Add a comment on modes supported by Waltop tablets - a knowledge extracted from the outdated official driver, but not yet used by this driver.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: Nikolai Kondrashov <spbnick@xxxxxxxxx> --- drivers/hid/hid-waltop.c | 29 +++++++++++++++++++++++++++-- 1 files changed, 27 insertions(+), 2 deletions(-) diff --git a/drivers/hid/hid-waltop.c b/drivers/hid/hid-waltop.c index 246160a..6ef9ed6 100644 --- a/drivers/hid/hid-waltop.c +++ b/drivers/hid/hid-waltop.c @@ -18,12 +18,37 @@ #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). -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
