From 41ecad2c3cce807abf32bff879cef5dfcacae363 Mon Sep 17 00:00:00 2001 From: David Fries Date: Mon, 13 Jun 2022 00:39:41 -0500 Subject: spi: spidev_test: Warn when the mode is not the requested mode Print a warning if the device mode doesn't match the requested mode. The user doesn't enter the mode in hex so it isn't obvious when setting the mode succeeds that the mode isn't the requested mode. The kernel logs a message, it will be more visible if the test also prints a warning. I was testing --quad, which is unsupported, but doesn't cause the mode request to fail. Signed-off-by: David Fries Link: https://lore.kernel.org/r/YqbNnSGtWHe/GG7w@spacedout.fries.net Signed-off-by: Mark Brown --- tools/spi/spidev_test.c | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'tools/spi') diff --git a/tools/spi/spidev_test.c b/tools/spi/spidev_test.c index 83844f8b862a..b0ca44c70e83 100644 --- a/tools/spi/spidev_test.c +++ b/tools/spi/spidev_test.c @@ -417,6 +417,7 @@ int main(int argc, char *argv[]) { int ret = 0; int fd; + uint32_t request; parse_opts(argc, argv); @@ -430,13 +431,23 @@ int main(int argc, char *argv[]) /* * spi mode */ + /* WR is make a request to assign 'mode' */ + request = mode; ret = ioctl(fd, SPI_IOC_WR_MODE32, &mode); if (ret == -1) pabort("can't set spi mode"); + /* RD is read what mode the device actually is in */ ret = ioctl(fd, SPI_IOC_RD_MODE32, &mode); if (ret == -1) pabort("can't get spi mode"); + /* Drivers can reject some mode bits without returning an error. + * Read the current value to identify what mode it is in, and if it + * differs from the requested mode, warn the user. + */ + if (request != mode) + printf("WARNING device does not support requested mode 0x%x\n", + request); /* * bits per word -- cgit v1.2.3