Hi Amadeusz,
On 2/5/2024 1:01 AM, Amadeusz Sławiński wrote:
On 2/3/2024 3:36 AM, Wesley Cheng wrote:
In case of notifying SND platform drivers of connection events, some of
these use cases, such as offloading, require an ASoC USB backend
device to
be initialized before the events can be handled. If the USB backend
device
has not yet been probed, this leads to missing initial USB audio device
connection events.
Expose an API that traverses the usb_chip array for connected devices,
and
to call the respective connection callback registered to the SND platform
driver.
Signed-off-by: Wesley Cheng <quic_wcheng@xxxxxxxxxxx>
---
sound/usb/card.c | 19 +++++++++++++++++++
sound/usb/card.h | 2 ++
sound/usb/qcom/qc_audio_offload.c | 2 ++
3 files changed, 23 insertions(+)
diff --git a/sound/usb/card.c b/sound/usb/card.c
index 11b827b7a2a5..995b2df676ab 100644
--- a/sound/usb/card.c
+++ b/sound/usb/card.c
@@ -202,6 +202,25 @@ struct snd_usb_stream
*snd_usb_find_suppported_substream(int card_idx,
}
EXPORT_SYMBOL_GPL(snd_usb_find_suppported_substream);
+/*
+ * in case the platform driver was not ready at the time of USB SND
+ * device connect, expose an API to discover all connected USB devices
+ * so it can populate any dependent resources/structures.
+ */
+void snd_usb_rediscover_devices(void)
+{
+ int i;
+
+ mutex_lock(®ister_mutex);
+ for (i = 0; i < SNDRV_CARDS; i++) {
+ if (usb_chip[i])
+ if (platform_ops && platform_ops->connect_cb)
+ platform_ops->connect_cb(usb_chip[i]);
if inside if, it can just be && or maybe move callback check before
mutex lock and just return early if it is not present?
Thanks for pointing that out. Makes sense, and will update it.
Thanks
Wesley Cheng
