1 /*
2  * Copyright (c) 2014 Intel Corporation All Rights Reserved
3  * Copyright (C) 2012 The Android Open Source Project
4  *
5  * Licensed under the Apache License, Version 2.0 (the "License");
6  * you may not use this file except in compliance with the License.
7  * You may obtain a copy of the License at
8  *
9  *      http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  */
17 
18 #include <sys/types.h>
19 #include <sys/stat.h>
20 #include <fcntl.h>
21 #include <stdlib.h>
22 
23 //#define LOG_NDEBUG 0
24 #define LOG_TAG "IntelPowerHAL"
25 #include <utils/Log.h>
26 
27 #include <hardware/hardware.h>
28 #include <hardware/power.h>
29 
30 #define BOOST_PULSE_SYSFS    "/sys/devices/system/cpu/cpufreq/interactive/boostpulse"
31 #define BOOST_FREQ_SYSFS     "/sys/devices/system/cpu/cpufreq/interactive/hispeed_freq"
32 #define BOOST_DURATION_SYSFS "/sys/devices/system/cpu/cpufreq/interactive/boostpulse_duration"
33 
34 struct intel_power_module {
35     struct power_module container;
36     uint32_t pulse_duration;
37     struct timespec last_boost_time; /* latest POWER_HINT_INTERACTION boost */
38 };
39 
sysfs_write(char * path,char * s)40 static ssize_t sysfs_write(char *path, char *s)
41 {
42     char buf[80];
43     ssize_t len;
44     int fd = open(path, O_WRONLY);
45 
46     if (fd < 0) {
47         strerror_r(errno, buf, sizeof(buf));
48         ALOGE("Error opening %s: %s\n", path, buf);
49         return -1;
50     }
51 
52     if ((len = write(fd, s, strlen(s))) < 0) {
53         strerror_r(errno, buf, sizeof(buf));
54         ALOGE("Error writing to %s: %s\n", path, buf);
55     }
56 
57     close(fd);
58     ALOGV("wrote '%s' to %s", s, path);
59 
60     return len;
61 }
62 
sysfs_read(char * path,char * s,int num_bytes)63 static ssize_t sysfs_read(char *path, char *s, int num_bytes)
64 {
65     char buf[80];
66     ssize_t count;
67     int fd = open(path, O_RDONLY);
68 
69     if (fd < 0) {
70         strerror_r(errno, buf, sizeof(buf));
71         ALOGE("Error reading from %s: %s\n", path, buf);
72         return -1;
73     }
74 
75     if ((count = read(fd, s, (num_bytes - 1))) < 0) {
76         strerror_r(errno, buf, sizeof(buf));
77         ALOGE("Error reading from  %s: %s\n", path, buf);
78     } else {
79         if ((count >= 1) && (s[count-1] == '\n')) {
80             s[count-1] = '\0';
81         } else {
82             s[count] = '\0';
83         }
84     }
85 
86     close(fd);
87     ALOGV("read '%s' from %s", s, path);
88 
89     return count;
90 }
91 
fugu_power_init(struct power_module * module)92 static void fugu_power_init(struct power_module *module)
93 {
94     struct intel_power_module *mod = (struct intel_power_module *) module;
95     char boost_freq[32];
96     char boostpulse_duration[32];
97 
98     /* Keep default boost_freq for fugu => max freq */
99 
100     if (sysfs_read(BOOST_FREQ_SYSFS, boost_freq, 32) < 0) {
101         strcpy(boost_freq, "?");
102     }
103     if (sysfs_read(BOOST_DURATION_SYSFS, boostpulse_duration, 32) < 0) {
104         /* above should not fail but just in case it does use an arbitrary 20ms value */
105         snprintf(boostpulse_duration, 32, "%d", 20000);
106     }
107     mod->pulse_duration = atoi(boostpulse_duration);
108     /* initialize last_boost_time */
109     clock_gettime(CLOCK_MONOTONIC, &mod->last_boost_time);
110 
111     ALOGI("init done: will boost CPU to %skHz for %dus on input events",
112             boost_freq, mod->pulse_duration);
113 }
114 
fugu_power_set_interactive(struct power_module * module,int on)115 static void fugu_power_set_interactive(struct power_module *module, int on)
116 {
117     struct dirent **device_list = NULL;
118 
119     ALOGI("setInteractive: on=%d", on);
120     (void) module; /* unused */
121     (void) on; /* unused */
122 }
123 
timespec_sub(struct timespec * res,struct timespec * a,struct timespec * b)124 static inline void timespec_sub(struct timespec *res, struct timespec *a, struct timespec *b)
125 {
126     res->tv_sec = a->tv_sec - b->tv_sec;
127     if (a->tv_sec >= b->tv_sec) {
128         res->tv_nsec = a->tv_nsec - b->tv_nsec;
129     } else {
130         res->tv_nsec = 1000000000 - b->tv_nsec + a->tv_nsec;
131         res->tv_sec--;
132     }
133 }
134 
timespec_to_us(struct timespec * t)135 static inline uint64_t timespec_to_us(struct timespec *t)
136 {
137     return t->tv_sec * 1000000 + t->tv_nsec / 1000;
138 }
139 
fugu_power_hint(struct power_module * module,power_hint_t hint,void * data)140 static void fugu_power_hint(struct power_module *module, power_hint_t hint, void *data)
141 {
142     struct intel_power_module *mod = (struct intel_power_module *) module;
143     char sysfs_val[80];
144     struct timespec curr_time;
145     struct timespec diff_time;
146     uint64_t diff;
147 
148     (void) data;
149 
150     switch (hint) {
151         case POWER_HINT_INTERACTION:
152             clock_gettime(CLOCK_MONOTONIC, &curr_time);
153             timespec_sub(&diff_time, &curr_time, &mod->last_boost_time);
154             diff = timespec_to_us(&diff_time);
155 
156             ALOGV("POWER_HINT_INTERACTION: diff=%llu", diff);
157 
158             if (diff > mod->pulse_duration) {
159                 sysfs_write(BOOST_PULSE_SYSFS, "1");
160                 mod->last_boost_time = curr_time;
161             }
162             break;
163         case POWER_HINT_VSYNC:
164             break;
165         default:
166             break;
167     }
168 }
169 
170 static struct hw_module_methods_t power_module_methods = {
171     .open = NULL,
172 };
173 
174 struct intel_power_module HAL_MODULE_INFO_SYM = {
175     container:{
176         common: {
177             tag: HARDWARE_MODULE_TAG,
178             module_api_version: POWER_MODULE_API_VERSION_0_2,
179             hal_api_version: HARDWARE_HAL_API_VERSION,
180             id: POWER_HARDWARE_MODULE_ID,
181             name: "Fugu Power HAL",
182             author: "Intel",
183             methods: &power_module_methods,
184         },
185         init: fugu_power_init,
186         setInteractive: fugu_power_set_interactive,
187         powerHint: fugu_power_hint,
188     },
189 };
190