diff options
Diffstat (limited to 'drivers/usb/core')
| -rw-r--r-- | drivers/usb/core/sysfs.c | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/drivers/usb/core/sysfs.c b/drivers/usb/core/sysfs.c index d47ae89154a..2ab222be8fd 100644 --- a/drivers/usb/core/sysfs.c +++ b/drivers/usb/core/sysfs.c @@ -441,6 +441,54 @@ static struct attribute_group dev_attr_grp = { .attrs = dev_attrs, }; +/* Binary descriptors */ + +static ssize_t +read_descriptors(struct kobject *kobj, struct bin_attribute *attr, + char *buf, loff_t off, size_t count) +{ + struct usb_device *udev = to_usb_device( + container_of(kobj, struct device, kobj)); + size_t nleft = count; + size_t srclen, n; + + usb_lock_device(udev); + + /* The binary attribute begins with the device descriptor */ + srclen = sizeof(struct usb_device_descriptor); + if (off < srclen) { + n = min_t(size_t, nleft, srclen - off); + memcpy(buf, off + (char *) &udev->descriptor, n); + nleft -= n; + buf += n; + off = 0; + } else { + off -= srclen; + } + + /* Then follows the raw descriptor entry for the current + * configuration (config plus subsidiary descriptors). + */ + if (udev->actconfig) { + int cfgno = udev->actconfig - udev->config; + + srclen = __le16_to_cpu(udev->actconfig->desc.wTotalLength); + if (off < srclen) { + n = min_t(size_t, nleft, srclen - off); + memcpy(buf, off + udev->rawdescriptors[cfgno], n); + nleft -= n; + } + } + usb_unlock_device(udev); + return count - nleft; +} + +static struct bin_attribute dev_bin_attr_descriptors = { + .attr = {.name = "descriptors", .mode = 0444}, + .read = read_descriptors, + .size = 18 + 65535, /* dev descr + max-size raw descriptor */ +}; + int usb_create_sysfs_dev_files(struct usb_device *udev) { struct device *dev = &udev->dev; @@ -450,6 +498,10 @@ int usb_create_sysfs_dev_files(struct usb_device *udev) if (retval) return retval; + retval = device_create_bin_file(dev, &dev_bin_attr_descriptors); + if (retval) + goto error; + retval = add_persist_attributes(dev); if (retval) goto error; @@ -492,6 +544,7 @@ void usb_remove_sysfs_dev_files(struct usb_device *udev) device_remove_file(dev, &dev_attr_serial); remove_power_attributes(dev); remove_persist_attributes(dev); + device_remove_bin_file(dev, &dev_bin_attr_descriptors); sysfs_remove_group(&dev->kobj, &dev_attr_grp); } |