linux-kernel - [PATCH v2 3/3] usb: gadget: f_sourcesink: Addition of SSP endpoint for ISOC transfers

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <20250828112944.2042343-4-srikanth.chary-chennoju@amd.com>
Date: Thu, 28 Aug 2025 16:59:44 +0530
From: Srikanth Chary Chennoju <srikanth.chary-chennoju@....com>
To: <gregkh@...uxfoundation.org>, <Thinh.Nguyen@...opsys.com>,
	<m.grzeschik@...gutronix.de>, <Chris.Wulff@...mp.com>, <tiwai@...e.de>
CC: <linux-usb@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
	<punnaiah.choudary.kalluri@....com>, Srikanth Chary Chennoju
	<srikanth.chary-chennoju@....com>
Subject: [PATCH v2 3/3] usb: gadget: f_sourcesink: Addition of SSP endpoint for ISOC transfers

This patch is created to support super speed plus endpoint for Isoc
transfers. Now super speed endpoint companion is accompanied by super
speed plus endpoint companion. With this change we could see the Isoc IN
and OUT performance reaching to ~749MB/sec which is 96K per uframe.
The performance numbers are confirmed through Lecroy trace.

Signed-off-by: Srikanth Chary Chennoju <srikanth.chary-chennoju@....com>
---
 drivers/usb/gadget/function/f_sourcesink.c | 23 ++++++++++++++++++++--
 include/uapi/linux/usb/ch9.h               |  2 ++
 2 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/gadget/function/f_sourcesink.c b/drivers/usb/gadget/function/f_sourcesink.c
index a3a69166c343..79efb6295725 100644
--- a/drivers/usb/gadget/function/f_sourcesink.c
+++ b/drivers/usb/gadget/function/f_sourcesink.c
@@ -232,6 +232,12 @@ static struct usb_ss_ep_comp_descriptor ss_iso_source_comp_desc = {
 	.wBytesPerInterval =	cpu_to_le16(1024),
 };
 
+static struct usb_ssp_isoc_ep_comp_descriptor ssp_iso_source_comp_desc = {
+	.bLength =		USB_DT_SSP_ISOC_EP_COMP_SIZE,
+	.bDescriptorType =	USB_DT_SSP_ISOC_ENDPOINT_COMP,
+	.dwBytesPerInterval =	cpu_to_le32(1024),
+};
+
 static struct usb_endpoint_descriptor ss_iso_sink_desc = {
 	.bLength =		USB_DT_ENDPOINT_SIZE,
 	.bDescriptorType =	USB_DT_ENDPOINT,
@@ -250,6 +256,12 @@ static struct usb_ss_ep_comp_descriptor ss_iso_sink_comp_desc = {
 	.wBytesPerInterval =	cpu_to_le16(1024),
 };
 
+static struct usb_ssp_isoc_ep_comp_descriptor ssp_iso_sink_comp_desc = {
+	.bLength =		USB_DT_SSP_ISOC_EP_COMP_SIZE,
+	.bDescriptorType =	USB_DT_SSP_ISOC_ENDPOINT_COMP,
+	.dwBytesPerInterval =	cpu_to_le32(1024),
+};
+
 static struct usb_descriptor_header *ss_source_sink_descs[] = {
 	(struct usb_descriptor_header *) &source_sink_intf_alt0,
 	(struct usb_descriptor_header *) &ss_source_desc,
@@ -264,8 +276,10 @@ static struct usb_descriptor_header *ss_source_sink_descs[] = {
 	(struct usb_descriptor_header *) &ss_sink_comp_desc,
 	(struct usb_descriptor_header *) &ss_iso_source_desc,
 	(struct usb_descriptor_header *) &ss_iso_source_comp_desc,
+	(struct usb_descriptor_header *) &ssp_iso_source_comp_desc,
 	(struct usb_descriptor_header *) &ss_iso_sink_desc,
 	(struct usb_descriptor_header *) &ss_iso_sink_comp_desc,
+	(struct usb_descriptor_header *) &ssp_iso_sink_comp_desc,
 	NULL,
 };
 
@@ -423,7 +437,7 @@ sourcesink_bind(struct usb_configuration *c, struct usb_function *f)
 	 */
 	ss_iso_source_desc.wMaxPacketSize = ss->isoc_maxpacket;
 	ss_iso_source_desc.bInterval = ss->isoc_interval;
-	ss_iso_source_comp_desc.bmAttributes = ss->isoc_mult;
+	ss_iso_source_comp_desc.bmAttributes = USB_DT_SSP_ISOC_COMP | ss->isoc_mult;
 	ss_iso_source_comp_desc.bMaxBurst = ss->isoc_maxburst;
 	ss_iso_source_comp_desc.wBytesPerInterval = ss->isoc_maxpacket *
 		(ss->isoc_mult + 1) * (ss->isoc_maxburst + 1);
@@ -432,12 +446,17 @@ sourcesink_bind(struct usb_configuration *c, struct usb_function *f)
 
 	ss_iso_sink_desc.wMaxPacketSize = ss->isoc_maxpacket;
 	ss_iso_sink_desc.bInterval = ss->isoc_interval;
-	ss_iso_sink_comp_desc.bmAttributes = ss->isoc_mult;
+	ss_iso_sink_comp_desc.bmAttributes = USB_DT_SSP_ISOC_COMP | ss->isoc_mult;
 	ss_iso_sink_comp_desc.bMaxBurst = ss->isoc_maxburst;
 	ss_iso_sink_comp_desc.wBytesPerInterval = ss->isoc_maxpacket *
 		(ss->isoc_mult + 1) * (ss->isoc_maxburst + 1);
 	ss_iso_sink_desc.bEndpointAddress = fs_iso_sink_desc.bEndpointAddress;
 
+	ssp_iso_source_comp_desc.dwBytesPerInterval = ss->isoc_maxpacket *
+	  (ss->isoc_mult + 1) * (ss->isoc_maxburst + 1) * USB_LANE_SPEED_MANTISSA_GEN2_BY_GEN1;
+	ssp_iso_sink_comp_desc.dwBytesPerInterval = ss->isoc_maxpacket *
+	  (ss->isoc_mult + 1) * (ss->isoc_maxburst + 1) * USB_LANE_SPEED_MANTISSA_GEN2_BY_GEN1;
+
 	ret = usb_assign_descriptors(f, fs_source_sink_descs,
 			hs_source_sink_descs, ss_source_sink_descs,
 			ss_source_sink_descs);
diff --git a/include/uapi/linux/usb/ch9.h b/include/uapi/linux/usb/ch9.h
index 8003243a4937..22782c5cb2f3 100644
--- a/include/uapi/linux/usb/ch9.h
+++ b/include/uapi/linux/usb/ch9.h
@@ -702,6 +702,8 @@ struct usb_ssp_isoc_ep_comp_descriptor {
 } __attribute__ ((packed));
 
 #define USB_DT_SSP_ISOC_EP_COMP_SIZE		8
+#define USB_DT_SSP_ISOC_COMP			(1 << 7) /*support for SSP ISOC EP COMP*/
+#define USB_LANE_SPEED_MANTISSA_GEN2_BY_GEN1    2
 
 /*-------------------------------------------------------------------------*/
 
-- 
2.25.1