kernel news – 26.11.2013

Posted: November 26, 2013 in kernel

-Eduardo Valentin has the following changes for thermal and device
aimed at 3.14 :

Please consider the following changes for 3.14. It contains the work of
representing hardware thermal using device tree. It also contains
three examples on how to use the new representation on sensor devices,
using three different drivers to accomplish it. One driver is on thermal
subsystem, the TI SoC thermal, and the other two drivers are in hwmon
subsystem. I also included a change on cpu cooling device, which required
also a change on cpufreq-cpu0 driver. The change on this cooling device
still keeps in one piece its usage on different platforms.

Because it is a controversial topic due to the lack of standards, and
because it touches different subsystems, it took way longer than I expected.
However, I’ve been discussing in different channels, and I believe I got
enough entropy now to go forward. We have acks from cpufreq folks (on ARM side)
and from hwmon folks too. Raphael W., Jean D. and Mark R. have also
reviewed this series. They agree with the core idea of the work.

It has been agreed that this is not the end of it. As I said I started
with only three examples, but there are other potential drivers to use
this API. So, I have agreed with Jean D., for instance, that this
series would be first step of the complete work. Next would be to check
other potential drivers to be converted and then validate the proposed
API. Currently the thermal framework would be polling for device
temperature, but we could implement a couple of call backs to setup
update rate, thresholds and hysteresis too, for instance.

On the other hand, I don’t think the principle and concept would break
after converting the remaining drivers. That is why I am sending this pull

Another point is, as you can see, there are several points in this pull
request that do not belong to thermal subsystem. It has been suggested
by Guenter R. that in such cases, it is recommended to send the complete
series via one single subsystem. Thus, I am sending via your queue.

Lastly, I’ve also volunteered to maintain the upcoming thermal bindings.
Then, you can see I am adding thermal bindings to our MAINTAINERS entry too.

-Felipe Balbi has USB changes for -rc2 :

First set of fixes for this -rc cycle. A few important
fixes which should be backported to stable kernels and
the usual set of sparse warning fixes. There’s also a
regression fix on phy-generic.c which would prevent
am335x-based platforms from having their PHY drivers

-Regulator fixes from Mark Brown :

A bunch of fixes, a few driver specific ones and a framework fix for
voltage enumeration on fixed voltage regulators which had previously
worked but had been misplaced during some refactoring causing problems
for users that needed to know the voltage.

-Arnaldo Carvalho de Melo has perf/core improvements and fixes :

. Make per-cpu mmaps the default in ‘perf record’, from Adrian Hunter.

. Default -t/–thread ‘perf record’ option to no inheritance,
from Adrian Hunter.

. Make ‘perf top -g’ refer to callchains, for consistency with other tools,
from David Ahern.

. Skip ignored symbols while printing callchain, from David Ahern.

. Print callchains and symbols if they exist in ‘perf script’,
from David Ahern.

. Remove thread summary coloring in ‘perf trace’, from Pekka Enberg.

. zsh completion support, from Ramkumar Ramachandra.

. ‘perf timechart’ improvements, including backtrace support,
from Stanislav Fomichev.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s