[PATCH v5 04/14] platform/x86: alienware-wmi: Refactor LED control methods

Kurt Borja
2025-01-19T22:06:05Z

Both WMI devices handled by this module specify a distinct interface for
LED control. Previously this module handled this by dynamically adapting
arguments passed to wmi_evaluate_method() based on the `interface`
global variable.

To avoid the use of global variables, and enable the migration to
non-deprecated WMI methods, let the WMI drivers define upd_led and
upd_brightness operations, which completely replace
alienware_update_led() and wmax_brightness().

Also define alienware_wmi_command(), which serves as a wrapper for
wmidev_evaluate_method(). This new method is very similar to
alienware_wmax_command() but is WMI device agnostic.

Reviewed-by: Armin Wolf <W_Armin@gmx.de>
Signed-off-by: Kurt Borja <kuurtb@gmail.com>
---
drivers/platform/x86/dell/alienware-wmi.c | 166 ++++++++++++++--------
1 file changed, 104 insertions(+), 62 deletions(-)

diff --git a/drivers/platform/x86/dell/alienware-wmi.c b/drivers/platform/x86/dell/alienware-wmi.c
index 9328bf9b6c81..18f3a619283e 100644
--- a/drivers/platform/x86/dell/alienware-wmi.c
+++ b/drivers/platform/x86/dell/alienware-wmi.c
@@ -10,6 +10,7 @@
#include <linux/acpi.h>
#include <linux/bitfield.h>
#include <linux/bits.h>
+#include <linux/cleanup.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/platform_profile.h>
@@ -417,12 +418,43 @@ struct alienfx_priv {
u8 lighting_control_state;
};

+struct alienfx_ops {
+ int (*upd_led)(struct alienfx_priv *priv, struct wmi_device *wdev,
+ u8 location);
+ int (*upd_brightness)(struct alienfx_priv *priv, struct wmi_device *wdev,
+ u8 brightness);
+};
+
struct alienfx_platdata {
struct wmi_device *wdev;
+ struct alienfx_ops ops;
};

static u8 interface;

+static int alienware_wmi_command(struct wmi_device *wdev, u32 method_id,
+ void *in_args, size_t in_size, u32 *out_data)
+{
+ struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
+ struct acpi_buffer in = {in_size, in_args};
+ acpi_status ret;
+
+ ret = wmidev_evaluate_method(wdev, 0, method_id, &in, out_data ? &out : NULL);
+ if (ACPI_FAILURE(ret))
+ return -EIO;
+
+ union acpi_object *obj __free(kfree) = out.pointer;
+
+ if (out_data) {
+ if (obj && obj->type == ACPI_TYPE_INTEGER)
+ *out_data = (u32)obj->integer.value;
+ else
+ return -ENOMSG;
+ }
+
+ return 0;
+}
+
/*
* Helpers used for zone control
*/
@@ -453,46 +485,6 @@ static int parse_rgb(const char *buf, struct color_platform *colors)
/*
* Individual RGB zone control
*/
-static int alienware_update_led(struct alienfx_priv *priv, u8 location)
-{
- int method_id;
- acpi_status status;
- char *guid;
- struct acpi_buffer input;
- struct legacy_led_args legacy_args;
- struct wmax_led_args wmax_basic_args;
- if (interface == WMAX) {
- wmax_basic_args.led_mask = 1 << location;
- wmax_basic_args.colors = priv->colors[location];
- wmax_basic_args.state = priv->lighting_control_state;
- guid = WMAX_CONTROL_GUID;
- method_id = WMAX_METHOD_ZONE_CONTROL;
-
- input.length = sizeof(wmax_basic_args);
- input.pointer = &wmax_basic_args;
- } else {
- legacy_args.colors = priv->colors[location];
- legacy_args.brightness = priv->global_brightness;
- legacy_args.state = 0;
- if (priv->lighting_control_state == LEGACY_BOOTING ||
- priv->lighting_control_state == LEGACY_SUSPEND) {
- guid = LEGACY_POWER_CONTROL_GUID;
- legacy_args.state = priv->lighting_control_state;
- } else
- guid = LEGACY_CONTROL_GUID;
- method_id = location + 1;
-
- input.length = sizeof(legacy_args);
- input.pointer = &legacy_args;
- }
- pr_debug("alienware-wmi: guid %s method %d\n", guid, method_id);
-
- status = wmi_evaluate_method(guid, 0, method_id, &input, NULL);
- if (ACPI_FAILURE(status))
- pr_err("alienware-wmi: zone set failure: %u\n", status);
- return ACPI_FAILURE(status);
-}
-
static ssize_t zone_show(struct device *dev, struct device_attribute *attr,
char *buf, u8 location)
{
@@ -509,13 +501,14 @@ static ssize_t zone_store(struct device *dev, struct device_attribute *attr,
{
struct alienfx_priv *priv = dev_get_drvdata(dev);
struct color_platform *colors = &priv->colors[location];
+ struct alienfx_platdata *pdata = dev_get_platdata(dev);
int ret;

ret = parse_rgb(buf, colors);
if (ret)
return ret;

- ret = alienware_update_led(priv, location);
+ ret = pdata->ops.upd_led(priv, pdata->wdev, location);

return ret ? ret : count;
}
@@ -651,36 +644,17 @@ static struct attribute_group zone_attribute_group = {
/*
* LED Brightness (Global)
*/
-static int wmax_brightness(int brightness)
-{
- acpi_status status;
- struct acpi_buffer input;
- struct wmax_brightness_args args = {
- .led_mask = 0xFF,
- .percentage = brightness,
- };
- input.length = sizeof(args);
- input.pointer = &args;
- status = wmi_evaluate_method(WMAX_CONTROL_GUID, 0,
- WMAX_METHOD_BRIGHTNESS, &input, NULL);
- if (ACPI_FAILURE(status))
- pr_err("alienware-wmi: brightness set failure: %u\n", status);
- return ACPI_FAILURE(status);
-}
-
static void global_led_set(struct led_classdev *led_cdev,
enum led_brightness brightness)
{
struct alienfx_priv *priv = container_of(led_cdev, struct alienfx_priv,
global_led);
+ struct alienfx_platdata *pdata = dev_get_platdata(&priv->pdev->dev);
int ret;

priv->global_brightness = brightness;

- if (interface == WMAX)
- ret = wmax_brightness(brightness);
- else
- ret = alienware_update_led(priv, 0);
+ ret = pdata->ops.upd_brightness(priv, pdata->wdev, brightness);
if (ret)
pr_err("LED brightness update failed\n");
}
@@ -1223,10 +1197,49 @@ static void alienware_alienfx_exit(struct wmi_device *wdev)
/*
* Legacy WMI driver
*/
+static int legacy_wmi_update_led(struct alienfx_priv *priv,
+ struct wmi_device *wdev, u8 location)
+{
+ struct legacy_led_args legacy_args = {
+ .colors = priv->colors[location],
+ .brightness = priv->global_brightness,
+ .state = 0,
+ };
+ struct acpi_buffer input;
+ acpi_status status;
+
+ if (legacy_args.state != LEGACY_RUNNING) {
+ legacy_args.state = priv->lighting_control_state;
+
+ input.length = sizeof(legacy_args);
+ input.pointer = &legacy_args;
+
+ status = wmi_evaluate_method(LEGACY_POWER_CONTROL_GUID, 0,
+ location + 1, &input, NULL);
+ if (ACPI_FAILURE(status))
+ return -EIO;
+
+ return 0;
+ }
+
+ return alienware_wmi_command(wdev, location + 1, &legacy_args,
+ sizeof(legacy_args), NULL);
+}
+
+static int legacy_wmi_update_brightness(struct alienfx_priv *priv,
+ struct wmi_device *wdev, u8 brightness)
+{
+ return legacy_wmi_update_led(priv, wdev, 0);
+}
+
static int legacy_wmi_probe(struct wmi_device *wdev, const void *context)
{
struct alienfx_platdata pdata = {
.wdev = wdev,
+ .ops = {
+ .upd_led = legacy_wmi_update_led,
+ .upd_brightness = legacy_wmi_update_brightness,
+ },
};

return alienware_alienfx_setup(&pdata);
@@ -1267,10 +1280,39 @@ static void __exit alienware_legacy_wmi_exit(void)
/*
* WMAX WMI driver
*/
+static int wmax_wmi_update_led(struct alienfx_priv *priv,
+ struct wmi_device *wdev, u8 location)
+{
+ struct wmax_led_args in_args = {
+ .led_mask = 1 << location,
+ .colors = priv->colors[location],
+ .state = priv->lighting_control_state,
+ };
+
+ return alienware_wmi_command(wdev, WMAX_METHOD_ZONE_CONTROL, &in_args,
+ sizeof(in_args), NULL);
+}
+
+static int wmax_wmi_update_brightness(struct alienfx_priv *priv,
+ struct wmi_device *wdev, u8 brightness)
+{
+ struct wmax_brightness_args in_args = {
+ .led_mask = 0xFF,
+ .percentage = brightness,
+ };
+
+ return alienware_wmi_command(wdev, WMAX_METHOD_BRIGHTNESS, &in_args,
+ sizeof(in_args), NULL);
+}
+
static int wmax_wmi_probe(struct wmi_device *wdev, const void *context)
{
struct alienfx_platdata pdata = {
.wdev = wdev,
+ .ops = {
+ .upd_led = wmax_wmi_update_led,
+ .upd_brightness = wmax_wmi_update_brightness,
+ },
};
struct platform_device *pdev;
int ret;
--
2.48.1