This commit adds the clk_get_parent_rate() function, which is responsible
for getting the rate of parent clock.
Unfortunately, u-boot's DM support for getting parent is different
(the parent relationship is in udevice) than the one in Common Clock
Framework [CCF] in Linux.
To alleviate this problem - the clk_get_parent_rate() function has been
introduced to clk-uclass.c.
Signed-off-by: Lukasz Majewski
Reviewed-by: Peng Fan
---
Changes in v6: None
Changes in v5:
- Replace ulong with long long (to accommodate large freqs and return
errors)
Changes in v4: None
Changes in v3:
- The rate information is now cached into struct clk field
- The clk_get_parent() is used to get pointer to the parent struct clk
drivers/clk/clk-uclass.c | 22 ++
include/clk.h| 9 +
2 files changed, 31 insertions(+)
diff --git a/drivers/clk/clk-uclass.c b/drivers/clk/clk-uclass.c
index 4346c61eea..899b2dda6f 100644
--- a/drivers/clk/clk-uclass.c
+++ b/drivers/clk/clk-uclass.c
@@ -395,6 +395,28 @@ struct clk *clk_get_parent(struct clk *clk)
return pclk;
}
+long long clk_get_parent_rate(struct clk *clk)
+{
+ const struct clk_ops *ops;
+ struct clk *pclk;
+
+ debug("%s(clk=%p)\n", __func__, clk);
+
+ pclk = clk_get_parent(clk);
+ if (IS_ERR(pclk))
+ return -ENODEV;
+
+ ops = clk_dev_ops(pclk->dev);
+ if (!ops->get_rate)
+ return -ENOSYS;
+
+ /* Read the 'rate' if not already set */
+ if (!pclk->rate)
+ pclk->rate = clk_get_rate(pclk);
+
+ return pclk->rate;
+}
+
ulong clk_set_rate(struct clk *clk, ulong rate)
{
const struct clk_ops *ops = clk_dev_ops(clk->dev);
diff --git a/include/clk.h b/include/clk.h
index e20641ee98..7b2ff8ebe6 100644
--- a/include/clk.h
+++ b/include/clk.h
@@ -268,6 +268,15 @@ ulong clk_get_rate(struct clk *clk);
struct clk *clk_get_parent(struct clk *clk);
/**
+ * clk_get_parent_rate() - Get parent of current clock rate.
+ *
+ * @clk: A clock struct that was previously successfully requested by
+ * clk_request/get_by_*().
+ * @return clock rate in Hz, or -ve error code.
+ */
+long long clk_get_parent_rate(struct clk *clk);
+
+/**
* clk_set_rate() - Set current clock rate.
*
* @clk: A clock struct that was previously successfully requested by
--
2.11.0
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