On Thu, Jan 20, 2005 at 01:06:55PM -0600, Kumar Gala wrote: > Russell, > > I think this all makes sense to me. I'm just wondering why we would > have a platform device register in a system for 'legacy ISA' when we > know the system doesnt have any ports that will fit the category. > > As you show in example #2 you have > > .../devices/platform/serial82500 > .../devices/platform/serial8250 > > why have the 'serial8250' if you know your system doesnt have any ports > that will exist there?
In this case, it is a placeholder, and needs to be there if you're using power management. For instance, you may use setserial on /dev/ttyS2 to reconfigure it to an address where you know a serial port is. Without the "serial8250" device, it isn't linked into the device model, and therefore doesn't receive any power management notifications. Once the SERIAL_PORT_DFNS are gone, and we have a more modern interface than setserial for setting up random ports, this "serial8250" device will vanish. While we're here, you've reminded me about an annoying point about platform device naming... Greg - the name is constructed from "name" + "id num" thusly: serial8250 serial82500 serial82501 serial82502 When "name" ends in a number, it gets rather confusing. Can we have an optional delimiter in there when we append the ID number, maybe something like a '.' or ':' ? -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: 2.6 PCMCIA - http://pcmcia.arm.linux.org.uk/ 2.6 Serial core - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/