[PATCH v6 5/5] platform/x86: bitland-mifs-wmi: Add per-machine ops table

[Mingyou Chen <qby140326@gmail.com>]

The MIFS WMI interface is shared by several Bitland ODM laptops which
differ in the layout of the performance mode values of
WMI_FN_SYSTEM_PER_MODE and in the capability checks.

Introduce a machine ops table to support multiple machine families
without sprinkling model checks over the driver:

struct bitland_mifs_ops {
        const char *name;
        const struct bitland_profile_mode_map *mode_map;
        int (*check_performance_capability)(
                struct bitland_mifs_wmi_data *data);
        bool has_full_speed;
};

The default ops instance keeps the current Bitland behavior, so this
change is a pure refactor without any functional changes.

Signed-off-by: Mingyou Chen <qby140326@gmail.com>
---
 drivers/platform/x86/bitland-mifs-wmi.c | 108 +++++++++++++++++++-----
 1 file changed, 86 insertions(+), 22 deletions(-)

diff --git a/drivers/platform/x86/bitland-mifs-wmi.c b/drivers/platform/x86/bitland-mifs-wmi.c
index df317aa6f555..d092bf07b7f7 100644
--- a/drivers/platform/x86/bitland-mifs-wmi.c
+++ b/drivers/platform/x86/bitland-mifs-wmi.c
@@ -12,6 +12,7 @@
 #include <linux/bits.h>
 #include <linux/container_of.h>
 #include <linux/dev_printk.h>
+#include <linux/dmi.h>
 #include <linux/device.h>
 #include <linux/device/devres.h>
 #include <linux/err.h>
@@ -84,6 +85,50 @@ enum bitland_mifs_power_profile {
 	WMI_PP_FULL_SPEED	= 3,
 };
 
+struct bitland_mifs_wmi_data;
+
+/*
+ * Value layout of WMI_FN_SYSTEM_PER_MODE.
+ */
+struct bitland_profile_mode_map {
+	u8 balanced;
+	u8 performance;
+	u8 quiet;
+	u8 full_speed;
+};
+
+static const struct bitland_profile_mode_map bitland_mode_map = {
+	.balanced	= WMI_PP_BALANCED,
+	.performance	= WMI_PP_PERFORMANCE,
+	.quiet		= WMI_PP_QUIET,
+	.full_speed	= WMI_PP_FULL_SPEED,
+};
+
+static int bitland_pp_check_capability(struct bitland_mifs_wmi_data *data);
+
+/*
+ * Machine-specific operations. The MIFS WMI interface is shared by
+ * several Bitland ODM laptops which differ in the layout of the
+ * performance mode values and in the capability checks.
+ */
+struct bitland_mifs_ops {
+	const char *name;
+	const struct bitland_profile_mode_map *mode_map;
+	int (*check_performance_capability)(struct bitland_mifs_wmi_data *data);
+	bool has_full_speed;
+};
+
+static const struct bitland_mifs_ops bitland_ops = {
+	.name = "Bitland",
+	.mode_map = &bitland_mode_map,
+	.check_performance_capability = bitland_pp_check_capability,
+	.has_full_speed = true,
+};
+
+static const struct dmi_system_id bitland_mifs_dmi_table[] = {
+	{}
+};
+
 enum bitland_mifs_event_id {
 	WMI_EVENT_RESERVED_1		= 1,
 	WMI_EVENT_RESERVED_2		= 2,
@@ -165,6 +210,7 @@ struct bitland_mifs_wmi_data {
 	struct input_dev *input_dev;
 	struct device *hwmon_dev;
 	struct device *pp_dev;
+	const struct bitland_mifs_ops *ops;
 	enum platform_profile_option saved_profile;
 };
 
@@ -207,37 +253,35 @@ static int laptop_profile_get(struct device *dev,
 			      enum platform_profile_option *profile)
 {
 	struct bitland_mifs_wmi_data *data = dev_get_drvdata(dev);
+	const struct bitland_profile_mode_map *map = data->ops->mode_map;
 	struct bitland_mifs_input input = {
 		.operation = cpu_to_le16(WMI_METHOD_GET),
 		.function = cpu_to_le16(WMI_FN_SYSTEM_PER_MODE),
 	};
 	struct bitland_mifs_output result;
+	u8 mode;
 	int ret;
 
 	ret = bitland_mifs_wmi_call(data, &input, &result);
 	if (ret)
 		return ret;
 
-	switch (result.data[0]) {
-	case WMI_PP_BALANCED:
+	mode = result.data[0];
+	if (mode == map->quiet)
+		*profile = PLATFORM_PROFILE_LOW_POWER;
+	else if (mode == map->balanced)
 		*profile = PLATFORM_PROFILE_BALANCED;
-		break;
-	case WMI_PP_PERFORMANCE:
+	else if (mode == map->performance)
 		*profile = PLATFORM_PROFILE_BALANCED_PERFORMANCE;
-		break;
-	case WMI_PP_QUIET:
-		*profile = PLATFORM_PROFILE_LOW_POWER;
-		break;
-	case WMI_PP_FULL_SPEED:
+	else if (mode == map->full_speed)
 		*profile = PLATFORM_PROFILE_PERFORMANCE;
-		break;
-	default:
+	else
 		return -EINVAL;
-	}
+
 	return 0;
 }
 
-static int bitland_check_performance_capability(struct bitland_mifs_wmi_data *data)
+static int bitland_pp_check_capability(struct bitland_mifs_wmi_data *data)
 {
 	struct bitland_mifs_input input = {
 		.operation = cpu_to_le16(WMI_METHOD_GET),
@@ -268,47 +312,52 @@ static int laptop_profile_set(struct device *dev,
 			      enum platform_profile_option profile)
 {
 	struct bitland_mifs_wmi_data *data = dev_get_drvdata(dev);
+	const struct bitland_profile_mode_map *map = data->ops->mode_map;
 	struct bitland_mifs_input input = {
 		.operation = cpu_to_le16(WMI_METHOD_SET),
 		.function = cpu_to_le16(WMI_FN_SYSTEM_PER_MODE),
 	};
 	int ret;
-	u8 val;
+	u8 mode;
 
 	switch (profile) {
 	case PLATFORM_PROFILE_LOW_POWER:
-		val = WMI_PP_QUIET;
+		mode = map->quiet;
 		break;
 	case PLATFORM_PROFILE_BALANCED:
-		val = WMI_PP_BALANCED;
+		mode = map->balanced;
 		break;
 	case PLATFORM_PROFILE_BALANCED_PERFORMANCE:
-		ret = bitland_check_performance_capability(data);
+		ret = data->ops->check_performance_capability(data);
 		if (ret)
 			return ret;
-		val = WMI_PP_PERFORMANCE;
+		mode = map->performance;
 		break;
 	case PLATFORM_PROFILE_PERFORMANCE:
-		ret = bitland_check_performance_capability(data);
+		ret = data->ops->check_performance_capability(data);
 		if (ret)
 			return ret;
-		val = WMI_PP_FULL_SPEED;
+		mode = map->full_speed;
 		break;
 	default:
 		return -EOPNOTSUPP;
 	}
 
-	input.payload[0] = val;
+	input.payload[0] = mode;
 
 	return bitland_mifs_wmi_call(data, &input, NULL);
 }
 
 static int platform_profile_probe(void *drvdata, unsigned long *choices)
 {
+	struct bitland_mifs_wmi_data *data = drvdata;
+
 	set_bit(PLATFORM_PROFILE_LOW_POWER, choices);
 	set_bit(PLATFORM_PROFILE_BALANCED, choices);
 	set_bit(PLATFORM_PROFILE_BALANCED_PERFORMANCE, choices);
-	set_bit(PLATFORM_PROFILE_PERFORMANCE, choices);
+
+	if (data->ops->has_full_speed)
+		set_bit(PLATFORM_PROFILE_PERFORMANCE, choices);
 
 	return 0;
 }
@@ -706,6 +755,19 @@ static int bitland_notifier_callback(struct notifier_block *nb,
 	return NOTIFY_OK;
 }
 
+static void bitland_detect_ops(struct bitland_mifs_wmi_data *data)
+{
+	const struct dmi_system_id *id;
+
+	id = dmi_first_match(bitland_mifs_dmi_table);
+	if (id)
+		data->ops = id->driver_data;
+	else
+		data->ops = &bitland_ops;
+
+	dev_dbg(&data->wdev->dev, "Detected machine ops: %s\n", data->ops->name);
+}
+
 static int bitland_mifs_wmi_probe(struct wmi_device *wdev, const void *context)
 {
 	struct bitland_mifs_wmi_data *drv_data;
@@ -730,6 +792,8 @@ static int bitland_mifs_wmi_probe(struct wmi_device *wdev, const void *context)
 
 	dev_set_drvdata(&wdev->dev, drv_data);
 
+	bitland_detect_ops(drv_data);
+
 	if (dev_type == BITLAND_WMI_EVENT) {
 		/* Register input device for hotkeys */
 		drv_data->input_dev = devm_input_allocate_device(&wdev->dev);
-- 
2.55.0