linux-kernel - Re: [PATCH 2/3] ACPI / video: Always call acpi_video_init

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <1374126011.6123.2.camel@ThinkPad-X230.localdomain>
Date:	Thu, 18 Jul 2013 09:40:11 +0400
From:	Igor Gnatenko <i.gnatenko.brain@...il.com>
To:	"Rafael J. Wysocki" <rjw@...k.pl>
Cc:	linux-acpi@...r.kernel.org,
	Matthew Garrett <matthew.garrett@...ula.com>,
	seth.forshee@...onical.com, joeyli.kernel@...il.com,
	daniel.vetter@...ll.ch, intel-gfx@...ts.freedesktop.org,
	dri-devel@...ts.freedesktop.org, linux-kernel@...r.kernel.org,
	lenb@...nel.org, Aaron Lu <aaron.lu@...el.com>,
	Yves-Alexis Perez <corsac@...ian.org>,
	Felipe Contreras <felipe.contreras@...il.com>,
	"Lee, Chun-Yi" <jlee@...e.com>,
	Henrique de Moraes Holschuh <hmh@....eng.br>
Subject: Re: [PATCH 2/3] ACPI / video: Always call
 acpi_video_init_brightness() on init

From: Matthew Garrett <matthew.garrett@...ula.com>

We have to call acpi_video_init_brightness() even if we're not going
to initialise the backlight - Thinkpads seem to use this as the
trigger for enabling ACPI notifications rather than handling it in
firmware.

[rjw: Drop the brightness object created by
 acpi_video_init_brightness() if we are not going to use it.]
Signed-off-by: Matthew Garrett <matthew.garrett@...ula.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@...el.com>
Tested-by: Igor Gnatenko <i.gnatenko.brain@...il.com>
---
 drivers/acpi/video.c |   11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

Index: linux-pm/drivers/acpi/video.c
===================================================================
--- linux-pm.orig/drivers/acpi/video.c
+++ linux-pm/drivers/acpi/video.c
@@ -884,6 +884,9 @@ static void acpi_video_device_find_cap(s
 	if (acpi_has_method(device->dev->handle, "_DDC"))
 		device->cap._DDC = 1;
 
+	if (acpi_video_init_brightness(device))
+		return;
+
 	if (acpi_video_backlight_support()) {
 		struct backlight_properties props;
 		struct pci_dev *pdev;
@@ -893,9 +896,6 @@ static void acpi_video_device_find_cap(s
 		static int count = 0;
 		char *name;
 
-		result = acpi_video_init_brightness(device);
-		if (result)
-			return;
 		name = kasprintf(GFP_KERNEL, "acpi_video%d", count);
 		if (!name)
 			return;
@@ -955,6 +955,11 @@ static void acpi_video_device_find_cap(s
 		if (result)
 			printk(KERN_ERR PREFIX "Create sysfs link\n");
 
+	} else {
+		/* Remove the brightness object. */
+		kfree(device->brightness->levels);
+		kfree(device->brightness);
+		device->brightness = NULL;
 	}
 }
 

-- 
Igor Gnatenko
Fedora release 19 (Schrödinger’s Cat)
Linux 3.9.9-302.fc19.x86_64

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/