[alsa-devel] [PATCH] azt3328: repair breakage (Re: [PATCH 1/1] SOUND: azt3328, fix broken AZF_FMT_XLATE macro)

[Takashi Iwai]

At Tue, 25 Jan 2011 06:46:31 +0100,
Andreas Mohr wrote:
> 
> Cleanly revert to non-macro implementation of
> snd_azf3328_codec_setfmt(), to fix last-minute functionality breakage
> induced by following checkpatch.pl recommendations without giving them
> their due full share of thought ("revolting computer, ensuing PEBKAC").
> 
> I would like to thank Jiri Slaby for his very timely (in -rc1 even)
> and unexpected (uncommon hardware) "recognition of the dangerous situation"
> due to his very commendable static parser use. :)
> 
> Reported-by: Jiri Slaby <jslaby at suse.cz>
> Signed-off-by: Andreas Mohr <andi at lisas.de>

Applied now.  Thanks.


Takashi

> ---
> On Sat, Jan 22, 2011 at 05:26:39PM +0100, Takashi Iwai wrote:
> > At Sat, 22 Jan 2011 14:56:10 +0100,
> > Jiri Slaby wrote:
> > > I vote for removing that crap completely because it makes the code
> > > weird anyway -- you have to specify manually both of freq and bits
> > > which is I would expect to be avoided exactly by such a macro.
> > 
> > I agree.  Andreas, please either revert back to the plain code,
> > or use a simple look-up table if you don't want switch/case.
> 
> And indeed, the currently committed state IS broken since listening to audio
> is strangely devoid of positive effects. :)
> Sucks to be taking a larger tried and tested patch series into the holidays
> and then making minor "improvements" to it before submission.
> 
> 
> I decided that an additional lookup table isn't really worth it,
> thus reverting is probably best.
> 
> 
> The checkpatch.pl false positive (which triggered the horrid mistake of
> additionally enclosing this per-case macro within do-while(0)) was:
> 
> ERROR: Macros with multiple statements should be enclosed in a do - while loop
> #20: FILE: azt3328.c:982:
> +#define AZF_FMT_XLATE(in_freq, out_bits) \
> +               case AZF_FREQ_ ## in_freq: \
> +                       freq = SOUNDFORMAT_FREQ_ ## out_bits; \
> +                       break;
> 
> 
> It is also quite interesting to note that this rather uncommon language syntax
> (do...while(0) within switch scope) compiled cleanly without issue
> (no warnings).
> 
> 
> Please note that this clean revert (exclusively created from existing
> development steps) was compile-tested only and not runtime-tested on -rc2.
> This is due to existing suspected modvers issues on -rc2 (it did work fine
> in many previous versions, now I'm getting unresolved symbols issues
> with my -dirty, extra/ modules, perhaps due to having switched to/enabled
> CONFIG_KERNEL_LZO, CONFIG_DEBUG_SET_MODULE_RONX)
> which I was unable to rectify sufficiently easily so far in my limited time.
> 
> The clean revert will be followed up by
> corresponding comments and some cleanup within that function in the mid-future.
> 
> Thanks,
> 
> Andreas Mohr
> 
> diff --git a/sound/pci/azt3328.c b/sound/pci/azt3328.c
> index 6117595..573594b 100644
> --- a/sound/pci/azt3328.c
> +++ b/sound/pci/azt3328.c
> @@ -979,31 +979,25 @@ snd_azf3328_codec_setfmt(struct snd_azf3328_codec_data *codec,
>  
>  	snd_azf3328_dbgcallenter();
>  	switch (bitrate) {
> -#define AZF_FMT_XLATE(in_freq, out_bits) \
> -	do { \
> -		case AZF_FREQ_ ## in_freq: \
> -			freq = SOUNDFORMAT_FREQ_ ## out_bits; \
> -			break; \
> -	} while (0);
> -	AZF_FMT_XLATE(4000, SUSPECTED_4000)
> -	AZF_FMT_XLATE(4800, SUSPECTED_4800)
> -	/* the AZF3328 names it "5510" for some strange reason: */
> -	AZF_FMT_XLATE(5512, 5510)
> -	AZF_FMT_XLATE(6620, 6620)
> -	AZF_FMT_XLATE(8000, 8000)
> -	AZF_FMT_XLATE(9600, 9600)
> -	AZF_FMT_XLATE(11025, 11025)
> -	AZF_FMT_XLATE(13240, SUSPECTED_13240)
> -	AZF_FMT_XLATE(16000, 16000)
> -	AZF_FMT_XLATE(22050, 22050)
> -	AZF_FMT_XLATE(32000, 32000)
> +	case AZF_FREQ_4000:  freq = SOUNDFORMAT_FREQ_SUSPECTED_4000; break;
> +	case AZF_FREQ_4800:  freq = SOUNDFORMAT_FREQ_SUSPECTED_4800; break;
> +	case AZF_FREQ_5512:
> +		/* the AZF3328 names it "5510" for some strange reason */
> +			     freq = SOUNDFORMAT_FREQ_5510; break;
> +	case AZF_FREQ_6620:  freq = SOUNDFORMAT_FREQ_6620; break;
> +	case AZF_FREQ_8000:  freq = SOUNDFORMAT_FREQ_8000; break;
> +	case AZF_FREQ_9600:  freq = SOUNDFORMAT_FREQ_9600; break;
> +	case AZF_FREQ_11025: freq = SOUNDFORMAT_FREQ_11025; break;
> +	case AZF_FREQ_13240: freq = SOUNDFORMAT_FREQ_SUSPECTED_13240; break;
> +	case AZF_FREQ_16000: freq = SOUNDFORMAT_FREQ_16000; break;
> +	case AZF_FREQ_22050: freq = SOUNDFORMAT_FREQ_22050; break;
> +	case AZF_FREQ_32000: freq = SOUNDFORMAT_FREQ_32000; break;
>  	default:
>  		snd_printk(KERN_WARNING "unknown bitrate %d, assuming 44.1kHz!\n", bitrate);
>  		/* fall-through */
> -	AZF_FMT_XLATE(44100, 44100)
> -	AZF_FMT_XLATE(48000, 48000)
> -	AZF_FMT_XLATE(66200, SUSPECTED_66200)
> -#undef AZF_FMT_XLATE
> +	case AZF_FREQ_44100: freq = SOUNDFORMAT_FREQ_44100; break;
> +	case AZF_FREQ_48000: freq = SOUNDFORMAT_FREQ_48000; break;
> +	case AZF_FREQ_66200: freq = SOUNDFORMAT_FREQ_SUSPECTED_66200; break;
>  	}
>  	/* val = 0xff07; 3m27.993s (65301Hz; -> 64000Hz???) hmm, 66120, 65967, 66123 */
>  	/* val = 0xff09; 17m15.098s (13123,478Hz; -> 12000Hz???) hmm, 13237.2Hz? */
>