Merge remote-tracking branch 'origin/master' into develop

This commit is contained in:
QMK Bot 2021-04-25 03:12:09 +00:00
commit 64a9cf18e1
3 changed files with 33 additions and 21 deletions

View File

@ -80,19 +80,7 @@ static bool qmkusb_start_receive(QMKUSBDriver *qmkusbp) {
* Interface implementation.
*/
static size_t _write(void *ip, const uint8_t *bp, size_t n) {
output_buffers_queue_t *obqueue = &((QMKUSBDriver *)ip)->obqueue;
chSysLock();
const bool full = obqIsFullI(obqueue);
chSysUnlock();
if (full || bqIsSuspendedX(obqueue)) {
/* Discard any writes while the queue is suspended or full, i.e. the hidraw
interface is not open. If we tried to send with an infinite timeout, we
would deadlock the keyboard otherwise. */
return -1;
}
return obqWriteTimeout(obqueue, bp, n, TIME_INFINITE);
}
static size_t _write(void *ip, const uint8_t *bp, size_t n) { return obqWriteTimeout(&((QMKUSBDriver *)ip)->obqueue, bp, n, TIME_INFINITE); }
static size_t _read(void *ip, uint8_t *bp, size_t n) { return ibqReadTimeout(&((QMKUSBDriver *)ip)->ibqueue, bp, n, TIME_INFINITE); }

View File

@ -930,9 +930,32 @@ void send_consumer(uint16_t data) {
#ifdef CONSOLE_ENABLE
int8_t sendchar(uint8_t c) {
// The previous implmentation had timeouts, but I think it's better to just slow down
// and make sure that everything is transferred, rather than dropping stuff
return chnWrite(&drivers.console_driver.driver, &c, 1);
static bool timed_out = false;
/* The `timed_out` state is an approximation of the ideal `is_listener_disconnected?` state.
*
* When a 5ms timeout write has timed out, hid_listen is most likely not running, or not
* listening to this keyboard, so we go into the timed_out state. In this state we assume
* that hid_listen is most likely not gonna be connected to us any time soon, so it would
* be wasteful to write follow-up characters with a 5ms timeout, it would all add up and
* unncecessarily slow down the firmware. However instead of just dropping the characters,
* we write them with a TIME_IMMEDIATE timeout, which is a zero timeout,
* and this will succeed only if hid_listen gets connected again. When a write with
* TIME_IMMEDIATE timeout succeeds, we know that hid_listen is listening to us again, and
* we can go back to the timed_out = false state, and following writes will be executed
* with a 5ms timeout. The reason we don't just send all characters with the TIME_IMMEDIATE
* timeout is that this could cause bytes to be lost even if hid_listen is running, if there
* is a lot of data being sent over the console.
*
* This logic will work correctly as long as hid_listen is able to receive at least 200
* bytes per second. On a heavily overloaded machine that's so overloaded that it's
* unusable, and constantly swapping, hid_listen might have trouble receiving 200 bytes per
* second, so some bytes might be lost on the console.
*/
const sysinterval_t timeout = timed_out ? TIME_IMMEDIATE : TIME_MS2I(5);
const size_t result = chnWriteTimeout(&drivers.console_driver.driver, &c, 1, timeout);
timed_out = (result == 0);
return result;
}
// Just a dummy function for now, this could be exposed as a weak function

View File

@ -829,9 +829,10 @@ static void send_consumer(uint16_t data) {
* FIXME: Needs doc
*/
int8_t sendchar(uint8_t c) {
// Not wait once timeouted.
// Do not wait if the previous write has timed_out.
// Because sendchar() is called so many times, waiting each call causes big lag.
static bool timeouted = false;
// The `timed_out` state is an approximation of the ideal `is_listener_disconnected?` state.
static bool timed_out = false;
// prevents Console_Task() from running during sendchar() runs.
// or char will be lost. These two function is mutually exclusive.
@ -845,11 +846,11 @@ int8_t sendchar(uint8_t c) {
goto ERROR_EXIT;
}
if (timeouted && !Endpoint_IsReadWriteAllowed()) {
if (timed_out && !Endpoint_IsReadWriteAllowed()) {
goto ERROR_EXIT;
}
timeouted = false;
timed_out = false;
uint8_t timeout = SEND_TIMEOUT;
while (!Endpoint_IsReadWriteAllowed()) {
@ -860,7 +861,7 @@ int8_t sendchar(uint8_t c) {
goto ERROR_EXIT;
}
if (!(timeout--)) {
timeouted = true;
timed_out = true;
goto ERROR_EXIT;
}
_delay_ms(1);