Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755020AbdDJPgo (ORCPT ); Mon, 10 Apr 2017 11:36:44 -0400 Received: from mx2.suse.de ([195.135.220.15]:38054 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754815AbdDJPfC (ORCPT ); Mon, 10 Apr 2017 11:35:02 -0400 X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "References" From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Raphael Assenat , Dmitry Torokhov , Oliver Neukum , Jiri Slaby Subject: [PATCH 3.12 138/142] Input: joydev - do not report stale values on first open Date: Mon, 10 Apr 2017 17:33:39 +0200 Message-Id: <0548eea77eadb446a47a0c85be0dff09ff2e4b2e.1491838390.git.jslaby@suse.cz> X-Mailer: git-send-email 2.12.2 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2773 Lines: 82 From: Raphael Assenat 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit 45536d373a21d441bd488f618b6e3e9bfae839f3 upstream. Postpone axis initialization to the first open instead of doing it in joydev_connect. This is to make sure the generated startup events are representative of the current joystick state rather than what it was when joydev_connect() was called, potentially much earlier. Once the first user is connected to joydev node we'll be updating joydev->abs[] values and subsequent clients will be getting correct initial states as well. This solves issues with joystick driven menus that start scrolling up each time they are started, until the user moves the joystick to generate events. In emulator menu setups where the menu program is restarted every time the game exits, the repeated need to move the joystick to stop the unintended scrolling gets old rather quickly... Signed-off-by: Raphael Assenat Signed-off-by: Dmitry Torokhov Cc: Oliver Neukum Signed-off-by: Jiri Slaby --- drivers/input/joydev.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) diff --git a/drivers/input/joydev.c b/drivers/input/joydev.c index f362883c94e3..3736c1759524 100644 --- a/drivers/input/joydev.c +++ b/drivers/input/joydev.c @@ -188,6 +188,17 @@ static void joydev_detach_client(struct joydev *joydev, synchronize_rcu(); } +static void joydev_refresh_state(struct joydev *joydev) +{ + struct input_dev *dev = joydev->handle.dev; + int i, val; + + for (i = 0; i < joydev->nabs; i++) { + val = input_abs_get_val(dev, joydev->abspam[i]); + joydev->abs[i] = joydev_correct(val, &joydev->corr[i]); + } +} + static int joydev_open_device(struct joydev *joydev) { int retval; @@ -202,6 +213,8 @@ static int joydev_open_device(struct joydev *joydev) retval = input_open_device(&joydev->handle); if (retval) joydev->open--; + else + joydev_refresh_state(joydev); } mutex_unlock(&joydev->mutex); @@ -823,7 +836,6 @@ static int joydev_connect(struct input_handler *handler, struct input_dev *dev, j = joydev->abspam[i]; if (input_abs_get_max(dev, j) == input_abs_get_min(dev, j)) { joydev->corr[i].type = JS_CORR_NONE; - joydev->abs[i] = input_abs_get_val(dev, j); continue; } joydev->corr[i].type = JS_CORR_BROKEN; @@ -838,10 +850,6 @@ static int joydev_connect(struct input_handler *handler, struct input_dev *dev, if (t) { joydev->corr[i].coef[2] = (1 << 29) / t; joydev->corr[i].coef[3] = (1 << 29) / t; - - joydev->abs[i] = - joydev_correct(input_abs_get_val(dev, j), - joydev->corr + i); } } -- 2.12.2