[PATCH 3.16 041/157] gpio: adnp: Fix testing wrong value in adnp_gpio_direction_input

[Ben Hutchings]

3.16.72-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Axel Lin <axel.lin@xxxxxxxxxx>

commit c5bc6e526d3f217ed2cc3681d256dc4a2af4cc2b upstream.

Current code test wrong value so it does not verify if the written
data is correctly read back. Fix it.
Also make it return -EPERM if read value does not match written bit,
just like it done for adnp_gpio_direction_output().

Fixes: 5e969a401a01 ("gpio: Add Avionic Design N-bit GPIO expander support")
Signed-off-by: Axel Lin <axel.lin@xxxxxxxxxx>
Reviewed-by: Thierry Reding <thierry.reding@xxxxxxxxx>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/gpio/gpio-adnp.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

--- a/drivers/gpio/gpio-adnp.c
+++ b/drivers/gpio/gpio-adnp.c
@@ -140,8 +140,10 @@ static int adnp_gpio_direction_input(str
 	if (err < 0)
 		goto out;
 
-	if (err & BIT(pos))
-		err = -EACCES;
+	if (value & BIT(pos)) {
+		err = -EPERM;
+		goto out;
+	}
 
 	err = 0;