Hi, On Tue, Oct 20, 2009 at 7:25 PM, Rick Brown <rick.brown.3@xxxxxxxxx> wrote: > Hi, > > I'm trying to write a simple driver using some registers of my hardware. > > Is a call to request_mem_region() advisory ("recommended") or > compulsory before I ioremap the memory? I think it is "compulsory" recommened. > > In other words, if I don't use request_mem_region() before I start > using the memory; is my driver BOUND to fail, or it MAY fail? You need to call request_mem_region in order to verify that no other device is using the same address resource. So your driver might FAIL if the address is already reserved for another device. thanks, Daniel. -- To unsubscribe from this list: send the line "unsubscribe linux-newbie" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.linux-learn.org/faqs