linux/drivers/hwmon/s3c-hwmon.c
Thomas Gleixner 4505153954 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 333
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation 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 inc 59 temple place suite 330 boston ma 02111
  1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 136 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190530000436.384967451@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:37:06 +02:00

380 lines
9.9 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/* linux/drivers/hwmon/s3c-hwmon.c
*
* Copyright (C) 2005, 2008, 2009 Simtec Electronics
* http://armlinux.simtec.co.uk/
* Ben Dooks <ben@simtec.co.uk>
*
* S3C24XX/S3C64XX ADC hwmon support
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <plat/adc.h>
#include <linux/platform_data/hwmon-s3c.h>
struct s3c_hwmon_attr {
struct sensor_device_attribute in;
struct sensor_device_attribute label;
char in_name[12];
char label_name[12];
};
/**
* struct s3c_hwmon - ADC hwmon client information
* @lock: Access lock to serialise the conversions.
* @client: The client we registered with the S3C ADC core.
* @hwmon_dev: The hwmon device we created.
* @attr: The holders for the channel attributes.
*/
struct s3c_hwmon {
struct mutex lock;
struct s3c_adc_client *client;
struct device *hwmon_dev;
struct s3c_hwmon_attr attrs[8];
};
/**
* s3c_hwmon_read_ch - read a value from a given adc channel.
* @dev: The device.
* @hwmon: Our state.
* @channel: The channel we're reading from.
*
* Read a value from the @channel with the proper locking and sleep until
* either the read completes or we timeout awaiting the ADC core to get
* back to us.
*/
static int s3c_hwmon_read_ch(struct device *dev,
struct s3c_hwmon *hwmon, int channel)
{
int ret;
ret = mutex_lock_interruptible(&hwmon->lock);
if (ret < 0)
return ret;
dev_dbg(dev, "reading channel %d\n", channel);
ret = s3c_adc_read(hwmon->client, channel);
mutex_unlock(&hwmon->lock);
return ret;
}
#ifdef CONFIG_SENSORS_S3C_RAW
/**
* s3c_hwmon_show_raw - show a conversion from the raw channel number.
* @dev: The device that the attribute belongs to.
* @attr: The attribute being read.
* @buf: The result buffer.
*
* This show deals with the raw attribute, registered for each possible
* ADC channel. This does a conversion and returns the raw (un-scaled)
* value returned from the hardware.
*/
static ssize_t s3c_hwmon_show_raw(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct s3c_hwmon *adc = dev_get_drvdata(dev);
struct sensor_device_attribute *sa = to_sensor_dev_attr(attr);
int ret;
ret = s3c_hwmon_read_ch(dev, adc, sa->index);
return (ret < 0) ? ret : snprintf(buf, PAGE_SIZE, "%d\n", ret);
}
static SENSOR_DEVICE_ATTR(adc0_raw, S_IRUGO, s3c_hwmon_show_raw, NULL, 0);
static SENSOR_DEVICE_ATTR(adc1_raw, S_IRUGO, s3c_hwmon_show_raw, NULL, 1);
static SENSOR_DEVICE_ATTR(adc2_raw, S_IRUGO, s3c_hwmon_show_raw, NULL, 2);
static SENSOR_DEVICE_ATTR(adc3_raw, S_IRUGO, s3c_hwmon_show_raw, NULL, 3);
static SENSOR_DEVICE_ATTR(adc4_raw, S_IRUGO, s3c_hwmon_show_raw, NULL, 4);
static SENSOR_DEVICE_ATTR(adc5_raw, S_IRUGO, s3c_hwmon_show_raw, NULL, 5);
static SENSOR_DEVICE_ATTR(adc6_raw, S_IRUGO, s3c_hwmon_show_raw, NULL, 6);
static SENSOR_DEVICE_ATTR(adc7_raw, S_IRUGO, s3c_hwmon_show_raw, NULL, 7);
static struct attribute *s3c_hwmon_attrs[9] = {
&sensor_dev_attr_adc0_raw.dev_attr.attr,
&sensor_dev_attr_adc1_raw.dev_attr.attr,
&sensor_dev_attr_adc2_raw.dev_attr.attr,
&sensor_dev_attr_adc3_raw.dev_attr.attr,
&sensor_dev_attr_adc4_raw.dev_attr.attr,
&sensor_dev_attr_adc5_raw.dev_attr.attr,
&sensor_dev_attr_adc6_raw.dev_attr.attr,
&sensor_dev_attr_adc7_raw.dev_attr.attr,
NULL,
};
static struct attribute_group s3c_hwmon_attrgroup = {
.attrs = s3c_hwmon_attrs,
};
static inline int s3c_hwmon_add_raw(struct device *dev)
{
return sysfs_create_group(&dev->kobj, &s3c_hwmon_attrgroup);
}
static inline void s3c_hwmon_remove_raw(struct device *dev)
{
sysfs_remove_group(&dev->kobj, &s3c_hwmon_attrgroup);
}
#else
static inline int s3c_hwmon_add_raw(struct device *dev) { return 0; }
static inline void s3c_hwmon_remove_raw(struct device *dev) { }
#endif /* CONFIG_SENSORS_S3C_RAW */
/**
* s3c_hwmon_ch_show - show value of a given channel
* @dev: The device that the attribute belongs to.
* @attr: The attribute being read.
* @buf: The result buffer.
*
* Read a value from the ADC and scale it before returning it to the
* caller. The scale factor is gained from the channel configuration
* passed via the platform data when the device was registered.
*/
static ssize_t s3c_hwmon_ch_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct sensor_device_attribute *sen_attr = to_sensor_dev_attr(attr);
struct s3c_hwmon *hwmon = dev_get_drvdata(dev);
struct s3c_hwmon_pdata *pdata = dev_get_platdata(dev);
struct s3c_hwmon_chcfg *cfg;
int ret;
cfg = pdata->in[sen_attr->index];
ret = s3c_hwmon_read_ch(dev, hwmon, sen_attr->index);
if (ret < 0)
return ret;
ret *= cfg->mult;
ret = DIV_ROUND_CLOSEST(ret, cfg->div);
return snprintf(buf, PAGE_SIZE, "%d\n", ret);
}
/**
* s3c_hwmon_label_show - show label name of the given channel.
* @dev: The device that the attribute belongs to.
* @attr: The attribute being read.
* @buf: The result buffer.
*
* Return the label name of a given channel
*/
static ssize_t s3c_hwmon_label_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct sensor_device_attribute *sen_attr = to_sensor_dev_attr(attr);
struct s3c_hwmon_pdata *pdata = dev_get_platdata(dev);
struct s3c_hwmon_chcfg *cfg;
cfg = pdata->in[sen_attr->index];
return snprintf(buf, PAGE_SIZE, "%s\n", cfg->name);
}
/**
* s3c_hwmon_create_attr - create hwmon attribute for given channel.
* @dev: The device to create the attribute on.
* @cfg: The channel configuration passed from the platform data.
* @channel: The ADC channel number to process.
*
* Create the scaled attribute for use with hwmon from the specified
* platform data in @pdata. The sysfs entry is handled by the routine
* s3c_hwmon_ch_show().
*
* The attribute name is taken from the configuration data if present
* otherwise the name is taken by concatenating in_ with the channel
* number.
*/
static int s3c_hwmon_create_attr(struct device *dev,
struct s3c_hwmon_chcfg *cfg,
struct s3c_hwmon_attr *attrs,
int channel)
{
struct sensor_device_attribute *attr;
int ret;
snprintf(attrs->in_name, sizeof(attrs->in_name), "in%d_input", channel);
attr = &attrs->in;
attr->index = channel;
sysfs_attr_init(&attr->dev_attr.attr);
attr->dev_attr.attr.name = attrs->in_name;
attr->dev_attr.attr.mode = S_IRUGO;
attr->dev_attr.show = s3c_hwmon_ch_show;
ret = device_create_file(dev, &attr->dev_attr);
if (ret < 0) {
dev_err(dev, "failed to create input attribute\n");
return ret;
}
/* if this has a name, add a label */
if (cfg->name) {
snprintf(attrs->label_name, sizeof(attrs->label_name),
"in%d_label", channel);
attr = &attrs->label;
attr->index = channel;
sysfs_attr_init(&attr->dev_attr.attr);
attr->dev_attr.attr.name = attrs->label_name;
attr->dev_attr.attr.mode = S_IRUGO;
attr->dev_attr.show = s3c_hwmon_label_show;
ret = device_create_file(dev, &attr->dev_attr);
if (ret < 0) {
device_remove_file(dev, &attrs->in.dev_attr);
dev_err(dev, "failed to create label attribute\n");
}
}
return ret;
}
static void s3c_hwmon_remove_attr(struct device *dev,
struct s3c_hwmon_attr *attrs)
{
device_remove_file(dev, &attrs->in.dev_attr);
device_remove_file(dev, &attrs->label.dev_attr);
}
/**
* s3c_hwmon_probe - device probe entry.
* @dev: The device being probed.
*/
static int s3c_hwmon_probe(struct platform_device *dev)
{
struct s3c_hwmon_pdata *pdata = dev_get_platdata(&dev->dev);
struct s3c_hwmon *hwmon;
int ret = 0;
int i;
if (!pdata) {
dev_err(&dev->dev, "no platform data supplied\n");
return -EINVAL;
}
hwmon = devm_kzalloc(&dev->dev, sizeof(struct s3c_hwmon), GFP_KERNEL);
if (hwmon == NULL)
return -ENOMEM;
platform_set_drvdata(dev, hwmon);
mutex_init(&hwmon->lock);
/* Register with the core ADC driver. */
hwmon->client = s3c_adc_register(dev, NULL, NULL, 0);
if (IS_ERR(hwmon->client)) {
dev_err(&dev->dev, "cannot register adc\n");
return PTR_ERR(hwmon->client);
}
/* add attributes for our adc devices. */
ret = s3c_hwmon_add_raw(&dev->dev);
if (ret)
goto err_registered;
/* register with the hwmon core */
hwmon->hwmon_dev = hwmon_device_register(&dev->dev);
if (IS_ERR(hwmon->hwmon_dev)) {
dev_err(&dev->dev, "error registering with hwmon\n");
ret = PTR_ERR(hwmon->hwmon_dev);
goto err_raw_attribute;
}
for (i = 0; i < ARRAY_SIZE(pdata->in); i++) {
struct s3c_hwmon_chcfg *cfg = pdata->in[i];
if (!cfg)
continue;
if (cfg->mult >= 0x10000)
dev_warn(&dev->dev,
"channel %d multiplier too large\n",
i);
if (cfg->div == 0) {
dev_err(&dev->dev, "channel %d divider zero\n", i);
continue;
}
ret = s3c_hwmon_create_attr(&dev->dev, pdata->in[i],
&hwmon->attrs[i], i);
if (ret) {
dev_err(&dev->dev,
"error creating channel %d\n", i);
for (i--; i >= 0; i--)
s3c_hwmon_remove_attr(&dev->dev,
&hwmon->attrs[i]);
goto err_hwmon_register;
}
}
return 0;
err_hwmon_register:
hwmon_device_unregister(hwmon->hwmon_dev);
err_raw_attribute:
s3c_hwmon_remove_raw(&dev->dev);
err_registered:
s3c_adc_release(hwmon->client);
return ret;
}
static int s3c_hwmon_remove(struct platform_device *dev)
{
struct s3c_hwmon *hwmon = platform_get_drvdata(dev);
int i;
s3c_hwmon_remove_raw(&dev->dev);
for (i = 0; i < ARRAY_SIZE(hwmon->attrs); i++)
s3c_hwmon_remove_attr(&dev->dev, &hwmon->attrs[i]);
hwmon_device_unregister(hwmon->hwmon_dev);
s3c_adc_release(hwmon->client);
return 0;
}
static struct platform_driver s3c_hwmon_driver = {
.driver = {
.name = "s3c-hwmon",
},
.probe = s3c_hwmon_probe,
.remove = s3c_hwmon_remove,
};
module_platform_driver(s3c_hwmon_driver);
MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
MODULE_DESCRIPTION("S3C ADC HWMon driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:s3c-hwmon");