1 /**************************************************************************/
2 /*                                                                        */
3 /*       Copyright (c) Microsoft Corporation. All rights reserved.        */
4 /*                                                                        */
5 /*       This software is licensed under the Microsoft Software License   */
6 /*       Terms for Microsoft Azure RTOS. Full text of the license can be  */
7 /*       found in the LICENSE file at https://aka.ms/AzureRTOS_EULA       */
8 /*       and in the root directory of this software.                      */
9 /*                                                                        */
10 /**************************************************************************/
11 
12 
13 /**************************************************************************/
14 /**************************************************************************/
15 /**                                                                       */
16 /** USBX Component                                                        */
17 /**                                                                       */
18 /**   EHCI Controller Driver                                              */
19 /**                                                                       */
20 /**************************************************************************/
21 /**************************************************************************/
22 
23 
24 /* Include necessary system files.  */
25 
26 #define UX_SOURCE_CODE
27 
28 #include "ux_api.h"
29 #include "ux_hcd_ehci.h"
30 #include "ux_host_stack.h"
31 
32 
33 /**************************************************************************/
34 /*                                                                        */
35 /*  FUNCTION                                               RELEASE        */
36 /*                                                                        */
37 /*    _ux_hcd_ehci_ed_clean                               PORTABLE C      */
38 /*                                                           6.1          */
39 /*  AUTHOR                                                                */
40 /*                                                                        */
41 /*    Chaoqiong Xiao, Microsoft Corporation                               */
42 /*                                                                        */
43 /*  DESCRIPTION                                                           */
44 /*                                                                        */
45 /*    This function cleans the tds attached to a ED in case a transfer    */
46 /*    has to be aborted.                                                  */
47 /*                                                                        */
48 /*  INPUT                                                                 */
49 /*                                                                        */
50 /*    ed                                    Pointer to ED                 */
51 /*                                                                        */
52 /*  OUTPUT                                                                */
53 /*                                                                        */
54 /*    Completion Status                                                   */
55 /*                                                                        */
56 /*  CALLS                                                                 */
57 /*                                                                        */
58 /*    _ux_utility_virtual_address           Get virtual address           */
59 /*                                                                        */
60 /*  CALLED BY                                                             */
61 /*                                                                        */
62 /*    EHCI Controller Driver                                              */
63 /*                                                                        */
64 /*  RELEASE HISTORY                                                       */
65 /*                                                                        */
66 /*    DATE              NAME                      DESCRIPTION             */
67 /*                                                                        */
68 /*  05-19-2020     Chaoqiong Xiao           Initial Version 6.0           */
69 /*  09-30-2020     Chaoqiong Xiao           Modified comment(s),          */
70 /*                                            resulting in version 6.1    */
71 /*                                                                        */
72 /**************************************************************************/
_ux_hcd_ehci_ed_clean(UX_EHCI_ED * ed)73 UINT  _ux_hcd_ehci_ed_clean(UX_EHCI_ED *ed)
74 {
75 
76 UX_EHCI_TD      *td;
77 UX_EHCI_TD      *next_td;
78 
79 
80     /* Get the first pointer to the TD.  */
81     td =  ed -> ux_ehci_ed_queue_element;
82     td =  (UX_EHCI_TD *) ((ULONG) td & ~UX_EHCI_QH_T);
83     td =  _ux_utility_virtual_address(td);
84 
85     /* Mark the TD link of the endpoint as terminated.  */
86     ed -> ux_ehci_ed_queue_element =  (UX_EHCI_TD *) UX_EHCI_TD_T;
87 
88     /* Free all tds attached to the ED.  */
89     while (td != UX_NULL)
90     {
91 
92         /* Get the next TD pointed by the current TD.  */
93         next_td =  td -> ux_ehci_td_link_pointer;
94         next_td =  (UX_EHCI_TD *) ((ULONG) next_td & ~UX_EHCI_TD_T);
95         next_td =  _ux_utility_virtual_address(next_td);
96 
97         /* Mark the current TD as free.  */
98         td -> ux_ehci_td_status =  UX_UNUSED;
99 
100         td =  next_td;
101     }
102 
103     /* Reset the first TD.  */
104     ed -> ux_ehci_ed_first_td =  UX_NULL;
105 
106     /* Reset the last TD.  */
107     ed -> ux_ehci_ed_last_td =  UX_NULL;
108 
109     /* Return successful completion.  */
110     return(UX_SUCCESS);
111 }
112 
113