blob: 7b084500cde2325235f56e31e5b852fe2cde751f [file] [log] [blame]
/*
* Copyright (C) 2017 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define LOG_TAG "android.hardware.usb@1.1-service.wahoo"
#include <android-base/logging.h>
#include <assert.h>
#include <chrono>
#include <dirent.h>
#include <pthread.h>
#include <regex>
#include <stdio.h>
#include <sys/types.h>
#include <thread>
#include <unistd.h>
#include <unordered_map>
#include <cutils/uevent.h>
#include <sys/epoll.h>
#include <utils/Errors.h>
#include <utils/StrongPointer.h>
#include "Usb.h"
namespace android {
namespace hardware {
namespace usb {
namespace V1_1 {
namespace implementation {
const char GOOGLE_USB_VENDOR_ID_STR[] = "18d1";
const char GOOGLE_USBC_35_ADAPTER_UNPLUGGED_ID_STR[] = "5029";
// Set by the signal handler to destroy the thread
volatile bool destroyThread;
static void checkUsbDeviceAutoSuspend(const std::string& devicePath);
static int32_t readFile(const std::string &filename, std::string *contents) {
FILE *fp;
ssize_t read = 0;
char *line = NULL;
size_t len = 0;
fp = fopen(filename.c_str(), "r");
if (fp != NULL) {
if ((read = getline(&line, &len, fp)) != -1) {
char *pos;
if ((pos = strchr(line, '\n')) != NULL) *pos = '\0';
*contents = line;
}
free(line);
fclose(fp);
return 0;
} else {
ALOGE("fopen failed in readFile %s, errno=%d", filename.c_str(), errno);
}
return -1;
}
static int32_t writeFile(const std::string &filename,
const std::string &contents) {
FILE *fp;
int ret;
fp = fopen(filename.c_str(), "w");
if (fp != NULL) {
ret = fputs(contents.c_str(), fp);
fclose(fp);
if (ret == EOF) {
ALOGE("fputs failed in writeFile %s", filename.c_str());
return -1;
}
return 0;
} else {
ALOGE("fopen failed in writeFile %s, errno=%d", filename.c_str(), errno);
}
return -1;
}
std::string appendRoleNodeHelper(const std::string &portName,
PortRoleType type) {
std::string node("/sys/class/typec/" + portName);
switch (type) {
case PortRoleType::DATA_ROLE:
return node + "/data_role";
case PortRoleType::POWER_ROLE:
return node + "/power_role";
case PortRoleType::MODE:
return node + "/port_type";
default:
return "";
}
}
std::string convertRoletoString(PortRole role) {
if (role.type == PortRoleType::POWER_ROLE) {
if (role.role == static_cast<uint32_t>(PortPowerRole::SOURCE))
return "source";
else if (role.role == static_cast<uint32_t>(PortPowerRole::SINK))
return "sink";
} else if (role.type == PortRoleType::DATA_ROLE) {
if (role.role == static_cast<uint32_t>(PortDataRole::HOST)) return "host";
if (role.role == static_cast<uint32_t>(PortDataRole::DEVICE))
return "device";
} else if (role.type == PortRoleType::MODE) {
if (role.role == static_cast<uint32_t>(PortMode_1_1::UFP)) return "sink";
if (role.role == static_cast<uint32_t>(PortMode_1_1::DFP)) return "source";
}
return "none";
}
void extractRole(std::string *roleName) {
std::size_t first, last;
first = roleName->find("[");
last = roleName->find("]");
if (first != std::string::npos && last != std::string::npos) {
*roleName = roleName->substr(first + 1, last - first - 1);
}
}
void switchToDrp(const std::string &portName) {
std::string filename =
appendRoleNodeHelper(std::string(portName.c_str()), PortRoleType::MODE);
FILE *fp;
if (filename != "") {
fp = fopen(filename.c_str(), "w");
if (fp != NULL) {
int ret = fputs("dual", fp);
fclose(fp);
if (ret == EOF)
ALOGE("Fatal: Error while switching back to drp");
} else {
ALOGE("Fatal: Cannot open file to switch back to drp");
}
} else {
ALOGE("Fatal: invalid node type");
}
}
bool switchMode(const hidl_string &portName,
const PortRole &newRole, struct Usb *usb) {
std::string filename =
appendRoleNodeHelper(std::string(portName.c_str()), newRole.type);
std::string written;
FILE *fp;
bool roleSwitch = false;
if (filename == "") {
ALOGE("Fatal: invalid node type");
return false;
}
fp = fopen(filename.c_str(), "w");
if (fp != NULL) {
// Hold the lock here to prevent loosing connected signals
// as once the file is written the partner added signal
// can arrive anytime.
pthread_mutex_lock(&usb->mPartnerLock);
usb->mPartnerUp = false;
int ret = fputs(convertRoletoString(newRole).c_str(), fp);
fclose(fp);
if (ret != EOF) {
struct timespec to;
struct timespec now;
wait_again:
clock_gettime(CLOCK_MONOTONIC, &now);
to.tv_sec = now.tv_sec + PORT_TYPE_TIMEOUT;
to.tv_nsec = now.tv_nsec;
int err = pthread_cond_timedwait(&usb->mPartnerCV, &usb->mPartnerLock, &to);
// There are no uevent signals which implies role swap timed out.
if (err == ETIMEDOUT) {
ALOGI("uevents wait timedout");
// Sanity check.
} else if (!usb->mPartnerUp) {
goto wait_again;
// Role switch succeeded since usb->mPartnerUp is true.
} else {
roleSwitch = true;
}
} else {
ALOGI("Role switch failed while wrting to file");
}
pthread_mutex_unlock(&usb->mPartnerLock);
}
if (!roleSwitch)
switchToDrp(std::string(portName.c_str()));
return roleSwitch;
}
Usb::Usb()
: mLock(PTHREAD_MUTEX_INITIALIZER),
mRoleSwitchLock(PTHREAD_MUTEX_INITIALIZER),
mPartnerLock(PTHREAD_MUTEX_INITIALIZER),
mPartnerUp(false) {
pthread_condattr_t attr;
if (pthread_condattr_init(&attr)) {
ALOGE("pthread_condattr_init failed: %s", strerror(errno));
abort();
}
if (pthread_condattr_setclock(&attr, CLOCK_MONOTONIC)) {
ALOGE("pthread_condattr_setclock failed: %s", strerror(errno));
abort();
}
if (pthread_cond_init(&mPartnerCV, &attr)) {
ALOGE("pthread_cond_init failed: %s", strerror(errno));
abort();
}
if (pthread_condattr_destroy(&attr)) {
ALOGE("pthread_condattr_destroy failed: %s", strerror(errno));
abort();
}
}
Return<void> Usb::switchRole(const hidl_string &portName,
const PortRole &newRole) {
std::string filename =
appendRoleNodeHelper(std::string(portName.c_str()), newRole.type);
std::string written;
FILE *fp;
bool roleSwitch = false;
if (filename == "") {
ALOGE("Fatal: invalid node type");
return Void();
}
pthread_mutex_lock(&mRoleSwitchLock);
ALOGI("filename write: %s role:%s", filename.c_str(),
convertRoletoString(newRole).c_str());
if (newRole.type == PortRoleType::MODE) {
roleSwitch = switchMode(portName, newRole, this);
} else {
fp = fopen(filename.c_str(), "w");
if (fp != NULL) {
int ret = fputs(convertRoletoString(newRole).c_str(), fp);
fclose(fp);
if ((ret != EOF) && !readFile(filename, &written)) {
extractRole(&written);
ALOGI("written: %s", written.c_str());
if (written == convertRoletoString(newRole)) {
roleSwitch = true;
} else {
ALOGE("Role switch failed");
}
} else {
ALOGE("failed to update the new role");
}
} else {
ALOGE("fopen failed");
}
}
pthread_mutex_lock(&mLock);
if (mCallback_1_0 != NULL) {
Return<void> ret =
mCallback_1_0->notifyRoleSwitchStatus(portName, newRole,
roleSwitch ? Status::SUCCESS : Status::ERROR);
if (!ret.isOk())
ALOGE("RoleSwitchStatus error %s", ret.description().c_str());
} else {
ALOGE("Not notifying the userspace. Callback is not set");
}
pthread_mutex_unlock(&mLock);
pthread_mutex_unlock(&mRoleSwitchLock);
return Void();
}
Status getAccessoryConnected(const std::string &portName, std::string *accessory) {
std::string filename =
"/sys/class/typec/" + portName + "-partner/accessory_mode";
if (readFile(filename, accessory)) {
ALOGE("getAccessoryConnected: Failed to open filesystem node: %s",
filename.c_str());
return Status::ERROR;
}
return Status::SUCCESS;
}
Status getCurrentRoleHelper(const std::string &portName, bool connected,
PortRoleType type, uint32_t *currentRole) {
std::string filename;
std::string roleName;
std::string accessory;
// Mode
if (type == PortRoleType::POWER_ROLE) {
filename = "/sys/class/typec/" + portName + "/power_role";
*currentRole = static_cast<uint32_t>(PortPowerRole::NONE);
} else if (type == PortRoleType::DATA_ROLE) {
filename = "/sys/class/typec/" + portName + "/data_role";
*currentRole = static_cast<uint32_t>(PortDataRole::NONE);
} else if (type == PortRoleType::MODE) {
filename = "/sys/class/typec/" + portName + "/data_role";
*currentRole = static_cast<uint32_t>(PortMode_1_1::NONE);
} else {
return Status::ERROR;
}
if (!connected) return Status::SUCCESS;
if (type == PortRoleType::MODE) {
if (getAccessoryConnected(portName, &accessory) != Status::SUCCESS) {
return Status::ERROR;
}
if (accessory == "analog_audio") {
*currentRole = static_cast<uint32_t>(PortMode_1_1::AUDIO_ACCESSORY);
return Status::SUCCESS;
} else if (accessory == "debug") {
*currentRole = static_cast<uint32_t>(PortMode_1_1::DEBUG_ACCESSORY);
return Status::SUCCESS;
}
}
if (readFile(filename, &roleName)) {
ALOGE("getCurrentRole: Failed to open filesystem node: %s",
filename.c_str());
return Status::ERROR;
}
extractRole(&roleName);
if (roleName == "source") {
*currentRole = static_cast<uint32_t>(PortPowerRole::SOURCE);
} else if (roleName == "sink") {
*currentRole = static_cast<uint32_t>(PortPowerRole::SINK);
} else if (roleName == "host") {
if (type == PortRoleType::DATA_ROLE)
*currentRole = static_cast<uint32_t>(PortDataRole::HOST);
else
*currentRole = static_cast<uint32_t>(PortMode_1_1::DFP);
} else if (roleName == "device") {
if (type == PortRoleType::DATA_ROLE)
*currentRole = static_cast<uint32_t>(PortDataRole::DEVICE);
else
*currentRole = static_cast<uint32_t>(PortMode_1_1::UFP);
} else if (roleName != "none") {
/* case for none has already been addressed.
* so we check if the role isnt none.
*/
return Status::UNRECOGNIZED_ROLE;
}
return Status::SUCCESS;
}
Status getTypeCPortNamesHelper(std::unordered_map<std::string, bool> *names) {
DIR *dp;
dp = opendir("/sys/class/typec");
if (dp != NULL) {
int32_t ports = 0;
int32_t current = 0;
struct dirent *ep;
while ((ep = readdir(dp))) {
if (ep->d_type == DT_LNK) {
if (std::string::npos == std::string(ep->d_name).find("-partner")) {
std::unordered_map<std::string, bool>::const_iterator portName =
names->find(ep->d_name);
if (portName == names->end()) {
names->insert({ep->d_name, false});
}
} else {
(*names)[std::strtok(ep->d_name, "-")] = true;
}
}
}
closedir(dp);
return Status::SUCCESS;
}
ALOGE("Failed to open /sys/class/typec");
return Status::ERROR;
}
bool canSwitchRoleHelper(const std::string &portName, PortRoleType /*type*/) {
std::string filename =
"/sys/class/typec/" + portName + "-partner/supports_usb_power_delivery";
std::string supportsPD;
if (!readFile(filename, &supportsPD)) {
if (supportsPD == "yes") {
return true;
}
}
return false;
}
/*
* Reuse the same method for both V1_0 and V1_1 callback objects.
* The caller of this method would reconstruct the V1_0::PortStatus
* object if required.
*/
Status getPortStatusHelper(hidl_vec<PortStatus_1_1> *currentPortStatus_1_1,
bool V1_0) {
std::unordered_map<std::string, bool> names;
Status result = getTypeCPortNamesHelper(&names);
int i = -1;
if (result == Status::SUCCESS) {
currentPortStatus_1_1->resize(names.size());
for (std::pair<std::string, bool> port : names) {
i++;
ALOGI("%s", port.first.c_str());
(*currentPortStatus_1_1)[i].status.portName = port.first;
uint32_t currentRole;
if (getCurrentRoleHelper(port.first, port.second,
PortRoleType::POWER_ROLE,
&currentRole) == Status::SUCCESS) {
(*currentPortStatus_1_1)[i].status.currentPowerRole =
static_cast<PortPowerRole>(currentRole);
} else {
ALOGE("Error while retreiving portNames");
goto done;
}
if (getCurrentRoleHelper(port.first, port.second, PortRoleType::DATA_ROLE,
&currentRole) == Status::SUCCESS) {
(*currentPortStatus_1_1)[i].status.currentDataRole =
static_cast<PortDataRole>(currentRole);
} else {
ALOGE("Error while retreiving current port role");
goto done;
}
if (getCurrentRoleHelper(port.first, port.second, PortRoleType::MODE,
&currentRole) == Status::SUCCESS) {
(*currentPortStatus_1_1)[i].currentMode =
static_cast<PortMode_1_1>(currentRole);
(*currentPortStatus_1_1)[i].status.currentMode =
static_cast<V1_0::PortMode>(currentRole);
} else {
ALOGE("Error while retreiving current data role");
goto done;
}
(*currentPortStatus_1_1)[i].status.canChangeMode = true;
(*currentPortStatus_1_1)[i].status.canChangeDataRole =
port.second ? canSwitchRoleHelper(port.first, PortRoleType::DATA_ROLE)
: false;
(*currentPortStatus_1_1)[i].status.canChangePowerRole =
port.second
? canSwitchRoleHelper(port.first, PortRoleType::POWER_ROLE)
: false;
ALOGI("connected:%d canChangeMode:%d canChagedata:%d canChangePower:%d",
port.second, (*currentPortStatus_1_1)[i].status.canChangeMode,
(*currentPortStatus_1_1)[i].status.canChangeDataRole,
(*currentPortStatus_1_1)[i].status.canChangePowerRole);
if (V1_0) {
(*currentPortStatus_1_1)[i].status.supportedModes = V1_0::PortMode::DFP;
} else {
(*currentPortStatus_1_1)[i].supportedModes = PortMode_1_1::UFP | PortMode_1_1::DFP;
(*currentPortStatus_1_1)[i].status.supportedModes = V1_0::PortMode::NONE;
(*currentPortStatus_1_1)[i].status.currentMode = V1_0::PortMode::NONE;
}
}
return Status::SUCCESS;
}
done:
return Status::ERROR;
}
Return<void> Usb::queryPortStatus() {
hidl_vec<PortStatus_1_1> currentPortStatus_1_1;
hidl_vec<V1_0::PortStatus> currentPortStatus;
Status status;
sp<IUsbCallback> callback_V1_1 = IUsbCallback::castFrom(mCallback_1_0);
pthread_mutex_lock(&mLock);
if (mCallback_1_0 != NULL) {
if (callback_V1_1 != NULL) {
status = getPortStatusHelper(&currentPortStatus_1_1, false);
} else {
status = getPortStatusHelper(&currentPortStatus_1_1, true);
currentPortStatus.resize(currentPortStatus_1_1.size());
for (unsigned long i = 0; i < currentPortStatus_1_1.size(); i++)
currentPortStatus[i] = currentPortStatus_1_1[i].status;
}
Return<void> ret;
if (callback_V1_1 != NULL)
ret = callback_V1_1->notifyPortStatusChange_1_1(currentPortStatus_1_1, status);
else
ret = mCallback_1_0->notifyPortStatusChange(currentPortStatus, status);
if (!ret.isOk())
ALOGE("queryPortStatus_1_1 error %s", ret.description().c_str());
} else {
ALOGI("Notifying userspace skipped. Callback is NULL");
}
pthread_mutex_unlock(&mLock);
return Void();
}
struct data {
int uevent_fd;
android::hardware::usb::V1_1::implementation::Usb *usb;
};
static void uevent_event(uint32_t /*epevents*/, struct data *payload) {
char msg[UEVENT_MSG_LEN + 2];
char *cp;
int n;
n = uevent_kernel_multicast_recv(payload->uevent_fd, msg, UEVENT_MSG_LEN);
if (n <= 0) return;
if (n >= UEVENT_MSG_LEN) /* overflow -- discard */
return;
msg[n] = '\0';
msg[n + 1] = '\0';
cp = msg;
while (*cp) {
std::cmatch match;
if (std::regex_match(cp, std::regex("(add)(.*)(-partner)"))) {
ALOGI("partner added");
pthread_mutex_lock(&payload->usb->mPartnerLock);
payload->usb->mPartnerUp = true;
pthread_cond_signal(&payload->usb->mPartnerCV);
pthread_mutex_unlock(&payload->usb->mPartnerLock);
} else if (!strncmp(cp, "DEVTYPE=typec_", strlen("DEVTYPE=typec_"))) {
hidl_vec<PortStatus_1_1> currentPortStatus_1_1;
ALOGI("uevent received %s", cp);
pthread_mutex_lock(&payload->usb->mLock);
if (payload->usb->mCallback_1_0 != NULL) {
sp<IUsbCallback> callback_V1_1 = IUsbCallback::castFrom(payload->usb->mCallback_1_0);
Return<void> ret;
// V1_1 callback
if (callback_V1_1 != NULL) {
Status status = getPortStatusHelper(&currentPortStatus_1_1, false);
ret = callback_V1_1->notifyPortStatusChange_1_1(
currentPortStatus_1_1, status);
} else { // V1_0 callback
Status status = getPortStatusHelper(&currentPortStatus_1_1, true);
/*
* Copying the result from getPortStatusHelper
* into V1_0::PortStatus to pass back through
* the V1_0 callback object.
*/
hidl_vec<V1_0::PortStatus> currentPortStatus;
currentPortStatus.resize(currentPortStatus_1_1.size());
for (unsigned long i = 0; i < currentPortStatus_1_1.size(); i++)
currentPortStatus[i] = currentPortStatus_1_1[i].status;
ret = payload->usb->mCallback_1_0->notifyPortStatusChange(
currentPortStatus, status);
}
if (!ret.isOk()) ALOGE("error %s", ret.description().c_str());
} else {
ALOGI("Notifying userspace skipped. Callback is NULL");
}
pthread_mutex_unlock(&payload->usb->mLock);
//Role switch is not in progress and port is in disconnected state
if (!pthread_mutex_trylock(&payload->usb->mRoleSwitchLock)) {
for (unsigned long i = 0; i < currentPortStatus_1_1.size(); i++) {
DIR *dp = opendir(std::string("/sys/class/typec/"
+ std::string(currentPortStatus_1_1[i].status.portName.c_str())
+ "-partner").c_str());
if (dp == NULL) {
//PortRole role = {.role = static_cast<uint32_t>(PortMode::UFP)};
switchToDrp(currentPortStatus_1_1[i].status.portName);
} else {
closedir(dp);
}
}
pthread_mutex_unlock(&payload->usb->mRoleSwitchLock);
}
break;
} else if (std::regex_match(cp, match,
std::regex("add@(/devices/soc/a800000\\.ssusb/a800000\\.dwc3/xhci-hcd\\.0\\.auto/"
"usb\\d/\\d-\\d)/.*"))) {
if (match.size() == 2) {
std::csub_match submatch = match[1];
checkUsbDeviceAutoSuspend("/sys" + submatch.str());
}
}
/* advance to after the next \0 */
while (*cp++) {}
}
}
void *work(void *param) {
int epoll_fd, uevent_fd;
struct epoll_event ev;
int nevents = 0;
struct data payload;
ALOGE("creating thread");
uevent_fd = uevent_open_socket(64 * 1024, true);
if (uevent_fd < 0) {
ALOGE("uevent_init: uevent_open_socket failed\n");
return NULL;
}
payload.uevent_fd = uevent_fd;
payload.usb = (android::hardware::usb::V1_1::implementation::Usb *)param;
fcntl(uevent_fd, F_SETFL, O_NONBLOCK);
ev.events = EPOLLIN;
ev.data.ptr = (void *)uevent_event;
epoll_fd = epoll_create(64);
if (epoll_fd == -1) {
ALOGE("epoll_create failed; errno=%d", errno);
goto error;
}
if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, uevent_fd, &ev) == -1) {
ALOGE("epoll_ctl failed; errno=%d", errno);
goto error;
}
while (!destroyThread) {
struct epoll_event events[64];
nevents = epoll_wait(epoll_fd, events, 64, -1);
if (nevents == -1) {
if (errno == EINTR) continue;
ALOGE("usb epoll_wait failed; errno=%d", errno);
break;
}
for (int n = 0; n < nevents; ++n) {
if (events[n].data.ptr)
(*(void (*)(int, struct data *payload))events[n].data.ptr)(
events[n].events, &payload);
}
}
ALOGI("exiting worker thread");
error:
close(uevent_fd);
if (epoll_fd >= 0) close(epoll_fd);
return NULL;
}
void sighandler(int sig) {
if (sig == SIGUSR1) {
destroyThread = true;
ALOGI("destroy set");
return;
}
signal(SIGUSR1, sighandler);
}
Return<void> Usb::setCallback(const sp<V1_0::IUsbCallback> &callback) {
sp<IUsbCallback> callback_V1_1 = IUsbCallback::castFrom(callback);
if (callback != NULL)
if (callback_V1_1 == NULL)
ALOGI("Registering 1.0 callback");
pthread_mutex_lock(&mLock);
/*
* When both the old callback and new callback values are NULL,
* there is no need to spin off the worker thread.
* When both the values are not NULL, we would already have a
* worker thread running, so updating the callback object would
* be suffice.
*/
if ((mCallback_1_0 == NULL && callback == NULL) ||
(mCallback_1_0 != NULL && callback != NULL)) {
/*
* Always store as V1_0 callback object. Type cast to V1_1
* when the callback is actually invoked.
*/
mCallback_1_0 = callback;
pthread_mutex_unlock(&mLock);
return Void();
}
mCallback_1_0 = callback;
ALOGI("registering callback");
// Kill the worker thread if the new callback is NULL.
if (mCallback_1_0 == NULL) {
pthread_mutex_unlock(&mLock);
if (!pthread_kill(mPoll, SIGUSR1)) {
pthread_join(mPoll, NULL);
ALOGI("pthread destroyed");
}
return Void();
}
destroyThread = false;
signal(SIGUSR1, sighandler);
/*
* Create a background thread if the old callback value is NULL
* and being updated with a new value.
*/
if (pthread_create(&mPoll, NULL, work, this)) {
ALOGE("pthread creation failed %d", errno);
mCallback_1_0 = NULL;
}
pthread_mutex_unlock(&mLock);
return Void();
}
/*
* whitelisting USB device idProduct and idVendor to allow auto suspend.
*/
static bool canProductAutoSuspend(const std::string &deviceIdVendor,
const std::string &deviceIdProduct) {
if (deviceIdVendor == GOOGLE_USB_VENDOR_ID_STR &&
deviceIdProduct == GOOGLE_USBC_35_ADAPTER_UNPLUGGED_ID_STR) {
return true;
}
return false;
}
static bool canUsbDeviceAutoSuspend(const std::string &devicePath) {
std::string deviceIdVendor;
std::string deviceIdProduct;
readFile(devicePath + "/idVendor", &deviceIdVendor);
readFile(devicePath + "/idProduct", &deviceIdProduct);
// deviceIdVendor and deviceIdProduct will be empty strings if readFile fails
return canProductAutoSuspend(deviceIdVendor, deviceIdProduct);
}
/*
* function to consume USB device plugin events (on receiving a
* USB device path string), and enable autosupend on the USB device if
* necessary.
*/
void checkUsbDeviceAutoSuspend(const std::string& devicePath) {
/*
* Currently we only actively enable devices that should be autosuspended, and leave others
* to the defualt.
*/
if (canUsbDeviceAutoSuspend(devicePath)) {
ALOGI("auto suspend usb device %s", devicePath.c_str());
writeFile(devicePath + "/power/control", "auto");
}
}
} // namespace implementation
} // namespace V1_0
} // namespace usb
} // namespace hardware
} // namespace android