linux-toradex.git/drivers/devfreq/devfreq.c, branch v4.17

PM / devfreq: Fix potential NULL pointer dereference in governor_store

2018-01-02T00:36:54+00:00

df->governor is being dereferenced before it is null checked,
hence there is a potential null pointer dereference.

Notice that df->governor is being null checked at line 1004:
if (df->governor) {, which implies it might be null.

Fix this by null checking df->governor before dereferencing it.

Addresses-Coverity-ID: 1401988 ("Dereference before null check")
Fixes: bcf23c79c4e4 ("PM / devfreq: Fix available_governor sysfs")
Signed-off-by: Gustavo A. R. Silva 
Reviewed-by: Chanwoo Choi 
Signed-off-by: MyungJoo Ham

PM / devfreq: Propagate error from devfreq_add_device()

2018-01-02T00:36:54+00:00

Propagate the error of devfreq_add_device() in devm_devfreq_add_device()
rather than statically returning ENOMEM. This makes it slightly faster
to pinpoint the cause of a returned error.

Fixes: 8cd84092d35e ("PM / devfreq: Add resource-managed function for devfreq device")
Cc: stable@vger.kernel.org
Acked-by: Chanwoo Choi 
Signed-off-by: Bjorn Andersson 
Signed-off-by: MyungJoo Ham

PM / devfreq: Remove unneeded conditional statement

2017-10-26T08:08:40+00:00

The freq_table array of each devfreq device is always not NULL.
In result, it is unneeded to check whether profile->freq_table
is NULL or not.

Signed-off-by: Chanwoo Choi 
Signed-off-by: MyungJoo Ham

PM / devfreq: Show the all available frequencies

2017-10-26T08:08:40+00:00

The commit a76caf55e5b35 ("thermal: Add devfreq cooling") allows
the devfreq device to use the cooling device. When the cooling down
are required, the devfreq_cooling.c disables the OPP entry with
the dev_pm_opp_disable(). In result, 'available_frequencies'[1]
sysfs node never came to show the all available frequencies.
[1] /sys/class/devfreq/.../available_frequencies

So, this patch uses the 'freq_table' in the 'struct devfreq_dev_profile'
in order to show the all available frequencies.
- If 'freq_table' is NULL, devfreq core initializes them by using OPP values.
- If 'freq_table' is initialized, devfreq core just uses the 'freq_table'.

And this patch adds some comment about the sort way of 'freq_table'.

Signed-off-by: Chanwoo Choi 
Signed-off-by: MyungJoo Ham

PM / devfreq: Change return type of devfreq_set_freq_table()

2017-10-26T08:08:40+00:00

This patch changes the return type of devfreq_set_freq_table()
from 'void' to 'int' in order to check whether it fails or not.

And This patch just removes the 'devfreq' prefix and the description
of function. Because the helper functions are only used by the devfreq.

Signed-off-by: Chanwoo Choi 
Signed-off-by: MyungJoo Ham

PM / devfreq: Use the available min/max frequency

2017-10-26T08:08:40+00:00

The commit a76caf55e5b35 ("thermal: Add devfreq cooling") is able
to disable OPP as a cooling device. In result, both update_devfreq()
and {min|max}_freq_show() have to consider the 'opp->available'
status of each OPP.

So, this patch adds the 'scaling_{min|max}_freq' to struct devfreq
in order to indicate the available mininum and maximum frequency
by adjusting OPP interface such as dev_pm_opp_{disable|enable}().
The 'scaling_{min|max}_freq' are used for on both update_devfreq()
and {min|max}_freq_show().

Signed-off-by: Chanwoo Choi 
Signed-off-by: MyungJoo Ham

Revert "PM / devfreq: Add show_one macro to delete the duplicate code"

2017-10-26T08:08:40+00:00

This reverts commit 3104fa3081126c9bda35793af5f335d0ee0d5818.

The {min|max}_freq_show() show the stored value of the struct devfreq.
But, if the drivers/thermal/devfreq_cooling.c disables the specific
frequency value, {min|max}_freq_show() have to check this situation
before showing the stored value. So, this patch revert the macro
in order to add the additional codes.

Signed-off-by: Chanwoo Choi 
Signed-off-by: MyungJoo Ham

PM / devfreq: Set min/max_freq when adding the devfreq device

2017-10-26T08:08:40+00:00

Prior to that, the min/max_freq of the devfreq device are always zero
before the user changes the min/max_freq through sysfs entries.
It might make the confusion for the min/max_freq.

This patch initializes the available min/max_freq by using the OPP
during adding the devfreq device.

Signed-off-by: Chanwoo Choi 
Signed-off-by: MyungJoo Ham

PM / devfreq: Fix memory leak when fail to register device

2017-08-28T01:31:08+00:00

When the devfreq_add_device fails to register deivce, the memory
leak of devfreq instance happen. So, this patch fix the memory
leak issue. Before freeing the devfreq instance checks whether
devfreq instance is NULL or not because the device_unregister()
frees the devfreq instance when jumping to the 'err_init'.
It is to prevent the duplicate the kfee(devfreq).

Cc: stable@vger.kernel.org
Fixes: ac4b281176a5 ("PM / devfreq: fix duplicated kfree on devfreq pointer")
Signed-off-by: Chanwoo Choi 
Signed-off-by: MyungJoo Ham

scripts/spelling.txt: add "followings" pattern and fix typo instances

2017-02-28T02:43:47+00:00

Fix typos and add the following to the scripts/spelling.txt:

  followings||following

While we are here, add a missing colon in the boilerplate in DT binding
documents.  The "you SoC" in allwinner,sunxi-pinctrl.txt was fixed as
well.

I reworded "as the followings:" to "as follows:" for
drivers/usb/gadget/udc/renesas_usb3.c.

Link: http://lkml.kernel.org/r/1481573103-11329-32-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds