On 12/15/2010 05:26 AM, Henrik Rydberg wrote: >>> Ping has touched upon this subject as well, from the pen & touch perspective. >>> Generally, some ABS axes are actually enumerations, for which we have no >>> direct abstraction. If we had a way to declare the used values for such >>> enumerations, it would resolve these and possibly other issues. > >> I think that presence of pen/touch can be detected by having >> BTN_TOOL_PEN and BTN_TOOL_FINGER. However in this case the tool is >> finger, so I do not think we should introduce BTN_TOOL_ENVELOPE. Maybe >> this is another case where we should employ the proposed device flags? > > Yes. Having something like INPUT_QUIRK_SEMI_MT might be enough, and we could > drop the whole MT_TOOL_ENVELOPE circus. Chase, Peter, Chris, would you be > comfortable with such a solution? That sounds like a good solution to me. I believe it would resolve all the issues I had. As I attempted to write up more documentation, I thought of the following. What do you think? With regards to partial MT devices, if the device provides a single valued property, such as pressure and tool type for synaptics, it may only be provided through the traditional property semantics, i.e. ABS_PRESSURE and BTN_TOOL_*. If the device provides multiple values for a property, then ABS_MT_* types may be used as well to provide up to two values, though the client should understand there's no direct correlation between the slot's coordinates and the property. I could see this being used to provide info on multiple tool types or a high and low pressure. Enforcing the above behaviour provides even more information about the capabilities of the device based solely on the evdev codes published. Thanks, -- Chase -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
