diff mbox

[PATCHv4,1/8] ARM: OMAP: clk: add support for omap_clk_for_each

Message ID 1342189185-5306-2-git-send-email-t-kristo@ti.com (mailing list archive)
State New, archived
Headers show

Commit Message

Tero Kristo July 13, 2012, 2:19 p.m. UTC
This works similarly to e.g. pwrdm_for_each(). Needed by enhanced
usecounting debug functionality that will be added to pm-debug.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@ti.com>
---
 arch/arm/plat-omap/clock.c              |   33 +++++++++++++++++++++++++++++++
 arch/arm/plat-omap/include/plat/clock.h |    2 +
 2 files changed, 35 insertions(+), 0 deletions(-)

Comments

Rajendra Nayak July 16, 2012, 10:04 a.m. UTC | #1
On Friday 13 July 2012 07:49 PM, Tero Kristo wrote:
> This works similarly to e.g. pwrdm_for_each(). Needed by enhanced
> usecounting debug functionality that will be added to pm-debug.

OMAP clock framework has its own debugfs entry (/debug/clock) to expose
usecounts for clocks, so does the COMMON clock framework (/debug/clk).
Maybe there isn't one which dumps usecounts for the complete tree,
instead there is one per each clock node.

I agree having a complete dump of the clock tree usecounts can be
useful, but can we keep it in /debug/clock for now?
The reason I am saying this is because once we move from OMAP clock to
COMMON clock, something like what 'omap_clk_for_each' does will
not be possible anyway. We might have to add the support for
dumping complete tree usecounts into the COMMON clock core.

>
> Signed-off-by: Tero Kristo<t-kristo@ti.com>
> Cc: Paul Walmsley<paul@pwsan.com>
> Cc: Kevin Hilman<khilman@ti.com>
> ---
>   arch/arm/plat-omap/clock.c              |   33 +++++++++++++++++++++++++++++++
>   arch/arm/plat-omap/include/plat/clock.h |    2 +
>   2 files changed, 35 insertions(+), 0 deletions(-)
>
> diff --git a/arch/arm/plat-omap/clock.c b/arch/arm/plat-omap/clock.c
> index 706b7e2..ad9dc59 100644
> --- a/arch/arm/plat-omap/clock.c
> +++ b/arch/arm/plat-omap/clock.c
> @@ -355,6 +355,39 @@ int omap_clk_enable_autoidle_all(void)
>   	return 0;
>   }
>
> +/**
> + * omap_clk_for_each - call a function for each registered clock
> + * @fn: pointer to callback function
> + * @data: void * data to pass to callback function
> + *
> + * Call @fn for each registered clock, passing @data to each function.
> + * @fn must return 0 for success or any other value for failure. If
> + * @fn returns non-zero, the iteration across clocks will stop and
> + * the non-zero return value will be passed to the caller of
> + * omap_clk_for_each(). @fn is called with clockfw_lock held.
> + */
> +int omap_clk_for_each(int (*fn)(struct clk *clk, void *user), void *user)
> +{
> +	struct clk *c;
> +	unsigned long flags;
> +	int ret = 0;
> +
> +	if (!fn)
> +		return -EINVAL;
> +
> +	spin_lock_irqsave(&clockfw_lock, flags);
> +
> +	list_for_each_entry(c,&clocks, node) {
> +		ret = fn(c, user);
> +		if (ret)
> +			break;
> +	}
> +
> +	spin_unlock_irqrestore(&clockfw_lock, flags);
> +
> +	return ret;
> +}
> +
>   int omap_clk_disable_autoidle_all(void)
>   {
>   	struct clk *c;
> diff --git a/arch/arm/plat-omap/include/plat/clock.h b/arch/arm/plat-omap/include/plat/clock.h
> index d0ef57c..998947e 100644
> --- a/arch/arm/plat-omap/include/plat/clock.h
> +++ b/arch/arm/plat-omap/include/plat/clock.h
> @@ -294,6 +294,8 @@ extern void propagate_rate(struct clk *clk);
>   extern void recalculate_root_clocks(void);
>   extern unsigned long followparent_recalc(struct clk *clk);
>   extern void clk_enable_init_clocks(void);
> +extern int omap_clk_for_each(int (*fn)(struct clk *clk, void *user),
> +				void *user);
>   unsigned long omap_fixed_divisor_recalc(struct clk *clk);
>   extern struct clk *omap_clk_get_by_name(const char *name);
>   extern int omap_clk_enable_autoidle_all(void);

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Tero Kristo July 16, 2012, 11:42 a.m. UTC | #2
On Mon, 2012-07-16 at 15:34 +0530, Rajendra Nayak wrote:
> On Friday 13 July 2012 07:49 PM, Tero Kristo wrote:
> > This works similarly to e.g. pwrdm_for_each(). Needed by enhanced
> > usecounting debug functionality that will be added to pm-debug.
> 
> OMAP clock framework has its own debugfs entry (/debug/clock) to expose
> usecounts for clocks, so does the COMMON clock framework (/debug/clk).
> Maybe there isn't one which dumps usecounts for the complete tree,
> instead there is one per each clock node.
> 
> I agree having a complete dump of the clock tree usecounts can be
> useful, but can we keep it in /debug/clock for now?
> The reason I am saying this is because once we move from OMAP clock to
> COMMON clock, something like what 'omap_clk_for_each' does will
> not be possible anyway. We might have to add the support for
> dumping complete tree usecounts into the COMMON clock core.

The main idea behind the dump was to allow dumping of whole clocktree
status during failed suspend. It is not that useful as a debugfs feature
(you can do the same with some scripts on userspace), but this is
available as a side effect from the suspend dump.

-Tero

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diff mbox

Patch

diff --git a/arch/arm/plat-omap/clock.c b/arch/arm/plat-omap/clock.c
index 706b7e2..ad9dc59 100644
--- a/arch/arm/plat-omap/clock.c
+++ b/arch/arm/plat-omap/clock.c
@@ -355,6 +355,39 @@  int omap_clk_enable_autoidle_all(void)
 	return 0;
 }
 
+/**
+ * omap_clk_for_each - call a function for each registered clock
+ * @fn: pointer to callback function
+ * @data: void * data to pass to callback function
+ *
+ * Call @fn for each registered clock, passing @data to each function.
+ * @fn must return 0 for success or any other value for failure. If
+ * @fn returns non-zero, the iteration across clocks will stop and
+ * the non-zero return value will be passed to the caller of
+ * omap_clk_for_each(). @fn is called with clockfw_lock held.
+ */
+int omap_clk_for_each(int (*fn)(struct clk *clk, void *user), void *user)
+{
+	struct clk *c;
+	unsigned long flags;
+	int ret = 0;
+
+	if (!fn)
+		return -EINVAL;
+
+	spin_lock_irqsave(&clockfw_lock, flags);
+
+	list_for_each_entry(c, &clocks, node) {
+		ret = fn(c, user);
+		if (ret)
+			break;
+	}
+
+	spin_unlock_irqrestore(&clockfw_lock, flags);
+
+	return ret;
+}
+
 int omap_clk_disable_autoidle_all(void)
 {
 	struct clk *c;
diff --git a/arch/arm/plat-omap/include/plat/clock.h b/arch/arm/plat-omap/include/plat/clock.h
index d0ef57c..998947e 100644
--- a/arch/arm/plat-omap/include/plat/clock.h
+++ b/arch/arm/plat-omap/include/plat/clock.h
@@ -294,6 +294,8 @@  extern void propagate_rate(struct clk *clk);
 extern void recalculate_root_clocks(void);
 extern unsigned long followparent_recalc(struct clk *clk);
 extern void clk_enable_init_clocks(void);
+extern int omap_clk_for_each(int (*fn)(struct clk *clk, void *user),
+				void *user);
 unsigned long omap_fixed_divisor_recalc(struct clk *clk);
 extern struct clk *omap_clk_get_by_name(const char *name);
 extern int omap_clk_enable_autoidle_all(void);