[PATCH v1] dt-bindings: usb: Fix EIC7700 USB reset's issue

[PATCH v1] dt-bindings: usb: Fix EIC7700 USB reset's issue

[caohang]

From: Hang Cao <caohang@eswincomputing.com>

The EIC7700 USB controller requires a USB PHY RESET operation.PHY RESET
operation was missed in the verification version, as it was performed in
ESWIN's U-Boot.

If a non-ESWIN provided loader is used, this issue will occur, resulting
in USB not work.This patch does not introduce any backward incompatibility
since the dts is not upstream yet.

Fixes: c640a4239db5 ("dt-bindings: usb: Add ESWIN EIC7700 USB controller")
Signed-off-by: Hang Cao <caohang@eswincomputing.com>
---
 .../devicetree/bindings/usb/eswin,eic7700-usb.yaml         | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/usb/eswin,eic7700-usb.yaml b/Documentation/devicetree/bindings/usb/eswin,eic7700-usb.yaml
index 41c3b1b98991..658260619423 100644
--- a/Documentation/devicetree/bindings/usb/eswin,eic7700-usb.yaml
+++ b/Documentation/devicetree/bindings/usb/eswin,eic7700-usb.yaml
@@ -41,12 +41,13 @@ properties:
       - const: usb_en

   resets:
-    maxItems: 2
+    maxItems: 3

   reset-names:
     items:
       - const: vaux
       - const: usb_rst
+      - const: usb_phy

   eswin,hsp-sp-csr:
     description:
@@ -85,8 +86,8 @@ examples:
         interrupt-parent = <&plic>;
         interrupts = <85>;
         interrupt-names = "peripheral";
-        resets = <&reset 84>, <&hspcrg 2>;
-        reset-names = "vaux", "usb_rst";
+        resets = <&reset 84>, <&hspcrg 2>, <&hspcrg 4>;
+        reset-names = "vaux", "usb_rst", "usb_phy";
         dr_mode = "peripheral";
         maximum-speed = "high-speed";
         phy_type = "utmi";
--
2.34.1

Re: [PATCH v1] dt-bindings: usb: Fix EIC7700 USB reset's issue

[Krzysztof Kozlowski]

On Tue, Apr 07, 2026 at 02:17:02PM +0800, caohang@eswincomputing.com wrote:
> From: Hang Cao <caohang@eswincomputing.com>
> 
> The EIC7700 USB controller requires a USB PHY RESET operation.PHY RESET

Missing space after full stop.

> operation was missed in the verification version, as it was performed in
> ESWIN's U-Boot.
> 
> If a non-ESWIN provided loader is used, this issue will occur, resulting
> in USB not work.This patch does not introduce any backward incompatibility
> since the dts is not upstream yet.

So U-Boot will be affected, no?

And even if DTS is not upstreamed, what about all out of tree DTS?
This is an already released ABI, so at least explain that driver does
not care about resets here and grabs them all.

> 
> Fixes: c640a4239db5 ("dt-bindings: usb: Add ESWIN EIC7700 USB controller")


Best regards,
Krzysztof

Re: [PATCH v1] dt-bindings: usb: Fix EIC7700 USB reset's issue

[Conor Dooley]

[-- Attachment #1: Type: text/plain, Size: 1267 bytes --]

On Wed, Apr 08, 2026 at 09:48:43AM +0200, Krzysztof Kozlowski wrote:
> On Tue, Apr 07, 2026 at 02:17:02PM +0800, caohang@eswincomputing.com wrote:
> > From: Hang Cao <caohang@eswincomputing.com>
> > 
> > The EIC7700 USB controller requires a USB PHY RESET operation.PHY RESET
> 
> Missing space after full stop.
> 
> > operation was missed in the verification version, as it was performed in
> > ESWIN's U-Boot.
> > 
> > If a non-ESWIN provided loader is used, this issue will occur, resulting
> > in USB not work.This patch does not introduce any backward incompatibility
> > since the dts is not upstream yet.
> 
> So U-Boot will be affected, no?

Is it even really affected? I don't think there's any bootloader for this
other than what ESWIN is shipping downstream, outside of people's development
trees. And any software that expected two resets will work just as badly as
it always did when a third one is added.

> And even if DTS is not upstreamed, what about all out of tree DTS?
> This is an already released ABI, so at least explain that driver does
> not care about resets here and grabs them all.
> 
> > 
> > Fixes: c640a4239db5 ("dt-bindings: usb: Add ESWIN EIC7700 USB controller")
> 
> 
> Best regards,
> Krzysztof
> 

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]

Re: Re: [PATCH v1] dt-bindings: usb: Fix EIC7700 USB reset's issue

[Hang Cao]

[-- Attachment #1: Type: text/plain, Size: 2702 bytes --]

Hi, Krzysztof & Conor

No, U-Boot will NOT be affected. Sorry for the misunderstanding due to the
inaccurate commit message.
 
I will send the next version with the improved commit message below:

The EIC7700 USB requires a USB PHY reset operation; otherwise, the USB will
not work. The reason why the USB driver that was applied can work properly is
that the USB PHY has already been reset in ESWIN's U-Boot.

However, the proper functioning of the USB driver should not be dependent on
the bootloader. Therefore, it is necessary to incorporate the USB PHY reset
signal into the DT bindings.

This patch does not introduce any backward incompatibility since the dts is
not upstream yet.  As array of reset operations are used in the driver,
no modifications to the USB controller driver are needed.


Best regards,
Hang

> -----Original Messages-----
> From: "Conor Dooley" <conor@kernel.org>
> Send time:Thursday, 09/04/2026 01:24:34
> To: "Krzysztof Kozlowski" <krzk@kernel.org>
> Cc: caohang@eswincomputing.com, gregkh@linuxfoundation.org, robh@kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org, Thinh.Nguyen@synopsys.com, p.zabel@pengutronix.de, linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, devicetree@vger.kernel.org, ningyu@eswincomputing.com, linmin@eswincomputing.com, pinkesh.vaghela@einfochips.com
> Subject: Re: [PATCH v1] dt-bindings: usb: Fix EIC7700 USB reset's issue
> 
> On Wed, Apr 08, 2026 at 09:48:43AM +0200, Krzysztof Kozlowski wrote:
> > On Tue, Apr 07, 2026 at 02:17:02PM +0800, caohang@eswincomputing.com wrote:
> > > From: Hang Cao <caohang@eswincomputing.com>
> > > 
> > > The EIC7700 USB controller requires a USB PHY RESET operation.PHY RESET
> > 
> > Missing space after full stop.
> > 
> > > operation was missed in the verification version, as it was performed in
> > > ESWIN's U-Boot.
> > > 
> > > If a non-ESWIN provided loader is used, this issue will occur, resulting
> > > in USB not work.This patch does not introduce any backward incompatibility
> > > since the dts is not upstream yet.
> > 
> > So U-Boot will be affected, no?
> 
> Is it even really affected? I don't think there's any bootloader for this
> other than what ESWIN is shipping downstream, outside of people's development
> trees. And any software that expected two resets will work just as badly as
> it always did when a third one is added.
> 
> > And even if DTS is not upstreamed, what about all out of tree DTS?
> > This is an already released ABI, so at least explain that driver does
> > not care about resets here and grabs them all.
> > 
> > > 
> > > Fixes: c640a4239db5 ("dt-bindings: usb: Add ESWIN EIC7700 USB controller")
> > 
> > 
> > Best regards,
> > Krzysztof
> > 

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 235 bytes --]