spi: loopback-test: provide loop_req option.
Provide a module parameter to request internal loop by the SPI master
controller.
This should make loop testing easier without extra HW modification.
For test automation a logic analyzer is recommended for host
controller-independent verification.
An example test rig configuration and procedure:
i.MX6S RIoRBoard Logic Analyzer
-----------------------------------------
(J13 4) GND ------------- GND
(J13 6) CSPI3-CLK ------> PIN 3
(J13 8) CSPI3-MOSI <----- PIN 2
^ - internal loop configured by SPI_LOOP
| or can be user external jamper.
(J13 10) CSPI3-MISO -----> PIN 1
grab some data and decode it:
sigrok-cli -d fx2lafw --time 160000 --config samplerate=10m \
--channels 0-2 -o dump.sr
sigrok-cli -i dump.sr -P spi:mosi=1:clk=2 > result_for_regression_tests
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
1 file changed