Power sensor driver might want to signal that the power
value is not usable. Add a new power fault attribute to
report such failures.
Signed-off-by: Armin Wolf <[email protected]>
---
Changes since v2:
- added patch
---
Documentation/ABI/testing/sysfs-class-hwmon | 9 +++++++++
drivers/hwmon/hwmon.c | 1 +
include/linux/hwmon.h | 2 ++
3 files changed, 12 insertions(+)
diff --git a/Documentation/ABI/testing/sysfs-class-hwmon b/Documentation/ABI/testing/sysfs-class-hwmon
index cfd0d0bab483..ed01d43d2491 100644
--- a/Documentation/ABI/testing/sysfs-class-hwmon
+++ b/Documentation/ABI/testing/sysfs-class-hwmon
@@ -882,6 +882,15 @@ Description:
RW
+What: /sys/class/hwmon/hwmonX/powerY_fault
+Description:
+ Reports a power sensor failure.
+
+ - 1: Failed
+ - 0: Ok
+
+ RO
+
What: /sys/class/hwmon/hwmonX/powerY_rated_min
Description:
Minimum rated power.
diff --git a/drivers/hwmon/hwmon.c b/drivers/hwmon/hwmon.c
index 3b259c425ab7..6150d64f5c4c 100644
--- a/drivers/hwmon/hwmon.c
+++ b/drivers/hwmon/hwmon.c
@@ -560,6 +560,7 @@ static const char * const hwmon_power_attr_templates[] = {
[hwmon_power_crit] = "power%d_crit",
[hwmon_power_label] = "power%d_label",
[hwmon_power_alarm] = "power%d_alarm",
+ [hwmon_power_fault] = "power%d_fault",
[hwmon_power_cap_alarm] = "power%d_cap_alarm",
[hwmon_power_min_alarm] = "power%d_min_alarm",
[hwmon_power_max_alarm] = "power%d_max_alarm",
diff --git a/include/linux/hwmon.h b/include/linux/hwmon.h
index edf96f249eb5..00122e565dbf 100644
--- a/include/linux/hwmon.h
+++ b/include/linux/hwmon.h
@@ -237,6 +237,7 @@ enum hwmon_power_attributes {
hwmon_power_max_alarm,
hwmon_power_lcrit_alarm,
hwmon_power_crit_alarm,
+ hwmon_power_fault,
hwmon_power_rated_min,
hwmon_power_rated_max,
};
@@ -270,6 +271,7 @@ enum hwmon_power_attributes {
#define HWMON_P_MAX_ALARM BIT(hwmon_power_max_alarm)
#define HWMON_P_LCRIT_ALARM BIT(hwmon_power_lcrit_alarm)
#define HWMON_P_CRIT_ALARM BIT(hwmon_power_crit_alarm)
+#define HWMON_P_FAULT BIT(hwmon_power_fault)
#define HWMON_P_RATED_MIN BIT(hwmon_power_rated_min)
#define HWMON_P_RATED_MAX BIT(hwmon_power_rated_max)
--
2.39.2
Currently, the driver does only support a custom sysfs
to allow userspace to read the fan speed.
Add support for the standard hwmon interface so users
can read the fan speed with standard tools like "sensors".
Compile-tested only.
Signed-off-by: Armin Wolf <[email protected]>
---
Changes since v2:
- add support for fanX_target and power attrs
Changes since v1:
- fix undefined reference error
- fix fan speed validation
- coding style fixes
- clarify that the changes are compile-tested only
- add hwmon maintainers to cc list
The changes will be tested by Mikael Lund Jepsen from Danelec and
should be merged only after those tests.
---
drivers/acpi/Makefile | 1 +
drivers/acpi/fan.h | 9 +++
drivers/acpi/fan_core.c | 4 ++
drivers/acpi/fan_hwmon.c | 148 +++++++++++++++++++++++++++++++++++++++
4 files changed, 162 insertions(+)
create mode 100644 drivers/acpi/fan_hwmon.c
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index 39ea5cfa8326..61ca4afe83dc 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -77,6 +77,7 @@ obj-$(CONFIG_ACPI_TINY_POWER_BUTTON) += tiny-power-button.o
obj-$(CONFIG_ACPI_FAN) += fan.o
fan-objs := fan_core.o
fan-objs += fan_attr.o
+fan-$(CONFIG_HWMON) += fan_hwmon.o
obj-$(CONFIG_ACPI_VIDEO) += video.o
obj-$(CONFIG_ACPI_TAD) += acpi_tad.o
diff --git a/drivers/acpi/fan.h b/drivers/acpi/fan.h
index f89d19c922dc..db25a3898af7 100644
--- a/drivers/acpi/fan.h
+++ b/drivers/acpi/fan.h
@@ -10,6 +10,8 @@
#ifndef _ACPI_FAN_H_
#define _ACPI_FAN_H_
+#include <linux/kconfig.h>
+
#define ACPI_FAN_DEVICE_IDS \
{"INT3404", }, /* Fan */ \
{"INTC1044", }, /* Fan for Tiger Lake generation */ \
@@ -57,4 +59,11 @@ struct acpi_fan {
int acpi_fan_get_fst(struct acpi_device *device, struct acpi_fan_fst *fst);
int acpi_fan_create_attributes(struct acpi_device *device);
void acpi_fan_delete_attributes(struct acpi_device *device);
+
+#if IS_REACHABLE(CONFIG_HWMON)
+int devm_acpi_fan_create_hwmon(struct acpi_device *device);
+#else
+static inline int devm_acpi_fan_create_hwmon(struct acpi_device *device) { return 0; };
+#endif
+
#endif
diff --git a/drivers/acpi/fan_core.c b/drivers/acpi/fan_core.c
index ff72e4ef8738..7cea4495f19b 100644
--- a/drivers/acpi/fan_core.c
+++ b/drivers/acpi/fan_core.c
@@ -336,6 +336,10 @@ static int acpi_fan_probe(struct platform_device *pdev)
if (result)
return result;
+ result = devm_acpi_fan_create_hwmon(device);
+ if (result)
+ return result;
+
result = acpi_fan_create_attributes(device);
if (result)
return result;
diff --git a/drivers/acpi/fan_hwmon.c b/drivers/acpi/fan_hwmon.c
new file mode 100644
index 000000000000..57216ba872db
--- /dev/null
+++ b/drivers/acpi/fan_hwmon.c
@@ -0,0 +1,148 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * fan_hwmon.c - hwmon interface for the ACPI Fan driver
+ *
+ * Copyright (C) 2024 Armin Wolf <[email protected]>
+ */
+
+#include <linux/acpi.h>
+#include <linux/hwmon.h>
+#include <linux/limits.h>
+#include <linux/units.h>
+
+#include "fan.h"
+
+/* Returned when the ACPI fan does not support speed reporting */
+#define FAN_SPEED_UNAVAILABLE 0xffffffff
+#define FAN_POWER_UNAVAILABLE 0xffffffff
+
+static struct acpi_fan_fps *acpi_fan_get_current_fps(struct acpi_fan *fan, u64 control)
+{
+ int i;
+
+ for (i = 0; i < fan->fps_count; i++) {
+ if (fan->fps[i].control == control)
+ return &fan->fps[i];
+ }
+
+ return NULL;
+}
+
+static umode_t acpi_fan_is_visible(const void *drvdata, enum hwmon_sensor_types type, u32 attr,
+ int channel)
+{
+ return 0444;
+}
+
+static int acpi_fan_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel,
+ long *val)
+{
+ struct acpi_device *adev = dev_get_drvdata(dev);
+ struct acpi_fan *fan = acpi_driver_data(adev);
+ struct acpi_fan_fps *fps;
+ struct acpi_fan_fst fst;
+ int ret;
+
+ ret = acpi_fan_get_fst(adev, &fst);
+ if (ret < 0)
+ return ret;
+
+ switch (type) {
+ case hwmon_fan:
+ switch (attr) {
+ case hwmon_fan_input:
+ if (fst.speed == FAN_SPEED_UNAVAILABLE)
+ return -ENODATA;
+
+ if (fst.speed > LONG_MAX)
+ return -EOVERFLOW;
+
+ *val = fst.speed;
+ return 0;
+ case hwmon_fan_target:
+ fps = acpi_fan_get_current_fps(fan, fst.control);
+ if (!fps)
+ return -ENODATA;
+
+ *val = fps->speed;
+ return 0;
+ case hwmon_fan_fault:
+ *val = (fst.speed == FAN_SPEED_UNAVAILABLE);
+ return 0;
+ default:
+ break;
+ }
+ break;
+ case hwmon_power:
+ fps = acpi_fan_get_current_fps(fan, fst.control);
+ if (!fps)
+ return -ENODATA;
+
+ switch (attr) {
+ case hwmon_power_input:
+ if (fps->power == FAN_POWER_UNAVAILABLE)
+ return -ENODATA;
+
+ if (fps->power > LONG_MAX / MICROWATT_PER_MILLIWATT)
+ return -EOVERFLOW;
+
+ *val = fps->power * MICROWATT_PER_MILLIWATT;
+ return 0;
+ case hwmon_power_fault:
+ *val = (fps->power == FAN_POWER_UNAVAILABLE);
+ return 0;
+ default:
+ break;
+ }
+ break;
+ default:
+ break;
+ }
+
+ return -EOPNOTSUPP;
+}
+
+static const struct hwmon_ops acpi_fan_ops = {
+ .is_visible = acpi_fan_is_visible,
+ .read = acpi_fan_read,
+};
+
+static const struct hwmon_channel_info * const acpi_fan_info[] = {
+ HWMON_CHANNEL_INFO(fan, HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_FAULT),
+ HWMON_CHANNEL_INFO(power, HWMON_P_INPUT | HWMON_P_FAULT),
+ NULL
+};
+
+static const struct hwmon_chip_info acpi_fan_chip_info = {
+ .ops = &acpi_fan_ops,
+ .info = acpi_fan_info,
+};
+
+static const struct hwmon_channel_info * const acpi_fan_fine_grain_info[] = {
+ HWMON_CHANNEL_INFO(fan, HWMON_F_INPUT | HWMON_F_FAULT),
+ NULL
+};
+
+static const struct hwmon_chip_info acpi_fan_fine_grain_chip_info = {
+ .ops = &acpi_fan_ops,
+ .info = acpi_fan_fine_grain_info,
+};
+
+int devm_acpi_fan_create_hwmon(struct acpi_device *device)
+{
+ struct acpi_fan *fan = acpi_driver_data(device);
+ const struct hwmon_chip_info *info;
+ struct device *hdev;
+
+ /* When in fine grain control mode, not every fan control value
+ * has an associated fan performance state.
+ */
+ if (fan->fif.fine_grain_ctrl)
+ info = &acpi_fan_fine_grain_chip_info;
+ else
+ info = &acpi_fan_chip_info;
+
+ hdev = devm_hwmon_device_register_with_info(&device->dev, "acpi_fan", device, info, NULL);
+
+ return PTR_ERR_OR_ZERO(hdev);
+}
--
2.39.2
On Fri, Apr 12, 2024 at 06:08:57PM +0200, Armin Wolf wrote:
> Currently, the driver does only support a custom sysfs
> to allow userspace to read the fan speed.
> Add support for the standard hwmon interface so users
> can read the fan speed with standard tools like "sensors".
>
> Compile-tested only.
>
> Signed-off-by: Armin Wolf <[email protected]>
> ---
> Changes since v2:
> - add support for fanX_target and power attrs
>
> Changes since v1:
> - fix undefined reference error
> - fix fan speed validation
> - coding style fixes
> - clarify that the changes are compile-tested only
> - add hwmon maintainers to cc list
>
> The changes will be tested by Mikael Lund Jepsen from Danelec and
> should be merged only after those tests.
> ---
> drivers/acpi/Makefile | 1 +
> drivers/acpi/fan.h | 9 +++
> drivers/acpi/fan_core.c | 4 ++
> drivers/acpi/fan_hwmon.c | 148 +++++++++++++++++++++++++++++++++++++++
> 4 files changed, 162 insertions(+)
> create mode 100644 drivers/acpi/fan_hwmon.c
>
> diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
> index 39ea5cfa8326..61ca4afe83dc 100644
> --- a/drivers/acpi/Makefile
> +++ b/drivers/acpi/Makefile
> @@ -77,6 +77,7 @@ obj-$(CONFIG_ACPI_TINY_POWER_BUTTON) += tiny-power-button.o
> obj-$(CONFIG_ACPI_FAN) += fan.o
> fan-objs := fan_core.o
> fan-objs += fan_attr.o
> +fan-$(CONFIG_HWMON) += fan_hwmon.o
>
> obj-$(CONFIG_ACPI_VIDEO) += video.o
> obj-$(CONFIG_ACPI_TAD) += acpi_tad.o
> diff --git a/drivers/acpi/fan.h b/drivers/acpi/fan.h
> index f89d19c922dc..db25a3898af7 100644
> --- a/drivers/acpi/fan.h
> +++ b/drivers/acpi/fan.h
> @@ -10,6 +10,8 @@
> #ifndef _ACPI_FAN_H_
> #define _ACPI_FAN_H_
>
> +#include <linux/kconfig.h>
> +
> #define ACPI_FAN_DEVICE_IDS \
> {"INT3404", }, /* Fan */ \
> {"INTC1044", }, /* Fan for Tiger Lake generation */ \
> @@ -57,4 +59,11 @@ struct acpi_fan {
> int acpi_fan_get_fst(struct acpi_device *device, struct acpi_fan_fst *fst);
> int acpi_fan_create_attributes(struct acpi_device *device);
> void acpi_fan_delete_attributes(struct acpi_device *device);
> +
> +#if IS_REACHABLE(CONFIG_HWMON)
> +int devm_acpi_fan_create_hwmon(struct acpi_device *device);
> +#else
> +static inline int devm_acpi_fan_create_hwmon(struct acpi_device *device) { return 0; };
> +#endif
> +
> #endif
> diff --git a/drivers/acpi/fan_core.c b/drivers/acpi/fan_core.c
> index ff72e4ef8738..7cea4495f19b 100644
> --- a/drivers/acpi/fan_core.c
> +++ b/drivers/acpi/fan_core.c
> @@ -336,6 +336,10 @@ static int acpi_fan_probe(struct platform_device *pdev)
> if (result)
> return result;
>
> + result = devm_acpi_fan_create_hwmon(device);
> + if (result)
> + return result;
> +
> result = acpi_fan_create_attributes(device);
> if (result)
> return result;
> diff --git a/drivers/acpi/fan_hwmon.c b/drivers/acpi/fan_hwmon.c
> new file mode 100644
> index 000000000000..57216ba872db
> --- /dev/null
> +++ b/drivers/acpi/fan_hwmon.c
> @@ -0,0 +1,148 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * fan_hwmon.c - hwmon interface for the ACPI Fan driver
> + *
> + * Copyright (C) 2024 Armin Wolf <[email protected]>
> + */
> +
> +#include <linux/acpi.h>
> +#include <linux/hwmon.h>
> +#include <linux/limits.h>
> +#include <linux/units.h>
> +
> +#include "fan.h"
> +
> +/* Returned when the ACPI fan does not support speed reporting */
> +#define FAN_SPEED_UNAVAILABLE 0xffffffff
> +#define FAN_POWER_UNAVAILABLE 0xffffffff
> +
> +static struct acpi_fan_fps *acpi_fan_get_current_fps(struct acpi_fan *fan, u64 control)
> +{
> + int i;
> +
> + for (i = 0; i < fan->fps_count; i++) {
> + if (fan->fps[i].control == control)
> + return &fan->fps[i];
> + }
> +
> + return NULL;
> +}
> +
> +static umode_t acpi_fan_is_visible(const void *drvdata, enum hwmon_sensor_types type, u32 attr,
> + int channel)
> +{
> + return 0444;
> +}
> +
> +static int acpi_fan_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel,
> + long *val)
> +{
> + struct acpi_device *adev = dev_get_drvdata(dev);
> + struct acpi_fan *fan = acpi_driver_data(adev);
> + struct acpi_fan_fps *fps;
> + struct acpi_fan_fst fst;
> + int ret;
> +
> + ret = acpi_fan_get_fst(adev, &fst);
> + if (ret < 0)
> + return ret;
> +
> + switch (type) {
> + case hwmon_fan:
> + switch (attr) {
> + case hwmon_fan_input:
> + if (fst.speed == FAN_SPEED_UNAVAILABLE)
> + return -ENODATA;
> +
> + if (fst.speed > LONG_MAX)
> + return -EOVERFLOW;
> +
> + *val = fst.speed;
> + return 0;
> + case hwmon_fan_target:
> + fps = acpi_fan_get_current_fps(fan, fst.control);
> + if (!fps)
> + return -ENODATA;
> +
> + *val = fps->speed;
> + return 0;
> + case hwmon_fan_fault:
> + *val = (fst.speed == FAN_SPEED_UNAVAILABLE);
Is it documented that this is indeed a fault (broken fan) ?
> + return 0;
> + default:
> + break;
> + }
> + break;
> + case hwmon_power:
> + fps = acpi_fan_get_current_fps(fan, fst.control);
> + if (!fps)
> + return -ENODATA;
> +
> + switch (attr) {
> + case hwmon_power_input:
> + if (fps->power == FAN_POWER_UNAVAILABLE)
> + return -ENODATA;
> +
> + if (fps->power > LONG_MAX / MICROWATT_PER_MILLIWATT)
> + return -EOVERFLOW;
> +
> + *val = fps->power * MICROWATT_PER_MILLIWATT;
> + return 0;
> + case hwmon_power_fault:
> + *val = (fps->power == FAN_POWER_UNAVAILABLE);
Is it documented that this is indeed a power supply failure ?
What if the value is simply not reported ? "UNAVAILABLE" is not
commonly associated with a "fault".
Guenter
> + return 0;
> + default:
> + break;
> + }
> + break;
> + default:
> + break;
> + }
> +
> + return -EOPNOTSUPP;
> +}
> +
> +static const struct hwmon_ops acpi_fan_ops = {
> + .is_visible = acpi_fan_is_visible,
> + .read = acpi_fan_read,
> +};
> +
> +static const struct hwmon_channel_info * const acpi_fan_info[] = {
> + HWMON_CHANNEL_INFO(fan, HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_FAULT),
> + HWMON_CHANNEL_INFO(power, HWMON_P_INPUT | HWMON_P_FAULT),
> + NULL
> +};
> +
> +static const struct hwmon_chip_info acpi_fan_chip_info = {
> + .ops = &acpi_fan_ops,
> + .info = acpi_fan_info,
> +};
> +
> +static const struct hwmon_channel_info * const acpi_fan_fine_grain_info[] = {
> + HWMON_CHANNEL_INFO(fan, HWMON_F_INPUT | HWMON_F_FAULT),
> + NULL
> +};
> +
> +static const struct hwmon_chip_info acpi_fan_fine_grain_chip_info = {
> + .ops = &acpi_fan_ops,
> + .info = acpi_fan_fine_grain_info,
> +};
> +
> +int devm_acpi_fan_create_hwmon(struct acpi_device *device)
> +{
> + struct acpi_fan *fan = acpi_driver_data(device);
> + const struct hwmon_chip_info *info;
> + struct device *hdev;
> +
> + /* When in fine grain control mode, not every fan control value
> + * has an associated fan performance state.
> + */
> + if (fan->fif.fine_grain_ctrl)
> + info = &acpi_fan_fine_grain_chip_info;
> + else
> + info = &acpi_fan_chip_info;
> +
> + hdev = devm_hwmon_device_register_with_info(&device->dev, "acpi_fan", device, info, NULL);
> +
> + return PTR_ERR_OR_ZERO(hdev);
> +}
> --
> 2.39.2
>
Am 12.04.24 um 18:41 schrieb Guenter Roeck:
> On Fri, Apr 12, 2024 at 06:08:57PM +0200, Armin Wolf wrote:
>> Currently, the driver does only support a custom sysfs
>> to allow userspace to read the fan speed.
>> Add support for the standard hwmon interface so users
>> can read the fan speed with standard tools like "sensors".
>>
>> Compile-tested only.
>>
>> Signed-off-by: Armin Wolf <[email protected]>
>> ---
>> Changes since v2:
>> - add support for fanX_target and power attrs
>>
>> Changes since v1:
>> - fix undefined reference error
>> - fix fan speed validation
>> - coding style fixes
>> - clarify that the changes are compile-tested only
>> - add hwmon maintainers to cc list
>>
>> The changes will be tested by Mikael Lund Jepsen from Danelec and
>> should be merged only after those tests.
>> ---
>> drivers/acpi/Makefile | 1 +
>> drivers/acpi/fan.h | 9 +++
>> drivers/acpi/fan_core.c | 4 ++
>> drivers/acpi/fan_hwmon.c | 148 +++++++++++++++++++++++++++++++++++++++
>> 4 files changed, 162 insertions(+)
>> create mode 100644 drivers/acpi/fan_hwmon.c
>>
>> diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
>> index 39ea5cfa8326..61ca4afe83dc 100644
>> --- a/drivers/acpi/Makefile
>> +++ b/drivers/acpi/Makefile
>> @@ -77,6 +77,7 @@ obj-$(CONFIG_ACPI_TINY_POWER_BUTTON) += tiny-power-button.o
>> obj-$(CONFIG_ACPI_FAN) += fan.o
>> fan-objs := fan_core.o
>> fan-objs += fan_attr.o
>> +fan-$(CONFIG_HWMON) += fan_hwmon.o
>>
>> obj-$(CONFIG_ACPI_VIDEO) += video.o
>> obj-$(CONFIG_ACPI_TAD) += acpi_tad.o
>> diff --git a/drivers/acpi/fan.h b/drivers/acpi/fan.h
>> index f89d19c922dc..db25a3898af7 100644
>> --- a/drivers/acpi/fan.h
>> +++ b/drivers/acpi/fan.h
>> @@ -10,6 +10,8 @@
>> #ifndef _ACPI_FAN_H_
>> #define _ACPI_FAN_H_
>>
>> +#include <linux/kconfig.h>
>> +
>> #define ACPI_FAN_DEVICE_IDS \
>> {"INT3404", }, /* Fan */ \
>> {"INTC1044", }, /* Fan for Tiger Lake generation */ \
>> @@ -57,4 +59,11 @@ struct acpi_fan {
>> int acpi_fan_get_fst(struct acpi_device *device, struct acpi_fan_fst *fst);
>> int acpi_fan_create_attributes(struct acpi_device *device);
>> void acpi_fan_delete_attributes(struct acpi_device *device);
>> +
>> +#if IS_REACHABLE(CONFIG_HWMON)
>> +int devm_acpi_fan_create_hwmon(struct acpi_device *device);
>> +#else
>> +static inline int devm_acpi_fan_create_hwmon(struct acpi_device *device) { return 0; };
>> +#endif
>> +
>> #endif
>> diff --git a/drivers/acpi/fan_core.c b/drivers/acpi/fan_core.c
>> index ff72e4ef8738..7cea4495f19b 100644
>> --- a/drivers/acpi/fan_core.c
>> +++ b/drivers/acpi/fan_core.c
>> @@ -336,6 +336,10 @@ static int acpi_fan_probe(struct platform_device *pdev)
>> if (result)
>> return result;
>>
>> + result = devm_acpi_fan_create_hwmon(device);
>> + if (result)
>> + return result;
>> +
>> result = acpi_fan_create_attributes(device);
>> if (result)
>> return result;
>> diff --git a/drivers/acpi/fan_hwmon.c b/drivers/acpi/fan_hwmon.c
>> new file mode 100644
>> index 000000000000..57216ba872db
>> --- /dev/null
>> +++ b/drivers/acpi/fan_hwmon.c
>> @@ -0,0 +1,148 @@
>> +// SPDX-License-Identifier: GPL-2.0-or-later
>> +/*
>> + * fan_hwmon.c - hwmon interface for the ACPI Fan driver
>> + *
>> + * Copyright (C) 2024 Armin Wolf <[email protected]>
>> + */
>> +
>> +#include <linux/acpi.h>
>> +#include <linux/hwmon.h>
>> +#include <linux/limits.h>
>> +#include <linux/units.h>
>> +
>> +#include "fan.h"
>> +
>> +/* Returned when the ACPI fan does not support speed reporting */
>> +#define FAN_SPEED_UNAVAILABLE 0xffffffff
>> +#define FAN_POWER_UNAVAILABLE 0xffffffff
>> +
>> +static struct acpi_fan_fps *acpi_fan_get_current_fps(struct acpi_fan *fan, u64 control)
>> +{
>> + int i;
>> +
>> + for (i = 0; i < fan->fps_count; i++) {
>> + if (fan->fps[i].control == control)
>> + return &fan->fps[i];
>> + }
>> +
>> + return NULL;
>> +}
>> +
>> +static umode_t acpi_fan_is_visible(const void *drvdata, enum hwmon_sensor_types type, u32 attr,
>> + int channel)
>> +{
>> + return 0444;
>> +}
>> +
>> +static int acpi_fan_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel,
>> + long *val)
>> +{
>> + struct acpi_device *adev = dev_get_drvdata(dev);
>> + struct acpi_fan *fan = acpi_driver_data(adev);
>> + struct acpi_fan_fps *fps;
>> + struct acpi_fan_fst fst;
>> + int ret;
>> +
>> + ret = acpi_fan_get_fst(adev, &fst);
>> + if (ret < 0)
>> + return ret;
>> +
>> + switch (type) {
>> + case hwmon_fan:
>> + switch (attr) {
>> + case hwmon_fan_input:
>> + if (fst.speed == FAN_SPEED_UNAVAILABLE)
>> + return -ENODATA;
>> +
>> + if (fst.speed > LONG_MAX)
>> + return -EOVERFLOW;
>> +
>> + *val = fst.speed;
>> + return 0;
>> + case hwmon_fan_target:
>> + fps = acpi_fan_get_current_fps(fan, fst.control);
>> + if (!fps)
>> + return -ENODATA;
>> +
>> + *val = fps->speed;
>> + return 0;
>> + case hwmon_fan_fault:
>> + *val = (fst.speed == FAN_SPEED_UNAVAILABLE);
> Is it documented that this is indeed a fault (broken fan) ?
>
Hi,
it actually means that the fan does not support speed reporting.
>> + return 0;
>> + default:
>> + break;
>> + }
>> + break;
>> + case hwmon_power:
>> + fps = acpi_fan_get_current_fps(fan, fst.control);
>> + if (!fps)
>> + return -ENODATA;
>> +
>> + switch (attr) {
>> + case hwmon_power_input:
>> + if (fps->power == FAN_POWER_UNAVAILABLE)
>> + return -ENODATA;
>> +
>> + if (fps->power > LONG_MAX / MICROWATT_PER_MILLIWATT)
>> + return -EOVERFLOW;
>> +
>> + *val = fps->power * MICROWATT_PER_MILLIWATT;
>> + return 0;
>> + case hwmon_power_fault:
>> + *val = (fps->power == FAN_POWER_UNAVAILABLE);
> Is it documented that this is indeed a power supply failure ?
> What if the value is simply not reported ? "UNAVAILABLE" is not
> commonly associated with a "fault".
>
> Guenter
>
FAN_POWER_UNAVAILABLE signals that the power value is not supported.
Would it be more suitable to drop the fault attributes and just return -ENODATA in such a case?
Thanks,
Armin Wolf
>> + return 0;
>> + default:
>> + break;
>> + }
>> + break;
>> + default:
>> + break;
>> + }
>> +
>> + return -EOPNOTSUPP;
>> +}
>> +
>> +static const struct hwmon_ops acpi_fan_ops = {
>> + .is_visible = acpi_fan_is_visible,
>> + .read = acpi_fan_read,
>> +};
>> +
>> +static const struct hwmon_channel_info * const acpi_fan_info[] = {
>> + HWMON_CHANNEL_INFO(fan, HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_FAULT),
>> + HWMON_CHANNEL_INFO(power, HWMON_P_INPUT | HWMON_P_FAULT),
>> + NULL
>> +};
>> +
>> +static const struct hwmon_chip_info acpi_fan_chip_info = {
>> + .ops = &acpi_fan_ops,
>> + .info = acpi_fan_info,
>> +};
>> +
>> +static const struct hwmon_channel_info * const acpi_fan_fine_grain_info[] = {
>> + HWMON_CHANNEL_INFO(fan, HWMON_F_INPUT | HWMON_F_FAULT),
>> + NULL
>> +};
>> +
>> +static const struct hwmon_chip_info acpi_fan_fine_grain_chip_info = {
>> + .ops = &acpi_fan_ops,
>> + .info = acpi_fan_fine_grain_info,
>> +};
>> +
>> +int devm_acpi_fan_create_hwmon(struct acpi_device *device)
>> +{
>> + struct acpi_fan *fan = acpi_driver_data(device);
>> + const struct hwmon_chip_info *info;
>> + struct device *hdev;
>> +
>> + /* When in fine grain control mode, not every fan control value
>> + * has an associated fan performance state.
>> + */
>> + if (fan->fif.fine_grain_ctrl)
>> + info = &acpi_fan_fine_grain_chip_info;
>> + else
>> + info = &acpi_fan_chip_info;
>> +
>> + hdev = devm_hwmon_device_register_with_info(&device->dev, "acpi_fan", device, info, NULL);
>> +
>> + return PTR_ERR_OR_ZERO(hdev);
>> +}
>> --
>> 2.39.2
>>
On Fri, Apr 12, 2024 at 10:27:56PM +0200, Armin Wolf wrote:
> > > + case hwmon_fan_fault:
> > > + *val = (fst.speed == FAN_SPEED_UNAVAILABLE);
> > Is it documented that this is indeed a fault (broken fan) ?
> >
> Hi,
>
> it actually means that the fan does not support speed reporting.
>
> > > + return 0;
> > > + default:
> > > + break;
> > > + }
> > > + break;
> > > + case hwmon_power:
> > > + fps = acpi_fan_get_current_fps(fan, fst.control);
> > > + if (!fps)
> > > + return -ENODATA;
> > > +
> > > + switch (attr) {
> > > + case hwmon_power_input:
> > > + if (fps->power == FAN_POWER_UNAVAILABLE)
> > > + return -ENODATA;
> > > +
> > > + if (fps->power > LONG_MAX / MICROWATT_PER_MILLIWATT)
> > > + return -EOVERFLOW;
> > > +
> > > + *val = fps->power * MICROWATT_PER_MILLIWATT;
> > > + return 0;
> > > + case hwmon_power_fault:
> > > + *val = (fps->power == FAN_POWER_UNAVAILABLE);
> > Is it documented that this is indeed a power supply failure ?
> > What if the value is simply not reported ? "UNAVAILABLE" is not
> > commonly associated with a "fault".
> >
> > Guenter
> >
> FAN_POWER_UNAVAILABLE signals that the power value is not supported.
> Would it be more suitable to drop the fault attributes and just return -ENODATA in such a case?
>
There should be no fault attributes unless a real fault
is reported, and if power reporting is not supported the
hwmon_power_input attribute should not even be created.
The same really applies to the fan speed atribute: If reading
the fan speed is not supported, the attribute should not even
exist.
Guenter
Am 12.04.24 um 23:01 schrieb Guenter Roeck:
> On Fri, Apr 12, 2024 at 10:27:56PM +0200, Armin Wolf wrote:
>>>> + case hwmon_fan_fault:
>>>> + *val = (fst.speed == FAN_SPEED_UNAVAILABLE);
>>> Is it documented that this is indeed a fault (broken fan) ?
>>>
>> Hi,
>>
>> it actually means that the fan does not support speed reporting.
>>
>>>> + return 0;
>>>> + default:
>>>> + break;
>>>> + }
>>>> + break;
>>>> + case hwmon_power:
>>>> + fps = acpi_fan_get_current_fps(fan, fst.control);
>>>> + if (!fps)
>>>> + return -ENODATA;
>>>> +
>>>> + switch (attr) {
>>>> + case hwmon_power_input:
>>>> + if (fps->power == FAN_POWER_UNAVAILABLE)
>>>> + return -ENODATA;
>>>> +
>>>> + if (fps->power > LONG_MAX / MICROWATT_PER_MILLIWATT)
>>>> + return -EOVERFLOW;
>>>> +
>>>> + *val = fps->power * MICROWATT_PER_MILLIWATT;
>>>> + return 0;
>>>> + case hwmon_power_fault:
>>>> + *val = (fps->power == FAN_POWER_UNAVAILABLE);
>>> Is it documented that this is indeed a power supply failure ?
>>> What if the value is simply not reported ? "UNAVAILABLE" is not
>>> commonly associated with a "fault".
>>>
>>> Guenter
>>>
>> FAN_POWER_UNAVAILABLE signals that the power value is not supported.
>> Would it be more suitable to drop the fault attributes and just return -ENODATA in such a case?
>>
> There should be no fault attributes unless a real fault
> is reported, and if power reporting is not supported the
> hwmon_power_input attribute should not even be created.
>
> The same really applies to the fan speed atribute: If reading
> the fan speed is not supported, the attribute should not even
> exist.
>
> Guenter
>
I see, however it seems that some ACPI implementations also return a fan speed of 0xffffffff
to signal an error, so we cannot use this value to check if the BIOS supports fan speed
reporting.
I will send a v4 patch witch will drop the fault attributes. When encountering a fan speed
of 0xffffffff, returning -ENODATA should be ok i think.
Thanks,
Armin Wolf