no device creation by udev
vm.rod25 at gmail.com
Fri Jul 1 10:38:54 EDT 2016
On Fri, Jun 24, 2016 at 11:44 AM, <anno79 at mailbox.org> wrote:
> I have written the following lines of code
> to get a char device working.
> ( lines with # indicate that I have tried versions of this code snippet
> without them)
> class_hello = class_create(THIS_MODULE, device_name);
> # class_hello->devnode = &hello_devnode;
> retval = alloc_chrdev_region( &dev_file, 0, 1, device_name );
> cdev_init( &device, &file_ops );
> # device.owner = THIS_MODULE;
> # kobject_set_name(&device.kobj, device_name);
> cdev_add( &device, MKDEV(dev_file, 0), 1 )
> device = device_create( class_hello, NULL, MKDEV(dev_file, 0), NULL,
> device_name );
> # kobj_device->devt = MKDEV(dev_file, 0);
> Make it open / close / read / write works fine - but look at that
> $ ls /sys/class/hello/hello
> power subsystem uevent
> The "dev" entry is missing - and udev does not react.
> Anybody knows what is else needed to make udev react?
Did you register ?
This simple tutorial works fine for me , what kernel version are you ussing ?
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