Commit 99dbd4ef authored by Ben Warren's avatar Ben Warren

Add information about return values of xxx_eth_register() in documentation

As discussed on mailing list, <0 indicates failure, >=0 indicates number
of interfaces found.

Also added blurb about private data
Signed-off-by: 's avatarBen Warren <biggerbadderben@gmail.com>
parent 1f1e774e
......@@ -25,9 +25,9 @@ system handling, but ultimately they will call the driver-specific register
function which in turn takes care of initializing that particular instance.
Keep in mind that you should code the driver to avoid storing state in global
data as someone might want to hook up two of the same devices to one board. If
the state is maintained as global data, it makes using both of those devices
impossible.
data as someone might want to hook up two of the same devices to one board.
Any such information that is specific to an interface should be stored in a
private, driver-defined data structure and pointed to by eth->priv (see below).
So the call graph at this stage would look something like:
board_init()
......@@ -77,15 +77,20 @@ int ape_register(bd_t *bis, int iobase)
miiphy_register(dev->name, ape_mii_read, ape_mii_write);
#endif
return 0;
return 1;
}
The exact arguments needed to initialize your device are up to you. If you
need to pass more/less arguments, that's fine. You should also add the
prototype for your new register function to include/netdev.h. You might notice
that many drivers seem to use xxx_initialize() rather than xxx_register().
This is the old naming convention and should be avoided as it causes confusion
with the driver-specific init function.
prototype for your new register function to include/netdev.h.
The return value for this function should be as follows:
< 0 - failure (hardware failure, not probe failure)
>=0 - number of interfaces detected
You might notice that many drivers seem to use xxx_initialize() rather than
xxx_register(). This is the old naming convention and should be avoided as it
causes confusion with the driver-specific init function.
Other than locating the MAC address in dedicated hardware storage, you should
not touch the hardware in anyway. That step is handled in the driver-specific
......
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