For some mobile devices with strict power management, we also want to suspend
the host when the slave is detached for power saving.
Thus we add the host suspend/resume functions to support this requirement, and
we also should enable the 'XHCI_SLOW_SUSPEND' quirk for extraordinary delay when
suspending the xhci.
Signed-off-by: Baolin Wang <baolin.w...@linaro.org>
---
drivers/usb/dwc3/Kconfig | 7 +++++++
drivers/usb/dwc3/core.c | 25 ++++++++++++++++++++++++-
drivers/usb/dwc3/core.h | 15 +++++++++++++++
drivers/usb/dwc3/host.c | 32 ++++++++++++++++++++++++++++++++
4 files changed, 78 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig
index a64ce1c..725d2bd 100644
--- a/drivers/usb/dwc3/Kconfig
+++ b/drivers/usb/dwc3/Kconfig
@@ -45,6 +45,13 @@ config USB_DWC3_DUAL_ROLE
This is the default mode of working of DWC3 controller where
both host and gadget features are enabled.
+config USB_DWC3_HOST_SUSPEND
+ bool "Choose if the host (xhci) can be suspend/resume"
+ depends on USB_DWC3_HOST=y || USB_DWC3_DUAL_ROLE=y
+ help
+ We can suspend the host when the slave is detached for power saving,
+ and resume the host when one slave is attached.
+
endchoice
comment "Platform Glue Driver Support"
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 1485480..5140b4d 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -1103,15 +1103,27 @@ static int dwc3_remove(struct platform_device *pdev)
static int dwc3_suspend_common(struct dwc3 *dwc)
{
unsigned long flags;
+ int ret;
switch (dwc->dr_mode) {
case USB_DR_MODE_PERIPHERAL:
+ spin_lock_irqsave(&dwc->lock, flags);
+ dwc3_gadget_suspend(dwc);
+ spin_unlock_irqrestore(&dwc->lock, flags);
+ break;
case USB_DR_MODE_OTG:
+ ret = dwc3_host_suspend(dwc);
+ if (ret)
+ return ret;
+
spin_lock_irqsave(&dwc->lock, flags);
dwc3_gadget_suspend(dwc);
spin_unlock_irqrestore(&dwc->lock, flags);
break;
case USB_DR_MODE_HOST:
+ ret = dwc3_host_suspend(dwc);
+ if (ret)
+ return ret;
default:
/* do nothing */
break;
@@ -1133,12 +1145,23 @@ static int dwc3_resume_common(struct dwc3 *dwc)
switch (dwc->dr_mode) {
case USB_DR_MODE_PERIPHERAL:
+ spin_lock_irqsave(&dwc->lock, flags);
+ dwc3_gadget_resume(dwc);
+ spin_unlock_irqrestore(&dwc->lock, flags);
+ break;
case USB_DR_MODE_OTG:
+ ret = dwc3_host_resume(dwc);
+ if (ret)
+ return ret;
+
spin_lock_irqsave(&dwc->lock, flags);
dwc3_gadget_resume(dwc);
spin_unlock_irqrestore(&dwc->lock, flags);
- /* FALLTHROUGH */
+ break;
case USB_DR_MODE_HOST:
+ ret = dwc3_host_resume(dwc);
+ if (ret)
+ return ret;
default:
/* do nothing */
break;
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 45d6de5..0ba203e 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -1177,4 +1177,19 @@ static inline void dwc3_ulpi_exit(struct dwc3 *dwc)
{ }
#endif
+#if IS_ENABLED(USB_DWC3_HOST_SUSPEND)
+int dwc3_host_suspend(struct dwc3 *dwc);
+int dwc3_host_resume(struct dwc3 *dwc);
+#else
+static inline int dwc3_host_suspend(struct dwc3 *dwc)
+{
+ return 0;
+}
+
+static inline int dwc3_host_resume(struct dwc3 *dwc)
+{
+ return 0;
+}
+#endif
+
#endif /* __DRIVERS_USB_DWC3_CORE_H */
diff --git a/drivers/usb/dwc3/host.c b/drivers/usb/dwc3/host.c
index 2e960ed..2ec3eff 100644
--- a/drivers/usb/dwc3/host.c
+++ b/drivers/usb/dwc3/host.c
@@ -17,8 +17,11 @@
#include <linux/platform_device.h>
#include <linux/usb/xhci_pdriver.h>
+#include <linux/usb.h>
+#include <linux/usb/hcd.h>
#include "core.h"
+#include "../host/xhci.h"
int dwc3_host_init(struct dwc3 *dwc)
{
@@ -91,6 +94,8 @@ int dwc3_host_init(struct dwc3 *dwc)
memset(&pdata, 0, sizeof(pdata));
pdata.usb3_lpm_capable = dwc->usb3_lpm_capable;
+ /* dwc3 controller need an extraordinary delay when suspending xhci. */
+ pdata.usb3_slow_suspend = 1;
ret = platform_device_add_data(xhci, &pdata, sizeof(pdata));
if (ret) {
@@ -128,3 +133,30 @@ void dwc3_host_exit(struct dwc3 *dwc)
dev_name(&dwc->xhci->dev));
platform_device_unregister(dwc->xhci);
}
+
+int dwc3_host_suspend(struct dwc3 *dwc)
+{
+ struct usb_hcd *hcd = dev_get_drvdata(&dwc->xhci->dev);
+ struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+ int ret, cnt = 20;
+
+try_again:
+ /* We should wait for xhci bus has been into suspend mode firstly. */
+ ret = xhci_suspend(xhci, device_may_wakeup(&dwc->xhci->dev));
+ if (ret && --cnt > 0) {
+ dev_warn(dwc->dev, "xhci suspend failed %d, try again...\n",
+ ret);
+ msleep(200);
+ goto try_again;
+ }
+
+ return ret;
+}
+
+int dwc3_host_resume(struct dwc3 *dwc)
+{
+ struct usb_hcd *hcd = dev_get_drvdata(&dwc->xhci->dev);
+ struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+
+ return xhci_resume(xhci, 0);
+}
--
1.7.9.5
