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aa669fa25d
If you call *usb_host_device_close()* for a device that isn't open, the function exits early,
without giving back the semaphore it took, which causes any other call that tries to take
that semaphore to hang indefinitely.
Strangely, there's redundant handling of this condition, with two checks in a row that both handle
the case where `_check_client_opened_device(client_obj, dev_addr)` returns `false`:
```c
HOST_CHECK_FROM_CRIT(_check_client_opened_device(client_obj, dev_addr), ESP_ERR_NOT_FOUND);
if (!_check_client_opened_device(client_obj, dev_addr)) {
// Client never opened this device
ret = ESP_ERR_INVALID_STATE;
HOST_EXIT_CRITICAL();
goto exit;
}
…
exit:
xSemaphoreGive(p_host_lib_obj->constant.mux_lock);
return ret;
```
The first line is the one that exits early, as HOST_CHECK_FROM_CRIT returns its second parameter
if its first parameter is false, without giving back the semaphore (although it does exit
the critical section).
The subsequent block handles the exact same case, except that it ensures the semaphore is given
back before returning. Currently, this block is never reached.
Perhaps the first check was added, then someone noticed the issue and added the second check,
but they forgot to remove the first one.
In any case, this PR removes the first check, so the second check can properly handle this case
by giving back the semaphore before returning.
This bug appears to have been present in the initial commit of the USB Host library to the ESP-IDF
repo: accbaee57c
Of course, if you never try to close a non-opened device, then you won't encounter it!
Unfortunately, I have some code that tried to do that, which is how I found the issue.