[PATCH 00/11] usb: Handle different sublink speeds

[PATCH 00/11] usb: Handle different sublink speeds

[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.


Thinh Nguyen (11):
  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: dwc3: Introduce num-lanes and lsm
  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/dwc3.txt |   9 ++
 drivers/usb/dwc3/core.c                        |  64 ++++++++++++
 drivers/usb/dwc3/core.h                        |  18 ++++
 drivers/usb/dwc3/gadget.c                      | 135 ++++++++++++++++++++++++-
 drivers/usb/gadget/composite.c                 |  81 ++++++++++-----
 drivers/usb/gadget/udc/core.c                  |  24 ++++-
 include/linux/usb/gadget.h                     |  23 +++++
 include/uapi/linux/usb/ch9.h                   |  42 ++++++++
 8 files changed, 360 insertions(+), 36 deletions(-)

-- 
2.11.0

[PATCH 01/11] usb: ch9: Add sublink speed struct

[Thinh Nguyen]

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

Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
---
 include/uapi/linux/usb/ch9.h | 42 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)

diff --git a/include/uapi/linux/usb/ch9.h b/include/uapi/linux/usb/ch9.h
index 2b623f36af6b..d4fd403a3664 100644
--- a/include/uapi/linux/usb/ch9.h
+++ b/include/uapi/linux/usb/ch9.h
@@ -1145,6 +1145,48 @@ enum usb_device_speed {
 	USB_SPEED_SUPER_PLUS,			/* usb 3.1 */
 };
 
+/* 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
+ * @sublink 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;
+};
 
 enum usb_device_state {
 	/* NOTATTACHED isn't in the USB spec, and this state acts
-- 
2.11.0

[PATCH 02/11] usb: gadget: composite: Avoid using magic numbers

[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.

Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
---
 drivers/usb/gadget/composite.c | 41 ++++++++++++++++++++---------------------
 1 file changed, 20 insertions(+), 21 deletions(-)

diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index 5c1eb96a5c57..a231ae382ac3 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -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);
-- 
2.11.0

[PATCH 03/11] usb: gadget: Expose sublink speed attributes

[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.

Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
---
 include/linux/usb/gadget.h | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h
index 6a178177e4c9..2ab929eed928 100644
--- a/include/linux/usb/gadget.h
+++ b/include/linux/usb/gadget.h
@@ -338,6 +338,15 @@ 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.
@@ -405,6 +414,17 @@ 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			num_lanes;
+	unsigned			max_num_lanes;
+	unsigned			ssac;
+#define USB_GADGET_MAX_SSAC 3
+	struct usb_sublink_speed	sublink_speed[USB_GADGET_MAX_SSAC + 1];
+	unsigned			speed_ssid;
+	unsigned			min_speed_ssid;
+	unsigned			max_speed_ssid;
+
 	enum usb_device_state		state;
 	const char			*name;
 	struct device			dev;
-- 
2.11.0

[PATCH 04/11] usb: gadget: Set max speed for SSP devices

[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.

Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
---
 drivers/usb/gadget/udc/core.c | 24 +++++++++++++++++++-----
 include/linux/usb/gadget.h    |  3 +++
 2 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c
index 2e28dde8376f..1e916b3943fe 100644
--- a/drivers/usb/gadget/udc/core.c
+++ b/drivers/usb/gadget/udc/core.c
@@ -1112,12 +1112,26 @@ 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);
 }
 
 /**
diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h
index 2ab929eed928..ec4ed17e7bf5 100644
--- a/include/linux/usb/gadget.h
+++ b/include/linux/usb/gadget.h
@@ -322,6 +322,9 @@ 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 *,
+					       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 *);
-- 
2.11.0

[PATCH 05/11] usb: composite: Properly report sublink speed

[Thinh Nguyen]

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

Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
---
 drivers/usb/gadget/composite.c | 76 +++++++++++++++++++++++++++++-------------
 1 file changed, 52 insertions(+), 24 deletions(-)

diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index a231ae382ac3..d9fb29a72f94 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -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);
-- 
2.11.0

[PATCH 06/11] usb: devicetree: dwc3: Introduce num-lanes and lsm

[Thinh Nguyen]

Introduce num-lanes and lane-speed-mantissa-gbps for devices operating
in super-speed-plus. DWC_usb32 IP supports multiple lanes and can
operate in different sublink speeds. Currently the device controller
does not have the information of the phy's number of lanes supported. As
a result, the user can specify them through these properties if they are
different than the default setting.

Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
---
 Documentation/devicetree/bindings/usb/dwc3.txt | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt b/Documentation/devicetree/bindings/usb/dwc3.txt
index d03edf9d3935..4eba0615562f 100644
--- a/Documentation/devicetree/bindings/usb/dwc3.txt
+++ b/Documentation/devicetree/bindings/usb/dwc3.txt
@@ -86,6 +86,15 @@ Optional properties:
  - snps,quirk-frame-length-adjustment: Value for GFLADJ_30MHZ field of GFLADJ
 	register for post-silicon frame length adjustment when the
 	fladj_30mhz_sdbnd signal is invalid or incorrect.
+ - snps,num-lanes: set to specify the number of lanes to use. Valid inputs are
+			1 or 2. Apply if the maximum-speed is super-speed-plus
+			only. Default value is 2 for DWC_usb32. For DWC_usb31,
+			it is always 1 at super-speed-plus.
+ - snps,lane-speed-mantissa-gbps: set to specify the symmetric lane speed
+			mantissa in Gbps. Valid inputs are 5 or 10. Apply if
+			the maximum-speed is super-speed-plus only. Default
+			value is 10. For DWC_usb31, it's always 10 at
+			super-speed-plus.
  - snps,rx-thr-num-pkt-prd: periodic ESS RX packet threshold count - host mode
 			only. Set this and rx-max-burst-prd to a valid,
 			non-zero value 1-16 (DWC_usb31 programming guide
-- 
2.11.0

[PATCH 07/11] usb: dwc3: Initialize lane count and sublink speed

[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 captured from the dwc3 device properties.

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

Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
---
 drivers/usb/dwc3/core.c | 64 +++++++++++++++++++++++++++++++++++++++++++++++++
 drivers/usb/dwc3/core.h | 10 ++++++++
 2 files changed, 74 insertions(+)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 25c686a752b0..dcc76705862f 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -1299,6 +1299,10 @@ static void dwc3_get_properties(struct dwc3 *dwc)
 				"snps,usb3_lpm_capable");
 	dwc->usb2_lpm_disable = device_property_read_bool(dev,
 				"snps,usb2-lpm-disable");
+	device_property_read_u8(dev, "snps,num-lanes",
+				&dwc->maximum_num_lanes);
+	device_property_read_u8(dev, "snps,lane-speed-mantissa-gbps",
+				&dwc->maximum_lsm);
 	device_property_read_u8(dev, "snps,rx-thr-num-pkt-prd",
 				&rx_thr_num_pkt_prd);
 	device_property_read_u8(dev, "snps,rx-max-burst-prd",
@@ -1426,6 +1430,66 @@ static void dwc3_check_params(struct dwc3 *dwc)
 
 		break;
 	}
+
+	/*
+	 * If it's not DWC_usb32 IP or speed is less than SSP, no need to
+	 * validate the number of lanes or lane speed mantissa.
+	 *
+	 * Currently the controller does not have visibility into the HW
+	 * parameter to determine the maximum number of lanes the phy 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 if the device
+	 * is capable of super-speed-plus.
+	 */
+	if (!DWC3_IP_IS(DWC32) ||
+	    dwc->maximum_speed < USB_SPEED_SUPER_PLUS) {
+		if (dwc->maximum_lsm || dwc->maximum_num_lanes)
+			dev_warn(dev, "Ignore num_lanes and LSM properties\n");
+
+		if (DWC3_IP_IS(DWC31) &&
+		    dwc->maximum_speed == USB_SPEED_SUPER_PLUS) {
+			dwc->maximum_lsm = DWC3_LSM_10_GBPS;
+			dwc->maximum_num_lanes = 1;
+		} else {
+			dwc->maximum_lsm = DWC3_LSM_UNSPECIFIED;
+			dwc->maximum_num_lanes = 0;
+		}
+
+		return;
+	}
+
+	switch (dwc->maximum_lsm) {
+	case DWC3_LSM_10_GBPS:
+	case DWC3_LSM_5_GBPS:
+		break;
+	default:
+		dev_err(dev, "Invalid LSM (%dGbps)\n", dwc->maximum_lsm);
+		fallthrough;
+	case DWC3_LSM_UNSPECIFIED:
+		dwc->maximum_lsm = DWC3_LSM_10_GBPS;
+		break;
+	}
+
+	switch (dwc->maximum_num_lanes) {
+	case 2:
+		break;
+	case 1:
+		if (dwc->maximum_lsm == DWC3_LSM_5_GBPS) {
+			dev_err(dev, "Invalid num_lanes (%d) and LSM (%dGbps) for %s\n",
+				dwc->maximum_num_lanes,
+				dwc->maximum_lsm,
+				usb_speed_string(dwc->maximum_speed));
+			dwc->maximum_lsm = DWC3_LSM_10_GBPS;
+		}
+		break;
+	default:
+		dev_err(dev, "Invalid number of lanes (%d)\n",
+			dwc->maximum_num_lanes);
+		fallthrough;
+	case 0:
+		dwc->maximum_num_lanes = 2;
+		break;
+	}
 }
 
 static int dwc3_probe(struct platform_device *pdev)
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 013f42a2b5dc..33cfd7f4a7e0 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -40,6 +40,10 @@
 #define DWC3_XHCI_RESOURCES_NUM	2
 #define DWC3_ISOC_MAX_RETRIES	5
 
+#define DWC3_LSM_UNSPECIFIED	0
+#define DWC3_LSM_5_GBPS		5
+#define DWC3_LSM_10_GBPS	10
+
 #define DWC3_SCRATCHBUF_SIZE	4096	/* each buffer is assumed to be 4KiB */
 #define DWC3_EVENT_BUFFERS_SIZE	4096
 #define DWC3_EVENT_TYPE_MASK	0xfe
@@ -958,6 +962,8 @@ 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_lsm: maximum lane speed mantissa in Gbps
+ * @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 +994,7 @@ 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 +1126,8 @@ struct dwc3 {
 	u32			nr_scratch;
 	u32			u1u2;
 	u32			maximum_speed;
+	u8			maximum_lsm;
+	u8			maximum_num_lanes;
 
 	u32			ip;
 
@@ -1184,6 +1193,7 @@ struct dwc3 {
 	u8			u1pel;
 
 	u8			speed;
+	u8			num_lanes;
 
 	u8			num_eps;
 
-- 
2.11.0

[PATCH 08/11] usb: dwc3: gadget: Report sublink speed capability

[Thinh Nguyen]

Report the sublink speed attributes to the usb_gadget structure based on
the dwc3 device capability maximum_lsm and maximum_num_lanes,

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.

Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
---
 drivers/usb/dwc3/core.h   |  4 ++++
 drivers/usb/dwc3/gadget.c | 41 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 45 insertions(+)

diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 33cfd7f4a7e0..e346ae12e69e 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -44,6 +44,10 @@
 #define DWC3_LSM_5_GBPS		5
 #define DWC3_LSM_10_GBPS	10
 
+/* 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
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 80c3ef134e41..1ca57af23994 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -3662,6 +3662,47 @@ int dwc3_gadget_init(struct dwc3 *dwc)
 				dwc->revision);
 
 	dwc->gadget.max_speed		= dwc->maximum_speed;
+	dwc->gadget.max_num_lanes	= dwc->maximum_num_lanes;
+
+	if (dwc->maximum_speed == USB_SPEED_SUPER_PLUS) {
+		struct usb_sublink_speed *ssa;
+		int i;
+
+		/*
+		 * Multiple sublink speeds are only available to DWC_usb32
+		 * devices that can operate at gen2x2 max.
+		 */
+		if (dwc->maximum_lsm == DWC3_LSM_10_GBPS &&
+		    dwc->maximum_num_lanes == 2) {
+			dwc->gadget.ssac = 3;
+			dwc->gadget.min_speed_ssid = DWC3_SSP_SSID_GEN1;
+			dwc->gadget.max_speed_ssid = DWC3_SSP_SSID_GEN2;
+		} else {
+			dwc->gadget.ssac = 1;
+			dwc->gadget.min_speed_ssid = DWC3_SSP_SSID_GEN2;
+			dwc->gadget.max_speed_ssid = DWC3_SSP_SSID_GEN2;
+		}
+
+		for (i = 0; i < dwc->gadget.ssac + 1; i++) {
+			ssa = &dwc->gadget.sublink_speed[i];
+
+			if (i > 1) {
+				ssa->id = DWC3_SSP_SSID_GEN1;
+				ssa->mantissa = DWC3_LSM_5_GBPS;
+			} else {
+				ssa->id = DWC3_SSP_SSID_GEN2;
+				ssa->mantissa = DWC3_LSM_10_GBPS;
+			}
+
+			if (i % 2)
+				ssa->type = USB_ST_SYMMETRIC_TX;
+			else
+				ssa->type = USB_ST_SYMMETRIC_RX;
+
+			ssa->exponent = USB_LSE_GBPS;
+			ssa->protocol = USB_LP_SSP;
+		}
+	}
 
 	/*
 	 * REVISIT: Here we should clear all pending IRQs to be
-- 
2.11.0

[PATCH 09/11] usb: dwc3: gadget: Implement setting of sublink speed

[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.

Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
---
 drivers/usb/dwc3/core.h   |  2 ++
 drivers/usb/dwc3/gadget.c | 64 ++++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 65 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index e346ae12e69e..92ab65a46771 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -389,6 +389,8 @@
 #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)
 
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 1ca57af23994..01bdd51f6b47 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2311,6 +2311,62 @@ static void dwc3_gadget_set_speed(struct usb_gadget *g,
 	spin_unlock_irqrestore(&dwc->lock, flags);
 }
 
+static void dwc3_gadget_set_num_lanes_and_speed(struct usb_gadget *g,
+						unsigned int num_lanes,
+						unsigned int ssid)
+{
+	struct dwc3			*dwc = gadget_to_dwc(g);
+	struct usb_sublink_speed	*ssa = NULL;
+	unsigned int			lanes;
+	unsigned long			flags;
+	u32				reg;
+	int				i;
+
+	spin_lock_irqsave(&dwc->lock, flags);
+	if (dwc->maximum_speed < USB_SPEED_SUPER_PLUS)
+		goto done;
+
+	for (i = 0; i < g->ssac + 1; i++) {
+		if (g->sublink_speed[i].id == ssid) {
+			ssa = &g->sublink_speed[i];
+			break;
+		}
+	}
+
+	if (!ssa) {
+		dev_err(dwc->dev, "SSID not found (%d)\n", ssid);
+		goto done;
+	}
+
+	reg = dwc3_readl(dwc->regs, DWC3_DCFG);
+	reg &= ~DWC3_DCFG_SPEED_MASK;
+
+	switch (ssa->mantissa) {
+	case DWC3_LSM_5_GBPS:
+		reg |= DWC3_DCFG_SUPERSPEED;
+		break;
+	case DWC3_LSM_10_GBPS:
+		reg |= DWC3_DCFG_SUPERSPEED_PLUS;
+		break;
+	default:
+		dev_err(dwc->dev, "invalid lane speed mantissa (%d)\n",
+			ssa->mantissa);
+		goto done;
+	}
+
+	/* Lane configuration is only available to DWC_usb32 */
+	if (DWC3_IP_IS(DWC32)) {
+		lanes = clamp_t(unsigned int, num_lanes, 1,
+				dwc->maximum_num_lanes);
+		reg &= ~DWC3_DCFG_NUMLANES(~0);
+		reg |= DWC3_DCFG_NUMLANES(lanes - 1);
+	}
+
+	dwc3_writel(dwc->regs, DWC3_DCFG, reg);
+done:
+	spin_unlock_irqrestore(&dwc->lock, flags);
+}
+
 static const struct usb_gadget_ops dwc3_gadget_ops = {
 	.get_frame		= dwc3_gadget_get_frame,
 	.wakeup			= dwc3_gadget_wakeup,
@@ -2319,6 +2375,7 @@ static const struct usb_gadget_ops dwc3_gadget_ops = {
 	.udc_start		= dwc3_gadget_start,
 	.udc_stop		= dwc3_gadget_stop,
 	.udc_set_speed		= dwc3_gadget_set_speed,
+	.udc_set_num_lanes_and_speed = dwc3_gadget_set_num_lanes_and_speed,
 	.get_config_params	= dwc3_gadget_config_params,
 };
 
@@ -3719,7 +3776,12 @@ int dwc3_gadget_init(struct dwc3 *dwc)
 		goto err4;
 	}
 
-	dwc3_gadget_set_speed(&dwc->gadget, dwc->maximum_speed);
+	if (DWC3_IP_IS(DWC32) && dwc->maximum_speed == USB_SPEED_SUPER_PLUS)
+		dwc3_gadget_set_num_lanes_and_speed(&dwc->gadget,
+						    dwc->maximum_num_lanes,
+						    dwc->gadget.max_speed_ssid);
+	else
+		dwc3_gadget_set_speed(&dwc->gadget, dwc->maximum_speed);
 
 	return 0;
 
-- 
2.11.0

[PATCH 10/11] usb: dwc3: gadget: Track connected lane and sublink speed

[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.

Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
---
 drivers/usb/dwc3/core.h   |  2 ++
 drivers/usb/dwc3/gadget.c | 21 ++++++++++++++++++++-
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 92ab65a46771..63178549428d 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -464,6 +464,8 @@
 #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)
 
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 01bdd51f6b47..87a69a096b57 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2306,6 +2306,10 @@ 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);
@@ -3175,12 +3179,19 @@ 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.
@@ -3195,6 +3206,7 @@ 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:
 		/*
@@ -3215,7 +3227,13 @@ 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);
@@ -3696,6 +3714,7 @@ 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
-- 
2.11.0

[PATCH 11/11] usb: dwc3: gadget: Set speed only up to the max supported

[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.

Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
---
 drivers/usb/dwc3/gadget.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 87a69a096b57..155251d67b4d 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2254,6 +2254,7 @@ 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;
 
@@ -2278,7 +2279,10 @@ 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;
@@ -2298,7 +2302,8 @@ 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;
@@ -2307,7 +2312,7 @@ 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);
-- 
2.11.0

Re: [PATCH 01/11] usb: ch9: Add sublink speed struct

[Greg Kroah-Hartman]

On Thu, Jul 16, 2020 at 02:58:36PM -0700, Thinh Nguyen wrote:
> 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
> 
> Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
> ---
>  include/uapi/linux/usb/ch9.h | 42 ++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 42 insertions(+)
> 
> diff --git a/include/uapi/linux/usb/ch9.h b/include/uapi/linux/usb/ch9.h
> index 2b623f36af6b..d4fd403a3664 100644
> --- a/include/uapi/linux/usb/ch9.h
> +++ b/include/uapi/linux/usb/ch9.h
> @@ -1145,6 +1145,48 @@ enum usb_device_speed {
>  	USB_SPEED_SUPER_PLUS,			/* usb 3.1 */
>  };
>  
> +/* 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
> + * @sublink 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;

You have to use the proper data types for crossing the user/kernel
boundry here.  That would be __u8 and __u16, right?

> +	enum usb_lane_speed_exponent	exponent;
> +	enum usb_sublink_type		type;
> +	enum usb_link_protocol		protocol;

Are you _sure_ that an enum is the correct size for these fields?  How
can you guarantee this?  We do not use enums in this way for any other
field in this file for a reason...

And did you look at the layout of this structure to verify it actually
matches what is on the wire with USB?  I think you need to add a packed
attribute to guarantee it.

thanks,

greg k-h


> +};
>  
>  enum usb_device_state {
>  	/* NOTATTACHED isn't in the USB spec, and this state acts
> -- 
> 2.11.0
> 

Re: [PATCH 01/11] usb: ch9: Add sublink speed struct

[Thinh Nguyen]

Greg Kroah-Hartman wrote:
> On Thu, Jul 16, 2020 at 02:58:36PM -0700, Thinh Nguyen wrote:
>> 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
>>
>> Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
>> ---
>>   include/uapi/linux/usb/ch9.h | 42 ++++++++++++++++++++++++++++++++++++++++++
>>   1 file changed, 42 insertions(+)
>>
>> diff --git a/include/uapi/linux/usb/ch9.h b/include/uapi/linux/usb/ch9.h
>> index 2b623f36af6b..d4fd403a3664 100644
>> --- a/include/uapi/linux/usb/ch9.h
>> +++ b/include/uapi/linux/usb/ch9.h
>> @@ -1145,6 +1145,48 @@ enum usb_device_speed {
>>   	USB_SPEED_SUPER_PLUS,			/* usb 3.1 */
>>   };
>>   
>> +/* 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
>> + * @sublink 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;
> You have to use the proper data types for crossing the user/kernel
> boundry here.  That would be __u8 and __u16, right?
>
>> +	enum usb_lane_speed_exponent	exponent;
>> +	enum usb_sublink_type		type;
>> +	enum usb_link_protocol		protocol;
> Are you _sure_ that an enum is the correct size for these fields?  How
> can you guarantee this?  We do not use enums in this way for any other
> field in this file for a reason...
>
> And did you look at the layout of this structure to verify it actually
> matches what is on the wire with USB?  I think you need to add a packed
> attribute to guarantee it.

This struct is not intended to be packed to be sent over the bus. It's a 
simple struct for host and gadget driver use only. I intended to use 
enum to make it more clear not to be used that way. From your question, 
it's obviously not clear.

Otherwise, it may look something like this:
struct usb_sublink_speed {
         __u8    ssid:4;
         __u8    lse:2;
         __u8    st:2;
         __u8    rsvd:6;
         __u8    lp:2;
         __le16  lsm;
} __attribute__((packed));

Let me know how you'd like to handle it.

Thanks,
Thinh

Re: [PATCH 01/11] usb: ch9: Add sublink speed struct

[Greg Kroah-Hartman]

On Fri, Jul 17, 2020 at 07:06:10AM +0000, Thinh Nguyen wrote:
> Greg Kroah-Hartman wrote:
> > On Thu, Jul 16, 2020 at 02:58:36PM -0700, Thinh Nguyen wrote:
> >> 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
> >>
> >> Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
> >> ---
> >>   include/uapi/linux/usb/ch9.h | 42 ++++++++++++++++++++++++++++++++++++++++++
> >>   1 file changed, 42 insertions(+)
> >>
> >> diff --git a/include/uapi/linux/usb/ch9.h b/include/uapi/linux/usb/ch9.h
> >> index 2b623f36af6b..d4fd403a3664 100644
> >> --- a/include/uapi/linux/usb/ch9.h
> >> +++ b/include/uapi/linux/usb/ch9.h
> >> @@ -1145,6 +1145,48 @@ enum usb_device_speed {
> >>   	USB_SPEED_SUPER_PLUS,			/* usb 3.1 */
> >>   };
> >>   
> >> +/* 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
> >> + * @sublink 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;
> > You have to use the proper data types for crossing the user/kernel
> > boundry here.  That would be __u8 and __u16, right?
> >
> >> +	enum usb_lane_speed_exponent	exponent;
> >> +	enum usb_sublink_type		type;
> >> +	enum usb_link_protocol		protocol;
> > Are you _sure_ that an enum is the correct size for these fields?  How
> > can you guarantee this?  We do not use enums in this way for any other
> > field in this file for a reason...
> >
> > And did you look at the layout of this structure to verify it actually
> > matches what is on the wire with USB?  I think you need to add a packed
> > attribute to guarantee it.
> 
> This struct is not intended to be packed to be sent over the bus. It's a 
> simple struct for host and gadget driver use only. I intended to use 
> enum to make it more clear not to be used that way. From your question, 
> it's obviously not clear.

Then why are you putting it in this file?  This file is only for things
that are described in the USB spec that need to cross the user/kernel
boundry.

> Otherwise, it may look something like this:
> struct usb_sublink_speed {
>          __u8    ssid:4;
>          __u8    lse:2;
>          __u8    st:2;
>          __u8    rsvd:6;
>          __u8    lp:2;

Are you sure those bit fields will work on big-endian systems?

>          __le16  lsm;
> } __attribute__((packed));

Do you need to read this from a device?

thanks,

greg k-h

Re: [PATCH 01/11] usb: ch9: Add sublink speed struct

[Thinh Nguyen]

Greg Kroah-Hartman wrote:
> On Fri, Jul 17, 2020 at 07:06:10AM +0000, Thinh Nguyen wrote:
>> Greg Kroah-Hartman wrote:
>>> On Thu, Jul 16, 2020 at 02:58:36PM -0700, Thinh Nguyen wrote:
>>>> 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
>>>>
>>>> Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
>>>> ---
>>>>    include/uapi/linux/usb/ch9.h | 42 ++++++++++++++++++++++++++++++++++++++++++
>>>>    1 file changed, 42 insertions(+)
>>>>
>>>> diff --git a/include/uapi/linux/usb/ch9.h b/include/uapi/linux/usb/ch9.h
>>>> index 2b623f36af6b..d4fd403a3664 100644
>>>> --- a/include/uapi/linux/usb/ch9.h
>>>> +++ b/include/uapi/linux/usb/ch9.h
>>>> @@ -1145,6 +1145,48 @@ enum usb_device_speed {
>>>>    	USB_SPEED_SUPER_PLUS,			/* usb 3.1 */
>>>>    };
>>>>    
>>>> +/* 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
>>>> + * @sublink 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;
>>> You have to use the proper data types for crossing the user/kernel
>>> boundry here.  That would be __u8 and __u16, right?
>>>
>>>> +	enum usb_lane_speed_exponent	exponent;
>>>> +	enum usb_sublink_type		type;
>>>> +	enum usb_link_protocol		protocol;
>>> Are you _sure_ that an enum is the correct size for these fields?  How
>>> can you guarantee this?  We do not use enums in this way for any other
>>> field in this file for a reason...
>>>
>>> And did you look at the layout of this structure to verify it actually
>>> matches what is on the wire with USB?  I think you need to add a packed
>>> attribute to guarantee it.
>> This struct is not intended to be packed to be sent over the bus. It's a
>> simple struct for host and gadget driver use only. I intended to use
>> enum to make it more clear not to be used that way. From your question,
>> it's obviously not clear.
> Then why are you putting it in this file?  This file is only for things
> that are described in the USB spec that need to cross the user/kernel
> boundry.

Ok, it seemed to fit here. I'll place it under /include/linux/usb.h then?

>
>> Otherwise, it may look something like this:
>> struct usb_sublink_speed {
>>           __u8    ssid:4;
>>           __u8    lse:2;
>>           __u8    st:2;
>>           __u8    rsvd:6;
>>           __u8    lp:2;
> Are you sure those bit fields will work on big-endian systems?

No. Because of the way the bitfields are placed, it's a path to 
unnecessary headache/bugs with boundary and endianness checks. That's 
why I decided to go with the other solution.

Thanks,
Thinh

Re: [PATCH 01/11] usb: ch9: Add sublink speed struct

[Greg Kroah-Hartman]

On Fri, Jul 17, 2020 at 07:47:03AM +0000, Thinh Nguyen wrote:
> Greg Kroah-Hartman wrote:
> > On Fri, Jul 17, 2020 at 07:06:10AM +0000, Thinh Nguyen wrote:
> >> Greg Kroah-Hartman wrote:
> >>> On Thu, Jul 16, 2020 at 02:58:36PM -0700, Thinh Nguyen wrote:
> >>>> 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
> >>>>
> >>>> Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
> >>>> ---
> >>>>    include/uapi/linux/usb/ch9.h | 42 ++++++++++++++++++++++++++++++++++++++++++
> >>>>    1 file changed, 42 insertions(+)
> >>>>
> >>>> diff --git a/include/uapi/linux/usb/ch9.h b/include/uapi/linux/usb/ch9.h
> >>>> index 2b623f36af6b..d4fd403a3664 100644
> >>>> --- a/include/uapi/linux/usb/ch9.h
> >>>> +++ b/include/uapi/linux/usb/ch9.h
> >>>> @@ -1145,6 +1145,48 @@ enum usb_device_speed {
> >>>>    	USB_SPEED_SUPER_PLUS,			/* usb 3.1 */
> >>>>    };
> >>>>    
> >>>> +/* 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
> >>>> + * @sublink 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;
> >>> You have to use the proper data types for crossing the user/kernel
> >>> boundry here.  That would be __u8 and __u16, right?
> >>>
> >>>> +	enum usb_lane_speed_exponent	exponent;
> >>>> +	enum usb_sublink_type		type;
> >>>> +	enum usb_link_protocol		protocol;
> >>> Are you _sure_ that an enum is the correct size for these fields?  How
> >>> can you guarantee this?  We do not use enums in this way for any other
> >>> field in this file for a reason...
> >>>
> >>> And did you look at the layout of this structure to verify it actually
> >>> matches what is on the wire with USB?  I think you need to add a packed
> >>> attribute to guarantee it.
> >> This struct is not intended to be packed to be sent over the bus. It's a
> >> simple struct for host and gadget driver use only. I intended to use
> >> enum to make it more clear not to be used that way. From your question,
> >> it's obviously not clear.
> > Then why are you putting it in this file?  This file is only for things
> > that are described in the USB spec that need to cross the user/kernel
> > boundry.
> 
> Ok, it seemed to fit here. I'll place it under /include/linux/usb.h then?

include/linux/usb/ch9.h perhaps?

> >> Otherwise, it may look something like this:
> >> struct usb_sublink_speed {
> >>           __u8    ssid:4;
> >>           __u8    lse:2;
> >>           __u8    st:2;
> >>           __u8    rsvd:6;
> >>           __u8    lp:2;
> > Are you sure those bit fields will work on big-endian systems?
> 
> No. Because of the way the bitfields are placed, it's a path to 
> unnecessary headache/bugs with boundary and endianness checks. That's 
> why I decided to go with the other solution.

That's good, but again, this is a uapi file, not a "normal" include file
in the kernel, you have to be careful about this.

greg k-h

Re: [PATCH 01/11] usb: ch9: Add sublink speed struct

[Thinh Nguyen]

Greg Kroah-Hartman wrote:
> On Fri, Jul 17, 2020 at 07:47:03AM +0000, Thinh Nguyen wrote:
>> Greg Kroah-Hartman wrote:
>>> On Fri, Jul 17, 2020 at 07:06:10AM +0000, Thinh Nguyen wrote:
>>>> Greg Kroah-Hartman wrote:
>>>>> On Thu, Jul 16, 2020 at 02:58:36PM -0700, Thinh Nguyen wrote:
>>>>>> 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
>>>>>>
>>>>>> Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
>>>>>> ---
>>>>>>     include/uapi/linux/usb/ch9.h | 42 ++++++++++++++++++++++++++++++++++++++++++
>>>>>>     1 file changed, 42 insertions(+)
>>>>>>
>>>>>> diff --git a/include/uapi/linux/usb/ch9.h b/include/uapi/linux/usb/ch9.h
>>>>>> index 2b623f36af6b..d4fd403a3664 100644
>>>>>> --- a/include/uapi/linux/usb/ch9.h
>>>>>> +++ b/include/uapi/linux/usb/ch9.h
>>>>>> @@ -1145,6 +1145,48 @@ enum usb_device_speed {
>>>>>>     	USB_SPEED_SUPER_PLUS,			/* usb 3.1 */
>>>>>>     };
>>>>>>     
>>>>>> +/* 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
>>>>>> + * @sublink 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;
>>>>> You have to use the proper data types for crossing the user/kernel
>>>>> boundry here.  That would be __u8 and __u16, right?
>>>>>
>>>>>> +	enum usb_lane_speed_exponent	exponent;
>>>>>> +	enum usb_sublink_type		type;
>>>>>> +	enum usb_link_protocol		protocol;
>>>>> Are you _sure_ that an enum is the correct size for these fields?  How
>>>>> can you guarantee this?  We do not use enums in this way for any other
>>>>> field in this file for a reason...
>>>>>
>>>>> And did you look at the layout of this structure to verify it actually
>>>>> matches what is on the wire with USB?  I think you need to add a packed
>>>>> attribute to guarantee it.
>>>> This struct is not intended to be packed to be sent over the bus. It's a
>>>> simple struct for host and gadget driver use only. I intended to use
>>>> enum to make it more clear not to be used that way. From your question,
>>>> it's obviously not clear.
>>> Then why are you putting it in this file?  This file is only for things
>>> that are described in the USB spec that need to cross the user/kernel
>>> boundry.
>> Ok, it seemed to fit here. I'll place it under /include/linux/usb.h then?
> include/linux/usb/ch9.h perhaps?

Sure. I'll place it there.

>>>> Otherwise, it may look something like this:
>>>> struct usb_sublink_speed {
>>>>            __u8    ssid:4;
>>>>            __u8    lse:2;
>>>>            __u8    st:2;
>>>>            __u8    rsvd:6;
>>>>            __u8    lp:2;
>>> Are you sure those bit fields will work on big-endian systems?
>> No. Because of the way the bitfields are placed, it's a path to
>> unnecessary headache/bugs with boundary and endianness checks. That's
>> why I decided to go with the other solution.
> That's good, but again, this is a uapi file, not a "normal" include file
> in the kernel, you have to be careful about this.
>

Will do. Thanks for the quick responses.

BR,
Thinh

Re: [PATCH 01/11] usb: ch9: Add sublink speed struct

[-- Attachment #1: Type: text/plain, Size: 1422 bytes --]

Hi Thinh,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on balbi-usb/testing/next]
[also build test ERROR on usb/usb-testing peter.chen-usb/ci-for-usb-next linus/master v5.8-rc5 next-20200716]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Thinh-Nguyen/usb-Handle-different-sublink-speeds/20200717-060144
base:   https://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb.git testing/next
config: x86_64-randconfig-a005-20200717 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-14) 9.3.0
reproduce (this is a W=1 build):
        # save the attached .config to linux build tree
        make W=1 ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   In file included from ./usr/include/linux/usb/g_uvc.h:13,
                    from <command-line>:32:
>> ./usr/include/linux/usb/ch9.h:1184:2: error: unknown type name 'u8'
    1184 |  u8    id;
         |  ^~
>> ./usr/include/linux/usb/ch9.h:1185:2: error: unknown type name 'u16'
    1185 |  u16    mantissa;
         |  ^~~

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 29493 bytes --]

Re: [PATCH 01/11] usb: ch9: Add sublink speed struct

[kernel test robot]

[-- Attachment #1: Type: text/plain, Size: 1459 bytes --]

Hi Thinh,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on balbi-usb/testing/next]
[also build test ERROR on usb/usb-testing peter.chen-usb/ci-for-usb-next linus/master v5.8-rc5 next-20200716]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Thinh-Nguyen/usb-Handle-different-sublink-speeds/20200717-060144
base:   https://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb.git testing/next
config: x86_64-randconfig-a005-20200717 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-14) 9.3.0
reproduce (this is a W=1 build):
        # save the attached .config to linux build tree
        make W=1 ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   In file included from ./usr/include/linux/usb/g_uvc.h:13,
                    from <command-line>:32:
>> ./usr/include/linux/usb/ch9.h:1184:2: error: unknown type name 'u8'
    1184 |  u8    id;
         |  ^~
>> ./usr/include/linux/usb/ch9.h:1185:2: error: unknown type name 'u16'
    1185 |  u16    mantissa;
         |  ^~~

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org

[-- Attachment #2: config.gz --]
[-- Type: application/gzip, Size: 29493 bytes --]

Re: [PATCH 01/11] usb: ch9: Add sublink speed struct

[Sergei Shtylyov]

Hello!

On 17.07.2020 0:58, Thinh Nguyen wrote:

> 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
> 
> Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
> ---
>   include/uapi/linux/usb/ch9.h | 42 ++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 42 insertions(+)
> 
> diff --git a/include/uapi/linux/usb/ch9.h b/include/uapi/linux/usb/ch9.h
> index 2b623f36af6b..d4fd403a3664 100644
> --- a/include/uapi/linux/usb/ch9.h
> +++ b/include/uapi/linux/usb/ch9.h
> @@ -1145,6 +1145,48 @@ enum usb_device_speed {
>   	USB_SPEED_SUPER_PLUS,			/* usb 3.1 */
>   };
>   
> +/* 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
> + * @sublink type: sublink type

    It's called just 'type' below.

> + * @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;
> +};
>   
>   enum usb_device_state {
>   	/* NOTATTACHED isn't in the USB spec, and this state acts

MBR, Sergei

Re: [PATCH 01/11] usb: ch9: Add sublink speed struct

[Thinh Nguyen]

Sergei Shtylyov wrote:
> Hello!
>
> On 17.07.2020 0:58, Thinh Nguyen wrote:
>
>> 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
>>
>> Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
>> ---
>>   include/uapi/linux/usb/ch9.h | 42 
>> ++++++++++++++++++++++++++++++++++++++++++
>>   1 file changed, 42 insertions(+)
>>
>> diff --git a/include/uapi/linux/usb/ch9.h b/include/uapi/linux/usb/ch9.h
>> index 2b623f36af6b..d4fd403a3664 100644
>> --- a/include/uapi/linux/usb/ch9.h
>> +++ b/include/uapi/linux/usb/ch9.h
>> @@ -1145,6 +1145,48 @@ enum usb_device_speed {
>>       USB_SPEED_SUPER_PLUS,            /* usb 3.1 */
>>   };
>>   +/* 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
>> + * @sublink type: sublink type
>
>    It's called just 'type' below.
>

Will fix.

Thanks,
Thinh

Re: [PATCH 01/11] usb: ch9: Add sublink speed struct

[kernel test robot]

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Hi Thinh,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on balbi-usb/testing/next]
[also build test ERROR on usb/usb-testing peter.chen-usb/ci-for-usb-next linus/master v5.8-rc5 next-20200717]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Thinh-Nguyen/usb-Handle-different-sublink-speeds/20200717-060144
base:   https://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb.git testing/next
config: x86_64-allyesconfig (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project ed6b578040a85977026c93bf4188f996148f3218)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install x86_64 cross compiling tool for clang build
        # apt-get install binutils-x86-64-linux-gnu
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   In file included from <built-in>:1:
>> ./usr/include/linux/usb/ch9.h:1184:2: error: unknown type name 'u8'
           u8                              id;
           ^
>> ./usr/include/linux/usb/ch9.h:1185:2: error: unknown type name 'u16'
           u16                             mantissa;
           ^
   2 errors generated.

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 74010 bytes --]

Re: [PATCH 01/11] usb: ch9: Add sublink speed struct

[kernel test robot]

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Hi Thinh,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on balbi-usb/testing/next]
[also build test ERROR on usb/usb-testing peter.chen-usb/ci-for-usb-next linus/master v5.8-rc5 next-20200717]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Thinh-Nguyen/usb-Handle-different-sublink-speeds/20200717-060144
base:   https://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb.git testing/next
config: x86_64-allyesconfig (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project ed6b578040a85977026c93bf4188f996148f3218)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install x86_64 cross compiling tool for clang build
        # apt-get install binutils-x86-64-linux-gnu
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   In file included from <built-in>:1:
>> ./usr/include/linux/usb/ch9.h:1184:2: error: unknown type name 'u8'
           u8                              id;
           ^
>> ./usr/include/linux/usb/ch9.h:1185:2: error: unknown type name 'u16'
           u16                             mantissa;
           ^
   2 errors generated.

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org

[-- Attachment #2: config.gz --]
[-- Type: application/gzip, Size: 74010 bytes --]

Re: [PATCH 06/11] usb: devicetree: dwc3: Introduce num-lanes and lsm

[Rob Herring]

On Thu, Jul 16, 2020 at 02:59:08PM -0700, Thinh Nguyen wrote:
> Introduce num-lanes and lane-speed-mantissa-gbps for devices operating
> in super-speed-plus. DWC_usb32 IP supports multiple lanes and can
> operate in different sublink speeds. Currently the device controller
> does not have the information of the phy's number of lanes supported. As
> a result, the user can specify them through these properties if they are
> different than the default setting.
> 
> Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
> ---
>  Documentation/devicetree/bindings/usb/dwc3.txt | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt b/Documentation/devicetree/bindings/usb/dwc3.txt
> index d03edf9d3935..4eba0615562f 100644
> --- a/Documentation/devicetree/bindings/usb/dwc3.txt
> +++ b/Documentation/devicetree/bindings/usb/dwc3.txt
> @@ -86,6 +86,15 @@ Optional properties:
>   - snps,quirk-frame-length-adjustment: Value for GFLADJ_30MHZ field of GFLADJ
>  	register for post-silicon frame length adjustment when the
>  	fladj_30mhz_sdbnd signal is invalid or incorrect.
> + - snps,num-lanes: set to specify the number of lanes to use. Valid inputs are
> +			1 or 2. Apply if the maximum-speed is super-speed-plus
> +			only. Default value is 2 for DWC_usb32. For DWC_usb31,
> +			it is always 1 at super-speed-plus.
> + - snps,lane-speed-mantissa-gbps: set to specify the symmetric lane speed
> +			mantissa in Gbps. Valid inputs are 5 or 10. Apply if
> +			the maximum-speed is super-speed-plus only. Default
> +			value is 10. For DWC_usb31, it's always 10 at
> +			super-speed-plus.

This is all common USB things and should be common properties (which we 
may already have).

Rob

Re: [PATCH 06/11] usb: devicetree: dwc3: Introduce num-lanes and lsm

[Thinh Nguyen]

Rob Herring wrote:
> On Thu, Jul 16, 2020 at 02:59:08PM -0700, Thinh Nguyen wrote:
>> Introduce num-lanes and lane-speed-mantissa-gbps for devices operating
>> in super-speed-plus. DWC_usb32 IP supports multiple lanes and can
>> operate in different sublink speeds. Currently the device controller
>> does not have the information of the phy's number of lanes supported. As
>> a result, the user can specify them through these properties if they are
>> different than the default setting.
>>
>> Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
>> ---
>>   Documentation/devicetree/bindings/usb/dwc3.txt | 9 +++++++++
>>   1 file changed, 9 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt b/Documentation/devicetree/bindings/usb/dwc3.txt
>> index d03edf9d3935..4eba0615562f 100644
>> --- a/Documentation/devicetree/bindings/usb/dwc3.txt
>> +++ b/Documentation/devicetree/bindings/usb/dwc3.txt
>> @@ -86,6 +86,15 @@ Optional properties:
>>    - snps,quirk-frame-length-adjustment: Value for GFLADJ_30MHZ field of GFLADJ
>>   	register for post-silicon frame length adjustment when the
>>   	fladj_30mhz_sdbnd signal is invalid or incorrect.
>> + - snps,num-lanes: set to specify the number of lanes to use. Valid inputs are
>> +			1 or 2. Apply if the maximum-speed is super-speed-plus
>> +			only. Default value is 2 for DWC_usb32. For DWC_usb31,
>> +			it is always 1 at super-speed-plus.
>> + - snps,lane-speed-mantissa-gbps: set to specify the symmetric lane speed
>> +			mantissa in Gbps. Valid inputs are 5 or 10. Apply if
>> +			the maximum-speed is super-speed-plus only. Default
>> +			value is 10. For DWC_usb31, it's always 10 at
>> +			super-speed-plus.
> This is all common USB things and should be common properties (which we
> may already have).

Sure. For "num-lanes" is simple, any objection if we use 
"lane-speed-mantissa-gbps"? Or should we add "lane-speed-exponent"?

Thanks,
Thinh

Re: [PATCH 06/11] usb: devicetree: dwc3: Introduce num-lanes and lsm

[Rob Herring]

On Mon, Jul 20, 2020 at 11:01 PM Thinh Nguyen <Thinh.Nguyen@synopsys.com> wrote:
>
> Rob Herring wrote:
> > On Thu, Jul 16, 2020 at 02:59:08PM -0700, Thinh Nguyen wrote:
> >> Introduce num-lanes and lane-speed-mantissa-gbps for devices operating
> >> in super-speed-plus. DWC_usb32 IP supports multiple lanes and can
> >> operate in different sublink speeds. Currently the device controller
> >> does not have the information of the phy's number of lanes supported. As
> >> a result, the user can specify them through these properties if they are
> >> different than the default setting.
> >>
> >> Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
> >> ---
> >>   Documentation/devicetree/bindings/usb/dwc3.txt | 9 +++++++++
> >>   1 file changed, 9 insertions(+)
> >>
> >> diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt b/Documentation/devicetree/bindings/usb/dwc3.txt
> >> index d03edf9d3935..4eba0615562f 100644
> >> --- a/Documentation/devicetree/bindings/usb/dwc3.txt
> >> +++ b/Documentation/devicetree/bindings/usb/dwc3.txt
> >> @@ -86,6 +86,15 @@ Optional properties:
> >>    - snps,quirk-frame-length-adjustment: Value for GFLADJ_30MHZ field of GFLADJ
> >>      register for post-silicon frame length adjustment when the
> >>      fladj_30mhz_sdbnd signal is invalid or incorrect.
> >> + - snps,num-lanes: set to specify the number of lanes to use. Valid inputs are
> >> +                    1 or 2. Apply if the maximum-speed is super-speed-plus
> >> +                    only. Default value is 2 for DWC_usb32. For DWC_usb31,
> >> +                    it is always 1 at super-speed-plus.
> >> + - snps,lane-speed-mantissa-gbps: set to specify the symmetric lane speed
> >> +                    mantissa in Gbps. Valid inputs are 5 or 10. Apply if
> >> +                    the maximum-speed is super-speed-plus only. Default
> >> +                    value is 10. For DWC_usb31, it's always 10 at
> >> +                    super-speed-plus.
> > This is all common USB things and should be common properties (which we
> > may already have).
>
> Sure. For "num-lanes" is simple, any objection if we use
> "lane-speed-mantissa-gbps"? Or should we add "lane-speed-exponent"?

'num-lanes' is good as that's what PCIe uses. Document that with
'maximum-speed'.

I think 'super-speed-plus' should mean gen 2 10G per lane. Then
between num-lanes and maximum-speed you can define all 4 possible
rates.

Rob

Re: [PATCH 06/11] usb: devicetree: dwc3: Introduce num-lanes and lsm

[Thinh Nguyen]

Rob Herring wrote:
> On Mon, Jul 20, 2020 at 11:01 PM Thinh Nguyen <Thinh.Nguyen@synopsys.com> wrote:
>> Rob Herring wrote:
>>> On Thu, Jul 16, 2020 at 02:59:08PM -0700, Thinh Nguyen wrote:
>>>> Introduce num-lanes and lane-speed-mantissa-gbps for devices operating
>>>> in super-speed-plus. DWC_usb32 IP supports multiple lanes and can
>>>> operate in different sublink speeds. Currently the device controller
>>>> does not have the information of the phy's number of lanes supported. As
>>>> a result, the user can specify them through these properties if they are
>>>> different than the default setting.
>>>>
>>>> Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
>>>> ---
>>>>    Documentation/devicetree/bindings/usb/dwc3.txt | 9 +++++++++
>>>>    1 file changed, 9 insertions(+)
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt b/Documentation/devicetree/bindings/usb/dwc3.txt
>>>> index d03edf9d3935..4eba0615562f 100644
>>>> --- a/Documentation/devicetree/bindings/usb/dwc3.txt
>>>> +++ b/Documentation/devicetree/bindings/usb/dwc3.txt
>>>> @@ -86,6 +86,15 @@ Optional properties:
>>>>     - snps,quirk-frame-length-adjustment: Value for GFLADJ_30MHZ field of GFLADJ
>>>>       register for post-silicon frame length adjustment when the
>>>>       fladj_30mhz_sdbnd signal is invalid or incorrect.
>>>> + - snps,num-lanes: set to specify the number of lanes to use. Valid inputs are
>>>> +                    1 or 2. Apply if the maximum-speed is super-speed-plus
>>>> +                    only. Default value is 2 for DWC_usb32. For DWC_usb31,
>>>> +                    it is always 1 at super-speed-plus.
>>>> + - snps,lane-speed-mantissa-gbps: set to specify the symmetric lane speed
>>>> +                    mantissa in Gbps. Valid inputs are 5 or 10. Apply if
>>>> +                    the maximum-speed is super-speed-plus only. Default
>>>> +                    value is 10. For DWC_usb31, it's always 10 at
>>>> +                    super-speed-plus.
>>> This is all common USB things and should be common properties (which we
>>> may already have).
>> Sure. For "num-lanes" is simple, any objection if we use
>> "lane-speed-mantissa-gbps"? Or should we add "lane-speed-exponent"?
> 'num-lanes' is good as that's what PCIe uses. Document that with
> 'maximum-speed'.
>
> I think 'super-speed-plus' should mean gen 2 10G per lane. Then
> between num-lanes and maximum-speed you can define all 4 possible
> rates.

That may confuse the user because now we'd use 'super-speed-plus' to 
define the speed of the lane rather than the device itself.

According to the USB 3.2 spec, super-speed-plus can mean gen2x1, gen1x2, 
or gen2x2.

BR,
Thinh

Re: [PATCH 06/11] usb: devicetree: dwc3: Introduce num-lanes and lsm

[Felipe Balbi]

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Hi,

Thinh Nguyen <Thinh.Nguyen@synopsys.com> writes:
> Rob Herring wrote:
>> On Mon, Jul 20, 2020 at 11:01 PM Thinh Nguyen <Thinh.Nguyen@synopsys.com> wrote:
>>> Rob Herring wrote:
>>>> On Thu, Jul 16, 2020 at 02:59:08PM -0700, Thinh Nguyen wrote:
>>>>> Introduce num-lanes and lane-speed-mantissa-gbps for devices operating
>>>>> in super-speed-plus. DWC_usb32 IP supports multiple lanes and can
>>>>> operate in different sublink speeds. Currently the device controller
>>>>> does not have the information of the phy's number of lanes supported. As
>>>>> a result, the user can specify them through these properties if they are
>>>>> different than the default setting.
>>>>>
>>>>> Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
>>>>> ---
>>>>>    Documentation/devicetree/bindings/usb/dwc3.txt | 9 +++++++++
>>>>>    1 file changed, 9 insertions(+)
>>>>>
>>>>> diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt b/Documentation/devicetree/bindings/usb/dwc3.txt
>>>>> index d03edf9d3935..4eba0615562f 100644
>>>>> --- a/Documentation/devicetree/bindings/usb/dwc3.txt
>>>>> +++ b/Documentation/devicetree/bindings/usb/dwc3.txt
>>>>> @@ -86,6 +86,15 @@ Optional properties:
>>>>>     - snps,quirk-frame-length-adjustment: Value for GFLADJ_30MHZ field of GFLADJ
>>>>>       register for post-silicon frame length adjustment when the
>>>>>       fladj_30mhz_sdbnd signal is invalid or incorrect.
>>>>> + - snps,num-lanes: set to specify the number of lanes to use. Valid inputs are
>>>>> +                    1 or 2. Apply if the maximum-speed is super-speed-plus
>>>>> +                    only. Default value is 2 for DWC_usb32. For DWC_usb31,
>>>>> +                    it is always 1 at super-speed-plus.
>>>>> + - snps,lane-speed-mantissa-gbps: set to specify the symmetric lane speed
>>>>> +                    mantissa in Gbps. Valid inputs are 5 or 10. Apply if
>>>>> +                    the maximum-speed is super-speed-plus only. Default
>>>>> +                    value is 10. For DWC_usb31, it's always 10 at
>>>>> +                    super-speed-plus.
>>>> This is all common USB things and should be common properties (which we
>>>> may already have).
>>> Sure. For "num-lanes" is simple, any objection if we use
>>> "lane-speed-mantissa-gbps"? Or should we add "lane-speed-exponent"?
>> 'num-lanes' is good as that's what PCIe uses. Document that with
>> 'maximum-speed'.
>>
>> I think 'super-speed-plus' should mean gen 2 10G per lane. Then
>> between num-lanes and maximum-speed you can define all 4 possible
>> rates.
>
> That may confuse the user because now we'd use 'super-speed-plus' to 
> define the speed of the lane rather than the device itself.

I agree. In USB land we should refer solely to the USB specification
naming schemes.

-- 
balbi

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Re: [PATCH 06/11] usb: devicetree: dwc3: Introduce num-lanes and lsm

[Rob Herring]

On Tue, Jul 21, 2020 at 10:42 AM Thinh Nguyen <Thinh.Nguyen@synopsys.com> wrote:
>
> Rob Herring wrote:
> > On Mon, Jul 20, 2020 at 11:01 PM Thinh Nguyen <Thinh.Nguyen@synopsys.com> wrote:
> >> Rob Herring wrote:
> >>> On Thu, Jul 16, 2020 at 02:59:08PM -0700, Thinh Nguyen wrote:
> >>>> Introduce num-lanes and lane-speed-mantissa-gbps for devices operating
> >>>> in super-speed-plus. DWC_usb32 IP supports multiple lanes and can
> >>>> operate in different sublink speeds. Currently the device controller
> >>>> does not have the information of the phy's number of lanes supported. As
> >>>> a result, the user can specify them through these properties if they are
> >>>> different than the default setting.
> >>>>
> >>>> Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
> >>>> ---
> >>>>    Documentation/devicetree/bindings/usb/dwc3.txt | 9 +++++++++
> >>>>    1 file changed, 9 insertions(+)
> >>>>
> >>>> diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt b/Documentation/devicetree/bindings/usb/dwc3.txt
> >>>> index d03edf9d3935..4eba0615562f 100644
> >>>> --- a/Documentation/devicetree/bindings/usb/dwc3.txt
> >>>> +++ b/Documentation/devicetree/bindings/usb/dwc3.txt
> >>>> @@ -86,6 +86,15 @@ Optional properties:
> >>>>     - snps,quirk-frame-length-adjustment: Value for GFLADJ_30MHZ field of GFLADJ
> >>>>       register for post-silicon frame length adjustment when the
> >>>>       fladj_30mhz_sdbnd signal is invalid or incorrect.
> >>>> + - snps,num-lanes: set to specify the number of lanes to use. Valid inputs are
> >>>> +                    1 or 2. Apply if the maximum-speed is super-speed-plus
> >>>> +                    only. Default value is 2 for DWC_usb32. For DWC_usb31,
> >>>> +                    it is always 1 at super-speed-plus.
> >>>> + - snps,lane-speed-mantissa-gbps: set to specify the symmetric lane speed
> >>>> +                    mantissa in Gbps. Valid inputs are 5 or 10. Apply if
> >>>> +                    the maximum-speed is super-speed-plus only. Default
> >>>> +                    value is 10. For DWC_usb31, it's always 10 at
> >>>> +                    super-speed-plus.
> >>> This is all common USB things and should be common properties (which we
> >>> may already have).
> >> Sure. For "num-lanes" is simple, any objection if we use
> >> "lane-speed-mantissa-gbps"? Or should we add "lane-speed-exponent"?
> > 'num-lanes' is good as that's what PCIe uses. Document that with
> > 'maximum-speed'.
> >
> > I think 'super-speed-plus' should mean gen 2 10G per lane. Then
> > between num-lanes and maximum-speed you can define all 4 possible
> > rates.
>
> That may confuse the user because now we'd use 'super-speed-plus' to
> define the speed of the lane rather than the device itself.
>
> According to the USB 3.2 spec, super-speed-plus can mean gen2x1, gen1x2,
> or gen2x2.

Then add new strings as needed to make it clear: super-speed-plus-gen1x2

It's obvious that what 'super-speed-plus' means is not clear since
USB-IF extended its meaning.

Rob

Re: [PATCH 06/11] usb: devicetree: dwc3: Introduce num-lanes and lsm

[Thinh Nguyen]

Rob Herring wrote:
> On Tue, Jul 21, 2020 at 10:42 AM Thinh Nguyen <Thinh.Nguyen@synopsys.com> wrote:
>> Rob Herring wrote:
>>> On Mon, Jul 20, 2020 at 11:01 PM Thinh Nguyen <Thinh.Nguyen@synopsys.com> wrote:
>>>> Rob Herring wrote:
>>>>> On Thu, Jul 16, 2020 at 02:59:08PM -0700, Thinh Nguyen wrote:
>>>>>> Introduce num-lanes and lane-speed-mantissa-gbps for devices operating
>>>>>> in super-speed-plus. DWC_usb32 IP supports multiple lanes and can
>>>>>> operate in different sublink speeds. Currently the device controller
>>>>>> does not have the information of the phy's number of lanes supported. As
>>>>>> a result, the user can specify them through these properties if they are
>>>>>> different than the default setting.
>>>>>>
>>>>>> Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
>>>>>> ---
>>>>>>     Documentation/devicetree/bindings/usb/dwc3.txt | 9 +++++++++
>>>>>>     1 file changed, 9 insertions(+)
>>>>>>
>>>>>> diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt b/Documentation/devicetree/bindings/usb/dwc3.txt
>>>>>> index d03edf9d3935..4eba0615562f 100644
>>>>>> --- a/Documentation/devicetree/bindings/usb/dwc3.txt
>>>>>> +++ b/Documentation/devicetree/bindings/usb/dwc3.txt
>>>>>> @@ -86,6 +86,15 @@ Optional properties:
>>>>>>      - snps,quirk-frame-length-adjustment: Value for GFLADJ_30MHZ field of GFLADJ
>>>>>>        register for post-silicon frame length adjustment when the
>>>>>>        fladj_30mhz_sdbnd signal is invalid or incorrect.
>>>>>> + - snps,num-lanes: set to specify the number of lanes to use. Valid inputs are
>>>>>> +                    1 or 2. Apply if the maximum-speed is super-speed-plus
>>>>>> +                    only. Default value is 2 for DWC_usb32. For DWC_usb31,
>>>>>> +                    it is always 1 at super-speed-plus.
>>>>>> + - snps,lane-speed-mantissa-gbps: set to specify the symmetric lane speed
>>>>>> +                    mantissa in Gbps. Valid inputs are 5 or 10. Apply if
>>>>>> +                    the maximum-speed is super-speed-plus only. Default
>>>>>> +                    value is 10. For DWC_usb31, it's always 10 at
>>>>>> +                    super-speed-plus.
>>>>> This is all common USB things and should be common properties (which we
>>>>> may already have).
>>>> Sure. For "num-lanes" is simple, any objection if we use
>>>> "lane-speed-mantissa-gbps"? Or should we add "lane-speed-exponent"?
>>> 'num-lanes' is good as that's what PCIe uses. Document that with
>>> 'maximum-speed'.
>>>
>>> I think 'super-speed-plus' should mean gen 2 10G per lane. Then
>>> between num-lanes and maximum-speed you can define all 4 possible
>>> rates.
>> That may confuse the user because now we'd use 'super-speed-plus' to
>> define the speed of the lane rather than the device itself.
>>
>> According to the USB 3.2 spec, super-speed-plus can mean gen2x1, gen1x2,
>> or gen2x2.
> Then add new strings as needed to make it clear: super-speed-plus-gen1x2
>
> It's obvious that what 'super-speed-plus' means is not clear since
> USB-IF extended its meaning.
>
> Rob

If we introduce a new enum for gen1x2, now we'd have to go back and 
inspect all the checks for all the drivers where for example speed == 
USB_SPEED_SUPER_PLUS. It seems to be more clunky and may introduce more 
bugs.

BR,
Thinh

Re: [PATCH 06/11] usb: devicetree: dwc3: Introduce num-lanes and lsm

[Thinh Nguyen]

Thinh Nguyen wrote:
> Rob Herring wrote:
>> On Tue, Jul 21, 2020 at 10:42 AM Thinh Nguyen <Thinh.Nguyen@synopsys.com> wrote:
>>> Rob Herring wrote:
>>>> On Mon, Jul 20, 2020 at 11:01 PM Thinh Nguyen <Thinh.Nguyen@synopsys.com> wrote:
>>>>> Rob Herring wrote:
>>>>>> On Thu, Jul 16, 2020 at 02:59:08PM -0700, Thinh Nguyen wrote:
>>>>>>> Introduce num-lanes and lane-speed-mantissa-gbps for devices operating
>>>>>>> in super-speed-plus. DWC_usb32 IP supports multiple lanes and can
>>>>>>> operate in different sublink speeds. Currently the device controller
>>>>>>> does not have the information of the phy's number of lanes supported. As
>>>>>>> a result, the user can specify them through these properties if they are
>>>>>>> different than the default setting.
>>>>>>>
>>>>>>> Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
>>>>>>> ---
>>>>>>>      Documentation/devicetree/bindings/usb/dwc3.txt | 9 +++++++++
>>>>>>>      1 file changed, 9 insertions(+)
>>>>>>>
>>>>>>> diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt b/Documentation/devicetree/bindings/usb/dwc3.txt
>>>>>>> index d03edf9d3935..4eba0615562f 100644
>>>>>>> --- a/Documentation/devicetree/bindings/usb/dwc3.txt
>>>>>>> +++ b/Documentation/devicetree/bindings/usb/dwc3.txt
>>>>>>> @@ -86,6 +86,15 @@ Optional properties:
>>>>>>>       - snps,quirk-frame-length-adjustment: Value for GFLADJ_30MHZ field of GFLADJ
>>>>>>>         register for post-silicon frame length adjustment when the
>>>>>>>         fladj_30mhz_sdbnd signal is invalid or incorrect.
>>>>>>> + - snps,num-lanes: set to specify the number of lanes to use. Valid inputs are
>>>>>>> +                    1 or 2. Apply if the maximum-speed is super-speed-plus
>>>>>>> +                    only. Default value is 2 for DWC_usb32. For DWC_usb31,
>>>>>>> +                    it is always 1 at super-speed-plus.
>>>>>>> + - snps,lane-speed-mantissa-gbps: set to specify the symmetric lane speed
>>>>>>> +                    mantissa in Gbps. Valid inputs are 5 or 10. Apply if
>>>>>>> +                    the maximum-speed is super-speed-plus only. Default
>>>>>>> +                    value is 10. For DWC_usb31, it's always 10 at
>>>>>>> +                    super-speed-plus.
>>>>>> This is all common USB things and should be common properties (which we
>>>>>> may already have).
>>>>> Sure. For "num-lanes" is simple, any objection if we use
>>>>> "lane-speed-mantissa-gbps"? Or should we add "lane-speed-exponent"?
>>>> 'num-lanes' is good as that's what PCIe uses. Document that with
>>>> 'maximum-speed'.
>>>>
>>>> I think 'super-speed-plus' should mean gen 2 10G per lane. Then
>>>> between num-lanes and maximum-speed you can define all 4 possible
>>>> rates.
>>> That may confuse the user because now we'd use 'super-speed-plus' to
>>> define the speed of the lane rather than the device itself.
>>>
>>> According to the USB 3.2 spec, super-speed-plus can mean gen2x1, gen1x2,
>>> or gen2x2.
>> Then add new strings as needed to make it clear: super-speed-plus-gen1x2
>>
>> It's obvious that what 'super-speed-plus' means is not clear since
>> USB-IF extended its meaning.
>>
>> Rob
> If we introduce a new enum for gen1x2, now we'd have to go back and
> inspect all the checks for all the drivers where for example speed ==
> USB_SPEED_SUPER_PLUS. It seems to be more clunky and may introduce more
> bugs.
>

In my opinion, the better option would be to introduce a new property 
for lane speed such as "lane-speed-mantissa-gbps" because:

1) It still follows the spec, easier for the user to understand
2) We only need to update the drivers where the number of lanes and lane 
speed matter
3) Easier speed comparison between usb_device_speed enum
4) Easier to backport new code where there's speed comparison
5) Easily extendable to new/different lane speeds

BR,
Thinh

Re: [PATCH 06/11] usb: devicetree: dwc3: Introduce num-lanes and lsm

[Thinh Nguyen]

Thinh Nguyen wrote:
> Thinh Nguyen wrote:
>> Rob Herring wrote:
>>> On Tue, Jul 21, 2020 at 10:42 AM Thinh Nguyen <Thinh.Nguyen@synopsys.com> wrote:
>>>> Rob Herring wrote:
>>>>> On Mon, Jul 20, 2020 at 11:01 PM Thinh Nguyen <Thinh.Nguyen@synopsys.com> wrote:
>>>>>> Rob Herring wrote:
>>>>>>> On Thu, Jul 16, 2020 at 02:59:08PM -0700, Thinh Nguyen wrote:
>>>>>>>> Introduce num-lanes and lane-speed-mantissa-gbps for devices operating
>>>>>>>> in super-speed-plus. DWC_usb32 IP supports multiple lanes and can
>>>>>>>> operate in different sublink speeds. Currently the device controller
>>>>>>>> does not have the information of the phy's number of lanes supported. As
>>>>>>>> a result, the user can specify them through these properties if they are
>>>>>>>> different than the default setting.
>>>>>>>>
>>>>>>>> Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
>>>>>>>> ---
>>>>>>>>       Documentation/devicetree/bindings/usb/dwc3.txt | 9 +++++++++
>>>>>>>>       1 file changed, 9 insertions(+)
>>>>>>>>
>>>>>>>> diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt b/Documentation/devicetree/bindings/usb/dwc3.txt
>>>>>>>> index d03edf9d3935..4eba0615562f 100644
>>>>>>>> --- a/Documentation/devicetree/bindings/usb/dwc3.txt
>>>>>>>> +++ b/Documentation/devicetree/bindings/usb/dwc3.txt
>>>>>>>> @@ -86,6 +86,15 @@ Optional properties:
>>>>>>>>        - snps,quirk-frame-length-adjustment: Value for GFLADJ_30MHZ field of GFLADJ
>>>>>>>>          register for post-silicon frame length adjustment when the
>>>>>>>>          fladj_30mhz_sdbnd signal is invalid or incorrect.
>>>>>>>> + - snps,num-lanes: set to specify the number of lanes to use. Valid inputs are
>>>>>>>> +                    1 or 2. Apply if the maximum-speed is super-speed-plus
>>>>>>>> +                    only. Default value is 2 for DWC_usb32. For DWC_usb31,
>>>>>>>> +                    it is always 1 at super-speed-plus.
>>>>>>>> + - snps,lane-speed-mantissa-gbps: set to specify the symmetric lane speed
>>>>>>>> +                    mantissa in Gbps. Valid inputs are 5 or 10. Apply if
>>>>>>>> +                    the maximum-speed is super-speed-plus only. Default
>>>>>>>> +                    value is 10. For DWC_usb31, it's always 10 at
>>>>>>>> +                    super-speed-plus.
>>>>>>> This is all common USB things and should be common properties (which we
>>>>>>> may already have).
>>>>>> Sure. For "num-lanes" is simple, any objection if we use
>>>>>> "lane-speed-mantissa-gbps"? Or should we add "lane-speed-exponent"?
>>>>> 'num-lanes' is good as that's what PCIe uses. Document that with
>>>>> 'maximum-speed'.
>>>>>
>>>>> I think 'super-speed-plus' should mean gen 2 10G per lane. Then
>>>>> between num-lanes and maximum-speed you can define all 4 possible
>>>>> rates.
>>>> That may confuse the user because now we'd use 'super-speed-plus' to
>>>> define the speed of the lane rather than the device itself.
>>>>
>>>> According to the USB 3.2 spec, super-speed-plus can mean gen2x1, gen1x2,
>>>> or gen2x2.
>>> Then add new strings as needed to make it clear: super-speed-plus-gen1x2
>>>
>>> It's obvious that what 'super-speed-plus' means is not clear since
>>> USB-IF extended its meaning.
>>>
>>> Rob
>> If we introduce a new enum for gen1x2, now we'd have to go back and
>> inspect all the checks for all the drivers where for example speed ==
>> USB_SPEED_SUPER_PLUS. It seems to be more clunky and may introduce more
>> bugs.
>>
> In my opinion, the better option would be to introduce a new property
> for lane speed such as "lane-speed-mantissa-gbps" because:
>
> 1) It still follows the spec, easier for the user to understand
> 2) We only need to update the drivers where the number of lanes and lane
> speed matter
> 3) Easier speed comparison between usb_device_speed enum
> 4) Easier to backport new code where there's speed comparison
> 5) Easily extendable to new/different lane speeds
>

Let me send out v2 of this series so that others can also provide more 
feedback on other patches. We can continue with this discussion as 
needed in the meanwhile.

BR,
Thinh