diff options
| -rw-r--r-- | drivers/input/cros_ec_keyb.c | 34 |
1 files changed, 30 insertions, 4 deletions
diff --git a/drivers/input/cros_ec_keyb.c b/drivers/input/cros_ec_keyb.c index e8dac237a9..a2501e0206 100644 --- a/drivers/input/cros_ec_keyb.c +++ b/drivers/input/cros_ec_keyb.c @@ -8,6 +8,7 @@ #include <common.h> #include <cros_ec.h> +#include <errno.h> #include <fdtdec.h> #include <input.h> #include <key_matrix.h> @@ -39,20 +40,34 @@ static struct keyb { * @param config Keyboard config * @param keys List of keys that we have detected * @param max_count Maximum number of keys to return - * @return number of pressed keys, 0 for none + * @param samep Set to true if this scan repeats the last, else false + * @return number of pressed keys, 0 for none, -EIO on error */ static int check_for_keys(struct keyb *config, - struct key_matrix_key *keys, int max_count) + struct key_matrix_key *keys, int max_count, + bool *samep) { struct key_matrix_key *key; + static struct mbkp_keyscan last_scan; + static bool last_scan_valid; struct mbkp_keyscan scan; unsigned int row, col, bit, data; int num_keys; if (cros_ec_scan_keyboard(config->dev, &scan)) { debug("%s: keyboard scan failed\n", __func__); - return -1; + return -EIO; } + *samep = last_scan_valid && !memcmp(&last_scan, &scan, sizeof(scan)); + + /* + * This is a bit odd. The EC has no way to tell us that it has run + * out of key scans. It just returns the same scan over and over + * again. So the only way to detect that we have run out is to detect + * that this scan is the same as the last. + */ + last_scan_valid = true; + memcpy(&last_scan, &scan, sizeof(last_scan)); for (col = num_keys = bit = 0; col < config->matrix.num_cols; col++) { @@ -112,6 +127,7 @@ int cros_ec_kbc_check(struct input_config *input) int keycodes[KBC_MAX_KEYS]; int num_keys, num_keycodes; int irq_pending, sent; + bool same = false; /* * Loop until the EC has no more keyscan records, or we have @@ -125,7 +141,10 @@ int cros_ec_kbc_check(struct input_config *input) do { irq_pending = cros_ec_interrupt_pending(config.dev); if (irq_pending) { - num_keys = check_for_keys(&config, keys, KBC_MAX_KEYS); + num_keys = check_for_keys(&config, keys, KBC_MAX_KEYS, + &same); + if (num_keys < 0) + return 0; last_num_keys = num_keys; memcpy(last_keys, keys, sizeof(keys)); } else { @@ -142,6 +161,13 @@ int cros_ec_kbc_check(struct input_config *input) num_keycodes = key_matrix_decode(&config.matrix, keys, num_keys, keycodes, KBC_MAX_KEYS); sent = input_send_keycodes(input, keycodes, num_keycodes); + + /* + * For those ECs without an interrupt, stop scanning when we + * see that the scan is the same as last time. + */ + if ((irq_pending < 0) && same) + break; } while (irq_pending && !sent); return 1; |