hwmon: (gxp-fan-ctrl) Add GXP fan controller

The GXP SoC can support up to 16 fans through the interface provided by
the CPLD. The current support is limited to 8 fans. The fans speeds are
controlled via 8 different PWMs which can vary in value from  0-255. The
fans are also capable of reporting if they have failed to the CPLD which
in turn reports the status to the GXP SoC.

Signed-off-by: Nick Hawkins <nick.hawkins@hpe.com>
Link: https://lore.kernel.org/r/20230103203654.59322-2-nick.hawkins@hpe.com
[groeck: Improved alignment of defined, added missing include linux/bits.h]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This commit is contained in:
Nick Hawkins 2023-01-03 14:36:50 -06:00 committed by Guenter Roeck
parent 6d03bbff45
commit 90905f7c40
5 changed files with 294 additions and 0 deletions

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@ -0,0 +1,28 @@
.. SPDX-License-Identifier: GPL-2.0-only
Kernel driver gxp-fan-ctrl
==========================
Supported chips:
* HPE GXP SOC
Author: Nick Hawkins <nick.hawkins@hpe.com>
Description
-----------
gxp-fan-ctrl is a driver which provides fan control for the hpe gxp soc.
The driver allows the gathering of fan status and the use of fan
PWM control.
Sysfs attributes
----------------
======================= ===========================================================
pwm[0-7] Fan 0 to 7 respective PWM value (0-255)
fan[0-7]_fault Fan 0 to 7 respective fault status: 1 fail, 0 ok
fan[0-7]_enable Fan 0 to 7 respective enabled status: 1 enabled, 0 disabled
======================= ===========================================================

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@ -73,6 +73,7 @@ Hardware Monitoring Kernel Drivers
g762
gsc-hwmon
gl518sm
gxp-fan-ctrl
hih6130
ibmaem
ibm-cffps

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@ -714,6 +714,15 @@ config SENSORS_GPIO_FAN
This driver can also be built as a module. If so, the module
will be called gpio-fan.
config SENSORS_GXP_FAN_CTRL
tristate "HPE GXP fan controller"
depends on ARCH_HPE_GXP || COMPILE_TEST
help
If you say yes here you get support for GXP fan control functionality.
The GXP controls fan function via the CPLD through the use of PWM
registers. This driver reports status and pwm setting of the fans.
config SENSORS_HIH6130
tristate "Honeywell Humidicon HIH-6130 humidity/temperature sensor"
depends on I2C

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@ -83,6 +83,7 @@ obj-$(CONFIG_SENSORS_GL518SM) += gl518sm.o
obj-$(CONFIG_SENSORS_GL520SM) += gl520sm.o
obj-$(CONFIG_SENSORS_GSC) += gsc-hwmon.o
obj-$(CONFIG_SENSORS_GPIO_FAN) += gpio-fan.o
obj-$(CONFIG_SENSORS_GXP_FAN_CTRL) += gxp-fan-ctrl.o
obj-$(CONFIG_SENSORS_HIH6130) += hih6130.o
obj-$(CONFIG_SENSORS_ULTRA45) += ultra45_env.o
obj-$(CONFIG_SENSORS_I5500) += i5500_temp.o

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@ -0,0 +1,255 @@
// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (C) 2022 Hewlett-Packard Enterprise Development Company, L.P. */
#include <linux/bits.h>
#include <linux/err.h>
#include <linux/hwmon.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#define OFS_FAN_INST 0 /* Is 0 because plreg base will be set at INST */
#define OFS_FAN_FAIL 2 /* Is 2 bytes after base */
#define OFS_SEVSTAT 0 /* Is 0 because fn2 base will be set at SEVSTAT */
#define POWER_BIT 24
struct gxp_fan_ctrl_drvdata {
void __iomem *base;
void __iomem *plreg;
void __iomem *fn2;
};
static bool fan_installed(struct device *dev, int fan)
{
struct gxp_fan_ctrl_drvdata *drvdata = dev_get_drvdata(dev);
u8 val;
val = readb(drvdata->plreg + OFS_FAN_INST);
return !!(val & BIT(fan));
}
static long fan_failed(struct device *dev, int fan)
{
struct gxp_fan_ctrl_drvdata *drvdata = dev_get_drvdata(dev);
u8 val;
val = readb(drvdata->plreg + OFS_FAN_FAIL);
return !!(val & BIT(fan));
}
static long fan_enabled(struct device *dev, int fan)
{
struct gxp_fan_ctrl_drvdata *drvdata = dev_get_drvdata(dev);
u32 val;
/*
* Check the power status as if the platform is off the value
* reported for the PWM will be incorrect. Report fan as
* disabled.
*/
val = readl(drvdata->fn2 + OFS_SEVSTAT);
return !!((val & BIT(POWER_BIT)) && fan_installed(dev, fan));
}
static int gxp_pwm_write(struct device *dev, u32 attr, int channel, long val)
{
struct gxp_fan_ctrl_drvdata *drvdata = dev_get_drvdata(dev);
switch (attr) {
case hwmon_pwm_input:
if (val > 255 || val < 0)
return -EINVAL;
writeb(val, drvdata->base + channel);
return 0;
default:
return -EOPNOTSUPP;
}
}
static int gxp_fan_ctrl_write(struct device *dev, enum hwmon_sensor_types type,
u32 attr, int channel, long val)
{
switch (type) {
case hwmon_pwm:
return gxp_pwm_write(dev, attr, channel, val);
default:
return -EOPNOTSUPP;
}
}
static int gxp_fan_read(struct device *dev, u32 attr, int channel, long *val)
{
switch (attr) {
case hwmon_fan_enable:
*val = fan_enabled(dev, channel);
return 0;
case hwmon_fan_fault:
*val = fan_failed(dev, channel);
return 0;
default:
return -EOPNOTSUPP;
}
}
static int gxp_pwm_read(struct device *dev, u32 attr, int channel, long *val)
{
struct gxp_fan_ctrl_drvdata *drvdata = dev_get_drvdata(dev);
u32 reg;
/*
* Check the power status of the platform. If the platform is off
* the value reported for the PWM will be incorrect. In this case
* report a PWM of zero.
*/
reg = readl(drvdata->fn2 + OFS_SEVSTAT);
if (reg & BIT(POWER_BIT))
*val = fan_installed(dev, channel) ? readb(drvdata->base + channel) : 0;
else
*val = 0;
return 0;
}
static int gxp_fan_ctrl_read(struct device *dev, enum hwmon_sensor_types type,
u32 attr, int channel, long *val)
{
switch (type) {
case hwmon_fan:
return gxp_fan_read(dev, attr, channel, val);
case hwmon_pwm:
return gxp_pwm_read(dev, attr, channel, val);
default:
return -EOPNOTSUPP;
}
}
static umode_t gxp_fan_ctrl_is_visible(const void *_data,
enum hwmon_sensor_types type,
u32 attr, int channel)
{
umode_t mode = 0;
switch (type) {
case hwmon_fan:
switch (attr) {
case hwmon_fan_enable:
case hwmon_fan_fault:
mode = 0444;
break;
default:
break;
}
break;
case hwmon_pwm:
switch (attr) {
case hwmon_pwm_input:
mode = 0644;
break;
default:
break;
}
break;
default:
break;
}
return mode;
}
static const struct hwmon_ops gxp_fan_ctrl_ops = {
.is_visible = gxp_fan_ctrl_is_visible,
.read = gxp_fan_ctrl_read,
.write = gxp_fan_ctrl_write,
};
static const struct hwmon_channel_info *gxp_fan_ctrl_info[] = {
HWMON_CHANNEL_INFO(fan,
HWMON_F_FAULT | HWMON_F_ENABLE,
HWMON_F_FAULT | HWMON_F_ENABLE,
HWMON_F_FAULT | HWMON_F_ENABLE,
HWMON_F_FAULT | HWMON_F_ENABLE,
HWMON_F_FAULT | HWMON_F_ENABLE,
HWMON_F_FAULT | HWMON_F_ENABLE,
HWMON_F_FAULT | HWMON_F_ENABLE,
HWMON_F_FAULT | HWMON_F_ENABLE),
HWMON_CHANNEL_INFO(pwm,
HWMON_PWM_INPUT,
HWMON_PWM_INPUT,
HWMON_PWM_INPUT,
HWMON_PWM_INPUT,
HWMON_PWM_INPUT,
HWMON_PWM_INPUT,
HWMON_PWM_INPUT,
HWMON_PWM_INPUT),
NULL
};
static const struct hwmon_chip_info gxp_fan_ctrl_chip_info = {
.ops = &gxp_fan_ctrl_ops,
.info = gxp_fan_ctrl_info,
};
static int gxp_fan_ctrl_probe(struct platform_device *pdev)
{
struct gxp_fan_ctrl_drvdata *drvdata;
struct resource *res;
struct device *dev = &pdev->dev;
struct device *hwmon_dev;
drvdata = devm_kzalloc(dev, sizeof(struct gxp_fan_ctrl_drvdata),
GFP_KERNEL);
if (!drvdata)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
drvdata->base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(drvdata->base))
return dev_err_probe(dev, PTR_ERR(drvdata->base),
"failed to map base\n");
drvdata->plreg = devm_platform_ioremap_resource_byname(pdev,
"pl");
if (IS_ERR(drvdata->plreg))
return dev_err_probe(dev, PTR_ERR(drvdata->plreg),
"failed to map plreg\n");
drvdata->fn2 = devm_platform_ioremap_resource_byname(pdev,
"fn2");
if (IS_ERR(drvdata->fn2))
return dev_err_probe(dev, PTR_ERR(drvdata->fn2),
"failed to map fn2\n");
hwmon_dev = devm_hwmon_device_register_with_info(&pdev->dev,
"hpe_gxp_fan_ctrl",
drvdata,
&gxp_fan_ctrl_chip_info,
NULL);
return PTR_ERR_OR_ZERO(hwmon_dev);
}
static const struct of_device_id gxp_fan_ctrl_of_match[] = {
{ .compatible = "hpe,gxp-fan-ctrl", },
{},
};
MODULE_DEVICE_TABLE(of, gxp_fan_ctrl_of_match);
static struct platform_driver gxp_fan_ctrl_driver = {
.probe = gxp_fan_ctrl_probe,
.driver = {
.name = "gxp-fan-ctrl",
.of_match_table = gxp_fan_ctrl_of_match,
},
};
module_platform_driver(gxp_fan_ctrl_driver);
MODULE_AUTHOR("Nick Hawkins <nick.hawkins@hpe.com>");
MODULE_DESCRIPTION("HPE GXP fan controller");
MODULE_LICENSE("GPL");