| Message ID | 87zikjw08i.wl%kuninori.morimoto.gx@renesas.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 11/29, Kuninori Morimoto wrote: > > From: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> > > Current Linux has of_clk_get(), but doesn't have devm_of_clk_get(). > This patch adds it. It is implemeted in clk-devres.c to share > devm_clk_release(). Please add an explanation of why we want this sort of API. The example you gave for audio sound card is useful. We're not going to remember 5 months from now why we did something, so we should put that here instead of digging through mailing list archives. > > Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> > > diff --git a/drivers/clk/clk-devres.c b/drivers/clk/clk-devres.c > index 8f57154..2449b25 100644 > --- a/drivers/clk/clk-devres.c > +++ b/drivers/clk/clk-devres.c > @@ -53,3 +53,24 @@ void devm_clk_put(struct device *dev, struct clk *clk) > WARN_ON(ret); > } > EXPORT_SYMBOL(devm_clk_put); > + > +struct clk *devm_of_clk_get(struct device *dev, > + struct device_node *np, int index) Please call this devm_get_clk_from_child() instead. Also, replace the index argument with a string called con_id. Then call of_clk_get_by_name() instead of of_clk_get(). > +{ > + struct clk **ptr, *clk; > + > + ptr = devres_alloc(devm_clk_release, sizeof(*ptr), GFP_KERNEL); > + if (!ptr) > + return ERR_PTR(-ENOMEM); > + > + clk = of_clk_get(np, index); > + if (!IS_ERR(clk)) { > + *ptr = clk; > + devres_add(dev, ptr); > + } else { > + devres_free(ptr); > + } > + > + return clk; > +} > +EXPORT_SYMBOL(devm_of_clk_get); > diff --git a/include/linux/clk.h b/include/linux/clk.h > index 123c027..7f50c5f 100644 > --- a/include/linux/clk.h > +++ b/include/linux/clk.h > @@ -17,8 +17,9 @@ > #include <linux/notifier.h> > > struct device; > - > struct clk; > +struct device_node; > +struct of_phandle_args; > > /** > * DOC: clk notifier callback types > @@ -249,6 +250,21 @@ static inline void clk_unprepare(struct clk *clk) > struct clk *devm_clk_get(struct device *dev, const char *id); > > /** > + * devm_clk_get - lookup and obtain a managed reference to a clock producer. That doesn't even match the name of the function. > + * @dev: device for clock "consumer" > + * @np: pointer to clock consumer node > + * @index: clock index > + * > + * This function parses the clocks, and uses them to look up the > + * struct clk from the registered list of clock providers by using > + * @np and @index. > + * > + * The clock will automatically be freed when the device is unbound > + * from the bus. > + */ > +struct clk *devm_of_clk_get(struct device *dev, struct device_node *np, int index);
Hi Stephen > > Current Linux has of_clk_get(), but doesn't have devm_of_clk_get(). > > This patch adds it. It is implemeted in clk-devres.c to share > > devm_clk_release(). > > Please add an explanation of why we want this sort of API. The > example you gave for audio sound card is useful. We're not going > to remember 5 months from now why we did something, so we should > put that here instead of digging through mailing list archives. OK, will do > > +struct clk *devm_of_clk_get(struct device *dev, > > + struct device_node *np, int index) > > Please call this devm_get_clk_from_child() instead. Also, replace > the index argument with a string called con_id. Then call > of_clk_get_by_name() instead of of_clk_get(). I guess we want to have _of_ on function name ? devm_get_clk_from_child() ? devm_of_get_clk_from_child ? Best regards --- Kuninori Morimoto
diff --git a/drivers/clk/clk-devres.c b/drivers/clk/clk-devres.c index 8f57154..2449b25 100644 --- a/drivers/clk/clk-devres.c +++ b/drivers/clk/clk-devres.c @@ -53,3 +53,24 @@ void devm_clk_put(struct device *dev, struct clk *clk) WARN_ON(ret); } EXPORT_SYMBOL(devm_clk_put); + +struct clk *devm_of_clk_get(struct device *dev, + struct device_node *np, int index) +{ + struct clk **ptr, *clk; + + ptr = devres_alloc(devm_clk_release, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + clk = of_clk_get(np, index); + if (!IS_ERR(clk)) { + *ptr = clk; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return clk; +} +EXPORT_SYMBOL(devm_of_clk_get); diff --git a/include/linux/clk.h b/include/linux/clk.h index 123c027..7f50c5f 100644 --- a/include/linux/clk.h +++ b/include/linux/clk.h @@ -17,8 +17,9 @@ #include <linux/notifier.h> struct device; - struct clk; +struct device_node; +struct of_phandle_args; /** * DOC: clk notifier callback types @@ -249,6 +250,21 @@ static inline void clk_unprepare(struct clk *clk) struct clk *devm_clk_get(struct device *dev, const char *id); /** + * devm_clk_get - lookup and obtain a managed reference to a clock producer. + * @dev: device for clock "consumer" + * @np: pointer to clock consumer node + * @index: clock index + * + * This function parses the clocks, and uses them to look up the + * struct clk from the registered list of clock providers by using + * @np and @index. + * + * The clock will automatically be freed when the device is unbound + * from the bus. + */ +struct clk *devm_of_clk_get(struct device *dev, struct device_node *np, int index); + +/** * clk_enable - inform the system when the clock source should be running. * @clk: clock source * @@ -432,6 +448,12 @@ static inline struct clk *devm_clk_get(struct device *dev, const char *id) return NULL; } +static inline struct clk *devm_of_clk_get(struct device *dev, + struct device_node *np, int index) +{ + return NULL; +} + static inline void clk_put(struct clk *clk) {} static inline void devm_clk_put(struct device *dev, struct clk *clk) {} @@ -501,9 +523,6 @@ static inline void clk_disable_unprepare(struct clk *clk) clk_unprepare(clk); } -struct device_node; -struct of_phandle_args; - #if defined(CONFIG_OF) && defined(CONFIG_COMMON_CLK) struct clk *of_clk_get(struct device_node *np, int index); struct clk *of_clk_get_by_name(struct device_node *np, const char *name);