[PATCH 0/4] Config mipi tx drive current and impedance

[PATCH 0/4] Config mipi tx drive current and impedance

[Jitao Shi]

Changes in this patch:
 - add the mipitx driving current control.
 - config the mipitx impedance with calibration data in nvmem.

Jitao Shi (4):
  dt-binds: display: mediatek: add property to control mipi tx drive
    current
  dt-binds: display: mediatek: get mipitx calibration data from nvmem
  drm/mediatek: add the mipitx driving control
  drm/mediatek: config mipitx impedance with calibration data

 .../display/mediatek/mediatek,dsi.txt         |  9 +++
 drivers/gpu/drm/mediatek/mtk_mipi_tx.c        |  6 ++
 drivers/gpu/drm/mediatek/mtk_mipi_tx.h        |  2 +
 drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c | 70 +++++++++++++++++++
 4 files changed, 87 insertions(+)

-- 
2.21.0
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[PATCH 1/4] dt-binds: display: mediatek: add property to control mipi tx drive current

[Jitao Shi]

Add a property to control mipi tx drive current:
"mipitx-current-drive"

Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
---
 .../devicetree/bindings/display/mediatek/mediatek,dsi.txt     | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.txt b/Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.txt
index a19a6cc375ed..780201ddcd5c 100644
--- a/Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.txt
+++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.txt
@@ -33,6 +33,9 @@ Required properties:
 - #clock-cells: must be <0>;
 - #phy-cells: must be <0>.
 
+Optional properties:
+- mipitx-current-drive: adjust driving current, should be 1 ~ 0xF
+
 Example:
 
 mipi_tx0: mipi-dphy@10215000 {
@@ -42,6 +45,7 @@ mipi_tx0: mipi-dphy@10215000 {
 	clock-output-names = "mipi_tx0_pll";
 	#clock-cells = <0>;
 	#phy-cells = <0>;
+	mipitx-current-drive = <0x8>;
 };
 
 dsi0: dsi@1401b000 {
-- 
2.21.0
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[PATCH 2/4] dt-binds: display: mediatek: get mipitx calibration data from nvmem

[Jitao Shi]

Add properties to get get mipitx calibration data.

Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
---
 .../devicetree/bindings/display/mediatek/mediatek,dsi.txt    | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.txt b/Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.txt
index 780201ddcd5c..7f12eb729791 100644
--- a/Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.txt
+++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.txt
@@ -34,6 +34,9 @@ Required properties:
 - #phy-cells: must be <0>.
 
 Optional properties:
+- nvmem-cells: A phandle to the calibration data provided by a nvmem device. If
+               unspecified default values shall be used.
+- nvmem-cell-names: Should be "calibration-data"
 - mipitx-current-drive: adjust driving current, should be 1 ~ 0xF
 
 Example:
@@ -45,6 +48,8 @@ mipi_tx0: mipi-dphy@10215000 {
 	clock-output-names = "mipi_tx0_pll";
 	#clock-cells = <0>;
 	#phy-cells = <0>;
+	nvmem-cells= <&mipi_tx_calibration>;
+	nvmem-cell-names = "calibration-data";
 	mipitx-current-drive = <0x8>;
 };
 
-- 
2.21.0
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[PATCH 3/4] drm/mediatek: add the mipitx driving control

[Jitao Shi]

Add a property in device tree to control the driving by different
board.

Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
---
 drivers/gpu/drm/mediatek/mtk_mipi_tx.c        | 6 ++++++
 drivers/gpu/drm/mediatek/mtk_mipi_tx.h        | 1 +
 drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c | 7 +++++++
 3 files changed, 14 insertions(+)

diff --git a/drivers/gpu/drm/mediatek/mtk_mipi_tx.c b/drivers/gpu/drm/mediatek/mtk_mipi_tx.c
index e4d34484ecc8..ec8406c86bfb 100644
--- a/drivers/gpu/drm/mediatek/mtk_mipi_tx.c
+++ b/drivers/gpu/drm/mediatek/mtk_mipi_tx.c
@@ -125,6 +125,12 @@ static int mtk_mipi_tx_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	ret = of_property_read_u32(dev->of_node, "mipitx-current-drive",
+				   &mipi_tx->mipitx_drive);
+	/* If can't get the "mipi_tx->mipitx_drive", set it default 0x8 */
+	if (ret < 0)
+		mipi_tx->mipitx_drive = 0x8;
+
 	ref_clk_name = __clk_get_name(ref_clk);
 
 	ret = of_property_read_string(dev->of_node, "clock-output-names",
diff --git a/drivers/gpu/drm/mediatek/mtk_mipi_tx.h b/drivers/gpu/drm/mediatek/mtk_mipi_tx.h
index 413f35d86219..eea44327fe9f 100644
--- a/drivers/gpu/drm/mediatek/mtk_mipi_tx.h
+++ b/drivers/gpu/drm/mediatek/mtk_mipi_tx.h
@@ -27,6 +27,7 @@ struct mtk_mipi_tx {
 	struct device *dev;
 	void __iomem *regs;
 	u32 data_rate;
+	u32 mipitx_drive;
 	const struct mtk_mipitx_data *driver_data;
 	struct clk_hw pll_hw;
 	struct clk *pll;
diff --git a/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c b/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c
index 91f08a351fd0..124fdf95f1e5 100644
--- a/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c
+++ b/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c
@@ -17,6 +17,9 @@
 #define RG_DSI_BG_CORE_EN		BIT(7)
 #define RG_DSI_PAD_TIEL_SEL		BIT(8)
 
+#define MIPITX_VOLTAGE_SEL	0x0010
+#define RG_DSI_HSTX_LDO_REF_SEL		(0xf << 6)
+
 #define MIPITX_PLL_PWR		0x0028
 #define MIPITX_PLL_CON0		0x002c
 #define MIPITX_PLL_CON1		0x0030
@@ -123,6 +126,10 @@ static void mtk_mipi_tx_power_on_signal(struct phy *phy)
 	mtk_mipi_tx_clear_bits(mipi_tx, MIPITX_D3_SW_CTL_EN, DSI_SW_CTL_EN);
 	mtk_mipi_tx_clear_bits(mipi_tx, MIPITX_CK_SW_CTL_EN, DSI_SW_CTL_EN);
 
+	mtk_mipi_tx_update_bits(mipi_tx, MIPITX_VOLTAGE_SEL,
+				RG_DSI_HSTX_LDO_REF_SEL,
+				mipi_tx->mipitx_drive << 6);
+
 	mtk_mipi_tx_set_bits(mipi_tx, MIPITX_CK_CKMODE_EN, DSI_CK_CKMODE_EN);
 }
 
-- 
2.21.0
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[PATCH 4/4] drm/mediatek: config mipitx impedance with calibration data

[Jitao Shi]

Read calibration data from nvmem, and config mipitx impedance with
calibration data to make sure their impedance are 100ohm.

Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
---
 drivers/gpu/drm/mediatek/mtk_mipi_tx.h        |  1 +
 drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c | 63 +++++++++++++++++++
 2 files changed, 64 insertions(+)

diff --git a/drivers/gpu/drm/mediatek/mtk_mipi_tx.h b/drivers/gpu/drm/mediatek/mtk_mipi_tx.h
index eea44327fe9f..a1b6292145de 100644
--- a/drivers/gpu/drm/mediatek/mtk_mipi_tx.h
+++ b/drivers/gpu/drm/mediatek/mtk_mipi_tx.h
@@ -28,6 +28,7 @@ struct mtk_mipi_tx {
 	void __iomem *regs;
 	u32 data_rate;
 	u32 mipitx_drive;
+	u32 rt_code[5];
 	const struct mtk_mipitx_data *driver_data;
 	struct clk_hw pll_hw;
 	struct clk *pll;
diff --git a/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c b/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c
index 124fdf95f1e5..f624516944bb 100644
--- a/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c
+++ b/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c
@@ -5,6 +5,8 @@
  */
 
 #include "mtk_mipi_tx.h"
+#include <linux/nvmem-consumer.h>
+#include <linux/slab.h>
 
 #define MIPITX_LANE_CON		0x000c
 #define RG_DSI_CPHY_T1DRV_EN		BIT(0)
@@ -28,6 +30,7 @@
 #define MIPITX_PLL_CON4		0x003c
 #define RG_DSI_PLL_IBIAS		(3 << 10)
 
+#define MIPITX_D2P_RTCODE	0x0100
 #define MIPITX_D2_SW_CTL_EN	0x0144
 #define MIPITX_D0_SW_CTL_EN	0x0244
 #define MIPITX_CK_CKMODE_EN	0x0328
@@ -108,6 +111,64 @@ static const struct clk_ops mtk_mipi_tx_pll_ops = {
 	.recalc_rate = mtk_mipi_tx_pll_recalc_rate,
 };
 
+static int mtk_mipi_tx_config_calibration_data(struct mtk_mipi_tx *mipi_tx)
+{
+	u32 *buf = NULL;
+	int i, j;
+	struct nvmem_cell *cell;
+	struct device *dev = mipi_tx->dev;
+	size_t len;
+
+	cell = nvmem_cell_get(dev, "calibration-data");
+	if (IS_ERR(cell)) {
+		dev_warn(dev, "nvmem_cell_get fail\n");
+		return -EINVAL;
+	}
+
+	buf = (u32 *)nvmem_cell_read(cell, &len);
+
+	nvmem_cell_put(cell);
+
+	if (IS_ERR(buf)) {
+		dev_warn(dev, "can't get data\n");
+		return -EINVAL;
+	}
+
+	if (len < 3 * sizeof(u32)) {
+		dev_warn(dev, "invalid calibration data\n");
+		kfree(buf);
+		return -EINVAL;
+	}
+
+	mipi_tx->rt_code[0] = ((buf[0] >> 6 & 0x1F) << 5) |
+			      (buf[0] >> 11 & 0x1F);
+	mipi_tx->rt_code[1] = ((buf[1] >> 27 & 0x1F) << 5) |
+			      (buf[0] >> 1 & 0x1F);
+	mipi_tx->rt_code[2] = ((buf[1] >> 17 & 0x1F) << 5) |
+			      (buf[1] >> 22 & 0x1F);
+	mipi_tx->rt_code[3] = ((buf[1] >> 7 & 0x1F) << 5) |
+			      (buf[1] >> 12 & 0x1F);
+	mipi_tx->rt_code[4] = ((buf[2] >> 27 & 0x1F) << 5) |
+			      (buf[1] >> 2 & 0x1F);
+
+	for (i = 0; i < 5; i++) {
+		if ((mipi_tx->rt_code[i] & 0x1F) == 0)
+			mipi_tx->rt_code[i] |= 0x10;
+
+		if ((mipi_tx->rt_code[i] >> 5 & 0x1F) == 0)
+			mipi_tx->rt_code[i] |= 0x10 << 5;
+
+		for (j = 0; j < 10; j++) {
+			mtk_mipi_tx_update_bits(mipi_tx,
+				MIPITX_D2P_RTCODE * (i + 1) + j * 4,
+				1, mipi_tx->rt_code[i] >> j & 1);
+		}
+	}
+
+	kfree(buf);
+	return 0;
+}
+
 static void mtk_mipi_tx_power_on_signal(struct phy *phy)
 {
 	struct mtk_mipi_tx *mipi_tx = phy_get_drvdata(phy);
@@ -130,6 +191,8 @@ static void mtk_mipi_tx_power_on_signal(struct phy *phy)
 				RG_DSI_HSTX_LDO_REF_SEL,
 				mipi_tx->mipitx_drive << 6);
 
+	mtk_mipi_tx_config_calibration_data(mipi_tx);
+
 	mtk_mipi_tx_set_bits(mipi_tx, MIPITX_CK_CKMODE_EN, DSI_CK_CKMODE_EN);
 }
 
-- 
2.21.0
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Re: [PATCH 1/4] dt-binds: display: mediatek: add property to control mipi tx drive current

[CK Hu]

Hi, Jitao:

On Mon, 2019-12-16 at 16:29 +0800, Jitao Shi wrote:
> Add a property to control mipi tx drive current:
> "mipitx-current-drive"
> 
> Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
> ---
>  .../devicetree/bindings/display/mediatek/mediatek,dsi.txt     | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.txt b/Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.txt
> index a19a6cc375ed..780201ddcd5c 100644
> --- a/Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.txt
> +++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.txt
> @@ -33,6 +33,9 @@ Required properties:
>  - #clock-cells: must be <0>;
>  - #phy-cells: must be <0>.
>  
> +Optional properties:
> +- mipitx-current-drive: adjust driving current, should be 1 ~ 0xF
> +

In "[PATCH 3/4] drm/mediatek: add the mipitx driving control" [1], I see
that you actually control a register its name is MIPITX_VOLTAGE_SEL, so
I guess this control the voltage. If mipi_tx has the ability to control
the voltage, could we just treat mipi_tx as a regulator? For a
regulator, regulator-min-microvolt and regulator-max-microvolt would
limit the volt range and you could get it by
of_get_regulator_init_data(). If it actually control the current,
regulator-min-microamp and regulator-max-microamp could be used. I'm not
expert on this, so please give me more information on this.

[1]
http://lists.infradead.org/pipermail/linux-mediatek/2019-December/025638.html

Regards,
CK

>  Example:
>  
>  mipi_tx0: mipi-dphy@10215000 {
> @@ -42,6 +45,7 @@ mipi_tx0: mipi-dphy@10215000 {
>  	clock-output-names = "mipi_tx0_pll";
>  	#clock-cells = <0>;
>  	#phy-cells = <0>;
> +	mipitx-current-drive = <0x8>;
>  };
>  
>  dsi0: dsi@1401b000 {

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Re: [PATCH 4/4] drm/mediatek: config mipitx impedance with calibration data

[CK Hu]

Hi, Jitao:

On Mon, 2019-12-16 at 16:29 +0800, Jitao Shi wrote:
> Read calibration data from nvmem, and config mipitx impedance with
> calibration data to make sure their impedance are 100ohm.
> 
> Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
> ---
>  drivers/gpu/drm/mediatek/mtk_mipi_tx.h        |  1 +
>  drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c | 63 +++++++++++++++++++
>  2 files changed, 64 insertions(+)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_mipi_tx.h b/drivers/gpu/drm/mediatek/mtk_mipi_tx.h
> index eea44327fe9f..a1b6292145de 100644
> --- a/drivers/gpu/drm/mediatek/mtk_mipi_tx.h
> +++ b/drivers/gpu/drm/mediatek/mtk_mipi_tx.h
> @@ -28,6 +28,7 @@ struct mtk_mipi_tx {
>  	void __iomem *regs;
>  	u32 data_rate;
>  	u32 mipitx_drive;
> +	u32 rt_code[5];
>  	const struct mtk_mipitx_data *driver_data;
>  	struct clk_hw pll_hw;
>  	struct clk *pll;
> diff --git a/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c b/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c
> index 124fdf95f1e5..f624516944bb 100644
> --- a/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c
> +++ b/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c
> @@ -5,6 +5,8 @@
>   */
>  
>  #include "mtk_mipi_tx.h"
> +#include <linux/nvmem-consumer.h>
> +#include <linux/slab.h>
>  
>  #define MIPITX_LANE_CON		0x000c
>  #define RG_DSI_CPHY_T1DRV_EN		BIT(0)
> @@ -28,6 +30,7 @@
>  #define MIPITX_PLL_CON4		0x003c
>  #define RG_DSI_PLL_IBIAS		(3 << 10)
>  
> +#define MIPITX_D2P_RTCODE	0x0100
>  #define MIPITX_D2_SW_CTL_EN	0x0144
>  #define MIPITX_D0_SW_CTL_EN	0x0244
>  #define MIPITX_CK_CKMODE_EN	0x0328
> @@ -108,6 +111,64 @@ static const struct clk_ops mtk_mipi_tx_pll_ops = {
>  	.recalc_rate = mtk_mipi_tx_pll_recalc_rate,
>  };
>  
> +static int mtk_mipi_tx_config_calibration_data(struct mtk_mipi_tx *mipi_tx)
> +{
> +	u32 *buf = NULL;

Need not to assign NULL to buf, it would be assigned some value later.

> +	int i, j;
> +	struct nvmem_cell *cell;
> +	struct device *dev = mipi_tx->dev;
> +	size_t len;
> +
> +	cell = nvmem_cell_get(dev, "calibration-data");
> +	if (IS_ERR(cell)) {
> +		dev_warn(dev, "nvmem_cell_get fail\n");

In [1], nvmem is optional property, so I think you should use dev_dbg()
or dev_info().

[1]
http://lists.infradead.org/pipermail/linux-mediatek/2019-December/025640.html

> +		return -EINVAL;

The caller does not process return value, so I think you don't need to
return value.

> +	}
> +
> +	buf = (u32 *)nvmem_cell_read(cell, &len);
> +
> +	nvmem_cell_put(cell);
> +
> +	if (IS_ERR(buf)) {
> +		dev_warn(dev, "can't get data\n");
> +		return -EINVAL;
> +	}
> +
> +	if (len < 3 * sizeof(u32)) {
> +		dev_warn(dev, "invalid calibration data\n");
> +		kfree(buf);
> +		return -EINVAL;
> +	}
> +
> +	mipi_tx->rt_code[0] = ((buf[0] >> 6 & 0x1F) << 5) |

You don't access rt_code[] out of this function, so I think this could
be local variable.

> +			      (buf[0] >> 11 & 0x1F);

Lower case 0x1f.

> +	mipi_tx->rt_code[1] = ((buf[1] >> 27 & 0x1F) << 5) |
> +			      (buf[0] >> 1 & 0x1F);
> +	mipi_tx->rt_code[2] = ((buf[1] >> 17 & 0x1F) << 5) |
> +			      (buf[1] >> 22 & 0x1F);
> +	mipi_tx->rt_code[3] = ((buf[1] >> 7 & 0x1F) << 5) |
> +			      (buf[1] >> 12 & 0x1F);
> +	mipi_tx->rt_code[4] = ((buf[2] >> 27 & 0x1F) << 5) |
> +			      (buf[1] >> 2 & 0x1F);

Why not just save rt_code in nvmem and you don't need to translate here?
If you need to do so, please add description for this.

> +
> +	for (i = 0; i < 5; i++) {
> +		if ((mipi_tx->rt_code[i] & 0x1F) == 0)
> +			mipi_tx->rt_code[i] |= 0x10;
> +
> +		if ((mipi_tx->rt_code[i] >> 5 & 0x1F) == 0)
> +			mipi_tx->rt_code[i] |= 0x10 << 5;
> +
> +		for (j = 0; j < 10; j++) {
> +			mtk_mipi_tx_update_bits(mipi_tx,
> +				MIPITX_D2P_RTCODE * (i + 1) + j * 4,
> +				1, mipi_tx->rt_code[i] >> j & 1);
> +		}

There is only one statement in for-loop, so you could get rid of {}.

Regards,
CK

> +	}
> +
> +	kfree(buf);
> +	return 0;
> +}
> +
>  static void mtk_mipi_tx_power_on_signal(struct phy *phy)
>  {
>  	struct mtk_mipi_tx *mipi_tx = phy_get_drvdata(phy);
> @@ -130,6 +191,8 @@ static void mtk_mipi_tx_power_on_signal(struct phy *phy)
>  				RG_DSI_HSTX_LDO_REF_SEL,
>  				mipi_tx->mipitx_drive << 6);
>  
> +	mtk_mipi_tx_config_calibration_data(mipi_tx);
> +
>  	mtk_mipi_tx_set_bits(mipi_tx, MIPITX_CK_CKMODE_EN, DSI_CK_CKMODE_EN);
>  }
>  

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Re: [PATCH 1/4] dt-binds: display: mediatek: add property to control mipi tx drive current

[Jitao Shi]

On Wed, 2019-12-18 at 13:41 +0800, CK Hu wrote:
> Hi, Jitao:
> 
> On Mon, 2019-12-16 at 16:29 +0800, Jitao Shi wrote:
> > Add a property to control mipi tx drive current:
> > "mipitx-current-drive"
> > 
> > Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
> > ---
> >  .../devicetree/bindings/display/mediatek/mediatek,dsi.txt     | 4 ++++
> >  1 file changed, 4 insertions(+)
> > 
> > diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.txt b/Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.txt
> > index a19a6cc375ed..780201ddcd5c 100644
> > --- a/Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.txt
> > +++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.txt
> > @@ -33,6 +33,9 @@ Required properties:
> >  - #clock-cells: must be <0>;
> >  - #phy-cells: must be <0>.
> >  
> > +Optional properties:
> > +- mipitx-current-drive: adjust driving current, should be 1 ~ 0xF
> > +
> 
> In "[PATCH 3/4] drm/mediatek: add the mipitx driving control" [1], I see
> that you actually control a register its name is MIPITX_VOLTAGE_SEL, so
> I guess this control the voltage. If mipi_tx has the ability to control
> the voltage, could we just treat mipi_tx as a regulator? For a
> regulator, regulator-min-microvolt and regulator-max-microvolt would
> limit the volt range and you could get it by
> of_get_regulator_init_data(). If it actually control the current,
> regulator-min-microamp and regulator-max-microamp could be used. I'm not
> expert on this, so please give me more information on this.
> 
> [1]
> http://lists.infradead.org/pipermail/linux-mediatek/2019-December/025638.html
> 
> Regards,
> CK
> 

'MIPITX_VOLTAGE_SEL' is the whole 32bit name.
mipitx-current-drive is just bit[9:6] RG_DSI_HSTX_LDO_REF_SEL,

Not for voltage.

Best Regards
Jitao

> >  Example:
> >  
> >  mipi_tx0: mipi-dphy@10215000 {
> > @@ -42,6 +45,7 @@ mipi_tx0: mipi-dphy@10215000 {
> >  	clock-output-names = "mipi_tx0_pll";
> >  	#clock-cells = <0>;
> >  	#phy-cells = <0>;
> > +	mipitx-current-drive = <0x8>;
> >  };
> >  
> >  dsi0: dsi@1401b000 {
> 
> 

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