[PATCH v4 0/2] phy: rockchip: inno-hdmi: Change TMDS rate handling to configure() ops

[PATCH v4 0/2] phy: rockchip: inno-hdmi: Change TMDS rate handling to configure() ops

[Jonas Karlman]

This series adds support for using phy_validate() and phy_configure()
with this HDMI PHY as an alternative to current in-tree unused way of
using PHY bus width to configure the TMDS character rate.

The only known users that calls phy_set_bus_width() on this PHY are my
out-of-tree HDMI 2.0 patches for Rockchip RK3228/RK3328, i.e. those
originating from LibreELEC (also carried by other distros), the
downstream vendor kernel uses a different implementation that also calls
phy_set_bus_width() on this PHY.

Patch "drm/rockchip: dw_hdmi: Configure HDMI PHY in atomic_mode_set()"
that calls phy_validate() and phy_configure() on this PHY can be found
at [1].

[1] https://lore.kernel.org/dri-devel/20260510183114.1248840-10-jonas@kwiboo.se/

This series is part of a larger multi series effort to:
- phy: rockchip: inno-hdmi: Change TMDS rate handling to configure() ops [v4]
- drm/rockchip: dw_hdmi: Misc cleanup and propagate bus format [v2]
- drm: bridge: dw_hdmi: Misc enable/disable, CEC and EDID cleanup [v7]
- drm/bridge: dw-hdmi: Improve input/output bus format handling
- drm/bridge: dw-hdmi: Convert to a HDMI bridge and use of bridge connector
- drm/bridge: dw-hdmi: Add and use tmds_char_rate_valid() plat data ops
- drm/meson: hdmi: Misc cleanup and use CEC notifier helpers [v1]
- drm/rockchip: dw_hdmi: Enable YCbCr and Deep Color modes
Link to snapshot: https://github.com/Kwiboo/linux-rockchip/commits/next-20260518-rk-hdmi-v5/

Changes in v4:
- Add NULL opts check in validate()
- Only store the opts->hdmi.tmds_char_rate value for later use
- Move comments about expected consumer usage from inline to above the
  functions
Link to v3: https://lore.kernel.org/linux-phy/20260515195512.1757363-1-jonas@kwiboo.se/

Changes in v3:
- Change validate() ops to only validate tmdsclock
- Add comments about expected consumer usage
- Update commit message with a typical call chain
Link to v2: https://lore.kernel.org/linux-phy/20260510095731.1222705-1-jonas@kwiboo.se/

Changes in v2:
- Split into two patches, one that adds new ops and a second that remove
  the old and unused workaround
- Add validate() ops to validate that the TMDS rate is supported
Link to v1: https://lore.kernel.org/linux-phy/20260503172936.194003-1-jonas@kwiboo.se/

Jonas Karlman (2):
  phy: rockchip: inno-hdmi: Add configure() and validate() ops
  phy: rockchip: inno-hdmi: Remove deprecated way to configure TMDS rate

 drivers/phy/rockchip/phy-rockchip-inno-hdmi.c | 71 +++++++++++++++----
 1 file changed, 58 insertions(+), 13 deletions(-)

-- 
2.54.0


-- 
linux-phy mailing list
linux-phy@lists.infradead.org
https://lists.infradead.org/mailman/listinfo/linux-phy

[PATCH v4 1/2] phy: rockchip: inno-hdmi: Add configure() and validate() ops

[Jonas Karlman]

The commit 10ed34d6eaaf ("phy: Add HDMI configuration options")
introduced a way for HDMI PHYs to be configured through the generic
phy_configure() function.

This driver derives the TMDS character rate from the pixel clock and the
PHY bus width setting. However, no in-tree consumer of this PHY has ever
called phy_set_bus_width() to change the TMDS character rate as only
8-bit RGB output is supported by the HDMI display driver.

Add configure() and validate() ops to allow consumers to configure the
TMDS character rate using phy_configure(). Fallback to the deprecated
way of using the PHY bus width to configure the TMDS character rate.

A typical call chain during DRM modeset on a RK3328 device:

  dw_hdmi_rockchip_encoder_atomic_check():
  - inno_hdmi_phy_validate(): pixclock 148500000 tmdsclock 594000000

  dw_hdmi_rockchip_encoder_atomic_mode_set():
  - inno_hdmi_phy_configure(): pixclock 148500000
    - inno_hdmi_phy_validate(): pixclock 148500000 tmdsclock 594000000

  vop_crtc_atomic_enable():
  - inno_hdmi_phy_rk3328_clk_set_rate(): rate 594000000 tmdsclk 594000000
    inno_hdmi_phy_rk3328_clk_set_rate(): pixclock 594000000 tmdsclock 594000000
  - inno_hdmi_phy_rk3328_clk_recalc_rate(): pixclock 594000000 vco 594000000

  dw_hdmi_rockchip_encoder_enable():
  - inno_hdmi_phy_power_on(): Inno HDMI PHY Power On
    - inno_hdmi_phy_rk3328_clk_set_rate(): rate 594000000 tmdsclk 594000000

Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
---
Changes in v4:
- Add NULL opts check in validate()
- Only store the opts->hdmi.tmds_char_rate value for later use
- Move comments about expected consumer usage from inline to above the
  functions
- Indent a set_rate() sub-call in the commit message call chain
Changes in v3:
- Change validate() ops to only validate tmdsclock
- Add comments about expected consumer usage
- Update commit message with a typical call chain
Changes in v2:
- Add validate() ops to validate that the TMDS rate is supported
- Split out parts that remove the old workaround into a separate patch

Patch "drm/rockchip: dw_hdmi: Configure HDMI PHY in atomic_mode_set()"
at [1] adds phy_validate() and phy_configure() calls for this HDMI PHY.

[1] https://lore.kernel.org/dri-devel/20260510183114.1248840-10-jonas@kwiboo.se/
---
 drivers/phy/rockchip/phy-rockchip-inno-hdmi.c | 62 ++++++++++++++++++-
 1 file changed, 61 insertions(+), 1 deletion(-)

diff --git a/drivers/phy/rockchip/phy-rockchip-inno-hdmi.c b/drivers/phy/rockchip/phy-rockchip-inno-hdmi.c
index 1483907413fa..1c43ea700f0e 100644
--- a/drivers/phy/rockchip/phy-rockchip-inno-hdmi.c
+++ b/drivers/phy/rockchip/phy-rockchip-inno-hdmi.c
@@ -245,6 +245,7 @@ struct inno_hdmi_phy {
 	struct clk *phyclk;
 	unsigned long pixclock;
 	unsigned long tmdsclock;
+	unsigned long opts_tmds_char_rate;
 };
 
 struct pre_pll_config {
@@ -554,7 +555,12 @@ static inline void inno_update_bits(struct inno_hdmi_phy *inno, u8 reg,
 static unsigned long inno_hdmi_phy_get_tmdsclk(struct inno_hdmi_phy *inno,
 					       unsigned long rate)
 {
-	int bus_width = phy_get_bus_width(inno->phy);
+	int bus_width;
+
+	if (inno->opts_tmds_char_rate)
+		return inno->opts_tmds_char_rate;
+
+	bus_width = phy_get_bus_width(inno->phy);
 
 	switch (bus_width) {
 	case 4:
@@ -602,6 +608,57 @@ static irqreturn_t inno_hdmi_phy_rk3328_irq(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
+/*
+ * phy_validate() is expected to be called from encoder atomic_check(), before
+ * the hdmiphy pixel clock is known. Without knowing the actual pixel clock, we
+ * cannot do full validation of the configuration. Instead, we do a simple check
+ * that the pre-pll table contains an entry for the requested TMDS char rate.
+ */
+static int inno_hdmi_phy_validate(struct phy *phy, enum phy_mode mode,
+				  int submode, union phy_configure_opts *opts)
+{
+	const struct pre_pll_config *cfg = pre_pll_cfg_table;
+	unsigned long tmdsclock;
+
+	if (!(mode == PHY_MODE_HDMI && submode == PHY_HDMI_MODE_TMDS))
+		return -EINVAL;
+
+	if (!opts)
+		return -EINVAL;
+
+	if (!opts->hdmi.tmds_char_rate || opts->hdmi.tmds_char_rate > 594000000)
+		return -EINVAL;
+
+	tmdsclock = opts->hdmi.tmds_char_rate;
+	for (; cfg->pixclock != 0; cfg++)
+		if (cfg->tmdsclock == tmdsclock)
+			return 0;
+
+	return -EINVAL;
+}
+
+/*
+ * phy_configure() is expected to be called from encoder atomic_set_mode(),
+ * before the hdmiphy pixel clock is known. Store the requested TMDS character
+ * rate, so that it can be used later in power_on() and/or set_rate() when the
+ * pixel clock is known.
+ */
+static int inno_hdmi_phy_configure(struct phy *phy,
+				   union phy_configure_opts *opts)
+{
+	struct inno_hdmi_phy *inno = phy_get_drvdata(phy);
+	int ret;
+
+	ret = inno_hdmi_phy_validate(phy, phy_get_mode(phy),
+				     PHY_HDMI_MODE_TMDS, opts);
+	if (ret)
+		return ret;
+
+	inno->opts_tmds_char_rate = opts->hdmi.tmds_char_rate;
+
+	return 0;
+}
+
 static int inno_hdmi_phy_power_on(struct phy *phy)
 {
 	struct inno_hdmi_phy *inno = phy_get_drvdata(phy);
@@ -670,6 +727,8 @@ static const struct phy_ops inno_hdmi_phy_ops = {
 	.owner = THIS_MODULE,
 	.power_on = inno_hdmi_phy_power_on,
 	.power_off = inno_hdmi_phy_power_off,
+	.configure = inno_hdmi_phy_configure,
+	.validate = inno_hdmi_phy_validate,
 };
 
 static const
@@ -1392,6 +1451,7 @@ static int inno_hdmi_phy_probe(struct platform_device *pdev)
 	}
 
 	phy_set_drvdata(inno->phy, inno);
+	phy_set_mode_ext(inno->phy, PHY_MODE_HDMI, PHY_HDMI_MODE_TMDS);
 	phy_set_bus_width(inno->phy, 8);
 
 	if (inno->plat_data->ops->init) {
-- 
2.54.0


-- 
linux-phy mailing list
linux-phy@lists.infradead.org
https://lists.infradead.org/mailman/listinfo/linux-phy

[PATCH v4 2/2] phy: rockchip: inno-hdmi: Remove deprecated way to configure TMDS rate

[Jonas Karlman]

The TMDS character rate of this PHY is configured using PHY bus width
in downstream vendor kernel and out-of-tree patches, however no in-tree
consumer of this PHY has ever called phy_set_bus_width() to change the
TMDS character rate as currently only 8-bit RGB output is supported by
the HDMI display driver.

The series "Split Generic PHY consumer and provider" clarifies that
phy_set_bus_width() is intended as a provider-only function.

Remove the deprecated unused fallback way to configure TMDS character
rate now that this HDMI PHY support using phy_configure() to configure
the TMDS character rate.

Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
---
v4: No change
v3: No change
v2: New patch, split from original patch
---
 drivers/phy/rockchip/phy-rockchip-inno-hdmi.c | 17 +----------------
 1 file changed, 1 insertion(+), 16 deletions(-)

diff --git a/drivers/phy/rockchip/phy-rockchip-inno-hdmi.c b/drivers/phy/rockchip/phy-rockchip-inno-hdmi.c
index 1c43ea700f0e..c3d257a0f4a6 100644
--- a/drivers/phy/rockchip/phy-rockchip-inno-hdmi.c
+++ b/drivers/phy/rockchip/phy-rockchip-inno-hdmi.c
@@ -555,24 +555,10 @@ static inline void inno_update_bits(struct inno_hdmi_phy *inno, u8 reg,
 static unsigned long inno_hdmi_phy_get_tmdsclk(struct inno_hdmi_phy *inno,
 					       unsigned long rate)
 {
-	int bus_width;
-
 	if (inno->opts_tmds_char_rate)
 		return inno->opts_tmds_char_rate;
 
-	bus_width = phy_get_bus_width(inno->phy);
-
-	switch (bus_width) {
-	case 4:
-	case 5:
-	case 6:
-	case 10:
-	case 12:
-	case 16:
-		return (u64)rate * bus_width / 8;
-	default:
-		return rate;
-	}
+	return rate;
 }
 
 static irqreturn_t inno_hdmi_phy_rk3328_hardirq(int irq, void *dev_id)
@@ -1452,7 +1438,6 @@ static int inno_hdmi_phy_probe(struct platform_device *pdev)
 
 	phy_set_drvdata(inno->phy, inno);
 	phy_set_mode_ext(inno->phy, PHY_MODE_HDMI, PHY_HDMI_MODE_TMDS);
-	phy_set_bus_width(inno->phy, 8);
 
 	if (inno->plat_data->ops->init) {
 		ret = inno->plat_data->ops->init(inno);
-- 
2.54.0


-- 
linux-phy mailing list
linux-phy@lists.infradead.org
https://lists.infradead.org/mailman/listinfo/linux-phy

Re: [PATCH v4 1/2] phy: rockchip: inno-hdmi: Add configure() and validate() ops

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] inno_hdmi_phy_validate() performs an incomplete validation that allows unsupported (pixclock, tmdsclock) combinations to pass DRM's atomic_check, causing fatal failures during atomic_enable.
--

commit 09a1c2d66dc86a8ff3ab2a20274166576f00f813
Author: Jonas Karlman <jonas@kwiboo.se>

phy: rockchip: inno-hdmi: Add configure() and validate() ops

This commit introduces phy_configure() and phy_validate() operations for
the Inno HDMI PHY driver. It uses the TMDS character rate to validate and
configure the PHY, falling back to bus width if needed.

> diff --git a/drivers/phy/rockchip/phy-rockchip-inno-hdmi.c b/drivers/phy/rockchip/phy-rockchip-inno-hdmi.c
> --- a/drivers/phy/rockchip/phy-rockchip-inno-hdmi.c
> +++ b/drivers/phy/rockchip/phy-rockchip-inno-hdmi.c

[ ... ]

> @@ -608,6 +608,57 @@ static irqreturn_t inno_hdmi_phy_rk3328_irq(int irq, void *dev_id)
>  	return IRQ_HANDLED;
>  }
>  
> +/*
> + * phy_validate() is expected to be called from encoder atomic_check(), before
> + * the hdmiphy pixel clock is known. Without knowing the actual pixel clock, we
> + * cannot do full validation of the configuration. Instead, we do a simple check
> + * that the pre-pll table contains an entry for the requested TMDS char rate.
> + */
> +static int inno_hdmi_phy_validate(struct phy *phy, enum phy_mode mode,
> +				  int submode, union phy_configure_opts *opts)
> +{
> +	const struct pre_pll_config *cfg = pre_pll_cfg_table;
> +	unsigned long tmdsclock;
> +
> +	if (!(mode == PHY_MODE_HDMI && submode == PHY_HDMI_MODE_TMDS))
> +		return -EINVAL;
> +
> +	if (!opts)
> +		return -EINVAL;
> +
> +	if (!opts->hdmi.tmds_char_rate || opts->hdmi.tmds_char_rate > 594000000)
> +		return -EINVAL;
> +
> +	tmdsclock = opts->hdmi.tmds_char_rate;
> +	for (; cfg->pixclock != 0; cfg++)
> +		if (cfg->tmdsclock == tmdsclock)
> +			return 0;
> +
> +	return -EINVAL;
> +}

Could this incomplete validation allow unsupported pixclock and tmdsclock
combinations to pass DRM's atomic_check, leading to fatal failures later
during atomic_enable?

The DRM atomic API requires hardware constraints to be verified during
atomic_check. If pixclock is validated independently elsewhere (such as via
clk_round_rate), a mismatched pair might pass both checks.

For example, if a mode requests a pixclock of 54MHz with a 16-bit color depth
(which yields a tmdsclock of 108MHz), atomic_check would pass because 54MHz
exists in the pixclock column and 108MHz exists in the tmdsclock column.

However, later during atomic_enable, clk_set_rate() calls
inno_hdmi_phy_get_pre_pll_cfg() which searches for the exact pair:

inno_hdmi_phy_get_pre_pll_cfg() {
...
	for (; cfg->pixclock != 0; cfg++)
		if (cfg->pixclock == rate && cfg->tmdsclock == tmdsclock)
			break;

	if (cfg->pixclock == 0)
		return ERR_PTR(-EINVAL);
...
}

Since the specific pair 54MHz and 108MHz does not exist in the table together,
it returns -EINVAL, causing the modeset to abort midway and leaving the
display pipeline broken.

Can the exact pixclock and tmdsclock combination be verified here instead,
perhaps by deriving pixclock from opts->hdmi.tmds_char_rate and the color
depth?

[ ... ]

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260518180722.2480799-1-jonas@kwiboo.se?part=1

-- 
linux-phy mailing list
linux-phy@lists.infradead.org
https://lists.infradead.org/mailman/listinfo/linux-phy