[PATCH 4.9 213/222] spi: spidev: Fix OF tree warning logic

From: Greg Kroah-Hartman
Date: Fri Nov 22 2019 - 05:49:34 EST

From: Trent Piepho <tpiepho@xxxxxxxxxx>

[ Upstream commit 605b3bec73cbd74b4ac937b580cd0b47d1300484 ]

spidev will make a big fuss if a device tree node binds a device by
using "spidev" as the node's compatible property.

However, the logic for this isn't looking for "spidev" in the
compatible, but rather checking that the device is NOT compatible with
spidev's list of devices.

This causes a false positive if a device not named "rohm,dh2228fv", etc.
binds to spidev, even if a means other than putting "spidev" in the
device tree was used. E.g., the sysfs driver_override attribute.

Signed-off-by: Trent Piepho <tpiepho@xxxxxxxxxx>
Reviewed-by: Jan KundrÃÂt <jan.kundrat@xxxxxxxxx>
Tested-by: Jan KundrÃÂt <jan.kundrat@xxxxxxxxx>
Reviewed-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
drivers/spi/spidev.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/spi/spidev.c b/drivers/spi/spidev.c
index 2e05046f866bd..f4ea286b0121e 100644
--- a/drivers/spi/spidev.c
+++ b/drivers/spi/spidev.c
@@ -751,11 +751,9 @@ static int spidev_probe(struct spi_device *spi)
* compatible string, it is a Linux implementation thing
* rather than a description of the hardware.
- if (spi->dev.of_node && !of_match_device(spidev_dt_ids, &spi->dev)) {
- dev_err(&spi->dev, "buggy DT: spidev listed directly in DT\n");
- WARN_ON(spi->dev.of_node &&
- !of_match_device(spidev_dt_ids, &spi->dev));
- }
+ WARN(spi->dev.of_node &&
+ of_device_is_compatible(spi->dev.of_node, "spidev"),
+ "%pOF: buggy DT: spidev listed directly in DT\n", spi->dev.of_node);