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, 595 insertions, 0 deletions

diff --git a/drivers/hwmon/tps23861.c b/drivers/hwmon/tps23861.c
new file mode 100644
index 000000000..68c77c493
--- /dev/null
+++ b/drivers/hwmon/tps23861.c
@@ -0,0 +1,595 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2020 Sartura Ltd.
+ *
+ * Driver for the TI TPS23861 PoE PSE.
+ *
+ * Author: Robert Marko <robert.marko@sartura.hr>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/debugfs.h>
+#include <linux/delay.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/hwmon.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+
+#define TEMPERATURE			0x2c
+#define INPUT_VOLTAGE_LSB		0x2e
+#define INPUT_VOLTAGE_MSB		0x2f
+#define PORT_1_CURRENT_LSB		0x30
+#define PORT_1_CURRENT_MSB		0x31
+#define PORT_1_VOLTAGE_LSB		0x32
+#define PORT_1_VOLTAGE_MSB		0x33
+#define PORT_2_CURRENT_LSB		0x34
+#define PORT_2_CURRENT_MSB		0x35
+#define PORT_2_VOLTAGE_LSB		0x36
+#define PORT_2_VOLTAGE_MSB		0x37
+#define PORT_3_CURRENT_LSB		0x38
+#define PORT_3_CURRENT_MSB		0x39
+#define PORT_3_VOLTAGE_LSB		0x3a
+#define PORT_3_VOLTAGE_MSB		0x3b
+#define PORT_4_CURRENT_LSB		0x3c
+#define PORT_4_CURRENT_MSB		0x3d
+#define PORT_4_VOLTAGE_LSB		0x3e
+#define PORT_4_VOLTAGE_MSB		0x3f
+#define PORT_N_CURRENT_LSB_OFFSET	0x04
+#define PORT_N_VOLTAGE_LSB_OFFSET	0x04
+#define VOLTAGE_CURRENT_MASK		GENMASK(13, 0)
+#define PORT_1_RESISTANCE_LSB		0x60
+#define PORT_1_RESISTANCE_MSB		0x61
+#define PORT_2_RESISTANCE_LSB		0x62
+#define PORT_2_RESISTANCE_MSB		0x63
+#define PORT_3_RESISTANCE_LSB		0x64
+#define PORT_3_RESISTANCE_MSB		0x65
+#define PORT_4_RESISTANCE_LSB		0x66
+#define PORT_4_RESISTANCE_MSB		0x67
+#define PORT_N_RESISTANCE_LSB_OFFSET	0x02
+#define PORT_RESISTANCE_MASK		GENMASK(13, 0)
+#define PORT_RESISTANCE_RSN_MASK	GENMASK(15, 14)
+#define PORT_RESISTANCE_RSN_OTHER	0
+#define PORT_RESISTANCE_RSN_LOW		1
+#define PORT_RESISTANCE_RSN_OPEN	2
+#define PORT_RESISTANCE_RSN_SHORT	3
+#define PORT_1_STATUS			0x0c
+#define PORT_2_STATUS			0x0d
+#define PORT_3_STATUS			0x0e
+#define PORT_4_STATUS			0x0f
+#define PORT_STATUS_CLASS_MASK		GENMASK(7, 4)
+#define PORT_STATUS_DETECT_MASK		GENMASK(3, 0)
+#define PORT_CLASS_UNKNOWN		0
+#define PORT_CLASS_1			1
+#define PORT_CLASS_2			2
+#define PORT_CLASS_3			3
+#define PORT_CLASS_4			4
+#define PORT_CLASS_RESERVED		5
+#define PORT_CLASS_0			6
+#define PORT_CLASS_OVERCURRENT		7
+#define PORT_CLASS_MISMATCH		8
+#define PORT_DETECT_UNKNOWN		0
+#define PORT_DETECT_SHORT		1
+#define PORT_DETECT_RESERVED		2
+#define PORT_DETECT_RESISTANCE_LOW	3
+#define PORT_DETECT_RESISTANCE_OK	4
+#define PORT_DETECT_RESISTANCE_HIGH	5
+#define PORT_DETECT_OPEN_CIRCUIT	6
+#define PORT_DETECT_RESERVED_2		7
+#define PORT_DETECT_MOSFET_FAULT	8
+#define PORT_DETECT_LEGACY		9
+/* Measurment beyond clamp voltage */
+#define PORT_DETECT_CAPACITANCE_INVALID_BEYOND	10
+/* Insufficient voltage delta */
+#define PORT_DETECT_CAPACITANCE_INVALID_DELTA	11
+#define PORT_DETECT_CAPACITANCE_OUT_OF_RANGE	12
+#define POE_PLUS			0x40
+#define OPERATING_MODE			0x12
+#define OPERATING_MODE_OFF		0
+#define OPERATING_MODE_MANUAL		1
+#define OPERATING_MODE_SEMI		2
+#define OPERATING_MODE_AUTO		3
+#define OPERATING_MODE_PORT_1_MASK	GENMASK(1, 0)
+#define OPERATING_MODE_PORT_2_MASK	GENMASK(3, 2)
+#define OPERATING_MODE_PORT_3_MASK	GENMASK(5, 4)
+#define OPERATING_MODE_PORT_4_MASK	GENMASK(7, 6)
+
+#define DETECT_CLASS_RESTART		0x18
+#define POWER_ENABLE			0x19
+#define TPS23861_NUM_PORTS		4
+
+#define TPS23861_GENERAL_MASK_1		0x17
+#define TPS23861_CURRENT_SHUNT_MASK	BIT(0)
+
+#define TEMPERATURE_LSB			652 /* 0.652 degrees Celsius */
+#define VOLTAGE_LSB			3662 /* 3.662 mV */
+#define SHUNT_RESISTOR_DEFAULT		255000 /* 255 mOhm */
+#define CURRENT_LSB_250			62260 /* 62.260 uA */
+#define CURRENT_LSB_255			61039 /* 61.039 uA */
+#define RESISTANCE_LSB			110966 /* 11.0966 Ohm*/
+#define RESISTANCE_LSB_LOW		157216 /* 15.7216 Ohm*/
+
+struct tps23861_data {
+	struct regmap *regmap;
+	u32 shunt_resistor;
+	struct i2c_client *client;
+	struct dentry *debugfs_dir;
+};
+
+static struct regmap_config tps23861_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = 0x6f,
+};
+
+static int tps23861_read_temp(struct tps23861_data *data, long *val)
+{
+	unsigned int regval;
+	int err;
+
+	err = regmap_read(data->regmap, TEMPERATURE, &regval);
+	if (err < 0)
+		return err;
+
+	*val = (regval * TEMPERATURE_LSB) - 20000;
+
+	return 0;
+}
+
+static int tps23861_read_voltage(struct tps23861_data *data, int channel,
+				 long *val)
+{
+	__le16 regval;
+	long raw_val;
+	int err;
+
+	if (channel < TPS23861_NUM_PORTS) {
+		err = regmap_bulk_read(data->regmap,
+				       PORT_1_VOLTAGE_LSB + channel * PORT_N_VOLTAGE_LSB_OFFSET,
+				       &regval, 2);
+	} else {
+		err = regmap_bulk_read(data->regmap,
+				       INPUT_VOLTAGE_LSB,
+				       &regval, 2);
+	}
+	if (err < 0)
+		return err;
+
+	raw_val = le16_to_cpu(regval);
+	*val = (FIELD_GET(VOLTAGE_CURRENT_MASK, raw_val) * VOLTAGE_LSB) / 1000;
+
+	return 0;
+}
+
+static int tps23861_read_current(struct tps23861_data *data, int channel,
+				 long *val)
+{
+	long raw_val, current_lsb;
+	__le16 regval;
+
+	int err;
+
+	if (data->shunt_resistor == SHUNT_RESISTOR_DEFAULT)
+		current_lsb = CURRENT_LSB_255;
+	else
+		current_lsb = CURRENT_LSB_250;
+
+	err = regmap_bulk_read(data->regmap,
+			       PORT_1_CURRENT_LSB + channel * PORT_N_CURRENT_LSB_OFFSET,
+			       &regval, 2);
+	if (err < 0)
+		return err;
+
+	raw_val = le16_to_cpu(regval);
+	*val = (FIELD_GET(VOLTAGE_CURRENT_MASK, raw_val) * current_lsb) / 1000000;
+
+	return 0;
+}
+
+static int tps23861_port_disable(struct tps23861_data *data, int channel)
+{
+	unsigned int regval = 0;
+	int err;
+
+	regval |= BIT(channel + 4);
+	err = regmap_write(data->regmap, POWER_ENABLE, regval);
+
+	return err;
+}
+
+static int tps23861_port_enable(struct tps23861_data *data, int channel)
+{
+	unsigned int regval = 0;
+	int err;
+
+	regval |= BIT(channel);
+	regval |= BIT(channel + 4);
+	err = regmap_write(data->regmap, DETECT_CLASS_RESTART, regval);
+
+	return err;
+}
+
+static umode_t tps23861_is_visible(const void *data, enum hwmon_sensor_types type,
+				   u32 attr, int channel)
+{
+	switch (type) {
+	case hwmon_temp:
+		switch (attr) {
+		case hwmon_temp_input:
+		case hwmon_temp_label:
+			return 0444;
+		default:
+			return 0;
+		}
+	case hwmon_in:
+		switch (attr) {
+		case hwmon_in_input:
+		case hwmon_in_label:
+			return 0444;
+		case hwmon_in_enable:
+			return 0200;
+		default:
+			return 0;
+		}
+	case hwmon_curr:
+		switch (attr) {
+		case hwmon_curr_input:
+		case hwmon_curr_label:
+			return 0444;
+		default:
+			return 0;
+		}
+	default:
+		return 0;
+	}
+}
+
+static int tps23861_write(struct device *dev, enum hwmon_sensor_types type,
+			  u32 attr, int channel, long val)
+{
+	struct tps23861_data *data = dev_get_drvdata(dev);
+	int err;
+
+	switch (type) {
+	case hwmon_in:
+		switch (attr) {
+		case hwmon_in_enable:
+			if (val == 0)
+				err = tps23861_port_disable(data, channel);
+			else if (val == 1)
+				err = tps23861_port_enable(data, channel);
+			else
+				err = -EINVAL;
+			break;
+		default:
+			return -EOPNOTSUPP;
+		}
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return err;
+}
+
+static int tps23861_read(struct device *dev, enum hwmon_sensor_types type,
+			 u32 attr, int channel, long *val)
+{
+	struct tps23861_data *data = dev_get_drvdata(dev);
+	int err;
+
+	switch (type) {
+	case hwmon_temp:
+		switch (attr) {
+		case hwmon_temp_input:
+			err = tps23861_read_temp(data, val);
+			break;
+		default:
+			return -EOPNOTSUPP;
+		}
+		break;
+	case hwmon_in:
+		switch (attr) {
+		case hwmon_in_input:
+			err = tps23861_read_voltage(data, channel, val);
+			break;
+		default:
+			return -EOPNOTSUPP;
+		}
+		break;
+	case hwmon_curr:
+		switch (attr) {
+		case hwmon_curr_input:
+			err = tps23861_read_current(data, channel, val);
+			break;
+		default:
+			return -EOPNOTSUPP;
+		}
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return err;
+}
+
+static const char * const tps23861_port_label[] = {
+	"Port1",
+	"Port2",
+	"Port3",
+	"Port4",
+	"Input",
+};
+
+static int tps23861_read_string(struct device *dev,
+				enum hwmon_sensor_types type,
+				u32 attr, int channel, const char **str)
+{
+	switch (type) {
+	case hwmon_in:
+	case hwmon_curr:
+		*str = tps23861_port_label[channel];
+		break;
+	case hwmon_temp:
+		*str = "Die";
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
+
+static const struct hwmon_channel_info *tps23861_info[] = {
+	HWMON_CHANNEL_INFO(chip,
+			   HWMON_C_REGISTER_TZ),
+	HWMON_CHANNEL_INFO(temp,
+			   HWMON_T_INPUT | HWMON_T_LABEL),
+	HWMON_CHANNEL_INFO(in,
+			   HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_LABEL),
+	HWMON_CHANNEL_INFO(curr,
+			   HWMON_C_INPUT | HWMON_C_LABEL,
+			   HWMON_C_INPUT | HWMON_C_LABEL,
+			   HWMON_C_INPUT | HWMON_C_LABEL,
+			   HWMON_C_INPUT | HWMON_C_LABEL),
+	NULL
+};
+
+static const struct hwmon_ops tps23861_hwmon_ops = {
+	.is_visible = tps23861_is_visible,
+	.write = tps23861_write,
+	.read = tps23861_read,
+	.read_string = tps23861_read_string,
+};
+
+static const struct hwmon_chip_info tps23861_chip_info = {
+	.ops = &tps23861_hwmon_ops,
+	.info = tps23861_info,
+};
+
+static char *port_operating_mode_string(uint8_t mode_reg, unsigned int port)
+{
+	unsigned int mode = ~0;
+
+	if (port < TPS23861_NUM_PORTS)
+		mode = (mode_reg >> (2 * port)) & OPERATING_MODE_PORT_1_MASK;
+
+	switch (mode) {
+	case OPERATING_MODE_OFF:
+		return "Off";
+	case OPERATING_MODE_MANUAL:
+		return "Manual";
+	case OPERATING_MODE_SEMI:
+		return "Semi-Auto";
+	case OPERATING_MODE_AUTO:
+		return "Auto";
+	default:
+		return "Invalid";
+	}
+}
+
+static char *port_detect_status_string(uint8_t status_reg)
+{
+	switch (FIELD_GET(PORT_STATUS_DETECT_MASK, status_reg)) {
+	case PORT_DETECT_UNKNOWN:
+		return "Unknown device";
+	case PORT_DETECT_SHORT:
+		return "Short circuit";
+	case PORT_DETECT_RESISTANCE_LOW:
+		return "Too low resistance";
+	case PORT_DETECT_RESISTANCE_OK:
+		return "Valid resistance";
+	case PORT_DETECT_RESISTANCE_HIGH:
+		return "Too high resistance";
+	case PORT_DETECT_OPEN_CIRCUIT:
+		return "Open circuit";
+	case PORT_DETECT_MOSFET_FAULT:
+		return "MOSFET fault";
+	case PORT_DETECT_LEGACY:
+		return "Legacy device";
+	case PORT_DETECT_CAPACITANCE_INVALID_BEYOND:
+		return "Invalid capacitance, beyond clamp voltage";
+	case PORT_DETECT_CAPACITANCE_INVALID_DELTA:
+		return "Invalid capacitance, insufficient voltage delta";
+	case PORT_DETECT_CAPACITANCE_OUT_OF_RANGE:
+		return "Valid capacitance, outside of legacy range";
+	case PORT_DETECT_RESERVED:
+	case PORT_DETECT_RESERVED_2:
+	default:
+		return "Invalid";
+	}
+}
+
+static char *port_class_status_string(uint8_t status_reg)
+{
+	switch (FIELD_GET(PORT_STATUS_CLASS_MASK, status_reg)) {
+	case PORT_CLASS_UNKNOWN:
+		return "Unknown";
+	case PORT_CLASS_RESERVED:
+	case PORT_CLASS_0:
+		return "0";
+	case PORT_CLASS_1:
+		return "1";
+	case PORT_CLASS_2:
+		return "2";
+	case PORT_CLASS_3:
+		return "3";
+	case PORT_CLASS_4:
+		return "4";
+	case PORT_CLASS_OVERCURRENT:
+		return "Overcurrent";
+	case PORT_CLASS_MISMATCH:
+		return "Mismatch";
+	default:
+		return "Invalid";
+	}
+}
+
+static char *port_poe_plus_status_string(uint8_t poe_plus, unsigned int port)
+{
+	return (BIT(port + 4) & poe_plus) ? "Yes" : "No";
+}
+
+static int tps23861_port_resistance(struct tps23861_data *data, int port)
+{
+	unsigned int raw_val;
+	__le16 regval;
+
+	regmap_bulk_read(data->regmap,
+			 PORT_1_RESISTANCE_LSB + PORT_N_RESISTANCE_LSB_OFFSET * port,
+			 &regval,
+			 2);
+
+	raw_val = le16_to_cpu(regval);
+	switch (FIELD_GET(PORT_RESISTANCE_RSN_MASK, raw_val)) {
+	case PORT_RESISTANCE_RSN_OTHER:
+		return (FIELD_GET(PORT_RESISTANCE_MASK, raw_val) * RESISTANCE_LSB) / 10000;
+	case PORT_RESISTANCE_RSN_LOW:
+		return (FIELD_GET(PORT_RESISTANCE_MASK, raw_val) * RESISTANCE_LSB_LOW) / 10000;
+	case PORT_RESISTANCE_RSN_SHORT:
+	case PORT_RESISTANCE_RSN_OPEN:
+	default:
+		return 0;
+	}
+}
+
+static int tps23861_port_status_show(struct seq_file *s, void *data)
+{
+	struct tps23861_data *priv = s->private;
+	unsigned int i, mode, poe_plus, status;
+
+	regmap_read(priv->regmap, OPERATING_MODE, &mode);
+	regmap_read(priv->regmap, POE_PLUS, &poe_plus);
+
+	for (i = 0; i < TPS23861_NUM_PORTS; i++) {
+		regmap_read(priv->regmap, PORT_1_STATUS + i, &status);
+
+		seq_printf(s, "Port: \t\t%d\n", i + 1);
+		seq_printf(s, "Operating mode: %s\n", port_operating_mode_string(mode, i));
+		seq_printf(s, "Detected: \t%s\n", port_detect_status_string(status));
+		seq_printf(s, "Class: \t\t%s\n", port_class_status_string(status));
+		seq_printf(s, "PoE Plus: \t%s\n", port_poe_plus_status_string(poe_plus, i));
+		seq_printf(s, "Resistance: \t%d\n", tps23861_port_resistance(priv, i));
+		seq_putc(s, '\n');
+	}
+
+	return 0;
+}
+
+DEFINE_SHOW_ATTRIBUTE(tps23861_port_status);
+
+static void tps23861_init_debugfs(struct tps23861_data *data,
+				  struct device *hwmon_dev)
+{
+	const char *debugfs_name;
+
+	debugfs_name = devm_kasprintf(&data->client->dev, GFP_KERNEL, "%s-%s",
+				      data->client->name, dev_name(hwmon_dev));
+	if (!debugfs_name)
+		return;
+
+	data->debugfs_dir = debugfs_create_dir(debugfs_name, NULL);
+
+	debugfs_create_file("port_status",
+			    0400,
+			    data->debugfs_dir,
+			    data,
+			    &tps23861_port_status_fops);
+}
+
+static int tps23861_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct tps23861_data *data;
+	struct device *hwmon_dev;
+	u32 shunt_resistor;
+
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->client = client;
+	i2c_set_clientdata(client, data);
+
+	data->regmap = devm_regmap_init_i2c(client, &tps23861_regmap_config);
+	if (IS_ERR(data->regmap)) {
+		dev_err(dev, "failed to allocate register map\n");
+		return PTR_ERR(data->regmap);
+	}
+
+	if (!of_property_read_u32(dev->of_node, "shunt-resistor-micro-ohms", &shunt_resistor))
+		data->shunt_resistor = shunt_resistor;
+	else
+		data->shunt_resistor = SHUNT_RESISTOR_DEFAULT;
+
+	if (data->shunt_resistor == SHUNT_RESISTOR_DEFAULT)
+		regmap_clear_bits(data->regmap,
+				  TPS23861_GENERAL_MASK_1,
+				  TPS23861_CURRENT_SHUNT_MASK);
+	else
+		regmap_set_bits(data->regmap,
+				TPS23861_GENERAL_MASK_1,
+				TPS23861_CURRENT_SHUNT_MASK);
+
+	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
+							 data, &tps23861_chip_info,
+							 NULL);
+	if (IS_ERR(hwmon_dev))
+		return PTR_ERR(hwmon_dev);
+
+	tps23861_init_debugfs(data, hwmon_dev);
+
+	return 0;
+}
+
+static void tps23861_remove(struct i2c_client *client)
+{
+	struct tps23861_data *data = i2c_get_clientdata(client);
+
+	debugfs_remove_recursive(data->debugfs_dir);
+}
+
+static const struct of_device_id __maybe_unused tps23861_of_match[] = {
+	{ .compatible = "ti,tps23861", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, tps23861_of_match);
+
+static struct i2c_driver tps23861_driver = {
+	.probe_new		= tps23861_probe,
+	.remove			= tps23861_remove,
+	.driver = {
+		.name		= "tps23861",
+		.of_match_table	= of_match_ptr(tps23861_of_match),
+	},
+};
+module_i2c_driver(tps23861_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Robert Marko <robert.marko@sartura.hr>");
+MODULE_DESCRIPTION("TI TPS23861 PoE PSE");