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>

1 files changed, 5 insertions, 2 deletions

diff --git a/drivers/atm/fore200e.c b/drivers/atm/fore200e.c
index bdd2719f3f68..bc9e702186dd 100644
--- a/drivers/atm/fore200e.c
+++ b/drivers/atm/fore200e.c
@@ -2643,16 +2643,19 @@ fore200e_init(struct fore200e* fore200e, struct device *parent)
 }
 
 #ifdef CONFIG_SBUS
+static const struct of_device_id fore200e_sba_match[];
 static int __devinit fore200e_sba_probe(struct platform_device *op)
 {
+        const struct of_device_id *match;
         const struct fore200e_bus *bus;
         struct fore200e *fore200e;
         static int index = 0;
         int err;
 
-        if (!op->dev.of_match)
+        match = of_match_device(fore200e_sba_match, &op->dev);
+        if (!match)
                 return -EINVAL;
-        bus = op->dev.of_match->data;
+        bus = match->data;
 
         fore200e = kzalloc(sizeof(struct fore200e), GFP_KERNEL);
         if (!fore200e)