lkml.org 
[lkml]   [2019]   [Apr]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [PATCH V2 1/2] ASoC: fsl_asrc: replace the process_option table with function
Date
Hi

>
>
> On Thu, Apr 11, 2019 at 09:39:06AM +0000, S.j. Wang wrote:
>
> > +/*
> > + * Select the pre-processing and post-processing options
>
> By aligning with other function comments:
> /**
> * Select the pre-processing and post-processing options
>
> > + *
> > + * Fsin: input sample rate
> > + * Fsout: output sample rate
>
> I would suggest to use inrate and outrate to keep naming consistent.
>
> > + * pre_proc: return value for pre-processing option
> > + * post_proc: return value for post-processing option */ static int
> > +fsl_asrc_sel_proc(int Fsin, int Fsout, int *pre_proc, int *post_proc)
> > +{
> > + bool det_out_op2_cond;
> > + bool det_out_op0_cond;
>
> By looking at the comments below. Probably better to rename them
> bool post_proc_cond2, post_proc_cond0;
>
> > + /* Codition for selection of post-processing */
>
> "Codition" -> "Conditions"
>
> > + det_out_op2_cond = (((Fsin * 15 > Fsout * 16) & (Fsout < 56000)) |
> > + ((Fsin > 56000) & (Fsout <
> > + 56000)));
>
> Combining Daniel's comments + indentation alignment:
> det_out_op2_cond = (Fsin * 15 > Fsout * 16 && Fsout < 56000) ||
> (Fsin > 56000 && Fsout < 56000);
>
> > + det_out_op0_cond = (Fsin * 23 < Fsout * 8);
> > +
> > + /*
> > + * unsupported case: Tsout>16.125*Tsin, and Tsout>8.125*Tsin.
>
> Funny thing is that there'd be no point in checking the 16.125, if Tsout is
> bigger than 8.125 times of Tsin, i.e. only one condition:
> Tsout > 8.125 * Tsin
>
> > + * Tsout>16.125*Tsin -> Fsin * 8 > 129 * Fsout
> > + * Tsout>8.125*Tsin -> Fsin * 8 > 65 * Fsout
> > + * Tsout>4.125*Tsin -> Fsin * 8 > 33 * Fsout
> > + * Tsout>1.875*Tsin -> Fsin * 8 > 15 * Fsout
>
> Took me a while to understand what it is saying....
>
> Better to write like this:
> /* Does not support cases: Tsout > 8.125 * Tsin */
> if (Fsin * 8 > 65 * Fsout) {
> pair_err("Does not support %d > 8.125 * %d\n", Fsout, Fsin);
> return -EINVAL;
> }
>
> /* Otherwise, select pre_proc between [0, 2] */
> if (Fsin * 8 > 33 * Fsout)
> > + *pre_proc = 2;
> > + else if (Fsin * 8 > 15 * Fsout) {
> > + if (Fsin > 152000)
> > + *pre_proc = 2;
> > + else
> > + *pre_proc = 1;
> > + } else if (Fsin < 76000)
> > + *pre_proc = 0;
> > + else if (Fsin > 152000)
> > + *pre_proc = 2;
> > + else
> > + *pre_proc = 1;
>
> <== Would look better by moving post_cond calculations here.
>
> > + if (det_out_op2_cond)
> > + *post_proc = 2;
> > + else if (det_out_op0_cond)
> > + *post_proc = 0;
> > + else
> > + *post_proc = 1;
>
> And we could remove this check below:
> > + /* unsupported options */
> > + if (*pre_proc == 4 || *pre_proc == 5)
> > + return -EINVAL;
>
> So basically we are doing:
> 1) Error out unsupported cases
> 2) Select pre_proc
> 3) Calculate conditions for post_proc
> 4) Select post_proc
>
> Thanks

Thanks for reviewing, will send v3.

\
 
 \ /
  Last update: 2019-04-17 11:05    [W:0.062 / U:0.784 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site