+++ /dev/null
-// 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 <linux/soc/samsung/s3c-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 sysfs_emit(buf, "%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 sysfs_emit(buf, "%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");
projects / platform / kernel / linux-rpi.git / commitdiff