hi,
On Wed, 2018-10-17 at 18:29 -0400, Al Cooper wrote:
> Add the ability to skip calling the PHY's exit routine on suspend
> and the PHY's init routine on resume. This is to handle a USB PHY
> that should have it's power_off function called on suspend but cannot
> have it's exit function called because on exit it will disable the
> PHY to the point where register accesses to the Host Controllers
> using the PHY will be disabled and the host drivers will crash.
>
> This is enabled with the HCD flag "suspend_without_phy_exit" which
> can be set from any HCD driver.
>
> Signed-off-by: Al Cooper <alcooperx@xxxxxxxxx>
> ---
> drivers/usb/core/hcd.c | 8 ++++----
> drivers/usb/core/phy.c | 18 ++++++++++++------
> drivers/usb/core/phy.h | 9 ++++++---
> include/linux/usb/hcd.h | 3 +++
> 4 files changed, 25 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
> index 1c21955fe7c0..e67e4d6b3d21 100644
> --- a/drivers/usb/core/hcd.c
> +++ b/drivers/usb/core/hcd.c
> @@ -2263,7 +2263,7 @@ int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
> hcd->state = HC_STATE_SUSPENDED;
>
> if (!PMSG_IS_AUTO(msg))
> - usb_phy_roothub_suspend(hcd->self.sysdev,
> + usb_phy_roothub_suspend(hcd,
> hcd->phy_roothub);
>
> /* Did we race with a root-hub wakeup event? */
> @@ -2304,7 +2304,7 @@ int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
> }
>
> if (!PMSG_IS_AUTO(msg)) {
> - status = usb_phy_roothub_resume(hcd->self.sysdev,
> + status = usb_phy_roothub_resume(hcd,
> hcd->phy_roothub);
> if (status)
> return status;
> @@ -2347,7 +2347,7 @@ int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
> }
> } else {
> hcd->state = old_state;
> - usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub);
> + usb_phy_roothub_suspend(hcd, hcd->phy_roothub);
> dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
> "resume", status);
> if (status != -ESHUTDOWN)
> @@ -2744,7 +2744,7 @@ int usb_add_hcd(struct usb_hcd *hcd,
> struct usb_device *rhdev;
>
> if (!hcd->skip_phy_initialization && usb_hcd_is_primary_hcd(hcd)) {
> - hcd->phy_roothub = usb_phy_roothub_alloc(hcd->self.sysdev);
> + hcd->phy_roothub = usb_phy_roothub_alloc(hcd);
> if (IS_ERR(hcd->phy_roothub))
> return PTR_ERR(hcd->phy_roothub);
>
> diff --git a/drivers/usb/core/phy.c b/drivers/usb/core/phy.c
> index 9879767452a2..b54db39eee4c 100644
> --- a/drivers/usb/core/phy.c
> +++ b/drivers/usb/core/phy.c
> @@ -45,10 +45,11 @@ static int usb_phy_roothub_add_phy(struct device *dev, int index,
> return 0;
> }
>
> -struct usb_phy_roothub *usb_phy_roothub_alloc(struct device *dev)
> +struct usb_phy_roothub *usb_phy_roothub_alloc(struct usb_hcd *hcd)
> {
> struct usb_phy_roothub *phy_roothub;
> int i, num_phys, err;
> + struct device *dev = hcd->self.sysdev;
>
> if (!IS_ENABLED(CONFIG_GENERIC_PHY))
> return NULL;
> @@ -161,26 +162,30 @@ void usb_phy_roothub_power_off(struct usb_phy_roothub *phy_roothub)
> }
> EXPORT_SYMBOL_GPL(usb_phy_roothub_power_off);
>
> -int usb_phy_roothub_suspend(struct device *controller_dev,
> +int usb_phy_roothub_suspend(struct usb_hcd *hcd,
> struct usb_phy_roothub *phy_roothub)
> {
> + struct device *controller_dev = hcd->self.sysdev;
> +
> usb_phy_roothub_power_off(phy_roothub);
>
> /* keep the PHYs initialized so the device can wake up the system */
> - if (device_may_wakeup(controller_dev))
> + if (device_may_wakeup(controller_dev) || hcd->suspend_without_phy_exit)
> return 0;
>
> return usb_phy_roothub_exit(phy_roothub);
> }
> EXPORT_SYMBOL_GPL(usb_phy_roothub_suspend);
>
> -int usb_phy_roothub_resume(struct device *controller_dev,
> +int usb_phy_roothub_resume(struct usb_hcd *hcd,
> struct usb_phy_roothub *phy_roothub)
> {
> + struct device *controller_dev = hcd->self.sysdev;
> int err;
>
> /* if the device can't wake up the system _exit was called */
> - if (!device_may_wakeup(controller_dev)) {
> + if (!device_may_wakeup(controller_dev) &&
> + !hcd->suspend_without_phy_exit) {
> err = usb_phy_roothub_init(phy_roothub);
> if (err)
> return err;
> @@ -189,7 +194,8 @@ int usb_phy_roothub_resume(struct device *controller_dev,
> err = usb_phy_roothub_power_on(phy_roothub);
>
> /* undo _init if _power_on failed */
> - if (err && !device_may_wakeup(controller_dev))
> + if (err && !device_may_wakeup(controller_dev)
> + && !hcd->suspend_without_phy_exit)
> usb_phy_roothub_exit(phy_roothub);
>
> return err;
> diff --git a/drivers/usb/core/phy.h b/drivers/usb/core/phy.h
> index 88a3c037e9df..34293e11a917 100644
> --- a/drivers/usb/core/phy.h
> +++ b/drivers/usb/core/phy.h
> @@ -5,13 +5,16 @@
> * Copyright (C) 2018 Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx>
> */
>
> +#include <linux/usb.h>
> +#include <linux/usb/hcd.h>
> +
> #ifndef __USB_CORE_PHY_H_
> #define __USB_CORE_PHY_H_
>
> struct device;
> struct usb_phy_roothub;
>
> -struct usb_phy_roothub *usb_phy_roothub_alloc(struct device *dev);
> +struct usb_phy_roothub *usb_phy_roothub_alloc(struct usb_hcd *hcd);
>
> int usb_phy_roothub_init(struct usb_phy_roothub *phy_roothub);
> int usb_phy_roothub_exit(struct usb_phy_roothub *phy_roothub);
> @@ -19,9 +22,9 @@
> int usb_phy_roothub_power_on(struct usb_phy_roothub *phy_roothub);
> void usb_phy_roothub_power_off(struct usb_phy_roothub *phy_roothub);
>
> -int usb_phy_roothub_suspend(struct device *controller_dev,
> +int usb_phy_roothub_suspend(struct usb_hcd *hcd,
> struct usb_phy_roothub *phy_roothub);
> -int usb_phy_roothub_resume(struct device *controller_dev,
> +int usb_phy_roothub_resume(struct usb_hcd *hcd,
> struct usb_phy_roothub *phy_roothub);
>
> #endif /* __USB_CORE_PHY_H_ */
> diff --git a/include/linux/usb/hcd.h b/include/linux/usb/hcd.h
> index 97e2ddec18b1..87a104055b5e 100644
> --- a/include/linux/usb/hcd.h
> +++ b/include/linux/usb/hcd.h
> @@ -157,6 +157,9 @@ struct usb_hcd {
> */
> unsigned skip_phy_initialization:1;
>
> + /* Some phys don't want the phy's exit/init called on suspend/resume */
> + unsigned suspend_without_phy_exit:1;
As suggested before, you can skip phy's exit/init during suspend/resume
by enabling wakeup of hcd, so needn't add a new variable for it.
> +
> /* The next flag is a stopgap, to be removed when all the HCDs
> * support the new root-hub polling mechanism. */
> unsigned uses_new_polling:1;
