Listing 4. Controlling the Power of a PCI Slot
buff = kmalloc (count + 1, GFP_KERNEL); if (!buff)
return -ENOMEM;
memset (buff, 0x00, count + 1);
if (copy_from_user ((void *)buff,
(void *)ubuff, count)) {
retval = -EFAULT;
goto exit;
}
lpower = simple_strtoul (buff, NULL, 10);
power = (u8)(lpower & 0xff);
switch (power) {
case 0:
retval = slot->ops->disable_slot(slot);
break;
case 1:
retval = slot->ops->enable_slot(slot);
break;
default:
err ("Illegal value specified for power\n");
retval = -EFAULT;
}
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