HID: length resolution should be reported units/mm

Input ABI requires reporting resolution on main axes in units per
millimeter, not units per inch, so we need to convert accordingly.

Tested-by: Nikolai Kondrashov <spbnick@gmail.com>
Acked-by: Nikolai Kondrashov <spbnick@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This commit is contained in:
Dmitry Torokhov 2010-12-02 11:49:06 +01:00 committed by Jiri Kosina
parent d65c3768af
commit 83ed79c561
1 changed files with 11 additions and 8 deletions

View File

@ -162,8 +162,8 @@ static int hidinput_setkeycode(struct input_dev *dev,
*
* as seen in the HID specification v1.11 6.2.2.7 Global Items.
*
* Only exponent 1 length units are processed. Centimeters are converted to
* inches. Degrees are converted to radians.
* Only exponent 1 length units are processed. Centimeters and inches are
* converted to millimeters. Degrees are converted to radians.
*/
static __s32 hidinput_calc_abs_res(const struct hid_field *field, __u16 code)
{
@ -184,13 +184,16 @@ static __s32 hidinput_calc_abs_res(const struct hid_field *field, __u16 code)
*/
if (code == ABS_X || code == ABS_Y || code == ABS_Z) {
if (field->unit == 0x11) { /* If centimeters */
/* Convert to inches */
prev = logical_extents;
logical_extents *= 254;
if (logical_extents < prev)
/* Convert to millimeters */
unit_exponent += 1;
} else if (field->unit == 0x13) { /* If inches */
/* Convert to millimeters */
prev = physical_extents;
physical_extents *= 254;
if (physical_extents < prev)
return 0;
unit_exponent += 2;
} else if (field->unit != 0x13) { /* If not inches */
unit_exponent -= 1;
} else {
return 0;
}
} else if (code == ABS_RX || code == ABS_RY || code == ABS_RZ) {