Previously, non-generic attributes (polling_interval, timer) used separate
create/delete logic, leading to race conditions during concurrent access in
creation/deletion. Multi-threaded operations also caused inconsistencies
between governor capabilities and attribute states.

1.Use is_visible + sysfs_update_group() to unify management of these
attributes, eliminating creation/deletion races.
2.Add locks and validation to these attributes, ensuring consistency
between current governor capabilities and attribute operations in
multi-threaded environments.

Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Jie Zhan <zhanjie9@hisilicon.com>
Signed-off-by: Pengjie Zhang <zhangpengjie2@huawei.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Link: https://www.spinics.net/lists/kernel/msg5967745.html

HZ_PER_KHZ is defined as UL (unsigned long), no need to repeat that.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Lifeng Zheng <zhenglifeng1@huawei.com>
Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Link: https://lore.kernel.org/lkml/20260114093115.276818-1-andriy.shevchenko@linux.intel.com/

This was done entirely with mindless brute force, using

    git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook <kees@kernel.org>

Some device drivers (and out-of-tree modules) might want to define
device-specific device governors. Rather than restricting all of them to
be a part of drivers/devfreq/ (which is not possible for out-of-tree
drivers anyway) move governor.h to include/linux/devfreq-governor.h and
update all drivers to use it.

The devfreq_cpu_data is only used internally, by the passive governor,
so it is moved to the driver source rather than being a part of the
public interface.

Reported-by: Robie Basak <robibasa@qti.qualcomm.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Reviewed-by: Bjorn Andersson <andersson@kernel.org>
Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Link: https://patchwork.kernel.org/project/linux-pm/patch/20251030-governor-public-v2-1-432a11a9975a@oss.qualcomm.com/

Extend the devfreq_dev_profile to allow drivers optionally create
device-specific sysfs ABIs together with other common devfreq ABIs under
the devfreq device path.

Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Huisong Li <lihuisong@huawei.com>
Signed-off-by: Jie Zhan <zhanjie9@hisilicon.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Link: https://patchwork.kernel.org/project/linux-pm/patch/20250623143401.4095045-2-zhanjie9@hisilicon.com/

Fixes: 4920ee6dcfaf ("PM / devfreq: Convert to use sysfs_emit_at() API")
Signed-off-by: pls <pleasurefish@126.com>
Link: https://patchwork.kernel.org/project/linux-pm/patch/20250515143100.17849-1-chanwoo@kernel.org/
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>

Commit 96ffcdf239de ("PM / devfreq: Remove redundant governor_name from
struct devfreq") removes governor_name and uses governor->name to replace
it. But devfreq->governor may be NULL and directly using
devfreq->governor->name may cause null pointer exception. Move the check of
governor to before using governor->name.

Fixes: 96ffcdf239de ("PM / devfreq: Remove redundant governor_name from struct devfreq")
Signed-off-by: Lifeng Zheng <zhenglifeng1@huawei.com>
Link: https://lore.kernel.org/lkml/20250421030020.3108405-5-zhenglifeng1@huawei.com/
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>

The calling of devfreq_get_freq_range() in devfreq_add_device() is
redundant because min_freq and max_freq are never used. Remove it.

Signed-off-by: Lifeng Zheng <zhenglifeng1@huawei.com>
Link: https://lore.kernel.org/lkml/20250421030020.3108405-4-zhenglifeng1@huawei.com/
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>

Limit max_freq in devfreq_get_freq_range() with scaling_min_freq to avoid
showing an unreachable freq when reading it.

Use macro clamp to simplify code.

Signed-off-by: Lifeng Zheng <zhenglifeng1@huawei.com>
Link: https://lore.kernel.org/lkml/20250421030020.3108405-3-zhenglifeng1@huawei.com/
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>