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authorOleksij Rempel <o.rempel@pengutronix.de>2017-07-14 11:42:46 +0200
committerMark Brown <broonie@kernel.org>2017-07-17 15:27:26 +0100
commitf12a616e0cdee71440b72f7602825db424d37879 (patch)
tree9d32ddb285cd70f4fa991cae35412d6cc0357cf9 /drivers/spi/spi-loopback-test.c
parent5771a8c08880cdca3bfb4a3fc6d309d6bba20877 (diff)
downloadlinux-f12a616e0cdee71440b72f7602825db424d37879.tar.bz2
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>
Diffstat (limited to 'drivers/spi/spi-loopback-test.c')
-rw-r--r--drivers/spi/spi-loopback-test.c16
1 files changed, 16 insertions, 0 deletions
diff --git a/drivers/spi/spi-loopback-test.c b/drivers/spi/spi-loopback-test.c
index 3459965004f8..0d3c56e2526c 100644
--- a/drivers/spi/spi-loopback-test.c
+++ b/drivers/spi/spi-loopback-test.c
@@ -51,6 +51,12 @@ MODULE_PARM_DESC(loopback,
"is checked to match tx_buf after the spi_message " \
"is executed");
+int loop_req;
+module_param(loop_req, int, 0);
+MODULE_PARM_DESC(loop_req,
+ "if set controller will be asked to enable test loop mode. " \
+ "If controller supported it, MISO and MOSI will be connected");
+
/* run only a specific test */
int run_only_test = -1;
module_param(run_only_test, int, 0);
@@ -313,6 +319,16 @@ static int spi_loopback_test_probe(struct spi_device *spi)
{
int ret;
+ if (loop_req) {
+ spi->mode = SPI_LOOP | spi->mode;
+ ret = spi_setup(spi);
+ if (ret) {
+ dev_err(&spi->dev, "SPI setup with SPI_LOOP failed (%d)\n",
+ ret);
+ return ret;
+ }
+ }
+
dev_info(&spi->dev, "Executing spi-loopback-tests\n");
ret = spi_test_run_tests(spi, spi_tests);