I have a Thecus N5550 NAS with an ICH10R AHCI controller. 5 of the AHCI ports are used for "data" drives, and each of these has an activity LED which is driven by one of the ICH GPIOs. (The other AHCI port is used by the internal SATA DOM.) In order to make the LEDs actually blink, I am wrapping libahci's qc_issue function to blink the LED that corresponds to a given command's port (if any): https://github.com/ipilcher/n5550/blob/master/modules/n5550_ahci_leds.c#L177 I "hook in" the wrapper function by ensuring that my module is loaded immediately after libahci (via modprobe configuration) and directly modifying ahci_ops.qc_issue. I do everything I can think of to make sure that no other libahci users are loaded while I'm making the changes. https://github.com/ipilcher/n5550/blob/master/modules/n5550_ahci_leds.c#L207 I also prevent my module from being unloaded when any other libahci users are loaded. The module keeps an additional reference to itself, which is released when the hook is successfully disabled via sysfs. https://github.com/ipilcher/n5550/blob/master/modules/n5550_ahci_leds.c#L79 This definitely works, and it allows me to use pre-packaged kernels on this system (ELRepo kernel-lt on CentOS 6 and hopefully the CentOSPlus kernel on CentOS 7), but it sure does feel ugly and hackish. Short of patching and rebuilding the libahci or ahci modules, is there a better way to do this? (Keeping in mind that I'm not worried about supporting any other hardware configuration.) Thanks! -- ======================================================================== Ian Pilcher arequipeno@xxxxxxxxx -------- "I grew up before Mark Zuckerberg invented friendship" -------- ======================================================================== -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
