| Message ID | 20241106193413.1730413-16-quic_wcheng@quicinc.com |
|---|---|
| State | New |
| Headers | show |
| Series | Introduce QC USB SND audio offloading support | expand |
Hi Takashi, On 11/20/2024 4:23 AM, Takashi Iwai wrote: > On Wed, 06 Nov 2024 20:33:58 +0100, > Wesley Cheng wrote: >> USB SND needs to know how the USB offload path is being routed. This would >> allow for applications to open the corresponding sound card and pcm device >> when it wants to take the audio offload path. This callback should return >> the mapped indexes based on the USB SND device information. >> >> Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> >> Signed-off-by: Wesley Cheng <quic_wcheng@quicinc.com> >> --- >> include/sound/soc-usb.h | 16 ++++++++++++++++ >> sound/soc/soc-usb.c | 34 ++++++++++++++++++++++++++++++++++ >> 2 files changed, 50 insertions(+) >> >> diff --git a/include/sound/soc-usb.h b/include/sound/soc-usb.h >> index 587ea07a8cf5..c3d3e8d62ac5 100644 >> --- a/include/sound/soc-usb.h >> +++ b/include/sound/soc-usb.h >> @@ -36,6 +36,11 @@ struct snd_soc_usb_device { >> * @list - list head for SND SOC struct list >> * @component - reference to ASoC component >> * @connection_status_cb - callback to notify connection events >> + * @update_offload_route_info - callback to fetch mapped ASoC card and pcm >> + * device pair. This is unrelated to the concept >> + * of DAPM route. The "route" argument carries >> + * an array used for a kcontrol output and should >> + * contain two integers, card and pcm device index >> * @priv_data - driver data >> **/ >> struct snd_soc_usb { >> @@ -44,6 +49,9 @@ struct snd_soc_usb { >> int (*connection_status_cb)(struct snd_soc_usb *usb, >> struct snd_soc_usb_device *sdev, >> bool connected); >> + int (*update_offload_route_info)(struct snd_soc_component *component, >> + int card, int pcm, int direction, >> + long *route); >> void *priv_data; >> }; >> >> @@ -61,6 +69,8 @@ int snd_soc_usb_setup_offload_jack(struct snd_soc_component *component, >> int snd_soc_usb_disable_offload_jack(struct snd_soc_component *component); >> int snd_soc_usb_enable_offload_jack(struct snd_soc_component *component, >> struct snd_soc_jack *jack); >> +int snd_soc_usb_update_offload_route(struct device *dev, int card, int pcm, >> + int direction, long *route); >> >> struct snd_soc_usb *snd_soc_usb_allocate_port(struct snd_soc_component *component, >> void *data); >> @@ -109,6 +119,12 @@ static inline int snd_soc_usb_enable_offload_jack(struct snd_soc_component *comp >> return 0; >> } >> >> +static int snd_soc_usb_update_offload_route(struct device *dev, int card, int pcm, >> + int direction, long *route) >> +{ >> + return -ENODEV; >> +} >> + >> static inline struct snd_soc_usb * >> snd_soc_usb_allocate_port(struct snd_soc_component *component, void *data) >> { >> diff --git a/sound/soc/soc-usb.c b/sound/soc/soc-usb.c >> index ab914878e101..e56826f1df71 100644 >> --- a/sound/soc/soc-usb.c >> +++ b/sound/soc/soc-usb.c >> @@ -145,6 +145,40 @@ int snd_soc_usb_enable_offload_jack(struct snd_soc_component *component, >> } >> EXPORT_SYMBOL_GPL(snd_soc_usb_enable_offload_jack); >> >> +/** >> + * snd_soc_usb_update_offload_route - Find active USB offload path >> + * @dev - USB device to get offload status >> + * @card - USB card index >> + * @pcm - USB PCM device index >> + * @direction - playback or capture direction >> + * @route - pointer to route output array >> + * >> + * Fetch the current status for the USB SND card and PCM device indexes >> + * specified. The "route" argument should be an array of integers being >> + * used for a kcontrol output. The first element should have the selected >> + * card index, and the second element should have the selected pcm device >> + * index. >> + */ >> +int snd_soc_usb_update_offload_route(struct device *dev, int card, int pcm, >> + int direction, long *route) >> +{ >> + struct snd_soc_usb *ctx; >> + int ret = -EINVAL; >> + >> + ctx = snd_soc_find_usb_ctx(dev); >> + if (!ctx) >> + return -ENODEV; >> + >> + mutex_lock(&ctx_mutex); >> + if (ctx && ctx->update_offload_route_info) >> + ret = ctx->update_offload_route_info(ctx->component, card, pcm, >> + direction, route); >> + mutex_unlock(&ctx_mutex); > The second ctx check is redundant. And the locking scheme looks > dubious -- as ctx isn't protected by ctx_mutex after its retrieval via > snd_soc_find_usb_ctx(), even if you reacquire ctx_mutex, it may point > to an already released object (in theory). > > IOW, for a safer protection, you'd need to cover the whole > find-and-exec procedure via a single ctx_mutex lock action. > That's fair, will make the change to move the mutexes around. Thanks Wesley Cheng
diff --git a/include/sound/soc-usb.h b/include/sound/soc-usb.h index 587ea07a8cf5..c3d3e8d62ac5 100644 --- a/include/sound/soc-usb.h +++ b/include/sound/soc-usb.h @@ -36,6 +36,11 @@ struct snd_soc_usb_device { * @list - list head for SND SOC struct list * @component - reference to ASoC component * @connection_status_cb - callback to notify connection events + * @update_offload_route_info - callback to fetch mapped ASoC card and pcm + * device pair. This is unrelated to the concept + * of DAPM route. The "route" argument carries + * an array used for a kcontrol output and should + * contain two integers, card and pcm device index * @priv_data - driver data **/ struct snd_soc_usb { @@ -44,6 +49,9 @@ struct snd_soc_usb { int (*connection_status_cb)(struct snd_soc_usb *usb, struct snd_soc_usb_device *sdev, bool connected); + int (*update_offload_route_info)(struct snd_soc_component *component, + int card, int pcm, int direction, + long *route); void *priv_data; }; @@ -61,6 +69,8 @@ int snd_soc_usb_setup_offload_jack(struct snd_soc_component *component, int snd_soc_usb_disable_offload_jack(struct snd_soc_component *component); int snd_soc_usb_enable_offload_jack(struct snd_soc_component *component, struct snd_soc_jack *jack); +int snd_soc_usb_update_offload_route(struct device *dev, int card, int pcm, + int direction, long *route); struct snd_soc_usb *snd_soc_usb_allocate_port(struct snd_soc_component *component, void *data); @@ -109,6 +119,12 @@ static inline int snd_soc_usb_enable_offload_jack(struct snd_soc_component *comp return 0; } +static int snd_soc_usb_update_offload_route(struct device *dev, int card, int pcm, + int direction, long *route) +{ + return -ENODEV; +} + static inline struct snd_soc_usb * snd_soc_usb_allocate_port(struct snd_soc_component *component, void *data) { diff --git a/sound/soc/soc-usb.c b/sound/soc/soc-usb.c index ab914878e101..e56826f1df71 100644 --- a/sound/soc/soc-usb.c +++ b/sound/soc/soc-usb.c @@ -145,6 +145,40 @@ int snd_soc_usb_enable_offload_jack(struct snd_soc_component *component, } EXPORT_SYMBOL_GPL(snd_soc_usb_enable_offload_jack); +/** + * snd_soc_usb_update_offload_route - Find active USB offload path + * @dev - USB device to get offload status + * @card - USB card index + * @pcm - USB PCM device index + * @direction - playback or capture direction + * @route - pointer to route output array + * + * Fetch the current status for the USB SND card and PCM device indexes + * specified. The "route" argument should be an array of integers being + * used for a kcontrol output. The first element should have the selected + * card index, and the second element should have the selected pcm device + * index. + */ +int snd_soc_usb_update_offload_route(struct device *dev, int card, int pcm, + int direction, long *route) +{ + struct snd_soc_usb *ctx; + int ret = -EINVAL; + + ctx = snd_soc_find_usb_ctx(dev); + if (!ctx) + return -ENODEV; + + mutex_lock(&ctx_mutex); + if (ctx && ctx->update_offload_route_info) + ret = ctx->update_offload_route_info(ctx->component, card, pcm, + direction, route); + mutex_unlock(&ctx_mutex); + + return ret; +} +EXPORT_SYMBOL_GPL(snd_soc_usb_update_offload_route); + /** * snd_soc_usb_find_priv_data() - Retrieve private data stored * @usbdev: device reference