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: 5e969a401a ("gpio: Add Avionic Design N-bit GPIO expander support")
Change-Id: I5bfca7b948cdc66127219e7bcdcbc4b0cd83ae76
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Reviewed-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>