On 01/11/2017 07:46 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/ > > Cc: Tony Lindgren <tony@xxxxxxxxxxx> > Cc: Peter Ujfalusi <peter.ujfalusi@xxxxxx> > Signed-off-by: Matt Ranostay <matt@ranostay.consulting> > --- > hanges 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 > > sound/soc/omap/mcbsp.c | 4 ++++ > sound/soc/omap/mcbsp.h | 3 +++ > sound/soc/omap/omap-mcbsp.c | 44 +++++++++++++++++++++++++++++++++++++++++++- > 3 files changed, 50 insertions(+), 1 deletion(-) > > diff --git a/sound/soc/omap/mcbsp.c b/sound/soc/omap/mcbsp.c > index 06fec5699cc8..e1c3d21dc5ed 100644 > --- a/sound/soc/omap/mcbsp.c > +++ b/sound/soc/omap/mcbsp.c > @@ -25,6 +25,7 @@ > #include <linux/io.h> > #include <linux/slab.h> > #include <linux/pm_runtime.h> > +#include <linux/pm_qos.h> > > #include <linux/platform_data/asoc-ti-mcbsp.h> > > @@ -1098,6 +1099,9 @@ int omap_mcbsp_init(struct platform_device *pdev) > > void omap_mcbsp_cleanup(struct omap_mcbsp *mcbsp) > { > + if (pm_qos_request_active(&mcbsp->pm_qos_req)) > + pm_qos_remove_request(&mcbsp->pm_qos_req); > + It might be better to do this in asoc_mcbsp_remove() in omap-mcbsp.c so the pm_qos stuff is handled within one file. > if (mcbsp->pdata->buffer_size) > sysfs_remove_group(&mcbsp->dev->kobj, &additional_attr_group); > > 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..3814a234ef61 100644 > --- a/sound/soc/omap/omap-mcbsp.c > +++ b/sound/soc/omap/omap-mcbsp.c #include <linux/pm_qos.h> ? -- Péter -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
