aboutsummaryrefslogtreecommitdiff
path: root/tools/perf/scripts/python/stackcollapse.py
diff options
context:
space:
mode:
authorStephan Olbrich <[email protected]>2016-02-14 11:04:28 +0100
committerMark Brown <[email protected]>2016-02-15 20:45:19 +0000
commitb4e2adef62062cf716d1c81adc12ad6def516f72 (patch)
treec18a2f0cfccffb6f23757cb9552e9d4e9fe60d54 /tools/perf/scripts/python/stackcollapse.py
parentf29ab1845f3e2684ba1c6de6c3bd5198e4b1459c (diff)
spi: bcm2835aux: set up spi-mode before asserting cs-gpio
When using reverse polarity for clock (spi-cpol) on a device the clock line gets altered after chip-select has been asserted resulting in an additional clock beat, which confuses hardware. This happens due to the fact, the the hardware was initialized and reset at the begin and end of each transfer which results in default state for all lines except chip-select which is handled by the spi-subsystem as gpio-cs is used. To avoid this situation this patch moves the setup of polarity (spi-cpol and spi-cpha) outside of the chip-select into prepare_message, which is run prior to asserting chip-select. Signed-off-by: Stephan Olbrich <[email protected]> Reviewed-by: Martin Sperl <[email protected]> Tested-by: Martin Sperl <[email protected]> Reviewed-by: Eric Anholt <[email protected]> Signed-off-by: Mark Brown <[email protected]>
Diffstat (limited to 'tools/perf/scripts/python/stackcollapse.py')
0 files changed, 0 insertions, 0 deletions