[PATCH 2/3] clk: sunxi-ng: a64: keep tcon0 clock rate when pll-video0's rate changes

[Icenowy Zheng]

在 2023-08-07星期一的 11:36 +0200，Frank Oltmanns写道：
> From: Icenowy Zheng <icenowy at aosc.io>
> 
> Notify TCON0 clock (and in consequence PLL-MIPI by
> CLK_SET_RATE_PARENT)
> to reset when PLL-Video0 changes (because of HDMI PHY clk which is a
> child of PLL-Video0 and has CLK_SET_RATE_PARENT set). In this way we
> can
> get clock tree to satisfy both pipelines.

Well for fixing one's patch that contains SoB, use the following
format:

Signed-off-by: A <a at a.local>
[B: fixed something]
Signed-off-by: B <b at b.local>

> ---
>  drivers/clk/sunxi-ng/ccu-sun50i-a64.c | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/drivers/clk/sunxi-ng/ccu-sun50i-a64.c
> b/drivers/clk/sunxi-ng/ccu-sun50i-a64.c
> index ef567775fc95..93beedb0428e 100644
> --- a/drivers/clk/sunxi-ng/ccu-sun50i-a64.c
> +++ b/drivers/clk/sunxi-ng/ccu-sun50i-a64.c
> @@ -943,6 +943,17 @@ static struct ccu_mux_nb sun50i_a64_cpu_nb = {
>         .bypass_index   = 1, /* index of 24 MHz oscillator */
>  };
>  
> +/*
> + * Since PLL-Video0 is an ancestor of both tcon0 and HDMI PYH, tcon0
> clock will
> + * conflict with HDMI PHY clock which is on another display
> pipeline.
> + *
> + * Therefore, a notifier is required to restore the rate of TCON0
> when the rate
> + * of PLL-Video0 changed.
> + */
> +static struct ccu_rate_reset_nb sun50i_a64_pll_video0_reset_tcon0_nb
> = {
> +       .common         = &pll_video0_clk.common,
> +};
> +
>  static int sun50i_a64_ccu_probe(struct platform_device *pdev)
>  {
>         void __iomem *reg;
> @@ -978,6 +989,10 @@ static int sun50i_a64_ccu_probe(struct
> platform_device *pdev)
>         ccu_mux_notifier_register(pll_cpux_clk.common.hw.clk,
>                                   &sun50i_a64_cpu_nb);
>  
> +       /* Reset the rate of TCON0 clock when PLL-VIDEO0 is changed
> */
> +       sun50i_a64_pll_video0_reset_tcon0_nb.target_clk =
> tcon0_clk.common.hw.clk;
> +       ccu_rate_reset_notifier_register(&sun50i_a64_pll_video0_reset
> _tcon0_nb);
> +
>         return 0;
>  }
>  
>