[PATCH v3] gpio: adnp: Fix testing wrong value in adnp_gpio_direction_input

[Axel Lin <axel.lin@xxxxxxxxxx>]

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>
---
v3: Add fixes tag
v2: Address Thierry's comment:
Also make it return -EPERM if read value does not match written bit,
just like it done for adnp_gpio_direction_output().

 drivers/gpio/gpio-adnp.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/gpio/gpio-adnp.c b/drivers/gpio/gpio-adnp.c
index 91b90c0cea73..12acdac85820 100644
--- a/drivers/gpio/gpio-adnp.c
+++ b/drivers/gpio/gpio-adnp.c
@@ -132,8 +132,10 @@ static int adnp_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 	if (err < 0)
 		goto out;
 
-	if (err & BIT(pos))
-		err = -EACCES;
+	if (value & BIT(pos)) {
+		err = -EPERM;
+		goto out;
+	}
 
 	err = 0;
 
-- 
2.17.1