alsa: Find supported samplerates during device scan
Since we are using the 'hw' interface of ALSA, we don't have the luxury of
samplerate conversion, given by the 'plughw' interface. If we try to set a
samplerate that is not supported, ALSA will just throw an error.
We can test for the supported samplerates, and create a list of supported
samplerates, then limit the selection to only those values. The frontend can
query the list of supported samplerates.
alsa: Fix sample acquisition and send normalized values
The alsa driver requested signed 16-bit integers from ALSA, but casted them to
to an unsigned 16bit before finally casting them to a float. The end result was
that half of the wave would be clipped off.
We also requested data in little endian format. ALSA can be instructed to send
data with the correct endianness for the platform, without needing to worry
about what that is.
This patch attempts three points, which, together, fix the acquisition:
1) Request data from ALSA without specifying endianness; ALSA will handle the
endianness.
2) Simplify the int16_t to float loop by using straightforward indexes.
3) Normalize every value before sending it on the session bus.
NOTE: If testing with PulseView, it will appear as if sigrok is sending all
zeroes. sigrok is sending correct data, but since the data is normalized,
PulseView will incorrectly plot it as a straight line.
alsa: Scan all soundcards and create a sigrok device per input
The alsa driver only works with device "default". This limits the driver's
scope to whatever device ALSA deems to be "default". It is desirable to have
access to all ALSA devices from sigrok.
Change the alsa device scan so that:
Each alsa device (not alsa card) gets its own sigrok device
For example,
hw:1,0 == sigrok device 0
hw:1,1 == sigrok device 1
hw:2,0 == sigrok device 2
hw:2,1 == sigrok device 3
hw:2,2 == sigrok device 4
[...]
We don't currently look at alsa subdevices. We only use subdevice 0.
Every input device will have its own channels (left, right, etc). Each of
those channels gets mapped to a different sigrok probe. A device with 4
channels will have 4 probes from sigrok's perspective.
alsa: Do not use snd_pcm_hw_params_set_rate_near()
snd_pcm_hw_params_set_rate_near() will try to use the samplerate closest to the
given value, potentially starting the acquisition with a different samplerate
than the one specified.
Instead, use snd_pcm_hw_params_set_rate(). It will return an error if the
samplerate is not supported by the hardware, which is arguably better than
collecting data with a different samplerate than the one specified.
Uwe Hermann [Wed, 19 Dec 2012 21:50:07 +0000 (22:50 +0100)]
serial-dmm: Rename VOLTCRAFT_VC820 to VOLTCRAFT_VC820_SER.
This matches the _ser suffix of the other functions/variables for this
device ("ser" denotes that it is used with the serial UNI-T UT-D02 cable
as opposed the USB/HID based cables which are handled by the uni-t-dmm driver).
But more importantly, the _SER suffix for the enum value will prevent
name clashes later, when the uni-t-dmm driver gets a VOLTCRAFT_VC820 enum.
Uwe Hermann [Wed, 26 Dec 2012 00:29:27 +0000 (01:29 +0100)]
Fix limit_samples check in various drivers.
Check whether a sample limit was actually set (> 0) before checking if
that sample limit is reached. This also fixes continuous acquisition mode
for drivers which have that.
Some unusual modes required re-parsing the value. Instead of assigning the
re-parsed value to *floatval, it was reassigned directly to *analog->data;
however, analog->data is not initialized at this point, causing a segfault.
This situation was created when moving the radioshack-dmm code to serial-dmm,
with the segfault not being observed at that time.
Do not write directly to analog->data, but instead use the intermediate
variable rawval.
Convert bit masks from hardcoded hex values to bit shifts. For example 0x80
becomes (1 << 7). This also fixes a typo error in the definition of INFO_DIODE.
Add comments explaining that some case values in sr_rs9lcd_parse() are meant to
fall through without a 'break;', and explain some of the unusual modes.
Bert Vermeulen [Tue, 25 Dec 2012 18:09:12 +0000 (19:09 +0100)]
nexus-osciprime: basic scanning functionality
Unfortunately the device doesn't have an EEPROM on board at all, and so
initially enumerates with the default Cypress FX2 VID:PID (04b4:8613).
Since we already support using plain FX2* as basic logic analyzers using
the fx2lafw firmware, we cannot support that same VID:PID for the
OsciPrime. Therefore a USB conn is required for the initial scan.
However, once the firmware is uploaded the device re-enumerates as
04b4:1004, which we do detect for scanning automatically.
Thus, the OsciPrime driver requires one scan with conn parameter to get
the firmware uploaded, but it will then keep working until powered off.
session.c: Remove all remaining sources on sr_session_stop
Some sources may not be necessarily associated with a device. The best example
is the anykey pollfd from sigrok-cli. sr_session_stop only removes sources
associated with hardware devices via dev_acquisition_stop. Sources such as
anykey are not removed, and thus session->num_sources will not get to 0. As a
result, we may get into situations where the event loop enters an infinite
state.
To prevent this, all we have to do is remove any active sources that are still
present after dev_acquisition_stop has been called for all devices.
device.c: Fix memory leak in sr_serial_dev_inst_free
sr_serial_dev_inst_free() freed all members of sr_serial_dev_inst, but did not
free the struct itself, as expected from a free_*() function. This inadvertently
caused a memory leak in every place sr_serial_dev_inst is used.
serial-dmm does not check if a sample limit is actually in place before deciding
to stop acquisition. Since the sample limit is set at 0 by default, operating
in continuous mode will cause acquisition to stop before even sending the first
sample.
Check to make sure we actually are in a sample-limited mode before stopping for
this reason.
Uwe Hermann [Sat, 22 Dec 2012 00:33:03 +0000 (01:33 +0100)]
configure.ac: Improve check for libusb-1.0.
PKG_CHECK_MODULES() checks for libusb-1.0 via pkg-config already, no
need to use a "manual" additional check via AC_CHECK_LIB() just to set
HAVE_LIBUSB_1_0 in config.h.
This helps with cross-compiling setups, among other things.
Joel Holdsworth [Thu, 13 Dec 2012 21:07:53 +0000 (21:07 +0000)]
Pass sr_datafeed_packets and payloads with const pointers
This patch marks packet structures and their payloads as const.
This indicates to packet receivers that modifications to these are
not allowed. In general all pointers should be marked const unless
modification of the referenced data is explicitly allowed.
Hardware scanning creates an ftdi_context before attempting to locate devices
based on PID/VID. If no devices are detected, execution jumps to cleanup. The
context is freed with free(), instead of ftdi_free().
We cannot assume that the libftdi context is stored in a contiguous memory
region, and thus cannot use a simple free. Case in point, this situation is
identified by valgrind as a "definitely lost" memory leak.
Use ftdi_free() instead of a simple free() in hw_scan(). Valgrind no longer
complains about a memory leak in this area.
clear_instances() does not need any modification, as it correctly uses
ftdi_free().
It solved that issue, but inadvertently introduced a new bug:
"Device came back" would be printed even if no firmware upload was performed.
This is counterintuitive, as the device is only reset when a firmware upload is
performed.
There are three cases:
i) Firmware upload was successful
ii) Firmware upload failed
iii) Firmware upload was NOT needed
Each case warrants a separate message from the driver. Print the
following messages depending on the outcome:
i) "Device came back"
ii) "Device failed to renumerate"
iii) "Firmware upload was not needed."
Uwe Hermann [Sun, 16 Dec 2012 20:28:26 +0000 (21:28 +0100)]
serial-dmm: Eliminate unneeded "subdriver" field.
Just use the 'int dmm' + wrapper method that is used for all other
functions which need this information. There is no real need to
special-case the hw_dev_acquisition_start() API call here.
linsigrok.h: Document meaning of SR_UNIT_CONCENTRATION
Having concentration as a unit is vague, as it can be expressed in
many ways. In the context of sigrok, concentration means a normalized
number from 0 to 1.
libsigrok.h: Don't store subdriver in sr_dev_driver
Not all drivers use subdrivers. The only reason the subdriver field was
introduced was to accomodate the model of serial-dmm.
The sr_dev_driver struct is available to the frontend. Exposing the subdriver
field creates the problem of exposing knowledge of libsigrok's internal driver
layout, even though the drivers are designed to be a flat list to the frontend.
Store the subdriver in the dev_context struct of serial-dmm.
The global *di alias was used to keep track of the driver context.
It caused issues with trying to use several subdrivers at once, so
its use was obsoleted.
The correct context is preserved through different mechanisms, either
the *sdi pointer, or wrappers which pass the correct context.
Wrappers for hw_init, hw_cleanup, clear_instances, and hw_scan are needed for
each subdriver due to the nature of serial-dmm. These wrappers are implemented
as macros, in order to reduce the number of lines of code.
For each of those functions, we have a separate wrapper list, then we connect
them together in a first-class driver using a DRV macro, and yet another list
(the DRV list).
Instead of declaring those wrappers in separate lists, include them in the DRV
macro. This approach reduces the number of macro lists from five to just one.
From the perspective of adding a new subdriver, this also greatly reduces the
number of places needed to hook in a new device.
Uwe Hermann [Tue, 11 Dec 2012 16:06:04 +0000 (17:06 +0100)]
serial-dmm: Simplify code a bit.
Store/use the receive_data() function and a pointer to the driver struct
in the dmms[] array. Use a ".subdriver" entry in the driver struct.
Use a macro to simplify hw_init() wrappers.
di was initialized as NULL. If no device covered by this driver
is used, di remains NULL. This causes a segmentation fault when
calling clear_instances().
Peter Stuge [Sat, 3 Nov 2012 07:27:48 +0000 (08:27 +0100)]
backend.c: Fix memory leak in sr_init() error path
Commit 785b9ff290cbdb86e7d0b0280c33b43faf9c0518 added libusb init into
sr_init() which can generate an error. In this case, the already
allocated struct sr_context would have leaked.
projects / libsigrok.git / log