On Do, 2015-03-19 at 14:35 +0100, Michael S. Tsirkin wrote:> On Thu, Mar 19, 2015 at 10:13:10AM +0100, Gerd Hoffmann wrote: > > Hi, > > > > This patch adds a virtio driver for input devices. > > > > Specification: > > https://www.kraxel.org/cgit/virtio-spec/log/?h=virtio-input > > https://www.kraxel.org/virtio/virtio-v1.0-csprd03-virtio-input.html#x1-2640007 > > > OK, I don't know which thread should I use for spec discussions. > Referring to that: > > "See file:///usr/include/linux/input.h." > > Is likely not present on many systems, or might not include > the info you refer to.Dunno what the best way to deal with it is. Link to the version online @ kernel.org instead maybe?> "type, code and value are filled according to the linux input layer > (evdev) interface" > > Which version?Latest. As far I know there never ever have been incompatible changes to the interface, and given this is userspace/kernel abi I don't expect that to happen in the future.> How will non-linux guests know what to implement?There are some docs on the linux input layer and evdev events in Documentation/input/ in the kernel tree. cheers, Gerd
On Thu, Mar 19, 2015 at 03:46:44PM +0100, Gerd Hoffmann wrote:> On Do, 2015-03-19 at 14:35 +0100, Michael S. Tsirkin wrote: > > On Thu, Mar 19, 2015 at 10:13:10AM +0100, Gerd Hoffmann wrote: > > > Hi, > > > > > > This patch adds a virtio driver for input devices. > > > > > > Specification: > > > https://www.kraxel.org/cgit/virtio-spec/log/?h=virtio-input > > > https://www.kraxel.org/virtio/virtio-v1.0-csprd03-virtio-input.html#x1-2640007 > > > > > > OK, I don't know which thread should I use for spec discussions. > > Referring to that: > > > > "See file:///usr/include/linux/input.h." > > > > Is likely not present on many systems, or might not include > > the info you refer to. > > Dunno what the best way to deal with it is. Link to the version online > @ kernel.org instead maybe? > > > "type, code and value are filled according to the linux input layer > > (evdev) interface" > > > > Which version? > > Latest. As far I know there never ever have been incompatible changes > to the interface, and given this is userspace/kernel abi I don't expect > that to happen in the future.More events are added though, are they not? And distros backport rundom subsets. So I worry: what happens e.g. if you migrate between hosts which expose slightly different subsets of events? Might e.g. a button get stuck because button-press event was sent but button-release wasn't?> > How will non-linux guests know what to implement? > > There are some docs on the linux input layer and evdev events in > Documentation/input/ in the kernel tree. > > cheers, > Gerd-- MST
On Thu, Mar 19, 2015 at 03:46:44PM +0100, Gerd Hoffmann wrote:> On Do, 2015-03-19 at 14:35 +0100, Michael S. Tsirkin wrote: > > On Thu, Mar 19, 2015 at 10:13:10AM +0100, Gerd Hoffmann wrote: > > > Hi, > > > > > > This patch adds a virtio driver for input devices. > > > > > > Specification: > > > https://www.kraxel.org/cgit/virtio-spec/log/?h=virtio-input > > > https://www.kraxel.org/virtio/virtio-v1.0-csprd03-virtio-input.html#x1-2640007 > > > > > > OK, I don't know which thread should I use for spec discussions. > > Referring to that: > > > > "See file:///usr/include/linux/input.h." > > > > Is likely not present on many systems, or might not include > > the info you refer to. > > Dunno what the best way to deal with it is. Link to the version online > @ kernel.org instead maybe? > > > "type, code and value are filled according to the linux input layer > > (evdev) interface" > > > > Which version? > > Latest. As far I know there never ever have been incompatible changes > to the interface, and given this is userspace/kernel abi I don't expect > that to happen in the future. > > > How will non-linux guests know what to implement? > > There are some docs on the linux input layer and evdev events in > Documentation/input/ in the kernel tree. > > cheers, > GerdAlso, the spec needs to be rewritten a bit more formally, with conformance clauses separated from freetext description, and linked to from appropriate section. " motion events are send from the device" send->sent -- MST
On 19/03/2015 17:33, Michael S. Tsirkin wrote:> On Thu, Mar 19, 2015 at 03:46:44PM +0100, Gerd Hoffmann wrote: >> Latest. As far I know there never ever have been incompatible changes >> to the interface, and given this is userspace/kernel abi I don't expect >> that to happen in the future. > > More events are added though, are they not? And distros backport rundom > subsets. > So I worry: what happens e.g. if you migrate between hosts which expose > slightly different subsets of events? > Might e.g. a button get stuck because button-press event was > sent but button-release wasn't?I think this is the same as SCSI. You can migrate between hosts which expose slightly different command sets. Paolo