Hi Felipe, On 28 November 2016 at 14:43, Baolin Wang <baolin.w...@linaro.org> wrote: > 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. > > Signed-off-by: Baolin Wang <baolin.w...@linaro.org> > --- > Changes since v3: > - No updates. > > Changes since v2: > - Remove pm_children_suspended() and other unused macros. > > Changes since v1: > - Add pm_runtime.h head file to avoid kbuild error. > --- > drivers/usb/dwc3/Kconfig | 7 +++++++ > drivers/usb/dwc3/core.c | 26 +++++++++++++++++++++++++- > drivers/usb/dwc3/core.h | 15 +++++++++++++++ > drivers/usb/dwc3/host.c | 37 +++++++++++++++++++++++++++++++++++++ > 4 files changed, 84 insertions(+), 1 deletion(-) > > diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig > index a45b4f1..47bb2f3 100644 > --- a/drivers/usb/dwc3/Kconfig > +++ b/drivers/usb/dwc3/Kconfig > @@ -47,6 +47,13 @@ config USB_DWC3_DUAL_ROLE > > endchoice > > +config USB_DWC3_HOST_SUSPEND > + bool "Choose if the DWC3 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. > + > comment "Platform Glue Driver Support" > > config USB_DWC3_OMAP > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c > index 9a4a5e4..7ad4bc3 100644 > --- a/drivers/usb/dwc3/core.c > +++ b/drivers/usb/dwc3/core.c > @@ -1091,6 +1091,7 @@ static int dwc3_probe(struct platform_device *pdev) > pm_runtime_use_autosuspend(dev); > pm_runtime_set_autosuspend_delay(dev, DWC3_DEFAULT_AUTOSUSPEND_DELAY); > pm_runtime_enable(dev); > + pm_suspend_ignore_children(dev, true); > ret = pm_runtime_get_sync(dev); > if (ret < 0) > goto err1; > @@ -1215,15 +1216,27 @@ 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; > @@ -1245,12 +1258,23 @@ 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 b585a30..db41908 100644 > --- a/drivers/usb/dwc3/core.h > +++ b/drivers/usb/dwc3/core.h > @@ -1226,4 +1226,19 @@ static inline void dwc3_ulpi_exit(struct dwc3 *dwc) > { } > #endif > > +#if IS_ENABLED(CONFIG_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 ed82464..8e5309d6 100644 > --- a/drivers/usb/dwc3/host.c > +++ b/drivers/usb/dwc3/host.c > @@ -16,6 +16,7 @@ > */ > > #include <linux/platform_device.h> > +#include <linux/pm_runtime.h> > > #include "core.h" > > @@ -130,3 +131,39 @@ void dwc3_host_exit(struct dwc3 *dwc) > dev_name(&dwc->xhci->dev)); > platform_device_unregister(dwc->xhci); > } > + > +#ifdef CONFIG_USB_DWC3_HOST_SUSPEND > +int dwc3_host_suspend(struct dwc3 *dwc) > +{ > + struct device *xhci = &dwc->xhci->dev; > + int ret; > + > + /* > + * Note: if we get the -EBUSY, which means the xHCI children devices > are > + * not in suspend state yet, the glue layer need to wait for a while > and > + * try to suspend xHCI device again. > + */ > + ret = pm_runtime_put_sync(xhci); > + if (ret) { > + dev_err(xhci, "failed to suspend xHCI device\n"); > + return ret; > + } > + > + return 0; > +} > + > +int dwc3_host_resume(struct dwc3 *dwc) > +{ > + struct device *xhci = &dwc->xhci->dev; > + int ret; > + > + /* Resume the xHCI device synchronously. */ > + ret = pm_runtime_get_sync(xhci); > + if (ret) { > + dev_err(xhci, "failed to resume xHCI device\n"); > + return ret; > + } > + > + return 0; > +} > +#endif > -- > 1.7.9.5 >
How do you think this patch and do you have any suggestion? Thanks. -- Baolin.wang Best Regards -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html