[PATCH 4.9 64/88] clk: sunxi-ng: mp: Adjust parent rate for pre-dividers

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Chen-Yu Tsai <wens@xxxxxxxx>

commit ac8616e4c81dded650dfade49a7da283565d37ce upstream.

The MP style clocks support an mux with pre-dividers. While the driver
correctly accounted for them in the .determine_rate callback, it did
not in the .recalc_rate and .set_rate callbacks.

This means when calculating the factors in the .set_rate callback, they
would be off by a factor of the active pre-divider. Same goes for
reading back the clock rate after it is set.

Fixes: 2ab836db5097 ("clk: sunxi-ng: Add M-P factor clock support")
Signed-off-by: Chen-Yu Tsai <wens@xxxxxxxx>
Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/clk/sunxi-ng/ccu_mp.c |    8 ++++++++
 1 file changed, 8 insertions(+)

--- a/drivers/clk/sunxi-ng/ccu_mp.c
+++ b/drivers/clk/sunxi-ng/ccu_mp.c
@@ -85,6 +85,10 @@ static unsigned long ccu_mp_recalc_rate(
 	unsigned int m, p;
 	u32 reg;
 
+	/* Adjust parent_rate according to pre-dividers */
+	ccu_mux_helper_adjust_parent_for_prediv(&cmp->common, &cmp->mux,
+						-1, &parent_rate);
+
 	reg = readl(cmp->common.base + cmp->common.reg);
 
 	m = reg >> cmp->m.shift;
@@ -114,6 +118,10 @@ static int ccu_mp_set_rate(struct clk_hw
 	unsigned int m, p;
 	u32 reg;
 
+	/* Adjust parent_rate according to pre-dividers */
+	ccu_mux_helper_adjust_parent_for_prediv(&cmp->common, &cmp->mux,
+						-1, &parent_rate);
+
 	max_m = cmp->m.max ?: 1 << cmp->m.width;
 	max_p = cmp->p.max ?: 1 << ((1 << cmp->p.width) - 1);