usb: gadget: f_uac1: Add suspend callback

Add suspend callback to f_uac1 function, calling corresponding method
of u_audio in order to stop the respective PCM streams and to notify
subscribed clients about the stop.
Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
Link: https://lore.kernel.org/r/20220121155308.48794-11-pavel.hofman@ivitera.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/gadget/function/f_uac1.c

@@ -961,6 +961,14 @@ static void f_audio_disable(struct usb_function *f)
 		usb_ep_disable(uac1->int_ep);
 }
 
+static void
+f_audio_suspend(struct usb_function *f)
+{
+	struct f_uac1 *uac1 = func_to_uac1(f);
+
+	u_audio_suspend(&uac1->g_audio);
+}
+
 /*-------------------------------------------------------------------------*/
 static struct uac_feature_unit_descriptor *build_fu_desc(int chmask)
 {
@@ -1691,6 +1699,7 @@ static struct usb_function *f_audio_alloc(struct usb_function_instance *fi)
 	uac1->g_audio.func.get_alt = f_audio_get_alt;
 	uac1->g_audio.func.setup = f_audio_setup;
 	uac1->g_audio.func.disable = f_audio_disable;
+	uac1->g_audio.func.suspend = f_audio_suspend;
 	uac1->g_audio.func.free_func = f_audio_free;
 
 	return &uac1->g_audio.func;