diff mbox series

[v4,2/5] clk: sunxi-ng: a64: Set minimum and maximum rate for PLL-MIPI

Message ID 20240310-pinephone-pll-fixes-v4-2-46fc80c83637@oltmanns.dev (mailing list archive)
State Awaiting Upstream, archived
Headers show
Series Pinephone video out fixes (flipping between two frames) | expand

Commit Message

Frank Oltmanns March 10, 2024, 1:21 p.m. UTC
When the Allwinner A64's TCON0 searches the ideal rate for the connected
panel, it may happen that it requests a rate from its parent PLL-MIPI
which PLL-MIPI does not support.

This happens for example on the Olimex TERES-I laptop where TCON0
requests PLL-MIPI to change to a rate of several GHz which causes the
panel to stay blank. It also happens on the pinephone where a rate of
less than 500 MHz is requested which causes instabilities on some
phones.

Set the minimum and maximum rate of Allwinner A64's PLL-MIPI according
to the Allwinner User Manual.

Fixes: ca1170b69968 ("clk: sunxi-ng: a64: force select PLL_MIPI in TCON0 mux")
Reported-by: Diego Roversi <diegor@tiscali.it>
Closes: https://groups.google.com/g/linux-sunxi/c/Rh-Uqqa66bw
Tested-by: Diego Roversi <diegor@tiscali.it>
Cc: stable@vger.kernel.org
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Frank Oltmanns <frank@oltmanns.dev>
---
 drivers/clk/sunxi-ng/ccu-sun50i-a64.c | 2 ++
 1 file changed, 2 insertions(+)

Comments

Jernej Škrabec March 13, 2024, 6:18 p.m. UTC | #1
Dne nedelja, 10. marec 2024 ob 14:21:12 CET je Frank Oltmanns napisal(a):
> When the Allwinner A64's TCON0 searches the ideal rate for the connected
> panel, it may happen that it requests a rate from its parent PLL-MIPI
> which PLL-MIPI does not support.
> 
> This happens for example on the Olimex TERES-I laptop where TCON0
> requests PLL-MIPI to change to a rate of several GHz which causes the
> panel to stay blank. It also happens on the pinephone where a rate of
> less than 500 MHz is requested which causes instabilities on some
> phones.
> 
> Set the minimum and maximum rate of Allwinner A64's PLL-MIPI according
> to the Allwinner User Manual.
> 
> Fixes: ca1170b69968 ("clk: sunxi-ng: a64: force select PLL_MIPI in TCON0 mux")
> Reported-by: Diego Roversi <diegor@tiscali.it>
> Closes: https://groups.google.com/g/linux-sunxi/c/Rh-Uqqa66bw
> Tested-by: Diego Roversi <diegor@tiscali.it>
> Cc: stable@vger.kernel.org
> Reviewed-by: Maxime Ripard <mripard@kernel.org>
> Signed-off-by: Frank Oltmanns <frank@oltmanns.dev>

Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>

Best regards,
Jernej

> ---
>  drivers/clk/sunxi-ng/ccu-sun50i-a64.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/clk/sunxi-ng/ccu-sun50i-a64.c b/drivers/clk/sunxi-ng/ccu-sun50i-a64.c
> index 8951ffc14ff5..6a4b2b9ef30a 100644
> --- a/drivers/clk/sunxi-ng/ccu-sun50i-a64.c
> +++ b/drivers/clk/sunxi-ng/ccu-sun50i-a64.c
> @@ -182,6 +182,8 @@ static struct ccu_nkm pll_mipi_clk = {
>  					      &ccu_nkm_ops,
>  					      CLK_SET_RATE_UNGATE | CLK_SET_RATE_PARENT),
>  		.features	= CCU_FEATURE_CLOSEST_RATE,
> +		.min_rate	= 500000000,
> +		.max_rate	= 1400000000,
>  	},
>  };
>  
> 
>
diff mbox series

Patch

diff --git a/drivers/clk/sunxi-ng/ccu-sun50i-a64.c b/drivers/clk/sunxi-ng/ccu-sun50i-a64.c
index 8951ffc14ff5..6a4b2b9ef30a 100644
--- a/drivers/clk/sunxi-ng/ccu-sun50i-a64.c
+++ b/drivers/clk/sunxi-ng/ccu-sun50i-a64.c
@@ -182,6 +182,8 @@  static struct ccu_nkm pll_mipi_clk = {
 					      &ccu_nkm_ops,
 					      CLK_SET_RATE_UNGATE | CLK_SET_RATE_PARENT),
 		.features	= CCU_FEATURE_CLOSEST_RATE,
+		.min_rate	= 500000000,
+		.max_rate	= 1400000000,
 	},
 };