On 7/29/22 08:50, Greg Kroah-Hartman wrote:
> There's no need to special-case the dp0 sysfs attributes, the
> is_visible() callback in the attribute group can handle that for us, so
> add that and add it to the attribute group list making the logic simpler
> overall.
>
> This is a step on the way to moving all of the sysfs attribute handling
> into the default driver core attribute group logic so that the soundwire
> core does not have to do any of it manually.
>
> Cc: Vinod Koul <vkoul@xxxxxxxxxx>
> Cc: Bard Liao <yung-chuan.liao@xxxxxxxxxxxxxxx>
> Cc: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
> Cc: Sanyog Kale <sanyog.r.kale@xxxxxxxxx>
> Cc: alsa-devel@xxxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> ---
> drivers/soundwire/sysfs_slave.c | 18 ++++++++++++------
> 1 file changed, 12 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/soundwire/sysfs_slave.c b/drivers/soundwire/sysfs_slave.c
> index 83e3f6cc3250..3723333a5c2b 100644
> --- a/drivers/soundwire/sysfs_slave.c
> +++ b/drivers/soundwire/sysfs_slave.c
> @@ -174,6 +174,16 @@ static ssize_t words_show(struct device *dev,
> }
> static DEVICE_ATTR_RO(words);
>
> +static umode_t dp0_is_visible(struct kobject *kobj, struct attribute *attr,
> + int n)
> +{
> + struct sdw_slave *slave = dev_to_sdw_dev(kobj_to_dev(kobj));
> +
> + if (slave->prop.dp0_prop)
> + return attr->mode;
> + return 0;
> +}
This changes the results slightly by creating an empty 'dp0' directory
with no attributes inside.
Before:
[root@fedora ~]# cd /sys/bus/soundwire/devices/sdw:3:025d:0714:01
[root@fedora sdw:3:025d:0714:01]# ls dp0
ls: cannot access 'dp0': No such file or directory
After:
[root@fedora sdw:3:025d:0714:01]# ls dp0
> +
> static struct attribute *dp0_attrs[] = {
> &dev_attr_max_word.attr,
> &dev_attr_min_word.attr,
> @@ -190,12 +200,14 @@ static struct attribute *dp0_attrs[] = {
> */
> static const struct attribute_group dp0_group = {
> .attrs = dp0_attrs,
> + .is_visible = dp0_is_visible,
> .name = "dp0",
> };
>
> static const struct attribute_group *slave_groups[] = {
> &slave_attr_group,
> &sdw_slave_dev_attr_group,
> + &dp0_group,
> NULL,
> };
>
> @@ -207,12 +219,6 @@ int sdw_slave_sysfs_init(struct sdw_slave *slave)
> if (ret < 0)
> return ret;
>
> - if (slave->prop.dp0_prop) {
> - ret = devm_device_add_group(&slave->dev, &dp0_group);
> - if (ret < 0)
> - return ret;
> - }
> -
> if (slave->prop.source_ports || slave->prop.sink_ports) {
> ret = sdw_slave_sysfs_dpn_init(slave);
> if (ret < 0)
