1 /*
2  * Copyright (C) 2011 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #define LOG_TAG "local_time_hw_default"
18 //#define LOG_NDEBUG 0
19 
20 #include <errno.h>
21 #include <malloc.h>
22 #include <stdint.h>
23 #include <string.h>
24 #include <time.h>
25 
26 #include <log/log.h>
27 
28 #include <hardware/hardware.h>
29 #include <hardware/local_time_hal.h>
30 
31 // We only support gcc and clang, both of which support this attribute.
32 #define UNUSED_ARGUMENT __attribute((unused))
33 
34 struct stub_local_time_device {
35     struct local_time_hw_device device;
36 };
37 
38 static int64_t ltdev_get_local_time(struct local_time_hw_device* dev)
39 {
40     struct timespec ts;
41     uint64_t now;
42     int ret;
43 
44     ret = clock_gettime(CLOCK_MONOTONIC, &ts);
45     if (ret < 0) {
46         ALOGW("%s failed to fetch CLOCK_MONOTONIC value! (res = %d)",
47                 dev->common.module->name, ret);
48         return 0;
49     }
50 
51     now = (((uint64_t)ts.tv_sec) * 1000000000ull) +
52            ((uint64_t)ts.tv_nsec);
53 
54     return (int64_t)now;
55 }
56 
57 static uint64_t ltdev_get_local_freq(
58         struct local_time_hw_device* dev UNUSED_ARGUMENT)
59 {
60     // For better or worse, linux clock_gettime routines normalize all clock
61     // frequencies to 1GHz
62     return 1000000000ull;
63 }
64 
65 static int ltdev_close(hw_device_t *device)
66 {
67     free(device);
68     return 0;
69 }
70 
71 static int ltdev_open(const hw_module_t* module, const char* name,
72                      hw_device_t** device)
73 {
74     struct stub_local_time_device *ltdev;
75 
76     if (strcmp(name, LOCAL_TIME_HARDWARE_INTERFACE) != 0)
77         return -EINVAL;
78 
79     ltdev = calloc(1, sizeof(struct stub_local_time_device));
80     if (!ltdev)
81         return -ENOMEM;
82 
83     ltdev->device.common.tag = HARDWARE_DEVICE_TAG;
84     ltdev->device.common.version = 0;
85     ltdev->device.common.module = (struct hw_module_t *) module;
86     ltdev->device.common.close = ltdev_close;
87 
88     ltdev->device.get_local_time = ltdev_get_local_time;
89     ltdev->device.get_local_freq = ltdev_get_local_freq;
90     ltdev->device.set_local_slew = NULL;
91     ltdev->device.get_debug_log  = NULL;
92 
93     *device = &ltdev->device.common;
94 
95     return 0;
96 }
97 
98 static struct hw_module_methods_t hal_module_methods = {
99     .open = ltdev_open,
100 };
101 
102 struct local_time_module HAL_MODULE_INFO_SYM = {
103     .common = {
104         .tag = HARDWARE_MODULE_TAG,
105         .version_major = 1,
106         .version_minor = 0,
107         .id = LOCAL_TIME_HARDWARE_MODULE_ID,
108         .name = "Default local_time HW HAL",
109         .author = "The Android Open Source Project",
110         .methods = &hal_module_methods,
111     },
112 };
113