Re: [PATCH] staging: vt6656: Refactor the vnt_ofdm_min_rate function

[Malcolm Priestley]

Hi all

On 19/04/2020 18:55, Stefano Brivio wrote:
> Hi Oscar,
>
> On Sat, 18 Apr 2020 15:45:53 +0200
> Oscar Carter <oscar.carter@xxxxxxx> wrote:
>
> > Replace the for loop by a ternary operator whose condition is an AND
> > bitmask against the priv->basic_rates variable.
> >
> > The purpose of the for loop was to check if any of bits from RATE_54M to
> > RATE_6M was set, but it's not necessary to check every individual bit.
> > The same result can be achieved using only one single mask which
> > comprises all the commented bits.
<snip>

> > -int vnt_ofdm_min_rate(struct vnt_private *priv)
> > +bool vnt_ofdm_min_rate(struct vnt_private *priv)
> >   {
> > -	int ii;
> > -
> > -	for (ii = RATE_54M; ii >= RATE_6M; ii--) {
> > -		if ((priv->basic_rates) & ((u16)BIT(ii)))
> > -			return true;
> > -	}
> > -
> > -	return false;
> > +	return priv->basic_rates & GENMASK(RATE_54M, RATE_6M) ? true : false;
>
> priv->basic_rates & GENMASK(RATE_54M, RATE_6M) is already true if
> non-zero and false otherwise. Note that I haven't checked if the
> rest is correct.
Yes only 1 or more needs to be true and it is false when none present.

I have run-time checked the patch and it does function as before.

Regards

Malcolm.