Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit cdd49a85 authored by Nikolai Kondrashov's avatar Nikolai Kondrashov Committed by Jiri Kosina
Browse files

HID: waltop: comment on tablet modes 



Add a comment on modes supported by Waltop tablets - a knowledge extracted
from the outdated official driver, but not yet used by this driver.

Signed-off-by: default avatarNikolai Kondrashov <spbnick@gmail.com>
Signed-off-by: default avatarJiri Kosina <jkosina@suse.cz>
parent 30311549

drivers/hid/hid-waltop.c

+27 −2
Original line number Diff line number Diff line
@@ -17,13 +17,38 @@ 


#include "hid-ids.h"



/*

 * There exists an official driver on the manufacturer's website, which

 * wasn't submitted to the kernel, for some reason. The official driver

 * doesn't seem to support extra features of some tablets, like wheels.

 *

 * It shows that the feature report ID 2 could be used to control any waltop

 * tablet input mode, switching it between "default", "tablet" and "ink".

 *

 * This driver only uses "default" mode for all the supported tablets. This

 * mode tries to be HID-compatible (not very successfully), but cripples the

 * resolution of some tablets.

 *

 * The "tablet" mode uses some proprietary, yet decipherable protocol, which

 * represents the correct resolution, but is possibly HID-incompatible (i.e.

 * indescribable by a report descriptor).

 *

 * The purpose of the "ink" mode is unknown.

 *

 * The feature reports needed for switching to each mode are these:

 *

 * 02 16 00     default

 * 02 16 01     tablet

 * 02 16 02     ink

 */



/*

 * Original Slim Tablet 5.8 inch report descriptor.

 *

 * All the reports except the report with ID 16 (the stylus) are unused,

 * possibly because the tablet is not configured to, or because they were

 * just copied from a more capable model. The purpose of features described

 * for report ID 2 is unknown.

 * just copied from a more capable model. The full purpose of features

 * described for report ID 2 is unknown.

 *

 * The stylus buttons are described as three bit fields, whereas actually

 * it's an "array", i.e. they're reported as button numbers (1, 2 and 3).