From 83ed79c561da20019cb24944f535530d73b2d615 Mon Sep 17 00:00:00 2001 From: Dmitry Torokhov Date: Thu, 2 Dec 2010 11:49:06 +0100 Subject: [PATCH] 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 Acked-by: Nikolai Kondrashov Signed-off-by: Dmitry Torokhov Signed-off-by: Jiri Kosina --- drivers/hid/hid-input.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c index 76e1f64e9765..30af8760174b 100644 --- a/drivers/hid/hid-input.c +++ b/drivers/hid/hid-input.c @@ -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) { -- 2.20.1