RE: [PATCH v3 2/2] ASoC: Intel: Add period size constraint on strago board

[Lu, Brent]

> 
> I don't get this. If the platform driver already stated 240 and 960 samples why
> would 432 be chosen? Doesn't this mean the constraint is not applied?

Hi Pierre,

Sorry for late reply. I used following constraints in V3 patch so any period which
aligns 1ms would be accepted.

+	/*
+	 * Make sure the period to be multiple of 1ms to align the
+	 * design of firmware. Apply same rule to buffer size to make
+	 * sure alsa could always find a value for period size
+	 * regardless the buffer size given by user space.
+	 */
+	snd_pcm_hw_constraint_step(substream->runtime, 0,
+			   SNDRV_PCM_HW_PARAM_PERIOD_SIZE, 48);
+	snd_pcm_hw_constraint_step(substream->runtime, 0,
+			   SNDRV_PCM_HW_PARAM_BUFFER_SIZE, 48);

Regards,
Brent

> 
> > [   52.011146] sound pcmC1D0p: hw_param
> > [   52.011152] sound pcmC1D0p:   ACCESS 0x1
> > [   52.011155] sound pcmC1D0p:   FORMAT 0x4
> > [   52.011158] sound pcmC1D0p:   SUBFORMAT 0x1
> > [   52.011161] sound pcmC1D0p:   SAMPLE_BITS [16:16]
> > [   52.011164] sound pcmC1D0p:   FRAME_BITS [32:32]
> > [   52.011167] sound pcmC1D0p:   CHANNELS [2:2]
> > [   52.011170] sound pcmC1D0p:   RATE [48000:48000]
> > [   52.011173] sound pcmC1D0p:   PERIOD_TIME [9000:9000]
> > [   52.011176] sound pcmC1D0p:   PERIOD_SIZE [432:432]
> > [   52.011179] sound pcmC1D0p:   PERIOD_BYTES [1728:1728]
> > [   52.011182] sound pcmC1D0p:   PERIODS [474:474]
> > [   52.011185] sound pcmC1D0p:   BUFFER_TIME [4266000:4266000]
> > [   52.011188] sound pcmC1D0p:   BUFFER_SIZE [204768:204768]
> > [   52.011191] sound pcmC1D0p:   BUFFER_BYTES [819072:819072]
> > [   52.011194] sound pcmC1D0p:   TICK_TIME [0:0]
> >
> > Regards,
> > Brent
> >
> >>
> >>
> >> Takashi
> >
> >