[PATCH v5 0/1] asus-wmi: Add support for custom fan curves

[PATCH v5 0/1] asus-wmi: Add support for custom fan curves

[Luke D. Jones]

Add support for custom fan curves found on some ASUS ROG laptops.

The patch has gone through a few revisions as others tested it and
requested bahaviour changes or reported issues. V4 should be considered
finalised for now and I won't submit a new version until V4 has been
reviewed.

- V1
  + Initial patch work
- V2
  + Don't fail and remove wmi driver if error from
    asus_wmi_evaluate_method_buf() if error is -ENODEV
- V3
  + Store the "default" fan curves
  + Call throttle_thermal_policy_write() if a curve is erased to ensure
    that the factory default for a profile is applied again
- V4
  + Do not apply default curves by default. Testers have found that the
    default curves don't quite match actual no-curve behaviours
  + Add method to enable/disable curves for each profile
- V5
  + Remove an unrequired function left over from previous iterations
  + Ensure default curves are applied if user writes " " to a curve path
  + Rename "active_fan_curve_profiles" to "enabled_fan_curve_profiles" to
    better reflect the behavious of this setting
  + Move throttle_thermal_policy_write_*pu_curves() and rename to
    fan_curve_*pu_write()
  + Merge fan_curve_check_valid() and fan_curve_write()
  + Remove some leftover debug statements
  + Remove '\n' causing double-up of '\n\n'

Luke D. Jones (1):
  asus-wmi: Add support for custom fan curves

 drivers/platform/x86/asus-wmi.c            | 618 ++++++++++++++++++++-
 include/linux/platform_data/x86/asus-wmi.h |   2 +
 2 files changed, 619 insertions(+), 1 deletion(-)

--
2.31.1

[PATCH v5] asus-wmi: Add support for custom fan curves

[Luke D. Jones]

Add support for custom fan curves found on some ASUS ROG laptops.

These laptops have the ability to set a custom curve for the CPU
and GPU fans via an ACPI method call. This patch enables this,
additionally enabling custom fan curves per-profile, where profile
here means each of the 3 levels of "throttle_thermal_policy".

Signed-off-by: Luke D. Jones <luke@ljones.dev>
---
 drivers/platform/x86/asus-wmi.c            | 616 ++++++++++++++++++++-
 include/linux/platform_data/x86/asus-wmi.h |   2 +
 2 files changed, 616 insertions(+), 2 deletions(-)

diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c
index cc5811844012..944644ae0acd 100644
--- a/drivers/platform/x86/asus-wmi.c
+++ b/drivers/platform/x86/asus-wmi.c
@@ -108,6 +108,11 @@ module_param(fnlock_default, bool, 0444);
 
 static const char * const ashs_ids[] = { "ATK4001", "ATK4002", NULL };
 
+static int throttle_thermal_policy_write(struct asus_wmi*);
+static ssize_t fan_curve_store(struct asus_wmi *asus, const char *buf,
+								size_t count, u32 dev, char **curve,
+								char *default_curve);
+
 static bool ashs_present(void)
 {
 	int i = 0;
@@ -122,7 +127,8 @@ struct bios_args {
 	u32 arg0;
 	u32 arg1;
 	u32 arg2; /* At least TUF Gaming series uses 3 dword input buffer. */
-	u32 arg4;
+	u32 arg3;
+	u32 arg4; /* Some ROG laptops require a full 5 input args */
 	u32 arg5;
 } __packed;
 
@@ -173,6 +179,21 @@ enum fan_type {
 	FAN_TYPE_SPEC83,	/* starting in Spec 8.3, use CPU_FAN_CTRL */
 };
 
+struct fan_curve {
+	char *balanced;
+	char *balanced_default;
+	char *performance;
+	char *performance_default;
+	char *quiet;
+	char *quiet_default;
+};
+
+struct enabled_fan_curves {
+	bool balanced;
+	bool performance;
+	bool quiet;
+};
+
 struct asus_wmi {
 	int dsts_id;
 	int spec;
@@ -220,6 +241,14 @@ struct asus_wmi {
 	bool throttle_thermal_policy_available;
 	u8 throttle_thermal_policy_mode;
 
+	bool cpu_fan_curve_available;
+	struct fan_curve cpu_fan_curve;
+
+    bool gpu_fan_curve_available;
+	struct fan_curve gpu_fan_curve;
+
+	struct enabled_fan_curves enabled_fan_curve_profiles;
+
 	struct platform_profile_handler platform_profile_handler;
 	bool platform_profile_support;
 
@@ -285,6 +314,85 @@ int asus_wmi_evaluate_method(u32 method_id, u32 arg0, u32 arg1, u32 *retval)
 }
 EXPORT_SYMBOL_GPL(asus_wmi_evaluate_method);
 
+static int asus_wmi_evaluate_method5(u32 method_id,
+		u32 arg0, u32 arg1, u32 arg2, u32 arg3, u32 arg4, u32 *retval)
+{
+	struct bios_args args = {
+		.arg0 = arg0,
+		.arg1 = arg1,
+		.arg2 = arg2,
+		.arg3 = arg3,
+		.arg4 = arg4,
+	};
+	struct acpi_buffer input = { (acpi_size) sizeof(args), &args };
+	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
+	acpi_status status;
+	union acpi_object *obj;
+	u32 tmp = 0;
+
+	status = wmi_evaluate_method(ASUS_WMI_MGMT_GUID, 0, method_id,
+				     &input, &output);
+
+	if (ACPI_FAILURE(status))
+		return -EIO;
+
+	obj = (union acpi_object *)output.pointer;
+	if (obj && obj->type == ACPI_TYPE_INTEGER)
+		tmp = (u32) obj->integer.value;
+
+	if (retval)
+		*retval = tmp;
+
+	kfree(obj);
+
+	if (tmp == ASUS_WMI_UNSUPPORTED_METHOD)
+		return -ENODEV;
+
+	return 0;
+}
+
+/*
+ * Returns as an error if the method output is not a buffer. Typically this
+ * means that the method called is unsupported.
+*/
+static int asus_wmi_evaluate_method_buf(u32 method_id,
+		u32 arg0, u32 arg1, u8 *ret_buffer)
+{
+	struct bios_args args = {
+		.arg0 = arg0,
+		.arg1 = arg1,
+		.arg2 = 0,
+	};
+	struct acpi_buffer input = { (acpi_size) sizeof(args), &args };
+	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
+	acpi_status status;
+	union acpi_object *obj;
+	u32 int_tmp = 0;
+
+	status = wmi_evaluate_method(ASUS_WMI_MGMT_GUID, 0, method_id,
+				     &input, &output);
+
+	if (ACPI_FAILURE(status))
+		return -EIO;
+
+	obj = (union acpi_object *)output.pointer;
+
+	if (obj && obj->type == ACPI_TYPE_INTEGER) {
+		int_tmp = (u32) obj->integer.value;
+		if (int_tmp == ASUS_WMI_UNSUPPORTED_METHOD)
+			return -ENODEV;
+		return int_tmp;
+	}
+
+	if (obj && obj->type == ACPI_TYPE_BUFFER) {
+		memcpy(ret_buffer, obj->buffer.pointer, obj->buffer.length);
+	}
+
+	kfree(obj);
+
+	return 0;
+}
+
 static int asus_wmi_evaluate_method_agfn(const struct acpi_buffer args)
 {
 	struct acpi_buffer input;
@@ -1813,7 +1921,7 @@ static ssize_t fan1_label_show(struct device *dev,
 					  struct device_attribute *attr,
 					  char *buf)
 {
-	return sprintf(buf, "%s\n", ASUS_FAN_DESC);
+	return sprintf(buf, "%s", ASUS_FAN_DESC);
 }
 
 static ssize_t asus_hwmon_temp1(struct device *dev,
@@ -2043,6 +2151,458 @@ static ssize_t fan_boost_mode_store(struct device *dev,
 // Fan boost mode: 0 - normal, 1 - overboost, 2 - silent
 static DEVICE_ATTR_RW(fan_boost_mode);
 
+/* Custom fan curves per-profile **********************************************/
+
+/*
+ * Check if the ability to set fan curves on either fan exists, and store the
+ * defaults for recall later plus to provide users with a starting point.
+ *
+ * "dev" is either CPU_FAN_CURVE or GPU_FAN_CURVE.
+*/
+static int custom_fan_check_present(struct asus_wmi *asus,
+									bool *available, u32 dev)
+{
+	struct fan_curve *curves = &asus->cpu_fan_curve;
+	u8 *buf = kzalloc(16 * sizeof(u8), GFP_KERNEL);
+	/* 15 punctuation marks + 16 sets of numbers up to 3 char each */
+	int str_len = 15 + 16 * 3;
+	int err;
+
+	*available = false;
+
+	if (dev == ASUS_WMI_DEVID_GPU_FAN_CURVE)
+		curves = &asus->gpu_fan_curve;
+
+	/* Balanced default */
+	err = asus_wmi_evaluate_method_buf(asus->dsts_id, dev, 0, buf);
+	if (err) {
+		if (err == -ENODEV)
+			return 0;
+		return err;
+	}
+
+	curves->balanced = kzalloc(str_len * sizeof(char), GFP_KERNEL);
+	if (!curves->balanced)
+		return -ENOMEM;
+
+	curves->balanced_default = kzalloc(str_len * sizeof(char), GFP_KERNEL);
+	if (!curves->balanced_default)
+		return -ENOMEM;
+
+	sprintf(curves->balanced, "%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d",
+		buf[0], buf[8], buf[1], buf[9], buf[2], buf[10], buf[3], buf[11],
+		buf[4], buf[12], buf[5], buf[13], buf[6], buf[14], buf[7], buf[15]);
+	sprintf(curves->balanced_default, curves->balanced);
+
+	/* Quiet default */
+	err = asus_wmi_evaluate_method_buf(asus->dsts_id, dev, 1, buf);
+	if (err) {
+		if (err == -ENODEV)
+			return 0;
+		return err;
+	}
+
+	curves->quiet = kzalloc(str_len * sizeof(char), GFP_KERNEL);
+	if (!curves->quiet)
+		return -ENOMEM;
+
+	curves->quiet_default = kzalloc(str_len * sizeof(char), GFP_KERNEL);
+	if (!curves->quiet_default)
+		return -ENOMEM;
+
+	sprintf(curves->quiet, "%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d",
+		buf[0], buf[8], buf[1], buf[9], buf[2], buf[10], buf[3], buf[11],
+		buf[4], buf[12], buf[5], buf[13], buf[6], buf[14], buf[7], buf[15]);
+	sprintf(curves->quiet_default, curves->quiet);
+
+	/* Performance default */
+	err = asus_wmi_evaluate_method_buf(asus->dsts_id, dev, 2, buf);
+	if (err) {
+		if (err == -ENODEV)
+			return 0;
+		return err;
+	}
+
+	curves->performance = kzalloc(str_len * sizeof(char), GFP_KERNEL);
+	if (!curves->performance)
+		return -ENOMEM;
+
+	curves->performance_default = kzalloc(str_len * sizeof(char), GFP_KERNEL);
+	if (!curves->performance_default)
+		return -ENOMEM;
+
+	sprintf(curves->performance,
+		"%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d",
+		buf[0], buf[8], buf[1], buf[9], buf[2], buf[10], buf[3], buf[11],
+		buf[4], buf[12], buf[5], buf[13], buf[6], buf[14], buf[7], buf[15]);
+	sprintf(curves->performance_default, curves->performance);
+
+	kfree(buf);
+
+	*available = true;
+	return 0;
+}
+
+/*
+ * The expected input is of the format
+ *     "30:1,49:2,59:3,69:4,79:31,89:49,99:56,109:58"
+ * where a pair is 30:1, with 30 = temperature, and 1 = percentage
+*/
+static int fan_curve_write(struct asus_wmi *asus, u32 dev, char *curve)
+{
+    char * buf, *set, *pair_tmp, *pair, *set_end, *pair_end;
+    int err, ret;
+
+	char *set_delimiter = ",";
+	char *pair_delimiter = ":";
+	bool half_complete = false;
+	bool pair_start = true;
+	u32 prev_percent = 0;
+	u32 prev_temp = 0;
+	u32 percent = 0;
+	u32 shift = 0;
+	u32 temp = 0;
+    u32 arg1 = 0;
+    u32 arg2 = 0;
+    u32 arg3 = 0;
+    u32 arg4 = 0;
+
+    buf = set_end = pair_end = kstrdup(curve, GFP_KERNEL);
+
+	while( (set = strsep(&set_end, set_delimiter)) != NULL ) {
+		pair_tmp = kstrdup(set, GFP_KERNEL);
+        pair_start = true;
+		while( (pair = strsep(&pair_tmp, pair_delimiter)) != NULL ) {
+			err = kstrtouint(pair, 10, &ret);
+            if (err) {
+                kfree(pair_tmp);
+                kfree(buf);
+                return err;
+            }
+
+            if (pair_start) {
+                temp = ret;
+                pair_start = false;
+            } else {
+                percent = ret;
+            }
+		}
+		kfree(pair_tmp);
+
+		if (temp < prev_temp || percent < prev_percent || percent > 100) {
+            pr_info("Fan curve invalid");
+			pr_info("A value is sequentially lower or percentage is > 100");
+            kfree(buf);
+            return -EINVAL;
+        }
+
+        prev_temp = temp;
+        prev_percent = percent;
+
+        if (!half_complete) {
+            arg1 += temp << shift;
+            arg3 += percent << shift;
+        } else {
+            arg2 += temp << shift;
+            arg4 += percent << shift;
+        }
+        shift += 8;
+
+        if (shift == 32) {
+            shift = 0;
+            half_complete = true;
+        }
+	}
+	kfree(buf);
+
+    return asus_wmi_evaluate_method5(ASUS_WMI_METHODID_DEVS, dev,
+									 arg1, arg2, arg3, arg4, &ret);
+}
+
+static int fan_curve_cpu_write(struct asus_wmi *asus)
+{
+	char *curve = NULL;
+	int err, mode;
+
+	mode = asus->throttle_thermal_policy_mode;
+
+	if (mode == ASUS_THROTTLE_THERMAL_POLICY_DEFAULT
+					&& asus->enabled_fan_curve_profiles.balanced) {
+		curve = asus->cpu_fan_curve.balanced;
+	} else if (mode == ASUS_THROTTLE_THERMAL_POLICY_OVERBOOST
+					&& asus->enabled_fan_curve_profiles.performance) {
+		curve = asus->cpu_fan_curve.performance;
+	} else if (mode == ASUS_THROTTLE_THERMAL_POLICY_SILENT
+					&& asus->enabled_fan_curve_profiles.quiet) {
+		curve = asus->cpu_fan_curve.quiet;
+	}
+
+	if (curve != NULL) {
+		err = fan_curve_write(asus, ASUS_WMI_DEVID_CPU_FAN_CURVE, curve);
+		if (err)
+			return err;
+	}
+	return 0;
+}
+
+
+static int fan_curve_gpu_write(struct asus_wmi *asus)
+{
+	char *curve = NULL;
+	int err, mode;
+
+	mode = asus->throttle_thermal_policy_mode;
+
+	if (mode == ASUS_THROTTLE_THERMAL_POLICY_DEFAULT
+					&& asus->enabled_fan_curve_profiles.balanced) {
+		curve = asus->gpu_fan_curve.balanced;
+	} else if (mode == ASUS_THROTTLE_THERMAL_POLICY_OVERBOOST
+					&& asus->enabled_fan_curve_profiles.performance) {
+		curve = asus->gpu_fan_curve.performance;
+	} else if (mode == ASUS_THROTTLE_THERMAL_POLICY_SILENT
+					&& asus->enabled_fan_curve_profiles.quiet) {
+		curve = asus->gpu_fan_curve.quiet;
+	}
+
+	if (curve != NULL) {
+		err = fan_curve_write(asus, ASUS_WMI_DEVID_GPU_FAN_CURVE, curve);
+		if (err)
+			return err;
+	}
+	return 0;
+}
+
+static ssize_t fan_curve_store(struct asus_wmi *asus, const char *buf,
+								size_t count, u32 dev, char **curve,
+								char *default_curve)
+{
+    int err;
+
+	/* Allow a user to write "" or " " to erase a curve setting */
+	if (strlen(buf) <= 1 || strcmp(buf, " \n") == 0) {
+		kfree(*curve);
+		*curve = kstrdup(default_curve, GFP_KERNEL);
+		err = throttle_thermal_policy_write(asus);
+		if (err)
+			return err;
+		return count;
+	}
+
+	if (*curve)
+		kfree(*curve);
+    *curve = kstrdup(buf, GFP_KERNEL);
+
+	/* Maybe activate fan curve if in associated mode */
+	err = throttle_thermal_policy_write(asus);
+	if (err) {
+		kfree(*curve);
+		*curve = kstrdup(default_curve, GFP_KERNEL);
+		return err;
+	}
+
+    return count;
+}
+
+/*
+ * CPU Fan Curves
+*/
+
+static ssize_t cpu_fan_curve_balanced_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct asus_wmi *asus = dev_get_drvdata(dev);
+	return scnprintf(buf, PAGE_SIZE, "%s", asus->cpu_fan_curve.balanced);
+}
+
+static ssize_t cpu_fan_curve_balanced_store(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *buf, size_t count)
+{
+    struct asus_wmi *asus = dev_get_drvdata(dev);
+    return fan_curve_store(asus, buf, count, ASUS_WMI_DEVID_CPU_FAN_CURVE,
+							&asus->cpu_fan_curve.balanced,
+							asus->cpu_fan_curve.balanced_default);
+}
+
+static DEVICE_ATTR_RW(cpu_fan_curve_balanced);
+
+static ssize_t cpu_fan_curve_performance_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct asus_wmi *asus = dev_get_drvdata(dev);
+	return scnprintf(buf, PAGE_SIZE, "%s", asus->cpu_fan_curve.performance);
+}
+
+static ssize_t cpu_fan_curve_performance_store(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *buf, size_t count)
+{
+    struct asus_wmi *asus = dev_get_drvdata(dev);
+    return fan_curve_store(asus, buf, count, ASUS_WMI_DEVID_CPU_FAN_CURVE,
+							&asus->cpu_fan_curve.performance,
+							asus->cpu_fan_curve.performance_default);
+}
+
+static DEVICE_ATTR_RW(cpu_fan_curve_performance);
+
+static ssize_t cpu_fan_curve_quiet_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct asus_wmi *asus = dev_get_drvdata(dev);
+	return scnprintf(buf, PAGE_SIZE, "%s", asus->cpu_fan_curve.quiet);
+}
+
+static ssize_t cpu_fan_curve_quiet_store(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *buf, size_t count)
+{
+    struct asus_wmi *asus = dev_get_drvdata(dev);
+    return fan_curve_store(asus, buf, count, ASUS_WMI_DEVID_CPU_FAN_CURVE,
+							&asus->cpu_fan_curve.quiet,
+							asus->cpu_fan_curve.quiet_default);
+}
+
+static DEVICE_ATTR_RW(cpu_fan_curve_quiet);
+
+/*
+ * GPU Fan Curves
+*/
+
+static ssize_t gpu_fan_curve_balanced_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct asus_wmi *asus = dev_get_drvdata(dev);
+	return scnprintf(buf, PAGE_SIZE, "%s", asus->gpu_fan_curve.balanced);
+}
+
+static ssize_t gpu_fan_curve_balanced_store(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *buf, size_t count)
+{
+    struct asus_wmi *asus = dev_get_drvdata(dev);
+    return fan_curve_store(asus, buf, count, ASUS_WMI_DEVID_GPU_FAN_CURVE,
+							&asus->gpu_fan_curve.balanced,
+							asus->gpu_fan_curve.balanced_default);
+}
+
+static DEVICE_ATTR_RW(gpu_fan_curve_balanced);
+
+static ssize_t gpu_fan_curve_performance_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct asus_wmi *asus = dev_get_drvdata(dev);
+	return scnprintf(buf, PAGE_SIZE, "%s", asus->gpu_fan_curve.performance);
+}
+
+static ssize_t gpu_fan_curve_performance_store(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *buf, size_t count)
+{
+    struct asus_wmi *asus = dev_get_drvdata(dev);
+    return fan_curve_store(asus, buf, count, ASUS_WMI_DEVID_GPU_FAN_CURVE,
+							&asus->gpu_fan_curve.performance,
+							asus->gpu_fan_curve.performance_default);
+}
+
+static DEVICE_ATTR_RW(gpu_fan_curve_performance);
+
+static ssize_t gpu_fan_curve_quiet_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct asus_wmi *asus = dev_get_drvdata(dev);
+	return scnprintf(buf, PAGE_SIZE, "%s", asus->gpu_fan_curve.quiet);
+}
+
+static ssize_t gpu_fan_curve_quiet_store(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *buf, size_t count)
+{
+    struct asus_wmi *asus = dev_get_drvdata(dev);
+    return fan_curve_store(asus, buf, count, ASUS_WMI_DEVID_GPU_FAN_CURVE,
+							&asus->gpu_fan_curve.quiet,
+							asus->gpu_fan_curve.quiet_default);
+}
+
+static DEVICE_ATTR_RW(gpu_fan_curve_quiet);
+
+/*
+ * Profiles with enabled fan curve setting
+*/
+
+static int enabled_fan_curve_profiles_write(struct asus_wmi *asus,
+											const char *names)
+{
+    char *buf, *set, *set_end;
+    int err;
+
+    buf = set_end = kstrdup(names, GFP_KERNEL);
+
+	/* Reset before checking */
+	asus->enabled_fan_curve_profiles.balanced = false;
+	asus->enabled_fan_curve_profiles.quiet = false;
+	asus->enabled_fan_curve_profiles.performance = false;
+
+	while( (set = strsep(&set_end, " ")) != NULL ) {
+		if (set == NULL)
+			set = buf;
+
+		if (strcmp(set, "balanced") == 0
+				|| strcmp(set, "balanced\n") == 0)
+			asus->enabled_fan_curve_profiles.balanced = true;
+
+		if (strcmp(set, "quiet") == 0
+				|| strcmp(set, "quiet\n") == 0)
+			asus->enabled_fan_curve_profiles.quiet = true;
+
+		if (strcmp(set, "performance") == 0
+				|| strcmp(set, "performance\n") == 0)
+			asus->enabled_fan_curve_profiles.performance = true;
+	}
+
+	err = throttle_thermal_policy_write(asus);
+	if (err)
+		return err;
+
+	kfree(buf);
+
+	return 0;
+}
+
+static ssize_t enabled_fan_curve_profiles_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct asus_wmi *asus = dev_get_drvdata(dev);
+	int len = 0;
+
+	if (asus->enabled_fan_curve_profiles.balanced)
+		len += sysfs_emit_at(buf, len, "balanced ");
+
+	if (asus->enabled_fan_curve_profiles.performance)
+		len += sysfs_emit_at(buf, len, "performance ");
+
+	if (asus->enabled_fan_curve_profiles.quiet)
+		len += sysfs_emit_at(buf, len, "quiet ");
+
+	len += sysfs_emit_at(buf, len, "\n");
+	return len;
+}
+
+static ssize_t enabled_fan_curve_profiles_store(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *buf, size_t count)
+{
+    struct asus_wmi *asus = dev_get_drvdata(dev);
+	int err;
+
+	err = enabled_fan_curve_profiles_write(asus, buf);
+	if (err)
+		return err;
+
+    return count;
+}
+
+static DEVICE_ATTR_RW(enabled_fan_curve_profiles);
+
 /* Throttle thermal policy ****************************************************/
 
 static int throttle_thermal_policy_check_present(struct asus_wmi *asus)
@@ -2092,6 +2652,26 @@ static int throttle_thermal_policy_write(struct asus_wmi *asus)
 		return -EIO;
 	}
 
+	if (asus->cpu_fan_curve_available) {
+		err = fan_curve_cpu_write(asus);
+		if (err) {
+			dev_warn(&asus->platform_device->dev,
+				"Failed to set custom CPU curve for thermal policy: %d\n",
+				err);
+			return err;
+		}
+	}
+
+	if (asus->gpu_fan_curve_available) {
+		err = fan_curve_gpu_write(asus);
+		if (err) {
+			dev_warn(&asus->platform_device->dev,
+				"Failed to set custom GPU curve for thermal policy: %d\n",
+				err);
+			return err;
+		}
+	}
+
 	return 0;
 }
 
@@ -2711,6 +3291,13 @@ static struct attribute *platform_attributes[] = {
 	&dev_attr_als_enable.attr,
 	&dev_attr_fan_boost_mode.attr,
 	&dev_attr_throttle_thermal_policy.attr,
+	&dev_attr_cpu_fan_curve_balanced.attr,
+	&dev_attr_cpu_fan_curve_performance.attr,
+	&dev_attr_cpu_fan_curve_quiet.attr,
+    &dev_attr_gpu_fan_curve_balanced.attr,
+	&dev_attr_gpu_fan_curve_performance.attr,
+	&dev_attr_gpu_fan_curve_quiet.attr,
+	&dev_attr_enabled_fan_curve_profiles.attr,
 	&dev_attr_panel_od.attr,
 	NULL
 };
@@ -2741,6 +3328,20 @@ static umode_t asus_sysfs_is_visible(struct kobject *kobj,
 		ok = asus->fan_boost_mode_available;
 	else if (attr == &dev_attr_throttle_thermal_policy.attr)
 		ok = asus->throttle_thermal_policy_available;
+	else if (attr == &dev_attr_cpu_fan_curve_balanced.attr)
+		ok = asus->cpu_fan_curve_available;
+	else if (attr == &dev_attr_cpu_fan_curve_performance.attr)
+		ok = asus->cpu_fan_curve_available;
+	else if (attr == &dev_attr_cpu_fan_curve_quiet.attr)
+		ok = asus->cpu_fan_curve_available;
+    else if (attr == &dev_attr_gpu_fan_curve_balanced.attr)
+		ok = asus->gpu_fan_curve_available;
+	else if (attr == &dev_attr_gpu_fan_curve_performance.attr)
+		ok = asus->gpu_fan_curve_available;
+	else if (attr == &dev_attr_gpu_fan_curve_quiet.attr)
+		ok = asus->gpu_fan_curve_available;
+	else if (attr == &dev_attr_enabled_fan_curve_profiles.attr)
+		ok = asus->cpu_fan_curve_available || asus->gpu_fan_curve_available;
 	else if (attr == &dev_attr_panel_od.attr)
 		ok = asus->panel_overdrive_available;
 
@@ -3016,6 +3617,16 @@ static int asus_wmi_add(struct platform_device *pdev)
 	else
 		throttle_thermal_policy_set_default(asus);
 
+	err = custom_fan_check_present(asus, &asus->cpu_fan_curve_available,
+			ASUS_WMI_DEVID_CPU_FAN_CURVE);
+	if (err)
+		goto fail_custom_fan_curve;
+
+    err = custom_fan_check_present(asus, &asus->gpu_fan_curve_available,
+			ASUS_WMI_DEVID_GPU_FAN_CURVE);
+	if (err)
+		goto fail_custom_fan_curve;
+
 	err = platform_profile_setup(asus);
 	if (err)
 		goto fail_platform_profile_setup;
@@ -3109,6 +3720,7 @@ static int asus_wmi_add(struct platform_device *pdev)
 	asus_wmi_sysfs_exit(asus->platform_device);
 fail_sysfs:
 fail_throttle_thermal_policy:
+fail_custom_fan_curve:
 fail_platform_profile_setup:
 	if (asus->platform_profile_support)
 		platform_profile_remove();
diff --git a/include/linux/platform_data/x86/asus-wmi.h b/include/linux/platform_data/x86/asus-wmi.h
index 17dc5cb6f3f2..a571b47ff362 100644
--- a/include/linux/platform_data/x86/asus-wmi.h
+++ b/include/linux/platform_data/x86/asus-wmi.h
@@ -77,6 +77,8 @@
 #define ASUS_WMI_DEVID_THERMAL_CTRL	0x00110011
 #define ASUS_WMI_DEVID_FAN_CTRL		0x00110012 /* deprecated */
 #define ASUS_WMI_DEVID_CPU_FAN_CTRL	0x00110013
+#define ASUS_WMI_DEVID_CPU_FAN_CURVE	0x00110024
+#define ASUS_WMI_DEVID_GPU_FAN_CURVE	0x00110025
 
 /* Power */
 #define ASUS_WMI_DEVID_PROCESSOR_STATE	0x00120012
-- 
2.31.1

Re: [PATCH v5 0/1] asus-wmi: Add support for custom fan curves

[Luke Jones]

On Fri, Aug 27 2021 at 11:42:58 +1200, Luke D. Jones <luke@ljones.dev> 
wrote:
> Add support for custom fan curves found on some ASUS ROG laptops.
> 
> The patch has gone through a few revisions as others tested it and
> requested bahaviour changes or reported issues. V4 should be 
> considered
> finalised for now and I won't submit a new version until V4 has been
> reviewed.

Sorry, I copy/pasted my last log. This V5 is pretty much finalised now. 
Testing and self-review seems to have caught everything it possibly can.

Cheers,
Luke.

> - V1
>   + Initial patch work
> - V2
>   + Don't fail and remove wmi driver if error from
>     asus_wmi_evaluate_method_buf() if error is -ENODEV
> - V3
>   + Store the "default" fan curves
>   + Call throttle_thermal_policy_write() if a curve is erased to 
> ensure
>     that the factory default for a profile is applied again
> - V4
>   + Do not apply default curves by default. Testers have found that 
> the
>     default curves don't quite match actual no-curve behaviours
>   + Add method to enable/disable curves for each profile
> - V5
>   + Remove an unrequired function left over from previous iterations
>   + Ensure default curves are applied if user writes " " to a curve 
> path
>   + Rename "active_fan_curve_profiles" to 
> "enabled_fan_curve_profiles" to
>     better reflect the behavious of this setting
>   + Move throttle_thermal_policy_write_*pu_curves() and rename to
>     fan_curve_*pu_write()
>   + Merge fan_curve_check_valid() and fan_curve_write()
>   + Remove some leftover debug statements
>   + Remove '\n' causing double-up of '\n\n'
> 
> Luke D. Jones (1):
>   asus-wmi: Add support for custom fan curves
> 
>  drivers/platform/x86/asus-wmi.c            | 618 
> ++++++++++++++++++++-
>  include/linux/platform_data/x86/asus-wmi.h |   2 +
>  2 files changed, 619 insertions(+), 1 deletion(-)
> 
> --
> 2.31.1
> 

Re: [PATCH v5] asus-wmi: Add support for custom fan curves

[Barnabás Pőcze]

Hi


+CC Guenter Roeck as he may be able to tell us if there's an established
way to export fan curves.

I have added a couple comments.
There are places where spaces are used instead of tabs.


2021. augusztus 27., péntek 1:42 keltezéssel, Luke D. Jones írta:
> Add support for custom fan curves found on some ASUS ROG laptops.
>
> These laptops have the ability to set a custom curve for the CPU
> and GPU fans via an ACPI method call. This patch enables this,
> additionally enabling custom fan curves per-profile, where profile
> here means each of the 3 levels of "throttle_thermal_policy".
>
> Signed-off-by: Luke D. Jones <luke@ljones.dev>
> ---
>  drivers/platform/x86/asus-wmi.c            | 616 ++++++++++++++++++++-
>  include/linux/platform_data/x86/asus-wmi.h |   2 +
>  2 files changed, 616 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c
> index cc5811844012..944644ae0acd 100644
> --- a/drivers/platform/x86/asus-wmi.c
> +++ b/drivers/platform/x86/asus-wmi.c
> @@ -108,6 +108,11 @@ module_param(fnlock_default, bool, 0444);
>
>  static const char * const ashs_ids[] = { "ATK4001", "ATK4002", NULL };
>
> +static int throttle_thermal_policy_write(struct asus_wmi*);
> +static ssize_t fan_curve_store(struct asus_wmi *asus, const char *buf,
> +								size_t count, u32 dev, char **curve,
> +								char *default_curve);
> +
>  static bool ashs_present(void)
>  {
>  	int i = 0;
> @@ -122,7 +127,8 @@ struct bios_args {
>  	u32 arg0;
>  	u32 arg1;
>  	u32 arg2; /* At least TUF Gaming series uses 3 dword input buffer. */
> -	u32 arg4;
> +	u32 arg3;
> +	u32 arg4; /* Some ROG laptops require a full 5 input args */
>  	u32 arg5;
>  } __packed;
>
> @@ -173,6 +179,21 @@ enum fan_type {
>  	FAN_TYPE_SPEC83,	/* starting in Spec 8.3, use CPU_FAN_CTRL */
>  };
>
> +struct fan_curve {
> +	char *balanced;
> +	char *balanced_default;
> +	char *performance;
> +	char *performance_default;
> +	char *quiet;
> +	char *quiet_default;
> +};
> +
> +struct enabled_fan_curves {
> +	bool balanced;
> +	bool performance;
> +	bool quiet;
> +};
> +
>  struct asus_wmi {
>  	int dsts_id;
>  	int spec;
> @@ -220,6 +241,14 @@ struct asus_wmi {
>  	bool throttle_thermal_policy_available;
>  	u8 throttle_thermal_policy_mode;
>
> +	bool cpu_fan_curve_available;
> +	struct fan_curve cpu_fan_curve;
> +
> +    bool gpu_fan_curve_available;
> +	struct fan_curve gpu_fan_curve;
> +
> +	struct enabled_fan_curves enabled_fan_curve_profiles;

I would suggest something like the following:

  struct fan_curve {
    /* bool enabled; */
    u8 temps[FAN_CURVE_SIZE];
    u8 percents[FAN_CURVE_SIZE];
  };

  struct fan {
    bool available;
    struct fan_curve curves[NUM_PERF_PROFILES];
  };

  struct asus_wmi {
    ...

    struct fan fans[NUM_FANS];

    bool fan_curve_enabled_for_profile[NUM_PERF_PROFILES];
    /* or maybe you could add it as `bool enabled;` into the inner struct */
  };

see the reason later.


> +
>  	struct platform_profile_handler platform_profile_handler;
>  	bool platform_profile_support;
>
> @@ -285,6 +314,85 @@ int asus_wmi_evaluate_method(u32 method_id, u32 arg0, u32 arg1, u32 *retval)
>  }
>  EXPORT_SYMBOL_GPL(asus_wmi_evaluate_method);
>
> +static int asus_wmi_evaluate_method5(u32 method_id,
> +		u32 arg0, u32 arg1, u32 arg2, u32 arg3, u32 arg4, u32 *retval)
> +{
> +	struct bios_args args = {
> +		.arg0 = arg0,
> +		.arg1 = arg1,
> +		.arg2 = arg2,
> +		.arg3 = arg3,
> +		.arg4 = arg4,
> +	};
> +	struct acpi_buffer input = { (acpi_size) sizeof(args), &args };
> +	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
> +	acpi_status status;
> +	union acpi_object *obj;
> +	u32 tmp = 0;
> +
> +	status = wmi_evaluate_method(ASUS_WMI_MGMT_GUID, 0, method_id,
> +				     &input, &output);
> +
> +	if (ACPI_FAILURE(status))
> +		return -EIO;
> +
> +	obj = (union acpi_object *)output.pointer;

Small thing, but this cast is unnecessary.


> +	if (obj && obj->type == ACPI_TYPE_INTEGER)
> +		tmp = (u32) obj->integer.value;

Same here.


> +
> +	if (retval)
> +		*retval = tmp;
> +
> +	kfree(obj);
> +
> +	if (tmp == ASUS_WMI_UNSUPPORTED_METHOD)
> +		return -ENODEV;
> +
> +	return 0;
> +}
> +
> +/*
> + * Returns as an error if the method output is not a buffer. Typically this
> + * means that the method called is unsupported.
> +*/
> +static int asus_wmi_evaluate_method_buf(u32 method_id,
> +		u32 arg0, u32 arg1, u8 *ret_buffer)
> +{
> +	struct bios_args args = {
> +		.arg0 = arg0,
> +		.arg1 = arg1,
> +		.arg2 = 0,
> +	};
> +	struct acpi_buffer input = { (acpi_size) sizeof(args), &args };
> +	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
> +	acpi_status status;
> +	union acpi_object *obj;
> +	u32 int_tmp = 0;
> +
> +	status = wmi_evaluate_method(ASUS_WMI_MGMT_GUID, 0, method_id,
> +				     &input, &output);
> +
> +	if (ACPI_FAILURE(status))
> +		return -EIO;
> +
> +	obj = (union acpi_object *)output.pointer;
> +
> +	if (obj && obj->type == ACPI_TYPE_INTEGER) {
> +		int_tmp = (u32) obj->integer.value;
> +		if (int_tmp == ASUS_WMI_UNSUPPORTED_METHOD)
> +			return -ENODEV;
> +		return int_tmp;
> +	}
> +
> +	if (obj && obj->type == ACPI_TYPE_BUFFER) {
> +		memcpy(ret_buffer, obj->buffer.pointer, obj->buffer.length);
> +	}
> +
> +	kfree(obj);
> +
> +	return 0;
> +}
> +
>  static int asus_wmi_evaluate_method_agfn(const struct acpi_buffer args)
>  {
>  	struct acpi_buffer input;
> @@ -1813,7 +1921,7 @@ static ssize_t fan1_label_show(struct device *dev,
>  					  struct device_attribute *attr,
>  					  char *buf)
>  {
> -	return sprintf(buf, "%s\n", ASUS_FAN_DESC);
> +	return sprintf(buf, "%s", ASUS_FAN_DESC);

What is the reason for this change?


>  }
>
>  static ssize_t asus_hwmon_temp1(struct device *dev,
> @@ -2043,6 +2151,458 @@ static ssize_t fan_boost_mode_store(struct device *dev,
>  // Fan boost mode: 0 - normal, 1 - overboost, 2 - silent
>  static DEVICE_ATTR_RW(fan_boost_mode);
>
> +/* Custom fan curves per-profile **********************************************/
> +
> +/*
> + * Check if the ability to set fan curves on either fan exists, and store the
> + * defaults for recall later plus to provide users with a starting point.
> + *
> + * "dev" is either CPU_FAN_CURVE or GPU_FAN_CURVE.
> +*/
> +static int custom_fan_check_present(struct asus_wmi *asus,
> +									bool *available, u32 dev)
> +{
> +	struct fan_curve *curves = &asus->cpu_fan_curve;
> +	u8 *buf = kzalloc(16 * sizeof(u8), GFP_KERNEL);

Is dynamic allocation needed here? No early return frees it.


> +	/* 15 punctuation marks + 16 sets of numbers up to 3 char each */
> +	int str_len = 15 + 16 * 3;

It appears to me that the terminating null byte is not accounted for. E.g.:

  255:255,255:255,255:255,255:255,255:255,255:255,255:255,255:255

is itself already 63 (= 15 + 16 x 3) characters.

And if the maximum length is known, and it's reasonably small, why is it not
part of the struct as a char array? E.g.:

  struct fan_curve {
    char balanced[FAN_CURVE_STR_SIZE]; /* #define FAN_CURVE_STR_SIZE 64 */
    ...
  };

I would actually suggest storing the u8 array itself in the fan curve struct,
and not a string representation of it. I think the data is easier to deal with
that way, and the price of formatting it for the sysfs attribute is not
significant.


> +	int err;
> +
> +	*available = false;
> +
> +	if (dev == ASUS_WMI_DEVID_GPU_FAN_CURVE)
> +		curves = &asus->gpu_fan_curve;
> +
> +	/* Balanced default */
> +	err = asus_wmi_evaluate_method_buf(asus->dsts_id, dev, 0, buf);
> +	if (err) {
> +		if (err == -ENODEV)
> +			return 0;
> +		return err;
> +	}
> +
> +	curves->balanced = kzalloc(str_len * sizeof(char), GFP_KERNEL);
> +	if (!curves->balanced)
> +		return -ENOMEM;
> +
> +	curves->balanced_default = kzalloc(str_len * sizeof(char), GFP_KERNEL);
> +	if (!curves->balanced_default)
> +		return -ENOMEM;
> +
> +	sprintf(curves->balanced, "%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d",
> +		buf[0], buf[8], buf[1], buf[9], buf[2], buf[10], buf[3], buf[11],
> +		buf[4], buf[12], buf[5], buf[13], buf[6], buf[14], buf[7], buf[15]);
> +	sprintf(curves->balanced_default, curves->balanced);
> +
> +	/* Quiet default */
> +	err = asus_wmi_evaluate_method_buf(asus->dsts_id, dev, 1, buf);
> +	if (err) {
> +		if (err == -ENODEV)
> +			return 0;
> +		return err;
> +	}
> +
> +	curves->quiet = kzalloc(str_len * sizeof(char), GFP_KERNEL);
> +	if (!curves->quiet)
> +		return -ENOMEM;
> +
> +	curves->quiet_default = kzalloc(str_len * sizeof(char), GFP_KERNEL);
> +	if (!curves->quiet_default)
> +		return -ENOMEM;
> +
> +	sprintf(curves->quiet, "%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d",
> +		buf[0], buf[8], buf[1], buf[9], buf[2], buf[10], buf[3], buf[11],
> +		buf[4], buf[12], buf[5], buf[13], buf[6], buf[14], buf[7], buf[15]);
> +	sprintf(curves->quiet_default, curves->quiet);
> +
> +	/* Performance default */
> +	err = asus_wmi_evaluate_method_buf(asus->dsts_id, dev, 2, buf);
> +	if (err) {
> +		if (err == -ENODEV)
> +			return 0;
> +		return err;
> +	}
> +
> +	curves->performance = kzalloc(str_len * sizeof(char), GFP_KERNEL);
> +	if (!curves->performance)
> +		return -ENOMEM;
> +
> +	curves->performance_default = kzalloc(str_len * sizeof(char), GFP_KERNEL);
> +	if (!curves->performance_default)
> +		return -ENOMEM;
> +
> +	sprintf(curves->performance,
> +		"%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d",
> +		buf[0], buf[8], buf[1], buf[9], buf[2], buf[10], buf[3], buf[11],
> +		buf[4], buf[12], buf[5], buf[13], buf[6], buf[14], buf[7], buf[15]);
> +	sprintf(curves->performance_default, curves->performance);

More or less the same code is repeated three times, I'd consider adding an e.g.

  void fan_curve_to_str(..., char[static FAN_CURVE_STR_SIZE]);

function.


> +
> +	kfree(buf);
> +
> +	*available = true;
> +	return 0;
> +}
> +
> +/*
> + * The expected input is of the format
> + *     "30:1,49:2,59:3,69:4,79:31,89:49,99:56,109:58"
> + * where a pair is 30:1, with 30 = temperature, and 1 = percentage
> +*/
> +static int fan_curve_write(struct asus_wmi *asus, u32 dev, char *curve)
> +{
> +    char * buf, *set, *pair_tmp, *pair, *set_end, *pair_end;
> +    int err, ret;
> +
> +	char *set_delimiter = ",";
> +	char *pair_delimiter = ":";
> +	bool half_complete = false;
> +	bool pair_start = true;
> +	u32 prev_percent = 0;
> +	u32 prev_temp = 0;
> +	u32 percent = 0;
> +	u32 shift = 0;
> +	u32 temp = 0;
> +    u32 arg1 = 0;
> +    u32 arg2 = 0;
> +    u32 arg3 = 0;
> +    u32 arg4 = 0;
> +
> +    buf = set_end = pair_end = kstrdup(curve, GFP_KERNEL);
> +
> +	while( (set = strsep(&set_end, set_delimiter)) != NULL ) {
> +		pair_tmp = kstrdup(set, GFP_KERNEL);
> +        pair_start = true;
> +		while( (pair = strsep(&pair_tmp, pair_delimiter)) != NULL ) {
> +			err = kstrtouint(pair, 10, &ret);
> +            if (err) {
> +                kfree(pair_tmp);
> +                kfree(buf);
> +                return err;
> +            }
> +
> +            if (pair_start) {
> +                temp = ret;
> +                pair_start = false;
> +            } else {
> +                percent = ret;
> +            }
> +		}
> +		kfree(pair_tmp);
> +
> +		if (temp < prev_temp || percent < prev_percent || percent > 100) {
> +            pr_info("Fan curve invalid");
> +			pr_info("A value is sequentially lower or percentage is > 100");
> +            kfree(buf);
> +            return -EINVAL;
> +        }
> +
> +        prev_temp = temp;
> +        prev_percent = percent;
> +
> +        if (!half_complete) {
> +            arg1 += temp << shift;
> +            arg3 += percent << shift;
> +        } else {
> +            arg2 += temp << shift;
> +            arg4 += percent << shift;
> +        }

As far as I see using 64-bit integers would avoid the need for `half_complete`, et al.


> +        shift += 8;
> +
> +        if (shift == 32) {
> +            shift = 0;
> +            half_complete = true;
> +        }
> +	}
> +	kfree(buf);
> +

If you don't insist on using commas, I think it is much simpler to
parse it using `sscanf()`, e.g.:

  unsigned int temp, prct;
  int at = 0, len;

  while (sscanf(&buf[at], "%u:%u %n", &temp, &prct, &len) == 2) {
    /* process `temp` and `prct` */

    at += len;
  }

  if (buf[at] != '\0')
    /* error */;

This also has the advantage that you don't need dynamic memory allocation.


> +    return asus_wmi_evaluate_method5(ASUS_WMI_METHODID_DEVS, dev,
> +									 arg1, arg2, arg3, arg4, &ret);
> +}
> +
> +static int fan_curve_cpu_write(struct asus_wmi *asus)
> +{
> +	char *curve = NULL;
> +	int err, mode;
> +
> +	mode = asus->throttle_thermal_policy_mode;
> +
> +	if (mode == ASUS_THROTTLE_THERMAL_POLICY_DEFAULT
> +					&& asus->enabled_fan_curve_profiles.balanced) {
> +		curve = asus->cpu_fan_curve.balanced;
> +	} else if (mode == ASUS_THROTTLE_THERMAL_POLICY_OVERBOOST
> +					&& asus->enabled_fan_curve_profiles.performance) {
> +		curve = asus->cpu_fan_curve.performance;
> +	} else if (mode == ASUS_THROTTLE_THERMAL_POLICY_SILENT
> +					&& asus->enabled_fan_curve_profiles.quiet) {
> +		curve = asus->cpu_fan_curve.quiet;
> +	}
> +
> +	if (curve != NULL) {
> +		err = fan_curve_write(asus, ASUS_WMI_DEVID_CPU_FAN_CURVE, curve);
> +		if (err)
> +			return err;
> +	}
> +	return 0;
> +}
> +
> +
> +static int fan_curve_gpu_write(struct asus_wmi *asus)
> +{
> +	char *curve = NULL;
> +	int err, mode;
> +
> +	mode = asus->throttle_thermal_policy_mode;
> +
> +	if (mode == ASUS_THROTTLE_THERMAL_POLICY_DEFAULT
> +					&& asus->enabled_fan_curve_profiles.balanced) {
> +		curve = asus->gpu_fan_curve.balanced;
> +	} else if (mode == ASUS_THROTTLE_THERMAL_POLICY_OVERBOOST
> +					&& asus->enabled_fan_curve_profiles.performance) {
> +		curve = asus->gpu_fan_curve.performance;
> +	} else if (mode == ASUS_THROTTLE_THERMAL_POLICY_SILENT
> +					&& asus->enabled_fan_curve_profiles.quiet) {
> +		curve = asus->gpu_fan_curve.quiet;
> +	}
> +
> +	if (curve != NULL) {
> +		err = fan_curve_write(asus, ASUS_WMI_DEVID_GPU_FAN_CURVE, curve);
> +		if (err)
> +			return err;
> +	}
> +	return 0;
> +}
> +
> +static ssize_t fan_curve_store(struct asus_wmi *asus, const char *buf,
> +								size_t count, u32 dev, char **curve,
> +								char *default_curve)
> +{
> +    int err;
> +
> +	/* Allow a user to write "" or " " to erase a curve setting */
> +	if (strlen(buf) <= 1 || strcmp(buf, " \n") == 0) {
> +		kfree(*curve);
> +		*curve = kstrdup(default_curve, GFP_KERNEL);
> +		err = throttle_thermal_policy_write(asus);
> +		if (err)
> +			return err;
> +		return count;
> +	}
> +
> +	if (*curve)
> +		kfree(*curve);
> +    *curve = kstrdup(buf, GFP_KERNEL);
> +
> +	/* Maybe activate fan curve if in associated mode */
> +	err = throttle_thermal_policy_write(asus);
> +	if (err) {
> +		kfree(*curve);
> +		*curve = kstrdup(default_curve, GFP_KERNEL);
> +		return err;
> +	}
> +
> +    return count;
> +}
> +
> +/*
> + * CPU Fan Curves
> +*/
> +
> +static ssize_t cpu_fan_curve_balanced_show(struct device *dev,
> +				   struct device_attribute *attr, char *buf)
> +{
> +	struct asus_wmi *asus = dev_get_drvdata(dev);
> +	return scnprintf(buf, PAGE_SIZE, "%s", asus->cpu_fan_curve.balanced);
> +}
> +
> +static ssize_t cpu_fan_curve_balanced_store(struct device *dev,
> +				    struct device_attribute *attr,
> +				    const char *buf, size_t count)
> +{
> +    struct asus_wmi *asus = dev_get_drvdata(dev);
> +    return fan_curve_store(asus, buf, count, ASUS_WMI_DEVID_CPU_FAN_CURVE,
> +							&asus->cpu_fan_curve.balanced,
> +							asus->cpu_fan_curve.balanced_default);
> +}
> +
> +static DEVICE_ATTR_RW(cpu_fan_curve_balanced);
> +
> +static ssize_t cpu_fan_curve_performance_show(struct device *dev,
> +				   struct device_attribute *attr, char *buf)
> +{
> +	struct asus_wmi *asus = dev_get_drvdata(dev);
> +	return scnprintf(buf, PAGE_SIZE, "%s", asus->cpu_fan_curve.performance);
> +}
> +
> +static ssize_t cpu_fan_curve_performance_store(struct device *dev,
> +				    struct device_attribute *attr,
> +				    const char *buf, size_t count)
> +{
> +    struct asus_wmi *asus = dev_get_drvdata(dev);
> +    return fan_curve_store(asus, buf, count, ASUS_WMI_DEVID_CPU_FAN_CURVE,
> +							&asus->cpu_fan_curve.performance,
> +							asus->cpu_fan_curve.performance_default);
> +}
> +
> +static DEVICE_ATTR_RW(cpu_fan_curve_performance);
> +
> +static ssize_t cpu_fan_curve_quiet_show(struct device *dev,
> +				   struct device_attribute *attr, char *buf)
> +{
> +	struct asus_wmi *asus = dev_get_drvdata(dev);
> +	return scnprintf(buf, PAGE_SIZE, "%s", asus->cpu_fan_curve.quiet);
> +}
> +
> +static ssize_t cpu_fan_curve_quiet_store(struct device *dev,
> +				    struct device_attribute *attr,
> +				    const char *buf, size_t count)
> +{
> +    struct asus_wmi *asus = dev_get_drvdata(dev);
> +    return fan_curve_store(asus, buf, count, ASUS_WMI_DEVID_CPU_FAN_CURVE,
> +							&asus->cpu_fan_curve.quiet,
> +							asus->cpu_fan_curve.quiet_default);
> +}
> +
> +static DEVICE_ATTR_RW(cpu_fan_curve_quiet);
> +
> +/*
> + * GPU Fan Curves
> +*/
> +
> +static ssize_t gpu_fan_curve_balanced_show(struct device *dev,
> +				   struct device_attribute *attr, char *buf)
> +{
> +	struct asus_wmi *asus = dev_get_drvdata(dev);
> +	return scnprintf(buf, PAGE_SIZE, "%s", asus->gpu_fan_curve.balanced);
> +}
> +
> +static ssize_t gpu_fan_curve_balanced_store(struct device *dev,
> +				    struct device_attribute *attr,
> +				    const char *buf, size_t count)
> +{
> +    struct asus_wmi *asus = dev_get_drvdata(dev);
> +    return fan_curve_store(asus, buf, count, ASUS_WMI_DEVID_GPU_FAN_CURVE,
> +							&asus->gpu_fan_curve.balanced,
> +							asus->gpu_fan_curve.balanced_default);
> +}
> +
> +static DEVICE_ATTR_RW(gpu_fan_curve_balanced);
> +
> +static ssize_t gpu_fan_curve_performance_show(struct device *dev,
> +				   struct device_attribute *attr, char *buf)
> +{
> +	struct asus_wmi *asus = dev_get_drvdata(dev);
> +	return scnprintf(buf, PAGE_SIZE, "%s", asus->gpu_fan_curve.performance);
> +}
> +
> +static ssize_t gpu_fan_curve_performance_store(struct device *dev,
> +				    struct device_attribute *attr,
> +				    const char *buf, size_t count)
> +{
> +    struct asus_wmi *asus = dev_get_drvdata(dev);
> +    return fan_curve_store(asus, buf, count, ASUS_WMI_DEVID_GPU_FAN_CURVE,
> +							&asus->gpu_fan_curve.performance,
> +							asus->gpu_fan_curve.performance_default);
> +}
> +
> +static DEVICE_ATTR_RW(gpu_fan_curve_performance);
> +
> +static ssize_t gpu_fan_curve_quiet_show(struct device *dev,
> +				   struct device_attribute *attr, char *buf)
> +{
> +	struct asus_wmi *asus = dev_get_drvdata(dev);
> +	return scnprintf(buf, PAGE_SIZE, "%s", asus->gpu_fan_curve.quiet);
> +}
> +
> +static ssize_t gpu_fan_curve_quiet_store(struct device *dev,
> +				    struct device_attribute *attr,
> +				    const char *buf, size_t count)
> +{
> +    struct asus_wmi *asus = dev_get_drvdata(dev);
> +    return fan_curve_store(asus, buf, count, ASUS_WMI_DEVID_GPU_FAN_CURVE,
> +							&asus->gpu_fan_curve.quiet,
> +							asus->gpu_fan_curve.quiet_default);
> +}
> +
> +static DEVICE_ATTR_RW(gpu_fan_curve_quiet);

Even though it is a hwmon thing, I think `SENSOR_ATTR_2()` (from linux/hwmon-sysfs.h)
would be very useful here as you'd avoid creating n+1 functions, e.g:

  static ssize_t fan_curve_show(struct device *dev, struct device_attribute *attr, char *buf)
  {
    struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
    struct asus_wmi *asus = dev_get_drvdata(dev);

    /*
     * if you stored fan curves in an array, you could then access the fan
     * curve in `asus->fans[sattr->index].curves[sattr->nr]`
     * /
  }

  static SENSOR_DEVICE_ATTR_2(some_name1, 0644, fan_curve_show, fan_curve_store,
                              FAN_CPU /* index in the "fans" array */,
                              ASUS_THROTTLE_THERMAL_POLICY_SILENT /* index in the "curves" array */);


> +
> +/*
> + * Profiles with enabled fan curve setting
> +*/
> +
> +static int enabled_fan_curve_profiles_write(struct asus_wmi *asus,
> +											const char *names)
> +{
> +    char *buf, *set, *set_end;
> +    int err;
> +
> +    buf = set_end = kstrdup(names, GFP_KERNEL);
> +
> +	/* Reset before checking */
> +	asus->enabled_fan_curve_profiles.balanced = false;
> +	asus->enabled_fan_curve_profiles.quiet = false;
> +	asus->enabled_fan_curve_profiles.performance = false;
> +
> +	while( (set = strsep(&set_end, " ")) != NULL ) {
> +		if (set == NULL)

When is this possible?


> +			set = buf;
> +
> +		if (strcmp(set, "balanced") == 0
> +				|| strcmp(set, "balanced\n") == 0)
> +			asus->enabled_fan_curve_profiles.balanced = true;
> +
> +		if (strcmp(set, "quiet") == 0
> +				|| strcmp(set, "quiet\n") == 0)
> +			asus->enabled_fan_curve_profiles.quiet = true;
> +
> +		if (strcmp(set, "performance") == 0
> +				|| strcmp(set, "performance\n") == 0)
> +			asus->enabled_fan_curve_profiles.performance = true;

If you store the enabled curves in an array, and you have a list of profile names,
then `sysfs_match_string()`, will be very helpful here. You could do something like:

  int profile = sysfs_match_string(profile_names, set);
  if (profile < 0) {
    /* not found */
  }

  asus->fan_curve_enabled_for_profile[profile] = true;


> +	}
> +
> +	err = throttle_thermal_policy_write(asus);
> +	if (err)
> +		return err;
> +
> +	kfree(buf);
> +
> +	return 0;
> +}
> +
> +static ssize_t enabled_fan_curve_profiles_show(struct device *dev,
> +				   struct device_attribute *attr, char *buf)
> +{
> +	struct asus_wmi *asus = dev_get_drvdata(dev);
> +	int len = 0;
> +
> +	if (asus->enabled_fan_curve_profiles.balanced)
> +		len += sysfs_emit_at(buf, len, "balanced ");
> +
> +	if (asus->enabled_fan_curve_profiles.performance)
> +		len += sysfs_emit_at(buf, len, "performance ");
> +
> +	if (asus->enabled_fan_curve_profiles.quiet)
> +		len += sysfs_emit_at(buf, len, "quiet ");
> +
> +	len += sysfs_emit_at(buf, len, "\n");
> +	return len;
> +}
> +
> +static ssize_t enabled_fan_curve_profiles_store(struct device *dev,
> +				    struct device_attribute *attr,
> +				    const char *buf, size_t count)
> +{
> +    struct asus_wmi *asus = dev_get_drvdata(dev);
> +	int err;
> +
> +	err = enabled_fan_curve_profiles_write(asus, buf);
> +	if (err)
> +		return err;
> +
> +    return count;
> +}
> +
> +static DEVICE_ATTR_RW(enabled_fan_curve_profiles);
> +
>  /* Throttle thermal policy ****************************************************/
>
>  static int throttle_thermal_policy_check_present(struct asus_wmi *asus)
> @@ -2092,6 +2652,26 @@ static int throttle_thermal_policy_write(struct asus_wmi *asus)
>  		return -EIO;
>  	}
>
> +	if (asus->cpu_fan_curve_available) {
> +		err = fan_curve_cpu_write(asus);
> +		if (err) {
> +			dev_warn(&asus->platform_device->dev,
> +				"Failed to set custom CPU curve for thermal policy: %d\n",
> +				err);
> +			return err;
> +		}
> +	}
> +
> +	if (asus->gpu_fan_curve_available) {
> +		err = fan_curve_gpu_write(asus);
> +		if (err) {
> +			dev_warn(&asus->platform_device->dev,
> +				"Failed to set custom GPU curve for thermal policy: %d\n",
> +				err);
> +			return err;
> +		}
> +	}
> +
>  	return 0;
>  }
>
> @@ -2711,6 +3291,13 @@ static struct attribute *platform_attributes[] = {
>  	&dev_attr_als_enable.attr,
>  	&dev_attr_fan_boost_mode.attr,
>  	&dev_attr_throttle_thermal_policy.attr,
> +	&dev_attr_cpu_fan_curve_balanced.attr,
> +	&dev_attr_cpu_fan_curve_performance.attr,
> +	&dev_attr_cpu_fan_curve_quiet.attr,
> +    &dev_attr_gpu_fan_curve_balanced.attr,
> +	&dev_attr_gpu_fan_curve_performance.attr,
> +	&dev_attr_gpu_fan_curve_quiet.attr,
> +	&dev_attr_enabled_fan_curve_profiles.attr,
>  	&dev_attr_panel_od.attr,
>  	NULL
>  };
> @@ -2741,6 +3328,20 @@ static umode_t asus_sysfs_is_visible(struct kobject *kobj,
>  		ok = asus->fan_boost_mode_available;
>  	else if (attr == &dev_attr_throttle_thermal_policy.attr)
>  		ok = asus->throttle_thermal_policy_available;
> +	else if (attr == &dev_attr_cpu_fan_curve_balanced.attr)
> +		ok = asus->cpu_fan_curve_available;
> +	else if (attr == &dev_attr_cpu_fan_curve_performance.attr)
> +		ok = asus->cpu_fan_curve_available;
> +	else if (attr == &dev_attr_cpu_fan_curve_quiet.attr)
> +		ok = asus->cpu_fan_curve_available;
> +    else if (attr == &dev_attr_gpu_fan_curve_balanced.attr)
> +		ok = asus->gpu_fan_curve_available;
> +	else if (attr == &dev_attr_gpu_fan_curve_performance.attr)
> +		ok = asus->gpu_fan_curve_available;
> +	else if (attr == &dev_attr_gpu_fan_curve_quiet.attr)
> +		ok = asus->gpu_fan_curve_available;
> +	else if (attr == &dev_attr_enabled_fan_curve_profiles.attr)
> +		ok = asus->cpu_fan_curve_available || asus->gpu_fan_curve_available;
>  	else if (attr == &dev_attr_panel_od.attr)
>  		ok = asus->panel_overdrive_available;
>
> @@ -3016,6 +3617,16 @@ static int asus_wmi_add(struct platform_device *pdev)
>  	else
>  		throttle_thermal_policy_set_default(asus);
>
> +	err = custom_fan_check_present(asus, &asus->cpu_fan_curve_available,
> +			ASUS_WMI_DEVID_CPU_FAN_CURVE);
> +	if (err)
> +		goto fail_custom_fan_curve;
> +
> +    err = custom_fan_check_present(asus, &asus->gpu_fan_curve_available,
> +			ASUS_WMI_DEVID_GPU_FAN_CURVE);
> +	if (err)
> +		goto fail_custom_fan_curve;
> +
>  	err = platform_profile_setup(asus);
>  	if (err)
>  		goto fail_platform_profile_setup;
> @@ -3109,6 +3720,7 @@ static int asus_wmi_add(struct platform_device *pdev)
>  	asus_wmi_sysfs_exit(asus->platform_device);
>  fail_sysfs:
>  fail_throttle_thermal_policy:
> +fail_custom_fan_curve:
>  fail_platform_profile_setup:
>  	if (asus->platform_profile_support)
>  		platform_profile_remove();
> diff --git a/include/linux/platform_data/x86/asus-wmi.h b/include/linux/platform_data/x86/asus-wmi.h
> index 17dc5cb6f3f2..a571b47ff362 100644
> --- a/include/linux/platform_data/x86/asus-wmi.h
> +++ b/include/linux/platform_data/x86/asus-wmi.h
> @@ -77,6 +77,8 @@
>  #define ASUS_WMI_DEVID_THERMAL_CTRL	0x00110011
>  #define ASUS_WMI_DEVID_FAN_CTRL		0x00110012 /* deprecated */
>  #define ASUS_WMI_DEVID_CPU_FAN_CTRL	0x00110013
> +#define ASUS_WMI_DEVID_CPU_FAN_CURVE	0x00110024
> +#define ASUS_WMI_DEVID_GPU_FAN_CURVE	0x00110025
>
>  /* Power */
>  #define ASUS_WMI_DEVID_PROCESSOR_STATE	0x00120012
> --
> 2.31.1


Best regards,
Barnabás Pőcze

Re: [PATCH v5] asus-wmi: Add support for custom fan curves

[Guenter Roeck]

On 8/27/21 8:26 AM, Barnabás Pőcze wrote:
> Hi
> 
> 
> +CC Guenter Roeck as he may be able to tell us if there's an established
> way to export fan curves.
> 

If I understand the context correctly, one would normally define pairs
of pwmX_auto_pointN_temp and pwmX_auto_pointN_pwm, with _temp
being the temperature in milli-degrees C and _pwm being a pwm value
between 0 and 255. Normally the X would refer to different fans/pwm
channels, but one could "tweak" that and declare that pwm1 is quiet,
pwm2 is default, and pwm3 is performance. One could then use pwm1_enable
values (2..4) to select the active mode.

The format isn't documented here, though, so it is hard to say if that
would be a good match. And I won't start analyzing the code trying
to understand in detail what it actually does.

Guenter

> I have added a couple comments.
> There are places where spaces are used instead of tabs.
> 
> 
> 2021. augusztus 27., péntek 1:42 keltezéssel, Luke D. Jones írta:
>> Add support for custom fan curves found on some ASUS ROG laptops.
>>
>> These laptops have the ability to set a custom curve for the CPU
>> and GPU fans via an ACPI method call. This patch enables this,
>> additionally enabling custom fan curves per-profile, where profile
>> here means each of the 3 levels of "throttle_thermal_policy".
>>
>> Signed-off-by: Luke D. Jones <luke@ljones.dev>
>> ---
>>   drivers/platform/x86/asus-wmi.c            | 616 ++++++++++++++++++++-
>>   include/linux/platform_data/x86/asus-wmi.h |   2 +
>>   2 files changed, 616 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c
>> index cc5811844012..944644ae0acd 100644
>> --- a/drivers/platform/x86/asus-wmi.c
>> +++ b/drivers/platform/x86/asus-wmi.c
>> @@ -108,6 +108,11 @@ module_param(fnlock_default, bool, 0444);
>>
>>   static const char * const ashs_ids[] = { "ATK4001", "ATK4002", NULL };
>>
>> +static int throttle_thermal_policy_write(struct asus_wmi*);
>> +static ssize_t fan_curve_store(struct asus_wmi *asus, const char *buf,
>> +								size_t count, u32 dev, char **curve,
>> +								char *default_curve);
>> +
>>   static bool ashs_present(void)
>>   {
>>   	int i = 0;
>> @@ -122,7 +127,8 @@ struct bios_args {
>>   	u32 arg0;
>>   	u32 arg1;
>>   	u32 arg2; /* At least TUF Gaming series uses 3 dword input buffer. */
>> -	u32 arg4;
>> +	u32 arg3;
>> +	u32 arg4; /* Some ROG laptops require a full 5 input args */
>>   	u32 arg5;
>>   } __packed;
>>
>> @@ -173,6 +179,21 @@ enum fan_type {
>>   	FAN_TYPE_SPEC83,	/* starting in Spec 8.3, use CPU_FAN_CTRL */
>>   };
>>
>> +struct fan_curve {
>> +	char *balanced;
>> +	char *balanced_default;
>> +	char *performance;
>> +	char *performance_default;
>> +	char *quiet;
>> +	char *quiet_default;
>> +};
>> +
>> +struct enabled_fan_curves {
>> +	bool balanced;
>> +	bool performance;
>> +	bool quiet;
>> +};
>> +
>>   struct asus_wmi {
>>   	int dsts_id;
>>   	int spec;
>> @@ -220,6 +241,14 @@ struct asus_wmi {
>>   	bool throttle_thermal_policy_available;
>>   	u8 throttle_thermal_policy_mode;
>>
>> +	bool cpu_fan_curve_available;
>> +	struct fan_curve cpu_fan_curve;
>> +
>> +    bool gpu_fan_curve_available;
>> +	struct fan_curve gpu_fan_curve;
>> +
>> +	struct enabled_fan_curves enabled_fan_curve_profiles;
> 
> I would suggest something like the following:
> 
>    struct fan_curve {
>      /* bool enabled; */
>      u8 temps[FAN_CURVE_SIZE];
>      u8 percents[FAN_CURVE_SIZE];
>    };
> 
>    struct fan {
>      bool available;
>      struct fan_curve curves[NUM_PERF_PROFILES];
>    };
> 
>    struct asus_wmi {
>      ...
> 
>      struct fan fans[NUM_FANS];
> 
>      bool fan_curve_enabled_for_profile[NUM_PERF_PROFILES];
>      /* or maybe you could add it as `bool enabled;` into the inner struct */
>    };
> 
> see the reason later.
> 
> 
>> +
>>   	struct platform_profile_handler platform_profile_handler;
>>   	bool platform_profile_support;
>>
>> @@ -285,6 +314,85 @@ int asus_wmi_evaluate_method(u32 method_id, u32 arg0, u32 arg1, u32 *retval)
>>   }
>>   EXPORT_SYMBOL_GPL(asus_wmi_evaluate_method);
>>
>> +static int asus_wmi_evaluate_method5(u32 method_id,
>> +		u32 arg0, u32 arg1, u32 arg2, u32 arg3, u32 arg4, u32 *retval)
>> +{
>> +	struct bios_args args = {
>> +		.arg0 = arg0,
>> +		.arg1 = arg1,
>> +		.arg2 = arg2,
>> +		.arg3 = arg3,
>> +		.arg4 = arg4,
>> +	};
>> +	struct acpi_buffer input = { (acpi_size) sizeof(args), &args };
>> +	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
>> +	acpi_status status;
>> +	union acpi_object *obj;
>> +	u32 tmp = 0;
>> +
>> +	status = wmi_evaluate_method(ASUS_WMI_MGMT_GUID, 0, method_id,
>> +				     &input, &output);
>> +
>> +	if (ACPI_FAILURE(status))
>> +		return -EIO;
>> +
>> +	obj = (union acpi_object *)output.pointer;
> 
> Small thing, but this cast is unnecessary.
> 
> 
>> +	if (obj && obj->type == ACPI_TYPE_INTEGER)
>> +		tmp = (u32) obj->integer.value;
> 
> Same here.
> 
> 
>> +
>> +	if (retval)
>> +		*retval = tmp;
>> +
>> +	kfree(obj);
>> +
>> +	if (tmp == ASUS_WMI_UNSUPPORTED_METHOD)
>> +		return -ENODEV;
>> +
>> +	return 0;
>> +}
>> +
>> +/*
>> + * Returns as an error if the method output is not a buffer. Typically this
>> + * means that the method called is unsupported.
>> +*/
>> +static int asus_wmi_evaluate_method_buf(u32 method_id,
>> +		u32 arg0, u32 arg1, u8 *ret_buffer)
>> +{
>> +	struct bios_args args = {
>> +		.arg0 = arg0,
>> +		.arg1 = arg1,
>> +		.arg2 = 0,
>> +	};
>> +	struct acpi_buffer input = { (acpi_size) sizeof(args), &args };
>> +	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
>> +	acpi_status status;
>> +	union acpi_object *obj;
>> +	u32 int_tmp = 0;
>> +
>> +	status = wmi_evaluate_method(ASUS_WMI_MGMT_GUID, 0, method_id,
>> +				     &input, &output);
>> +
>> +	if (ACPI_FAILURE(status))
>> +		return -EIO;
>> +
>> +	obj = (union acpi_object *)output.pointer;
>> +
>> +	if (obj && obj->type == ACPI_TYPE_INTEGER) {
>> +		int_tmp = (u32) obj->integer.value;
>> +		if (int_tmp == ASUS_WMI_UNSUPPORTED_METHOD)
>> +			return -ENODEV;
>> +		return int_tmp;
>> +	}
>> +
>> +	if (obj && obj->type == ACPI_TYPE_BUFFER) {
>> +		memcpy(ret_buffer, obj->buffer.pointer, obj->buffer.length);
>> +	}
>> +
>> +	kfree(obj);
>> +
>> +	return 0;
>> +}
>> +
>>   static int asus_wmi_evaluate_method_agfn(const struct acpi_buffer args)
>>   {
>>   	struct acpi_buffer input;
>> @@ -1813,7 +1921,7 @@ static ssize_t fan1_label_show(struct device *dev,
>>   					  struct device_attribute *attr,
>>   					  char *buf)
>>   {
>> -	return sprintf(buf, "%s\n", ASUS_FAN_DESC);
>> +	return sprintf(buf, "%s", ASUS_FAN_DESC);
> 
> What is the reason for this change?
> 
> 
>>   }
>>
>>   static ssize_t asus_hwmon_temp1(struct device *dev,
>> @@ -2043,6 +2151,458 @@ static ssize_t fan_boost_mode_store(struct device *dev,
>>   // Fan boost mode: 0 - normal, 1 - overboost, 2 - silent
>>   static DEVICE_ATTR_RW(fan_boost_mode);
>>
>> +/* Custom fan curves per-profile **********************************************/
>> +
>> +/*
>> + * Check if the ability to set fan curves on either fan exists, and store the
>> + * defaults for recall later plus to provide users with a starting point.
>> + *
>> + * "dev" is either CPU_FAN_CURVE or GPU_FAN_CURVE.
>> +*/
>> +static int custom_fan_check_present(struct asus_wmi *asus,
>> +									bool *available, u32 dev)
>> +{
>> +	struct fan_curve *curves = &asus->cpu_fan_curve;
>> +	u8 *buf = kzalloc(16 * sizeof(u8), GFP_KERNEL);
> 
> Is dynamic allocation needed here? No early return frees it.
> 
> 
>> +	/* 15 punctuation marks + 16 sets of numbers up to 3 char each */
>> +	int str_len = 15 + 16 * 3;
> 
> It appears to me that the terminating null byte is not accounted for. E.g.:
> 
>    255:255,255:255,255:255,255:255,255:255,255:255,255:255,255:255
> 
> is itself already 63 (= 15 + 16 x 3) characters.
> 
> And if the maximum length is known, and it's reasonably small, why is it not
> part of the struct as a char array? E.g.:
> 
>    struct fan_curve {
>      char balanced[FAN_CURVE_STR_SIZE]; /* #define FAN_CURVE_STR_SIZE 64 */
>      ...
>    };
> 
> I would actually suggest storing the u8 array itself in the fan curve struct,
> and not a string representation of it. I think the data is easier to deal with
> that way, and the price of formatting it for the sysfs attribute is not
> significant.
> 
> 
>> +	int err;
>> +
>> +	*available = false;
>> +
>> +	if (dev == ASUS_WMI_DEVID_GPU_FAN_CURVE)
>> +		curves = &asus->gpu_fan_curve;
>> +
>> +	/* Balanced default */
>> +	err = asus_wmi_evaluate_method_buf(asus->dsts_id, dev, 0, buf);
>> +	if (err) {
>> +		if (err == -ENODEV)
>> +			return 0;
>> +		return err;
>> +	}
>> +
>> +	curves->balanced = kzalloc(str_len * sizeof(char), GFP_KERNEL);
>> +	if (!curves->balanced)
>> +		return -ENOMEM;
>> +
>> +	curves->balanced_default = kzalloc(str_len * sizeof(char), GFP_KERNEL);
>> +	if (!curves->balanced_default)
>> +		return -ENOMEM;
>> +
>> +	sprintf(curves->balanced, "%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d",
>> +		buf[0], buf[8], buf[1], buf[9], buf[2], buf[10], buf[3], buf[11],
>> +		buf[4], buf[12], buf[5], buf[13], buf[6], buf[14], buf[7], buf[15]);
>> +	sprintf(curves->balanced_default, curves->balanced);
>> +
>> +	/* Quiet default */
>> +	err = asus_wmi_evaluate_method_buf(asus->dsts_id, dev, 1, buf);
>> +	if (err) {
>> +		if (err == -ENODEV)
>> +			return 0;
>> +		return err;
>> +	}
>> +
>> +	curves->quiet = kzalloc(str_len * sizeof(char), GFP_KERNEL);
>> +	if (!curves->quiet)
>> +		return -ENOMEM;
>> +
>> +	curves->quiet_default = kzalloc(str_len * sizeof(char), GFP_KERNEL);
>> +	if (!curves->quiet_default)
>> +		return -ENOMEM;
>> +
>> +	sprintf(curves->quiet, "%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d",
>> +		buf[0], buf[8], buf[1], buf[9], buf[2], buf[10], buf[3], buf[11],
>> +		buf[4], buf[12], buf[5], buf[13], buf[6], buf[14], buf[7], buf[15]);
>> +	sprintf(curves->quiet_default, curves->quiet);
>> +
>> +	/* Performance default */
>> +	err = asus_wmi_evaluate_method_buf(asus->dsts_id, dev, 2, buf);
>> +	if (err) {
>> +		if (err == -ENODEV)
>> +			return 0;
>> +		return err;
>> +	}
>> +
>> +	curves->performance = kzalloc(str_len * sizeof(char), GFP_KERNEL);
>> +	if (!curves->performance)
>> +		return -ENOMEM;
>> +
>> +	curves->performance_default = kzalloc(str_len * sizeof(char), GFP_KERNEL);
>> +	if (!curves->performance_default)
>> +		return -ENOMEM;
>> +
>> +	sprintf(curves->performance,
>> +		"%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d",
>> +		buf[0], buf[8], buf[1], buf[9], buf[2], buf[10], buf[3], buf[11],
>> +		buf[4], buf[12], buf[5], buf[13], buf[6], buf[14], buf[7], buf[15]);
>> +	sprintf(curves->performance_default, curves->performance);
> 
> More or less the same code is repeated three times, I'd consider adding an e.g.
> 
>    void fan_curve_to_str(..., char[static FAN_CURVE_STR_SIZE]);
> 
> function.
> 
> 
>> +
>> +	kfree(buf);
>> +
>> +	*available = true;
>> +	return 0;
>> +}
>> +
>> +/*
>> + * The expected input is of the format
>> + *     "30:1,49:2,59:3,69:4,79:31,89:49,99:56,109:58"
>> + * where a pair is 30:1, with 30 = temperature, and 1 = percentage
>> +*/
>> +static int fan_curve_write(struct asus_wmi *asus, u32 dev, char *curve)
>> +{
>> +    char * buf, *set, *pair_tmp, *pair, *set_end, *pair_end;
>> +    int err, ret;
>> +
>> +	char *set_delimiter = ",";
>> +	char *pair_delimiter = ":";
>> +	bool half_complete = false;
>> +	bool pair_start = true;
>> +	u32 prev_percent = 0;
>> +	u32 prev_temp = 0;
>> +	u32 percent = 0;
>> +	u32 shift = 0;
>> +	u32 temp = 0;
>> +    u32 arg1 = 0;
>> +    u32 arg2 = 0;
>> +    u32 arg3 = 0;
>> +    u32 arg4 = 0;
>> +
>> +    buf = set_end = pair_end = kstrdup(curve, GFP_KERNEL);
>> +
>> +	while( (set = strsep(&set_end, set_delimiter)) != NULL ) {
>> +		pair_tmp = kstrdup(set, GFP_KERNEL);
>> +        pair_start = true;
>> +		while( (pair = strsep(&pair_tmp, pair_delimiter)) != NULL ) {
>> +			err = kstrtouint(pair, 10, &ret);
>> +            if (err) {
>> +                kfree(pair_tmp);
>> +                kfree(buf);
>> +                return err;
>> +            }
>> +
>> +            if (pair_start) {
>> +                temp = ret;
>> +                pair_start = false;
>> +            } else {
>> +                percent = ret;
>> +            }
>> +		}
>> +		kfree(pair_tmp);
>> +
>> +		if (temp < prev_temp || percent < prev_percent || percent > 100) {
>> +            pr_info("Fan curve invalid");
>> +			pr_info("A value is sequentially lower or percentage is > 100");
>> +            kfree(buf);
>> +            return -EINVAL;
>> +        }
>> +
>> +        prev_temp = temp;
>> +        prev_percent = percent;
>> +
>> +        if (!half_complete) {
>> +            arg1 += temp << shift;
>> +            arg3 += percent << shift;
>> +        } else {
>> +            arg2 += temp << shift;
>> +            arg4 += percent << shift;
>> +        }
> 
> As far as I see using 64-bit integers would avoid the need for `half_complete`, et al.
> 
> 
>> +        shift += 8;
>> +
>> +        if (shift == 32) {
>> +            shift = 0;
>> +            half_complete = true;
>> +        }
>> +	}
>> +	kfree(buf);
>> +
> 
> If you don't insist on using commas, I think it is much simpler to
> parse it using `sscanf()`, e.g.:
> 
>    unsigned int temp, prct;
>    int at = 0, len;
> 
>    while (sscanf(&buf[at], "%u:%u %n", &temp, &prct, &len) == 2) {
>      /* process `temp` and `prct` */
> 
>      at += len;
>    }
> 
>    if (buf[at] != '\0')
>      /* error */;
> 
> This also has the advantage that you don't need dynamic memory allocation.
> 
> 
>> +    return asus_wmi_evaluate_method5(ASUS_WMI_METHODID_DEVS, dev,
>> +									 arg1, arg2, arg3, arg4, &ret);
>> +}
>> +
>> +static int fan_curve_cpu_write(struct asus_wmi *asus)
>> +{
>> +	char *curve = NULL;
>> +	int err, mode;
>> +
>> +	mode = asus->throttle_thermal_policy_mode;
>> +
>> +	if (mode == ASUS_THROTTLE_THERMAL_POLICY_DEFAULT
>> +					&& asus->enabled_fan_curve_profiles.balanced) {
>> +		curve = asus->cpu_fan_curve.balanced;
>> +	} else if (mode == ASUS_THROTTLE_THERMAL_POLICY_OVERBOOST
>> +					&& asus->enabled_fan_curve_profiles.performance) {
>> +		curve = asus->cpu_fan_curve.performance;
>> +	} else if (mode == ASUS_THROTTLE_THERMAL_POLICY_SILENT
>> +					&& asus->enabled_fan_curve_profiles.quiet) {
>> +		curve = asus->cpu_fan_curve.quiet;
>> +	}
>> +
>> +	if (curve != NULL) {
>> +		err = fan_curve_write(asus, ASUS_WMI_DEVID_CPU_FAN_CURVE, curve);
>> +		if (err)
>> +			return err;
>> +	}
>> +	return 0;
>> +}
>> +
>> +
>> +static int fan_curve_gpu_write(struct asus_wmi *asus)
>> +{
>> +	char *curve = NULL;
>> +	int err, mode;
>> +
>> +	mode = asus->throttle_thermal_policy_mode;
>> +
>> +	if (mode == ASUS_THROTTLE_THERMAL_POLICY_DEFAULT
>> +					&& asus->enabled_fan_curve_profiles.balanced) {
>> +		curve = asus->gpu_fan_curve.balanced;
>> +	} else if (mode == ASUS_THROTTLE_THERMAL_POLICY_OVERBOOST
>> +					&& asus->enabled_fan_curve_profiles.performance) {
>> +		curve = asus->gpu_fan_curve.performance;
>> +	} else if (mode == ASUS_THROTTLE_THERMAL_POLICY_SILENT
>> +					&& asus->enabled_fan_curve_profiles.quiet) {
>> +		curve = asus->gpu_fan_curve.quiet;
>> +	}
>> +
>> +	if (curve != NULL) {
>> +		err = fan_curve_write(asus, ASUS_WMI_DEVID_GPU_FAN_CURVE, curve);
>> +		if (err)
>> +			return err;
>> +	}
>> +	return 0;
>> +}
>> +
>> +static ssize_t fan_curve_store(struct asus_wmi *asus, const char *buf,
>> +								size_t count, u32 dev, char **curve,
>> +								char *default_curve)
>> +{
>> +    int err;
>> +
>> +	/* Allow a user to write "" or " " to erase a curve setting */
>> +	if (strlen(buf) <= 1 || strcmp(buf, " \n") == 0) {
>> +		kfree(*curve);
>> +		*curve = kstrdup(default_curve, GFP_KERNEL);
>> +		err = throttle_thermal_policy_write(asus);
>> +		if (err)
>> +			return err;
>> +		return count;
>> +	}
>> +
>> +	if (*curve)
>> +		kfree(*curve);
>> +    *curve = kstrdup(buf, GFP_KERNEL);
>> +
>> +	/* Maybe activate fan curve if in associated mode */
>> +	err = throttle_thermal_policy_write(asus);
>> +	if (err) {
>> +		kfree(*curve);
>> +		*curve = kstrdup(default_curve, GFP_KERNEL);
>> +		return err;
>> +	}
>> +
>> +    return count;
>> +}
>> +
>> +/*
>> + * CPU Fan Curves
>> +*/
>> +
>> +static ssize_t cpu_fan_curve_balanced_show(struct device *dev,
>> +				   struct device_attribute *attr, char *buf)
>> +{
>> +	struct asus_wmi *asus = dev_get_drvdata(dev);
>> +	return scnprintf(buf, PAGE_SIZE, "%s", asus->cpu_fan_curve.balanced);
>> +}
>> +
>> +static ssize_t cpu_fan_curve_balanced_store(struct device *dev,
>> +				    struct device_attribute *attr,
>> +				    const char *buf, size_t count)
>> +{
>> +    struct asus_wmi *asus = dev_get_drvdata(dev);
>> +    return fan_curve_store(asus, buf, count, ASUS_WMI_DEVID_CPU_FAN_CURVE,
>> +							&asus->cpu_fan_curve.balanced,
>> +							asus->cpu_fan_curve.balanced_default);
>> +}
>> +
>> +static DEVICE_ATTR_RW(cpu_fan_curve_balanced);
>> +
>> +static ssize_t cpu_fan_curve_performance_show(struct device *dev,
>> +				   struct device_attribute *attr, char *buf)
>> +{
>> +	struct asus_wmi *asus = dev_get_drvdata(dev);
>> +	return scnprintf(buf, PAGE_SIZE, "%s", asus->cpu_fan_curve.performance);
>> +}
>> +
>> +static ssize_t cpu_fan_curve_performance_store(struct device *dev,
>> +				    struct device_attribute *attr,
>> +				    const char *buf, size_t count)
>> +{
>> +    struct asus_wmi *asus = dev_get_drvdata(dev);
>> +    return fan_curve_store(asus, buf, count, ASUS_WMI_DEVID_CPU_FAN_CURVE,
>> +							&asus->cpu_fan_curve.performance,
>> +							asus->cpu_fan_curve.performance_default);
>> +}
>> +
>> +static DEVICE_ATTR_RW(cpu_fan_curve_performance);
>> +
>> +static ssize_t cpu_fan_curve_quiet_show(struct device *dev,
>> +				   struct device_attribute *attr, char *buf)
>> +{
>> +	struct asus_wmi *asus = dev_get_drvdata(dev);
>> +	return scnprintf(buf, PAGE_SIZE, "%s", asus->cpu_fan_curve.quiet);
>> +}
>> +
>> +static ssize_t cpu_fan_curve_quiet_store(struct device *dev,
>> +				    struct device_attribute *attr,
>> +				    const char *buf, size_t count)
>> +{
>> +    struct asus_wmi *asus = dev_get_drvdata(dev);
>> +    return fan_curve_store(asus, buf, count, ASUS_WMI_DEVID_CPU_FAN_CURVE,
>> +							&asus->cpu_fan_curve.quiet,
>> +							asus->cpu_fan_curve.quiet_default);
>> +}
>> +
>> +static DEVICE_ATTR_RW(cpu_fan_curve_quiet);
>> +
>> +/*
>> + * GPU Fan Curves
>> +*/
>> +
>> +static ssize_t gpu_fan_curve_balanced_show(struct device *dev,
>> +				   struct device_attribute *attr, char *buf)
>> +{
>> +	struct asus_wmi *asus = dev_get_drvdata(dev);
>> +	return scnprintf(buf, PAGE_SIZE, "%s", asus->gpu_fan_curve.balanced);
>> +}
>> +
>> +static ssize_t gpu_fan_curve_balanced_store(struct device *dev,
>> +				    struct device_attribute *attr,
>> +				    const char *buf, size_t count)
>> +{
>> +    struct asus_wmi *asus = dev_get_drvdata(dev);
>> +    return fan_curve_store(asus, buf, count, ASUS_WMI_DEVID_GPU_FAN_CURVE,
>> +							&asus->gpu_fan_curve.balanced,
>> +							asus->gpu_fan_curve.balanced_default);
>> +}
>> +
>> +static DEVICE_ATTR_RW(gpu_fan_curve_balanced);
>> +
>> +static ssize_t gpu_fan_curve_performance_show(struct device *dev,
>> +				   struct device_attribute *attr, char *buf)
>> +{
>> +	struct asus_wmi *asus = dev_get_drvdata(dev);
>> +	return scnprintf(buf, PAGE_SIZE, "%s", asus->gpu_fan_curve.performance);
>> +}
>> +
>> +static ssize_t gpu_fan_curve_performance_store(struct device *dev,
>> +				    struct device_attribute *attr,
>> +				    const char *buf, size_t count)
>> +{
>> +    struct asus_wmi *asus = dev_get_drvdata(dev);
>> +    return fan_curve_store(asus, buf, count, ASUS_WMI_DEVID_GPU_FAN_CURVE,
>> +							&asus->gpu_fan_curve.performance,
>> +							asus->gpu_fan_curve.performance_default);
>> +}
>> +
>> +static DEVICE_ATTR_RW(gpu_fan_curve_performance);
>> +
>> +static ssize_t gpu_fan_curve_quiet_show(struct device *dev,
>> +				   struct device_attribute *attr, char *buf)
>> +{
>> +	struct asus_wmi *asus = dev_get_drvdata(dev);
>> +	return scnprintf(buf, PAGE_SIZE, "%s", asus->gpu_fan_curve.quiet);
>> +}
>> +
>> +static ssize_t gpu_fan_curve_quiet_store(struct device *dev,
>> +				    struct device_attribute *attr,
>> +				    const char *buf, size_t count)
>> +{
>> +    struct asus_wmi *asus = dev_get_drvdata(dev);
>> +    return fan_curve_store(asus, buf, count, ASUS_WMI_DEVID_GPU_FAN_CURVE,
>> +							&asus->gpu_fan_curve.quiet,
>> +							asus->gpu_fan_curve.quiet_default);
>> +}
>> +
>> +static DEVICE_ATTR_RW(gpu_fan_curve_quiet);
> 
> Even though it is a hwmon thing, I think `SENSOR_ATTR_2()` (from linux/hwmon-sysfs.h)
> would be very useful here as you'd avoid creating n+1 functions, e.g:
> 
>    static ssize_t fan_curve_show(struct device *dev, struct device_attribute *attr, char *buf)
>    {
>      struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
>      struct asus_wmi *asus = dev_get_drvdata(dev);
> 
>      /*
>       * if you stored fan curves in an array, you could then access the fan
>       * curve in `asus->fans[sattr->index].curves[sattr->nr]`
>       * /
>    }
> 
>    static SENSOR_DEVICE_ATTR_2(some_name1, 0644, fan_curve_show, fan_curve_store,
>                                FAN_CPU /* index in the "fans" array */,
>                                ASUS_THROTTLE_THERMAL_POLICY_SILENT /* index in the "curves" array */);
> 
> 
>> +
>> +/*
>> + * Profiles with enabled fan curve setting
>> +*/
>> +
>> +static int enabled_fan_curve_profiles_write(struct asus_wmi *asus,
>> +											const char *names)
>> +{
>> +    char *buf, *set, *set_end;
>> +    int err;
>> +
>> +    buf = set_end = kstrdup(names, GFP_KERNEL);
>> +
>> +	/* Reset before checking */
>> +	asus->enabled_fan_curve_profiles.balanced = false;
>> +	asus->enabled_fan_curve_profiles.quiet = false;
>> +	asus->enabled_fan_curve_profiles.performance = false;
>> +
>> +	while( (set = strsep(&set_end, " ")) != NULL ) {
>> +		if (set == NULL)
> 
> When is this possible?
> 
> 
>> +			set = buf;
>> +
>> +		if (strcmp(set, "balanced") == 0
>> +				|| strcmp(set, "balanced\n") == 0)
>> +			asus->enabled_fan_curve_profiles.balanced = true;
>> +
>> +		if (strcmp(set, "quiet") == 0
>> +				|| strcmp(set, "quiet\n") == 0)
>> +			asus->enabled_fan_curve_profiles.quiet = true;
>> +
>> +		if (strcmp(set, "performance") == 0
>> +				|| strcmp(set, "performance\n") == 0)
>> +			asus->enabled_fan_curve_profiles.performance = true;
> 
> If you store the enabled curves in an array, and you have a list of profile names,
> then `sysfs_match_string()`, will be very helpful here. You could do something like:
> 
>    int profile = sysfs_match_string(profile_names, set);
>    if (profile < 0) {
>      /* not found */
>    }
> 
>    asus->fan_curve_enabled_for_profile[profile] = true;
> 
> 
>> +	}
>> +
>> +	err = throttle_thermal_policy_write(asus);
>> +	if (err)
>> +		return err;
>> +
>> +	kfree(buf);
>> +
>> +	return 0;
>> +}
>> +
>> +static ssize_t enabled_fan_curve_profiles_show(struct device *dev,
>> +				   struct device_attribute *attr, char *buf)
>> +{
>> +	struct asus_wmi *asus = dev_get_drvdata(dev);
>> +	int len = 0;
>> +
>> +	if (asus->enabled_fan_curve_profiles.balanced)
>> +		len += sysfs_emit_at(buf, len, "balanced ");
>> +
>> +	if (asus->enabled_fan_curve_profiles.performance)
>> +		len += sysfs_emit_at(buf, len, "performance ");
>> +
>> +	if (asus->enabled_fan_curve_profiles.quiet)
>> +		len += sysfs_emit_at(buf, len, "quiet ");
>> +
>> +	len += sysfs_emit_at(buf, len, "\n");
>> +	return len;
>> +}
>> +
>> +static ssize_t enabled_fan_curve_profiles_store(struct device *dev,
>> +				    struct device_attribute *attr,
>> +				    const char *buf, size_t count)
>> +{
>> +    struct asus_wmi *asus = dev_get_drvdata(dev);
>> +	int err;
>> +
>> +	err = enabled_fan_curve_profiles_write(asus, buf);
>> +	if (err)
>> +		return err;
>> +
>> +    return count;
>> +}
>> +
>> +static DEVICE_ATTR_RW(enabled_fan_curve_profiles);
>> +
>>   /* Throttle thermal policy ****************************************************/
>>
>>   static int throttle_thermal_policy_check_present(struct asus_wmi *asus)
>> @@ -2092,6 +2652,26 @@ static int throttle_thermal_policy_write(struct asus_wmi *asus)
>>   		return -EIO;
>>   	}
>>
>> +	if (asus->cpu_fan_curve_available) {
>> +		err = fan_curve_cpu_write(asus);
>> +		if (err) {
>> +			dev_warn(&asus->platform_device->dev,
>> +				"Failed to set custom CPU curve for thermal policy: %d\n",
>> +				err);
>> +			return err;
>> +		}
>> +	}
>> +
>> +	if (asus->gpu_fan_curve_available) {
>> +		err = fan_curve_gpu_write(asus);
>> +		if (err) {
>> +			dev_warn(&asus->platform_device->dev,
>> +				"Failed to set custom GPU curve for thermal policy: %d\n",
>> +				err);
>> +			return err;
>> +		} >> +	}
>> +
>>   	return 0;
>>   }
>>
>> @@ -2711,6 +3291,13 @@ static struct attribute *platform_attributes[] = {
>>   	&dev_attr_als_enable.attr,
>>   	&dev_attr_fan_boost_mode.attr,
>>   	&dev_attr_throttle_thermal_policy.attr,
>> +	&dev_attr_cpu_fan_curve_balanced.attr,
>> +	&dev_attr_cpu_fan_curve_performance.attr,
>> +	&dev_attr_cpu_fan_curve_quiet.attr,
>> +    &dev_attr_gpu_fan_curve_balanced.attr,
>> +	&dev_attr_gpu_fan_curve_performance.attr,
>> +	&dev_attr_gpu_fan_curve_quiet.attr,
>> +	&dev_attr_enabled_fan_curve_profiles.attr,
>>   	&dev_attr_panel_od.attr,
>>   	NULL
>>   };
>> @@ -2741,6 +3328,20 @@ static umode_t asus_sysfs_is_visible(struct kobject *kobj,
>>   		ok = asus->fan_boost_mode_available;
>>   	else if (attr == &dev_attr_throttle_thermal_policy.attr)
>>   		ok = asus->throttle_thermal_policy_available;
>> +	else if (attr == &dev_attr_cpu_fan_curve_balanced.attr)
>> +		ok = asus->cpu_fan_curve_available;
>> +	else if (attr == &dev_attr_cpu_fan_curve_performance.attr)
>> +		ok = asus->cpu_fan_curve_available;
>> +	else if (attr == &dev_attr_cpu_fan_curve_quiet.attr)
>> +		ok = asus->cpu_fan_curve_available;
>> +    else if (attr == &dev_attr_gpu_fan_curve_balanced.attr)
>> +		ok = asus->gpu_fan_curve_available;
>> +	else if (attr == &dev_attr_gpu_fan_curve_performance.attr)
>> +		ok = asus->gpu_fan_curve_available;
>> +	else if (attr == &dev_attr_gpu_fan_curve_quiet.attr)
>> +		ok = asus->gpu_fan_curve_available;
>> +	else if (attr == &dev_attr_enabled_fan_curve_profiles.attr)
>> +		ok = asus->cpu_fan_curve_available || asus->gpu_fan_curve_available;
>>   	else if (attr == &dev_attr_panel_od.attr)
>>   		ok = asus->panel_overdrive_available;
>>
>> @@ -3016,6 +3617,16 @@ static int asus_wmi_add(struct platform_device *pdev)
>>   	else
>>   		throttle_thermal_policy_set_default(asus);
>>
>> +	err = custom_fan_check_present(asus, &asus->cpu_fan_curve_available,
>> +			ASUS_WMI_DEVID_CPU_FAN_CURVE);
>> +	if (err)
>> +		goto fail_custom_fan_curve;
>> +
>> +    err = custom_fan_check_present(asus, &asus->gpu_fan_curve_available,
>> +			ASUS_WMI_DEVID_GPU_FAN_CURVE);
>> +	if (err)
>> +		goto fail_custom_fan_curve;
>> +
>>   	err = platform_profile_setup(asus);
>>   	if (err)
>>   		goto fail_platform_profile_setup;
>> @@ -3109,6 +3720,7 @@ static int asus_wmi_add(struct platform_device *pdev)
>>   	asus_wmi_sysfs_exit(asus->platform_device);
>>   fail_sysfs:
>>   fail_throttle_thermal_policy:
>> +fail_custom_fan_curve:
>>   fail_platform_profile_setup:
>>   	if (asus->platform_profile_support)
>>   		platform_profile_remove();
>> diff --git a/include/linux/platform_data/x86/asus-wmi.h b/include/linux/platform_data/x86/asus-wmi.h
>> index 17dc5cb6f3f2..a571b47ff362 100644
>> --- a/include/linux/platform_data/x86/asus-wmi.h
>> +++ b/include/linux/platform_data/x86/asus-wmi.h
>> @@ -77,6 +77,8 @@
>>   #define ASUS_WMI_DEVID_THERMAL_CTRL	0x00110011
>>   #define ASUS_WMI_DEVID_FAN_CTRL		0x00110012 /* deprecated */
>>   #define ASUS_WMI_DEVID_CPU_FAN_CTRL	0x00110013
>> +#define ASUS_WMI_DEVID_CPU_FAN_CURVE	0x00110024
>> +#define ASUS_WMI_DEVID_GPU_FAN_CURVE	0x00110025
>>
>>   /* Power */
>>   #define ASUS_WMI_DEVID_PROCESSOR_STATE	0x00120012
>> --
>> 2.31.1
> 
> 
> Best regards,
> Barnabás Pőcze
> 

Re: [PATCH v5] asus-wmi: Add support for custom fan curves

[Luke Jones]

Hi Barnabás,

Many thanks for the quality feedback. I'll try to address some of the 
comments you have and then begin work on changes to suit. I feel it is 
necessary to be clear that C is not a language I'm comfortable in (I 
use Rust 90% of the time) and so I rely on feedback such as what you've 
provided to ensure I'm on the right track.

Okay, so I refactored according to your feedback and the result is a 
pretty different V6 (will submit soon).

On Fri, Aug 27 2021 at 15:26:11 +0000, Barnabás Pőcze 
<pobrn@protonmail.com> wrote:
> Hi
> 
> 
> +CC Guenter Roeck as he may be able to tell us if there's an 
> established
> way to export fan curves.
> 
> I have added a couple comments.
> There are places where spaces are used instead of tabs.
> 
> 
> 2021. augusztus 27., péntek 1:42 keltezéssel, Luke D. Jones írta:
>>  Add support for custom fan curves found on some ASUS ROG laptops.
>> 
>>  These laptops have the ability to set a custom curve for the CPU
>>  and GPU fans via an ACPI method call. This patch enables this,
>>  additionally enabling custom fan curves per-profile, where profile
>>  here means each of the 3 levels of "throttle_thermal_policy".
>> 
>>  Signed-off-by: Luke D. Jones <luke@ljones.dev>
>>  ---
>>   drivers/platform/x86/asus-wmi.c            | 616 
>> ++++++++++++++++++++-
>>   include/linux/platform_data/x86/asus-wmi.h |   2 +
>>   2 files changed, 616 insertions(+), 2 deletions(-)
>> 
>>  diff --git a/drivers/platform/x86/asus-wmi.c 
>> b/drivers/platform/x86/asus-wmi.c
>>  index cc5811844012..944644ae0acd 100644
>>  --- a/drivers/platform/x86/asus-wmi.c
>>  +++ b/drivers/platform/x86/asus-wmi.c
>>  @@ -108,6 +108,11 @@ module_param(fnlock_default, bool, 0444);
>> 
>>   static const char * const ashs_ids[] = { "ATK4001", "ATK4002", 
>> NULL };
>> 
>>  +static int throttle_thermal_policy_write(struct asus_wmi*);
>>  +static ssize_t fan_curve_store(struct asus_wmi *asus, const char 
>> *buf,
>>  +								size_t count, u32 dev, char **curve,
>>  +								char *default_curve);
>>  +
>>   static bool ashs_present(void)
>>   {
>>   	int i = 0;
>>  @@ -122,7 +127,8 @@ struct bios_args {
>>   	u32 arg0;
>>   	u32 arg1;
>>   	u32 arg2; /* At least TUF Gaming series uses 3 dword input 
>> buffer. */
>>  -	u32 arg4;
>>  +	u32 arg3;
>>  +	u32 arg4; /* Some ROG laptops require a full 5 input args */
>>   	u32 arg5;
>>   } __packed;
>> 
>>  @@ -173,6 +179,21 @@ enum fan_type {
>>   	FAN_TYPE_SPEC83,	/* starting in Spec 8.3, use CPU_FAN_CTRL */
>>   };
>> 
>>  +struct fan_curve {
>>  +	char *balanced;
>>  +	char *balanced_default;
>>  +	char *performance;
>>  +	char *performance_default;
>>  +	char *quiet;
>>  +	char *quiet_default;
>>  +};
>>  +
>>  +struct enabled_fan_curves {
>>  +	bool balanced;
>>  +	bool performance;
>>  +	bool quiet;
>>  +};
>>  +
>>   struct asus_wmi {
>>   	int dsts_id;
>>   	int spec;
>>  @@ -220,6 +241,14 @@ struct asus_wmi {
>>   	bool throttle_thermal_policy_available;
>>   	u8 throttle_thermal_policy_mode;
>> 
>>  +	bool cpu_fan_curve_available;
>>  +	struct fan_curve cpu_fan_curve;
>>  +
>>  +    bool gpu_fan_curve_available;
>>  +	struct fan_curve gpu_fan_curve;
>>  +
>>  +	struct enabled_fan_curves enabled_fan_curve_profiles;
> 
> I would suggest something like the following:
> 
>   struct fan_curve {
>     /* bool enabled; */
>     u8 temps[FAN_CURVE_SIZE];
>     u8 percents[FAN_CURVE_SIZE];
>   };
> 
>   struct fan {
>     bool available;
>     struct fan_curve curves[NUM_PERF_PROFILES];
>   };
> 
>   struct asus_wmi {
>     ...
> 
>     struct fan fans[NUM_FANS];
> 
>     bool fan_curve_enabled_for_profile[NUM_PERF_PROFILES];
>     /* or maybe you could add it as `bool enabled;` into the inner 
> struct */
>   };
> 
> see the reason later.

I initially started doing something like this but took current path for 
a reason I don't remember. Might have been personal preference to be 
more explicit. However I will use what you've suggested here, paired 
with an enum for the 3 profiles so they are named. There are only 3 
possible profiles due to curves paired with throttle_thermal_policy in 
the related platform_profile patch.

> 
> 
>>  +
>>   	struct platform_profile_handler platform_profile_handler;
>>   	bool platform_profile_support;
>> 
>>  @@ -285,6 +314,85 @@ int asus_wmi_evaluate_method(u32 method_id, 
>> u32 arg0, u32 arg1, u32 *retval)
>>   }
>>   EXPORT_SYMBOL_GPL(asus_wmi_evaluate_method);
>> 
>>  +static int asus_wmi_evaluate_method5(u32 method_id,
>>  +		u32 arg0, u32 arg1, u32 arg2, u32 arg3, u32 arg4, u32 *retval)
>>  +{
>>  +	struct bios_args args = {
>>  +		.arg0 = arg0,
>>  +		.arg1 = arg1,
>>  +		.arg2 = arg2,
>>  +		.arg3 = arg3,
>>  +		.arg4 = arg4,
>>  +	};
>>  +	struct acpi_buffer input = { (acpi_size) sizeof(args), &args };
>>  +	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
>>  +	acpi_status status;
>>  +	union acpi_object *obj;
>>  +	u32 tmp = 0;
>>  +
>>  +	status = wmi_evaluate_method(ASUS_WMI_MGMT_GUID, 0, method_id,
>>  +				     &input, &output);
>>  +
>>  +	if (ACPI_FAILURE(status))
>>  +		return -EIO;
>>  +
>>  +	obj = (union acpi_object *)output.pointer;
> 
> Small thing, but this cast is unnecessary.

Copy/paste from asus_wmi_evaluate_method3(). There are 3 other examples 
of that. Being unfamiliar with many things I tend to read the source to 
find examples of what I want to achieve. In either case, I'll update 
this.

> 
> 
>>  +	if (obj && obj->type == ACPI_TYPE_INTEGER)
>>  +		tmp = (u32) obj->integer.value;
> 
> Same here.

Also from asus_wmi_evaluate_method3()

> 
> 
>>  +
>>  +	if (retval)
>>  +		*retval = tmp;
>>  +
>>  +	kfree(obj);
>>  +
>>  +	if (tmp == ASUS_WMI_UNSUPPORTED_METHOD)
>>  +		return -ENODEV;
>>  +
>>  +	return 0;
>>  +}
>>  +
>>  +/*
>>  + * Returns as an error if the method output is not a buffer. 
>> Typically this
>>  + * means that the method called is unsupported.
>>  +*/
>>  +static int asus_wmi_evaluate_method_buf(u32 method_id,
>>  +		u32 arg0, u32 arg1, u8 *ret_buffer)
>>  +{
>>  +	struct bios_args args = {
>>  +		.arg0 = arg0,
>>  +		.arg1 = arg1,
>>  +		.arg2 = 0,
>>  +	};
>>  +	struct acpi_buffer input = { (acpi_size) sizeof(args), &args };
>>  +	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
>>  +	acpi_status status;
>>  +	union acpi_object *obj;
>>  +	u32 int_tmp = 0;
>>  +
>>  +	status = wmi_evaluate_method(ASUS_WMI_MGMT_GUID, 0, method_id,
>>  +				     &input, &output);
>>  +
>>  +	if (ACPI_FAILURE(status))
>>  +		return -EIO;
>>  +
>>  +	obj = (union acpi_object *)output.pointer;
>>  +
>>  +	if (obj && obj->type == ACPI_TYPE_INTEGER) {
>>  +		int_tmp = (u32) obj->integer.value;
>>  +		if (int_tmp == ASUS_WMI_UNSUPPORTED_METHOD)
>>  +			return -ENODEV;
>>  +		return int_tmp;
>>  +	}
>>  +
>>  +	if (obj && obj->type == ACPI_TYPE_BUFFER) {
>>  +		memcpy(ret_buffer, obj->buffer.pointer, obj->buffer.length);
>>  +	}
>>  +
>>  +	kfree(obj);
>>  +
>>  +	return 0;
>>  +}
>>  +
>>   static int asus_wmi_evaluate_method_agfn(const struct acpi_buffer 
>> args)
>>   {
>>   	struct acpi_buffer input;
>>  @@ -1813,7 +1921,7 @@ static ssize_t fan1_label_show(struct device 
>> *dev,
>>   					  struct device_attribute *attr,
>>   					  char *buf)
>>   {
>>  -	return sprintf(buf, "%s\n", ASUS_FAN_DESC);
>>  +	return sprintf(buf, "%s", ASUS_FAN_DESC);
> 
> What is the reason for this change?

Oops... No reason at all. Not quite sure how that happened, will revert.

> 
> 
>>   }
>> 
>>   static ssize_t asus_hwmon_temp1(struct device *dev,
>>  @@ -2043,6 +2151,458 @@ static ssize_t fan_boost_mode_store(struct 
>> device *dev,
>>   // Fan boost mode: 0 - normal, 1 - overboost, 2 - silent
>>   static DEVICE_ATTR_RW(fan_boost_mode);
>> 
>>  +/* Custom fan curves per-profile 
>> **********************************************/
>>  +
>>  +/*
>>  + * Check if the ability to set fan curves on either fan exists, 
>> and store the
>>  + * defaults for recall later plus to provide users with a starting 
>> point.
>>  + *
>>  + * "dev" is either CPU_FAN_CURVE or GPU_FAN_CURVE.
>>  +*/
>>  +static int custom_fan_check_present(struct asus_wmi *asus,
>>  +									bool *available, u32 dev)
>>  +{
>>  +	struct fan_curve *curves = &asus->cpu_fan_curve;
>>  +	u8 *buf = kzalloc(16 * sizeof(u8), GFP_KERNEL);
> 
> Is dynamic allocation needed here? No early return frees it.

Oh. Just me forgetting how to declare an array and doing something 
silly. Fixed with u8 buf[16];

> 
> 
>>  +	/* 15 punctuation marks + 16 sets of numbers up to 3 char each */
>>  +	int str_len = 15 + 16 * 3;
> 
> It appears to me that the terminating null byte is not accounted for. 
> E.g.:
> 
>   255:255,255:255,255:255,255:255,255:255,255:255,255:255,255:255
> 
> is itself already 63 (= 15 + 16 x 3) characters.
> 
> And if the maximum length is known, and it's reasonably small, why is 
> it not
> part of the struct as a char array? E.g.:
> 
>   struct fan_curve {
>     char balanced[FAN_CURVE_STR_SIZE]; /* #define FAN_CURVE_STR_SIZE 
> 64 */
>     ...
>   };
> 
> I would actually suggest storing the u8 array itself in the fan curve 
> struct,
> and not a string representation of it. I think the data is easier to 
> deal with
> that way, and the price of formatting it for the sysfs attribute is 
> not
> significant.

Yeah I've gone and done it so that the u8 array is stored now. 
Certainly easier to manage.

> 
> 
>>  +	int err;
>>  +
>>  +	*available = false;
>>  +
>>  +	if (dev == ASUS_WMI_DEVID_GPU_FAN_CURVE)
>>  +		curves = &asus->gpu_fan_curve;
>>  +
>>  +	/* Balanced default */
>>  +	err = asus_wmi_evaluate_method_buf(asus->dsts_id, dev, 0, buf);
>>  +	if (err) {
>>  +		if (err == -ENODEV)
>>  +			return 0;
>>  +		return err;
>>  +	}
>>  +
>>  +	curves->balanced = kzalloc(str_len * sizeof(char), GFP_KERNEL);
>>  +	if (!curves->balanced)
>>  +		return -ENOMEM;
>>  +
>>  +	curves->balanced_default = kzalloc(str_len * sizeof(char), 
>> GFP_KERNEL);
>>  +	if (!curves->balanced_default)
>>  +		return -ENOMEM;
>>  +
>>  +	sprintf(curves->balanced, 
>> "%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d",
>>  +		buf[0], buf[8], buf[1], buf[9], buf[2], buf[10], buf[3], buf[11],
>>  +		buf[4], buf[12], buf[5], buf[13], buf[6], buf[14], buf[7], 
>> buf[15]);
>>  +	sprintf(curves->balanced_default, curves->balanced);
>>  +
>>  +	/* Quiet default */
>>  +	err = asus_wmi_evaluate_method_buf(asus->dsts_id, dev, 1, buf);
>>  +	if (err) {
>>  +		if (err == -ENODEV)
>>  +			return 0;
>>  +		return err;
>>  +	}
>>  +
>>  +	curves->quiet = kzalloc(str_len * sizeof(char), GFP_KERNEL);
>>  +	if (!curves->quiet)
>>  +		return -ENOMEM;
>>  +
>>  +	curves->quiet_default = kzalloc(str_len * sizeof(char), 
>> GFP_KERNEL);
>>  +	if (!curves->quiet_default)
>>  +		return -ENOMEM;
>>  +
>>  +	sprintf(curves->quiet, 
>> "%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d",
>>  +		buf[0], buf[8], buf[1], buf[9], buf[2], buf[10], buf[3], buf[11],
>>  +		buf[4], buf[12], buf[5], buf[13], buf[6], buf[14], buf[7], 
>> buf[15]);
>>  +	sprintf(curves->quiet_default, curves->quiet);
>>  +
>>  +	/* Performance default */
>>  +	err = asus_wmi_evaluate_method_buf(asus->dsts_id, dev, 2, buf);
>>  +	if (err) {
>>  +		if (err == -ENODEV)
>>  +			return 0;
>>  +		return err;
>>  +	}
>>  +
>>  +	curves->performance = kzalloc(str_len * sizeof(char), GFP_KERNEL);
>>  +	if (!curves->performance)
>>  +		return -ENOMEM;
>>  +
>>  +	curves->performance_default = kzalloc(str_len * sizeof(char), 
>> GFP_KERNEL);
>>  +	if (!curves->performance_default)
>>  +		return -ENOMEM;
>>  +
>>  +	sprintf(curves->performance,
>>  +		"%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d,%d:%d",
>>  +		buf[0], buf[8], buf[1], buf[9], buf[2], buf[10], buf[3], buf[11],
>>  +		buf[4], buf[12], buf[5], buf[13], buf[6], buf[14], buf[7], 
>> buf[15]);
>>  +	sprintf(curves->performance_default, curves->performance);
> 
> More or less the same code is repeated three times, I'd consider 
> adding an e.g.
> 
>   void fan_curve_to_str(..., char[static FAN_CURVE_STR_SIZE]);
> 
> function.

I guess this part is moot now that the data is stored as u8 array now.

> 
> 
>>  +
>>  +	kfree(buf);
>>  +
>>  +	*available = true;
>>  +	return 0;
>>  +}
>>  +
>>  +/*
>>  + * The expected input is of the format
>>  + *     "30:1,49:2,59:3,69:4,79:31,89:49,99:56,109:58"
>>  + * where a pair is 30:1, with 30 = temperature, and 1 = percentage
>>  +*/
>>  +static int fan_curve_write(struct asus_wmi *asus, u32 dev, char 
>> *curve)
>>  +{
>>  +    char * buf, *set, *pair_tmp, *pair, *set_end, *pair_end;
>>  +    int err, ret;
>>  +
>>  +	char *set_delimiter = ",";
>>  +	char *pair_delimiter = ":";
>>  +	bool half_complete = false;
>>  +	bool pair_start = true;
>>  +	u32 prev_percent = 0;
>>  +	u32 prev_temp = 0;
>>  +	u32 percent = 0;
>>  +	u32 shift = 0;
>>  +	u32 temp = 0;
>>  +    u32 arg1 = 0;
>>  +    u32 arg2 = 0;
>>  +    u32 arg3 = 0;
>>  +    u32 arg4 = 0;
>>  +
>>  +    buf = set_end = pair_end = kstrdup(curve, GFP_KERNEL);
>>  +
>>  +	while( (set = strsep(&set_end, set_delimiter)) != NULL ) {
>>  +		pair_tmp = kstrdup(set, GFP_KERNEL);
>>  +        pair_start = true;
>>  +		while( (pair = strsep(&pair_tmp, pair_delimiter)) != NULL ) {
>>  +			err = kstrtouint(pair, 10, &ret);
>>  +            if (err) {
>>  +                kfree(pair_tmp);
>>  +                kfree(buf);
>>  +                return err;
>>  +            }
>>  +
>>  +            if (pair_start) {
>>  +                temp = ret;
>>  +                pair_start = false;
>>  +            } else {
>>  +                percent = ret;
>>  +            }
>>  +		}
>>  +		kfree(pair_tmp);
>>  +
>>  +		if (temp < prev_temp || percent < prev_percent || percent > 100) 
>> {
>>  +            pr_info("Fan curve invalid");
>>  +			pr_info("A value is sequentially lower or percentage is > 100");
>>  +            kfree(buf);
>>  +            return -EINVAL;
>>  +        }
>>  +
>>  +        prev_temp = temp;
>>  +        prev_percent = percent;
>>  +
>>  +        if (!half_complete) {
>>  +            arg1 += temp << shift;
>>  +            arg3 += percent << shift;
>>  +        } else {
>>  +            arg2 += temp << shift;
>>  +            arg4 += percent << shift;
>>  +        }
> 
> As far as I see using 64-bit integers would avoid the need for 
> `half_complete`, et al.

Reworked all that as part of the u8-array stuff. Look forward to seeing 
what you think.

> 
> 
>>  +        shift += 8;
>>  +
>>  +        if (shift == 32) {
>>  +            shift = 0;
>>  +            half_complete = true;
>>  +        }
>>  +	}
>>  +	kfree(buf);
>>  +
> 
> If you don't insist on using commas, I think it is much simpler to
> parse it using `sscanf()`, e.g.:
> 
>   unsigned int temp, prct;
>   int at = 0, len;
> 
>   while (sscanf(&buf[at], "%u:%u %n", &temp, &prct, &len) == 2) {
>     /* process `temp` and `prct` */
> 
>     at += len;
>   }
> 
>   if (buf[at] != '\0')
>     /* error */;
> 
> This also has the advantage that you don't need dynamic memory 
> allocation.

Half the reason I did it in the format of 10:20,30:40,.. is to keep 
close to a format that many people using some external tools for fan 
curves (using acpi_call modue!) are using. I'm open to improvements ofc.

> 
> 
>>  +    return asus_wmi_evaluate_method5(ASUS_WMI_METHODID_DEVS, dev,
>>  +									 arg1, arg2, arg3, arg4, &ret);
>>  +}
>>  +
>>  +static int fan_curve_cpu_write(struct asus_wmi *asus)
>>  +{
>>  +	char *curve = NULL;
>>  +	int err, mode;
>>  +
>>  +	mode = asus->throttle_thermal_policy_mode;
>>  +
>>  +	if (mode == ASUS_THROTTLE_THERMAL_POLICY_DEFAULT
>>  +					&& asus->enabled_fan_curve_profiles.balanced) {
>>  +		curve = asus->cpu_fan_curve.balanced;
>>  +	} else if (mode == ASUS_THROTTLE_THERMAL_POLICY_OVERBOOST
>>  +					&& asus->enabled_fan_curve_profiles.performance) {
>>  +		curve = asus->cpu_fan_curve.performance;
>>  +	} else if (mode == ASUS_THROTTLE_THERMAL_POLICY_SILENT
>>  +					&& asus->enabled_fan_curve_profiles.quiet) {
>>  +		curve = asus->cpu_fan_curve.quiet;
>>  +	}
>>  +
>>  +	if (curve != NULL) {
>>  +		err = fan_curve_write(asus, ASUS_WMI_DEVID_CPU_FAN_CURVE, curve);
>>  +		if (err)
>>  +			return err;
>>  +	}
>>  +	return 0;
>>  +}
>>  +
>>  +
>>  +static int fan_curve_gpu_write(struct asus_wmi *asus)
>>  +{
>>  +	char *curve = NULL;
>>  +	int err, mode;
>>  +
>>  +	mode = asus->throttle_thermal_policy_mode;
>>  +
>>  +	if (mode == ASUS_THROTTLE_THERMAL_POLICY_DEFAULT
>>  +					&& asus->enabled_fan_curve_profiles.balanced) {
>>  +		curve = asus->gpu_fan_curve.balanced;
>>  +	} else if (mode == ASUS_THROTTLE_THERMAL_POLICY_OVERBOOST
>>  +					&& asus->enabled_fan_curve_profiles.performance) {
>>  +		curve = asus->gpu_fan_curve.performance;
>>  +	} else if (mode == ASUS_THROTTLE_THERMAL_POLICY_SILENT
>>  +					&& asus->enabled_fan_curve_profiles.quiet) {
>>  +		curve = asus->gpu_fan_curve.quiet;
>>  +	}
>>  +
>>  +	if (curve != NULL) {
>>  +		err = fan_curve_write(asus, ASUS_WMI_DEVID_GPU_FAN_CURVE, curve);
>>  +		if (err)
>>  +			return err;
>>  +	}
>>  +	return 0;
>>  +}
>>  +
>>  +static ssize_t fan_curve_store(struct asus_wmi *asus, const char 
>> *buf,
>>  +								size_t count, u32 dev, char **curve,
>>  +								char *default_curve)
>>  +{
>>  +    int err;
>>  +
>>  +	/* Allow a user to write "" or " " to erase a curve setting */
>>  +	if (strlen(buf) <= 1 || strcmp(buf, " \n") == 0) {
>>  +		kfree(*curve);
>>  +		*curve = kstrdup(default_curve, GFP_KERNEL);
>>  +		err = throttle_thermal_policy_write(asus);
>>  +		if (err)
>>  +			return err;
>>  +		return count;
>>  +	}
>>  +
>>  +	if (*curve)
>>  +		kfree(*curve);
>>  +    *curve = kstrdup(buf, GFP_KERNEL);
>>  +
>>  +	/* Maybe activate fan curve if in associated mode */
>>  +	err = throttle_thermal_policy_write(asus);
>>  +	if (err) {
>>  +		kfree(*curve);
>>  +		*curve = kstrdup(default_curve, GFP_KERNEL);
>>  +		return err;
>>  +	}
>>  +
>>  +    return count;
>>  +}
>>  +
>>  +/*
>>  + * CPU Fan Curves
>>  +*/
>>  +
>>  +static ssize_t cpu_fan_curve_balanced_show(struct device *dev,
>>  +				   struct device_attribute *attr, char *buf)
>>  +{
>>  +	struct asus_wmi *asus = dev_get_drvdata(dev);
>>  +	return scnprintf(buf, PAGE_SIZE, "%s", 
>> asus->cpu_fan_curve.balanced);
>>  +}
>>  +
>>  +static ssize_t cpu_fan_curve_balanced_store(struct device *dev,
>>  +				    struct device_attribute *attr,
>>  +				    const char *buf, size_t count)
>>  +{
>>  +    struct asus_wmi *asus = dev_get_drvdata(dev);
>>  +    return fan_curve_store(asus, buf, count, 
>> ASUS_WMI_DEVID_CPU_FAN_CURVE,
>>  +							&asus->cpu_fan_curve.balanced,
>>  +							asus->cpu_fan_curve.balanced_default);
>>  +}
>>  +
>>  +static DEVICE_ATTR_RW(cpu_fan_curve_balanced);
>>  +
>>  +static ssize_t cpu_fan_curve_performance_show(struct device *dev,
>>  +				   struct device_attribute *attr, char *buf)
>>  +{
>>  +	struct asus_wmi *asus = dev_get_drvdata(dev);
>>  +	return scnprintf(buf, PAGE_SIZE, "%s", 
>> asus->cpu_fan_curve.performance);
>>  +}
>>  +
>>  +static ssize_t cpu_fan_curve_performance_store(struct device *dev,
>>  +				    struct device_attribute *attr,
>>  +				    const char *buf, size_t count)
>>  +{
>>  +    struct asus_wmi *asus = dev_get_drvdata(dev);
>>  +    return fan_curve_store(asus, buf, count, 
>> ASUS_WMI_DEVID_CPU_FAN_CURVE,
>>  +							&asus->cpu_fan_curve.performance,
>>  +							asus->cpu_fan_curve.performance_default);
>>  +}
>>  +
>>  +static DEVICE_ATTR_RW(cpu_fan_curve_performance);
>>  +
>>  +static ssize_t cpu_fan_curve_quiet_show(struct device *dev,
>>  +				   struct device_attribute *attr, char *buf)
>>  +{
>>  +	struct asus_wmi *asus = dev_get_drvdata(dev);
>>  +	return scnprintf(buf, PAGE_SIZE, "%s", asus->cpu_fan_curve.quiet);
>>  +}
>>  +
>>  +static ssize_t cpu_fan_curve_quiet_store(struct device *dev,
>>  +				    struct device_attribute *attr,
>>  +				    const char *buf, size_t count)
>>  +{
>>  +    struct asus_wmi *asus = dev_get_drvdata(dev);
>>  +    return fan_curve_store(asus, buf, count, 
>> ASUS_WMI_DEVID_CPU_FAN_CURVE,
>>  +							&asus->cpu_fan_curve.quiet,
>>  +							asus->cpu_fan_curve.quiet_default);
>>  +}
>>  +
>>  +static DEVICE_ATTR_RW(cpu_fan_curve_quiet);
>>  +
>>  +/*
>>  + * GPU Fan Curves
>>  +*/
>>  +
>>  +static ssize_t gpu_fan_curve_balanced_show(struct device *dev,
>>  +				   struct device_attribute *attr, char *buf)
>>  +{
>>  +	struct asus_wmi *asus = dev_get_drvdata(dev);
>>  +	return scnprintf(buf, PAGE_SIZE, "%s", 
>> asus->gpu_fan_curve.balanced);
>>  +}
>>  +
>>  +static ssize_t gpu_fan_curve_balanced_store(struct device *dev,
>>  +				    struct device_attribute *attr,
>>  +				    const char *buf, size_t count)
>>  +{
>>  +    struct asus_wmi *asus = dev_get_drvdata(dev);
>>  +    return fan_curve_store(asus, buf, count, 
>> ASUS_WMI_DEVID_GPU_FAN_CURVE,
>>  +							&asus->gpu_fan_curve.balanced,
>>  +							asus->gpu_fan_curve.balanced_default);
>>  +}
>>  +
>>  +static DEVICE_ATTR_RW(gpu_fan_curve_balanced);
>>  +
>>  +static ssize_t gpu_fan_curve_performance_show(struct device *dev,
>>  +				   struct device_attribute *attr, char *buf)
>>  +{
>>  +	struct asus_wmi *asus = dev_get_drvdata(dev);
>>  +	return scnprintf(buf, PAGE_SIZE, "%s", 
>> asus->gpu_fan_curve.performance);
>>  +}
>>  +
>>  +static ssize_t gpu_fan_curve_performance_store(struct device *dev,
>>  +				    struct device_attribute *attr,
>>  +				    const char *buf, size_t count)
>>  +{
>>  +    struct asus_wmi *asus = dev_get_drvdata(dev);
>>  +    return fan_curve_store(asus, buf, count, 
>> ASUS_WMI_DEVID_GPU_FAN_CURVE,
>>  +							&asus->gpu_fan_curve.performance,
>>  +							asus->gpu_fan_curve.performance_default);
>>  +}
>>  +
>>  +static DEVICE_ATTR_RW(gpu_fan_curve_performance);
>>  +
>>  +static ssize_t gpu_fan_curve_quiet_show(struct device *dev,
>>  +				   struct device_attribute *attr, char *buf)
>>  +{
>>  +	struct asus_wmi *asus = dev_get_drvdata(dev);
>>  +	return scnprintf(buf, PAGE_SIZE, "%s", asus->gpu_fan_curve.quiet);
>>  +}
>>  +
>>  +static ssize_t gpu_fan_curve_quiet_store(struct device *dev,
>>  +				    struct device_attribute *attr,
>>  +				    const char *buf, size_t count)
>>  +{
>>  +    struct asus_wmi *asus = dev_get_drvdata(dev);
>>  +    return fan_curve_store(asus, buf, count, 
>> ASUS_WMI_DEVID_GPU_FAN_CURVE,
>>  +							&asus->gpu_fan_curve.quiet,
>>  +							asus->gpu_fan_curve.quiet_default);
>>  +}
>>  +
>>  +static DEVICE_ATTR_RW(gpu_fan_curve_quiet);
> 
> Even though it is a hwmon thing, I think `SENSOR_ATTR_2()` (from 
> linux/hwmon-sysfs.h)
> would be very useful here as you'd avoid creating n+1 functions, e.g:
> 
>   static ssize_t fan_curve_show(struct device *dev, struct 
> device_attribute *attr, char *buf)
>   {
>     struct sensor_device_attribute_2 *sattr = 
> to_sensor_dev_attr_2(attr);
>     struct asus_wmi *asus = dev_get_drvdata(dev);
> 
>     /*
>      * if you stored fan curves in an array, you could then access 
> the fan
>      * curve in `asus->fans[sattr->index].curves[sattr->nr]`
>      * /
>   }
> 
>   static SENSOR_DEVICE_ATTR_2(some_name1, 0644, fan_curve_show, 
> fan_curve_store,
>                               FAN_CPU /* index in the "fans" array */,
>                               ASUS_THROTTLE_THERMAL_POLICY_SILENT /* 
> index in the "curves" array */);
> 

I'm sorry I don't really understand how this works. Is there a good doc 
for it anywhere? Being unfamiliar with C makes it look a little more 
intimidating than what I've managed to do so far.

> 
>>  +
>>  +/*
>>  + * Profiles with enabled fan curve setting
>>  +*/
>>  +
>>  +static int enabled_fan_curve_profiles_write(struct asus_wmi *asus,
>>  +											const char *names)
>>  +{
>>  +    char *buf, *set, *set_end;
>>  +    int err;
>>  +
>>  +    buf = set_end = kstrdup(names, GFP_KERNEL);
>>  +
>>  +	/* Reset before checking */
>>  +	asus->enabled_fan_curve_profiles.balanced = false;
>>  +	asus->enabled_fan_curve_profiles.quiet = false;
>>  +	asus->enabled_fan_curve_profiles.performance = false;
>>  +
>>  +	while( (set = strsep(&set_end, " ")) != NULL ) {
>>  +		if (set == NULL)
> 
> When is this possible?

Uh... Removed XD

> 
> 
>>  +			set = buf;
>>  +
>>  +		if (strcmp(set, "balanced") == 0
>>  +				|| strcmp(set, "balanced\n") == 0)
>>  +			asus->enabled_fan_curve_profiles.balanced = true;
>>  +
>>  +		if (strcmp(set, "quiet") == 0
>>  +				|| strcmp(set, "quiet\n") == 0)
>>  +			asus->enabled_fan_curve_profiles.quiet = true;
>>  +
>>  +		if (strcmp(set, "performance") == 0
>>  +				|| strcmp(set, "performance\n") == 0)
>>  +			asus->enabled_fan_curve_profiles.performance = true;
> 
> If you store the enabled curves in an array, and you have a list of 
> profile names,
> then `sysfs_match_string()`, will be very helpful here. You could do 
> something like:
> 
>   int profile = sysfs_match_string(profile_names, set);
>   if (profile < 0) {
>     /* not found */
>   }
> 
>   asus->fan_curve_enabled_for_profile[profile] = true;

Okay now that's cool. I'll just the relevant parts to use this. Thanks!

> 
> 
>>  +	}
>>  +
>>  +	err = throttle_thermal_policy_write(asus);
>>  +	if (err)
>>  +		return err;
>>  +
>>  +	kfree(buf);
>>  +
>>  +	return 0;
>>  +}
>>  +
>>  +static ssize_t enabled_fan_curve_profiles_show(struct device *dev,
>>  +				   struct device_attribute *attr, char *buf)
>>  +{
>>  +	struct asus_wmi *asus = dev_get_drvdata(dev);
>>  +	int len = 0;
>>  +
>>  +	if (asus->enabled_fan_curve_profiles.balanced)
>>  +		len += sysfs_emit_at(buf, len, "balanced ");
>>  +
>>  +	if (asus->enabled_fan_curve_profiles.performance)
>>  +		len += sysfs_emit_at(buf, len, "performance ");
>>  +
>>  +	if (asus->enabled_fan_curve_profiles.quiet)
>>  +		len += sysfs_emit_at(buf, len, "quiet ");
>>  +
>>  +	len += sysfs_emit_at(buf, len, "\n");
>>  +	return len;
>>  +}
>>  +
>>  +static ssize_t enabled_fan_curve_profiles_store(struct device *dev,
>>  +				    struct device_attribute *attr,
>>  +				    const char *buf, size_t count)
>>  +{
>>  +    struct asus_wmi *asus = dev_get_drvdata(dev);
>>  +	int err;
>>  +
>>  +	err = enabled_fan_curve_profiles_write(asus, buf);
>>  +	if (err)
>>  +		return err;
>>  +
>>  +    return count;
>>  +}
>>  +
>>  +static DEVICE_ATTR_RW(enabled_fan_curve_profiles);
>>  +
>>   /* Throttle thermal policy 
>> ****************************************************/
>> 
>>   static int throttle_thermal_policy_check_present(struct asus_wmi 
>> *asus)
>>  @@ -2092,6 +2652,26 @@ static int 
>> throttle_thermal_policy_write(struct asus_wmi *asus)
>>   		return -EIO;
>>   	}
>> 
>>  +	if (asus->cpu_fan_curve_available) {
>>  +		err = fan_curve_cpu_write(asus);
>>  +		if (err) {
>>  +			dev_warn(&asus->platform_device->dev,
>>  +				"Failed to set custom CPU curve for thermal policy: %d\n",
>>  +				err);
>>  +			return err;
>>  +		}
>>  +	}
>>  +
>>  +	if (asus->gpu_fan_curve_available) {
>>  +		err = fan_curve_gpu_write(asus);
>>  +		if (err) {
>>  +			dev_warn(&asus->platform_device->dev,
>>  +				"Failed to set custom GPU curve for thermal policy: %d\n",
>>  +				err);
>>  +			return err;
>>  +		}
>>  +	}
>>  +
>>   	return 0;
>>   }
>> 
>>  @@ -2711,6 +3291,13 @@ static struct attribute 
>> *platform_attributes[] = {
>>   	&dev_attr_als_enable.attr,
>>   	&dev_attr_fan_boost_mode.attr,
>>   	&dev_attr_throttle_thermal_policy.attr,
>>  +	&dev_attr_cpu_fan_curve_balanced.attr,
>>  +	&dev_attr_cpu_fan_curve_performance.attr,
>>  +	&dev_attr_cpu_fan_curve_quiet.attr,
>>  +    &dev_attr_gpu_fan_curve_balanced.attr,
>>  +	&dev_attr_gpu_fan_curve_performance.attr,
>>  +	&dev_attr_gpu_fan_curve_quiet.attr,
>>  +	&dev_attr_enabled_fan_curve_profiles.attr,
>>   	&dev_attr_panel_od.attr,
>>   	NULL
>>   };
>>  @@ -2741,6 +3328,20 @@ static umode_t asus_sysfs_is_visible(struct 
>> kobject *kobj,
>>   		ok = asus->fan_boost_mode_available;
>>   	else if (attr == &dev_attr_throttle_thermal_policy.attr)
>>   		ok = asus->throttle_thermal_policy_available;
>>  +	else if (attr == &dev_attr_cpu_fan_curve_balanced.attr)
>>  +		ok = asus->cpu_fan_curve_available;
>>  +	else if (attr == &dev_attr_cpu_fan_curve_performance.attr)
>>  +		ok = asus->cpu_fan_curve_available;
>>  +	else if (attr == &dev_attr_cpu_fan_curve_quiet.attr)
>>  +		ok = asus->cpu_fan_curve_available;
>>  +    else if (attr == &dev_attr_gpu_fan_curve_balanced.attr)
>>  +		ok = asus->gpu_fan_curve_available;
>>  +	else if (attr == &dev_attr_gpu_fan_curve_performance.attr)
>>  +		ok = asus->gpu_fan_curve_available;
>>  +	else if (attr == &dev_attr_gpu_fan_curve_quiet.attr)
>>  +		ok = asus->gpu_fan_curve_available;
>>  +	else if (attr == &dev_attr_enabled_fan_curve_profiles.attr)
>>  +		ok = asus->cpu_fan_curve_available || 
>> asus->gpu_fan_curve_available;
>>   	else if (attr == &dev_attr_panel_od.attr)
>>   		ok = asus->panel_overdrive_available;
>> 
>>  @@ -3016,6 +3617,16 @@ static int asus_wmi_add(struct 
>> platform_device *pdev)
>>   	else
>>   		throttle_thermal_policy_set_default(asus);
>> 
>>  +	err = custom_fan_check_present(asus, 
>> &asus->cpu_fan_curve_available,
>>  +			ASUS_WMI_DEVID_CPU_FAN_CURVE);
>>  +	if (err)
>>  +		goto fail_custom_fan_curve;
>>  +
>>  +    err = custom_fan_check_present(asus, 
>> &asus->gpu_fan_curve_available,
>>  +			ASUS_WMI_DEVID_GPU_FAN_CURVE);
>>  +	if (err)
>>  +		goto fail_custom_fan_curve;
>>  +
>>   	err = platform_profile_setup(asus);
>>   	if (err)
>>   		goto fail_platform_profile_setup;
>>  @@ -3109,6 +3720,7 @@ static int asus_wmi_add(struct 
>> platform_device *pdev)
>>   	asus_wmi_sysfs_exit(asus->platform_device);
>>   fail_sysfs:
>>   fail_throttle_thermal_policy:
>>  +fail_custom_fan_curve:
>>   fail_platform_profile_setup:
>>   	if (asus->platform_profile_support)
>>   		platform_profile_remove();
>>  diff --git a/include/linux/platform_data/x86/asus-wmi.h 
>> b/include/linux/platform_data/x86/asus-wmi.h
>>  index 17dc5cb6f3f2..a571b47ff362 100644
>>  --- a/include/linux/platform_data/x86/asus-wmi.h
>>  +++ b/include/linux/platform_data/x86/asus-wmi.h
>>  @@ -77,6 +77,8 @@
>>   #define ASUS_WMI_DEVID_THERMAL_CTRL	0x00110011
>>   #define ASUS_WMI_DEVID_FAN_CTRL		0x00110012 /* deprecated */
>>   #define ASUS_WMI_DEVID_CPU_FAN_CTRL	0x00110013
>>  +#define ASUS_WMI_DEVID_CPU_FAN_CURVE	0x00110024
>>  +#define ASUS_WMI_DEVID_GPU_FAN_CURVE	0x00110025
>> 
>>   /* Power */
>>   #define ASUS_WMI_DEVID_PROCESSOR_STATE	0x00120012
>>  --
>>  2.31.1
> 
> 
> Best regards,
> Barnabás Pőcze

Re: [PATCH v5] asus-wmi: Add support for custom fan curves

[Barnabás Pőcze]

Hi


2021. augusztus 28., szombat 8:56 keltezéssel, Luke Jones írta:
> [...]
> >>  +/*
> >>  + * The expected input is of the format
> >>  + *     "30:1,49:2,59:3,69:4,79:31,89:49,99:56,109:58"
> >>  + * where a pair is 30:1, with 30 = temperature, and 1 = percentage
> >>  +*/
> >>  +static int fan_curve_write(struct asus_wmi *asus, u32 dev, char
> >> *curve)
> >>  +{
> >>  +    char * buf, *set, *pair_tmp, *pair, *set_end, *pair_end;
> >>  +    int err, ret;
> >>  +
> >>  +	char *set_delimiter = ",";
> >>  +	char *pair_delimiter = ":";
> >>  +	bool half_complete = false;
> >>  +	bool pair_start = true;
> >>  +	u32 prev_percent = 0;
> >>  +	u32 prev_temp = 0;
> >>  +	u32 percent = 0;
> >>  +	u32 shift = 0;
> >>  +	u32 temp = 0;
> >>  +    u32 arg1 = 0;
> >>  +    u32 arg2 = 0;
> >>  +    u32 arg3 = 0;
> >>  +    u32 arg4 = 0;
> >>  +
> >>  +    buf = set_end = pair_end = kstrdup(curve, GFP_KERNEL);
> >>  +
> >>  +	while( (set = strsep(&set_end, set_delimiter)) != NULL ) {
> >>  +		pair_tmp = kstrdup(set, GFP_KERNEL);
> >>  +        pair_start = true;
> >>  +		while( (pair = strsep(&pair_tmp, pair_delimiter)) != NULL ) {
> >>  +			err = kstrtouint(pair, 10, &ret);
> >>  +            if (err) {
> >>  +                kfree(pair_tmp);
> >>  +                kfree(buf);
> >>  +                return err;
> >>  +            }
> >>  +
> >>  +            if (pair_start) {
> >>  +                temp = ret;
> >>  +                pair_start = false;
> >>  +            } else {
> >>  +                percent = ret;
> >>  +            }
> >>  +		}
> >>  +		kfree(pair_tmp);
> >>  +
> >>  +		if (temp < prev_temp || percent < prev_percent || percent > 100)
> >> {
> >>  +            pr_info("Fan curve invalid");
> >>  +			pr_info("A value is sequentially lower or percentage is > 100");
> >>  +            kfree(buf);
> >>  +            return -EINVAL;
> >>  +        }
> >>  +
> >>  +        prev_temp = temp;
> >>  +        prev_percent = percent;
> >>  +
> >>  +        if (!half_complete) {
> >>  +            arg1 += temp << shift;
> >>  +            arg3 += percent << shift;
> >>  +        } else {
> >>  +            arg2 += temp << shift;
> >>  +            arg4 += percent << shift;
> >>  +        }
> >
> > As far as I see using 64-bit integers would avoid the need for
> > `half_complete`, et al.
>
> Reworked all that as part of the u8-array stuff. Look forward to seeing
> what you think.
>
> >
> >
> >>  +        shift += 8;
> >>  +
> >>  +        if (shift == 32) {
> >>  +            shift = 0;
> >>  +            half_complete = true;
> >>  +        }
> >>  +	}
> >>  +	kfree(buf);
> >>  +
> >
> > If you don't insist on using commas, I think it is much simpler to
> > parse it using `sscanf()`, e.g.:
> >
> >   unsigned int temp, prct;
> >   int at = 0, len;
> >
> >   while (sscanf(&buf[at], "%u:%u %n", &temp, &prct, &len) == 2) {
> >     /* process `temp` and `prct` */
> >
> >     at += len;
> >   }
> >
> >   if (buf[at] != '\0')
> >     /* error */;
> >
> > This also has the advantage that you don't need dynamic memory
> > allocation.
>
> Half the reason I did it in the format of 10:20,30:40,.. is to keep
> close to a format that many people using some external tools for fan
> curves (using acpi_call modue!) are using. I'm open to improvements ofc.
>

If you don't insist on *requiring* commas, then I think the following works:

  while (sscanf(&buf[at], "%u:%u %n", &temp, &prct, &len) == 2) {
    /* process `temp` and `prct` */

    at += len;
    at += strspn(&buf[at], ",");
  }

But please, whatever parser you end up submitting, make sure it is thoroughly tested.


> [...]
> >>  +static ssize_t gpu_fan_curve_quiet_show(struct device *dev,
> >>  +				   struct device_attribute *attr, char *buf)
> >>  +{
> >>  +	struct asus_wmi *asus = dev_get_drvdata(dev);
> >>  +	return scnprintf(buf, PAGE_SIZE, "%s", asus->gpu_fan_curve.quiet);
> >>  +}
> >>  +
> >>  +static ssize_t gpu_fan_curve_quiet_store(struct device *dev,
> >>  +				    struct device_attribute *attr,
> >>  +				    const char *buf, size_t count)
> >>  +{
> >>  +    struct asus_wmi *asus = dev_get_drvdata(dev);
> >>  +    return fan_curve_store(asus, buf, count,
> >> ASUS_WMI_DEVID_GPU_FAN_CURVE,
> >>  +							&asus->gpu_fan_curve.quiet,
> >>  +							asus->gpu_fan_curve.quiet_default);
> >>  +}
> >>  +
> >>  +static DEVICE_ATTR_RW(gpu_fan_curve_quiet);
> >
> > Even though it is a hwmon thing, I think `SENSOR_ATTR_2()` (from
> > linux/hwmon-sysfs.h)
> > would be very useful here as you'd avoid creating n+1 functions, e.g:
> >
> >   static ssize_t fan_curve_show(struct device *dev, struct
> > device_attribute *attr, char *buf)
> >   {
> >     struct sensor_device_attribute_2 *sattr =
> > to_sensor_dev_attr_2(attr);
> >     struct asus_wmi *asus = dev_get_drvdata(dev);
> >
> >     /*
> >      * if you stored fan curves in an array, you could then access
> > the fan
> >      * curve in `asus->fans[sattr->index].curves[sattr->nr]`
> >      * /
> >   }
> >
> >   static SENSOR_DEVICE_ATTR_2(some_name1, 0644, fan_curve_show,
> > fan_curve_store,
> >                               FAN_CPU /* index in the "fans" array */,
> >                               ASUS_THROTTLE_THERMAL_POLICY_SILENT /*
> > index in the "curves" array */);
> >
>
> I'm sorry I don't really understand how this works. Is there a good doc
> for it anywhere? Being unfamiliar with C makes it look a little more
> intimidating than what I've managed to do so far.
>

I am not sure, you can find some uses among hwmon drivers.

If you look into linux/hwmon-sysfs.h, then you can see that `SENSOR_DEVICE_ATTR_2()`
defines and initializes a `struct sensor_device_attribute_2` object:

  struct sensor_device_attribute_2 {
    struct device_attribute dev_attr;
    u8 index;
    u8 nr;
  };

So it has a normal device attribute inside it, and two extra pieces of data.
One difference is that when you create the `struct attribute` array
(`platform_attributes`), then you will need to use `&some_name1.dev_attr.attr`.

And the idea here is that the show/store callbacks receive a pointer to the
device attribute that is being read/written, and we know for a fact, that this
device attribute is inside a `sensor_device_attribute_2` struct. And thus we can
use the `to_sensor_dev_attr_2()` macro to get a pointer to the "outer"
`sensor_device_attribute_2` struct that contains the `device_attribute` struct
that we have a pointer to.

So now the `index` and `nr` members of that struct can be accessed. You could
store the index of the fan (e.g. 0 for CPU, 1 for GPU) in `index`, and the profile
in `nr`. The `ASUS_THROTTLE_THERMAL_POLICY_*` macros go from 0 to 2, so I think
those would be perfect candidates for the curve index. That's why I used
`ASUS_THROTTLE_THERMAL_POLICY_SILENT` in the example.

The fan curve associated with the attribute can now be
accessed in `asus->fans[sattr->index].curves[sattr->nr]`.

`to_sensor_dev_attr_2()` is just a wrapper around `container_of()`, so if you're
familiar with the idea behind that, this shouldn't be too hard to wrap your
head around.

  #define to_sensor_dev_attr_2(_dev_attr) \
    container_of(_dev_attr, struct sensor_device_attribute_2, dev_attr)

What it does, is that if you give it a pointer to the `dev_attr` member of a
`struct sensor_device_attribute_2`, then it'll give you back a pointer
to the `struct sensor_device_attribute_2`. `container_of()` basically does a
"conversion" from pointer-to-member-of-struct-X to pointer-to-struct-X.

In some sense, you might think of `struct device_attribute` as the "base class",
and the `struct sensor_device_attribute_2` as the "derived class" here. And what
`to_sensor_dev_attr_2()` is a down-cast from the base class to the derived,
e.g. something like this in C++:

  struct device_attribute { ... };
  struct sensor_device_attribute_2 : device_attribute {
    u8 index;
    u8 nr;
  };

  /* `device_attr` is of type `struct device_attribute *` */
  static_cast<sensor_device_attribute_2 *>(device_attr);
  /* there's also dynamic_cast which can do the same down-cast,
     but it does runtime type checking as well */
  /* both of the mentioned C++ casts check if the pointer is nullptr,
     normal container_of() does not that, but there is container_of_safe() */

It may be too detailed, I'm not sure; please let me know if you have other questions.


> [...]


Best regards,
Barnabás Pőcze

Re: [PATCH v5] asus-wmi: Add support for custom fan curves

[Luke Jones]

Thanks heaps Barnabás, I think I've gotten a very good improvement 
with your help. Let's see how V6 fairs.

On Sat, Aug 28 2021 at 14:39:40 +0000, Barnabás Pőcze 
<pobrn@protonmail.com> wrote:
> Hi
> 
> 
> 2021. augusztus 28., szombat 8:56 keltezéssel, Luke Jones írta:
>>  [...]
>>  >>  +/*
>>  >>  + * The expected input is of the format
>>  >>  + *     "30:1,49:2,59:3,69:4,79:31,89:49,99:56,109:58"
>>  >>  + * where a pair is 30:1, with 30 = temperature, and 1 = 
>> percentage
>>  >>  +*/
>>  >>  +static int fan_curve_write(struct asus_wmi *asus, u32 dev, char
>>  >> *curve)
>>  >>  +{
>>  >>  +    char * buf, *set, *pair_tmp, *pair, *set_end, *pair_end;
>>  >>  +    int err, ret;
>>  >>  +
>>  >>  +	char *set_delimiter = ",";
>>  >>  +	char *pair_delimiter = ":";
>>  >>  +	bool half_complete = false;
>>  >>  +	bool pair_start = true;
>>  >>  +	u32 prev_percent = 0;
>>  >>  +	u32 prev_temp = 0;
>>  >>  +	u32 percent = 0;
>>  >>  +	u32 shift = 0;
>>  >>  +	u32 temp = 0;
>>  >>  +    u32 arg1 = 0;
>>  >>  +    u32 arg2 = 0;
>>  >>  +    u32 arg3 = 0;
>>  >>  +    u32 arg4 = 0;
>>  >>  +
>>  >>  +    buf = set_end = pair_end = kstrdup(curve, GFP_KERNEL);
>>  >>  +
>>  >>  +	while( (set = strsep(&set_end, set_delimiter)) != NULL ) {
>>  >>  +		pair_tmp = kstrdup(set, GFP_KERNEL);
>>  >>  +        pair_start = true;
>>  >>  +		while( (pair = strsep(&pair_tmp, pair_delimiter)) != NULL ) {
>>  >>  +			err = kstrtouint(pair, 10, &ret);
>>  >>  +            if (err) {
>>  >>  +                kfree(pair_tmp);
>>  >>  +                kfree(buf);
>>  >>  +                return err;
>>  >>  +            }
>>  >>  +
>>  >>  +            if (pair_start) {
>>  >>  +                temp = ret;
>>  >>  +                pair_start = false;
>>  >>  +            } else {
>>  >>  +                percent = ret;
>>  >>  +            }
>>  >>  +		}
>>  >>  +		kfree(pair_tmp);
>>  >>  +
>>  >>  +		if (temp < prev_temp || percent < prev_percent || percent > 
>> 100)
>>  >> {
>>  >>  +            pr_info("Fan curve invalid");
>>  >>  +			pr_info("A value is sequentially lower or percentage is > 
>> 100");
>>  >>  +            kfree(buf);
>>  >>  +            return -EINVAL;
>>  >>  +        }
>>  >>  +
>>  >>  +        prev_temp = temp;
>>  >>  +        prev_percent = percent;
>>  >>  +
>>  >>  +        if (!half_complete) {
>>  >>  +            arg1 += temp << shift;
>>  >>  +            arg3 += percent << shift;
>>  >>  +        } else {
>>  >>  +            arg2 += temp << shift;
>>  >>  +            arg4 += percent << shift;
>>  >>  +        }
>>  >
>>  > As far as I see using 64-bit integers would avoid the need for
>>  > `half_complete`, et al.
>> 
>>  Reworked all that as part of the u8-array stuff. Look forward to 
>> seeing
>>  what you think.
>> 
>>  >
>>  >
>>  >>  +        shift += 8;
>>  >>  +
>>  >>  +        if (shift == 32) {
>>  >>  +            shift = 0;
>>  >>  +            half_complete = true;
>>  >>  +        }
>>  >>  +	}
>>  >>  +	kfree(buf);
>>  >>  +
>>  >
>>  > If you don't insist on using commas, I think it is much simpler to
>>  > parse it using `sscanf()`, e.g.:
>>  >
>>  >   unsigned int temp, prct;
>>  >   int at = 0, len;
>>  >
>>  >   while (sscanf(&buf[at], "%u:%u %n", &temp, &prct, &len) == 2) {
>>  >     /* process `temp` and `prct` */
>>  >
>>  >     at += len;
>>  >   }
>>  >
>>  >   if (buf[at] != '\0')
>>  >     /* error */;
>>  >
>>  > This also has the advantage that you don't need dynamic memory
>>  > allocation.
>> 
>>  Half the reason I did it in the format of 10:20,30:40,.. is to keep
>>  close to a format that many people using some external tools for fan
>>  curves (using acpi_call modue!) are using. I'm open to improvements 
>> ofc.
>> 
> 
> If you don't insist on *requiring* commas, then I think the following 
> works:
> 
>   while (sscanf(&buf[at], "%u:%u %n", &temp, &prct, &len) == 2) {
>     /* process `temp` and `prct` */
> 
>     at += len;
>     at += strspn(&buf[at], ",");
>   }
> 
> But please, whatever parser you end up submitting, make sure it is 
> thoroughly tested.
> 
> 
>>  [...]
>>  >>  +static ssize_t gpu_fan_curve_quiet_show(struct device *dev,
>>  >>  +				   struct device_attribute *attr, char *buf)
>>  >>  +{
>>  >>  +	struct asus_wmi *asus = dev_get_drvdata(dev);
>>  >>  +	return scnprintf(buf, PAGE_SIZE, "%s", 
>> asus->gpu_fan_curve.quiet);
>>  >>  +}
>>  >>  +
>>  >>  +static ssize_t gpu_fan_curve_quiet_store(struct device *dev,
>>  >>  +				    struct device_attribute *attr,
>>  >>  +				    const char *buf, size_t count)
>>  >>  +{
>>  >>  +    struct asus_wmi *asus = dev_get_drvdata(dev);
>>  >>  +    return fan_curve_store(asus, buf, count,
>>  >> ASUS_WMI_DEVID_GPU_FAN_CURVE,
>>  >>  +							&asus->gpu_fan_curve.quiet,
>>  >>  +							asus->gpu_fan_curve.quiet_default);
>>  >>  +}
>>  >>  +
>>  >>  +static DEVICE_ATTR_RW(gpu_fan_curve_quiet);
>>  >
>>  > Even though it is a hwmon thing, I think `SENSOR_ATTR_2()` (from
>>  > linux/hwmon-sysfs.h)
>>  > would be very useful here as you'd avoid creating n+1 functions, 
>> e.g:
>>  >
>>  >   static ssize_t fan_curve_show(struct device *dev, struct
>>  > device_attribute *attr, char *buf)
>>  >   {
>>  >     struct sensor_device_attribute_2 *sattr =
>>  > to_sensor_dev_attr_2(attr);
>>  >     struct asus_wmi *asus = dev_get_drvdata(dev);
>>  >
>>  >     /*
>>  >      * if you stored fan curves in an array, you could then access
>>  > the fan
>>  >      * curve in `asus->fans[sattr->index].curves[sattr->nr]`
>>  >      * /
>>  >   }
>>  >
>>  >   static SENSOR_DEVICE_ATTR_2(some_name1, 0644, fan_curve_show,
>>  > fan_curve_store,
>>  >                               FAN_CPU /* index in the "fans" 
>> array */,
>>  >                               ASUS_THROTTLE_THERMAL_POLICY_SILENT 
>> /*
>>  > index in the "curves" array */);
>>  >
>> 
>>  I'm sorry I don't really understand how this works. Is there a good 
>> doc
>>  for it anywhere? Being unfamiliar with C makes it look a little more
>>  intimidating than what I've managed to do so far.
>> 
> 
> I am not sure, you can find some uses among hwmon drivers.
> 
> If you look into linux/hwmon-sysfs.h, then you can see that 
> `SENSOR_DEVICE_ATTR_2()`
> defines and initializes a `struct sensor_device_attribute_2` object:
> 
>   struct sensor_device_attribute_2 {
>     struct device_attribute dev_attr;
>     u8 index;
>     u8 nr;
>   };
> 
> So it has a normal device attribute inside it, and two extra pieces 
> of data.
> One difference is that when you create the `struct attribute` array
> (`platform_attributes`), then you will need to use 
> `&some_name1.dev_attr.attr`.
> 
> And the idea here is that the show/store callbacks receive a pointer 
> to the
> device attribute that is being read/written, and we know for a fact, 
> that this
> device attribute is inside a `sensor_device_attribute_2` struct. And 
> thus we can
> use the `to_sensor_dev_attr_2()` macro to get a pointer to the "outer"
> `sensor_device_attribute_2` struct that contains the 
> `device_attribute` struct
> that we have a pointer to.
> 
> So now the `index` and `nr` members of that struct can be accessed. 
> You could
> store the index of the fan (e.g. 0 for CPU, 1 for GPU) in `index`, 
> and the profile
> in `nr`. The `ASUS_THROTTLE_THERMAL_POLICY_*` macros go from 0 to 2, 
> so I think
> those would be perfect candidates for the curve index. That's why I 
> used
> `ASUS_THROTTLE_THERMAL_POLICY_SILENT` in the example.
> 
> The fan curve associated with the attribute can now be
> accessed in `asus->fans[sattr->index].curves[sattr->nr]`.
> 
> `to_sensor_dev_attr_2()` is just a wrapper around `container_of()`, 
> so if you're
> familiar with the idea behind that, this shouldn't be too hard to 
> wrap your
> head around.
> 
>   #define to_sensor_dev_attr_2(_dev_attr) \
>     container_of(_dev_attr, struct sensor_device_attribute_2, 
> dev_attr)
> 
> What it does, is that if you give it a pointer to the `dev_attr` 
> member of a
> `struct sensor_device_attribute_2`, then it'll give you back a pointer
> to the `struct sensor_device_attribute_2`. `container_of()` basically 
> does a
> "conversion" from pointer-to-member-of-struct-X to 
> pointer-to-struct-X.
> 
> In some sense, you might think of `struct device_attribute` as the 
> "base class",
> and the `struct sensor_device_attribute_2` as the "derived class" 
> here. And what
> `to_sensor_dev_attr_2()` is a down-cast from the base class to the 
> derived,
> e.g. something like this in C++:
> 
>   struct device_attribute { ... };
>   struct sensor_device_attribute_2 : device_attribute {
>     u8 index;
>     u8 nr;
>   };
> 
>   /* `device_attr` is of type `struct device_attribute *` */
>   static_cast<sensor_device_attribute_2 *>(device_attr);
>   /* there's also dynamic_cast which can do the same down-cast,
>      but it does runtime type checking as well */
>   /* both of the mentioned C++ casts check if the pointer is nullptr,
>      normal container_of() does not that, but there is 
> container_of_safe() */
> 
> It may be too detailed, I'm not sure; please let me know if you have 
> other questions.
> 
> 
>>  [...]
> 
> 
> Best regards,
> Barnabás Pőcze