[RESEND PATCH 2/5] platform/x86: bitland-mifs-wmi: support MIFS v2 perf-mode mapping

["孙 誉铭" <wolf109909@outlook.com>]

The MIFS v2 firmware found on e.g. the Xiaomi Book Pro 14 2026 (Intel
Panther Lake, SSDT device "WMID" with _UID "MIFS") implements only a
reduced WMAA command set and reports the performance mode as raw QFAN
embedded-controller codes { 2, 3, 4, 9, 10 } instead of the v1 0..3
enumeration. With the v1 mapping, profile_get() returns -EINVAL for
most firmware states ("platform_profile: Failed to get profile for
handler bitland-mifs-wmi", also reported on REDMI Book Pro 14 2025)
and profile_set() writes values the firmware treats as no-ops, so
power-profiles-daemon can neither read nor switch the profile;
selecting "performance" fails outright and wedges the daemon.

Detect the variant at probe time by querying the current mode: values
outside the v1 enumeration mean v2 firmware. Map the v2 codes to
platform profiles (2=quiet, 3=balanced, 4=speed, 9/10=extreme) and
skip the v1-only AC-type capability probe, which does not exist on v2
and now fails the call after the status-word check.

Values verified against the laptop's SSDT WMAA method and by observing
the EC QFAN register while switching modes.

Signed-off-by: Yuming Sun <wolf109909@outlook.com>
---
 drivers/platform/x86/bitland-mifs-wmi.c | 79 +++++++++++++++++++++++++
 1 file changed, 79 insertions(+)

diff --git a/drivers/platform/x86/bitland-mifs-wmi.c b/drivers/platform/x86/bitland-mifs-wmi.c
index 12426d11..342dd7e1 100644
--- a/drivers/platform/x86/bitland-mifs-wmi.c
+++ b/drivers/platform/x86/bitland-mifs-wmi.c
@@ -73,6 +73,21 @@ enum bitland_mifs_power_profile {
 	WMI_PP_FULL_SPEED	= 3,
 };
 
+/*
+ * MIFS v2 firmware (e.g. Xiaomi Book Pro 14 2026, SSDT "WMID" with UID
+ * "MIFS") implements a reduced WMAA command set (only function groups
+ * 0x0800/0x0a00/0x0c00/0x1000) and reports the performance mode as raw
+ * QFAN EC codes instead of the v1 0..3 enumeration. Codes 9 and 10 are
+ * the SMM-backed "extreme" modes.
+ */
+enum bitland_mifs_v2_power_profile {
+	WMI_V2_PP_QUIET		= 2,
+	WMI_V2_PP_BALANCED	= 3,
+	WMI_V2_PP_SPEED		= 4,
+	WMI_V2_PP_EXTREME	= 9,
+	WMI_V2_PP_EXTREME2	= 10,
+};
+
 enum bitland_mifs_event_id {
 	WMI_EVENT_RESERVED_1		= 1,
 	WMI_EVENT_RESERVED_2		= 2,
@@ -172,6 +187,7 @@ struct bitland_mifs_wmi_data {
 	struct device *pp_dev;
 	enum platform_profile_option saved_profile;
 	bool profile_valid;
+	bool is_v2;	/* MIFS v2 firmware: QFAN perf-mode codes */
 };
 
 static int bitland_mifs_wmi_call(struct bitland_mifs_wmi_data *data,
@@ -217,6 +233,27 @@ static int laptop_profile_get(struct device *dev,
 	if (ret)
 		return ret;
 
+	if (data->is_v2) {
+		switch (result.data[0]) {
+		case WMI_V2_PP_QUIET:
+			*profile = PLATFORM_PROFILE_LOW_POWER;
+			break;
+		case WMI_V2_PP_BALANCED:
+			*profile = PLATFORM_PROFILE_BALANCED;
+			break;
+		case WMI_V2_PP_SPEED:
+			*profile = PLATFORM_PROFILE_BALANCED_PERFORMANCE;
+			break;
+		case WMI_V2_PP_EXTREME:
+		case WMI_V2_PP_EXTREME2:
+			*profile = PLATFORM_PROFILE_PERFORMANCE;
+			break;
+		default:
+			return -EINVAL;
+		}
+		return 0;
+	}
+
 	switch (result.data[0]) {
 	case WMI_PP_BALANCED:
 		*profile = PLATFORM_PROFILE_BALANCED;
@@ -272,6 +309,28 @@ static int laptop_profile_set(struct device *dev,
 	int ret;
 	u8 val;
 
+	if (data->is_v2) {
+		switch (profile) {
+		case PLATFORM_PROFILE_LOW_POWER:
+			val = WMI_V2_PP_QUIET;
+			break;
+		case PLATFORM_PROFILE_BALANCED:
+			val = WMI_V2_PP_BALANCED;
+			break;
+		case PLATFORM_PROFILE_BALANCED_PERFORMANCE:
+			val = WMI_V2_PP_SPEED;
+			break;
+		case PLATFORM_PROFILE_PERFORMANCE:
+			val = WMI_V2_PP_EXTREME;
+			break;
+		default:
+			return -EOPNOTSUPP;
+		}
+		input.payload[0] = val;
+
+		return bitland_mifs_wmi_call(data, &input, NULL);
+	}
+
 	switch (profile) {
 	case PLATFORM_PROFILE_LOW_POWER:
 		val = WMI_PP_QUIET;
@@ -705,6 +764,26 @@ static int bitland_mifs_wmi_probe(struct wmi_device *wdev, const void *context)
 
 	dev_set_drvdata(&wdev->dev, drv_data);
 
+	if (dev_type == BITLAND_WMI_CONTROL) {
+		/*
+		 * Firmware variant detection: v1 firmware reports the perf mode
+		 * as 0..3 (enum bitland_mifs_power_profile); anything else means
+		 * the reduced MIFS v2 command set with raw QFAN codes.
+		 */
+		struct bitland_mifs_input probe_in = {
+			.operation = WMI_METHOD_GET,
+			.function = WMI_FN_SYSTEM_PER_MODE,
+		};
+		struct bitland_mifs_output probe_out;
+
+		if (!bitland_mifs_wmi_call(drv_data, &probe_in, &probe_out) &&
+		    probe_out.data[0] > WMI_PP_FULL_SPEED) {
+			drv_data->is_v2 = true;
+			dev_info(&wdev->dev,
+				 "MIFS v2 firmware detected (QFAN mode codes)\n");
+		}
+	}
+
 	if (dev_type == BITLAND_WMI_EVENT) {
 		/* Register input device for hotkeys */
 		drv_data->input_dev = devm_input_allocate_device(&wdev->dev);
-- 
2.55.0