From patchwork Thu May 15 11:22:34 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 4181611 Return-Path: X-Original-To: patchwork-linux-acpi@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 8C14A9F387 for ; Thu, 15 May 2014 11:23:03 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 8CF712037E for ; Thu, 15 May 2014 11:23:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2261920253 for ; Thu, 15 May 2014 11:23:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751845AbaEOLW7 (ORCPT ); Thu, 15 May 2014 07:22:59 -0400 Received: from mx1.redhat.com ([209.132.183.28]:56442 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752616AbaEOLW5 (ORCPT ); Thu, 15 May 2014 07:22:57 -0400 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id s4FBMikM006017 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 15 May 2014 07:22:44 -0400 Received: from shalem.localdomain.com (vpn1-5-217.ams2.redhat.com [10.36.5.217]) by int-mx11.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id s4FBMb2q024019; Thu, 15 May 2014 07:22:42 -0400 From: Hans de Goede To: Lee Chun-Yi , Aaron Lu Cc: Zhang Rui , "Rafael J. Wysocki" , Len Brown , Matthew Garrett , Massimiliano , linux-acpi@vger.kernel.org, platform-driver-x86@vger.kernel.org, Hans de Goede Subject: [PATCH 2/4] acpi-video: Add an acpi_video_unregister_backlight function Date: Thu, 15 May 2014 13:22:34 +0200 Message-Id: <1400152956-9053-3-git-send-email-hdegoede@redhat.com> In-Reply-To: <1400152956-9053-1-git-send-email-hdegoede@redhat.com> References: <1400152956-9053-1-git-send-email-hdegoede@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.24 Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org X-Spam-Status: No, score=-7.5 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Add an acpi_video_unregister_backlight function, which only unregisters the backlight device, and leaves the acpi_notifier in place. Some acpi_vendor driver need this as they don't want the acpi_video# backlight device, but do need the acpi-video driver for hotkey handling. Chances are that this new acpi_video_unregister_backlight() is actually what existing acpi_vendor drivers have wanted all along. Currently acpi_vendor drivers which want to disable the acpi_video# backlight device, make 2 calls: acpi_video_dmi_promote_vendor(); acpi_video_unregister(); The intention here is to make things independent of when acpi_video_register() gets called. As acpi_video_register() will get called on acpi-video load time on non intel gfx machines, while it gets called on i915 load time on intel gfx machines. This leads to the following 2 interesting scenarios: a) intel gfx: 1) acpi-video module gets loaded (as it is a dependency of acpi_vendor and i915) 2) acpi-video does NOT call acpi_video_register() 3) acpi_vendor loads (lets assume it loads before i915), calls acpi_video_dmi_promote_vendor(); which sets ACPI_VIDEO_BACKLIGHT_DMI_VENDOR 4) calls acpi_video_unregister -> not registered, nop 5) i915 loads, calls acpi_video_register 6) acpi_video_register registers the acpi_notifier for the hotkeys, does NOT register a backlight device because of ACPI_VIDEO_BACKLIGHT_DMI_VENDOR b) non intel gfx 1) acpi-video module gets loaded (as it is a dependency acpi_vendor) 2) acpi-video calls acpi_video_register() 3) acpi_video_register registers the acpi_notifier for the hotkeys, and a backlight device 4) acpi_vendor loads, calls acpi_video_dmi_promote_vendor() 5) calls acpi_video_unregister, this unregisters BOTH the acpi_notifier for the hotkeys AND the backlight device So here we have possibly the same acpi_vendor module, making the same calls, but with different results, in one cases acpi-video does handle hotkeys, in the other it does not. Note that the a) scenario turns into b) if we assume the i915 module loads before the vendor_acpi module, so we also have different behavior depending on module loading order! So as said I believe that quite a few existing acpi_vendor modules really always want the behavior of a), hence this patch adds a new acpi_video_unregister_backlight() which gives the behavior of a) independent of module loading order. Signed-off-by: Hans de Goede Reviewed-by: Aaron Lu --- drivers/acpi/video.c | 14 ++++++++++++++ include/acpi/video.h | 2 ++ 2 files changed, 16 insertions(+) diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c index f767eba..898b084 100644 --- a/drivers/acpi/video.c +++ b/drivers/acpi/video.c @@ -2182,6 +2182,20 @@ void acpi_video_unregister(void) } EXPORT_SYMBOL(acpi_video_unregister); +void acpi_video_unregister_backlight(void) +{ + struct acpi_video_bus *video; + + if (!register_count) + return; + + mutex_lock(&video_list_lock); + list_for_each_entry(video, &video_bus_head, entry) + acpi_video_bus_unregister_backlight(video); + mutex_unlock(&video_list_lock); +} +EXPORT_SYMBOL(acpi_video_unregister_backlight); + /* * This is kind of nasty. Hardware using Intel chipsets may require * the video opregion code to be run first in order to initialise diff --git a/include/acpi/video.h b/include/acpi/video.h index 61109f2..4722c06 100644 --- a/include/acpi/video.h +++ b/include/acpi/video.h @@ -19,11 +19,13 @@ struct acpi_device; #if (defined CONFIG_ACPI_VIDEO || defined CONFIG_ACPI_VIDEO_MODULE) extern int acpi_video_register(void); extern void acpi_video_unregister(void); +extern void acpi_video_unregister_backlight(void); extern int acpi_video_get_edid(struct acpi_device *device, int type, int device_id, void **edid); #else static inline int acpi_video_register(void) { return 0; } static inline void acpi_video_unregister(void) { return; } +extern inline void acpi_video_unregister_backlight(void); { return; } static inline int acpi_video_get_edid(struct acpi_device *device, int type, int device_id, void **edid) {