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authorMike Turquette <mturquette@linaro.org>2012-03-26 22:51:34 +0400
committerMike Turquette <mturquette@linaro.org>2012-04-25 03:37:37 +0400
commit5654dc94f872f823aa13941a8fdba69a3feca39c (patch)
tree26a6f75f8adafa596025ab81eb8cb48c1702bb3e /drivers/clk/clk.c
parent66f75a5d028beaf67c931435fdc3e7823125730c (diff)
downloadlinux-5654dc94f872f823aa13941a8fdba69a3feca39c.tar.xz
clk: core: correct clk_set_rate kerneldoc
Remove old and misleading documentation from the previous clk_set_rate implementaion. Reported-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Mike Turquette <mturquette@linaro.org>
Diffstat (limited to 'drivers/clk/clk.c')
-rw-r--r--drivers/clk/clk.c41
1 files changed, 11 insertions, 30 deletions
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 9cf6f59e3e19..3ed36d3056de 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -859,38 +859,19 @@ static void clk_change_rate(struct clk *clk)
* @clk: the clk whose rate is being changed
* @rate: the new rate for clk
*
- * In the simplest case clk_set_rate will only change the rate of clk.
+ * In the simplest case clk_set_rate will only adjust the rate of clk.
*
- * If clk has the CLK_SET_RATE_GATE flag set and it is enabled this call
- * will fail; only when the clk is disabled will it be able to change
- * its rate.
+ * Setting the CLK_SET_RATE_PARENT flag allows the rate change operation to
+ * propagate up to clk's parent; whether or not this happens depends on the
+ * outcome of clk's .round_rate implementation. If *parent_rate is unchanged
+ * after calling .round_rate then upstream parent propagation is ignored. If
+ * *parent_rate comes back with a new rate for clk's parent then we propagate
+ * up to clk's parent and set it's rate. Upward propagation will continue
+ * until either a clk does not support the CLK_SET_RATE_PARENT flag or
+ * .round_rate stops requesting changes to clk's parent_rate.
*
- * Setting the CLK_SET_RATE_PARENT flag allows clk_set_rate to
- * recursively propagate up to clk's parent; whether or not this happens
- * depends on the outcome of clk's .round_rate implementation. If
- * *parent_rate is 0 after calling .round_rate then upstream parent
- * propagation is ignored. If *parent_rate comes back with a new rate
- * for clk's parent then we propagate up to clk's parent and set it's
- * rate. Upward propagation will continue until either a clk does not
- * support the CLK_SET_RATE_PARENT flag or .round_rate stops requesting
- * changes to clk's parent_rate. If there is a failure during upstream
- * propagation then clk_set_rate will unwind and restore each clk's rate
- * that had been successfully changed. Afterwards a rate change abort
- * notification will be propagated downstream, starting from the clk
- * that failed.
- *
- * At the end of all of the rate setting, clk_set_rate internally calls
- * __clk_recalc_rates and propagates the rate changes downstream,
- * starting from the highest clk whose rate was changed. This has the
- * added benefit of propagating post-rate change notifiers.
- *
- * Note that while post-rate change and rate change abort notifications
- * are guaranteed to be sent to a clk only once per call to
- * clk_set_rate, pre-change notifications will be sent for every clk
- * whose rate is changed. Stacking pre-change notifications is noisy
- * for the drivers subscribed to them, but this allows drivers to react
- * to intermediate clk rate changes up until the point where the final
- * rate is achieved at the end of upstream propagation.
+ * Rate changes are accomplished via tree traversal that also recalculates the
+ * rates for the clocks and fires off POST_RATE_CHANGE notifiers.
*
* Returns 0 on success, -EERROR otherwise.
*/