linux-toradex.git/drivers/thermal/thermal_core.c, branch v4.1.21

Thermal: do thermal zone update after a cooling device registered

2016-02-01T19:46:05+00:00

[ Upstream commit 4511f7166a2deb5f7a578cf87fd2fe1ae83527e3 ]

When a new cooling device is registered, we need to update the
thermal zone to set the new registered cooling device to a proper
state.

This fixes a problem that the system is cool, while the fan devices
are left running on full speed after boot, if fan device is registered
after thermal zone device.

Here is the history of why current patch looks like this:
https://patchwork.kernel.org/patch/7273041/

CC:  #3.18+
Reference:https://bugzilla.kernel.org/show_bug.cgi?id=92431
Tested-by: Manuel Krause 
Tested-by: szegad 
Tested-by: prash 
Tested-by: amish 
Reviewed-by: Javi Merino 
Signed-off-by: Zhang Rui 
Signed-off-by: Chen Yu 
Signed-off-by: Sasha Levin

Thermal: handle thermal zone device properly during system sleep

2016-02-01T19:46:01+00:00

[ Upstream commit ff140fea847e1c2002a220571ab106c2456ed252 ]

Current thermal code does not handle system sleep well because
1. the cooling device cooling state may be changed during suspend
2. the previous temperature reading becomes invalid after resumed because
   it is got before system sleep
3. updating thermal zone device during suspending/resuming
   is wrong because some devices may have already been suspended
   or may have not been resumed.

Thus, the proper way to do this is to cancel all thermal zone
device update requirements during suspend/resume, and after all
the devices have been resumed, reset and update every registered
thermal zone devices.

This also fixes a regression introduced by:
Commit 19593a1fb1f6 ("ACPI / fan: convert to platform driver")
Because, with above commit applied, all the fan devices are attached
to the acpi_general_pm_domain, and they are turned on by the pm_domain
automatically after resume, without the awareness of thermal core.

CC:  #3.18+
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=78201
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=91411
Tested-by: Manuel Krause 
Tested-by: szegad 
Tested-by: prash 
Tested-by: amish 
Tested-by: Matthias 
Reviewed-by: Javi Merino 
Signed-off-by: Zhang Rui 
Signed-off-by: Chen Yu 
Signed-off-by: Sasha Levin

Thermal: initialize thermal zone device correctly

2016-02-01T19:45:56+00:00

[ Upstream commit bb431ba26c5cd0a17c941ca6c3a195a3a6d5d461 ]

After thermal zone device registered, as we have not read any
temperature before, thus tz->temperature should not be 0,
which actually means 0C, and thermal trend is not available.
In this case, we need specially handling for the first
thermal_zone_device_update().

Both thermal core framework and step_wise governor is
enhanced to handle this. And since the step_wise governor
is the only one that uses trends, so it's the only thermal
governor that needs to be updated.

CC:  #3.18+
Tested-by: Manuel Krause 
Tested-by: szegad 
Tested-by: prash 
Tested-by: amish 
Tested-by: Matthias 
Reviewed-by: Javi Merino 
Signed-off-by: Zhang Rui 
Signed-off-by: Chen Yu 
Signed-off-by: Sasha Levin

thermal: Do not log an error if thermal_zone_get_temp returns -EAGAIN

2015-04-07T20:11:29+00:00

Some temperature sensors only get updated every few seconds and while
waiting for the first irq reporting a (new) temperature to happen there
get_temp operand will return -EAGAIN as it does not have any data to report
yet.

Not logging an error in this case avoids messages like these from showing
up in dmesg on affected systems:

[    1.219353] thermal thermal_zone0: failed to read out thermal zone 0
[    2.015433] thermal thermal_zone0: failed to read out thermal zone 0
[    2.416737] thermal thermal_zone0: failed to read out thermal zone 0

Reviewed-by: Dmitry Torokhov 
Signed-off-by: Hans de Goede 
Signed-off-by: Eduardo Valentin

thermal: Make sysfs attributes of cooling devices default attributes

2015-03-05T05:47:57+00:00

Default attributes are created when the device is registered. Attributes
created after device registration can lead to race conditions, where user space
(e.g. udev) sees the device but not the attributes.

Signed-off-by: Matthias Kaehlcke 
Signed-off-by: Eduardo Valentin

netlink: make nlmsg_end() and genlmsg_end() void

2015-01-18T06:03:45+00:00

Contrary to common expectations for an "int" return, these functions
return only a positive value -- if used correctly they cannot even
return 0 because the message header will necessarily be in the skb.

This makes the very common pattern of

  if (genlmsg_end(...) < 0) { ... }

be a whole bunch of dead code. Many places also simply do

  return nlmsg_end(...);

and the caller is expected to deal with it.

This also commonly (at least for me) causes errors, because it is very
common to write

  if (my_function(...))
    /* error condition */

and if my_function() does "return nlmsg_end()" this is of course wrong.

Additionally, there's not a single place in the kernel that actually
needs the message length returned, and if anyone needs it later then
it'll be very easy to just use skb->len there.

Remove this, and make the functions void. This removes a bunch of dead
code as described above. The patch adds lines because I did

-	return nlmsg_end(...);
+	nlmsg_end(...);
+	return 0;

I could have preserved all the function's return values by returning
skb->len, but instead I've audited all the places calling the affected
functions and found that none cared. A few places actually compared
the return value with <= 0 in dump functionality, but that could just
be changed to < 0 with no change in behaviour, so I opted for the more
efficient version.

One instance of the error I've made numerous times now is also present
in net/phonet/pn_netlink.c in the route_dumpit() function - it didn't
check for <0 or <=0 and thus broke out of the loop every single time.
I've preserved this since it will (I think) have caused the messages to
userspace to be formatted differently with just a single message for
every SKB returned to userspace. It's possible that this isn't needed
for the tools that actually use this, but I don't even know what they
are so couldn't test that changing this behaviour would be acceptable.

Signed-off-by: Johannes Berg 
Signed-off-by: David S. Miller

Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal into thermal-soc

2014-12-21T14:49:12+00:00

thermal:core:fix: Check return code of the ->get_max_state() callback

2014-12-09T01:32:56+00:00

The return code from ->get_max_state() callback was not checked during
binding cooling device to thermal zone device.

Signed-off-by: Lukasz Majewski 
Signed-off-by: Eduardo Valentin

thermal: Fix error path in thermal_init()

2014-12-08T04:17:25+00:00

thermal_unregister_governors() and class_unregister() were being called in
the wrong order.

Fixes: 80a26a5c22b9 ("Thermal: build thermal governors into thermal_sys module")
Cc: stable@vger.kernel.org
Signed-off-by: Luis Henriques 
Signed-off-by: Zhang Rui

thermal: lock the thermal zone when switching governors

2014-12-08T04:10:44+00:00

Currently, userspace can request a governor change while the governor
itself is running.  Grab the thermal zone lock when changing the
governor to prevent this race.

Signed-off-by: Javi Merino 
Signed-off-by: Zhang Rui