[PATCH v12 0/6] USB DWC3 host wake up support from system suspend

[PATCH v12 0/6] USB DWC3 host wake up support from system suspend

[Sandeep Maheswaram]

Avoiding phy powerdown in host mode when wakeup capable devices are 
connected, so that it can be wake up by devices.
Set GENPD_FLAG_ALWAYS_ON flag to keep usb30_prim gdsc active to retain
controller status during suspend/resume.

Changes in v12:
Squashed PATCH 1/5 and 2/5 of v11.
Added dt bindings and device tree entry for wakeup-source property
for dwc3 core node.
Dropped redundant phy_set_mode call.


Changes in v11:
Moving back to v8 version
https://patchwork.kernel.org/project/linux-arm-msm/cover/1624882097-23265-1-git-send-email-sanm@codeaurora.org
as we are getting interrupts during suspend
when enabling both DP hs phy irq and DM hs phy irq.
Moved the set phy mode function to dwc3/core.c from xhci-plat.c
We didn't find any other option other than accessing xhci from dwc.

Changes in v10:
PATCH 1/6: Change device_set_wakeup_capable to device_set_wakeup_enable
PATCH 2/6: Remove redundant else part in dwc3_resume_common
PATCH 4/6: Change the irg flags
PATCH 5/6: Set flag GENPD_FLAG_ALWAYS_ON
PATCH 6/6: Remove disable interrupts function and enable
interrupts in probe.


Changes in v9:
Checking with device_may_makeup property instead of phy_power_off flag.
Changed the IRQ flags and removed hs_phy_mode variable.

Changes in v8:
Moved the dwc3 suspend quirk code in dwc3/host.c to xhci-plat.c
Checking phy_power_off flag instead of usb_wakeup_enabled_descendants 
to keep gdsc active.

Changes in v7:
Change in commit text and message in PATCH 1/5 and PATCH 5/5
as per Matthias suggestion.
Added curly braces for if and else if sections in PATCH 4/5.

Changes in v6:
Addressed comments in host.c and core.c
Separated the patches in dwc3-qcom.c to make it simple.
Dropped wakeup-source change as it is not related to this series.

Changes in v5:
Added phy_power_off flag to check presence of wakeup capable devices.
Dropped patch[v4,4/5] as it is present linux-next.
Addressed comments in host.c and dwc3-qcom.c.

Changes in v4:
Addressed Matthias comments raised in v3.

Changes in v3:
Removed need_phy_for_wakeup flag and by default avoiding phy powerdown.
Addressed Matthias comments and added entry for DEV_SUPERSPEED.
Added suspend_quirk in dwc3 host and moved the dwc3_set_phy_speed_flags.
Added wakeup-source dt entry and reading in dwc-qcom.c glue driver.

Changes in v2:
Dropped the patch in clock to set GENPD_FLAG_ACTIVE_WAKEUP flag and 
setting in usb dwc3 driver.
Separated the core patch and glue driver patch.
Made need_phy_for_wakeup flag part of dwc structure and 
hs_phy_flags as unsgined int.
Adrressed the comment on device_init_wakeup call.
Corrected offset for reading portsc register.
Added pacth to support wakeup in xo shutdown case.


Sandeep Maheswaram (6):
  usb: dwc3: core: Host wake up support from system suspend
  usb: dwc3: qcom: Add helper functions to enable,disable wake irqs
  usb: dwc3: qcom: Configure wakeup interrupts during suspend
  usb: dwc3: qcom: Keep power domain on to retain controller status
  dt-bindings: usb: dwc3: Add wakeup-source property support
  arm64: dts: qcom: sc7280: Add wakeup-source property for USB node

 .../devicetree/bindings/usb/snps,dwc3.yaml         |  5 ++
 arch/arm64/boot/dts/qcom/sc7280.dtsi               |  1 +
 drivers/usb/dwc3/core.c                            | 29 ++++++---
 drivers/usb/dwc3/core.h                            |  4 ++
 drivers/usb/dwc3/dwc3-qcom.c                       | 74 +++++++++++++---------
 drivers/usb/dwc3/host.c                            | 25 ++++++++
 6 files changed, 99 insertions(+), 39 deletions(-)

-- 
2.7.4

[PATCH v12 1/6] usb: dwc3: core: Host wake up support from system suspend

[Sandeep Maheswaram]

During suspend read the status of all port and set hs phy mode
based on current speed. Use this hs phy mode to configure wakeup
interrupts in qcom glue driver.

Also check during suspend if any wakeup capable devices are
connected to the controller (directly or through hubs), if there
are none set a flag to indicate that the PHY is powered
down during suspend.

Signed-off-by: Sandeep Maheswaram <quic_c_sanm@quicinc.com>
---
 drivers/usb/dwc3/core.c | 29 ++++++++++++++++++++---------
 drivers/usb/dwc3/core.h |  4 ++++
 drivers/usb/dwc3/host.c | 25 +++++++++++++++++++++++++
 3 files changed, 49 insertions(+), 9 deletions(-)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 1170b80..b102a22 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -32,6 +32,7 @@
 #include <linux/usb/gadget.h>
 #include <linux/usb/of.h>
 #include <linux/usb/otg.h>
+#include <linux/usb/hcd.h>
 
 #include "core.h"
 #include "gadget.h"
@@ -1723,6 +1724,7 @@ static int dwc3_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, dwc);
 	dwc3_cache_hwparams(dwc);
+	device_init_wakeup(&pdev->dev, of_property_read_bool(dev->of_node, "wakeup-source"));
 
 	spin_lock_init(&dwc->lock);
 	mutex_init(&dwc->mutex);
@@ -1865,6 +1867,7 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
 {
 	unsigned long	flags;
 	u32 reg;
+	struct usb_hcd  *hcd = platform_get_drvdata(dwc->xhci);
 
 	switch (dwc->current_dr_role) {
 	case DWC3_GCTL_PRTCAP_DEVICE:
@@ -1877,10 +1880,7 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
 		dwc3_core_exit(dwc);
 		break;
 	case DWC3_GCTL_PRTCAP_HOST:
-		if (!PMSG_IS_AUTO(msg)) {
-			dwc3_core_exit(dwc);
-			break;
-		}
+		dwc3_set_phy_speed_mode(dwc);
 
 		/* Let controller to suspend HSPHY before PHY driver suspends */
 		if (dwc->dis_u2_susphy_quirk ||
@@ -1896,6 +1896,16 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
 
 		phy_pm_runtime_put_sync(dwc->usb2_generic_phy);
 		phy_pm_runtime_put_sync(dwc->usb3_generic_phy);
+
+		if (!PMSG_IS_AUTO(msg)) {
+			if (device_may_wakeup(dwc->dev) &&
+			    usb_wakeup_enabled_descendants(hcd->self.root_hub)) {
+				dwc->phy_power_off = false;
+			} else {
+				dwc->phy_power_off = true;
+				dwc3_core_exit(dwc);
+			}
+		}
 		break;
 	case DWC3_GCTL_PRTCAP_OTG:
 		/* do nothing during runtime_suspend */
@@ -1939,11 +1949,12 @@ static int dwc3_resume_common(struct dwc3 *dwc, pm_message_t msg)
 		break;
 	case DWC3_GCTL_PRTCAP_HOST:
 		if (!PMSG_IS_AUTO(msg)) {
-			ret = dwc3_core_init_for_resume(dwc);
-			if (ret)
-				return ret;
-			dwc3_set_prtcap(dwc, DWC3_GCTL_PRTCAP_HOST);
-			break;
+			if (dwc->phy_power_off) {
+				ret = dwc3_core_init_for_resume(dwc);
+				if (ret)
+					return ret;
+				dwc3_set_prtcap(dwc, DWC3_GCTL_PRTCAP_HOST);
+			}
 		}
 		/* Restore GUSB2PHYCFG bits that were modified in suspend */
 		reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 5c9d467..de58995 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -1154,6 +1154,9 @@ struct dwc3 {
 
 	bool			phys_ready;
 
+	unsigned int            hs_phy_mode;
+	bool			phy_power_off;
+
 	struct ulpi		*ulpi;
 	bool			ulpi_ready;
 
@@ -1537,6 +1540,7 @@ int dwc3_core_soft_reset(struct dwc3 *dwc);
 #if IS_ENABLED(CONFIG_USB_DWC3_HOST) || IS_ENABLED(CONFIG_USB_DWC3_DUAL_ROLE)
 int dwc3_host_init(struct dwc3 *dwc);
 void dwc3_host_exit(struct dwc3 *dwc);
+void dwc3_set_phy_speed_mode(struct dwc3 *dwc);
 #else
 static inline int dwc3_host_init(struct dwc3 *dwc)
 { return 0; }
diff --git a/drivers/usb/dwc3/host.c b/drivers/usb/dwc3/host.c
index eda8719..74e7d92 100644
--- a/drivers/usb/dwc3/host.c
+++ b/drivers/usb/dwc3/host.c
@@ -13,6 +13,7 @@
 #include <linux/platform_device.h>
 
 #include "core.h"
+#include "../host/xhci.h"
 
 static void dwc3_host_fill_xhci_irq_res(struct dwc3 *dwc,
 					int irq, char *name)
@@ -138,3 +139,27 @@ void dwc3_host_exit(struct dwc3 *dwc)
 {
 	platform_device_unregister(dwc->xhci);
 }
+
+void dwc3_set_phy_speed_mode(struct dwc3 *dwc)
+{
+
+	int i, num_ports;
+	u32 reg;
+	struct usb_hcd	*hcd = platform_get_drvdata(dwc->xhci);
+	struct xhci_hcd	*xhci_hcd = hcd_to_xhci(hcd);
+
+	dwc->hs_phy_mode = 0;
+
+	reg = readl(&xhci_hcd->cap_regs->hcs_params1);
+
+	num_ports = HCS_MAX_PORTS(reg);
+	for (i = 0; i < num_ports; i++) {
+		reg = readl(&xhci_hcd->op_regs->port_status_base + i * NUM_PORT_REGS);
+		if (reg & PORT_PE) {
+			if (DEV_HIGHSPEED(reg) || DEV_FULLSPEED(reg))
+				dwc->hs_phy_mode |= PHY_MODE_USB_HOST_HS;
+			else if (DEV_LOWSPEED(reg))
+				dwc->hs_phy_mode |= PHY_MODE_USB_HOST_LS;
+		}
+	}
+}
-- 
2.7.4

[PATCH v12 2/6] usb: dwc3: qcom: Add helper functions to enable,disable wake irqs

[Sandeep Maheswaram]

Adding helper functions to enable,disable wake irqs to make
the code simple and readable.

Signed-off-by: Sandeep Maheswaram <quic_c_sanm@quicinc.com>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
---
 drivers/usb/dwc3/dwc3-qcom.c | 58 ++++++++++++++++++++------------------------
 1 file changed, 26 insertions(+), 32 deletions(-)

diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c
index 6cba990..7352124 100644
--- a/drivers/usb/dwc3/dwc3-qcom.c
+++ b/drivers/usb/dwc3/dwc3-qcom.c
@@ -296,50 +296,44 @@ static void dwc3_qcom_interconnect_exit(struct dwc3_qcom *qcom)
 	icc_put(qcom->icc_path_apps);
 }
 
+static void dwc3_qcom_enable_wakeup_irq(int irq)
+{
+	if (!irq)
+		return;
+
+	enable_irq(irq);
+	enable_irq_wake(irq);
+}
+
+static void dwc3_qcom_disable_wakeup_irq(int irq)
+{
+	if (!irq)
+		return;
+
+	disable_irq_wake(irq);
+	disable_irq_nosync(irq);
+}
+
 static void dwc3_qcom_disable_interrupts(struct dwc3_qcom *qcom)
 {
-	if (qcom->hs_phy_irq) {
-		disable_irq_wake(qcom->hs_phy_irq);
-		disable_irq_nosync(qcom->hs_phy_irq);
-	}
+	dwc3_qcom_disable_wakeup_irq(qcom->hs_phy_irq);
 
-	if (qcom->dp_hs_phy_irq) {
-		disable_irq_wake(qcom->dp_hs_phy_irq);
-		disable_irq_nosync(qcom->dp_hs_phy_irq);
-	}
+	dwc3_qcom_disable_wakeup_irq(qcom->dp_hs_phy_irq);
 
-	if (qcom->dm_hs_phy_irq) {
-		disable_irq_wake(qcom->dm_hs_phy_irq);
-		disable_irq_nosync(qcom->dm_hs_phy_irq);
-	}
+	dwc3_qcom_disable_wakeup_irq(qcom->dm_hs_phy_irq);
 
-	if (qcom->ss_phy_irq) {
-		disable_irq_wake(qcom->ss_phy_irq);
-		disable_irq_nosync(qcom->ss_phy_irq);
-	}
+	dwc3_qcom_disable_wakeup_irq(qcom->ss_phy_irq);
 }
 
 static void dwc3_qcom_enable_interrupts(struct dwc3_qcom *qcom)
 {
-	if (qcom->hs_phy_irq) {
-		enable_irq(qcom->hs_phy_irq);
-		enable_irq_wake(qcom->hs_phy_irq);
-	}
+	dwc3_qcom_enable_wakeup_irq(qcom->hs_phy_irq);
 
-	if (qcom->dp_hs_phy_irq) {
-		enable_irq(qcom->dp_hs_phy_irq);
-		enable_irq_wake(qcom->dp_hs_phy_irq);
-	}
+	dwc3_qcom_enable_wakeup_irq(qcom->dp_hs_phy_irq);
 
-	if (qcom->dm_hs_phy_irq) {
-		enable_irq(qcom->dm_hs_phy_irq);
-		enable_irq_wake(qcom->dm_hs_phy_irq);
-	}
+	dwc3_qcom_enable_wakeup_irq(qcom->dm_hs_phy_irq);
 
-	if (qcom->ss_phy_irq) {
-		enable_irq(qcom->ss_phy_irq);
-		enable_irq_wake(qcom->ss_phy_irq);
-	}
+	dwc3_qcom_enable_wakeup_irq(qcom->ss_phy_irq);
 }
 
 static int dwc3_qcom_suspend(struct dwc3_qcom *qcom)
-- 
2.7.4

[PATCH v12 3/6] usb: dwc3: qcom: Configure wakeup interrupts during suspend

[Sandeep Maheswaram]

Configure DP/DM interrupts to detect line state changes based on
hs_phy_mode. Enable the triggers opposite of what the current
DP, DM levels. For HS/FS mode enable DM interrupt and for LS enable DP
interrupt.

Signed-off-by: Sandeep Maheswaram <quic_c_sanm@quicinc.com>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
---
 drivers/usb/dwc3/dwc3-qcom.c | 26 ++++++++++++++++++++------
 1 file changed, 20 insertions(+), 6 deletions(-)

diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c
index 7352124..9804a19 100644
--- a/drivers/usb/dwc3/dwc3-qcom.c
+++ b/drivers/usb/dwc3/dwc3-qcom.c
@@ -316,22 +316,36 @@ static void dwc3_qcom_disable_wakeup_irq(int irq)
 
 static void dwc3_qcom_disable_interrupts(struct dwc3_qcom *qcom)
 {
-	dwc3_qcom_disable_wakeup_irq(qcom->hs_phy_irq);
+	struct dwc3 *dwc = platform_get_drvdata(qcom->dwc3);
 
-	dwc3_qcom_disable_wakeup_irq(qcom->dp_hs_phy_irq);
+	dwc3_qcom_disable_wakeup_irq(qcom->hs_phy_irq);
 
-	dwc3_qcom_disable_wakeup_irq(qcom->dm_hs_phy_irq);
+	if (dwc->hs_phy_mode & PHY_MODE_USB_HOST_LS) {
+		dwc3_qcom_disable_wakeup_irq(qcom->dp_hs_phy_irq);
+	} else if (dwc->hs_phy_mode & PHY_MODE_USB_HOST_HS) {
+		dwc3_qcom_disable_wakeup_irq(qcom->dm_hs_phy_irq);
+	} else {
+		dwc3_qcom_disable_wakeup_irq(qcom->dp_hs_phy_irq);
+		dwc3_qcom_disable_wakeup_irq(qcom->dm_hs_phy_irq);
+	}
 
 	dwc3_qcom_disable_wakeup_irq(qcom->ss_phy_irq);
 }
 
 static void dwc3_qcom_enable_interrupts(struct dwc3_qcom *qcom)
 {
-	dwc3_qcom_enable_wakeup_irq(qcom->hs_phy_irq);
+	struct dwc3 *dwc = platform_get_drvdata(qcom->dwc3);
 
-	dwc3_qcom_enable_wakeup_irq(qcom->dp_hs_phy_irq);
+	dwc3_qcom_enable_wakeup_irq(qcom->hs_phy_irq);
 
-	dwc3_qcom_enable_wakeup_irq(qcom->dm_hs_phy_irq);
+	if (dwc->hs_phy_mode & PHY_MODE_USB_HOST_LS) {
+		dwc3_qcom_enable_wakeup_irq(qcom->dp_hs_phy_irq);
+	} else if (dwc->hs_phy_mode & PHY_MODE_USB_HOST_HS) {
+		dwc3_qcom_enable_wakeup_irq(qcom->dm_hs_phy_irq);
+	} else {
+		dwc3_qcom_enable_wakeup_irq(qcom->dp_hs_phy_irq);
+		dwc3_qcom_enable_wakeup_irq(qcom->dm_hs_phy_irq);
+	}
 
 	dwc3_qcom_enable_wakeup_irq(qcom->ss_phy_irq);
 }
-- 
2.7.4

[PATCH v12 4/6] usb: dwc3: qcom: Keep power domain on to retain controller status

[Sandeep Maheswaram]

Keep the power domain on in order to retain controller status and
to support wakeup from devices.

Signed-off-by: Sandeep Maheswaram <quic_c_sanm@quicinc.com>
---
 drivers/usb/dwc3/dwc3-qcom.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c
index 9804a19..35087cf 100644
--- a/drivers/usb/dwc3/dwc3-qcom.c
+++ b/drivers/usb/dwc3/dwc3-qcom.c
@@ -17,6 +17,7 @@
 #include <linux/of_platform.h>
 #include <linux/platform_device.h>
 #include <linux/phy/phy.h>
+#include <linux/pm_domain.h>
 #include <linux/usb/of.h>
 #include <linux/reset.h>
 #include <linux/iopoll.h>
@@ -724,6 +725,7 @@ static int dwc3_qcom_probe(struct platform_device *pdev)
 	struct resource		*res, *parent_res = NULL;
 	int			ret, i;
 	bool			ignore_pipe_clk;
+	struct generic_pm_domain *genpd;
 
 	qcom = devm_kzalloc(&pdev->dev, sizeof(*qcom), GFP_KERNEL);
 	if (!qcom)
@@ -732,6 +734,8 @@ static int dwc3_qcom_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, qcom);
 	qcom->dev = &pdev->dev;
 
+	genpd = pd_to_genpd(qcom->dev->pm_domain);
+
 	if (has_acpi_companion(dev)) {
 		qcom->acpi_pdata = acpi_device_get_match_data(dev);
 		if (!qcom->acpi_pdata) {
@@ -839,6 +843,8 @@ static int dwc3_qcom_probe(struct platform_device *pdev)
 	if (ret)
 		goto interconnect_exit;
 
+	genpd->flags |= GENPD_FLAG_ALWAYS_ON;
+
 	device_init_wakeup(&pdev->dev, 1);
 	qcom->is_suspended = false;
 	pm_runtime_set_active(dev);
-- 
2.7.4

[PATCH v12 5/6] dt-bindings: usb: dwc3: Add wakeup-source property support

[Sandeep Maheswaram]

Added support for wakeup-source property. This property can be
used to check and power down the phy during system suspend if
wake up is not supported.

Signed-off-by: Sandeep Maheswaram <quic_c_sanm@quicinc.com>
---
 Documentation/devicetree/bindings/usb/snps,dwc3.yaml | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/Documentation/devicetree/bindings/usb/snps,dwc3.yaml b/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
index f4471f8..4d4de2f 100644
--- a/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
+++ b/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
@@ -341,6 +341,11 @@ properties:
       This port is used with the 'usb-role-switch' property  to connect the
       dwc3 to type C connector.
 
+  wakeup-source:
+    $ref: /schemas/types.yaml#/definitions/flag
+    description:
+      Enable USB remote wakeup.
+
 unevaluatedProperties: false
 
 required:
-- 
2.7.4

[PATCH v12 6/6] arm64: dts: qcom: sc7280: Add wakeup-source property for USB node

[Sandeep Maheswaram]

Adding wakeup-source property for USB controller in SC7280.
This property is added to inform that the USB controller is
wake up capable and to conditionally power down the phy during
system suspend.

Signed-off-by: Sandeep Maheswaram <quic_c_sanm@quicinc.com>
---
 arch/arm64/boot/dts/qcom/sc7280.dtsi | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/boot/dts/qcom/sc7280.dtsi b/arch/arm64/boot/dts/qcom/sc7280.dtsi
index f0b64be..046262a 100644
--- a/arch/arm64/boot/dts/qcom/sc7280.dtsi
+++ b/arch/arm64/boot/dts/qcom/sc7280.dtsi
@@ -2916,6 +2916,7 @@
 				phys = <&usb_1_hsphy>, <&usb_1_ssphy>;
 				phy-names = "usb2-phy", "usb3-phy";
 				maximum-speed = "super-speed";
+				wakeup-source;
 			};
 		};
 
-- 
2.7.4

Re: [PATCH v12 5/6] dt-bindings: usb: dwc3: Add wakeup-source property support

[Matthias Kaehlcke]

On Thu, Apr 07, 2022 at 02:15:03PM +0530, Sandeep Maheswaram wrote:
> Added support for wakeup-source property. This property can be
> used to check and power down the phy during system suspend if
> wake up is not supported.
> 
> Signed-off-by: Sandeep Maheswaram <quic_c_sanm@quicinc.com>
> ---
>  Documentation/devicetree/bindings/usb/snps,dwc3.yaml | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/usb/snps,dwc3.yaml b/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
> index f4471f8..4d4de2f 100644
> --- a/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
> +++ b/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
> @@ -341,6 +341,11 @@ properties:
>        This port is used with the 'usb-role-switch' property  to connect the
>        dwc3 to type C connector.
>  
> +  wakeup-source:
> +    $ref: /schemas/types.yaml#/definitions/flag
> +    description:
> +      Enable USB remote wakeup.
> +
>  unevaluatedProperties: false
>  
>  required:

nit: within the series this patch should be before "dt-bindings: usb: dwc3:
Add wakeup-source property support", which makes use of the new property.
If you have to re-spin for another reason please change the order.

Reviewed-by: Matthias Kaehlcke <mka@chromium.org>

Re: [PATCH v12 1/6] usb: dwc3: core: Host wake up support from system suspend

[Matthias Kaehlcke]

On Thu, Apr 07, 2022 at 02:14:59PM +0530, Sandeep Maheswaram wrote:
> During suspend read the status of all port and set hs phy mode
> based on current speed. Use this hs phy mode to configure wakeup
> interrupts in qcom glue driver.
> 
> Also check during suspend if any wakeup capable devices are
> connected to the controller (directly or through hubs), if there
> are none set a flag to indicate that the PHY is powered
> down during suspend.
> 
> Signed-off-by: Sandeep Maheswaram <quic_c_sanm@quicinc.com>
> ---
>  drivers/usb/dwc3/core.c | 29 ++++++++++++++++++++---------
>  drivers/usb/dwc3/core.h |  4 ++++
>  drivers/usb/dwc3/host.c | 25 +++++++++++++++++++++++++
>  3 files changed, 49 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index 1170b80..b102a22 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -32,6 +32,7 @@
>  #include <linux/usb/gadget.h>
>  #include <linux/usb/of.h>
>  #include <linux/usb/otg.h>
> +#include <linux/usb/hcd.h>
>  
>  #include "core.h"
>  #include "gadget.h"
> @@ -1723,6 +1724,7 @@ static int dwc3_probe(struct platform_device *pdev)
>  
>  	platform_set_drvdata(pdev, dwc);
>  	dwc3_cache_hwparams(dwc);
> +	device_init_wakeup(&pdev->dev, of_property_read_bool(dev->of_node, "wakeup-source"));
>  
>  	spin_lock_init(&dwc->lock);
>  	mutex_init(&dwc->mutex);
> @@ -1865,6 +1867,7 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
>  {
>  	unsigned long	flags;
>  	u32 reg;
> +	struct usb_hcd  *hcd = platform_get_drvdata(dwc->xhci);
>  
>  	switch (dwc->current_dr_role) {
>  	case DWC3_GCTL_PRTCAP_DEVICE:
> @@ -1877,10 +1880,7 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
>  		dwc3_core_exit(dwc);
>  		break;
>  	case DWC3_GCTL_PRTCAP_HOST:
> -		if (!PMSG_IS_AUTO(msg)) {
> -			dwc3_core_exit(dwc);
> -			break;
> -		}
> +		dwc3_set_phy_speed_mode(dwc);
>  
>  		/* Let controller to suspend HSPHY before PHY driver suspends */
>  		if (dwc->dis_u2_susphy_quirk ||
> @@ -1896,6 +1896,16 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
>  
>  		phy_pm_runtime_put_sync(dwc->usb2_generic_phy);
>  		phy_pm_runtime_put_sync(dwc->usb3_generic_phy);
> +
> +		if (!PMSG_IS_AUTO(msg)) {
> +			if (device_may_wakeup(dwc->dev) &&
> +			    usb_wakeup_enabled_descendants(hcd->self.root_hub)) {

Did you ever try whether you could use device_children_wakeup_capable() from
[1] instead of usb_wakeup_enabled_descendants()?

[1] https://patchwork.kernel.org/project/linux-usb/patch/1635753224-23975-2-git-send-email-quic_c_sanm@quicinc.com/#24566065

> +				dwc->phy_power_off = false;
> +			} else {
> +				dwc->phy_power_off = true;
> +				dwc3_core_exit(dwc);
> +			}
> +		}
>  		break;
>  	case DWC3_GCTL_PRTCAP_OTG:
>  		/* do nothing during runtime_suspend */
> @@ -1939,11 +1949,12 @@ static int dwc3_resume_common(struct dwc3 *dwc, pm_message_t msg)
>  		break;
>  	case DWC3_GCTL_PRTCAP_HOST:
>  		if (!PMSG_IS_AUTO(msg)) {
> -			ret = dwc3_core_init_for_resume(dwc);
> -			if (ret)
> -				return ret;
> -			dwc3_set_prtcap(dwc, DWC3_GCTL_PRTCAP_HOST);
> -			break;
> +			if (dwc->phy_power_off) {
> +				ret = dwc3_core_init_for_resume(dwc);
> +				if (ret)
> +					return ret;
> +				dwc3_set_prtcap(dwc, DWC3_GCTL_PRTCAP_HOST);
> +			}
>  		}
>  		/* Restore GUSB2PHYCFG bits that were modified in suspend */
>  		reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
> diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
> index 5c9d467..de58995 100644
> --- a/drivers/usb/dwc3/core.h
> +++ b/drivers/usb/dwc3/core.h
> @@ -1154,6 +1154,9 @@ struct dwc3 {
>  
>  	bool			phys_ready;
>  
> +	unsigned int            hs_phy_mode;
> +	bool			phy_power_off;
> +
>  	struct ulpi		*ulpi;
>  	bool			ulpi_ready;
>  
> @@ -1537,6 +1540,7 @@ int dwc3_core_soft_reset(struct dwc3 *dwc);
>  #if IS_ENABLED(CONFIG_USB_DWC3_HOST) || IS_ENABLED(CONFIG_USB_DWC3_DUAL_ROLE)
>  int dwc3_host_init(struct dwc3 *dwc);
>  void dwc3_host_exit(struct dwc3 *dwc);
> +void dwc3_set_phy_speed_mode(struct dwc3 *dwc);
>  #else
>  static inline int dwc3_host_init(struct dwc3 *dwc)
>  { return 0; }
> diff --git a/drivers/usb/dwc3/host.c b/drivers/usb/dwc3/host.c
> index eda8719..74e7d92 100644
> --- a/drivers/usb/dwc3/host.c
> +++ b/drivers/usb/dwc3/host.c
> @@ -13,6 +13,7 @@
>  #include <linux/platform_device.h>
>  
>  #include "core.h"
> +#include "../host/xhci.h"
>  
>  static void dwc3_host_fill_xhci_irq_res(struct dwc3 *dwc,
>  					int irq, char *name)
> @@ -138,3 +139,27 @@ void dwc3_host_exit(struct dwc3 *dwc)
>  {
>  	platform_device_unregister(dwc->xhci);
>  }
> +
> +void dwc3_set_phy_speed_mode(struct dwc3 *dwc)

IMO the name is a bit confusing, it suggests that the speed at which
the PHY operates is changed, which isn't the case. I suggest to change
the name to dwc3_determine_phy_speed_mode() (or something similar).

> +{
> +
> +	int i, num_ports;
> +	u32 reg;
> +	struct usb_hcd	*hcd = platform_get_drvdata(dwc->xhci);
> +	struct xhci_hcd	*xhci_hcd = hcd_to_xhci(hcd);
> +
> +	dwc->hs_phy_mode = 0;
> +
> +	reg = readl(&xhci_hcd->cap_regs->hcs_params1);
> +
> +	num_ports = HCS_MAX_PORTS(reg);
> +	for (i = 0; i < num_ports; i++) {
> +		reg = readl(&xhci_hcd->op_regs->port_status_base + i * NUM_PORT_REGS);
> +		if (reg & PORT_PE) {
> +			if (DEV_HIGHSPEED(reg) || DEV_FULLSPEED(reg))
> +				dwc->hs_phy_mode |= PHY_MODE_USB_HOST_HS;
> +			else if (DEV_LOWSPEED(reg))
> +				dwc->hs_phy_mode |= PHY_MODE_USB_HOST_LS;
> +		}
> +	}
> +}
> -- 
> 2.7.4
> 

Re: [PATCH v12 4/6] usb: dwc3: qcom: Keep power domain on to retain controller status

[Matthias Kaehlcke]

On Thu, Apr 07, 2022 at 02:15:02PM +0530, Sandeep Maheswaram wrote:
> Keep the power domain on in order to retain controller status and
> to support wakeup from devices.
> 
> Signed-off-by: Sandeep Maheswaram <quic_c_sanm@quicinc.com>
> ---
>  drivers/usb/dwc3/dwc3-qcom.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c
> index 9804a19..35087cf 100644
> --- a/drivers/usb/dwc3/dwc3-qcom.c
> +++ b/drivers/usb/dwc3/dwc3-qcom.c
> @@ -17,6 +17,7 @@
>  #include <linux/of_platform.h>
>  #include <linux/platform_device.h>
>  #include <linux/phy/phy.h>
> +#include <linux/pm_domain.h>
>  #include <linux/usb/of.h>
>  #include <linux/reset.h>
>  #include <linux/iopoll.h>
> @@ -724,6 +725,7 @@ static int dwc3_qcom_probe(struct platform_device *pdev)
>  	struct resource		*res, *parent_res = NULL;
>  	int			ret, i;
>  	bool			ignore_pipe_clk;
> +	struct generic_pm_domain *genpd;
>  
>  	qcom = devm_kzalloc(&pdev->dev, sizeof(*qcom), GFP_KERNEL);
>  	if (!qcom)
> @@ -732,6 +734,8 @@ static int dwc3_qcom_probe(struct platform_device *pdev)
>  	platform_set_drvdata(pdev, qcom);
>  	qcom->dev = &pdev->dev;
>  
> +	genpd = pd_to_genpd(qcom->dev->pm_domain);
> +
>  	if (has_acpi_companion(dev)) {
>  		qcom->acpi_pdata = acpi_device_get_match_data(dev);
>  		if (!qcom->acpi_pdata) {
> @@ -839,6 +843,8 @@ static int dwc3_qcom_probe(struct platform_device *pdev)
>  	if (ret)
>  		goto interconnect_exit;
>  
> +	genpd->flags |= GENPD_FLAG_ALWAYS_ON;

Not sure it really matters, but could this be done conditionally based
on device_can_wakeup() of the dwc3 core device?

> +
>  	device_init_wakeup(&pdev->dev, 1);

Now that the dwc3 core looks at the wakeup-source property it seems
this driver should enable wakeup only when it is enabled for the
core.

Actually I wonder if it would make sense to leave wakeup for dwc3-qcom
'officially' disabled, and just make all wakeup related decisions
based on the wakeup configuration of the dwc3 core (as
dwc3_qcom_en/disable_interrupts() already do). The separate wakeup
policies for dwc3 core and dwc3-qcom are confusing and don't seem to
add any value.

Re: [PATCH v12 6/6] arm64: dts: qcom: sc7280: Add wakeup-source property for USB node

[Matthias Kaehlcke]

On Thu, Apr 07, 2022 at 02:15:04PM +0530, Sandeep Maheswaram wrote:
> Adding wakeup-source property for USB controller in SC7280.
> This property is added to inform that the USB controller is
> wake up capable and to conditionally power down the phy during
> system suspend.
> 
> Signed-off-by: Sandeep Maheswaram <quic_c_sanm@quicinc.com>
> ---
>  arch/arm64/boot/dts/qcom/sc7280.dtsi | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/arm64/boot/dts/qcom/sc7280.dtsi b/arch/arm64/boot/dts/qcom/sc7280.dtsi
> index f0b64be..046262a 100644
> --- a/arch/arm64/boot/dts/qcom/sc7280.dtsi
> +++ b/arch/arm64/boot/dts/qcom/sc7280.dtsi
> @@ -2916,6 +2916,7 @@
>  				phys = <&usb_1_hsphy>, <&usb_1_ssphy>;
>  				phy-names = "usb2-phy", "usb3-phy";
>  				maximum-speed = "super-speed";
> +				wakeup-source;
>  			};
>  		};

Not all SC7280 boards may want to enable wakeup from USB, so this is
probably best configured on a per-board basis.

Re: [PATCH v12 4/6] usb: dwc3: qcom: Keep power domain on to retain controller status

[Pavan Kondeti]

On Thu, Apr 07, 2022 at 11:01:57AM -0700, Matthias Kaehlcke wrote:
> On Thu, Apr 07, 2022 at 02:15:02PM +0530, Sandeep Maheswaram wrote:
> > Keep the power domain on in order to retain controller status and
> > to support wakeup from devices.
> > 
> > Signed-off-by: Sandeep Maheswaram <quic_c_sanm@quicinc.com>
> > ---
> >  drivers/usb/dwc3/dwc3-qcom.c | 6 ++++++
> >  1 file changed, 6 insertions(+)
> > 
> > diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c
> > index 9804a19..35087cf 100644
> > --- a/drivers/usb/dwc3/dwc3-qcom.c
> > +++ b/drivers/usb/dwc3/dwc3-qcom.c
> > @@ -17,6 +17,7 @@
> >  #include <linux/of_platform.h>
> >  #include <linux/platform_device.h>
> >  #include <linux/phy/phy.h>
> > +#include <linux/pm_domain.h>
> >  #include <linux/usb/of.h>
> >  #include <linux/reset.h>
> >  #include <linux/iopoll.h>
> > @@ -724,6 +725,7 @@ static int dwc3_qcom_probe(struct platform_device *pdev)
> >  	struct resource		*res, *parent_res = NULL;
> >  	int			ret, i;
> >  	bool			ignore_pipe_clk;
> > +	struct generic_pm_domain *genpd;
> >  
> >  	qcom = devm_kzalloc(&pdev->dev, sizeof(*qcom), GFP_KERNEL);
> >  	if (!qcom)
> > @@ -732,6 +734,8 @@ static int dwc3_qcom_probe(struct platform_device *pdev)
> >  	platform_set_drvdata(pdev, qcom);
> >  	qcom->dev = &pdev->dev;
> >  
> > +	genpd = pd_to_genpd(qcom->dev->pm_domain);
> > +
> >  	if (has_acpi_companion(dev)) {
> >  		qcom->acpi_pdata = acpi_device_get_match_data(dev);
> >  		if (!qcom->acpi_pdata) {
> > @@ -839,6 +843,8 @@ static int dwc3_qcom_probe(struct platform_device *pdev)
> >  	if (ret)
> >  		goto interconnect_exit;
> >  
> > +	genpd->flags |= GENPD_FLAG_ALWAYS_ON;
> 
> Not sure it really matters, but could this be done conditionally based
> on device_can_wakeup() of the dwc3 core device?

+1. Makes sense to me.

> 
> > +
> >  	device_init_wakeup(&pdev->dev, 1);
> 
> Now that the dwc3 core looks at the wakeup-source property it seems
> this driver should enable wakeup only when it is enabled for the
> core.
> 
> Actually I wonder if it would make sense to leave wakeup for dwc3-qcom
> 'officially' disabled, and just make all wakeup related decisions
> based on the wakeup configuration of the dwc3 core (as
> dwc3_qcom_en/disable_interrupts() already do). The separate wakeup
> policies for dwc3 core and dwc3-qcom are confusing and don't seem to
> add any value.

This suggestion makes sense. Do we foresee any issues by not marking
this parent device not wakeup capable? I don't see any.

Thanks,
Pavan

Re: [PATCH v12 6/6] arm64: dts: qcom: sc7280: Add wakeup-source property for USB node

[Pavan Kondeti]

On Thu, Apr 07, 2022 at 11:06:40AM -0700, Matthias Kaehlcke wrote:
> On Thu, Apr 07, 2022 at 02:15:04PM +0530, Sandeep Maheswaram wrote:
> > Adding wakeup-source property for USB controller in SC7280.
> > This property is added to inform that the USB controller is
> > wake up capable and to conditionally power down the phy during
> > system suspend.
> > 
> > Signed-off-by: Sandeep Maheswaram <quic_c_sanm@quicinc.com>
> > ---
> >  arch/arm64/boot/dts/qcom/sc7280.dtsi | 1 +
> >  1 file changed, 1 insertion(+)
> > 
> > diff --git a/arch/arm64/boot/dts/qcom/sc7280.dtsi b/arch/arm64/boot/dts/qcom/sc7280.dtsi
> > index f0b64be..046262a 100644
> > --- a/arch/arm64/boot/dts/qcom/sc7280.dtsi
> > +++ b/arch/arm64/boot/dts/qcom/sc7280.dtsi
> > @@ -2916,6 +2916,7 @@
> >  				phys = <&usb_1_hsphy>, <&usb_1_ssphy>;
> >  				phy-names = "usb2-phy", "usb3-phy";
> >  				maximum-speed = "super-speed";
> > +				wakeup-source;
> >  			};
> >  		};
> 
> Not all SC7280 boards may want to enable wakeup from USB, so this is
> probably best configured on a per-board basis.

This wakeup capability is provided by the SoC. If a particular
board does not want to support, ideally it needs to be disabled from
user space. The capability is always there but some platforms choose to
disable it.

Thanks,
Pavan

Re: [PATCH v12 6/6] arm64: dts: qcom: sc7280: Add wakeup-source property for USB node

[Matthias Kaehlcke]

On Fri, Apr 08, 2022 at 07:32:39AM +0530, Pavan Kondeti wrote:
> On Thu, Apr 07, 2022 at 11:06:40AM -0700, Matthias Kaehlcke wrote:
> > On Thu, Apr 07, 2022 at 02:15:04PM +0530, Sandeep Maheswaram wrote:
> > > Adding wakeup-source property for USB controller in SC7280.
> > > This property is added to inform that the USB controller is
> > > wake up capable and to conditionally power down the phy during
> > > system suspend.
> > > 
> > > Signed-off-by: Sandeep Maheswaram <quic_c_sanm@quicinc.com>
> > > ---
> > >  arch/arm64/boot/dts/qcom/sc7280.dtsi | 1 +
> > >  1 file changed, 1 insertion(+)
> > > 
> > > diff --git a/arch/arm64/boot/dts/qcom/sc7280.dtsi b/arch/arm64/boot/dts/qcom/sc7280.dtsi
> > > index f0b64be..046262a 100644
> > > --- a/arch/arm64/boot/dts/qcom/sc7280.dtsi
> > > +++ b/arch/arm64/boot/dts/qcom/sc7280.dtsi
> > > @@ -2916,6 +2916,7 @@
> > >  				phys = <&usb_1_hsphy>, <&usb_1_ssphy>;
> > >  				phy-names = "usb2-phy", "usb3-phy";
> > >  				maximum-speed = "super-speed";
> > > +				wakeup-source;
> > >  			};
> > >  		};
> > 
> > Not all SC7280 boards may want to enable wakeup from USB, so this is
> > probably best configured on a per-board basis.
> 
> This wakeup capability is provided by the SoC. If a particular
> board does not want to support, ideally it needs to be disabled from
> user space. The capability is always there but some platforms choose to
> disable it.

I guess 'wakeup-source' is a bit of an edge case between hardware capability
(which is certainly required to make wakeup work) and policy.

arch/arm64/boot/dts/mediatek/mt2712-evb.dts and
arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi are two example where
'wakeup-source' is set at the board level for a USB controller.

It's also true that user space can disable wakeup as you said, and a board
could also delete the property in its device tree if desired.

With that I agree that setting 'wakeup-source' at the SoC level provides
more flexibility and is more in line with the DT as hardware description.

Reviewed-by: Matthias Kaehlcke <mka@chromium.org>

Re: [PATCH v12 1/6] usb: dwc3: core: Host wake up support from system suspend

[Pavan Kondeti]

On Thu, Apr 07, 2022 at 02:14:59PM +0530, Sandeep Maheswaram wrote:
> During suspend read the status of all port and set hs phy mode
> based on current speed. Use this hs phy mode to configure wakeup
> interrupts in qcom glue driver.
> 
> Also check during suspend if any wakeup capable devices are
> connected to the controller (directly or through hubs), if there
> are none set a flag to indicate that the PHY is powered
> down during suspend.
> 
> Signed-off-by: Sandeep Maheswaram <quic_c_sanm@quicinc.com>
> ---
>  drivers/usb/dwc3/core.c | 29 ++++++++++++++++++++---------
>  drivers/usb/dwc3/core.h |  4 ++++
>  drivers/usb/dwc3/host.c | 25 +++++++++++++++++++++++++
>  3 files changed, 49 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index 1170b80..b102a22 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -32,6 +32,7 @@
>  #include <linux/usb/gadget.h>
>  #include <linux/usb/of.h>
>  #include <linux/usb/otg.h>
> +#include <linux/usb/hcd.h>
>  
>  #include "core.h"
>  #include "gadget.h"
> @@ -1723,6 +1724,7 @@ static int dwc3_probe(struct platform_device *pdev)
>  
>  	platform_set_drvdata(pdev, dwc);
>  	dwc3_cache_hwparams(dwc);
> +	device_init_wakeup(&pdev->dev, of_property_read_bool(dev->of_node, "wakeup-source"));

The current code calls device_init_wakeup(true) in runtime suspend and calls
device_init_wakeup(false) in runtime resume. We don't want that right now
given that we have a this new dT property. can you fix this please?

Thanks,
Pavan