+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.

