hwmon: (coretemp) Fix TjMax for Atom N450/D410/D510 CPUs

The max junction temperature of Atom N450/D410/D510 CPUs is 100 degrees
Celsius. Since these CPUs are always coupled with Intel NM10 chipset in
one package, the best way to verify whether an Atom CPU is N450/D410/D510
is to check the host bridge device.

Signed-off-by: Yong Wang <[e-mail]>
Acked-by: Huaxu Wan <[e-mail]>
Signed-off-by: Jean Delvare <[e-mail]>

drivers/hwmon/Kconfig

···
 
 config SENSORS_CORETEMP
 	tristate "Intel Core/Core2/Atom temperature sensor"
-	depends on X86 && EXPERIMENTAL
+	depends on X86 && PCI && EXPERIMENTAL
 	help
 	  If you say yes here you get support for the temperature
 	  sensor inside your CPU. Most of the family 6 CPUs

drivers/hwmon/coretemp.c

···
 #include <linux/list.h>
 #include <linux/platform_device.h>
 #include <linux/cpu.h>
+#include <linux/pci.h>
 #include <asm/msr.h>
 #include <asm/processor.h>
 
···
 	int usemsr_ee = 1;
 	int err;
 	u32 eax, edx;
+	struct pci_dev *host_bridge;
 
 	/* Early chips have no MSR for TjMax */
 
···
 		usemsr_ee = 0;
 	}
 
-	/* Atoms seems to have TjMax at 90C */
+	/* Atom CPUs */
 
 	if (c->x86_model == 0x1c) {
 		usemsr_ee = 0;
-		tjmax = 90000;
+
+		host_bridge = pci_get_bus_and_slot(0, PCI_DEVFN(0, 0));
+
+		if (host_bridge && host_bridge->vendor == PCI_VENDOR_ID_INTEL
+		    && (host_bridge->device == 0xa000	/* NM10 based nettop */
+		    || host_bridge->device == 0xa010))	/* NM10 based netbook */
+			tjmax = 100000;
+		else
+			tjmax = 90000;
+
+		pci_dev_put(host_bridge);
 	}
 
 	if ((c->x86_model > 0xe) && (usemsr_ee)) {