These calls were already nonblocking since this driver opened the port with
the SERIAL_NONBLOCK flag. Having marked them as such, we can remove the flag.
Also remove an unnecessary reopen of the port to change its blocking status.
Every driver now publishes its device option config keys, i.e. the
list fetched with sr_config_list(SR_CONF_DEVICE_OPTIONS), with a
set of flags indicating which methods are implemented by the driver
for that key.
The config keys are OR'ed with any combination of SR_CONF_GET,
SR_CONF_SET and SR_CONF_LIST. These are defined as the high bits
of the uint32_t config key. Clients can OR config keys with
SR_CONF_MASK to strip out these bits. This mask will be kept up to
date if other bits are added to the capabilities list; clients MUST
therefore use SR_CONF_MASK for this.
Some keys don't have capability bits added, such as the informative
device type keys (SR_CONF_MULTIMETER, SR_CONF_OSCILLOSCOPE, ...) and
SR_CONF_CONTINUOUS.
Scan options do not have capabilities bits.
Uwe Hermann
Bert Vermeulen
Soeren Apel
Martin Ling