From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Tissoires Subject: [PATCH v3 02/13] HID: hid-input: round return value of hidinput_calc_abs_res Date: Wed, 7 Nov 2012 17:37:25 +0100 Message-ID: <1352306256-12180-3-git-send-email-benjamin.tissoires@gmail.com> References: <1352306256-12180-1-git-send-email-benjamin.tissoires@gmail.com> Return-path: In-Reply-To: <1352306256-12180-1-git-send-email-benjamin.tissoires@gmail.com> Sender: linux-kernel-owner@vger.kernel.org To: "benjamin.tissoires" , Dmitry Torokhov , Henrik Rydberg , Jiri Kosina , Stephane Chatty , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-input@vger.kernel.org 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 --- drivers/hid/hid-input.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c index f5b1d57..67044f3 100644 --- a/drivers/hid/hid-input.c +++ b/drivers/hid/hid-input.c @@ -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); -- 1.7.11.7