2 * (C) Copyright 2002 ELTEC Elektronik AG
3 * Frank Gottschling <fgottschling@eltec.de>
5 * SPDX-License-Identifier: GPL-2.0+
8 /* i8042.c - Intel 8042 keyboard driver routines */
18 DECLARE_GLOBAL_DATA_PTR;
22 #define out8(p, v) outb(v, p)
25 QUIRK_DUP_POR = 1 << 0,
29 struct i8042_kbd_priv {
30 bool extended; /* true if an extended keycode is expected next */
31 int quirks; /* quirks that we support */
34 static unsigned char ext_key_map[] = {
35 0x1c, /* keypad enter */
36 0x1d, /* right control */
37 0x35, /* keypad slash */
38 0x37, /* print screen */
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 */
54 static int kbd_input_empty(void)
56 int kbd_timeout = KBD_TIMEOUT * 1000;
58 while ((in8(I8042_STS_REG) & STATUS_IBF) && kbd_timeout--)
61 return kbd_timeout != -1;
64 static int kbd_output_full(void)
66 int kbd_timeout = KBD_TIMEOUT * 1000;
68 while (((in8(I8042_STS_REG) & STATUS_OBF) == 0) && kbd_timeout--)
71 return kbd_timeout != -1;
75 * check_leds() - Check the keyboard LEDs and update them it needed
77 * @ret: Value to return
78 * @return value of @ret
80 static int i8042_kbd_update_leds(struct udevice *dev, int leds)
83 out8(I8042_DATA_REG, CMD_SET_KBD_LED);
85 out8(I8042_DATA_REG, leds & 0x7);
90 static int kbd_write(int reg, int value)
92 if (!kbd_input_empty())
99 static int kbd_read(int reg)
101 if (!kbd_output_full())
107 static int kbd_cmd_read(int cmd)
109 if (kbd_write(I8042_CMD_REG, cmd))
112 return kbd_read(I8042_DATA_REG);
115 static int kbd_cmd_write(int cmd, int data)
117 if (kbd_write(I8042_CMD_REG, cmd))
120 return kbd_write(I8042_DATA_REG, data);
123 static int kbd_reset(int quirk)
127 /* controller self test */
128 if (kbd_cmd_read(CMD_SELF_TEST) != KBC_TEST_OK)
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)
137 /* set AT translation and disable irq */
138 config = kbd_cmd_read(CMD_RD_CONFIG);
142 /* Sometimes get a second byte */
143 else if ((quirk & QUIRK_DUP_POR) && config == KBD_POR)
144 config = kbd_cmd_read(CMD_RD_CONFIG);
146 config |= CONFIG_AT_TRANS;
147 config &= ~(CONFIG_KIRQ_EN | CONFIG_MIRQ_EN);
148 if (kbd_cmd_write(CMD_WR_CONFIG, config))
151 /* enable keyboard */
152 if (kbd_write(I8042_CMD_REG, CMD_KBD_EN) ||
158 debug("%s: Keyboard failure\n", __func__);
162 static int kbd_controller_present(void)
164 return in8(I8042_STS_REG) != 0xff;
168 * Implement a weak default function for boards that optionally
169 * need to skip the i8042 initialization.
171 * TODO(sjg@chromium.org): Use device tree for this?
173 int __weak board_i8042_skip(void)
175 /* As default, don't skip */
179 void i8042_flush(void)
184 * The delay is to give the keyboard controller some time
185 * to fill the next byte.
188 timeout = 100; /* wait for no longer than 100us */
189 while (timeout > 0 && !(in8(I8042_STS_REG) & STATUS_OBF)) {
194 /* Try to pull next byte if not timeout */
195 if (in8(I8042_STS_REG) & STATUS_OBF)
202 int i8042_disable(void)
204 if (kbd_input_empty() == 0)
207 /* Disable keyboard */
208 out8(I8042_CMD_REG, CMD_KBD_DIS);
210 if (kbd_input_empty() == 0)
216 static int i8042_kbd_check(struct input_config *input)
218 struct i8042_kbd_priv *priv = dev_get_priv(input->dev);
220 if ((in8(I8042_STS_REG) & STATUS_OBF) == 0) {
223 bool release = false;
227 scan_code = in8(I8042_DATA_REG);
228 if (scan_code == 0xfa) {
230 } else if (scan_code == 0xe0) {
231 priv->extended = true;
234 if (scan_code & 0x80) {
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;
251 input_add_keycode(input, scan_code, release);
256 /* i8042_kbd_init - reset keyboard and init state flags */
257 static int i8042_start(struct udevice *dev)
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;
266 if (!kbd_controller_present() || board_i8042_skip()) {
267 debug("i8042 keyboard controller is not present\n");
271 /* Init keyboard device (default US layout) */
273 penv = getenv("keymap");
275 if (strncmp(penv, "de", 3) == 0)
279 for (try = 0; kbd_reset(priv->quirks) != 0; try++) {
280 if (try >= KBD_RESET_TRIES)
284 ret = input_add_tables(input, keymap == KBD_GER);
288 i8042_kbd_update_leds(dev, NORMAL);
289 debug("%s: started\n", __func__);
295 * Set up the i8042 keyboard. This is called by the stdio device handler
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.
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().
304 * @return 0 if ok, -ve on error
306 static int i8042_kbd_probe(struct udevice *dev)
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;
314 if (fdtdec_get_bool(gd->fdt_blob, dev->of_offset,
315 "intel,duplicate-por"))
316 priv->quirks |= QUIRK_DUP_POR;
318 /* Register the device. i8042_start() will be called soon */
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);
325 debug("%s: input_stdio_register() failed\n", __func__);
328 debug("%s: ready\n", __func__);
333 static const struct keyboard_ops i8042_kbd_ops = {
334 .start = i8042_start,
335 .update_leds = i8042_kbd_update_leds,
338 static const struct udevice_id i8042_kbd_ids[] = {
339 { .compatible = "intel,i8042-keyboard" },
343 U_BOOT_DRIVER(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),