2 * Chromium OS Matrix Keyboard
4 * Copyright (c) 2012 The Chromium OS Authors.
6 * SPDX-License-Identifier: GPL-2.0+
16 #include <key_matrix.h>
17 #include <stdio_dev.h>
19 DECLARE_GLOBAL_DATA_PTR
;
22 KBC_MAX_KEYS
= 8, /* Maximum keys held down at once */
23 KBC_REPEAT_RATE_MS
= 30,
24 KBC_REPEAT_DELAY_MS
= 240,
27 struct cros_ec_keyb_priv
{
28 struct input_config
*input
; /* The input layer */
29 struct key_matrix matrix
; /* The key matrix layer */
30 int key_rows
; /* Number of keyboard rows */
31 int key_cols
; /* Number of keyboard columns */
32 int ghost_filter
; /* 1 to enable ghost filter, else 0 */
37 * Check the keyboard controller and return a list of key matrix positions
38 * for which a key is pressed
40 * @param dev Keyboard device
41 * @param keys List of keys that we have detected
42 * @param max_count Maximum number of keys to return
43 * @param samep Set to true if this scan repeats the last, else false
44 * @return number of pressed keys, 0 for none, -EIO on error
46 static int check_for_keys(struct udevice
*dev
, struct key_matrix_key
*keys
,
47 int max_count
, bool *samep
)
49 struct cros_ec_keyb_priv
*priv
= dev_get_priv(dev
);
50 struct key_matrix_key
*key
;
51 static struct mbkp_keyscan last_scan
;
52 static bool last_scan_valid
;
53 struct mbkp_keyscan scan
;
54 unsigned int row
, col
, bit
, data
;
57 if (cros_ec_scan_keyboard(dev
->parent
, &scan
)) {
58 debug("%s: keyboard scan failed\n", __func__
);
61 *samep
= last_scan_valid
&& !memcmp(&last_scan
, &scan
, sizeof(scan
));
64 * This is a bit odd. The EC has no way to tell us that it has run
65 * out of key scans. It just returns the same scan over and over
66 * again. So the only way to detect that we have run out is to detect
67 * that this scan is the same as the last.
69 last_scan_valid
= true;
70 memcpy(&last_scan
, &scan
, sizeof(last_scan
));
72 for (col
= num_keys
= bit
= 0; col
< priv
->matrix
.num_cols
;
74 for (row
= 0; row
< priv
->matrix
.num_rows
; row
++) {
75 unsigned int mask
= 1 << (bit
& 7);
77 data
= scan
.data
[bit
/ 8];
78 if ((data
& mask
) && num_keys
< max_count
) {
79 key
= keys
+ num_keys
++;
92 * Check the keyboard, and send any keys that are pressed.
94 * This is called by input_tstc() and input_getc() when they need more
97 * @param input Input configuration
98 * @return 1, to indicate that we have something to look at
100 int cros_ec_kbc_check(struct input_config
*input
)
102 struct udevice
*dev
= input
->dev
;
103 struct cros_ec_keyb_priv
*priv
= dev_get_priv(dev
);
104 static struct key_matrix_key last_keys
[KBC_MAX_KEYS
];
105 static int last_num_keys
;
106 struct key_matrix_key keys
[KBC_MAX_KEYS
];
107 int keycodes
[KBC_MAX_KEYS
];
108 int num_keys
, num_keycodes
;
109 int irq_pending
, sent
;
113 * Loop until the EC has no more keyscan records, or we have
114 * received at least one character. This means we know that tstc()
115 * will always return non-zero if keys have been pressed.
117 * Without this loop, a key release (which generates no new ascii
118 * characters) will cause us to exit this function, and just tstc()
119 * may return 0 before all keys have been read from the EC.
122 irq_pending
= cros_ec_interrupt_pending(dev
->parent
);
124 num_keys
= check_for_keys(dev
, keys
, KBC_MAX_KEYS
,
128 last_num_keys
= num_keys
;
129 memcpy(last_keys
, keys
, sizeof(keys
));
132 * EC doesn't want to be asked, so use keys from last
135 num_keys
= last_num_keys
;
136 memcpy(keys
, last_keys
, sizeof(keys
));
141 num_keycodes
= key_matrix_decode(&priv
->matrix
, keys
,
142 num_keys
, keycodes
, KBC_MAX_KEYS
);
143 sent
= input_send_keycodes(input
, keycodes
, num_keycodes
);
146 * For those ECs without an interrupt, stop scanning when we
147 * see that the scan is the same as last time.
149 if ((irq_pending
< 0) && same
)
151 } while (irq_pending
&& !sent
);
157 * Decode MBKP keyboard details from the device tree
159 * @param blob Device tree blob
160 * @param node Node to decode from
161 * @param config Configuration data read from fdt
162 * @return 0 if ok, -1 on error
164 static int cros_ec_keyb_decode_fdt(const void *blob
, int node
,
165 struct cros_ec_keyb_priv
*config
)
168 * Get keyboard rows and columns - at present we are limited to
169 * 8 columns by the protocol (one byte per row scan)
171 config
->key_rows
= fdtdec_get_int(blob
, node
, "keypad,num-rows", 0);
172 config
->key_cols
= fdtdec_get_int(blob
, node
, "keypad,num-columns", 0);
173 if (!config
->key_rows
|| !config
->key_cols
||
174 config
->key_rows
* config
->key_cols
/ 8
175 > CROS_EC_KEYSCAN_COLS
) {
176 debug("%s: Invalid key matrix size %d x %d\n", __func__
,
177 config
->key_rows
, config
->key_cols
);
180 config
->ghost_filter
= fdtdec_get_bool(blob
, node
,
181 "google,needs-ghost-filter");
185 static int cros_ec_kbd_probe(struct udevice
*dev
)
187 struct cros_ec_keyb_priv
*priv
= dev_get_priv(dev
);
188 struct keyboard_priv
*uc_priv
= dev_get_uclass_priv(dev
);
189 struct stdio_dev
*sdev
= &uc_priv
->sdev
;
190 struct input_config
*input
= &uc_priv
->input
;
191 const void *blob
= gd
->fdt_blob
;
192 int node
= dev
->of_offset
;
195 if (cros_ec_keyb_decode_fdt(blob
, node
, priv
))
197 input_set_delays(input
, KBC_REPEAT_DELAY_MS
, KBC_REPEAT_RATE_MS
);
198 ret
= key_matrix_init(&priv
->matrix
, priv
->key_rows
, priv
->key_cols
,
201 debug("%s: cannot init key matrix\n", __func__
);
204 ret
= key_matrix_decode_fdt(&priv
->matrix
, gd
->fdt_blob
, node
);
206 debug("%s: Could not decode key matrix from fdt\n", __func__
);
209 debug("%s: Matrix keyboard %dx%d ready\n", __func__
, priv
->key_rows
,
214 input_add_tables(input
, false);
215 input
->read_keys
= cros_ec_kbc_check
;
216 strcpy(sdev
->name
, "cros-ec-keyb");
218 /* Register the device. cros_ec_init_keyboard() will be called soon */
219 return input_stdio_register(sdev
);
222 static const struct keyboard_ops cros_ec_kbd_ops
= {
225 static const struct udevice_id cros_ec_kbd_ids
[] = {
226 { .compatible
= "google,cros-ec-keyb" },
230 U_BOOT_DRIVER(cros_ec_kbd
) = {
231 .name
= "cros_ec_kbd",
232 .id
= UCLASS_KEYBOARD
,
233 .of_match
= cros_ec_kbd_ids
,
234 .probe
= cros_ec_kbd_probe
,
235 .ops
= &cros_ec_kbd_ops
,
236 .priv_auto_alloc_size
= sizeof(struct cros_ec_keyb_priv
),