Re: [PATCH v1] clk: Add devm_clk_{prepare,enable,prepare_enable}

Marc Gonzalez
2019-11-25T13:16:20Z

On 25/11/2019 13:52, Russell King - ARM Linux admin wrote:

> On Mon, Nov 25, 2019 at 01:46:51PM +0100, Marc Gonzalez wrote:
>
>> On 15/07/2019 17:34, Marc Gonzalez wrote:
>>
>>> Provide devm variants for automatic resource release on device removal.
>>> probe() error-handling is simpler, and remove is no longer required.
>>>
>>> Signed-off-by: Marc Gonzalez <marc.w.gonzalez@free.fr>
>>> ---
>>> Documentation/driver-model/devres.rst | 3 +++
>>> drivers/clk/clk.c | 24 ++++++++++++++++++++++++
>>> include/linux/clk.h | 8 ++++++++
>>> 3 files changed, 35 insertions(+)
>>>
>>> diff --git a/Documentation/driver-model/devres.rst b/Documentation/driver-model/devres.rst
>>> index 1b6ced8e4294..9357260576ef 100644
>>> --- a/Documentation/driver-model/devres.rst
>>> +++ b/Documentation/driver-model/devres.rst
>>> @@ -253,6 +253,9 @@ CLOCK
>>> devm_clk_hw_register()
>>> devm_of_clk_add_hw_provider()
>>> devm_clk_hw_register_clkdev()
>>> + devm_clk_prepare()
>>> + devm_clk_enable()
>>> + devm_clk_prepare_enable()
>>>
>>> DMA
>>> dmaenginem_async_device_register()
>>> diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
>>> index c0990703ce54..5e85548357c0 100644
>>> --- a/drivers/clk/clk.c
>>> +++ b/drivers/clk/clk.c
>>> @@ -914,6 +914,18 @@ int clk_prepare(struct clk *clk)
>>> }
>>> EXPORT_SYMBOL_GPL(clk_prepare);
>>>
>>> +static void unprepare(void *clk)
>>> +{
>>> + clk_unprepare(clk);
>>> +}
>>> +
>>> +int devm_clk_prepare(struct device *dev, struct clk *clk)
>>> +{
>>> + int rc = clk_prepare(clk);
>>> + return rc ? : devm_add_action_or_reset(dev, unprepare, clk);
>>> +}
>>> +EXPORT_SYMBOL_GPL(devm_clk_prepare);
>>> +
>>> static void clk_core_disable(struct clk_core *core)
>>> {
>>> lockdep_assert_held(&enable_lock);
>>> @@ -1136,6 +1148,18 @@ int clk_enable(struct clk *clk)
>>> }
>>> EXPORT_SYMBOL_GPL(clk_enable);
>>>
>>> +static void disable(void *clk)
>>> +{
>>> + clk_disable(clk);
>>> +}
>>> +
>>> +int devm_clk_enable(struct device *dev, struct clk *clk)
>>> +{
>>> + int rc = clk_enable(clk);
>>> + return rc ? : devm_add_action_or_reset(dev, disable, clk);
>>> +}
>>> +EXPORT_SYMBOL_GPL(devm_clk_enable);
>>> +
>>> static int clk_core_prepare_enable(struct clk_core *core)
>>> {
>>> int ret;
>>> diff --git a/include/linux/clk.h b/include/linux/clk.h
>>> index 3c096c7a51dc..d09b5207e3f1 100644
>>> --- a/include/linux/clk.h
>>> +++ b/include/linux/clk.h
>>> @@ -895,6 +895,14 @@ static inline void clk_restore_context(void) {}
>>>
>>> #endif
>>>
>>> +int devm_clk_prepare(struct device *dev, struct clk *clk);
>>> +int devm_clk_enable(struct device *dev, struct clk *clk);
>>> +static inline int devm_clk_prepare_enable(struct device *dev, struct clk *clk)
>>> +{
>>> + int rc = devm_clk_prepare(dev, clk);
>>> + return rc ? : devm_clk_enable(dev, clk);
>>> +}
>>> +
>>> /* clk_prepare_enable helps cases using clk_enable in non-atomic context. */
>>> static inline int clk_prepare_enable(struct clk *clk)
>>> {
>>
>> Thoughts? Comments?
>
> These are part of the clk API rather than the CCF API, and belong in
> drivers/clk/clk-devres.c.

I'm totally confused.

Are you saying that a hypothetical devm_clk_prepare() function should not be
implemented in the same file as the "raw" clk_prepare() ?

Regards.