1
linux/drivers/hwmon/max6639.c
Guenter Roeck 21a93a9e31 hwmon: (max6639) Use multi-byte regmap operations
Use multi-byte regmap operations where possible to reduce code size
and the need for mutex protection.

No functional changes.

Reviewed-by: Tzung-Bi Shih <tzungbi@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2024-07-31 10:43:51 -07:00

781 lines
19 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* max6639.c - Support for Maxim MAX6639
*
* 2-Channel Temperature Monitor with Dual PWM Fan-Speed Controller
*
* Copyright (C) 2010, 2011 Roland Stigge <stigge@antcom.de>
*
* based on the initial MAX6639 support from semptian.net
* by He Changqing <hechangqing@semptian.com>
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/i2c.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/platform_data/max6639.h>
#include <linux/regmap.h>
#include <linux/util_macros.h>
/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x2c, 0x2e, 0x2f, I2C_CLIENT_END };
/* The MAX6639 registers, valid channel numbers: 0, 1 */
#define MAX6639_REG_TEMP(ch) (0x00 + (ch))
#define MAX6639_REG_STATUS 0x02
#define MAX6639_REG_OUTPUT_MASK 0x03
#define MAX6639_REG_GCONFIG 0x04
#define MAX6639_REG_TEMP_EXT(ch) (0x05 + (ch))
#define MAX6639_REG_ALERT_LIMIT(ch) (0x08 + (ch))
#define MAX6639_REG_OT_LIMIT(ch) (0x0A + (ch))
#define MAX6639_REG_THERM_LIMIT(ch) (0x0C + (ch))
#define MAX6639_REG_FAN_CONFIG1(ch) (0x10 + (ch) * 4)
#define MAX6639_REG_FAN_CONFIG2a(ch) (0x11 + (ch) * 4)
#define MAX6639_REG_FAN_CONFIG2b(ch) (0x12 + (ch) * 4)
#define MAX6639_REG_FAN_CONFIG3(ch) (0x13 + (ch) * 4)
#define MAX6639_REG_FAN_CNT(ch) (0x20 + (ch))
#define MAX6639_REG_TARGET_CNT(ch) (0x22 + (ch))
#define MAX6639_REG_FAN_PPR(ch) (0x24 + (ch))
#define MAX6639_REG_TARGTDUTY(ch) (0x26 + (ch))
#define MAX6639_REG_FAN_START_TEMP(ch) (0x28 + (ch))
#define MAX6639_REG_DEVID 0x3D
#define MAX6639_REG_MANUID 0x3E
#define MAX6639_REG_DEVREV 0x3F
/* Register bits */
#define MAX6639_GCONFIG_STANDBY 0x80
#define MAX6639_GCONFIG_POR 0x40
#define MAX6639_GCONFIG_DISABLE_TIMEOUT 0x20
#define MAX6639_GCONFIG_CH2_LOCAL 0x10
#define MAX6639_GCONFIG_PWM_FREQ_HI 0x08
#define MAX6639_FAN_CONFIG1_PWM 0x80
#define MAX6639_FAN_CONFIG3_FREQ_MASK 0x03
#define MAX6639_FAN_CONFIG3_THERM_FULL_SPEED 0x40
#define MAX6639_NUM_CHANNELS 2
static const int rpm_ranges[] = { 2000, 4000, 8000, 16000 };
/* Supported PWM frequency */
static const unsigned int freq_table[] = { 20, 33, 50, 100, 5000, 8333, 12500,
25000 };
#define FAN_FROM_REG(val, rpm_range) ((val) == 0 || (val) == 255 ? \
0 : (rpm_ranges[rpm_range] * 30) / (val))
#define TEMP_LIMIT_TO_REG(val) clamp_val((val) / 1000, 0, 255)
/*
* Client data (each client gets its own)
*/
struct max6639_data {
struct regmap *regmap;
struct mutex update_lock;
/* Register values initialized only once */
u8 ppr[MAX6639_NUM_CHANNELS]; /* Pulses per rotation 0..3 for 1..4 ppr */
u8 rpm_range[MAX6639_NUM_CHANNELS]; /* Index in above rpm_ranges table */
/* Optional regulator for FAN supply */
struct regulator *reg;
};
static int max6639_temp_read_input(struct device *dev, int channel, long *temp)
{
u32 regs[2] = { MAX6639_REG_TEMP_EXT(channel), MAX6639_REG_TEMP(channel) };
struct max6639_data *data = dev_get_drvdata(dev);
u8 regvals[2];
int res;
res = regmap_multi_reg_read(data->regmap, regs, regvals, 2);
if (res < 0)
return res;
*temp = ((regvals[0] >> 5) | (regvals[1] << 3)) * 125;
return 0;
}
static int max6639_temp_read_fault(struct device *dev, int channel, long *fault)
{
struct max6639_data *data = dev_get_drvdata(dev);
unsigned int val;
int res;
res = regmap_read(data->regmap, MAX6639_REG_TEMP_EXT(channel), &val);
if (res < 0)
return res;
*fault = val & 1;
return 0;
}
static int max6639_temp_read_max(struct device *dev, int channel, long *max)
{
struct max6639_data *data = dev_get_drvdata(dev);
unsigned int val;
int res;
res = regmap_read(data->regmap, MAX6639_REG_THERM_LIMIT(channel), &val);
if (res < 0)
return res;
*max = (long)val * 1000;
return 0;
}
static int max6639_temp_read_crit(struct device *dev, int channel, long *crit)
{
struct max6639_data *data = dev_get_drvdata(dev);
unsigned int val;
int res;
res = regmap_read(data->regmap, MAX6639_REG_ALERT_LIMIT(channel), &val);
if (res < 0)
return res;
*crit = (long)val * 1000;
return 0;
}
static int max6639_temp_read_emergency(struct device *dev, int channel, long *emerg)
{
struct max6639_data *data = dev_get_drvdata(dev);
unsigned int val;
int res;
res = regmap_read(data->regmap, MAX6639_REG_OT_LIMIT(channel), &val);
if (res < 0)
return res;
*emerg = (long)val * 1000;
return 0;
}
static int max6639_get_status(struct device *dev, unsigned int *status)
{
struct max6639_data *data = dev_get_drvdata(dev);
unsigned int val;
int res;
res = regmap_read(data->regmap, MAX6639_REG_STATUS, &val);
if (res < 0)
return res;
*status = val;
return 0;
}
static int max6639_temp_set_max(struct max6639_data *data, int channel, long val)
{
int res;
res = regmap_write(data->regmap, MAX6639_REG_THERM_LIMIT(channel),
TEMP_LIMIT_TO_REG(val));
return res;
}
static int max6639_temp_set_crit(struct max6639_data *data, int channel, long val)
{
int res;
res = regmap_write(data->regmap, MAX6639_REG_ALERT_LIMIT(channel), TEMP_LIMIT_TO_REG(val));
return res;
}
static int max6639_temp_set_emergency(struct max6639_data *data, int channel, long val)
{
int res;
res = regmap_write(data->regmap, MAX6639_REG_OT_LIMIT(channel), TEMP_LIMIT_TO_REG(val));
return res;
}
static int max6639_read_fan(struct device *dev, u32 attr, int channel,
long *fan_val)
{
struct max6639_data *data = dev_get_drvdata(dev);
unsigned int val;
int res;
switch (attr) {
case hwmon_fan_input:
res = regmap_read(data->regmap, MAX6639_REG_FAN_CNT(channel), &val);
if (res < 0)
return res;
*fan_val = FAN_FROM_REG(val, data->rpm_range[channel]);
return 0;
case hwmon_fan_fault:
res = max6639_get_status(dev, &val);
if (res < 0)
return res;
*fan_val = !!(val & BIT(1 - channel));
return 0;
case hwmon_fan_pulses:
*fan_val = data->ppr[channel];
return 0;
default:
return -EOPNOTSUPP;
}
}
static int max6639_set_ppr(struct max6639_data *data, int channel, u8 ppr)
{
/* Decrement the PPR value and shift left by 6 to match the register format */
return regmap_write(data->regmap, MAX6639_REG_FAN_PPR(channel), ppr-- << 6);
}
static int max6639_write_fan(struct device *dev, u32 attr, int channel,
long val)
{
struct max6639_data *data = dev_get_drvdata(dev);
int err;
switch (attr) {
case hwmon_fan_pulses:
if (val <= 0 || val > 4)
return -EINVAL;
mutex_lock(&data->update_lock);
/* Set Fan pulse per revolution */
err = max6639_set_ppr(data, channel, val);
if (err < 0) {
mutex_unlock(&data->update_lock);
return err;
}
data->ppr[channel] = val;
mutex_unlock(&data->update_lock);
return 0;
default:
return -EOPNOTSUPP;
}
}
static umode_t max6639_fan_is_visible(const void *_data, u32 attr, int channel)
{
switch (attr) {
case hwmon_fan_input:
case hwmon_fan_fault:
return 0444;
case hwmon_fan_pulses:
return 0644;
default:
return 0;
}
}
static int max6639_read_pwm(struct device *dev, u32 attr, int channel,
long *pwm_val)
{
u32 regs[2] = { MAX6639_REG_FAN_CONFIG3(channel), MAX6639_REG_GCONFIG };
struct max6639_data *data = dev_get_drvdata(dev);
unsigned int val;
u8 regvals[2];
int res;
u8 i;
switch (attr) {
case hwmon_pwm_input:
res = regmap_read(data->regmap, MAX6639_REG_TARGTDUTY(channel), &val);
if (res < 0)
return res;
*pwm_val = val * 255 / 120;
return 0;
case hwmon_pwm_freq:
res = regmap_multi_reg_read(data->regmap, regs, regvals, 2);
if (res < 0)
return res;
i = regvals[0] & MAX6639_FAN_CONFIG3_FREQ_MASK;
if (regvals[1] & MAX6639_GCONFIG_PWM_FREQ_HI)
i |= 0x4;
*pwm_val = freq_table[i];
return 0;
default:
return -EOPNOTSUPP;
}
}
static int max6639_write_pwm(struct device *dev, u32 attr, int channel,
long val)
{
struct max6639_data *data = dev_get_drvdata(dev);
int err;
u8 i;
switch (attr) {
case hwmon_pwm_input:
if (val < 0 || val > 255)
return -EINVAL;
err = regmap_write(data->regmap, MAX6639_REG_TARGTDUTY(channel),
val * 120 / 255);
return err;
case hwmon_pwm_freq:
val = clamp_val(val, 0, 25000);
i = find_closest(val, freq_table, ARRAY_SIZE(freq_table));
mutex_lock(&data->update_lock);
err = regmap_update_bits(data->regmap, MAX6639_REG_FAN_CONFIG3(channel),
MAX6639_FAN_CONFIG3_FREQ_MASK, i);
if (err < 0) {
mutex_unlock(&data->update_lock);
return err;
}
if (i >> 2)
err = regmap_set_bits(data->regmap, MAX6639_REG_GCONFIG,
MAX6639_GCONFIG_PWM_FREQ_HI);
else
err = regmap_clear_bits(data->regmap, MAX6639_REG_GCONFIG,
MAX6639_GCONFIG_PWM_FREQ_HI);
mutex_unlock(&data->update_lock);
return err;
default:
return -EOPNOTSUPP;
}
}
static umode_t max6639_pwm_is_visible(const void *_data, u32 attr, int channel)
{
switch (attr) {
case hwmon_pwm_input:
case hwmon_pwm_freq:
return 0644;
default:
return 0;
}
}
static int max6639_read_temp(struct device *dev, u32 attr, int channel,
long *val)
{
unsigned int status;
int res;
switch (attr) {
case hwmon_temp_input:
res = max6639_temp_read_input(dev, channel, val);
return res;
case hwmon_temp_fault:
res = max6639_temp_read_fault(dev, channel, val);
return res;
case hwmon_temp_max:
res = max6639_temp_read_max(dev, channel, val);
return res;
case hwmon_temp_crit:
res = max6639_temp_read_crit(dev, channel, val);
return res;
case hwmon_temp_emergency:
res = max6639_temp_read_emergency(dev, channel, val);
return res;
case hwmon_temp_max_alarm:
res = max6639_get_status(dev, &status);
if (res < 0)
return res;
*val = !!(status & BIT(3 - channel));
return 0;
case hwmon_temp_crit_alarm:
res = max6639_get_status(dev, &status);
if (res < 0)
return res;
*val = !!(status & BIT(7 - channel));
return 0;
case hwmon_temp_emergency_alarm:
res = max6639_get_status(dev, &status);
if (res < 0)
return res;
*val = !!(status & BIT(5 - channel));
return 0;
default:
return -EOPNOTSUPP;
}
}
static int max6639_write_temp(struct device *dev, u32 attr, int channel,
long val)
{
struct max6639_data *data = dev_get_drvdata(dev);
switch (attr) {
case hwmon_temp_max:
return max6639_temp_set_max(data, channel, val);
case hwmon_temp_crit:
return max6639_temp_set_crit(data, channel, val);
case hwmon_temp_emergency:
return max6639_temp_set_emergency(data, channel, val);
default:
return -EOPNOTSUPP;
}
}
static umode_t max6639_temp_is_visible(const void *_data, u32 attr, int channel)
{
switch (attr) {
case hwmon_temp_input:
case hwmon_temp_fault:
case hwmon_temp_max_alarm:
case hwmon_temp_crit_alarm:
case hwmon_temp_emergency_alarm:
return 0444;
case hwmon_temp_max:
case hwmon_temp_crit:
case hwmon_temp_emergency:
return 0644;
default:
return 0;
}
}
static int max6639_read(struct device *dev, enum hwmon_sensor_types type,
u32 attr, int channel, long *val)
{
switch (type) {
case hwmon_fan:
return max6639_read_fan(dev, attr, channel, val);
case hwmon_pwm:
return max6639_read_pwm(dev, attr, channel, val);
case hwmon_temp:
return max6639_read_temp(dev, attr, channel, val);
default:
return -EOPNOTSUPP;
}
}
static int max6639_write(struct device *dev, enum hwmon_sensor_types type,
u32 attr, int channel, long val)
{
switch (type) {
case hwmon_fan:
return max6639_write_fan(dev, attr, channel, val);
case hwmon_pwm:
return max6639_write_pwm(dev, attr, channel, val);
case hwmon_temp:
return max6639_write_temp(dev, attr, channel, val);
default:
return -EOPNOTSUPP;
}
}
static umode_t max6639_is_visible(const void *data,
enum hwmon_sensor_types type,
u32 attr, int channel)
{
switch (type) {
case hwmon_fan:
return max6639_fan_is_visible(data, attr, channel);
case hwmon_pwm:
return max6639_pwm_is_visible(data, attr, channel);
case hwmon_temp:
return max6639_temp_is_visible(data, attr, channel);
default:
return 0;
}
}
static const struct hwmon_channel_info * const max6639_info[] = {
HWMON_CHANNEL_INFO(fan,
HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_PULSES,
HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_PULSES),
HWMON_CHANNEL_INFO(pwm,
HWMON_PWM_INPUT | HWMON_PWM_FREQ,
HWMON_PWM_INPUT | HWMON_PWM_FREQ),
HWMON_CHANNEL_INFO(temp,
HWMON_T_INPUT | HWMON_T_FAULT | HWMON_T_MAX | HWMON_T_MAX_ALARM |
HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_EMERGENCY |
HWMON_T_EMERGENCY_ALARM,
HWMON_T_INPUT | HWMON_T_FAULT | HWMON_T_MAX | HWMON_T_MAX_ALARM |
HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_EMERGENCY |
HWMON_T_EMERGENCY_ALARM),
NULL
};
static const struct hwmon_ops max6639_hwmon_ops = {
.is_visible = max6639_is_visible,
.read = max6639_read,
.write = max6639_write,
};
static const struct hwmon_chip_info max6639_chip_info = {
.ops = &max6639_hwmon_ops,
.info = max6639_info,
};
/*
* returns respective index in rpm_ranges table
* 1 by default on invalid range
*/
static int rpm_range_to_reg(int range)
{
int i;
for (i = 0; i < ARRAY_SIZE(rpm_ranges); i++) {
if (rpm_ranges[i] == range)
return i;
}
return 1; /* default: 4000 RPM */
}
static int max6639_init_client(struct i2c_client *client,
struct max6639_data *data)
{
struct max6639_platform_data *max6639_info =
dev_get_platdata(&client->dev);
int i;
int rpm_range = 1; /* default: 4000 RPM */
int err, ppr;
/* Reset chip to default values, see below for GCONFIG setup */
err = regmap_write(data->regmap, MAX6639_REG_GCONFIG, MAX6639_GCONFIG_POR);
if (err)
return err;
/* Fans pulse per revolution is 2 by default */
if (max6639_info && max6639_info->ppr > 0 &&
max6639_info->ppr < 5)
ppr = max6639_info->ppr;
else
ppr = 2;
data->ppr[0] = ppr;
data->ppr[1] = ppr;
if (max6639_info)
rpm_range = rpm_range_to_reg(max6639_info->rpm_range);
data->rpm_range[0] = rpm_range;
data->rpm_range[1] = rpm_range;
for (i = 0; i < MAX6639_NUM_CHANNELS; i++) {
/* Set Fan pulse per revolution */
err = max6639_set_ppr(data, i, data->ppr[i]);
if (err)
return err;
/* Fans config PWM, RPM */
err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG1(i),
MAX6639_FAN_CONFIG1_PWM | data->rpm_range[i]);
if (err)
return err;
/* Fans PWM polarity high by default */
if (max6639_info) {
if (max6639_info->pwm_polarity == 0)
err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG2a(i), 0x00);
else
err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG2a(i), 0x02);
}
if (err)
return err;
/*
* /THERM full speed enable,
* PWM frequency 25kHz, see also GCONFIG below
*/
err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG3(i),
MAX6639_FAN_CONFIG3_THERM_FULL_SPEED | 0x03);
if (err)
return err;
/* Max. temp. 80C/90C/100C */
err = regmap_write(data->regmap, MAX6639_REG_THERM_LIMIT(i), 80);
if (err)
return err;
err = regmap_write(data->regmap, MAX6639_REG_ALERT_LIMIT(i), 90);
if (err)
return err;
err = regmap_write(data->regmap, MAX6639_REG_OT_LIMIT(i), 100);
if (err)
return err;
/* PWM 120/120 (i.e. 100%) */
err = regmap_write(data->regmap, MAX6639_REG_TARGTDUTY(i), 120);
if (err)
return err;
}
/* Start monitoring */
return regmap_write(data->regmap, MAX6639_REG_GCONFIG,
MAX6639_GCONFIG_DISABLE_TIMEOUT | MAX6639_GCONFIG_CH2_LOCAL |
MAX6639_GCONFIG_PWM_FREQ_HI);
}
/* Return 0 if detection is successful, -ENODEV otherwise */
static int max6639_detect(struct i2c_client *client,
struct i2c_board_info *info)
{
struct i2c_adapter *adapter = client->adapter;
int dev_id, manu_id;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
return -ENODEV;
/* Actual detection via device and manufacturer ID */
dev_id = i2c_smbus_read_byte_data(client, MAX6639_REG_DEVID);
manu_id = i2c_smbus_read_byte_data(client, MAX6639_REG_MANUID);
if (dev_id != 0x58 || manu_id != 0x4D)
return -ENODEV;
strscpy(info->type, "max6639", I2C_NAME_SIZE);
return 0;
}
static void max6639_regulator_disable(void *data)
{
regulator_disable(data);
}
static bool max6639_regmap_is_volatile(struct device *dev, unsigned int reg)
{
switch (reg) {
case MAX6639_REG_TEMP(0):
case MAX6639_REG_TEMP_EXT(0):
case MAX6639_REG_TEMP(1):
case MAX6639_REG_TEMP_EXT(1):
case MAX6639_REG_STATUS:
case MAX6639_REG_FAN_CNT(0):
case MAX6639_REG_FAN_CNT(1):
case MAX6639_REG_TARGTDUTY(0):
case MAX6639_REG_TARGTDUTY(1):
return true;
default:
return false;
}
}
static const struct regmap_config max6639_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
.max_register = MAX6639_REG_DEVREV,
.cache_type = REGCACHE_MAPLE,
.volatile_reg = max6639_regmap_is_volatile,
};
static int max6639_probe(struct i2c_client *client)
{
struct device *dev = &client->dev;
struct max6639_data *data;
struct device *hwmon_dev;
int err;
data = devm_kzalloc(dev, sizeof(struct max6639_data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->regmap = devm_regmap_init_i2c(client, &max6639_regmap_config);
if (IS_ERR(data->regmap))
return dev_err_probe(dev,
PTR_ERR(data->regmap),
"regmap initialization failed\n");
data->reg = devm_regulator_get_optional(dev, "fan");
if (IS_ERR(data->reg)) {
if (PTR_ERR(data->reg) != -ENODEV)
return PTR_ERR(data->reg);
data->reg = NULL;
} else {
/* Spin up fans */
err = regulator_enable(data->reg);
if (err) {
dev_err(dev, "Failed to enable fan supply: %d\n", err);
return err;
}
err = devm_add_action_or_reset(dev, max6639_regulator_disable,
data->reg);
if (err) {
dev_err(dev, "Failed to register action: %d\n", err);
return err;
}
}
mutex_init(&data->update_lock);
/* Initialize the max6639 chip */
err = max6639_init_client(client, data);
if (err < 0)
return err;
hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
data, &max6639_chip_info,
NULL);
return PTR_ERR_OR_ZERO(hwmon_dev);
}
static int max6639_suspend(struct device *dev)
{
struct max6639_data *data = dev_get_drvdata(dev);
if (data->reg)
regulator_disable(data->reg);
return regmap_write_bits(data->regmap, MAX6639_REG_GCONFIG, MAX6639_GCONFIG_STANDBY,
MAX6639_GCONFIG_STANDBY);
}
static int max6639_resume(struct device *dev)
{
struct max6639_data *data = dev_get_drvdata(dev);
int ret;
if (data->reg) {
ret = regulator_enable(data->reg);
if (ret) {
dev_err(dev, "Failed to enable fan supply: %d\n", ret);
return ret;
}
}
return regmap_write_bits(data->regmap, MAX6639_REG_GCONFIG, MAX6639_GCONFIG_STANDBY,
~MAX6639_GCONFIG_STANDBY);
}
static const struct i2c_device_id max6639_id[] = {
{"max6639"},
{ }
};
MODULE_DEVICE_TABLE(i2c, max6639_id);
static DEFINE_SIMPLE_DEV_PM_OPS(max6639_pm_ops, max6639_suspend, max6639_resume);
static const struct of_device_id max6639_of_match[] = {
{ .compatible = "maxim,max6639", },
{ },
};
static struct i2c_driver max6639_driver = {
.class = I2C_CLASS_HWMON,
.driver = {
.name = "max6639",
.pm = pm_sleep_ptr(&max6639_pm_ops),
.of_match_table = max6639_of_match,
},
.probe = max6639_probe,
.id_table = max6639_id,
.detect = max6639_detect,
.address_list = normal_i2c,
};
module_i2c_driver(max6639_driver);
MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
MODULE_DESCRIPTION("max6639 driver");
MODULE_LICENSE("GPL");