Commit ccdd6994 authored Nov 14, 2012 by Benjamin Tissoires Committed by Jiri Kosina Nov 15, 2012

HID: round return value of hidinput_calc_abs_res



hidinput_calc_abs_res should return the closest int in the division
instead of the floor.
On a device with a logical_max of 3008 and a physical_max of 255mm,
previous implementation gave a resolution of 11 instead of 12.
With 11, user-space computes a physical size of 273.5mm and the
round_closest results gives 250.6mm.
The old implementation introduced an error of 2cm in this example.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

parent 37cf6e6f

drivers/hid/hid-input.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -287,7 +287,7 @@ __s32 hidinput_calc_abs_res(const struct hid_field *field, __u16 code)
		}

		/* Calculate resolution */
		return logical_extents / physical_extents;
		return DIV_ROUND_CLOSEST(logical_extents, physical_extents);
		}
		EXPORT_SYMBOL_GPL(hidinput_calc_abs_res);

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