When USB cable gets disconnected, the undergoing playback/capture
stalls, without any notification to u_audio about the change.
Experiments with a dwc2 gadget revealed that Suspend interrupt is
thrown at cable disconnection, which the gadget framework translates to
calling suspend callback of a function, if it is defined.
Add the suspend callback to f_uac2 function, calling
corresponding method of u_audio in order to stop the respective PCM
streams and to notify subscribed clients at cable disconnection.
Signed-off-by: Pavel Hofman <pavel.hofman@xxxxxxxxxxx>
---
v3: fixed commit title and msg
---
drivers/usb/gadget/function/f_uac2.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c
index 5ee5314780a6..3e6339439b88 100644
--- a/drivers/usb/gadget/function/f_uac2.c
+++ b/drivers/usb/gadget/function/f_uac2.c
@@ -1433,6 +1433,14 @@ afunc_disable(struct usb_function *fn)
usb_ep_disable(uac2->int_ep);
}
+static void
+afunc_suspend(struct usb_function *fn)
+{
+ struct f_uac2 *uac2 = func_to_uac2(fn);
+
+ u_audio_suspend(&uac2->g_audio);
+}
+
static int
in_rq_cur(struct usb_function *fn, const struct usb_ctrlrequest *cr)
{
@@ -2104,6 +2112,7 @@ static struct usb_function *afunc_alloc(struct usb_function_instance *fi)
uac2->g_audio.func.set_alt = afunc_set_alt;
uac2->g_audio.func.get_alt = afunc_get_alt;
uac2->g_audio.func.disable = afunc_disable;
+ uac2->g_audio.func.suspend = afunc_suspend;
uac2->g_audio.func.setup = afunc_setup;
uac2->g_audio.func.free_func = afunc_free;
--
2.25.1
