linux-stable.git/drivers/acpi, branch v3.2.58 Linux kernel stable tree ACPI / processor: Rework processor throttling with work_on_cpu() 2014-04-01T23:58:55+00:00 Lan Tianyu tianyu.lan@intel.com 2014-02-26T13:03:05+00:00 bc07f983deb9895504eb35c0970e0abecd57960a commit f3ca4164529b875374c410193bbbac0ee960895f upstream. acpi_processor_set_throttling() uses set_cpus_allowed_ptr() to make sure that the (struct acpi_processor)->acpi_processor_set_throttling() callback will run on the right CPU. However, the function may be called from a worker thread already bound to a different CPU in which case that won't work. Make acpi_processor_set_throttling() use work_on_cpu() as appropriate instead of abusing set_cpus_allowed_ptr(). Reported-and-tested-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> [rjw: Changelog] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit f3ca4164529b875374c410193bbbac0ee960895f upstream.

acpi_processor_set_throttling() uses set_cpus_allowed_ptr() to make
sure that the (struct acpi_processor)->acpi_processor_set_throttling()
callback will run on the right CPU.  However, the function may be
called from a worker thread already bound to a different CPU in which
case that won't work.

Make acpi_processor_set_throttling() use work_on_cpu() as appropriate
instead of abusing set_cpus_allowed_ptr().

Reported-and-tested-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ACPI / video: Filter the _BCL table for duplicate brightness values 2014-04-01T23:58:54+00:00 Hans de Goede hdegoede@redhat.com 2014-02-13T15:32:51+00:00 768b167b17003911a613fde3acbcbc273462e405 commit bd8ba20597f0cfef3ef65c3fd2aa92ab23d4c8e1 upstream. Some devices have duplicate entries in there brightness levels table, ie on my Dell Latitude E6430 the table looks like this: [ 3.686060] acpi backlight index 0, val 80 [ 3.686095] acpi backlight index 1, val 50 [ 3.686122] acpi backlight index 2, val 5 [ 3.686147] acpi backlight index 3, val 5 [ 3.686172] acpi backlight index 4, val 5 [ 3.686197] acpi backlight index 5, val 5 [ 3.686223] acpi backlight index 6, val 5 [ 3.686248] acpi backlight index 7, val 5 [ 3.686273] acpi backlight index 8, val 6 [ 3.686332] acpi backlight index 9, val 7 [ 3.686356] acpi backlight index 10, val 8 [ 3.686380] acpi backlight index 11, val 9 etc. Notice that brightness values 0-5 are all mapped to 5. This means that if userspace writes any value between 0 and 5 to the brightness sysfs attribute and then reads it, it will always return 0, which is somewhat unexpected. This is a problem for ie gnome-settings-daemon, which uses read-modify-write logic when the users presses the brightness up or down keys. This is done this way to take brightness changes from other sources into account. On this specific laptop what happens once the brightness has been set to 0, is that gsd reads 0, adds 5, writes 5, and on the next brightness up key press again reads 0, so things get stuck at the lowest brightness setting. Filtering out the duplicate table entries, makes any write to brightness read back as the written value as one would expect, fixing this. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Aaron Lu <aaron.lu@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit bd8ba20597f0cfef3ef65c3fd2aa92ab23d4c8e1 upstream.

Some devices have duplicate entries in there brightness levels table, ie
on my Dell Latitude E6430 the table looks like this:

[    3.686060] acpi backlight index   0, val 80
[    3.686095] acpi backlight index   1, val 50
[    3.686122] acpi backlight index   2, val 5
[    3.686147] acpi backlight index   3, val 5
[    3.686172] acpi backlight index   4, val 5
[    3.686197] acpi backlight index   5, val 5
[    3.686223] acpi backlight index   6, val 5
[    3.686248] acpi backlight index   7, val 5
[    3.686273] acpi backlight index   8, val 6
[    3.686332] acpi backlight index   9, val 7
[    3.686356] acpi backlight index  10, val 8
[    3.686380] acpi backlight index  11, val 9
etc.

Notice that brightness values 0-5 are all mapped to 5. This means that
if userspace writes any value between 0 and 5 to the brightness sysfs attribute
and then reads it, it will always return 0, which is somewhat unexpected.

This is a problem for ie gnome-settings-daemon, which uses read-modify-write
logic when the users presses the brightness up or down keys. This is done
this way to take brightness changes from other sources into account.

On this specific laptop what happens once the brightness has been set to 0,
is that gsd reads 0, adds 5, writes 5, and on the next brightness up key press
again reads 0, so things get stuck at the lowest brightness setting.

Filtering out the duplicate table entries, makes any write to brightness
read back as the written value as one would expect, fixing this.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ACPI / init: Flag use of ACPI and ACPI idioms for power supplies to regulator API 2014-04-01T23:58:45+00:00 Mark Brown broonie@linaro.org 2014-01-27T00:32:14+00:00 a0746611cff692af285e286f337dcc3bfac02253 commit 49a12877d2777cadcb838981c3c4f5a424aef310 upstream. There is currently no facility in ACPI to express the hookup of voltage regulators, the expectation is that the regulators that exist in the system will be handled transparently by firmware if they need software control at all. This means that if for some reason the regulator API is enabled on such a system it should assume that any supplies that devices need are provided by the system at all relevant times without any software intervention. Tell the regulator core to make this assumption by calling regulator_has_full_constraints(). Do this as soon as we know we are using ACPI so that the information is available to the regulator core as early as possible. This will cause the regulator core to pretend that there is an always on regulator supplying any supply that is requested but that has not otherwise been mapped which is the behaviour expected on a system with ACPI. Should the ability to specify regulators be added in future revisions of ACPI then once we have support for ACPI mappings in the kernel the same assumptions will apply. It is also likely that systems will default to a mode of operation which does not require any interpretation of these mappings in order to be compatible with existing operating system releases so it should remain safe to make these assumptions even if the mappings exist but are not supported by the kernel. Signed-off-by: Mark Brown <broonie@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 49a12877d2777cadcb838981c3c4f5a424aef310 upstream.

There is currently no facility in ACPI to express the hookup of voltage
regulators, the expectation is that the regulators that exist in the
system will be handled transparently by firmware if they need software
control at all. This means that if for some reason the regulator API is
enabled on such a system it should assume that any supplies that devices
need are provided by the system at all relevant times without any software
intervention.

Tell the regulator core to make this assumption by calling
regulator_has_full_constraints(). Do this as soon as we know we are using
ACPI so that the information is available to the regulator core as early
as possible. This will cause the regulator core to pretend that there is
an always on regulator supplying any supply that is requested but that has
not otherwise been mapped which is the behaviour expected on a system with
ACPI.

Should the ability to specify regulators be added in future revisions of
ACPI then once we have support for ACPI mappings in the kernel the same
assumptions will apply. It is also likely that systems will default to a
mode of operation which does not require any interpretation of these
mappings in order to be compatible with existing operating system releases
so it should remain safe to make these assumptions even if the mappings
exist but are not supported by the kernel.

Signed-off-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ACPI / IPMI: Fix atomic context requirement of ipmi_msg_handler() 2013-10-26T20:06:13+00:00 Lv Zheng lv.zheng@intel.com 2013-09-13T05:13:23+00:00 dffcc9dc54d22e3c5eadd5d42835fa47ee25b071 commit 06a8566bcf5cf7db9843a82cde7a33c7bf3947d9 upstream. This patch fixes the issues indicated by the test results that ipmi_msg_handler() is invoked in atomic context. BUG: scheduling while atomic: kipmi0/18933/0x10000100 Modules linked in: ipmi_si acpi_ipmi ... CPU: 3 PID: 18933 Comm: kipmi0 Tainted: G AW 3.10.0-rc7+ #2 Hardware name: QCI QSSC-S4R/QSSC-S4R, BIOS QSSC-S4R.QCI.01.00.0027.070120100606 07/01/2010 ffff8838245eea00 ffff88103fc63c98 ffffffff814c4a1e ffff88103fc63ca8 ffffffff814bfbab ffff88103fc63d28 ffffffff814c73e0 ffff88103933cbd4 0000000000000096 ffff88103fc63ce8 ffff88102f618000 ffff881035c01fd8 Call Trace: <IRQ> [<ffffffff814c4a1e>] dump_stack+0x19/0x1b [<ffffffff814bfbab>] __schedule_bug+0x46/0x54 [<ffffffff814c73e0>] __schedule+0x83/0x59c [<ffffffff81058853>] __cond_resched+0x22/0x2d [<ffffffff814c794b>] _cond_resched+0x14/0x1d [<ffffffff814c6d82>] mutex_lock+0x11/0x32 [<ffffffff8101e1e9>] ? __default_send_IPI_dest_field.constprop.0+0x53/0x58 [<ffffffffa09e3f9c>] ipmi_msg_handler+0x23/0x166 [ipmi_si] [<ffffffff812bf6e4>] deliver_response+0x55/0x5a [<ffffffff812c0fd4>] handle_new_recv_msgs+0xb67/0xc65 [<ffffffff81007ad1>] ? read_tsc+0x9/0x19 [<ffffffff814c8620>] ? _raw_spin_lock_irq+0xa/0xc [<ffffffffa09e1128>] ipmi_thread+0x5c/0x146 [ipmi_si] ... Also Tony Camuso says: We were getting occasional "Scheduling while atomic" call traces during boot on some systems. Problem was first seen on a Cisco C210 but we were able to reproduce it on a Cisco c220m3. Setting CONFIG_LOCKDEP and LOCKDEP_SUPPORT to 'y' exposed a lockdep around tx_msg_lock in acpi_ipmi.c struct acpi_ipmi_device. ================================= [ INFO: inconsistent lock state ] 2.6.32-415.el6.x86_64-debug-splck #1 --------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. ksoftirqd/3/17 [HC0[0]:SC1[1]:HE1:SE0] takes: (&ipmi_device->tx_msg_lock){+.?...}, at: [<ffffffff81337a27>] ipmi_msg_handler+0x71/0x126 {SOFTIRQ-ON-W} state was registered at: [<ffffffff810ba11c>] __lock_acquire+0x63c/0x1570 [<ffffffff810bb0f4>] lock_acquire+0xa4/0x120 [<ffffffff815581cc>] __mutex_lock_common+0x4c/0x400 [<ffffffff815586ea>] mutex_lock_nested+0x4a/0x60 [<ffffffff8133789d>] acpi_ipmi_space_handler+0x11b/0x234 [<ffffffff81321c62>] acpi_ev_address_space_dispatch+0x170/0x1be The fix implemented by this change has been tested by Tony: Tested the patch in a boot loop with lockdep debug enabled and never saw the problem in over 400 reboots. Reported-and-tested-by: Tony Camuso <tcamuso@redhat.com> Signed-off-by: Lv Zheng <lv.zheng@intel.com> Reviewed-by: Huang Ying <ying.huang@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 06a8566bcf5cf7db9843a82cde7a33c7bf3947d9 upstream.

This patch fixes the issues indicated by the test results that
ipmi_msg_handler() is invoked in atomic context.

BUG: scheduling while atomic: kipmi0/18933/0x10000100
Modules linked in: ipmi_si acpi_ipmi ...
CPU: 3 PID: 18933 Comm: kipmi0 Tainted: G       AW    3.10.0-rc7+ #2
Hardware name: QCI QSSC-S4R/QSSC-S4R, BIOS QSSC-S4R.QCI.01.00.0027.070120100606 07/01/2010
 ffff8838245eea00 ffff88103fc63c98 ffffffff814c4a1e ffff88103fc63ca8
 ffffffff814bfbab ffff88103fc63d28 ffffffff814c73e0 ffff88103933cbd4
 0000000000000096 ffff88103fc63ce8 ffff88102f618000 ffff881035c01fd8
Call Trace:
 <IRQ>  [<ffffffff814c4a1e>] dump_stack+0x19/0x1b
 [<ffffffff814bfbab>] __schedule_bug+0x46/0x54
 [<ffffffff814c73e0>] __schedule+0x83/0x59c
 [<ffffffff81058853>] __cond_resched+0x22/0x2d
 [<ffffffff814c794b>] _cond_resched+0x14/0x1d
 [<ffffffff814c6d82>] mutex_lock+0x11/0x32
 [<ffffffff8101e1e9>] ? __default_send_IPI_dest_field.constprop.0+0x53/0x58
 [<ffffffffa09e3f9c>] ipmi_msg_handler+0x23/0x166 [ipmi_si]
 [<ffffffff812bf6e4>] deliver_response+0x55/0x5a
 [<ffffffff812c0fd4>] handle_new_recv_msgs+0xb67/0xc65
 [<ffffffff81007ad1>] ? read_tsc+0x9/0x19
 [<ffffffff814c8620>] ? _raw_spin_lock_irq+0xa/0xc
 [<ffffffffa09e1128>] ipmi_thread+0x5c/0x146 [ipmi_si]
 ...

Also Tony Camuso says:

 We were getting occasional "Scheduling while atomic" call traces
 during boot on some systems. Problem was first seen on a Cisco C210
 but we were able to reproduce it on a Cisco c220m3. Setting
 CONFIG_LOCKDEP and LOCKDEP_SUPPORT to 'y' exposed a lockdep around
 tx_msg_lock in acpi_ipmi.c struct acpi_ipmi_device.

 =================================
 [ INFO: inconsistent lock state ]
 2.6.32-415.el6.x86_64-debug-splck #1
 ---------------------------------
 inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
 ksoftirqd/3/17 [HC0[0]:SC1[1]:HE1:SE0] takes:
  (&ipmi_device->tx_msg_lock){+.?...}, at: [<ffffffff81337a27>] ipmi_msg_handler+0x71/0x126
 {SOFTIRQ-ON-W} state was registered at:
   [<ffffffff810ba11c>] __lock_acquire+0x63c/0x1570
   [<ffffffff810bb0f4>] lock_acquire+0xa4/0x120
   [<ffffffff815581cc>] __mutex_lock_common+0x4c/0x400
   [<ffffffff815586ea>] mutex_lock_nested+0x4a/0x60
   [<ffffffff8133789d>] acpi_ipmi_space_handler+0x11b/0x234
   [<ffffffff81321c62>] acpi_ev_address_space_dispatch+0x170/0x1be

The fix implemented by this change has been tested by Tony:

 Tested the patch in a boot loop with lockdep debug enabled and never
 saw the problem in over 400 reboots.

Reported-and-tested-by: Tony Camuso <tcamuso@redhat.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Reviewed-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ACPI / EC: Add ASUSTEK L4R to quirk list in order to validate ECDT 2013-10-26T20:06:00+00:00 Lan Tianyu tianyu.lan@intel.com 2013-08-26T02:19:18+00:00 934796aadc4cf907d21b9346b70383d520bd0eea commit 524f42fab787a9510be826ce3d736b56d454ac6d upstream. The ECDT of ASUSTEK L4R doesn't provide correct command and data I/O ports. The DSDT provides the correct information instead. For this reason, add this machine to quirk list for ECDT validation and use the EC information from the DSDT. [rjw: Changelog] References: https://bugzilla.kernel.org/show_bug.cgi?id=60765 Reported-and-tested-by: Daniele Esposti <expo@expobrain.net> Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 524f42fab787a9510be826ce3d736b56d454ac6d upstream.

The ECDT of ASUSTEK L4R doesn't provide correct command and data
I/O ports.  The DSDT provides the correct information instead.

For this reason, add this machine to quirk list for ECDT validation
and use the EC information from the DSDT.

[rjw: Changelog]
References: https://bugzilla.kernel.org/show_bug.cgi?id=60765
Reported-and-tested-by: Daniele Esposti <expo@expobrain.net>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ACPI / battery: Fix parsing _BIX return value 2013-09-10T00:57:18+00:00 Lan Tianyu tianyu.lan@intel.com 2013-07-30T12:00:42+00:00 45cc55f9365e8a43a5a0394a654abc8f966946e9 commit 016d5baad04269e8559332df05f89bd95b52d6ad upstream. The _BIX method returns extended battery info as a package. According the ACPI spec (ACPI 5, Section 10.2.2.2), the first member of that package should be "Revision". However, the current ACPI battery driver treats the first member as "Power Unit" which should be the second member. This causes the result of _BIX return data parsing to be incorrect. Fix this by adding a new member called 'revision' to struct acpi_battery and adding the offsetof() information on it to extended_info_offsets[] as the first row. [rjw: Changelog] Reported-and-tested-by: Jan Hoffmann <jan.christian.hoffmann@gmail.com> References: http://bugzilla.kernel.org/show_bug.cgi?id=60519 Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 016d5baad04269e8559332df05f89bd95b52d6ad upstream.

The _BIX method returns extended battery info as a package.
According the ACPI spec (ACPI 5, Section 10.2.2.2), the first member
of that package should be "Revision".  However, the current ACPI
battery driver treats the first member as "Power Unit" which should
be the second member.  This causes the result of _BIX return data
parsing to be incorrect.

Fix this by adding a new member called 'revision' to struct
acpi_battery and adding the offsetof() information on it to
extended_info_offsets[] as the first row.

[rjw: Changelog]
Reported-and-tested-by: Jan Hoffmann <jan.christian.hoffmann@gmail.com>
References: http://bugzilla.kernel.org/show_bug.cgi?id=60519
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ACPI / memhotplug: Fix a stale pointer in error path 2013-08-02T20:14:55+00:00 Toshi Kani toshi.kani@hp.com 2013-07-10T16:47:13+00:00 3e75362130f7535081b1e72911404d5f9030df82 commit d19f503e22316a84c39bc19445e0e4fdd49b3532 upstream. device->driver_data needs to be cleared when releasing its data, mem_device, in an error path of acpi_memory_device_add(). The function evaluates the _CRS of memory device objects, and fails when it gets an unexpected resource or cannot allocate memory. A kernel crash or data corruption may occur when the kernel accesses the stale pointer. Signed-off-by: Toshi Kani <toshi.kani@hp.com> Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit d19f503e22316a84c39bc19445e0e4fdd49b3532 upstream.

device->driver_data needs to be cleared when releasing its data,
mem_device, in an error path of acpi_memory_device_add().

The function evaluates the _CRS of memory device objects, and fails
when it gets an unexpected resource or cannot allocate memory.  A
kernel crash or data corruption may occur when the kernel accesses
the stale pointer.

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ACPI / video: ignore BIOS initial backlight value for HP Pavilion g6 2013-06-19T01:16:52+00:00 Ash Willis ashwillis.kernel@gmail.com 2013-05-29T01:27:59+00:00 8de5f8abdee26b1dc13e98c401a68637df2ad0dc commit 780a6ec640a3fed671fc2c40e4dd30c03eca3ac3 upstream. This patch addresses kernel bug 56661. BIOS reports an incorrect backlight value, causing the driver to switch off the backlight completely during startup. This patch ignores the incorrect value from BIOS. References: https://bugzilla.kernel.org/show_bug.cgi?id=56661 Signed-off-by: Ash Willis <ashwillis@programmer.net> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 780a6ec640a3fed671fc2c40e4dd30c03eca3ac3 upstream.

This patch addresses kernel bug 56661. BIOS reports an incorrect
backlight value, causing the driver to switch off the backlight
completely during startup. This patch ignores the incorrect value from
BIOS.

References: https://bugzilla.kernel.org/show_bug.cgi?id=56661
Signed-off-by: Ash Willis <ashwillis@programmer.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ACPI / video: ignore BIOS initial backlight value for HP m4 2013-06-19T01:16:52+00:00 Alex Hung alex.hung@canonical.com 2013-05-28T02:05:09+00:00 10254e3d0182b24685f1043183194c7a6d26a2e9 commit fedbe9bc6fd3e14b1ffbb3dac407777ac4a3650c upstream. On HP m4 lapops, BIOS reports minimum backlight on boot and causes backlight to dim completely. This ignores the initial backlight values and set to max brightness. References: https://bugs.launchpad.net/bugs/1184501 Signed-off-by: Alex Hung <alex.hung@canonical.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit fedbe9bc6fd3e14b1ffbb3dac407777ac4a3650c upstream.

On HP m4 lapops, BIOS reports minimum backlight on boot and
causes backlight to dim completely. This ignores the initial backlight
values and set to max brightness.

References: https://bugs.launchpad.net/bugs/1184501
Signed-off-by: Alex Hung <alex.hung@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ACPI video: ignore BIOS initial backlight value for HP 1000 2013-06-19T01:16:52+00:00 Alex Hung alex.hung@canonical.com 2013-05-06T08:23:43+00:00 36466ac6c36c955ec1e4eaf8f4ed6a192f430f9a commit 4ef366c583d6180b1c951147869ee5a3038834f2 upstream. On HP 1000 lapops, BIOS reports minimum backlight on boot and causes backlight to dim completely. This ignores the initial backlight values and set to max brightness. References:: https://bugs.launchpad.net/bugs/1167760 Signed-off-by: Alex Hung <alex.hung@canonical.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 4ef366c583d6180b1c951147869ee5a3038834f2 upstream.

On HP 1000 lapops, BIOS reports minimum backlight on boot and
causes backlight to dim completely. This ignores the initial backlight
values and set to max brightness.

References:: https://bugs.launchpad.net/bugs/1167760
Signed-off-by: Alex Hung <alex.hung@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>