[v3,1/2] clk: Provide managed helper to get and enable bulk clocks

Commit Message

Shradha Todi Jan. 10, 2024, 11:01 a.m. UTC

Provide a managed devm_clk_bulk* wrapper to get and enable all
bulk clocks in order to simplify drivers that keeps all clocks
enabled for the time of driver operation.

Suggested-by: Marek Szyprowski <[e-mail]>
Signed-off-by: Shradha Todi <[e-mail]>
---
 drivers/clk/clk-devres.c | 41 ++++++++++++++++++++++++++++++++++++++++
 include/linux/clk.h      | 25 ++++++++++++++++++++++++
 2 files changed, 66 insertions(+)

Comments

Alim Akhtar Jan. 10, 2024, 12:31 p.m. UTC | #1

Hi Shradha,

> -----Original Message-----
> From: Shradha Todi <[e-mail]>
> Sent: Wednesday, January 10, 2024 4:31 PM
> To: [e-mail]; [e-mail]; linux-
> [e-mail]; [e-mail]; linux-samsung-
> [e-mail]
> Cc: [e-mail]; [e-mail]; [e-mail];
> [e-mail]; [e-mail]; [e-mail];
> [e-mail]; [e-mail];
> [e-mail]; [e-mail];
> [e-mail]; [e-mail]; Shradha
> Todi <[e-mail]>
> Subject: [PATCH v3 1/2] clk: Provide managed helper to get and enable bulk
> clocks
> 
> Provide a managed devm_clk_bulk* wrapper to get and enable all bulk clocks
> in order to simplify drivers that keeps all clocks enabled for the time of driver
> operation.
> 
> Suggested-by: Marek Szyprowski <[e-mail]>
> Signed-off-by: Shradha Todi <[e-mail]>
> ---
>  drivers/clk/clk-devres.c | 41
> ++++++++++++++++++++++++++++++++++++++++
>  include/linux/clk.h      | 25 ++++++++++++++++++++++++
>  2 files changed, 66 insertions(+)
> 
> diff --git a/drivers/clk/clk-devres.c b/drivers/clk/clk-devres.c index
> 4fb4fd4b06bd..05b0ff4bc1d4 100644
> --- a/drivers/clk/clk-devres.c
> +++ b/drivers/clk/clk-devres.c
> @@ -102,6 +102,7 @@
> EXPORT_SYMBOL_GPL(devm_clk_get_optional_enabled);
>  struct clk_bulk_devres {
>  	struct clk_bulk_data *clks;
>  	int num_clks;
> +	void (*exit)(int num_clks, const struct clk_bulk_data *clks);
>  };
> 
>  static void devm_clk_bulk_release(struct device *dev, void *res) @@ -182,6
> +183,46 @@ int __must_check devm_clk_bulk_get_all(struct device *dev,  }
> EXPORT_SYMBOL_GPL(devm_clk_bulk_get_all);
> 
> +static void devm_clk_bulk_release_all_enabled(struct device *dev, void
May be devm_clk_bulk_release_all_disable()

Also this is similar to already existing devm_clk_bulk_release_all(), may be you can reuse this function
And add the exit() callback in devm_clk_bulk_release_all()

> +*res) {
> +	struct clk_bulk_devres *devres = res;
> +
> +	if (devres->exit)
> +		devres->exit(devres->num_clks, devres->clks);
> +
> +	clk_bulk_put_all(devres->num_clks, devres->clks); }
> +
> +int __must_check devm_clk_bulk_get_all_enabled(struct device *dev,

May be devm_clk_bulk_get_all_enable() is more suitable

> +				  struct clk_bulk_data **clks, int *num_clks) {
> +	struct clk_bulk_devres *devres;
> +	int ret;
> +
> +	devres = devres_alloc(devm_clk_bulk_release_all_enabled,
> +			      sizeof(*devres), GFP_KERNEL);
> +	if (!devres)
> +		return -ENOMEM;
> +
> +	ret = clk_bulk_get_all(dev, &devres->clks);
> +	if (ret > 0) {
> +		*clks = devres->clks;
> +		devres->num_clks = ret;
> +		*num_clks = ret;
> +		devres_add(dev, devres);
> +	} else {
> +		devres_free(devres);
> +		return ret;
> +	}
> +
> +	ret = clk_bulk_prepare_enable(devres->num_clks, *clks);
> +	if (!ret)
> +		devres->exit = clk_bulk_disable_unprepare;
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(devm_clk_bulk_get_all_enabled);
> +
>  static int devm_clk_match(struct device *dev, void *res, void *data)  {
>  	struct clk **c = res;
> diff --git a/include/linux/clk.h b/include/linux/clk.h index
> 1ef013324237..bf3e9bee5754 100644
> --- a/include/linux/clk.h
> +++ b/include/linux/clk.h
> @@ -438,6 +438,24 @@ int __must_check
> devm_clk_bulk_get_optional(struct device *dev, int num_clks,  int
> __must_check devm_clk_bulk_get_all(struct device *dev,
>  				       struct clk_bulk_data **clks);
> 
> +/**
> + * devm_clk_bulk_get_all_enabled - managed get multiple clk consumers
> and
> + *					enable all clk
> + * @dev: device for clock "consumer"
> + * @clks: pointer to the clk_bulk_data table of consumer
> + * @num_clks: out parameter to store the number of clk_bulk_data
> + *
> + * Returns success (0) or negative errno.
> + *
> + * This helper function allows drivers to get several clk
> + * consumers and enable all of them in one operation with management.
> + * The clks will automatically be disabled and freed when the device
> + * is unbound.
> + */
> +
> +int __must_check devm_clk_bulk_get_all_enabled(struct device *dev,
> +				struct clk_bulk_data **clks, int *num_clks);
> +
>  /**
>   * devm_clk_get - lookup and obtain a managed reference to a clock
> producer.
>   * @dev: device for clock "consumer"
> @@ -960,6 +978,13 @@ static inline int __must_check
> devm_clk_bulk_get_all(struct device *dev,
>  	return 0;
>  }
> 
> +static inline int __must_check devm_clk_bulk_get_all_enabled(struct
> device *dev,
> +				struct clk_bulk_data **clks, int *num_clks) {
> +
> +	return 0;
> +}
> +
>  static inline struct clk *devm_get_clk_from_child(struct device *dev,
>  				struct device_node *np, const char *con_id)
> {
> --
> 2.17.1

Manivannan Sadhasivam Jan. 20, 2024, 3:03 p.m. UTC | #2

On Wed, Jan 10, 2024 at 04:31:14PM +0530, Shradha Todi wrote:
> Provide a managed devm_clk_bulk* wrapper to get and enable all
> bulk clocks in order to simplify drivers that keeps all clocks
> enabled for the time of driver operation.
> 
> Suggested-by: Marek Szyprowski <[e-mail]>
> Signed-off-by: Shradha Todi <[e-mail]>
> ---
>  drivers/clk/clk-devres.c | 41 ++++++++++++++++++++++++++++++++++++++++
>  include/linux/clk.h      | 25 ++++++++++++++++++++++++
>  2 files changed, 66 insertions(+)
> 
> diff --git a/drivers/clk/clk-devres.c b/drivers/clk/clk-devres.c
> index 4fb4fd4b06bd..05b0ff4bc1d4 100644
> --- a/drivers/clk/clk-devres.c
> +++ b/drivers/clk/clk-devres.c
> @@ -102,6 +102,7 @@ EXPORT_SYMBOL_GPL(devm_clk_get_optional_enabled);
>  struct clk_bulk_devres {
>  	struct clk_bulk_data *clks;
>  	int num_clks;
> +	void (*exit)(int num_clks, const struct clk_bulk_data *clks);
>  };
>  
>  static void devm_clk_bulk_release(struct device *dev, void *res)
> @@ -182,6 +183,46 @@ int __must_check devm_clk_bulk_get_all(struct device *dev,
>  }
>  EXPORT_SYMBOL_GPL(devm_clk_bulk_get_all);
>  
> +static void devm_clk_bulk_release_all_enabled(struct device *dev, void *res)
> +{
> +	struct clk_bulk_devres *devres = res;
> +
> +	if (devres->exit)
> +		devres->exit(devres->num_clks, devres->clks);
> +
> +	clk_bulk_put_all(devres->num_clks, devres->clks);
> +}
> +
> +int __must_check devm_clk_bulk_get_all_enabled(struct device *dev,
> +				  struct clk_bulk_data **clks, int *num_clks)

What is the user supposed to do with "num_clks" when you are already handling
the enable part?

> +{
> +	struct clk_bulk_devres *devres;
> +	int ret;
> +
> +	devres = devres_alloc(devm_clk_bulk_release_all_enabled,
> +			      sizeof(*devres), GFP_KERNEL);
> +	if (!devres)
> +		return -ENOMEM;
> +
> +	ret = clk_bulk_get_all(dev, &devres->clks);
> +	if (ret > 0) {
> +		*clks = devres->clks;
> +		devres->num_clks = ret;
> +		*num_clks = ret;
> +		devres_add(dev, devres);

If you move the statements inside this condition to the end of this function,
you could get rid of the exit() callback and directly use
clk_bulk_disable_unprepare() in devm_clk_bulk_release_all_enabled().

> +	} else {
> +		devres_free(devres);
> +		return ret;
> +	}
> +
> +	ret = clk_bulk_prepare_enable(devres->num_clks, *clks);
> +	if (!ret)
> +		devres->exit = clk_bulk_disable_unprepare;

Here you can just do clk_bulk_put_all() and devres_free() directly because you
know that the driver won't proceed after this error.

- Mani

> +
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(devm_clk_bulk_get_all_enabled);
> +
>  static int devm_clk_match(struct device *dev, void *res, void *data)
>  {
>  	struct clk **c = res;
> diff --git a/include/linux/clk.h b/include/linux/clk.h
> index 1ef013324237..bf3e9bee5754 100644
> --- a/include/linux/clk.h
> +++ b/include/linux/clk.h
> @@ -438,6 +438,24 @@ int __must_check devm_clk_bulk_get_optional(struct device *dev, int num_clks,
>  int __must_check devm_clk_bulk_get_all(struct device *dev,
>  				       struct clk_bulk_data **clks);
>  
> +/**
> + * devm_clk_bulk_get_all_enabled - managed get multiple clk consumers and
> + *					enable all clk
> + * @dev: device for clock "consumer"
> + * @clks: pointer to the clk_bulk_data table of consumer
> + * @num_clks: out parameter to store the number of clk_bulk_data
> + *
> + * Returns success (0) or negative errno.
> + *
> + * This helper function allows drivers to get several clk
> + * consumers and enable all of them in one operation with management.
> + * The clks will automatically be disabled and freed when the device
> + * is unbound.
> + */
> +
> +int __must_check devm_clk_bulk_get_all_enabled(struct device *dev,
> +				struct clk_bulk_data **clks, int *num_clks);
> +
>  /**
>   * devm_clk_get - lookup and obtain a managed reference to a clock producer.
>   * @dev: device for clock "consumer"
> @@ -960,6 +978,13 @@ static inline int __must_check devm_clk_bulk_get_all(struct device *dev,
>  	return 0;
>  }
>  
> +static inline int __must_check devm_clk_bulk_get_all_enabled(struct device *dev,
> +				struct clk_bulk_data **clks, int *num_clks)
> +{
> +
> +	return 0;
> +}
> +
>  static inline struct clk *devm_get_clk_from_child(struct device *dev,
>  				struct device_node *np, const char *con_id)
>  {
> -- 
> 2.17.1
>

Shradha Todi Jan. 24, 2024, 6:39 a.m. UTC | #3

> -----Original Message-----
> From: Alim Akhtar <[e-mail]>
> Sent: 10 January 2024 18:01
> To: 'Shradha Todi' <[e-mail]>; [e-mail]; linux-
> [e-mail]; [e-mail]; linux-arm-
> [e-mail]; [e-mail]
> Cc: [e-mail]; [e-mail]; [e-mail];
> [e-mail]; [e-mail]; [e-mail]; [e-mail];
> [e-mail]; [e-mail];
> [e-mail]; [e-mail];
> [e-mail]
> Subject: RE: [PATCH v3 1/2] clk: Provide managed helper to get and enable bulk
> clocks
> 
> Hi Shradha,
> 
> > -----Original Message-----
> > From: Shradha Todi <[e-mail]>
> > Sent: Wednesday, January 10, 2024 4:31 PM
> > To: [e-mail]; [e-mail]; linux-
> > [e-mail]; [e-mail];
> > linux-samsung- [e-mail]
> > Cc: [e-mail]; [e-mail]; [e-mail];
> > [e-mail]; [e-mail]; [e-mail];
> > [e-mail]; [e-mail];
> > [e-mail]; [e-mail];
> > [e-mail]; [e-mail]; Shradha
> > Todi <[e-mail]>
> > Subject: [PATCH v3 1/2] clk: Provide managed helper to get and enable
> > bulk clocks
> >
> > Provide a managed devm_clk_bulk* wrapper to get and enable all bulk
> > clocks in order to simplify drivers that keeps all clocks enabled for
> > the time of driver operation.
> >
> > Suggested-by: Marek Szyprowski <[e-mail]>
> > Signed-off-by: Shradha Todi <[e-mail]>
> > ---
> >  drivers/clk/clk-devres.c | 41
> > ++++++++++++++++++++++++++++++++++++++++
> >  include/linux/clk.h      | 25 ++++++++++++++++++++++++
> >  2 files changed, 66 insertions(+)
> >
> > diff --git a/drivers/clk/clk-devres.c b/drivers/clk/clk-devres.c index
> > 4fb4fd4b06bd..05b0ff4bc1d4 100644
> > --- a/drivers/clk/clk-devres.c
> > +++ b/drivers/clk/clk-devres.c
> > @@ -102,6 +102,7 @@
> > EXPORT_SYMBOL_GPL(devm_clk_get_optional_enabled);
> >  struct clk_bulk_devres {
> >  	struct clk_bulk_data *clks;
> >  	int num_clks;
> > +	void (*exit)(int num_clks, const struct clk_bulk_data *clks);
> >  };
> >
> >  static void devm_clk_bulk_release(struct device *dev, void *res) @@
> > -182,6
> > +183,46 @@ int __must_check devm_clk_bulk_get_all(struct device *dev,
> > +}
> > EXPORT_SYMBOL_GPL(devm_clk_bulk_get_all);
> >
> > +static void devm_clk_bulk_release_all_enabled(struct device *dev,
> > +void
> May be devm_clk_bulk_release_all_disable()
> 

Will change this in the next patchset

> Also this is similar to already existing devm_clk_bulk_release_all(), may be you
> can reuse this function And add the exit() callback in devm_clk_bulk_release_all()
> 

Since I'm planning to remove the exit callback in the next version as suggested by Manivannan, I will have to
go with a new release function

> > +*res) {
> > +	struct clk_bulk_devres *devres = res;
> > +
> > +	if (devres->exit)
> > +		devres->exit(devres->num_clks, devres->clks);
> > +
> > +	clk_bulk_put_all(devres->num_clks, devres->clks); }
> > +
> > +int __must_check devm_clk_bulk_get_all_enabled(struct device *dev,
> 
> May be devm_clk_bulk_get_all_enable() is more suitable
> 

Will take this in the next patchset! Thanks for the review

> > +				  struct clk_bulk_data **clks, int *num_clks) {
> > +	struct clk_bulk_devres *devres;
> > +	int ret;
> > +
> > +	devres = devres_alloc(devm_clk_bulk_release_all_enabled,
> > +			      sizeof(*devres), GFP_KERNEL);
> > +	if (!devres)
> > +		return -ENOMEM;
> > +
> > +	ret = clk_bulk_get_all(dev, &devres->clks);
> > +	if (ret > 0) {
> > +		*clks = devres->clks;
> > +		devres->num_clks = ret;
> > +		*num_clks = ret;
> > +		devres_add(dev, devres);
> > +	} else {
> > +		devres_free(devres);
> > +		return ret;
> > +	}
> > +
> > +	ret = clk_bulk_prepare_enable(devres->num_clks, *clks);
> > +	if (!ret)
> > +		devres->exit = clk_bulk_disable_unprepare;
> > +
> > +	return ret;
> > +}
> > +EXPORT_SYMBOL_GPL(devm_clk_bulk_get_all_enabled);
> > +
> >  static int devm_clk_match(struct device *dev, void *res, void *data)  {
> >  	struct clk **c = res;
> > diff --git a/include/linux/clk.h b/include/linux/clk.h index
> > 1ef013324237..bf3e9bee5754 100644
> > --- a/include/linux/clk.h
> > +++ b/include/linux/clk.h
> > @@ -438,6 +438,24 @@ int __must_check
> > devm_clk_bulk_get_optional(struct device *dev, int num_clks,  int
> > __must_check devm_clk_bulk_get_all(struct device *dev,
> >  				       struct clk_bulk_data **clks);
> >
> > +/**
> > + * devm_clk_bulk_get_all_enabled - managed get multiple clk consumers
> > and
> > + *					enable all clk
> > + * @dev: device for clock "consumer"
> > + * @clks: pointer to the clk_bulk_data table of consumer
> > + * @num_clks: out parameter to store the number of clk_bulk_data
> > + *
> > + * Returns success (0) or negative errno.
> > + *
> > + * This helper function allows drivers to get several clk
> > + * consumers and enable all of them in one operation with management.
> > + * The clks will automatically be disabled and freed when the device
> > + * is unbound.
> > + */
> > +
> > +int __must_check devm_clk_bulk_get_all_enabled(struct device *dev,
> > +				struct clk_bulk_data **clks, int *num_clks);
> > +
> >  /**
> >   * devm_clk_get - lookup and obtain a managed reference to a clock
> > producer.
> >   * @dev: device for clock "consumer"
> > @@ -960,6 +978,13 @@ static inline int __must_check
> > devm_clk_bulk_get_all(struct device *dev,
> >  	return 0;
> >  }
> >
> > +static inline int __must_check devm_clk_bulk_get_all_enabled(struct
> > device *dev,
> > +				struct clk_bulk_data **clks, int *num_clks) {
> > +
> > +	return 0;
> > +}
> > +
> >  static inline struct clk *devm_get_clk_from_child(struct device *dev,
> >  				struct device_node *np, const char *con_id) {
> > --
> > 2.17.1
>

Shradha Todi Jan. 24, 2024, 6:53 a.m. UTC | #4

> -----Original Message-----
> From: Manivannan Sadhasivam <[e-mail]>
> Sent: 20 January 2024 20:33
> To: Shradha Todi <[e-mail]>
> Cc: [e-mail]; [e-mail]; linux-
> [e-mail]; [e-mail]; linux-samsung-
> [e-mail]; [e-mail]; [e-mail];
> [e-mail]; [e-mail]; [e-mail]; [e-mail];
> [e-mail]; [e-mail];
> [e-mail]; [e-mail];
> [e-mail]
> Subject: Re: [PATCH v3 1/2] clk: Provide managed helper to get and enable bulk
> clocks
> 
> On Wed, Jan 10, 2024 at 04:31:14PM +0530, Shradha Todi wrote:
> > Provide a managed devm_clk_bulk* wrapper to get and enable all bulk
> > clocks in order to simplify drivers that keeps all clocks enabled for
> > the time of driver operation.
> >
> > Suggested-by: Marek Szyprowski <[e-mail]>
> > Signed-off-by: Shradha Todi <[e-mail]>
> > ---
> >  drivers/clk/clk-devres.c | 41
> ++++++++++++++++++++++++++++++++++++++++
> >  include/linux/clk.h      | 25 ++++++++++++++++++++++++
> >  2 files changed, 66 insertions(+)
> >
> > diff --git a/drivers/clk/clk-devres.c b/drivers/clk/clk-devres.c index
> > 4fb4fd4b06bd..05b0ff4bc1d4 100644
> > --- a/drivers/clk/clk-devres.c
> > +++ b/drivers/clk/clk-devres.c
> > @@ -102,6 +102,7 @@
> EXPORT_SYMBOL_GPL(devm_clk_get_optional_enabled);
> >  struct clk_bulk_devres {
> >  	struct clk_bulk_data *clks;
> >  	int num_clks;
> > +	void (*exit)(int num_clks, const struct clk_bulk_data *clks);
> >  };
> >
> >  static void devm_clk_bulk_release(struct device *dev, void *res) @@
> > -182,6 +183,46 @@ int __must_check devm_clk_bulk_get_all(struct device
> > *dev,  }  EXPORT_SYMBOL_GPL(devm_clk_bulk_get_all);
> >
> > +static void devm_clk_bulk_release_all_enabled(struct device *dev,
> > +void *res) {
> > +	struct clk_bulk_devres *devres = res;
> > +
> > +	if (devres->exit)
> > +		devres->exit(devres->num_clks, devres->clks);
> > +
> > +	clk_bulk_put_all(devres->num_clks, devres->clks); }
> > +
> > +int __must_check devm_clk_bulk_get_all_enabled(struct device *dev,
> > +				  struct clk_bulk_data **clks, int *num_clks)
> 
> What is the user supposed to do with "num_clks" when you are already handling
> the enable part?
> 

Since the initial clk_bulk_get_all was returning the num_clks value, the thought was to maintain this
as the user might want to have a check in their driver whether x number of clocks were successfully
retrieved and enabled.

> > +{
> > +	struct clk_bulk_devres *devres;
> > +	int ret;
> > +
> > +	devres = devres_alloc(devm_clk_bulk_release_all_enabled,
> > +			      sizeof(*devres), GFP_KERNEL);
> > +	if (!devres)
> > +		return -ENOMEM;
> > +
> > +	ret = clk_bulk_get_all(dev, &devres->clks);
> > +	if (ret > 0) {
> > +		*clks = devres->clks;
> > +		devres->num_clks = ret;
> > +		*num_clks = ret;
> > +		devres_add(dev, devres);
> 
> If you move the statements inside this condition to the end of this function, you
> could get rid of the exit() callback and directly use
> clk_bulk_disable_unprepare() in devm_clk_bulk_release_all_enabled().
> 

Okay! I will change this in the next patchset as suggested

> > +	} else {
> > +		devres_free(devres);
> > +		return ret;
> > +	}
> > +
> > +	ret = clk_bulk_prepare_enable(devres->num_clks, *clks);
> > +	if (!ret)
> > +		devres->exit = clk_bulk_disable_unprepare;
> 
> Here you can just do clk_bulk_put_all() and devres_free() directly because you
> know that the driver won't proceed after this error.
> 
> - Mani
> 

Thanks for the review, Mani. Will change this as suggested!

> > +
> > +	return ret;
> > +}
> > +EXPORT_SYMBOL_GPL(devm_clk_bulk_get_all_enabled);
> > +
> >  static int devm_clk_match(struct device *dev, void *res, void *data)
> > {
> >  	struct clk **c = res;
> > diff --git a/include/linux/clk.h b/include/linux/clk.h index
> > 1ef013324237..bf3e9bee5754 100644
> > --- a/include/linux/clk.h
> > +++ b/include/linux/clk.h
> > @@ -438,6 +438,24 @@ int __must_check
> > devm_clk_bulk_get_optional(struct device *dev, int num_clks,  int
> __must_check devm_clk_bulk_get_all(struct device *dev,
> >  				       struct clk_bulk_data **clks);
> >
> > +/**
> > + * devm_clk_bulk_get_all_enabled - managed get multiple clk consumers and
> > + *					enable all clk
> > + * @dev: device for clock "consumer"
> > + * @clks: pointer to the clk_bulk_data table of consumer
> > + * @num_clks: out parameter to store the number of clk_bulk_data
> > + *
> > + * Returns success (0) or negative errno.
> > + *
> > + * This helper function allows drivers to get several clk
> > + * consumers and enable all of them in one operation with management.
> > + * The clks will automatically be disabled and freed when the device
> > + * is unbound.
> > + */
> > +
> > +int __must_check devm_clk_bulk_get_all_enabled(struct device *dev,
> > +				struct clk_bulk_data **clks, int *num_clks);
> > +
> >  /**
> >   * devm_clk_get - lookup and obtain a managed reference to a clock producer.
> >   * @dev: device for clock "consumer"
> > @@ -960,6 +978,13 @@ static inline int __must_check
> devm_clk_bulk_get_all(struct device *dev,
> >  	return 0;
> >  }
> >
> > +static inline int __must_check devm_clk_bulk_get_all_enabled(struct device
> *dev,
> > +				struct clk_bulk_data **clks, int *num_clks) {
> > +
> > +	return 0;
> > +}
> > +
> >  static inline struct clk *devm_get_clk_from_child(struct device *dev,
> >  				struct device_node *np, const char *con_id)  {
> > --
> > 2.17.1
> >
> 
> --
> மணிவண்ணன் சதாசிவம்

Manivannan Sadhasivam Jan. 24, 2024, 8:43 a.m. UTC | #5

On Wed, Jan 24, 2024 at 12:23:15PM +0530, Shradha Todi wrote:
> 
> 
> > -----Original Message-----
> > From: Manivannan Sadhasivam <[e-mail]>
> > Sent: 20 January 2024 20:33
> > To: Shradha Todi <[e-mail]>
> > Cc: [e-mail]; [e-mail]; linux-
> > [e-mail]; [e-mail]; linux-samsung-
> > [e-mail]; [e-mail]; [e-mail];
> > [e-mail]; [e-mail]; [e-mail]; [e-mail];
> > [e-mail]; [e-mail];
> > [e-mail]; [e-mail];
> > [e-mail]
> > Subject: Re: [PATCH v3 1/2] clk: Provide managed helper to get and enable bulk
> > clocks
> > 
> > On Wed, Jan 10, 2024 at 04:31:14PM +0530, Shradha Todi wrote:
> > > Provide a managed devm_clk_bulk* wrapper to get and enable all bulk
> > > clocks in order to simplify drivers that keeps all clocks enabled for
> > > the time of driver operation.
> > >
> > > Suggested-by: Marek Szyprowski <[e-mail]>
> > > Signed-off-by: Shradha Todi <[e-mail]>
> > > ---
> > >  drivers/clk/clk-devres.c | 41
> > ++++++++++++++++++++++++++++++++++++++++
> > >  include/linux/clk.h      | 25 ++++++++++++++++++++++++
> > >  2 files changed, 66 insertions(+)
> > >
> > > diff --git a/drivers/clk/clk-devres.c b/drivers/clk/clk-devres.c index
> > > 4fb4fd4b06bd..05b0ff4bc1d4 100644
> > > --- a/drivers/clk/clk-devres.c
> > > +++ b/drivers/clk/clk-devres.c
> > > @@ -102,6 +102,7 @@
> > EXPORT_SYMBOL_GPL(devm_clk_get_optional_enabled);
> > >  struct clk_bulk_devres {
> > >  	struct clk_bulk_data *clks;
> > >  	int num_clks;
> > > +	void (*exit)(int num_clks, const struct clk_bulk_data *clks);
> > >  };
> > >
> > >  static void devm_clk_bulk_release(struct device *dev, void *res) @@
> > > -182,6 +183,46 @@ int __must_check devm_clk_bulk_get_all(struct device
> > > *dev,  }  EXPORT_SYMBOL_GPL(devm_clk_bulk_get_all);
> > >
> > > +static void devm_clk_bulk_release_all_enabled(struct device *dev,
> > > +void *res) {
> > > +	struct clk_bulk_devres *devres = res;
> > > +
> > > +	if (devres->exit)
> > > +		devres->exit(devres->num_clks, devres->clks);
> > > +
> > > +	clk_bulk_put_all(devres->num_clks, devres->clks); }
> > > +
> > > +int __must_check devm_clk_bulk_get_all_enabled(struct device *dev,
> > > +				  struct clk_bulk_data **clks, int *num_clks)
> > 
> > What is the user supposed to do with "num_clks" when you are already handling
> > the enable part?
> > 
> 
> Since the initial clk_bulk_get_all was returning the num_clks value, the thought was to maintain this
> as the user might want to have a check in their driver whether x number of clocks were successfully
> retrieved and enabled.
> 

IIUC, the returned clock count is only used for enabling or disabling the
clocks later. Since you are already handling it inside this API, I do not see a
necessity to return the count.

- Mani

Patch

diff --git a/drivers/clk/clk-devres.c b/drivers/clk/clk-devres.c
index 4fb4fd4b06bd..05b0ff4bc1d4 100644
--- a/drivers/clk/clk-devres.c
+++ b/drivers/clk/clk-devres.c
@@ -102,6 +102,7 @@  EXPORT_SYMBOL_GPL(devm_clk_get_optional_enabled);
 struct clk_bulk_devres {
 	struct clk_bulk_data *clks;
 	int num_clks;
+	void (*exit)(int num_clks, const struct clk_bulk_data *clks);
 };
 
 static void devm_clk_bulk_release(struct device *dev, void *res)
@@ -182,6 +183,46 @@  int __must_check devm_clk_bulk_get_all(struct device *dev,
 }
 EXPORT_SYMBOL_GPL(devm_clk_bulk_get_all);
 
+static void devm_clk_bulk_release_all_enabled(struct device *dev, void *res)
+{
+	struct clk_bulk_devres *devres = res;
+
+	if (devres->exit)
+		devres->exit(devres->num_clks, devres->clks);
+
+	clk_bulk_put_all(devres->num_clks, devres->clks);
+}
+
+int __must_check devm_clk_bulk_get_all_enabled(struct device *dev,
+				  struct clk_bulk_data **clks, int *num_clks)
+{
+	struct clk_bulk_devres *devres;
+	int ret;
+
+	devres = devres_alloc(devm_clk_bulk_release_all_enabled,
+			      sizeof(*devres), GFP_KERNEL);
+	if (!devres)
+		return -ENOMEM;
+
+	ret = clk_bulk_get_all(dev, &devres->clks);
+	if (ret > 0) {
+		*clks = devres->clks;
+		devres->num_clks = ret;
+		*num_clks = ret;
+		devres_add(dev, devres);
+	} else {
+		devres_free(devres);
+		return ret;
+	}
+
+	ret = clk_bulk_prepare_enable(devres->num_clks, *clks);
+	if (!ret)
+		devres->exit = clk_bulk_disable_unprepare;
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(devm_clk_bulk_get_all_enabled);
+
 static int devm_clk_match(struct device *dev, void *res, void *data)
 {
 	struct clk **c = res;
diff --git a/include/linux/clk.h b/include/linux/clk.h
index 1ef013324237..bf3e9bee5754 100644
--- a/include/linux/clk.h
+++ b/include/linux/clk.h
@@ -438,6 +438,24 @@  int __must_check devm_clk_bulk_get_optional(struct device *dev, int num_clks,
 int __must_check devm_clk_bulk_get_all(struct device *dev,
 				       struct clk_bulk_data **clks);
 
+/**
+ * devm_clk_bulk_get_all_enabled - managed get multiple clk consumers and
+ *					enable all clk
+ * @dev: device for clock "consumer"
+ * @clks: pointer to the clk_bulk_data table of consumer
+ * @num_clks: out parameter to store the number of clk_bulk_data
+ *
+ * Returns success (0) or negative errno.
+ *
+ * This helper function allows drivers to get several clk
+ * consumers and enable all of them in one operation with management.
+ * The clks will automatically be disabled and freed when the device
+ * is unbound.
+ */
+
+int __must_check devm_clk_bulk_get_all_enabled(struct device *dev,
+				struct clk_bulk_data **clks, int *num_clks);
+
 /**
  * devm_clk_get - lookup and obtain a managed reference to a clock producer.
  * @dev: device for clock "consumer"
@@ -960,6 +978,13 @@  static inline int __must_check devm_clk_bulk_get_all(struct device *dev,
 	return 0;
 }
 
+static inline int __must_check devm_clk_bulk_get_all_enabled(struct device *dev,
+				struct clk_bulk_data **clks, int *num_clks)
+{
+
+	return 0;
+}
+
 static inline struct clk *devm_get_clk_from_child(struct device *dev,
 				struct device_node *np, const char *con_id)
 {