Thanks for reviewing this patch.
On Wed, Mar 08, 2017 at 08:54:47AM +0300, Dan Carpenter wrote:
On Sun, Mar 05, 2017 at 03:22:33AM +0800, Cheah Kok Cheong wrote:
If comedi module is loaded with the following max allowed parameter
[comedi_num_legacy_minors=48], subsequent loading of an auto-configured
device will fail.
Don't set comedi_num_legacy_minors=48, then?
This doesn't seem like the right fix at all. Why only allow one auto
configured board? Why not 5 or 10?
Let me explain, the original intended behaviour is to allow user to
reserve up to 48 minor numbers for legacy devices.
Therefore [sudo modprobe comedi comedi_num_legacy_minors=3]
will allocate minor number 0, 1, 2 for legacy devices.
Subsequent loading of an auto-configured device will use minor number 3.
And the next one number 4 so on and so forth.
Now for the corner case of [comedi_num_legacy_minors=48] which
is supposed to reserve minor number 0 till 47 for legacy devices,
and is supposed to allocate number 48 and so on for auto-configured
devices, does not allocate number 48 anymore after commit
This is due to the changes in comedi_alloc_board_minor().
As to why I chose to limit [comedi_num_legacy_minors=47], is given
in the commit log.
This will allow user to allocate 0 till 46 for legacy devices and
subsequent auto-configured devices will start from 47 and so forth.
I don't think anybody will miss one less number for legacy devices
otherwise there'll be complains earlier on.