The CDC descriptor was not advertising support the the line
coding and serial state messages. This was preventing Mac
from sending the SetControlLineState message to indicate
that a DTE (ie terminal program) was present and reading
from the serial port.
We support (and depend on) the DTE indication now so this
was making CDC not work on Mac.
Linux seems to provide the indication regardless of whether
it is advertised in the descriptor or not.
CDC and USART device drivers were not all clearing their
device structs before using them.
This specifically caused crashes in the case where the upper
COM layer was binding only a Tx path. The Rx path callback
in the lower driver was uninitialized random data and would
result in the lower driver faulting when it tried to call the
callback.
Conflicts:
flight/PiOS/STM32F30x/pios_usart.c
flight/PiOS/STM32F30x/pios_usb_cdc.c
flight/PiOS/STM32F30x/pios_usb_hid.c
The CDC layer on F1, F3 and F4 now always acts like an
infinte data sink whenever *either* there is no DTE present
(ie. no terminal program listening) *or* the USB cable is
disconnected.
F1 and F4 were previously checking the cable but not the DTE.
F3 didn't check anything. The COM layer didn't even ask the
lower layers.
All of this used to mean that any time a caller did a blocking
send to a CDC device without a DTE, it would eventually block
for up to a 5s timeout waiting for space in the Tx buffer.
Conflicts:
flight/PiOS/STM32F30x/pios_usb_cdc.c
This move and rework also breaks the dependency of the task monitor on the UAVO subsystem,
and pushes the responsibility for updating the TaskInfo UAVO into the System module.
+review OPReview
Also fixes warnings (and bugs) in F4 STM32_USB_OTG_Driver code, allowing -Werror to be enabled for all flight code.
Fixes all other compiler warnings that would otherwise cause the flight code to not compile with -Werror enabled.
Along the way, this also adds some uses of isnan() to various places rather than questionable tests for x != x and
x == x to check for NaNs.
+review OPReview
