From: Carsten Emde <C.Emde@osadl.org>

Date: Mon, 24 May 2010 21:33:39 +0000 (-0700)

Subject: drivers/hwmon/coretemp.c: detect the thermal sensors by CPUID

X-Git-Tag: v2.6.35-rc1~297

X-Git-Url: http://git.kernel.org/?p=linux%2Fkernel%2Fgit%2Ftorvalds%2Flinux-2.6.git;a=commitdiff_plain;h=5db47b009d17d69a2f8d84357e7b24c3e3c2edec

drivers/hwmon/coretemp.c: detect the thermal sensors by CPUID

The thermal sensors of Intel(R) CPUs can be detected by CPUID instruction,

indicated by CPUID.06H.EAX[0].

Signed-off-by: Huaxu Wan <huaxu.wan@linux.intel.com>

Signed-off-by: Carsten Emde <C.Emde@osadl.org>

Reviewed-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>

Cc: Jean Delvare <khali@linux-fr.org>

Cc: Henrique de Moraes Holschuh <hmh@hmh.eng.br>

Cc: Yong Wang <yong.y.wang@linux.intel.com>

Cc: Rudolf Marek <r.marek@assembler.cz>

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

---

diff --git a/drivers/hwmon/coretemp.c b/drivers/hwmon/coretemp.c

index e9b7fbc..9fae7cb 100644

--- a/drivers/hwmon/coretemp.c

+++ b/drivers/hwmon/coretemp.c

@@ -451,28 +451,20 @@ static int __init coretemp_init(void)

 	for_each_online_cpu(i) {

 		struct cpuinfo_x86 *c = &cpu_data(i);

+		/*

+		 * CPUID.06H.EAX[0] indicates whether the CPU has thermal

+		 * sensors. We check this bit only, all the early CPUs

+		 * without thermal sensors will be filtered out.

+		 */

+		if (c->cpuid_level >= 6 && (cpuid_eax(0x06) & 0x01)) {

+			err = coretemp_device_add(i);

+			if (err)

+				goto exit_devices_unreg;

-		/* check if family 6, models 0xe (Pentium M DC),

-		  0xf (Core 2 DC 65nm), 0x16 (Core 2 SC 65nm),

-		  0x17 (Penryn 45nm), 0x1a (Nehalem), 0x1c (Atom),

-		  0x1e (Lynnfield) */

-		if ((c->cpuid_level < 0) || (c->x86 != 0x6) ||

-		    !((c->x86_model == 0xe) || (c->x86_model == 0xf) ||

-			(c->x86_model == 0x16) || (c->x86_model == 0x17) ||

-			(c->x86_model == 0x1a) || (c->x86_model == 0x1c) ||

-			(c->x86_model == 0x1e))) {

-

-			/* supported CPU not found, but report the unknown

-			   family 6 CPU */

-			if ((c->x86 == 0x6) && (c->x86_model > 0xf))

-				printk(KERN_WARNING DRVNAME ": Unknown CPU "

-					"model 0x%x\n", c->x86_model);

-			continue;

+		} else {

+			printk(KERN_INFO DRVNAME ": CPU (model=0x%x)"

+				" has no thermal sensor.\n", c->x86_model);

 		}

-

-		err = coretemp_device_add(i);

-		if (err)

-			goto exit_devices_unreg;

 	}

 	if (list_empty(&pdev_list)) {

 		err = -ENODEV;