Re: [PATCH v2] video: backlight: Make use of the helper function dev_err_probe()

From: Daniel Thompson
Date: Fri Sep 17 2021 - 09:15:35 EST


On Fri, Sep 17, 2021 at 08:53:23PM +0800, Cai Huoqing wrote:
> When possible use dev_err_probe help to properly deal with the
> PROBE_DEFER error, the benefit is that DEFER issue will be logged
> in the devices_deferred debugfs file.
> Using dev_err_probe() can reduce code size, and the error value
> gets printed.
>
> Signed-off-by: Cai Huoqing <caihuoqing@xxxxxxxxx>
> ---
> v1->v2: backlight patches are handled in one

This appears to leave a lot of backlight drivers with the same code
pattern that are not updated. As my last e-mail, please can you explain
why you selected these drivers and no others?

I would expect this type of change to be made with the assistance of a
script to automatically help you identify and change the code patterns
you are targetting. This would allow you to update all the backlight
drivers at once.


Daniel.


> drivers/video/backlight/bd6107.c | 16 +++++--------
> drivers/video/backlight/l4f00242t03.c | 34 ++++++++++-----------------
> 2 files changed, 19 insertions(+), 31 deletions(-)
>
> diff --git a/drivers/video/backlight/bd6107.c b/drivers/video/backlight/bd6107.c
> index 515184fbe33a..e21b793302a2 100644
> --- a/drivers/video/backlight/bd6107.c
> +++ b/drivers/video/backlight/bd6107.c
> @@ -120,7 +120,6 @@ static int bd6107_probe(struct i2c_client *client,
> struct backlight_device *backlight;
> struct backlight_properties props;
> struct bd6107 *bd;
> - int ret;
>
> if (pdata == NULL) {
> dev_err(&client->dev, "No platform data\n");
> @@ -148,11 +147,9 @@ static int bd6107_probe(struct i2c_client *client,
> * the reset.
> */
> bd->reset = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_HIGH);
> - if (IS_ERR(bd->reset)) {
> - dev_err(&client->dev, "unable to request reset GPIO\n");
> - ret = PTR_ERR(bd->reset);
> - return ret;
> - }
> + if (IS_ERR(bd->reset))
> + return dev_err_probe(&client->dev, PTR_ERR(bd->reset),
> + "unable to request reset GPIO\n");
>
> memset(&props, 0, sizeof(props));
> props.type = BACKLIGHT_RAW;
> @@ -164,10 +161,9 @@ static int bd6107_probe(struct i2c_client *client,
> dev_name(&client->dev),
> &bd->client->dev, bd,
> &bd6107_backlight_ops, &props);
> - if (IS_ERR(backlight)) {
> - dev_err(&client->dev, "failed to register backlight\n");
> - return PTR_ERR(backlight);
> - }
> + if (IS_ERR(backlight))
> + return dev_err_probe(&client->dev, PTR_ERR(backlight),
> + "failed to register backlight\n");
>
> backlight_update_status(backlight);
> i2c_set_clientdata(client, backlight);
> diff --git a/drivers/video/backlight/l4f00242t03.c b/drivers/video/backlight/l4f00242t03.c
> index 46f97d1c3d21..8d81d4dec3c6 100644
> --- a/drivers/video/backlight/l4f00242t03.c
> +++ b/drivers/video/backlight/l4f00242t03.c
> @@ -179,37 +179,29 @@ static int l4f00242t03_probe(struct spi_device *spi)
> priv->spi = spi;
>
> priv->reset = devm_gpiod_get(&spi->dev, "reset", GPIOD_OUT_HIGH);
> - if (IS_ERR(priv->reset)) {
> - dev_err(&spi->dev,
> - "Unable to get the lcd l4f00242t03 reset gpio.\n");
> - return PTR_ERR(priv->reset);
> - }
> + if (IS_ERR(priv->reset))
> + return dev_err_probe(&spi->dev, PTR_ERR(priv->reset),
> + "Unable to get the lcd l4f00242t03 reset gpio.\n");
> gpiod_set_consumer_name(priv->reset, "lcd l4f00242t03 reset");
>
> priv->enable = devm_gpiod_get(&spi->dev, "enable", GPIOD_OUT_LOW);
> - if (IS_ERR(priv->enable)) {
> - dev_err(&spi->dev,
> - "Unable to get the lcd l4f00242t03 data en gpio.\n");
> - return PTR_ERR(priv->enable);
> - }
> + if (IS_ERR(priv->enable))
> + return dev_err_probe(&spi->dev, PTR_ERR(priv->enable),
> + "Unable to get the lcd l4f00242t03 data en gpio.\n");
> gpiod_set_consumer_name(priv->enable, "lcd l4f00242t03 data enable");
>
> priv->io_reg = devm_regulator_get(&spi->dev, "vdd");
> - if (IS_ERR(priv->io_reg)) {
> - dev_err(&spi->dev, "%s: Unable to get the IO regulator\n",
> - __func__);
> - return PTR_ERR(priv->io_reg);
> - }
> + if (IS_ERR(priv->io_reg))
> + return dev_err_probe(&spi->dev, PTR_ERR(priv->io_reg),
> + "%s: Unable to get the IO regulator\n", __func__);
>
> priv->core_reg = devm_regulator_get(&spi->dev, "vcore");
> - if (IS_ERR(priv->core_reg)) {
> - dev_err(&spi->dev, "%s: Unable to get the core regulator\n",
> - __func__);
> - return PTR_ERR(priv->core_reg);
> - }
> + if (IS_ERR(priv->core_reg))
> + return dev_err_probe(&spi->dev, PTR_ERR(priv->core_reg),
> + "%s: Unable to get the core regulator\n", __func__);
>
> priv->ld = devm_lcd_device_register(&spi->dev, "l4f00242t03", &spi->dev,
> - priv, &l4f_ops);
> + priv, &l4f_ops);
> if (IS_ERR(priv->ld))
> return PTR_ERR(priv->ld);
>
> --
> 2.25.1
>