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| author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-09-12 14:08:09 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-09-12 14:08:09 +0200 |
| commit | 44bbcba50d55ca97e09b0eaa7c1e6bf97b9f425d (patch) | |
| tree | 48bfe0425fac7820beeb70cd2fdc40b1483db2b6 /include/linux/usb | |
| parent | daf161343a3904f6699febbfb1e18d532371ba00 (diff) | |
| parent | 38d627bc8522a6a2fd6f9454c8b3b5d3848f5f03 (diff) | |
Merge patch series "Support system sleep with offloaded usb transfers" into usb-next
Guan-Yu Lin <guanyulin@google.com> says:
Wesley Cheng and Mathias Nyman's USB offload design enables a
co-processor to handle some USB transfers, potentially allowing the
system to sleep (suspend-to-RAM) and save power. However, Linux's System
Sleep model halts the USB host controller when the main system isn't
managing any USB transfers. To address this, the proposal modifies the
system to recognize offloaded USB transfers and manage power
accordingly. This way, offloaded USB transfers could still happen during
system sleep (Suspend-to-RAM).
This involves two key steps:
1. Transfer Status Tracking: Propose offload_usage and corresponding
apis drivers could track USB transfers on the co-processor, ensuring
the system is aware of any ongoing activity.
2. Power Management Adjustment: Modifications to the USB driver stack
(xhci host controller driver, and USB device drivers) allow the
system to sleep (Suspend-to-RAM) without disrupting co-processor
managed USB transfers. This involves adding conditional checks to
bypass some power management operations in the System Sleep model.
Link: https://lore.kernel.org/r/20250911142051.90822-1-guanyulin@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/linux/usb')
| -rw-r--r-- | include/linux/usb/xhci-sideband.h | 9 |
1 files changed, 9 insertions, 0 deletions
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); |