Hash :
7ffb1614
Author :
Date :
2014-02-06T09:52:46
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/*
* Copyright (c) 2011 Martin Pieuchot <mpi@openbsd.org>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <sys/time.h>
#include <sys/types.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <dev/usb/usb.h>
#include "libusb.h"
#include "libusbi.h"
struct device_priv {
char devnode[16];
int fd;
unsigned char *cdesc; /* active config descriptor */
usb_device_descriptor_t ddesc; /* usb device descriptor */
};
struct handle_priv {
int pipe[2]; /* for event notification */
int endpoints[USB_MAX_ENDPOINTS];
};
/*
* Backend functions
*/
static int obsd_get_device_list(struct libusb_context *,
struct discovered_devs **);
static int obsd_open(struct libusb_device_handle *);
static void obsd_close(struct libusb_device_handle *);
static int obsd_get_device_descriptor(struct libusb_device *, unsigned char *,
int *);
static int obsd_get_active_config_descriptor(struct libusb_device *,
unsigned char *, size_t, int *);
static int obsd_get_config_descriptor(struct libusb_device *, uint8_t,
unsigned char *, size_t, int *);
static int obsd_get_configuration(struct libusb_device_handle *, int *);
static int obsd_set_configuration(struct libusb_device_handle *, int);
static int obsd_claim_interface(struct libusb_device_handle *, int);
static int obsd_release_interface(struct libusb_device_handle *, int);
static int obsd_set_interface_altsetting(struct libusb_device_handle *, int,
int);
static int obsd_clear_halt(struct libusb_device_handle *, unsigned char);
static int obsd_reset_device(struct libusb_device_handle *);
static void obsd_destroy_device(struct libusb_device *);
static int obsd_submit_transfer(struct usbi_transfer *);
static int obsd_cancel_transfer(struct usbi_transfer *);
static void obsd_clear_transfer_priv(struct usbi_transfer *);
static int obsd_handle_events(struct libusb_context *ctx, struct pollfd *,
nfds_t, int);
static int obsd_clock_gettime(int, struct timespec *);
/*
* Private functions
*/
static int _errno_to_libusb(int);
static int _cache_active_config_descriptor(struct libusb_device *, int);
static int _sync_control_transfer(struct usbi_transfer *);
static int _sync_gen_transfer(struct usbi_transfer *);
static int _access_endpoint(struct libusb_transfer *);
const struct usbi_os_backend openbsd_backend = {
"Synchronous OpenBSD backend",
NULL, /* init() */
NULL, /* exit() */
obsd_get_device_list,
obsd_open,
obsd_close,
obsd_get_device_descriptor,
obsd_get_active_config_descriptor,
obsd_get_config_descriptor,
obsd_get_configuration,
obsd_set_configuration,
obsd_claim_interface,
obsd_release_interface,
obsd_set_interface_altsetting,
obsd_clear_halt,
obsd_reset_device,
NULL, /* kernel_driver_active() */
NULL, /* detach_kernel_driver() */
NULL, /* attach_kernel_driver() */
obsd_destroy_device,
obsd_submit_transfer,
obsd_cancel_transfer,
obsd_clear_transfer_priv,
obsd_handle_events,
obsd_clock_gettime,
sizeof(struct device_priv),
sizeof(struct handle_priv),
0, /* transfer_priv_size */
0, /* add_iso_packet_size */
};
int
obsd_get_device_list(struct libusb_context * ctx,
struct discovered_devs **discdevs)
{
struct libusb_device *dev;
struct device_priv *dpriv;
struct usb_device_info di;
unsigned long session_id;
char devnode[16];
int fd, err, i;
usbi_dbg("");
/* Only ugen(4) is supported */
for (i = 0; i < USB_MAX_DEVICES; i++) {
/* Control endpoint is always .00 */
snprintf(devnode, sizeof(devnode), "/dev/ugen%d.00", i);
if ((fd = open(devnode, O_RDONLY)) < 0) {
if (errno != ENOENT && errno != ENXIO)
usbi_err(ctx, "could not open %s", devnode);
continue;
}
if (ioctl(fd, USB_GET_DEVICEINFO, &di) < 0)
continue;
session_id = (di.udi_bus << 8 | di.udi_addr);
dev = usbi_get_device_by_session_id(ctx, session_id);
if (dev == NULL) {
dev = usbi_alloc_device(ctx, session_id);
if (dev == NULL)
return (LIBUSB_ERROR_NO_MEM);
dev->bus_number = di.udi_bus;
dev->device_address = di.udi_addr;
dev->speed = di.udi_speed;
dpriv = (struct device_priv *)dev->os_priv;
strlcpy(dpriv->devnode, devnode, sizeof(devnode));
dpriv->fd = -1;
if (ioctl(fd, USB_GET_DEVICE_DESC, &dpriv->ddesc) < 0) {
err = errno;
goto error;
}
dpriv->cdesc = NULL;
if (_cache_active_config_descriptor(dev, fd)) {
err = errno;
goto error;
}
if ((err = usbi_sanitize_device(dev)))
goto error;
}
close(fd);
if (discovered_devs_append(*discdevs, dev) == NULL)
return (LIBUSB_ERROR_NO_MEM);
}
return (LIBUSB_SUCCESS);
error:
close(fd);
libusb_unref_device(dev);
return _errno_to_libusb(err);
}
int
obsd_open(struct libusb_device_handle *handle)
{
struct handle_priv *hpriv = (struct handle_priv *)handle->os_priv;
struct device_priv *dpriv = (struct device_priv *)handle->dev->os_priv;
dpriv->fd = open(dpriv->devnode, O_RDWR);
if (dpriv->fd < 0) {
dpriv->fd = open(dpriv->devnode, O_RDONLY);
if (dpriv->fd < 0)
return _errno_to_libusb(errno);
}
usbi_dbg("open %s: fd %d", dpriv->devnode, dpriv->fd);
if (pipe(hpriv->pipe) < 0)
return _errno_to_libusb(errno);
return usbi_add_pollfd(HANDLE_CTX(handle), hpriv->pipe[0], POLLIN);
}
void
obsd_close(struct libusb_device_handle *handle)
{
struct handle_priv *hpriv = (struct handle_priv *)handle->os_priv;
struct device_priv *dpriv = (struct device_priv *)handle->dev->os_priv;
usbi_dbg("close: fd %d", dpriv->fd);
close(dpriv->fd);
dpriv->fd = -1;
usbi_remove_pollfd(HANDLE_CTX(handle), hpriv->pipe[0]);
close(hpriv->pipe[0]);
close(hpriv->pipe[1]);
}
int
obsd_get_device_descriptor(struct libusb_device *dev, unsigned char *buf,
int *host_endian)
{
struct device_priv *dpriv = (struct device_priv *)dev->os_priv;
usbi_dbg("");
memcpy(buf, &dpriv->ddesc, DEVICE_DESC_LENGTH);
*host_endian = 0;
return (LIBUSB_SUCCESS);
}
int
obsd_get_active_config_descriptor(struct libusb_device *dev,
unsigned char *buf, size_t len, int *host_endian)
{
struct device_priv *dpriv = (struct device_priv *)dev->os_priv;
usb_config_descriptor_t *ucd;
ucd = (usb_config_descriptor_t *) dpriv->cdesc;
len = MIN(len, UGETW(ucd->wTotalLength));
usbi_dbg("len %d", len);
memcpy(buf, dpriv->cdesc, len);
*host_endian = 0;
return (LIBUSB_SUCCESS);
}
int
obsd_get_config_descriptor(struct libusb_device *dev, uint8_t idx,
unsigned char *buf, size_t len, int *host_endian)
{
struct device_priv *dpriv = (struct device_priv *)dev->os_priv;
struct usb_full_desc ufd;
int fd, err;
usbi_dbg("index %d, len %d", idx, len);
/* A config descriptor may be requested before opening the device */
if (dpriv->fd >= 0) {
fd = dpriv->fd;
} else {
fd = open(dpriv->devnode, O_RDONLY);
if (fd < 0)
return _errno_to_libusb(errno);
}
ufd.ufd_config_index = idx;
ufd.ufd_size = len;
ufd.ufd_data = buf;
if ((ioctl(fd, USB_GET_FULL_DESC, &ufd)) < 0) {
err = errno;
if (dpriv->fd < 0)
close(fd);
return _errno_to_libusb(err);
}
if (dpriv->fd < 0)
close(fd);
*host_endian = 0;
return (LIBUSB_SUCCESS);
}
int
obsd_get_configuration(struct libusb_device_handle *handle, int *config)
{
struct device_priv *dpriv = (struct device_priv *)handle->dev->os_priv;
usbi_dbg("");
if (ioctl(dpriv->fd, USB_GET_CONFIG, config) < 0)
return _errno_to_libusb(errno);
usbi_dbg("configuration %d", *config);
return (LIBUSB_SUCCESS);
}
int
obsd_set_configuration(struct libusb_device_handle *handle, int config)
{
struct device_priv *dpriv = (struct device_priv *)handle->dev->os_priv;
usbi_dbg("configuration %d", config);
if (ioctl(dpriv->fd, USB_SET_CONFIG, &config) < 0)
return _errno_to_libusb(errno);
return _cache_active_config_descriptor(handle->dev, dpriv->fd);
}
int
obsd_claim_interface(struct libusb_device_handle *handle, int iface)
{
struct handle_priv *hpriv = (struct handle_priv *)handle->os_priv;
int i;
for (i = 0; i < USB_MAX_ENDPOINTS; i++)
hpriv->endpoints[i] = -1;
return (LIBUSB_SUCCESS);
}
int
obsd_release_interface(struct libusb_device_handle *handle, int iface)
{
struct handle_priv *hpriv = (struct handle_priv *)handle->os_priv;
int i;
for (i = 0; i < USB_MAX_ENDPOINTS; i++)
if (hpriv->endpoints[i] >= 0)
close(hpriv->endpoints[i]);
return (LIBUSB_SUCCESS);
}
int
obsd_set_interface_altsetting(struct libusb_device_handle *handle, int iface,
int altsetting)
{
struct device_priv *dpriv = (struct device_priv *)handle->dev->os_priv;
struct usb_alt_interface intf;
usbi_dbg("iface %d, setting %d", iface, altsetting);
memset(&intf, 0, sizeof(intf));
intf.uai_interface_index = iface;
intf.uai_alt_no = altsetting;
if (ioctl(dpriv->fd, USB_SET_ALTINTERFACE, &intf) < 0)
return _errno_to_libusb(errno);
return (LIBUSB_SUCCESS);
}
int
obsd_clear_halt(struct libusb_device_handle *handle, unsigned char endpoint)
{
struct device_priv *dpriv = (struct device_priv *)handle->dev->os_priv;
struct usb_ctl_request req;
usbi_dbg("");
req.ucr_request.bmRequestType = UT_WRITE_ENDPOINT;
req.ucr_request.bRequest = UR_CLEAR_FEATURE;
USETW(req.ucr_request.wValue, UF_ENDPOINT_HALT);
USETW(req.ucr_request.wIndex, endpoint);
USETW(req.ucr_request.wLength, 0);
if (ioctl(dpriv->fd, USB_DO_REQUEST, &req) < 0)
return _errno_to_libusb(errno);
return (LIBUSB_SUCCESS);
}
int
obsd_reset_device(struct libusb_device_handle *handle)
{
usbi_dbg("");
return (LIBUSB_ERROR_NOT_SUPPORTED);
}
void
obsd_destroy_device(struct libusb_device *dev)
{
struct device_priv *dpriv = (struct device_priv *)dev->os_priv;
usbi_dbg("");
free(dpriv->cdesc);
}
int
obsd_submit_transfer(struct usbi_transfer *itransfer)
{
struct libusb_transfer *transfer;
struct handle_priv *hpriv;
int err = 0;
usbi_dbg("");
transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
hpriv = (struct handle_priv *)transfer->dev_handle->os_priv;
switch (transfer->type) {
case LIBUSB_TRANSFER_TYPE_CONTROL:
err = _sync_control_transfer(itransfer);
break;
case LIBUSB_TRANSFER_TYPE_ISOCHRONOUS:
if (IS_XFEROUT(transfer)) {
/* Isochronous write is not supported */
err = LIBUSB_ERROR_NOT_SUPPORTED;
break;
}
err = _sync_gen_transfer(itransfer);
break;
case LIBUSB_TRANSFER_TYPE_BULK:
case LIBUSB_TRANSFER_TYPE_INTERRUPT:
if (IS_XFEROUT(transfer) &&
transfer->flags & LIBUSB_TRANSFER_ADD_ZERO_PACKET) {
err = LIBUSB_ERROR_NOT_SUPPORTED;
break;
}
err = _sync_gen_transfer(itransfer);
break;
}
if (err)
return (err);
if (write(hpriv->pipe[1], &itransfer, sizeof(itransfer)) < 0)
return _errno_to_libusb(errno);
return (LIBUSB_SUCCESS);
}
int
obsd_cancel_transfer(struct usbi_transfer *itransfer)
{
usbi_dbg("");
return (LIBUSB_ERROR_NOT_SUPPORTED);
}
void
obsd_clear_transfer_priv(struct usbi_transfer *itransfer)
{
usbi_dbg("");
/* Nothing to do */
}
int
obsd_handle_events(struct libusb_context *ctx, struct pollfd *fds, nfds_t nfds,
int num_ready)
{
struct libusb_device_handle *handle;
struct handle_priv *hpriv = NULL;
struct usbi_transfer *itransfer;
struct pollfd *pollfd;
int i, err = 0;
usbi_dbg("");
pthread_mutex_lock(&ctx->open_devs_lock);
for (i = 0; i < nfds && num_ready > 0; i++) {
pollfd = &fds[i];
if (!pollfd->revents)
continue;
hpriv = NULL;
num_ready--;
list_for_each_entry(handle, &ctx->open_devs, list,
struct libusb_device_handle) {
hpriv = (struct handle_priv *)handle->os_priv;
if (hpriv->pipe[0] == pollfd->fd)
break;
hpriv = NULL;
}
if (NULL == hpriv) {
usbi_dbg("fd %d is not an event pipe!", pollfd->fd);
err = ENOENT;
break;
}
if (pollfd->revents & POLLERR) {
usbi_remove_pollfd(HANDLE_CTX(handle), hpriv->pipe[0]);
usbi_handle_disconnect(handle);
continue;
}
if (read(hpriv->pipe[0], &itransfer, sizeof(itransfer)) < 0) {
err = errno;
break;
}
if ((err = usbi_handle_transfer_completion(itransfer,
LIBUSB_TRANSFER_COMPLETED)))
break;
}
pthread_mutex_unlock(&ctx->open_devs_lock);
if (err)
return _errno_to_libusb(err);
return (LIBUSB_SUCCESS);
}
int
obsd_clock_gettime(int clkid, struct timespec *tp)
{
usbi_dbg("clock %d", clkid);
if (clkid == USBI_CLOCK_REALTIME)
return clock_gettime(CLOCK_REALTIME, tp);
if (clkid == USBI_CLOCK_MONOTONIC)
return clock_gettime(CLOCK_MONOTONIC, tp);
return (LIBUSB_ERROR_INVALID_PARAM);
}
int
_errno_to_libusb(int err)
{
switch (err) {
case EIO:
return (LIBUSB_ERROR_IO);
case EACCES:
return (LIBUSB_ERROR_ACCESS);
case ENOENT:
return (LIBUSB_ERROR_NO_DEVICE);
case ENOMEM:
return (LIBUSB_ERROR_NO_MEM);
}
usbi_dbg("error: %s", strerror(err));
return (LIBUSB_ERROR_OTHER);
}
int
_cache_active_config_descriptor(struct libusb_device *dev, int fd)
{
struct device_priv *dpriv = (struct device_priv *)dev->os_priv;
struct usb_config_desc ucd;
struct usb_full_desc ufd;
unsigned char* buf;
int len;
usbi_dbg("fd %d", fd);
ucd.ucd_config_index = USB_CURRENT_CONFIG_INDEX;
if ((ioctl(fd, USB_GET_CONFIG_DESC, &ucd)) < 0)
return _errno_to_libusb(errno);
usbi_dbg("active bLength %d", ucd.ucd_desc.bLength);
len = UGETW(ucd.ucd_desc.wTotalLength);
buf = malloc(len);
if (buf == NULL)
return (LIBUSB_ERROR_NO_MEM);
ufd.ufd_config_index = ucd.ucd_config_index;
ufd.ufd_size = len;
ufd.ufd_data = buf;
usbi_dbg("index %d, len %d", ufd.ufd_config_index, len);
if ((ioctl(fd, USB_GET_FULL_DESC, &ufd)) < 0) {
free(buf);
return _errno_to_libusb(errno);
}
if (dpriv->cdesc)
free(dpriv->cdesc);
dpriv->cdesc = buf;
return (0);
}
int
_sync_control_transfer(struct usbi_transfer *itransfer)
{
struct libusb_transfer *transfer;
struct libusb_control_setup *setup;
struct device_priv *dpriv;
struct usb_ctl_request req;
transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
dpriv = (struct device_priv *)transfer->dev_handle->dev->os_priv;
setup = (struct libusb_control_setup *)transfer->buffer;
usbi_dbg("type %d request %d value %d index %d length %d timeout %d",
setup->bmRequestType, setup->bRequest,
libusb_le16_to_cpu(setup->wValue),
libusb_le16_to_cpu(setup->wIndex),
libusb_le16_to_cpu(setup->wLength), transfer->timeout);
req.ucr_request.bmRequestType = setup->bmRequestType;
req.ucr_request.bRequest = setup->bRequest;
/* Don't use USETW, libusb already deals with the endianness */
(*(uint16_t *)req.ucr_request.wValue) = setup->wValue;
(*(uint16_t *)req.ucr_request.wIndex) = setup->wIndex;
(*(uint16_t *)req.ucr_request.wLength) = setup->wLength;
req.ucr_data = transfer->buffer + LIBUSB_CONTROL_SETUP_SIZE;
if ((transfer->flags & LIBUSB_TRANSFER_SHORT_NOT_OK) == 0)
req.ucr_flags = USBD_SHORT_XFER_OK;
if ((ioctl(dpriv->fd, USB_SET_TIMEOUT, &transfer->timeout)) < 0)
return _errno_to_libusb(errno);
if ((ioctl(dpriv->fd, USB_DO_REQUEST, &req)) < 0)
return _errno_to_libusb(errno);
itransfer->transferred = req.ucr_actlen;
usbi_dbg("transferred %d", itransfer->transferred);
return (0);
}
int
_access_endpoint(struct libusb_transfer *transfer)
{
struct handle_priv *hpriv;
struct device_priv *dpriv;
char *s, devnode[16];
int fd, endpt;
mode_t mode;
hpriv = (struct handle_priv *)transfer->dev_handle->os_priv;
dpriv = (struct device_priv *)transfer->dev_handle->dev->os_priv;
endpt = UE_GET_ADDR(transfer->endpoint);
mode = IS_XFERIN(transfer) ? O_RDONLY : O_WRONLY;
usbi_dbg("endpoint %d mode %d", endpt, mode);
if (hpriv->endpoints[endpt] < 0) {
/* Pick the right node given the control one */
strlcpy(devnode, dpriv->devnode, sizeof(devnode));
s = strchr(devnode, '.');
snprintf(s, 4, ".%02d", endpt);
/* We may need to read/write to the same endpoint later. */
if (((fd = open(devnode, O_RDWR)) < 0) && (errno == ENXIO))
if ((fd = open(devnode, mode)) < 0)
return (-1);
hpriv->endpoints[endpt] = fd;
}
return (hpriv->endpoints[endpt]);
}
int
_sync_gen_transfer(struct usbi_transfer *itransfer)
{
struct libusb_transfer *transfer;
int fd, nr = 1;
transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
/*
* Bulk, Interrupt or Isochronous transfer depends on the
* endpoint and thus the node to open.
*/
if ((fd = _access_endpoint(transfer)) < 0)
return _errno_to_libusb(errno);
if ((ioctl(fd, USB_SET_TIMEOUT, &transfer->timeout)) < 0)
return _errno_to_libusb(errno);
if (IS_XFERIN(transfer)) {
if ((transfer->flags & LIBUSB_TRANSFER_SHORT_NOT_OK) == 0)
if ((ioctl(fd, USB_SET_SHORT_XFER, &nr)) < 0)
return _errno_to_libusb(errno);
nr = read(fd, transfer->buffer, transfer->length);
} else {
nr = write(fd, transfer->buffer, transfer->length);
}
if (nr < 0)
return _errno_to_libusb(errno);
itransfer->transferred = nr;
return (0);
}