commit e551b15250bfb25ed9a136496e8bfde921194ea1
author Guenter Roeck <linux@roeck-us.net> Sat Dec 14 09:30:20 2013 -0800
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> Wed Dec 18 16:47:05 2013 -0800
tree 70539f3a4fc8117c16b3f274f89478946c1305d6
parent 26d093821f41030feee88e0150fbfb5550e8edce

i8k: Stop reading SMM BIOS version during driver probe

This doesn't work on Studio, XPS, Vostro, and Precision laptops,
and it doesn't provide any value except to cause confusion when
it does not work. Drop it and always use DMI BIOS version instead.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/char/i8k.c

diff --git a/drivers/char/i8k.c b/drivers/char/i8k.c
index 889b87b..216b690 100644
--- a/drivers/char/i8k.c
+++ b/drivers/char/i8k.c
@@ -44,7 +44,6 @@
 #define I8K_SMM_GET_TEMP	0x10a3
 #define I8K_SMM_GET_DELL_SIG1	0xfea3
 #define I8K_SMM_GET_DELL_SIG2	0xffa3
-#define I8K_SMM_BIOS_VERSION	0x00a6
 
 #define I8K_FAN_MULT		30
 #define I8K_MAX_TEMP		127
@@ -208,17 +207,6 @@
 }
 
 /*
- * Read the bios version. Return the version as an integer corresponding
- * to the ascii value, for example "A17" is returned as 0x00413137.
- */
-static int i8k_get_bios_version(void)
-{
-	struct smm_regs regs = { .eax = I8K_SMM_BIOS_VERSION, };
-
-	return i8k_smm(&regs) ? : regs.eax;
-}
-
-/*
  * Read the Fn key status.
  */
 static int i8k_get_fn_status(void)
@@ -355,7 +343,8 @@
 
 	switch (cmd) {
 	case I8K_BIOS_VERSION:
-		val = i8k_get_bios_version();
+		val = (bios_version[0] << 16) |
+				(bios_version[1] << 8) | bios_version[2];
 		break;
 
 	case I8K_MACHINE_ID:
@@ -717,8 +706,6 @@
  */
 static int __init i8k_probe(void)
 {
-	char buff[4];
-	int version;
 	const struct dmi_system_id *id;
 
 	/*
@@ -748,31 +735,6 @@
 			return -ENODEV;
 	}
 
-	/*
-	 * Get SMM BIOS version.
-	 */
-	version = i8k_get_bios_version();
-	if (version <= 0) {
-		pr_warn("unable to get SMM BIOS version\n");
-	} else {
-		buff[0] = (version >> 16) & 0xff;
-		buff[1] = (version >> 8) & 0xff;
-		buff[2] = (version) & 0xff;
-		buff[3] = '\0';
-		/*
-		 * If DMI BIOS version is unknown use SMM BIOS version.
-		 */
-		if (!dmi_get_system_info(DMI_BIOS_VERSION))
-			strlcpy(bios_version, buff, sizeof(bios_version));
-
-		/*
-		 * Check if the two versions match.
-		 */
-		if (strncmp(buff, bios_version, sizeof(bios_version)) != 0)
-			pr_warn("BIOS version mismatch: %s != %s\n",
-				buff, bios_version);
-	}
-
 	i8k_fan_mult = fan_mult;
 	id = dmi_first_match(i8k_dmi_table);
 	if (id && fan_mult == I8K_FAN_MULT && id->driver_data)