From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E8658C433EF for ; Tue, 15 Feb 2022 02:04:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232081AbiBOCEp (ORCPT ); Mon, 14 Feb 2022 21:04:45 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:48794 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231868AbiBOCEc (ORCPT ); Mon, 14 Feb 2022 21:04:32 -0500 Received: from mail-qt1-x82a.google.com (mail-qt1-x82a.google.com [IPv6:2607:f8b0:4864:20::82a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 178CD246; Mon, 14 Feb 2022 18:04:23 -0800 (PST) Received: by mail-qt1-x82a.google.com with SMTP id b5so17211353qtq.11; Mon, 14 Feb 2022 18:04:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=RY3hPu0eYznmJ1wv60D8yqIoxL5AcD8VFfxgkL4Y/Fo=; b=J1N+91krUrrbs2vmM/dl9OLcuxIrdwW15uOPD4fXjHLn7gT+z7qMpxkI7gP9pz1RjX ONF6sNw7QyBT/gc0yA57fImANC+JXUT5rqdIog7gTMKX/tp5eOQTGWhDaKxWEtQg/hjg rWSQyN+TlSL719hxVuSZCRXKlQOl0FBhJs78VFDbF/IG4enTQDSr38qu/Qoy0cjRzr4w DZhVxvZKFYEjP2sJ+tM53JWYJ3HnR17USJt25+4G6+GJ/sLF+oZHG1gHoRoh9WBmzXwj wGIIUlvvZ9y0azqY0muaCAsrA3fq926RlDIbp6oWj9/xb8e2JXSsC1piCqYTa6VwXrNo GXDA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=RY3hPu0eYznmJ1wv60D8yqIoxL5AcD8VFfxgkL4Y/Fo=; b=u5UXnYDwIwEcsv56Lt8QtuwaHnp2wiVncFH+bjAccIxKOBSavuaHwiEBM5Y6JESz1G xHoj/bIy5vPMIVYxdoK4b7gCrL0ENrlX7rhDYKwSZcIzVjz2pJNCqiP7Ldpes+sm83JR 0kvCgAmXTGzeaEW43D9fAgdqniy5XWGwUDHrwu5Zx7B3EFdq/Aedu8kbSGjhjou7zThj R4wp6/2XORmsSMKJFYE3L6R3RYA/zDuy8B0G+lQlSV1jl8iwHZBOxuQUhWj7PG0G9+GB VJMDRHGAdXd8MOM1Dbk5bAbBju8tJES7hoZl5aflu1fgPsTAXYvhvq4P9atguxxrjF2u 4vtQ== X-Gm-Message-State: AOAM532KOo4g8u6snKiuRDBpNZjgJGHDF5JYDfWkjE/uU4Au/+fgCK1M w7PPRdIHCTtx0jGoqaP9Uf4mx95+z40kjs00vxVl8P9M X-Google-Smtp-Source: ABdhPJyHb+9vNUNBrn9tP3r5axEzGzX4CFU+9PXTEvYEwXnN432HeGIRlNUBhhg6WeJoh29FZkYnpaUsEhXU1oOoWNM= X-Received: by 2002:ac8:5708:: with SMTP id 8mr1288562qtw.668.1644890662050; Mon, 14 Feb 2022 18:04:22 -0800 (PST) MIME-Version: 1.0 References: <20220203143226.4023622-1-benjamin.tissoires@redhat.com> <20220203143226.4023622-11-benjamin.tissoires@redhat.com> In-Reply-To: From: Ping Cheng Date: Mon, 14 Feb 2022 18:04:10 -0800 Message-ID: Subject: Re: [PATCH v2 10/12] HID: input: remove the need for HID_QUIRK_INVERT To: Benjamin Tissoires Cc: Jiri Kosina , Dmitry Torokhov , Jonathan Corbet , =?UTF-8?Q?Ahelenia_Ziemia=C5=84ska?= , Aaron Armstrong Skomra , Jason Gerecke , Peter Hutterer , "open list:HID CORE LAYER" , Linux Doc Mailing List , lkml Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Feb 14, 2022 at 2:23 AM Benjamin Tissoires wrote: > > Hi Ping, > > On Thu, Feb 10, 2022 at 6:44 AM Ping Cheng wrote: > > > > Sorry for the noise. Hit the wrong buttons... > > > > On Wed, Feb 9, 2022 at 9:21 PM Ping Cheng wrote: > > > > > > On Thu, Feb 3, 2022 at 6:33 AM Benjamin Tissoires > > > wrote: > > > > > > > > HID_QUIRK_INVERT is kind of complex to deal with and was bogus. > > > > > > > > Furthermore, it didn't make sense to use a global per struct hid_device > > > > quirk for something dynamic as the current state. > > > > > > > > Store the current tool information in the report itself, and re-order > > > > the processing of the fields to enforce having all the tablet "state" > > > > fields before getting to In Range and other input fields. > > > > > > > > This way, we now have all the information whether a tool is present > > > > or not while processing In Range. > > > > > > > > This new behavior enforces that only one tool gets forwarded to userspace > > > > at the same time, and that if either eraser or invert is set, we enforce > > > > BTN_TOOL_RUBBER. > > > > > > > > Note that the release of the previous tool now happens in its own EV_SYN > > > > report so userspace doesn't get confused by having 2 tools. > > > > > > > > These changes are tested in the following hid-tools regression tests: > > > > https://gitlab.freedesktop.org/libevdev/hid-tools/-/merge_requests/127 > > > > > > > > Signed-off-by: Benjamin Tissoires > > > > > > > > --- > > > > > > > > Changes in v2: > > > > - rework the entire tool switching, this makes the processing > > > > slightly more complex but is better for existing userspace. > > > > --- > > > > drivers/hid/hid-input.c | 98 +++++++++++++++++++++++++++++++++++++---- > > > > include/linux/hid.h | 6 ++- > > > > 2 files changed, 95 insertions(+), 9 deletions(-) > > > > > > > > diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c > > > > index 61d91117f4ae..9f8853640648 100644 > > > > --- a/drivers/hid/hid-input.c > > > > +++ b/drivers/hid/hid-input.c > > > > @@ -63,8 +63,11 @@ static const struct { > > > > * This still leaves us 65535 individual priority values. > > > > */ > > > > static const __u32 hidinput_usages_priorities[] = { > > > > + HID_DG_ERASER, /* Eraser (eraser touching) must always come before tipswitch */ > > > > HID_DG_INVERT, /* Invert must always come before In Range */ > > > > - HID_DG_INRANGE, > > > > + HID_DG_TIPSWITCH, /* Is the tip of the tool touching? */ > > > > + HID_DG_TIPPRESSURE, /* Tip Pressure might emulate tip switch */ > > > > + HID_DG_INRANGE, /* In Range needs to come after the other tool states */ > > > > }; > > > > > > > > #define map_abs(c) hid_map_usage(hidinput, usage, &bit, &max, EV_ABS, (c)) > > > > @@ -1365,9 +1368,38 @@ static void hidinput_handle_scroll(struct hid_usage *usage, > > > > input_event(input, EV_REL, usage->code, hi_res); > > > > } > > > > > > > > +static void hid_report_release_tool(struct hid_report *report, struct input_dev *input, > > > > + unsigned int tool) > > > > +{ > > > > + /* if the given tool is not currently reported, ignore */ > > > > + if (!test_bit(tool, input->key)) > > > > + return; > > > > + > > > > + /* > > > > + * if the given tool was previously set, release it, > > > > + * release any TOUCH and send an EV_SYN > > > > + */ > > > > + input_event(input, EV_KEY, BTN_TOUCH, 0); > > > > + input_event(input, EV_KEY, tool, 0); > > > > Took a while for me to find the right device and setup the proper > > system for the testing. This block missing the serial number: > > > > input_event(input, EV_MSC, MSC_SERIAL, 0); > > > > Without this line, the next tool will not get its serial number. > > I am tempted to simply disregard this request. It has been known for > ages that the evdev values are cached, so if you do not have the value > you need that means that the value has been sent previously (or you > can request it upon start with an ioctl). So in this particular case, > I don't really see the logic in forcing the SERIAL into the TOOL type > when the tool is clearly unrelated to the serial. > > My fear here is that by linking together too many axes, we may enter > in a state where we can not untangle them when needed. I see your point. We indeed added those ioctl's in the X driver to avoid missing the initial states of some of the key events. > > > > > > + input_event(input, EV_SYN, SYN_REPORT, 0); > > > > + > > > > + report->tool = 0; > > > > +} > > > > + > > > > +static void hid_report_set_tool(struct hid_report *report, struct input_dev *input, > > > > + unsigned int new_tool) > > > > +{ > > > > + if (report->tool != new_tool) > > > > + hid_report_release_tool(report, input, report->tool); > > > > + > > > > + input_event(input, EV_KEY, new_tool, 1); > > > > + report->tool = new_tool; > > > > +} > > > > + > > > > void hidinput_hid_event(struct hid_device *hid, struct hid_field *field, struct hid_usage *usage, __s32 value) > > > > { > > > > struct input_dev *input; > > > > + struct hid_report *report = field->report; > > > > unsigned *quirks = &hid->quirks; > > > > > > > > if (!usage->type) > > > > @@ -1418,25 +1450,75 @@ void hidinput_hid_event(struct hid_device *hid, struct hid_field *field, struct > > > > } > > > > > > > > switch (usage->hid) { > > > > + case HID_DG_ERASER: > > > > + report->tool_active |= !!value; > > > > + > > > > + /* > > > > + * if eraser is set, we must enforce BTN_TOOL_RUBBER > > > > + * to accommodate for devices not following the spec. > > > > + */ > > > > + if (value) > > > > + hid_report_set_tool(report, input, BTN_TOOL_RUBBER); > > > > + else if (report->tool != BTN_TOOL_RUBBER) > > > > + /* value is off, tool is not rubber, ignore */ > > > > + return; > > > > + > > > > + /* let hid-input set BTN_TOUCH */ > > > > + break; > > > > + > > > > case HID_DG_INVERT: > > > > - *quirks = value ? (*quirks | HID_QUIRK_INVERT) : (*quirks & ~HID_QUIRK_INVERT); > > > > + report->tool_active |= !!value; > > > > + > > > > + /* > > > > + * If invert is set, we store BTN_TOOL_RUBBER. > > > > + */ > > > > + if (value) > > > > + hid_report_set_tool(report, input, BTN_TOOL_RUBBER); > > > > + else if (!report->tool_active) > > > > + /* tool_active not set means Invert and Eraser are not set */ > > > > + hid_report_release_tool(report, input, BTN_TOOL_RUBBER); > > > > + > > > > + /* no further processing */ > > > > return; > > > > > > > > case HID_DG_INRANGE: > > > > - if (value) { > > > > - input_event(input, usage->type, (*quirks & HID_QUIRK_INVERT) ? BTN_TOOL_RUBBER : usage->code, 1); > > > > - return; > > > > + report->tool_active |= !!value; > > > > + > > > > + if (report->tool_active) { > > > > + /* > > > > + * if tool is not set but is marked as active, > > > > + * assume ours > > > > + */ > > > > + if (!report->tool) > > > > + hid_report_set_tool(report, input, usage->code); > > > > + } else { > > > > + hid_report_release_tool(report, input, usage->code); > > > > } > > > > - input_event(input, usage->type, usage->code, 0); > > > > - input_event(input, usage->type, BTN_TOOL_RUBBER, 0); > > > > + > > > > + /* reset tool_active for the next event */ > > > > + report->tool_active = false; > > > > + > > > > + /* no further processing */ > > > > return; > > > > > > > > + case HID_DG_TIPSWITCH: > > > > + report->tool_active |= !!value; > > > > + > > > > + /* if tool is set to RUBBER we should ignore the current value */ > > > > + if (report->tool == BTN_TOOL_RUBBER) > > > > + return; > > > > This case should return before HID_DG_INVERT is checked since we may > > get TIPSWITCH bit before INVERT. In fact, the device that I tested > > sends the tipswatch bit before the invert bit. So, I alway get a PEN > > in and out before I get ERASER events, when I bring the pen in with > > the side-switch/invert bit pressed. > > > > However, we know not all devices support INVERT. We probably have to > > keep the invert quirk to decide if BTN_TOOL_PEN should be set here or > > wait until HID_DG_INVERT is reached. > > I am under the impression that you completely missed the point of the > patch series. This series re-orders the processing of the events, and > if you look at the very first hunk in this patch, you'll see that the > new processing ensures we treat INVERT and ERASER before TIPSWITCH, no > matter the order of the device. Yeah, I read that part of the code, more than once. But, my evtest gave me an extra set of TOOL_PEN events before TOOL_ERASER. I was confused too. Then I thought maybe the code still relies on the actual order of the usages. Anyway, we've done enough discussion and testing, let's move on. The patchset is: Reviewed-by: Ping Cheng Tested-by: Ping Cheng Thank you for your effort, Benjamin! Ping > So when we process TIPSWITCH here, we are sure that if BTN_TOOL_RUBBER > is set, either INVERT or ERASER is set to 1, whether or not they come > before or after in the report. > > > > > If you are interested in the evtest output, please let me know. I'll > > share it with you offline so we don't abuse this list... > > evtest is the output of the kernel, and it doesn't give me much more > than "it's broken". However, if you can give me the hid-recorder > outputs, I'll be able to reproduce locally and compare the output as I > fix the code. Of course the best would be to add test cases in the > hid-tools repo, but I'll need the hid-recorder anyway to understand > what is failing and to be able to write the tests. > > Cheers, > Benjamin > > > > > Cheers, > > Ping > > > > > > + break; > > > > + > > > > case HID_DG_TIPPRESSURE: > > > > if (*quirks & HID_QUIRK_NOTOUCH) { > > > > int a = field->logical_minimum; > > > > int b = field->logical_maximum; > > > > > > > > - input_event(input, EV_KEY, BTN_TOUCH, value > a + ((b - a) >> 3)); > > > > + if (value > a + ((b - a) >> 3)) { > > > > + input_event(input, EV_KEY, BTN_TOUCH, 1); > > > > + report->tool_active = true; > > > > + } > > > > } > > > > break; > > > > > > > > diff --git a/include/linux/hid.h b/include/linux/hid.h > > > > index eaad0655b05c..feb8df61168f 100644 > > > > --- a/include/linux/hid.h > > > > +++ b/include/linux/hid.h > > > > @@ -347,7 +347,7 @@ struct hid_item { > > > > */ > > > > #define MAX_USBHID_BOOT_QUIRKS 4 > > > > > > > > -#define HID_QUIRK_INVERT BIT(0) > > > > +/* BIT(0) reserved for backward compatibility, was HID_QUIRK_INVERT */ > > > > #define HID_QUIRK_NOTOUCH BIT(1) > > > > #define HID_QUIRK_IGNORE BIT(2) > > > > #define HID_QUIRK_NOGET BIT(3) > > > > @@ -515,6 +515,10 @@ struct hid_report { > > > > unsigned maxfield; /* maximum valid field index */ > > > > unsigned size; /* size of the report (bits) */ > > > > struct hid_device *device; /* associated device */ > > > > + > > > > + /* tool related state */ > > > > + bool tool_active; /* whether the current tool is active */ > > > > + unsigned int tool; /* BTN_TOOL_* */ > > > > }; > > > > > > > > #define HID_MAX_IDS 256 > > > > -- > > > > 2.33.1 > > > > > > >