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usb: Handle different sublink speeds

PATCH Superseded Thinh Nguyen 2 participants 16 messages Jul 26, 2020 – Sep 5, 2020

Subsystems (3)

v4 of 5 Superseded Latest is v5 →

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Thinh Nguyen

author maintainer
#0 lore raw

v4 cover usb: Handle different sublink speeds

A USB super-speed-plus device may operate at different sublink speed and lane count (e.g. gen2x2, gen1x2, or gen2x1). The usb gadget stack needs to be able to handle a couple things:

1) Report the sublink speed attributes the device support
2) Select the sublink speed attribute

This series introduces sublink speed attribute structure to ch9.h to capture the device capability of the gadget. It also introduces a new gadget ops udc_set_num_lanes_and_speed to select a specific sublink speed.

DWC3 needs this support for DWC_usb32 IP. Implement the new changes for DWC3.

Changes in v4:
- Instead of using a single function to parse "maximum-speed" property for speed, gen X, and number of lanes, split those tasks to separate common functions
- Revise DWC3 driver to use those new common functions
- Fix checkpatch warnings for using "unsigned" rather than "unsigned int" and missing identifier name in udc_set_num_lanes_and_speed gadget ops

Changes in v3:
- Remove "num-lanes" and "lane-speed-mantissa-gbps" common properties
- Remove "num-lanes" and "lane-speed-mantissa-gbps" properties validation in dwc3
- Update "maximum-speed" to support variations of SSP Gen X x Y
- Update common function to parse new strings for "maximum-speed"
- Update commit messages for the new changes

Changes in v2:
- Move usb_sublink_speed attribute struct and enum to include/linux/usb/ch9.h
- Use "num-lanes" and "lane-speed-mantissa-gbps" as common properties instead
- Add common functions to get num-lanes and lsm properties
- Fix missing gen1x2 sublink speed attribute check report in dwc3

Thinh Nguyen (12):
usb: ch9: Add sublink speed struct
usb: gadget: composite: Avoid using magic numbers
usb: gadget: Expose sublink speed attributes
usb: gadget: Set max speed for SSP devices
usb: composite: Properly report sublink speed
usb: devicetree: Include USB SSP Gen X x Y
usb: common: Add and update common functions for SSP speeds
usb: dwc3: Initialize lane count and sublink speed
usb: dwc3: gadget: Report sublink speed capability
usb: dwc3: gadget: Implement setting of sublink speed
usb: dwc3: gadget: Track connected lane and sublink speed
usb: dwc3: gadget: Set speed only up to the max supported

 Documentation/devicetree/bindings/usb/generic.txt |  11 +-
 drivers/usb/common/common.c                       |  46 ++++++-
 drivers/usb/dwc3/core.c                           |  29 +++++
 drivers/usb/dwc3/core.h                           |  14 +++
 drivers/usb/dwc3/gadget.c                         | 143 +++++++++++++++++++++-
 drivers/usb/gadget/composite.c                    |  81 ++++++++----
 drivers/usb/gadget/udc/core.c                     |  24 +++-
 include/linux/usb/ch9.h                           |  73 +++++++++++
 include/linux/usb/gadget.h                        |  23 ++++
 9 files changed, 403 insertions(+), 41 deletions(-)

base-commit: a1ff2f6769e39055e973b068070aeea0b3bcd90f

Signature · 1 line
2.11.0
author maintainer
#1 lore raw

PATCH v4 1/12 usb: ch9: Add sublink speed struct

USB 3.2 specification supports dual-lane for super-speed-plus. USB devices may operate at different sublink speeds. To avoid using magic numbers and capture the sublink speed better, introduce the usb_sublink_speed structure and various sublink speed attribute enum.

See SSP BOS descriptor in USB 3.2 specification section 9.6.2.5

---
Changes in v4:
- None
Changes in v3:
- None
Changes in v2:
- Move to include/linux/usb/ch9.h instead of under uapi

 include/linux/usb/ch9.h | 43 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 43 insertions(+)
include/linux/usb/ch9.h +43 -0
index 604c6c514a50..01191649a0ad 100644
@@ -36,6 +36,49 @@
 #include <linux/device.h>
 #include <uapi/linux/usb/ch9.h>
 
+/* USB 3.2 sublink speed attributes */
+
+enum usb_lane_speed_exponent {
+	USB_LSE_BPS = 0,
+	USB_LSE_KBPS = 1,
+	USB_LSE_MBPS = 2,
+	USB_LSE_GBPS = 3,
+};
+
+enum usb_sublink_type {
+	USB_ST_SYMMETRIC_RX = 0,
+	USB_ST_ASYMMETRIC_RX = 1,
+	USB_ST_SYMMETRIC_TX = 2,
+	USB_ST_ASYMMETRIC_TX = 3,
+};
+
+enum usb_link_protocol {
+	USB_LP_SS = 0,
+	USB_LP_SSP = 1,
+};
+
+/**
+ * struct usb_sublink_speed - sublink speed attribute
+ * @id: sublink speed attribute ID (SSID)
+ * @mantissa: lane speed mantissa
+ * @exponent: lane speed exponent
+ * @type: sublink type
+ * @protocol: sublink protocol
+ *
+ * Super-speed-plus supports multiple lanes. Use the sublink speed attributes to
+ * describe the sublink speed.
+ *
+ * See USB 3.2 spec section 9.6.2.6 for super-speed-plus capability for more
+ * information.
+ */
+struct usb_sublink_speed {
+	u8				id;
+	u16				mantissa;
+	enum usb_lane_speed_exponent	exponent;
+	enum usb_sublink_type		type;
+	enum usb_link_protocol		protocol;
+};
+
 /**
  * usb_ep_type_string() - Returns human readable-name of the endpoint type.
  * @ep_type: The endpoint type to return human-readable name for.  If it's not
Signature · 1 line
2.11.0
author maintainer
#2 lore raw

PATCH v4 2/12 usb: gadget: composite: Avoid using magic numbers

In reply to Thinh Nguyen

Magic numbers are difficult to read. Use macros for super-speed-plus BOS descriptor attributes in the composite driver. They're self-documented. So there's no need to provide comments as we did previously for the magic numbers.

---
Changes in v4:
- None
Changes in v3:
- None
Changes in v2:
- None

 drivers/usb/gadget/composite.c | 41 ++++++++++++++++++++---------------------
 1 file changed, 20 insertions(+), 21 deletions(-)
drivers/usb/gadget/composite.c +20 -21
index 05b176c82cc5..0aa4cb49aa53 100644
@@ -13,6 +13,7 @@
 #include <linux/module.h>
 #include <linux/device.h>
 #include <linux/utsname.h>
+#include <linux/bitfield.h>
 
 #include <linux/usb/composite.h>
 #include <linux/usb/otg.h>
@@ -743,32 +744,30 @@ static int bos_desc(struct usb_composite_dev *cdev)
 		ssp_cap->bReserved = 0;
 		ssp_cap->wReserved = 0;
 
-		/* SSAC = 1 (2 attributes) */
-		ssp_cap->bmAttributes = cpu_to_le32(1);
+		ssp_cap->bmAttributes =
+			cpu_to_le32(FIELD_PREP(USB_SSP_SUBLINK_SPEED_ATTRIBS, 1) |
+				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_IDS, 0));
 
-		/* Min RX/TX Lane Count = 1 */
 		ssp_cap->wFunctionalitySupport =
-			cpu_to_le16((1 << 8) | (1 << 12));
+			cpu_to_le16(FIELD_PREP(USB_SSP_MIN_SUBLINK_SPEED_ATTRIBUTE_ID, 0) |
+				    FIELD_PREP(USB_SSP_MIN_RX_LANE_COUNT, 1) |
+				    FIELD_PREP(USB_SSP_MIN_TX_LANE_COUNT, 1));
 
-		/*
-		 * bmSublinkSpeedAttr[0]:
-		 *   ST  = Symmetric, RX
-		 *   LSE =  3 (Gbps)
-		 *   LP  =  1 (SuperSpeedPlus)
-		 *   LSM = 10 (10 Gbps)
-		 */
 		ssp_cap->bmSublinkSpeedAttr[0] =
-			cpu_to_le32((3 << 4) | (1 << 14) | (0xa << 16));
-		/*
-		 * bmSublinkSpeedAttr[1] =
-		 *   ST  = Symmetric, TX
-		 *   LSE =  3 (Gbps)
-		 *   LP  =  1 (SuperSpeedPlus)
-		 *   LSM = 10 (10 Gbps)
-		 */
+			cpu_to_le32(FIELD_PREP(USB_SSP_SUBLINK_SPEED_SSID, 0) |
+				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSE, USB_LSE_GBPS) |
+				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_ST,
+					       USB_ST_SYMMETRIC_RX) |
+				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LP, USB_LP_SSP) |
+				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSM, 10));
+
 		ssp_cap->bmSublinkSpeedAttr[1] =
-			cpu_to_le32((3 << 4) | (1 << 14) |
-				    (0xa << 16) | (1 << 7));
+			cpu_to_le32(FIELD_PREP(USB_SSP_SUBLINK_SPEED_SSID, 0) |
+				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSE, USB_LSE_GBPS) |
+				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_ST,
+					       USB_ST_SYMMETRIC_TX) |
+				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LP, USB_LP_SSP) |
+				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSM, 10));
 	}
 
 	return le16_to_cpu(bos->wTotalLength);
Signature · 1 line
2.11.0
author maintainer
#3 lore raw

PATCH v4 3/12 usb: gadget: Expose sublink speed attributes

In reply to Thinh Nguyen

The USB 3.2 specification supports dual-lane and different transfer rates for super-speed-plus. Devices operating in super-speed-plus can be gen2x1, gen1x2, or gen2x2.

A gadget driver may need to know the gadget's sublink speeds to properly setup its transfer requests and describe its capability in its descriptors. To describe the transfer rate in super-speed-plus fully, let's expose the lane count and sublink speed attributes when operating in super-speed-plus.

---
Changes in v4:
- Change unsigned fields to unsigned int
Changes in v3:
- None
Changes in v2:
- None

 include/linux/usb/gadget.h | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)
include/linux/usb/gadget.h +20 -0
index 52ce1f6b8f83..d25aefaacba0 100644
@@ -339,6 +339,15 @@ struct usb_gadget_ops {
  * @speed: Speed of current connection to USB host.
  * @max_speed: Maximal speed the UDC can handle.  UDC must support this
  *      and all slower speeds.
+ * @num_lanes: Number of lanes in use.
+ * @max_num_lanes: Maximum number of lanes the UDC supports.
+ * @ssac: Sublink speed attribute count. The number of sublink speed
+ *	attributes is ssac + 1.
+ * @sublink_speed: Array of sublink speed attributes the UDC supports. Sublink
+ *	speed attributes are paired, and an RX followed by a TX attribute.
+ * @speed_ssid: Current sublink speed attribute ID in use.
+ * @min_speed_ssid: Sublink speed attribute ID with the minimum speed.
+ * @max_speed_ssid: Sublink speed attribute ID with the maximum speed.
  * @state: the state we are now (attached, suspended, configured, etc)
  * @name: Identifies the controller hardware type.  Used in diagnostics
  *	and sometimes configuration.
@@ -406,6 +415,17 @@ struct usb_gadget {
 	struct list_head		ep_list;	/* of usb_ep */
 	enum usb_device_speed		speed;
 	enum usb_device_speed		max_speed;
+
+	/* SSP only */
+	unsigned int			num_lanes;
+	unsigned int			max_num_lanes;
+	unsigned int			ssac;
+#define USB_GADGET_MAX_SSAC 3
+	struct usb_sublink_speed	sublink_speed[USB_GADGET_MAX_SSAC + 1];
+	unsigned int			speed_ssid;
+	unsigned int			min_speed_ssid;
+	unsigned int			max_speed_ssid;
+
 	enum usb_device_state		state;
 	const char			*name;
 	struct device			dev;
Signature · 1 line
2.11.0
author maintainer
#4 lore raw

PATCH v4 4/12 usb: gadget: Set max speed for SSP devices

In reply to Thinh Nguyen

A super-speed-plus device may operate at different sublink speeds (e.g. gen2x2, gen1x2, or gen2x1). If the USB device supports different sublink speeds at super-speed-plus, set the device to operate at the maximum number of lanes and sublink speed possible. Introduce gadget ops udc_set_num_lanes_and_speed to set the lane count and sublink speed for super-speed-plus capable devices.

---
Changes in v4:
- Add identifier name for usb_gadget in gadget ops (*udc_set_num_lanes_and_speed) to avoid checkpatch warning
Changes in v3:
- None
Changes in v2:
- None

 drivers/usb/gadget/udc/core.c | 24 +++++++++++++++++++-----
 include/linux/usb/gadget.h    |  3 +++
 2 files changed, 22 insertions(+), 5 deletions(-)
drivers/usb/gadget/udc/core.c +19 -5
index 4f82bcd31fd3..e5f569dc9ee0 100644
@@ -1114,12 +1114,26 @@ static inline void usb_gadget_udc_stop(struct usb_udc *udc)
 static inline void usb_gadget_udc_set_speed(struct usb_udc *udc,
 					    enum usb_device_speed speed)
 {
-	if (udc->gadget->ops->udc_set_speed) {
-		enum usb_device_speed s;
+	struct usb_gadget *gadget = udc->gadget;
+	enum usb_device_speed s;
 
-		s = min(speed, udc->gadget->max_speed);
-		udc->gadget->ops->udc_set_speed(udc->gadget, s);
-	}
+	if (speed == USB_SPEED_UNKNOWN)
+		s = gadget->max_speed;
+	else
+		s = min(speed, gadget->max_speed);
+
+	/*
+	 * If the UDC supports super-speed-plus and different sublink speeds,
+	 * then set the gadget to the max possible sublink speed for
+	 * super-speed-plus symmetric lanes.
+	 */
+	if (s == USB_SPEED_SUPER_PLUS &&
+	    gadget->ops->udc_set_num_lanes_and_speed)
+		gadget->ops->udc_set_num_lanes_and_speed(gadget,
+							 gadget->max_num_lanes,
+							 gadget->max_speed_ssid);
+	else if (gadget->ops->udc_set_speed)
+		gadget->ops->udc_set_speed(gadget, s);
 }
 
 /**
include/linux/usb/gadget.h +3 -0
index d25aefaacba0..3bbd8d7a80ad 100644
@@ -323,6 +323,9 @@ struct usb_gadget_ops {
 			struct usb_gadget_driver *);
 	int	(*udc_stop)(struct usb_gadget *);
 	void	(*udc_set_speed)(struct usb_gadget *, enum usb_device_speed);
+	void	(*udc_set_num_lanes_and_speed)(struct usb_gadget *gadget,
+					       unsigned int num_lanes,
+					       unsigned int ssid);
 	struct usb_ep *(*match_ep)(struct usb_gadget *,
 			struct usb_endpoint_descriptor *,
 			struct usb_ss_ep_comp_descriptor *);
Signature · 1 line
2.11.0
author maintainer
#5 lore raw

PATCH v4 5/12 usb: composite: Properly report sublink speed

In reply to Thinh Nguyen

Use the max sublink speed attributes reported in the gadget structure to write to the super-speed-plus BOS descriptor if available.

---
Changes in v4:
- None
Changes in v3:
- None
Changes in v2:
- None

 drivers/usb/gadget/composite.c | 76 +++++++++++++++++++++++++++++-------------
 1 file changed, 52 insertions(+), 24 deletions(-)
drivers/usb/gadget/composite.c +52 -24
index 0aa4cb49aa53..2d0b7af4b08f 100644
@@ -729,45 +729,73 @@ static int bos_desc(struct usb_composite_dev *cdev)
 	/* The SuperSpeedPlus USB Device Capability descriptor */
 	if (gadget_is_superspeed_plus(cdev->gadget)) {
 		struct usb_ssp_cap_descriptor *ssp_cap;
+		unsigned int ssac = 1;
+		unsigned int ssic = 0;
+		unsigned int min_ssid = 0;
+		int i;
+
+		if (cdev->gadget->ssac) {
+			ssac = cdev->gadget->ssac;
+
+			/*
+			 * Paired RX and TX sublink speed attributes share
+			 * the same SSID.
+			 */
+			ssic = (ssac + 1) / 2 - 1;
+			min_ssid = cdev->gadget->min_speed_ssid;
+		}
 
 		ssp_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 		bos->bNumDeviceCaps++;
 
-		/*
-		 * Report typical values.
-		 */
-
-		le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SSP_CAP_SIZE(1));
-		ssp_cap->bLength = USB_DT_USB_SSP_CAP_SIZE(1);
+		le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SSP_CAP_SIZE(ssac));
+		ssp_cap->bLength = USB_DT_USB_SSP_CAP_SIZE(ssac);
 		ssp_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 		ssp_cap->bDevCapabilityType = USB_SSP_CAP_TYPE;
 		ssp_cap->bReserved = 0;
 		ssp_cap->wReserved = 0;
 
 		ssp_cap->bmAttributes =
-			cpu_to_le32(FIELD_PREP(USB_SSP_SUBLINK_SPEED_ATTRIBS, 1) |
-				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_IDS, 0));
+			cpu_to_le32(FIELD_PREP(USB_SSP_SUBLINK_SPEED_ATTRIBS, ssac) |
+				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_IDS, ssic));
 
 		ssp_cap->wFunctionalitySupport =
-			cpu_to_le16(FIELD_PREP(USB_SSP_MIN_SUBLINK_SPEED_ATTRIBUTE_ID, 0) |
+			cpu_to_le16(FIELD_PREP(USB_SSP_MIN_SUBLINK_SPEED_ATTRIBUTE_ID, min_ssid) |
 				    FIELD_PREP(USB_SSP_MIN_RX_LANE_COUNT, 1) |
 				    FIELD_PREP(USB_SSP_MIN_TX_LANE_COUNT, 1));
 
-		ssp_cap->bmSublinkSpeedAttr[0] =
-			cpu_to_le32(FIELD_PREP(USB_SSP_SUBLINK_SPEED_SSID, 0) |
-				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSE, USB_LSE_GBPS) |
-				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_ST,
-					       USB_ST_SYMMETRIC_RX) |
-				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LP, USB_LP_SSP) |
-				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSM, 10));
-
-		ssp_cap->bmSublinkSpeedAttr[1] =
-			cpu_to_le32(FIELD_PREP(USB_SSP_SUBLINK_SPEED_SSID, 0) |
-				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSE, USB_LSE_GBPS) |
-				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_ST,
-					       USB_ST_SYMMETRIC_TX) |
-				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LP, USB_LP_SSP) |
-				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSM, 10));
+		/*
+		 * If the sublink speed attributes are not specified, then the
+		 * default will be a pair symmetric RX/TX sublink speed
+		 * attributes of 10 Gbps.
+		 */
+		for (i = 0; i < ssac + 1; i++) {
+			struct usb_sublink_speed default_ssa;
+			struct usb_sublink_speed *ptr;
+
+			if (cdev->gadget->ssac) {
+				ptr = &cdev->gadget->sublink_speed[i];
+			} else {
+				default_ssa.id = i / 2;
+				default_ssa.protocol = USB_LP_SSP;
+				default_ssa.exponent = USB_LSE_GBPS;
+				default_ssa.mantissa = 10;
+
+				if (i % 2)
+					default_ssa.type = USB_ST_SYMMETRIC_TX;
+				else
+					default_ssa.type = USB_ST_SYMMETRIC_RX;
+
+				ptr = &default_ssa;
+			}
+
+			ssp_cap->bmSublinkSpeedAttr[i] =
+				cpu_to_le32(FIELD_PREP(USB_SSP_SUBLINK_SPEED_SSID, ptr->id) |
+					    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSE, ptr->exponent) |
+					    FIELD_PREP(USB_SSP_SUBLINK_SPEED_ST, ptr->type) |
+					    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LP, ptr->protocol) |
+					    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSM, ptr->mantissa));
+		}
 	}
 
 	return le16_to_cpu(bos->wTotalLength);
Signature · 1 line
2.11.0
author maintainer
#6 lore raw

PATCH v4 6/12 usb: devicetree: Include USB SSP Gen X x Y

In reply to Thinh Nguyen

According to the USB 3.2 spec, a super-speed-plus device can operate at gen2x2, gen2x1, or gen1x2. If the USB controller device supports multiple lanes at different transfer rates, the user can specify the HW capability via these new speed strings:

"super-speed-plus-gen2x2"
"super-speed-plus-gen2x1"
"super-speed-plus-gen1x2"

If the argument is simply "super-speed-plus", USB controllers should default to their maximum transfer rate and number of lanes.

---
Changes in v4:
- None
Changes in v3:
- Use "maximum-speed" to include both the num-lane and transfer rate for SSP
- Remove "num-lanes" and "lane-speed-mantissa-gbps" properties Changes in v2:
- Make "num-lanes" and "lane-speed-mantissa-gbps" common USB properties

 Documentation/devicetree/bindings/usb/generic.txt | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)
Documentation/devicetree/bindings/usb/generic.txt +7 -4
index ba472e7aefc9..8541b9571f2f 100644
@@ -3,10 +3,13 @@ Generic USB Properties
 Optional properties:
  - maximum-speed: tells USB controllers we want to work up to a certain
 			speed. Valid arguments are "super-speed-plus",
-			"super-speed", "high-speed", "full-speed" and
-			"low-speed". In case this isn't passed via DT, USB
-			controllers should default to their maximum HW
-			capability.
+			"super-speed-plus-gen2x2", "super-speed-plus-gen2x1",
+			"super-speed-plus-gen1x2", "super-speed", "high-speed",
+			"full-speed" and "low-speed". In case this isn't passed
+			via DT, USB controllers should default to their maximum
+			HW capability. Similarly, if the argument is
+			"super-speed-plus", USB controllers should default to
+			their maximum transfer rate and number of lanes.
  - dr_mode: tells Dual-Role USB controllers that we want to work on a
 			particular mode. Valid arguments are "host",
 			"peripheral" and "otg". In case this attribute isn't
Signature · 1 line
2.11.0
maintainer Reviewed-by on v4 6/12
#7 lore raw

Re: [PATCH v4 06/12] usb: devicetree: Include USB SSP Gen X x Y

Quoted 22 lines · Thinh Nguyen

According to the USB 3.2 spec, a super-speed-plus device can operate at gen2x2, gen2x1, or gen1x2. If the USB controller device supports multiple lanes at different transfer rates, the user can specify the HW capability via these new speed strings:

"super-speed-plus-gen2x2"
"super-speed-plus-gen2x1"
"super-speed-plus-gen1x2"

If the argument is simply "super-speed-plus", USB controllers should default to their maximum transfer rate and number of lanes.

---
Changes in v4:
- None
Changes in v3:
- Use "maximum-speed" to include both the num-lane and transfer rate for SSP
- Remove "num-lanes" and "lane-speed-mantissa-gbps" properties Changes in v2:
- Make "num-lanes" and "lane-speed-mantissa-gbps" common USB properties

Quoted 3 lines
 Documentation/devicetree/bindings/usb/generic.txt | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)
author maintainer
#8 lore raw

Re: [PATCH v4 06/12] usb: devicetree: Include USB SSP Gen X x Y

Quoted 23 lines · Rob Herring
Quoted 22 lines · Thinh Nguyen

According to the USB 3.2 spec, a super-speed-plus device can operate at gen2x2, gen2x1, or gen1x2. If the USB controller device supports multiple lanes at different transfer rates, the user can specify the HW capability via these new speed strings:

"super-speed-plus-gen2x2"
"super-speed-plus-gen2x1"
"super-speed-plus-gen1x2"

If the argument is simply "super-speed-plus", USB controllers should default to their maximum transfer rate and number of lanes.

---
Changes in v4:
- None
Changes in v3:
- Use "maximum-speed" to include both the num-lane and transfer rate for SSP
- Remove "num-lanes" and "lane-speed-mantissa-gbps" properties Changes in v2:
- Make "num-lanes" and "lane-speed-mantissa-gbps" common USB properties

Quoted 4 lines
Quoted 3 lines
 Documentation/devicetree/bindings/usb/generic.txt | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

Thanks!
Thinh

author maintainer
#9 lore raw

PATCH v4 7/12 usb: common: Add and update common functions for SSP speeds

In reply to Thinh Nguyen

The USB "maximum-speed" property now can take these new strings for super-speed-plus:

"super-speed-plus-gen2x2"
"super-speed-plus-gen2x1"
"super-speed-plus-gen1x2"

As a result, let's do the follow:
* Update usb_get_maximum_speed() to parse these new speed strings
* Add 2 new common functions to get the Gen number and number of lanes

---
Changes in v4:
- Create 2 functions to get the SSP gen and number of lanes from "maximum-speed" property
- Update usb_get_maximum_speed() to check new SSP strings with genXxY
- Update commit message and subject title to reflect the new changes Changes in v3:
- Add new function to parse "maximum-speed" for lanes and transfer rate
- Remove separate functions getting num_lanes and transfer rate properties Changes in v2:
- New commit

 drivers/usb/common/common.c | 46 ++++++++++++++++++++++++++++++++++++++++++++-
 include/linux/usb/ch9.h     | 30 +++++++++++++++++++++++++++++
 2 files changed, 75 insertions(+), 1 deletion(-)
drivers/usb/common/common.c +45 -1
index 1433260d99b4..b3b3972d5be7 100644
@@ -86,12 +86,56 @@ enum usb_device_speed usb_get_maximum_speed(struct device *dev)
 	if (ret < 0)
 		return USB_SPEED_UNKNOWN;
 
-	ret = match_string(speed_names, ARRAY_SIZE(speed_names), maximum_speed);
+	if (strncmp("super-speed-plus-gen2x2", maximum_speed, 23) == 0 ||
+	    strncmp("super-speed-plus-gen2x1", maximum_speed, 23) == 0 ||
+	    strncmp("super-speed-plus-gen1x2", maximum_speed, 23) == 0)
+		return USB_SPEED_SUPER_PLUS;
 
+	ret = match_string(speed_names, ARRAY_SIZE(speed_names), maximum_speed);
 	return (ret < 0) ? USB_SPEED_UNKNOWN : ret;
 }
 EXPORT_SYMBOL_GPL(usb_get_maximum_speed);
 
+u8 usb_get_ssp_num_lanes(struct device *dev)
+{
+	const char *maximum_speed;
+	int ret;
+
+	ret = device_property_read_string(dev, "maximum-speed", &maximum_speed);
+	if (ret < 0)
+		return 0;
+
+	if (strncmp("super-speed-plus-gen2x1", maximum_speed, 23) == 0)
+		return 1;
+
+	if (strncmp("super-speed-plus-gen2x2", maximum_speed, 23) == 0 ||
+	    strncmp("super-speed-plus-gen1x2", maximum_speed, 23) == 0)
+		return 2;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(usb_get_ssp_num_lanes);
+
+enum usb_phy_gen usb_get_ssp_phy_gen(struct device *dev)
+{
+	const char *maximum_speed;
+	int ret;
+
+	ret = device_property_read_string(dev, "maximum-speed", &maximum_speed);
+	if (ret < 0)
+		return USB_PHY_GEN_UNKNOWN;
+
+	if (strncmp("super-speed-plus-gen1x2", maximum_speed, 23) == 0)
+		return USB_PHY_GEN_1;
+
+	if (strncmp("super-speed-plus-gen2x2", maximum_speed, 23) == 0 ||
+	    strncmp("super-speed-plus-gen2x1", maximum_speed, 23) == 0)
+		return USB_PHY_GEN_2;
+
+	return USB_PHY_GEN_UNKNOWN;
+}
+EXPORT_SYMBOL_GPL(usb_get_ssp_phy_gen);
+
 const char *usb_state_string(enum usb_device_state state)
 {
 	static const char *const names[] = {
include/linux/usb/ch9.h +30 -0
index 01191649a0ad..bd13d27551e5 100644
@@ -57,6 +57,13 @@ enum usb_link_protocol {
 	USB_LP_SSP = 1,
 };
 
+/* USB phy signaling rate generation */
+enum usb_phy_gen {
+	USB_PHY_GEN_UNKNOWN,
+	USB_PHY_GEN_1,
+	USB_PHY_GEN_2,
+};
+
 /**
  * struct usb_sublink_speed - sublink speed attribute
  * @id: sublink speed attribute ID (SSID)
@@ -105,6 +112,29 @@ extern const char *usb_speed_string(enum usb_device_speed speed);
  */
 extern enum usb_device_speed usb_get_maximum_speed(struct device *dev);
 
+/**
+ * usb_get_ssp_num_lanes - Get requested number of lanes for a given
+ * super-speed-plus capable USB controller.
+ * @dev: Pointer to the given USB controller device
+ *
+ * If the string from "maximum-speed" property is super-speed-plus-genXxY where
+ * 'Y' is the number of lanes, then this function returns 1 for single lane and
+ * 2 for dual-lane base on 'Y'. If the number of lanes is not specified, then it
+ * returns 0.
+ */
+extern u8 usb_get_ssp_num_lanes(struct device *dev);
+
+/**
+ * usb_get_ssp_phy_gen - Get requested phy signaling rate generation for a given
+ * super-speed-plus capable USB controller.
+ * @dev: Pointer to the given USB controller device
+ *
+ * If the string from "maximum-speed" property is super-speed-plus-genXxY where
+ * 'X' is the Gen number, then this function returns the corresponding enum
+ * usb_phy_gen base on 'X'.
+ */
+extern enum usb_phy_gen usb_get_ssp_phy_gen(struct device *dev);
+
 /**
  * usb_state_string - Returns human readable name for the state.
  * @state: The state to return a human-readable name for. If it's not
Signature · 1 line
2.11.0
author maintainer
#10 lore raw

PATCH v4 8/12 usb: dwc3: Initialize lane count and sublink speed

In reply to Thinh Nguyen

DWC_usb32 supports dual-lane operating at different sublink speeds. Initialize and validate the maximum number of lanes and speed the controller supports in the maximum_speed property.

Currently the controller has no visibility into the HW parameter to determine the maximum number of lanes the HW supports. If the number of lanes is not specified, then set the default to 2 for DWC_usb32 and 1 for DWC_usb31 for SSP.

---
Changes in v4:
- Use new common funtions to get SSP Gen and number of lanes Changes in v3:
- Use new common function to get maximum-speed
- Remove num_lanes and lsm validation since they are no longer separate properties
- Replace dwc->maxmum_lsm field with dwc->maximum_ssp_rate for gen1/gen2 Changes in v2:
- Use common functions to get num_lanes and lsm properties

 drivers/usb/dwc3/core.c | 29 +++++++++++++++++++++++++++++
 drivers/usb/dwc3/core.h |  6 ++++++
 2 files changed, 35 insertions(+)
drivers/usb/dwc3/core.c +29 -0
index b2ea96d2db04..d3604c74cac5 100644
@@ -1268,6 +1268,8 @@ static void dwc3_get_properties(struct dwc3 *dwc)
 	hird_threshold = 12;
 
 	dwc->maximum_speed = usb_get_maximum_speed(dev);
+	dwc->maximum_phy_gen = usb_get_ssp_phy_gen(dev);
+	dwc->maximum_num_lanes = usb_get_ssp_num_lanes(dev);
 	dwc->dr_mode = usb_get_dr_mode(dev);
 	dwc->hsphy_mode = of_usb_get_phy_mode(dev->of_node);
 
@@ -1436,6 +1438,33 @@ static void dwc3_check_params(struct dwc3 *dwc)
 		}
 		break;
 	}
+
+	/*
+	 * Currently the controller does not have visibility into the HW
+	 * parameter to determine the maximum number of lanes the HW
+	 * supports. If the number of lanes is not specified in the
+	 * device property, then set the default to 2 for DWC_usb32 and
+	 * 1 for DWC_usb31 for super-speed-plus.
+	 */
+	if (dwc->maximum_speed == USB_SPEED_SUPER_PLUS) {
+		if (DWC3_IP_IS(DWC32)) {
+			if (dwc->maximum_phy_gen == USB_PHY_GEN_UNKNOWN)
+				dwc->maximum_phy_gen = USB_PHY_GEN_2;
+
+			if (!dwc->maximum_num_lanes)
+				dwc->maximum_num_lanes = 2;
+
+		} else if (DWC3_IP_IS(DWC31)) {
+			if (dwc->maximum_num_lanes > 1)
+				dev_warn(dev, "UDC doesn't support multi-lanes\n");
+
+			dwc->maximum_phy_gen = USB_PHY_GEN_2;
+			dwc->maximum_num_lanes = 1;
+		}
+	} else {
+		dwc->maximum_phy_gen = USB_PHY_GEN_UNKNOWN;
+		dwc->maximum_num_lanes = 0;
+	}
 }
 
 static int dwc3_probe(struct platform_device *pdev)
drivers/usb/dwc3/core.h +6 -0
index 2f04b3e42bf1..3bbfbeaa67d8 100644
@@ -958,6 +958,8 @@ struct dwc3_scratchpad_array {
  * @nr_scratch: number of scratch buffers
  * @u1u2: only used on revisions <1.83a for workaround
  * @maximum_speed: maximum speed requested (mainly for testing purposes)
+ * @maximum_phy_gen: maximum phy signaling rate
+ * @maximum_num_lanes: maximum number of lanes
  * @ip: controller's ID
  * @revision: controller's version of an IP
  * @version_type: VERSIONTYPE register contents, a sub release of a revision
@@ -988,6 +990,7 @@ struct dwc3_scratchpad_array {
  * @ep0state: state of endpoint zero
  * @link_state: link state
  * @speed: device speed (super, high, full, low)
+ * @num_lanes: number of connected lanes
  * @hwparams: copy of hwparams registers
  * @root: debugfs root folder pointer
  * @regset: debugfs pointer to regdump file
@@ -1119,6 +1122,8 @@ struct dwc3 {
 	u32			nr_scratch;
 	u32			u1u2;
 	u32			maximum_speed;
+	enum usb_phy_gen	maximum_phy_gen;
+	u8			maximum_num_lanes;
 
 	u32			ip;
 
@@ -1184,6 +1189,7 @@ struct dwc3 {
 	u8			u1pel;
 
 	u8			speed;
+	u8			num_lanes;
 
 	u8			num_eps;
 
Signature · 1 line
2.11.0
author maintainer
#11 lore raw

PATCH v4 9/12 usb: dwc3: gadget: Report sublink speed capability

In reply to Thinh Nguyen

Report the sublink speed attributes to the usb_gadget structure based on the HW capability from the device maximum_speed property.

Only DWC_usb32 supports 2 sublink speeds if it can operate with 2 lanes. (i.e. at SSP, it can operate as gen1x2)

Note: the SSID DWC3_SSP_SSID_GEN2 and DWC3_SSP_SSID_GEN1 are arbitrary. There's no standard according to the USB 3.2 spec as long as they are unique and within 0-15.

---
Changes in v4:
- None
Changes in v3:
- Update commit with updated field name
- No longer use DWC3_LSM_5/10_GBPS macros
Changes in v2:
- Fix missing check for gen1x2 when writing to sublink speed attributes
- Minor fix in commit message (first commit sentence ended with comma)

 drivers/usb/dwc3/core.h   |  4 ++++
 drivers/usb/dwc3/gadget.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 53 insertions(+)
drivers/usb/dwc3/core.h +4 -0
index 3bbfbeaa67d8..0ec675327014 100644
@@ -40,6 +40,10 @@
 #define DWC3_XHCI_RESOURCES_NUM	2
 #define DWC3_ISOC_MAX_RETRIES	5
 
+/* Sublink Speed Attribute ID */
+#define DWC3_SSP_SSID_GEN2	2
+#define DWC3_SSP_SSID_GEN1	1
+
 #define DWC3_SCRATCHBUF_SIZE	4096	/* each buffer is assumed to be 4KiB */
 #define DWC3_EVENT_BUFFERS_SIZE	4096
 #define DWC3_EVENT_TYPE_MASK	0xfe
drivers/usb/dwc3/gadget.c +49 -0

55 lines not on this page · raw message

Signature · 1 line
2.11.0
author maintainer
#12 lore raw

PATCH v4 10/12 usb: dwc3: gadget: Implement setting of sublink speed

In reply to Thinh Nguyen

Implement gadget ops udc_set_num_lanes_and_speed. This allows the gadget/core driver to select number of lanes to use and the sublink speed the controller supports.

---
Changes in v4:
- None
Changes in v3:
- None
Changes in v2:
- None

 drivers/usb/dwc3/core.h   |  2 ++
 drivers/usb/dwc3/gadget.c | 64 ++++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 65 insertions(+), 1 deletion(-)
drivers/usb/dwc3/core.h +2 -0
index 0ec675327014..9466c4c36963 100644
@@ -385,6 +385,8 @@
 #define DWC3_GUCTL2_RST_ACTBITLATER		BIT(14)
 
 /* Device Configuration Register */
+#define DWC3_DCFG_NUMLANES(n)	(((n) & 0x3) << 30) /* DWC_usb32 only */
+
 #define DWC3_DCFG_DEVADDR(addr)	((addr) << 3)
 #define DWC3_DCFG_DEVADDR_MASK	DWC3_DCFG_DEVADDR(0x7f)
 
drivers/usb/dwc3/gadget.c +63 -1

82 lines not on this page · raw message

Signature · 1 line
2.11.0
author maintainer
#13 lore raw

PATCH v4 11/12 usb: dwc3: gadget: Track connected lane and sublink speed

In reply to Thinh Nguyen

Track the number of lanes connected in gadget->num_lanes and track the current sublink speed attribute ID for super-speed-plus operations.

Note: if the device is running in gen1x2, set the gadget->speed to USB_SPEED_SUPER_PLUS.

---
Changes in v4:
- None
Changes in v3:
- None
Changes in v2:
- None

 drivers/usb/dwc3/core.h   |  2 ++
 drivers/usb/dwc3/gadget.c | 21 ++++++++++++++++++++-
 2 files changed, 22 insertions(+), 1 deletion(-)
drivers/usb/dwc3/core.h +2 -0
index 9466c4c36963..4a70b1e4d2a7 100644
@@ -460,6 +460,8 @@
 #define DWC3_DEVTEN_USBRSTEN		BIT(1)
 #define DWC3_DEVTEN_DISCONNEVTEN	BIT(0)
 
+#define DWC3_DSTS_CONNLANES(n)		(((n) >> 30) & 0x3) /* DWC_usb32 only */
+
 /* Device Status Register */
 #define DWC3_DSTS_DCNRD			BIT(29)
 
drivers/usb/dwc3/gadget.c +20 -1
index b7da4e1c81aa..05defaf0f745 100644
@@ -2328,6 +2328,10 @@ static void dwc3_gadget_set_speed(struct usb_gadget *g,
 				reg |= DWC3_DCFG_SUPERSPEED_PLUS;
 		}
 	}
+
+	if (DWC3_IP_IS(DWC32) && speed < USB_SPEED_SUPER_PLUS)
+		reg &= ~DWC3_DCFG_NUMLANES(~0);
+
 	dwc3_writel(dwc->regs, DWC3_DCFG, reg);
 
 	spin_unlock_irqrestore(&dwc->lock, flags);
@@ -3199,12 +3203,19 @@ static void dwc3_gadget_conndone_interrupt(struct dwc3 *dwc)
 	struct dwc3_ep		*dep;
 	int			ret;
 	u32			reg;
+	u8			lanes = 1;
 	u8			speed;
 
 	reg = dwc3_readl(dwc->regs, DWC3_DSTS);
 	speed = reg & DWC3_DSTS_CONNECTSPD;
 	dwc->speed = speed;
 
+	if (DWC3_IP_IS(DWC32))
+		lanes = DWC3_DSTS_CONNLANES(reg) + 1;
+
+	dwc->gadget.num_lanes = lanes;
+	dwc->gadget.speed_ssid = 0;
+
 	/*
 	 * RAMClkSel is reset to 0 after USB reset, so it must be reprogrammed
 	 * each time on Connect Done.
@@ -3219,6 +3230,7 @@ static void dwc3_gadget_conndone_interrupt(struct dwc3 *dwc)
 		dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
 		dwc->gadget.ep0->maxpacket = 512;
 		dwc->gadget.speed = USB_SPEED_SUPER_PLUS;
+		dwc->gadget.speed_ssid = DWC3_SSP_SSID_GEN2;
 		break;
 	case DWC3_DSTS_SUPERSPEED:
 		/*
@@ -3239,7 +3251,13 @@ static void dwc3_gadget_conndone_interrupt(struct dwc3 *dwc)
 
 		dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
 		dwc->gadget.ep0->maxpacket = 512;
-		dwc->gadget.speed = USB_SPEED_SUPER;
+
+		if (lanes > 1) {
+			dwc->gadget.speed = USB_SPEED_SUPER_PLUS;
+			dwc->gadget.speed_ssid = DWC3_SSP_SSID_GEN1;
+		} else {
+			dwc->gadget.speed = USB_SPEED_SUPER;
+		}
 		break;
 	case DWC3_DSTS_HIGHSPEED:
 		dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(64);
@@ -3720,6 +3738,7 @@ int dwc3_gadget_init(struct dwc3 *dwc)
 	dwc->gadget.sg_supported	= true;
 	dwc->gadget.name		= "dwc3-gadget";
 	dwc->gadget.lpm_capable		= true;
+	dwc->gadget.num_lanes		= 1;
 
 	/*
 	 * FIXME We might be setting max_speed to <SUPER, however versions
Signature · 1 line
2.11.0
author maintainer
#14 lore raw

PATCH v4 12/12 usb: dwc3: gadget: Set speed only up to the max supported

In reply to Thinh Nguyen

The setting of device speed should be limited by the device's maximum_speed. This patch adds a check and prevent the driver from attempting to configure higher than the maximum_speed.

---
Changes in v4:
- None
Changes in v3:
- None
Changes in v2:
- None

 drivers/usb/dwc3/gadget.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)
drivers/usb/dwc3/gadget.c +8 -3
index 05defaf0f745..f62a9519287a 100644
@@ -2276,6 +2276,7 @@ static void dwc3_gadget_set_speed(struct usb_gadget *g,
 				  enum usb_device_speed speed)
 {
 	struct dwc3		*dwc = gadget_to_dwc(g);
+	enum usb_device_speed	selected_speed = speed;
 	unsigned long		flags;
 	u32			reg;
 
@@ -2300,7 +2301,10 @@ static void dwc3_gadget_set_speed(struct usb_gadget *g,
 	    !dwc->dis_metastability_quirk) {
 		reg |= DWC3_DCFG_SUPERSPEED;
 	} else {
-		switch (speed) {
+		if (speed > dwc->maximum_speed)
+			selected_speed = dwc->maximum_speed;
+
+		switch (selected_speed) {
 		case USB_SPEED_LOW:
 			reg |= DWC3_DCFG_LOWSPEED;
 			break;
@@ -2320,7 +2324,8 @@ static void dwc3_gadget_set_speed(struct usb_gadget *g,
 				reg |= DWC3_DCFG_SUPERSPEED_PLUS;
 			break;
 		default:
-			dev_err(dwc->dev, "invalid speed (%d)\n", speed);
+			dev_err(dwc->dev, "invalid speed (%d)\n",
+				selected_speed);
 
 			if (DWC3_IP_IS(DWC3))
 				reg |= DWC3_DCFG_SUPERSPEED;
@@ -2329,7 +2334,7 @@ static void dwc3_gadget_set_speed(struct usb_gadget *g,
 		}
 	}
 
-	if (DWC3_IP_IS(DWC32) && speed < USB_SPEED_SUPER_PLUS)
+	if (DWC3_IP_IS(DWC32) && selected_speed < USB_SPEED_SUPER_PLUS)
 		reg &= ~DWC3_DCFG_NUMLANES(~0);
 
 	dwc3_writel(dwc->regs, DWC3_DCFG, reg);
Signature · 1 line
2.11.0
author maintainer
#15 lore raw
In reply to Thinh Nguyen

Hi all,

Quoted 61 lines · Thinh Nguyen

A USB super-speed-plus device may operate at different sublink speed and lane count (e.g. gen2x2, gen1x2, or gen2x1). The usb gadget stack needs to be able to handle a couple things:

1) Report the sublink speed attributes the device support
2) Select the sublink speed attribute

This series introduces sublink speed attribute structure to ch9.h to capture the device capability of the gadget. It also introduces a new gadget ops udc_set_num_lanes_and_speed to select a specific sublink speed.

DWC3 needs this support for DWC_usb32 IP. Implement the new changes for DWC3.

Changes in v4:
- Instead of using a single function to parse "maximum-speed" property for speed, gen X, and number of lanes, split those tasks to separate common functions
- Revise DWC3 driver to use those new common functions
- Fix checkpatch warnings for using "unsigned" rather than "unsigned int" and missing identifier name in udc_set_num_lanes_and_speed gadget ops

Changes in v3:
- Remove "num-lanes" and "lane-speed-mantissa-gbps" common properties
- Remove "num-lanes" and "lane-speed-mantissa-gbps" properties validation in dwc3
- Update "maximum-speed" to support variations of SSP Gen X x Y
- Update common function to parse new strings for "maximum-speed"
- Update commit messages for the new changes

Changes in v2:
- Move usb_sublink_speed attribute struct and enum to include/linux/usb/ch9.h
- Use "num-lanes" and "lane-speed-mantissa-gbps" as common properties instead
- Add common functions to get num-lanes and lsm properties
- Fix missing gen1x2 sublink speed attribute check report in dwc3

Thinh Nguyen (12):
usb: ch9: Add sublink speed struct
usb: gadget: composite: Avoid using magic numbers
usb: gadget: Expose sublink speed attributes
usb: gadget: Set max speed for SSP devices
usb: composite: Properly report sublink speed
usb: devicetree: Include USB SSP Gen X x Y
usb: common: Add and update common functions for SSP speeds
usb: dwc3: Initialize lane count and sublink speed
usb: dwc3: gadget: Report sublink speed capability
usb: dwc3: gadget: Implement setting of sublink speed
usb: dwc3: gadget: Track connected lane and sublink speed
usb: dwc3: gadget: Set speed only up to the max supported

 Documentation/devicetree/bindings/usb/generic.txt |  11 +-
 drivers/usb/common/common.c                       |  46 ++++++-
 drivers/usb/dwc3/core.c                           |  29 +++++
 drivers/usb/dwc3/core.h                           |  14 +++
 drivers/usb/dwc3/gadget.c                         | 143 +++++++++++++++++++++-
 drivers/usb/gadget/composite.c                    |  81 ++++++++----
 drivers/usb/gadget/udc/core.c                     |  24 +++-
 include/linux/usb/ch9.h                           |  73 +++++++++++
 include/linux/usb/gadget.h                        |  23 ++++
 9 files changed, 403 insertions(+), 41 deletions(-)
Quoted 1 line

base-commit: a1ff2f6769e39055e973b068070aeea0b3bcd90f

Gentle ping...

Let me know if you have any concern for any of the patch in this series.

Thanks,
Thinh