Fwd: [PATCH 7/9] ASoC: Blackfin: I2S CPU DAI driver

["John Kacur" <jkacur@gmail.com>]

On Thu, Sep 4, 2008 at 4:43 PM, Mark Brown
<broonie@opensource.wolfsonmicro.com> wrote:
>
> On Thu, Sep 04, 2008 at 04:22:06PM +0800, Bryan Wu wrote:
> > From: Cliff Cai <cliff.cai@analog.com>
> >
> > Signed-off-by: Cliff Cai <cliff.cai@analog.com>
> > Signed-off-by: Bryan Wu <cooloney@kernel.org>
>
> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
>
> Please fix the minor issues below as incremental patches for ease of
> review.
>
> > +     switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
> > +     case SND_SOC_DAIFMT_I2S:
> > +             break;
> > +     case SND_SOC_DAIFMT_LEFT_J:
> > +             ret = -EINVAL;
> > +             break;
> > +     }
>
> The SND_SOC_DAFIMT_LEFT_J: ought to be default: instead - there's more
> DAI formats than just that.
>
> > +     if (!bf5xx_i2s.master) {
> > +     /*
> > +      * TX and RX are not independent,they are enabled at the same time,
> > +      * even if only one side is running.So,we need to configure both of
> > +      * them in advance.
> > +      *
> > +      * CPU DAI format:I2S, slave mode.
> > +      */

+       switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
+       case SND_SOC_DAIFMT_CBS_CFS:
+               ret = -EINVAL;
+               break;
+       case SND_SOC_DAIFMT_CBM_CFS:
+               ret = -EINVAL;
+               break;
+       case SND_SOC_DAIFMT_CBM_CFM:
+               break;
+       case SND_SOC_DAIFMT_CBS_CFM:
+               ret = -EINVAL;
+               break;
+       default:
+               break;
+       }

My eyes fell upon this switch statement, probably I have similar
criticisms as to what has already been said, but:
1. Surely the default case is also an -EINVAL
2. Why not let all the EINVALS fall through, it will shorten up the
code, and IMO make it more readable, something like this?
+       switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
+       case SND_SOC_DAIFMT_CBM_CFM: /* Passing Case */
+               break;
+       case SND_SOC_DAIFMT_CBS_CFS: /* Failing Cases */
+       case SND_SOC_DAIFMT_CBM_CFS:
+       case SND_SOC_DAIFMT_CBS_CFM:
+               ret = -EINVAL;
+               break;
+       default:
+               printk(KERN_INFO "Unknown SND_SOC_DAIFMT kind\n");
+               ret = -EINVAL;
+               break;
+       }