Re: [PATCH 3/13] drivers/media/tuners/qt1010.c: use macros fori2c_msg initialization

From: Julia Lawall
Date: Tue Oct 09 2012 - 08:51:26 EST


On Tue, 9 Oct 2012, Jean Delvare wrote:

> Hi Julia,
>
> On Mon, 8 Oct 2012 07:24:11 +0200 (CEST), Julia Lawall wrote:
> > > Sorry, I mean either:
> > >
> > > I2C_MSG_WRITE(priv->cfg->i2c_address, &reg, sizeof(reg)),
> > > I2C_MSG_READ(priv->cfg->i2c_address, val, sizeof(*val)),
> >
> > Of course. Sorry for not having seen that. I can do that.
>
> Eek, no, you can't, not in the general case at least. sizeof(*val) will
> return the size of the _first_ element of the destination buffer, which
> has nothing to do with the length of that buffer (which in turn might
> be rightfully longer than the read length for this specific message.)

I was actually only going to do it when the size was 1 and the type was
u8 *. But your other email suggests that converting to sizeof is just not
a good idea at all. So I will drop that part of the rule.

julia
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