unstable /sys interface from hmon

[Daniel Walker]

Hi,

Cisco recently upgraded to kernel 4.4.. We have applications which use the /sys interfaces for some hmon drivers.
We found that the following patches,

https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=bab2243ce1897865e31ea6d59b0478391f51812b
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=c3b7cddc70075d525db6b3068d8b2b9158eedc84

Altered the interface as seen from userspace. These patches changed the paths in the following way,

Before,
/sys/bus/i2c/devices/14-0050/

After,
/sys/bus/i2c/devices/14-0050/hwmon/hwmon7

My impression was that /sys was suppose to be stable, and debugfs was unstable. I'm not sure what the current guidelines are
for this, but we would request that hmon drivers maintain a stable interface from /sys. This change has cause upgrade issues
for us which we would like to avoid in the future.

A patch to add in a compatibility layer would be welcome.

Daniel