sysfs.c

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#define remove_power_attributes(dev)	do {} while (0)

#endif	/* CONFIG_USB_SUSPEND */


/* Descriptor fields */
#define usb_descriptor_attr_le16(field, format_string)			\
static ssize_t								\
show_##field(struct device *dev, struct device_attribute *attr,	\
		char *buf)						\
{									\
	struct usb_device *udev;					\
									\
	udev = to_usb_device(dev);					\
	return sprintf(buf, format_string, 				\
			le16_to_cpu(udev->descriptor.field));		\
}									\
static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);

usb_descriptor_attr_le16(idVendor, "%04x\n")
usb_descriptor_attr_le16(idProduct, "%04x\n")
usb_descriptor_attr_le16(bcdDevice, "%04x\n")

#define usb_descriptor_attr(field, format_string)			\
static ssize_t								\
show_##field(struct device *dev, struct device_attribute *attr,	\
		char *buf)						\
{									\
	struct usb_device *udev;					\
									\
	udev = to_usb_device(dev);					\
	return sprintf(buf, format_string, udev->descriptor.field);	\
}									\
static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);

usb_descriptor_attr(bDeviceClass, "%02x\n")
usb_descriptor_attr(bDeviceSubClass, "%02x\n")
usb_descriptor_attr(bDeviceProtocol, "%02x\n")
usb_descriptor_attr(bNumConfigurations, "%d\n")
usb_descriptor_attr(bMaxPacketSize0, "%d\n")



/* show if the device is authorized (1) or not (0) */
static ssize_t usb_dev_authorized_show(struct device *dev,
				       struct device_attribute *attr,
				       char *buf)
{
	struct usb_device *usb_dev = to_usb_device(dev);
	return snprintf(buf, PAGE_SIZE, "%u\n", usb_dev->authorized);
}


/*
 * Authorize a device to be used in the system
 *
 * Writing a 0 deauthorizes the device, writing a 1 authorizes it.
 */
static ssize_t usb_dev_authorized_store(struct device *dev,
					struct device_attribute *attr,
					const char *buf, size_t size)
{
	ssize_t result;
	struct usb_device *usb_dev = to_usb_device(dev);
	unsigned val;
	result = sscanf(buf, "%u\n", &val);
	if (result != 1)
		result = -EINVAL;
	else if (val == 0)
		result = usb_deauthorize_device(usb_dev);
	else
		result = usb_authorize_device(usb_dev);
	return result < 0? result : size;
}

static DEVICE_ATTR(authorized, 0644,
	    usb_dev_authorized_show, usb_dev_authorized_store);


static struct attribute *dev_attrs[] = {
	/* current configuration's attributes */
	&dev_attr_configuration.attr,
	&dev_attr_bNumInterfaces.attr,
	&dev_attr_bConfigurationValue.attr,
	&dev_attr_bmAttributes.attr,
	&dev_attr_bMaxPower.attr,
	&dev_attr_urbnum.attr,
	/* device attributes */
	&dev_attr_idVendor.attr,
	&dev_attr_idProduct.attr,
	&dev_attr_bcdDevice.attr,
	&dev_attr_bDeviceClass.attr,
	&dev_attr_bDeviceSubClass.attr,
	&dev_attr_bDeviceProtocol.attr,
	&dev_attr_bNumConfigurations.attr,
	&dev_attr_bMaxPacketSize0.attr,
	&dev_attr_speed.attr,
	&dev_attr_busnum.attr,
	&dev_attr_devnum.attr,
	&dev_attr_version.attr,
	&dev_attr_maxchild.attr,
	&dev_attr_quirks.attr,
	&dev_attr_authorized.attr,
	NULL,
};
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;
	int retval;

	retval = sysfs_create_group(&dev->kobj, &dev_attr_grp);
	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;

	retval = add_power_attributes(dev);
	if (retval)
		goto error;

	if (udev->manufacturer) {
		retval = device_create_file(dev, &dev_attr_manufacturer);
		if (retval)
			goto error;
	}
	if (udev->product) {
		retval = device_create_file(dev, &dev_attr_product);
		if (retval)
			goto error;
	}
	if (udev->serial) {
		retval = device_create_file(dev, &dev_attr_serial);
		if (retval)
			goto error;
	}
	retval = usb_create_ep_files(dev, &udev->ep0, udev);
	if (retval)
		goto error;
	return 0;
error:
	usb_remove_sysfs_dev_files(udev);
	return retval;
}

void usb_remove_sysfs_dev_files(struct usb_device *udev)
{
	struct device *dev = &udev->dev;

	usb_remove_ep_files(&udev->ep0);
	device_remove_file(dev, &dev_attr_manufacturer);
	device_remove_file(dev, &dev_attr_product);
	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);
}

/* Interface Accociation Descriptor fields */
#define usb_intf_assoc_attr(field, format_string)			\
static ssize_t								\
show_iad_##field (struct device *dev, struct device_attribute *attr,	\
		char *buf)						\
{									\
	struct usb_interface *intf = to_usb_interface (dev);		\
									\
	return sprintf (buf, format_string,				\
			intf->intf_assoc->field); 		\
}									\
static DEVICE_ATTR(iad_##field, S_IRUGO, show_iad_##field, NULL);

usb_intf_assoc_attr (bFirstInterface, "%02x\n")
usb_intf_assoc_attr (bInterfaceCount, "%02d\n")
usb_intf_assoc_attr (bFunctionClass, "%02x\n")
usb_intf_assoc_attr (bFunctionSubClass, "%02x\n")
usb_intf_assoc_attr (bFunctionProtocol, "%02x\n")

/* Interface fields */
#define usb_intf_attr(field, format_string)				\
static ssize_t								\
show_##field(struct device *dev, struct device_attribute *attr,	\
		char *buf)						\
{									\
	struct usb_interface *intf = to_usb_interface(dev);		\
									\
	return sprintf(buf, format_string,				\
			intf->cur_altsetting->desc.field); 		\
}									\
static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);

usb_intf_attr(bInterfaceNumber, "%02x\n")
usb_intf_attr(bAlternateSetting, "%2d\n")
usb_intf_attr(bNumEndpoints, "%02x\n")
usb_intf_attr(bInterfaceClass, "%02x\n")
usb_intf_attr(bInterfaceSubClass, "%02x\n")
usb_intf_attr(bInterfaceProtocol, "%02x\n")

static ssize_t show_interface_string(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct usb_interface *intf;
	struct usb_device *udev;
	int len;

	intf = to_usb_interface(dev);
	udev = interface_to_usbdev(intf);
	len = snprintf(buf, 256, "%s", intf->cur_altsetting->string);
	if (len < 0)
		return 0;
	buf[len] = '\n';
	buf[len+1] = 0;
	return len+1;
}
static DEVICE_ATTR(interface, S_IRUGO, show_interface_string, NULL);

static ssize_t show_modalias(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct usb_interface *intf;
	struct usb_device *udev;
	struct usb_host_interface *alt;

	intf = to_usb_interface(dev);
	udev = interface_to_usbdev(intf);
	alt = intf->cur_altsetting;

	return sprintf(buf, "usb:v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02X"
			"ic%02Xisc%02Xip%02X\n",
			le16_to_cpu(udev->descriptor.idVendor),
			le16_to_cpu(udev->descriptor.idProduct),
			le16_to_cpu(udev->descriptor.bcdDevice),
			udev->descriptor.bDeviceClass,
			udev->descriptor.bDeviceSubClass,
			udev->descriptor.bDeviceProtocol,
			alt->desc.bInterfaceClass,
			alt->desc.bInterfaceSubClass,
			alt->desc.bInterfaceProtocol);
}
static DEVICE_ATTR(modalias, S_IRUGO, show_modalias, NULL);

static struct attribute *intf_assoc_attrs[] = {
	&dev_attr_iad_bFirstInterface.attr,
	&dev_attr_iad_bInterfaceCount.attr,
	&dev_attr_iad_bFunctionClass.attr,
	&dev_attr_iad_bFunctionSubClass.attr,
	&dev_attr_iad_bFunctionProtocol.attr,
	NULL,
};
static struct attribute_group intf_assoc_attr_grp = {
	.attrs = intf_assoc_attrs,
};

static struct attribute *intf_attrs[] = {
	&dev_attr_bInterfaceNumber.attr,
	&dev_attr_bAlternateSetting.attr,
	&dev_attr_bNumEndpoints.attr,
	&dev_attr_bInterfaceClass.attr,
	&dev_attr_bInterfaceSubClass.attr,
	&dev_attr_bInterfaceProtocol.attr,
	&dev_attr_modalias.attr,
	NULL,
};
static struct attribute_group intf_attr_grp = {
	.attrs = intf_attrs,
};

static inline void usb_create_intf_ep_files(struct usb_interface *intf,
		struct usb_device *udev)
{
	struct usb_host_interface *iface_desc;
	int i;

	iface_desc = intf->cur_altsetting;
	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i)
		usb_create_ep_files(&intf->dev, &iface_desc->endpoint[i],
				udev);
}

static inline void usb_remove_intf_ep_files(struct usb_interface *intf)
{
	struct usb_host_interface *iface_desc;
	int i;

	iface_desc = intf->cur_altsetting;
	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i)
		usb_remove_ep_files(&iface_desc->endpoint[i]);
}

int usb_create_sysfs_intf_files(struct usb_interface *intf)
{
	struct device *dev = &intf->dev;
	struct usb_device *udev = interface_to_usbdev(intf);
	struct usb_host_interface *alt = intf->cur_altsetting;
	int retval;

	if (intf->sysfs_files_created)
		return 0;
	retval = sysfs_create_group(&dev->kobj, &intf_attr_grp);
	if (retval)
		return retval;

	if (alt->string == NULL)
		alt->string = usb_cache_string(udev, alt->desc.iInterface);
	if (alt->string)
		retval = device_create_file(dev, &dev_attr_interface);
	if (intf->intf_assoc)
		retval = sysfs_create_group(&dev->kobj, &intf_assoc_attr_grp);
	usb_create_intf_ep_files(intf, udev);
	intf->sysfs_files_created = 1;
	return 0;
}

void usb_remove_sysfs_intf_files(struct usb_interface *intf)
{
	struct device *dev = &intf->dev;

	if (!intf->sysfs_files_created)
		return;
	usb_remove_intf_ep_files(intf);
	device_remove_file(dev, &dev_attr_interface);
	sysfs_remove_group(&dev->kobj, &intf_attr_grp);
	sysfs_remove_group(&intf->dev.kobj, &intf_assoc_attr_grp);
	intf->sysfs_files_created = 0;
}