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, 873 insertions, 0 deletions

diff --git a/drivers/mfd/dln2.c b/drivers/mfd/dln2.c
new file mode 100644
index 000000000..6cd0b0c75
--- /dev/null
+++ b/drivers/mfd/dln2.c
@@ -0,0 +1,873 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Driver for the Diolan DLN-2 USB adapter
+ *
+ * Copyright (c) 2014 Intel Corporation
+ *
+ * Derived from:
+ *  i2c-diolan-u2c.c
+ *  Copyright (c) 2010-2011 Ericsson AB
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/usb.h>
+#include <linux/i2c.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/dln2.h>
+#include <linux/rculist.h>
+
+struct dln2_header {
+	__le16 size;
+	__le16 id;
+	__le16 echo;
+	__le16 handle;
+};
+
+struct dln2_response {
+	struct dln2_header hdr;
+	__le16 result;
+};
+
+#define DLN2_GENERIC_MODULE_ID		0x00
+#define DLN2_GENERIC_CMD(cmd)		DLN2_CMD(cmd, DLN2_GENERIC_MODULE_ID)
+#define CMD_GET_DEVICE_VER		DLN2_GENERIC_CMD(0x30)
+#define CMD_GET_DEVICE_SN		DLN2_GENERIC_CMD(0x31)
+
+#define DLN2_HW_ID			0x200
+#define DLN2_USB_TIMEOUT		200	/* in ms */
+#define DLN2_MAX_RX_SLOTS		16
+#define DLN2_MAX_URBS			16
+#define DLN2_RX_BUF_SIZE		512
+
+enum dln2_handle {
+	DLN2_HANDLE_EVENT = 0,		/* don't change, hardware defined */
+	DLN2_HANDLE_CTRL,
+	DLN2_HANDLE_GPIO,
+	DLN2_HANDLE_I2C,
+	DLN2_HANDLE_SPI,
+	DLN2_HANDLE_ADC,
+	DLN2_HANDLES
+};
+
+/*
+ * Receive context used between the receive demultiplexer and the transfer
+ * routine. While sending a request the transfer routine will look for a free
+ * receive context and use it to wait for a response and to receive the URB and
+ * thus the response data.
+ */
+struct dln2_rx_context {
+	/* completion used to wait for a response */
+	struct completion done;
+
+	/* if non-NULL the URB contains the response */
+	struct urb *urb;
+
+	/* if true then this context is used to wait for a response */
+	bool in_use;
+};
+
+/*
+ * Receive contexts for a particular DLN2 module (i2c, gpio, etc.). We use the
+ * handle header field to identify the module in dln2_dev.mod_rx_slots and then
+ * the echo header field to index the slots field and find the receive context
+ * for a particular request.
+ */
+struct dln2_mod_rx_slots {
+	/* RX slots bitmap */
+	DECLARE_BITMAP(bmap, DLN2_MAX_RX_SLOTS);
+
+	/* used to wait for a free RX slot */
+	wait_queue_head_t wq;
+
+	/* used to wait for an RX operation to complete */
+	struct dln2_rx_context slots[DLN2_MAX_RX_SLOTS];
+
+	/* avoid races between alloc/free_rx_slot and dln2_rx_transfer */
+	spinlock_t lock;
+};
+
+struct dln2_dev {
+	struct usb_device *usb_dev;
+	struct usb_interface *interface;
+	u8 ep_in;
+	u8 ep_out;
+
+	struct urb *rx_urb[DLN2_MAX_URBS];
+	void *rx_buf[DLN2_MAX_URBS];
+
+	struct dln2_mod_rx_slots mod_rx_slots[DLN2_HANDLES];
+
+	struct list_head event_cb_list;
+	spinlock_t event_cb_lock;
+
+	bool disconnect;
+	int active_transfers;
+	wait_queue_head_t disconnect_wq;
+	spinlock_t disconnect_lock;
+};
+
+struct dln2_event_cb_entry {
+	struct list_head list;
+	u16 id;
+	struct platform_device *pdev;
+	dln2_event_cb_t callback;
+};
+
+int dln2_register_event_cb(struct platform_device *pdev, u16 id,
+			   dln2_event_cb_t event_cb)
+{
+	struct dln2_dev *dln2 = dev_get_drvdata(pdev->dev.parent);
+	struct dln2_event_cb_entry *i, *entry;
+	unsigned long flags;
+	int ret = 0;
+
+	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+	if (!entry)
+		return -ENOMEM;
+
+	entry->id = id;
+	entry->callback = event_cb;
+	entry->pdev = pdev;
+
+	spin_lock_irqsave(&dln2->event_cb_lock, flags);
+
+	list_for_each_entry(i, &dln2->event_cb_list, list) {
+		if (i->id == id) {
+			ret = -EBUSY;
+			break;
+		}
+	}
+
+	if (!ret)
+		list_add_rcu(&entry->list, &dln2->event_cb_list);
+
+	spin_unlock_irqrestore(&dln2->event_cb_lock, flags);
+
+	if (ret)
+		kfree(entry);
+
+	return ret;
+}
+EXPORT_SYMBOL(dln2_register_event_cb);
+
+void dln2_unregister_event_cb(struct platform_device *pdev, u16 id)
+{
+	struct dln2_dev *dln2 = dev_get_drvdata(pdev->dev.parent);
+	struct dln2_event_cb_entry *i;
+	unsigned long flags;
+	bool found = false;
+
+	spin_lock_irqsave(&dln2->event_cb_lock, flags);
+
+	list_for_each_entry(i, &dln2->event_cb_list, list) {
+		if (i->id == id) {
+			list_del_rcu(&i->list);
+			found = true;
+			break;
+		}
+	}
+
+	spin_unlock_irqrestore(&dln2->event_cb_lock, flags);
+
+	if (found) {
+		synchronize_rcu();
+		kfree(i);
+	}
+}
+EXPORT_SYMBOL(dln2_unregister_event_cb);
+
+/*
+ * Returns true if a valid transfer slot is found. In this case the URB must not
+ * be resubmitted immediately in dln2_rx as we need the data when dln2_transfer
+ * is woke up. It will be resubmitted there.
+ */
+static bool dln2_transfer_complete(struct dln2_dev *dln2, struct urb *urb,
+				   u16 handle, u16 rx_slot)
+{
+	struct device *dev = &dln2->interface->dev;
+	struct dln2_mod_rx_slots *rxs = &dln2->mod_rx_slots[handle];
+	struct dln2_rx_context *rxc;
+	unsigned long flags;
+	bool valid_slot = false;
+
+	if (rx_slot >= DLN2_MAX_RX_SLOTS)
+		goto out;
+
+	rxc = &rxs->slots[rx_slot];
+
+	spin_lock_irqsave(&rxs->lock, flags);
+	if (rxc->in_use && !rxc->urb) {
+		rxc->urb = urb;
+		complete(&rxc->done);
+		valid_slot = true;
+	}
+	spin_unlock_irqrestore(&rxs->lock, flags);
+
+out:
+	if (!valid_slot)
+		dev_warn(dev, "bad/late response %d/%d\n", handle, rx_slot);
+
+	return valid_slot;
+}
+
+static void dln2_run_event_callbacks(struct dln2_dev *dln2, u16 id, u16 echo,
+				     void *data, int len)
+{
+	struct dln2_event_cb_entry *i;
+
+	rcu_read_lock();
+
+	list_for_each_entry_rcu(i, &dln2->event_cb_list, list) {
+		if (i->id == id) {
+			i->callback(i->pdev, echo, data, len);
+			break;
+		}
+	}
+
+	rcu_read_unlock();
+}
+
+static void dln2_rx(struct urb *urb)
+{
+	struct dln2_dev *dln2 = urb->context;
+	struct dln2_header *hdr = urb->transfer_buffer;
+	struct device *dev = &dln2->interface->dev;
+	u16 id, echo, handle, size;
+	u8 *data;
+	int len;
+	int err;
+
+	switch (urb->status) {
+	case 0:
+		/* success */
+		break;
+	case -ECONNRESET:
+	case -ENOENT:
+	case -ESHUTDOWN:
+	case -EPIPE:
+		/* this urb is terminated, clean up */
+		dev_dbg(dev, "urb shutting down with status %d\n", urb->status);
+		return;
+	default:
+		dev_dbg(dev, "nonzero urb status received %d\n", urb->status);
+		goto out;
+	}
+
+	if (urb->actual_length < sizeof(struct dln2_header)) {
+		dev_err(dev, "short response: %d\n", urb->actual_length);
+		goto out;
+	}
+
+	handle = le16_to_cpu(hdr->handle);
+	id = le16_to_cpu(hdr->id);
+	echo = le16_to_cpu(hdr->echo);
+	size = le16_to_cpu(hdr->size);
+
+	if (size != urb->actual_length) {
+		dev_err(dev, "size mismatch: handle %x cmd %x echo %x size %d actual %d\n",
+			handle, id, echo, size, urb->actual_length);
+		goto out;
+	}
+
+	if (handle >= DLN2_HANDLES) {
+		dev_warn(dev, "invalid handle %d\n", handle);
+		goto out;
+	}
+
+	data = urb->transfer_buffer + sizeof(struct dln2_header);
+	len = urb->actual_length - sizeof(struct dln2_header);
+
+	if (handle == DLN2_HANDLE_EVENT) {
+		unsigned long flags;
+
+		spin_lock_irqsave(&dln2->event_cb_lock, flags);
+		dln2_run_event_callbacks(dln2, id, echo, data, len);
+		spin_unlock_irqrestore(&dln2->event_cb_lock, flags);
+	} else {
+		/* URB will be re-submitted in _dln2_transfer (free_rx_slot) */
+		if (dln2_transfer_complete(dln2, urb, handle, echo))
+			return;
+	}
+
+out:
+	err = usb_submit_urb(urb, GFP_ATOMIC);
+	if (err < 0)
+		dev_err(dev, "failed to resubmit RX URB: %d\n", err);
+}
+
+static void *dln2_prep_buf(u16 handle, u16 cmd, u16 echo, const void *obuf,
+			   int *obuf_len, gfp_t gfp)
+{
+	int len;
+	void *buf;
+	struct dln2_header *hdr;
+
+	len = *obuf_len + sizeof(*hdr);
+	buf = kmalloc(len, gfp);
+	if (!buf)
+		return NULL;
+
+	hdr = (struct dln2_header *)buf;
+	hdr->id = cpu_to_le16(cmd);
+	hdr->size = cpu_to_le16(len);
+	hdr->echo = cpu_to_le16(echo);
+	hdr->handle = cpu_to_le16(handle);
+
+	memcpy(buf + sizeof(*hdr), obuf, *obuf_len);
+
+	*obuf_len = len;
+
+	return buf;
+}
+
+static int dln2_send_wait(struct dln2_dev *dln2, u16 handle, u16 cmd, u16 echo,
+			  const void *obuf, int obuf_len)
+{
+	int ret = 0;
+	int len = obuf_len;
+	void *buf;
+	int actual;
+
+	buf = dln2_prep_buf(handle, cmd, echo, obuf, &len, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	ret = usb_bulk_msg(dln2->usb_dev,
+			   usb_sndbulkpipe(dln2->usb_dev, dln2->ep_out),
+			   buf, len, &actual, DLN2_USB_TIMEOUT);
+
+	kfree(buf);
+
+	return ret;
+}
+
+static bool find_free_slot(struct dln2_dev *dln2, u16 handle, int *slot)
+{
+	struct dln2_mod_rx_slots *rxs;
+	unsigned long flags;
+
+	if (dln2->disconnect) {
+		*slot = -ENODEV;
+		return true;
+	}
+
+	rxs = &dln2->mod_rx_slots[handle];
+
+	spin_lock_irqsave(&rxs->lock, flags);
+
+	*slot = find_first_zero_bit(rxs->bmap, DLN2_MAX_RX_SLOTS);
+
+	if (*slot < DLN2_MAX_RX_SLOTS) {
+		struct dln2_rx_context *rxc = &rxs->slots[*slot];
+
+		set_bit(*slot, rxs->bmap);
+		rxc->in_use = true;
+	}
+
+	spin_unlock_irqrestore(&rxs->lock, flags);
+
+	return *slot < DLN2_MAX_RX_SLOTS;
+}
+
+static int alloc_rx_slot(struct dln2_dev *dln2, u16 handle)
+{
+	int ret;
+	int slot;
+
+	/*
+	 * No need to timeout here, the wait is bounded by the timeout in
+	 * _dln2_transfer.
+	 */
+	ret = wait_event_interruptible(dln2->mod_rx_slots[handle].wq,
+				       find_free_slot(dln2, handle, &slot));
+	if (ret < 0)
+		return ret;
+
+	return slot;
+}
+
+static void free_rx_slot(struct dln2_dev *dln2, u16 handle, int slot)
+{
+	struct dln2_mod_rx_slots *rxs;
+	struct urb *urb = NULL;
+	unsigned long flags;
+	struct dln2_rx_context *rxc;
+
+	rxs = &dln2->mod_rx_slots[handle];
+
+	spin_lock_irqsave(&rxs->lock, flags);
+
+	clear_bit(slot, rxs->bmap);
+
+	rxc = &rxs->slots[slot];
+	rxc->in_use = false;
+	urb = rxc->urb;
+	rxc->urb = NULL;
+	reinit_completion(&rxc->done);
+
+	spin_unlock_irqrestore(&rxs->lock, flags);
+
+	if (urb) {
+		int err;
+		struct device *dev = &dln2->interface->dev;
+
+		err = usb_submit_urb(urb, GFP_KERNEL);
+		if (err < 0)
+			dev_err(dev, "failed to resubmit RX URB: %d\n", err);
+	}
+
+	wake_up_interruptible(&rxs->wq);
+}
+
+static int _dln2_transfer(struct dln2_dev *dln2, u16 handle, u16 cmd,
+			  const void *obuf, unsigned obuf_len,
+			  void *ibuf, unsigned *ibuf_len)
+{
+	int ret = 0;
+	int rx_slot;
+	struct dln2_response *rsp;
+	struct dln2_rx_context *rxc;
+	struct device *dev = &dln2->interface->dev;
+	const unsigned long timeout = msecs_to_jiffies(DLN2_USB_TIMEOUT);
+	struct dln2_mod_rx_slots *rxs = &dln2->mod_rx_slots[handle];
+	int size;
+
+	spin_lock(&dln2->disconnect_lock);
+	if (!dln2->disconnect)
+		dln2->active_transfers++;
+	else
+		ret = -ENODEV;
+	spin_unlock(&dln2->disconnect_lock);
+
+	if (ret)
+		return ret;
+
+	rx_slot = alloc_rx_slot(dln2, handle);
+	if (rx_slot < 0) {
+		ret = rx_slot;
+		goto out_decr;
+	}
+
+	ret = dln2_send_wait(dln2, handle, cmd, rx_slot, obuf, obuf_len);
+	if (ret < 0) {
+		dev_err(dev, "USB write failed: %d\n", ret);
+		goto out_free_rx_slot;
+	}
+
+	rxc = &rxs->slots[rx_slot];
+
+	ret = wait_for_completion_interruptible_timeout(&rxc->done, timeout);
+	if (ret <= 0) {
+		if (!ret)
+			ret = -ETIMEDOUT;
+		goto out_free_rx_slot;
+	} else {
+		ret = 0;
+	}
+
+	if (dln2->disconnect) {
+		ret = -ENODEV;
+		goto out_free_rx_slot;
+	}
+
+	/* if we got here we know that the response header has been checked */
+	rsp = rxc->urb->transfer_buffer;
+	size = le16_to_cpu(rsp->hdr.size);
+
+	if (size < sizeof(*rsp)) {
+		ret = -EPROTO;
+		goto out_free_rx_slot;
+	}
+
+	if (le16_to_cpu(rsp->result) > 0x80) {
+		dev_dbg(dev, "%d received response with error %d\n",
+			handle, le16_to_cpu(rsp->result));
+		ret = -EREMOTEIO;
+		goto out_free_rx_slot;
+	}
+
+	if (!ibuf)
+		goto out_free_rx_slot;
+
+	if (*ibuf_len > size - sizeof(*rsp))
+		*ibuf_len = size - sizeof(*rsp);
+
+	memcpy(ibuf, rsp + 1, *ibuf_len);
+
+out_free_rx_slot:
+	free_rx_slot(dln2, handle, rx_slot);
+out_decr:
+	spin_lock(&dln2->disconnect_lock);
+	dln2->active_transfers--;
+	spin_unlock(&dln2->disconnect_lock);
+	if (dln2->disconnect)
+		wake_up(&dln2->disconnect_wq);
+
+	return ret;
+}
+
+int dln2_transfer(struct platform_device *pdev, u16 cmd,
+		  const void *obuf, unsigned obuf_len,
+		  void *ibuf, unsigned *ibuf_len)
+{
+	struct dln2_platform_data *dln2_pdata;
+	struct dln2_dev *dln2;
+	u16 handle;
+
+	dln2 = dev_get_drvdata(pdev->dev.parent);
+	dln2_pdata = dev_get_platdata(&pdev->dev);
+	handle = dln2_pdata->handle;
+
+	return _dln2_transfer(dln2, handle, cmd, obuf, obuf_len, ibuf,
+			      ibuf_len);
+}
+EXPORT_SYMBOL(dln2_transfer);
+
+static int dln2_check_hw(struct dln2_dev *dln2)
+{
+	int ret;
+	__le32 hw_type;
+	int len = sizeof(hw_type);
+
+	ret = _dln2_transfer(dln2, DLN2_HANDLE_CTRL, CMD_GET_DEVICE_VER,
+			     NULL, 0, &hw_type, &len);
+	if (ret < 0)
+		return ret;
+	if (len < sizeof(hw_type))
+		return -EREMOTEIO;
+
+	if (le32_to_cpu(hw_type) != DLN2_HW_ID) {
+		dev_err(&dln2->interface->dev, "Device ID 0x%x not supported\n",
+			le32_to_cpu(hw_type));
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static int dln2_print_serialno(struct dln2_dev *dln2)
+{
+	int ret;
+	__le32 serial_no;
+	int len = sizeof(serial_no);
+	struct device *dev = &dln2->interface->dev;
+
+	ret = _dln2_transfer(dln2, DLN2_HANDLE_CTRL, CMD_GET_DEVICE_SN, NULL, 0,
+			     &serial_no, &len);
+	if (ret < 0)
+		return ret;
+	if (len < sizeof(serial_no))
+		return -EREMOTEIO;
+
+	dev_info(dev, "Diolan DLN2 serial %u\n", le32_to_cpu(serial_no));
+
+	return 0;
+}
+
+static int dln2_hw_init(struct dln2_dev *dln2)
+{
+	int ret;
+
+	ret = dln2_check_hw(dln2);
+	if (ret < 0)
+		return ret;
+
+	return dln2_print_serialno(dln2);
+}
+
+static void dln2_free_rx_urbs(struct dln2_dev *dln2)
+{
+	int i;
+
+	for (i = 0; i < DLN2_MAX_URBS; i++) {
+		usb_free_urb(dln2->rx_urb[i]);
+		kfree(dln2->rx_buf[i]);
+	}
+}
+
+static void dln2_stop_rx_urbs(struct dln2_dev *dln2)
+{
+	int i;
+
+	for (i = 0; i < DLN2_MAX_URBS; i++)
+		usb_kill_urb(dln2->rx_urb[i]);
+}
+
+static void dln2_free(struct dln2_dev *dln2)
+{
+	dln2_free_rx_urbs(dln2);
+	usb_put_dev(dln2->usb_dev);
+	kfree(dln2);
+}
+
+static int dln2_setup_rx_urbs(struct dln2_dev *dln2,
+			      struct usb_host_interface *hostif)
+{
+	int i;
+	const int rx_max_size = DLN2_RX_BUF_SIZE;
+
+	for (i = 0; i < DLN2_MAX_URBS; i++) {
+		dln2->rx_buf[i] = kmalloc(rx_max_size, GFP_KERNEL);
+		if (!dln2->rx_buf[i])
+			return -ENOMEM;
+
+		dln2->rx_urb[i] = usb_alloc_urb(0, GFP_KERNEL);
+		if (!dln2->rx_urb[i])
+			return -ENOMEM;
+
+		usb_fill_bulk_urb(dln2->rx_urb[i], dln2->usb_dev,
+				  usb_rcvbulkpipe(dln2->usb_dev, dln2->ep_in),
+				  dln2->rx_buf[i], rx_max_size, dln2_rx, dln2);
+	}
+
+	return 0;
+}
+
+static int dln2_start_rx_urbs(struct dln2_dev *dln2, gfp_t gfp)
+{
+	struct device *dev = &dln2->interface->dev;
+	int ret;
+	int i;
+
+	for (i = 0; i < DLN2_MAX_URBS; i++) {
+		ret = usb_submit_urb(dln2->rx_urb[i], gfp);
+		if (ret < 0) {
+			dev_err(dev, "failed to submit RX URB: %d\n", ret);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+enum {
+	DLN2_ACPI_MATCH_GPIO	= 0,
+	DLN2_ACPI_MATCH_I2C	= 1,
+	DLN2_ACPI_MATCH_SPI	= 2,
+	DLN2_ACPI_MATCH_ADC	= 3,
+};
+
+static struct dln2_platform_data dln2_pdata_gpio = {
+	.handle = DLN2_HANDLE_GPIO,
+};
+
+static struct mfd_cell_acpi_match dln2_acpi_match_gpio = {
+	.adr = DLN2_ACPI_MATCH_GPIO,
+};
+
+/* Only one I2C port seems to be supported on current hardware */
+static struct dln2_platform_data dln2_pdata_i2c = {
+	.handle = DLN2_HANDLE_I2C,
+	.port = 0,
+};
+
+static struct mfd_cell_acpi_match dln2_acpi_match_i2c = {
+	.adr = DLN2_ACPI_MATCH_I2C,
+};
+
+/* Only one SPI port supported */
+static struct dln2_platform_data dln2_pdata_spi = {
+	.handle = DLN2_HANDLE_SPI,
+	.port = 0,
+};
+
+static struct mfd_cell_acpi_match dln2_acpi_match_spi = {
+	.adr = DLN2_ACPI_MATCH_SPI,
+};
+
+/* Only one ADC port supported */
+static struct dln2_platform_data dln2_pdata_adc = {
+	.handle = DLN2_HANDLE_ADC,
+	.port = 0,
+};
+
+static struct mfd_cell_acpi_match dln2_acpi_match_adc = {
+	.adr = DLN2_ACPI_MATCH_ADC,
+};
+
+static const struct mfd_cell dln2_devs[] = {
+	{
+		.name = "dln2-gpio",
+		.acpi_match = &dln2_acpi_match_gpio,
+		.platform_data = &dln2_pdata_gpio,
+		.pdata_size = sizeof(struct dln2_platform_data),
+	},
+	{
+		.name = "dln2-i2c",
+		.acpi_match = &dln2_acpi_match_i2c,
+		.platform_data = &dln2_pdata_i2c,
+		.pdata_size = sizeof(struct dln2_platform_data),
+	},
+	{
+		.name = "dln2-spi",
+		.acpi_match = &dln2_acpi_match_spi,
+		.platform_data = &dln2_pdata_spi,
+		.pdata_size = sizeof(struct dln2_platform_data),
+	},
+	{
+		.name = "dln2-adc",
+		.acpi_match = &dln2_acpi_match_adc,
+		.platform_data = &dln2_pdata_adc,
+		.pdata_size = sizeof(struct dln2_platform_data),
+	},
+};
+
+static void dln2_stop(struct dln2_dev *dln2)
+{
+	int i, j;
+
+	/* don't allow starting new transfers */
+	spin_lock(&dln2->disconnect_lock);
+	dln2->disconnect = true;
+	spin_unlock(&dln2->disconnect_lock);
+
+	/* cancel in progress transfers */
+	for (i = 0; i < DLN2_HANDLES; i++) {
+		struct dln2_mod_rx_slots *rxs = &dln2->mod_rx_slots[i];
+		unsigned long flags;
+
+		spin_lock_irqsave(&rxs->lock, flags);
+
+		/* cancel all response waiters */
+		for (j = 0; j < DLN2_MAX_RX_SLOTS; j++) {
+			struct dln2_rx_context *rxc = &rxs->slots[j];
+
+			if (rxc->in_use)
+				complete(&rxc->done);
+		}
+
+		spin_unlock_irqrestore(&rxs->lock, flags);
+	}
+
+	/* wait for transfers to end */
+	wait_event(dln2->disconnect_wq, !dln2->active_transfers);
+
+	dln2_stop_rx_urbs(dln2);
+}
+
+static void dln2_disconnect(struct usb_interface *interface)
+{
+	struct dln2_dev *dln2 = usb_get_intfdata(interface);
+
+	dln2_stop(dln2);
+
+	mfd_remove_devices(&interface->dev);
+
+	dln2_free(dln2);
+}
+
+static int dln2_probe(struct usb_interface *interface,
+		      const struct usb_device_id *usb_id)
+{
+	struct usb_host_interface *hostif = interface->cur_altsetting;
+	struct usb_endpoint_descriptor *epin;
+	struct usb_endpoint_descriptor *epout;
+	struct device *dev = &interface->dev;
+	struct dln2_dev *dln2;
+	int ret;
+	int i, j;
+
+	if (hostif->desc.bInterfaceNumber != 0)
+		return -ENODEV;
+
+	ret = usb_find_common_endpoints(hostif, &epin, &epout, NULL, NULL);
+	if (ret)
+		return ret;
+
+	dln2 = kzalloc(sizeof(*dln2), GFP_KERNEL);
+	if (!dln2)
+		return -ENOMEM;
+
+	dln2->ep_out = epout->bEndpointAddress;
+	dln2->ep_in = epin->bEndpointAddress;
+	dln2->usb_dev = usb_get_dev(interface_to_usbdev(interface));
+	dln2->interface = interface;
+	usb_set_intfdata(interface, dln2);
+	init_waitqueue_head(&dln2->disconnect_wq);
+
+	for (i = 0; i < DLN2_HANDLES; i++) {
+		init_waitqueue_head(&dln2->mod_rx_slots[i].wq);
+		spin_lock_init(&dln2->mod_rx_slots[i].lock);
+		for (j = 0; j < DLN2_MAX_RX_SLOTS; j++)
+			init_completion(&dln2->mod_rx_slots[i].slots[j].done);
+	}
+
+	spin_lock_init(&dln2->event_cb_lock);
+	spin_lock_init(&dln2->disconnect_lock);
+	INIT_LIST_HEAD(&dln2->event_cb_list);
+
+	ret = dln2_setup_rx_urbs(dln2, hostif);
+	if (ret)
+		goto out_free;
+
+	ret = dln2_start_rx_urbs(dln2, GFP_KERNEL);
+	if (ret)
+		goto out_stop_rx;
+
+	ret = dln2_hw_init(dln2);
+	if (ret < 0) {
+		dev_err(dev, "failed to initialize hardware\n");
+		goto out_stop_rx;
+	}
+
+	ret = mfd_add_hotplug_devices(dev, dln2_devs, ARRAY_SIZE(dln2_devs));
+	if (ret != 0) {
+		dev_err(dev, "failed to add mfd devices to core\n");
+		goto out_stop_rx;
+	}
+
+	return 0;
+
+out_stop_rx:
+	dln2_stop_rx_urbs(dln2);
+
+out_free:
+	dln2_free(dln2);
+
+	return ret;
+}
+
+static int dln2_suspend(struct usb_interface *iface, pm_message_t message)
+{
+	struct dln2_dev *dln2 = usb_get_intfdata(iface);
+
+	dln2_stop(dln2);
+
+	return 0;
+}
+
+static int dln2_resume(struct usb_interface *iface)
+{
+	struct dln2_dev *dln2 = usb_get_intfdata(iface);
+
+	dln2->disconnect = false;
+
+	return dln2_start_rx_urbs(dln2, GFP_NOIO);
+}
+
+static const struct usb_device_id dln2_table[] = {
+	{ USB_DEVICE(0xa257, 0x2013) },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(usb, dln2_table);
+
+static struct usb_driver dln2_driver = {
+	.name = "dln2",
+	.probe = dln2_probe,
+	.disconnect = dln2_disconnect,
+	.id_table = dln2_table,
+	.suspend = dln2_suspend,
+	.resume = dln2_resume,
+};
+
+module_usb_driver(dln2_driver);
+
+MODULE_AUTHOR("Octavian Purdila <octavian.purdila@intel.com>");
+MODULE_DESCRIPTION("Core driver for the Diolan DLN2 interface adapter");
+MODULE_LICENSE("GPL v2");