ols driver used to probe a series of available serial ports obtained
by regexp matching of common serial port names.
There are a number of problems with this approach:
1. It will probe all serial devices, including devices that do not
like to be probed, potentially causing them to act up.
2. It will try to probe serial ports which may already be opened in
other applications for other purposes.
3. It assumes the naming of the serial ports is set in stone, and
creates an unnecessary OS-specific list.
4. It produces unnecessary debug output even when an OLS device is
not connected.
5. etc...
Do not implicitly probe serial ports. Only probe the port specified
by the frontend, if any; otherwise, just quit.
Also get rid of all functionality in serial.c which was designed
specifically for random probing.
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.
These are used to list the device instances currently known to the driver,
and clear that list.
Drivers that don't necessarily clear their list of instances on every scan,
such as genericdmm, need to provide these to the frontend to keep instance
management sane.
Since probes now live in a struct sr_dev_inst owned by the driver, it
already knows about them. Instead of a frontend telling the driver to
configure probes, all driver now do this just before starting acquisition.
It's obsolete: no frontend ever used it, and neither did libsigrok.
The sdi->status field is only used internally by some drivers, and
should probably be moved to the driver-specific context structs.
This changes the semantics of the init() call as well. That now only
initializes the driver -- an administrative affair, no hardware gets
touched during this call. It returns a standard SR_OK or SR_ERR* code.
The scan() call does a discovery run for devices it knows, and returns
the number found. It can be called at any time.
It was actually used in one way: the session file loaded abused it for
passing in the filename -- something it definitely wasn't intended for.
This now uses the proper way to pass arguments to a driver: the new
SR_HWCAP_SESSIONFILE.
The OLS driver could also use it as an indication of the serial port to
use instead of actively probing all serial ports on the system, but there
wasn't any frontend code that passed in such a parameter, making it
entirely useless. That will soon be handled differently with the new
scan() API call, regardless.
All frontends will have to include <libsigrok/libsigrok.h> from now on.
This header includes proto.h and version.h, both installed from the
distribution into $INCLUDE/libsigrok/ as well.
The only dynamically changed header is now version.h, which has both
libsigrok and libtool compile-time versions in it.
Start/stop acquisition callbacks: Consistently name the 'void *' parameter
cb_data for now. The per-device-instance device pointer is called
'session_dev_id' everywhere for now, but this should be renamed to
something more clear.