[PATCH] clk: Manage proper runtime PM state in clk_change_rate()

[Stephen Boyd]

On 11/30, Marek Szyprowski wrote:
> clk_change_rate() propagates rate change down to all its children. Such
> operation requires managing proper runtime PM state of each child, what
> was missing. Add needed calls to clk_pm_runtime*() to ensure that
> set_rate() clock callback is called on runtime active clock.
> 
> This fixes following issue found on Exynos5433 TM2 board with devfreq
> enabled:
> 
> Synchronous External Abort: synchronous external abort (0x96000210) at 0xffffff80093f5600
> Internal error: : 96000210 [#1] PREEMPT SMP
> Modules linked in:
> CPU: 0 PID: 5 Comm: kworker/u16:0 Not tainted 4.15.0-rc1-next-20171129+ #4
> Hardware name: Samsung TM2 board (DT)
> Workqueue: devfreq_wq devfreq_monitor
> task: ffffffc0ca96b600 task.stack: ffffff80093a8000
> pstate: a0000085 (NzCv daIf -PAN -UAO)
> pc : clk_divider_set_rate+0x54/0x118
> lr : clk_divider_set_rate+0x44/0x118
> ...
> Process kworker/u16:0 (pid: 5, stack limit = 0xffffff80093a8000)
> Call trace:
>  clk_divider_set_rate+0x54/0x118
>  clk_change_rate+0xfc/0x4e0
>  clk_change_rate+0x1f0/0x4e0
>  clk_change_rate+0x1f0/0x4e0
>  clk_change_rate+0x1f0/0x4e0
>  clk_core_set_rate_nolock+0x138/0x148
>  clk_set_rate+0x28/0x50
>  exynos_bus_passive_target+0x6c/0x11c
>  update_devfreq_passive+0x58/0xb4
>  devfreq_passive_notifier_call+0x50/0x5c
>  notifier_call_chain+0x4c/0x88
>  __srcu_notifier_call_chain+0x54/0x80
>  srcu_notifier_call_chain+0x14/0x1c
>  update_devfreq+0x100/0x1b4
>  devfreq_monitor+0x2c/0x88
>  process_one_work+0x148/0x3d8
>  worker_thread+0x13c/0x3f8
>  kthread+0x100/0x12c
>  ret_from_fork+0x10/0x18
> 
> Reported-by: Chanwoo Choi <cw00.choi at samsung.com>
> Fixes: 9a34b45397e5 ("clk: Add support for runtime PM")
> Signed-off-by: Marek Szyprowski <m.szyprowski at samsung.com>
> ---

Applied to clk-fixes

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