From 574aabfd5a408bc10da01bb4abe222abc013ea45 Mon Sep 17 00:00:00 2001
From: Jonathan Bell <jonathan@raspberrypi.org>
Date: Tue, 11 Jun 2019 11:33:39 +0100
Subject: [PATCH] xhci: implement xhci_fixup_endpoint for interval
adjustments
Must be called in a non-atomic context, after the endpoint
has been registered with the hardware via xhci_add_endpoint
and before the first URB is submitted for the endpoint.
Signed-off-by: Jonathan Bell <jonathan@raspberrypi.org>
---
drivers/usb/host/xhci.c | 98 +++++++++++++++++++++++++++++++++++++++++
1 file changed, 98 insertions(+)
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -1485,6 +1485,103 @@ command_cleanup:
}
/*
+ * RPI: Fixup endpoint intervals when requested
+ * - Check interval versus the (cached) endpoint context
+ * - set the endpoint interval to the new value
+ * - force an endpoint configure command
+ * XXX: bandwidth is not recalculated. We should probably do that.
+ */
+static void xhci_fixup_endpoint(struct usb_hcd *hcd, struct usb_device *udev,
+ struct usb_host_endpoint *ep, int interval)
+{
+ struct xhci_hcd *xhci;
+ struct xhci_ep_ctx *ep_ctx_out, *ep_ctx_in;
+ struct xhci_command *command;
+ struct xhci_input_control_ctx *ctrl_ctx;
+ struct xhci_virt_device *vdev;
+ int xhci_interval;
+ int ret;
+ int ep_index;
+ unsigned long flags;
+ u32 ep_info_tmp;
+
+ xhci = hcd_to_xhci(hcd);
+ ep_index = xhci_get_endpoint_index(&ep->desc);
+
+ /* FS/LS interval translations */
+ if ((udev->speed == USB_SPEED_FULL ||
+ udev->speed == USB_SPEED_LOW))
+ interval *= 8;
+
+ mutex_lock(&xhci->mutex);
+
+ spin_lock_irqsave(&xhci->lock, flags);
+
+ vdev = xhci->devs[udev->slot_id];
+ /* Get context-derived endpoint interval */
+ ep_ctx_out = xhci_get_ep_ctx(xhci, vdev->out_ctx, ep_index);
+ ep_ctx_in = xhci_get_ep_ctx(xhci, vdev->in_ctx, ep_index);
+ xhci_interval = EP_INTERVAL_TO_UFRAMES(le32_to_cpu(ep_ctx_out->ep_info));
+
+ if (interval == xhci_interval) {
+ spin_unlock_irqrestore(&xhci->lock, flags);
+ mutex_unlock(&xhci->mutex);
+ return;
+ }
+
+ xhci_dbg(xhci, "Fixup interval=%d xhci_interval=%d\n",
+ interval, xhci_interval);
+ command = xhci_alloc_command_with_ctx(xhci, true, GFP_ATOMIC);
+ if (!command) {
+ /* Failure here is benign, poll at the original rate */
+ spin_unlock_irqrestore(&xhci->lock, flags);
+ mutex_unlock(&xhci->mutex);
+ return;
+ }
+
+ /* xHCI uses exponents for intervals... */
+ xhci_interval = fls(interval) - 1;
+ xhci_interval = clamp_val(xhci_interval, 3, 10);
+ ep_info_tmp = le32_to_cpu(ep_ctx_out->ep_info);
+ ep_info_tmp &= ~EP_INTERVAL(255);
+ ep_info_tmp |= EP_INTERVAL(xhci_interval);
+
+ /* Keep the endpoint context up-to-date while issuing the command. */
+ xhci_endpoint_copy(xhci, vdev->in_ctx,
+ vdev->out_ctx, ep_index);
+ ep_ctx_in->ep_info = cpu_to_le32(ep_info_tmp);
+
+ /*
+ * We need to drop the lock, so take an explicit copy
+ * of the ep context.
+ */
+ xhci_endpoint_copy(xhci, command->in_ctx, vdev->in_ctx, ep_index);
+
+ ctrl_ctx = xhci_get_input_control_ctx(command->in_ctx);
+ if (!ctrl_ctx) {
+ xhci_warn(xhci,
+ "%s: Could not get input context, bad type.\n",
+ __func__);
+ spin_unlock_irqrestore(&xhci->lock, flags);
+ xhci_free_command(xhci, command);
+ mutex_unlock(&xhci->mutex);
+ return;
+ }
+ ctrl_ctx->add_flags = xhci_get_endpoint_flag_from_index(ep_index);
+ ctrl_ctx->drop_flags = 0;
+
+ spin_unlock_irqrestore(&xhci->lock, flags);
+
+ ret = xhci_configure_endpoint(xhci, udev, command,
+ false, false);
+ if (ret)
+ xhci_warn(xhci, "%s: Configure endpoint failed: %d\n",
+ __func__, ret);
+ xhci_free_command(xhci, command);
+ mutex_unlock(&xhci->mutex);
+}
+
+/*
* non-error returns are a promise to giveback() the urb later
* we drop ownership so next owner (or urb unlink) can get it
*/
@@ -5391,6 +5488,7 @@ static const struct hc_driver xhci_hc_dr
.endpoint_reset = xhci_endpoint_reset,
.check_bandwidth = xhci_check_bandwidth,
.reset_bandwidth = xhci_reset_bandwidth,
+ .fixup_endpoint = xhci_fixup_endpoint,
.address_device = xhci_address_device,
.enable_device = xhci_enable_device,
.update_hub_device = xhci_update_hub_device,