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 ACC34C433FE for ; Mon, 28 Nov 2022 18:15:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232267AbiK1SPl (ORCPT ); Mon, 28 Nov 2022 13:15:41 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50204 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231206AbiK1SPJ (ORCPT ); Mon, 28 Nov 2022 13:15:09 -0500 Received: from mail-pf1-x42f.google.com (mail-pf1-x42f.google.com [IPv6:2607:f8b0:4864:20::42f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DA09D27FE8; Mon, 28 Nov 2022 09:57:55 -0800 (PST) Received: by mail-pf1-x42f.google.com with SMTP id a16so10829665pfg.4; Mon, 28 Nov 2022 09:57:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=mGYHL/uLgxqY/hmbsLGPFlswmvjTtEjEvO53BHY2clM=; b=Zy4YtCCsFe4vW1pmTteWWz0sKbQYRshwXXTwcDbsVKAHVpn5xH3D2+coKtOYIK8/hg 1GMzs7P9QEQg0T50pJCy4qDYPVvUJhro+ZELoBeIx+LNGnhik8ADdnHeFzal94rFrvyF dWPfheYlBdXGxcnpBXFDeSNc1LfpVtqSRrjtTeDlC3LalrEbMxRZvAXkE3zAKmnzhZyR mLj0Yu9n6lB5ahGqa3HSr5Mg7U9dxEzDQYkhnKCpWpdz/McqM/z5DhMfH53rXf0+HoHe lGv+LVrTqyAp106UMnsAmZxndha3W/gy+4r9rOJjvpqhiiMp4BIlwMjqRhgnIbbZzpmd 9XRA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=mGYHL/uLgxqY/hmbsLGPFlswmvjTtEjEvO53BHY2clM=; b=K7InDGCnuoGX8ejefDNknhQTNu9+GyWeJmN9+RFydR8RFuruUzFkPWayX8lmLfDMk/ 2zTGYzYaYNZ7WM3bU/iZzcY5Dpyt3VINdmLJOLgNKBaypacM7XvGERdwBpY93YPhrStM eLfqAmZb1HsHbhUOnuT4bbbW6sU9I5t8PMHeqwoUpc3gElER6iAi6U/HOu2maRH8oTTT DwmLtAiZ1g61/mkFR3A65X3FRTPz3szMngPxYQagsCJsqlVCXrTsnLN4PF4wsx+X7CDQ H/rjb2jgiZurH7LngLtqteUCkutA4921lf/RHftefcnMEMhnLke1oTgjM1msS/8JV40Y LOqg== X-Gm-Message-State: ANoB5pnLWW5Iq0DbokimcT+MzIPmcmsqEqQGwQNrxpZBvZoN64V4Bqh3 TD/0kNMlNMCtOkU48p8KSHLhBkJbFEM= X-Google-Smtp-Source: AA0mqf5cx+Ejhggzq5N2LBS9KPJdQVVaseeYe904vd+bwBKZ1ACXB9hXyj5x4Xyn6rP4viJos42Q7g== X-Received: by 2002:a05:6a00:198d:b0:569:92fa:cbbc with SMTP id d13-20020a056a00198d00b0056992facbbcmr33654896pfl.77.1669658275045; Mon, 28 Nov 2022 09:57:55 -0800 (PST) Received: from google.com ([2620:15c:9d:2:fd7c:c075:f9ff:46c4]) by smtp.gmail.com with ESMTPSA id b4-20020a62cf04000000b0057255b7c8easm8385819pfg.33.2022.11.28.09.57.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 28 Nov 2022 09:57:54 -0800 (PST) Date: Mon, 28 Nov 2022 09:57:51 -0800 From: Dmitry Torokhov To: Eirin Nya Cc: linux-input@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH V2 3/3] Input: elantech - Fix incorrectly halved touchpad range on ELAN v3 touchpads Message-ID: References: <20221014111533.908-1-nyanpasu256@gmail.com> <20221014111533.908-4-nyanpasu256@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221014111533.908-4-nyanpasu256@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 14, 2022 at 04:15:33AM -0700, Eirin Nya wrote: > On Linux 5.19.10, on my laptop (Dell Inspiron 15R SE 7520) with an Elan > v3 touchpad (dmesg says "with firmware version 0x450f02"), the reported > size of my touchpad (in userspace by calling mtdev_configure() and > libevdev_get_abs_maximum(), in kernel space > elantech_device_info::x_max/y_max, either way 1470 by 700) is half that > of the actual touch range (2940 by 1400), and the upper half of my > touchpad reports negative values. As a result, with the Synaptics or > libinput X11 driver set to edge scrolling mode, the entire right half of > my touchpad has x-values past evdev's reported maximum size, and acts as > a giant scrollbar! > > The problem is that elantech_setup_ps2() -> elantech_set_absolute_mode() > sets up absolute mode and doubles the hardware resolution (doubling the > hardware's maximum reported x/y coordinates and its response to > ETP_FW_ID_QUERY), *after* elantech_query_info() fetches the touchpad > coordinate system size using ETP_FW_ID_QUERY, which gets cached and > reported to userspace through ioctl(fd, EVIOCGABS(ABS_X/Y), ...). So the > touchpad size reported to userspace (and used to subtract vertical > coordinates from) is half the maximum position of actual touches. > > This patch splits out a function elantech_query_range_v3() which fetches > *only* ETP_FW_ID_QUERY (touchpad size), and calls it a second time if > elantech_set_absolute_mode() enables double-size mode. This means the > first call is redundant and wasted if a second call occurs, but this > minimizes the need to restructure the driver. If the setting is indeed double resolution, can we simply multiply x_max and y_max by 2 instead of re-querying it? Also let's try adding one of Elan engineers for their take in this. Phoenix, do you have any suggestions please? > > Link: https://lore.kernel.org/linux-input/CAL57YxZNutUVxBtvbVWKMw-V2kqeVB5kTQ5BFdJmN=mdPq8Q8Q@mail.gmail.com/ > Link: https://lore.kernel.org/linux-input/20221008093437.72d0f6b0@dell-void.nyanpasu256.gmail.com.beta.tailscale.net/ > Fixes: 37548659bb22 ("Input: elantech - query the min/max information beforehand too") > Signed-off-by: Eirin Nya > --- > > Notes: > Should we move (elantech_set_absolute_mode -> > elantech_write_reg(...0x0b or 0x01)) *earlier* into elantech_query_info() > before "query range information"? See discussion at > https://lore.kernel.org/linux-input/20221008093437.72d0f6b0@dell-void.nyanpasu256.gmail.com.beta.tailscale.net/ > > drivers/input/mouse/elantech.c | 30 ++++++++++++++++++++++++++---- > 1 file changed, 26 insertions(+), 4 deletions(-) > > diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c > index 263779c031..a2176f0fd3 100644 > --- a/drivers/input/mouse/elantech.c > +++ b/drivers/input/mouse/elantech.c > @@ -1006,6 +1006,9 @@ static void elantech_set_rate_restore_reg_07(struct psmouse *psmouse, > psmouse_err(psmouse, "restoring reg_07 failed\n"); > } > > +static int elantech_query_range_v3(struct psmouse *psmouse, > + struct elantech_device_info *info); > + > /* > * Put the touchpad into absolute mode > */ > @@ -1047,6 +1050,14 @@ static int elantech_set_absolute_mode(struct psmouse *psmouse) > if (elantech_write_reg(psmouse, 0x10, etd->reg_10)) > rc = -1; > > + /* > + * If we boost hardware resolution, we have to re-query > + * info->x_max and y_max. > + */ > + if (etd->info.set_hw_resolution) > + if (elantech_query_range_v3(psmouse, &etd->info)) > + rc = -1; > + > break; > > case 4: > @@ -1671,6 +1682,20 @@ static int elantech_set_properties(struct elantech_device_info *info) > return 0; > } > > +static int elantech_query_range_v3(struct psmouse *psmouse, > + struct elantech_device_info *info) > +{ > + unsigned char param[3]; > + > + if (info->send_cmd(psmouse, ETP_FW_ID_QUERY, param)) > + return -EINVAL; > + > + info->x_max = (0x0f & param[0]) << 8 | param[1]; > + info->y_max = (0xf0 & param[0]) << 4 | param[2]; > + > + return 0; > +} > + > static int elantech_query_info(struct psmouse *psmouse, > struct elantech_device_info *info) > { > @@ -1826,11 +1851,8 @@ static int elantech_query_info(struct psmouse *psmouse, > break; > > case 3: > - if (info->send_cmd(psmouse, ETP_FW_ID_QUERY, param)) > + if (elantech_query_range_v3(psmouse, info)) > return -EINVAL; > - > - info->x_max = (0x0f & param[0]) << 8 | param[1]; > - info->y_max = (0xf0 & param[0]) << 4 | param[2]; > break; > > case 4: > -- > 2.38.0 > Thanks. -- Dmitry