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, 645 insertions, 0 deletions

diff --git a/drivers/i2c/busses/i2c-uniphier-f.c b/drivers/i2c/busses/i2c-uniphier-f.c
new file mode 100644
index 000000000..d7b622891
--- /dev/null
+++ b/drivers/i2c/busses/i2c-uniphier-f.c
@@ -0,0 +1,645 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2015 Masahiro Yamada <yamada.masahiro@socionext.com>
+ */
+
+#include <linux/clk.h>
+#include <linux/i2c.h>
+#include <linux/iopoll.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#define UNIPHIER_FI2C_CR	0x00	/* control register */
+#define     UNIPHIER_FI2C_CR_MST	BIT(3)	/* master mode */
+#define     UNIPHIER_FI2C_CR_STA	BIT(2)	/* start condition */
+#define     UNIPHIER_FI2C_CR_STO	BIT(1)	/* stop condition */
+#define     UNIPHIER_FI2C_CR_NACK	BIT(0)	/* do not return ACK */
+#define UNIPHIER_FI2C_DTTX	0x04	/* TX FIFO */
+#define     UNIPHIER_FI2C_DTTX_CMD	BIT(8)	/* send command (slave addr) */
+#define     UNIPHIER_FI2C_DTTX_RD	BIT(0)	/* read transaction */
+#define UNIPHIER_FI2C_DTRX	0x04	/* RX FIFO */
+#define UNIPHIER_FI2C_SLAD	0x0c	/* slave address */
+#define UNIPHIER_FI2C_CYC	0x10	/* clock cycle control */
+#define UNIPHIER_FI2C_LCTL	0x14	/* clock low period control */
+#define UNIPHIER_FI2C_SSUT	0x18	/* restart/stop setup time control */
+#define UNIPHIER_FI2C_DSUT	0x1c	/* data setup time control */
+#define UNIPHIER_FI2C_INT	0x20	/* interrupt status */
+#define UNIPHIER_FI2C_IE	0x24	/* interrupt enable */
+#define UNIPHIER_FI2C_IC	0x28	/* interrupt clear */
+#define     UNIPHIER_FI2C_INT_TE	BIT(9)	/* TX FIFO empty */
+#define     UNIPHIER_FI2C_INT_RF	BIT(8)	/* RX FIFO full */
+#define     UNIPHIER_FI2C_INT_TC	BIT(7)	/* send complete (STOP) */
+#define     UNIPHIER_FI2C_INT_RC	BIT(6)	/* receive complete (STOP) */
+#define     UNIPHIER_FI2C_INT_TB	BIT(5)	/* sent specified bytes */
+#define     UNIPHIER_FI2C_INT_RB	BIT(4)	/* received specified bytes */
+#define     UNIPHIER_FI2C_INT_NA	BIT(2)	/* no ACK */
+#define     UNIPHIER_FI2C_INT_AL	BIT(1)	/* arbitration lost */
+#define UNIPHIER_FI2C_SR	0x2c	/* status register */
+#define     UNIPHIER_FI2C_SR_DB		BIT(12)	/* device busy */
+#define     UNIPHIER_FI2C_SR_STS	BIT(11)	/* stop condition detected */
+#define     UNIPHIER_FI2C_SR_BB		BIT(8)	/* bus busy */
+#define     UNIPHIER_FI2C_SR_RFF	BIT(3)	/* RX FIFO full */
+#define     UNIPHIER_FI2C_SR_RNE	BIT(2)	/* RX FIFO not empty */
+#define     UNIPHIER_FI2C_SR_TNF	BIT(1)	/* TX FIFO not full */
+#define     UNIPHIER_FI2C_SR_TFE	BIT(0)	/* TX FIFO empty */
+#define UNIPHIER_FI2C_RST	0x34	/* reset control */
+#define     UNIPHIER_FI2C_RST_TBRST	BIT(2)	/* clear TX FIFO */
+#define     UNIPHIER_FI2C_RST_RBRST	BIT(1)	/* clear RX FIFO */
+#define     UNIPHIER_FI2C_RST_RST	BIT(0)	/* forcible bus reset */
+#define UNIPHIER_FI2C_BM	0x38	/* bus monitor */
+#define     UNIPHIER_FI2C_BM_SDAO	BIT(3)	/* output for SDA line */
+#define     UNIPHIER_FI2C_BM_SDAS	BIT(2)	/* readback of SDA line */
+#define     UNIPHIER_FI2C_BM_SCLO	BIT(1)	/* output for SCL line */
+#define     UNIPHIER_FI2C_BM_SCLS	BIT(0)	/* readback of SCL line */
+#define UNIPHIER_FI2C_NOISE	0x3c	/* noise filter control */
+#define UNIPHIER_FI2C_TBC	0x40	/* TX byte count setting */
+#define UNIPHIER_FI2C_RBC	0x44	/* RX byte count setting */
+#define UNIPHIER_FI2C_TBCM	0x48	/* TX byte count monitor */
+#define UNIPHIER_FI2C_RBCM	0x4c	/* RX byte count monitor */
+#define UNIPHIER_FI2C_BRST	0x50	/* bus reset */
+#define     UNIPHIER_FI2C_BRST_FOEN	BIT(1)	/* normal operation */
+#define     UNIPHIER_FI2C_BRST_RSCL	BIT(0)	/* release SCL */
+
+#define UNIPHIER_FI2C_INT_FAULTS	\
+				(UNIPHIER_FI2C_INT_NA | UNIPHIER_FI2C_INT_AL)
+#define UNIPHIER_FI2C_INT_STOP		\
+				(UNIPHIER_FI2C_INT_TC | UNIPHIER_FI2C_INT_RC)
+
+#define UNIPHIER_FI2C_RD		BIT(0)
+#define UNIPHIER_FI2C_STOP		BIT(1)
+#define UNIPHIER_FI2C_MANUAL_NACK	BIT(2)
+#define UNIPHIER_FI2C_BYTE_WISE		BIT(3)
+#define UNIPHIER_FI2C_DEFER_STOP_COMP	BIT(4)
+
+#define UNIPHIER_FI2C_FIFO_SIZE		8
+
+struct uniphier_fi2c_priv {
+	struct completion comp;
+	struct i2c_adapter adap;
+	void __iomem *membase;
+	struct clk *clk;
+	unsigned int len;
+	u8 *buf;
+	u32 enabled_irqs;
+	int error;
+	unsigned int flags;
+	unsigned int busy_cnt;
+	unsigned int clk_cycle;
+	spinlock_t lock;	/* IRQ synchronization */
+};
+
+static void uniphier_fi2c_fill_txfifo(struct uniphier_fi2c_priv *priv,
+				      bool first)
+{
+	int fifo_space = UNIPHIER_FI2C_FIFO_SIZE;
+
+	/*
+	 * TX-FIFO stores slave address in it for the first access.
+	 * Decrement the counter.
+	 */
+	if (first)
+		fifo_space--;
+
+	while (priv->len) {
+		if (fifo_space-- <= 0)
+			break;
+
+		writel(*priv->buf++, priv->membase + UNIPHIER_FI2C_DTTX);
+		priv->len--;
+	}
+}
+
+static void uniphier_fi2c_drain_rxfifo(struct uniphier_fi2c_priv *priv)
+{
+	int fifo_left = priv->flags & UNIPHIER_FI2C_BYTE_WISE ?
+						1 : UNIPHIER_FI2C_FIFO_SIZE;
+
+	while (priv->len) {
+		if (fifo_left-- <= 0)
+			break;
+
+		*priv->buf++ = readl(priv->membase + UNIPHIER_FI2C_DTRX);
+		priv->len--;
+	}
+}
+
+static void uniphier_fi2c_set_irqs(struct uniphier_fi2c_priv *priv)
+{
+	writel(priv->enabled_irqs, priv->membase + UNIPHIER_FI2C_IE);
+}
+
+static void uniphier_fi2c_clear_irqs(struct uniphier_fi2c_priv *priv,
+				     u32 mask)
+{
+	writel(mask, priv->membase + UNIPHIER_FI2C_IC);
+}
+
+static void uniphier_fi2c_stop(struct uniphier_fi2c_priv *priv)
+{
+	priv->enabled_irqs |= UNIPHIER_FI2C_INT_STOP;
+	uniphier_fi2c_set_irqs(priv);
+	writel(UNIPHIER_FI2C_CR_MST | UNIPHIER_FI2C_CR_STO,
+	       priv->membase + UNIPHIER_FI2C_CR);
+}
+
+static irqreturn_t uniphier_fi2c_interrupt(int irq, void *dev_id)
+{
+	struct uniphier_fi2c_priv *priv = dev_id;
+	u32 irq_status;
+
+	spin_lock(&priv->lock);
+
+	irq_status = readl(priv->membase + UNIPHIER_FI2C_INT);
+	irq_status &= priv->enabled_irqs;
+
+	if (irq_status & UNIPHIER_FI2C_INT_STOP)
+		goto complete;
+
+	if (unlikely(irq_status & UNIPHIER_FI2C_INT_AL)) {
+		priv->error = -EAGAIN;
+		goto complete;
+	}
+
+	if (unlikely(irq_status & UNIPHIER_FI2C_INT_NA)) {
+		priv->error = -ENXIO;
+		if (priv->flags & UNIPHIER_FI2C_RD) {
+			/*
+			 * work around a hardware bug:
+			 * The receive-completed interrupt is never set even if
+			 * STOP condition is detected after the address phase
+			 * of read transaction fails to get ACK.
+			 * To avoid time-out error, we issue STOP here,
+			 * but do not wait for its completion.
+			 * It should be checked after exiting this handler.
+			 */
+			uniphier_fi2c_stop(priv);
+			priv->flags |= UNIPHIER_FI2C_DEFER_STOP_COMP;
+			goto complete;
+		}
+		goto stop;
+	}
+
+	if (irq_status & UNIPHIER_FI2C_INT_TE) {
+		if (!priv->len)
+			goto data_done;
+
+		uniphier_fi2c_fill_txfifo(priv, false);
+		goto handled;
+	}
+
+	if (irq_status & (UNIPHIER_FI2C_INT_RF | UNIPHIER_FI2C_INT_RB)) {
+		uniphier_fi2c_drain_rxfifo(priv);
+		/*
+		 * If the number of bytes to read is multiple of the FIFO size
+		 * (msg->len == 8, 16, 24, ...), the INT_RF bit is set a little
+		 * earlier than INT_RB. We wait for INT_RB to confirm the
+		 * completion of the current message.
+		 */
+		if (!priv->len && (irq_status & UNIPHIER_FI2C_INT_RB))
+			goto data_done;
+
+		if (unlikely(priv->flags & UNIPHIER_FI2C_MANUAL_NACK)) {
+			if (priv->len <= UNIPHIER_FI2C_FIFO_SIZE &&
+			    !(priv->flags & UNIPHIER_FI2C_BYTE_WISE)) {
+				priv->enabled_irqs |= UNIPHIER_FI2C_INT_RB;
+				uniphier_fi2c_set_irqs(priv);
+				priv->flags |= UNIPHIER_FI2C_BYTE_WISE;
+			}
+			if (priv->len <= 1)
+				writel(UNIPHIER_FI2C_CR_MST |
+				       UNIPHIER_FI2C_CR_NACK,
+				       priv->membase + UNIPHIER_FI2C_CR);
+		}
+
+		goto handled;
+	}
+
+	spin_unlock(&priv->lock);
+
+	return IRQ_NONE;
+
+data_done:
+	if (priv->flags & UNIPHIER_FI2C_STOP) {
+stop:
+		uniphier_fi2c_stop(priv);
+	} else {
+complete:
+		priv->enabled_irqs = 0;
+		uniphier_fi2c_set_irqs(priv);
+		complete(&priv->comp);
+	}
+
+handled:
+	/*
+	 * This controller makes a pause while any bit of the IRQ status is
+	 * asserted. Clear the asserted bit to kick the controller just before
+	 * exiting the handler.
+	 */
+	uniphier_fi2c_clear_irqs(priv, irq_status);
+
+	spin_unlock(&priv->lock);
+
+	return IRQ_HANDLED;
+}
+
+static void uniphier_fi2c_tx_init(struct uniphier_fi2c_priv *priv, u16 addr,
+				  bool repeat)
+{
+	priv->enabled_irqs |= UNIPHIER_FI2C_INT_TE;
+	uniphier_fi2c_set_irqs(priv);
+
+	/* do not use TX byte counter */
+	writel(0, priv->membase + UNIPHIER_FI2C_TBC);
+	/* set slave address */
+	writel(UNIPHIER_FI2C_DTTX_CMD | addr << 1,
+	       priv->membase + UNIPHIER_FI2C_DTTX);
+	/*
+	 * First chunk of data. For a repeated START condition, do not write
+	 * data to the TX fifo here to avoid the timing issue.
+	 */
+	if (!repeat)
+		uniphier_fi2c_fill_txfifo(priv, true);
+}
+
+static void uniphier_fi2c_rx_init(struct uniphier_fi2c_priv *priv, u16 addr)
+{
+	priv->flags |= UNIPHIER_FI2C_RD;
+
+	if (likely(priv->len < 256)) {
+		/*
+		 * If possible, use RX byte counter.
+		 * It can automatically handle NACK for the last byte.
+		 */
+		writel(priv->len, priv->membase + UNIPHIER_FI2C_RBC);
+		priv->enabled_irqs |= UNIPHIER_FI2C_INT_RF |
+				      UNIPHIER_FI2C_INT_RB;
+	} else {
+		/*
+		 * The byte counter can not count over 256.  In this case,
+		 * do not use it at all.  Drain data when FIFO gets full,
+		 * but treat the last portion as a special case.
+		 */
+		writel(0, priv->membase + UNIPHIER_FI2C_RBC);
+		priv->flags |= UNIPHIER_FI2C_MANUAL_NACK;
+		priv->enabled_irqs |= UNIPHIER_FI2C_INT_RF;
+	}
+
+	uniphier_fi2c_set_irqs(priv);
+
+	/* set slave address with RD bit */
+	writel(UNIPHIER_FI2C_DTTX_CMD | UNIPHIER_FI2C_DTTX_RD | addr << 1,
+	       priv->membase + UNIPHIER_FI2C_DTTX);
+}
+
+static void uniphier_fi2c_reset(struct uniphier_fi2c_priv *priv)
+{
+	writel(UNIPHIER_FI2C_RST_RST, priv->membase + UNIPHIER_FI2C_RST);
+}
+
+static void uniphier_fi2c_prepare_operation(struct uniphier_fi2c_priv *priv)
+{
+	writel(UNIPHIER_FI2C_BRST_FOEN | UNIPHIER_FI2C_BRST_RSCL,
+	       priv->membase + UNIPHIER_FI2C_BRST);
+}
+
+static void uniphier_fi2c_recover(struct uniphier_fi2c_priv *priv)
+{
+	uniphier_fi2c_reset(priv);
+	i2c_recover_bus(&priv->adap);
+}
+
+static int uniphier_fi2c_master_xfer_one(struct i2c_adapter *adap,
+					 struct i2c_msg *msg, bool repeat,
+					 bool stop)
+{
+	struct uniphier_fi2c_priv *priv = i2c_get_adapdata(adap);
+	bool is_read = msg->flags & I2C_M_RD;
+	unsigned long time_left, flags;
+
+	priv->len = msg->len;
+	priv->buf = msg->buf;
+	priv->enabled_irqs = UNIPHIER_FI2C_INT_FAULTS;
+	priv->error = 0;
+	priv->flags = 0;
+
+	if (stop)
+		priv->flags |= UNIPHIER_FI2C_STOP;
+
+	reinit_completion(&priv->comp);
+	uniphier_fi2c_clear_irqs(priv, U32_MAX);
+	writel(UNIPHIER_FI2C_RST_TBRST | UNIPHIER_FI2C_RST_RBRST,
+	       priv->membase + UNIPHIER_FI2C_RST);	/* reset TX/RX FIFO */
+
+	spin_lock_irqsave(&priv->lock, flags);
+
+	if (is_read)
+		uniphier_fi2c_rx_init(priv, msg->addr);
+	else
+		uniphier_fi2c_tx_init(priv, msg->addr, repeat);
+
+	/*
+	 * For a repeated START condition, writing a slave address to the FIFO
+	 * kicks the controller. So, the UNIPHIER_FI2C_CR register should be
+	 * written only for a non-repeated START condition.
+	 */
+	if (!repeat)
+		writel(UNIPHIER_FI2C_CR_MST | UNIPHIER_FI2C_CR_STA,
+		       priv->membase + UNIPHIER_FI2C_CR);
+
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	time_left = wait_for_completion_timeout(&priv->comp, adap->timeout);
+
+	spin_lock_irqsave(&priv->lock, flags);
+	priv->enabled_irqs = 0;
+	uniphier_fi2c_set_irqs(priv);
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	if (!time_left) {
+		dev_err(&adap->dev, "transaction timeout.\n");
+		uniphier_fi2c_recover(priv);
+		return -ETIMEDOUT;
+	}
+
+	if (unlikely(priv->flags & UNIPHIER_FI2C_DEFER_STOP_COMP)) {
+		u32 status;
+		int ret;
+
+		ret = readl_poll_timeout(priv->membase + UNIPHIER_FI2C_SR,
+					 status,
+					 (status & UNIPHIER_FI2C_SR_STS) &&
+					 !(status & UNIPHIER_FI2C_SR_BB),
+					 1, 20);
+		if (ret) {
+			dev_err(&adap->dev,
+				"stop condition was not completed.\n");
+			uniphier_fi2c_recover(priv);
+			return ret;
+		}
+	}
+
+	return priv->error;
+}
+
+static int uniphier_fi2c_check_bus_busy(struct i2c_adapter *adap)
+{
+	struct uniphier_fi2c_priv *priv = i2c_get_adapdata(adap);
+
+	if (readl(priv->membase + UNIPHIER_FI2C_SR) & UNIPHIER_FI2C_SR_DB) {
+		if (priv->busy_cnt++ > 3) {
+			/*
+			 * If bus busy continues too long, it is probably
+			 * in a wrong state.  Try bus recovery.
+			 */
+			uniphier_fi2c_recover(priv);
+			priv->busy_cnt = 0;
+		}
+
+		return -EAGAIN;
+	}
+
+	priv->busy_cnt = 0;
+	return 0;
+}
+
+static int uniphier_fi2c_master_xfer(struct i2c_adapter *adap,
+				     struct i2c_msg *msgs, int num)
+{
+	struct i2c_msg *msg, *emsg = msgs + num;
+	bool repeat = false;
+	int ret;
+
+	ret = uniphier_fi2c_check_bus_busy(adap);
+	if (ret)
+		return ret;
+
+	for (msg = msgs; msg < emsg; msg++) {
+		/* Emit STOP if it is the last message or I2C_M_STOP is set. */
+		bool stop = (msg + 1 == emsg) || (msg->flags & I2C_M_STOP);
+
+		ret = uniphier_fi2c_master_xfer_one(adap, msg, repeat, stop);
+		if (ret)
+			return ret;
+
+		repeat = !stop;
+	}
+
+	return num;
+}
+
+static u32 uniphier_fi2c_functionality(struct i2c_adapter *adap)
+{
+	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static const struct i2c_algorithm uniphier_fi2c_algo = {
+	.master_xfer = uniphier_fi2c_master_xfer,
+	.functionality = uniphier_fi2c_functionality,
+};
+
+static int uniphier_fi2c_get_scl(struct i2c_adapter *adap)
+{
+	struct uniphier_fi2c_priv *priv = i2c_get_adapdata(adap);
+
+	return !!(readl(priv->membase + UNIPHIER_FI2C_BM) &
+							UNIPHIER_FI2C_BM_SCLS);
+}
+
+static void uniphier_fi2c_set_scl(struct i2c_adapter *adap, int val)
+{
+	struct uniphier_fi2c_priv *priv = i2c_get_adapdata(adap);
+
+	writel(val ? UNIPHIER_FI2C_BRST_RSCL : 0,
+	       priv->membase + UNIPHIER_FI2C_BRST);
+}
+
+static int uniphier_fi2c_get_sda(struct i2c_adapter *adap)
+{
+	struct uniphier_fi2c_priv *priv = i2c_get_adapdata(adap);
+
+	return !!(readl(priv->membase + UNIPHIER_FI2C_BM) &
+							UNIPHIER_FI2C_BM_SDAS);
+}
+
+static void uniphier_fi2c_unprepare_recovery(struct i2c_adapter *adap)
+{
+	uniphier_fi2c_prepare_operation(i2c_get_adapdata(adap));
+}
+
+static struct i2c_bus_recovery_info uniphier_fi2c_bus_recovery_info = {
+	.recover_bus = i2c_generic_scl_recovery,
+	.get_scl = uniphier_fi2c_get_scl,
+	.set_scl = uniphier_fi2c_set_scl,
+	.get_sda = uniphier_fi2c_get_sda,
+	.unprepare_recovery = uniphier_fi2c_unprepare_recovery,
+};
+
+static void uniphier_fi2c_hw_init(struct uniphier_fi2c_priv *priv)
+{
+	unsigned int cyc = priv->clk_cycle;
+	u32 tmp;
+
+	tmp = readl(priv->membase + UNIPHIER_FI2C_CR);
+	tmp |= UNIPHIER_FI2C_CR_MST;
+	writel(tmp, priv->membase + UNIPHIER_FI2C_CR);
+
+	uniphier_fi2c_reset(priv);
+
+	/*
+	 *  Standard-mode: tLOW + tHIGH = 10 us
+	 *  Fast-mode:     tLOW + tHIGH = 2.5 us
+	 */
+	writel(cyc, priv->membase + UNIPHIER_FI2C_CYC);
+	/*
+	 *  Standard-mode: tLOW = 4.7 us, tHIGH = 4.0 us, tBUF = 4.7 us
+	 *  Fast-mode:     tLOW = 1.3 us, tHIGH = 0.6 us, tBUF = 1.3 us
+	 * "tLow/tHIGH = 5/4" meets both.
+	 */
+	writel(cyc * 5 / 9, priv->membase + UNIPHIER_FI2C_LCTL);
+	/*
+	 *  Standard-mode: tHD;STA = 4.0 us, tSU;STA = 4.7 us, tSU;STO = 4.0 us
+	 *  Fast-mode:     tHD;STA = 0.6 us, tSU;STA = 0.6 us, tSU;STO = 0.6 us
+	 */
+	writel(cyc / 2, priv->membase + UNIPHIER_FI2C_SSUT);
+	/*
+	 *  Standard-mode: tSU;DAT = 250 ns
+	 *  Fast-mode:     tSU;DAT = 100 ns
+	 */
+	writel(cyc / 16, priv->membase + UNIPHIER_FI2C_DSUT);
+
+	uniphier_fi2c_prepare_operation(priv);
+}
+
+static int uniphier_fi2c_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct uniphier_fi2c_priv *priv;
+	u32 bus_speed;
+	unsigned long clk_rate;
+	int irq, ret;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->membase = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(priv->membase))
+		return PTR_ERR(priv->membase);
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
+
+	if (of_property_read_u32(dev->of_node, "clock-frequency", &bus_speed))
+		bus_speed = I2C_MAX_STANDARD_MODE_FREQ;
+
+	if (!bus_speed || bus_speed > I2C_MAX_FAST_MODE_FREQ) {
+		dev_err(dev, "invalid clock-frequency %d\n", bus_speed);
+		return -EINVAL;
+	}
+
+	priv->clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(priv->clk)) {
+		dev_err(dev, "failed to get clock\n");
+		return PTR_ERR(priv->clk);
+	}
+
+	ret = clk_prepare_enable(priv->clk);
+	if (ret)
+		return ret;
+
+	clk_rate = clk_get_rate(priv->clk);
+	if (!clk_rate) {
+		dev_err(dev, "input clock rate should not be zero\n");
+		ret = -EINVAL;
+		goto disable_clk;
+	}
+
+	priv->clk_cycle = clk_rate / bus_speed;
+	init_completion(&priv->comp);
+	spin_lock_init(&priv->lock);
+	priv->adap.owner = THIS_MODULE;
+	priv->adap.algo = &uniphier_fi2c_algo;
+	priv->adap.dev.parent = dev;
+	priv->adap.dev.of_node = dev->of_node;
+	strscpy(priv->adap.name, "UniPhier FI2C", sizeof(priv->adap.name));
+	priv->adap.bus_recovery_info = &uniphier_fi2c_bus_recovery_info;
+	i2c_set_adapdata(&priv->adap, priv);
+	platform_set_drvdata(pdev, priv);
+
+	uniphier_fi2c_hw_init(priv);
+
+	ret = devm_request_irq(dev, irq, uniphier_fi2c_interrupt, 0,
+			       pdev->name, priv);
+	if (ret) {
+		dev_err(dev, "failed to request irq %d\n", irq);
+		goto disable_clk;
+	}
+
+	ret = i2c_add_adapter(&priv->adap);
+disable_clk:
+	if (ret)
+		clk_disable_unprepare(priv->clk);
+
+	return ret;
+}
+
+static int uniphier_fi2c_remove(struct platform_device *pdev)
+{
+	struct uniphier_fi2c_priv *priv = platform_get_drvdata(pdev);
+
+	i2c_del_adapter(&priv->adap);
+	clk_disable_unprepare(priv->clk);
+
+	return 0;
+}
+
+static int __maybe_unused uniphier_fi2c_suspend(struct device *dev)
+{
+	struct uniphier_fi2c_priv *priv = dev_get_drvdata(dev);
+
+	clk_disable_unprepare(priv->clk);
+
+	return 0;
+}
+
+static int __maybe_unused uniphier_fi2c_resume(struct device *dev)
+{
+	struct uniphier_fi2c_priv *priv = dev_get_drvdata(dev);
+	int ret;
+
+	ret = clk_prepare_enable(priv->clk);
+	if (ret)
+		return ret;
+
+	uniphier_fi2c_hw_init(priv);
+
+	return 0;
+}
+
+static const struct dev_pm_ops uniphier_fi2c_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(uniphier_fi2c_suspend, uniphier_fi2c_resume)
+};
+
+static const struct of_device_id uniphier_fi2c_match[] = {
+	{ .compatible = "socionext,uniphier-fi2c" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, uniphier_fi2c_match);
+
+static struct platform_driver uniphier_fi2c_drv = {
+	.probe  = uniphier_fi2c_probe,
+	.remove = uniphier_fi2c_remove,
+	.driver = {
+		.name  = "uniphier-fi2c",
+		.of_match_table = uniphier_fi2c_match,
+		.pm = &uniphier_fi2c_pm_ops,
+	},
+};
+module_platform_driver(uniphier_fi2c_drv);
+
+MODULE_AUTHOR("Masahiro Yamada <yamada.masahiro@socionext.com>");
+MODULE_DESCRIPTION("UniPhier FIFO-builtin I2C bus driver");
+MODULE_LICENSE("GPL");