On Sun, 30 Oct 2016, Jarkko Nikula wrote:
Hi
On Sat, 29 Oct 2016 21:37:04 +0200 Julia Lawall Julia.Lawall@lip6.fr wrote:
Use DEVICE_ATTR_RW for read-write attributes. This simplifies the source code, improves readbility, and reduces the chance of inconsistencies.
...
- DEVICE_ATTR(x, (0644|S_IRUGO|S_IWUSR), x_show, x_store);
- DEVICE_ATTR_RW(x);
I'm not so sure does this improve readability. 644 is pretty obvious but for DEVICE_ATTR_RW() one has to dive into include/linux/device.h and include/linux/sysfs.h to see for what users it grants the write access.
OK, as you like. It does help ensure that the functions that are supposed to be defined are available. There were a couple of occurrences of 0644 with no show or no store function. Among the three declarers, there are currently in total over 800 uses in the kernel, so they are also not so obscure.
julia