Re: [PATCH 2/2] ucsi_ccg: Don't show non-functional attributes

[Heikki Krogerus <heikki.krogerus@linux.intel.com>]

On Thu, Feb 20, 2025 at 11:40:04PM -0600, Mario Limonciello wrote:
> From: Mario Limonciello <mario.limonciello@amd.com>
> 
> If no fw_build is recognized for the controller there is no point to
> exposing the `do_flash` attribute.
> 
> Add an is_visible callback to the attribute group and check for that
> fw_build member to hide when not applicable.
> 
> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>

Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>

> ---
>  drivers/usb/typec/ucsi/ucsi_ccg.c | 25 +++++++++++++++++++------
>  1 file changed, 19 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/usb/typec/ucsi/ucsi_ccg.c b/drivers/usb/typec/ucsi/ucsi_ccg.c
> index 663aca9421410..801a66efa9820 100644
> --- a/drivers/usb/typec/ucsi/ucsi_ccg.c
> +++ b/drivers/usb/typec/ucsi/ucsi_ccg.c
> @@ -1390,22 +1390,35 @@ static ssize_t do_flash_store(struct device *dev,
>  	if (!flash)
>  		return n;
>  
> -	if (uc->fw_build == 0x0) {
> -		dev_err(dev, "fail to flash FW due to missing FW build info\n");
> -		return -EINVAL;
> -	}
> -
>  	schedule_work(&uc->work);
>  	return n;
>  }
>  
> +static umode_t ucsi_ccg_attrs_is_visible(struct kobject *kobj, struct attribute *attr, int idx)
> +{
> +	struct device *dev = kobj_to_dev(kobj);
> +	struct ucsi_ccg *uc = i2c_get_clientdata(to_i2c_client(dev));
> +
> +	if (!uc->fw_build)
> +		return 0;
> +
> +	return attr->mode;
> +}
> +
>  static DEVICE_ATTR_WO(do_flash);
>  
>  static struct attribute *ucsi_ccg_attrs[] = {
>  	&dev_attr_do_flash.attr,
>  	NULL,
>  };
> -ATTRIBUTE_GROUPS(ucsi_ccg);
> +static struct attribute_group ucsi_ccg_attr_group = {
> +	.attrs = ucsi_ccg_attrs,
> +	.is_visible = ucsi_ccg_attrs_is_visible,
> +};
> +static const struct attribute_group *ucsi_ccg_groups[] = {
> +	&ucsi_ccg_attr_group,
> +	NULL,
> +};
>  
>  static int ucsi_ccg_probe(struct i2c_client *client)
>  {
> -- 
> 2.43.0

-- 
heikki