[PATCH 3/3] platform/x86 asus-wmi: Add GPU fan reading support

[Vasiliy Kupriakov <rublag-ns@xxxxxxxxx>]

The GPU fan interface is same as the CPU fan, so it is straightforward.

Signed-off-by: Vasiliy Kupriakov <rublag-ns@xxxxxxxxx>
---
 drivers/platform/x86/asus-wmi.c            | 43 ++++++++++++++++++++++
 include/linux/platform_data/x86/asus-wmi.h |  1 +
 2 files changed, 44 insertions(+)

diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c
index 82505307ec17..07508c4d1a9a 100644
--- a/drivers/platform/x86/asus-wmi.c
+++ b/drivers/platform/x86/asus-wmi.c
@@ -71,6 +71,8 @@ MODULE_LICENSE("GPL");
 #define ASUS_FAN_SFUN_READ		0x06
 #define ASUS_FAN_SFUN_WRITE		0x07
 
+#define ASUS_GPU_FAN_DESC		"gpu_fan"
+
 /* Based on standard hwmon pwmX_enable values */
 #define ASUS_FAN_CTRL_FULLSPEED		0
 #define ASUS_FAN_CTRL_MANUAL		1
@@ -201,6 +203,7 @@ struct asus_wmi {
 	enum fan_type fan_type;
 	int fan_pwm_mode;
 	int agfn_pwm;
+	bool gpu_fan_available;
 
 	bool fan_boost_mode_available;
 	u8 fan_boost_mode_mask;
@@ -1546,6 +1549,29 @@ static ssize_t fan1_label_show(struct device *dev,
 	return sprintf(buf, "%s\n", ASUS_FAN_DESC);
 }
 
+static ssize_t fan2_input_show(struct device *dev,
+				  struct device_attribute *attr,
+				  char *buf)
+{
+	struct asus_wmi *asus = dev_get_drvdata(dev);
+	int value;
+	int ret;
+
+	ret = asus_wmi_get_devstate(asus, ASUS_WMI_DEVID_GPU_FAN_CTRL, &value);
+	if (ret < 0)
+		return ret;
+
+	value &= 0xFFFF;
+	return sprintf(buf, "%d\n", value < 0 ? -1 : value * 100);
+}
+
+static ssize_t fan2_label_show(struct device *dev,
+					  struct device_attribute *attr,
+					  char *buf)
+{
+	return sprintf(buf, "%s\n", ASUS_GPU_FAN_DESC);
+}
+
 static ssize_t asus_hwmon_temp1(struct device *dev,
 				struct device_attribute *attr,
 				char *buf)
@@ -1568,6 +1594,10 @@ static DEVICE_ATTR_RW(pwm1_enable);
 static DEVICE_ATTR_RO(fan1_input);
 static DEVICE_ATTR_RO(fan1_label);
 
+/* GPU fan */
+static DEVICE_ATTR_RO(fan2_input);
+static DEVICE_ATTR_RO(fan2_label);
+
 /* Temperature */
 static DEVICE_ATTR(temp1_input, S_IRUGO, asus_hwmon_temp1, NULL);
 
@@ -1577,6 +1607,9 @@ static struct attribute *hwmon_attributes[] = {
 	&dev_attr_fan1_input.attr,
 	&dev_attr_fan1_label.attr,
 
+	&dev_attr_fan2_input.attr,
+	&dev_attr_fan2_label.attr,
+
 	&dev_attr_temp1_input.attr,
 	NULL
 };
@@ -1596,6 +1629,10 @@ static umode_t asus_hwmon_sysfs_is_visible(struct kobject *kobj,
 	    || attr == &dev_attr_pwm1_enable.attr) {
 		if (asus->fan_type == FAN_TYPE_NONE)
 			return 0;
+	} else if (attr == &dev_attr_fan2_input.attr
+	    || attr == &dev_attr_fan2_label.attr) {
+		if (!asus->gpu_fan_available)
+			return 0;
 	} else if (attr == &dev_attr_temp1_input.attr) {
 		int err = asus_wmi_get_devstate(asus,
 						ASUS_WMI_DEVID_THERMAL_CTRL,
@@ -1640,6 +1677,7 @@ static int asus_wmi_fan_init(struct asus_wmi *asus)
 {
 	asus->fan_type = FAN_TYPE_NONE;
 	asus->agfn_pwm = -1;
+	asus->gpu_fan_available = false;
 
 	if (asus_wmi_dev_is_present(asus, ASUS_WMI_DEVID_CPU_FAN_CTRL))
 		asus->fan_type = FAN_TYPE_SPEC83;
@@ -1653,6 +1691,11 @@ static int asus_wmi_fan_init(struct asus_wmi *asus)
 
 	asus_fan_set_auto(asus);
 	asus->fan_pwm_mode = ASUS_FAN_CTRL_AUTO;
+
+	if (asus->fan_type == FAN_TYPE_SPEC83 &&
+	    asus_wmi_has_fan(asus, ASUS_WMI_DEVID_GPU_FAN_CTRL))
+		asus->gpu_fan_available = true;
+
 	return 0;
 }
 
diff --git a/include/linux/platform_data/x86/asus-wmi.h b/include/linux/platform_data/x86/asus-wmi.h
index 897b8332a39f..c0364ba63813 100644
--- a/include/linux/platform_data/x86/asus-wmi.h
+++ b/include/linux/platform_data/x86/asus-wmi.h
@@ -75,6 +75,7 @@
 #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_GPU_FAN_CTRL	0x00110014
 
 /* Power */
 #define ASUS_WMI_DEVID_PROCESSOR_STATE	0x00120012
-- 
2.28.0