From: Guenter Roeck <linux@roeck-us.net>
Date: Tue, 26 Feb 2013 07:18:12 +0000 (-0800)
Subject: nct6775: Don't report VID if not supported
X-Git-Tag: nct6775-v0.9.1~4
X-Git-Url: https://git.sur5r.net/?p=groeck-nct6775;a=commitdiff_plain;h=2aeb0c9f69db6faa7171ad36ab7af7c650370059

nct6775: Don't report VID if not supported

VID support is configured with CR2a on NCT6775 and NCT6776, so we can detect
if it is enabled. NCT6779 does not support VID at all.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---

diff --git a/nct6775.c b/nct6775.c
index 955c7fb..8ac2477 100644
--- a/nct6775.c
+++ b/nct6775.c
@@ -3401,6 +3401,8 @@ static int nct6775_probe(struct platform_device *pdev)
 	const u16 *reg_temp, *reg_temp_over, *reg_temp_hyst, *reg_temp_config;
 	const u16 *reg_temp_alternate, *reg_temp_crit;
 	int num_reg_temp;
+	bool have_vid = false;
+	u8 cr2a;
 
 	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
 	if (!devm_request_region(&pdev->dev, res->start, IOREGION_LENGTH,
@@ -3769,17 +3771,31 @@ static int nct6775_probe(struct platform_device *pdev)
 	/* Initialize the chip */
 	nct6775_init_device(data);
 
-	data->vrm = vid_which_vrm();
 	err = superio_enter(sio_data->sioreg);
 	if (err)
 		return err;
 
+	cr2a = superio_inb(sio_data->sioreg, 0x2a);
+	switch (data->kind) {
+	case nct6775:
+		have_vid = (cr2a & 0x40);
+		break;
+	case nct6776:
+		have_vid = (cr2a & 0x60) == 0x40;
+		break;
+	case nct6779:
+		break;
+	}
+
 	/*
 	 * Read VID value
 	 * We can get the VID input values directly at logical device D 0xe3.
 	 */
-	superio_select(sio_data->sioreg, NCT6775_LD_VID);
-	data->vid = superio_inb(sio_data->sioreg, 0xe3);
+	if (have_vid) {
+		superio_select(sio_data->sioreg, NCT6775_LD_VID);
+		data->vid = superio_inb(sio_data->sioreg, 0xe3);
+		data->vrm = vid_which_vrm();
+	}
 
 	if (fan_debounce) {
 		u8 tmp;
@@ -3804,9 +3820,11 @@ static int nct6775_probe(struct platform_device *pdev)
 
 	superio_exit(sio_data->sioreg);
 
-	err = device_create_file(dev, &dev_attr_cpu0_vid);
-	if (err)
-		return err;
+	if (have_vid) {
+		err = device_create_file(dev, &dev_attr_cpu0_vid);
+		if (err)
+			return err;
+	}
 
 	err = nct6775_check_fan_inputs(sio_data, data);
 	if (err)