drivercore: revert addition of of_match to struct device
Commit b826291c, "drivercore/dt: add a match table pointer to struct
device" added an of_match pointer to struct device to cache the
of_match_table entry discovered at driver match time. This was unsafe
because matching is not an atomic operation with probing a driver. If
two or more drivers are attempted to be matched to a driver at the
same time, then the cached matching entry pointer could get
overwritten.
This patch reverts the of_match cache pointer and reworks all users to
call of_match_device() directly instead.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
diff --git a/drivers/char/hw_random/n2-drv.c b/drivers/char/hw_random/n2-drv.c
index 43ac619..ac6739e 100644
--- a/drivers/char/hw_random/n2-drv.c
+++ b/drivers/char/hw_random/n2-drv.c
@@ -619,15 +619,18 @@
pr_info("%s", version);
}
+static const struct of_device_id n2rng_match[];
static int __devinit n2rng_probe(struct platform_device *op)
{
+ const struct of_device_id *match;
int victoria_falls;
int err = -ENOMEM;
struct n2rng *np;
- if (!op->dev.of_match)
+ match = of_match_device(n2rng_match, &op->dev);
+ if (!match)
return -EINVAL;
- victoria_falls = (op->dev.of_match->data != NULL);
+ victoria_falls = (match->data != NULL);
n2rng_driver_version();
np = kzalloc(sizeof(*np), GFP_KERNEL);
