hwmon: (dell-smm) Blacklist Dell Studio XPS 8100

commit a4b45b25 upstream.

CPU fan speed going up and down on Dell Studio XPS 8100 for
unknown reasons. Without further debugging on the affected
machine, it is not possible to find the problem.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=100121Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Tested-by: Jan C Peters <jcpeters89@gmail.com>
[groeck: cleaned up description, comments]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/char/i8k.c

@@ -900,6 +900,21 @@ static struct dmi_system_id i8k_dmi_table[] __initdata = {
 
 MODULE_DEVICE_TABLE(dmi, i8k_dmi_table);
 
+static struct dmi_system_id i8k_blacklist_dmi_table[] __initdata = {
+	{
+		/*
+		 * CPU fan speed going up and down on Dell Studio XPS 8100
+		 * for unknown reasons.
+		 */
+		.ident = "Dell Studio XPS 8100",
+		.matches = {
+			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Studio XPS 8100"),
+		},
+	},
+	{ }
+};
+
 /*
  * Probe for the presence of a supported laptop.
  */
@@ -911,7 +926,8 @@ static int __init i8k_probe(void)
 	/*
 	 * Get DMI information
 	 */
-	if (!dmi_check_system(i8k_dmi_table)) {
+	if (!dmi_check_system(i8k_dmi_table) ||
+	    dmi_check_system(i8k_blacklist_dmi_table)) {
 		if (!ignore_dmi && !force)
 			return -ENODEV;