On Fri, Jun 12, 2020 at 8:26 PM Christophe Leroy
<christophe.leroy@xxxxxxxxxx> wrote:
> devm_gpiod_get_index() doesn't return NULL but -ENOENT when the
> requested GPIO doesn't exist, leading to the following messages:
>
> [ 2.742468] gpiod_direction_input: invalid GPIO (errorpointer)
> [ 2.748147] can't set direction for gpio #2: -2
> [ 2.753081] gpiod_direction_input: invalid GPIO (errorpointer)
> [ 2.758724] can't set direction for gpio #3: -2
> [ 2.763666] gpiod_direction_output: invalid GPIO (errorpointer)
> [ 2.769394] can't set direction for gpio #4: -2
> [ 2.774341] gpiod_direction_input: invalid GPIO (errorpointer)
> [ 2.779981] can't set direction for gpio #5: -2
> [ 2.784545] ff000a20.serial: ttyCPM1 at MMIO 0xfff00a20 (irq = 39, base_baud = 8250000) is a CPM UART
>
> Use devm_gpiod_get_index_optional() instead.
>
> At the same time, handle the error case and properly exit
> with an error.
>
> Fixes: 97cbaf2c829b ("tty: serial: cpm_uart: Convert to use GPIO descriptors")
> Cc: stable@xxxxxxxxxxxxxxx
> Cc: Linus Walleij <linus.walleij@xxxxxxxxxx>
> Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
> ---
> v2: Using devm_gpiod_get_index_optional() and exiting if error
Excellent!
Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Yours,
Linus Walleij
