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         if (kbd_write(I8042_DATA_REG, CMD_DRAIN_OUTPUT) ||
 138             kbd_read(I8042_DATA_REG) != KBD_ACK)
 139                 goto err;
 140
 141         /* set AT translation and disable irq */
 142         config = kbd_cmd_read(CMD_RD_CONFIG);
 143         if (config == -1)
 144                 goto err;
 145
 146         /* Sometimes get a second byte */
 147         else if ((quirk & QUIRK_DUP_POR) && config == KBD_POR)
 148                 config = kbd_cmd_read(CMD_RD_CONFIG);
 149
 150         config |= CONFIG_AT_TRANS;
 151         config &= ~(CONFIG_KIRQ_EN | CONFIG_MIRQ_EN);
 152         if (kbd_cmd_write(CMD_WR_CONFIG, config))
 153                 goto err;
 154
 155         /* enable keyboard */
 156         if (kbd_write(I8042_CMD_REG, CMD_KBD_EN) ||
 157             !kbd_input_empty())
 158                 goto err;
 159
 160         return 0;
 161 err:
 162         debug("%s: Keyboard failure\n", __func__);
 163         return -1;
 164 }
 165
 166 static int kbd_controller_present(void)
 167 {
 168         return in8(I8042_STS_REG) != 0xff;
 169 }
 170
 171 /*
 172  * Implement a weak default function for boards that optionally
 173  * need to skip the i8042 initialization.
 174  *
 175  * TODO(sjg@chromium.org): Use device tree for this?
 176  */
 177 int __weak board_i8042_skip(void)
 178 {
 179         /* As default, don't skip */
 180         return 0;
 181 }
 182
 183 void i8042_flush(void)
 184 {
 185         int timeout;
 186
 187         /*
 188          * The delay is to give the keyboard controller some time
 189          * to fill the next byte.
 190          */
 191         while (1) {
 192                 timeout = 100;  /* wait for no longer than 100us */
 193                 while (timeout > 0 && !(in8(I8042_STS_REG) & STATUS_OBF)) {
 194                         udelay(1);
 195                         timeout--;
 196                 }
 197
 198                 /* Try to pull next byte if not timeout */
 199                 if (in8(I8042_STS_REG) & STATUS_OBF)
 200                         in8(I8042_DATA_REG);
 201                 else
 202                         break;
 203         }
 204 }
 205
 206 int i8042_disable(void)
 207 {
 208         if (kbd_input_empty() == 0)
 209                 return -1;
 210
 211         /* Disable keyboard */
 212         out8(I8042_CMD_REG, CMD_KBD_DIS);
 213
 214         if (kbd_input_empty() == 0)
 215                 return -1;
 216
 217         return 0;
 218 }
 219
 220 static int i8042_kbd_check(struct input_config *input)
 221 {
 222         struct i8042_kbd_priv *priv = dev_get_priv(input->dev);
 223
 224         if ((in8(I8042_STS_REG) & STATUS_OBF) == 0) {
 225                 return 0;
 226         } else {
 227                 bool release = false;
 228                 int scan_code;
 229                 int i;
 230
 231                 scan_code = in8(I8042_DATA_REG);
 232                 if (scan_code == 0xfa) {
 233                         return 0;
 234                 } else if (scan_code == 0xe0) {
 235                         priv->extended = true;
 236                         return 0;
 237                 }
 238                 if (scan_code & 0x80) {
 239                         scan_code &= 0x7f;
 240                         release = true;
 241                 }
 242                 if (priv->extended) {
 243                         priv->extended = false;
 244                         for (i = 0; ext_key_map[i]; i++) {
 245                                 if (ext_key_map[i] == scan_code) {
 246                                         scan_code = 0x60 + i;
 247                                         break;
 248                                 }
 249                         }
 250                         /* not found ? */
 251                         if (!ext_key_map[i])
 252                                 return 0;
 253                 }
 254
 255                 input_add_keycode(input, scan_code, release);
 256                 return 1;
 257         }
 258 }
 259
 260 /* i8042_kbd_init - reset keyboard and init state flags */
 261 static int i8042_start(struct udevice *dev)
 262 {
 263         struct keyboard_priv *uc_priv = dev_get_uclass_priv(dev);
 264         struct i8042_kbd_priv *priv = dev_get_priv(dev);
 265         struct input_config *input = &uc_priv->input;
 266         int keymap, try;
 267         char *penv;
 268         int ret;
 269
 270         if (!kbd_controller_present() || board_i8042_skip()) {
 271                 debug("i8042 keyboard controller is not present\n");
 272                 return -ENOENT;
 273         }
 274
 275         /* Init keyboard device (default US layout) */
 276         keymap = KBD_US;
 277         penv = env_get("keymap");
 278         if (penv != NULL) {
 279                 if (strncmp(penv, "de", 3) == 0)
 280                         keymap = KBD_GER;
 281         }
 282
 283         for (try = 0; kbd_reset(priv->quirks) != 0; try++) {
 284                 if (try >= KBD_RESET_TRIES)
 285                         return -1;
 286         }
 287
 288         ret = input_add_tables(input, keymap == KBD_GER);
 289         if (ret)
 290                 return ret;
 291
 292         i8042_kbd_update_leds(dev, NORMAL);
 293         debug("%s: started\n", __func__);
 294
 295         return 0;
 296 }
 297
 298 /**
 299  * Set up the i8042 keyboard. This is called by the stdio device handler
 300  *
 301  * We want to do this init when the keyboard is actually used rather than
 302  * at start-up, since keyboard input may not currently be selected.
 303  *
 304  * Once the keyboard starts there will be a period during which we must
 305  * wait for the keyboard to init. We do this only when a key is first
 306  * read - see kbd_wait_for_fifo_init().
 307  *
 308  * @return 0 if ok, -ve on error
 309  */
 310 static int i8042_kbd_probe(struct udevice *dev)
 311 {
 312         struct keyboard_priv *uc_priv = dev_get_uclass_priv(dev);
 313         struct i8042_kbd_priv *priv = dev_get_priv(dev);
 314         struct stdio_dev *sdev = &uc_priv->sdev;
 315         struct input_config *input = &uc_priv->input;
 316         int ret;
 317
 318         if (fdtdec_get_bool(gd->fdt_blob, dev_of_offset(dev),
 319                             "intel,duplicate-por"))
 320                 priv->quirks |= QUIRK_DUP_POR;
 321
 322         /* Register the device. i8042_start() will be called soon */
 323         input->dev = dev;
 324         input->read_keys = i8042_kbd_check;
 325         input_allow_repeats(input, true);
 326         strcpy(sdev->name, "i8042-kbd");
 327         ret = input_stdio_register(sdev);
 328         if (ret) {
 329                 debug("%s: input_stdio_register() failed\n", __func__);
 330                 return ret;
 331         }
 332         debug("%s: ready\n", __func__);
 333
 334         return 0;
 335 }
 336
 337 static const struct keyboard_ops i8042_kbd_ops = {
 338         .start  = i8042_start,
 339         .update_leds    = i8042_kbd_update_leds,
 340 };
 341
 342 static const struct udevice_id i8042_kbd_ids[] = {
 343         { .compatible = "intel,i8042-keyboard" },
 344         { }
 345 };
 346
 347 U_BOOT_DRIVER(i8042_kbd) = {
 348         .name   = "i8042_kbd",
 349         .id     = UCLASS_KEYBOARD,
 350         .of_match = i8042_kbd_ids,
 351         .probe = i8042_kbd_probe,
 352         .ops    = &i8042_kbd_ops,
 353         .priv_auto_alloc_size = sizeof(struct i8042_kbd_priv),
 354 };