On Mon, Apr 20, 2015 at 09:56:48AM -0600, Jason Gunthorpe wrote: > On Mon, Apr 20, 2015 at 04:54:32PM +0200, Greg Kroah-Hartman wrote: > > On Sun, Apr 19, 2015 at 11:08:00PM -0600, Jason Gunthorpe wrote: > > > I still suspect the expected way to write a new mid layer is to create > > > your own struct device and not rely on misc_device, > > > > Yes, that is the way. You can not use misc_device for anything other > > than creating the char node that your driver can use through the fileops > > you pass to it. > > > > Do not use a misc_device to create sysfs files for, or anything else, it > > will be wrong and racy, as you have pointed out. > > Thanks! > > Can you quickly comment on when a misc device should be used compared to > alloc_chrdev_region & cdev_add ? If you need more than one character device node, don't use a misc device. If you only need one, and nothing "special" or "fancy", and don't want to put sysfs attribute files on your device, then use a misc device. thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
