Standard handling of boolean attributes in sysfs.

Hi All,

Just wondering what the feeling would be about having a utility function similar to sysfs_streq to provide a consistent option for all those sysfs attributes out there where

1, on, true -> 1
0, off, false -> 0

Or does such a beast already exist and I'm just being unobservant?

Quoted 7 lines · Jonathan Cameron

Hi All,

Just wondering what the feeling would be about having a utility function similar to sysfs_streq to provide a consistent option for all those sysfs attributes out there where

Quoted 4 lines

1, on, true -> 1
0, off, false -> 0

Or does such a beast already exist and I'm just being unobservant?

We have the one in debugfs that I think people use for sysfs. Have you looked at that?

Quoted 8 lines · Greg KH

Quoted 7 lines · Jonathan Cameron

Hi All,

Just wondering what the feeling would be about having a utility function similar to sysfs_streq to provide a consistent option for all those sysfs attributes out there where

Quoted 8 lines

Quoted 4 lines

1, on, true -> 1
0, off, false -> 0

Or does such a beast already exist and I'm just being unobservant?

We have the one in debugfs that I think people use for sysfs. Have you looked at that?

Thanks for the pointer...

write_file_bool in fs/debugfs/file.c?

What is there is pretty much what is needed, but it's not a general use function like sysfs_streq. Clearly it would make sense to use what is there as a basis of such a function.

To save others looking it up, the relevant bit is:

	switch (buf[0]) {
	case 'y':
	case 'Y':
	case '1':
		*val = 1;
		break;
	case 'n':
	case 'N':
	case '0':
		*val = 0;
		break;
	}

There are a few cut and paste copies of this about (mostly in IIO drivers actually hence why I asking if there is a better way :).

Unless there is demand for it elsewhere I'll just add a utility function to the IIO core to do this and we can revisit the case for a general function when the need turns up elsewhere.

Quoted 43 lines · Jonathan Cameron

Quoted 8 lines · Greg KH

Quoted 7 lines · Jonathan Cameron

Hi All,

Just wondering what the feeling would be about having a utility function similar to sysfs_streq to provide a consistent option for all those sysfs attributes out there where

Quoted 8 lines

Quoted 4 lines

1, on, true -> 1
0, off, false -> 0

Or does such a beast already exist and I'm just being unobservant?

We have the one in debugfs that I think people use for sysfs. Have you looked at that?

Thanks for the pointer...

write_file_bool in fs/debugfs/file.c?

What is there is pretty much what is needed, but it's not a general use function like sysfs_streq. Clearly it would make sense to use what is there as a basis of such a function.

To save others looking it up, the relevant bit is:

	switch (buf[0]) {
	case 'y':
	case 'Y':
	case '1':
		*val = 1;
		break;
	case 'n':
	case 'N':
	case '0':
		*val = 0;
		break;
	}

There are a few cut and paste copies of this about (mostly in IIO drivers actually hence why I asking if there is a better way :).

Quoted 3 lines

Unless there is demand for it elsewhere I'll just add a utility function to the IIO core to do this and we can revisit the case for a general function when the need turns up elsewhere.

The other function that does this, and is what I was thinking of, is param_set_bool(). Care to merge both of these functions together into something "sane" and have everyone use it?