diff mbox series

[v4,02/26] clk: sunxi-ng: Add check for minimal rate to NKM PLLs

Message ID 20181113111633.20189-3-jagan@amarulasolutions.com (mailing list archive)
State New, archived
Headers show
Series drm/sun4i: Allwinner A64 MIPI-DSI support | expand

Commit Message

Jagan Teki Nov. 13, 2018, 11:16 a.m. UTC
Some NKM PLLs doesn't work well when their output clock rate is set below
certain rate.

So, add support for minimal rate for relevant PLLs.

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Acked-by: Stephen Boyd <sboyd@kernel.org>
---
 drivers/clk/sunxi-ng/ccu_nkm.c | 3 +++
 drivers/clk/sunxi-ng/ccu_nkm.h | 1 +
 2 files changed, 4 insertions(+)
diff mbox series

Patch

diff --git a/drivers/clk/sunxi-ng/ccu_nkm.c b/drivers/clk/sunxi-ng/ccu_nkm.c
index 841840e35e61..6b5ad990f802 100644
--- a/drivers/clk/sunxi-ng/ccu_nkm.c
+++ b/drivers/clk/sunxi-ng/ccu_nkm.c
@@ -125,6 +125,9 @@  static unsigned long ccu_nkm_round_rate(struct ccu_mux_internal *mux,
 	if (nkm->common.features & CCU_FEATURE_FIXED_POSTDIV)
 		rate *= nkm->fixed_post_div;
 
+	if (rate < nkm->min_rate)
+		return nkm->min_rate;
+
 	ccu_nkm_find_best(*parent_rate, rate, &_nkm);
 
 	rate = *parent_rate * _nkm.n * _nkm.k / _nkm.m;
diff --git a/drivers/clk/sunxi-ng/ccu_nkm.h b/drivers/clk/sunxi-ng/ccu_nkm.h
index cc6efb70a102..ff5bd00f429f 100644
--- a/drivers/clk/sunxi-ng/ccu_nkm.h
+++ b/drivers/clk/sunxi-ng/ccu_nkm.h
@@ -35,6 +35,7 @@  struct ccu_nkm {
 	struct ccu_mux_internal	mux;
 
 	unsigned int		fixed_post_div;
+	unsigned int		min_rate;
 
 	struct ccu_common	common;
 };