The previous implementation seems to have added drivers in their "order
of appearance". Start sorting the rather long list, to simplify several
tasks: Add new entries as more drivers get written, find existing items
during research, identify and compare similar models during maintenance.
As a byproduct, there will be no doubt about where to put things during
future work :) and duplicates will be spotted immediately.
This commit puts 'bm25x' meters into one group. And comments on the sort
order and motivation for sorting the table.
Add another DMM entry for Peaktech-3330, which is based on the FS9721
chipset. Support was tested with the CP210x based USB cable.
Signed-off-by: Gerhard Sittig <gerhard.sittig@gmx.net>
We now require the use of the latest fx2lafw firmware which uses the
same USB VID/PID (1D50:608E) for the Hantek 6022BE and the variants
and rebadges of that device (e.g. the SainSmart DDS120).
The variants can be distinguished via the USB product version field.
This allows much faster and configurable sampling rate, and faster
reaction to function switch.
This also gives a more repeatable job ordering and more reliable
query/reply association.
Fix the array size check in the sigma_write_register() routine. The
'len' parameter specifies the number of bytes to write, while the 'buf'
array holds one nibble per array item.
The previous implementation (commit e8686e3ae3) switched to a
constant size and made the buffer large enough so that no existing
request would exceed the buffer, fixing an overflow that was present
before that commit. But the most recent size check was incomplete and
might erroneously succeed for larger amounts of write data.
It's assumed that the issue which gets addressed here never occured in
practice. The constant-size buffer could hold up to 39 bytes of input
data in their transport representation, while the largest data that was
passed to the write routine is six bytes (trigger LUT params).
Fixes: e8686e3ae3 "asix-sigma: Avoid use of variable length arrays"
Signed-off-by: Gerhard Sittig <gerhard.sittig@gmx.net>
The driver internally implements the "limit samples" feature by means of
the "limit sample period" approach. Determination of the corresponding
period of time for captures depends on the sample rate as well as the
maximum sample count, and thus needs to be re-done when either setting
changes.
Introduce a "limit_samples" variable so that the value is available when
needed later. As a byproduct the parameter can be retrieved now (get).
Add comments to the sigma_set_samplerate() routine's sections, since
quite a bit is happening there, and interacts with other locations.
Signed-off-by: Gerhard Sittig <gerhard.sittig@gmx.net>
Commit 2c9c0df86e removed the sentinel from the samplerates[] array,
but did not adjust the test which checked whether a rate is listed in
the set of supported rates. This could result in an out-of-range access
beyond the array's last item.
Fix the "listed?" check after iterating the table of supported rates.
Cope with either presence or absence of a sentinel in the array.
Address some more style nits while we are here. Rename an identifier
for a local variable which unintentionally might suggest that it would
be a preprocessor macro (all-caps). Reduce redundancy in data type
references as well as in the determination of the array size.
Signed-off-by: Gerhard Sittig <gerhard.sittig@gmx.net>
The current implementation of the ASIX Sigma firmware download contains
comments which express uncertainty. Rephrase them, no magic is involved.
Discuss the polarity of the CCLK hardware signal. Which shall eliminate
potential concerns in future reviews or maintenance.
This commit only updates comments, and does not change behaviour.
Signed-off-by: Gerhard Sittig <gerhard.sittig@gmx.net>
The default so far was 0, which meant there would be no significant
digits at all, yielding results that looked strange/wrong to the user.
Long-term all remaining drivers should be fixed to use the actual,
correct digits and spec_digits values according to the device's
capabilities and/or datasheet/manual. Until that is done, a default
of digits=2 is used as a temporary workaround.
This fixes the remaining parts of bug #815.
Gerhard Sittig
Uwe Hermann
Aurelien Jacobs
Karsten König