@@ -1580,6 +1580,136 @@ static int xhci_check_args(struct usb_hcd *hcd, struct usb_device *udev,
return 1;
}
+int xhci_stop_endpoint(struct usb_device *udev,
+ struct usb_host_endpoint *ep)
+{
+ struct usb_hcd *hcd = bus_to_hcd(udev->bus);
+ struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+ unsigned int ep_index;
+ struct xhci_virt_device *virt_dev;
+ struct xhci_command *cmd;
+ unsigned long flags;
+ int ret = 0;
+
+ ret = xhci_check_args(hcd, udev, ep, 1, true, __func__);
+ if (ret <= 0)
+ return ret;
+
+ cmd = xhci_alloc_command(xhci, true, GFP_NOIO);
+ if (!cmd)
+ return -ENOMEM;
+
+ spin_lock_irqsave(&xhci->lock, flags);
+ virt_dev = xhci->devs[udev->slot_id];
+ if (!virt_dev) {
+ ret = -ENODEV;
+ goto err;
+ }
+
+ ep_index = xhci_get_endpoint_index(&ep->desc);
+ if (virt_dev->eps[ep_index].ring &&
+ virt_dev->eps[ep_index].ring->dequeue) {
+ ret = xhci_queue_stop_endpoint(xhci, cmd, udev->slot_id,
+ ep_index, 0);
+ if (ret)
+ goto err;
+
+ xhci_ring_cmd_db(xhci);
+ spin_unlock_irqrestore(&xhci->lock, flags);
+
+ /* Wait for stop endpoint command to finish */
+ wait_for_completion(cmd->completion);
+
+ if (cmd->status == COMP_COMMAND_ABORTED ||
+ cmd->status == COMP_STOPPED) {
+ xhci_warn(xhci,
+ "stop endpoint command timeout for ep%d%s\n",
+ usb_endpoint_num(&ep->desc),
+ usb_endpoint_dir_in(&ep->desc) ? "in" : "out");
+ ret = -ETIME;
+ }
+ goto free_cmd;
+ }
+
+err:
+ spin_unlock_irqrestore(&xhci->lock, flags);
+free_cmd:
+ xhci_free_command(xhci, cmd);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(xhci_stop_endpoint);
+
+/* Retrieve the transfer ring base address for a specific endpoint. */
+phys_addr_t xhci_get_xfer_resource(struct usb_device *udev,
+ struct usb_host_endpoint *ep, dma_addr_t *dma)
+{
+ struct usb_hcd *hcd = bus_to_hcd(udev->bus);
+ struct device *dev = hcd->self.sysdev;
+ struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+ struct sg_table sgt;
+ phys_addr_t pa;
+ int ret;
+ unsigned int ep_index;
+ struct xhci_virt_device *virt_dev;
+ unsigned long flags;
+
+ if (!HCD_RH_RUNNING(hcd))
+ return 0;
+
+ ret = xhci_check_args(hcd, udev, ep, 1, true, __func__);
+ if (ret <= 0) {
+ xhci_err(xhci, "%s: invalid args\n", __func__);
+ return 0;
+ }
+
+ spin_lock_irqsave(&xhci->lock, flags);
+
+ virt_dev = xhci->devs[udev->slot_id];
+ ep_index = xhci_get_endpoint_index(&ep->desc);
+
+ if (virt_dev->eps[ep_index].ring &&
+ virt_dev->eps[ep_index].ring->first_seg) {
+
+ dma_get_sgtable(dev, &sgt,
+ virt_dev->eps[ep_index].ring->first_seg->trbs,
+ virt_dev->eps[ep_index].ring->first_seg->dma,
+ TRB_SEGMENT_SIZE);
+
+ *dma = virt_dev->eps[ep_index].ring->first_seg->dma;
+
+ pa = page_to_phys(sg_page(sgt.sgl));
+ sg_free_table(&sgt);
+ spin_unlock_irqrestore(&xhci->lock, flags);
+
+ return pa;
+ }
+ spin_unlock_irqrestore(&xhci->lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(xhci_get_xfer_resource);
+
+phys_addr_t xhci_get_ir_resource(struct usb_device *udev, struct xhci_interrupter *ir)
+{
+ struct usb_hcd *hcd = bus_to_hcd(udev->bus);
+ struct device *dev = hcd->self.sysdev;
+ struct sg_table sgt;
+ phys_addr_t pa;
+
+ if (!ir)
+ return 0;
+
+ dma_get_sgtable(dev, &sgt, ir->event_ring->first_seg->trbs,
+ ir->event_ring->first_seg->dma, TRB_SEGMENT_SIZE);
+
+ pa = page_to_phys(sg_page(sgt.sgl));
+ sg_free_table(&sgt);
+
+ return pa;
+}
+EXPORT_SYMBOL_GPL(xhci_get_ir_resource);
+
static int xhci_configure_endpoint(struct xhci_hcd *xhci,
struct usb_device *udev, struct xhci_command *command,
bool ctx_change, bool must_succeed);
@@ -80,7 +80,15 @@ struct xhci_interrupter {
u64 s3_erst_dequeue;
};
+/* Secondary interrupter */
struct xhci_interrupter *
xhci_create_secondary_interrupter(struct usb_hcd *hcd, int intr_num);
void xhci_remove_secondary_interrupter(struct usb_hcd *hcd, struct xhci_interrupter *ir);
+
+/* Offload */
+int xhci_stop_endpoint(struct usb_device *udev,
+ struct usb_host_endpoint *ep);
+phys_addr_t xhci_get_xfer_resource(struct usb_device *udev,
+ struct usb_host_endpoint *ep, dma_addr_t *dma);
+phys_addr_t xhci_get_ir_resource(struct usb_device *udev, struct xhci_interrupter *ir);
#endif
Some use cases, such as USB audio offloading, will allow for a DSP to take over issuing USB transfers to the host controller. In order for the DSP to submit transfers for a particular endpoint, and to handle its events, the client driver will need to query for some parameters allocated by XHCI. - XHCI secondary interrupter event ring address - XHCI transfer ring address (for a particular EP) - Stop endpoint command API Once the resources are handed off to the DSP, the offload begins, and the main processor can enter idle. When stopped, since there are no URBs submitted from the main processor, the client will just issue a stop endpoint command to halt any pending transfers. Signed-off-by: Wesley Cheng <quic_wcheng@quicinc.com> --- drivers/usb/host/xhci.c | 130 ++++++++++++++++++++++++++++++++++ include/linux/usb/xhci-intr.h | 8 +++ 2 files changed, 138 insertions(+)