drivers/platform/x86/hp/hp-wmi.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+)
On the HP ENVY x360 Convertible 13-bd0xxx (board 8824), the WMI
interfaces for reading fan speed (HPWMI_FAN_SPEED_GET_QUERY) return
zero-filled buffers regardless of the actual fan speed.
This results in the hp_wmi driver exposing `fan1_input` and `fan2_input`
nodes through hwmon that permanently report "0 RPM", which is misleading
and interferes with userspace sensor monitoring tools.
Add a DMI quirk to disable exposing the hwmon fan nodes on this specific
board.
Signed-off-by: Bani Brata <banibrata2007@gmail.com>
---
drivers/platform/x86/hp/hp-wmi.c | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff --git a/drivers/platform/x86/hp/hp-wmi.c b/drivers/platform/x86/hp/hp-wmi.c
index XXXXXXX..XXXXXXX 100644
--- a/drivers/platform/x86/hp/hp-wmi.c
+++ b/drivers/platform/x86/hp/hp-wmi.c
@@ -192,6 +192,18 @@ static const struct dmi_system_id hp_wmi_rfkill_dmi_table[] __initconst = {
};
static bool is_victus_s_board;
+static bool is_envy_x360_8824_board;
+
+static const struct dmi_system_id hp_envy_x360_8824_boards[] __initconst = {
+ {
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "HP"),
+ DMI_MATCH(DMI_PRODUCT_NAME, "HP ENVY x360 Convertible 13-bd0xxx"),
+ DMI_MATCH(DMI_BOARD_NAME, "8824"),
+ },
+ },
+ {},
+};
enum hp_wmi_radio {
HPWMI_WIFI = 0x0,
@@ -2166,6 +2178,8 @@ static umode_t hp_wmi_hwmon_is_visible(const void *data,
case hwmon_pwm:
return 0644;
case hwmon_fan:
+ if (is_envy_x360_8824_board)
+ return 0;
if (is_victus_s_thermal_profile()) {
if (hp_wmi_get_fan_speed_victus_s(channel) >= 0)
return 0444;
@@ -2188,6 +2202,8 @@ static int hp_wmi_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
switch (type) {
case hwmon_fan:
+ if (is_envy_x360_8824_board)
+ return -EOPNOTSUPP;
if (is_victus_s_thermal_profile())
ret = hp_wmi_get_fan_speed_victus_s(channel);
else
@@ -2281,6 +2297,8 @@ static int __init hp_wmi_bios_setup(struct platform_device *device)
{
const struct dmi_system_id *id;
+ is_envy_x360_8824_board = dmi_first_match(hp_envy_x360_8824_boards);
+
/*
* Currently only victus_s devices use the
* active_thermal_profile_params
--
2.48.1On Sun, 29 Mar 2026, Bani Brata wrote:
> On the HP ENVY x360 Convertible 13-bd0xxx (board 8824), the WMI
> interfaces for reading fan speed (HPWMI_FAN_SPEED_GET_QUERY) return
> zero-filled buffers regardless of the actual fan speed.
>
> This results in the hp_wmi driver exposing `fan1_input` and `fan2_input`
> nodes through hwmon that permanently report "0 RPM", which is misleading
> and interferes with userspace sensor monitoring tools.
>
> Add a DMI quirk to disable exposing the hwmon fan nodes on this specific
> board.
>
> Signed-off-by: Bani Brata <banibrata2007@gmail.com>
> ---
> drivers/platform/x86/hp/hp-wmi.c | 18 ++++++++++++++++++
> 1 file changed, 18 insertions(+)
>
> diff --git a/drivers/platform/x86/hp/hp-wmi.c b/drivers/platform/x86/hp/hp-wmi.c
> index XXXXXXX..XXXXXXX 100644
> --- a/drivers/platform/x86/hp/hp-wmi.c
> +++ b/drivers/platform/x86/hp/hp-wmi.c
> @@ -192,6 +192,18 @@ static const struct dmi_system_id hp_wmi_rfkill_dmi_table[] __initconst = {
> };
>
> static bool is_victus_s_board;
> +static bool is_envy_x360_8824_board;
> +
> +static const struct dmi_system_id hp_envy_x360_8824_boards[] __initconst = {
> + {
> + .matches = {
> + DMI_MATCH(DMI_SYS_VENDOR, "HP"),
> + DMI_MATCH(DMI_PRODUCT_NAME, "HP ENVY x360 Convertible 13-bd0xxx"),
> + DMI_MATCH(DMI_BOARD_NAME, "8824"),
> + },
> + },
> + {},
> +};
>
> enum hp_wmi_radio {
> HPWMI_WIFI = 0x0,
> @@ -2166,6 +2178,8 @@ static umode_t hp_wmi_hwmon_is_visible(const void *data,
> case hwmon_pwm:
> return 0644;
> case hwmon_fan:
> + if (is_envy_x360_8824_board)
> + return 0;
> if (is_victus_s_thermal_profile()) {
> if (hp_wmi_get_fan_speed_victus_s(channel) >= 0)
> return 0444;
> @@ -2188,6 +2202,8 @@ static int hp_wmi_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
>
> switch (type) {
> case hwmon_fan:
> + if (is_envy_x360_8824_board)
> + return -EOPNOTSUPP;
> if (is_victus_s_thermal_profile())
> ret = hp_wmi_get_fan_speed_victus_s(channel);
> else
> @@ -2281,6 +2297,8 @@ static int __init hp_wmi_bios_setup(struct platform_device *device)
> {
> const struct dmi_system_id *id;
>
> + is_envy_x360_8824_board = dmi_first_match(hp_envy_x360_8824_boards);
> +
> /*
> * Currently only victus_s devices use the
> * active_thermal_profile_params
So does this mean we can't get fan speeds at all with this device?
(This approach is written very specific to a model and should be
generalized if there really isn't any way to get the speeds.)
I've Krishna Chomal who might have better ideas than me.
--
i.
On the HP ENVY x360 Convertible 13-bd0xxx (board 8824), standard WMI
methods for fan speed control and RPM reporting do not function.
However, the DSDT exposes ACPI methods (\_SB.PC00.LPCB.EC0.FANG and FANW)
that allow reading and writing an 8-bit PWM level (0-255) to the EC.
This patch maps these ACPI methods to standard hwmon `pwm1` and
`pwm1_enable` nodes, allowing userspace tools to successfully control
the fan speed.
Signed-off-by: Bani Brata <banibrata2007@gmail.com>
---
drivers/platform/x86/hp/hp-wmi.c | 155 ++++++++++++++++++++++++++++++-
1 file changed, 155 insertions(+)
diff --git a/drivers/platform/x86/hp/hp-wmi.c b/drivers/platform/x86/hp/hp-wmi.c
index XXXXXXX..XXXXXXX 100644
--- a/drivers/platform/x86/hp/hp-wmi.c
+++ b/drivers/platform/x86/hp/hp-wmi.c
@@ -48,6 +48,14 @@
#define HP_FAN_SPEED_AUTOMATIC 0x00
#define HP_POWER_LIMIT_DEFAULT 0x00
#define HP_POWER_LIMIT_NO_CHANGE 0xFF
+#define HP_ENVY_8824_ACPI_FANG "\\_SB.PC00.LPCB.EC0.FANG"
+#define HP_ENVY_8824_ACPI_FANW "\\_SB.PC00.LPCB.EC0.FANW"
+#define HP_ENVY_8824_FAN_VALUE_ARG 33026ULL
+#define HP_ENVY_8824_FAN_PRIME_ARG 33030ULL
+#define HP_ENVY_8824_FAN_PRIME_MANUAL 0xFFULL
+#define HP_ENVY_8824_FAN_PRIME_AUTO 0x8ULL
+#define HP_ENVY_8824_PWM_MODE_MANUAL 1
+#define HP_ENVY_8824_PWM_MODE_AUTO 2
#define ACPI_AC_CLASS "ac_adapter"
@@ -193,6 +201,8 @@ static const struct dmi_system_id hp_wmi_rfkill_dmi_table[] __initconst = {
static bool is_victus_s_board;
static bool is_envy_x360_8824_board;
+static DEFINE_MUTEX(hp_envy_x360_8824_fan_lock);
+static int hp_envy_x360_8824_pwm_mode = HP_ENVY_8824_PWM_MODE_AUTO;
static const struct dmi_system_id hp_envy_x360_8824_boards[] __initconst = {
{
@@ -518,6 +528,120 @@ static int hp_wmi_get_fan_speed_victus_s(int fan)
return ret;
}
+static int hp_envy_x360_8824_acpi_eval(const char *path,
+ const unsigned long long *args,
+ size_t arg_count,
+ unsigned long long *value)
+{
+ struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
+ union acpi_object params[2] = { };
+ struct acpi_object_list input = { .count = arg_count, .pointer = params };
+ union acpi_object *obj;
+ acpi_status status;
+ size_t i;
+
+ for (i = 0; i < arg_count; i++) {
+ params[i].type = ACPI_TYPE_INTEGER;
+ params[i].integer.value = args[i];
+ }
+
+ status = acpi_evaluate_object(NULL, (acpi_string)path,
+ arg_count ? &input : NULL, &output);
+ if (ACPI_FAILURE(status))
+ return -EIO;
+
+ obj = output.pointer;
+ if (!obj)
+ return -ENODATA;
+
+ if (obj->type != ACPI_TYPE_INTEGER) {
+ kfree(obj);
+ return -EINVAL;
+ }
+
+ *value = obj->integer.value;
+ kfree(obj);
+
+ return 0;
+}
+
+static int hp_envy_x360_8824_get_pwm_locked(void)
+{
+ unsigned long long args[] = { HP_ENVY_8824_FAN_VALUE_ARG };
+ unsigned long long value;
+ int ret;
+
+ ret = hp_envy_x360_8824_acpi_eval(HP_ENVY_8824_ACPI_FANG, args,
+ ARRAY_SIZE(args), &value);
+ if (ret)
+ return ret;
+ if (value > U8_MAX)
+ return -EINVAL;
+
+ return value;
+}
+
+static int hp_envy_x360_8824_set_pwm_locked(u8 pwm)
+{
+ unsigned long long args[] = {
+ HP_ENVY_8824_FAN_PRIME_ARG,
+ HP_ENVY_8824_FAN_PRIME_MANUAL,
+ };
+ unsigned long long value;
+ int ret;
+
+ ret = hp_envy_x360_8824_acpi_eval(HP_ENVY_8824_ACPI_FANW, args,
+ ARRAY_SIZE(args), &value);
+ if (ret)
+ return ret;
+
+ args[0] = HP_ENVY_8824_FAN_VALUE_ARG;
+ args[1] = pwm;
+ ret = hp_envy_x360_8824_acpi_eval(HP_ENVY_8824_ACPI_FANW, args,
+ ARRAY_SIZE(args), &value);
+ if (ret)
+ return ret;
+
+ hp_envy_x360_8824_pwm_mode = HP_ENVY_8824_PWM_MODE_MANUAL;
+ return 0;
+}
+
+static int hp_envy_x360_8824_set_auto_locked(void)
+{
+ unsigned long long args[] = {
+ HP_ENVY_8824_FAN_PRIME_ARG,
+ HP_ENVY_8824_FAN_PRIME_AUTO,
+ };
+ unsigned long long value;
+ int ret;
+
+ ret = hp_envy_x360_8824_acpi_eval(HP_ENVY_8824_ACPI_FANW, args,
+ ARRAY_SIZE(args), &value);
+ if (ret)
+ return ret;
+
+ args[0] = HP_ENVY_8824_FAN_VALUE_ARG;
+ args[1] = HP_ENVY_8824_FAN_PRIME_MANUAL;
+ ret = hp_envy_x360_8824_acpi_eval(HP_ENVY_8824_ACPI_FANW, args,
+ ARRAY_SIZE(args), &value);
+ if (ret)
+ return ret;
+
+ hp_envy_x360_8824_pwm_mode = HP_ENVY_8824_PWM_MODE_AUTO;
+ return 0;
+}
+
+static int hp_envy_x360_8824_set_manual_locked(void)
+{
+ int pwm;
+
+ pwm = hp_envy_x360_8824_get_pwm_locked();
+ if (pwm < 0)
+ return pwm;
+
+ return hp_envy_x360_8824_set_pwm_locked(pwm);
+}
+
/*
* Calling this hp_wmi_get_fan_count_userdefine_trigger function also enables
* and/or maintains the laptop in user defined thermal and fan states, instead
@@ -2103,6 +2227,12 @@ static void hp_wmi_rfkill_setup(struct platform_device *device)
rfkill_unregister(wifi_rfkill);
rfkill_destroy(wifi_rfkill);
}
+
+ if (is_envy_x360_8824_board) {
+ mutex_lock(&hp_envy_x360_8824_fan_lock);
+ hp_envy_x360_8824_set_auto_locked();
+ mutex_unlock(&hp_envy_x360_8824_fan_lock);
+ }
if (bluetooth_rfkill) {
rfkill_unregister(bluetooth_rfkill);
rfkill_destroy(bluetooth_rfkill);
@@ -2176,6 +2306,10 @@ static umode_t hp_wmi_hwmon_is_visible(const void *data,
{
switch (type) {
case hwmon_pwm:
+ if (attr == hwmon_pwm_input)
+ return is_envy_x360_8824_board ? 0644 : 0;
+ if (attr == hwmon_pwm_enable)
+ return is_envy_x360_8824_board ? 0644 : 0;
return 0644;
case hwmon_fan:
if (is_envy_x360_8824_board)
@@ -2213,6 +2347,25 @@ static int hp_wmi_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
*val = ret;
return 0;
case hwmon_pwm:
+ if (is_envy_x360_8824_board) {
+ mutex_lock(&hp_envy_x360_8824_fan_lock);
+ if (attr == hwmon_pwm_input) {
+ ret = hp_envy_x360_8824_get_pwm_locked();
+ if (!ret)
+ *val = ret;
+ else if (ret > 0)
+ *val = ret;
+ mutex_unlock(&hp_envy_x360_8824_fan_lock);
+ return ret < 0 ? ret : 0;
+ }
+ if (attr == hwmon_pwm_enable) {
+ *val = hp_envy_x360_8824_pwm_mode;
+ mutex_unlock(&hp_envy_x360_8824_fan_lock);
+ return 0;
+ }
+ mutex_unlock(&hp_envy_x360_8824_fan_lock);
+ return -EOPNOTSUPP;
+ }
switch (hp_wmi_fan_speed_max_get()) {
case 0:
/* 0 is automatic fan, which is 2 for hwmon */
@@ -2236,8 +2389,40 @@ static int hp_wmi_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
static int hp_wmi_hwmon_write(struct device *dev, enum hwmon_sensor_types type,
u32 attr, int channel, long val)
{
+ int ret;
+
switch (type) {
case hwmon_pwm:
+ if (is_envy_x360_8824_board) {
+ mutex_lock(&hp_envy_x360_8824_fan_lock);
+ switch (attr) {
+ case hwmon_pwm_input:
+ if (val < 0 || val > U8_MAX) {
+ mutex_unlock(&hp_envy_x360_8824_fan_lock);
+ return -EINVAL;
+ }
+ ret = hp_envy_x360_8824_set_pwm_locked(val);
+ mutex_unlock(&hp_envy_x360_8824_fan_lock);
+ return ret;
+ case hwmon_pwm_enable:
+ switch (val) {
+ case HP_ENVY_8824_PWM_MODE_MANUAL:
+ ret = hp_envy_x360_8824_set_manual_locked();
+ break;
+ case HP_ENVY_8824_PWM_MODE_AUTO:
+ ret = hp_envy_x360_8824_set_auto_locked();
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+ mutex_unlock(&hp_envy_x360_8824_fan_lock);
+ return ret;
+ default:
+ mutex_unlock(&hp_envy_x360_8824_fan_lock);
+ return -EOPNOTSUPP;
+ }
+ }
switch (val) {
case 0:
if (is_victus_s_thermal_profile())
@@ -2262,7 +2447,7 @@ static int hp_wmi_hwmon_write(struct device *dev, enum hwmon_sensor_types type,
static const struct hwmon_channel_info * const info[] = {
HWMON_CHANNEL_INFO(fan, HWMON_F_INPUT, HWMON_F_INPUT),
- HWMON_CHANNEL_INFO(pwm, HWMON_PWM_ENABLE),
+ HWMON_CHANNEL_INFO(pwm, HWMON_PWM_INPUT | HWMON_PWM_ENABLE),
NULL
};
--
2.48.1On Sun, 29 Mar 2026, Bani Brata wrote:
> On the HP ENVY x360 Convertible 13-bd0xxx (board 8824), standard WMI
> methods for fan speed control and RPM reporting do not function.
>
> However, the DSDT exposes ACPI methods (\_SB.PC00.LPCB.EC0.FANG and FANW)
> that allow reading and writing an 8-bit PWM level (0-255) to the EC.
>
> This patch maps these ACPI methods to standard hwmon `pwm1` and
> `pwm1_enable` nodes, allowing userspace tools to successfully control
> the fan speed.
>
> Signed-off-by: Bani Brata <banibrata2007@gmail.com>
> ---
> drivers/platform/x86/hp/hp-wmi.c | 155 ++++++++++++++++++++++++++++++-
> 1 file changed, 155 insertions(+)
>
> diff --git a/drivers/platform/x86/hp/hp-wmi.c b/drivers/platform/x86/hp/hp-wmi.c
> index XXXXXXX..XXXXXXX 100644
> --- a/drivers/platform/x86/hp/hp-wmi.c
> +++ b/drivers/platform/x86/hp/hp-wmi.c
> @@ -48,6 +48,14 @@
> #define HP_FAN_SPEED_AUTOMATIC 0x00
> #define HP_POWER_LIMIT_DEFAULT 0x00
> #define HP_POWER_LIMIT_NO_CHANGE 0xFF
> +#define HP_ENVY_8824_ACPI_FANG "\\_SB.PC00.LPCB.EC0.FANG"
> +#define HP_ENVY_8824_ACPI_FANW "\\_SB.PC00.LPCB.EC0.FANW"
> +#define HP_ENVY_8824_FAN_VALUE_ARG 33026ULL
> +#define HP_ENVY_8824_FAN_PRIME_ARG 33030ULL
> +#define HP_ENVY_8824_FAN_PRIME_MANUAL 0xFFULL
> +#define HP_ENVY_8824_FAN_PRIME_AUTO 0x8ULL
> +#define HP_ENVY_8824_PWM_MODE_MANUAL 1
> +#define HP_ENVY_8824_PWM_MODE_AUTO 2
>
> #define ACPI_AC_CLASS "ac_adapter"
>
> @@ -193,6 +201,8 @@ static const struct dmi_system_id hp_wmi_rfkill_dmi_table[] __initconst = {
>
> static bool is_victus_s_board;
> static bool is_envy_x360_8824_board;
> +static DEFINE_MUTEX(hp_envy_x360_8824_fan_lock);
> +static int hp_envy_x360_8824_pwm_mode = HP_ENVY_8824_PWM_MODE_AUTO;
>
> static const struct dmi_system_id hp_envy_x360_8824_boards[] __initconst = {
> {
> @@ -518,6 +528,120 @@ static int hp_wmi_get_fan_speed_victus_s(int fan)
> return ret;
> }
>
> +static int hp_envy_x360_8824_acpi_eval(const char *path,
> + const unsigned long long *args,
> + size_t arg_count,
> + unsigned long long *value)
> +{
> + struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
> + union acpi_object params[2] = { };
> + struct acpi_object_list input = { .count = arg_count, .pointer = params };
> + union acpi_object *obj;
> + acpi_status status;
> + size_t i;
> +
> + for (i = 0; i < arg_count; i++) {
> + params[i].type = ACPI_TYPE_INTEGER;
> + params[i].integer.value = args[i];
> + }
> +
> + status = acpi_evaluate_object(NULL, (acpi_string)path,
> + arg_count ? &input : NULL, &output);
> + if (ACPI_FAILURE(status))
> + return -EIO;
> +
> + obj = output.pointer;
Please move variable declaration here and use __free() so you don't need
to do manual kfree()s.
> + if (!obj)
> + return -ENODATA;
> +
> + if (obj->type != ACPI_TYPE_INTEGER) {
> + kfree(obj);
> + return -EINVAL;
> + }
> +
> + *value = obj->integer.value;
> + kfree(obj);
> +
> + return 0;
> +}
> +
> +static int hp_envy_x360_8824_get_pwm_locked(void)
> +{
> + unsigned long long args[] = { HP_ENVY_8824_FAN_VALUE_ARG };
> + unsigned long long value;
> + int ret;
> +
> + ret = hp_envy_x360_8824_acpi_eval(HP_ENVY_8824_ACPI_FANG, args,
> + ARRAY_SIZE(args), &value);
> + if (ret)
> + return ret;
> + if (value > U8_MAX)
> + return -EINVAL;
> +
> + return value;
> +}
> +
> +static int hp_envy_x360_8824_set_pwm_locked(u8 pwm)
> +{
> + unsigned long long args[] = {
> + HP_ENVY_8824_FAN_PRIME_ARG,
> + HP_ENVY_8824_FAN_PRIME_MANUAL,
> + };
> + unsigned long long value;
> + int ret;
> +
> + ret = hp_envy_x360_8824_acpi_eval(HP_ENVY_8824_ACPI_FANW, args,
> + ARRAY_SIZE(args), &value);
> + if (ret)
> + return ret;
> +
> + args[0] = HP_ENVY_8824_FAN_VALUE_ARG;
> + args[1] = pwm;
> + ret = hp_envy_x360_8824_acpi_eval(HP_ENVY_8824_ACPI_FANW, args,
> + ARRAY_SIZE(args), &value);
> + if (ret)
> + return ret;
> +
> + hp_envy_x360_8824_pwm_mode = HP_ENVY_8824_PWM_MODE_MANUAL;
> + return 0;
> +}
> +
> +static int hp_envy_x360_8824_set_auto_locked(void)
> +{
> + unsigned long long args[] = {
> + HP_ENVY_8824_FAN_PRIME_ARG,
> + HP_ENVY_8824_FAN_PRIME_AUTO,
> + };
> + unsigned long long value;
> + int ret;
> +
> + ret = hp_envy_x360_8824_acpi_eval(HP_ENVY_8824_ACPI_FANW, args,
> + ARRAY_SIZE(args), &value);
> + if (ret)
> + return ret;
> +
> + args[0] = HP_ENVY_8824_FAN_VALUE_ARG;
> + args[1] = HP_ENVY_8824_FAN_PRIME_MANUAL;
> + ret = hp_envy_x360_8824_acpi_eval(HP_ENVY_8824_ACPI_FANW, args,
> + ARRAY_SIZE(args), &value);
> + if (ret)
> + return ret;
> +
> + hp_envy_x360_8824_pwm_mode = HP_ENVY_8824_PWM_MODE_AUTO;
> + return 0;
> +}
> +
> +static int hp_envy_x360_8824_set_manual_locked(void)
> +{
> + int pwm;
> +
> + pwm = hp_envy_x360_8824_get_pwm_locked();
> + if (pwm < 0)
> + return pwm;
> +
> + return hp_envy_x360_8824_set_pwm_locked(pwm);
> +}
> +
> /*
> * Calling this hp_wmi_get_fan_count_userdefine_trigger function also enables
> * and/or maintains the laptop in user defined thermal and fan states, instead
> @@ -2103,6 +2227,12 @@ static void hp_wmi_rfkill_setup(struct platform_device *device)
> rfkill_unregister(wifi_rfkill);
> rfkill_destroy(wifi_rfkill);
> }
> +
> + if (is_envy_x360_8824_board) {
> + mutex_lock(&hp_envy_x360_8824_fan_lock);
> + hp_envy_x360_8824_set_auto_locked();
> + mutex_unlock(&hp_envy_x360_8824_fan_lock);
Use guard().
> + }
> if (bluetooth_rfkill) {
> rfkill_unregister(bluetooth_rfkill);
> rfkill_destroy(bluetooth_rfkill);
> @@ -2176,6 +2306,10 @@ static umode_t hp_wmi_hwmon_is_visible(const void *data,
> {
> switch (type) {
> case hwmon_pwm:
> + if (attr == hwmon_pwm_input)
> + return is_envy_x360_8824_board ? 0644 : 0;
> + if (attr == hwmon_pwm_enable)
> + return is_envy_x360_8824_board ? 0644 : 0;
> return 0644;
> case hwmon_fan:
> if (is_envy_x360_8824_board)
> @@ -2213,6 +2347,25 @@ static int hp_wmi_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
> *val = ret;
> return 0;
> case hwmon_pwm:
> + if (is_envy_x360_8824_board) {
> + mutex_lock(&hp_envy_x360_8824_fan_lock);
> + if (attr == hwmon_pwm_input) {
Why you need to do this under lock?
Also, use guard() instead of lock/unlock pair.
> + ret = hp_envy_x360_8824_get_pwm_locked();
> + if (!ret)
> + *val = ret;
> + else if (ret > 0)
> + *val = ret;
Aren't these same as ret >= 0. However, with guard(), you can reverse the
logic and return error immediately so I don't think you need other if()s
at all.
> + mutex_unlock(&hp_envy_x360_8824_fan_lock);
> + return ret < 0 ? ret : 0;
> + }
> + if (attr == hwmon_pwm_enable) {
> + *val = hp_envy_x360_8824_pwm_mode;
> + mutex_unlock(&hp_envy_x360_8824_fan_lock);
> + return 0;
> + }
> + mutex_unlock(&hp_envy_x360_8824_fan_lock);
> + return -EOPNOTSUPP;
> + }
> switch (hp_wmi_fan_speed_max_get()) {
> case 0:
> /* 0 is automatic fan, which is 2 for hwmon */
> @@ -2236,8 +2389,40 @@ static int hp_wmi_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
> static int hp_wmi_hwmon_write(struct device *dev, enum hwmon_sensor_types type,
> u32 attr, int channel, long val)
> {
> + int ret;
> +
> switch (type) {
> case hwmon_pwm:
> + if (is_envy_x360_8824_board) {
> + mutex_lock(&hp_envy_x360_8824_fan_lock);
> + switch (attr) {
> + case hwmon_pwm_input:
> + if (val < 0 || val > U8_MAX) {
> + mutex_unlock(&hp_envy_x360_8824_fan_lock);
> + return -EINVAL;
> + }
Here too, isn't it enough to begin the critical section only here?
Again, please use guard() instead.
> + ret = hp_envy_x360_8824_set_pwm_locked(val);
> + mutex_unlock(&hp_envy_x360_8824_fan_lock);
> + return ret;
> + case hwmon_pwm_enable:
> + switch (val) {
> + case HP_ENVY_8824_PWM_MODE_MANUAL:
> + ret = hp_envy_x360_8824_set_manual_locked();
> + break;
> + case HP_ENVY_8824_PWM_MODE_AUTO:
> + ret = hp_envy_x360_8824_set_auto_locked();
> + break;
> + default:
> + ret = -EINVAL;
> + break;
> + }
> + mutex_unlock(&hp_envy_x360_8824_fan_lock);
> + return ret;
> + default:
> + mutex_unlock(&hp_envy_x360_8824_fan_lock);
This default path doesn't require taking the mutex.
> + return -EOPNOTSUPP;
> + }
> + }
> switch (val) {
> case 0:
> if (is_victus_s_thermal_profile())
> @@ -2262,7 +2447,7 @@ static int hp_wmi_hwmon_write(struct device *dev, enum hwmon_sensor_types type,
>
> static const struct hwmon_channel_info * const info[] = {
> HWMON_CHANNEL_INFO(fan, HWMON_F_INPUT, HWMON_F_INPUT),
> - HWMON_CHANNEL_INFO(pwm, HWMON_PWM_ENABLE),
> + HWMON_CHANNEL_INFO(pwm, HWMON_PWM_INPUT | HWMON_PWM_ENABLE),
> NULL
> };
>
>
--
i.
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