[PATCH 0/4] Add support for eUSB2 repeater on PMIV0104

[PATCH 0/4] Add support for eUSB2 repeater on PMIV0104

[Luca Weiss]

Add a new property qcom,tune-res-fsdif for the eUSB2 repeater and add
the compatible for the repeater on the PMIV0104 PMIC.

Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
---
Luca Weiss (4):
      dt-bindings: phy: qcom,snps-eusb2-repeater: Document qcom,tune-res-fsdif
      phy: qualcomm: phy-qcom-eusb2-repeater: Support tune-res-fsdif prop
      dt-bindings: phy: qcom,snps-eusb2-repeater: Add compatible for PMIV0104
      phy: qualcomm: phy-qcom-eusb2-repeater: Add support for PMIV0104

 .../devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml |  7 +++++++
 drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c            | 15 +++++++++++++++
 2 files changed, 22 insertions(+)
---
base-commit: d9946fe286439c2aeaa7953b8c316efe5b83d515
change-id: 20250620-sm7635-eusb-repeater-0d78f557290f
prerequisite-change-id: 20250616-eusb2-repeater-tuning-f56331c6b1fa:v2
prerequisite-patch-id: 5c504d171a4d1acd9ec376e01e0dd0fddbad92b8
prerequisite-patch-id: 0c97dcf5472fbed8ef4cffbd482f3169fe1e972d

Best regards,
-- 
Luca Weiss <luca.weiss@fairphone.com>

[PATCH 1/4] dt-bindings: phy: qcom,snps-eusb2-repeater: Document qcom,tune-res-fsdif

[Luca Weiss]

Document the FS Differential TX Output Resistance Tuning value found on
the eUSB2 repeater on Qualcomm PMICs.

Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
---
 Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml b/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
index 27f064a71c9fb8cb60e8333fb285f0510a4af94f..6bfd11657e2992735998063b3ca390e04a03930d 100644
--- a/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
+++ b/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
@@ -52,6 +52,12 @@ properties:
     minimum: 0
     maximum: 7
 
+  qcom,tune-res-fsdif:
+    $ref: /schemas/types.yaml#/definitions/uint8
+    description: FS Differential TX Output Resistance Tuning
+    minimum: 0
+    maximum: 7
+
 required:
   - compatible
   - reg

-- 
2.50.0

[PATCH 2/4] phy: qualcomm: phy-qcom-eusb2-repeater: Support tune-res-fsdif prop

[Luca Weiss]

Support reading the FS Differential TX Output Resistance Tuning from
devicetree and writing the register, as required on some boards.

Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
---
 drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c b/drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c
index d7493c2294ef23e37e484019a49ddf7b3d6a6a46..61594739e5b12706775622e1f76af6ad5d2d29bf 100644
--- a/drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c
+++ b/drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c
@@ -136,6 +136,9 @@ static int eusb2_repeater_init(struct phy *phy)
 	if (!of_property_read_u8(np, "qcom,tune-usb2-preem", &val))
 		regmap_write(regmap, base + EUSB2_TUNE_IUSB2, val);
 
+	if (!of_property_read_u8(np, "qcom,tune-res-fsdif", &val))
+		regmap_write(regmap, base + EUSB2_TUNE_RES_FSDIF, val);
+
 	/* Wait for status OK */
 	ret = regmap_read_poll_timeout(regmap, base + EUSB2_RPTR_STATUS, poll_val,
 				       poll_val & RPTR_OK, 10, 5);

-- 
2.50.0

[PATCH 3/4] dt-bindings: phy: qcom,snps-eusb2-repeater: Add compatible for PMIV0104

[Luca Weiss]

Add a dt-bindings compatible string for the Qualcomm's PMIV0104 PMIC.

Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
---
 Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml b/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
index 6bfd11657e2992735998063b3ca390e04a03930d..5bf0d6c9c0256300d00f84307b7f6ccf669f17c4 100644
--- a/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
+++ b/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
@@ -22,6 +22,7 @@ properties:
           - const: qcom,pm8550b-eusb2-repeater
       - enum:
           - qcom,pm8550b-eusb2-repeater
+          - qcom,pmiv0104-eusb2-repeater
           - qcom,smb2360-eusb2-repeater
 
   reg:

-- 
2.50.0

[PATCH 4/4] phy: qualcomm: phy-qcom-eusb2-repeater: Add support for PMIV0104

[Luca Weiss]

Add support for the eUSB2 repeater found on the PMIV0104. There is no
default init table for this PMIC, just the board-specific tuning
parameters are used on top of the default tuning values.

Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
---
 drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c b/drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c
index 61594739e5b12706775622e1f76af6ad5d2d29bf..3d4cdc4c18becd8efd5015e698b836ad4d7cf18c 100644
--- a/drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c
+++ b/drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c
@@ -82,6 +82,14 @@ static const struct eusb2_repeater_cfg pm8550b_eusb2_cfg = {
 	.num_vregs	= ARRAY_SIZE(pm8550b_vreg_l),
 };
 
+static const struct eusb2_repeater_cfg pmiv0104_eusb2_cfg = {
+	/* No PMIC-specific init sequence, only board level tuning via DT */
+	.init_tbl	= (struct eusb2_repeater_init_tbl_reg[]) {},
+	.init_tbl_num	= 0,
+	.vreg_list	= pm8550b_vreg_l,
+	.num_vregs	= ARRAY_SIZE(pm8550b_vreg_l),
+};
+
 static const struct eusb2_repeater_cfg smb2360_eusb2_cfg = {
 	.init_tbl	= smb2360_init_tbl,
 	.init_tbl_num	= ARRAY_SIZE(smb2360_init_tbl),
@@ -264,6 +272,10 @@ static const struct of_device_id eusb2_repeater_of_match_table[] = {
 		.compatible = "qcom,pm8550b-eusb2-repeater",
 		.data = &pm8550b_eusb2_cfg,
 	},
+	{
+		.compatible = "qcom,pmiv0104-eusb2-repeater",
+		.data = &pmiv0104_eusb2_cfg,
+	},
 	{
 		.compatible = "qcom,smb2360-eusb2-repeater",
 		.data = &smb2360_eusb2_cfg,

-- 
2.50.0

Re: [PATCH 2/4] phy: qualcomm: phy-qcom-eusb2-repeater: Support tune-res-fsdif prop

[neil.armstrong]

On 25/06/2025 11:14, Luca Weiss wrote:
> Support reading the FS Differential TX Output Resistance Tuning from
> devicetree and writing the register, as required on some boards.
> 
> Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
> ---
>   drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c | 3 +++
>   1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c b/drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c
> index d7493c2294ef23e37e484019a49ddf7b3d6a6a46..61594739e5b12706775622e1f76af6ad5d2d29bf 100644
> --- a/drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c
> +++ b/drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c
> @@ -136,6 +136,9 @@ static int eusb2_repeater_init(struct phy *phy)
>   	if (!of_property_read_u8(np, "qcom,tune-usb2-preem", &val))
>   		regmap_write(regmap, base + EUSB2_TUNE_IUSB2, val);
>   
> +	if (!of_property_read_u8(np, "qcom,tune-res-fsdif", &val))
> +		regmap_write(regmap, base + EUSB2_TUNE_RES_FSDIF, val);
> +
>   	/* Wait for status OK */
>   	ret = regmap_read_poll_timeout(regmap, base + EUSB2_RPTR_STATUS, poll_val,
>   				       poll_val & RPTR_OK, 10, 5);
> 

Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>

Re: [PATCH 4/4] phy: qualcomm: phy-qcom-eusb2-repeater: Add support for PMIV0104

[neil.armstrong]

On 25/06/2025 11:14, Luca Weiss wrote:
> Add support for the eUSB2 repeater found on the PMIV0104. There is no
> default init table for this PMIC, just the board-specific tuning
> parameters are used on top of the default tuning values.
> 
> Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
> ---
>   drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c | 12 ++++++++++++
>   1 file changed, 12 insertions(+)
> 
> diff --git a/drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c b/drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c
> index 61594739e5b12706775622e1f76af6ad5d2d29bf..3d4cdc4c18becd8efd5015e698b836ad4d7cf18c 100644
> --- a/drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c
> +++ b/drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c
> @@ -82,6 +82,14 @@ static const struct eusb2_repeater_cfg pm8550b_eusb2_cfg = {
>   	.num_vregs	= ARRAY_SIZE(pm8550b_vreg_l),
>   };
>   
> +static const struct eusb2_repeater_cfg pmiv0104_eusb2_cfg = {
> +	/* No PMIC-specific init sequence, only board level tuning via DT */
> +	.init_tbl	= (struct eusb2_repeater_init_tbl_reg[]) {},
> +	.init_tbl_num	= 0,
> +	.vreg_list	= pm8550b_vreg_l,
> +	.num_vregs	= ARRAY_SIZE(pm8550b_vreg_l),
> +};
> +
>   static const struct eusb2_repeater_cfg smb2360_eusb2_cfg = {
>   	.init_tbl	= smb2360_init_tbl,
>   	.init_tbl_num	= ARRAY_SIZE(smb2360_init_tbl),
> @@ -264,6 +272,10 @@ static const struct of_device_id eusb2_repeater_of_match_table[] = {
>   		.compatible = "qcom,pm8550b-eusb2-repeater",
>   		.data = &pm8550b_eusb2_cfg,
>   	},
> +	{
> +		.compatible = "qcom,pmiv0104-eusb2-repeater",
> +		.data = &pmiv0104_eusb2_cfg,
> +	},
>   	{
>   		.compatible = "qcom,smb2360-eusb2-repeater",
>   		.data = &smb2360_eusb2_cfg,
> 

Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>

Re: [PATCH 4/4] phy: qualcomm: phy-qcom-eusb2-repeater: Add support for PMIV0104

[Abel Vesa]

On 25-06-25 11:14:59, Luca Weiss wrote:
> Add support for the eUSB2 repeater found on the PMIV0104. There is no
> default init table for this PMIC, just the board-specific tuning
> parameters are used on top of the default tuning values.
> 
> Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>

Reviewed-by: Abel Vesa <abel.vesa@linaro.org>

Re: [PATCH 2/4] phy: qualcomm: phy-qcom-eusb2-repeater: Support tune-res-fsdif prop

[Abel Vesa]

On 25-06-25 11:14:57, Luca Weiss wrote:
> Support reading the FS Differential TX Output Resistance Tuning from
> devicetree and writing the register, as required on some boards.
> 
> Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>

Reviewed-by: Abel Vesa <abel.vesa@linaro.org>

Re: [PATCH 1/4] dt-bindings: phy: qcom,snps-eusb2-repeater: Document qcom,tune-res-fsdif

[Krzysztof Kozlowski]

On Wed, Jun 25, 2025 at 11:14:56AM +0200, Luca Weiss wrote:
> Document the FS Differential TX Output Resistance Tuning value found on
> the eUSB2 repeater on Qualcomm PMICs.
> 
> Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
> ---
>  Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml b/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
> index 27f064a71c9fb8cb60e8333fb285f0510a4af94f..6bfd11657e2992735998063b3ca390e04a03930d 100644
> --- a/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
> +++ b/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
> @@ -52,6 +52,12 @@ properties:
>      minimum: 0
>      maximum: 7
>  
> +  qcom,tune-res-fsdif:
> +    $ref: /schemas/types.yaml#/definitions/uint8
> +    description: FS Differential TX Output Resistance Tuning

Resistance is in Ohms, tuning could be in dB, so I wonder what are the
actual units here. Neither commit msg nor this description helps me to
understand that.

Best regards,
Krzysztof

Re: [PATCH 3/4] dt-bindings: phy: qcom,snps-eusb2-repeater: Add compatible for PMIV0104

[Krzysztof Kozlowski]

On Wed, Jun 25, 2025 at 11:14:58AM +0200, Luca Weiss wrote:
> Add a dt-bindings compatible string for the Qualcomm's PMIV0104 PMIC.
> 
> Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
> ---
>  Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml | 1 +

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Best regards,
Krzysztof

Re: [PATCH 1/4] dt-bindings: phy: qcom,snps-eusb2-repeater: Document qcom,tune-res-fsdif

[Krzysztof Kozlowski]

On Tue, Jul 08, 2025 at 10:13:24AM +0200, Krzysztof Kozlowski wrote:
> On Wed, Jun 25, 2025 at 11:14:56AM +0200, Luca Weiss wrote:
> > Document the FS Differential TX Output Resistance Tuning value found on
> > the eUSB2 repeater on Qualcomm PMICs.
> > 
> > Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
> > ---
> >  Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml | 6 ++++++
> >  1 file changed, 6 insertions(+)
> > 
> > diff --git a/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml b/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
> > index 27f064a71c9fb8cb60e8333fb285f0510a4af94f..6bfd11657e2992735998063b3ca390e04a03930d 100644
> > --- a/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
> > +++ b/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
> > @@ -52,6 +52,12 @@ properties:
> >      minimum: 0
> >      maximum: 7
> >  
> > +  qcom,tune-res-fsdif:
> > +    $ref: /schemas/types.yaml#/definitions/uint8
> > +    description: FS Differential TX Output Resistance Tuning
> 
> Resistance is in Ohms, tuning could be in dB, so I wonder what are the
> actual units here. Neither commit msg nor this description helps me to
> understand that.

I checked and the values are in Ohms.

Best regards,
Krzysztof

Re: [PATCH 1/4] dt-bindings: phy: qcom,snps-eusb2-repeater: Document qcom,tune-res-fsdif

[Luca Weiss]

On Tue Jul 8, 2025 at 10:21 AM CEST, Krzysztof Kozlowski wrote:
> On Tue, Jul 08, 2025 at 10:13:24AM +0200, Krzysztof Kozlowski wrote:
>> On Wed, Jun 25, 2025 at 11:14:56AM +0200, Luca Weiss wrote:
>> > Document the FS Differential TX Output Resistance Tuning value found on
>> > the eUSB2 repeater on Qualcomm PMICs.
>> > 
>> > Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
>> > ---
>> >  Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml | 6 ++++++
>> >  1 file changed, 6 insertions(+)
>> > 
>> > diff --git a/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml b/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
>> > index 27f064a71c9fb8cb60e8333fb285f0510a4af94f..6bfd11657e2992735998063b3ca390e04a03930d 100644
>> > --- a/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
>> > +++ b/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
>> > @@ -52,6 +52,12 @@ properties:
>> >      minimum: 0
>> >      maximum: 7
>> >  
>> > +  qcom,tune-res-fsdif:
>> > +    $ref: /schemas/types.yaml#/definitions/uint8
>> > +    description: FS Differential TX Output Resistance Tuning
>> 
>> Resistance is in Ohms, tuning could be in dB, so I wonder what are the
>> actual units here. Neither commit msg nor this description helps me to
>> understand that.
>
> I checked and the values are in Ohms.

Yes it's Ohms but not 0x00 = 0 ohms, and it's also an offset in ohms
from the nominal value according to the Hardware Register Description I
have, e.g. 0x7 = -12.1ohm from the default

I can try and create bindings using these Ohm offset values, I didn't
worry about it too much since the other tuning values in these bindings
are also just register values, presumably from before Konrad had access
to the docs.

Regards
Luca

>
> Best regards,
> Krzysztof

Re: [PATCH 1/4] dt-bindings: phy: qcom,snps-eusb2-repeater: Document qcom,tune-res-fsdif

[Luca Weiss]

Hi Krzysztof,

On Tue Jul 8, 2025 at 10:31 AM CEST, Luca Weiss wrote:
> On Tue Jul 8, 2025 at 10:21 AM CEST, Krzysztof Kozlowski wrote:
>> On Tue, Jul 08, 2025 at 10:13:24AM +0200, Krzysztof Kozlowski wrote:
>>> On Wed, Jun 25, 2025 at 11:14:56AM +0200, Luca Weiss wrote:
>>> > Document the FS Differential TX Output Resistance Tuning value found on
>>> > the eUSB2 repeater on Qualcomm PMICs.
>>> > 
>>> > Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
>>> > ---
>>> >  Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml | 6 ++++++
>>> >  1 file changed, 6 insertions(+)
>>> > 
>>> > diff --git a/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml b/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
>>> > index 27f064a71c9fb8cb60e8333fb285f0510a4af94f..6bfd11657e2992735998063b3ca390e04a03930d 100644
>>> > --- a/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
>>> > +++ b/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
>>> > @@ -52,6 +52,12 @@ properties:
>>> >      minimum: 0
>>> >      maximum: 7
>>> >  
>>> > +  qcom,tune-res-fsdif:
>>> > +    $ref: /schemas/types.yaml#/definitions/uint8
>>> > +    description: FS Differential TX Output Resistance Tuning
>>> 
>>> Resistance is in Ohms, tuning could be in dB, so I wonder what are the
>>> actual units here. Neither commit msg nor this description helps me to
>>> understand that.
>>
>> I checked and the values are in Ohms.
>
> Yes it's Ohms but not 0x00 = 0 ohms, and it's also an offset in ohms
> from the nominal value according to the Hardware Register Description I
> have, e.g. 0x7 = -12.1ohm from the default
>
> I can try and create bindings using these Ohm offset values, I didn't
> worry about it too much since the other tuning values in these bindings
> are also just register values, presumably from before Konrad had access
> to the docs.

I've taken some more looks, and checked how similar tuning is handled in
qcom,usb-snps-femto-v2.yaml and phy-qcom-snps-femto-v2.c, and changing up
the concept of tuning in the eUSB2-repeater bindings+driver is not a
trivial task.

Since this is adding just one more property in-line with the already
supported properties in the bindings+driver, can we get this in as-is,
and deprecate all 4 qcom,tune-* properties later with a replacement that
describes the values better?

We have enough people at Qualcomm by now that should be able to do that,
and have the required resources to answer any potential questions.

Regards
Luca

Re: [PATCH 1/4] dt-bindings: phy: qcom,snps-eusb2-repeater: Document qcom,tune-res-fsdif

[Krzysztof Kozlowski]

On 09/07/2025 11:40, Luca Weiss wrote:
> Hi Krzysztof,
> 
> On Tue Jul 8, 2025 at 10:31 AM CEST, Luca Weiss wrote:
>> On Tue Jul 8, 2025 at 10:21 AM CEST, Krzysztof Kozlowski wrote:
>>> On Tue, Jul 08, 2025 at 10:13:24AM +0200, Krzysztof Kozlowski wrote:
>>>> On Wed, Jun 25, 2025 at 11:14:56AM +0200, Luca Weiss wrote:
>>>>> Document the FS Differential TX Output Resistance Tuning value found on
>>>>> the eUSB2 repeater on Qualcomm PMICs.
>>>>>
>>>>> Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
>>>>> ---
>>>>>  Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml | 6 ++++++
>>>>>  1 file changed, 6 insertions(+)
>>>>>
>>>>> diff --git a/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml b/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
>>>>> index 27f064a71c9fb8cb60e8333fb285f0510a4af94f..6bfd11657e2992735998063b3ca390e04a03930d 100644
>>>>> --- a/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
>>>>> +++ b/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
>>>>> @@ -52,6 +52,12 @@ properties:
>>>>>      minimum: 0
>>>>>      maximum: 7
>>>>>  
>>>>> +  qcom,tune-res-fsdif:
>>>>> +    $ref: /schemas/types.yaml#/definitions/uint8
>>>>> +    description: FS Differential TX Output Resistance Tuning
>>>>
>>>> Resistance is in Ohms, tuning could be in dB, so I wonder what are the
>>>> actual units here. Neither commit msg nor this description helps me to
>>>> understand that.
>>>
>>> I checked and the values are in Ohms.
>>
>> Yes it's Ohms but not 0x00 = 0 ohms, and it's also an offset in ohms
>> from the nominal value according to the Hardware Register Description I
>> have, e.g. 0x7 = -12.1ohm from the default
>>
>> I can try and create bindings using these Ohm offset values, I didn't
>> worry about it too much since the other tuning values in these bindings
>> are also just register values, presumably from before Konrad had access
>> to the docs.
> 
> I've taken some more looks, and checked how similar tuning is handled in
> qcom,usb-snps-femto-v2.yaml and phy-qcom-snps-femto-v2.c, and changing up
> the concept of tuning in the eUSB2-repeater bindings+driver is not a
> trivial task.
> 
> Since this is adding just one more property in-line with the already
> supported properties in the bindings+driver, can we get this in as-is,
> and deprecate all 4 qcom,tune-* properties later with a replacement that
> describes the values better?

This is a new property, so other existing properties do not matter here.
We cannot take new code which you already think should be deprecated.

register-like values are acceptable for vendor properties, but that does
not make them usually more readable. The question is whether this should
be more readable for hardware engineers or anyone writing/validating
DTS. Is the actual resistance important or no one ever cares because you
paste whatever qcom told you and you do not know what should be actually
there?

I can imagine the first - that some document explains you should have
resistance of foo because of bar, which would mean the property should
be more readable. But I can also imagine the second. Make your claim in
commit msg.

> We have enough people at Qualcomm by now that should be able to do that,
> and have the required resources to answer any potential questions.
They are busy sending vendor/downstream tree patches...

Best regards,
Krzysztof

Re: [PATCH 1/4] dt-bindings: phy: qcom,snps-eusb2-repeater: Document qcom,tune-res-fsdif

[Luca Weiss]

On Wed Jul 9, 2025 at 12:16 PM CEST, Krzysztof Kozlowski wrote:
> On 09/07/2025 11:40, Luca Weiss wrote:
>> Hi Krzysztof,
>> 
>> On Tue Jul 8, 2025 at 10:31 AM CEST, Luca Weiss wrote:
>>> On Tue Jul 8, 2025 at 10:21 AM CEST, Krzysztof Kozlowski wrote:
>>>> On Tue, Jul 08, 2025 at 10:13:24AM +0200, Krzysztof Kozlowski wrote:
>>>>> On Wed, Jun 25, 2025 at 11:14:56AM +0200, Luca Weiss wrote:
>>>>>> Document the FS Differential TX Output Resistance Tuning value found on
>>>>>> the eUSB2 repeater on Qualcomm PMICs.
>>>>>>
>>>>>> Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
>>>>>> ---
>>>>>>  Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml | 6 ++++++
>>>>>>  1 file changed, 6 insertions(+)
>>>>>>
>>>>>> diff --git a/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml b/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
>>>>>> index 27f064a71c9fb8cb60e8333fb285f0510a4af94f..6bfd11657e2992735998063b3ca390e04a03930d 100644
>>>>>> --- a/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
>>>>>> +++ b/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
>>>>>> @@ -52,6 +52,12 @@ properties:
>>>>>>      minimum: 0
>>>>>>      maximum: 7
>>>>>>  
>>>>>> +  qcom,tune-res-fsdif:
>>>>>> +    $ref: /schemas/types.yaml#/definitions/uint8
>>>>>> +    description: FS Differential TX Output Resistance Tuning
>>>>>
>>>>> Resistance is in Ohms, tuning could be in dB, so I wonder what are the
>>>>> actual units here. Neither commit msg nor this description helps me to
>>>>> understand that.
>>>>
>>>> I checked and the values are in Ohms.
>>>
>>> Yes it's Ohms but not 0x00 = 0 ohms, and it's also an offset in ohms
>>> from the nominal value according to the Hardware Register Description I
>>> have, e.g. 0x7 = -12.1ohm from the default
>>>
>>> I can try and create bindings using these Ohm offset values, I didn't
>>> worry about it too much since the other tuning values in these bindings
>>> are also just register values, presumably from before Konrad had access
>>> to the docs.
>> 
>> I've taken some more looks, and checked how similar tuning is handled in
>> qcom,usb-snps-femto-v2.yaml and phy-qcom-snps-femto-v2.c, and changing up
>> the concept of tuning in the eUSB2-repeater bindings+driver is not a
>> trivial task.
>> 
>> Since this is adding just one more property in-line with the already
>> supported properties in the bindings+driver, can we get this in as-is,
>> and deprecate all 4 qcom,tune-* properties later with a replacement that
>> describes the values better?
>
> This is a new property, so other existing properties do not matter here.
> We cannot take new code which you already think should be deprecated.
>
> register-like values are acceptable for vendor properties, but that does
> not make them usually more readable. The question is whether this should
> be more readable for hardware engineers or anyone writing/validating
> DTS. Is the actual resistance important or no one ever cares because you
> paste whatever qcom told you and you do not know what should be actually
> there?
>
> I can imagine the first - that some document explains you should have
> resistance of foo because of bar, which would mean the property should
> be more readable. But I can also imagine the second. Make your claim in
> commit msg.

Would this text in the commit message work for you?

---
Document the FS Differential TX Output Resistance Tuning value found on
the eUSB2 repeater on Qualcomm PMICs. The tuning values have special
meanings, being different offsets of the resistance to the default value
in Ohms but the exact meaning is not relevant here, as the correct
tuning is determined by hardware engineers to make sure the electrical
properties are as expected.
---

I'm trying to avoid resending the whole series if we're not yet aligned
on the wording.

Regards
Luca

>
>> We have enough people at Qualcomm by now that should be able to do that,
>> and have the required resources to answer any potential questions.
> They are busy sending vendor/downstream tree patches...
>
> Best regards,
> Krzysztof

Re: [PATCH 1/4] dt-bindings: phy: qcom,snps-eusb2-repeater: Document qcom,tune-res-fsdif

[Krzysztof Kozlowski]

On 09/07/2025 14:22, Luca Weiss wrote:
> On Wed Jul 9, 2025 at 12:16 PM CEST, Krzysztof Kozlowski wrote:
>> On 09/07/2025 11:40, Luca Weiss wrote:
>>> Hi Krzysztof,
>>>
>>> On Tue Jul 8, 2025 at 10:31 AM CEST, Luca Weiss wrote:
>>>> On Tue Jul 8, 2025 at 10:21 AM CEST, Krzysztof Kozlowski wrote:
>>>>> On Tue, Jul 08, 2025 at 10:13:24AM +0200, Krzysztof Kozlowski wrote:
>>>>>> On Wed, Jun 25, 2025 at 11:14:56AM +0200, Luca Weiss wrote:
>>>>>>> Document the FS Differential TX Output Resistance Tuning value found on
>>>>>>> the eUSB2 repeater on Qualcomm PMICs.
>>>>>>>
>>>>>>> Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
>>>>>>> ---
>>>>>>>  Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml | 6 ++++++
>>>>>>>  1 file changed, 6 insertions(+)
>>>>>>>
>>>>>>> diff --git a/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml b/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
>>>>>>> index 27f064a71c9fb8cb60e8333fb285f0510a4af94f..6bfd11657e2992735998063b3ca390e04a03930d 100644
>>>>>>> --- a/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
>>>>>>> +++ b/Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml
>>>>>>> @@ -52,6 +52,12 @@ properties:
>>>>>>>      minimum: 0
>>>>>>>      maximum: 7
>>>>>>>  
>>>>>>> +  qcom,tune-res-fsdif:
>>>>>>> +    $ref: /schemas/types.yaml#/definitions/uint8
>>>>>>> +    description: FS Differential TX Output Resistance Tuning
>>>>>>
>>>>>> Resistance is in Ohms, tuning could be in dB, so I wonder what are the
>>>>>> actual units here. Neither commit msg nor this description helps me to
>>>>>> understand that.
>>>>>
>>>>> I checked and the values are in Ohms.
>>>>
>>>> Yes it's Ohms but not 0x00 = 0 ohms, and it's also an offset in ohms
>>>> from the nominal value according to the Hardware Register Description I
>>>> have, e.g. 0x7 = -12.1ohm from the default
>>>>
>>>> I can try and create bindings using these Ohm offset values, I didn't
>>>> worry about it too much since the other tuning values in these bindings
>>>> are also just register values, presumably from before Konrad had access
>>>> to the docs.
>>>
>>> I've taken some more looks, and checked how similar tuning is handled in
>>> qcom,usb-snps-femto-v2.yaml and phy-qcom-snps-femto-v2.c, and changing up
>>> the concept of tuning in the eUSB2-repeater bindings+driver is not a
>>> trivial task.
>>>
>>> Since this is adding just one more property in-line with the already
>>> supported properties in the bindings+driver, can we get this in as-is,
>>> and deprecate all 4 qcom,tune-* properties later with a replacement that
>>> describes the values better?
>>
>> This is a new property, so other existing properties do not matter here.
>> We cannot take new code which you already think should be deprecated.
>>
>> register-like values are acceptable for vendor properties, but that does
>> not make them usually more readable. The question is whether this should
>> be more readable for hardware engineers or anyone writing/validating
>> DTS. Is the actual resistance important or no one ever cares because you
>> paste whatever qcom told you and you do not know what should be actually
>> there?
>>
>> I can imagine the first - that some document explains you should have
>> resistance of foo because of bar, which would mean the property should
>> be more readable. But I can also imagine the second. Make your claim in
>> commit msg.
> 
> Would this text in the commit message work for you?
> 
> ---
> Document the FS Differential TX Output Resistance Tuning value found on
> the eUSB2 repeater on Qualcomm PMICs. The tuning values have special
> meanings, being different offsets of the resistance to the default value
> in Ohms but the exact meaning is not relevant here, as the correct
> tuning is determined by hardware engineers to make sure the electrical
> properties are as expected.
> ---
> 
> I'm trying to avoid resending the whole series if we're not yet aligned
> on the wording.
Sounds fine.

Best regards,
Krzysztof