[PATCH] Input: ads7846 - fix unaligned access on 7845

From: Dmitry Torokhov
Date: Wed Nov 11 2020 - 20:42:28 EST


req->sample[1] is not naturally aligned at word boundary, and therefore
we should use get_unaligned_be16() when accessing it.

Fixes: 3eac5c7e44f3 ("Input: ads7846 - extend the driver for ads7845 controller support")
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
---

Not tested on hardware, so if somebody has the controller and can verify
that would be great.


drivers/input/touchscreen/ads7846.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/input/touchscreen/ads7846.c b/drivers/input/touchscreen/ads7846.c
index 95e89f675ad5..35d14bc44aff 100644
--- a/drivers/input/touchscreen/ads7846.c
+++ b/drivers/input/touchscreen/ads7846.c
@@ -33,6 +33,7 @@
#include <linux/regulator/consumer.h>
#include <linux/module.h>
#include <asm/irq.h>
+#include <asm/unaligned.h>

/*
* This code has been heavily tested on a Nokia 770, and lightly
@@ -443,7 +444,7 @@ static int ads7845_read12_ser(struct device *dev, unsigned command)

if (status == 0) {
/* BE12 value, then padding */
- status = be16_to_cpu(*((u16 *)&req->sample[1]));
+ status = get_unaligned_be16(&req->sample[1]);
status = status >> 3;
status &= 0x0fff;
}
--
2.29.2.222.g5d2a92d10f8-goog


--
Dmitry