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().
  ...

3 files changed, 816 insertions, 0 deletions

diff --git a/drivers/staging/iio/impedance-analyzer/Kconfig b/drivers/staging/iio/impedance-analyzer/Kconfig
new file mode 100644
index 000000000..841648847
--- /dev/null
+++ b/drivers/staging/iio/impedance-analyzer/Kconfig
@@ -0,0 +1,19 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Impedance Converter, Network Analyzer drivers
+#
+menu "Network Analyzer, Impedance Converters"
+
+config AD5933
+	tristate "Analog Devices AD5933, AD5934 driver"
+	depends on I2C
+	select IIO_BUFFER
+	select IIO_KFIFO_BUF
+	help
+	  Say yes here to build support for Analog Devices Impedance Converter,
+	  Network Analyzer, AD5933/4.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called ad5933.
+
+endmenu
diff --git a/drivers/staging/iio/impedance-analyzer/Makefile b/drivers/staging/iio/impedance-analyzer/Makefile
new file mode 100644
index 000000000..b4e657a1a
--- /dev/null
+++ b/drivers/staging/iio/impedance-analyzer/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for Impedance Converter, Network Analyzer drivers
+#
+
+obj-$(CONFIG_AD5933) += ad5933.o
diff --git a/drivers/staging/iio/impedance-analyzer/ad5933.c b/drivers/staging/iio/impedance-analyzer/ad5933.c
new file mode 100644
index 000000000..b3152f715
--- /dev/null
+++ b/drivers/staging/iio/impedance-analyzer/ad5933.c
@@ -0,0 +1,791 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * AD5933 AD5934 Impedance Converter, Network Analyzer
+ *
+ * Copyright 2011 Analog Devices Inc.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/regulator/consumer.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+
+#include <linux/iio/buffer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/kfifo_buf.h>
+#include <linux/iio/sysfs.h>
+
+/* AD5933/AD5934 Registers */
+#define AD5933_REG_CONTROL_HB		0x80	/* R/W, 1 byte */
+#define AD5933_REG_CONTROL_LB		0x81	/* R/W, 1 byte */
+#define AD5933_REG_FREQ_START		0x82	/* R/W, 3 bytes */
+#define AD5933_REG_FREQ_INC		0x85	/* R/W, 3 bytes */
+#define AD5933_REG_INC_NUM		0x88	/* R/W, 2 bytes, 9 bit */
+#define AD5933_REG_SETTLING_CYCLES	0x8A	/* R/W, 2 bytes */
+#define AD5933_REG_STATUS		0x8F	/* R, 1 byte */
+#define AD5933_REG_TEMP_DATA		0x92	/* R, 2 bytes*/
+#define AD5933_REG_REAL_DATA		0x94	/* R, 2 bytes*/
+#define AD5933_REG_IMAG_DATA		0x96	/* R, 2 bytes*/
+
+/* AD5933_REG_CONTROL_HB Bits */
+#define AD5933_CTRL_INIT_START_FREQ	(0x1 << 4)
+#define AD5933_CTRL_START_SWEEP		(0x2 << 4)
+#define AD5933_CTRL_INC_FREQ		(0x3 << 4)
+#define AD5933_CTRL_REPEAT_FREQ		(0x4 << 4)
+#define AD5933_CTRL_MEASURE_TEMP	(0x9 << 4)
+#define AD5933_CTRL_POWER_DOWN		(0xA << 4)
+#define AD5933_CTRL_STANDBY		(0xB << 4)
+
+#define AD5933_CTRL_RANGE_2000mVpp	(0x0 << 1)
+#define AD5933_CTRL_RANGE_200mVpp	(0x1 << 1)
+#define AD5933_CTRL_RANGE_400mVpp	(0x2 << 1)
+#define AD5933_CTRL_RANGE_1000mVpp	(0x3 << 1)
+#define AD5933_CTRL_RANGE(x)		((x) << 1)
+
+#define AD5933_CTRL_PGA_GAIN_1		(0x1 << 0)
+#define AD5933_CTRL_PGA_GAIN_5		(0x0 << 0)
+
+/* AD5933_REG_CONTROL_LB Bits */
+#define AD5933_CTRL_RESET		(0x1 << 4)
+#define AD5933_CTRL_INT_SYSCLK		(0x0 << 3)
+#define AD5933_CTRL_EXT_SYSCLK		(0x1 << 3)
+
+/* AD5933_REG_STATUS Bits */
+#define AD5933_STAT_TEMP_VALID		(0x1 << 0)
+#define AD5933_STAT_DATA_VALID		(0x1 << 1)
+#define AD5933_STAT_SWEEP_DONE		(0x1 << 2)
+
+/* I2C Block Commands */
+#define AD5933_I2C_BLOCK_WRITE		0xA0
+#define AD5933_I2C_BLOCK_READ		0xA1
+#define AD5933_I2C_ADDR_POINTER		0xB0
+
+/* Device Specs */
+#define AD5933_INT_OSC_FREQ_Hz		16776000
+#define AD5933_MAX_OUTPUT_FREQ_Hz	100000
+#define AD5933_MAX_RETRIES		100
+
+#define AD5933_OUT_RANGE		1
+#define AD5933_OUT_RANGE_AVAIL		2
+#define AD5933_OUT_SETTLING_CYCLES	3
+#define AD5933_IN_PGA_GAIN		4
+#define AD5933_IN_PGA_GAIN_AVAIL	5
+#define AD5933_FREQ_POINTS		6
+
+#define AD5933_POLL_TIME_ms		10
+#define AD5933_INIT_EXCITATION_TIME_ms	100
+
+struct ad5933_state {
+	struct i2c_client		*client;
+	struct regulator		*reg;
+	struct clk			*mclk;
+	struct delayed_work		work;
+	struct mutex			lock; /* Protect sensor state */
+	unsigned long			mclk_hz;
+	unsigned char			ctrl_hb;
+	unsigned char			ctrl_lb;
+	unsigned int			range_avail[4];
+	unsigned short			vref_mv;
+	unsigned short			settling_cycles;
+	unsigned short			freq_points;
+	unsigned int			freq_start;
+	unsigned int			freq_inc;
+	unsigned int			state;
+	unsigned int			poll_time_jiffies;
+};
+
+#define AD5933_CHANNEL(_type, _extend_name, _info_mask_separate, _address, \
+		_scan_index, _realbits) { \
+	.type = (_type), \
+	.extend_name = (_extend_name), \
+	.info_mask_separate = (_info_mask_separate), \
+	.address = (_address), \
+	.scan_index = (_scan_index), \
+	.scan_type = { \
+		.sign = 's', \
+		.realbits = (_realbits), \
+		.storagebits = 16, \
+	}, \
+}
+
+static const struct iio_chan_spec ad5933_channels[] = {
+	AD5933_CHANNEL(IIO_TEMP, NULL, BIT(IIO_CHAN_INFO_RAW) |
+		BIT(IIO_CHAN_INFO_SCALE), AD5933_REG_TEMP_DATA, -1, 14),
+	/* Ring Channels */
+	AD5933_CHANNEL(IIO_VOLTAGE, "real", 0, AD5933_REG_REAL_DATA, 0, 16),
+	AD5933_CHANNEL(IIO_VOLTAGE, "imag", 0, AD5933_REG_IMAG_DATA, 1, 16),
+};
+
+static int ad5933_i2c_write(struct i2c_client *client, u8 reg, u8 len, u8 *data)
+{
+	int ret;
+
+	while (len--) {
+		ret = i2c_smbus_write_byte_data(client, reg++, *data++);
+		if (ret < 0) {
+			dev_err(&client->dev, "I2C write error\n");
+			return ret;
+		}
+	}
+	return 0;
+}
+
+static int ad5933_i2c_read(struct i2c_client *client, u8 reg, u8 len, u8 *data)
+{
+	int ret;
+
+	while (len--) {
+		ret = i2c_smbus_read_byte_data(client, reg++);
+		if (ret < 0) {
+			dev_err(&client->dev, "I2C read error\n");
+			return ret;
+		}
+		*data++ = ret;
+	}
+	return 0;
+}
+
+static int ad5933_cmd(struct ad5933_state *st, unsigned char cmd)
+{
+	unsigned char dat = st->ctrl_hb | cmd;
+
+	return ad5933_i2c_write(st->client,
+			AD5933_REG_CONTROL_HB, 1, &dat);
+}
+
+static int ad5933_reset(struct ad5933_state *st)
+{
+	unsigned char dat = st->ctrl_lb | AD5933_CTRL_RESET;
+
+	return ad5933_i2c_write(st->client,
+			AD5933_REG_CONTROL_LB, 1, &dat);
+}
+
+static int ad5933_wait_busy(struct ad5933_state *st, unsigned char event)
+{
+	unsigned char val, timeout = AD5933_MAX_RETRIES;
+	int ret;
+
+	while (timeout--) {
+		ret =  ad5933_i2c_read(st->client, AD5933_REG_STATUS, 1, &val);
+		if (ret < 0)
+			return ret;
+		if (val & event)
+			return val;
+		cpu_relax();
+		mdelay(1);
+	}
+
+	return -EAGAIN;
+}
+
+static int ad5933_set_freq(struct ad5933_state *st,
+			   unsigned int reg, unsigned long freq)
+{
+	unsigned long long freqreg;
+	union {
+		__be32 d32;
+		u8 d8[4];
+	} dat;
+
+	freqreg = (u64)freq * (u64)(1 << 27);
+	do_div(freqreg, st->mclk_hz / 4);
+
+	switch (reg) {
+	case AD5933_REG_FREQ_START:
+		st->freq_start = freq;
+		break;
+	case AD5933_REG_FREQ_INC:
+		st->freq_inc = freq;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	dat.d32 = cpu_to_be32(freqreg);
+	return ad5933_i2c_write(st->client, reg, 3, &dat.d8[1]);
+}
+
+static int ad5933_setup(struct ad5933_state *st)
+{
+	__be16 dat;
+	int ret;
+
+	ret = ad5933_reset(st);
+	if (ret < 0)
+		return ret;
+
+	ret = ad5933_set_freq(st, AD5933_REG_FREQ_START, 10000);
+	if (ret < 0)
+		return ret;
+
+	ret = ad5933_set_freq(st, AD5933_REG_FREQ_INC, 200);
+	if (ret < 0)
+		return ret;
+
+	st->settling_cycles = 10;
+	dat = cpu_to_be16(st->settling_cycles);
+
+	ret = ad5933_i2c_write(st->client,
+			       AD5933_REG_SETTLING_CYCLES,
+			       2, (u8 *)&dat);
+	if (ret < 0)
+		return ret;
+
+	st->freq_points = 100;
+	dat = cpu_to_be16(st->freq_points);
+
+	return ad5933_i2c_write(st->client, AD5933_REG_INC_NUM, 2, (u8 *)&dat);
+}
+
+static void ad5933_calc_out_ranges(struct ad5933_state *st)
+{
+	int i;
+	unsigned int normalized_3v3[4] = {1980, 198, 383, 970};
+
+	for (i = 0; i < 4; i++)
+		st->range_avail[i] = normalized_3v3[i] * st->vref_mv / 3300;
+}
+
+/*
+ * handles: AD5933_REG_FREQ_START and AD5933_REG_FREQ_INC
+ */
+
+static ssize_t ad5933_show_frequency(struct device *dev,
+				     struct device_attribute *attr,
+				     char *buf)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+	struct ad5933_state *st = iio_priv(indio_dev);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+	int ret;
+	unsigned long long freqreg;
+	union {
+		__be32 d32;
+		u8 d8[4];
+	} dat;
+
+	ret = iio_device_claim_direct_mode(indio_dev);
+	if (ret)
+		return ret;
+	ret = ad5933_i2c_read(st->client, this_attr->address, 3, &dat.d8[1]);
+	iio_device_release_direct_mode(indio_dev);
+	if (ret < 0)
+		return ret;
+
+	freqreg = be32_to_cpu(dat.d32) & 0xFFFFFF;
+
+	freqreg = (u64)freqreg * (u64)(st->mclk_hz / 4);
+	do_div(freqreg, BIT(27));
+
+	return sprintf(buf, "%d\n", (int)freqreg);
+}
+
+static ssize_t ad5933_store_frequency(struct device *dev,
+				      struct device_attribute *attr,
+				      const char *buf,
+				      size_t len)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+	struct ad5933_state *st = iio_priv(indio_dev);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+	unsigned long val;
+	int ret;
+
+	ret = kstrtoul(buf, 10, &val);
+	if (ret)
+		return ret;
+
+	if (val > AD5933_MAX_OUTPUT_FREQ_Hz)
+		return -EINVAL;
+
+	ret = iio_device_claim_direct_mode(indio_dev);
+	if (ret)
+		return ret;
+	ret = ad5933_set_freq(st, this_attr->address, val);
+	iio_device_release_direct_mode(indio_dev);
+
+	return ret ? ret : len;
+}
+
+static IIO_DEVICE_ATTR(out_altvoltage0_frequency_start, 0644,
+			ad5933_show_frequency,
+			ad5933_store_frequency,
+			AD5933_REG_FREQ_START);
+
+static IIO_DEVICE_ATTR(out_altvoltage0_frequency_increment, 0644,
+			ad5933_show_frequency,
+			ad5933_store_frequency,
+			AD5933_REG_FREQ_INC);
+
+static ssize_t ad5933_show(struct device *dev,
+			   struct device_attribute *attr,
+			   char *buf)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+	struct ad5933_state *st = iio_priv(indio_dev);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+	int ret = 0, len = 0;
+
+	mutex_lock(&st->lock);
+	switch ((u32)this_attr->address) {
+	case AD5933_OUT_RANGE:
+		len = sprintf(buf, "%u\n",
+			      st->range_avail[(st->ctrl_hb >> 1) & 0x3]);
+		break;
+	case AD5933_OUT_RANGE_AVAIL:
+		len = sprintf(buf, "%u %u %u %u\n", st->range_avail[0],
+			      st->range_avail[3], st->range_avail[2],
+			      st->range_avail[1]);
+		break;
+	case AD5933_OUT_SETTLING_CYCLES:
+		len = sprintf(buf, "%d\n", st->settling_cycles);
+		break;
+	case AD5933_IN_PGA_GAIN:
+		len = sprintf(buf, "%s\n",
+			      (st->ctrl_hb & AD5933_CTRL_PGA_GAIN_1) ?
+			      "1" : "0.2");
+		break;
+	case AD5933_IN_PGA_GAIN_AVAIL:
+		len = sprintf(buf, "1 0.2\n");
+		break;
+	case AD5933_FREQ_POINTS:
+		len = sprintf(buf, "%d\n", st->freq_points);
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	mutex_unlock(&st->lock);
+	return ret ? ret : len;
+}
+
+static ssize_t ad5933_store(struct device *dev,
+			    struct device_attribute *attr,
+			    const char *buf,
+			    size_t len)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+	struct ad5933_state *st = iio_priv(indio_dev);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+	u16 val;
+	int i, ret = 0;
+	__be16 dat;
+
+	if (this_attr->address != AD5933_IN_PGA_GAIN) {
+		ret = kstrtou16(buf, 10, &val);
+		if (ret)
+			return ret;
+	}
+
+	ret = iio_device_claim_direct_mode(indio_dev);
+	if (ret)
+		return ret;
+	mutex_lock(&st->lock);
+	switch ((u32)this_attr->address) {
+	case AD5933_OUT_RANGE:
+		ret = -EINVAL;
+		for (i = 0; i < 4; i++)
+			if (val == st->range_avail[i]) {
+				st->ctrl_hb &= ~AD5933_CTRL_RANGE(0x3);
+				st->ctrl_hb |= AD5933_CTRL_RANGE(i);
+				ret = ad5933_cmd(st, 0);
+				break;
+			}
+		break;
+	case AD5933_IN_PGA_GAIN:
+		if (sysfs_streq(buf, "1")) {
+			st->ctrl_hb |= AD5933_CTRL_PGA_GAIN_1;
+		} else if (sysfs_streq(buf, "0.2")) {
+			st->ctrl_hb &= ~AD5933_CTRL_PGA_GAIN_1;
+		} else {
+			ret = -EINVAL;
+			break;
+		}
+		ret = ad5933_cmd(st, 0);
+		break;
+	case AD5933_OUT_SETTLING_CYCLES:
+		val = clamp(val, (u16)0, (u16)0x7FF);
+		st->settling_cycles = val;
+
+		/* 2x, 4x handling, see datasheet */
+		if (val > 1022)
+			val = (val >> 2) | (3 << 9);
+		else if (val > 511)
+			val = (val >> 1) | BIT(9);
+
+		dat = cpu_to_be16(val);
+		ret = ad5933_i2c_write(st->client,
+				       AD5933_REG_SETTLING_CYCLES,
+				       2, (u8 *)&dat);
+		break;
+	case AD5933_FREQ_POINTS:
+		val = clamp(val, (u16)0, (u16)511);
+		st->freq_points = val;
+
+		dat = cpu_to_be16(val);
+		ret = ad5933_i2c_write(st->client, AD5933_REG_INC_NUM, 2,
+				       (u8 *)&dat);
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	mutex_unlock(&st->lock);
+	iio_device_release_direct_mode(indio_dev);
+	return ret ? ret : len;
+}
+
+static IIO_DEVICE_ATTR(out_altvoltage0_raw, 0644,
+			ad5933_show,
+			ad5933_store,
+			AD5933_OUT_RANGE);
+
+static IIO_DEVICE_ATTR(out_altvoltage0_scale_available, 0444,
+			ad5933_show,
+			NULL,
+			AD5933_OUT_RANGE_AVAIL);
+
+static IIO_DEVICE_ATTR(in_voltage0_scale, 0644,
+			ad5933_show,
+			ad5933_store,
+			AD5933_IN_PGA_GAIN);
+
+static IIO_DEVICE_ATTR(in_voltage0_scale_available, 0444,
+			ad5933_show,
+			NULL,
+			AD5933_IN_PGA_GAIN_AVAIL);
+
+static IIO_DEVICE_ATTR(out_altvoltage0_frequency_points, 0644,
+			ad5933_show,
+			ad5933_store,
+			AD5933_FREQ_POINTS);
+
+static IIO_DEVICE_ATTR(out_altvoltage0_settling_cycles, 0644,
+			ad5933_show,
+			ad5933_store,
+			AD5933_OUT_SETTLING_CYCLES);
+
+/*
+ * note:
+ * ideally we would handle the scale attributes via the iio_info
+ * (read|write)_raw methods, however this part is a untypical since we
+ * don't create dedicated sysfs channel attributes for out0 and in0.
+ */
+static struct attribute *ad5933_attributes[] = {
+	&iio_dev_attr_out_altvoltage0_raw.dev_attr.attr,
+	&iio_dev_attr_out_altvoltage0_scale_available.dev_attr.attr,
+	&iio_dev_attr_out_altvoltage0_frequency_start.dev_attr.attr,
+	&iio_dev_attr_out_altvoltage0_frequency_increment.dev_attr.attr,
+	&iio_dev_attr_out_altvoltage0_frequency_points.dev_attr.attr,
+	&iio_dev_attr_out_altvoltage0_settling_cycles.dev_attr.attr,
+	&iio_dev_attr_in_voltage0_scale.dev_attr.attr,
+	&iio_dev_attr_in_voltage0_scale_available.dev_attr.attr,
+	NULL
+};
+
+static const struct attribute_group ad5933_attribute_group = {
+	.attrs = ad5933_attributes,
+};
+
+static int ad5933_read_raw(struct iio_dev *indio_dev,
+			   struct iio_chan_spec const *chan,
+			   int *val,
+			   int *val2,
+			   long m)
+{
+	struct ad5933_state *st = iio_priv(indio_dev);
+	__be16 dat;
+	int ret;
+
+	switch (m) {
+	case IIO_CHAN_INFO_RAW:
+		ret = iio_device_claim_direct_mode(indio_dev);
+		if (ret)
+			return ret;
+		ret = ad5933_cmd(st, AD5933_CTRL_MEASURE_TEMP);
+		if (ret < 0)
+			goto out;
+		ret = ad5933_wait_busy(st, AD5933_STAT_TEMP_VALID);
+		if (ret < 0)
+			goto out;
+
+		ret = ad5933_i2c_read(st->client,
+				      AD5933_REG_TEMP_DATA,
+				      2, (u8 *)&dat);
+		if (ret < 0)
+			goto out;
+		iio_device_release_direct_mode(indio_dev);
+		*val = sign_extend32(be16_to_cpu(dat), 13);
+
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_SCALE:
+		*val = 1000;
+		*val2 = 5;
+		return IIO_VAL_FRACTIONAL_LOG2;
+	}
+
+	return -EINVAL;
+out:
+	iio_device_release_direct_mode(indio_dev);
+	return ret;
+}
+
+static const struct iio_info ad5933_info = {
+	.read_raw = ad5933_read_raw,
+	.attrs = &ad5933_attribute_group,
+};
+
+static int ad5933_ring_preenable(struct iio_dev *indio_dev)
+{
+	struct ad5933_state *st = iio_priv(indio_dev);
+	int ret;
+
+	if (bitmap_empty(indio_dev->active_scan_mask, indio_dev->masklength))
+		return -EINVAL;
+
+	ret = ad5933_reset(st);
+	if (ret < 0)
+		return ret;
+
+	ret = ad5933_cmd(st, AD5933_CTRL_STANDBY);
+	if (ret < 0)
+		return ret;
+
+	ret = ad5933_cmd(st, AD5933_CTRL_INIT_START_FREQ);
+	if (ret < 0)
+		return ret;
+
+	st->state = AD5933_CTRL_INIT_START_FREQ;
+
+	return 0;
+}
+
+static int ad5933_ring_postenable(struct iio_dev *indio_dev)
+{
+	struct ad5933_state *st = iio_priv(indio_dev);
+
+	/*
+	 * AD5933_CTRL_INIT_START_FREQ:
+	 * High Q complex circuits require a long time to reach steady state.
+	 * To facilitate the measurement of such impedances, this mode allows
+	 * the user full control of the settling time requirement before
+	 * entering start frequency sweep mode where the impedance measurement
+	 * takes place. In this mode the impedance is excited with the
+	 * programmed start frequency (ad5933_ring_preenable),
+	 * but no measurement takes place.
+	 */
+
+	schedule_delayed_work(&st->work,
+			      msecs_to_jiffies(AD5933_INIT_EXCITATION_TIME_ms));
+	return 0;
+}
+
+static int ad5933_ring_postdisable(struct iio_dev *indio_dev)
+{
+	struct ad5933_state *st = iio_priv(indio_dev);
+
+	cancel_delayed_work_sync(&st->work);
+	return ad5933_cmd(st, AD5933_CTRL_POWER_DOWN);
+}
+
+static const struct iio_buffer_setup_ops ad5933_ring_setup_ops = {
+	.preenable = ad5933_ring_preenable,
+	.postenable = ad5933_ring_postenable,
+	.postdisable = ad5933_ring_postdisable,
+};
+
+static void ad5933_work(struct work_struct *work)
+{
+	struct ad5933_state *st = container_of(work,
+		struct ad5933_state, work.work);
+	struct iio_dev *indio_dev = i2c_get_clientdata(st->client);
+	__be16 buf[2];
+	int val[2];
+	unsigned char status;
+	int ret;
+
+	if (st->state == AD5933_CTRL_INIT_START_FREQ) {
+		/* start sweep */
+		ad5933_cmd(st, AD5933_CTRL_START_SWEEP);
+		st->state = AD5933_CTRL_START_SWEEP;
+		schedule_delayed_work(&st->work, st->poll_time_jiffies);
+		return;
+	}
+
+	ret = ad5933_i2c_read(st->client, AD5933_REG_STATUS, 1, &status);
+	if (ret)
+		return;
+
+	if (status & AD5933_STAT_DATA_VALID) {
+		int scan_count = bitmap_weight(indio_dev->active_scan_mask,
+					       indio_dev->masklength);
+		ret = ad5933_i2c_read(st->client,
+				test_bit(1, indio_dev->active_scan_mask) ?
+				AD5933_REG_REAL_DATA : AD5933_REG_IMAG_DATA,
+				scan_count * 2, (u8 *)buf);
+		if (ret)
+			return;
+
+		if (scan_count == 2) {
+			val[0] = be16_to_cpu(buf[0]);
+			val[1] = be16_to_cpu(buf[1]);
+		} else {
+			val[0] = be16_to_cpu(buf[0]);
+		}
+		iio_push_to_buffers(indio_dev, val);
+	} else {
+		/* no data available - try again later */
+		schedule_delayed_work(&st->work, st->poll_time_jiffies);
+		return;
+	}
+
+	if (status & AD5933_STAT_SWEEP_DONE) {
+		/*
+		 * last sample received - power down do
+		 * nothing until the ring enable is toggled
+		 */
+		ad5933_cmd(st, AD5933_CTRL_POWER_DOWN);
+	} else {
+		/* we just received a valid datum, move on to the next */
+		ad5933_cmd(st, AD5933_CTRL_INC_FREQ);
+		schedule_delayed_work(&st->work, st->poll_time_jiffies);
+	}
+}
+
+static void ad5933_reg_disable(void *data)
+{
+	struct ad5933_state *st = data;
+
+	regulator_disable(st->reg);
+}
+
+static void ad5933_clk_disable(void *data)
+{
+	struct ad5933_state *st = data;
+
+	clk_disable_unprepare(st->mclk);
+}
+
+static int ad5933_probe(struct i2c_client *client)
+{
+	const struct i2c_device_id *id = i2c_client_get_device_id(client);
+	int ret;
+	struct ad5933_state *st;
+	struct iio_dev *indio_dev;
+	unsigned long ext_clk_hz = 0;
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	st = iio_priv(indio_dev);
+	i2c_set_clientdata(client, indio_dev);
+	st->client = client;
+
+	mutex_init(&st->lock);
+
+	st->reg = devm_regulator_get(&client->dev, "vdd");
+	if (IS_ERR(st->reg))
+		return PTR_ERR(st->reg);
+
+	ret = regulator_enable(st->reg);
+	if (ret) {
+		dev_err(&client->dev, "Failed to enable specified VDD supply\n");
+		return ret;
+	}
+
+	ret = devm_add_action_or_reset(&client->dev, ad5933_reg_disable, st);
+	if (ret)
+		return ret;
+
+	ret = regulator_get_voltage(st->reg);
+	if (ret < 0)
+		return ret;
+
+	st->vref_mv = ret / 1000;
+
+	st->mclk = devm_clk_get(&client->dev, "mclk");
+	if (IS_ERR(st->mclk) && PTR_ERR(st->mclk) != -ENOENT)
+		return PTR_ERR(st->mclk);
+
+	if (!IS_ERR(st->mclk)) {
+		ret = clk_prepare_enable(st->mclk);
+		if (ret < 0)
+			return ret;
+
+		ret = devm_add_action_or_reset(&client->dev,
+					       ad5933_clk_disable,
+					       st);
+		if (ret)
+			return ret;
+
+		ext_clk_hz = clk_get_rate(st->mclk);
+	}
+
+	if (ext_clk_hz) {
+		st->mclk_hz = ext_clk_hz;
+		st->ctrl_lb = AD5933_CTRL_EXT_SYSCLK;
+	} else {
+		st->mclk_hz = AD5933_INT_OSC_FREQ_Hz;
+		st->ctrl_lb = AD5933_CTRL_INT_SYSCLK;
+	}
+
+	ad5933_calc_out_ranges(st);
+	INIT_DELAYED_WORK(&st->work, ad5933_work);
+	st->poll_time_jiffies = msecs_to_jiffies(AD5933_POLL_TIME_ms);
+
+	indio_dev->info = &ad5933_info;
+	indio_dev->name = id->name;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = ad5933_channels;
+	indio_dev->num_channels = ARRAY_SIZE(ad5933_channels);
+
+	ret = devm_iio_kfifo_buffer_setup(&client->dev, indio_dev,
+					  &ad5933_ring_setup_ops);
+	if (ret)
+		return ret;
+
+	ret = ad5933_setup(st);
+	if (ret)
+		return ret;
+
+	return devm_iio_device_register(&client->dev, indio_dev);
+}
+
+static const struct i2c_device_id ad5933_id[] = {
+	{ "ad5933", 0 },
+	{ "ad5934", 0 },
+	{}
+};
+
+MODULE_DEVICE_TABLE(i2c, ad5933_id);
+
+static const struct of_device_id ad5933_of_match[] = {
+	{ .compatible = "adi,ad5933" },
+	{ .compatible = "adi,ad5934" },
+	{ },
+};
+
+MODULE_DEVICE_TABLE(of, ad5933_of_match);
+
+static struct i2c_driver ad5933_driver = {
+	.driver = {
+		.name = "ad5933",
+		.of_match_table = ad5933_of_match,
+	},
+	.probe_new = ad5933_probe,
+	.id_table = ad5933_id,
+};
+module_i2c_driver(ad5933_driver);
+
+MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
+MODULE_DESCRIPTION("Analog Devices AD5933 Impedance Conv. Network Analyzer");
+MODULE_LICENSE("GPL v2");