On Wed, Sep 16, 2015 at 11:47:21PM +0300, Ville Syrjälä wrote: > On Wed, Sep 16, 2015 at 01:09:54PM -0700, Daniel Vetter wrote: > > On Tue, Sep 15, 2015 at 10:03:09AM -0700, Rafael Antognolli wrote: > > > On Tue, Sep 15, 2015 at 07:46:55PM +0300, Ville Syrjälä wrote: > > > > On Tue, Sep 15, 2015 at 07:41:06PM +0300, Ville Syrjälä wrote: > > > > > On Tue, Sep 15, 2015 at 09:34:15AM -0700, Rafael Antognolli wrote: > > > > > > On Tue, Sep 15, 2015 at 10:35:19AM +0300, Ville Syrjälä wrote: > > > > > > > On Mon, Sep 14, 2015 at 04:12:29PM -0700, Rafael Antognolli wrote: > > > > > > > > This is a tentative implementation of a module that allows reading/writing > > > > > > > > arbitrary dpcd registers, following the suggestion from Daniel Vetter. It > > > > > > > > assumes the drm aux helpers were used by the driver. > > > > > > > > > > > > > > > > I tried to follow the i2c-dev implementation as close as possible, but the only > > > > > > > > operations that are provided on the dev node are two different ioctl's, one for > > > > > > > > reading a register and another one for writing it. > > > > > > > > > > > > > > Why would you use ioctls instead of normal read/write syscalls? > > > > > > > > > > > > > > > > > > > For writing, that should work fine, I can easily change that if you > > > > > > prefer. > > > > > > > > > > > > For reading, one has to first tell which register address is going to be > > > > > > read. > > > > > > > > > > seek() > > > > > > > > Sorry typo. Make that lseek(). > > > > > > > Oh, nice, I'll update the patch with this and remove the notifier stuff, > > > thanks! > > > > Well there's also other modes like i2c over aux, and that would be easier > > to support with an ioctl in a uniform way. So not sure how much value > > there is in reusing read/write for i2c ... > > We already have i2c-dev for i2c. So not sure what you're after here. > > i2c is a bit of a mess on the protocol level. Lots of devices do > interesting things with it, so it can't really make do with just > read/write/lseek. Apart from i2c-over-aux, the rest is all about > DPCD access, and for that read/write/lseek is all you ever need. I just noticed that I forgot to cc you guys, but yesterday I sent an updated version of the patch set to this list: http://lists.freedesktop.org/archives/dri-devel/2015-September/090366.html I also don't have a strong opinion about ioctl vs read/write/lseek, but at least my second implementation did get a little cleaner. Thanks, Rafael _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
