input: Add ANSI 3.64 escape sequence generation.

To support Non-ASCII keys (ex, Fn, PgUp/Dn, arrow keys, ...), we need to
translate key code into escape sequence.

(Updated by sjg@chromium.org to move away from a function to store
keycodes, so we can easily record how many were sent. We now need to
return this from input_send_keycodes() so we know whether keys were
generated.)

Signed-off-by: Hung-Te Lin <hungte@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Rini <trini@ti.com>
This commit is contained in:
Hung-Te Lin 2012-10-11 15:15:53 +00:00 committed by Tom Rini
parent 59a1b72ced
commit 44abe47deb
2 changed files with 89 additions and 15 deletions

View File

@ -93,6 +93,22 @@ static unsigned char kbd_ctrl_xlate[] = {
'\r', 0xff, 0xff
};
/*
* Scan key code to ANSI 3.64 escape sequence table. This table is
* incomplete in that it does not include all possible extra keys.
*/
static struct {
int kbd_scan_code;
char *escape;
} kbd_to_ansi364[] = {
{ KEY_UP, "\033[A"},
{ KEY_DOWN, "\033[B"},
{ KEY_RIGHT, "\033[C"},
{ KEY_LEFT, "\033[D"},
};
/* Maximum number of output characters that an ANSI sequence expands to */
#define ANSI_CHAR_MAX 3
int input_queue_ascii(struct input_config *config, int ch)
{
@ -289,24 +305,67 @@ static int input_check_keycodes(struct input_config *config,
}
/**
* Checks and converts a special key code into ANSI 3.64 escape sequence.
*
* @param config Input state
* @param keycode Key code to examine
* @param output_ch Buffer to place output characters into. It should
* be at least ANSI_CHAR_MAX bytes long, to allow for
* an ANSI sequence.
* @param max_chars Maximum number of characters to add to output_ch
* @return number of characters output, if the key was converted, otherwise 0.
* This may be larger than max_chars, in which case the overflow
* characters are not output.
*/
static int input_keycode_to_ansi364(struct input_config *config,
int keycode, char output_ch[], int max_chars)
{
const char *escape;
int ch_count;
int i;
for (i = ch_count = 0; i < ARRAY_SIZE(kbd_to_ansi364); i++) {
if (keycode != kbd_to_ansi364[i].kbd_scan_code)
continue;
for (escape = kbd_to_ansi364[i].escape; *escape; escape++) {
if (ch_count < max_chars)
output_ch[ch_count] = *escape;
ch_count++;
}
return ch_count;
}
return 0;
}
/**
* Converts and queues a list of key codes in escaped ASCII string form
* Convert a list of key codes into ASCII
*
* You must call input_check_keycodes() before this. It turns the keycode
* list into a list of ASCII characters which are ready to send to the
* input layer.
* list into a list of ASCII characters and sends them to the input layer.
*
* Characters which were seen last time do not generate fresh ASCII output.
* The output (calls to queue_ascii) may be longer than num_keycodes, if the
* keycode contains special keys that was encoded to longer escaped sequence.
*
* @param config Input state
* @param keycode List of key codes to examine
* @param num_keycodes Number of key codes
* @param output_ch Buffer to place output characters into. It should
* be at last ANSI_CHAR_MAX * num_keycodes, to allow for
* ANSI sequences.
* @param max_chars Maximum number of characters to add to output_ch
* @param same Number of key codes which are the same
* @return number of characters written into output_ch, or -1 if we would
* exceed max_chars chars.
*/
static int input_keycodes_to_ascii(struct input_config *config,
int keycode[], int num_keycodes, char output_ch[], int same)
int keycode[], int num_keycodes, char output_ch[],
int max_chars, int same)
{
struct input_key_xlate *table;
int ch_count;
int ch_count = 0;
int i;
table = &config->table[0];
@ -321,19 +380,31 @@ static int input_keycodes_to_ascii(struct input_config *config,
}
}
/* now find normal keys */
for (i = ch_count = 0; i < num_keycodes; i++) {
/* Start conversion by looking for the first new keycode (by same). */
for (i = same; i < num_keycodes; i++) {
int key = keycode[i];
int ch = (key < table->num_entries) ? table->xlate[key] : 0xff;
if (key < table->num_entries && i >= same) {
int ch = table->xlate[key];
/* If a normal key with an ASCII value, add it! */
if (ch != 0xff)
output_ch[ch_count++] = (uchar)ch;
/*
* For a normal key (with an ASCII value), add it; otherwise
* translate special key to escape sequence if possible.
*/
if (ch != 0xff) {
if (ch_count < max_chars)
output_ch[ch_count] = (uchar)ch;
ch_count++;
} else {
ch_count += input_keycode_to_ansi364(config, key,
output_ch, max_chars);
}
}
if (ch_count > max_chars) {
debug("%s: Output char buffer overflow size=%d, need=%d\n",
__func__, max_chars, ch_count);
return -1;
}
/* ok, so return keys */
return ch_count;
}
@ -341,7 +412,7 @@ static int input_keycodes_to_ascii(struct input_config *config,
int input_send_keycodes(struct input_config *config,
int keycode[], int num_keycodes)
{
char ch[num_keycodes];
char ch[num_keycodes * ANSI_CHAR_MAX];
int count, i, same = 0;
int is_repeat = 0;
unsigned delay_ms;
@ -363,7 +434,7 @@ int input_send_keycodes(struct input_config *config,
}
count = input_keycodes_to_ascii(config, keycode, num_keycodes,
ch, is_repeat ? 0 : same);
ch, sizeof(ch), is_repeat ? 0 : same);
for (i = 0; i < count; i++)
input_queue_ascii(config, ch[i]);
delay_ms = is_repeat ?
@ -371,7 +442,8 @@ int input_send_keycodes(struct input_config *config,
config->repeat_delay_ms;
config->next_repeat_ms = get_timer(0) + delay_ms;
return 0;
return count;
}
int input_add_table(struct input_config *config, int left_keycode,

View File

@ -84,6 +84,8 @@ struct stdio_dev;
* @param config Input state
* @param keycode List of key codes to examine
* @param num_keycodes Number of key codes
* @return number of ascii characters sent, or 0 if none, or -1 for an
* internal error
*/
int input_send_keycodes(struct input_config *config, int keycode[], int count);