The question is two-folded, hence the crossposting. I have a kernel that runs perfectly on my beaglebone black, except for one thing - the kmod for the watchdog is not autoloaded upon boot albeit the device-tree node is present: ubuntu@beaglebone:~$ dmesg | grep wdt ubuntu@beaglebone:~$ ll /dev/watch* ls: cannot access /dev/watch*: No such file or directory ubuntu@beaglebone:~$ ls -la /proc/device-tree/ocp/wdt\@44e35000/ total 0 drwxr-xr-x 2 root root 0 Aug 25 13:43 . drwxr-xr-x 54 root root 0 Aug 25 13:43 .. -r--r--r-- 1 root root 13 Aug 25 13:43 compatible -r--r--r-- 1 root root 4 Aug 25 13:43 interrupts -r--r--r-- 1 root root 4 Aug 25 13:43 name -r--r--r-- 1 root root 8 Aug 25 13:43 reg -r--r--r-- 1 root root 10 Aug 25 13:43 ti,hwmods ubuntu@beaglebone:~$ cat /proc/device-tree/ocp/wdt\@44e35000/compatible ti,omap3-wdt ubuntu@beaglebone:~$ ls -la /sys/bus/platform/devices/ocp/*wdt* total 0 drwxr-xr-x 3 root root 0 Aug 25 13:49 ./ drwxr-xr-x 33 root root 0 Aug 25 13:49 ../ -rw-r--r-- 1 root root 4096 Aug 25 13:49 driver_override -r--r--r-- 1 root root 4096 Aug 25 13:49 modalias lrwxrwxrwx 1 root root 0 Aug 25 13:49 of_node -> ../../../../firmware/devicetree/base/ocp/wdt@44e35000/ drwxr-xr-x 2 root root 0 Aug 25 13:49 power/ lrwxrwxrwx 1 root root 0 Aug 25 13:49 subsystem -> ../../../../bus/platform/ -rw-r--r-- 1 root root 4096 Aug 25 13:49 uevent and if i manually load the module: ubuntu@beaglebone:~$ sudo modprobe omap_wdt ubuntu@beaglebone:~$ dmesg | grep wdt [ 388.104283] omap_wdt: OMAP Watchdog Timer Rev 0x01: initial timeout 60 sec ubuntu@beaglebone:~$ ls -la /dev/watchdog* crw------- 1 root root 10, 130 Aug 25 13:46 /dev/watchdog crw------- 1 root root 251, 0 Aug 25 13:46 /dev/watchdog0 ubuntu@beaglebone:~$ ls -la /sys/bus/platform/devices/ocp/*wdt* total 0 drwxr-xr-x 3 root root 0 Aug 25 13:53 . drwxr-xr-x 33 root root 0 Aug 25 13:49 .. lrwxrwxrwx 1 root root 0 Aug 25 13:53 driver -> ../../../../bus/platform/drivers/omap_wdt -rw-r--r-- 1 root root 4096 Aug 25 13:49 driver_override -r--r--r-- 1 root root 4096 Aug 25 13:49 modalias lrwxrwxrwx 1 root root 0 Aug 25 13:49 of_node -> ../../../../firmware/devicetree/base/ocp/wdt@44e35000 drwxr-xr-x 2 root root 0 Aug 25 13:49 power lrwxrwxrwx 1 root root 0 Aug 25 13:49 subsystem -> ../../../../bus/platform -rw-r--r-- 1 root root 4096 Aug 25 13:49 uevent and then the device works as expected. So here are my questions: 1) My understanding was that, once a device node was present in the device-tree and there was a compatible driver available, it would have been autoloaded, so why it's not happening here? 2) And more importantly, how do i debug these situations? Building a kernel with the driver built-in, and comparing the two dmesgs, didn't show any noticeable difference either. Any idea? -- bye, p. -- 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
