# \[PATCH v4 14/20\] clk: starfive: jh7110-vout: Allow pixel clock rate propagation

- From: Michal Wilczynski \<m.wilczynski@samsung.com\>
- Date: 2026-09-15 15:32:42 
- List: linux-phy
- Page: https://ratatoskr.run/linux-phy/2026/09/17580543
- Thread: https://ratatoskr.run/linux-phy/2026/09/17580529/t.md

```text
The dc8200_pix0 and dc8200_pix1 MUXes feed the display controller, and
the rate they carry is ultimately produced by the HDMI PHY, which
registers hdmitx0_pixelclk as a clock provider.

Add CLK_SET_RATE_PARENT to both MUXes so a rate requested on them
reaches that parent, instead of being clamped to whatever rate the
parent already happens to run at.

Co-developed-by: Dominique Belhachemi <redacted>
Signed-off-by: Dominique Belhachemi <redacted>
Reviewed-by: Joshua Peisach <redacted>
Signed-off-by: Michal Wilczynski <m.wilczynski@samsung.com>
---
 drivers/clk/starfive/clk-starfive-jh7110-vout.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/starfive/clk-starfive-jh7110-vout.c b/drivers/clk/starfive/clk-starfive-jh7110-vout.c
index bad20d5d794a72f071b4d547b7304786a8ba9afa..aeba42cd3c44ba205ced52b1826d2d2de82ad78f 100644
--- a/drivers/clk/starfive/clk-starfive-jh7110-vout.c
+++ b/drivers/clk/starfive/clk-starfive-jh7110-vout.c
@@ -40,10 +40,12 @@ static const struct jh71x0_clk_data jh7110_voutclk_data[] = {
 	JH71X0_GATE(JH7110_VOUTCLK_DC8200_AXI, "dc8200_axi", 0, JH7110_VOUTCLK_VOUT_TOP_AXI),
 	JH71X0_GATE(JH7110_VOUTCLK_DC8200_CORE, "dc8200_core", 0, JH7110_VOUTCLK_VOUT_TOP_AXI),
 	JH71X0_GATE(JH7110_VOUTCLK_DC8200_AHB, "dc8200_ahb", 0, JH7110_VOUTCLK_VOUT_TOP_AHB),
-	JH71X0_GMUX(JH7110_VOUTCLK_DC8200_PIX0, "dc8200_pix0", 0, 2,
+	JH71X0_GMUX(JH7110_VOUTCLK_DC8200_PIX0, "dc8200_pix0",
+		    CLK_SET_RATE_PARENT | CLK_SET_RATE_NO_REPARENT, 2,
 		    JH7110_VOUTCLK_DC8200_PIX,
 		    JH7110_VOUTCLK_HDMITX0_PIXELCLK),
-	JH71X0_GMUX(JH7110_VOUTCLK_DC8200_PIX1, "dc8200_pix1", 0, 2,
+	JH71X0_GMUX(JH7110_VOUTCLK_DC8200_PIX1, "dc8200_pix1",
+		    CLK_SET_RATE_PARENT | CLK_SET_RATE_NO_REPARENT, 2,
 		    JH7110_VOUTCLK_DC8200_PIX,
 		    JH7110_VOUTCLK_HDMITX0_PIXELCLK),
 	/* LCD */

-- 
2.34.1


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```
