Hello, I'm new to kernel programming and have been making a kernelmodule to use motherboards RTC alarm feature. Feature wakes computer from mechanical shutdown and is not part of acpi or any other. Problem is that: It is ok to read register values for alarm, but writing is not. Flags in ioport.h are tested with: flag = pci_resource_flags(&chip, PCI_BASE_ADDRESS_0); printk(KERN_ALERT "\n82471eb: test: flag=%d , 0",flag); and following is set: MEM=on, PREFETCH=on, READONLY=on, UNSET=on, others off. This READONLY seems to be the problem. Module is character driver and device (chip eb82471 from Intel) is: struct pci_dev * chp = ( struct pci_dev * ) pci_find_device(INTEL_VID, CHIP_DID, NULL); included are commands: major = register_chrdev(major, DEVICE_NAME, &fops); pci_enable_device(chp); chip=*chp; pci_read_config_byte(&chip, reg, &ptr); pci_write_config_byte(&chip, reg, ptr); Code is simple but long enough to not to paste in this. Can send. chip->driver is NULL, so there is no other driver for it, but device is still found? Found that devices struct resource has the flags. Is for example pci_register_module command necessary instead of plain char_module registering to enable writes? Do flags have to be changed somehow and where, is it possible? In real life, should this kind of code be integrated to some other device driver if it is supposed to be good implementation? Is it in bios that handles chips on board? Can there be two drivers for the same device? regards, jnl ===== _____________________ Jouni J. Laakso jounijl@yahoo.co.uk phone: +358-41-5165554 Helsinki, Finland , ________________________________________________________________________ Want to chat instantly with your online friends? Get the FREE Yahoo! Messenger http://mail.messenger.yahoo.co.uk -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
