linux-kernel - Re: [PATCH v4 07/12] phy: rockchip: samsung-hdptx: Setup TMDS char rate via phy_configure_opts

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250304-turtle-of-serious-aurora-2b0bae@houat>
Date: Tue, 4 Mar 2025 09:15:21 +0100
From: Maxime Ripard <mripard@...nel.org>
To: Cristian Ciocaltea <cristian.ciocaltea@...labora.com>
Cc: Vinod Koul <vkoul@...nel.org>, 
	Kishon Vijay Abraham I <kishon@...nel.org>, Heiko Stuebner <heiko@...ech.de>, 
	Algea Cao <algea.cao@...k-chips.com>, Sandor Yu <Sandor.yu@....com>, 
	Dmitry Baryshkov <dmitry.baryshkov@...aro.org>, kernel@...labora.com, linux-kernel@...r.kernel.org, 
	linux-phy@...ts.infradead.org, linux-arm-kernel@...ts.infradead.org, 
	linux-rockchip@...ts.infradead.org
Subject: Re: [PATCH v4 07/12] phy: rockchip: samsung-hdptx: Setup TMDS char
 rate via phy_configure_opts_hdmi

On Tue, Mar 04, 2025 at 03:44:06AM +0200, Cristian Ciocaltea wrote:
> The current workaround to setup the TMDS character rate relies on the
> unconventional usage of phy_set_bus_width().
> 
> Make use of the recently introduced HDMI PHY configuration API to
> properly handle the setup.  The workaround will be dropped as soon as
> the switch has been completed on both ends.
> 
> Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@...labora.com>
> ---
>  drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c | 54 ++++++++++++++++-------
>  1 file changed, 38 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c b/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c
> index 2bf525514c1991a1299265d12e1e85f66333c604..7e1d1c10758249aa5bbddbdaae0108bba04f30df 100644
> --- a/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c
> +++ b/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c
> @@ -394,6 +394,7 @@ struct rk_hdptx_phy {
>  
>  	int phy_id;
>  	struct phy *phy;
> +	struct phy_configure_opts_hdmi hdmi_cfg;
>  	struct clk_bulk_data *clks;
>  	int nr_clks;
>  	struct reset_control_bulk_data rsts[RST_MAX];
> @@ -1409,19 +1410,25 @@ static int rk_hdptx_dp_aux_init(struct rk_hdptx_phy *hdptx)
>  static int rk_hdptx_phy_power_on(struct phy *phy)
>  {
>  	struct rk_hdptx_phy *hdptx = phy_get_drvdata(phy);
> -	int bus_width = phy_get_bus_width(hdptx->phy);
>  	enum phy_mode mode = phy_get_mode(phy);
> +	unsigned int rate = 0;
>  	int ret, lane;
>  
> -	/*
> -	 * FIXME: Temporary workaround to pass pixel_clk_rate
> -	 * from the HDMI bridge driver until phy_configure_opts_hdmi
> -	 * becomes available in the PHY API.
> -	 */
> -	unsigned int rate = bus_width & 0xfffffff;
> -
> -	dev_dbg(hdptx->dev, "%s bus_width=%x rate=%u\n",
> -		__func__, bus_width, rate);
> +	if (mode != PHY_MODE_DP) {
> +		if (!hdptx->hdmi_cfg.tmds_char_rate) {
> +			/*
> +			 * FIXME: Temporary workaround to setup TMDS char rate
> +			 * from the RK DW HDMI QP bridge driver.
> +			 * Will be removed as soon the switch to the HDMI PHY
> +			 * configuration API has been completed on both ends.
> +			 */
> +			rate = phy_get_bus_width(hdptx->phy) & 0xfffffff;
> +			hdptx->hdmi_cfg.tmds_char_rate = rate * 100;
> +		} else {
> +			rate = hdptx->hdmi_cfg.tmds_char_rate / 100;
> +		}
> +		dev_dbg(hdptx->dev, "%s rate=%u\n", __func__, rate);
> +	}

Some story here, I can't make sense of a variable in hHz. If it's
actually needed and not a bug, this should be very explictly documented.

Maxime

Download attachment "signature.asc" of type "application/pgp-signature" (274 bytes)