[RESEND,1/2] clk: Add consumer APIs for discovering possible parent clocks

Commit Message

Crystal Wood June 12, 2016, 3:16 a.m. UTC

From: Scott Wood <[e-mail]>

Commit fc4a05d4b0eb ("clk: Remove unused provider APIs") removed
__clk_get_num_parents() and clk_hw_get_parent_by_index(), leaving only
true provider API versions that operate on struct clk_hw.

qoriq-cpufreq needs these functions in order to determine the options
it has for calling clk_set_parent() and thus populate the cpufreq
table, so revive them as legitimate consumer APIs.

Signed-off-by: Scott Wood <[e-mail]>
---
Previously sent as http://patchwork.ozlabs.org/patch/519803/

Russell, could you please either ACK this or comment, as CLK API
maintainer?

 drivers/clk/clk.c   | 19 +++++++++++++++++++
 include/linux/clk.h | 31 +++++++++++++++++++++++++++++++
 2 files changed, 50 insertions(+)

Comments

kernel test robot June 12, 2016, 3:32 a.m. UTC | #1

Hi,

[auto build test ERROR on clk/clk-next]
[also build test ERROR on v4.7-rc2]
[cannot apply to next-20160609]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Scott-Wood/clk-Add-consumer-APIs-for-discovering-possible-parent-clocks/20160612-112523
base:   https://git.kernel.org/pub/scm/linux/kernel/git/clk/linux.git clk-next
config: i386-tinyconfig (attached as .config)
compiler: gcc-6 (Debian 6.1.1-1) 6.1.1 20160430
reproduce:
        # save the attached .config to linux build tree
        make ARCH=i386 

All errors (new ones prefixed by >>):

   arch/x86/kernel/tsc.o: In function `clk_get_parent_by_index':
>> tsc.c:(.text+0x3e0): multiple definition of `clk_get_parent_by_index'
   arch/x86/kernel/setup.o:setup.c:(.text+0x3): first defined here
   arch/x86/kernel/tsc.o: In function `clk_get_num_parents':
>> tsc.c:(.text+0x3e3): multiple definition of `clk_get_num_parents'
   arch/x86/kernel/setup.o:setup.c:(.text+0x6): first defined here

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

Patch

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index d584004..d61a3fe 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -290,6 +290,12 @@  struct clk_hw *__clk_get_hw(struct clk *clk)
 }
 EXPORT_SYMBOL_GPL(__clk_get_hw);
 
+unsigned int clk_get_num_parents(struct clk *clk)
+{
+	return !clk ? 0 : clk->core->num_parents;
+}
+EXPORT_SYMBOL_GPL(clk_get_num_parents);
+
 unsigned int clk_hw_get_num_parents(const struct clk_hw *hw)
 {
 	return hw->core->num_parents;
@@ -358,6 +364,19 @@  static struct clk_core *clk_core_get_parent_by_index(struct clk_core *core,
 	return core->parents[index];
 }
 
+struct clk *clk_get_parent_by_index(struct clk *clk, unsigned int index)
+{
+	struct clk_core *parent;
+
+	if (!clk)
+		return NULL;
+
+	parent = clk_core_get_parent_by_index(clk->core, index);
+
+	return !parent ? NULL : parent->hw->clk;
+}
+EXPORT_SYMBOL_GPL(clk_get_parent_by_index);
+
 struct clk_hw *
 clk_hw_get_parent_by_index(const struct clk_hw *hw, unsigned int index)
 {
diff --git a/include/linux/clk.h b/include/linux/clk.h
index 0df4a51..937de0e 100644
--- a/include/linux/clk.h
+++ b/include/linux/clk.h
@@ -392,6 +392,26 @@  int clk_set_parent(struct clk *clk, struct clk *parent);
 struct clk *clk_get_parent(struct clk *clk);
 
 /**
+ * clk_get_parent_by_index - get a possible parent clock by index
+ * @clk: clock source
+ * @index: index into the array of possible parents of this clock
+ *
+ * Returns struct clk corresponding to the requested possible
+ * parent clock source, or NULL.
+ */
+struct clk *clk_get_parent_by_index(struct clk *clk,
+				    unsigned int index);
+
+/**
+ * clk_get_num_parents - get number of possible parents
+ * @clk: clock source
+ *
+ * Returns the number of possible parents of this clock,
+ * which can then be enumerated using clk_get_parent_by_index().
+ */
+unsigned int clk_get_num_parents(struct clk *clk);
+
+/**
  * clk_get_sys - get a clock based upon the device name
  * @dev_id: device name
  * @con_id: connection ID
@@ -461,6 +481,17 @@  static inline struct clk *clk_get_parent(struct clk *clk)
 	return NULL;
 }
 
+struct clk *clk_get_parent_by_index(struct clk *clk,
+				    unsigned int index)
+{
+	return NULL;
+}
+
+unsigned int clk_get_num_parents(struct clk *clk)
+{
+	return 0;
+}
+
 #endif
 
 /* clk_prepare_enable helps cases using clk_enable in non-atomic context. */