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, 755 insertions, 0 deletions

diff --git a/drivers/hwmon/sht3x.c b/drivers/hwmon/sht3x.c
new file mode 100644
index 000000000..8305e44d9
--- /dev/null
+++ b/drivers/hwmon/sht3x.c
@@ -0,0 +1,755 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* Sensirion SHT3x-DIS humidity and temperature sensor driver.
+ * The SHT3x comes in many different versions, this driver is for the
+ * I2C version only.
+ *
+ * Copyright (C) 2016 Sensirion AG, Switzerland
+ * Author: David Frey <david.frey@sensirion.com>
+ * Author: Pascal Sachs <pascal.sachs@sensirion.com>
+ */
+
+#include <asm/page.h>
+#include <linux/crc8.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/jiffies.h>
+#include <linux/platform_data/sht3x.h>
+
+/* commands (high precision mode) */
+static const unsigned char sht3x_cmd_measure_blocking_hpm[]    = { 0x2c, 0x06 };
+static const unsigned char sht3x_cmd_measure_nonblocking_hpm[] = { 0x24, 0x00 };
+
+/* commands (low power mode) */
+static const unsigned char sht3x_cmd_measure_blocking_lpm[]    = { 0x2c, 0x10 };
+static const unsigned char sht3x_cmd_measure_nonblocking_lpm[] = { 0x24, 0x16 };
+
+/* commands for periodic mode */
+static const unsigned char sht3x_cmd_measure_periodic_mode[]   = { 0xe0, 0x00 };
+static const unsigned char sht3x_cmd_break[]                   = { 0x30, 0x93 };
+
+/* commands for heater control */
+static const unsigned char sht3x_cmd_heater_on[]               = { 0x30, 0x6d };
+static const unsigned char sht3x_cmd_heater_off[]              = { 0x30, 0x66 };
+
+/* other commands */
+static const unsigned char sht3x_cmd_read_status_reg[]         = { 0xf3, 0x2d };
+static const unsigned char sht3x_cmd_clear_status_reg[]        = { 0x30, 0x41 };
+
+/* delays for non-blocking i2c commands, both in us */
+#define SHT3X_NONBLOCKING_WAIT_TIME_HPM  15000
+#define SHT3X_NONBLOCKING_WAIT_TIME_LPM   4000
+
+#define SHT3X_WORD_LEN         2
+#define SHT3X_CMD_LENGTH       2
+#define SHT3X_CRC8_LEN         1
+#define SHT3X_RESPONSE_LENGTH  6
+#define SHT3X_CRC8_POLYNOMIAL  0x31
+#define SHT3X_CRC8_INIT        0xFF
+#define SHT3X_MIN_TEMPERATURE  -45000
+#define SHT3X_MAX_TEMPERATURE  130000
+#define SHT3X_MIN_HUMIDITY     0
+#define SHT3X_MAX_HUMIDITY     100000
+
+enum sht3x_chips {
+	sht3x,
+	sts3x,
+};
+
+enum sht3x_limits {
+	limit_max = 0,
+	limit_max_hyst,
+	limit_min,
+	limit_min_hyst,
+};
+
+DECLARE_CRC8_TABLE(sht3x_crc8_table);
+
+/* periodic measure commands (high precision mode) */
+static const char periodic_measure_commands_hpm[][SHT3X_CMD_LENGTH] = {
+	/* 0.5 measurements per second */
+	{0x20, 0x32},
+	/* 1 measurements per second */
+	{0x21, 0x30},
+	/* 2 measurements per second */
+	{0x22, 0x36},
+	/* 4 measurements per second */
+	{0x23, 0x34},
+	/* 10 measurements per second */
+	{0x27, 0x37},
+};
+
+/* periodic measure commands (low power mode) */
+static const char periodic_measure_commands_lpm[][SHT3X_CMD_LENGTH] = {
+	/* 0.5 measurements per second */
+	{0x20, 0x2f},
+	/* 1 measurements per second */
+	{0x21, 0x2d},
+	/* 2 measurements per second */
+	{0x22, 0x2b},
+	/* 4 measurements per second */
+	{0x23, 0x29},
+	/* 10 measurements per second */
+	{0x27, 0x2a},
+};
+
+struct sht3x_limit_commands {
+	const char read_command[SHT3X_CMD_LENGTH];
+	const char write_command[SHT3X_CMD_LENGTH];
+};
+
+static const struct sht3x_limit_commands limit_commands[] = {
+	/* temp1_max, humidity1_max */
+	[limit_max] = { {0xe1, 0x1f}, {0x61, 0x1d} },
+	/* temp_1_max_hyst, humidity1_max_hyst */
+	[limit_max_hyst] = { {0xe1, 0x14}, {0x61, 0x16} },
+	/* temp1_min, humidity1_min */
+	[limit_min] = { {0xe1, 0x02}, {0x61, 0x00} },
+	/* temp_1_min_hyst, humidity1_min_hyst */
+	[limit_min_hyst] = { {0xe1, 0x09}, {0x61, 0x0B} },
+};
+
+#define SHT3X_NUM_LIMIT_CMD  ARRAY_SIZE(limit_commands)
+
+static const u16 mode_to_update_interval[] = {
+	   0,
+	2000,
+	1000,
+	 500,
+	 250,
+	 100,
+};
+
+struct sht3x_data {
+	struct i2c_client *client;
+	struct mutex i2c_lock; /* lock for sending i2c commands */
+	struct mutex data_lock; /* lock for updating driver data */
+
+	u8 mode;
+	const unsigned char *command;
+	u32 wait_time;			/* in us*/
+	unsigned long last_update;	/* last update in periodic mode*/
+
+	struct sht3x_platform_data setup;
+
+	/*
+	 * cached values for temperature and humidity and limits
+	 * the limits arrays have the following order:
+	 * max, max_hyst, min, min_hyst
+	 */
+	int temperature;
+	int temperature_limits[SHT3X_NUM_LIMIT_CMD];
+	u32 humidity;
+	u32 humidity_limits[SHT3X_NUM_LIMIT_CMD];
+};
+
+static u8 get_mode_from_update_interval(u16 value)
+{
+	size_t index;
+	u8 number_of_modes = ARRAY_SIZE(mode_to_update_interval);
+
+	if (value == 0)
+		return 0;
+
+	/* find next faster update interval */
+	for (index = 1; index < number_of_modes; index++) {
+		if (mode_to_update_interval[index] <= value)
+			return index;
+	}
+
+	return number_of_modes - 1;
+}
+
+static int sht3x_read_from_command(struct i2c_client *client,
+				   struct sht3x_data *data,
+				   const char *command,
+				   char *buf, int length, u32 wait_time)
+{
+	int ret;
+
+	mutex_lock(&data->i2c_lock);
+	ret = i2c_master_send(client, command, SHT3X_CMD_LENGTH);
+
+	if (ret != SHT3X_CMD_LENGTH) {
+		ret = ret < 0 ? ret : -EIO;
+		goto out;
+	}
+
+	if (wait_time)
+		usleep_range(wait_time, wait_time + 1000);
+
+	ret = i2c_master_recv(client, buf, length);
+	if (ret != length) {
+		ret = ret < 0 ? ret : -EIO;
+		goto out;
+	}
+
+	ret = 0;
+out:
+	mutex_unlock(&data->i2c_lock);
+	return ret;
+}
+
+static int sht3x_extract_temperature(u16 raw)
+{
+	/*
+	 * From datasheet:
+	 * T = -45 + 175 * ST / 2^16
+	 * Adapted for integer fixed point (3 digit) arithmetic.
+	 */
+	return ((21875 * (int)raw) >> 13) - 45000;
+}
+
+static u32 sht3x_extract_humidity(u16 raw)
+{
+	/*
+	 * From datasheet:
+	 * RH = 100 * SRH / 2^16
+	 * Adapted for integer fixed point (3 digit) arithmetic.
+	 */
+	return (12500 * (u32)raw) >> 13;
+}
+
+static struct sht3x_data *sht3x_update_client(struct device *dev)
+{
+	struct sht3x_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	u16 interval_ms = mode_to_update_interval[data->mode];
+	unsigned long interval_jiffies = msecs_to_jiffies(interval_ms);
+	unsigned char buf[SHT3X_RESPONSE_LENGTH];
+	u16 val;
+	int ret = 0;
+
+	mutex_lock(&data->data_lock);
+	/*
+	 * Only update cached readings once per update interval in periodic
+	 * mode. In single shot mode the sensor measures values on demand, so
+	 * every time the sysfs interface is called, a measurement is triggered.
+	 * In periodic mode however, the measurement process is handled
+	 * internally by the sensor and reading out sensor values only makes
+	 * sense if a new reading is available.
+	 */
+	if (time_after(jiffies, data->last_update + interval_jiffies)) {
+		ret = sht3x_read_from_command(client, data, data->command, buf,
+					      sizeof(buf), data->wait_time);
+		if (ret)
+			goto out;
+
+		val = be16_to_cpup((__be16 *)buf);
+		data->temperature = sht3x_extract_temperature(val);
+		val = be16_to_cpup((__be16 *)(buf + 3));
+		data->humidity = sht3x_extract_humidity(val);
+		data->last_update = jiffies;
+	}
+
+out:
+	mutex_unlock(&data->data_lock);
+	if (ret)
+		return ERR_PTR(ret);
+
+	return data;
+}
+
+/* sysfs attributes */
+static ssize_t temp1_input_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct sht3x_data *data = sht3x_update_client(dev);
+
+	if (IS_ERR(data))
+		return PTR_ERR(data);
+
+	return sprintf(buf, "%d\n", data->temperature);
+}
+
+static ssize_t humidity1_input_show(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	struct sht3x_data *data = sht3x_update_client(dev);
+
+	if (IS_ERR(data))
+		return PTR_ERR(data);
+
+	return sprintf(buf, "%u\n", data->humidity);
+}
+
+/*
+ * limits_update must only be called from probe or with data_lock held
+ */
+static int limits_update(struct sht3x_data *data)
+{
+	int ret;
+	u8 index;
+	int temperature;
+	u32 humidity;
+	u16 raw;
+	char buffer[SHT3X_RESPONSE_LENGTH];
+	const struct sht3x_limit_commands *commands;
+	struct i2c_client *client = data->client;
+
+	for (index = 0; index < SHT3X_NUM_LIMIT_CMD; index++) {
+		commands = &limit_commands[index];
+		ret = sht3x_read_from_command(client, data,
+					      commands->read_command, buffer,
+					      SHT3X_RESPONSE_LENGTH, 0);
+
+		if (ret)
+			return ret;
+
+		raw = be16_to_cpup((__be16 *)buffer);
+		temperature = sht3x_extract_temperature((raw & 0x01ff) << 7);
+		humidity = sht3x_extract_humidity(raw & 0xfe00);
+		data->temperature_limits[index] = temperature;
+		data->humidity_limits[index] = humidity;
+	}
+
+	return ret;
+}
+
+static ssize_t temp1_limit_show(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
+{
+	struct sht3x_data *data = dev_get_drvdata(dev);
+	u8 index = to_sensor_dev_attr(attr)->index;
+	int temperature_limit = data->temperature_limits[index];
+
+	return sysfs_emit(buf, "%d\n", temperature_limit);
+}
+
+static ssize_t humidity1_limit_show(struct device *dev,
+				    struct device_attribute *attr,
+				    char *buf)
+{
+	struct sht3x_data *data = dev_get_drvdata(dev);
+	u8 index = to_sensor_dev_attr(attr)->index;
+	u32 humidity_limit = data->humidity_limits[index];
+
+	return sysfs_emit(buf, "%u\n", humidity_limit);
+}
+
+/*
+ * limit_store must only be called with data_lock held
+ */
+static size_t limit_store(struct device *dev,
+			  size_t count,
+			  u8 index,
+			  int temperature,
+			  u32 humidity)
+{
+	char buffer[SHT3X_CMD_LENGTH + SHT3X_WORD_LEN + SHT3X_CRC8_LEN];
+	char *position = buffer;
+	int ret;
+	u16 raw;
+	struct sht3x_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	const struct sht3x_limit_commands *commands;
+
+	commands = &limit_commands[index];
+
+	memcpy(position, commands->write_command, SHT3X_CMD_LENGTH);
+	position += SHT3X_CMD_LENGTH;
+	/*
+	 * ST = (T + 45) / 175 * 2^16
+	 * SRH = RH / 100 * 2^16
+	 * adapted for fixed point arithmetic and packed the same as
+	 * in limit_show()
+	 */
+	raw = ((u32)(temperature + 45000) * 24543) >> (16 + 7);
+	raw |= ((humidity * 42950) >> 16) & 0xfe00;
+
+	*((__be16 *)position) = cpu_to_be16(raw);
+	position += SHT3X_WORD_LEN;
+	*position = crc8(sht3x_crc8_table,
+			 position - SHT3X_WORD_LEN,
+			 SHT3X_WORD_LEN,
+			 SHT3X_CRC8_INIT);
+
+	mutex_lock(&data->i2c_lock);
+	ret = i2c_master_send(client, buffer, sizeof(buffer));
+	mutex_unlock(&data->i2c_lock);
+
+	if (ret != sizeof(buffer))
+		return ret < 0 ? ret : -EIO;
+
+	data->temperature_limits[index] = temperature;
+	data->humidity_limits[index] = humidity;
+	return count;
+}
+
+static ssize_t temp1_limit_store(struct device *dev,
+				 struct device_attribute *attr,
+				 const char *buf,
+				 size_t count)
+{
+	int temperature;
+	int ret;
+	struct sht3x_data *data = dev_get_drvdata(dev);
+	u8 index = to_sensor_dev_attr(attr)->index;
+
+	ret = kstrtoint(buf, 0, &temperature);
+	if (ret)
+		return ret;
+
+	temperature = clamp_val(temperature, SHT3X_MIN_TEMPERATURE,
+				SHT3X_MAX_TEMPERATURE);
+	mutex_lock(&data->data_lock);
+	ret = limit_store(dev, count, index, temperature,
+			  data->humidity_limits[index]);
+	mutex_unlock(&data->data_lock);
+
+	return ret;
+}
+
+static ssize_t humidity1_limit_store(struct device *dev,
+				     struct device_attribute *attr,
+				     const char *buf,
+				     size_t count)
+{
+	u32 humidity;
+	int ret;
+	struct sht3x_data *data = dev_get_drvdata(dev);
+	u8 index = to_sensor_dev_attr(attr)->index;
+
+	ret = kstrtou32(buf, 0, &humidity);
+	if (ret)
+		return ret;
+
+	humidity = clamp_val(humidity, SHT3X_MIN_HUMIDITY, SHT3X_MAX_HUMIDITY);
+	mutex_lock(&data->data_lock);
+	ret = limit_store(dev, count, index, data->temperature_limits[index],
+			  humidity);
+	mutex_unlock(&data->data_lock);
+
+	return ret;
+}
+
+static void sht3x_select_command(struct sht3x_data *data)
+{
+	/*
+	 * In blocking mode (clock stretching mode) the I2C bus
+	 * is blocked for other traffic, thus the call to i2c_master_recv()
+	 * will wait until the data is ready. For non blocking mode, we
+	 * have to wait ourselves.
+	 */
+	if (data->mode > 0) {
+		data->command = sht3x_cmd_measure_periodic_mode;
+		data->wait_time = 0;
+	} else if (data->setup.blocking_io) {
+		data->command = data->setup.high_precision ?
+				sht3x_cmd_measure_blocking_hpm :
+				sht3x_cmd_measure_blocking_lpm;
+		data->wait_time = 0;
+	} else {
+		if (data->setup.high_precision) {
+			data->command = sht3x_cmd_measure_nonblocking_hpm;
+			data->wait_time = SHT3X_NONBLOCKING_WAIT_TIME_HPM;
+		} else {
+			data->command = sht3x_cmd_measure_nonblocking_lpm;
+			data->wait_time = SHT3X_NONBLOCKING_WAIT_TIME_LPM;
+		}
+	}
+}
+
+static int status_register_read(struct device *dev,
+				struct device_attribute *attr,
+				char *buffer, int length)
+{
+	int ret;
+	struct sht3x_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+
+	ret = sht3x_read_from_command(client, data, sht3x_cmd_read_status_reg,
+				      buffer, length, 0);
+
+	return ret;
+}
+
+static ssize_t temp1_alarm_show(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
+{
+	char buffer[SHT3X_WORD_LEN + SHT3X_CRC8_LEN];
+	int ret;
+
+	ret = status_register_read(dev, attr, buffer,
+				   SHT3X_WORD_LEN + SHT3X_CRC8_LEN);
+	if (ret)
+		return ret;
+
+	return sysfs_emit(buf, "%d\n", !!(buffer[0] & 0x04));
+}
+
+static ssize_t humidity1_alarm_show(struct device *dev,
+				    struct device_attribute *attr,
+				    char *buf)
+{
+	char buffer[SHT3X_WORD_LEN + SHT3X_CRC8_LEN];
+	int ret;
+
+	ret = status_register_read(dev, attr, buffer,
+				   SHT3X_WORD_LEN + SHT3X_CRC8_LEN);
+	if (ret)
+		return ret;
+
+	return sysfs_emit(buf, "%d\n", !!(buffer[0] & 0x08));
+}
+
+static ssize_t heater_enable_show(struct device *dev,
+				  struct device_attribute *attr,
+				  char *buf)
+{
+	char buffer[SHT3X_WORD_LEN + SHT3X_CRC8_LEN];
+	int ret;
+
+	ret = status_register_read(dev, attr, buffer,
+				   SHT3X_WORD_LEN + SHT3X_CRC8_LEN);
+	if (ret)
+		return ret;
+
+	return sysfs_emit(buf, "%d\n", !!(buffer[0] & 0x20));
+}
+
+static ssize_t heater_enable_store(struct device *dev,
+				   struct device_attribute *attr,
+				   const char *buf,
+				   size_t count)
+{
+	struct sht3x_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	int ret;
+	bool status;
+
+	ret = kstrtobool(buf, &status);
+	if (ret)
+		return ret;
+
+	mutex_lock(&data->i2c_lock);
+
+	if (status)
+		ret = i2c_master_send(client, (char *)&sht3x_cmd_heater_on,
+				      SHT3X_CMD_LENGTH);
+	else
+		ret = i2c_master_send(client, (char *)&sht3x_cmd_heater_off,
+				      SHT3X_CMD_LENGTH);
+
+	mutex_unlock(&data->i2c_lock);
+
+	return ret;
+}
+
+static ssize_t update_interval_show(struct device *dev,
+				    struct device_attribute *attr,
+				    char *buf)
+{
+	struct sht3x_data *data = dev_get_drvdata(dev);
+
+	return sysfs_emit(buf, "%u\n",
+			 mode_to_update_interval[data->mode]);
+}
+
+static ssize_t update_interval_store(struct device *dev,
+				     struct device_attribute *attr,
+				     const char *buf,
+				     size_t count)
+{
+	u16 update_interval;
+	u8 mode;
+	int ret;
+	const char *command;
+	struct sht3x_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+
+	ret = kstrtou16(buf, 0, &update_interval);
+	if (ret)
+		return ret;
+
+	mode = get_mode_from_update_interval(update_interval);
+
+	mutex_lock(&data->data_lock);
+	/* mode did not change */
+	if (mode == data->mode) {
+		mutex_unlock(&data->data_lock);
+		return count;
+	}
+
+	mutex_lock(&data->i2c_lock);
+	/*
+	 * Abort periodic measure mode.
+	 * To do any changes to the configuration while in periodic mode, we
+	 * have to send a break command to the sensor, which then falls back
+	 * to single shot (mode = 0).
+	 */
+	if (data->mode > 0) {
+		ret = i2c_master_send(client, sht3x_cmd_break,
+				      SHT3X_CMD_LENGTH);
+		if (ret != SHT3X_CMD_LENGTH)
+			goto out;
+		data->mode = 0;
+	}
+
+	if (mode > 0) {
+		if (data->setup.high_precision)
+			command = periodic_measure_commands_hpm[mode - 1];
+		else
+			command = periodic_measure_commands_lpm[mode - 1];
+
+		/* select mode */
+		ret = i2c_master_send(client, command, SHT3X_CMD_LENGTH);
+		if (ret != SHT3X_CMD_LENGTH)
+			goto out;
+	}
+
+	/* select mode and command */
+	data->mode = mode;
+	sht3x_select_command(data);
+
+out:
+	mutex_unlock(&data->i2c_lock);
+	mutex_unlock(&data->data_lock);
+	if (ret != SHT3X_CMD_LENGTH)
+		return ret < 0 ? ret : -EIO;
+
+	return count;
+}
+
+static SENSOR_DEVICE_ATTR_RO(temp1_input, temp1_input, 0);
+static SENSOR_DEVICE_ATTR_RO(humidity1_input, humidity1_input, 0);
+static SENSOR_DEVICE_ATTR_RW(temp1_max, temp1_limit, limit_max);
+static SENSOR_DEVICE_ATTR_RW(humidity1_max, humidity1_limit, limit_max);
+static SENSOR_DEVICE_ATTR_RW(temp1_max_hyst, temp1_limit, limit_max_hyst);
+static SENSOR_DEVICE_ATTR_RW(humidity1_max_hyst, humidity1_limit,
+			     limit_max_hyst);
+static SENSOR_DEVICE_ATTR_RW(temp1_min, temp1_limit, limit_min);
+static SENSOR_DEVICE_ATTR_RW(humidity1_min, humidity1_limit, limit_min);
+static SENSOR_DEVICE_ATTR_RW(temp1_min_hyst, temp1_limit, limit_min_hyst);
+static SENSOR_DEVICE_ATTR_RW(humidity1_min_hyst, humidity1_limit,
+			     limit_min_hyst);
+static SENSOR_DEVICE_ATTR_RO(temp1_alarm, temp1_alarm, 0);
+static SENSOR_DEVICE_ATTR_RO(humidity1_alarm, humidity1_alarm, 0);
+static SENSOR_DEVICE_ATTR_RW(heater_enable, heater_enable, 0);
+static SENSOR_DEVICE_ATTR_RW(update_interval, update_interval, 0);
+
+static struct attribute *sht3x_attrs[] = {
+	&sensor_dev_attr_temp1_input.dev_attr.attr,
+	&sensor_dev_attr_humidity1_input.dev_attr.attr,
+	&sensor_dev_attr_temp1_max.dev_attr.attr,
+	&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
+	&sensor_dev_attr_humidity1_max.dev_attr.attr,
+	&sensor_dev_attr_humidity1_max_hyst.dev_attr.attr,
+	&sensor_dev_attr_temp1_min.dev_attr.attr,
+	&sensor_dev_attr_temp1_min_hyst.dev_attr.attr,
+	&sensor_dev_attr_humidity1_min.dev_attr.attr,
+	&sensor_dev_attr_humidity1_min_hyst.dev_attr.attr,
+	&sensor_dev_attr_temp1_alarm.dev_attr.attr,
+	&sensor_dev_attr_humidity1_alarm.dev_attr.attr,
+	&sensor_dev_attr_heater_enable.dev_attr.attr,
+	&sensor_dev_attr_update_interval.dev_attr.attr,
+	NULL
+};
+
+static struct attribute *sts3x_attrs[] = {
+	&sensor_dev_attr_temp1_input.dev_attr.attr,
+	NULL
+};
+
+ATTRIBUTE_GROUPS(sht3x);
+ATTRIBUTE_GROUPS(sts3x);
+
+static const struct i2c_device_id sht3x_ids[];
+
+static int sht3x_probe(struct i2c_client *client)
+{
+	int ret;
+	struct sht3x_data *data;
+	struct device *hwmon_dev;
+	struct i2c_adapter *adap = client->adapter;
+	struct device *dev = &client->dev;
+	const struct attribute_group **attribute_groups;
+
+	/*
+	 * we require full i2c support since the sht3x uses multi-byte read and
+	 * writes as well as multi-byte commands which are not supported by
+	 * the smbus protocol
+	 */
+	if (!i2c_check_functionality(adap, I2C_FUNC_I2C))
+		return -ENODEV;
+
+	ret = i2c_master_send(client, sht3x_cmd_clear_status_reg,
+			      SHT3X_CMD_LENGTH);
+	if (ret != SHT3X_CMD_LENGTH)
+		return ret < 0 ? ret : -ENODEV;
+
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->setup.blocking_io = false;
+	data->setup.high_precision = true;
+	data->mode = 0;
+	data->last_update = jiffies - msecs_to_jiffies(3000);
+	data->client = client;
+	crc8_populate_msb(sht3x_crc8_table, SHT3X_CRC8_POLYNOMIAL);
+
+	if (client->dev.platform_data)
+		data->setup = *(struct sht3x_platform_data *)dev->platform_data;
+
+	sht3x_select_command(data);
+
+	mutex_init(&data->i2c_lock);
+	mutex_init(&data->data_lock);
+
+	/*
+	 * An attempt to read limits register too early
+	 * causes a NACK response from the chip.
+	 * Waiting for an empirical delay of 500 us solves the issue.
+	 */
+	usleep_range(500, 600);
+
+	ret = limits_update(data);
+	if (ret)
+		return ret;
+
+	if (i2c_match_id(sht3x_ids, client)->driver_data == sts3x)
+		attribute_groups = sts3x_groups;
+	else
+		attribute_groups = sht3x_groups;
+
+	hwmon_dev = devm_hwmon_device_register_with_groups(dev,
+							   client->name,
+							   data,
+							   attribute_groups);
+
+	if (IS_ERR(hwmon_dev))
+		dev_dbg(dev, "unable to register hwmon device\n");
+
+	return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+/* device ID table */
+static const struct i2c_device_id sht3x_ids[] = {
+	{"sht3x", sht3x},
+	{"sts3x", sts3x},
+	{}
+};
+
+MODULE_DEVICE_TABLE(i2c, sht3x_ids);
+
+static struct i2c_driver sht3x_i2c_driver = {
+	.driver.name = "sht3x",
+	.probe_new   = sht3x_probe,
+	.id_table    = sht3x_ids,
+};
+
+module_i2c_driver(sht3x_i2c_driver);
+
+MODULE_AUTHOR("David Frey <david.frey@sensirion.com>");
+MODULE_AUTHOR("Pascal Sachs <pascal.sachs@sensirion.com>");
+MODULE_DESCRIPTION("Sensirion SHT3x humidity and temperature sensor driver");
+MODULE_LICENSE("GPL");