/* Tries to activate the SpeedStep status and control registers. Returns -EINVAL on an unsupported chipset, and zero on success.  */
static int speedstep_activate(void)
/* Tries to activate the SpeedStep status and control registers. Returns -EINVAL on an unsupported chipset, and zero on success.  */
static int speedstep_activate(void)
{
	u16 value = 0;
	if (!speedstep_chipset_dev)
		return -EINVAL;
	pci_read_config_word(speedstep_chipset_dev, 0x00A0, &value);
	if (!(value & 0x08)) {
		value |= 0x08;
		dprintk("activating SpeedStep (TM) registers\n");
		pci_write_config_word(speedstep_chipset_dev, 0x00A0, value);
	}
	return 0;
}