On 01/18/2017 09:26 AM, Matt Ranostay wrote: > We can get audio errors if hitting deeper idle states on omaps: > > [alsa.c:230] error: Fatal problem with alsa output, error -5. > [audio.c:614] error: Error in writing audio (Input/output error?)! > > This seems to happen with off mode idle enabled as power for the > whole SoC may get cut off between filling the McBSP fifo using DMA. > While active DMA blocks deeper idle states in hardware, McBSP > activity does not seem to do so. > > Basing the QoS latency calculation on the FIFO size, threshold, > sample rate, and channels. > > Based on the original patch by Tony Lindgren > Link: https://patchwork.kernel.org/patch/9305867/ Acked-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx> > > Cc: Tony Lindgren <tony@xxxxxxxxxxx> > Cc: Peter Ujfalusi <peter.ujfalusi@xxxxxx> > Signed-off-by: Matt Ranostay <matt@ranostay.consulting> > --- > Changes from v1: > * add calculations for latency per number of FIFO locations > > Changes from v2: > * add missing mcbsp.h header change > > Changes from v3: > * base the latency calculations on threshold, buffer size, sample > rate, and channels > > Changes from v4: > * using Peter Ujfalusi's suggestions for restoring a higher latency on > audio stream completion, or if not applicable remove the QoS request > > Changes from v5: > * clean up latency checking logic > * move logic to .prepare and .shutdown to avoid functions that can sleep > > Changes from v6: > * move QoS removal to asoc_mcbsp_remove from omap_mcbsp_cleanup > * also remove header include that is unneeded > > Changes from v7: > * fix issue reported by Tony Lindgreen that a player application could close the > card after hw_params, and cause an invalid pm_qos_remove_request() > > sound/soc/omap/mcbsp.h | 3 +++ > sound/soc/omap/omap-mcbsp.c | 48 ++++++++++++++++++++++++++++++++++++++++++++- > 2 files changed, 50 insertions(+), 1 deletion(-) > > diff --git a/sound/soc/omap/mcbsp.h b/sound/soc/omap/mcbsp.h > index 61e93b1c185d..46ae1269a698 100644 > --- a/sound/soc/omap/mcbsp.h > +++ b/sound/soc/omap/mcbsp.h > @@ -323,8 +323,11 @@ struct omap_mcbsp { > > unsigned int fmt; > unsigned int in_freq; > + unsigned int latency[2]; > int clk_div; > int wlen; > + > + struct pm_qos_request pm_qos_req; > }; > > void omap_mcbsp_config(struct omap_mcbsp *mcbsp, > diff --git a/sound/soc/omap/omap-mcbsp.c b/sound/soc/omap/omap-mcbsp.c > index d018e966e533..6b40bdbef336 100644 > --- a/sound/soc/omap/omap-mcbsp.c > +++ b/sound/soc/omap/omap-mcbsp.c > @@ -157,6 +157,17 @@ static void omap_mcbsp_dai_shutdown(struct snd_pcm_substream *substream, > struct snd_soc_dai *cpu_dai) > { > struct omap_mcbsp *mcbsp = snd_soc_dai_get_drvdata(cpu_dai); > + int tx = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK); > + int stream1 = tx ? SNDRV_PCM_STREAM_PLAYBACK : SNDRV_PCM_STREAM_CAPTURE; > + int stream2 = tx ? SNDRV_PCM_STREAM_CAPTURE : SNDRV_PCM_STREAM_PLAYBACK; > + > + if (mcbsp->latency[stream2]) > + pm_qos_update_request(&mcbsp->pm_qos_req, > + mcbsp->latency[stream2]); > + else if (mcbsp->latency[stream1]) > + pm_qos_remove_request(&mcbsp->pm_qos_req); > + > + mcbsp->latency[stream1] = 0; > > if (!cpu_dai->active) { > omap_mcbsp_free(mcbsp); > @@ -164,6 +175,28 @@ static void omap_mcbsp_dai_shutdown(struct snd_pcm_substream *substream, > } > } > > +static int omap_mcbsp_dai_prepare(struct snd_pcm_substream *substream, > + struct snd_soc_dai *cpu_dai) > +{ > + struct omap_mcbsp *mcbsp = snd_soc_dai_get_drvdata(cpu_dai); > + struct pm_qos_request *pm_qos_req = &mcbsp->pm_qos_req; > + int tx = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK); > + int stream1 = tx ? SNDRV_PCM_STREAM_PLAYBACK : SNDRV_PCM_STREAM_CAPTURE; > + int stream2 = tx ? SNDRV_PCM_STREAM_CAPTURE : SNDRV_PCM_STREAM_PLAYBACK; > + int latency = mcbsp->latency[stream2]; > + > + /* Prevent omap hardware from hitting off between FIFO fills */ > + if (!latency || mcbsp->latency[stream1] < latency) > + latency = mcbsp->latency[stream1]; > + > + if (pm_qos_request_active(pm_qos_req)) > + pm_qos_update_request(pm_qos_req, latency); > + else if (latency) > + pm_qos_add_request(pm_qos_req, PM_QOS_CPU_DMA_LATENCY, latency); > + > + return 0; > +} > + > static int omap_mcbsp_dai_trigger(struct snd_pcm_substream *substream, int cmd, > struct snd_soc_dai *cpu_dai) > { > @@ -226,6 +259,7 @@ static int omap_mcbsp_dai_hw_params(struct snd_pcm_substream *substream, > int wlen, channels, wpf; > int pkt_size = 0; > unsigned int format, div, framesize, master; > + unsigned int buffer_size = mcbsp->pdata->buffer_size; > > dma_data = snd_soc_dai_get_dma_data(cpu_dai, substream); > channels = params_channels(params); > @@ -240,7 +274,9 @@ static int omap_mcbsp_dai_hw_params(struct snd_pcm_substream *substream, > default: > return -EINVAL; > } > - if (mcbsp->pdata->buffer_size) { > + if (buffer_size) { > + int latency; > + > if (mcbsp->dma_op_mode == MCBSP_DMA_MODE_THRESHOLD) { > int period_words, max_thrsh; > int divider = 0; > @@ -271,6 +307,12 @@ static int omap_mcbsp_dai_hw_params(struct snd_pcm_substream *substream, > /* Use packet mode for non mono streams */ > pkt_size = channels; > } > + > + latency = ((((buffer_size - pkt_size) / channels) * 1000) > + / (params->rate_num / params->rate_den)); > + > + mcbsp->latency[substream->stream] = latency; > + > omap_mcbsp_set_threshold(substream, pkt_size); > } > > @@ -554,6 +596,7 @@ static int omap_mcbsp_dai_set_dai_sysclk(struct snd_soc_dai *cpu_dai, > static const struct snd_soc_dai_ops mcbsp_dai_ops = { > .startup = omap_mcbsp_dai_startup, > .shutdown = omap_mcbsp_dai_shutdown, > + .prepare = omap_mcbsp_dai_prepare, > .trigger = omap_mcbsp_dai_trigger, > .delay = omap_mcbsp_dai_delay, > .hw_params = omap_mcbsp_dai_hw_params, > @@ -835,6 +878,9 @@ static int asoc_mcbsp_remove(struct platform_device *pdev) > if (mcbsp->pdata->ops && mcbsp->pdata->ops->free) > mcbsp->pdata->ops->free(mcbsp->id); > > + if (pm_qos_request_active(&mcbsp->pm_qos_req)) > + pm_qos_remove_request(&mcbsp->pm_qos_req); > + > omap_mcbsp_cleanup(mcbsp); > > clk_put(mcbsp->fclk); > -- Péter _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
