[PATCH v6 0/5] Modify interrupt handling for eUSB2 Phy targets

[PATCH v6 0/5] Modify interrupt handling for eUSB2 Phy targets

[Krishna Kurapati]

eUSB2 targets handle wakeup interrupts differently depending on device
speed when operating in host mode.

According to the eUSB2 specification, remote wakeup signaling in host
mode is detected via different data-line assertions based on the
connected device speed.

When a low-speed device is connected, the host repeater drives eD+ to
logic '1' upon detecting a K-state on the USB lines during remote wakeup
(eUSB2 specification, Section 5.5.14).

When a full-speed or high-speed device is connected, the host repeater
drives eD- to logic '1' upon detecting a K-state on the USB line during
remote wakeup (eUSB2 specification, Sections 5.5.15 and 5.5.18).

Since the eUSB2 PHY's "DP" and "DM" interrupt lines monitor the eD+ and
eD- line states, configure the wakeup interrupts accordingly

Add support for a new phy "type" attribute to be set by eusb2 phy drivers
and be read by consumers (in this case usb controller) and act accordingly

Changes in v6:
- Update commit messages to reflect why new EUSB2 phy type is added
- Update phy reading via index rather than by name
- Remove redundant header files in phy driver changes

Link to v5:
https://lore.kernel.org/all/20260723-eusb2-int-handling-v5-v5-0-f32ea6c1a318@oss.qualcomm.com/

Changes in v5:
- Add support for phy "type" attribute and set it from m31 and snps eusb2
phy probes.
- Removed adding a new binding property

Link to v4:
https://lore.kernel.org/all/20260709-eusb2-interrupt-handling-v5-v4-0-d4f993925608@oss.qualcomm.com/

Changes in v4:
- Moved to using binding approach as suggested by Thinh

Link to v3:
https://lore.kernel.org/all/20260511094422.3561509-1-krishna.kurapati@oss.qualcomm.com/

Changes in v3:
- Removed multiple glymur-dwc3-mp pdata entries
- Replaced use of ternary operators with if-else

Link to v2:
https://lore.kernel.org/all/20260505194242.1947891-1-krishna.kurapati@oss.qualcomm.com/

Changes in v2:
- Updated commit message
- added supported eUSB2 targets

Link to v1:
https://lore.kernel.org/all/20260502095616.666938-1-krishna.kurapati@oss.qualcomm.com/

Signed-off-by: Krishna Kurapati <krishna.kurapati@oss.qualcomm.com>
---
Krishna Kurapati (5):
      dt-bindings: phy: Add PHY_TYPE_EUSB2 definition
      include: linux: phy: Add phy attribute "type" and associated helpers
      phy: snps-eusb2: Set phy type to EUSB2
      phy: qcom: m31-eusb2: Set phy type to EUSB2
      usb: dwc3: qcom: Modify interrupt handling for eUSB2 Phy targets

 drivers/phy/phy-snps-eusb2.c              |  2 +
 drivers/phy/qualcomm/phy-qcom-m31-eusb2.c |  2 +
 drivers/usb/dwc3/dwc3-qcom.c              | 63 +++++++++++++++++++++++--------
 include/dt-bindings/phy/phy.h             |  1 +
 include/linux/phy/phy.h                   | 27 +++++++++++++
 5 files changed, 80 insertions(+), 15 deletions(-)
---
base-commit: ba8376e8c76c6512c98949dffbf4ded0b782a365
change-id: 20260825-eusb2-interrupt-v6-52bee4b24121

Best regards,
--  
Krishna Kurapati <krishna.kurapati@oss.qualcomm.com>


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[PATCH v6 1/5] dt-bindings: phy: Add PHY_TYPE_EUSB2 definition

[Krishna Kurapati]

eUSB2 (Embedded USB2) is a MIPI Alliance standard for chip-to-chip USB2
signaling. Unlike standard USB2, which uses 3.3V signaling, eUSB2 uses
low-voltage differential signaling (~0.4V) and requires a repeater to
interface with external USB2 ports. Because of these differences, eUSB2
PHY initialization sequences, voltage tuning, and register configuration
are distinct from USB2.

Additionally, eUSB2 targets handle wakeup interrupts differently
depending on device speed when operating in host mode. According to the
eUSB2 specification, remote wakeup signaling in host mode is detected
via different data-line assertions based on the connected device speed:

- Low-speed devices: the host repeater drives eD+ to logic '1' upon
  detecting a K-state on the USB lines during remote wakeup (eUSB2
  spec, Section 5.5.14).
- Full-speed/high-speed devices: the host repeater drives eD- to
  logic '1' upon detecting a K-state during remote wakeup (eUSB2 spec,
   Sections 5.5.15 and 5.5.18).

Since the eUSB2 PHY's DP and DM lines need to be configured differently
from USB2 PHYs, controllers should be able to query the PHY type and
configure wakeup interrupts accordingly.

Add PHY_TYPE_EUSB2 to distinguish eUSB2 PHYs from standard USB2 PHYs.

Signed-off-by: Krishna Kurapati <krishna.kurapati@oss.qualcomm.com>
---
 include/dt-bindings/phy/phy.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/include/dt-bindings/phy/phy.h b/include/dt-bindings/phy/phy.h
index 979b5dfd8353..555a022c8c0b 100644
--- a/include/dt-bindings/phy/phy.h
+++ b/include/dt-bindings/phy/phy.h
@@ -24,6 +24,7 @@
 #define PHY_TYPE_CPHY		11
 #define PHY_TYPE_USXGMII	12
 #define PHY_TYPE_XAUI		13
+#define PHY_TYPE_EUSB2		14
 
 #define PHY_POL_NORMAL		0
 #define PHY_POL_INVERT		1

-- 
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[PATCH v6 2/5] include: linux: phy: Add phy attribute "type" and associated helpers

[Krishna Kurapati]

In cases like USB High-speed phys which can be either USB2 or EUSB2, it is
required to know the type of phy (rather than the operating mode) because
DP and DM interrupt lines need to be configured differently for each of
them.

Add support to cache the PHY_TYPE and add the following helpers:

- phy_set_type() for the phy drivers (like m31_eusb2 or snps-eusb2) to
declare what type of PHY they are (in this case PHY_TYPE_EUSB2).

- phy_get_type() for the consumers (like USB controllers) to query the
type of phy connected to them.

Signed-off-by: Krishna Kurapati <krishna.kurapati@oss.qualcomm.com>
---
 include/linux/phy/phy.h | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/include/linux/phy/phy.h b/include/linux/phy/phy.h
index ea47975e288a..038c2b58bbe1 100644
--- a/include/linux/phy/phy.h
+++ b/include/linux/phy/phy.h
@@ -21,6 +21,8 @@
 #include <linux/phy/phy-lvds.h>
 #include <linux/phy/phy-mipi-dphy.h>
 
+#include <dt-bindings/phy/phy.h>
+
 struct phy;
 
 enum phy_mode {
@@ -152,11 +154,13 @@ struct phy_ops {
  * @bus_width: Data path width implemented by PHY
  * @max_link_rate: Maximum link rate supported by PHY (units to be decided by producer and consumer)
  * @mode: PHY mode
+ * @type: PHY type
  */
 struct phy_attrs {
 	u32			bus_width;
 	u32			max_link_rate;
 	enum phy_mode		mode;
+	int			type;
 };
 
 /**
@@ -262,6 +266,20 @@ static inline enum phy_mode phy_get_mode(struct phy *phy)
 {
 	return phy->attrs.mode;
 }
+
+static inline int phy_get_type(struct phy *phy)
+{
+	if (phy)
+		return phy->attrs.type;
+
+	return PHY_NONE;
+}
+
+static inline void phy_set_type(struct phy *phy, int type)
+{
+	phy->attrs.type = type;
+}
+
 int phy_reset(struct phy *phy);
 int phy_calibrate(struct phy *phy);
 int phy_notify_connect(struct phy *phy, int port);
@@ -393,6 +411,15 @@ static inline enum phy_mode phy_get_mode(struct phy *phy)
 	return PHY_MODE_INVALID;
 }
 
+static inline int phy_get_type(struct phy *phy)
+{
+	return PHY_NONE;
+}
+
+static inline void phy_set_type(struct phy *phy, int type)
+{
+}
+
 static inline int phy_reset(struct phy *phy)
 {
 	if (!phy)

-- 
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[PATCH v6 3/5] phy: snps-eusb2: Set phy type to EUSB2

[Krishna Kurapati]

USB controllers like DWC3 are agnostic of the kind of phy (USB2/eUSB2)
connected to it. Set the phy type to EUSB2 to let the controller know
the phy type when queried during its probe.

Signed-off-by: Krishna Kurapati <krishna.kurapati@oss.qualcomm.com>
---
 drivers/phy/phy-snps-eusb2.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/phy/phy-snps-eusb2.c b/drivers/phy/phy-snps-eusb2.c
index f90bf7e95463..fe4ce9d752f7 100644
--- a/drivers/phy/phy-snps-eusb2.c
+++ b/drivers/phy/phy-snps-eusb2.c
@@ -597,6 +597,8 @@ static int snps_eusb2_hsphy_probe(struct platform_device *pdev)
 		return PTR_ERR(generic_phy);
 	}
 
+	phy_set_type(generic_phy, PHY_TYPE_EUSB2);
+
 	dev_set_drvdata(dev, phy);
 	phy_set_drvdata(generic_phy, phy);
 

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[PATCH v6 4/5] phy: qcom: m31-eusb2: Set phy type to EUSB2

[Krishna Kurapati]

USB controllers like DWC3 are agnostic of the kind of phy (USB2/eUSB2)
connected to it. Set the phy type to EUSB2 to let the controller know
the phy type when queried during its probe.

Signed-off-by: Krishna Kurapati <krishna.kurapati@oss.qualcomm.com>
---
 drivers/phy/qualcomm/phy-qcom-m31-eusb2.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/phy/qualcomm/phy-qcom-m31-eusb2.c b/drivers/phy/qualcomm/phy-qcom-m31-eusb2.c
index 0bec8657149c..7e6b16b6952b 100644
--- a/drivers/phy/qualcomm/phy-qcom-m31-eusb2.c
+++ b/drivers/phy/qualcomm/phy-qcom-m31-eusb2.c
@@ -277,6 +277,8 @@ static int m31eusb2_phy_probe(struct platform_device *pdev)
 		return dev_err_probe(dev, PTR_ERR(phy->phy),
 				     "failed to create phy\n");
 
+	phy_set_type(phy->phy, PHY_TYPE_EUSB2);
+
 	ret = devm_regulator_bulk_get_const(dev, M31_EUSB_NUM_VREGS,
 					    m31_eusb_phy_vregs, &phy->vregs);
 	if (ret)

-- 
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[PATCH v6 5/5] usb: dwc3: qcom: Modify interrupt handling for eUSB2 Phy targets

[Krishna Kurapati]

eUSB2 targets handle wakeup interrupts differently depending on device
speed when operating in host mode.

According to the eUSB2 specification, remote wakeup signaling in host
mode is detected via different data-line assertions based on the
connected device speed.

When a low-speed device is connected, the host repeater drives eD+ to
logic '1' upon detecting a K-state on the USB lines during remote wakeup
(eUSB2 specification, Section 5.5.14).

When a full-speed or high-speed device is connected, the host repeater
drives eD- to logic '1' upon detecting a K-state on the USB line during
remote wakeup (eUSB2 specification, Sections 5.5.15 and 5.5.18).

Since the eUSB2 PHY's "DP" and "DM" interrupt lines monitor the eD+ and
eD- line states, query the phy type and configure the wakeup interrupts
accordingly.

Signed-off-by: Krishna Kurapati <krishna.kurapati@oss.qualcomm.com>
---
 drivers/usb/dwc3/dwc3-qcom.c | 63 +++++++++++++++++++++++++++++++++-----------
 1 file changed, 48 insertions(+), 15 deletions(-)

diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c
index f43f73ac36ff..9ba7ea31b524 100644
--- a/drivers/usb/dwc3/dwc3-qcom.c
+++ b/drivers/usb/dwc3/dwc3-qcom.c
@@ -85,6 +85,7 @@ struct dwc3_qcom {
 	struct icc_path		*icc_path_apps;
 
 	enum usb_role		current_role;
+	bool			has_eusb2_phy;
 };
 
 #define to_dwc3_qcom(d) container_of((d), struct dwc3_qcom, dwc)
@@ -272,15 +273,23 @@ static void dwc3_qcom_disable_wakeup_irq(int irq)
 	disable_irq_nosync(irq);
 }
 
-static void dwc3_qcom_disable_port_interrupts(struct dwc3_qcom_port *port)
+static void dwc3_qcom_disable_port_interrupts(struct dwc3_qcom *qcom, int port_index)
 {
+	struct dwc3_qcom_port *port = &qcom->ports[port_index];
+
 	dwc3_qcom_disable_wakeup_irq(port->qusb2_phy_irq);
 
 	if (port->usb2_speed == USB_SPEED_LOW) {
-		dwc3_qcom_disable_wakeup_irq(port->dm_hs_phy_irq);
+		if (qcom->has_eusb2_phy)
+			dwc3_qcom_disable_wakeup_irq(port->dp_hs_phy_irq);
+		else
+			dwc3_qcom_disable_wakeup_irq(port->dm_hs_phy_irq);
 	} else if ((port->usb2_speed == USB_SPEED_HIGH) ||
 			(port->usb2_speed == USB_SPEED_FULL)) {
-		dwc3_qcom_disable_wakeup_irq(port->dp_hs_phy_irq);
+		if (qcom->has_eusb2_phy)
+			dwc3_qcom_disable_wakeup_irq(port->dm_hs_phy_irq);
+		else
+			dwc3_qcom_disable_wakeup_irq(port->dp_hs_phy_irq);
 	} else {
 		dwc3_qcom_disable_wakeup_irq(port->dp_hs_phy_irq);
 		dwc3_qcom_disable_wakeup_irq(port->dm_hs_phy_irq);
@@ -289,26 +298,38 @@ static void dwc3_qcom_disable_port_interrupts(struct dwc3_qcom_port *port)
 	dwc3_qcom_disable_wakeup_irq(port->ss_phy_irq);
 }
 
-static void dwc3_qcom_enable_port_interrupts(struct dwc3_qcom_port *port)
+static void dwc3_qcom_enable_port_interrupts(struct dwc3_qcom *qcom, int port_index)
 {
+	struct dwc3_qcom_port *port = &qcom->ports[port_index];
+
 	dwc3_qcom_enable_wakeup_irq(port->qusb2_phy_irq, 0);
 
 	/*
 	 * Configure DP/DM line interrupts based on the USB2 device attached to
-	 * the root hub port. When HS/FS device is connected, configure the DP line
-	 * as falling edge to detect both disconnect and remote wakeup scenarios. When
-	 * LS device is connected, configure DM line as falling edge to detect both
-	 * disconnect and remote wakeup. When no device is connected, configure both
-	 * DP and DM lines as rising edge to detect HS/HS/LS device connect scenario.
+	 * the root hub port. For non-eUSB2 targets, when HS/FS device is connected,
+	 * configure the DP line as falling edge to detect disconnect and remote
+	 * wakeup. When LS device is connected, configure the DM line as falling edge
+	 * for the same. For eUSB2 targets, the lines are swapped and rising edge is
+	 * used: DP line for LS and DM line for HS/FS device detection. When no
+	 * device is connected, configure both DP and DM lines as rising edge to
+	 * detect HS/FS/LS device connect scenario.
 	 */
 
 	if (port->usb2_speed == USB_SPEED_LOW) {
-		dwc3_qcom_enable_wakeup_irq(port->dm_hs_phy_irq,
-					    IRQ_TYPE_EDGE_FALLING);
+		if (qcom->has_eusb2_phy)
+			dwc3_qcom_enable_wakeup_irq(port->dp_hs_phy_irq,
+						    IRQ_TYPE_EDGE_RISING);
+		else
+			dwc3_qcom_enable_wakeup_irq(port->dm_hs_phy_irq,
+						    IRQ_TYPE_EDGE_FALLING);
 	} else if ((port->usb2_speed == USB_SPEED_HIGH) ||
 			(port->usb2_speed == USB_SPEED_FULL)) {
-		dwc3_qcom_enable_wakeup_irq(port->dp_hs_phy_irq,
-					    IRQ_TYPE_EDGE_FALLING);
+		if (qcom->has_eusb2_phy)
+			dwc3_qcom_enable_wakeup_irq(port->dm_hs_phy_irq,
+						    IRQ_TYPE_EDGE_RISING);
+		else
+			dwc3_qcom_enable_wakeup_irq(port->dp_hs_phy_irq,
+						    IRQ_TYPE_EDGE_FALLING);
 	} else {
 		dwc3_qcom_enable_wakeup_irq(port->dp_hs_phy_irq,
 					    IRQ_TYPE_EDGE_RISING);
@@ -324,7 +345,7 @@ static void dwc3_qcom_disable_interrupts(struct dwc3_qcom *qcom)
 	int i;
 
 	for (i = 0; i < qcom->num_ports; i++)
-		dwc3_qcom_disable_port_interrupts(&qcom->ports[i]);
+		dwc3_qcom_disable_port_interrupts(qcom, i);
 }
 
 static void dwc3_qcom_enable_interrupts(struct dwc3_qcom *qcom)
@@ -332,7 +353,7 @@ static void dwc3_qcom_enable_interrupts(struct dwc3_qcom *qcom)
 	int i;
 
 	for (i = 0; i < qcom->num_ports; i++)
-		dwc3_qcom_enable_port_interrupts(&qcom->ports[i]);
+		dwc3_qcom_enable_port_interrupts(qcom, i);
 }
 
 static int dwc3_qcom_suspend(struct dwc3_qcom *qcom, bool wakeup)
@@ -617,6 +638,7 @@ static int dwc3_qcom_probe(struct platform_device *pdev)
 	int			ret;
 	bool			ignore_pipe_clk;
 	bool			wakeup_source;
+	struct phy		*phy;
 
 	qcom = devm_kzalloc(&pdev->dev, sizeof(*qcom), GFP_KERNEL);
 	if (!qcom)
@@ -683,6 +705,17 @@ static int dwc3_qcom_probe(struct platform_device *pdev)
 	if (ignore_pipe_clk)
 		dwc3_qcom_select_utmi_clk(qcom);
 
+	phy = devm_of_phy_get_by_index(dev, dev->of_node, 0);
+	if (IS_ERR(phy)) {
+		if (PTR_ERR(phy) != -ENODEV) {
+			ret = dev_err_probe(dev, PTR_ERR(phy),
+					    "failed to get usb2 phy\n");
+			goto clk_disable;
+		}
+		phy = NULL;
+	}
+	qcom->has_eusb2_phy = phy && (phy_get_type(phy) == PHY_TYPE_EUSB2);
+
 	qcom->mode = usb_get_dr_mode(dev);
 
 	if (qcom->mode == USB_DR_MODE_HOST) {

-- 
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Re: [PATCH v6 4/5] phy: qcom: m31-eusb2: Set phy type to EUSB2

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:

Pre-existing issues:
- [High] m31eusb2_phy_init fails to propagate error codes and always returns 0.
--

commit a59148cf39dc0afc1f852eb07be581b93aa157f1
Author: Krishna Kurapati <krishna.kurapati@oss.qualcomm.com>

phy: qcom: m31-eusb2: Set phy type to EUSB2

USB controllers like DWC3 are agnostic of the kind of phy (USB2/eUSB2)
connected to it. Set the phy type to EUSB2 to let the controller know
the phy type when queried during its probe.

> diff --git a/drivers/phy/qualcomm/phy-qcom-m31-eusb2.c b/drivers/phy/qualcomm/phy-qcom-m31-eusb2.c
> index 0bec8657149c9..7e6b16b6952b5 100644
> --- a/drivers/phy/qualcomm/phy-qcom-m31-eusb2.c
> +++ b/drivers/phy/qualcomm/phy-qcom-m31-eusb2.c

[ ... ]

[Severity: High]
This isn't a bug introduced by this patch, but m31eusb2_phy_init() fails to
propagate error codes and always returns 0.

If clk_prepare_enable() or phy_init(phy->repeater) fails, the code jumps
to the disable_repeater or disable_vreg labels:

drivers/phy/qualcomm/phy-qcom-m31-eusb2.c:m31eusb2_phy_init() {
    ...
disable_repeater:
	phy_exit(phy->repeater);
disable_vreg:
	regulator_bulk_disable(M31_EUSB_NUM_VREGS, phy->vregs);

	return 0;
}

Should this return the trapped error code ret instead of 0?

If a consumer driver like DWC3 receives a success status but the PHY
initialization actually failed, could it attempt to access an unpowered or
unclocked PHY?

Additionally, failure codes from hardware initialization functions like
m31eusb2_phy_write_sequence() are ignored:

drivers/phy/qualcomm/phy-qcom-m31-eusb2.c:m31eusb2_phy_init() {
    ...
	reset_control_deassert(phy->reset);

	m31eusb2_phy_write_sequence(phy, data->setup_seq, data->setup_seq_nregs);
    ...
}

Should the return value of m31eusb2_phy_write_sequence() be checked and
propagated as well?

-- 
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Re: [PATCH v6 5/5] usb: dwc3: qcom: Modify interrupt handling for eUSB2 Phy targets

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:

New issues:
- [Medium] The driver performs a fragile resource lookup for the USB2 PHY by hardcoding index 0 instead of resolving it by its defined name.

Pre-existing issues:
- [High] The legacy wrapper driver (`dwc3-qcom-legacy.c`) completely misses the new eUSB2 remote wakeup interrupt logic, breaking remote wakeup on upstream eUSB2 platforms utilizing the legacy binding.
--

commit fb96885fe62bdb840bbac9d8be2fe275a3e945ae
Author: Krishna Kurapati <krishna.kurapati@oss.qualcomm.com>

usb: dwc3: qcom: Modify interrupt handling for eUSB2 Phy targets

This commit modifies the dwc3 qcom driver to handle wakeup interrupts
differently for eUSB2 PHY targets based on connected device speed. It checks
for an eUSB2 PHY and configures DP/DM interrupt line states accordingly.

> diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c
> index f43f73ac36ff1..9ba7ea31b524f 100644
> --- a/drivers/usb/dwc3/dwc3-qcom.c
> +++ b/drivers/usb/dwc3/dwc3-qcom.c
[ ... ]
> -static void dwc3_qcom_enable_port_interrupts(struct dwc3_qcom_port *port)
> +static void dwc3_qcom_enable_port_interrupts(struct dwc3_qcom *qcom, int port_index)
>  {
> +	struct dwc3_qcom_port *port = &qcom->ports[port_index];
> +
>  	dwc3_qcom_enable_wakeup_irq(port->qusb2_phy_irq, 0);
>  
>  	/*
>  	 * Configure DP/DM line interrupts based on the USB2 device attached to
> -	 * the root hub port. When HS/FS device is connected, configure the DP line
> -	 * as falling edge to detect both disconnect and remote wakeup scenarios. When
> -	 * LS device is connected, configure DM line as falling edge to detect both
> -	 * disconnect and remote wakeup. When no device is connected, configure both
> -	 * DP and DM lines as rising edge to detect HS/HS/LS device connect scenario.
> +	 * the root hub port. For non-eUSB2 targets, when HS/FS device is connected,
> +	 * configure the DP line as falling edge to detect disconnect and remote
> +	 * wakeup. When LS device is connected, configure the DM line as falling edge
> +	 * for the same. For eUSB2 targets, the lines are swapped and rising edge is
> +	 * used: DP line for LS and DM line for HS/FS device detection. When no
> +	 * device is connected, configure both DP and DM lines as rising edge to
> +	 * detect HS/FS/LS device connect scenario.
>  	 */
>  
>  	if (port->usb2_speed == USB_SPEED_LOW) {
> -		dwc3_qcom_enable_wakeup_irq(port->dm_hs_phy_irq,
> -					    IRQ_TYPE_EDGE_FALLING);
> +		if (qcom->has_eusb2_phy)
> +			dwc3_qcom_enable_wakeup_irq(port->dp_hs_phy_irq,
> +						    IRQ_TYPE_EDGE_RISING);
> +		else
> +			dwc3_qcom_enable_wakeup_irq(port->dm_hs_phy_irq,
> +						    IRQ_TYPE_EDGE_FALLING);

[Severity: High]
This is a pre-existing issue, but does the legacy wrapper driver 
(drivers/usb/dwc3/dwc3-qcom-legacy.c) completely miss this new eUSB2 remote
wakeup interrupt logic?

The device tree for the Qualcomm SAR2130P SoC actively uses the legacy wrapper
binding (compatible = "qcom,sar2130p-dwc3", "qcom,dwc3") along with an eUSB2
PHY. When this SoC suspends the USB controller, dwc3_qcom_enable_port_interrupts
in the legacy driver configures the interrupt polarity incorrectly (as falling
edge instead of rising edge) because it lacks the eUSB2 checks introduced here.

Is an update required in the legacy wrapper so that upstream eUSB2 platforms
utilizing the legacy binding can correctly detect remote wakeup events?

[ ... ]
> @@ -683,6 +705,17 @@ static int dwc3_qcom_probe(struct platform_device *pdev)
>  	if (ignore_pipe_clk)
>  		dwc3_qcom_select_utmi_clk(qcom);
>  
> +	phy = devm_of_phy_get_by_index(dev, dev->of_node, 0);

[Severity: Medium]
Will this break if the USB3 PHY is placed first in the phys property array?

If index 0 retrieves the USB3 PHY instead, phy_get_type() will return
PHY_TYPE_USB3 rather than PHY_TYPE_EUSB2, falsely evaluating has_eusb2_phy
to false. The DT binding schema (snps,dwc3-common.yaml) does not enforce
the ordering of the phys array, but rather relies on the phy-names property
(enum: [usb2-phy, usb3-phy]).

Would it be more robust to use devm_phy_get(dev, "usb2-phy") to resolve the
PHY by its defined name instead of hardcoding index 0?

> +	if (IS_ERR(phy)) {
> +		if (PTR_ERR(phy) != -ENODEV) {
> +			ret = dev_err_probe(dev, PTR_ERR(phy),
> +					    "failed to get usb2 phy\n");
> +			goto clk_disable;
> +		}
> +		phy = NULL;
> +	}
> +	qcom->has_eusb2_phy = phy && (phy_get_type(phy) == PHY_TYPE_EUSB2);
> +
>  	qcom->mode = usb_get_dr_mode(dev);

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260826-eusb2-interrupt-v6-v6-0-ae2601cfa80c@oss.qualcomm.com?part=5

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