Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted

Pull networking updates from Jakub Kicinski:
 "Core:

   - Add dedicated kmem_cache for typical/small skb->head, avoid having
     to access struct page at kfree time, and improve memory use.

   - Introduce sysctl to set default RPS configuration for new netdevs.

   - Define Netlink protocol specification format which can be used to
     describe messages used by each family and auto-generate parsers.
     Add tools for generating kernel data structures and uAPI headers.

   - Expose all net/core sysctls inside netns.

   - Remove 4s sleep in netpoll if carrier is instantly detected on
     boot.

   - Add configurable limit of MDB entries per port, and port-vlan.

   - Continue populating drop reasons throughout the stack.

   - Retire a handful of legacy Qdiscs and classifiers.

  Protocols:

   - Support IPv4 big TCP (TSO frames larger than 64kB).

   - Add IP_LOCAL_PORT_RANGE socket option, to control local port range
     on socket by socket basis.

   - Track and report in procfs number of MPTCP sockets used.

   - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
     manager.

   - IPv6: don't check net.ipv6.route.max_size and rely on garbage
     collection to free memory (similarly to IPv4).

   - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).

   - ICMP: add per-rate limit counters.

   - Add support for user scanning requests in ieee802154.

   - Remove static WEP support.

   - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
     reporting.

   - WiFi 7 EHT channel puncturing support (client & AP).

  BPF:

   - Add a rbtree data structure following the "next-gen data structure"
     precedent set by recently added linked list, that is, by using
     kfunc + kptr instead of adding a new BPF map type.

   - Expose XDP hints via kfuncs with initial support for RX hash and
     timestamp metadata.

   - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
     better support decap on GRE tunnel devices not operating in collect
     metadata.

   - Improve x86 JIT's codegen for PROBE_MEM runtime error checks.

   - Remove the need for trace_printk_lock for bpf_trace_printk and
     bpf_trace_vprintk helpers.

   - Extend libbpf's bpf_tracing.h support for tracing arguments of
     kprobes/uprobes and syscall as a special case.

   - Significantly reduce the search time for module symbols by
     livepatch and BPF.

   - Enable cpumasks to be used as kptrs, which is useful for tracing
     programs tracking which tasks end up running on which CPUs in
     different time intervals.

   - Add support for BPF trampoline on s390x and riscv64.

   - Add capability to export the XDP features supported by the NIC.

   - Add __bpf_kfunc tag for marking kernel functions as kfuncs.

   - Add cgroup.memory=nobpf kernel parameter option to disable BPF
     memory accounting for container environments.

  Netfilter:

   - Remove the CLUSTERIP target. It has been marked as obsolete for
     years, and we still have WARN splats wrt races of the out-of-band
     /proc interface installed by this target.

   - Add 'destroy' commands to nf_tables. They are identical to the
     existing 'delete' commands, but do not return an error if the
     referenced object (set, chain, rule...) did not exist.

  Driver API:

   - Improve cpumask_local_spread() locality to help NICs set the right
     IRQ affinity on AMD platforms.

   - Separate C22 and C45 MDIO bus transactions more clearly.

   - Introduce new DCB table to control DSCP rewrite on egress.

   - Support configuration of Physical Layer Collision Avoidance (PLCA)
     Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
     shared medium Ethernet.

   - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
     preemption of low priority frames by high priority frames.

   - Add support for controlling MACSec offload using netlink SET.

   - Rework devlink instance refcounts to allow registration and
     de-registration under the instance lock. Split the code into
     multiple files, drop some of the unnecessarily granular locks and
     factor out common parts of netlink operation handling.

   - Add TX frame aggregation parameters (for USB drivers).

   - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
     messages with notifications for debug.

   - Allow offloading of UDP NEW connections via act_ct.

   - Add support for per action HW stats in TC.

   - Support hardware miss to TC action (continue processing in SW from
     a specific point in the action chain).

   - Warn if old Wireless Extension user space interface is used with
     modern cfg80211/mac80211 drivers. Do not support Wireless
     Extensions for Wi-Fi 7 devices at all. Everyone should switch to
     using nl80211 interface instead.

   - Improve the CAN bit timing configuration. Use extack to return
     error messages directly to user space, update the SJW handling,
     including the definition of a new default value that will benefit
     CAN-FD controllers, by increasing their oscillator tolerance.

  New hardware / drivers:

   - Ethernet:
      - nVidia BlueField-3 support (control traffic driver)
      - Ethernet support for imx93 SoCs
      - Motorcomm yt8531 gigabit Ethernet PHY
      - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
      - Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
      - Amlogic gxl MDIO mux

   - WiFi:
      - RealTek RTL8188EU (rtl8xxxu)
      - Qualcomm Wi-Fi 7 devices (ath12k)

   - CAN:
      - Renesas R-Car V4H

  Drivers:

   - Bluetooth:
      - Set Per Platform Antenna Gain (PPAG) for Intel controllers.

   - Ethernet NICs:
      - Intel (1G, igc):
         - support TSN / Qbv / packet scheduling features of i226 model
      - Intel (100G, ice):
         - use GNSS subsystem instead of TTY
         - multi-buffer XDP support
         - extend support for GPIO pins to E823 devices
      - nVidia/Mellanox:
         - update the shared buffer configuration on PFC commands
         - implement PTP adjphase function for HW offset control
         - TC support for Geneve and GRE with VF tunnel offload
         - more efficient crypto key management method
         - multi-port eswitch support
      - Netronome/Corigine:
         - add DCB IEEE support
         - support IPsec offloading for NFP3800
      - Freescale/NXP (enetc):
         - support XDP_REDIRECT for XDP non-linear buffers
         - improve reconfig, avoid link flap and waiting for idle
         - support MAC Merge layer
      - Other NICs:
         - sfc/ef100: add basic devlink support for ef100
         - ionic: rx_push mode operation (writing descriptors via MMIO)
         - bnxt: use the auxiliary bus abstraction for RDMA
         - r8169: disable ASPM and reset bus in case of tx timeout
         - cpsw: support QSGMII mode for J721e CPSW9G
         - cpts: support pulse-per-second output
         - ngbe: add an mdio bus driver
         - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
         - r8152: handle devices with FW with NCM support
         - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
         - virtio-net: support multi buffer XDP
         - virtio/vsock: replace virtio_vsock_pkt with sk_buff
         - tsnep: XDP support

   - Ethernet high-speed switches:
      - nVidia/Mellanox (mlxsw):
         - add support for latency TLV (in FW control messages)
      - Microchip (sparx5):
         - separate explicit and implicit traffic forwarding rules, make
           the implicit rules always active
         - add support for egress DSCP rewrite
         - IS0 VCAP support (Ingress Classification)
         - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
           etc.)
         - ES2 VCAP support (Egress Access Control)
         - support for Per-Stream Filtering and Policing (802.1Q,
           8.6.5.1)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - add MAB (port auth) offload support
         - enable PTP receive for mv88e6390
      - NXP (ocelot):
         - support MAC Merge layer
         - support for the the vsc7512 internal copper phys
      - Microchip:
         - lan9303: convert to PHYLINK
         - lan966x: support TC flower filter statistics
         - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
         - lan937x: support Credit Based Shaper configuration
         - ksz9477: support Energy Efficient Ethernet
      - other:
         - qca8k: convert to regmap read/write API, use bulk operations
         - rswitch: Improve TX timestamp accuracy

   - Intel WiFi (iwlwifi):
      - EHT (Wi-Fi 7) rate reporting
      - STEP equalizer support: transfer some STEP (connection to radio
        on platforms with integrated wifi) related parameters from the
        BIOS to the firmware.

   - Qualcomm 802.11ax WiFi (ath11k):
      - IPQ5018 support
      - Fine Timing Measurement (FTM) responder role support
      - channel 177 support

   - MediaTek WiFi (mt76):
      - per-PHY LED support
      - mt7996: EHT (Wi-Fi 7) support
      - Wireless Ethernet Dispatch (WED) reset support
      - switch to using page pool allocator

   - RealTek WiFi (rtw89):
      - support new version of Bluetooth co-existance

   - Mobile:
      - rmnet: support TX aggregation"

* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
  page_pool: add a comment explaining the fragment counter usage
  net: ethtool: fix __ethtool_dev_mm_supported() implementation
  ethtool: pse-pd: Fix double word in comments
  xsk: add linux/vmalloc.h to xsk.c
  sefltests: netdevsim: wait for devlink instance after netns removal
  selftest: fib_tests: Always cleanup before exit
  net/mlx5e: Align IPsec ASO result memory to be as required by hardware
  net/mlx5e: TC, Set CT miss to the specific ct action instance
  net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
  net/mlx5: Refactor tc miss handling to a single function
  net/mlx5: Kconfig: Make tc offload depend on tc skb extension
  net/sched: flower: Support hardware miss to tc action
  net/sched: flower: Move filter handle initialization earlier
  net/sched: cls_api: Support hardware miss to tc action
  net/sched: Rename user cookie and act cookie
  sfc: fix builds without CONFIG_RTC_LIB
  sfc: clean up some inconsistent indentings
  net/mlx4_en: Introduce flexible array to silence overflow warning
  net: lan966x: Fix possible deadlock inside PTP
  net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
  ...

1 files changed, 530 insertions, 0 deletions

diff --git a/drivers/usb/misc/yurex.c b/drivers/usb/misc/yurex.c
new file mode 100644
index 000000000..c640f98d2
--- /dev/null
+++ b/drivers/usb/misc/yurex.c
@@ -0,0 +1,530 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for Meywa-Denki & KAYAC YUREX
+ *
+ * Copyright (C) 2010 Tomoki Sekiyama (tomoki.sekiyama@gmail.com)
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/kref.h>
+#include <linux/mutex.h>
+#include <linux/uaccess.h>
+#include <linux/usb.h>
+#include <linux/hid.h>
+
+#define DRIVER_AUTHOR "Tomoki Sekiyama"
+#define DRIVER_DESC "Driver for Meywa-Denki & KAYAC YUREX"
+
+#define YUREX_VENDOR_ID		0x0c45
+#define YUREX_PRODUCT_ID	0x1010
+
+#define CMD_ACK		'!'
+#define CMD_ANIMATE	'A'
+#define CMD_COUNT	'C'
+#define CMD_LED		'L'
+#define CMD_READ	'R'
+#define CMD_SET		'S'
+#define CMD_VERSION	'V'
+#define CMD_EOF		0x0d
+#define CMD_PADDING	0xff
+
+#define YUREX_BUF_SIZE		8
+#define YUREX_WRITE_TIMEOUT	(HZ*2)
+
+/* table of devices that work with this driver */
+static struct usb_device_id yurex_table[] = {
+	{ USB_DEVICE(YUREX_VENDOR_ID, YUREX_PRODUCT_ID) },
+	{ }					/* Terminating entry */
+};
+MODULE_DEVICE_TABLE(usb, yurex_table);
+
+#ifdef CONFIG_USB_DYNAMIC_MINORS
+#define YUREX_MINOR_BASE	0
+#else
+#define YUREX_MINOR_BASE	192
+#endif
+
+/* Structure to hold all of our device specific stuff */
+struct usb_yurex {
+	struct usb_device	*udev;
+	struct usb_interface	*interface;
+	__u8			int_in_endpointAddr;
+	struct urb		*urb;		/* URB for interrupt in */
+	unsigned char           *int_buffer;	/* buffer for intterupt in */
+	struct urb		*cntl_urb;	/* URB for control msg */
+	struct usb_ctrlrequest	*cntl_req;	/* req for control msg */
+	unsigned char		*cntl_buffer;	/* buffer for control msg */
+
+	struct kref		kref;
+	struct mutex		io_mutex;
+	unsigned long		disconnected:1;
+	struct fasync_struct	*async_queue;
+	wait_queue_head_t	waitq;
+
+	spinlock_t		lock;
+	__s64			bbu;		/* BBU from device */
+};
+#define to_yurex_dev(d) container_of(d, struct usb_yurex, kref)
+
+static struct usb_driver yurex_driver;
+static const struct file_operations yurex_fops;
+
+
+static void yurex_control_callback(struct urb *urb)
+{
+	struct usb_yurex *dev = urb->context;
+	int status = urb->status;
+
+	if (status) {
+		dev_err(&urb->dev->dev, "%s - control failed: %d\n",
+			__func__, status);
+		wake_up_interruptible(&dev->waitq);
+		return;
+	}
+	/* on success, sender woken up by CMD_ACK int in, or timeout */
+}
+
+static void yurex_delete(struct kref *kref)
+{
+	struct usb_yurex *dev = to_yurex_dev(kref);
+
+	dev_dbg(&dev->interface->dev, "%s\n", __func__);
+
+	if (dev->cntl_urb) {
+		usb_kill_urb(dev->cntl_urb);
+		kfree(dev->cntl_req);
+		usb_free_coherent(dev->udev, YUREX_BUF_SIZE,
+				dev->cntl_buffer, dev->cntl_urb->transfer_dma);
+		usb_free_urb(dev->cntl_urb);
+	}
+	if (dev->urb) {
+		usb_kill_urb(dev->urb);
+		usb_free_coherent(dev->udev, YUREX_BUF_SIZE,
+				dev->int_buffer, dev->urb->transfer_dma);
+		usb_free_urb(dev->urb);
+	}
+	usb_put_intf(dev->interface);
+	usb_put_dev(dev->udev);
+	kfree(dev);
+}
+
+/*
+ * usb class driver info in order to get a minor number from the usb core,
+ * and to have the device registered with the driver core
+ */
+static struct usb_class_driver yurex_class = {
+	.name =		"yurex%d",
+	.fops =		&yurex_fops,
+	.minor_base =	YUREX_MINOR_BASE,
+};
+
+static void yurex_interrupt(struct urb *urb)
+{
+	struct usb_yurex *dev = urb->context;
+	unsigned char *buf = dev->int_buffer;
+	int status = urb->status;
+	unsigned long flags;
+	int retval, i;
+
+	switch (status) {
+	case 0: /*success*/
+		break;
+	/* The device is terminated or messed up, give up */
+	case -EOVERFLOW:
+		dev_err(&dev->interface->dev,
+			"%s - overflow with length %d, actual length is %d\n",
+			__func__, YUREX_BUF_SIZE, dev->urb->actual_length);
+		return;
+	case -ECONNRESET:
+	case -ENOENT:
+	case -ESHUTDOWN:
+	case -EILSEQ:
+	case -EPROTO:
+	case -ETIME:
+		return;
+	default:
+		dev_err(&dev->interface->dev,
+			"%s - unknown status received: %d\n", __func__, status);
+		return;
+	}
+
+	/* handle received message */
+	switch (buf[0]) {
+	case CMD_COUNT:
+	case CMD_READ:
+		if (buf[6] == CMD_EOF) {
+			spin_lock_irqsave(&dev->lock, flags);
+			dev->bbu = 0;
+			for (i = 1; i < 6; i++) {
+				dev->bbu += buf[i];
+				if (i != 5)
+					dev->bbu <<= 8;
+			}
+			dev_dbg(&dev->interface->dev, "%s count: %lld\n",
+				__func__, dev->bbu);
+			spin_unlock_irqrestore(&dev->lock, flags);
+
+			kill_fasync(&dev->async_queue, SIGIO, POLL_IN);
+		}
+		else
+			dev_dbg(&dev->interface->dev,
+				"data format error - no EOF\n");
+		break;
+	case CMD_ACK:
+		dev_dbg(&dev->interface->dev, "%s ack: %c\n",
+			__func__, buf[1]);
+		wake_up_interruptible(&dev->waitq);
+		break;
+	}
+
+	retval = usb_submit_urb(dev->urb, GFP_ATOMIC);
+	if (retval) {
+		dev_err(&dev->interface->dev, "%s - usb_submit_urb failed: %d\n",
+			__func__, retval);
+	}
+}
+
+static int yurex_probe(struct usb_interface *interface, const struct usb_device_id *id)
+{
+	struct usb_yurex *dev;
+	struct usb_host_interface *iface_desc;
+	struct usb_endpoint_descriptor *endpoint;
+	int retval = -ENOMEM;
+	DEFINE_WAIT(wait);
+	int res;
+
+	/* allocate memory for our device state and initialize it */
+	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+	if (!dev)
+		goto error;
+	kref_init(&dev->kref);
+	mutex_init(&dev->io_mutex);
+	spin_lock_init(&dev->lock);
+	init_waitqueue_head(&dev->waitq);
+
+	dev->udev = usb_get_dev(interface_to_usbdev(interface));
+	dev->interface = usb_get_intf(interface);
+
+	/* set up the endpoint information */
+	iface_desc = interface->cur_altsetting;
+	res = usb_find_int_in_endpoint(iface_desc, &endpoint);
+	if (res) {
+		dev_err(&interface->dev, "Could not find endpoints\n");
+		retval = res;
+		goto error;
+	}
+
+	dev->int_in_endpointAddr = endpoint->bEndpointAddress;
+
+	/* allocate control URB */
+	dev->cntl_urb = usb_alloc_urb(0, GFP_KERNEL);
+	if (!dev->cntl_urb)
+		goto error;
+
+	/* allocate buffer for control req */
+	dev->cntl_req = kmalloc(YUREX_BUF_SIZE, GFP_KERNEL);
+	if (!dev->cntl_req)
+		goto error;
+
+	/* allocate buffer for control msg */
+	dev->cntl_buffer = usb_alloc_coherent(dev->udev, YUREX_BUF_SIZE,
+					      GFP_KERNEL,
+					      &dev->cntl_urb->transfer_dma);
+	if (!dev->cntl_buffer) {
+		dev_err(&interface->dev, "Could not allocate cntl_buffer\n");
+		goto error;
+	}
+
+	/* configure control URB */
+	dev->cntl_req->bRequestType = USB_DIR_OUT | USB_TYPE_CLASS |
+				      USB_RECIP_INTERFACE;
+	dev->cntl_req->bRequest	= HID_REQ_SET_REPORT;
+	dev->cntl_req->wValue	= cpu_to_le16((HID_OUTPUT_REPORT + 1) << 8);
+	dev->cntl_req->wIndex	= cpu_to_le16(iface_desc->desc.bInterfaceNumber);
+	dev->cntl_req->wLength	= cpu_to_le16(YUREX_BUF_SIZE);
+
+	usb_fill_control_urb(dev->cntl_urb, dev->udev,
+			     usb_sndctrlpipe(dev->udev, 0),
+			     (void *)dev->cntl_req, dev->cntl_buffer,
+			     YUREX_BUF_SIZE, yurex_control_callback, dev);
+	dev->cntl_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
+
+
+	/* allocate interrupt URB */
+	dev->urb = usb_alloc_urb(0, GFP_KERNEL);
+	if (!dev->urb)
+		goto error;
+
+	/* allocate buffer for interrupt in */
+	dev->int_buffer = usb_alloc_coherent(dev->udev, YUREX_BUF_SIZE,
+					GFP_KERNEL, &dev->urb->transfer_dma);
+	if (!dev->int_buffer) {
+		dev_err(&interface->dev, "Could not allocate int_buffer\n");
+		goto error;
+	}
+
+	/* configure interrupt URB */
+	usb_fill_int_urb(dev->urb, dev->udev,
+			 usb_rcvintpipe(dev->udev, dev->int_in_endpointAddr),
+			 dev->int_buffer, YUREX_BUF_SIZE, yurex_interrupt,
+			 dev, 1);
+	dev->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
+	if (usb_submit_urb(dev->urb, GFP_KERNEL)) {
+		retval = -EIO;
+		dev_err(&interface->dev, "Could not submitting URB\n");
+		goto error;
+	}
+
+	/* save our data pointer in this interface device */
+	usb_set_intfdata(interface, dev);
+	dev->bbu = -1;
+
+	/* we can register the device now, as it is ready */
+	retval = usb_register_dev(interface, &yurex_class);
+	if (retval) {
+		dev_err(&interface->dev,
+			"Not able to get a minor for this device.\n");
+		usb_set_intfdata(interface, NULL);
+		goto error;
+	}
+
+	dev_info(&interface->dev,
+		 "USB YUREX device now attached to Yurex #%d\n",
+		 interface->minor);
+
+	return 0;
+
+error:
+	if (dev)
+		/* this frees allocated memory */
+		kref_put(&dev->kref, yurex_delete);
+	return retval;
+}
+
+static void yurex_disconnect(struct usb_interface *interface)
+{
+	struct usb_yurex *dev;
+	int minor = interface->minor;
+
+	dev = usb_get_intfdata(interface);
+	usb_set_intfdata(interface, NULL);
+
+	/* give back our minor */
+	usb_deregister_dev(interface, &yurex_class);
+
+	/* prevent more I/O from starting */
+	usb_poison_urb(dev->urb);
+	usb_poison_urb(dev->cntl_urb);
+	mutex_lock(&dev->io_mutex);
+	dev->disconnected = 1;
+	mutex_unlock(&dev->io_mutex);
+
+	/* wakeup waiters */
+	kill_fasync(&dev->async_queue, SIGIO, POLL_IN);
+	wake_up_interruptible(&dev->waitq);
+
+	/* decrement our usage count */
+	kref_put(&dev->kref, yurex_delete);
+
+	dev_info(&interface->dev, "USB YUREX #%d now disconnected\n", minor);
+}
+
+static struct usb_driver yurex_driver = {
+	.name =		"yurex",
+	.probe =	yurex_probe,
+	.disconnect =	yurex_disconnect,
+	.id_table =	yurex_table,
+};
+
+
+static int yurex_fasync(int fd, struct file *file, int on)
+{
+	struct usb_yurex *dev;
+
+	dev = file->private_data;
+	return fasync_helper(fd, file, on, &dev->async_queue);
+}
+
+static int yurex_open(struct inode *inode, struct file *file)
+{
+	struct usb_yurex *dev;
+	struct usb_interface *interface;
+	int subminor;
+	int retval = 0;
+
+	subminor = iminor(inode);
+
+	interface = usb_find_interface(&yurex_driver, subminor);
+	if (!interface) {
+		printk(KERN_ERR "%s - error, can't find device for minor %d",
+		       __func__, subminor);
+		retval = -ENODEV;
+		goto exit;
+	}
+
+	dev = usb_get_intfdata(interface);
+	if (!dev) {
+		retval = -ENODEV;
+		goto exit;
+	}
+
+	/* increment our usage count for the device */
+	kref_get(&dev->kref);
+
+	/* save our object in the file's private structure */
+	mutex_lock(&dev->io_mutex);
+	file->private_data = dev;
+	mutex_unlock(&dev->io_mutex);
+
+exit:
+	return retval;
+}
+
+static int yurex_release(struct inode *inode, struct file *file)
+{
+	struct usb_yurex *dev;
+
+	dev = file->private_data;
+	if (dev == NULL)
+		return -ENODEV;
+
+	/* decrement the count on our device */
+	kref_put(&dev->kref, yurex_delete);
+	return 0;
+}
+
+static ssize_t yurex_read(struct file *file, char __user *buffer, size_t count,
+			  loff_t *ppos)
+{
+	struct usb_yurex *dev;
+	int len = 0;
+	char in_buffer[20];
+	unsigned long flags;
+
+	dev = file->private_data;
+
+	mutex_lock(&dev->io_mutex);
+	if (dev->disconnected) {		/* already disconnected */
+		mutex_unlock(&dev->io_mutex);
+		return -ENODEV;
+	}
+
+	spin_lock_irqsave(&dev->lock, flags);
+	len = snprintf(in_buffer, 20, "%lld\n", dev->bbu);
+	spin_unlock_irqrestore(&dev->lock, flags);
+	mutex_unlock(&dev->io_mutex);
+
+	if (WARN_ON_ONCE(len >= sizeof(in_buffer)))
+		return -EIO;
+
+	return simple_read_from_buffer(buffer, count, ppos, in_buffer, len);
+}
+
+static ssize_t yurex_write(struct file *file, const char __user *user_buffer,
+			   size_t count, loff_t *ppos)
+{
+	struct usb_yurex *dev;
+	int i, set = 0, retval = 0;
+	char buffer[16 + 1];
+	char *data = buffer;
+	unsigned long long c, c2 = 0;
+	signed long timeout = 0;
+	DEFINE_WAIT(wait);
+
+	count = min(sizeof(buffer) - 1, count);
+	dev = file->private_data;
+
+	/* verify that we actually have some data to write */
+	if (count == 0)
+		goto error;
+
+	mutex_lock(&dev->io_mutex);
+	if (dev->disconnected) {		/* already disconnected */
+		mutex_unlock(&dev->io_mutex);
+		retval = -ENODEV;
+		goto error;
+	}
+
+	if (copy_from_user(buffer, user_buffer, count)) {
+		mutex_unlock(&dev->io_mutex);
+		retval = -EFAULT;
+		goto error;
+	}
+	buffer[count] = 0;
+	memset(dev->cntl_buffer, CMD_PADDING, YUREX_BUF_SIZE);
+
+	switch (buffer[0]) {
+	case CMD_ANIMATE:
+	case CMD_LED:
+		dev->cntl_buffer[0] = buffer[0];
+		dev->cntl_buffer[1] = buffer[1];
+		dev->cntl_buffer[2] = CMD_EOF;
+		break;
+	case CMD_READ:
+	case CMD_VERSION:
+		dev->cntl_buffer[0] = buffer[0];
+		dev->cntl_buffer[1] = 0x00;
+		dev->cntl_buffer[2] = CMD_EOF;
+		break;
+	case CMD_SET:
+		data++;
+		fallthrough;
+	case '0' ... '9':
+		set = 1;
+		c = c2 = simple_strtoull(data, NULL, 0);
+		dev->cntl_buffer[0] = CMD_SET;
+		for (i = 1; i < 6; i++) {
+			dev->cntl_buffer[i] = (c>>32) & 0xff;
+			c <<= 8;
+		}
+		buffer[6] = CMD_EOF;
+		break;
+	default:
+		mutex_unlock(&dev->io_mutex);
+		return -EINVAL;
+	}
+
+	/* send the data as the control msg */
+	prepare_to_wait(&dev->waitq, &wait, TASK_INTERRUPTIBLE);
+	dev_dbg(&dev->interface->dev, "%s - submit %c\n", __func__,
+		dev->cntl_buffer[0]);
+	retval = usb_submit_urb(dev->cntl_urb, GFP_ATOMIC);
+	if (retval >= 0)
+		timeout = schedule_timeout(YUREX_WRITE_TIMEOUT);
+	finish_wait(&dev->waitq, &wait);
+
+	/* make sure URB is idle after timeout or (spurious) CMD_ACK */
+	usb_kill_urb(dev->cntl_urb);
+
+	mutex_unlock(&dev->io_mutex);
+
+	if (retval < 0) {
+		dev_err(&dev->interface->dev,
+			"%s - failed to send bulk msg, error %d\n",
+			__func__, retval);
+		goto error;
+	}
+	if (set && timeout)
+		dev->bbu = c2;
+	return timeout ? count : -EIO;
+
+error:
+	return retval;
+}
+
+static const struct file_operations yurex_fops = {
+	.owner =	THIS_MODULE,
+	.read =		yurex_read,
+	.write =	yurex_write,
+	.open =		yurex_open,
+	.release =	yurex_release,
+	.fasync	=	yurex_fasync,
+	.llseek =	default_llseek,
+};
+
+module_usb_driver(yurex_driver);
+
+MODULE_LICENSE("GPL");