Commit 82beac34 authored by Wesley Cheng's avatar Wesley Cheng Committed by Elson Roy Serrao
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BACKPORT: UPSTREAM: usb: dwc3: EP clear halt leading to clearing of delayed_status



The usb_ep_clear_halt() API can be called from the function driver, and
translates to dwc3_gadget_ep_set_halt().  This routine is shared with when
the host issues a clear feature ENDPOINT_HALT, and is differentiated by the
protocol argument.  If the following sequence occurs, there can be a
situation where the delayed_status flag is improperly cleared for the wrong
SETUP transaction:

1. Vendor specific control transfer returns USB_GADGET_DELAYED_STATUS.
2. DWC3 gadget sets dwc->delayed_status to '1'.
3. Another function driver issues a usb_ep_clear_halt() call.
4. DWC3 gadget issues dwc3_stop_active_transfer() and sets
   DWC3_EP_PENDING_CLEAR_STALL.
5. EP command complete interrupt triggers for the end transfer, and
   dwc3_ep0_send_delayed_status() is allowed to run, as delayed_status
   is '1' due to step#1.
6. STATUS phase is sent, and delayed_status is cleared.
7. Vendor specific control transfer is finished being handled, and issues
   usb_composite_setup_continue().  This results in queuing of a data
   phase.

Cache the protocol flag so that DWC3 gadget is aware of when the clear halt
is due to a SETUP request from the host versus when it is sourced from a
function driver.  This allows for the EP command complete interrupt to know
if it needs to issue a delayed status phase.

type 'struct dwc3' changed
  member 'union { struct { u8 clear_stall_protocol; u8 padding1;
  u8 padding2; u8 padding3; u8 padding4; u8 padding5; u8 padding6;
  u8 padding7; }; struct { u64 android_kabi_reserved1; };
  union { }; }' was added.
  member 'u64 android_kabi_reserved1' was removed.

Signed-off-by: default avatarWesley Cheng <quic_wcheng@quicinc.com>
Link: https://lore.kernel.org/r/20220414073902.21960-1-quic_wcheng@quicinc.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>

(cherry picked from commit 2840d6df)

BUG: 263499807
[eserrao: Fixed KMI breakage by moving clear_stall_protocol to a new
parent structure]
Change-Id: I46bc6b0246218c60e36f2b6ce45dc9c156cee4f0
Signed-off-by: default avatarElson Roy Serrao <quic_eserrao@quicinc.com>
parent 016d6109
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