diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-30 09:22:00 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-30 09:22:00 -0700 |
| commit | 034dd340b08be1f2f0477ad16131d609f9dbd53c (patch) | |
| tree | 2536f4b2d7893ccd916b5abdf3c454ad6edc03c2 /drivers/hwmon/ltc2945.c | |
| download | linux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.tar.gz linux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.zip | |
Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted
Pull tracing fixes from Steven Rostedt:
- Fix error output of boot instance creation failure
Currently if a boot instance creation fails, instead of printing out
the name of the instance that failed, it prints "(null)". That is
because it prints "cur_str" that had already been processed by
strsep(). Print the saved name instead.
While at it, print the error code of the failure.
- Fix use-after-free for same named historgrams
Histograms can be named so that they can be used in multiple events.
But if the named histogram has a variable attached, the second event
that uses the named histogram which duplicates it and needs to free
the original after duplication leaves the old variable in place and
still visible. If another histogram uses than variable, it will use
the stale one which will try to reference the freed duplicate
histogram and crash the kernel.
Free the duplicate variables along with the duplicated histogram
data.
- Check return value of kthread_run() in event self test
The events self tests uses a kthread for testing but does not check
if it succeeded in creating a kthread. If the kthread creation were
to fail, the code will still try to call kthread_stop() on the error
returned.
- Fix race between reading trace_pipe and updating subbuffer size
If a user is reading the trace_pipe file at the same time they update
the ring buffer sub-buffer size, can cause the trace_pipe read to
read stale data. Add trace_access_lock() around updating the ring
buffer sub-buffer size.
- Fix eventfs_inode on failure path in creation of the events directory
In the creation of the "events" directory, if after allocating the
eventfs_inode a failure is detected, it calls cleanup_ei() which
calls free_ei(). The free_ei() will test if eventfs_inode being freed
has no children. It is a bug if it does. But on the failure case of
the creation of the "events" directory, the children lists have not
yet been initialized and the free will trigger a warning because
list_empty() on an uninitialized list returns false.
Move the initialization into init_ei() where it makes more sense and
makes sure that a created eventfs_inode has its lists initialized
upon creation.
- Check return value of kthread_run() in ftrace direct sample code
The sample code that shows how to use the ftrace direct calls does
not test the return of kthread_run() to see if it succeeds. Return a
failure if the kthread_run() doesn't succeed.
- Clear user events state on fork in case of alloc failure
On fork, the child gets a pointer to the parent's user events state.
It makes a copy of it then updates the child's pointer to it. But if
the allocation fails, the duplication function leaves the child with
a pointer to its parent's descriptor. When the child cleans up its
data, it will free the parent's descriptor while the parent is still
using it.
In the duplication function, set the child's user_event_mm to NULL
before testing if the allocation succeeded, and when it exits it will
not free the parent's descriptor.
- Fix retry exhaustion in simple ring buffer reader swap
simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
post-decrements it only after a failed link replacement. On the final
attempt, a successful replacement leaves retry at zero, while a
failed replacement leaves it at -1.
But the check for success expects the retry value to be non-zero and
exits with an error on zero. This is the opposite result. Fix it.
- Fail nicely when the remote swap_reader_page() returns an error
Currently, if the swap_reader_page() of a remote buffer fails, it
triggers a WARN_ON_ONCE() and continues normally. Instead, have it
exit with an error and a pr_warn() print instead of a full WARNING.
* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
ring-buffer: Stop remote reader update when page swap fails
tracing: Fix retry exhaustion in simple ring buffer reader swap
tracing/user_events: Clear copied tracing state before fork duplication
samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
eventfs: Initialize ei->children and ei->list in init_ei()
tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
tracing: Fix crash passing ERR_PTR to kthread_stop()
tracing: Fix use-after-free with same-name named triggers
tracing: Fix logged instance name on creation failure
Diffstat (limited to 'drivers/hwmon/ltc2945.c')
| -rw-r--r-- | drivers/hwmon/ltc2945.c | 530 |
1 files changed, 530 insertions, 0 deletions
diff --git a/drivers/hwmon/ltc2945.c b/drivers/hwmon/ltc2945.c new file mode 100644 index 000000000..b521100af --- /dev/null +++ b/drivers/hwmon/ltc2945.c @@ -0,0 +1,530 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Driver for Linear Technology LTC2945 I2C Power Monitor + * + * Copyright (c) 2014 Guenter Roeck + */ + +#include <linux/kernel.h> +#include <linux/module.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> +#include <linux/regmap.h> + +/* chip registers */ +#define LTC2945_CONTROL 0x00 +#define LTC2945_ALERT 0x01 +#define LTC2945_STATUS 0x02 +#define LTC2945_FAULT 0x03 +#define LTC2945_POWER_H 0x05 +#define LTC2945_MAX_POWER_H 0x08 +#define LTC2945_MIN_POWER_H 0x0b +#define LTC2945_MAX_POWER_THRES_H 0x0e +#define LTC2945_MIN_POWER_THRES_H 0x11 +#define LTC2945_SENSE_H 0x14 +#define LTC2945_MAX_SENSE_H 0x16 +#define LTC2945_MIN_SENSE_H 0x18 +#define LTC2945_MAX_SENSE_THRES_H 0x1a +#define LTC2945_MIN_SENSE_THRES_H 0x1c +#define LTC2945_VIN_H 0x1e +#define LTC2945_MAX_VIN_H 0x20 +#define LTC2945_MIN_VIN_H 0x22 +#define LTC2945_MAX_VIN_THRES_H 0x24 +#define LTC2945_MIN_VIN_THRES_H 0x26 +#define LTC2945_ADIN_H 0x28 +#define LTC2945_MAX_ADIN_H 0x2a +#define LTC2945_MIN_ADIN_H 0x2c +#define LTC2945_MAX_ADIN_THRES_H 0x2e +#define LTC2945_MIN_ADIN_THRES_H 0x30 +#define LTC2945_MIN_ADIN_THRES_L 0x31 + +/* Fault register bits */ + +#define FAULT_ADIN_UV (1 << 0) +#define FAULT_ADIN_OV (1 << 1) +#define FAULT_VIN_UV (1 << 2) +#define FAULT_VIN_OV (1 << 3) +#define FAULT_SENSE_UV (1 << 4) +#define FAULT_SENSE_OV (1 << 5) +#define FAULT_POWER_UV (1 << 6) +#define FAULT_POWER_OV (1 << 7) + +/* Control register bits */ + +#define CONTROL_MULT_SELECT (1 << 0) +#define CONTROL_TEST_MODE (1 << 4) + +static const struct of_device_id __maybe_unused ltc2945_of_match[] = { + { .compatible = "adi,ltc2945" }, + { } +}; +MODULE_DEVICE_TABLE(of, ltc2945_of_match); + +/** + * struct ltc2945_data - LTC2945 device data + * @regmap: regmap device + * @shunt_resistor: shunt resistor value in micro ohms (1000 by default) + */ +struct ltc2945_data { + struct regmap *regmap; + u32 shunt_resistor; +}; + +static inline bool is_power_reg(u8 reg) +{ + return reg < LTC2945_SENSE_H; +} + +/* Return the value from the given register in uW, mV, or mA */ +static long long ltc2945_reg_to_val(struct device *dev, u8 reg) +{ + struct ltc2945_data *data = dev_get_drvdata(dev); + struct regmap *regmap = data->regmap; + u32 shunt_resistor = data->shunt_resistor; + unsigned int control; + u8 buf[3]; + long long val; + int ret; + + ret = regmap_bulk_read(regmap, reg, buf, + is_power_reg(reg) ? 3 : 2); + if (ret < 0) + return ret; + + if (is_power_reg(reg)) { + /* 24-bit power */ + val = (buf[0] << 16) + (buf[1] << 8) + buf[2]; + } else { + /* 12-bit current, voltage */ + val = (buf[0] << 4) + (buf[1] >> 4); + } + + switch (reg) { + case LTC2945_POWER_H: + case LTC2945_MAX_POWER_H: + case LTC2945_MIN_POWER_H: + case LTC2945_MAX_POWER_THRES_H: + case LTC2945_MIN_POWER_THRES_H: + /* + * Convert to uW + * Control register bit 0 selects if voltage at SENSE+/VDD + * or voltage at ADIN is used to measure power. + */ + ret = regmap_read(regmap, LTC2945_CONTROL, &control); + if (ret < 0) + return ret; + if (control & CONTROL_MULT_SELECT) { + /* 25 mV * 25 uV = 0.625 uV resolution. */ + val *= 625LL; + } else { + /* 0.5 mV * 25 uV = 0.0125 uV resolution. */ + val = (val * 25LL) >> 1; + } + val *= 1000; + /* Overflow check: Assuming max 24-bit power, val is at most 53 bits right now. */ + val = DIV_ROUND_CLOSEST_ULL(val, shunt_resistor); + /* + * Overflow check: After division, depending on shunt resistor, + * val can still be > 32 bits so returning long long makes sense + */ + + break; + case LTC2945_VIN_H: + case LTC2945_MAX_VIN_H: + case LTC2945_MIN_VIN_H: + case LTC2945_MAX_VIN_THRES_H: + case LTC2945_MIN_VIN_THRES_H: + /* 25 mV resolution. Convert to mV. */ + val *= 25; + break; + case LTC2945_ADIN_H: + case LTC2945_MAX_ADIN_H: + case LTC2945_MIN_ADIN_THRES_H: + case LTC2945_MAX_ADIN_THRES_H: + case LTC2945_MIN_ADIN_H: + /* 0.5mV resolution. Convert to mV. */ + val = val >> 1; + break; + case LTC2945_SENSE_H: + case LTC2945_MAX_SENSE_H: + case LTC2945_MIN_SENSE_H: + case LTC2945_MAX_SENSE_THRES_H: + case LTC2945_MIN_SENSE_THRES_H: + /* 25 uV resolution. Convert to mA. */ + val *= 25 * 1000; + /* Overflow check: Assuming max 12-bit sense, val is at most 27 bits right now */ + val = DIV_ROUND_CLOSEST_ULL(val, shunt_resistor); + /* Overflow check: After division, <= 27 bits */ + break; + default: + return -EINVAL; + } + return val; +} + +static long long ltc2945_val_to_reg(struct device *dev, u8 reg, + unsigned long long val) +{ + struct ltc2945_data *data = dev_get_drvdata(dev); + struct regmap *regmap = data->regmap; + u32 shunt_resistor = data->shunt_resistor; + unsigned int control; + int ret; + + /* Ensure we don't overflow */ + val = clamp_val(val, 0, U32_MAX); + + switch (reg) { + case LTC2945_POWER_H: + case LTC2945_MAX_POWER_H: + case LTC2945_MIN_POWER_H: + case LTC2945_MAX_POWER_THRES_H: + case LTC2945_MIN_POWER_THRES_H: + /* + * Control register bit 0 selects if voltage at SENSE+/VDD + * or voltage at ADIN is used to measure power, which in turn + * determines register calculations. + */ + ret = regmap_read(regmap, LTC2945_CONTROL, &control); + if (ret < 0) + return ret; + if (control & CONTROL_MULT_SELECT) { + /* 25 mV * 25 uV = 0.625 uV resolution. */ + val *= shunt_resistor; + /* Overflow check: Assuming 32-bit val and shunt resistor, val <= 64bits */ + val = DIV_ROUND_CLOSEST_ULL(val, 625 * 1000); + /* Overflow check: val is now <= 44 bits */ + } else { + /* 0.5 mV * 25 uV = 0.0125 uV resolution. */ + val *= shunt_resistor; + /* Overflow check: Assuming 32-bit val and shunt resistor, val <= 64bits */ + val = DIV_ROUND_CLOSEST_ULL(val, 25 * 1000) * 2; + /* Overflow check: val is now <= 51 bits */ + } + break; + case LTC2945_VIN_H: + case LTC2945_MAX_VIN_H: + case LTC2945_MIN_VIN_H: + case LTC2945_MAX_VIN_THRES_H: + case LTC2945_MIN_VIN_THRES_H: + /* 25 mV resolution. */ + val = DIV_ROUND_CLOSEST_ULL(val, 25); + break; + case LTC2945_ADIN_H: + case LTC2945_MAX_ADIN_H: + case LTC2945_MIN_ADIN_THRES_H: + case LTC2945_MAX_ADIN_THRES_H: + case LTC2945_MIN_ADIN_H: + /* 0.5mV resolution. */ + val *= 2; + break; + case LTC2945_SENSE_H: + case LTC2945_MAX_SENSE_H: + case LTC2945_MIN_SENSE_H: + case LTC2945_MAX_SENSE_THRES_H: + case LTC2945_MIN_SENSE_THRES_H: + /* 25 uV resolution. Convert to mA. */ + val *= shunt_resistor; + /* Overflow check: Assuming 32-bit val and 32-bit shunt resistor, val is 64bits */ + val = DIV_ROUND_CLOSEST_ULL(val, 25 * 1000); + /* Overflow check: val is now <= 50 bits */ + break; + default: + return -EINVAL; + } + return val; +} + +static ssize_t ltc2945_value_show(struct device *dev, + struct device_attribute *da, char *buf) +{ + struct sensor_device_attribute *attr = to_sensor_dev_attr(da); + long long value; + + value = ltc2945_reg_to_val(dev, attr->index); + if (value < 0) + return value; + return sysfs_emit(buf, "%lld\n", value); +} + +static ssize_t ltc2945_value_store(struct device *dev, + struct device_attribute *da, + const char *buf, size_t count) +{ + struct sensor_device_attribute *attr = to_sensor_dev_attr(da); + struct ltc2945_data *data = dev_get_drvdata(dev); + struct regmap *regmap = data->regmap; + u8 reg = attr->index; + unsigned int val; + u8 regbuf[3]; + int num_regs; + long long regval; + int ret; + + ret = kstrtouint(buf, 10, &val); + if (ret) + return ret; + + /* convert to register value, then clamp and write result */ + regval = ltc2945_val_to_reg(dev, reg, val); + if (regval < 0) + return regval; + if (is_power_reg(reg)) { + regval = clamp_val(regval, 0, 0xffffff); + regbuf[0] = regval >> 16; + regbuf[1] = (regval >> 8) & 0xff; + regbuf[2] = regval; + num_regs = 3; + } else { + regval = clamp_val(regval, 0, 0xfff) << 4; + regbuf[0] = regval >> 8; + regbuf[1] = regval & 0xff; + num_regs = 2; + } + ret = regmap_bulk_write(regmap, reg, regbuf, num_regs); + return ret < 0 ? ret : count; +} + +static ssize_t ltc2945_history_store(struct device *dev, + struct device_attribute *da, + const char *buf, size_t count) +{ + struct sensor_device_attribute *attr = to_sensor_dev_attr(da); + struct ltc2945_data *data = dev_get_drvdata(dev); + struct regmap *regmap = data->regmap; + u8 reg = attr->index; + int num_regs = is_power_reg(reg) ? 3 : 2; + u8 buf_min[3] = { 0xff, 0xff, 0xff }; + u8 buf_max[3] = { 0, 0, 0 }; + unsigned long val; + int ret; + + ret = kstrtoul(buf, 10, &val); + if (ret) + return ret; + if (val != 1) + return -EINVAL; + + ret = regmap_update_bits(regmap, LTC2945_CONTROL, CONTROL_TEST_MODE, + CONTROL_TEST_MODE); + + /* Reset minimum */ + ret = regmap_bulk_write(regmap, reg, buf_min, num_regs); + if (ret) + return ret; + + switch (reg) { + case LTC2945_MIN_POWER_H: + reg = LTC2945_MAX_POWER_H; + break; + case LTC2945_MIN_SENSE_H: + reg = LTC2945_MAX_SENSE_H; + break; + case LTC2945_MIN_VIN_H: + reg = LTC2945_MAX_VIN_H; + break; + case LTC2945_MIN_ADIN_H: + reg = LTC2945_MAX_ADIN_H; + break; + default: + WARN_ONCE(1, "Bad register: 0x%x\n", reg); + return -EINVAL; + } + /* Reset maximum */ + ret = regmap_bulk_write(regmap, reg, buf_max, num_regs); + + /* Try resetting test mode even if there was an error */ + regmap_update_bits(regmap, LTC2945_CONTROL, CONTROL_TEST_MODE, 0); + + return ret ? : count; +} + +static ssize_t ltc2945_bool_show(struct device *dev, + struct device_attribute *da, char *buf) +{ + struct sensor_device_attribute *attr = to_sensor_dev_attr(da); + struct ltc2945_data *data = dev_get_drvdata(dev); + struct regmap *regmap = data->regmap; + unsigned int fault; + int ret; + + ret = regmap_read(regmap, LTC2945_FAULT, &fault); + if (ret < 0) + return ret; + + fault &= attr->index; + if (fault) /* Clear reported faults in chip register */ + regmap_update_bits(regmap, LTC2945_FAULT, attr->index, 0); + + return sysfs_emit(buf, "%d\n", !!fault); +} + +/* Input voltages */ + +static SENSOR_DEVICE_ATTR_RO(in1_input, ltc2945_value, LTC2945_VIN_H); +static SENSOR_DEVICE_ATTR_RW(in1_min, ltc2945_value, LTC2945_MIN_VIN_THRES_H); +static SENSOR_DEVICE_ATTR_RW(in1_max, ltc2945_value, LTC2945_MAX_VIN_THRES_H); +static SENSOR_DEVICE_ATTR_RO(in1_lowest, ltc2945_value, LTC2945_MIN_VIN_H); +static SENSOR_DEVICE_ATTR_RO(in1_highest, ltc2945_value, LTC2945_MAX_VIN_H); +static SENSOR_DEVICE_ATTR_WO(in1_reset_history, ltc2945_history, + LTC2945_MIN_VIN_H); + +static SENSOR_DEVICE_ATTR_RO(in2_input, ltc2945_value, LTC2945_ADIN_H); +static SENSOR_DEVICE_ATTR_RW(in2_min, ltc2945_value, LTC2945_MIN_ADIN_THRES_H); +static SENSOR_DEVICE_ATTR_RW(in2_max, ltc2945_value, LTC2945_MAX_ADIN_THRES_H); +static SENSOR_DEVICE_ATTR_RO(in2_lowest, ltc2945_value, LTC2945_MIN_ADIN_H); +static SENSOR_DEVICE_ATTR_RO(in2_highest, ltc2945_value, LTC2945_MAX_ADIN_H); +static SENSOR_DEVICE_ATTR_WO(in2_reset_history, ltc2945_history, + LTC2945_MIN_ADIN_H); + +/* Voltage alarms */ + +static SENSOR_DEVICE_ATTR_RO(in1_min_alarm, ltc2945_bool, FAULT_VIN_UV); +static SENSOR_DEVICE_ATTR_RO(in1_max_alarm, ltc2945_bool, FAULT_VIN_OV); +static SENSOR_DEVICE_ATTR_RO(in2_min_alarm, ltc2945_bool, FAULT_ADIN_UV); +static SENSOR_DEVICE_ATTR_RO(in2_max_alarm, ltc2945_bool, FAULT_ADIN_OV); + +/* Currents (via sense resistor) */ + +static SENSOR_DEVICE_ATTR_RO(curr1_input, ltc2945_value, LTC2945_SENSE_H); +static SENSOR_DEVICE_ATTR_RW(curr1_min, ltc2945_value, + LTC2945_MIN_SENSE_THRES_H); +static SENSOR_DEVICE_ATTR_RW(curr1_max, ltc2945_value, + LTC2945_MAX_SENSE_THRES_H); +static SENSOR_DEVICE_ATTR_RO(curr1_lowest, ltc2945_value, LTC2945_MIN_SENSE_H); +static SENSOR_DEVICE_ATTR_RO(curr1_highest, ltc2945_value, + LTC2945_MAX_SENSE_H); +static SENSOR_DEVICE_ATTR_WO(curr1_reset_history, ltc2945_history, + LTC2945_MIN_SENSE_H); + +/* Current alarms */ + +static SENSOR_DEVICE_ATTR_RO(curr1_min_alarm, ltc2945_bool, FAULT_SENSE_UV); +static SENSOR_DEVICE_ATTR_RO(curr1_max_alarm, ltc2945_bool, FAULT_SENSE_OV); + +/* Power */ + +static SENSOR_DEVICE_ATTR_RO(power1_input, ltc2945_value, LTC2945_POWER_H); +static SENSOR_DEVICE_ATTR_RW(power1_min, ltc2945_value, + LTC2945_MIN_POWER_THRES_H); +static SENSOR_DEVICE_ATTR_RW(power1_max, ltc2945_value, + LTC2945_MAX_POWER_THRES_H); +static SENSOR_DEVICE_ATTR_RO(power1_input_lowest, ltc2945_value, + LTC2945_MIN_POWER_H); +static SENSOR_DEVICE_ATTR_RO(power1_input_highest, ltc2945_value, + LTC2945_MAX_POWER_H); +static SENSOR_DEVICE_ATTR_WO(power1_reset_history, ltc2945_history, + LTC2945_MIN_POWER_H); + +/* Power alarms */ + +static SENSOR_DEVICE_ATTR_RO(power1_min_alarm, ltc2945_bool, FAULT_POWER_UV); +static SENSOR_DEVICE_ATTR_RO(power1_max_alarm, ltc2945_bool, FAULT_POWER_OV); + +static struct attribute *ltc2945_attrs[] = { + &sensor_dev_attr_in1_input.dev_attr.attr, + &sensor_dev_attr_in1_min.dev_attr.attr, + &sensor_dev_attr_in1_max.dev_attr.attr, + &sensor_dev_attr_in1_lowest.dev_attr.attr, + &sensor_dev_attr_in1_highest.dev_attr.attr, + &sensor_dev_attr_in1_reset_history.dev_attr.attr, + &sensor_dev_attr_in1_min_alarm.dev_attr.attr, + &sensor_dev_attr_in1_max_alarm.dev_attr.attr, + + &sensor_dev_attr_in2_input.dev_attr.attr, + &sensor_dev_attr_in2_min.dev_attr.attr, + &sensor_dev_attr_in2_max.dev_attr.attr, + &sensor_dev_attr_in2_lowest.dev_attr.attr, + &sensor_dev_attr_in2_highest.dev_attr.attr, + &sensor_dev_attr_in2_reset_history.dev_attr.attr, + &sensor_dev_attr_in2_min_alarm.dev_attr.attr, + &sensor_dev_attr_in2_max_alarm.dev_attr.attr, + + &sensor_dev_attr_curr1_input.dev_attr.attr, + &sensor_dev_attr_curr1_min.dev_attr.attr, + &sensor_dev_attr_curr1_max.dev_attr.attr, + &sensor_dev_attr_curr1_lowest.dev_attr.attr, + &sensor_dev_attr_curr1_highest.dev_attr.attr, + &sensor_dev_attr_curr1_reset_history.dev_attr.attr, + &sensor_dev_attr_curr1_min_alarm.dev_attr.attr, + &sensor_dev_attr_curr1_max_alarm.dev_attr.attr, + + &sensor_dev_attr_power1_input.dev_attr.attr, + &sensor_dev_attr_power1_min.dev_attr.attr, + &sensor_dev_attr_power1_max.dev_attr.attr, + &sensor_dev_attr_power1_input_lowest.dev_attr.attr, + &sensor_dev_attr_power1_input_highest.dev_attr.attr, + &sensor_dev_attr_power1_reset_history.dev_attr.attr, + &sensor_dev_attr_power1_min_alarm.dev_attr.attr, + &sensor_dev_attr_power1_max_alarm.dev_attr.attr, + + NULL, +}; +ATTRIBUTE_GROUPS(ltc2945); + +static const struct regmap_config ltc2945_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = LTC2945_MIN_ADIN_THRES_L, +}; + +static int ltc2945_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + struct device *hwmon_dev; + struct regmap *regmap; + struct ltc2945_data *data; + + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + dev_set_drvdata(dev, data); + + regmap = devm_regmap_init_i2c(client, <c2945_regmap_config); + if (IS_ERR(regmap)) { + dev_err(dev, "failed to allocate register map\n"); + return PTR_ERR(regmap); + } + + data->regmap = regmap; + if (device_property_read_u32(dev, "shunt-resistor-micro-ohms", + &data->shunt_resistor)) + data->shunt_resistor = 1000; + + if (data->shunt_resistor == 0) + return -EINVAL; + + /* Clear faults */ + regmap_write(regmap, LTC2945_FAULT, 0x00); + + hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name, + data, + ltc2945_groups); + return PTR_ERR_OR_ZERO(hwmon_dev); +} + +static const struct i2c_device_id ltc2945_id[] = { + { .name = "ltc2945" }, + { } +}; + +MODULE_DEVICE_TABLE(i2c, ltc2945_id); + +static struct i2c_driver ltc2945_driver = { + .driver = { + .name = "ltc2945", + .of_match_table = of_match_ptr(ltc2945_of_match), + }, + .probe = ltc2945_probe, + .id_table = ltc2945_id, +}; + +module_i2c_driver(ltc2945_driver); + +MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>"); +MODULE_DESCRIPTION("LTC2945 driver"); +MODULE_LICENSE("GPL"); |
