diff options
| author | Rene Bollford <xsecute@googlemail.com> | 2011-10-23 09:56:42 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2012-01-18 07:31:54 -0800 |
| commit | 910fc79f722372dcc17ff3c53e1f2191c0cf816c (patch) | |
| tree | 4c9994d24aca2f6d33a1375817d30c3c37500d40 /drivers/platform/x86 | |
| parent | c4e7f9022e506c6635a5037713c37118e23193e4 (diff) | |
ideapad: Check if acpi already handle backlight power to avoid a page fault
commit d4afc7754a60b885b63ef23fd194984e2d53a4e6 upstream.
This patch avoid a page fault in the ideapad-laptop extras when
turning the backlight power on or off.
Signed-off-by: Rene Bolldorf <xsecute@googlemail.com>
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Tested-by: Artem X <artem.brz@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/platform/x86')
| -rw-r--r-- | drivers/platform/x86/ideapad-laptop.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/platform/x86/ideapad-laptop.c b/drivers/platform/x86/ideapad-laptop.c index 0c595410e788..0d94eec00f4d 100644 --- a/drivers/platform/x86/ideapad-laptop.c +++ b/drivers/platform/x86/ideapad-laptop.c @@ -493,6 +493,8 @@ static void ideapad_backlight_notify_power(struct ideapad_private *priv) unsigned long power; struct backlight_device *blightdev = priv->blightdev; + if (!blightdev) + return; if (read_ec_data(ideapad_handle, 0x18, &power)) return; blightdev->props.power = power ? FB_BLANK_UNBLANK : FB_BLANK_POWERDOWN; |