linux/drivers/hwmon/emc2103.c
Vishwas M 14b0e83dc4 hwmon: (emc2103) fix unable to change fan pwm1_enable attribute
This patch fixes a bug which does not let FAN mode to be changed from
sysfs(pwm1_enable). i.e pwm1_enable can not be set to 3, it will always
remain at 0.

This is caused because the device driver handles the result of
"read_u8_from_i2c(client, REG_FAN_CONF1, &conf_reg)" incorrectly. The
driver thinks an error has occurred if the (result != 0). This has been
fixed by changing the condition to (result < 0).

Signed-off-by: Vishwas M <vishwas.reddy.vr@gmail.com>
Link: https://lore.kernel.org/r/20200707142747.118414-1-vishwas.reddy.vr@gmail.com
Fixes: 9df7305b5a ("hwmon: Add driver for SMSC EMC2103 temperature monitor and fan controller")
Cc: stable@vger.kernel.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2020-07-07 07:54:32 -07:00

667 lines
18 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* emc2103.c - Support for SMSC EMC2103
* Copyright (c) 2010 SMSC
*/
#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>
/* Addresses scanned */
static const unsigned short normal_i2c[] = { 0x2E, I2C_CLIENT_END };
static const u8 REG_TEMP[4] = { 0x00, 0x02, 0x04, 0x06 };
static const u8 REG_TEMP_MIN[4] = { 0x3c, 0x38, 0x39, 0x3a };
static const u8 REG_TEMP_MAX[4] = { 0x34, 0x30, 0x31, 0x32 };
#define REG_CONF1 0x20
#define REG_TEMP_MAX_ALARM 0x24
#define REG_TEMP_MIN_ALARM 0x25
#define REG_FAN_CONF1 0x42
#define REG_FAN_TARGET_LO 0x4c
#define REG_FAN_TARGET_HI 0x4d
#define REG_FAN_TACH_HI 0x4e
#define REG_FAN_TACH_LO 0x4f
#define REG_PRODUCT_ID 0xfd
#define REG_MFG_ID 0xfe
/* equation 4 from datasheet: rpm = (3932160 * multipler) / count */
#define FAN_RPM_FACTOR 3932160
/*
* 2103-2 and 2103-4's 3rd temperature sensor can be connected to two diodes
* in anti-parallel mode, and in this configuration both can be read
* independently (so we have 4 temperature inputs). The device can't
* detect if it's connected in this mode, so we have to manually enable
* it. Default is to leave the device in the state it's already in (-1).
* This parameter allows APD mode to be optionally forced on or off
*/
static int apd = -1;
module_param(apd, bint, 0);
MODULE_PARM_DESC(apd, "Set to zero to disable anti-parallel diode mode");
struct temperature {
s8 degrees;
u8 fraction; /* 0-7 multiples of 0.125 */
};
struct emc2103_data {
struct i2c_client *client;
const struct attribute_group *groups[4];
struct mutex update_lock;
bool valid; /* registers are valid */
bool fan_rpm_control;
int temp_count; /* num of temp sensors */
unsigned long last_updated; /* in jiffies */
struct temperature temp[4]; /* internal + 3 external */
s8 temp_min[4]; /* no fractional part */
s8 temp_max[4]; /* no fractional part */
u8 temp_min_alarm;
u8 temp_max_alarm;
u8 fan_multiplier;
u16 fan_tach;
u16 fan_target;
};
static int read_u8_from_i2c(struct i2c_client *client, u8 i2c_reg, u8 *output)
{
int status = i2c_smbus_read_byte_data(client, i2c_reg);
if (status < 0) {
dev_warn(&client->dev, "reg 0x%02x, err %d\n",
i2c_reg, status);
} else {
*output = status;
}
return status;
}
static void read_temp_from_i2c(struct i2c_client *client, u8 i2c_reg,
struct temperature *temp)
{
u8 degrees, fractional;
if (read_u8_from_i2c(client, i2c_reg, &degrees) < 0)
return;
if (read_u8_from_i2c(client, i2c_reg + 1, &fractional) < 0)
return;
temp->degrees = degrees;
temp->fraction = (fractional & 0xe0) >> 5;
}
static void read_fan_from_i2c(struct i2c_client *client, u16 *output,
u8 hi_addr, u8 lo_addr)
{
u8 high_byte, lo_byte;
if (read_u8_from_i2c(client, hi_addr, &high_byte) < 0)
return;
if (read_u8_from_i2c(client, lo_addr, &lo_byte) < 0)
return;
*output = ((u16)high_byte << 5) | (lo_byte >> 3);
}
static void write_fan_target_to_i2c(struct i2c_client *client, u16 new_target)
{
u8 high_byte = (new_target & 0x1fe0) >> 5;
u8 low_byte = (new_target & 0x001f) << 3;
i2c_smbus_write_byte_data(client, REG_FAN_TARGET_LO, low_byte);
i2c_smbus_write_byte_data(client, REG_FAN_TARGET_HI, high_byte);
}
static void read_fan_config_from_i2c(struct i2c_client *client)
{
struct emc2103_data *data = i2c_get_clientdata(client);
u8 conf1;
if (read_u8_from_i2c(client, REG_FAN_CONF1, &conf1) < 0)
return;
data->fan_multiplier = 1 << ((conf1 & 0x60) >> 5);
data->fan_rpm_control = (conf1 & 0x80) != 0;
}
static struct emc2103_data *emc2103_update_device(struct device *dev)
{
struct emc2103_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
mutex_lock(&data->update_lock);
if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
|| !data->valid) {
int i;
for (i = 0; i < data->temp_count; i++) {
read_temp_from_i2c(client, REG_TEMP[i], &data->temp[i]);
read_u8_from_i2c(client, REG_TEMP_MIN[i],
&data->temp_min[i]);
read_u8_from_i2c(client, REG_TEMP_MAX[i],
&data->temp_max[i]);
}
read_u8_from_i2c(client, REG_TEMP_MIN_ALARM,
&data->temp_min_alarm);
read_u8_from_i2c(client, REG_TEMP_MAX_ALARM,
&data->temp_max_alarm);
read_fan_from_i2c(client, &data->fan_tach,
REG_FAN_TACH_HI, REG_FAN_TACH_LO);
read_fan_from_i2c(client, &data->fan_target,
REG_FAN_TARGET_HI, REG_FAN_TARGET_LO);
read_fan_config_from_i2c(client);
data->last_updated = jiffies;
data->valid = true;
}
mutex_unlock(&data->update_lock);
return data;
}
static ssize_t
temp_show(struct device *dev, struct device_attribute *da, char *buf)
{
int nr = to_sensor_dev_attr(da)->index;
struct emc2103_data *data = emc2103_update_device(dev);
int millidegrees = data->temp[nr].degrees * 1000
+ data->temp[nr].fraction * 125;
return sprintf(buf, "%d\n", millidegrees);
}
static ssize_t
temp_min_show(struct device *dev, struct device_attribute *da, char *buf)
{
int nr = to_sensor_dev_attr(da)->index;
struct emc2103_data *data = emc2103_update_device(dev);
int millidegrees = data->temp_min[nr] * 1000;
return sprintf(buf, "%d\n", millidegrees);
}
static ssize_t
temp_max_show(struct device *dev, struct device_attribute *da, char *buf)
{
int nr = to_sensor_dev_attr(da)->index;
struct emc2103_data *data = emc2103_update_device(dev);
int millidegrees = data->temp_max[nr] * 1000;
return sprintf(buf, "%d\n", millidegrees);
}
static ssize_t
temp_fault_show(struct device *dev, struct device_attribute *da, char *buf)
{
int nr = to_sensor_dev_attr(da)->index;
struct emc2103_data *data = emc2103_update_device(dev);
bool fault = (data->temp[nr].degrees == -128);
return sprintf(buf, "%d\n", fault ? 1 : 0);
}
static ssize_t
temp_min_alarm_show(struct device *dev, struct device_attribute *da,
char *buf)
{
int nr = to_sensor_dev_attr(da)->index;
struct emc2103_data *data = emc2103_update_device(dev);
bool alarm = data->temp_min_alarm & (1 << nr);
return sprintf(buf, "%d\n", alarm ? 1 : 0);
}
static ssize_t
temp_max_alarm_show(struct device *dev, struct device_attribute *da,
char *buf)
{
int nr = to_sensor_dev_attr(da)->index;
struct emc2103_data *data = emc2103_update_device(dev);
bool alarm = data->temp_max_alarm & (1 << nr);
return sprintf(buf, "%d\n", alarm ? 1 : 0);
}
static ssize_t temp_min_store(struct device *dev, struct device_attribute *da,
const char *buf, size_t count)
{
int nr = to_sensor_dev_attr(da)->index;
struct emc2103_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
long val;
int result = kstrtol(buf, 10, &val);
if (result < 0)
return result;
val = DIV_ROUND_CLOSEST(clamp_val(val, -63000, 127000), 1000);
mutex_lock(&data->update_lock);
data->temp_min[nr] = val;
i2c_smbus_write_byte_data(client, REG_TEMP_MIN[nr], val);
mutex_unlock(&data->update_lock);
return count;
}
static ssize_t temp_max_store(struct device *dev, struct device_attribute *da,
const char *buf, size_t count)
{
int nr = to_sensor_dev_attr(da)->index;
struct emc2103_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
long val;
int result = kstrtol(buf, 10, &val);
if (result < 0)
return result;
val = DIV_ROUND_CLOSEST(clamp_val(val, -63000, 127000), 1000);
mutex_lock(&data->update_lock);
data->temp_max[nr] = val;
i2c_smbus_write_byte_data(client, REG_TEMP_MAX[nr], val);
mutex_unlock(&data->update_lock);
return count;
}
static ssize_t
fan1_input_show(struct device *dev, struct device_attribute *da, char *buf)
{
struct emc2103_data *data = emc2103_update_device(dev);
int rpm = 0;
if (data->fan_tach != 0)
rpm = (FAN_RPM_FACTOR * data->fan_multiplier) / data->fan_tach;
return sprintf(buf, "%d\n", rpm);
}
static ssize_t
fan1_div_show(struct device *dev, struct device_attribute *da, char *buf)
{
struct emc2103_data *data = emc2103_update_device(dev);
int fan_div = 8 / data->fan_multiplier;
return sprintf(buf, "%d\n", fan_div);
}
/*
* Note: we also update the fan target here, because its value is
* determined in part by the fan clock divider. This follows the principle
* of least surprise; the user doesn't expect the fan target to change just
* because the divider changed.
*/
static ssize_t fan1_div_store(struct device *dev, struct device_attribute *da,
const char *buf, size_t count)
{
struct emc2103_data *data = emc2103_update_device(dev);
struct i2c_client *client = data->client;
int new_range_bits, old_div = 8 / data->fan_multiplier;
long new_div;
int status = kstrtol(buf, 10, &new_div);
if (status < 0)
return status;
if (new_div == old_div) /* No change */
return count;
switch (new_div) {
case 1:
new_range_bits = 3;
break;
case 2:
new_range_bits = 2;
break;
case 4:
new_range_bits = 1;
break;
case 8:
new_range_bits = 0;
break;
default:
return -EINVAL;
}
mutex_lock(&data->update_lock);
status = i2c_smbus_read_byte_data(client, REG_FAN_CONF1);
if (status < 0) {
dev_dbg(&client->dev, "reg 0x%02x, err %d\n",
REG_FAN_CONF1, status);
mutex_unlock(&data->update_lock);
return status;
}
status &= 0x9F;
status |= (new_range_bits << 5);
i2c_smbus_write_byte_data(client, REG_FAN_CONF1, status);
data->fan_multiplier = 8 / new_div;
/* update fan target if high byte is not disabled */
if ((data->fan_target & 0x1fe0) != 0x1fe0) {
u16 new_target = (data->fan_target * old_div) / new_div;
data->fan_target = min(new_target, (u16)0x1fff);
write_fan_target_to_i2c(client, data->fan_target);
}
/* invalidate data to force re-read from hardware */
data->valid = false;
mutex_unlock(&data->update_lock);
return count;
}
static ssize_t
fan1_target_show(struct device *dev, struct device_attribute *da, char *buf)
{
struct emc2103_data *data = emc2103_update_device(dev);
int rpm = 0;
/* high byte of 0xff indicates disabled so return 0 */
if ((data->fan_target != 0) && ((data->fan_target & 0x1fe0) != 0x1fe0))
rpm = (FAN_RPM_FACTOR * data->fan_multiplier)
/ data->fan_target;
return sprintf(buf, "%d\n", rpm);
}
static ssize_t fan1_target_store(struct device *dev,
struct device_attribute *da, const char *buf,
size_t count)
{
struct emc2103_data *data = emc2103_update_device(dev);
struct i2c_client *client = data->client;
unsigned long rpm_target;
int result = kstrtoul(buf, 10, &rpm_target);
if (result < 0)
return result;
/* Datasheet states 16384 as maximum RPM target (table 3.2) */
rpm_target = clamp_val(rpm_target, 0, 16384);
mutex_lock(&data->update_lock);
if (rpm_target == 0)
data->fan_target = 0x1fff;
else
data->fan_target = clamp_val(
(FAN_RPM_FACTOR * data->fan_multiplier) / rpm_target,
0, 0x1fff);
write_fan_target_to_i2c(client, data->fan_target);
mutex_unlock(&data->update_lock);
return count;
}
static ssize_t
fan1_fault_show(struct device *dev, struct device_attribute *da, char *buf)
{
struct emc2103_data *data = emc2103_update_device(dev);
bool fault = ((data->fan_tach & 0x1fe0) == 0x1fe0);
return sprintf(buf, "%d\n", fault ? 1 : 0);
}
static ssize_t
pwm1_enable_show(struct device *dev, struct device_attribute *da, char *buf)
{
struct emc2103_data *data = emc2103_update_device(dev);
return sprintf(buf, "%d\n", data->fan_rpm_control ? 3 : 0);
}
static ssize_t pwm1_enable_store(struct device *dev,
struct device_attribute *da, const char *buf,
size_t count)
{
struct emc2103_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
long new_value;
u8 conf_reg;
int result = kstrtol(buf, 10, &new_value);
if (result < 0)
return result;
mutex_lock(&data->update_lock);
switch (new_value) {
case 0:
data->fan_rpm_control = false;
break;
case 3:
data->fan_rpm_control = true;
break;
default:
count = -EINVAL;
goto err;
}
result = read_u8_from_i2c(client, REG_FAN_CONF1, &conf_reg);
if (result < 0) {
count = result;
goto err;
}
if (data->fan_rpm_control)
conf_reg |= 0x80;
else
conf_reg &= ~0x80;
i2c_smbus_write_byte_data(client, REG_FAN_CONF1, conf_reg);
err:
mutex_unlock(&data->update_lock);
return count;
}
static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, 0);
static SENSOR_DEVICE_ATTR_RW(temp1_min, temp_min, 0);
static SENSOR_DEVICE_ATTR_RW(temp1_max, temp_max, 0);
static SENSOR_DEVICE_ATTR_RO(temp1_fault, temp_fault, 0);
static SENSOR_DEVICE_ATTR_RO(temp1_min_alarm, temp_min_alarm, 0);
static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, temp_max_alarm, 0);
static SENSOR_DEVICE_ATTR_RO(temp2_input, temp, 1);
static SENSOR_DEVICE_ATTR_RW(temp2_min, temp_min, 1);
static SENSOR_DEVICE_ATTR_RW(temp2_max, temp_max, 1);
static SENSOR_DEVICE_ATTR_RO(temp2_fault, temp_fault, 1);
static SENSOR_DEVICE_ATTR_RO(temp2_min_alarm, temp_min_alarm, 1);
static SENSOR_DEVICE_ATTR_RO(temp2_max_alarm, temp_max_alarm, 1);
static SENSOR_DEVICE_ATTR_RO(temp3_input, temp, 2);
static SENSOR_DEVICE_ATTR_RW(temp3_min, temp_min, 2);
static SENSOR_DEVICE_ATTR_RW(temp3_max, temp_max, 2);
static SENSOR_DEVICE_ATTR_RO(temp3_fault, temp_fault, 2);
static SENSOR_DEVICE_ATTR_RO(temp3_min_alarm, temp_min_alarm, 2);
static SENSOR_DEVICE_ATTR_RO(temp3_max_alarm, temp_max_alarm, 2);
static SENSOR_DEVICE_ATTR_RO(temp4_input, temp, 3);
static SENSOR_DEVICE_ATTR_RW(temp4_min, temp_min, 3);
static SENSOR_DEVICE_ATTR_RW(temp4_max, temp_max, 3);
static SENSOR_DEVICE_ATTR_RO(temp4_fault, temp_fault, 3);
static SENSOR_DEVICE_ATTR_RO(temp4_min_alarm, temp_min_alarm, 3);
static SENSOR_DEVICE_ATTR_RO(temp4_max_alarm, temp_max_alarm, 3);
static DEVICE_ATTR_RO(fan1_input);
static DEVICE_ATTR_RW(fan1_div);
static DEVICE_ATTR_RW(fan1_target);
static DEVICE_ATTR_RO(fan1_fault);
static DEVICE_ATTR_RW(pwm1_enable);
/* sensors present on all models */
static struct attribute *emc2103_attributes[] = {
&sensor_dev_attr_temp1_input.dev_attr.attr,
&sensor_dev_attr_temp1_min.dev_attr.attr,
&sensor_dev_attr_temp1_max.dev_attr.attr,
&sensor_dev_attr_temp1_fault.dev_attr.attr,
&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
&sensor_dev_attr_temp2_input.dev_attr.attr,
&sensor_dev_attr_temp2_min.dev_attr.attr,
&sensor_dev_attr_temp2_max.dev_attr.attr,
&sensor_dev_attr_temp2_fault.dev_attr.attr,
&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
&dev_attr_fan1_input.attr,
&dev_attr_fan1_div.attr,
&dev_attr_fan1_target.attr,
&dev_attr_fan1_fault.attr,
&dev_attr_pwm1_enable.attr,
NULL
};
/* extra temperature sensors only present on 2103-2 and 2103-4 */
static struct attribute *emc2103_attributes_temp3[] = {
&sensor_dev_attr_temp3_input.dev_attr.attr,
&sensor_dev_attr_temp3_min.dev_attr.attr,
&sensor_dev_attr_temp3_max.dev_attr.attr,
&sensor_dev_attr_temp3_fault.dev_attr.attr,
&sensor_dev_attr_temp3_min_alarm.dev_attr.attr,
&sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
NULL
};
/* extra temperature sensors only present on 2103-2 and 2103-4 in APD mode */
static struct attribute *emc2103_attributes_temp4[] = {
&sensor_dev_attr_temp4_input.dev_attr.attr,
&sensor_dev_attr_temp4_min.dev_attr.attr,
&sensor_dev_attr_temp4_max.dev_attr.attr,
&sensor_dev_attr_temp4_fault.dev_attr.attr,
&sensor_dev_attr_temp4_min_alarm.dev_attr.attr,
&sensor_dev_attr_temp4_max_alarm.dev_attr.attr,
NULL
};
static const struct attribute_group emc2103_group = {
.attrs = emc2103_attributes,
};
static const struct attribute_group emc2103_temp3_group = {
.attrs = emc2103_attributes_temp3,
};
static const struct attribute_group emc2103_temp4_group = {
.attrs = emc2103_attributes_temp4,
};
static int
emc2103_probe(struct i2c_client *client, const struct i2c_device_id *id)
{
struct emc2103_data *data;
struct device *hwmon_dev;
int status, idx = 0;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
return -EIO;
data = devm_kzalloc(&client->dev, sizeof(struct emc2103_data),
GFP_KERNEL);
if (!data)
return -ENOMEM;
i2c_set_clientdata(client, data);
data->client = client;
mutex_init(&data->update_lock);
/* 2103-2 and 2103-4 have 3 external diodes, 2103-1 has 1 */
status = i2c_smbus_read_byte_data(client, REG_PRODUCT_ID);
if (status == 0x24) {
/* 2103-1 only has 1 external diode */
data->temp_count = 2;
} else {
/* 2103-2 and 2103-4 have 3 or 4 external diodes */
status = i2c_smbus_read_byte_data(client, REG_CONF1);
if (status < 0) {
dev_dbg(&client->dev, "reg 0x%02x, err %d\n", REG_CONF1,
status);
return status;
}
/* detect current state of hardware */
data->temp_count = (status & 0x01) ? 4 : 3;
/* force APD state if module parameter is set */
if (apd == 0) {
/* force APD mode off */
data->temp_count = 3;
status &= ~(0x01);
i2c_smbus_write_byte_data(client, REG_CONF1, status);
} else if (apd == 1) {
/* force APD mode on */
data->temp_count = 4;
status |= 0x01;
i2c_smbus_write_byte_data(client, REG_CONF1, status);
}
}
/* sysfs hooks */
data->groups[idx++] = &emc2103_group;
if (data->temp_count >= 3)
data->groups[idx++] = &emc2103_temp3_group;
if (data->temp_count == 4)
data->groups[idx++] = &emc2103_temp4_group;
hwmon_dev = devm_hwmon_device_register_with_groups(&client->dev,
client->name, data,
data->groups);
if (IS_ERR(hwmon_dev))
return PTR_ERR(hwmon_dev);
dev_info(&client->dev, "%s: sensor '%s'\n",
dev_name(hwmon_dev), client->name);
return 0;
}
static const struct i2c_device_id emc2103_ids[] = {
{ "emc2103", 0, },
{ /* LIST END */ }
};
MODULE_DEVICE_TABLE(i2c, emc2103_ids);
/* Return 0 if detection is successful, -ENODEV otherwise */
static int
emc2103_detect(struct i2c_client *new_client, struct i2c_board_info *info)
{
struct i2c_adapter *adapter = new_client->adapter;
int manufacturer, product;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
return -ENODEV;
manufacturer = i2c_smbus_read_byte_data(new_client, REG_MFG_ID);
if (manufacturer != 0x5D)
return -ENODEV;
product = i2c_smbus_read_byte_data(new_client, REG_PRODUCT_ID);
if ((product != 0x24) && (product != 0x26))
return -ENODEV;
strlcpy(info->type, "emc2103", I2C_NAME_SIZE);
return 0;
}
static struct i2c_driver emc2103_driver = {
.class = I2C_CLASS_HWMON,
.driver = {
.name = "emc2103",
},
.probe = emc2103_probe,
.id_table = emc2103_ids,
.detect = emc2103_detect,
.address_list = normal_i2c,
};
module_i2c_driver(emc2103_driver);
MODULE_AUTHOR("Steve Glendinning <steve.glendinning@shawell.net>");
MODULE_DESCRIPTION("SMSC EMC2103 hwmon driver");
MODULE_LICENSE("GPL");