From 99dbd4efd6d5ecc37d7e8f28b20d9be8c83055c7 Mon Sep 17 00:00:00 2001 From: Ben Warren Date: Mon, 5 Oct 2009 00:02:51 -0700 Subject: 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: Ben Warren --- doc/README.drivers.eth | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) (limited to 'doc') diff --git a/doc/README.drivers.eth b/doc/README.drivers.eth index 7f2190998..e06d3ad44 100644 --- a/doc/README.drivers.eth +++ b/doc/README.drivers.eth @@ -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 -- cgit v1.2.3