Messages in this thread | | | Date | Thu, 18 Nov 2010 09:18:56 -0800 | From | Greg KH <> | Subject | Re: How do I choose an arbitrary minor number for my tty device? |
| |
On Thu, Nov 18, 2010 at 10:56:43AM -0600, Timur Tabi wrote: > Greg KH wrote: > > Why? Again, it doesn't matter, and no other tty driver does it. > > > > Actually you do have control over it, if you really want it, but again, > > don't do that :) > > Because the only way to know which byte channel tty you want is via the byte > channel handle. > > Think of the situation where you have two serial ports on the back of your > computer. One of them is /dev/ttyS0, and the other is /dev/ttyS1. But which > one is which? The only way to find out is try one and see if it works.
No, you can use the /dev/serial/ links to determine exactly which is which depending on the pci id, and other unique identifiers (serial numbers, etc.)
> Now that might be acceptable for serial ports that are fixed physically. But > byte channels handles are completely arbitrary and easily change with even the > slightest re-configuration of the partitions under the hypervisor. I need to > have some way to tell userspace that /dev/ttybc0 is byte channel handle 73.
Then again, just use the /dev/serial/ symlinks that are there for you.
> > Sorry, I can't do code review, or accept code that is not allowed to be > > sent to the public, as, surprise, I'm public :) > > Well, ok. I didn't want to spam the mailing list with something that only you > asked for, but here it is:
Is this somehow not public code? What just changed in the past 15 minutes?
confused,
greg k-h
| |