platform_system_core/adb/usb_linux.cpp
Dan Albert d99d902abd Be tolerant of devices that don't report serials.
The USB spec explicitly says this is optional, so we shouldn't be
relying on it.

Bug: http://b/20883914
Change-Id: Icf38405b00275199bcf51a70c47d428ae7264f2b
2015-05-06 16:48:52 -07:00

683 lines
20 KiB
C++

/*
* Copyright (C) 2007 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 TRACE_TAG TRACE_USB
#include "sysdeps.h"
#include <ctype.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <linux/usbdevice_fs.h>
#include <linux/version.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>
#include <linux/usb/ch9.h>
#include <base/file.h>
#include <base/stringprintf.h>
#include <base/strings.h>
#include "adb.h"
#include "transport.h"
/* usb scan debugging is waaaay too verbose */
#define DBGX(x...)
ADB_MUTEX_DEFINE( usb_lock );
struct usb_handle
{
usb_handle *prev;
usb_handle *next;
char fname[64];
int desc;
unsigned char ep_in;
unsigned char ep_out;
unsigned zero_mask;
unsigned writeable;
struct usbdevfs_urb urb_in;
struct usbdevfs_urb urb_out;
int urb_in_busy;
int urb_out_busy;
int dead;
adb_cond_t notify;
adb_mutex_t lock;
// for garbage collecting disconnected devices
int mark;
// ID of thread currently in REAPURB
pthread_t reaper_thread;
};
static usb_handle handle_list = {
.prev = &handle_list,
.next = &handle_list,
};
static int known_device(const char *dev_name)
{
usb_handle *usb;
adb_mutex_lock(&usb_lock);
for(usb = handle_list.next; usb != &handle_list; usb = usb->next){
if(!strcmp(usb->fname, dev_name)) {
// set mark flag to indicate this device is still alive
usb->mark = 1;
adb_mutex_unlock(&usb_lock);
return 1;
}
}
adb_mutex_unlock(&usb_lock);
return 0;
}
static void kick_disconnected_devices()
{
usb_handle *usb;
adb_mutex_lock(&usb_lock);
// kick any devices in the device list that were not found in the device scan
for(usb = handle_list.next; usb != &handle_list; usb = usb->next){
if (usb->mark == 0) {
usb_kick(usb);
} else {
usb->mark = 0;
}
}
adb_mutex_unlock(&usb_lock);
}
static inline int badname(const char *name)
{
while(*name) {
if(!isdigit(*name++)) return 1;
}
return 0;
}
static void find_usb_device(const char *base,
void (*register_device_callback)
(const char *, const char *, unsigned char, unsigned char, int, int, unsigned))
{
char busname[32], devname[32];
unsigned char local_ep_in, local_ep_out;
DIR *busdir , *devdir ;
struct dirent *de;
int fd ;
busdir = opendir(base);
if(busdir == 0) return;
while((de = readdir(busdir)) != 0) {
if(badname(de->d_name)) continue;
snprintf(busname, sizeof busname, "%s/%s", base, de->d_name);
devdir = opendir(busname);
if(devdir == 0) continue;
// DBGX("[ scanning %s ]\n", busname);
while((de = readdir(devdir))) {
unsigned char devdesc[4096];
unsigned char* bufptr = devdesc;
unsigned char* bufend;
struct usb_device_descriptor* device;
struct usb_config_descriptor* config;
struct usb_interface_descriptor* interface;
struct usb_endpoint_descriptor *ep1, *ep2;
unsigned zero_mask = 0;
unsigned vid, pid;
size_t desclength;
if(badname(de->d_name)) continue;
snprintf(devname, sizeof devname, "%s/%s", busname, de->d_name);
if(known_device(devname)) {
DBGX("skipping %s\n", devname);
continue;
}
// DBGX("[ scanning %s ]\n", devname);
if((fd = unix_open(devname, O_RDONLY | O_CLOEXEC)) < 0) {
continue;
}
desclength = adb_read(fd, devdesc, sizeof(devdesc));
bufend = bufptr + desclength;
// should have device and configuration descriptors, and atleast two endpoints
if (desclength < USB_DT_DEVICE_SIZE + USB_DT_CONFIG_SIZE) {
D("desclength %zu is too small\n", desclength);
adb_close(fd);
continue;
}
device = (struct usb_device_descriptor*)bufptr;
bufptr += USB_DT_DEVICE_SIZE;
if((device->bLength != USB_DT_DEVICE_SIZE) || (device->bDescriptorType != USB_DT_DEVICE)) {
adb_close(fd);
continue;
}
vid = device->idVendor;
pid = device->idProduct;
DBGX("[ %s is V:%04x P:%04x ]\n", devname, vid, pid);
// should have config descriptor next
config = (struct usb_config_descriptor *)bufptr;
bufptr += USB_DT_CONFIG_SIZE;
if (config->bLength != USB_DT_CONFIG_SIZE || config->bDescriptorType != USB_DT_CONFIG) {
D("usb_config_descriptor not found\n");
adb_close(fd);
continue;
}
// loop through all the descriptors and look for the ADB interface
while (bufptr < bufend) {
unsigned char length = bufptr[0];
unsigned char type = bufptr[1];
if (type == USB_DT_INTERFACE) {
interface = (struct usb_interface_descriptor *)bufptr;
bufptr += length;
if (length != USB_DT_INTERFACE_SIZE) {
D("interface descriptor has wrong size\n");
break;
}
DBGX("bInterfaceClass: %d, bInterfaceSubClass: %d,"
"bInterfaceProtocol: %d, bNumEndpoints: %d\n",
interface->bInterfaceClass, interface->bInterfaceSubClass,
interface->bInterfaceProtocol, interface->bNumEndpoints);
if (interface->bNumEndpoints == 2 &&
is_adb_interface(vid, pid, interface->bInterfaceClass,
interface->bInterfaceSubClass, interface->bInterfaceProtocol)) {
struct stat st;
char pathbuf[128];
char link[256];
char *devpath = NULL;
DBGX("looking for bulk endpoints\n");
// looks like ADB...
ep1 = (struct usb_endpoint_descriptor *)bufptr;
bufptr += USB_DT_ENDPOINT_SIZE;
// For USB 3.0 SuperSpeed devices, skip potential
// USB 3.0 SuperSpeed Endpoint Companion descriptor
if (bufptr+2 <= devdesc + desclength &&
bufptr[0] == USB_DT_SS_EP_COMP_SIZE &&
bufptr[1] == USB_DT_SS_ENDPOINT_COMP) {
bufptr += USB_DT_SS_EP_COMP_SIZE;
}
ep2 = (struct usb_endpoint_descriptor *)bufptr;
bufptr += USB_DT_ENDPOINT_SIZE;
if (bufptr+2 <= devdesc + desclength &&
bufptr[0] == USB_DT_SS_EP_COMP_SIZE &&
bufptr[1] == USB_DT_SS_ENDPOINT_COMP) {
bufptr += USB_DT_SS_EP_COMP_SIZE;
}
if (bufptr > devdesc + desclength ||
ep1->bLength != USB_DT_ENDPOINT_SIZE ||
ep1->bDescriptorType != USB_DT_ENDPOINT ||
ep2->bLength != USB_DT_ENDPOINT_SIZE ||
ep2->bDescriptorType != USB_DT_ENDPOINT) {
D("endpoints not found\n");
break;
}
// both endpoints should be bulk
if (ep1->bmAttributes != USB_ENDPOINT_XFER_BULK ||
ep2->bmAttributes != USB_ENDPOINT_XFER_BULK) {
D("bulk endpoints not found\n");
continue;
}
/* aproto 01 needs 0 termination */
if(interface->bInterfaceProtocol == 0x01) {
zero_mask = ep1->wMaxPacketSize - 1;
}
// we have a match. now we just need to figure out which is in and which is out.
if (ep1->bEndpointAddress & USB_ENDPOINT_DIR_MASK) {
local_ep_in = ep1->bEndpointAddress;
local_ep_out = ep2->bEndpointAddress;
} else {
local_ep_in = ep2->bEndpointAddress;
local_ep_out = ep1->bEndpointAddress;
}
// Determine the device path
if (!fstat(fd, &st) && S_ISCHR(st.st_mode)) {
char *slash;
ssize_t link_len;
snprintf(pathbuf, sizeof(pathbuf), "/sys/dev/char/%d:%d",
major(st.st_rdev), minor(st.st_rdev));
link_len = readlink(pathbuf, link, sizeof(link) - 1);
if (link_len > 0) {
link[link_len] = '\0';
slash = strrchr(link, '/');
if (slash) {
snprintf(pathbuf, sizeof(pathbuf),
"usb:%s", slash + 1);
devpath = pathbuf;
}
}
}
register_device_callback(devname, devpath,
local_ep_in, local_ep_out,
interface->bInterfaceNumber, device->iSerialNumber, zero_mask);
break;
}
} else {
bufptr += length;
}
} // end of while
adb_close(fd);
} // end of devdir while
closedir(devdir);
} //end of busdir while
closedir(busdir);
}
void usb_cleanup()
{
}
static int usb_bulk_write(usb_handle *h, const void *data, int len)
{
struct usbdevfs_urb *urb = &h->urb_out;
int res;
struct timeval tv;
struct timespec ts;
memset(urb, 0, sizeof(*urb));
urb->type = USBDEVFS_URB_TYPE_BULK;
urb->endpoint = h->ep_out;
urb->status = -1;
urb->buffer = (void*) data;
urb->buffer_length = len;
D("++ write ++\n");
adb_mutex_lock(&h->lock);
if(h->dead) {
res = -1;
goto fail;
}
do {
res = ioctl(h->desc, USBDEVFS_SUBMITURB, urb);
} while((res < 0) && (errno == EINTR));
if(res < 0) {
goto fail;
}
res = -1;
h->urb_out_busy = 1;
for(;;) {
/* time out after five seconds */
gettimeofday(&tv, NULL);
ts.tv_sec = tv.tv_sec + 5;
ts.tv_nsec = tv.tv_usec * 1000L;
res = pthread_cond_timedwait(&h->notify, &h->lock, &ts);
if(res < 0 || h->dead) {
break;
}
if(h->urb_out_busy == 0) {
if(urb->status == 0) {
res = urb->actual_length;
}
break;
}
}
fail:
adb_mutex_unlock(&h->lock);
D("-- write --\n");
return res;
}
static int usb_bulk_read(usb_handle *h, void *data, int len)
{
struct usbdevfs_urb *urb = &h->urb_in;
struct usbdevfs_urb *out = NULL;
int res;
D("++ usb_bulk_read ++\n");
memset(urb, 0, sizeof(*urb));
urb->type = USBDEVFS_URB_TYPE_BULK;
urb->endpoint = h->ep_in;
urb->status = -1;
urb->buffer = data;
urb->buffer_length = len;
adb_mutex_lock(&h->lock);
if(h->dead) {
res = -1;
goto fail;
}
do {
res = ioctl(h->desc, USBDEVFS_SUBMITURB, urb);
} while((res < 0) && (errno == EINTR));
if(res < 0) {
goto fail;
}
h->urb_in_busy = 1;
for(;;) {
D("[ reap urb - wait ]\n");
h->reaper_thread = pthread_self();
adb_mutex_unlock(&h->lock);
res = ioctl(h->desc, USBDEVFS_REAPURB, &out);
int saved_errno = errno;
adb_mutex_lock(&h->lock);
h->reaper_thread = 0;
if(h->dead) {
res = -1;
break;
}
if(res < 0) {
if(saved_errno == EINTR) {
continue;
}
D("[ reap urb - error ]\n");
break;
}
D("[ urb @%p status = %d, actual = %d ]\n",
out, out->status, out->actual_length);
if(out == &h->urb_in) {
D("[ reap urb - IN complete ]\n");
h->urb_in_busy = 0;
if(urb->status == 0) {
res = urb->actual_length;
} else {
res = -1;
}
break;
}
if(out == &h->urb_out) {
D("[ reap urb - OUT compelete ]\n");
h->urb_out_busy = 0;
adb_cond_broadcast(&h->notify);
}
}
fail:
adb_mutex_unlock(&h->lock);
D("-- usb_bulk_read --\n");
return res;
}
int usb_write(usb_handle *h, const void *_data, int len)
{
unsigned char *data = (unsigned char*) _data;
int n;
int need_zero = 0;
D("++ usb_write ++\n");
if(h->zero_mask) {
/* if we need 0-markers and our transfer
** is an even multiple of the packet size,
** we make note of it
*/
if(!(len & h->zero_mask)) {
need_zero = 1;
}
}
while(len > 0) {
int xfer = (len > 4096) ? 4096 : len;
n = usb_bulk_write(h, data, xfer);
if(n != xfer) {
D("ERROR: n = %d, errno = %d (%s)\n",
n, errno, strerror(errno));
return -1;
}
len -= xfer;
data += xfer;
}
if(need_zero){
n = usb_bulk_write(h, _data, 0);
return n;
}
D("-- usb_write --\n");
return 0;
}
int usb_read(usb_handle *h, void *_data, int len)
{
unsigned char *data = (unsigned char*) _data;
int n;
D("++ usb_read ++\n");
while(len > 0) {
int xfer = (len > 4096) ? 4096 : len;
D("[ usb read %d fd = %d], fname=%s\n", xfer, h->desc, h->fname);
n = usb_bulk_read(h, data, xfer);
D("[ usb read %d ] = %d, fname=%s\n", xfer, n, h->fname);
if(n != xfer) {
if((errno == ETIMEDOUT) && (h->desc != -1)) {
D("[ timeout ]\n");
if(n > 0){
data += n;
len -= n;
}
continue;
}
D("ERROR: n = %d, errno = %d (%s)\n",
n, errno, strerror(errno));
return -1;
}
len -= xfer;
data += xfer;
}
D("-- usb_read --\n");
return 0;
}
void usb_kick(usb_handle *h)
{
D("[ kicking %p (fd = %d) ]\n", h, h->desc);
adb_mutex_lock(&h->lock);
if(h->dead == 0) {
h->dead = 1;
if (h->writeable) {
/* HACK ALERT!
** Sometimes we get stuck in ioctl(USBDEVFS_REAPURB).
** This is a workaround for that problem.
*/
if (h->reaper_thread) {
pthread_kill(h->reaper_thread, SIGALRM);
}
/* cancel any pending transactions
** these will quietly fail if the txns are not active,
** but this ensures that a reader blocked on REAPURB
** will get unblocked
*/
ioctl(h->desc, USBDEVFS_DISCARDURB, &h->urb_in);
ioctl(h->desc, USBDEVFS_DISCARDURB, &h->urb_out);
h->urb_in.status = -ENODEV;
h->urb_out.status = -ENODEV;
h->urb_in_busy = 0;
h->urb_out_busy = 0;
adb_cond_broadcast(&h->notify);
} else {
unregister_usb_transport(h);
}
}
adb_mutex_unlock(&h->lock);
}
int usb_close(usb_handle *h)
{
D("++ usb close ++\n");
adb_mutex_lock(&usb_lock);
h->next->prev = h->prev;
h->prev->next = h->next;
h->prev = 0;
h->next = 0;
adb_close(h->desc);
D("-- usb closed %p (fd = %d) --\n", h, h->desc);
adb_mutex_unlock(&usb_lock);
free(h);
return 0;
}
static void register_device(const char* dev_name, const char* dev_path,
unsigned char ep_in, unsigned char ep_out,
int interface, int serial_index,
unsigned zero_mask) {
// Since Linux will not reassign the device ID (and dev_name) as long as the
// device is open, we can add to the list here once we open it and remove
// from the list when we're finally closed and everything will work out
// fine.
//
// If we have a usb_handle on the list 'o handles with a matching name, we
// have no further work to do.
adb_mutex_lock(&usb_lock);
for (usb_handle* usb = handle_list.next; usb != &handle_list; usb = usb->next) {
if (!strcmp(usb->fname, dev_name)) {
adb_mutex_unlock(&usb_lock);
return;
}
}
adb_mutex_unlock(&usb_lock);
D("[ usb located new device %s (%d/%d/%d) ]\n", dev_name, ep_in, ep_out, interface);
usb_handle* usb = reinterpret_cast<usb_handle*>(calloc(1, sizeof(usb_handle)));
if (usb == nullptr) fatal("couldn't allocate usb_handle");
strcpy(usb->fname, dev_name);
usb->ep_in = ep_in;
usb->ep_out = ep_out;
usb->zero_mask = zero_mask;
usb->writeable = 1;
adb_cond_init(&usb->notify, 0);
adb_mutex_init(&usb->lock, 0);
// Initialize mark to 1 so we don't get garbage collected after the device
// scan.
usb->mark = 1;
usb->reaper_thread = 0;
usb->desc = unix_open(usb->fname, O_RDWR | O_CLOEXEC);
if (usb->desc == -1) {
// Opening RW failed, so see if we have RO access.
usb->desc = unix_open(usb->fname, O_RDONLY | O_CLOEXEC);
if (usb->desc == -1) {
D("[ usb open %s failed: %s]\n", usb->fname, strerror(errno));
free(usb);
return;
}
usb->writeable = 0;
}
D("[ usb opened %s%s, fd=%d]\n", usb->fname,
(usb->writeable ? "" : " (read-only)"), usb->desc);
if (usb->writeable) {
if (ioctl(usb->desc, USBDEVFS_CLAIMINTERFACE, &interface) != 0) {
D("[ usb ioctl(%d, USBDEVFS_CLAIMINTERFACE) failed: %s]\n",
usb->desc, strerror(errno));
adb_close(usb->desc);
free(usb);
return;
}
}
// Read the device's serial number.
std::string serial_path = android::base::StringPrintf(
"/sys/bus/usb/devices/%s/serial", dev_path + 4);
std::string serial;
if (!android::base::ReadFileToString(serial_path, &serial)) {
D("[ usb read %s failed: %s ]\n", serial_path.c_str(), strerror(errno));
// We don't actually want to treat an unknown serial as an error because
// devices aren't able to communicate a serial number in early bringup.
// http://b/20883914
serial = "";
}
serial = android::base::Trim(serial);
// Add to the end of the active handles.
adb_mutex_lock(&usb_lock);
usb->next = &handle_list;
usb->prev = handle_list.prev;
usb->prev->next = usb;
usb->next->prev = usb;
adb_mutex_unlock(&usb_lock);
register_usb_transport(usb, serial.c_str(), dev_path, usb->writeable);
}
static void* device_poll_thread(void* unused) {
D("Created device thread\n");
while (true) {
// TODO: Use inotify.
find_usb_device("/dev/bus/usb", register_device);
kick_disconnected_devices();
sleep(1);
}
return nullptr;
}
static void sigalrm_handler(int signo) {
// don't need to do anything here
}
void usb_init()
{
struct sigaction actions;
memset(&actions, 0, sizeof(actions));
sigemptyset(&actions.sa_mask);
actions.sa_flags = 0;
actions.sa_handler = sigalrm_handler;
sigaction(SIGALRM,& actions, NULL);
if (!adb_thread_create(device_poll_thread, nullptr)) {
fatal_errno("cannot create input thread");
}
}