/*
* g762 - Driver for the Global Mixed-mode Technology Inc. fan speed
* PWM controller chips from G762 family, i.e. G762 and G763
*
* Copyright (C) 2013, Arnaud EBALARD <arno@natisbad.org>
*
* This work is based on a basic version for 2.6.31 kernel developed
* by Olivier Mouchet for LaCie. Updates and correction have been
* performed to run on recent kernels. Additional features, like the
* ability to configure various characteristics via .dts file or
* board init file have been added. Detailed datasheet on which this
* development is based is available here:
*
* http://natisbad.org/NAS/refs/GMT_EDS-762_763-080710-0.2.pdf
*
* Headers from previous developments have been kept below:
*
* Copyright (c) 2009 LaCie
*
* Author: Olivier Mouchet <olivier.mouchet@gmail.com>
*
* based on g760a code written by Herbert Valerio Riedel <hvr@gnu.org>
* Copyright (C) 2007 Herbert Valerio Riedel <hvr@gnu.org>
*
* g762: minimal datasheet available at:
* http://www.gmt.com.tw/product/datasheet/EDS-762_3.pdf
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation.
*/
#include <linux/device.h>
#include <linux/module.h>
#include <linux/init.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/kernel.h>
#include <linux/clk.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_data/g762.h>
#define DRVNAME "g762"
static const struct i2c_device_id g762_id[] = {
{ "g762", 0 },
{ "g763", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, g762_id);
enum g762_regs {
G762_REG_SET_CNT = 0x00,
G762_REG_ACT_CNT = 0x01,
G762_REG_FAN_STA = 0x02,
G762_REG_SET_OUT = 0x03,
G762_REG_FAN_CMD1 = 0x04,
G762_REG_FAN_CMD2 = 0x05,
};
/* Config register bits */
#define G762_REG_FAN_CMD1_DET_FAN_FAIL 0x80 /* enable fan_fail signal */
#define G762_REG_FAN_CMD1_DET_FAN_OOC 0x40 /* enable fan_out_of_control */
#define G762_REG_FAN_CMD1_OUT_MODE 0x20 /* out mode: PWM or DC */
#define G762_REG_FAN_CMD1_FAN_MODE 0x10 /* fan mode: closed/open-loop */
#define G762_REG_FAN_CMD1_CLK_DIV_ID1 0x08 /* clock divisor value */
#define G762_REG_FAN_CMD1_CLK_DIV_ID0 0x04
#define G762_REG_FAN_CMD1_PWM_POLARITY 0x02 /* PWM polarity */
#define G762_REG_FAN_CMD1_PULSE_PER_REV 0x01 /* pulse per fan revolution */
#define G762_REG_FAN_CMD2_GEAR_MODE_1 0x08 /* fan gear mode */
#define G762_REG_FAN_CMD2_GEAR_MODE_0 0x04
#define G762_REG_FAN_CMD2_FAN_STARTV_1 0x02 /* fan startup voltage */
#define G762_REG_FAN_CMD2_FAN_STARTV_0 0x01
#define G762_REG_FAN_STA_FAIL 0x02 /* fan fail */
#define G762_REG_FAN_STA_OOC 0x01 /* fan out of control */
/* Config register values */
#define G762_OUT_MODE_PWM 1
#define G762_OUT_MODE_DC 0
#define G762_FAN_MODE_CLOSED_LOOP 2
#define G762_FAN_MODE_OPEN_LOOP 1
#define G762_PWM_POLARITY_NEGATIVE 1
#define G762_PWM_POLARITY_POSITIVE 0
/* Register data is read (and cached) at most once per second. */
#define G762_UPDATE_INTERVAL HZ
/*
* Extract pulse count per fan revolution value (2 or 4) from given
* FAN_CMD1 register value.
*/
#define G762_PULSE_FROM_REG(reg) \
((((reg) & G762_REG_FAN_CMD1_PULSE_PER_REV) + 1) << 1)
/*
* Extract fan clock divisor (1, 2, 4 or 8) from given FAN_CMD1
* register value.
*/
#define G762_CLKDIV_FROM_REG(reg) \
(1 << (((reg) & (G762_REG_FAN_CMD1_CLK_DIV_ID0 | \
G762_REG_FAN_CMD1_CLK_DIV_ID1)) >> 2))
/*
* Extract fan gear mode multiplier value (0, 2 or 4) from given
* FAN_CMD2 register value.
*/
#define G762_GEARMULT_FROM_REG(reg) \
(1 << (((reg) & (G762_REG_FAN_CMD2_GEAR_MODE_0 | \
G762_REG_FAN_CMD2_GEAR_MODE_1)) >> 2))
struct g762_data {
struct device *hwmon_dev;
struct i2c_client *client;
struct clk *clk;
/* update mutex */
struct mutex update_lock;
/* board specific parameters. */
u32 clk_freq;
/* g762 register cache */
bool valid;
unsigned long last_updated; /* in jiffies */
u8 set_cnt; /* controls fan rotation speed in closed-loop mode */
u8 act_cnt; /* provides access to current fan RPM value */
u8 fan_sta; /* bit 0: set when actual fan speed is more than
* 25% outside requested fan speed
* bit 1: set when no transition occurs on fan
* pin for 0.7s
*/
u8 set_out; /* controls fan rotation speed in open-loop mode */
u8 fan_cmd1; /* 0: FG_PLS_ID0 FG pulses count per revolution
* 0: 2 counts per revolution
* 1: 4 counts per revolution
* 1: PWM_POLARITY 1: negative_duty
* 0: positive_duty
* 2,3: [FG_CLOCK_ID0, FG_CLK_ID1]
* 00: Divide fan clock by 1
* 01: Divide fan clock by 2
* 10: Divide fan clock by 4
* 11: Divide fan clock by 8
* 4: FAN_MODE 1:closed-loop, 0:open-loop
* 5: OUT_MODE 1:PWM, 0:DC
* 6: DET_FAN_OOC enable "fan ooc" status
* 7: DET_FAN_FAIL enable "fan fail" status
*/
u8 fan_cmd2; /* 0,1: FAN_STARTV 0,1,2,3 -> 0,32,64,96 dac_code
* 2,3: FG_GEAR_MODE
* 00: multiplier = 1
* 01: multiplier = 2
* 10: multiplier = 4
* 4: Mask ALERT# (g763 only)
*/
};
/*
* Convert count value from fan controller register (FAN_SET_CNT) into fan
* speed RPM value. Note that the datasheet documents a basic formula;
* influence of additional parameters (fan clock divisor, fan gear mode)
* have been infered from examples in the datasheet and tests.
*/
static inline unsigned int rpm_from_cnt(u8 cnt, u32 clk_freq, u16 p,
u8 clk_div, u8 gear_mult)
{
if (cnt == 0xff) /* setting cnt to 255 stops the fan */
return 0;
return (clk_freq * 30 * gear_mult) / ((cnt ? cnt : 1) * p * clk_div);
}
/*
* Convert fan RPM value from sysfs into count value for fan controller
* register (FAN_SET_CNT).
*/
static inline unsigned char cnt_from_rpm(u32 rpm, u32 clk_freq, u16 p,
u8 clk_div, u8 gear_mult)
{
if (!rpm) /* to stop the fan, set cnt to 255 */
return 0xff;
return clamp_val(((clk_freq * 30 * gear_mult) / (rpm * p * clk_div)),
0, 255);
}
/* helper to grab and cache data, at most one time per second */
static struct g762_data *g762_update_client(struct device *dev)
{
struct g762_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
int ret = 0;
mutex_lock(&data->update_lock);
if (time_before(jiffies, data->last_updated + G762_UPDATE_INTERVAL) &&
likely(data->valid))
goto out;
ret = i2c_smbus_read_byte_data(client, G762_REG_SET_CNT);
if (ret < 0)
goto out;
data->set_cnt = ret;
ret = i2c_smbus_read_byte_data(client, G762_REG_ACT_CNT);
if (ret < 0)
goto out;
data->act_cnt = ret;
ret = i2c_smbus_read_byte_data(client, G762_REG_FAN_STA);
if (ret < 0)
goto out;
data->fan_sta = ret;
ret = i2c_smbus_read_byte_data(client, G762_REG_SET_OUT);
if (ret < 0)
goto out;
data->set_out = ret;
ret = i2c_smbus_read_byte_data(client, G762_REG_FAN_CMD1);
if (ret < 0)
goto out;
data->fan_cmd1 = ret;
ret = i2c_smbus_read_byte_data(client, G762_REG_FAN_CMD2);
if (ret < 0)
goto out;
data->fan_cmd2 = ret;
data->last_updated = jiffies;
data->valid = true;
out:
mutex_unlock(&data->update_lock);
if (ret < 0) /* upon error, encode it in return value */
data = ERR_PTR(ret);
return data;
}
/* helpers for writing hardware parameters */
/*
* Set input clock frequency received on CLK pin of the chip. Accepted values
* are between 0 and 0xffffff. If zero is given, then default frequency
* (32,768Hz) is used. Note that clock frequency is a characteristic of the
* system but an internal parameter, i.e. value is not passed to the device.
*/
static int do_set_clk_freq(struct device *dev, unsigned long val)
{
struct g762_data *data = dev_get_drvdata(dev);
if (val > 0xffffff)
return -EINVAL;
if (!val)
val = 32768;
data->clk_freq = val;
return 0;
}
/* Set pwm mode. Accepts either 0 (PWM mode) or 1 (DC mode) */
static int do_set_pwm_mode(struct device *dev, unsigned long val)
{
struct g762_data *data = g762_update_client(dev);
int ret;
if (IS_ERR(data))
return PTR_ERR(data);
mutex_lock(&data->update_lock);
switch (val) {
case G762_OUT_MODE_PWM:
data->fan_cmd1 |= G762_REG_FAN_CMD1_OUT_MODE;
break;
case G762_OUT_MODE_DC:
data->fan_cmd1 &= ~G762_REG_FAN_CMD1_OUT_MODE;
break;
default:
ret = -EINVAL;
goto out;
}
ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1,
data->fan_cmd1);
data->valid = false;
out:
mutex_unlock(&data->update_lock);
return ret;
}
/* Set fan clock divisor. Accepts either 1, 2, 4 or 8. */
static int do_set_fan_div(struct device *dev, unsigned long val)
{
struct g762_data *data = g762_update_client(dev);
int ret;
if (IS_ERR(data))
return PTR_ERR(data);
mutex_lock(&data->update_lock);
switch (val) {
case 1:
data->fan_cmd1 &= ~G762_REG_FAN_CMD1_CLK_DIV_ID0;
data->fan_cmd1 &= ~G762_REG_FAN_CMD1_CLK_DIV_ID1;
break;
case 2:
data->fan_cmd1 |= G762_REG_FAN_CMD1_CLK_DIV_ID0;
data->fan_cmd1 &= ~G762_REG_FAN_CMD1_CLK_DIV_ID1;
break;
case 4:
data->fan_cmd1 &= ~G762_REG_FAN_CMD1_CLK_DIV_ID0;
data->fan_cmd1 |= G762_REG_FAN_CMD1_CLK_DIV_ID1;
break;
case 8:
data->fan_cmd1 |= G762_REG_FAN_CMD1_CLK_DIV_ID0;
data->fan_cmd1 |= G762_REG_FAN_CMD1_CLK_DIV_ID1;
break;
default:
ret = -EINVAL;
goto out;
}
ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1,
data->fan_cmd1);
data->valid = false;
out:
mutex_unlock(&data->update_lock);
return ret;
}
/* Set fan gear mode. Accepts either 0, 1 or 2. */
static int do_set_fan_gear_mode(struct device *dev, unsigned long val)
{
struct g762_data *data = g762_update_client(dev);
int ret;
if (IS_ERR(data))
return PTR_ERR(data);
mutex_lock(&data->update_lock);
switch (val) {
case 0:
data->fan_cmd2 &= ~G762_REG_FAN_CMD2_GEAR_MODE_0;
data->fan_cmd2 &= ~G762_REG_FAN_CMD2_GEAR_MODE_1;
break;
case 1:
data->fan_cmd2 |= G762_REG_FAN_CMD2_GEAR_MODE_0;
data->fan_cmd2 &= ~G762_REG_FAN_CMD2_GEAR_MODE_1;
break;
case 2:
data->fan_cmd2 &= ~G762_REG_FAN_CMD2_GEAR_MODE_0;
data->fan_cmd2 |= G762_REG_FAN_CMD2_GEAR_MODE_1;
break;
default:
ret = -EINVAL;
goto out;
}
ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD2,
data->fan_cmd2);
data->valid = false;
out:
mutex_unlock(&data->update_lock);
return ret;
}
/* Set number of fan pulses per revolution. Accepts either 2 or 4. */
static int do_set_fan_pulses(struct device *dev, unsigned long val)
{
struct g762_data *data = g762_update_client(dev);
int ret;
if (IS_ERR(data))
return PTR_ERR(data);
mutex_lock(&data->update_lock);
switch (val) {
case 2:
data->fan_cmd1 &= ~G762_REG_FAN_CMD1_PULSE_PER_REV;
break;
case 4:
data->fan_cmd1 |= G762_REG_FAN_CMD1_PULSE_PER_REV;
break;
default:
ret = -EINVAL;
goto out;
}
ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1,
data->fan_cmd1);
data->valid = false;
out:
mutex_unlock(&data->update_lock);
return ret;
}
/* Set fan mode. Accepts either 1 (open-loop) or 2 (closed-loop). */
static int do_set_pwm_enable(struct device *dev, unsigned long val)
{
struct g762_data *data = g762_update_client(dev);
int ret;
if (IS_ERR(data))
return PTR_ERR(data);
mutex_lock(&data->update_lock);
switch (val) {
case G762_FAN_MODE_CLOSED_LOOP:
data->fan_cmd1 |= G762_REG_FAN_CMD1_FAN_MODE;
break;
case G762_FAN_MODE_OPEN_LOOP:
data->fan_cmd1 &= ~G762_REG_FAN_CMD1_FAN_MODE;
/*
* BUG FIX: if SET_CNT register value is 255 then, for some
* unknown reason, fan will not rotate as expected, no matter
* the value of SET_OUT (to be specific, this seems to happen
* only in PWM mode). To workaround this bug, we give SET_CNT
* value of 254 if it is 255 when switching to open-loop.
*/
if (data->set_cnt == 0xff)
i2c_smbus_write_byte_data(data->client,
G762_REG_SET_CNT, 254);
break;
default:
ret = -EINVAL;
goto out;
}
ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1,
data->fan_cmd1);
data->valid = false;
out:
mutex_unlock(&data->update_lock);
return ret;
}
/* Set PWM polarity. Accepts either 0 (positive duty) or 1 (negative duty) */
static int do_set_pwm_polarity(struct device *dev, unsigned long val)
{
struct g762_data *data = g762_update_client(dev);
int ret;
if (IS_ERR(data))
return PTR_ERR(data);
mutex_lock(&data->update_lock);
switch (val) {
case G762_PWM_POLARITY_POSITIVE:
data->fan_cmd1 &= ~G762_REG_FAN_CMD1_PWM_POLARITY;
break;
case G762_PWM_POLARITY_NEGATIVE:
data->fan_cmd1 |= G762_REG_FAN_CMD1_PWM_POLARITY;
break;
default:
ret = -EINVAL;
goto out;
}
ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1,
data->fan_cmd1);
data->valid = false;
out:
mutex_unlock(&data->update_lock);
return ret;
}
/*
* Set pwm value. Accepts values between 0 (stops the fan) and
* 255 (full speed). This only makes sense in open-loop mode.
*/
static int do_set_pwm(struct device *dev, unsigned long val)
{
struct g762_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
int ret;
if (val > 255)
return -EINVAL;
mutex_lock(&data->update_lock);
ret = i2c_smbus_write_byte_data(client, G762_REG_SET_OUT, val);
data->valid = false;
mutex_unlock(&data->update_lock);
return ret;
}
/*
* Set fan RPM value. Can be called both in closed and open-loop mode
* but effect will only be seen after closed-loop mode is configured.
*/
static int do_set_fan_target(struct device *dev, unsigned long val)
{
struct g762_data *data = g762_update_client(dev);
int ret;
if (IS_ERR(data))
return PTR_ERR(data);
mutex_lock(&data->update_lock);
data->set_cnt = cnt_from_rpm(val, data->clk_freq,
G762_PULSE_FROM_REG(data->fan_cmd1),
G762_CLKDIV_FROM_REG(data->fan_cmd1),
G762_GEARMULT_FROM_REG(data->fan_cmd2));
ret = i2c_smbus_write_byte_data(data->client, G762_REG_SET_CNT,
data->set_cnt);
data->valid = false;
mutex_unlock(&data->update_lock);
return ret;
}
/* Set fan startup voltage. Accepted values are either 0, 1, 2 or 3. */
static int do_set_fan_startv(struct device *dev, unsigned long val)
{
struct g762_data *data = g762_update_client(dev);
int ret;
if (IS_ERR(data))
return PTR_ERR(data);
mutex_lock(&data->update_lock);
switch (val) {
case 0:
data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_0;
data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_1;
break;
case 1:
data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_0;
data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_1;
break;
case 2:
data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_0;
data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_1;
break;
case 3:
data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_0;
data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_1;
break;
default:
ret = -EINVAL;
goto out;
}
ret = i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD2,
data->fan_cmd2);
data->valid = false;
out:
mutex_unlock(&data->update_lock);
return ret;
}
/*
* Helper to import hardware characteristics from .dts file and push
* those to the chip.
*/
#ifdef CONFIG_OF
static const struct of_device_id g762_dt_match[] = {
{ .compatible = "gmt,g762" },
{ .compatible = "gmt,g763" },
{ },
};
/*
* Grab clock (a required property), enable it, get (fixed) clock frequency
* and store it. Note: upon success, clock has been prepared and enabled; it
* must later be unprepared and disabled (e.g. during module unloading) by a
* call to g762_of_clock_disable(). Note that a reference to clock is kept
* in our private data structure to be used in this function.
*/
static int g762_of_clock_enable(struct i2c_client *client)
{
struct g762_data *data;
unsigned long clk_freq;
struct clk *clk;
int ret;
if (!client->dev.of_node)
return 0;
clk = of_clk_get(client->dev.of_node, 0);
if (IS_ERR(clk)) {
dev_err(&client->dev, "failed to get clock\n");
return PTR_ERR(clk);
}
ret = clk_prepare_enable(clk);
if (ret) {
dev_err(&client->dev, "failed to enable clock\n");
goto clk_put;
}
clk_freq = clk_get_rate(clk);
ret = do_set_clk_freq(&client->dev, clk_freq);
if (ret) {
dev_err(&client->dev, "invalid clock freq %lu\n", clk_freq);
goto clk_unprep;
}
data = i2c_get_clientdata(client);
data->clk = clk;
return 0;
clk_unprep:
clk_disable_unprepare(clk);
clk_put:
clk_put(clk);
return ret;
}
static void g762_of_clock_disable(struct i2c_client *client)
{
struct g762_data *data = i2c_get_clientdata(client);
if (!data->clk)
return;
clk_disable_unprepare(data->clk);
clk_put(data->clk);
}
static int g762_of_prop_import_one(struct i2c_client *client,
const char *pname,
int (*psetter)(struct device *dev,
unsigned long val))
{
int ret;
u32 pval;
if (of_property_read_u32(client->dev.of_node, pname, &pval))
return 0;
dev_dbg(&client->dev, "found %s (%d)\n", pname, pval);
ret = (*psetter)(&client->dev, pval);
if (ret)
dev_err(&client->dev, "unable to set %s (%d)\n", pname, pval);
return ret;
}
static int g762_of_prop_import(struct i2c_client *client)
{
int ret;
if (!client->dev.of_node)
return 0;
ret = g762_of_prop_import_one(client, "fan_gear_mode",
do_set_fan_gear_mode);
if (ret)
return ret;
ret = g762_of_prop_import_one(client, "pwm_polarity",
do_set_pwm_polarity);
if (ret)
return ret;
return g762_of_prop_import_one(client, "fan_startv",
do_set_fan_startv);
}
#else
static int g762_of_prop_import(struct i2c_client *client)
{
return 0;
}
static int g762_of_clock_enable(struct i2c_client *client)
{
return 0;
}
static void g762_of_clock_disable(struct i2c_client *client) { }
#endif
/*
* Helper to import hardware characteristics from .dts file and push
* those to the chip.
*/
static int g762_pdata_prop_import(struct i2c_client *client)
{
struct g762_platform_data *pdata = dev_get_platdata(&client->dev);
int ret;
if (!pdata)
return 0;
ret = do_set_fan_gear_mode(&client->dev, pdata->fan_gear_mode);
if (ret)
return ret;
ret = do_set_pwm_polarity(&client->dev, pdata->pwm_polarity);
if (ret)
return ret;
ret = do_set_fan_startv(&client->dev, pdata->fan_startv);
if (ret)
return ret;
return do_set_clk_freq(&client->dev, pdata->clk_freq);
}
/*
* sysfs attributes
*/
/*
* Read function for fan1_input sysfs file. Return current fan RPM value, or
* 0 if fan is out of control.
*/
static ssize_t get_fan_rpm(struct device *dev, struct device_attribute *da,
char *buf)
{
struct g762_data *data = g762_update_client(dev);
unsigned int rpm = 0;
if (IS_ERR(data))
return PTR_ERR(data);
mutex_lock(&data->update_lock);
/* reverse logic: fan out of control reporting is enabled low */
if (data->fan_sta & G762_REG_FAN_STA_OOC) {
rpm = rpm_from_cnt(data->act_cnt, data->clk_freq,
G762_PULSE_FROM_REG(data->fan_cmd1),
G762_CLKDIV_FROM_REG(data->fan_cmd1),
G762_GEARMULT_FROM_REG(data->fan_cmd2));
}
mutex_unlock(&data->update_lock);
return sprintf(buf, "%u\n", rpm);
}
/*
* Read and write functions for pwm1_mode sysfs file. Get and set fan speed
* control mode i.e. PWM (1) or DC (0).
*/
static ssize_t get_pwm_mode(struct device *dev, struct device_attribute *da,
char *buf)
{
struct g762_data *data = g762_update_client(dev);
if (IS_ERR(data))
return PTR_ERR(data);
return sprintf(buf, "%d\n",
!!(data->fan_cmd1 & G762_REG_FAN_CMD1_OUT_MODE));
}
static ssize_t set_pwm_mode(struct device *dev, struct device_attribute *da,
const char *buf, size_t count)
{
unsigned long val;
int ret;
if (kstrtoul(buf, 10, &val))
return -EINVAL;
ret = do_set_pwm_mode(dev, val);
if (ret < 0)
return ret;
return count;
}
/*
* Read and write functions for fan1_div sysfs file. Get and set fan
* controller prescaler value
*/
static ssize_t get_fan_div(struct device *dev,
struct device_attribute *da, char *buf)
{
struct g762_data *data = g762_update_client(dev);
if (IS_ERR(data))
return PTR_ERR(data);
return sprintf(buf, "%d\n", G762_CLKDIV_FROM_REG(data->fan_cmd1));
}
static ssize_t set_fan_div(struct device *dev,
struct device_attribute *da,
const char *buf, size_t count)
{
unsigned long val;
int ret;
if (kstrtoul(buf, 10, &val))
return -EINVAL;
ret = do_set_fan_div(dev, val);
if (ret < 0)
return ret;
return count;
}
/*
* Read and write functions for fan1_pulses sysfs file. Get and set number
* of tachometer pulses per fan revolution.
*/
static ssize_t get_fan_pulses(struct device *dev,
struct device_attribute *da, char *buf)
{
struct g762_data *data = g762_update_client(dev);
if (IS_ERR(data))
return PTR_ERR(data);
return sprintf(buf, "%d\n", G762_PULSE_FROM_REG(data->fan_cmd1));
}
static ssize_t set_fan_pulses(struct device *dev,
struct device_attribute *da,
const char *buf, size_t count)
{
unsigned long val;
int ret;
if (kstrtoul(buf, 10, &val))
return -EINVAL;
ret = do_set_fan_pulses(dev, val);
if (ret < 0)
return ret;
return count;
}
/*
* Read and write functions for pwm1_enable. Get and set fan speed control mode
* (i.e. closed or open-loop).
*
* Following documentation about hwmon's sysfs interface, a pwm1_enable node
* should accept followings:
*
* 0 : no fan speed control (i.e. fan at full speed)
* 1 : manual fan speed control enabled (use pwm[1-*]) (open-loop)
* 2+: automatic fan speed control enabled (use fan[1-*]_target) (closed-loop)
*
* but we do not accept 0 as this mode is not natively supported by the chip
* and it is not emulated by g762 driver. -EINVAL is returned in this case.
*/
static ssize_t get_pwm_enable(struct device *dev,
struct device_attribute *da, char *buf)
{
struct g762_data *data = g762_update_client(dev);
if (IS_ERR(data))
return PTR_ERR(data);
return sprintf(buf, "%d\n",
(!!(data->fan_cmd1 & G762_REG_FAN_CMD1_FAN_MODE)) + 1);
}
static ssize_t set_pwm_enable(struct device *dev,
struct device_attribute *da,
const char *buf, size_t count)
{
unsigned long val;
int ret;
if (kstrtoul(buf, 10, &val))
return -EINVAL;
ret = do_set_pwm_enable(dev, val);
if (ret < 0)
return ret;
return count;
}
/*
* Read and write functions for pwm1 sysfs file. Get and set pwm value
* (which affects fan speed) in open-loop mode. 0 stops the fan and 255
* makes it run at full speed.
*/
static ssize_t get_pwm(struct device *dev, struct device_attribute *da,
char *buf)
{
struct g762_data *data = g762_update_client(dev);
if (IS_ERR(data))
return PTR_ERR(data);
return sprintf(buf, "%d\n", data->set_out);
}
static ssize_t set_pwm(struct device *dev, struct device_attribute *da,
const char *buf, size_t count)
{
unsigned long val;
int ret;
if (kstrtoul(buf, 10, &val))
return -EINVAL;
ret = do_set_pwm(dev, val);
if (ret < 0)
return ret;
return count;
}
/*
* Read and write function for fan1_target sysfs file. Get/set the fan speed in
* closed-loop mode. Speed is given as a RPM value; then the chip will regulate
* the fan speed using pulses from fan tachometer.
*
* Refer to rpm_from_cnt() implementation above to get info about count number
* calculation.
*
* Also note that due to rounding errors it is possible that you don't read
* back exactly the value you have set.
*/
static ssize_t get_fan_target(struct device *dev, struct device_attribute *da,
char *buf)
{
struct g762_data *data = g762_update_client(dev);
unsigned int rpm;
if (IS_ERR(data))
return PTR_ERR(data);
mutex_lock(&data->update_lock);
rpm = rpm_from_cnt(data->set_cnt, data->clk_freq,
G762_PULSE_FROM_REG(data->fan_cmd1),
G762_CLKDIV_FROM_REG(data->fan_cmd1),
G762_GEARMULT_FROM_REG(data->fan_cmd2));
mutex_unlock(&data->update_lock);
return sprintf(buf, "%u\n", rpm);
}
static ssize_t set_fan_target(struct device *dev, struct device_attribute *da,
const char *buf, size_t count)
{
unsigned long val;
int ret;
if (kstrtoul(buf, 10, &val))
return -EINVAL;
ret = do_set_fan_target(dev, val);
if (ret < 0)
return ret;
return count;
}
/* read function for fan1_fault sysfs file. */
static ssize_t get_fan_failure(struct device *dev, struct device_attribute *da,
char *buf)
{
struct g762_data *data = g762_update_client(dev);
if (IS_ERR(data))
return PTR_ERR(data);
return sprintf(buf, "%u\n", !!(data->fan_sta & G762_REG_FAN_STA_FAIL));
}
/*
* read function for fan1_alarm sysfs file. Note that OOC condition is
* enabled low
*/
static ssize_t get_fan_ooc(struct device *dev, struct device_attribute *da,
char *buf)
{
struct g762_data *data = g762_update_client(dev);
if (IS_ERR(data))
return PTR_ERR(data);
return sprintf(buf, "%u\n", !(data->fan_sta & G762_REG_FAN_STA_OOC));
}
static DEVICE_ATTR(pwm1, S_IWUSR | S_IRUGO, get_pwm, set_pwm);
static DEVICE_ATTR(pwm1_mode, S_IWUSR | S_IRUGO, get_pwm_mode, set_pwm_mode);
static DEVICE_ATTR(pwm1_enable, S_IWUSR | S_IRUGO,
get_pwm_enable, set_pwm_enable);
static DEVICE_ATTR(fan1_input, S_IRUGO, get_fan_rpm, NULL);
static DEVICE_ATTR(fan1_alarm, S_IRUGO, get_fan_ooc, NULL);
static DEVICE_ATTR(fan1_fault, S_IRUGO, get_fan_failure, NULL);
static DEVICE_ATTR(fan1_target, S_IWUSR | S_IRUGO,
get_fan_target, set_fan_target);
static DEVICE_ATTR(fan1_div, S_IWUSR | S_IRUGO, get_fan_div, set_fan_div);
static DEVICE_ATTR(fan1_pulses, S_IWUSR | S_IRUGO,
get_fan_pulses, set_fan_pulses);
/* Driver data */
static struct attribute *g762_attrs[] = {
&dev_attr_fan1_input.attr,
&dev_attr_fan1_alarm.attr,
&dev_attr_fan1_fault.attr,
&dev_attr_fan1_target.attr,
&dev_attr_fan1_div.attr,
&dev_attr_fan1_pulses.attr,
&dev_attr_pwm1.attr,
&dev_attr_pwm1_mode.attr,
&dev_attr_pwm1_enable.attr,
NULL
};
ATTRIBUTE_GROUPS(g762);
/*
* Enable both fan failure detection and fan out of control protection. The
* function does not protect change/access to data structure; it must thus
* only be called during initialization.
*/
static inline int g762_fan_init(struct device *dev)
{
struct g762_data *data = g762_update_client(dev);
if (IS_ERR(data))
return PTR_ERR(data);
data->fan_cmd1 |= G762_REG_FAN_CMD1_DET_FAN_FAIL;
data->fan_cmd1 |= G762_REG_FAN_CMD1_DET_FAN_OOC;
data->valid = false;
return i2c_smbus_write_byte_data(data->client, G762_REG_FAN_CMD1,
data->fan_cmd1);
}
static int g762_probe(struct i2c_client *client, const struct i2c_device_id *id)
{
struct device *dev = &client->dev;
struct g762_data *data;
int ret;
if (!i2c_check_functionality(client->adapter,
I2C_FUNC_SMBUS_BYTE_DATA))
return -ENODEV;
data = devm_kzalloc(dev, sizeof(struct g762_data), GFP_KERNEL);
if (!data)
return -ENOMEM;
i2c_set_clientdata(client, data);
data->client = client;
mutex_init(&data->update_lock);
/* Enable fan failure detection and fan out of control protection */
ret = g762_fan_init(dev);
if (ret)
return ret;
/* Get configuration via DT ... */
ret = g762_of_clock_enable(client);
if (ret)
return ret;
ret = g762_of_prop_import(client);
if (ret)
goto clock_dis;
/* ... or platform_data */
ret = g762_pdata_prop_import(client);
if (ret)
goto clock_dis;
data->hwmon_dev = hwmon_device_register_with_groups(dev, client->name,
data, g762_groups);
if (IS_ERR(data->hwmon_dev)) {
ret = PTR_ERR(data->hwmon_dev);
goto clock_dis;
}
return 0;
clock_dis:
g762_of_clock_disable(client);
return ret;
}
static int g762_remove(struct i2c_client *client)
{
struct g762_data *data = i2c_get_clientdata(client);
hwmon_device_unregister(data->hwmon_dev);
g762_of_clock_disable(client);
return 0;
}
static struct i2c_driver g762_driver = {
.driver = {
.name = DRVNAME,
.owner = THIS_MODULE,
.of_match_table = of_match_ptr(g762_dt_match),
},
.probe = g762_probe,
.remove = g762_remove,
.id_table = g762_id,
};
module_i2c_driver(g762_driver);
MODULE_AUTHOR("Arnaud EBALARD <arno@natisbad.org>");
MODULE_DESCRIPTION("GMT G762/G763 driver");
MODULE_LICENSE("GPL");
