drivers/input/i8042.c

   1 /*
   2  * (C) Copyright 2002 ELTEC Elektronik AG
   3  * Frank Gottschling <fgottschling@eltec.de>
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 /* i8042.c - Intel 8042 keyboard driver routines */
   9
  10 #include <common.h>
  11 #include <dm.h>
  12 #include <errno.h>
  13 #include <i8042.h>
  14 #include <input.h>
  15 #include <keyboard.h>
  16 #include <asm/io.h>
  17
  18 DECLARE_GLOBAL_DATA_PTR;
  19
  20 /* defines */
  21 #define in8(p)          inb(p)
  22 #define out8(p, v)      outb(v, p)
  23
  24 enum {
  25         QUIRK_DUP_POR   = 1 << 0,
  26 };
  27
  28 /* locals */
  29 struct i8042_kbd_priv {
  30         bool extended;  /* true if an extended keycode is expected next */
  31         int quirks;     /* quirks that we support */
  32 };
  33
  34 static unsigned char ext_key_map[] = {
  35         0x1c, /* keypad enter */
  36         0x1d, /* right control */
  37         0x35, /* keypad slash */
  38         0x37, /* print screen */
  39         0x38, /* right alt */
  40         0x46, /* break */
  41         0x47, /* editpad home */
  42         0x48, /* editpad up */
  43         0x49, /* editpad pgup */
  44         0x4b, /* editpad left */
  45         0x4d, /* editpad right */
  46         0x4f, /* editpad end */
  47         0x50, /* editpad dn */
  48         0x51, /* editpad pgdn */
  49         0x52, /* editpad ins */
  50         0x53, /* editpad del */
  51         0x00  /* map end */
  52         };
  53
  54 static int kbd_input_empty(void)
  55 {
  56         int kbd_timeout = KBD_TIMEOUT * 1000;
  57
  58         while ((in8(I8042_STS_REG) & STATUS_IBF) && kbd_timeout--)
  59                 udelay(1);
  60
  61         return kbd_timeout != -1;
  62 }
  63
  64 static int kbd_output_full(void)
  65 {
  66         int kbd_timeout = KBD_TIMEOUT * 1000;
  67
  68         while (((in8(I8042_STS_REG) & STATUS_OBF) == 0) && kbd_timeout--)
  69                 udelay(1);
  70
  71         return kbd_timeout != -1;
  72 }
  73
  74 /**
  75  * check_leds() - Check the keyboard LEDs and update them it needed
  76  *
  77  * @ret:        Value to return
  78  * @return value of @ret
  79  */
  80 static int i8042_kbd_update_leds(struct udevice *dev, int leds)
  81 {
  82         kbd_input_empty();
  83         out8(I8042_DATA_REG, CMD_SET_KBD_LED);
  84         kbd_input_empty();
  85         out8(I8042_DATA_REG, leds & 0x7);
  86
  87         return 0;
  88 }
  89
  90 static int kbd_write(int reg, int value)
  91 {
  92         if (!kbd_input_empty())
  93                 return -1;
  94         out8(reg, value);
  95
  96         return 0;
  97 }
  98
  99 static int kbd_read(int reg)
 100 {
 101         if (!kbd_output_full())
 102                 return -1;
 103
 104         return in8(reg);
 105 }
 106
 107 static int kbd_cmd_read(int cmd)
 108 {
 109         if (kbd_write(I8042_CMD_REG, cmd))
 110                 return -1;
 111
 112         return kbd_read(I8042_DATA_REG);
 113 }
 114
 115 static int kbd_cmd_write(int cmd, int data)
 116 {
 117         if (kbd_write(I8042_CMD_REG, cmd))
 118                 return -1;
 119
 120         return kbd_write(I8042_DATA_REG, data);
 121 }
 122
 123 static int kbd_reset(int quirk)
 124 {
 125         int config;
 126
 127         /* controller self test */
 128         if (kbd_cmd_read(CMD_SELF_TEST) != KBC_TEST_OK)
 129                 goto err;
 130
 131         /* keyboard reset */
 132         if (kbd_write(I8042_DATA_REG, CMD_RESET_KBD) ||
 133             kbd_read(I8042_DATA_REG) != KBD_ACK ||
 134             kbd_read(I8042_DATA_REG) != KBD_POR)
 135                 goto err;
 136
 137         /* set AT translation and disable irq */
 138         config = kbd_cmd_read(CMD_RD_CONFIG);
 139         if (config == -1)
 140                 goto err;
 141
 142         /* Sometimes get a second byte */
 143         else if ((quirk & QUIRK_DUP_POR) && config == KBD_POR)
 144                 config = kbd_cmd_read(CMD_RD_CONFIG);
 145
 146         config |= CONFIG_AT_TRANS;
 147         config &= ~(CONFIG_KIRQ_EN | CONFIG_MIRQ_EN);
 148         if (kbd_cmd_write(CMD_WR_CONFIG, config))
 149                 goto err;
 150
 151         /* enable keyboard */
 152         if (kbd_write(I8042_CMD_REG, CMD_KBD_EN) ||
 153             !kbd_input_empty())
 154                 goto err;
 155
 156         return 0;
 157 err:
 158         debug("%s: Keyboard failure\n", __func__);
 159         return -1;
 160 }
 161
 162 static int kbd_controller_present(void)
 163 {
 164         return in8(I8042_STS_REG) != 0xff;
 165 }
 166
 167 /*
 168  * Implement a weak default function for boards that optionally
 169  * need to skip the i8042 initialization.
 170  *
 171  * TODO(sjg@chromium.org): Use device tree for this?
 172  */
 173 int __weak board_i8042_skip(void)
 174 {
 175         /* As default, don't skip */
 176         return 0;
 177 }
 178
 179 void i8042_flush(void)
 180 {
 181         int timeout;
 182
 183         /*
 184          * The delay is to give the keyboard controller some time
 185          * to fill the next byte.
 186          */
 187         while (1) {
 188                 timeout = 100;  /* wait for no longer than 100us */
 189                 while (timeout > 0 && !(in8(I8042_STS_REG) & STATUS_OBF)) {
 190                         udelay(1);
 191                         timeout--;
 192                 }
 193
 194                 /* Try to pull next byte if not timeout */
 195                 if (in8(I8042_STS_REG) & STATUS_OBF)
 196                         in8(I8042_DATA_REG);
 197                 else
 198                         break;
 199         }
 200 }
 201
 202 int i8042_disable(void)
 203 {
 204         if (kbd_input_empty() == 0)
 205                 return -1;
 206
 207         /* Disable keyboard */
 208         out8(I8042_CMD_REG, CMD_KBD_DIS);
 209
 210         if (kbd_input_empty() == 0)
 211                 return -1;
 212
 213         return 0;
 214 }
 215
 216 static int i8042_kbd_check(struct input_config *input)
 217 {
 218         struct i8042_kbd_priv *priv = dev_get_priv(input->dev);
 219
 220         if ((in8(I8042_STS_REG) & STATUS_OBF) == 0) {
 221                 return 0;
 222         } else {
 223                 bool release = false;
 224                 int scan_code;
 225                 int i;
 226
 227                 scan_code = in8(I8042_DATA_REG);
 228                 if (scan_code == 0xfa) {
 229                         return 0;
 230                 } else if (scan_code == 0xe0) {
 231                         priv->extended = true;
 232                         return 0;
 233                 }
 234                 if (scan_code & 0x80) {
 235                         scan_code &= 0x7f;
 236                         release = true;
 237                 }
 238                 if (priv->extended) {
 239                         priv->extended = false;
 240                         for (i = 0; ext_key_map[i]; i++) {
 241                                 if (ext_key_map[i] == scan_code) {
 242                                         scan_code = 0x60 + i;
 243                                         break;
 244                                 }
 245                         }
 246                         /* not found ? */
 247                         if (!ext_key_map[i])
 248                                 return 0;
 249                 }
 250
 251                 input_add_keycode(input, scan_code, release);
 252                 return 1;
 253         }
 254 }
 255
 256 /* i8042_kbd_init - reset keyboard and init state flags */
 257 static int i8042_start(struct udevice *dev)
 258 {
 259         struct keyboard_priv *uc_priv = dev_get_uclass_priv(dev);
 260         struct i8042_kbd_priv *priv = dev_get_priv(dev);
 261         struct input_config *input = &uc_priv->input;
 262         int keymap, try;
 263         char *penv;
 264         int ret;
 265
 266         if (!kbd_controller_present() || board_i8042_skip()) {
 267                 debug("i8042 keyboard controller is not present\n");
 268                 return -ENOENT;
 269         }
 270
 271         /* Init keyboard device (default US layout) */
 272         keymap = KBD_US;
 273         penv = getenv("keymap");
 274         if (penv != NULL) {
 275                 if (strncmp(penv, "de", 3) == 0)
 276                         keymap = KBD_GER;
 277         }
 278
 279         for (try = 0; kbd_reset(priv->quirks) != 0; try++) {
 280                 if (try >= KBD_RESET_TRIES)
 281                         return -1;
 282         }
 283
 284         ret = input_add_tables(input, keymap == KBD_GER);
 285         if (ret)
 286                 return ret;
 287
 288         i8042_kbd_update_leds(dev, NORMAL);
 289         debug("%s: started\n", __func__);
 290
 291         return 0;
 292 }
 293
 294 /**
 295  * Set up the i8042 keyboard. This is called by the stdio device handler
 296  *
 297  * We want to do this init when the keyboard is actually used rather than
 298  * at start-up, since keyboard input may not currently be selected.
 299  *
 300  * Once the keyboard starts there will be a period during which we must
 301  * wait for the keyboard to init. We do this only when a key is first
 302  * read - see kbd_wait_for_fifo_init().
 303  *
 304  * @return 0 if ok, -ve on error
 305  */
 306 static int i8042_kbd_probe(struct udevice *dev)
 307 {
 308         struct keyboard_priv *uc_priv = dev_get_uclass_priv(dev);
 309         struct i8042_kbd_priv *priv = dev_get_priv(dev);
 310         struct stdio_dev *sdev = &uc_priv->sdev;
 311         struct input_config *input = &uc_priv->input;
 312         int ret;
 313
 314         if (fdtdec_get_bool(gd->fdt_blob, dev->of_offset,
 315                             "intel,duplicate-por"))
 316                 priv->quirks |= QUIRK_DUP_POR;
 317
 318         /* Register the device. i8042_start() will be called soon */
 319         input->dev = dev;
 320         input->read_keys = i8042_kbd_check;
 321         input_allow_repeats(input, true);
 322         strcpy(sdev->name, "i8042-kbd");
 323         ret = input_stdio_register(sdev);
 324         if (ret) {
 325                 debug("%s: input_stdio_register() failed\n", __func__);
 326                 return ret;
 327         }
 328         debug("%s: ready\n", __func__);
 329
 330         return 0;
 331 }
 332
 333 static const struct keyboard_ops i8042_kbd_ops = {
 334         .start  = i8042_start,
 335         .update_leds    = i8042_kbd_update_leds,
 336 };
 337
 338 static const struct udevice_id i8042_kbd_ids[] = {
 339         { .compatible = "intel,i8042-keyboard" },
 340         { }
 341 };
 342
 343 U_BOOT_DRIVER(i8042_kbd) = {
 344         .name   = "i8042_kbd",
 345         .id     = UCLASS_KEYBOARD,
 346         .of_match = i8042_kbd_ids,
 347         .probe = i8042_kbd_probe,
 348         .ops    = &i8042_kbd_ops,
 349         .priv_auto_alloc_size = sizeof(struct i8042_kbd_priv),
 350 };