[PATCH AUTOSEL 4.4 43/48] spi: spidev: Fix OF tree warning logic

From: Sasha Levin
Date: Tue Nov 12 2019 - 21:02:56 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 d0e7dfc647cf2..c5f1045561acc 100644
--- a/drivers/spi/spidev.c
+++ b/drivers/spi/spidev.c
@@ -713,11 +713,9 @@ 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);

/* Allocate driver data */
spidev = kzalloc(sizeof(*spidev), GFP_KERNEL);
--
2.20.1