Re: [PATCH] ar9170: implement frequency calibration for one-stage/openfw

["John W. Linville" <linville@tuxdriver.com>]

On Sat, Sep 19, 2009 at 02:21:36PM +0200, Joerg Albert wrote:
> On 09/19/2009 02:02 AM, Andrew Morton wrote:
> > On Thu, 3 Sep 2009 20:25:31 +0200
> > Christian Lamparter <chunkeey@googlemail.com> wrote:
> > 
> >> This patch ports some code from the vendor driver, which is
> >> supposed to upload the right calibration values for the
> >> chosen frequency.
> >>
> >> In theory, this should give a better range and throughput
> >> for all users with the open, or one-stage firmware.
> >>
> >> ...
> >>
> >> +		for (i = 0; i < 76; i++) {
> >> +			u32 phy_data;
> >> +			u8 tmp;
> >> +
> >> +			if (i < 25) {
> >> +				tmp = ar9170_interpolate_val(i, &pwrs[0][0],
> >> +							     &vpds[0][0]);
> >> +			} else {
> >> +				tmp = ar9170_interpolate_val(i - 12,
> >> +							     &pwrs[1][0],
> >> +							     &vpds[1][0]);
> >> +			}
> >> +
> >> +			phy_data |= tmp << ((i & 3) << 3);
> > 
> > Clearly buggy and the compiler warns.  The value of phy_data is unknown
> > here.
> > 
> > How did this get all the way into mainline?
> 
> Strangely it compiles without any warning for me with the latest linux-wireless:

That is strange -- no warning here (F-11) either...

Christian, care to propose a patch?  Or maybe just something like this?

diff --git a/drivers/net/wireless/ath/ar9170/phy.c b/drivers/net/wireless/ath/ar9170/phy.c
index b3e5cf3..49c10cb 100644
--- a/drivers/net/wireless/ath/ar9170/phy.c
+++ b/drivers/net/wireless/ath/ar9170/phy.c
@@ -1220,7 +1220,7 @@ static int ar9170_set_freq_cal_data(struct ar9170 *ar,
 							     &vpds[1][0]);
 			}
 
-			phy_data |= tmp << ((i & 3) << 3);
+			phy_data = tmp << ((i & 3) << 3);
 			if ((i & 3) == 3) {
 				ar9170_regwrite(0x1c6280 + chain * 0x1000 +
 						(i & ~3), phy_data);

John
-- 
John W. Linville		Someday the world will need a hero, and you
linville@tuxdriver.com			might be all we have.  Be ready.