The previous patch on the endpoint reset uses the already implemented function
xhci_drop_endpoint() to reduce code duplication. However, the way that xhci
updates the last valid endpoint in the Input Slot Context, when an endpoint
is dropped, can lead to incosistent value for the last valid endpoint.
That can happen when the endpoint to be reset has index smaller than the
current last valid endpoint. In that case the last valid endpoint will end up
being updated with a smaller value and if there are valid endpoints with index
higher than the index of the reset endpoint, the xHC will consider them as
invalid and the transactions to these endpoints will break.
This patch updates the last valid endpoint with the index of the first not
disabled endpoint, starting from the current last valid endpoint and skipping
the dropped endpoint.
Signed-off-by: Xenia Ragiadakou <burzalodowa@xxxxxxxxx>
---
drivers/usb/host/xhci.c | 22 +++++++++++++++-------
1 file changed, 15 insertions(+), 7 deletions(-)
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index e6300b5..97670f5 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -1547,7 +1547,7 @@ int xhci_drop_endpoint(struct usb_hcd *hcd, struct usb_device *udev,
struct xhci_container_ctx *in_ctx, *out_ctx;
struct xhci_input_control_ctx *ctrl_ctx;
struct xhci_slot_ctx *slot_ctx;
- unsigned int last_ctx;
+ unsigned int last_ep_index;
unsigned int ep_index;
struct xhci_ep_ctx *ep_ctx;
u32 drop_flag;
@@ -1598,13 +1598,21 @@ int xhci_drop_endpoint(struct usb_hcd *hcd, struct usb_device *udev,
ctrl_ctx->add_flags &= cpu_to_le32(~drop_flag);
new_add_flags = le32_to_cpu(ctrl_ctx->add_flags);
- last_ctx = xhci_last_valid_endpoint(le32_to_cpu(ctrl_ctx->add_flags));
+ slot_ctx = xhci_get_slot_ctx(xhci, out_ctx);
+ last_ep_index = LAST_CTX_TO_EP_NUM(le32_to_cpu(slot_ctx->dev_info));
slot_ctx = xhci_get_slot_ctx(xhci, in_ctx);
- /* Update the last valid endpoint context, if we deleted the last one */
- if ((le32_to_cpu(slot_ctx->dev_info) & LAST_CTX_MASK) >
- LAST_CTX(last_ctx)) {
- slot_ctx->dev_info &= cpu_to_le32(~LAST_CTX_MASK);
- slot_ctx->dev_info |= cpu_to_le32(LAST_CTX(last_ctx));
+ for (; last_ep_index >= 0; --last_ep_index) {
+ /* skip the dropped endpoint's index */
+ if (last_ep_index == ep_index)
+ continue;
+ ep_ctx = xhci_get_ep_ctx(xhci, out_ctx, last_ep_index);
+ if ((ep_ctx->ep_info & cpu_to_le32(EP_STATE_MASK)) !=
+ cpu_to_le32(EP_STATE_DISABLED)) {
+ slot_ctx->dev_info &= cpu_to_le32(~LAST_CTX_MASK);
+ slot_ctx->dev_info |=
+ cpu_to_le32(LAST_CTX(last_ep_index + 1));
+ break;
+ }
}
new_slot_info = le32_to_cpu(slot_ctx->dev_info);
--
1.8.3.4
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