Re: [alsa-devel] [RFC PATCH 2/7] soundwire: add Slave sysfs support

From: Pierre-Louis Bossart
Date: Mon May 06 2019 - 11:00:44 EST



+static struct attribute_group sdw_slave_dev_attr_group = {
+ .attrs = slave_dev_attrs,
+};
+
+const struct attribute_group *sdw_slave_dev_attr_groups[] = {
+ &sdw_slave_dev_attr_group,
+ NULL
+};

ATTRIBUTE_GROUP()?

yes.



+
+int sdw_sysfs_slave_init(struct sdw_slave *slave)
+{
+ struct sdw_slave_sysfs *sysfs;
+ unsigned int src_dpns, sink_dpns, i, j;
+ int err;
+
+ if (slave->sysfs) {
+ dev_err(&slave->dev, "SDW Slave sysfs is already initialized\n");
+ err = -EIO;
+ goto err_ret;
+ }
+
+ sysfs = kzalloc(sizeof(*sysfs), GFP_KERNEL);

Same question as patch 1, why a new device?

yes it's the same open. In this case, the slave devices are defined at a different level so it's also confusing to create a device to represent the slave properties. The code works but I am not sure the initial directions are correct.