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

[Oscar Carter <oscar.carter@gmx.com>]

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@oracle.com>
> > Signed-off-by: Oscar Carter <oscar.carter@gmx.com>
> > ---
> >  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 ?

> regards,
> dan carpenter
>
Thanks,
oscar carter