Re: [PATCH V14 1/2] scsi: ufs: set the device reference clock setting

[Sayali Lokhande]

On 9/24/2018 1:28 PM, Avri Altman wrote:
> > +static struct ufs_ref_clk ufs_ref_clk_freqs[] = {
> > +       {19200000, REF_CLK_FREQ_19_2_MHZ},
> > +       {26000000, REF_CLK_FREQ_26_MHZ},
> > +       {38400000, REF_CLK_FREQ_38_4_MHZ},
> > +       {52000000, REF_CLK_FREQ_52_MHZ},
> > +       {0, REF_CLK_FREQ_INVAL},
> > +};
> > +
> > +static inline enum ufs_ref_clk_freq
> > +ufs_get_bref_clk_from_hz(u32 freq)
> > +{
> > +       int i = 0;
> > +
> > +       while (ufs_ref_clk_freqs[i].freq_hz != freq) {
> > +               if (!ufs_ref_clk_freqs[i].freq_hz)
> > +                       return REF_CLK_FREQ_INVAL;
> Is the if clause really needed?
> you will return REF_CLK_FREQ_INVAL anyway
Yes. the if condition makes sure to return REF_CLK_FREQ_INVAL if freq is 
not what we expect.
> > +               i++;
> You might overrun here if freq is not what you've expected
Above if condition "if (!ufs_ref_clk_freqs[i].freq_hz)" prevents such 
overrun
as we will reach end of ufs_ref_clk_freqs[] (i.e upto 0, 
REF_CLK_FREQ_INVAL) when there is no match and thus we will return 
REF_CLK_FREQ_INVAL.
> > +       }
> > +
> > +       return ufs_ref_clk_freqs[i].val;
> > +}