[PATCH v2 0/3] normalize clk API for older platforms

[Arnd Bergmann]

Based on the earlier feedback so far, I have split out the patch
per platform, improved the davinci implementation, dropped both
ep93xx (which has a proper implementation coming) and mmp (which
is dead code anyway), and decided to do the sa1100 implementation
differnently (without warning).

Arnd

Arnd Bergmann (3):
ARM: davinci: normalize clk API
ARM: sa1100: normalize clk API
ARM: w90x900: normalize clk API

arch/arm/mach-davinci/clock.c | 9 +++++++++
arch/arm/mach-sa1100/clock.c | 25 +++++++++++++++++++++++++
arch/arm/mach-w90x900/clock.c | 29 +++++++++++++++++++++++++++++
3 files changed, 63 insertions(+)

[Arnd Bergmann]

davinci still has its own clk implementation, but lacks
a clk_get_parent() helper, which can lead to link errors
in randconfig builds.

This adds the usual implementation.

Acked-by: Sekhar Nori <***@ti.com>
Signed-off-by: Arnd Bergmann <***@arndb.de>
---
arch/arm/mach-davinci/clock.c | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/arch/arm/mach-davinci/clock.c b/arch/arm/mach-davinci/clock.c
index f5dce9b4e617..f77a4f766050 100644
--- a/arch/arm/mach-davinci/clock.c
+++ b/arch/arm/mach-davinci/clock.c
@@ -218,6 +218,15 @@ int clk_set_parent(struct clk *clk, struct clk *parent)
}
EXPORT_SYMBOL(clk_set_parent);

+struct clk *clk_get_parent(struct clk *clk)
+{
+ if (!clk)
+ return NULL;
+
+ return clk->parent;
+}
+EXPORT_SYMBOL(clk_get_parent);
+
int clk_register(struct clk *clk)
{
if (clk == NULL || IS_ERR(clk))

[Arnd Bergmann]

sa1100 provides its own variant of the clk API rather than using the
generic COMMON_CLK API. This generally works, but it causes some link
errors with drivers using the clk_set_rate, clk_get_parent, clk_set_parent
or clk_round_rate functions when a platform lacks those interfaces.

This adds trivial stub implementations for each of them, based on
the behavior of the COMMON_CLK implementation:

- set_rate() and set_parent() report success without doing anything
- round_rate() returns the clk rate
- get_parent() returns NULL.

This adds the minimal bloat and should do the right thing for
the simple clock hardware in this SoC.

Signed-off-by: Arnd Bergmann <***@arndb.de>
---
arch/arm/mach-sa1100/clock.c | 25 +++++++++++++++++++++++++
1 file changed, 25 insertions(+)

diff --git a/arch/arm/mach-sa1100/clock.c b/arch/arm/mach-sa1100/clock.c
index 0db46895c82a..7d52cd97d96e 100644
--- a/arch/arm/mach-sa1100/clock.c
+++ b/arch/arm/mach-sa1100/clock.c
@@ -35,6 +35,31 @@ struct clk clk_##_name = { \

static DEFINE_SPINLOCK(clocks_lock);

+/* Dummy clk routine to build generic kernel parts that may be using them */
+long clk_round_rate(struct clk *clk, unsigned long rate)
+{
+ return clk_get_rate(clk);
+}
+EXPORT_SYMBOL(clk_round_rate);
+
+int clk_set_rate(struct clk *clk, unsigned long rate)
+{
+ return 0;
+}
+EXPORT_SYMBOL(clk_set_rate);
+
+int clk_set_parent(struct clk *clk, struct clk *parent)
+{
+ return 0;
+}
+EXPORT_SYMBOL(clk_set_parent);
+
+struct clk *clk_get_parent(struct clk *clk)
+{
+ return NULL;
+}
+EXPORT_SYMBOL(clk_get_parent);
+
static void clk_gpio27_enable(struct clk *clk)
{
/*

[Arnd Bergmann]

w90x900 still provides its own variant of the clk API rather than using
the generic COMMON_CLK API. This generally works, but it causes some link
errors with drivers using the clk_set_rate, clk_get_parent, clk_set_parent
or clk_round_rate functions when a platform lacks those interfaces.

This adds empty stub implementations for each of them, and I don't even
try to do something useful here but instead just print a WARN() message
to make it obvious what is going on if they ever end up being called.

The drivers that call these won't be used on these platforms (otherwise
we'd get a link error today), so the added code is harmless bloat and
will warn about accidental use.

A while ago there was a proposal to change w90x900 to use the common-clk
implementation, which would be the way it should be handled properly.

Signed-off-by: Arnd Bergmann <***@arndb.de>
---
arch/arm/mach-w90x900/clock.c | 29 +++++++++++++++++++++++++++++
1 file changed, 29 insertions(+)

diff --git a/arch/arm/mach-w90x900/clock.c b/arch/arm/mach-w90x900/clock.c
index ac6fd1a2cb59..3f93fac98d97 100644
--- a/arch/arm/mach-w90x900/clock.c
+++ b/arch/arm/mach-w90x900/clock.c
@@ -93,3 +93,32 @@ void nuc900_subclk_enable(struct clk *clk, int enable)

__raw_writel(clken, W90X900_VA_CLKPWR + SUBCLK);
}
+
+/* dummy functions, should not be called */
+long clk_round_rate(struct clk *clk, unsigned long rate)
+{
+ WARN_ON(clk);
+ return 0;
+}
+EXPORT_SYMBOL(clk_round_rate);
+
+int clk_set_rate(struct clk *clk, unsigned long rate)
+{
+ WARN_ON(clk);
+ return 0;
+}
+EXPORT_SYMBOL(clk_set_rate);
+
+int clk_set_parent(struct clk *clk, struct clk *parent)
+{
+ WARN_ON(clk);
+ return 0;
+}
+EXPORT_SYMBOL(clk_set_parent);
+
+struct clk *clk_get_parent(struct clk *clk)
+{
+ WARN_ON(clk);
+ return NULL;
+}
+EXPORT_SYMBOL(clk_get_parent);