Re: [PATCH v6 03/12] platform/x86: alienware-wmi-wmax: Improve internal AWCC API

Ilpo Järvinen
2025-03-28T14:51:33Z

On Thu, 13 Mar 2025, Kurt Borja wrote:

> Inline all AWCC WMI helper methods and directly return the newly
> introduced __awcc_wmi_command() helper to simplify implementation.
>
> Drop awcc_thermal_control() in favor of awcc_op_activate_profile().
>
> Add awcc_op_get_resource_id(), awcc_op_get_current_profile() and a new
> failure code.
>
> Reviewed-by: Armin Wolf <W_Armin@gmx.de>
> Signed-off-by: Kurt Borja <kuurtb@gmail.com>
> ---
> drivers/platform/x86/dell/alienware-wmi-wmax.c | 150 +++++++++++++++----------
> 1 file changed, 91 insertions(+), 59 deletions(-)
>
> diff --git a/drivers/platform/x86/dell/alienware-wmi-wmax.c b/drivers/platform/x86/dell/alienware-wmi-wmax.c
> index 80aefba5b22d6b4ac18aeb2ca356f8c911150abd..b9dbfdc8096c571722b3c7ac3e73989e235e2eb9 100644
> --- a/drivers/platform/x86/dell/alienware-wmi-wmax.c
> +++ b/drivers/platform/x86/dell/alienware-wmi-wmax.c
> @@ -32,6 +32,7 @@
> #define AWCC_THERMAL_MODE_GMODE 0xAB
>
> #define AWCC_FAILURE_CODE 0xFFFFFFFF
> +#define AWCC_FAILURE_CODE_2 0xFFFFFFFE
> #define AWCC_THERMAL_TABLE_MASK GENMASK(7, 4)
> #define AWCC_THERMAL_MODE_MASK GENMASK(3, 0)
> /* Some IDs have a BIT(8) flag that we ignore */
> @@ -443,8 +444,7 @@ const struct attribute_group wmax_deepsleep_attribute_group = {
> };
>
> /*
> - * Thermal Profile control
> - * - Provides thermal profile control through the Platform Profile API
> + * AWCC Helpers
> */
> static bool is_awcc_thermal_profile_id(u8 code)
> {
> @@ -463,72 +463,107 @@ static bool is_awcc_thermal_profile_id(u8 code)
> return false;
> }
>
> -static int awcc_thermal_information(struct wmi_device *wdev, u8 operation,
> - u8 arg, u32 *out_data)
> +static int __awcc_wmi_command(struct wmi_device *wdev, u32 method_id,
> + struct wmax_u32_args *args, u32 *out)

Why did you put __ into the name?

Some people oppose __ prefix altogether, I don't entirely agree with their
stance but I don't really understand what the underscores here signify.

Normally I see __ being used in three main cases:
- non-__ variant does some locking around the call too the __ func (though
many funcs use _locked postfix these days).
- func is "dangerous" and caller has to really know what he/she is
doing / be careful for some reason.
- non-__ variant exists and somebody cannot come up better name for the
internally called function (not very good use case, IMHO)

I don't see any of those apply here, this looks just an ordinary wrapper
function, thus the question.

> {
> - struct wmax_u32_args in_args = {
> + int ret;
> +
> + ret = alienware_wmi_command(wdev, method_id, args, sizeof(*args), out);
> + if (ret)
> + return ret;
> +
> + if (*out == AWCC_FAILURE_CODE || *out == AWCC_FAILURE_CODE_2)
> + return -EBADRQC;
> +
> + return 0;
> +}
> +
> +static inline int awcc_thermal_information(struct wmi_device *wdev, u8 operation,
> + u8 arg, u32 *out)
> +{
> + struct wmax_u32_args args = {
> .operation = operation,
> .arg1 = arg,
> .arg2 = 0,
> .arg3 = 0,
> };
> - int ret;
>
> - ret = alienware_wmi_command(wdev, AWCC_METHOD_THERMAL_INFORMATION,
> - &in_args, sizeof(in_args), out_data);
> - if (ret < 0)
> - return ret;
> -
> - if (*out_data == AWCC_FAILURE_CODE)
> - return -EBADRQC;
> -
> - return 0;
> + return __awcc_wmi_command(wdev, AWCC_METHOD_THERMAL_INFORMATION, &args, out);
> }
>
> -static int awcc_thermal_control(struct wmi_device *wdev, u8 profile)
> +static inline int awcc_game_shift_status(struct wmi_device *wdev, u8 operation,

As a general rule, don't add inline to .c files, we leave figuring
inlining out to the compiler.

> + u32 *out)
> {
> - struct wmax_u32_args in_args = {
> - .operation = AWCC_OP_ACTIVATE_PROFILE,
> - .arg1 = profile,
> - .arg2 = 0,
> - .arg3 = 0,
> - };
> - u32 out_data;
> - int ret;
> -
> - ret = alienware_wmi_command(wdev, AWCC_METHOD_THERMAL_CONTROL,
> - &in_args, sizeof(in_args), &out_data);
> - if (ret)
> - return ret;
> -
> - if (out_data == AWCC_FAILURE_CODE)
> - return -EBADRQC;
> -
> - return 0;
> -}
> -
> -static int awcc_game_shift_status(struct wmi_device *wdev, u8 operation,
> - u32 *out_data)
> -{
> - struct wmax_u32_args in_args = {
> + struct wmax_u32_args args = {
> .operation = operation,
> .arg1 = 0,
> .arg2 = 0,
> .arg3 = 0,
> };
> - int ret;
>
> - ret = alienware_wmi_command(wdev, AWCC_METHOD_GAME_SHIFT_STATUS,
> - &in_args, sizeof(in_args), out_data);
> - if (ret < 0)
> - return ret;
> -
> - if (*out_data == AWCC_FAILURE_CODE)
> - return -EOPNOTSUPP;
> -
> - return 0;
> + return __awcc_wmi_command(wdev, AWCC_METHOD_GAME_SHIFT_STATUS, &args, out);
> }
>
> +/**
> + * awcc_op_get_resource_id - Get the resource ID at a given index
> + * @wdev: AWCC WMI device
> + * @index: Index
> + * @out: Value returned by the WMI call
> + *
> + * Get the resource ID at a given index. Resource IDs are listed in the

Use @index to refer to the argument.

> + * following order:
> + *
> + * - Fan IDs
> + * - Sensor IDs
> + * - Unknown IDs
> + * - Thermal Profile IDs
> + *
> + * The total number of IDs of a given type can be obtained with
> + * AWCC_OP_GET_SYSTEM_DESCRIPTION.
> + *
> + * Return: 0 on success, -errno on failure
> + */
> +static inline int awcc_op_get_resource_id(struct wmi_device *wdev, u8 index, u32 *out)
> +{
> + struct wmax_u32_args args = {
> + .operation = AWCC_OP_GET_RESOURCE_ID,
> + .arg1 = index,
> + .arg2 = 0,
> + .arg3 = 0,
> + };
> +
> + return __awcc_wmi_command(wdev, AWCC_METHOD_THERMAL_INFORMATION, &args, out);
> +}
> +
> +static inline int awcc_op_get_current_profile(struct wmi_device *wdev, u32 *out)
> +{
> + struct wmax_u32_args args = {
> + .operation = AWCC_OP_GET_CURRENT_PROFILE,
> + .arg1 = 0,
> + .arg2 = 0,
> + .arg3 = 0,
> + };
> +
> + return __awcc_wmi_command(wdev, AWCC_METHOD_THERMAL_INFORMATION, &args, out);
> +}
> +
> +static inline int awcc_op_activate_profile(struct wmi_device *wdev, u8 profile)
> +{
> + struct wmax_u32_args args = {
> + .operation = AWCC_OP_ACTIVATE_PROFILE,
> + .arg1 = profile,
> + .arg2 = 0,
> + .arg3 = 0,
> + };
> + u32 out;
> +
> + return __awcc_wmi_command(wdev, AWCC_METHOD_THERMAL_CONTROL, &args, &out);
> +}
> +
> +/*
> + * Thermal Profile control
> + * - Provides thermal profile control through the Platform Profile API
> + */
> static int awcc_platform_profile_get(struct device *dev,
> enum platform_profile_option *profile)
> {
> @@ -536,10 +571,8 @@ static int awcc_platform_profile_get(struct device *dev,
> u32 out_data;
> int ret;
>
> - ret = awcc_thermal_information(priv->wdev, AWCC_OP_GET_CURRENT_PROFILE,
> - 0, &out_data);
> -
> - if (ret < 0)
> + ret = awcc_op_get_current_profile(priv->wdev, &out_data);
> + if (ret)
> return ret;
>
> if (out_data == AWCC_THERMAL_MODE_GMODE) {
> @@ -550,7 +583,7 @@ static int awcc_platform_profile_get(struct device *dev,
> if (!is_awcc_thermal_profile_id(out_data))
> return -ENODATA;
>
> - out_data &= AWCC_THERMAL_MODE_MASK;
> + out_data = FIELD_GET(AWCC_THERMAL_MODE_MASK, out_data);

Should this be part of the earlier patch??

> *profile = awcc_mode_to_platform_profile[out_data];
>
> return 0;
> @@ -583,8 +616,8 @@ static int awcc_platform_profile_set(struct device *dev,
> }
> }
>
> - return awcc_thermal_control(priv->wdev,
> - priv->supported_thermal_profiles[profile]);
> + return awcc_op_activate_profile(priv->wdev,
> + priv->supported_thermal_profiles[profile]);
> }
>
> static int awcc_platform_profile_probe(void *drvdata, unsigned long *choices)
> @@ -606,8 +639,7 @@ static int awcc_platform_profile_probe(void *drvdata, unsigned long *choices)
> first_mode = sys_desc[0] + sys_desc[1];
>
> for (u32 i = 0; i < sys_desc[3]; i++) {
> - ret = awcc_thermal_information(priv->wdev, AWCC_OP_GET_RESOURCE_ID,
> - i + first_mode, &out_data);
> + ret = awcc_op_get_resource_id(priv->wdev, i + first_mode, &out_data);
>
> if (ret == -EIO)
> return ret;
>
>

--
i.