From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AH8x225QgaurjUlYKEyTtx4eKmHZwT46S1SJE4FjJ2BebW148f0K4Xftbwz/SWeUpdV1KHKZZjlE ARC-Seal: i=1; a=rsa-sha256; t=1516611166; cv=none; d=google.com; s=arc-20160816; b=KHumW0ofuu7nyDXxRwLhuSSURV7PG5T+DfP68ShR1CTPCtrfb3unJ3Bu0RZe9QCOh2 X17iEBoWOc47OAIHNvO+UBQ4DPnXcrLNvp6hwIL61g6ZBJz8chZnVS5QjUHHXVIYoOl/ jFHZuhphcTwlYwbqRYt62FJmeb6u89l9rHieuPRpzlZXUqIjb0ziOhgezlzn16VZtgI5 VjmXMd9ze0vUJUlYfI46jwzcK2h3m7WxhtuQpmmMI6u4jQlEmnaW2teUEy1NGsTsLZU7 mdQDKGZrfWR+dZayi4vb2ULyrrl63NrolqxEFoYh8NUdbv2dXF1keuJRDPS4MBhuVJ+g dYuw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=XIPqckPXET8br8VI8uhr0dA4grWRudkjNM+reCVyHME=; b=nYH/zFVrzPnmkY83yCubmRJ20HdjE61Ded9oiYnAtEs+sQsBhw8atdDVpcNBRz30E3 Ff4wTYfgJJg1PfkNpU7DOq29GIdaffXqFetXzeR0XSwq2k/rz3F9B/FO2a96ENd/+A97 6PS9WTjFC8ma6IayFhf6qVH6xu71O8+j/DOcYOgwOyFWz9+NFxdiad3CqV1g/9ueZkwF 0WPcsdht5RFYBu53IDg8CohoLhd6j5VojqQvMxFnWpnrP/rPRa3Ge+oGdjqFP5v5f5ay qfS7Fk3Z5flkG+RXeBPy//QK3J0lXPnHmykv2F0VA29qPO9HhHGMtuDpVwfP8qBZ8Zmw a88w== ARC-Authentication-Results: i=1; mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.71.90 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org Authentication-Results: mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.71.90 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nir Perry , Masaki Ota , Dmitry Torokhov Subject: [PATCH 4.14 50/89] Input: ALPS - fix multi-touch decoding on SS4 plus touchpads Date: Mon, 22 Jan 2018 09:45:30 +0100 Message-Id: <20180122083959.715282898@linuxfoundation.org> X-Mailer: git-send-email 2.16.0 In-Reply-To: <20180122083954.683903493@linuxfoundation.org> References: <20180122083954.683903493@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1590281873114950328?= X-GMAIL-MSGID: =?utf-8?q?1590282070166258234?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nir Perry commit 4d94e776bd29670f01befa27e12df784fa05fa2e upstream. The fix for handling two-finger scroll (i4a646580f793 - "Input: ALPS - fix two-finger scroll breakage in right side on ALPS touchpad") introduced a minor "typo" that broke decoding of multi-touch events are decoded on some ALPS touchpads. For example, tapping with three-fingers can no longer be used to emulate middle-mouse-button (the kernel doesn't recognize this as the proper event, and doesn't report it correctly to userspace). This affects touchpads that use SS4 "plus" protocol variant, like those found on Dell E7270 & E7470 laptops (tested on E7270). First, probably the code in alps_decode_ss4_v2() for case SS4_PACKET_ID_MULTI used inconsistent indices to "f->mt[]". You can see 0 & 1 are used for the "if" part but 2 & 3 are used for the "else" part. Second, in the previous patch, new macros were introduced to decode X coordinates specific to the SS4 "plus" variant, but the macro to define the maximum X value wasn't changed accordingly. The macros to decode X values for "plus" variant are effectively shifted right by 1 bit, but the max wasn't shifted too. This causes the driver to incorrectly handle "no data" cases, which also interfered with how multi-touch was handled. Fixes: 4a646580f793 ("Input: ALPS - fix two-finger scroll breakage...") Signed-off-by: Nir Perry Reviewed-by: Masaki Ota Signed-off-by: Dmitry Torokhov Signed-off-by: Greg Kroah-Hartman --- drivers/input/mouse/alps.c | 23 +++++++++++++---------- drivers/input/mouse/alps.h | 10 ++++++---- 2 files changed, 19 insertions(+), 14 deletions(-) --- a/drivers/input/mouse/alps.c +++ b/drivers/input/mouse/alps.c @@ -1250,29 +1250,32 @@ static int alps_decode_ss4_v2(struct alp case SS4_PACKET_ID_MULTI: if (priv->flags & ALPS_BUTTONPAD) { if (IS_SS4PLUS_DEV(priv->dev_id)) { - f->mt[0].x = SS4_PLUS_BTL_MF_X_V2(p, 0); - f->mt[1].x = SS4_PLUS_BTL_MF_X_V2(p, 1); + f->mt[2].x = SS4_PLUS_BTL_MF_X_V2(p, 0); + f->mt[3].x = SS4_PLUS_BTL_MF_X_V2(p, 1); + no_data_x = SS4_PLUS_MFPACKET_NO_AX_BL; } else { f->mt[2].x = SS4_BTL_MF_X_V2(p, 0); f->mt[3].x = SS4_BTL_MF_X_V2(p, 1); + no_data_x = SS4_MFPACKET_NO_AX_BL; } + no_data_y = SS4_MFPACKET_NO_AY_BL; f->mt[2].y = SS4_BTL_MF_Y_V2(p, 0); f->mt[3].y = SS4_BTL_MF_Y_V2(p, 1); - no_data_x = SS4_MFPACKET_NO_AX_BL; - no_data_y = SS4_MFPACKET_NO_AY_BL; } else { if (IS_SS4PLUS_DEV(priv->dev_id)) { - f->mt[0].x = SS4_PLUS_STD_MF_X_V2(p, 0); - f->mt[1].x = SS4_PLUS_STD_MF_X_V2(p, 1); + f->mt[2].x = SS4_PLUS_STD_MF_X_V2(p, 0); + f->mt[3].x = SS4_PLUS_STD_MF_X_V2(p, 1); + no_data_x = SS4_PLUS_MFPACKET_NO_AX; } else { - f->mt[0].x = SS4_STD_MF_X_V2(p, 0); - f->mt[1].x = SS4_STD_MF_X_V2(p, 1); + f->mt[2].x = SS4_STD_MF_X_V2(p, 0); + f->mt[3].x = SS4_STD_MF_X_V2(p, 1); + no_data_x = SS4_MFPACKET_NO_AX; } + no_data_y = SS4_MFPACKET_NO_AY; + f->mt[2].y = SS4_STD_MF_Y_V2(p, 0); f->mt[3].y = SS4_STD_MF_Y_V2(p, 1); - no_data_x = SS4_MFPACKET_NO_AX; - no_data_y = SS4_MFPACKET_NO_AY; } f->first_mp = 0; --- a/drivers/input/mouse/alps.h +++ b/drivers/input/mouse/alps.h @@ -141,10 +141,12 @@ enum SS4_PACKET_ID { #define SS4_TS_Z_V2(_b) (s8)(_b[4] & 0x7F) -#define SS4_MFPACKET_NO_AX 8160 /* X-Coordinate value */ -#define SS4_MFPACKET_NO_AY 4080 /* Y-Coordinate value */ -#define SS4_MFPACKET_NO_AX_BL 8176 /* Buttonless X-Coordinate value */ -#define SS4_MFPACKET_NO_AY_BL 4088 /* Buttonless Y-Coordinate value */ +#define SS4_MFPACKET_NO_AX 8160 /* X-Coordinate value */ +#define SS4_MFPACKET_NO_AY 4080 /* Y-Coordinate value */ +#define SS4_MFPACKET_NO_AX_BL 8176 /* Buttonless X-Coord value */ +#define SS4_MFPACKET_NO_AY_BL 4088 /* Buttonless Y-Coord value */ +#define SS4_PLUS_MFPACKET_NO_AX 4080 /* SS4 PLUS, X */ +#define SS4_PLUS_MFPACKET_NO_AX_BL 4088 /* Buttonless SS4 PLUS, X */ /* * enum V7_PACKET_ID - defines the packet type for V7