Re: [PATCH v4 1/3] PM / clock_ops: Add pm_clk_add_clk()

From: Dmitry Torokhov
Date: Thu Nov 06 2014 - 12:31:40 EST


On Thu, Nov 06, 2014 at 03:51:00PM +0200, Grygorii Strashko wrote:
> From: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
>
> The existing pm_clk_add() allows to pass a clock by con_id. However,
> when referring to a specific clock from DT, no con_id is available.
>
> Add pm_clk_add_clk(), which allows to specify the struct clk * directly.
> The will will increment refcount on clock pointer, so the caller has
> to use clk_put() on clock pointer when done.
>
> CC: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
> CC: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
> CC: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
> Reviewed-by: Santosh Shilimkar <santosh.shilimkar@xxxxxx>
> Reviewed-by: Kevin Hilman <khilman@xxxxxxxxxx>
> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> Signed-off-by: Grygorii Strashko <grygorii.strashko@xxxxxx>

Reviewed-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>

> ---
> drivers/base/power/clock_ops.c | 47 +++++++++++++++++++++++++++++++++---------
> include/linux/pm_clock.h | 8 +++++++
> 2 files changed, 45 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/base/power/clock_ops.c b/drivers/base/power/clock_ops.c
> index 7836930..f061eaa 100644
> --- a/drivers/base/power/clock_ops.c
> +++ b/drivers/base/power/clock_ops.c
> @@ -12,6 +12,7 @@
> #include <linux/pm.h>
> #include <linux/pm_clock.h>
> #include <linux/clk.h>
> +#include <linux/clkdev.h>
> #include <linux/slab.h>
> #include <linux/err.h>
>
> @@ -53,7 +54,8 @@ static inline int __pm_clk_enable(struct device *dev, struct clk *clk)
> */
> static void pm_clk_acquire(struct device *dev, struct pm_clock_entry *ce)
> {
> - ce->clk = clk_get(dev, ce->con_id);
> + if (!ce->clk)
> + ce->clk = clk_get(dev, ce->con_id);
> if (IS_ERR(ce->clk)) {
> ce->status = PCE_STATUS_ERROR;
> } else {
> @@ -63,15 +65,8 @@ static void pm_clk_acquire(struct device *dev, struct pm_clock_entry *ce)
> }
> }
>
> -/**
> - * pm_clk_add - Start using a device clock for power management.
> - * @dev: Device whose clock is going to be used for power management.
> - * @con_id: Connection ID of the clock.
> - *
> - * Add the clock represented by @con_id to the list of clocks used for
> - * the power management of @dev.
> - */
> -int pm_clk_add(struct device *dev, const char *con_id)
> +static int __pm_clk_add(struct device *dev, const char *con_id,
> + struct clk *clk)
> {
> struct pm_subsys_data *psd = dev_to_psd(dev);
> struct pm_clock_entry *ce;
> @@ -93,6 +88,12 @@ int pm_clk_add(struct device *dev, const char *con_id)
> kfree(ce);
> return -ENOMEM;
> }
> + } else {
> + if (IS_ERR(ce->clk) || !__clk_get(clk)) {
> + kfree(ce);
> + return -ENOENT;
> + }
> + ce->clk = clk;
> }
>
> pm_clk_acquire(dev, ce);
> @@ -104,6 +105,32 @@ int pm_clk_add(struct device *dev, const char *con_id)
> }
>
> /**
> + * pm_clk_add - Start using a device clock for power management.
> + * @dev: Device whose clock is going to be used for power management.
> + * @con_id: Connection ID of the clock.
> + *
> + * Add the clock represented by @con_id to the list of clocks used for
> + * the power management of @dev.
> + */
> +int pm_clk_add(struct device *dev, const char *con_id)
> +{
> + return __pm_clk_add(dev, con_id, NULL);
> +}
> +
> +/**
> + * pm_clk_add_clk - Start using a device clock for power management.
> + * @dev: Device whose clock is going to be used for power management.
> + * @clk: Clock pointer
> + *
> + * Add the clock to the list of clocks used for the power management of @dev.
> + * It will increment refcount on clock pointer, use clk_put() on it when done.
> + */
> +int pm_clk_add_clk(struct device *dev, struct clk *clk)
> +{
> + return __pm_clk_add(dev, NULL, clk);
> +}
> +
> +/**
> * __pm_clk_remove - Destroy PM clock entry.
> * @ce: PM clock entry to destroy.
> */
> diff --git a/include/linux/pm_clock.h b/include/linux/pm_clock.h
> index 8348866..0b00396 100644
> --- a/include/linux/pm_clock.h
> +++ b/include/linux/pm_clock.h
> @@ -18,6 +18,8 @@ struct pm_clk_notifier_block {
> char *con_ids[];
> };
>
> +struct clk;
> +
> #ifdef CONFIG_PM_CLK
> static inline bool pm_clk_no_clocks(struct device *dev)
> {
> @@ -29,6 +31,7 @@ extern void pm_clk_init(struct device *dev);
> extern int pm_clk_create(struct device *dev);
> extern void pm_clk_destroy(struct device *dev);
> extern int pm_clk_add(struct device *dev, const char *con_id);
> +extern int pm_clk_add_clk(struct device *dev, struct clk *clk);
> extern void pm_clk_remove(struct device *dev, const char *con_id);
> extern int pm_clk_suspend(struct device *dev);
> extern int pm_clk_resume(struct device *dev);
> @@ -51,6 +54,11 @@ static inline int pm_clk_add(struct device *dev, const char *con_id)
> {
> return -EINVAL;
> }
> +
> +static inline int pm_clk_add_clk(struct device *dev, struct clk *clk)
> +{
> + return -EINVAL;
> +}
> static inline void pm_clk_remove(struct device *dev, const char *con_id)
> {
> }
> --
> 1.9.1
>

--
Dmitry
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