diff options
| -rw-r--r-- | common/keyboard_8042.c | 28 |
1 files changed, 26 insertions, 2 deletions
diff --git a/common/keyboard_8042.c b/common/keyboard_8042.c index 78a20dc479..0d8192b166 100644 --- a/common/keyboard_8042.c +++ b/common/keyboard_8042.c @@ -59,6 +59,9 @@ enum scancode_set_list { #define MAX_SCAN_CODE_LEN 4 +/* Number of bytes host can get behind before we start generating extra IRQs */ +#define KB_TO_HOST_RETRIES 3 + /* * Mutex to control write access to the to-host buffer head. Don't need to * mutex the tail because reads are only done in one place. @@ -891,6 +894,7 @@ static void keyboard_special(uint16_t k) void keyboard_protocol_task(void) { int wait = -1; + int retries = 0; reset_rate_and_delay(); @@ -926,9 +930,28 @@ void keyboard_protocol_task(void) if (queue_is_empty(&to_host)) break; - /* Host interface must have space */ - if (lpc_keyboard_has_char()) + /* Handle data waiting for host */ + if (lpc_keyboard_has_char()) { + /* If interrupts disabled, nothing we can do */ + if (!i8042_irq_enabled) + break; + + /* Give the host a little longer to respond */ + if (++retries < KB_TO_HOST_RETRIES) + break; + + /* + * We keep getting data, but the host keeps + * ignoring us. Fine, we're done waiting. + * Hey, host, are you ever gonna get to this + * data? Send it another interrupt in case it + * somehow missed the first one. + */ + CPRINTF("[%T KB extra IRQ]\n"); + lpc_keyboard_resume_irq(); + retries = 0; break; + } /* Get a char from buffer. */ kblog_put('k', to_host.head); @@ -937,6 +960,7 @@ void keyboard_protocol_task(void) /* Write to host. */ lpc_keyboard_put_char(chr, i8042_irq_enabled); + retries = 0; } } } |