From patchwork Fri Oct 26 08:44:18 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Benjamin Tissoires X-Patchwork-Id: 1650281 X-Patchwork-Delegate: jikos@jikos.cz Return-Path: X-Original-To: patchwork-linux-input@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork1.kernel.org (Postfix) with ESMTP id EAD8240135 for ; Fri, 26 Oct 2012 08:48:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757407Ab2JZIpC (ORCPT ); Fri, 26 Oct 2012 04:45:02 -0400 Received: from mail-we0-f174.google.com ([74.125.82.174]:58210 "EHLO mail-we0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757303Ab2JZIoj (ORCPT ); Fri, 26 Oct 2012 04:44:39 -0400 Received: by mail-we0-f174.google.com with SMTP id t9so1288402wey.19 for ; Fri, 26 Oct 2012 01:44:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:subject:date:message-id:x-mailer:in-reply-to:references; bh=4WgKDuUI2o4wWVBmJPxE642fx2wYFW0HEkPLSAP6cw4=; b=otwr6wsn6h/y6PaylEl4vVgJAoSdzvYB9wpLFPbTGYKYbQWShCbbVsvq2sGiHfpXxO Ta1QS/pOSee9TNPLrSd59RD/3771q+dptNzRS1PgdQIwn0h5xYuAEUD0RHF7m/K2rgdw t/rLF8YpRXbb/t6ns6j71M5RqfCZ6z33DWWvfVxW1dDbEG0fU9lMRdhEh99v/LjsT/uF eIZo3O508GZDeULoRr8D9s19WmWRnNKp5YX6oxmoexcgvqfvfuOfUUvDfCllcyM3Smie fxQQ2TAQSY7+p2OdhtTxpxdYaze5/WmcHtLDa9XNUYwSOr8iSiv+KX0QyNnvAECDwSdO xZ8A== Received: by 10.180.87.42 with SMTP id u10mr3612403wiz.0.1351241078348; Fri, 26 Oct 2012 01:44:38 -0700 (PDT) Received: from miniplouf.lan (lan31-8-82-247-176-67.fbx.proxad.net. [82.247.176.67]) by mx.google.com with ESMTPS id dq6sm14151586wib.5.2012.10.26.01.44.37 (version=TLSv1/SSLv3 cipher=OTHER); Fri, 26 Oct 2012 01:44:37 -0700 (PDT) From: Benjamin Tissoires To: "benjamin.tissoires" , Dmitry Torokhov , Henrik Rydberg , Jiri Kosina , Stephane Chatty , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 02/11] HID: core: fix unit exponent parsing Date: Fri, 26 Oct 2012 10:44:18 +0200 Message-Id: <1351241067-9521-3-git-send-email-benjamin.tissoires@gmail.com> X-Mailer: git-send-email 1.7.11.7 In-Reply-To: <1351241067-9521-1-git-send-email-benjamin.tissoires@gmail.com> References: <1351241067-9521-1-git-send-email-benjamin.tissoires@gmail.com> Sender: linux-input-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org HID spec details special values for the HID field unit exponent. Basically, the range [0x8..0xf] correspond to [-8..-1]. Signed-off-by: Benjamin Tissoires --- drivers/hid/hid-core.c | 10 +++++++++- drivers/hid/hid-input.c | 19 +++++++++++++------ 2 files changed, 22 insertions(+), 7 deletions(-) diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index 9904776..6bde6e4 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -315,6 +315,7 @@ static s32 item_sdata(struct hid_item *item) static int hid_parser_global(struct hid_parser *parser, struct hid_item *item) { + __u32 raw_value; switch (item->tag) { case HID_GLOBAL_ITEM_TAG_PUSH: @@ -365,7 +366,14 @@ static int hid_parser_global(struct hid_parser *parser, struct hid_item *item) return 0; case HID_GLOBAL_ITEM_TAG_UNIT_EXPONENT: - parser->global.unit_exponent = item_sdata(item); + /* Units exponent negative numbers are given through a special + * table. + * See "6.2.2.7 Global Items" for more information. */ + raw_value = item_udata(item); + if ((raw_value >> 3) == 1) + parser->global.unit_exponent = raw_value - 16; + else + parser->global.unit_exponent = raw_value; return 0; case HID_GLOBAL_ITEM_TAG_UNIT: diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c index 1b0adc3..fc9f2b5 100644 --- a/drivers/hid/hid-input.c +++ b/drivers/hid/hid-input.c @@ -215,7 +215,7 @@ __s32 hidinput_calc_abs_res(const struct hid_field *field, __u16 code) field->logical_minimum; __s32 physical_extents = field->physical_maximum - field->physical_minimum; - __s32 prev; + __s32 prev, tmp_exponent; /* Check if the extents are sane */ if (logical_extents <= 0 || physical_extents <= 0) @@ -235,17 +235,24 @@ __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 == 0x11) { /* If centimeters */ + if (field->unit & 0xffffff00) /* Not a length */ + return 0; + tmp_exponent = field->unit >> 4; + if ((tmp_exponent >> 3) == 1) + tmp_exponent -= 16; + switch (field->unit & 0xf) { + case 0x1: /* If centimeters */ /* Convert to millimeters */ - unit_exponent += 1; - } else if (field->unit == 0x13) { /* If inches */ + unit_exponent += tmp_exponent; + break; + case 0x3: /* If inches */ /* Convert to millimeters */ prev = physical_extents; physical_extents *= 254; if (physical_extents < prev) return 0; - unit_exponent -= 1; - } else { + unit_exponent += tmp_exponent - 2; + default: return 0; } break;