diff options
| -rw-r--r-- | drivers/hid/hid-core.c | 11 | ||||
| -rw-r--r-- | drivers/hid/hid-input.c | 13 |
2 files changed, 10 insertions, 14 deletions
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index 5a8c01112a2..a9ca93c1192 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -319,7 +319,7 @@ static s32 item_sdata(struct hid_item *item) static int hid_parser_global(struct hid_parser *parser, struct hid_item *item) { - __u32 raw_value; + __s32 raw_value; switch (item->tag) { case HID_GLOBAL_ITEM_TAG_PUSH: @@ -370,10 +370,11 @@ static int hid_parser_global(struct hid_parser *parser, struct hid_item *item) return 0; case HID_GLOBAL_ITEM_TAG_UNIT_EXPONENT: - /* Units exponent negative numbers are given through a - * two's complement. - * See "6.2.2.7 Global Items" for more information. */ - raw_value = item_udata(item); + /* Many devices provide unit exponent as a two's complement + * nibble due to the common misunderstanding of HID + * specification 1.11, 6.2.2.7 Global Items. Attempt to handle + * both this and the standard encoding. */ + raw_value = item_sdata(item); if (!(raw_value & 0xfffffff0)) parser->global.unit_exponent = hid_snto32(raw_value, 4); else diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c index 8741d953dcc..d97f2323af5 100644 --- a/drivers/hid/hid-input.c +++ b/drivers/hid/hid-input.c @@ -192,6 +192,7 @@ static int hidinput_setkeycode(struct input_dev *dev, return -EINVAL; } + /** * hidinput_calc_abs_res - calculate an absolute axis resolution * @field: the HID report field to calculate resolution for @@ -234,23 +235,17 @@ __s32 hidinput_calc_abs_res(const struct hid_field *field, __u16 code) case ABS_MT_TOOL_Y: case ABS_MT_TOUCH_MAJOR: case ABS_MT_TOUCH_MINOR: - if (field->unit & 0xffffff00) /* Not a length */ - return 0; - unit_exponent += hid_snto32(field->unit >> 4, 4) - 1; - switch (field->unit & 0xf) { - case 0x1: /* If centimeters */ + if (field->unit == 0x11) { /* If centimeters */ /* Convert to millimeters */ unit_exponent += 1; - break; - case 0x3: /* If inches */ + } else if (field->unit == 0x13) { /* If inches */ /* Convert to millimeters */ prev = physical_extents; physical_extents *= 254; if (physical_extents < prev) return 0; unit_exponent -= 1; - break; - default: + } else { return 0; } break; |