Serial detection was using serial_readline, which stripped carriage
return from the packets. This made for a very unreliable detection
mechanism.
Switch to a timeout-based detection mechanism that parses the data
as it comes in. This also allows us to stop parsing once we found
our first valid packet.
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
In the case of USB drivers, a driver's dev_acquisition_stop() cannot
simply remove its fd sources from the session and close its devices:
a USB transfer might still be underway, and it needs to be finished
(and its memory freed) properly.
An sr_dev_inst->status value is added: SR_ST_STOPPING, which should
be set when the driver's dev_acquisition_stop() is called, and acts
as a marker for the USB event handler to wind up its operations.
In order for dev_acquisition_stop() to be able to set the sdi status,
however, it needs to be unconstified.
Merge parts of the tekpower-dmm code (the chip of the TekPower
TP4000ZC seems to be an FS9721_LP3 too) and rework parts of the functions.
Adapt the tekpower-dmm and uni-t-dmm code accordingly.
Uwe Hermann
Alexandru Gagniuc
Bert Vermeulen