linux-stable/drivers/hwmon/w83l785ts.c
Stephen Kitt 6748703856 hwmon: use simple i2c probe function
Many hwmon drivers don't use the id information provided by the old
i2c probe function, and the remainder can easily be adapted to the new
form ("probe_new") by calling i2c_match_id explicitly.

This avoids scanning the identifier tables during probes.

Drivers which didn't use the id are converted as-is; drivers which did
are modified as follows:

* if the information in i2c_client is sufficient, that's used instead
  (client->name);
* anything else is handled by calling i2c_match_id() with the same
  level of error-handling (if any) as before.

A few drivers aren't included in this patch because they have a
different set of maintainers. They will be covered by other patches.

Signed-off-by: Stephen Kitt <steve@sk2.org>
Link: https://lore.kernel.org/r/20200813160222.1503401-1-steve@sk2.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2020-09-23 09:42:39 -07:00

285 lines
7.2 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* w83l785ts.c - Part of lm_sensors, Linux kernel modules for hardware
* monitoring
* Copyright (C) 2003-2009 Jean Delvare <jdelvare@suse.de>
*
* Inspired from the lm83 driver. The W83L785TS-S is a sensor chip made
* by Winbond. It reports a single external temperature with a 1 deg
* resolution and a 3 deg accuracy. Datasheet can be obtained from
* Winbond's website at:
* http://www.winbond-usa.com/products/winbond_products/pdfs/PCIC/W83L785TS-S.pdf
*
* Ported to Linux 2.6 by Wolfgang Ziegler <nuppla@gmx.at> and Jean Delvare
* <jdelvare@suse.de>.
*
* Thanks to James Bolt <james@evilpenguin.com> for benchmarking the read
* error handling mechanism.
*/
#include <linux/module.h>
#include <linux/delay.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>
/* How many retries on register read error */
#define MAX_RETRIES 5
/*
* Address to scan
* Address is fully defined internally and cannot be changed.
*/
static const unsigned short normal_i2c[] = { 0x2e, I2C_CLIENT_END };
/*
* The W83L785TS-S registers
* Manufacturer ID is 0x5CA3 for Winbond.
*/
#define W83L785TS_REG_MAN_ID1 0x4D
#define W83L785TS_REG_MAN_ID2 0x4C
#define W83L785TS_REG_CHIP_ID 0x4E
#define W83L785TS_REG_CONFIG 0x40
#define W83L785TS_REG_TYPE 0x52
#define W83L785TS_REG_TEMP 0x27
#define W83L785TS_REG_TEMP_OVER 0x53 /* not sure about this one */
/*
* Conversions
* The W83L785TS-S uses signed 8-bit values.
*/
#define TEMP_FROM_REG(val) ((val) * 1000)
/*
* Functions declaration
*/
static int w83l785ts_probe(struct i2c_client *client);
static int w83l785ts_detect(struct i2c_client *client,
struct i2c_board_info *info);
static int w83l785ts_remove(struct i2c_client *client);
static u8 w83l785ts_read_value(struct i2c_client *client, u8 reg, u8 defval);
static struct w83l785ts_data *w83l785ts_update_device(struct device *dev);
/*
* Driver data (common to all clients)
*/
static const struct i2c_device_id w83l785ts_id[] = {
{ "w83l785ts", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, w83l785ts_id);
static struct i2c_driver w83l785ts_driver = {
.class = I2C_CLASS_HWMON,
.driver = {
.name = "w83l785ts",
},
.probe_new = w83l785ts_probe,
.remove = w83l785ts_remove,
.id_table = w83l785ts_id,
.detect = w83l785ts_detect,
.address_list = normal_i2c,
};
/*
* Client data (each client gets its own)
*/
struct w83l785ts_data {
struct device *hwmon_dev;
struct mutex update_lock;
char valid; /* zero until following fields are valid */
unsigned long last_updated; /* in jiffies */
/* registers values */
s8 temp[2]; /* 0: input, 1: critical limit */
};
/*
* Sysfs stuff
*/
static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct w83l785ts_data *data = w83l785ts_update_device(dev);
return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index]));
}
static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, show_temp, NULL, 1);
/*
* Real code
*/
/* Return 0 if detection is successful, -ENODEV otherwise */
static int w83l785ts_detect(struct i2c_client *client,
struct i2c_board_info *info)
{
struct i2c_adapter *adapter = client->adapter;
u16 man_id;
u8 chip_id;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
return -ENODEV;
/* detection */
if ((w83l785ts_read_value(client, W83L785TS_REG_CONFIG, 0) & 0x80)
|| (w83l785ts_read_value(client, W83L785TS_REG_TYPE, 0) & 0xFC)) {
dev_dbg(&adapter->dev,
"W83L785TS-S detection failed at 0x%02x\n",
client->addr);
return -ENODEV;
}
/* Identification */
man_id = (w83l785ts_read_value(client, W83L785TS_REG_MAN_ID1, 0) << 8)
+ w83l785ts_read_value(client, W83L785TS_REG_MAN_ID2, 0);
chip_id = w83l785ts_read_value(client, W83L785TS_REG_CHIP_ID, 0);
if (man_id != 0x5CA3 /* Winbond */
|| chip_id != 0x70) { /* W83L785TS-S */
dev_dbg(&adapter->dev,
"Unsupported chip (man_id=0x%04X, chip_id=0x%02X)\n",
man_id, chip_id);
return -ENODEV;
}
strlcpy(info->type, "w83l785ts", I2C_NAME_SIZE);
return 0;
}
static int w83l785ts_probe(struct i2c_client *client)
{
struct w83l785ts_data *data;
struct device *dev = &client->dev;
int err;
data = devm_kzalloc(dev, sizeof(struct w83l785ts_data), GFP_KERNEL);
if (!data)
return -ENOMEM;
i2c_set_clientdata(client, data);
mutex_init(&data->update_lock);
/*
* Initialize the W83L785TS chip
* Nothing yet, assume it is already started.
*/
err = device_create_file(dev, &sensor_dev_attr_temp1_input.dev_attr);
if (err)
return err;
err = device_create_file(dev, &sensor_dev_attr_temp1_max.dev_attr);
if (err)
goto exit_remove;
/* Register sysfs hooks */
data->hwmon_dev = hwmon_device_register(dev);
if (IS_ERR(data->hwmon_dev)) {
err = PTR_ERR(data->hwmon_dev);
goto exit_remove;
}
return 0;
exit_remove:
device_remove_file(dev, &sensor_dev_attr_temp1_input.dev_attr);
device_remove_file(dev, &sensor_dev_attr_temp1_max.dev_attr);
return err;
}
static int w83l785ts_remove(struct i2c_client *client)
{
struct w83l785ts_data *data = i2c_get_clientdata(client);
hwmon_device_unregister(data->hwmon_dev);
device_remove_file(&client->dev,
&sensor_dev_attr_temp1_input.dev_attr);
device_remove_file(&client->dev,
&sensor_dev_attr_temp1_max.dev_attr);
return 0;
}
static u8 w83l785ts_read_value(struct i2c_client *client, u8 reg, u8 defval)
{
int value, i;
struct device *dev;
const char *prefix;
/*
* We might be called during detection, at which point the client
* isn't yet fully initialized, so we can't use dev_dbg on it
*/
if (i2c_get_clientdata(client)) {
dev = &client->dev;
prefix = "";
} else {
dev = &client->adapter->dev;
prefix = "w83l785ts: ";
}
/*
* Frequent read errors have been reported on Asus boards, so we
* retry on read errors. If it still fails (unlikely), return the
* default value requested by the caller.
*/
for (i = 1; i <= MAX_RETRIES; i++) {
value = i2c_smbus_read_byte_data(client, reg);
if (value >= 0) {
dev_dbg(dev, "%sRead 0x%02x from register 0x%02x.\n",
prefix, value, reg);
return value;
}
dev_dbg(dev, "%sRead failed, will retry in %d.\n", prefix, i);
msleep(i);
}
dev_err(dev, "%sCouldn't read value from register 0x%02x.\n", prefix,
reg);
return defval;
}
static struct w83l785ts_data *w83l785ts_update_device(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct w83l785ts_data *data = i2c_get_clientdata(client);
mutex_lock(&data->update_lock);
if (!data->valid || time_after(jiffies, data->last_updated + HZ * 2)) {
dev_dbg(&client->dev, "Updating w83l785ts data.\n");
data->temp[0] = w83l785ts_read_value(client,
W83L785TS_REG_TEMP, data->temp[0]);
data->temp[1] = w83l785ts_read_value(client,
W83L785TS_REG_TEMP_OVER, data->temp[1]);
data->last_updated = jiffies;
data->valid = 1;
}
mutex_unlock(&data->update_lock);
return data;
}
module_i2c_driver(w83l785ts_driver);
MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>");
MODULE_DESCRIPTION("W83L785TS-S driver");
MODULE_LICENSE("GPL");