[PATCH v5 13/21] drm/bridge: inno-hdmi: Make the register clock source selectable

[Maud Spierings]

Hi Michal,

Can confirm that this is fixed now! Thanks for integrating this!

Tested-by: Maud Spierings <maud_spierings at murena.io>

Kind regards,
Maud

On 9/29/26 12:31, Michal Wilczynski wrote:
> inno_hdmi_init_hw() drives the register interface from the system clock
> on every platform, by setting v_REG_CLK_SOURCE_SYS unconditionally in
> HDMI_SYS_CTRL.
> 
> That is not right everywhere. On the JH7110 a Framework 13 (fml13v01)
> panel flickers continuously with the system clock selected and behaves
> once the TMDS clock drives the register interface instead. Maud Spierings
> found this by diffing HDMI_SYS_CTRL against the StarFive vendor kernel,
> which leaves the bit clear.
> 
> Add a plat_data flag for it rather than changing the bit for everyone.
> The Rockchip integrations keep the system clock, so this is a no-op for
> them; only a platform that asks for it gets the TMDS clock.
> 
> Reported-by: Maud Spierings <maud_spierings at murena.io>
> Closes: https://lore.kernel.org/all/e780ecb8-918f-4816-99c8-b69b10b25a18@murena.io/
> Signed-off-by: Michal Wilczynski <m.wilczynski at samsung.com>
> ---
>   drivers/gpu/drm/bridge/inno-hdmi.c | 4 +++-
>   include/drm/bridge/inno_hdmi.h     | 2 ++
>   2 files changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/bridge/inno-hdmi.c b/drivers/gpu/drm/bridge/inno-hdmi.c
> index 56f7d41cdae49ae872599a86799412c421158369..db92013a3b1e7c1b6668e9257523a0ca8d2c23d7 100644
> --- a/drivers/gpu/drm/bridge/inno-hdmi.c
> +++ b/drivers/gpu/drm/bridge/inno-hdmi.c
> @@ -580,7 +580,9 @@ static void inno_hdmi_init_hw(struct inno_hdmi *hdmi)
>   	usleep_range(100, 150);
>   
>   	msk = m_REG_CLK_INV | m_REG_CLK_SOURCE | m_POWER | m_INT_POL;
> -	val = v_REG_CLK_INV | v_REG_CLK_SOURCE_SYS | v_PWR_ON | v_INT_POL_HIGH;
> +	val = v_REG_CLK_INV | v_PWR_ON | v_INT_POL_HIGH;
> +	val |= hdmi->plat_data->reg_clk_source_tmds ? v_REG_CLK_SOURCE_TMDS :
> +						      v_REG_CLK_SOURCE_SYS;
>   	hdmi_modb(hdmi, HDMI_SYS_CTRL, msk, val);
>   
>   	inno_hdmi_standby(hdmi);
> diff --git a/include/drm/bridge/inno_hdmi.h b/include/drm/bridge/inno_hdmi.h
> index 1e9974401c39e3773bb339eaec0b45ff1dd9c975..620f035eb9846762ff91cd933b30e07eaeeae8ed 100644
> --- a/include/drm/bridge/inno_hdmi.h
> +++ b/include/drm/bridge/inno_hdmi.h
> @@ -32,6 +32,8 @@ struct inno_hdmi_plat_data {
>   	const struct inno_hdmi_plat_ops *ops;
>   	struct inno_hdmi_phy_config *phy_configs;
>   	struct inno_hdmi_phy_config *default_phy_config;
> +	/* Clock the register interface from the TMDS clock, not the system clock. */
> +	bool reg_clk_source_tmds;
>   };
>   
>   struct inno_hdmi *inno_hdmi_bind(struct device *pdev,
>