Merging upstream version 6.8.9.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

14 files changed, 533 insertions, 145 deletions

diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
index fdd0fc7b8f..6bff6cb937 100644
--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -2931,9 +2931,8 @@ static int __ffs_func_bind_do_os_desc(enum ffs_os_desc_type type,
 
 		t = &func->function.os_desc_table[desc->bFirstInterfaceNumber];
 		t->if_id = func->interfaces_nums[desc->bFirstInterfaceNumber];
-		memcpy(t->os_desc->ext_compat_id, &desc->CompatibleID,
-		       ARRAY_SIZE(desc->CompatibleID) +
-		       ARRAY_SIZE(desc->SubCompatibleID));
+		memcpy(t->os_desc->ext_compat_id, &desc->IDs,
+		       sizeof_field(struct usb_ext_compat_desc, IDs));
 		length = sizeof(*desc);
 	}
 		break;
diff --git a/drivers/usb/gadget/function/f_midi.c b/drivers/usb/gadget/function/f_midi.c
index 5335845d69..20c6fbd94f 100644
--- a/drivers/usb/gadget/function/f_midi.c
+++ b/drivers/usb/gadget/function/f_midi.c
@@ -1177,11 +1177,11 @@ F_MIDI_OPT(out_ports, true, MAX_PORTS);
 static ssize_t f_midi_opts_id_show(struct config_item *item, char *page)
 {
 	struct f_midi_opts *opts = to_f_midi_opts(item);
-	int result;
+	ssize_t result;
 
 	mutex_lock(&opts->lock);
 	if (opts->id) {
-		result = strlcpy(page, opts->id, PAGE_SIZE);
+		result = strscpy(page, opts->id, PAGE_SIZE);
 	} else {
 		page[0] = 0;
 		result = 0;
diff --git a/drivers/usb/gadget/function/f_ncm.c b/drivers/usb/gadget/function/f_ncm.c
index f3456b8bf4..0acc32ed99 100644
--- a/drivers/usb/gadget/function/f_ncm.c
+++ b/drivers/usb/gadget/function/f_ncm.c
@@ -103,6 +103,16 @@ static inline struct f_ncm *func_to_ncm(struct usb_function *f)
 /* Delay for the transmit to wait before sending an unfilled NTB frame. */
 #define TX_TIMEOUT_NSECS	300000
 
+/*
+ * Although max mtu as dictated by u_ether is 15412 bytes, setting
+ * max_segment_size to 15426 would not be efficient. If user chooses segment
+ * size to be (>= 8192), then we can't aggregate more than one buffer in each
+ * NTB (assuming each packet coming from network layer is >= 8192 bytes) as ep
+ * maxpacket limit is 16384. So let max_segment_size be limited to 8000 to allow
+ * at least 2 packets to be aggregated reducing wastage of NTB buffer space
+ */
+#define MAX_DATAGRAM_SIZE	8000
+
 #define FORMATS_SUPPORTED	(USB_CDC_NCM_NTB16_SUPPORTED |	\
 				 USB_CDC_NCM_NTB32_SUPPORTED)
 
@@ -179,7 +189,6 @@ static struct usb_cdc_ether_desc ecm_desc = {
 	/* this descriptor actually adds value, surprise! */
 	/* .iMACAddress = DYNAMIC */
 	.bmEthernetStatistics =	cpu_to_le32(0), /* no statistics */
-	.wMaxSegmentSize =	cpu_to_le16(ETH_FRAME_LEN),
 	.wNumberMCFilters =	cpu_to_le16(0),
 	.bNumberPowerFilters =	0,
 };
@@ -869,7 +878,7 @@ static int ncm_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 		if (alt > 1)
 			goto fail;
 
-		if (ncm->port.in_ep->enabled) {
+		if (ncm->netdev) {
 			DBG(cdev, "reset ncm\n");
 			ncm->netdev = NULL;
 			gether_disconnect(&ncm->port);
@@ -1166,11 +1175,15 @@ static int ncm_unwrap_ntb(struct gether *port,
 	struct sk_buff	*skb2;
 	int		ret = -EINVAL;
 	unsigned	ntb_max = le32_to_cpu(ntb_parameters.dwNtbOutMaxSize);
-	unsigned	frame_max = le16_to_cpu(ecm_desc.wMaxSegmentSize);
+	unsigned	frame_max;
 	const struct ndp_parser_opts *opts = ncm->parser_opts;
 	unsigned	crc_len = ncm->is_crc ? sizeof(uint32_t) : 0;
 	int		dgram_counter;
 	int		to_process = skb->len;
+	struct f_ncm_opts *ncm_opts;
+
+	ncm_opts = container_of(port->func.fi, struct f_ncm_opts, func_inst);
+	frame_max = ncm_opts->max_segment_size;
 
 parse_ntb:
 	tmp = (__le16 *)ntb_ptr;
@@ -1354,7 +1367,7 @@ static void ncm_disable(struct usb_function *f)
 
 	DBG(cdev, "ncm deactivated\n");
 
-	if (ncm->port.in_ep->enabled) {
+	if (ncm->netdev) {
 		ncm->netdev = NULL;
 		gether_disconnect(&ncm->port);
 	}
@@ -1438,8 +1451,10 @@ static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
 
 	mutex_lock(&ncm_opts->lock);
 	gether_set_gadget(ncm_opts->net, cdev->gadget);
-	if (!ncm_opts->bound)
+	if (!ncm_opts->bound) {
+		ncm_opts->net->mtu = (ncm_opts->max_segment_size - ETH_HLEN);
 		status = gether_register_netdev(ncm_opts->net);
+	}
 	mutex_unlock(&ncm_opts->lock);
 
 	if (status)
@@ -1482,6 +1497,8 @@ static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
 	ncm_data_intf.bInterfaceNumber = status;
 	ncm_union_desc.bSlaveInterface0 = status;
 
+	ecm_desc.wMaxSegmentSize = cpu_to_le16(ncm_opts->max_segment_size);
+
 	status = -ENODEV;
 
 	/* allocate instance-specific endpoints */
@@ -1584,11 +1601,56 @@ USB_ETHERNET_CONFIGFS_ITEM_ATTR_QMULT(ncm);
 /* f_ncm_opts_ifname */
 USB_ETHERNET_CONFIGFS_ITEM_ATTR_IFNAME(ncm);
 
+static ssize_t ncm_opts_max_segment_size_show(struct config_item *item,
+					      char *page)
+{
+	struct f_ncm_opts *opts = to_f_ncm_opts(item);
+	u16 segment_size;
+
+	mutex_lock(&opts->lock);
+	segment_size = opts->max_segment_size;
+	mutex_unlock(&opts->lock);
+
+	return sysfs_emit(page, "%u\n", segment_size);
+}
+
+static ssize_t ncm_opts_max_segment_size_store(struct config_item *item,
+					       const char *page, size_t len)
+{
+	struct f_ncm_opts *opts = to_f_ncm_opts(item);
+	u16 segment_size;
+	int ret;
+
+	mutex_lock(&opts->lock);
+	if (opts->refcnt) {
+		ret = -EBUSY;
+		goto out;
+	}
+
+	ret = kstrtou16(page, 0, &segment_size);
+	if (ret)
+		goto out;
+
+	if (segment_size > MAX_DATAGRAM_SIZE) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	opts->max_segment_size = segment_size;
+	ret = len;
+out:
+	mutex_unlock(&opts->lock);
+	return ret;
+}
+
+CONFIGFS_ATTR(ncm_opts_, max_segment_size);
+
 static struct configfs_attribute *ncm_attrs[] = {
 	&ncm_opts_attr_dev_addr,
 	&ncm_opts_attr_host_addr,
 	&ncm_opts_attr_qmult,
 	&ncm_opts_attr_ifname,
+	&ncm_opts_attr_max_segment_size,
 	NULL,
 };
 
@@ -1631,6 +1693,7 @@ static struct usb_function_instance *ncm_alloc_inst(void)
 		kfree(opts);
 		return ERR_CAST(net);
 	}
+	opts->max_segment_size = ETH_FRAME_LEN;
 	INIT_LIST_HEAD(&opts->ncm_os_desc.ext_prop);
 
 	descs[0] = &opts->ncm_os_desc;
diff --git a/drivers/usb/gadget/function/f_tcm.c b/drivers/usb/gadget/function/f_tcm.c
index ff33f31bcd..37befd6db0 100644
--- a/drivers/usb/gadget/function/f_tcm.c
+++ b/drivers/usb/gadget/function/f_tcm.c
@@ -1504,8 +1504,8 @@ static ssize_t tcm_usbg_tpg_nexus_show(struct config_item *item, char *page)
 		ret = -ENODEV;
 		goto out;
 	}
-	ret = snprintf(page, PAGE_SIZE, "%s\n",
-			tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
+	ret = sysfs_emit(page, "%s\n",
+			 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
 out:
 	mutex_unlock(&tpg->tpg_mutex);
 	return ret;
diff --git a/drivers/usb/gadget/function/f_uac1.c b/drivers/usb/gadget/function/f_uac1.c
index 6f0e1d803d..7de74a3dd3 100644
--- a/drivers/usb/gadget/function/f_uac1.c
+++ b/drivers/usb/gadget/function/f_uac1.c
@@ -292,6 +292,77 @@ static struct usb_descriptor_header *f_audio_desc[] = {
 	NULL,
 };
 
+/* Standard ISO OUT Endpoint Descriptor */
+static struct usb_endpoint_descriptor ss_as_out_ep_desc  = {
+	.bLength =		USB_DT_ENDPOINT_AUDIO_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+	.bEndpointAddress =	USB_DIR_OUT,
+	.bmAttributes =		USB_ENDPOINT_SYNC_ADAPTIVE
+				| USB_ENDPOINT_XFER_ISOC,
+	.wMaxPacketSize	=	cpu_to_le16(UAC1_OUT_EP_MAX_PACKET_SIZE),
+	.bInterval =		4,
+};
+
+static struct usb_ss_ep_comp_descriptor ss_as_out_ep_desc_comp = {
+	.bLength		= sizeof(ss_as_out_ep_desc_comp),
+	.bDescriptorType	= USB_DT_SS_ENDPOINT_COMP,
+	.bMaxBurst		= 0,
+	.bmAttributes		= 0,
+	/* wBytesPerInterval = DYNAMIC */
+};
+
+/* Standard ISO OUT Endpoint Descriptor */
+static struct usb_endpoint_descriptor ss_as_in_ep_desc  = {
+	.bLength =		USB_DT_ENDPOINT_AUDIO_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+	.bEndpointAddress =	USB_DIR_IN,
+	.bmAttributes =		USB_ENDPOINT_SYNC_ASYNC
+				| USB_ENDPOINT_XFER_ISOC,
+	.wMaxPacketSize	=	cpu_to_le16(UAC1_OUT_EP_MAX_PACKET_SIZE),
+	.bInterval =		4,
+};
+
+static struct usb_ss_ep_comp_descriptor ss_as_in_ep_desc_comp = {
+	.bLength		= sizeof(ss_as_in_ep_desc_comp),
+	.bDescriptorType	= USB_DT_SS_ENDPOINT_COMP,
+	.bMaxBurst		= 0,
+	.bmAttributes		= 0,
+	/* wBytesPerInterval = DYNAMIC */
+};
+
+static struct usb_descriptor_header *f_audio_ss_desc[] = {
+	(struct usb_descriptor_header *)&ac_interface_desc,
+	(struct usb_descriptor_header *)&ac_header_desc,
+
+	(struct usb_descriptor_header *)&usb_out_it_desc,
+	(struct usb_descriptor_header *)&io_out_ot_desc,
+	(struct usb_descriptor_header *)&io_in_it_desc,
+	(struct usb_descriptor_header *)&usb_in_ot_desc,
+
+	(struct usb_descriptor_header *)&as_out_interface_alt_0_desc,
+	(struct usb_descriptor_header *)&as_out_interface_alt_1_desc,
+	(struct usb_descriptor_header *)&as_out_header_desc,
+
+	(struct usb_descriptor_header *)&as_out_type_i_desc,
+
+	//(struct usb_descriptor_header *)&as_out_ep_desc,
+	(struct usb_descriptor_header *)&ss_as_out_ep_desc,
+	(struct usb_descriptor_header *)&ss_as_out_ep_desc_comp,
+	(struct usb_descriptor_header *)&as_iso_out_desc,
+
+	(struct usb_descriptor_header *)&as_in_interface_alt_0_desc,
+	(struct usb_descriptor_header *)&as_in_interface_alt_1_desc,
+	(struct usb_descriptor_header *)&as_in_header_desc,
+
+	(struct usb_descriptor_header *)&as_in_type_i_desc,
+
+	//(struct usb_descriptor_header *)&as_in_ep_desc,
+	(struct usb_descriptor_header *)&ss_as_in_ep_desc,
+	(struct usb_descriptor_header *)&ss_as_in_ep_desc_comp,
+	(struct usb_descriptor_header *)&as_iso_in_desc,
+	NULL,
+};
+
 enum {
 	STR_AC_IF,
 	STR_USB_OUT_IT,
@@ -1352,6 +1423,7 @@ static int f_audio_bind(struct usb_configuration *c, struct usb_function *f)
 		ep = usb_ep_autoconfig(cdev->gadget, &as_out_ep_desc);
 		if (!ep)
 			goto err_free_fu;
+		ss_as_out_ep_desc.bEndpointAddress = as_out_ep_desc.bEndpointAddress;
 		audio->out_ep = ep;
 		audio->out_ep->desc = &as_out_ep_desc;
 	}
@@ -1360,6 +1432,7 @@ static int f_audio_bind(struct usb_configuration *c, struct usb_function *f)
 		ep = usb_ep_autoconfig(cdev->gadget, &as_in_ep_desc);
 		if (!ep)
 			goto err_free_fu;
+		ss_as_in_ep_desc.bEndpointAddress = as_in_ep_desc.bEndpointAddress;
 		audio->in_ep = ep;
 		audio->in_ep->desc = &as_in_ep_desc;
 	}
@@ -1367,8 +1440,8 @@ static int f_audio_bind(struct usb_configuration *c, struct usb_function *f)
 	setup_descriptor(audio_opts);
 
 	/* copy descriptors, and track endpoint copies */
-	status = usb_assign_descriptors(f, f_audio_desc, f_audio_desc, NULL,
-					NULL);
+	status = usb_assign_descriptors(f, f_audio_desc, f_audio_desc, f_audio_ss_desc,
+					f_audio_ss_desc);
 	if (status)
 		goto err_free_fu;
 
@@ -1561,7 +1634,7 @@ static ssize_t f_uac1_opts_##name##_show(struct config_item *item,	\
 	int result;							\
 									\
 	mutex_lock(&opts->lock);					\
-	result = snprintf(page, sizeof(opts->name), "%s", opts->name);	\
+	result = scnprintf(page, sizeof(opts->name), "%s", opts->name);	\
 	mutex_unlock(&opts->lock);					\
 									\
 	return result;							\
@@ -1579,7 +1652,7 @@ static ssize_t f_uac1_opts_##name##_store(struct config_item *item,	\
 		goto end;						\
 	}								\
 									\
-	ret = snprintf(opts->name, min(sizeof(opts->name), len),	\
+	ret = scnprintf(opts->name, min(sizeof(opts->name), len),	\
 			"%s", page);					\
 									\
 end:									\
@@ -1685,7 +1758,7 @@ static struct usb_function_instance *f_audio_alloc_inst(void)
 
 	opts->req_number = UAC1_DEF_REQ_NUM;
 
-	snprintf(opts->function_name, sizeof(opts->function_name), "AC Interface");
+	scnprintf(opts->function_name, sizeof(opts->function_name), "AC Interface");
 
 	return &opts->func_inst;
 }
diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c
index f9a0f07a74..383f6854cf 100644
--- a/drivers/usb/gadget/function/f_uac2.c
+++ b/drivers/usb/gadget/function/f_uac2.c
@@ -2045,7 +2045,7 @@ static ssize_t f_uac2_opts_##name##_show(struct config_item *item,	\
 	int result;							\
 									\
 	mutex_lock(&opts->lock);					\
-	result = snprintf(page, sizeof(opts->name), "%s", opts->name);	\
+	result = scnprintf(page, sizeof(opts->name), "%s", opts->name);	\
 	mutex_unlock(&opts->lock);					\
 									\
 	return result;							\
@@ -2063,7 +2063,7 @@ static ssize_t f_uac2_opts_##name##_store(struct config_item *item,	\
 		goto end;						\
 	}								\
 									\
-	ret = snprintf(opts->name, min(sizeof(opts->name), len),	\
+	ret = scnprintf(opts->name, min(sizeof(opts->name), len),	\
 			"%s", page);					\
 									\
 end:									\
@@ -2187,7 +2187,7 @@ static struct usb_function_instance *afunc_alloc_inst(void)
 	opts->req_number = UAC2_DEF_REQ_NUM;
 	opts->fb_max = FBACK_FAST_MAX;
 
-	snprintf(opts->function_name, sizeof(opts->function_name), "Source/Sink");
+	scnprintf(opts->function_name, sizeof(opts->function_name), "Source/Sink");
 
 	opts->p_terminal_type = UAC2_DEF_P_TERM_TYPE;
 	opts->c_terminal_type = UAC2_DEF_C_TERM_TYPE;
diff --git a/drivers/usb/gadget/function/f_uvc.c b/drivers/usb/gadget/function/f_uvc.c
index c6965e3894..929666805b 100644
--- a/drivers/usb/gadget/function/f_uvc.c
+++ b/drivers/usb/gadget/function/f_uvc.c
@@ -263,10 +263,13 @@ uvc_function_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 	return 0;
 }
 
-void uvc_function_setup_continue(struct uvc_device *uvc)
+void uvc_function_setup_continue(struct uvc_device *uvc, int disable_ep)
 {
 	struct usb_composite_dev *cdev = uvc->func.config->cdev;
 
+	if (disable_ep && uvc->video.ep)
+		usb_ep_disable(uvc->video.ep);
+
 	usb_composite_setup_continue(cdev);
 }
 
@@ -337,15 +340,11 @@ uvc_function_set_alt(struct usb_function *f, unsigned interface, unsigned alt)
 		if (uvc->state != UVC_STATE_STREAMING)
 			return 0;
 
-		if (uvc->video.ep)
-			usb_ep_disable(uvc->video.ep);
-
 		memset(&v4l2_event, 0, sizeof(v4l2_event));
 		v4l2_event.type = UVC_EVENT_STREAMOFF;
 		v4l2_event_queue(&uvc->vdev, &v4l2_event);
 
-		uvc->state = UVC_STATE_CONNECTED;
-		return 0;
+		return USB_GADGET_DELAYED_STATUS;
 
 	case 1:
 		if (uvc->state != UVC_STATE_CONNECTED)
diff --git a/drivers/usb/gadget/function/f_uvc.h b/drivers/usb/gadget/function/f_uvc.h
index 1db972d4be..083aef0c65 100644
--- a/drivers/usb/gadget/function/f_uvc.h
+++ b/drivers/usb/gadget/function/f_uvc.h
@@ -11,7 +11,7 @@
 
 struct uvc_device;
 
-void uvc_function_setup_continue(struct uvc_device *uvc);
+void uvc_function_setup_continue(struct uvc_device *uvc, int disable_ep);
 
 void uvc_function_connect(struct uvc_device *uvc);
 
diff --git a/drivers/usb/gadget/function/u_ncm.h b/drivers/usb/gadget/function/u_ncm.h
index 5408854d84..49ec095cdb 100644
--- a/drivers/usb/gadget/function/u_ncm.h
+++ b/drivers/usb/gadget/function/u_ncm.h
@@ -31,6 +31,8 @@ struct f_ncm_opts {
 	 */
 	struct mutex			lock;
 	int				refcnt;
+
+	u16				max_segment_size;
 };
 
 #endif /* U_NCM_H */
diff --git a/drivers/usb/gadget/function/uvc.h b/drivers/usb/gadget/function/uvc.h
index 6751de8b63..cb35687b11 100644
--- a/drivers/usb/gadget/function/uvc.h
+++ b/drivers/usb/gadget/function/uvc.h
@@ -81,6 +81,7 @@ struct uvc_request {
 	struct sg_table sgt;
 	u8 header[UVCG_REQUEST_HEADER_LEN];
 	struct uvc_buffer *last_buf;
+	struct list_head list;
 };
 
 struct uvc_video {
@@ -101,9 +102,18 @@ struct uvc_video {
 	unsigned int uvc_num_requests;
 
 	/* Requests */
+	bool is_enabled; /* tracks whether video stream is enabled */
 	unsigned int req_size;
-	struct uvc_request *ureq;
+	struct list_head ureqs; /* all uvc_requests allocated by uvc_video */
+
+	/* USB requests that the video pump thread can encode into */
 	struct list_head req_free;
+
+	/*
+	 * USB requests video pump thread has already encoded into. These are
+	 * ready to be queued to the endpoint.
+	 */
+	struct list_head req_ready;
 	spinlock_t req_lock;
 
 	unsigned int req_int_count;
@@ -177,7 +187,7 @@ struct uvc_file_handle {
  * Functions
  */
 
-extern void uvc_function_setup_continue(struct uvc_device *uvc);
+extern void uvc_function_setup_continue(struct uvc_device *uvc, int disable_ep);
 extern void uvc_function_connect(struct uvc_device *uvc);
 extern void uvc_function_disconnect(struct uvc_device *uvc);
 
diff --git a/drivers/usb/gadget/function/uvc_configfs.c b/drivers/usb/gadget/function/uvc_configfs.c
index 9bf0e985ac..7e704b2bcf 100644
--- a/drivers/usb/gadget/function/uvc_configfs.c
+++ b/drivers/usb/gadget/function/uvc_configfs.c
@@ -3414,7 +3414,7 @@ static ssize_t f_uvc_opts_string_##cname##_show(struct config_item *item,\
 	int result;							\
 									\
 	mutex_lock(&opts->lock);					\
-	result = snprintf(page, sizeof(opts->aname), "%s", opts->aname);\
+	result = scnprintf(page, sizeof(opts->aname), "%s", opts->aname);\
 	mutex_unlock(&opts->lock);					\
 									\
 	return result;							\
diff --git a/drivers/usb/gadget/function/uvc_v4l2.c b/drivers/usb/gadget/function/uvc_v4l2.c
index 3f0a9795c0..c7e5fa4f29 100644
--- a/drivers/usb/gadget/function/uvc_v4l2.c
+++ b/drivers/usb/gadget/function/uvc_v4l2.c
@@ -443,7 +443,7 @@ uvc_v4l2_streamon(struct file *file, void *fh, enum v4l2_buf_type type)
 		return -EINVAL;
 
 	/* Enable UVC video. */
-	ret = uvcg_video_enable(video, 1);
+	ret = uvcg_video_enable(video);
 	if (ret < 0)
 		return ret;
 
@@ -451,7 +451,7 @@ uvc_v4l2_streamon(struct file *file, void *fh, enum v4l2_buf_type type)
 	 * Complete the alternate setting selection setup phase now that
 	 * userspace is ready to provide video frames.
 	 */
-	uvc_function_setup_continue(uvc);
+	uvc_function_setup_continue(uvc, 0);
 	uvc->state = UVC_STATE_STREAMING;
 
 	return 0;
@@ -463,11 +463,18 @@ uvc_v4l2_streamoff(struct file *file, void *fh, enum v4l2_buf_type type)
 	struct video_device *vdev = video_devdata(file);
 	struct uvc_device *uvc = video_get_drvdata(vdev);
 	struct uvc_video *video = &uvc->video;
+	int ret = 0;
 
 	if (type != video->queue.queue.type)
 		return -EINVAL;
 
-	return uvcg_video_enable(video, 0);
+	ret = uvcg_video_disable(video);
+	if (ret < 0)
+		return ret;
+
+	uvc->state = UVC_STATE_CONNECTED;
+	uvc_function_setup_continue(uvc, 1);
+	return 0;
 }
 
 static int
@@ -500,7 +507,7 @@ uvc_v4l2_subscribe_event(struct v4l2_fh *fh,
 static void uvc_v4l2_disable(struct uvc_device *uvc)
 {
 	uvc_function_disconnect(uvc);
-	uvcg_video_enable(&uvc->video, 0);
+	uvcg_video_disable(&uvc->video);
 	uvcg_free_buffers(&uvc->video.queue);
 	uvc->func_connected = false;
 	wake_up_interruptible(&uvc->func_connected_queue);
@@ -647,4 +654,3 @@ const struct v4l2_file_operations uvc_v4l2_fops = {
 	.get_unmapped_area = uvcg_v4l2_get_unmapped_area,
 #endif
 };
-
diff --git a/drivers/usb/gadget/function/uvc_video.c b/drivers/usb/gadget/function/uvc_video.c
index 91af3b1ef0..53e4cd81ea 100644
--- a/drivers/usb/gadget/function/uvc_video.c
+++ b/drivers/usb/gadget/function/uvc_video.c
@@ -35,6 +35,9 @@ uvc_video_encode_header(struct uvc_video *video, struct uvc_buffer *buf,
 
 	data[1] = UVC_STREAM_EOH | video->fid;
 
+	if (video->queue.flags & UVC_QUEUE_DROP_INCOMPLETE)
+		data[1] |= UVC_STREAM_ERR;
+
 	if (video->queue.buf_used == 0 && ts.tv_sec) {
 		/* dwClockFrequency is 48 MHz */
 		u32 pts = ((u64)ts.tv_sec * USEC_PER_SEC + ts.tv_nsec / NSEC_PER_USEC) * 48;
@@ -227,6 +230,28 @@ uvc_video_encode_isoc(struct usb_request *req, struct uvc_video *video,
  * Request handling
  */
 
+/*
+ * Callers must take care to hold req_lock when this function may be called
+ * from multiple threads. For example, when frames are streaming to the host.
+ */
+static void
+uvc_video_free_request(struct uvc_request *ureq, struct usb_ep *ep)
+{
+	sg_free_table(&ureq->sgt);
+	if (ureq->req && ep) {
+		usb_ep_free_request(ep, ureq->req);
+		ureq->req = NULL;
+	}
+
+	kfree(ureq->req_buffer);
+	ureq->req_buffer = NULL;
+
+	if (!list_empty(&ureq->list))
+		list_del_init(&ureq->list);
+
+	kfree(ureq);
+}
+
 static int uvcg_video_ep_queue(struct uvc_video *video, struct usb_request *req)
 {
 	int ret;
@@ -247,14 +272,127 @@ static int uvcg_video_ep_queue(struct uvc_video *video, struct usb_request *req)
 	return ret;
 }
 
+/* This function must be called with video->req_lock held. */
+static int uvcg_video_usb_req_queue(struct uvc_video *video,
+	struct usb_request *req, bool queue_to_ep)
+{
+	bool is_bulk = video->max_payload_size;
+	struct list_head *list = NULL;
+
+	if (!video->is_enabled)
+		return -ENODEV;
+
+	if (queue_to_ep) {
+		struct uvc_request *ureq = req->context;
+		/*
+		 * With USB3 handling more requests at a higher speed, we can't
+		 * afford to generate an interrupt for every request. Decide to
+		 * interrupt:
+		 *
+		 * - When no more requests are available in the free queue, as
+		 *   this may be our last chance to refill the endpoint's
+		 *   request queue.
+		 *
+		 * - When this is request is the last request for the video
+		 *   buffer, as we want to start sending the next video buffer
+		 *   ASAP in case it doesn't get started already in the next
+		 *   iteration of this loop.
+		 *
+		 * - Four times over the length of the requests queue (as
+		 *   indicated by video->uvc_num_requests), as a trade-off
+		 *   between latency and interrupt load.
+		 */
+		if (list_empty(&video->req_free) || ureq->last_buf ||
+			!(video->req_int_count %
+			DIV_ROUND_UP(video->uvc_num_requests, 4))) {
+			video->req_int_count = 0;
+			req->no_interrupt = 0;
+		} else {
+			req->no_interrupt = 1;
+		}
+		video->req_int_count++;
+		return uvcg_video_ep_queue(video, req);
+	}
+	/*
+	 * If we're not queuing to the ep, for isoc we're queuing
+	 * to the req_ready list, otherwise req_free.
+	 */
+	list = is_bulk ? &video->req_free : &video->req_ready;
+	list_add_tail(&req->list, list);
+	return 0;
+}
+
+/*
+ * Must only be called from uvcg_video_enable - since after that we only want to
+ * queue requests to the endpoint from the uvc_video_complete complete handler.
+ * This function is needed in order to 'kick start' the flow of requests from
+ * gadget driver to the usb controller.
+ */
+static void uvc_video_ep_queue_initial_requests(struct uvc_video *video)
+{
+	struct usb_request *req = NULL;
+	unsigned long flags = 0;
+	unsigned int count = 0;
+	int ret = 0;
+
+	/*
+	 * We only queue half of the free list since we still want to have
+	 * some free usb_requests in the free list for the video_pump async_wq
+	 * thread to encode uvc buffers into. Otherwise we could get into a
+	 * situation where the free list does not have any usb requests to
+	 * encode into - we always end up queueing 0 length requests to the
+	 * end point.
+	 */
+	unsigned int half_list_size = video->uvc_num_requests / 2;
+
+	spin_lock_irqsave(&video->req_lock, flags);
+	/*
+	 * Take these requests off the free list and queue them all to the
+	 * endpoint. Since we queue 0 length requests with the req_lock held,
+	 * there isn't any 'data' race involved here with the complete handler.
+	 */
+	while (count < half_list_size) {
+		req = list_first_entry(&video->req_free, struct usb_request,
+					list);
+		list_del(&req->list);
+		req->length = 0;
+		ret = uvcg_video_ep_queue(video, req);
+		if (ret < 0) {
+			uvcg_queue_cancel(&video->queue, 0);
+			break;
+		}
+		count++;
+	}
+	spin_unlock_irqrestore(&video->req_lock, flags);
+}
+
 static void
 uvc_video_complete(struct usb_ep *ep, struct usb_request *req)
 {
 	struct uvc_request *ureq = req->context;
 	struct uvc_video *video = ureq->video;
 	struct uvc_video_queue *queue = &video->queue;
-	struct uvc_device *uvc = video->uvc;
+	struct uvc_buffer *last_buf;
 	unsigned long flags;
+	bool is_bulk = video->max_payload_size;
+	int ret = 0;
+
+	spin_lock_irqsave(&video->req_lock, flags);
+	if (!video->is_enabled) {
+		/*
+		 * When is_enabled is false, uvcg_video_disable() ensures
+		 * that in-flight uvc_buffers are returned, so we can
+		 * safely call free_request without worrying about
+		 * last_buf.
+		 */
+		uvc_video_free_request(ureq, ep);
+		spin_unlock_irqrestore(&video->req_lock, flags);
+		return;
+	}
+
+	last_buf = ureq->last_buf;
+	ureq->last_buf = NULL;
+	spin_unlock_irqrestore(&video->req_lock, flags);
 
 	switch (req->status) {
 	case 0:
@@ -277,44 +415,85 @@ uvc_video_complete(struct usb_ep *ep, struct usb_request *req)
 		uvcg_queue_cancel(queue, 0);
 	}
 
-	if (ureq->last_buf) {
-		uvcg_complete_buffer(&video->queue, ureq->last_buf);
-		ureq->last_buf = NULL;
+	if (last_buf) {
+		spin_lock_irqsave(&queue->irqlock, flags);
+		uvcg_complete_buffer(queue, last_buf);
+		spin_unlock_irqrestore(&queue->irqlock, flags);
 	}
 
 	spin_lock_irqsave(&video->req_lock, flags);
-	list_add_tail(&req->list, &video->req_free);
+	/*
+	 * Video stream might have been disabled while we were
+	 * processing the current usb_request. So make sure
+	 * we're still streaming before queueing the usb_request
+	 * back to req_free
+	 */
+	if (video->is_enabled) {
+		/*
+		 * Here we check whether any request is available in the ready
+		 * list. If it is, queue it to the ep and add the current
+		 * usb_request to the req_free list - for video_pump to fill in.
+		 * Otherwise, just use the current usb_request to queue a 0
+		 * length request to the ep. Since we always add to the req_free
+		 * list if we dequeue from the ready list, there will never
+		 * be a situation where the req_free list is completely out of
+		 * requests and cannot recover.
+		 */
+		struct usb_request *to_queue = req;
+
+		to_queue->length = 0;
+		if (!list_empty(&video->req_ready)) {
+			to_queue = list_first_entry(&video->req_ready,
+				struct usb_request, list);
+			list_del(&to_queue->list);
+			list_add_tail(&req->list, &video->req_free);
+			/*
+			 * Queue work to the wq as well since it is possible that a
+			 * buffer may not have been completely encoded with the set of
+			 * in-flight usb requests for whih the complete callbacks are
+			 * firing.
+			 * In that case, if we do not queue work to the worker thread,
+			 * the buffer will never be marked as complete - and therefore
+			 * not be returned to userpsace. As a result,
+			 * dequeue -> queue -> dequeue flow of uvc buffers will not
+			 * happen.
+			 */
+			queue_work(video->async_wq, &video->pump);
+		}
+		/*
+		 * Queue to the endpoint. The actual queueing to ep will
+		 * only happen on one thread - the async_wq for bulk endpoints
+		 * and this thread for isoc endpoints.
+		 */
+		ret = uvcg_video_usb_req_queue(video, to_queue, !is_bulk);
+		if (ret < 0) {
+			/*
+			 * Endpoint error, but the stream is still enabled.
+			 * Put request back in req_free for it to be cleaned
+			 * up later.
+			 */
+			list_add_tail(&to_queue->list, &video->req_free);
+		}
+	} else {
+		uvc_video_free_request(ureq, ep);
+		ret = 0;
+	}
 	spin_unlock_irqrestore(&video->req_lock, flags);
-
-	if (uvc->state == UVC_STATE_STREAMING)
-		queue_work(video->async_wq, &video->pump);
+	if (ret < 0)
+		uvcg_queue_cancel(queue, 0);
 }
 
 static int
 uvc_video_free_requests(struct uvc_video *video)
 {
-	unsigned int i;
-
-	if (video->ureq) {
-		for (i = 0; i < video->uvc_num_requests; ++i) {
-			sg_free_table(&video->ureq[i].sgt);
+	struct uvc_request *ureq, *temp;
 
-			if (video->ureq[i].req) {
-				usb_ep_free_request(video->ep, video->ureq[i].req);
-				video->ureq[i].req = NULL;
-			}
-
-			if (video->ureq[i].req_buffer) {
-				kfree(video->ureq[i].req_buffer);
-				video->ureq[i].req_buffer = NULL;
-			}
-		}
-
-		kfree(video->ureq);
-		video->ureq = NULL;
-	}
+	list_for_each_entry_safe(ureq, temp, &video->ureqs, list)
+		uvc_video_free_request(ureq, video->ep);
 
+	INIT_LIST_HEAD(&video->ureqs);
 	INIT_LIST_HEAD(&video->req_free);
+	INIT_LIST_HEAD(&video->req_ready);
 	video->req_size = 0;
 	return 0;
 }
@@ -322,6 +501,7 @@ uvc_video_free_requests(struct uvc_video *video)
 static int
 uvc_video_alloc_requests(struct uvc_video *video)
 {
+	struct uvc_request *ureq;
 	unsigned int req_size;
 	unsigned int i;
 	int ret = -ENOMEM;
@@ -332,29 +512,33 @@ uvc_video_alloc_requests(struct uvc_video *video)
 		 * max_t(unsigned int, video->ep->maxburst, 1)
 		 * (video->ep->mult);
 
-	video->ureq = kcalloc(video->uvc_num_requests, sizeof(struct uvc_request), GFP_KERNEL);
-	if (video->ureq == NULL)
-		return -ENOMEM;
+	for (i = 0; i < video->uvc_num_requests; i++) {
+		ureq = kzalloc(sizeof(struct uvc_request), GFP_KERNEL);
+		if (ureq == NULL)
+			goto error;
+
+		INIT_LIST_HEAD(&ureq->list);
 
-	for (i = 0; i < video->uvc_num_requests; ++i) {
-		video->ureq[i].req_buffer = kmalloc(req_size, GFP_KERNEL);
-		if (video->ureq[i].req_buffer == NULL)
+		list_add_tail(&ureq->list, &video->ureqs);
+
+		ureq->req_buffer = kmalloc(req_size, GFP_KERNEL);
+		if (ureq->req_buffer == NULL)
 			goto error;
 
-		video->ureq[i].req = usb_ep_alloc_request(video->ep, GFP_KERNEL);
-		if (video->ureq[i].req == NULL)
+		ureq->req = usb_ep_alloc_request(video->ep, GFP_KERNEL);
+		if (ureq->req == NULL)
 			goto error;
 
-		video->ureq[i].req->buf = video->ureq[i].req_buffer;
-		video->ureq[i].req->length = 0;
-		video->ureq[i].req->complete = uvc_video_complete;
-		video->ureq[i].req->context = &video->ureq[i];
-		video->ureq[i].video = video;
-		video->ureq[i].last_buf = NULL;
+		ureq->req->buf = ureq->req_buffer;
+		ureq->req->length = 0;
+		ureq->req->complete = uvc_video_complete;
+		ureq->req->context = ureq;
+		ureq->video = video;
+		ureq->last_buf = NULL;
 
-		list_add_tail(&video->ureq[i].req->list, &video->req_free);
+		list_add_tail(&ureq->req->list, &video->req_free);
 		/* req_size/PAGE_SIZE + 1 for overruns and + 1 for header */
-		sg_alloc_table(&video->ureq[i].sgt,
+		sg_alloc_table(&ureq->sgt,
 			       DIV_ROUND_UP(req_size - UVCG_REQUEST_HEADER_LEN,
 					    PAGE_SIZE) + 2, GFP_KERNEL);
 	}
@@ -387,16 +571,18 @@ static void uvcg_video_pump(struct work_struct *work)
 	struct usb_request *req = NULL;
 	struct uvc_buffer *buf;
 	unsigned long flags;
-	bool buf_done;
-	int ret;
+	int ret = 0;
+
+	while (true) {
+		if (!video->ep->enabled)
+			return;
 
-	while (video->ep->enabled) {
 		/*
-		 * Retrieve the first available USB request, protected by the
-		 * request lock.
+		 * Check is_enabled and retrieve the first available USB
+		 * request, protected by the request lock.
 		 */
 		spin_lock_irqsave(&video->req_lock, flags);
-		if (list_empty(&video->req_free)) {
+		if (!video->is_enabled || list_empty(&video->req_free)) {
 			spin_unlock_irqrestore(&video->req_lock, flags);
 			return;
 		}
@@ -411,19 +597,7 @@ static void uvcg_video_pump(struct work_struct *work)
 		 */
 		spin_lock_irqsave(&queue->irqlock, flags);
 		buf = uvcg_queue_head(queue);
-
-		if (buf != NULL) {
-			video->encode(req, video, buf);
-			buf_done = buf->state == UVC_BUF_STATE_DONE;
-		} else if (!(queue->flags & UVC_QUEUE_DISCONNECTED) && !is_bulk) {
-			/*
-			 * No video buffer available; the queue is still connected and
-			 * we're transferring over ISOC. Queue a 0 length request to
-			 * prevent missed ISOC transfers.
-			 */
-			req->length = 0;
-			buf_done = false;
-		} else {
+		if (!buf) {
 			/*
 			 * Either the queue has been disconnected or no video buffer
 			 * available for bulk transfer. Either way, stop processing
@@ -433,82 +607,140 @@ static void uvcg_video_pump(struct work_struct *work)
 			break;
 		}
 
-		/*
-		 * With USB3 handling more requests at a higher speed, we can't
-		 * afford to generate an interrupt for every request. Decide to
-		 * interrupt:
-		 *
-		 * - When no more requests are available in the free queue, as
-		 *   this may be our last chance to refill the endpoint's
-		 *   request queue.
-		 *
-		 * - When this is request is the last request for the video
-		 *   buffer, as we want to start sending the next video buffer
-		 *   ASAP in case it doesn't get started already in the next
-		 *   iteration of this loop.
-		 *
-		 * - Four times over the length of the requests queue (as
-		 *   indicated by video->uvc_num_requests), as a trade-off
-		 *   between latency and interrupt load.
-		 */
-		if (list_empty(&video->req_free) || buf_done ||
-		    !(video->req_int_count %
-		       DIV_ROUND_UP(video->uvc_num_requests, 4))) {
-			video->req_int_count = 0;
-			req->no_interrupt = 0;
-		} else {
-			req->no_interrupt = 1;
-		}
+		video->encode(req, video, buf);
 
-		/* Queue the USB request */
-		ret = uvcg_video_ep_queue(video, req);
 		spin_unlock_irqrestore(&queue->irqlock, flags);
 
+		spin_lock_irqsave(&video->req_lock, flags);
+		/* For bulk end points we queue from the worker thread
+		 * since we would preferably not want to wait on requests
+		 * to be ready, in the uvcg_video_complete() handler.
+		 * For isoc endpoints we add the request to the ready list
+		 * and only queue it to the endpoint from the complete handler.
+		 */
+		ret = uvcg_video_usb_req_queue(video, req, is_bulk);
+		spin_unlock_irqrestore(&video->req_lock, flags);
+
 		if (ret < 0) {
 			uvcg_queue_cancel(queue, 0);
 			break;
 		}
 
-		/* Endpoint now owns the request */
+		/* The request is owned by  the endpoint / ready list. */
 		req = NULL;
-		video->req_int_count++;
 	}
 
 	if (!req)
 		return;
 
 	spin_lock_irqsave(&video->req_lock, flags);
-	list_add_tail(&req->list, &video->req_free);
+	if (video->is_enabled)
+		list_add_tail(&req->list, &video->req_free);
+	else
+		uvc_video_free_request(req->context, video->ep);
 	spin_unlock_irqrestore(&video->req_lock, flags);
-	return;
 }
 
 /*
- * Enable or disable the video stream.
+ * Disable the video stream
  */
-int uvcg_video_enable(struct uvc_video *video, int enable)
+int
+uvcg_video_disable(struct uvc_video *video)
 {
-	unsigned int i;
-	int ret;
+	unsigned long flags;
+	struct list_head inflight_bufs;
+	struct usb_request *req, *temp;
+	struct uvc_buffer *buf, *btemp;
+	struct uvc_request *ureq, *utemp;
 
 	if (video->ep == NULL) {
 		uvcg_info(&video->uvc->func,
-			  "Video enable failed, device is uninitialized.\n");
+			  "Video disable failed, device is uninitialized.\n");
 		return -ENODEV;
 	}
 
-	if (!enable) {
-		cancel_work_sync(&video->pump);
-		uvcg_queue_cancel(&video->queue, 0);
+	INIT_LIST_HEAD(&inflight_bufs);
+	spin_lock_irqsave(&video->req_lock, flags);
+	video->is_enabled = false;
+
+	/*
+	 * Remove any in-flight buffers from the uvc_requests
+	 * because we want to return them before cancelling the
+	 * queue. This ensures that we aren't stuck waiting for
+	 * all complete callbacks to come through before disabling
+	 * vb2 queue.
+	 */
+	list_for_each_entry(ureq, &video->ureqs, list) {
+		if (ureq->last_buf) {
+			list_add_tail(&ureq->last_buf->queue, &inflight_bufs);
+			ureq->last_buf = NULL;
+		}
+	}
+	spin_unlock_irqrestore(&video->req_lock, flags);
+
+	cancel_work_sync(&video->pump);
+	uvcg_queue_cancel(&video->queue, 0);
+
+	spin_lock_irqsave(&video->req_lock, flags);
+	/*
+	 * Remove all uvc_requests from ureqs with list_del_init
+	 * This lets uvc_video_free_request correctly identify
+	 * if the uvc_request is attached to a list or not when freeing
+	 * memory.
+	 */
+	list_for_each_entry_safe(ureq, utemp, &video->ureqs, list)
+		list_del_init(&ureq->list);
+
+	list_for_each_entry_safe(req, temp, &video->req_free, list) {
+		list_del(&req->list);
+		uvc_video_free_request(req->context, video->ep);
+	}
+
+	list_for_each_entry_safe(req, temp, &video->req_ready, list) {
+		list_del(&req->list);
+		uvc_video_free_request(req->context, video->ep);
+	}
 
-		for (i = 0; i < video->uvc_num_requests; ++i)
-			if (video->ureq && video->ureq[i].req)
-				usb_ep_dequeue(video->ep, video->ureq[i].req);
+	INIT_LIST_HEAD(&video->ureqs);
+	INIT_LIST_HEAD(&video->req_free);
+	INIT_LIST_HEAD(&video->req_ready);
+	video->req_size = 0;
+	spin_unlock_irqrestore(&video->req_lock, flags);
 
-		uvc_video_free_requests(video);
-		uvcg_queue_enable(&video->queue, 0);
-		return 0;
+	/*
+	 * Return all the video buffers before disabling the queue.
+	 */
+	spin_lock_irqsave(&video->queue.irqlock, flags);
+	list_for_each_entry_safe(buf, btemp, &inflight_bufs, queue) {
+		list_del(&buf->queue);
+		uvcg_complete_buffer(&video->queue, buf);
 	}
+	spin_unlock_irqrestore(&video->queue.irqlock, flags);
+
+	uvcg_queue_enable(&video->queue, 0);
+	return 0;
+}
+
+/*
+ * Enable the video stream.
+ */
+int uvcg_video_enable(struct uvc_video *video)
+{
+	int ret;
+
+	if (video->ep == NULL) {
+		uvcg_info(&video->uvc->func,
+			  "Video enable failed, device is uninitialized.\n");
+		return -ENODEV;
+	}
+
+	/*
+	 * Safe to access request related fields without req_lock because
+	 * this is the only thread currently active, and no other
+	 * request handling thread will become active until this function
+	 * returns.
+	 */
+	video->is_enabled = true;
 
 	if ((ret = uvcg_queue_enable(&video->queue, 1)) < 0)
 		return ret;
@@ -525,7 +757,7 @@ int uvcg_video_enable(struct uvc_video *video, int enable)
 
 	video->req_int_count = 0;
 
-	queue_work(video->async_wq, &video->pump);
+	uvc_video_ep_queue_initial_requests(video);
 
 	return ret;
 }
@@ -535,7 +767,10 @@ int uvcg_video_enable(struct uvc_video *video, int enable)
  */
 int uvcg_video_init(struct uvc_video *video, struct uvc_device *uvc)
 {
+	video->is_enabled = false;
+	INIT_LIST_HEAD(&video->ureqs);
 	INIT_LIST_HEAD(&video->req_free);
+	INIT_LIST_HEAD(&video->req_ready);
 	spin_lock_init(&video->req_lock);
 	INIT_WORK(&video->pump, uvcg_video_pump);
 
diff --git a/drivers/usb/gadget/function/uvc_video.h b/drivers/usb/gadget/function/uvc_video.h
index 03adeefa34..8ef6259741 100644
--- a/drivers/usb/gadget/function/uvc_video.h
+++ b/drivers/usb/gadget/function/uvc_video.h
@@ -14,7 +14,8 @@
 
 struct uvc_video;
 
-int uvcg_video_enable(struct uvc_video *video, int enable);
+int uvcg_video_enable(struct uvc_video *video);
+int uvcg_video_disable(struct uvc_video *video);
 
 int uvcg_video_init(struct uvc_video *video, struct uvc_device *uvc);