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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/hwmon/ltc4215.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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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(). ...
Diffstat (limited to 'drivers/hwmon/ltc4215.c')
-rw-r--r--drivers/hwmon/ltc4215.c266
1 files changed, 266 insertions, 0 deletions
diff --git a/drivers/hwmon/ltc4215.c b/drivers/hwmon/ltc4215.c
new file mode 100644
index 000000000..fa43d26dd
--- /dev/null
+++ b/drivers/hwmon/ltc4215.c
@@ -0,0 +1,266 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Driver for Linear Technology LTC4215 I2C Hot Swap Controller
+ *
+ * Copyright (C) 2009 Ira W. Snyder <iws@ovro.caltech.edu>
+ *
+ * Datasheet:
+ * http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1003,C1006,C1163,P17572,D12697
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/jiffies.h>
+
+/* Here are names of the chip's registers (a.k.a. commands) */
+enum ltc4215_cmd {
+ LTC4215_CONTROL = 0x00, /* rw */
+ LTC4215_ALERT = 0x01, /* rw */
+ LTC4215_STATUS = 0x02, /* ro */
+ LTC4215_FAULT = 0x03, /* rw */
+ LTC4215_SENSE = 0x04, /* rw */
+ LTC4215_SOURCE = 0x05, /* rw */
+ LTC4215_ADIN = 0x06, /* rw */
+};
+
+struct ltc4215_data {
+ struct i2c_client *client;
+
+ struct mutex update_lock;
+ bool valid;
+ unsigned long last_updated; /* in jiffies */
+
+ /* Registers */
+ u8 regs[7];
+};
+
+static struct ltc4215_data *ltc4215_update_device(struct device *dev)
+{
+ struct ltc4215_data *data = dev_get_drvdata(dev);
+ struct i2c_client *client = data->client;
+ s32 val;
+ int i;
+
+ mutex_lock(&data->update_lock);
+
+ /* The chip's A/D updates 10 times per second */
+ if (time_after(jiffies, data->last_updated + HZ / 10) || !data->valid) {
+
+ dev_dbg(&client->dev, "Starting ltc4215 update\n");
+
+ /* Read all registers */
+ for (i = 0; i < ARRAY_SIZE(data->regs); i++) {
+ val = i2c_smbus_read_byte_data(client, i);
+ if (unlikely(val < 0))
+ data->regs[i] = 0;
+ else
+ data->regs[i] = val;
+ }
+
+ data->last_updated = jiffies;
+ data->valid = true;
+ }
+
+ mutex_unlock(&data->update_lock);
+
+ return data;
+}
+
+/* Return the voltage from the given register in millivolts */
+static int ltc4215_get_voltage(struct device *dev, u8 reg)
+{
+ struct ltc4215_data *data = ltc4215_update_device(dev);
+ const u8 regval = data->regs[reg];
+ u32 voltage = 0;
+
+ switch (reg) {
+ case LTC4215_SENSE:
+ /* 151 uV per increment */
+ voltage = regval * 151 / 1000;
+ break;
+ case LTC4215_SOURCE:
+ /* 60.5 mV per increment */
+ voltage = regval * 605 / 10;
+ break;
+ case LTC4215_ADIN:
+ /*
+ * The ADIN input is divided by 12.5, and has 4.82 mV
+ * per increment, so we have the additional multiply
+ */
+ voltage = regval * 482 * 125 / 1000;
+ break;
+ default:
+ /* If we get here, the developer messed up */
+ WARN_ON_ONCE(1);
+ break;
+ }
+
+ return voltage;
+}
+
+/* Return the current from the sense resistor in mA */
+static unsigned int ltc4215_get_current(struct device *dev)
+{
+ struct ltc4215_data *data = ltc4215_update_device(dev);
+
+ /*
+ * The strange looking conversions that follow are fixed-point
+ * math, since we cannot do floating point in the kernel.
+ *
+ * Step 1: convert sense register to microVolts
+ * Step 2: convert voltage to milliAmperes
+ *
+ * If you play around with the V=IR equation, you come up with
+ * the following: X uV / Y mOhm == Z mA
+ *
+ * With the resistors that are fractions of a milliOhm, we multiply
+ * the voltage and resistance by 10, to shift the decimal point.
+ * Now we can use the normal division operator again.
+ */
+
+ /* Calculate voltage in microVolts (151 uV per increment) */
+ const unsigned int voltage = data->regs[LTC4215_SENSE] * 151;
+
+ /* Calculate current in milliAmperes (4 milliOhm sense resistor) */
+ const unsigned int curr = voltage / 4;
+
+ return curr;
+}
+
+static ssize_t ltc4215_voltage_show(struct device *dev,
+ struct device_attribute *da, char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+ const int voltage = ltc4215_get_voltage(dev, attr->index);
+
+ return sysfs_emit(buf, "%d\n", voltage);
+}
+
+static ssize_t ltc4215_current_show(struct device *dev,
+ struct device_attribute *da, char *buf)
+{
+ const unsigned int curr = ltc4215_get_current(dev);
+
+ return sysfs_emit(buf, "%u\n", curr);
+}
+
+static ssize_t ltc4215_power_show(struct device *dev,
+ struct device_attribute *da, char *buf)
+{
+ const unsigned int curr = ltc4215_get_current(dev);
+ const int output_voltage = ltc4215_get_voltage(dev, LTC4215_ADIN);
+
+ /* current in mA * voltage in mV == power in uW */
+ const unsigned int power = abs(output_voltage * curr);
+
+ return sysfs_emit(buf, "%u\n", power);
+}
+
+static ssize_t ltc4215_alarm_show(struct device *dev,
+ struct device_attribute *da, char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+ struct ltc4215_data *data = ltc4215_update_device(dev);
+ const u8 reg = data->regs[LTC4215_STATUS];
+ const u32 mask = attr->index;
+
+ return sysfs_emit(buf, "%u\n", !!(reg & mask));
+}
+
+/*
+ * These macros are used below in constructing device attribute objects
+ * for use with sysfs_create_group() to make a sysfs device file
+ * for each register.
+ */
+
+/* Construct a sensor_device_attribute structure for each register */
+
+/* Current */
+static SENSOR_DEVICE_ATTR_RO(curr1_input, ltc4215_current, 0);
+static SENSOR_DEVICE_ATTR_RO(curr1_max_alarm, ltc4215_alarm, 1 << 2);
+
+/* Power (virtual) */
+static SENSOR_DEVICE_ATTR_RO(power1_input, ltc4215_power, 0);
+
+/* Input Voltage */
+static SENSOR_DEVICE_ATTR_RO(in1_input, ltc4215_voltage, LTC4215_ADIN);
+static SENSOR_DEVICE_ATTR_RO(in1_max_alarm, ltc4215_alarm, 1 << 0);
+static SENSOR_DEVICE_ATTR_RO(in1_min_alarm, ltc4215_alarm, 1 << 1);
+
+/* Output Voltage */
+static SENSOR_DEVICE_ATTR_RO(in2_input, ltc4215_voltage, LTC4215_SOURCE);
+static SENSOR_DEVICE_ATTR_RO(in2_min_alarm, ltc4215_alarm, 1 << 3);
+
+/*
+ * Finally, construct an array of pointers to members of the above objects,
+ * as required for sysfs_create_group()
+ */
+static struct attribute *ltc4215_attrs[] = {
+ &sensor_dev_attr_curr1_input.dev_attr.attr,
+ &sensor_dev_attr_curr1_max_alarm.dev_attr.attr,
+
+ &sensor_dev_attr_power1_input.dev_attr.attr,
+
+ &sensor_dev_attr_in1_input.dev_attr.attr,
+ &sensor_dev_attr_in1_max_alarm.dev_attr.attr,
+ &sensor_dev_attr_in1_min_alarm.dev_attr.attr,
+
+ &sensor_dev_attr_in2_input.dev_attr.attr,
+ &sensor_dev_attr_in2_min_alarm.dev_attr.attr,
+
+ NULL,
+};
+ATTRIBUTE_GROUPS(ltc4215);
+
+static int ltc4215_probe(struct i2c_client *client)
+{
+ struct i2c_adapter *adapter = client->adapter;
+ struct device *dev = &client->dev;
+ struct ltc4215_data *data;
+ struct device *hwmon_dev;
+
+ if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
+ return -ENODEV;
+
+ data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->client = client;
+ mutex_init(&data->update_lock);
+
+ /* Initialize the LTC4215 chip */
+ i2c_smbus_write_byte_data(client, LTC4215_FAULT, 0x00);
+
+ hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
+ data,
+ ltc4215_groups);
+ return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+static const struct i2c_device_id ltc4215_id[] = {
+ { "ltc4215", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ltc4215_id);
+
+/* This is the driver that will be inserted */
+static struct i2c_driver ltc4215_driver = {
+ .driver = {
+ .name = "ltc4215",
+ },
+ .probe_new = ltc4215_probe,
+ .id_table = ltc4215_id,
+};
+
+module_i2c_driver(ltc4215_driver);
+
+MODULE_AUTHOR("Ira W. Snyder <iws@ovro.caltech.edu>");
+MODULE_DESCRIPTION("LTC4215 driver");
+MODULE_LICENSE("GPL");