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.
Both pipe channels are currently configured as blocking. We read from the pipe
in receive_data. Since the channel is configured as blocking we'll block in
receive_data until all data has been received. receive_data will be called from
the mainloop, so as consequence the mainloop will be blocked until the demo
device has finished sampling. This is not so much of a problem if we are
sampling in blocking mode (using sr_session_run()) and the demo device is the
only device in the session, but it will fail badly for all other configurations
(e.g. multiple devices or async sampling).
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Free the USB transfers in the reverse order of which they were submitted. This
will avoid that while transfer 0 is cancelledd transfer 1 is started by the
host controller, and so on.
Reported-by: Peter Stuge <peter@stuge.se>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The session and demo device code contain a hack to make the demo device work on
Windows. This was neccessary since polling on windows requires special handling
and we can not just pass in the raw fd to poll.
With the previous patches which added support for non-fd based event sources
this hack is no longer required. The patch moves the GIOChannels used by the
demo device to the demo device context and uses sr_session_source_add_channel
to register a source for the channels instead of using the raw pipe fds.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
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.
Only one limit should be active at a time. Make sure that the sample limit is
disabled when a time limit is set and vice versa.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Call abort_acquisition if starting sampling fails in acquisition_start, this
will ensure that all already allocated resources are being freed again.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
This may happen if the acquisition_start is called right after calling
acquisition_stop and not all transfers have been freed or on repeated calls to
acquisition_start. If it happens we'll enter an undefined state and all kind of
strange behavior may occur, so error out in such a case.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The recent reworks of the fx2lafw made sure that the total buffer size is large
enough hold 500ms of data. This was done to improve performance and stability.
That the timeout value for a transfer was also increased to over 500ms, a side
effect of this is that when sampling is stopped there will be a additional delay
of 500ms. This is because the driver waits for all transfers to be freed
before it sends a SR_DF_END packet. Once sampling has stopped this will only
happen once a transfer times out. This patch cancels all pending transfers when
sampling is stopped, this will cause them to be freed almost immediately and the
additional delay will disappear.
Also make sure, that if we know, that we just have received the last transfer to
not resubmit this transfer again.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Currently timeout and buffer size are hard-coded in the fx2lafw driver which is
non-optimal if we want to get good results at both high and low sample rates.
The timeout is hard-coded to 40ms, which doesn't work well when sampling at
a low sample rate. E.g. at 20kHz filling all available buffer space alone takes
6 seconds. So naturally we'll see a lot of transfers timeout in this case.
The buffer size is hard-coded to 4096 bytes, which does not work well with high
sample rates. E.g. at 24MHz these 4096 bytes are enough space for 0.17ms of
data. The total buffer size is enough for about 5ms of data. Sooner or later the
application won't be able to resubmit a transfer within this time span and the
device will abort data acquisition. Usually this happens within the first few
seconds of sampling.
This patch adds a few new helper functions which calculate the buffer size and
timeout based on the current sample rate.
The buffer size is chosen to be large enough to hold about 10ms of data and it
also must be a multiple of 512 bytes since the firmware will send us the data
in 512 byte chunks.
The timeout is set to the time it would take to fill the whole available buffer
space plus a 25% headroom to accommodate for jitter. This is more than enough,
but there is no need to make the timeout a tight deadline, since it is only
meant as a last resort in case the device stops submitting data. And in this
case data acquisition will be aborted anyway.
The patch also limits the the number of transfers so that the total buffer
space is not much more of 500ms. This will ensure that we do not have to
wait too long when aborting data acquisition.
This patch also significantly reduces the number of context switches when
sampling at a higher sample rate. On my system for example the CPU load of
sigrok-cli when sampling at 24MHz goes down from ~25% to 3-4%.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
While errors are usually already implicitly caught by looking at the packet
length field there is one error status which is worth special handling. If the
device has been removed there is not really a chance to recover from this error
so data acquisition can be stopped immediately.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Bert Vermeulen
Ivan Fedorov
Uwe Hermann
Lars-Peter Clausen