 528         if (rows > HT16K33_MATRIX_KEYPAD_MAX_ROWS ||
 529             cols > HT16K33_MATRIX_KEYPAD_MAX_COLS) {
 530                 dev_err(dev, "%u rows or %u cols out of range in DT\n", rows,
 531                         cols);
 532                 return -ERANGE;
 533         }
 534
 535         keypad->rows = rows;
 536         keypad->cols = cols;
 537         keypad->row_shift = get_count_order(cols);
 538
 539         err = matrix_keypad_build_keymap(NULL, NULL, rows, cols, NULL,
 540                                          keypad->dev);
 541         if (err) {
 542                 dev_err(dev, "failed to build keymap\n");
 543                 return err;
 544         }
 545
 546         err = devm_request_threaded_irq(dev, client->irq, NULL,
 547                                         ht16k33_keypad_irq_thread,
 548                                         IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
 549                                         DRIVER_NAME, keypad);
 550         if (err) {
 551                 dev_err(dev, "irq request failed %d, error %d\n", client->irq,
 552                         err);
 553                 return err;
 554         }
 555
 556         ht16k33_keypad_stop(keypad->dev);
 557
 558         return input_register_device(keypad->dev);
 559 }
 560
 561 static int ht16k33_fbdev_probe(struct device *dev, struct ht16k33_priv *priv,
 562                                uint32_t brightness)
 563 {
 564         struct ht16k33_fbdev *fbdev = &priv->fbdev;
 565         struct backlight_device *bl = NULL;
 566         int err;
 567
 568         if (priv->led.dev) {
 569                 err = ht16k33_brightness_set(priv, brightness);
 570                 if (err)
 571                         return err;
 572         } else {
 573                 /* backwards compatibility with DT lacking an led subnode */
 574                 struct backlight_properties bl_props;
 575
 576                 memset(&bl_props, 0, sizeof(struct backlight_properties));
 577                 bl_props.type = BACKLIGHT_RAW;
 578                 bl_props.max_brightness = MAX_BRIGHTNESS;
 579
 580                 bl = devm_backlight_device_register(dev, DRIVER_NAME"-bl", dev,
 581                                                     priv, &ht16k33_bl_ops,
 582                                                     &bl_props);
 583                 if (IS_ERR(bl)) {
 584                         dev_err(dev, "failed to register backlight\n");
 585                         return PTR_ERR(bl);
 586                 }
 587
 588                 bl->props.brightness = brightness;
 589                 ht16k33_bl_update_status(bl);
 590         }
 591
 592         /* Framebuffer (2 bytes per column) */
 593         BUILD_BUG_ON(PAGE_SIZE < HT16K33_FB_SIZE);
 594         fbdev->buffer = (unsigned char *) get_zeroed_page(GFP_KERNEL);
 595         if (!fbdev->buffer)
 596                 return -ENOMEM;
 597
 598         fbdev->cache = devm_kmalloc(dev, HT16K33_FB_SIZE, GFP_KERNEL);
 599         if (!fbdev->cache) {
 600                 err = -ENOMEM;
 601                 goto err_fbdev_buffer;
 602         }
 603
 604         fbdev->info = framebuffer_alloc(0, dev);
 605         if (!fbdev->info) {
 606                 err = -ENOMEM;
 607                 goto err_fbdev_buffer;
 608         }
 609
 610         err = device_property_read_u32(dev, "refresh-rate-hz",
 611                                        &fbdev->refresh_rate);
 612         if (err) {
 613                 dev_err(dev, "refresh rate not specified\n");
 614                 goto err_fbdev_info;
 615         }
 616         fb_bl_default_curve(fbdev->info, 0, MIN_BRIGHTNESS, MAX_BRIGHTNESS);
 617
 618         INIT_DELAYED_WORK(&priv->work, ht16k33_fb_update);
 619         fbdev->info->fbops = &ht16k33_fb_ops;
 620         fbdev->info->flags |= FBINFO_VIRTFB;
 621         fbdev->info->screen_buffer = fbdev->buffer;
 622         fbdev->info->screen_size = HT16K33_FB_SIZE;
 623         fbdev->info->fix = ht16k33_fb_fix;
 624         fbdev->info->var = ht16k33_fb_var;
 625         fbdev->info->bl_dev = bl;
 626         fbdev->info->pseudo_palette = NULL;
 627         fbdev->info->par = priv;
 628
 629         err = register_framebuffer(fbdev->info);
 630         if (err)
 631                 goto err_fbdev_info;
 632
 633         ht16k33_fb_queue(priv);
 634         return 0;
 635
 636 err_fbdev_info:
 637         framebuffer_release(fbdev->info);
 638 err_fbdev_buffer:
 639         free_page((unsigned long) fbdev->buffer);
 640
 641         return err;
 642 }
 643
 644 static int ht16k33_seg_probe(struct device *dev, struct ht16k33_priv *priv,
 645                              uint32_t brightness)
 646 {
 647         struct linedisp *linedisp = &priv->linedisp;
 648         int err;
 649
 650         err = ht16k33_brightness_set(priv, brightness);
 651         if (err)
 652                 return err;
 653
 654         return linedisp_register(linedisp, dev, 4, &ht16k33_linedisp_ops);
 655 }
 656
 657 static int ht16k33_probe(struct i2c_client *client)
 658 {
 659         struct device *dev = &client->dev;
 660         const struct of_device_id *id;
 661         struct ht16k33_priv *priv;
 662         uint32_t dft_brightness;
 663         int err;
 664
 665         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
 666                 dev_err(dev, "i2c_check_functionality error\n");
 667                 return -EIO;
 668         }
 669
 670         priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 671         if (!priv)
 672                 return -ENOMEM;
 673
 674         priv->client = client;
 675         id = i2c_of_match_device(dev->driver->of_match_table, client);
 676         if (id)
 677                 priv->type = (uintptr_t)id->data;
 678         i2c_set_clientdata(client, priv);
 679
 680         err = ht16k33_initialize(priv);
 681         if (err)
 682                 return err;
 683
 684         err = device_property_read_u32(dev, "default-brightness-level",
 685                                        &dft_brightness);
 686         if (err) {
 687                 dft_brightness = MAX_BRIGHTNESS;
 688         } else if (dft_brightness > MAX_BRIGHTNESS) {
 689                 dev_warn(dev,
 690                          "invalid default brightness level: %u, using %u\n",
 691                          dft_brightness, MAX_BRIGHTNESS);
 692                 dft_brightness = MAX_BRIGHTNESS;
 693         }
 694
 695         /* LED */
 696         err = ht16k33_led_probe(dev, &priv->led, dft_brightness);
 697         if (err)
 698                 return err;
 699
 700         /* Keypad */
 701         if (client->irq > 0) {
 702                 err = ht16k33_keypad_probe(client, &priv->keypad);
 703                 if (err)
 704                         return err;
 705         }
 706
 707         switch (priv->type) {
 708         case DISP_MATRIX:
 709                 /* Frame Buffer Display */
 710                 err = ht16k33_fbdev_probe(dev, priv, dft_brightness);
 711                 break;
 712
 713         case DISP_QUAD_7SEG:
 714         case DISP_QUAD_14SEG:
 715                 /* Segment Display */
 716                 err = ht16k33_seg_probe(dev, priv, dft_brightness);
 717                 break;
 718
 719         default:
 720                 return -EINVAL;
 721         }
 722         return err;
 723 }
 724
 725 static void ht16k33_remove(struct i2c_client *client)
 726 {
 727         struct ht16k33_priv *priv = i2c_get_clientdata(client);
 728         struct ht16k33_fbdev *fbdev = &priv->fbdev;
 729
 730         cancel_delayed_work_sync(&priv->work);
 731
 732         switch (priv->type) {
 733         case DISP_MATRIX:
 734                 unregister_framebuffer(fbdev->info);
 735                 framebuffer_release(fbdev->info);
 736                 free_page((unsigned long)fbdev->buffer);
 737                 break;
 738
 739         case DISP_QUAD_7SEG:
 740         case DISP_QUAD_14SEG:
 741                 linedisp_unregister(&priv->linedisp);
 742                 break;
 743
 744         default:
 745                 break;
 746         }
 747 }
 748
 749 static const struct i2c_device_id ht16k33_i2c_match[] = {
 750         { "ht16k33", 0 },
 751         { }
 752 };
 753 MODULE_DEVICE_TABLE(i2c, ht16k33_i2c_match);
 754
 755 static const struct of_device_id ht16k33_of_match[] = {
 756         {
 757                 /* 0.56" 4-Digit 7-Segment FeatherWing Display (Red) */
 758                 .compatible = "adafruit,3108", .data = (void *)DISP_QUAD_7SEG,
 759         }, {
 760                 /* 0.54" Quad Alphanumeric FeatherWing Display (Red) */
 761                 .compatible = "adafruit,3130", .data = (void *)DISP_QUAD_14SEG,
 762         }, {
 763                 /* Generic, assumed Dot-Matrix Display */
 764                 .compatible = "holtek,ht16k33", .data = (void *)DISP_MATRIX,
 765         },
 766         { }
 767 };
 768 MODULE_DEVICE_TABLE(of, ht16k33_of_match);
 769
 770 static struct i2c_driver ht16k33_driver = {
 771         .probe          = ht16k33_probe,
 772         .remove         = ht16k33_remove,
 773         .driver         = {
 774                 .name           = DRIVER_NAME,
 775                 .of_match_table = ht16k33_of_match,
 776         },
 777         .id_table = ht16k33_i2c_match,
 778 };
 779 module_i2c_driver(ht16k33_driver);
 780
 781 MODULE_DESCRIPTION("Holtek HT16K33 driver");
 782 MODULE_LICENSE("GPL");
 783 MODULE_IMPORT_NS(LINEDISP);
 784 MODULE_AUTHOR("Robin van der Gracht <[email protected]>");