Re: [PATCH] media: allegro-dvt: Use __packed sentence

[Michael Tretter]

On Fri, 29 Jan 2021 23:54:41 +0000, David Laight wrote:
> From: Emmanuel Arias
> > Sent: 29 January 2021 20:02
> > 
> > Fix coding style using __packed sentece instead of
> > __attribute__((__packed__)).
> > 
> > Signed-off-by: Emmanuel Arias <eamanu@xxxxxxxxxxx>
> > ---
> >  drivers/staging/media/allegro-dvt/allegro-core.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/staging/media/allegro-dvt/allegro-core.c b/drivers/staging/media/allegro-
> > dvt/allegro-core.c
> > index 9f718f43282b..cee624dac61a 100644
> > --- a/drivers/staging/media/allegro-dvt/allegro-core.c
> > +++ b/drivers/staging/media/allegro-dvt/allegro-core.c
> > @@ -670,7 +670,7 @@ static ssize_t allegro_mbox_read(struct allegro_mbox *mbox,
> >  	struct {
> >  		u16 length;
> >  		u16 type;
> > -	} __attribute__ ((__packed__)) *header;
> > +	} __packed *header;
> >  	struct regmap *sram = mbox->dev->sram;
> 
> Does this actually need to be packed?
> The only reason would be if the structure could exist on a 2n+1
> boundary.

Not sure, what you mean by this.

> But that is only likely if part of some binary sequence.
> In which case I'd expect it to be marked __be or __le.

It is part of a binary sequence. It is the header of messages in a mailbox
that is used to exchange data with a co-processor (video encoder). In fact, it
should be marked as __le.

Michael