Re: [PATCH] staging: vt6656: Use defines in vnt_mac_reg_bits_* functions

[Malcolm Priestley]

On 02/04/2020 10:19, Quentin Deslandes wrote:
> On 04/01/20 18:55:38, Oscar Carter wrote:
> > On Tue, Mar 31, 2020 at 01:29:06PM +0300, Dan Carpenter wrote:
> > > On Sat, Mar 28, 2020 at 10:54:33AM +0100, Oscar Carter wrote:
> > > > Define the necessary bits in the CHANNEL, PAPEDELAY and GPIOCTL0
> > > > registers to can use them in the calls to vnt_mac_reg_bits_on and
> > > > vnt_mac_reg_bits_off functions. In this way, avoid the use of BIT()
> > > > macros and clarify the code.
> > > >
> > > > Fixes: 3017e587e368 ("staging: vt6656: Use BIT() macro in vnt_mac_reg_bits_* functions")
> > > > Suggested-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> > > > Signed-off-by: Oscar Carter <oscar.carter@xxxxxxx>
> > > > ---
> > > >   drivers/staging/vt6656/baseband.c |  6 ++++--
> > > >   drivers/staging/vt6656/card.c     |  3 +--
> > > >   drivers/staging/vt6656/mac.h      | 12 ++++++++++++
> > > >   drivers/staging/vt6656/main_usb.c |  2 +-
> > > >   4 files changed, 18 insertions(+), 5 deletions(-)
> > > >
> > > > diff --git a/drivers/staging/vt6656/baseband.c b/drivers/staging/vt6656/baseband.c
> > > > index a19a563d8bcc..dd3c3bf5e8b5 100644
> > > > --- a/drivers/staging/vt6656/baseband.c
> > > > +++ b/drivers/staging/vt6656/baseband.c
> > > > @@ -442,7 +442,8 @@ int vnt_vt3184_init(struct vnt_private *priv)
> > > >   		if (ret)
> > > >   			goto end;
> > > >
> > > > -		ret = vnt_mac_reg_bits_on(priv, MAC_REG_PAPEDELAY, BIT(0));
> > > > +		ret = vnt_mac_reg_bits_on(priv, MAC_REG_PAPEDELAY,
> > > > +					  PAPEDELAY_B0);
> > >
> > > This doesn't clarify anything.  It makes it less clear because someone
> > > would assume B0 means something but it's just hiding a magic number
> > > behind a meaningless define.  B0 means BIT(0) which means nothing.  So
> > > now we have to jump through two hoops to find out that we don't know
> > > anything.
> > I created this names due to the lack of information about the hardware. I
> > searched but I did not find anything.
> >
> > > Just leave it as-is.  Same for the rest.
> > Ok.
> >
> > > There problem is a hardware spec which explains what this stuff is.
> > It's possible to find a datasheet of this hardware to make this modification
> > accordingly to the correct bit names of registers ?
>
> I haven't found any so far, if your researches are luckier than mine, I
> would be interested too. Even getting your hands on the actual device is
> complicated.

All I can tell you is it related to command above it MAC_REG_ITRTMSET 
without it the device will not associate with access point is probably 
TX timing/power rated.

Other bits in MAC_REG_PAPEDELAY are related to LED function and defined 
in LEDSTS_* in mac.h.

I think it is some kind of enable so something like ITRTMSET_ENABLE 
would do.

Regards

Malcolm