Re: [PATCH v10 0/9] Add the I3C subsystem

From: vitor
Date: Thu Nov 15 2018 - 13:04:10 EST


Hi Boris,


On 15/11/18 15:28, Boris Brezillon wrote:
On Thu, 15 Nov 2018 16:01:37 +0100
Wolfram Sang <wsa@xxxxxxxxxxxxx> wrote:

Hi Boris,

What we could do though, is expose I3C devices that do not have a
driver in kernel space, like spidev does.
...

Mark, Wolfram, Arnd, Greg, any opinion?
Is there a benefit for having drivers in userspace? My gut feeling is to
encourage people to write kernel drivers. If this is, for some reason,
not possible for some driver, then we have a use case at hand to test
the then-to-be-developed userspace interface against. Until then, I
personally wouldn't waste effort on designing it without a user in
sight.
I kind of agree with that. Vitor, do you have a use case in mind for
such userspace drivers? I don't think it's worth designing an API for
something we don't need (yet).

My use case is a tool for tests, lets say like the i2c tools. There is other subsystems, some of them mentioned on this thread, that have and ioctl system call or other method to change parameters or send data.


I rise this topic because I really think it worth to define now how this should be design (and for me how to do the things right) to avoid future issues.


Best regards,

Vitor Soares