Add QUSB2 PHY support for SC7180

Add compatibles for generic QUSB2 V2 phy which can be used for sdm845 and sc7180.

Signed-off-by Sandeep Maheswaram <[email protected]>

Reviewed-by Matthias Kaehlcke <[email protected]>

Reviewed-by Stephen Boyd <[email protected]>

---
 Documentation/devicetree/bindings/phy/qcom,qusb2-phy.yaml | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

In commit 8fe75cd4cddf ("phy: qcom-qusb2: Add generic QUSB2 V2 PHY support"), the change was made to add "qcom,qusb2-v2-phy" as a generic compat string. However the change also removed the "qcom,sdm845-qusb2-phy" compat string, which is documented in the binding and already in use.

This patch re-adds the "qcom,sdm845-qusb2-phy" compat string which allows the driver to continue to work with existing dts entries such as found on the db845c.

Cc Andy Gross <[email protected]>

Cc Bjorn Andersson <[email protected]>

Cc Rob Herring <[email protected]>

Cc Mark Rutland <[email protected]>

Cc Doug Anderson <[email protected]>

Cc Manu Gautam <[email protected]>

Cc Sandeep Maheswaram <[email protected]>

Cc Matthias Kaehlcke <[email protected]>

Cc Stephen Boyd <[email protected]>

Cc Kishon Vijay Abraham I <[email protected]>

Cc [email protected]

Cc [email protected]

Fixes 8fe75cd4cddf ("phy: qcom-qusb2: Add generic QUSB2 V2 PHY support")

Reported-by YongQin Liu <[email protected]>

Signed-off-by John Stultz <[email protected]>

---
 drivers/phy/qualcomm/phy-qcom-qusb2.c | 3 +++
 1 file changed, 3 insertions(+)

Hi,

Quoted 26 lines · John Stultz

In commit 8fe75cd4cddf ("phy: qcom-qusb2: Add generic QUSB2 V2 PHY support"), the change was made to add "qcom,qusb2-v2-phy" as a generic compat string. However the change also removed the "qcom,sdm845-qusb2-phy" compat string, which is documented in the binding and already in use.

This patch re-adds the "qcom,sdm845-qusb2-phy" compat string which allows the driver to continue to work with existing dts entries such as found on the db845c.

Cc Andy Gross <[email protected]>

Cc Bjorn Andersson <[email protected]>

Cc Rob Herring <[email protected]>

Cc Mark Rutland <[email protected]>

Cc Doug Anderson <[email protected]>

Cc Manu Gautam <[email protected]>

Cc Sandeep Maheswaram <[email protected]>

Cc Matthias Kaehlcke <[email protected]>

Cc Stephen Boyd <[email protected]>

Cc Kishon Vijay Abraham I <[email protected]>

Cc [email protected]

Cc [email protected]

Fixes 8fe75cd4cddf ("phy: qcom-qusb2: Add generic QUSB2 V2 PHY support")

Reported-by YongQin Liu <[email protected]>

Signed-off-by John Stultz <[email protected]>

Quoted 3 lines

---
 drivers/phy/qualcomm/phy-qcom-qusb2.c | 3 +++
 1 file changed, 3 insertions(+)

Do you have an out-of-tree dts file? If not, I'd prefer that the fix was for this patch to land instead:

https://lore.kernel.org/r/[email protected]

While we can land your patch if someone needs it for supporting an out-of-tree dts, it gives people supporting future SoCs the idea that they need to add themselves to this table too. That's now discouraged unless there's a specific quirk that needs to be handled just for this SoC.

Quoted 34 lines · Doug Anderson

Hi,

Quoted 26 lines · John Stultz

In commit 8fe75cd4cddf ("phy: qcom-qusb2: Add generic QUSB2 V2 PHY support"), the change was made to add "qcom,qusb2-v2-phy" as a generic compat string. However the change also removed the "qcom,sdm845-qusb2-phy" compat string, which is documented in the binding and already in use.

This patch re-adds the "qcom,sdm845-qusb2-phy" compat string which allows the driver to continue to work with existing dts entries such as found on the db845c.

Cc Andy Gross <[email protected]>

Cc Bjorn Andersson <[email protected]>

Cc Rob Herring <[email protected]>

Cc Mark Rutland <[email protected]>

Cc Doug Anderson <[email protected]>

Cc Manu Gautam <[email protected]>

Cc Sandeep Maheswaram <[email protected]>

Cc Matthias Kaehlcke <[email protected]>

Cc Stephen Boyd <[email protected]>

Cc Kishon Vijay Abraham I <[email protected]>

Cc [email protected]

Cc [email protected]

Fixes 8fe75cd4cddf ("phy: qcom-qusb2: Add generic QUSB2 V2 PHY support")

Reported-by YongQin Liu <[email protected]>

Signed-off-by John Stultz <[email protected]>

Quoted 3 lines

---
 drivers/phy/qualcomm/phy-qcom-qusb2.c | 3 +++
 1 file changed, 3 insertions(+)

Quoted 4 lines

Do you have an out-of-tree dts file? If not, I'd prefer that the fix was for this patch to land instead:

https://lore.kernel.org/r/[email protected]

No, no out of tree dts. The usage is already in tree:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/qcom/sdm845.dtsi#n2389

Quoted 5 lines

While we can land your patch if someone needs it for supporting an out-of-tree dts, it gives people supporting future SoCs the idea that they need to add themselves to this table too. That's now discouraged unless there's a specific quirk that needs to be handled just for this SoC.

My understanding with dts bindings is that they are effectively an ABI. While maybe it makes sense to deprecate the "qcom,sdm845-qusb2-phy" string in the Documentation to avoid new users, I'd think we'd want to keep the support in the driver as we aren't supposed to have tight coupling between the DTB and kernel (at least for official bindings).

Granted, I've not gotten much experience with boards that were fully upstream and thus didn't have an eternally evolving dts file that had to be kept in sync with the kernel, so in practice either solution does work for me, but in theory it seems like we should at least pretend these things are stable. :)

Quoted 6 lines · John Stultz

My understanding with dts bindings is that they are effectively an ABI. While maybe it makes sense to deprecate the "qcom,sdm845-qusb2-phy" string in the Documentation to avoid new users, I'd think we'd want to keep the support in the driver as we aren't supposed to have tight coupling between the DTB and kernel (at least for official bindings).

If nothing else if we're going to land your patch, can you at least put a comment in there that says "only needed to support legacy device trees that didn't include "qcom,qusb2-v2-phy" in the compatible string. Then the person who adds the next Qualcomm SoC will know not to add themselves to the table too.

Quoted 5 lines

Granted, I've not gotten much experience with boards that were fully upstream and thus didn't have an eternally evolving dts file that had to be kept in sync with the kernel, so in practice either solution does work for me, but in theory it seems like we should at least pretend these things are stable. :)

Yeah, I don't want to get into the whole stable ABI argument, but what you say is the official word. The bindings are supposed to be a stable ABI and it's a good goal to strive for.

...but in reality most people are OK with it not being quite so stable as long as it's not hurting anyone. What should have happened here is that the bindings and dts should have landed in one Linux version and the driver change landed in the next Linux version. Now we're stuck with the breakage, though. :( In general for "new" architectures it's considered more OK to break compatibility, though I guess you can argue whether sdm845 is really new enough. I guess to get at the meat of the issue though: if you need a patch to fix your problem anyway, why not land the patch that doesn't end up chewing extra up extra code space and providing a bad example for someone to copy?

Now certainly if changing your DTS was an undue burden (like you've already baked device trees into firmware) there's no question we should land your patch. I'm just not sure the lofty goal of "it's supposed to be a stable ABI so let's add an entry to the table that nobody will ever care about after the dts change lands" is enough of a reason to land it now.

Hi,

Quoted 26 lines · John Stultz

In commit 8fe75cd4cddf ("phy: qcom-qusb2: Add generic QUSB2 V2 PHY support"), the change was made to add "qcom,qusb2-v2-phy" as a generic compat string. However the change also removed the "qcom,sdm845-qusb2-phy" compat string, which is documented in the binding and already in use.

This patch re-adds the "qcom,sdm845-qusb2-phy" compat string which allows the driver to continue to work with existing dts entries such as found on the db845c.

Cc Andy Gross <[email protected]>

Cc Bjorn Andersson <[email protected]>

Cc Rob Herring <[email protected]>

Cc Mark Rutland <[email protected]>

Cc Doug Anderson <[email protected]>

Cc Manu Gautam <[email protected]>

Cc Sandeep Maheswaram <[email protected]>

Cc Matthias Kaehlcke <[email protected]>

Cc Stephen Boyd <[email protected]>

Cc Kishon Vijay Abraham I <[email protected]>

Cc [email protected]

Cc [email protected]

Fixes 8fe75cd4cddf ("phy: qcom-qusb2: Add generic QUSB2 V2 PHY support")

Reported-by YongQin Liu <[email protected]>

Signed-off-by John Stultz <[email protected]>

Quoted 3 lines

---
 drivers/phy/qualcomm/phy-qcom-qusb2.c | 3 +++
 1 file changed, 3 insertions(+)

Do you have an out-of-tree dts file? If not, I'd prefer that the fix was for this patch to land instead:

https://lore.kernel.org/r/[email protected]

While we can land your patch if someone needs it for supporting an out-of-tree dts, it gives people supporting future SoCs the idea that they need to add themselves to this table too. That's now discouraged unless there's a specific quirk that needs to be handled just for this SoC.

In commit 8fe75cd4cddf ("phy: qcom-qusb2: Add generic QUSB2 V2 PHY support"), the change was made to add "qcom,qusb2-v2-phy" as a generic compat string. However the change also removed the "qcom,sdm845-qusb2-phy" compat string, which is documented in the binding and already in use.

This patch re-adds the "qcom,sdm845-qusb2-phy" compat string which allows the driver to continue to work with existing dts entries such as found on the db845c.

Cc Andy Gross <[email protected]>

Cc Bjorn Andersson <[email protected]>

Cc Rob Herring <[email protected]>

Cc Mark Rutland <[email protected]>

Cc Doug Anderson <[email protected]>

Cc Manu Gautam <[email protected]>

Cc Sandeep Maheswaram <[email protected]>

Cc Matthias Kaehlcke <[email protected]>

Cc Stephen Boyd <[email protected]>

Cc Kishon Vijay Abraham I <[email protected]>

Cc [email protected]

Cc [email protected]

Fixes 8fe75cd4cddf ("phy: qcom-qusb2: Add generic QUSB2 V2 PHY support")

Reported-by YongQin Liu <[email protected]>

Signed-off-by John Stultz <[email protected]>

---
 drivers/phy/qualcomm/phy-qcom-qusb2.c | 3 +++
 1 file changed, 3 insertions(+)

drivers/phy/qualcomm/phy-qcom-qusb2.c +3 -0

index 3708d43b7508..ab7941ce5d3a 100644
@@ -815,6 +815,9 @@ static const struct of_device_id qusb2_phy_of_match_table[] = {
 	}, {
 		.compatible	= "qcom,msm8998-qusb2-phy",
 		.data		= &msm8998_phy_cfg,
+	}, {
+		.compatible	= "qcom,sdm845-qusb2-phy",
+		.data		= &qusb2_v2_phy_cfg,
 	}, {
 		.compatible	= "qcom,qusb2-v2-phy",
 		.data		= &qusb2_v2_phy_cfg,

Signature · 1 line

2.17.1

In commit 8fe75cd4cddf ("phy: qcom-qusb2: Add generic QUSB2 V2 PHY support"), the change was made to add "qcom,qusb2-v2-phy" as a generic compat string. However the change also removed the "qcom,sdm845-qusb2-phy" compat string, which is documented in the binding and already in use.

This patch re-adds the "qcom,sdm845-qusb2-phy" compat string which allows the driver to continue to work with existing dts entries such as found on the db845c.

Cc Andy Gross <[email protected]>

Cc Bjorn Andersson <[email protected]>

Cc Rob Herring <[email protected]>

Cc Mark Rutland <[email protected]>

Cc Doug Anderson <[email protected]>

Cc Manu Gautam <[email protected]>

Cc Sandeep Maheswaram <[email protected]>

Cc Matthias Kaehlcke <[email protected]>

Cc Stephen Boyd <[email protected]>

Cc Kishon Vijay Abraham I <[email protected]>

Cc [email protected]

Cc [email protected]

Reviewed-by Bjorn Andersson <[email protected]>

Fixes 8fe75cd4cddf ("phy: qcom-qusb2: Add generic QUSB2 V2 PHY support")

Reported-by YongQin Liu <[email protected]>

Signed-off-by John Stultz <[email protected]>

---
v2: Add deprecation note on "qcom,sdm845-qusb2-phy" string
as suggested by Doug.

---
 drivers/phy/qualcomm/phy-qcom-qusb2.c | 7 +++++++
 1 file changed, 7 insertions(+)

drivers/phy/qualcomm/phy-qcom-qusb2.c +0 -0

index 3708d43b7508..393011a05b48 100644

In commit 8fe75cd4cddf ("phy: qcom-qusb2: Add generic QUSB2 V2 PHY support"), the change was made to add "qcom,qusb2-v2-phy" as a generic compat string. However the change also removed the "qcom,sdm845-qusb2-phy" compat string, which is documented in the binding and already in use.

This patch re-adds the "qcom,sdm845-qusb2-phy" compat string which allows the driver to continue to work with existing dts entries such as found on the db845c.

Cc Andy Gross <[email protected]>

Cc Bjorn Andersson <[email protected]>

Cc Rob Herring <[email protected]>

Cc Mark Rutland <[email protected]>

Cc Doug Anderson <[email protected]>

Cc Manu Gautam <[email protected]>

Cc Sandeep Maheswaram <[email protected]>

Cc Matthias Kaehlcke <[email protected]>

Cc Stephen Boyd <[email protected]>

Cc Kishon Vijay Abraham I <[email protected]>

Cc [email protected]

Cc [email protected]

Reviewed-by Bjorn Andersson <[email protected]>

Fixes 8fe75cd4cddf ("phy: qcom-qusb2: Add generic QUSB2 V2 PHY support")

Reported-by YongQin Liu <[email protected]>

Signed-off-by John Stultz <[email protected]>

---

drivers/phy/qualcomm/phy-qcom-qusb2.c static const struct of_device_id qusb2_phy_of_match_table[] = { · line 781

Quoted 11 lines · Sandeep Maheswaram

drivers/phy/qualcomm/phy-qcom-qusb2.c +2 -2

@@ -774,8 +774,8 @@ static const struct of_device_id qusb2_phy_of_match_table[] = {
                .compatible     = "qcom,msm8998-qusb2-phy",
                .data           = &msm8998_phy_cfg,
        }, {
-               .compatible     = "qcom,sdm845-qusb2-phy",
-               .data           = &sdm845_phy_cfg,
+               .compatible     = "qcom,qusb2-v2-phy",
+               .data           = &qusb2_v2_phy_cfg,
        },
        { },
 };

Just as a heads up, Yongqin (cc'ed) reported this patch (now upstream) seems to be causing trouble on the db845c.

It seems like its removing support for the "qcom,sdm845-qusb2-phy" compatible string, which is documented:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/devicetree/bindings/phy/qcom,qusb2-phy.yaml#n23

and already in use:

   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/qcom/sdm845.dtsi#n2389

Should this instead have been an addition of the "qcom,qusb2-v2-phy", line instead of replacing "qcom,sdm845-qusb2-phy"?

Use generic QUSB2 V2 Phy configuration for sdm845.

Signed-off-by Sandeep Maheswaram <[email protected]>

Reviewed-by Matthias Kaehlcke <[email protected]>

Reviewed-by Stephen Boyd <[email protected]>

---
 arch/arm64/boot/dts/qcom/sdm845.dtsi | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Converting dt binding to yaml.
Adding compatible for SC7180 in dt bindings.
Added generic QUSB2 V2 PHY support and using the same SC7180 and SDM845.

Changes in v5:
*Added the dt bindings which are applicable only to QUSB2 V2 PHY in
separate block as per comments from Matthias in patch 1/9 and patch 4/9 and addressed Rob's comment in patch 1/9.
*Separated the patch for new override params and added a local variable
to access overrides as per comments from Matthias patch 5/9 and 6/9.

Changes in v4:
*Addressed Rob Herrings comments in dt bindings.
*Added new structure for all the overriding tuning params. *Removed the sc7180 and sdm845 compatible from driver and added qusb2 v2 phy. *Added the qusb2 v2 phy compatible in device tree for sc7180 and sdm845.

Changes in v3:
*Using the generic phy cfg table for QUSB2 V2 phy. *Added support for overriding tuning parameters in QUSB2 V2 PHY from device tree.

Changes in v2:
Sorted the compatible in driver.
Converted dt binding to yaml.
Added compatible in yaml.

Sandeep Maheswaram (9):
dt-bindings: phy: qcom,qusb2: Convert QUSB2 phy bindings to yaml
dt-bindings: phy: qcom,qusb2: Add compatibles for QUSB2 V2 phy and

    SC7180

phy: qcom-qusb2: Add generic QUSB2 V2 PHY support
dt-bindings: phy: qcom-qusb2: Add support for overriding Phy tuning
parameters
phy: qcom-qusb2: Add support for overriding tuning parameters in QUSB2
V2 PHY
phy: qcom-qusb2: Add new overriding tuning parameters in QUSB2 V2 PHY
arm64: dts: qcom: sc7180: Add generic QUSB2 V2 Phy compatible
arm64: dts: qcom: sdm845: Add generic QUSB2 V2 Phy compatible
arm64: dts: qcom: sc7180: Update QUSB2 V2 Phy params for SC7180 IDP
device

 .../devicetree/bindings/phy/qcom,qusb2-phy.yaml    | 187 +++++++++++++++++++++
 .../devicetree/bindings/phy/qcom-qusb2-phy.txt     |  68 --------
 arch/arm64/boot/dts/qcom/sc7180-idp.dts            |   6 +-
 arch/arm64/boot/dts/qcom/sc7180.dtsi               |   2 +-
 arch/arm64/boot/dts/qcom/sdm845.dtsi               |   4 +-
 drivers/phy/qualcomm/phy-qcom-qusb2.c              | 144 +++++++++++-----
 6 files changed, 297 insertions(+), 114 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/phy/qcom,qusb2-phy.yaml
 delete mode 100644 Documentation/devicetree/bindings/phy/qcom-qusb2-phy.txt

Signature · 2 lines

QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation

Converting dt binding to yaml.
Adding compatible for SC7180 in dt bindings.
Added generic QUSB2 V2 PHY support and using the same SC7180 and SDM845.

Changes in v5:
*Added the dt bindings which are applicable only to QUSB2 V2 PHY in
separate block as per comments from Matthias in patch 1/9 and patch 4/9 and addressed Rob's comment in patch 1/9.
*Separated the patch for new override params and added a local variable
to access overrides as per comments from Matthias patch 5/9 and 6/9.

Changes in v4:
*Addressed Rob Herrings comments in dt bindings.
*Added new structure for all the overriding tuning params. *Removed the sc7180 and sdm845 compatible from driver and added qusb2 v2 phy. *Added the qusb2 v2 phy compatible in device tree for sc7180 and sdm845.

Changes in v3:
*Using the generic phy cfg table for QUSB2 V2 phy. *Added support for overriding tuning parameters in QUSB2 V2 PHY from device tree.

Changes in v2:
Sorted the compatible in driver.
Converted dt binding to yaml.
Added compatible in yaml.

Sandeep Maheswaram (9):
dt-bindings: phy: qcom,qusb2: Convert QUSB2 phy bindings to yaml
dt-bindings: phy: qcom,qusb2: Add compatibles for QUSB2 V2 phy and

    SC7180

phy: qcom-qusb2: Add generic QUSB2 V2 PHY support
dt-bindings: phy: qcom-qusb2: Add support for overriding Phy tuning
parameters
phy: qcom-qusb2: Add support for overriding tuning parameters in QUSB2
V2 PHY
phy: qcom-qusb2: Add new overriding tuning parameters in QUSB2 V2 PHY

arm64: dts: qcom: sc7180: Add generic QUSB2 V2 Phy compatible
arm64: dts: qcom: sdm845: Add generic QUSB2 V2 Phy compatible
arm64: dts: qcom: sc7180: Update QUSB2 V2 Phy params for SC7180 IDP
device

 .../devicetree/bindings/phy/qcom,qusb2-phy.yaml    | 187 +++++++++++++++++++++
 .../devicetree/bindings/phy/qcom-qusb2-phy.txt     |  68 --------
 arch/arm64/boot/dts/qcom/sc7180-idp.dts            |   6 +-
 arch/arm64/boot/dts/qcom/sc7180.dtsi               |   2 +-
 arch/arm64/boot/dts/qcom/sdm845.dtsi               |   4 +-
 drivers/phy/qualcomm/phy-qcom-qusb2.c              | 144 +++++++++++-----
 6 files changed, 297 insertions(+), 114 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/phy/qcom,qusb2-phy.yaml
 delete mode 100644 Documentation/devicetree/bindings/phy/qcom-qusb2-phy.txt