Re: [PATCH 01/14] parport: return value of attach and parport_register_driver

From: Sudip Mukherjee
Date: Wed Apr 08 2015 - 07:50:30 EST

On Wed, Apr 08, 2015 at 02:38:32PM +0300, Dan Carpenter wrote:
> 1) We can't apply this patch on its own so this way of breaking up the
> patches doesn't work.
yes, if the first patch is reverted for any reason all the others need
to be reverted also. so then everything in one single patch?
> 2) I was thinking that all the ->attach() calls would have to succeed or
> we would bail. Having some of them succeed and some fail doesn't seem
> like it will simplify the driver code very much. But I can also see
> your point. Hm...
to clarify my point more here: any system might have more than one
parallel port but the module might decide to use just one. so in that
case attach will return 0 for the port that it wishes to use, for others
it will be a error code. So in parport_register_driver if we get error
codes in all the attach calls then we know that attach has definitely
failed, but atleast one 0 means one attach call has succeeded, which
will happen in case of staging/panel, net/plip...

> Minor comment: No need to preserve the error code if there are lots
> which we miss. We may as well hard code an error code. But that's a
> minor thing. Does this actually simplify the driver code? That's the
> more important thing.

i don't think this will simplify the driver code, but atleast now
parport_register_driver() will not report success when we have actually
failed. And as a result module_init will also fail which is supposed to
be the actual behviour.


> regards,
> dan carpenter
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