July 2011 - Alsa-devel - mailman.alsa-project.org

Re: [alsa-devel] [PATCH 2/5] ASoC: atmel-ssc: add phybase in device structure
by Mark Brown 01 Jul '11

01 Jul '11

On Wed, Jun 29, 2011 at 08:00:16PM +0200, Nicolas Ferre wrote: > struct ssc_device { > struct list_head list; > + resource_size_t phybase; The type here looks rather wrong?

2 1

[alsa-devel] alsa-lib rate plugins - float samples
by Pavel Hofman 01 Jul '11

01 Jul '11

Hi, This is probably a question for Jaroslav Kysela. The better-quality rate plugins offer float resolution, but currently we are deliberately loosing information by down-converting to s16 in plugin_rate API (convert_s16). In rate_samplerate.c, the samples are up-converted to float before calling the libsamplerate API. Speex offers float API too, while we are using the int16 one. There are two ways to handle this: A. Implementing the generic "convert" API function for these plugins, handling the sample - float conversion in each plugin individually. B. Extending the pcm_rate API (pcm_rate.h) with a new optional function convert_float. Since the conversion from general sample format to float is not trivial (using the plugin_ops.h operations), I would be inclined to suggest the extension (well I have it hacked already :-) ). On the other hand, the conversion routine can be located in some common code shared by all the plugins involved and we could keep the existing API, using the generic convert function. Thanks a lot for suggestions. Best regards, Pavel.

2 5

Re: [alsa-devel] [PATCH 1/5] ASoC: wm8731: rework power management
by Mark Brown 01 Jul '11

01 Jul '11

On Wed, Jun 29, 2011 at 08:00:15PM +0200, Nicolas Ferre wrote: Don't mix multiple changes into a single patch! There's no perceptible code overlap between these so I don't understand why you've merged them, it just makes review harder and the changelog less descriptive. > - preserve crystal oscillator across suspend/resume sequence: > enabled by default, it should be kept enabled on resume. This isn't what your code does... > - if codec is in active state: set the active bit at resume time. Your changelog doesn't explain what the actual problem is here... I can see it by studying the diff but the changelog makes me think the change is bad as the subsystem shuts everything down before it enters CODEC suspend... > snd_soc_write(codec, WM8731_ACTIVE, 0x0); > - snd_soc_write(codec, WM8731_PWR, 0xffff); > + /* standby: keep crystal oscillator enabled */ > + snd_soc_write(codec, WM8731_PWR, 0x00df); This doesn't keep the crystal oscillator enabled, this forces it on in suspend (and without looking at the datasheet it also changes way more than the one register bit I'd expect to be changed). If the system isn't using the oscillator then that's not good. I'd expect to see a change to using snd_soc_update_bits() based on your description, or more likely something more involved. > @@ -533,6 +534,8 @@ static int wm8731_suspend(struct snd_soc_codec *codec, pm_message_t state) > static int wm8731_resume(struct snd_soc_codec *codec) > { > wm8731_set_bias_level(codec, SND_SOC_BIAS_STANDBY); > + if (codec->active) > + snd_soc_write(codec, WM8731_ACTIVE, 0x0001); This should be handled as part of the bias level managemnent and cache sync, if the disable happens in bias level management so should the restore.

2 4