Add support for continuously writing ADC samples to a circular buffer.
CONFIG_ADC_PROFILE_FAST_CONTINUOUS should be defined and an
appropriate sized buffer must be passed to adc_read_all_channels().
BUG=chromium:569994
TEST=Manual on snoball. Verify 'adc' continues to function (single
mode). With pending commit, verify that continuous conversion interrupt
is called at appropriate frequency and values look consistent.
BRANCH=None
Signed-off-by: Shawn Nematbakhsh <shawnn@chromium.org>
Change-Id: I025825d72a698f8f1f4f95a89477df791bd5e67e
Reviewed-on: https://chromium-review.googlesource.com/318505
Commit-Ready: Shawn N <shawnn@chromium.org>
Tested-by: Shawn N <shawnn@chromium.org>
Reviewed-by: Shawn N <shawnn@chromium.org>