Re: [PATCH v3 1/3] drm/bridge: parade-ps8640: Improve logging at probing

From: Stephen Boyd
Date: Tue Sep 14 2021 - 20:27:21 EST


Quoting Philip Chen (2021-09-14 16:28:43)
> Use dev_err_probe() to add logs for error cases at probing time.
>
> Signed-off-by: Philip Chen <philipchen@xxxxxxxxxxxx>
> ---
>

Can you use a cover-letter for more than one patch series?

> (no changes since v1)
>
> drivers/gpu/drm/bridge/parade-ps8640.c | 22 ++++++++++++++--------
> 1 file changed, 14 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/parade-ps8640.c b/drivers/gpu/drm/bridge/parade-ps8640.c
> index 685e9c38b2db..e340af381e05 100644
> --- a/drivers/gpu/drm/bridge/parade-ps8640.c
> +++ b/drivers/gpu/drm/bridge/parade-ps8640.c
> @@ -332,8 +332,10 @@ static int ps8640_probe(struct i2c_client *client)
> return -ENODEV;
>
> ps_bridge->panel_bridge = devm_drm_panel_bridge_add(dev, panel);
> - if (IS_ERR(ps_bridge->panel_bridge))
> - return PTR_ERR(ps_bridge->panel_bridge);
> + if (IS_ERR(ps_bridge->panel_bridge)) {
> + return dev_err_probe(dev, PTR_ERR(ps_bridge->panel_bridge),
> + "Error creating bridge device\n");

>From what I can tell it never returns -EPROBE_DEFER? So this isn't
useful.

> + }
>
> ps_bridge->supplies[0].supply = "vdd33";
> ps_bridge->supplies[1].supply = "vdd12";
> @@ -344,16 +346,20 @@ static int ps8640_probe(struct i2c_client *client)
>
> ps_bridge->gpio_powerdown = devm_gpiod_get(&client->dev, "powerdown",
> GPIOD_OUT_HIGH);
> - if (IS_ERR(ps_bridge->gpio_powerdown))
> - return PTR_ERR(ps_bridge->gpio_powerdown);
> + if (IS_ERR(ps_bridge->gpio_powerdown)) {
> + return dev_err_probe(dev, PTR_ERR(ps_bridge->gpio_powerdown),
> + "Error getting gpio_powerdown\n");

This looks ok, except we don't want braces on single statement ifs.

> + }
>
> /*
> * Assert the reset to avoid the bridge being initialized prematurely
> */
> ps_bridge->gpio_reset = devm_gpiod_get(&client->dev, "reset",
> GPIOD_OUT_HIGH);
> - if (IS_ERR(ps_bridge->gpio_reset))
> - return PTR_ERR(ps_bridge->gpio_reset);
> + if (IS_ERR(ps_bridge->gpio_reset)) {
> + return dev_err_probe(dev, PTR_ERR(ps_bridge->gpio_reset),
> + "Error getting gpio_reset\n");

Same.

> + }
>
> ps_bridge->bridge.funcs = &ps8640_bridge_funcs;
> ps_bridge->bridge.of_node = dev->of_node;