/*
* Copyright (C) 2008 The Android Open Source Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <dirent.h>
#include <fcntl.h>
#include <errno.h>
#include <pthread.h>
#include <ctype.h>
#include <linux/usbdevice_fs.h>
#include <linux/usbdevice_fs.h>
#include <linux/version.h>
#if LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 20)
#include <linux/usb/ch9.h>
#else
#include <linux/usb_ch9.h>
#endif
#include <asm/byteorder.h>
#include "usb.h"
#define MAX_RETRIES 5
#ifdef TRACE_USB
#define DBG1(x...) fprintf(stderr, x)
#define DBG(x...) fprintf(stderr, x)
#else
#define DBG(x...)
#define DBG1(x...)
#endif
/* The max bulk size for linux is 16384 which is defined
* in drivers/usb/core/devio.c.
*/
#define MAX_USBFS_BULK_SIZE (16 * 1024)
struct usb_handle
{
char fname[64];
int desc;
unsigned char ep_in;
unsigned char ep_out;
};
static inline int badname(const char *name)
{
while(*name) {
if(!isdigit(*name++)) return 1;
}
return 0;
}
static int check(void *_desc, int len, unsigned type, int size)
{
unsigned char *desc = _desc;
if(len < size) return -1;
if(desc[0] < size) return -1;
if(desc[0] > len) return -1;
if(desc[1] != type) return -1;
return 0;
}
static int filter_usb_device(int fd, char *ptr, int len, int writable,
ifc_match_func callback,
int *ept_in_id, int *ept_out_id, int *ifc_id)
{
struct usb_device_descriptor *dev;
struct usb_config_descriptor *cfg;
struct usb_interface_descriptor *ifc;
struct usb_endpoint_descriptor *ept;
struct usb_ifc_info info;
int in, out;
unsigned i;
unsigned e;
struct stat st;
int result;
if(check(ptr, len, USB_DT_DEVICE, USB_DT_DEVICE_SIZE))
return -1;
dev = (void*) ptr;
len -= dev->bLength;
ptr += dev->bLength;
if(check(ptr, len, USB_DT_CONFIG, USB_DT_CONFIG_SIZE))
return -1;
cfg = (void*) ptr;
len -= cfg->bLength;
ptr += cfg->bLength;
info.dev_vendor = dev->idVendor;
info.dev_product = dev->idProduct;
info.dev_class = dev->bDeviceClass;
info.dev_subclass = dev->bDeviceSubClass;
info.dev_protocol = dev->bDeviceProtocol;
info.writable = writable;
// read device serial number (if there is one)
info.serial_number[0] = 0;
if (dev->iSerialNumber) {
struct usbdevfs_ctrltransfer ctrl;
// Keep it short enough because some bootloaders are borked if the URB len is > 255
// 128 is too big by 1.
__u16 buffer[127];
memset(buffer, 0, sizeof(buffer));
ctrl.bRequestType = USB_DIR_IN|USB_TYPE_STANDARD|USB_RECIP_DEVICE;
ctrl.bRequest = USB_REQ_GET_DESCRIPTOR;
ctrl.wValue = (USB_DT_STRING << 8) | dev->iSerialNumber;
//language ID (en-us) for serial number string
ctrl.wIndex = 0x0409;
ctrl.wLength = sizeof(buffer);
ctrl.data = buffer;
ctrl.timeout = 50;
result = ioctl(fd, USBDEVFS_CONTROL, &ctrl);
if (result > 0) {
int i;
// skip first word, and copy the rest to the serial string, changing shorts to bytes.
result /= 2;
for (i = 1; i < result; i++)
info.serial_number[i - 1] = buffer[i];
info.serial_number[i - 1] = 0;
}
}
/* We need to get a path that represents a particular port on a particular
* hub. We are passed an fd that was obtained by opening an entry under
* /dev/bus/usb. Unfortunately, the names of those entries change each
* time devices are plugged and unplugged. So how to get a repeatable
* path? udevadm provided the inspiration. We can get the major and
* minor of the device file, read the symlink that can be found here:
* /sys/dev/char/<major>:<minor>
* and then use the last element of that path. As a concrete example, I
* have an Android device at /dev/bus/usb/001/027 so working with bash:
* $ ls -l /dev/bus/usb/001/027
* crw-rw-r-- 1 root plugdev 189, 26 Apr 9 11:03 /dev/bus/usb/001/027
* $ ls -l /sys/dev/char/189:26
* lrwxrwxrwx 1 root root 0 Apr 9 11:03 /sys/dev/char/189:26 ->
* ../../devices/pci0000:00/0000:00:1a.7/usb1/1-4/1-4.2/1-4.2.3
* So our device_path would be 1-4.2.3 which says my device is connected
* to port 3 of a hub on port 2 of a hub on port 4 of bus 1 (per
* http://www.linux-usb.org/FAQ.html).
*/
info.device_path[0] = '\0';
result = fstat(fd, &st);
if (!result && S_ISCHR(st.st_mode)) {
char cdev[128];
char link[256];
char *slash;
ssize_t link_len;
snprintf(cdev, sizeof(cdev), "/sys/dev/char/%d:%d",
major(st.st_rdev), minor(st.st_rdev));
link_len = readlink(cdev, link, sizeof(link) - 1);
if (link_len > 0) {
link[link_len] = '\0';
slash = strrchr(link, '/');
if (slash)
snprintf(info.device_path, sizeof(info.device_path), "usb:%s", slash+1);
}
}
for(i = 0; i < cfg->bNumInterfaces; i++) {
if(check(ptr, len, USB_DT_INTERFACE, USB_DT_INTERFACE_SIZE))
return -1;
ifc = (void*) ptr;
len -= ifc->bLength;
ptr += ifc->bLength;
in = -1;
out = -1;
info.ifc_class = ifc->bInterfaceClass;
info.ifc_subclass = ifc->bInterfaceSubClass;
info.ifc_protocol = ifc->bInterfaceProtocol;
for(e = 0; e < ifc->bNumEndpoints; e++) {
if(check(ptr, len, USB_DT_ENDPOINT, USB_DT_ENDPOINT_SIZE))
return -1;
ept = (void*) ptr;
len -= ept->bLength;
ptr += ept->bLength;
if((ept->bmAttributes & 0x03) != 0x02)
continue;
if(ept->bEndpointAddress & 0x80) {
in = ept->bEndpointAddress;
} else {
out = ept->bEndpointAddress;
}
}
info.has_bulk_in = (in != -1);
info.has_bulk_out = (out != -1);
if(callback(&info) == 0) {
*ept_in_id = in;
*ept_out_id = out;
*ifc_id = ifc->bInterfaceNumber;
return 0;
}
}
return -1;
}
static usb_handle *find_usb_device(const char *base, ifc_match_func callback)
{
usb_handle *usb = 0;
char busname[64], devname[64];
char desc[1024];
int n, in, out, ifc;
DIR *busdir, *devdir;
struct dirent *de;
int fd;
int writable;
busdir = opendir(base);
if(busdir == 0) return 0;
while((de = readdir(busdir)) && (usb == 0)) {
if(badname(de->d_name)) continue;
sprintf(busname, "%s/%s", base, de->d_name);
devdir = opendir(busname);
if(devdir == 0) continue;
// DBG("[ scanning %s ]\n", busname);
while((de = readdir(devdir)) && (usb == 0)) {
if(badname(de->d_name)) continue;
sprintf(devname, "%s/%s", busname, de->d_name);
// DBG("[ scanning %s ]\n", devname);
writable = 1;
if((fd = open(devname, O_RDWR)) < 0) {
// Check if we have read-only access, so we can give a helpful
// diagnostic like "adb devices" does.
writable = 0;
if((fd = open(devname, O_RDONLY)) < 0) {
continue;
}
}
n = read(fd, desc, sizeof(desc));
if(filter_usb_device(fd, desc, n, writable, callback,
&in, &out, &ifc) == 0) {
usb = calloc(1, sizeof(usb_handle));
strcpy(usb->fname, devname);
usb->ep_in = in;
usb->ep_out = out;
usb->desc = fd;
n = ioctl(fd, USBDEVFS_CLAIMINTERFACE, &ifc);
if(n != 0) {
close(fd);
free(usb);
usb = 0;
continue;
}
} else {
close(fd);
}
}
closedir(devdir);
}
closedir(busdir);
return usb;
}
int usb_write(usb_handle *h, const void *_data, int len)
{
unsigned char *data = (unsigned char*) _data;
unsigned count = 0;
struct usbdevfs_bulktransfer bulk;
int n;
if(h->ep_out == 0) {
return -1;
}
if(len == 0) {
bulk.ep = h->ep_out;
bulk.len = 0;
bulk.data = data;
bulk.timeout = 0;
n = ioctl(h->desc, USBDEVFS_BULK, &bulk);
if(n != 0) {
fprintf(stderr,"ERROR: n = %d, errno = %d (%s)\n",
n, errno, strerror(errno));
return -1;
}
return 0;
}
while(len > 0) {
int xfer;
xfer = (len > MAX_USBFS_BULK_SIZE) ? MAX_USBFS_BULK_SIZE : len;
bulk.ep = h->ep_out;
bulk.len = xfer;
bulk.data = data;
bulk.timeout = 0;
n = ioctl(h->desc, USBDEVFS_BULK, &bulk);
if(n != xfer) {
DBG("ERROR: n = %d, errno = %d (%s)\n",
n, errno, strerror(errno));
return -1;
}
count += xfer;
len -= xfer;
data += xfer;
}
return count;
}
int usb_read(usb_handle *h, void *_data, int len)
{
unsigned char *data = (unsigned char*) _data;
unsigned count = 0;
struct usbdevfs_bulktransfer bulk;
int n, retry;
if(h->ep_in == 0) {
return -1;
}
while(len > 0) {
int xfer = (len > MAX_USBFS_BULK_SIZE) ? MAX_USBFS_BULK_SIZE : len;
bulk.ep = h->ep_in;
bulk.len = xfer;
bulk.data = data;
bulk.timeout = 0;
retry = 0;
do{
DBG("[ usb read %d fd = %d], fname=%s\n", xfer, h->desc, h->fname);
n = ioctl(h->desc, USBDEVFS_BULK, &bulk);
DBG("[ usb read %d ] = %d, fname=%s, Retry %d \n", xfer, n, h->fname, retry);
if( n < 0 ) {
DBG1("ERROR: n = %d, errno = %d (%s)\n",n, errno, strerror(errno));
if ( ++retry > MAX_RETRIES ) return -1;
sleep( 1 );
}
}
while( n < 0 );
count += n;
len -= n;
data += n;
if(n < xfer) {
break;
}
}
return count;
}
void usb_kick(usb_handle *h)
{
int fd;
fd = h->desc;
h->desc = -1;
if(fd >= 0) {
close(fd);
DBG("[ usb closed %d ]\n", fd);
}
}
int usb_close(usb_handle *h)
{
int fd;
fd = h->desc;
h->desc = -1;
if(fd >= 0) {
close(fd);
DBG("[ usb closed %d ]\n", fd);
}
return 0;
}
usb_handle *usb_open(ifc_match_func callback)
{
return find_usb_device("/dev/bus/usb", callback);
}