On 06-05-19, 11:46, Pierre-Louis Bossart wrote:
On 5/6/19 11:22 AM, Vinod Koul wrote:
On 06-05-19, 17:19, Greg KH wrote:
On Mon, May 06, 2019 at 09:42:35AM -0500, Pierre-Louis Bossart wrote:
+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.
You can just make a subdir for your attributes by using the attribute group name, if a subdirectory is needed just to keep things a bit more organized.
The key here is 'a subdir' which is not the case here. We did discuss this in the initial patches for SoundWire which had sysfs :)
The way MIPI disco spec organized properties, we have dp0 and dpN properties each of them requires to have a subdir of their own and that was the reason why I coded it to be creating a device.
Vinod, the question was not for dp0 and dpN, it's fine to have subdirectories there, but rather why we need separate devices for the master and slave properties.
Slave does not have a separate device. IIRC the properties for Slave are in /sys/bus/soundwire/device/<slave>/...
For master yes we can skip the device creation, it was done for consistency sake of having these properties ties into sys/bus/soundwire/
I don't mind if they are shown up in respective device node (PCI/platform etc) /sys/bus/foo/device/<>
But for creating subdirectories you would need the new dpX devices.
HTH
Do we have a better way to handle this?
Otherwise, you need to mess with having multiple "types" of struct device all associated with the same bus. It is possible, and not that hard, but I don't think you are doing that here.
thnaks,
greg k-h