diff options
| -rw-r--r-- | drivers/usb/core/Makefile | 1 | ||||
| -rw-r--r-- | drivers/usb/core/driver.c | 50 | ||||
| -rw-r--r-- | drivers/usb/core/offload.c | 136 | ||||
| -rw-r--r-- | drivers/usb/core/usb.c | 1 | ||||
| -rw-r--r-- | drivers/usb/host/xhci-plat.c | 42 | ||||
| -rw-r--r-- | drivers/usb/host/xhci-plat.h | 1 | ||||
| -rw-r--r-- | drivers/usb/host/xhci-sideband.c | 36 | ||||
| -rw-r--r-- | include/linux/usb.h | 18 | ||||
| -rw-r--r-- | include/linux/usb/xhci-sideband.h | 9 |
9 files changed, 284 insertions, 10 deletions
diff --git a/drivers/usb/core/Makefile b/drivers/usb/core/Makefile index ac006abd13b3..766000b4939e 100644 --- a/drivers/usb/core/Makefile +++ b/drivers/usb/core/Makefile @@ -9,6 +9,7 @@ usbcore-y += devio.o notify.o generic.o quirks.o devices.o usbcore-y += phy.o port.o usbcore-$(CONFIG_OF) += of.o +usbcore-$(CONFIG_USB_XHCI_SIDEBAND) += offload.o usbcore-$(CONFIG_USB_PCI) += hcd-pci.o usbcore-$(CONFIG_ACPI) += usb-acpi.o diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c index 25358cf3e324..6418cfb0fb37 100644 --- a/drivers/usb/core/driver.c +++ b/drivers/usb/core/driver.c @@ -1420,11 +1420,28 @@ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg) udev->state == USB_STATE_SUSPENDED) goto done; + if (msg.event == PM_EVENT_SUSPEND && usb_offload_check(udev)) { + dev_dbg(&udev->dev, "device offloaded, skip suspend.\n"); + udev->offload_at_suspend = 1; + } + /* Suspend all the interfaces and then udev itself */ if (udev->actconfig) { n = udev->actconfig->desc.bNumInterfaces; for (i = n - 1; i >= 0; --i) { intf = udev->actconfig->interface[i]; + /* + * Don't suspend interfaces with remote wakeup while + * the controller is active. This preserves pending + * interrupt urbs, allowing interrupt events to be + * handled during system suspend. + */ + if (udev->offload_at_suspend && + intf->needs_remote_wakeup) { + dev_dbg(&intf->dev, + "device offloaded, skip suspend.\n"); + continue; + } status = usb_suspend_interface(udev, intf, msg); /* Ignore errors during system sleep transitions */ @@ -1435,7 +1452,8 @@ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg) } } if (status == 0) { - status = usb_suspend_device(udev, msg); + if (!udev->offload_at_suspend) + status = usb_suspend_device(udev, msg); /* * Ignore errors from non-root-hub devices during @@ -1480,9 +1498,11 @@ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg) */ } else { udev->can_submit = 0; - for (i = 0; i < 16; ++i) { - usb_hcd_flush_endpoint(udev, udev->ep_out[i]); - usb_hcd_flush_endpoint(udev, udev->ep_in[i]); + if (!udev->offload_at_suspend) { + for (i = 0; i < 16; ++i) { + usb_hcd_flush_endpoint(udev, udev->ep_out[i]); + usb_hcd_flush_endpoint(udev, udev->ep_in[i]); + } } } @@ -1524,17 +1544,35 @@ static int usb_resume_both(struct usb_device *udev, pm_message_t msg) udev->can_submit = 1; /* Resume the device */ - if (udev->state == USB_STATE_SUSPENDED || udev->reset_resume) - status = usb_resume_device(udev, msg); + if (udev->state == USB_STATE_SUSPENDED || udev->reset_resume) { + if (!udev->offload_at_suspend) + status = usb_resume_device(udev, msg); + else + dev_dbg(&udev->dev, + "device offloaded, skip resume.\n"); + } /* Resume the interfaces */ if (status == 0 && udev->actconfig) { for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) { intf = udev->actconfig->interface[i]; + /* + * Interfaces with remote wakeup aren't suspended + * while the controller is active. This preserves + * pending interrupt urbs, allowing interrupt events + * to be handled during system suspend. + */ + if (udev->offload_at_suspend && + intf->needs_remote_wakeup) { + dev_dbg(&intf->dev, + "device offloaded, skip resume.\n"); + continue; + } usb_resume_interface(udev, intf, msg, udev->reset_resume); } } + udev->offload_at_suspend = 0; usb_mark_last_busy(udev); done: diff --git a/drivers/usb/core/offload.c b/drivers/usb/core/offload.c new file mode 100644 index 000000000000..7c699f1b8d2b --- /dev/null +++ b/drivers/usb/core/offload.c @@ -0,0 +1,136 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * offload.c - USB offload related functions + * + * Copyright (c) 2025, Google LLC. + * + * Author: Guan-Yu Lin + */ + +#include <linux/usb.h> + +#include "usb.h" + +/** + * usb_offload_get - increment the offload_usage of a USB device + * @udev: the USB device to increment its offload_usage + * + * Incrementing the offload_usage of a usb_device indicates that offload is + * enabled on this usb_device; that is, another entity is actively handling USB + * transfers. This information allows the USB driver to adjust its power + * management policy based on offload activity. + * + * Return: 0 on success. A negative error code otherwise. + */ +int usb_offload_get(struct usb_device *udev) +{ + int ret; + + usb_lock_device(udev); + if (udev->state == USB_STATE_NOTATTACHED) { + usb_unlock_device(udev); + return -ENODEV; + } + + if (udev->state == USB_STATE_SUSPENDED || + udev->offload_at_suspend) { + usb_unlock_device(udev); + return -EBUSY; + } + + /* + * offload_usage could only be modified when the device is active, since + * it will alter the suspend flow of the device. + */ + ret = usb_autoresume_device(udev); + if (ret < 0) { + usb_unlock_device(udev); + return ret; + } + + udev->offload_usage++; + usb_autosuspend_device(udev); + usb_unlock_device(udev); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_offload_get); + +/** + * usb_offload_put - drop the offload_usage of a USB device + * @udev: the USB device to drop its offload_usage + * + * The inverse operation of usb_offload_get, which drops the offload_usage of + * a USB device. This information allows the USB driver to adjust its power + * management policy based on offload activity. + * + * Return: 0 on success. A negative error code otherwise. + */ +int usb_offload_put(struct usb_device *udev) +{ + int ret; + + usb_lock_device(udev); + if (udev->state == USB_STATE_NOTATTACHED) { + usb_unlock_device(udev); + return -ENODEV; + } + + if (udev->state == USB_STATE_SUSPENDED || + udev->offload_at_suspend) { + usb_unlock_device(udev); + return -EBUSY; + } + + /* + * offload_usage could only be modified when the device is active, since + * it will alter the suspend flow of the device. + */ + ret = usb_autoresume_device(udev); + if (ret < 0) { + usb_unlock_device(udev); + return ret; + } + + /* Drop the count when it wasn't 0, ignore the operation otherwise. */ + if (udev->offload_usage) + udev->offload_usage--; + usb_autosuspend_device(udev); + usb_unlock_device(udev); + + return ret; +} +EXPORT_SYMBOL_GPL(usb_offload_put); + +/** + * usb_offload_check - check offload activities on a USB device + * @udev: the USB device to check its offload activity. + * + * Check if there are any offload activity on the USB device right now. This + * information could be used for power management or other forms of resource + * management. + * + * The caller must hold @udev's device lock. In addition, the caller should + * ensure downstream usb devices are all either suspended or marked as + * "offload_at_suspend" to ensure the correctness of the return value. + * + * Returns true on any offload activity, false otherwise. + */ +bool usb_offload_check(struct usb_device *udev) __must_hold(&udev->dev->mutex) +{ + struct usb_device *child; + bool active; + int port1; + + usb_hub_for_each_child(udev, port1, child) { + usb_lock_device(child); + active = usb_offload_check(child); + usb_unlock_device(child); + if (active) + return true; + } + + return !!udev->offload_usage; +} +EXPORT_SYMBOL_GPL(usb_offload_check); diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c index b88b6271cb30..b6b0b8489523 100644 --- a/drivers/usb/core/usb.c +++ b/drivers/usb/core/usb.c @@ -670,6 +670,7 @@ struct usb_device *usb_alloc_dev(struct usb_device *parent, set_dev_node(&dev->dev, dev_to_node(bus->sysdev)); dev->state = USB_STATE_ATTACHED; dev->lpm_disable_count = 1; + dev->offload_usage = 0; atomic_set(&dev->urbnum, 0); INIT_LIST_HEAD(&dev->ep0.urb_list); diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c index 5eb51797de32..3a56d8f94519 100644 --- a/drivers/usb/host/xhci-plat.c +++ b/drivers/usb/host/xhci-plat.c @@ -20,6 +20,7 @@ #include <linux/acpi.h> #include <linux/usb/of.h> #include <linux/reset.h> +#include <linux/usb/xhci-sideband.h> #include "xhci.h" #include "xhci-plat.h" @@ -454,7 +455,7 @@ void xhci_plat_remove(struct platform_device *dev) } EXPORT_SYMBOL_GPL(xhci_plat_remove); -static int xhci_plat_suspend(struct device *dev) +static int xhci_plat_suspend_common(struct device *dev) { struct usb_hcd *hcd = dev_get_drvdata(dev); struct xhci_hcd *xhci = hcd_to_xhci(hcd); @@ -482,6 +483,25 @@ static int xhci_plat_suspend(struct device *dev) return 0; } +static int xhci_plat_suspend(struct device *dev) +{ + struct usb_hcd *hcd = dev_get_drvdata(dev); + struct xhci_plat_priv *priv = hcd_to_xhci_priv(hcd); + + if (xhci_sideband_check(hcd)) { + priv->sideband_at_suspend = 1; + dev_dbg(dev, "sideband instance active, skip suspend.\n"); + return 0; + } + + return xhci_plat_suspend_common(dev); +} + +static int xhci_plat_freeze(struct device *dev) +{ + return xhci_plat_suspend_common(dev); +} + static int xhci_plat_resume_common(struct device *dev, bool power_lost) { struct usb_hcd *hcd = dev_get_drvdata(dev); @@ -526,6 +546,20 @@ disable_clks: static int xhci_plat_resume(struct device *dev) { + struct usb_hcd *hcd = dev_get_drvdata(dev); + struct xhci_plat_priv *priv = hcd_to_xhci_priv(hcd); + + if (priv->sideband_at_suspend) { + priv->sideband_at_suspend = 0; + dev_dbg(dev, "sideband instance active, skip resume.\n"); + return 0; + } + + return xhci_plat_resume_common(dev, false); +} + +static int xhci_plat_thaw(struct device *dev) +{ return xhci_plat_resume_common(dev, false); } @@ -558,9 +592,9 @@ static int __maybe_unused xhci_plat_runtime_resume(struct device *dev) const struct dev_pm_ops xhci_plat_pm_ops = { .suspend = pm_sleep_ptr(xhci_plat_suspend), .resume = pm_sleep_ptr(xhci_plat_resume), - .freeze = pm_sleep_ptr(xhci_plat_suspend), - .thaw = pm_sleep_ptr(xhci_plat_resume), - .poweroff = pm_sleep_ptr(xhci_plat_suspend), + .freeze = pm_sleep_ptr(xhci_plat_freeze), + .thaw = pm_sleep_ptr(xhci_plat_thaw), + .poweroff = pm_sleep_ptr(xhci_plat_freeze), .restore = pm_sleep_ptr(xhci_plat_restore), SET_RUNTIME_PM_OPS(xhci_plat_runtime_suspend, diff --git a/drivers/usb/host/xhci-plat.h b/drivers/usb/host/xhci-plat.h index fe4f95e690fa..2b32a93d2b76 100644 --- a/drivers/usb/host/xhci-plat.h +++ b/drivers/usb/host/xhci-plat.h @@ -16,6 +16,7 @@ struct xhci_plat_priv { const char *firmware_name; unsigned long long quirks; bool power_lost; + unsigned sideband_at_suspend:1; void (*plat_start)(struct usb_hcd *); int (*init_quirk)(struct usb_hcd *); int (*suspend_quirk)(struct usb_hcd *); diff --git a/drivers/usb/host/xhci-sideband.c b/drivers/usb/host/xhci-sideband.c index d49f9886dd84..e771a476fef2 100644 --- a/drivers/usb/host/xhci-sideband.c +++ b/drivers/usb/host/xhci-sideband.c @@ -267,6 +267,31 @@ xhci_sideband_get_event_buffer(struct xhci_sideband *sb) EXPORT_SYMBOL_GPL(xhci_sideband_get_event_buffer); /** + * xhci_sideband_check - check the existence of active sidebands + * @hcd: the host controller driver associated with the target host controller + * + * Allow other drivers, such as usb controller driver, to check if there are + * any sideband activity on the host controller. This information could be used + * for power management or other forms of resource management. The caller should + * ensure downstream usb devices are all either suspended or marked as + * "offload_at_suspend" to ensure the correctness of the return value. + * + * Returns true on any active sideband existence, false otherwise. + */ +bool xhci_sideband_check(struct usb_hcd *hcd) +{ + struct usb_device *udev = hcd->self.root_hub; + bool active; + + usb_lock_device(udev); + active = usb_offload_check(udev); + usb_unlock_device(udev); + + return active; +} +EXPORT_SYMBOL_GPL(xhci_sideband_check); + +/** * xhci_sideband_create_interrupter - creates a new interrupter for this sideband * @sb: sideband instance for this usb device * @num_seg: number of event ring segments to allocate @@ -286,6 +311,7 @@ xhci_sideband_create_interrupter(struct xhci_sideband *sb, int num_seg, bool ip_autoclear, u32 imod_interval, int intr_num) { int ret = 0; + struct usb_device *udev; if (!sb || !sb->xhci) return -ENODEV; @@ -304,6 +330,9 @@ xhci_sideband_create_interrupter(struct xhci_sideband *sb, int num_seg, goto out; } + udev = sb->vdev->udev; + ret = usb_offload_get(udev); + sb->ir->ip_autoclear = ip_autoclear; out: @@ -323,6 +352,8 @@ EXPORT_SYMBOL_GPL(xhci_sideband_create_interrupter); void xhci_sideband_remove_interrupter(struct xhci_sideband *sb) { + struct usb_device *udev; + if (!sb || !sb->ir) return; @@ -330,6 +361,11 @@ xhci_sideband_remove_interrupter(struct xhci_sideband *sb) xhci_remove_secondary_interrupter(xhci_to_hcd(sb->xhci), sb->ir); sb->ir = NULL; + udev = sb->vdev->udev; + + if (udev->state != USB_STATE_NOTATTACHED) + usb_offload_put(udev); + mutex_unlock(&sb->mutex); } EXPORT_SYMBOL_GPL(xhci_sideband_remove_interrupter); diff --git a/include/linux/usb.h b/include/linux/usb.h index 70ef00c42d22..e85105939af8 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -636,6 +636,8 @@ struct usb3_lpm_parameters { * @do_remote_wakeup: remote wakeup should be enabled * @reset_resume: needs reset instead of resume * @port_is_suspended: the upstream port is suspended (L2 or U3) + * @offload_at_suspend: offload activities during suspend is enabled. + * @offload_usage: number of offload activities happening on this usb device. * @slot_id: Slot ID assigned by xHCI * @l1_params: best effor service latency for USB2 L1 LPM state, and L1 timeout. * @u1_params: exit latencies for USB3 U1 LPM state, and hub-initiated timeout. @@ -724,6 +726,8 @@ struct usb_device { unsigned do_remote_wakeup:1; unsigned reset_resume:1; unsigned port_is_suspended:1; + unsigned offload_at_suspend:1; + int offload_usage; enum usb_link_tunnel_mode tunnel_mode; struct device_link *usb4_link; @@ -841,6 +845,20 @@ static inline void usb_mark_last_busy(struct usb_device *udev) { } #endif +#if IS_ENABLED(CONFIG_USB_XHCI_SIDEBAND) +int usb_offload_get(struct usb_device *udev); +int usb_offload_put(struct usb_device *udev); +bool usb_offload_check(struct usb_device *udev); +#else + +static inline int usb_offload_get(struct usb_device *udev) +{ return 0; } +static inline int usb_offload_put(struct usb_device *udev) +{ return 0; } +static inline bool usb_offload_check(struct usb_device *udev) +{ return false; } +#endif + extern int usb_disable_lpm(struct usb_device *udev); extern void usb_enable_lpm(struct usb_device *udev); /* Same as above, but these functions lock/unlock the bandwidth_mutex. */ diff --git a/include/linux/usb/xhci-sideband.h b/include/linux/usb/xhci-sideband.h index 45288c392f6e..005257085dcb 100644 --- a/include/linux/usb/xhci-sideband.h +++ b/include/linux/usb/xhci-sideband.h @@ -11,6 +11,7 @@ #include <linux/scatterlist.h> #include <linux/usb.h> +#include <linux/usb/hcd.h> #define EP_CTX_PER_DEV 31 /* FIXME defined twice, from xhci.h */ @@ -83,6 +84,14 @@ xhci_sideband_get_endpoint_buffer(struct xhci_sideband *sb, struct usb_host_endpoint *host_ep); struct sg_table * xhci_sideband_get_event_buffer(struct xhci_sideband *sb); + +#if IS_ENABLED(CONFIG_USB_XHCI_SIDEBAND) +bool xhci_sideband_check(struct usb_hcd *hcd); +#else +static inline bool xhci_sideband_check(struct usb_hcd *hcd) +{ return false; } +#endif /* IS_ENABLED(CONFIG_USB_XHCI_SIDEBAND) */ + int xhci_sideband_create_interrupter(struct xhci_sideband *sb, int num_seg, bool ip_autoclear, u32 imod_interval, int intr_num); |