Re: [Outreachy kernel] [PATCH 1/2] staging: rtl8723bs: hal: Remove set but unused variables

["Fabio M. De Francesco" <fmdefrancesco@gmail.com>]

On Thursday, April 29, 2021 9:26:20 AM CEST Fabio Aiuto wrote:
> Hi Fabio,
> 
> On Wed, Apr 28, 2021 at 01:33:45PM +0200, Fabio M. De Francesco wrote:
> > Removed four set but unused variables. Issue detected by gcc.
> > 
> > Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
> > ---
> > 
> >  drivers/staging/rtl8723bs/hal/rtl8723b_hal_init.c | 5 -----
> >  1 file changed, 5 deletions(-)
> > 
> > diff --git a/drivers/staging/rtl8723bs/hal/rtl8723b_hal_init.c
> > b/drivers/staging/rtl8723bs/hal/rtl8723b_hal_init.c index 
082448557b53..96cb4426a0f4
> > 100644
> > --- a/drivers/staging/rtl8723bs/hal/rtl8723b_hal_init.c
> > +++ b/drivers/staging/rtl8723bs/hal/rtl8723b_hal_init.c
> > @@ -3900,14 +3900,11 @@ u8 GetHalDefVar8723B(struct adapter *padapter, 
enum
> > hal_def_variable variable, v> 
> >  			u32 cmd;
> >  			u32 ra_info1, ra_info2;
> >  			u32 rate_mask1, rate_mask2;
> > 
> > -			u8 curr_tx_rate, curr_tx_sgi, hight_rate, 
lowest_rate;
> > 
> >  			cmd = 0x40000100 | mac_id;
> >  			rtw_write32(padapter, 
REG_HMEBOX_DBG_2_8723B, cmd);
> >  			msleep(10);
> >  			ra_info1 = rtw_read32(padapter, 0x2F0);
> > 
> > -			curr_tx_rate = ra_info1&0x7F;
> > -			curr_tx_sgi = (ra_info1>>7)&0x01;
> > 
> >  			cmd = 0x40000400 | mac_id;
> >  			rtw_write32(padapter, 
REG_HMEBOX_DBG_2_8723B, cmd);
> > 
> > @@ -3916,8 +3913,6 @@ u8 GetHalDefVar8723B(struct adapter *padapter, enum
> > hal_def_variable variable, v> 
> >  			ra_info2 = rtw_read32(padapter, 0x2F4);
> >  			rate_mask1 = rtw_read32(padapter, 0x2F8);
> >  			rate_mask2 = rtw_read32(padapter, 0x2FC);
> > 
> > -			hight_rate = ra_info2&0xFF;
> > -			lowest_rate = (ra_info2>>8)  & 0xFF;
> > 
> >  		}
> >  		break;
> 
> rate_mask{1,2} and ra_info{1,2} seems to be unused as well.
> 
> thank you,
> 
> fabio
>
Hello Fabio,

I'm not sure about it: rtw_read32 calls a pointer to a function. I'm don't 
know drivers programming, however that function looks like an implementation 
of a read() system call. So I wouldn't be so sure to remove those calls. 

Could calling a (*read) method have side effects on subsequent read()? I mean: 
could it update some internal data structure? If not I can remove the 
variables you mentioned above and the calls to read32.

I'm looking forward to read your reply.

Thanks,

Fabio