xref: /openbmc/u-boot/drivers/input/i8042.c (revision 18e02ffe)
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 };
351