On 12-07-18, 13:02, Srinivas Kandagatla wrote: > Thanks Vinod for taking look at this! > > On 12/07/18 11:59, Vinod wrote: > > On 11-07-18, 09:43, Srinivas Kandagatla wrote: > > > This patch aims at add achieving dynamic behaviour of audio card when > > > the dependent components disappear and reappear. > > > > > > With this patch the card is removed if any of the dependent component > > > is removed and card is added back if the dependent component comes back. > > > All this is done using component framework and matching based on > > > component name. > > > > > > Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx> > > > > Looks fine mostly, some nitpicks below: > > > > > --- > > > > > > During discussion regarding card re-binding when components unregister > > > and register back at https://lkml.org/lkml/2018/7/9/785 it was suggested > > > that component framework can be added into core to provide this feature. > > > > > > With this new changes the card will re-bind once the dependent component > > > re-registers after unregistering. This works based on the match done > > > from component name using component framework. > > > > > > I have tested this patch with qdsp start-stop usecase for more than 10000 > > > times in loop on Qcom platforms. > > > > > > I will send qdsp side cleanup patches once I get some feedback on this patch. > > > > > > > > > include/sound/soc.h | 5 ++++ > > > sound/soc/soc-core.c | 70 ++++++++++++++++++++++++++++++++++++++++++++++++---- > > > 2 files changed, 70 insertions(+), 5 deletions(-) > > > > > > diff --git a/include/sound/soc.h b/include/sound/soc.h > > > index 870ba6b64817..b94149d29c0d 100644 > > > --- a/include/sound/soc.h > > > +++ b/include/sound/soc.h > > > @@ -17,6 +17,7 @@ > > > #include <linux/workqueue.h> > > > #include <linux/interrupt.h> > > > #include <linux/kernel.h> > > > +#include <linux/component.h> > > > #include <linux/regmap.h> > > > #include <linux/log2.h> > > > #include <sound/core.h> > > > @@ -1088,6 +1089,10 @@ struct snd_soc_card { > > > struct work_struct deferred_resume_work; > > > + /* component framework related */ > > > + bool components_added; > > > + struct component_match *match; > > > + > > > /* lists of probed devices belonging to this card */ > > > struct list_head component_dev_list; > > > diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c > > > index 6d33634b934b..377ed8e67686 100644 > > > --- a/sound/soc/soc-core.c > > > +++ b/sound/soc/soc-core.c > > > @@ -279,11 +279,31 @@ static inline void snd_soc_debugfs_exit(void) > > > #endif > > > +static int snd_soc_card_comp_compare(struct device *dev, void *data) > > > > Why not make last arg as name and avoid void * > > > > I can rename argument "data" to "name", but I can not change the prototype > of the compare callback expected by component framework. oh yes the data type can't be changed. > > > > +{ > > > + struct snd_soc_component *component = NULL; > > > + struct snd_soc_component *t; > > > > why do you need two variables for this > > We need two because one is iterator and other is find. > > if we use just one we will endup with valid iterator item which may not have > matched dev. > > Or I can re-organize/simplify the code like this: > > static int snd_soc_card_comp_compare(struct device *dev, void *name) > { > struct snd_soc_component *t; > > lockdep_assert_held(&client_mutex); > list_for_each_entry(t, &component_list, list) { > if (dev == t->dev) { > if (!strcmp(t->name, name)) > return 1; > } > } > > return 0; > } looks better :) > > > > + > > > + lockdep_assert_held(&client_mutex); > > > + list_for_each_entry(t, &component_list, list) { > > > + if (dev == t->dev) { > > > + component = t; > > > > you can skip this line and use t in below code. > > > > > + break; > > > + } > > > + } > > > + > > > + if (component && !strcmp(component->name, data)) > > > > > > strncmp? > > AFAIU, strcmp should be safe here as component->name is generated/sanitized > by core and would be of max len of NAME_SIZE. > core uses strcmp in may places. Any particular reason you want me to move to > strncmp? I agree that name is generated but I don't trust strings :) -- ~Vinod _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
