https://github.com/torvalds/linux
Tip revision: bcf876870b95592b52519ed4aafcf9d95999bc9c authored by Linus Torvalds on 02 August 2020, 21:21:45 UTC
Linux 5.8
Linux 5.8
Tip revision: bcf8768
gsc-hwmon.c
// SPDX-License-Identifier: GPL-2.0
/*
* Driver for Gateworks System Controller Hardware Monitor module
*
* Copyright (C) 2020 Gateworks Corporation
*/
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/mfd/gsc.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#include <linux/platform_data/gsc_hwmon.h>
#define GSC_HWMON_MAX_TEMP_CH 16
#define GSC_HWMON_MAX_IN_CH 16
#define GSC_HWMON_RESOLUTION 12
#define GSC_HWMON_VREF 2500
struct gsc_hwmon_data {
struct gsc_dev *gsc;
struct gsc_hwmon_platform_data *pdata;
struct regmap *regmap;
const struct gsc_hwmon_channel *temp_ch[GSC_HWMON_MAX_TEMP_CH];
const struct gsc_hwmon_channel *in_ch[GSC_HWMON_MAX_IN_CH];
u32 temp_config[GSC_HWMON_MAX_TEMP_CH + 1];
u32 in_config[GSC_HWMON_MAX_IN_CH + 1];
struct hwmon_channel_info temp_info;
struct hwmon_channel_info in_info;
const struct hwmon_channel_info *info[3];
struct hwmon_chip_info chip;
};
static struct regmap_bus gsc_hwmon_regmap_bus = {
.reg_read = gsc_read,
.reg_write = gsc_write,
};
static const struct regmap_config gsc_hwmon_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
.cache_type = REGCACHE_NONE,
};
static ssize_t pwm_auto_point_temp_show(struct device *dev,
struct device_attribute *devattr,
char *buf)
{
struct gsc_hwmon_data *hwmon = dev_get_drvdata(dev);
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
u8 reg = hwmon->pdata->fan_base + (2 * attr->index);
u8 regs[2];
int ret;
ret = regmap_bulk_read(hwmon->regmap, reg, regs, 2);
if (ret)
return ret;
ret = regs[0] | regs[1] << 8;
return sprintf(buf, "%d\n", ret * 10);
}
static ssize_t pwm_auto_point_temp_store(struct device *dev,
struct device_attribute *devattr,
const char *buf, size_t count)
{
struct gsc_hwmon_data *hwmon = dev_get_drvdata(dev);
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
u8 reg = hwmon->pdata->fan_base + (2 * attr->index);
u8 regs[2];
long temp;
int err;
if (kstrtol(buf, 10, &temp))
return -EINVAL;
temp = clamp_val(temp, 0, 10000);
temp = DIV_ROUND_CLOSEST(temp, 10);
regs[0] = temp & 0xff;
regs[1] = (temp >> 8) & 0xff;
err = regmap_bulk_write(hwmon->regmap, reg, regs, 2);
if (err)
return err;
return count;
}
static ssize_t pwm_auto_point_pwm_show(struct device *dev,
struct device_attribute *devattr,
char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
return sprintf(buf, "%d\n", 255 * (50 + (attr->index * 10)) / 100);
}
static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point1_pwm, pwm_auto_point_pwm, 0);
static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point1_temp, pwm_auto_point_temp, 0);
static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point2_pwm, pwm_auto_point_pwm, 1);
static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point2_temp, pwm_auto_point_temp, 1);
static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point3_pwm, pwm_auto_point_pwm, 2);
static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point3_temp, pwm_auto_point_temp, 2);
static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point4_pwm, pwm_auto_point_pwm, 3);
static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point4_temp, pwm_auto_point_temp, 3);
static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point5_pwm, pwm_auto_point_pwm, 4);
static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point5_temp, pwm_auto_point_temp, 4);
static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point6_pwm, pwm_auto_point_pwm, 5);
static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point6_temp, pwm_auto_point_temp, 5);
static struct attribute *gsc_hwmon_attributes[] = {
&sensor_dev_attr_pwm1_auto_point1_pwm.dev_attr.attr,
&sensor_dev_attr_pwm1_auto_point1_temp.dev_attr.attr,
&sensor_dev_attr_pwm1_auto_point2_pwm.dev_attr.attr,
&sensor_dev_attr_pwm1_auto_point2_temp.dev_attr.attr,
&sensor_dev_attr_pwm1_auto_point3_pwm.dev_attr.attr,
&sensor_dev_attr_pwm1_auto_point3_temp.dev_attr.attr,
&sensor_dev_attr_pwm1_auto_point4_pwm.dev_attr.attr,
&sensor_dev_attr_pwm1_auto_point4_temp.dev_attr.attr,
&sensor_dev_attr_pwm1_auto_point5_pwm.dev_attr.attr,
&sensor_dev_attr_pwm1_auto_point5_temp.dev_attr.attr,
&sensor_dev_attr_pwm1_auto_point6_pwm.dev_attr.attr,
&sensor_dev_attr_pwm1_auto_point6_temp.dev_attr.attr,
NULL
};
static const struct attribute_group gsc_hwmon_group = {
.attrs = gsc_hwmon_attributes,
};
__ATTRIBUTE_GROUPS(gsc_hwmon);
static int
gsc_hwmon_read(struct device *dev, enum hwmon_sensor_types type, u32 attr,
int channel, long *val)
{
struct gsc_hwmon_data *hwmon = dev_get_drvdata(dev);
const struct gsc_hwmon_channel *ch;
int sz, ret;
long tmp;
u8 buf[3];
switch (type) {
case hwmon_in:
ch = hwmon->in_ch[channel];
break;
case hwmon_temp:
ch = hwmon->temp_ch[channel];
break;
default:
return -EOPNOTSUPP;
}
sz = (ch->mode == mode_voltage) ? 3 : 2;
ret = regmap_bulk_read(hwmon->regmap, ch->reg, buf, sz);
if (ret)
return ret;
tmp = 0;
while (sz-- > 0)
tmp |= (buf[sz] << (8 * sz));
switch (ch->mode) {
case mode_temperature:
if (tmp > 0x8000)
tmp -= 0xffff;
break;
case mode_voltage_raw:
tmp = clamp_val(tmp, 0, BIT(GSC_HWMON_RESOLUTION));
/* scale based on ref voltage and ADC resolution */
tmp *= GSC_HWMON_VREF;
tmp >>= GSC_HWMON_RESOLUTION;
/* scale based on optional voltage divider */
if (ch->vdiv[0] && ch->vdiv[1]) {
tmp *= (ch->vdiv[0] + ch->vdiv[1]);
tmp /= ch->vdiv[1];
}
/* adjust by uV offset */
tmp += ch->mvoffset;
break;
case mode_voltage:
/* no adjustment needed */
break;
}
*val = tmp;
return 0;
}
static int
gsc_hwmon_read_string(struct device *dev, enum hwmon_sensor_types type,
u32 attr, int channel, const char **buf)
{
struct gsc_hwmon_data *hwmon = dev_get_drvdata(dev);
switch (type) {
case hwmon_in:
*buf = hwmon->in_ch[channel]->name;
break;
case hwmon_temp:
*buf = hwmon->temp_ch[channel]->name;
break;
default:
return -ENOTSUPP;
}
return 0;
}
static umode_t
gsc_hwmon_is_visible(const void *_data, enum hwmon_sensor_types type, u32 attr,
int ch)
{
return 0444;
}
static const struct hwmon_ops gsc_hwmon_ops = {
.is_visible = gsc_hwmon_is_visible,
.read = gsc_hwmon_read,
.read_string = gsc_hwmon_read_string,
};
static struct gsc_hwmon_platform_data *
gsc_hwmon_get_devtree_pdata(struct device *dev)
{
struct gsc_hwmon_platform_data *pdata;
struct gsc_hwmon_channel *ch;
struct fwnode_handle *child;
struct device_node *fan;
int nchannels;
nchannels = device_get_child_node_count(dev);
if (nchannels == 0)
return ERR_PTR(-ENODEV);
pdata = devm_kzalloc(dev,
sizeof(*pdata) + nchannels * sizeof(*ch),
GFP_KERNEL);
if (!pdata)
return ERR_PTR(-ENOMEM);
ch = (struct gsc_hwmon_channel *)(pdata + 1);
pdata->channels = ch;
pdata->nchannels = nchannels;
/* fan controller base address */
fan = of_find_compatible_node(dev->parent->of_node, NULL, "gw,gsc-fan");
if (fan && of_property_read_u32(fan, "reg", &pdata->fan_base)) {
dev_err(dev, "fan node without base\n");
return ERR_PTR(-EINVAL);
}
/* allocate structures for channels and count instances of each type */
device_for_each_child_node(dev, child) {
if (fwnode_property_read_string(child, "label", &ch->name)) {
dev_err(dev, "channel without label\n");
fwnode_handle_put(child);
return ERR_PTR(-EINVAL);
}
if (fwnode_property_read_u32(child, "reg", &ch->reg)) {
dev_err(dev, "channel without reg\n");
fwnode_handle_put(child);
return ERR_PTR(-EINVAL);
}
if (fwnode_property_read_u32(child, "gw,mode", &ch->mode)) {
dev_err(dev, "channel without mode\n");
fwnode_handle_put(child);
return ERR_PTR(-EINVAL);
}
if (ch->mode > mode_max) {
dev_err(dev, "invalid channel mode\n");
fwnode_handle_put(child);
return ERR_PTR(-EINVAL);
}
if (!fwnode_property_read_u32(child,
"gw,voltage-offset-microvolt",
&ch->mvoffset))
ch->mvoffset /= 1000;
fwnode_property_read_u32_array(child,
"gw,voltage-divider-ohms",
ch->vdiv, ARRAY_SIZE(ch->vdiv));
ch++;
}
return pdata;
}
static int gsc_hwmon_probe(struct platform_device *pdev)
{
struct gsc_dev *gsc = dev_get_drvdata(pdev->dev.parent);
struct device *dev = &pdev->dev;
struct device *hwmon_dev;
struct gsc_hwmon_platform_data *pdata = dev_get_platdata(dev);
struct gsc_hwmon_data *hwmon;
const struct attribute_group **groups;
int i, i_in, i_temp;
if (!pdata) {
pdata = gsc_hwmon_get_devtree_pdata(dev);
if (IS_ERR(pdata))
return PTR_ERR(pdata);
}
hwmon = devm_kzalloc(dev, sizeof(*hwmon), GFP_KERNEL);
if (!hwmon)
return -ENOMEM;
hwmon->gsc = gsc;
hwmon->pdata = pdata;
hwmon->regmap = devm_regmap_init(dev, &gsc_hwmon_regmap_bus,
gsc->i2c_hwmon,
&gsc_hwmon_regmap_config);
if (IS_ERR(hwmon->regmap))
return PTR_ERR(hwmon->regmap);
for (i = 0, i_in = 0, i_temp = 0; i < hwmon->pdata->nchannels; i++) {
const struct gsc_hwmon_channel *ch = &pdata->channels[i];
switch (ch->mode) {
case mode_temperature:
if (i_temp == GSC_HWMON_MAX_TEMP_CH) {
dev_err(gsc->dev, "too many temp channels\n");
return -EINVAL;
}
hwmon->temp_ch[i_temp] = ch;
hwmon->temp_config[i_temp] = HWMON_T_INPUT |
HWMON_T_LABEL;
i_temp++;
break;
case mode_voltage:
case mode_voltage_raw:
if (i_in == GSC_HWMON_MAX_IN_CH) {
dev_err(gsc->dev, "too many input channels\n");
return -EINVAL;
}
hwmon->in_ch[i_in] = ch;
hwmon->in_config[i_in] =
HWMON_I_INPUT | HWMON_I_LABEL;
i_in++;
break;
default:
dev_err(gsc->dev, "invalid mode: %d\n", ch->mode);
return -EINVAL;
}
}
/* setup config structures */
hwmon->chip.ops = &gsc_hwmon_ops;
hwmon->chip.info = hwmon->info;
hwmon->info[0] = &hwmon->temp_info;
hwmon->info[1] = &hwmon->in_info;
hwmon->temp_info.type = hwmon_temp;
hwmon->temp_info.config = hwmon->temp_config;
hwmon->in_info.type = hwmon_in;
hwmon->in_info.config = hwmon->in_config;
groups = pdata->fan_base ? gsc_hwmon_groups : NULL;
hwmon_dev = devm_hwmon_device_register_with_info(dev,
KBUILD_MODNAME, hwmon,
&hwmon->chip, groups);
return PTR_ERR_OR_ZERO(hwmon_dev);
}
static const struct of_device_id gsc_hwmon_of_match[] = {
{ .compatible = "gw,gsc-adc", },
{}
};
static struct platform_driver gsc_hwmon_driver = {
.driver = {
.name = "gsc-hwmon",
.of_match_table = gsc_hwmon_of_match,
},
.probe = gsc_hwmon_probe,
};
module_platform_driver(gsc_hwmon_driver);
MODULE_AUTHOR("Tim Harvey <tharvey@gateworks.com>");
MODULE_DESCRIPTION("GSC hardware monitor driver");
MODULE_LICENSE("GPL v2");