/*
* pwm-fan.c - driver for fans connected to PWM lines.
*
* Copyright (c) 2014 .
*
* Author: Geroge
*
* 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.
*/
#ifdef HWMON
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#endif
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pwm.h>
#include <linux/sysfs.h>
#include <linux/thermal.h>
#define MAX_PWM 255
struct pwm_fan_ctx {
struct mutex lock;
struct device *dev; //
struct pwm_device *pwm;
unsigned int pwm_value;
unsigned int pwm_fan_state;
unsigned int pwm_fan_max_state;
unsigned int *pwm_fan_cooling_levels;
struct thermal_cooling_device *cdev;
};
static int __set_pwm(struct pwm_fan_ctx *ctx, unsigned long pwm)
{
unsigned long duty;
int ret = 0;
// dump_stack();
// printk("__set_pwm pwm:%ld\n",pwm);
mutex_lock(&ctx->lock);
if (ctx->pwm_value == pwm)
goto exit_set_pwm_err;
duty = DIV_ROUND_UP(pwm * (ctx->pwm->args.period - 1), MAX_PWM);
// printk("__set_pwm duty:%ld,%d\n",duty,ctx->pwm->args.period);
ret = pwm_config(ctx->pwm, duty, ctx->pwm->args.period);
if (ret)
goto exit_set_pwm_err;
if (pwm == 0)
pwm_disable(ctx->pwm);
if (ctx->pwm_value == 0) {
ret = pwm_enable(ctx->pwm);
if (ret)
goto exit_set_pwm_err;
}
ctx->pwm_value = pwm;
exit_set_pwm_err:
mutex_unlock(&ctx->lock);
return ret;
}
#ifdef HWMON
static void pwm_fan_update_state(struct pwm_fan_ctx *ctx, unsigned long pwm)
{
int i;
for (i = 0; i < ctx->pwm_fan_max_state; ++i)
if (pwm < ctx->pwm_fan_cooling_levels[i + 1])
break;
ctx->pwm_fan_state = i;
}
static ssize_t set_pwm(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct pwm_fan_ctx *ctx = dev_get_drvdata(dev);
unsigned long pwm;
int ret;
if (kstrtoul(buf, 10, &pwm) || pwm > MAX_PWM)
return -EINVAL;
printk("set_pwm pwm:%ld\n",pwm);
ret = __set_pwm(ctx, pwm);
if (ret)
return ret;
pwm_fan_update_state(ctx, pwm);
return count;
}
static ssize_t show_pwm(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct pwm_fan_ctx *ctx = dev_get_drvdata(dev);
return sprintf(buf, "%u\n", ctx->pwm_value);
}
static SENSOR_DEVICE_ATTR(pwm1, S_IRUGO | S_IWUSR, show_pwm, set_pwm, 0);
static struct attribute *pwm_fan_attrs[] = {
&sensor_dev_attr_pwm1.dev_attr.attr,
NULL,
};
ATTRIBUTE_GROUPS(pwm_fan);
#endif
/* thermal cooling device callbacks */
static int pwm_fan_get_max_state(struct thermal_cooling_device *cdev,
unsigned long *state)
{
struct pwm_fan_ctx *ctx = cdev->devdata;
if (!ctx)
return -EINVAL;
*state = ctx->pwm_fan_max_state;
return 0;
}
static int pwm_fan_get_cur_state(struct thermal_cooling_device *cdev,
unsigned long *state)
{
struct pwm_fan_ctx *ctx = cdev->devdata;
if (!ctx)
return -EINVAL;
*state = ctx->pwm_fan_state;
return 0;
}
static int
pwm_fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state)
{
struct pwm_fan_ctx *ctx = cdev->devdata;
int ret;
#if 0
struct thermal_instance *instance;
mutex_lock(&cdev->lock);
/* Make sure cdev enters the deepest cooling state */
list_for_each_entry(instance, &cdev->thermal_instances, cdev_node) {
dev_err(&cdev->device, "temperature:%d\n",instance->tz->temperature);
}
mutex_unlock(&cdev->lock);
#endif
if (!ctx || (state > ctx->pwm_fan_max_state))
return -EINVAL;
if (state == ctx->pwm_fan_state)
return 0;
ret = __set_pwm(ctx, ctx->pwm_fan_cooling_levels[state]);
if (ret) {
dev_err(&cdev->device, "Cannot set pwm!\n");
return ret;
}
ctx->pwm_fan_state = state;
return ret;
}
//
static int pwm_fan_get_requested_power(struct thermal_cooling_device *cdev,
struct thermal_zone_device *tz,
u32 *power)
{
return 0;
}
static int pwm_fan_state2power(struct thermal_cooling_device *cdev,
struct thermal_zone_device *tz,
unsigned long state,
u32 *power)
{
return 0;
}
static int pwm_fan_power2state(struct thermal_cooling_device *cdev,
struct thermal_zone_device *tz,
u32 power, unsigned long *state)
{
#if 0
struct pwm_fan_ctx *ctx = cdev->devdata;
int ret;
printk("pwm_fan_set_cur_state state : %ld\n",state);
if (!ctx || (state > ctx->pwm_fan_max_state))
return -EINVAL;
if (state == ctx->pwm_fan_state)
return 0;
ret = __set_pwm(ctx, ctx->pwm_fan_cooling_levels[state]);
if (ret) {
dev_err(&cdev->device, "Cannot set pwm!\n");
return ret;
}
ctx->pwm_fan_state = state;
#endif
// printk("tz->temperature:%d\n",tz->temperature);
if(tz->temperature > 70000 && tz->temperature <= 80000)
{
*state = 1;
}
else if(tz->temperature > 80000 && tz->temperature <= 100000)
{
*state = 2;
}
else if(tz->temperature > 100000 && tz->temperature <= 114000)
{
*state = 3;
}
return 0;
}
static int pwm_fan_monitor_fan(int temperature,unsigned long *state)
{
if(temperature < 50000)
{
*state = 0;
}
else if(temperature > 70000 && temperature <= 75000)
{
*state = 1;
}
else if(temperature > 75000 && temperature <= 100000)
{
*state = 2;
}
else if(temperature > 100000 && temperature <= 114000)
{
*state = 3;
}
return 0;
}
//end
static const struct thermal_cooling_device_ops pwm_fan_cooling_ops = {
.get_max_state = pwm_fan_get_max_state,
.get_cur_state = pwm_fan_get_cur_state,
.set_cur_state = pwm_fan_set_cur_state,
//
.get_requested_power = pwm_fan_get_requested_power,
.state2power = pwm_fan_state2power,
.power2state = pwm_fan_power2state,
.monitor_fan = pwm_fan_monitor_fan,
//end
};
static int pwm_fan_of_get_cooling_data(struct device *dev,
struct pwm_fan_ctx *ctx)
{
struct device_node *np = dev->of_node;
int num, i, ret;
if (!of_find_property(np, "cooling-levels", NULL))
return 0;
ret = of_property_count_u32_elems(np, "cooling-levels");
if (ret <= 0) {
dev_err(dev, "Wrong data!\n");
return ret ? : -EINVAL;
}
num = ret;
ctx->pwm_fan_cooling_levels = devm_kzalloc(dev, num * sizeof(u32),
GFP_KERNEL);
if (!ctx->pwm_fan_cooling_levels)
return -ENOMEM;
ret = of_property_read_u32_array(np, "cooling-levels",
ctx->pwm_fan_cooling_levels, num);
if (ret) {
dev_err(dev, "Property 'cooling-levels' cannot be read!\n");
return ret;
}
for (i = 0; i < num; i++) {
if (ctx->pwm_fan_cooling_levels[i] > MAX_PWM) {
dev_err(dev, "PWM fan state[%d]:%d > %d\n", i,
ctx->pwm_fan_cooling_levels[i], MAX_PWM);
return -EINVAL;
}
}
ctx->pwm_fan_max_state = num - 1;
return 0;
}
static int pwm_fan_probe(struct platform_device *pdev)
{
struct thermal_cooling_device *cdev;
struct pwm_fan_ctx *ctx;
#ifdef HWMON
struct device *hwmon;
#endif
int duty_cycle;
int ret;
ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
if (!ctx)
return -ENOMEM;
mutex_init(&ctx->lock);
ctx->dev = &pdev->dev;
ctx->pwm = devm_of_pwm_get(&pdev->dev, pdev->dev.of_node, NULL);
if (IS_ERR(ctx->pwm)) {
dev_err(&pdev->dev, "Could not get PWM\n");
return PTR_ERR(ctx->pwm);
}
#if 0
ctx->pwm = devm_pwm_get(&pdev->dev, NULL);
if (IS_ERR(ctx->pwm) && PTR_ERR(ctx->pwm) != -EPROBE_DEFER) {
dev_err(&pdev->dev, "unable to request PWM, trying devm_of_pwm_get\n");
return PTR_ERR(ctx->pwm);
// ctx->pwm = devm_of_pwm_get(&pdev->dev, pdev->dev.of_node, NULL);
// if (IS_
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