From: Syed Nayyar Waris <syednwaris@xxxxxxxxx>
[ Upstream commit d5ed76adb926a90fada98f518abc1ab6ef07d28f ]
Add lock protection from race conditions to the 104-quad-8 counter
driver for filter clock prescaler code changes. Mutex calls used for
protection.
Signed-off-by: Syed Nayyar Waris <syednwaris@xxxxxxxxx>
Fixes: de65d0556343 ("counter: 104-quad-8: Support Filter Clock Prescaler")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/counter/104-quad-8.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/counter/104-quad-8.c b/drivers/counter/104-quad-8.c
index 9364dc188f8ff..d22cfae1b0198 100644
--- a/drivers/counter/104-quad-8.c
+++ b/drivers/counter/104-quad-8.c
@@ -1365,6 +1365,8 @@ static ssize_t quad8_signal_fck_prescaler_write(struct counter_device *counter,
if (ret)
return ret;
+ mutex_lock(&priv->lock);
+
priv->fck_prescaler[channel_id] = prescaler;
/* Reset Byte Pointer */
@@ -1375,6 +1377,8 @@ static ssize_t quad8_signal_fck_prescaler_write(struct counter_device *counter,
outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP | QUAD8_RLD_PRESET_PSC,
base_offset + 1);
+ mutex_unlock(&priv->lock);
+
return len;
}
--
2.25.1
