1 /*
2  * Copyright (c) 2021-2022 Huawei Device Co., Ltd.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at
6  *
7  *     http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 
16 #ifndef HDF_USB_DATA_FIFO_H
17 #define HDF_USB_DATA_FIFO_H
18 
19 #include "hdf_base.h"
20 #include "hdf_log.h"
21 
22 #ifndef MIN
23 #define MIN(a, b) ((a) < (b) ? (a) : (b))
24 #endif
25 
26 #ifndef MAX
27 #define MAX(a, b) ((a) > (b) ? (a) : (b))
28 #endif
29 
30 struct DataFifo {
31     uint32_t rdIdx;
32     uint32_t wrIdx;
33     uint32_t size;
34     void     *data;
35 };
36 
37 /* DataFifo Helper function */
DataFifoInit(struct DataFifo * fifo,uint32_t size,void * data)38 static inline void DataFifoInit(struct DataFifo *fifo, uint32_t size, void *data)
39 {
40     if (size == 0) {
41         HDF_LOGE("%{public}s: Fifo size is zero", __func__);
42         return;
43     }
44     fifo->rdIdx = 0;
45     fifo->wrIdx = 0;
46     fifo->size = size;
47     fifo->data = data;
48 }
49 
DataFifoIsInitialized(struct DataFifo * fifo)50 static inline bool DataFifoIsInitialized(struct DataFifo *fifo)
51 {
52     return fifo->size != 0;
53 }
54 
DataFifoReset(struct DataFifo * fifo)55 static inline void DataFifoReset(struct DataFifo *fifo)
56 {
57     fifo->rdIdx = fifo->wrIdx = 0;
58 }
59 
DataFifoLen(struct DataFifo * fifo)60 static inline uint32_t DataFifoLen(struct DataFifo *fifo)
61 {
62     return fifo->wrIdx - fifo->rdIdx;
63 }
64 
DataFifoIsEmpty(struct DataFifo * fifo)65 static inline bool DataFifoIsEmpty(struct DataFifo *fifo)
66 {
67     return fifo->wrIdx == fifo->rdIdx;
68 }
69 
DataFifoIsFull(struct DataFifo * fifo)70 static inline bool DataFifoIsFull(struct DataFifo *fifo)
71 {
72     return DataFifoLen(fifo) > (fifo->size - 1);
73 }
74 
DataFifoAvailSize(struct DataFifo * fifo)75 static inline uint32_t DataFifoAvailSize(struct DataFifo *fifo)
76 {
77     return fifo->size - DataFifoLen(fifo);
78 }
79 
DataFifoSkip(struct DataFifo * fifo,uint32_t size)80 static inline void DataFifoSkip(struct DataFifo *fifo, uint32_t size)
81 {
82     fifo->rdIdx += size;
83 }
84 
DataFifoWrite(struct DataFifo * fifo,uint8_t * data,uint32_t size)85 static inline uint32_t DataFifoWrite(struct DataFifo *fifo, uint8_t *data, uint32_t size)
86 {
87     uint32_t mask = fifo->size - 1;
88     uint8_t *buf = (uint8_t *)fifo->data;
89     uint8_t *end;
90 
91     size = MIN(size, DataFifoAvailSize(fifo));
92     end = data + size;
93     while (data < end) {
94         buf[fifo->wrIdx++ & mask] = *data++;
95     }
96     return size;
97 }
98 
DataFifoRead(struct DataFifo * fifo,uint8_t * data,uint32_t size)99 static inline uint32_t DataFifoRead(struct DataFifo *fifo, uint8_t *data, uint32_t size)
100 {
101     uint32_t mask = fifo->size - 1;
102     uint8_t *buf = (uint8_t *)fifo->data;
103     uint8_t *end;
104 
105     size = MIN(size, DataFifoLen(fifo));
106     end = data + size;
107     while (data < end) {
108         *data++ = buf[fifo->rdIdx++ & mask];
109     }
110     return size;
111 }
112 
113 #endif /* HDF_USB_DATA_FIFO_H */
114