On Sat, Jun 06, 2020 at 07:30:21AM +0000, Christophe Leroy 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 IS_ERR_OR_NULL() to properly check gpiod validity.
Why check for NULL at all?
> 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>
> ---
> drivers/tty/serial/cpm_uart/cpm_uart_core.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/tty/serial/cpm_uart/cpm_uart_core.c b/drivers/tty/serial/cpm_uart/cpm_uart_core.c
> index a04f74d2e854..3cbe24802296 100644
> --- a/drivers/tty/serial/cpm_uart/cpm_uart_core.c
> +++ b/drivers/tty/serial/cpm_uart/cpm_uart_core.c
> @@ -1217,7 +1217,7 @@ static int cpm_uart_init_port(struct device_node *np,
>
> gpiod = devm_gpiod_get_index(dev, NULL, i, GPIOD_ASIS);
>
> - if (gpiod) {
> + if (!IS_ERR_OR_NULL(gpiod)) {
> if (i == GPIO_RTS || i == GPIO_DTR)
> ret = gpiod_direction_output(gpiod, 0);
> else
Johan
