[PATCH v1 0/2] external ulpi vbus control

[PATCH v1 0/2] external ulpi vbus control

[Conor Dooley]

A customer sent me a patch adding a dt property to enable external vbus
control as their phy didn't support it*. I was surprised to see that none
of the other musb drivers made any use of this, but there is handling
in the musb core for it - made me feel like I was missing something as
to why it was not used by other drivers.

I've vendor prefixed the property for now, but I figure there may well
be a bunch of other potential users since this isn't just an musb thing,
given that there's a snps,ulpi-ext-vbus-drv used by an xHCI IP.

This is my third attempt to send these patches. I cannot find them on
lore from either of my previous attempts, so I'm gonna treat this as
v1. I think must've tried to send it from my kernel.org account from
Microchip's corp network and that failed. Either way, apologies if this
is #3 you've got from me..

* they didn't want to be identified, but said it was okay to post.

CC: Conor Dooley <conor.dooley@microchip.com>
CC: Daire McNamara <daire.mcnamara@microchip.com>
CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CC: Rob Herring <robh@kernel.org>
CC: Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>
CC: Bin Liu <b-liu@ti.com>
CC: linux-riscv@lists.infradead.org
CC: linux-usb@vger.kernel.org
CC: devicetree@vger.kernel.org
CC: linux-kernel@vger.kernel.org

Conor Dooley (2):
  dt-bindings: musb: mpfs: add ULPI external vbus support
  usb: musb: mpfs: detect UPLI external vbus control requirement from DT

 .../devicetree/bindings/usb/microchip,mpfs-musb.yaml       | 7 +++++++
 drivers/usb/musb/mpfs.c                                    | 2 ++
 2 files changed, 9 insertions(+)

-- 
2.43.2

[PATCH v1 1/2] dt-bindings: musb: mpfs: add ULPI external vbus support

[Conor Dooley]

Add a property to allow configuring the musb controller on PolarFire SoC
to use an external vbus for ULPI PHYs.

Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
---
 .../devicetree/bindings/usb/microchip,mpfs-musb.yaml       | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/Documentation/devicetree/bindings/usb/microchip,mpfs-musb.yaml b/Documentation/devicetree/bindings/usb/microchip,mpfs-musb.yaml
index c5e9ce2e7bc2a..27b909de49922 100644
--- a/Documentation/devicetree/bindings/usb/microchip,mpfs-musb.yaml
+++ b/Documentation/devicetree/bindings/usb/microchip,mpfs-musb.yaml
@@ -34,6 +34,13 @@ properties:
   clocks:
     maxItems: 1
 
+  microchip,ext-vbus-drv:
+    description:
+      Some ULPI USB PHYs do not support an internal VBUS supply and driving
+      the CPEN pin requires the configuration of the UPLI_USE__EXTVBUS
+      bit in ULPI_BUSCONTROL.
+    $ref: /schemas/types.yaml#/definitions/flag
+
 required:
   - compatible
   - reg
-- 
2.43.2

Re: [PATCH v1 1/2] dt-bindings: musb: mpfs: add ULPI external vbus support

[Krzysztof Kozlowski]

On 31/05/2024 09:04, Conor Dooley wrote:
> Add a property to allow configuring the musb controller on PolarFire SoC
> to use an external vbus for ULPI PHYs.
> 
> Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
> ---

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

Best regards,
Krzysztof

[PATCH v1 2/2] usb: musb: mpfs: detect UPLI external vbus control requirement from DT

[Conor Dooley]

The musb driver core already supports external vbus control for ULPI
PHYs, but none of the drivers actually enable it. A customer reported
needing this for their device, and now that a DT property for detecting
this configuration exists, read the property to enable the feature.

Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
---
 drivers/usb/musb/mpfs.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/usb/musb/mpfs.c b/drivers/usb/musb/mpfs.c
index f0f56df388355..29c7e5cdb230e 100644
--- a/drivers/usb/musb/mpfs.c
+++ b/drivers/usb/musb/mpfs.c
@@ -190,6 +190,8 @@ static int mpfs_probe(struct platform_device *pdev)
 	pdata->config = &mpfs_musb_hdrc_config;
 	pdata->platform_ops = &mpfs_ops;
 
+	pdata->extvbus = device_property_read_bool(dev, "microchip,ext-vbus-drv");
+
 	pdata->mode = usb_get_dr_mode(dev);
 	if (pdata->mode == USB_DR_MODE_UNKNOWN) {
 		dev_info(dev, "No dr_mode property found, defaulting to otg\n");
-- 
2.43.2