[PATCH v2 00/12] usb: Handle different sublink speeds

[PATCH v2 00/12] 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.

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


Thinh Nguyen (12):
  usb: ch9: Add sublink speed struct
  usb: gadget: composite: Avoid using magic numbers
  usb: gadget: Expose sublink speed attributes
  usb: gadget: Set max speed for SSP devices
  usb: composite: Properly report sublink speed
  usb: devicetree: Introduce num-lanes and lsm
  usb: common: Add functions to get 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/generic.txt |  11 ++
 drivers/usb/common/common.c                       |  26 ++++
 drivers/usb/dwc3/core.c                           |  62 ++++++++++
 drivers/usb/dwc3/core.h                           |  18 +++
 drivers/usb/dwc3/gadget.c                         | 143 +++++++++++++++++++++-
 drivers/usb/gadget/composite.c                    |  81 ++++++++----
 drivers/usb/gadget/udc/core.c                     |  24 +++-
 include/linux/usb/ch9.h                           |  62 ++++++++++
 include/linux/usb/gadget.h                        |  23 ++++
 9 files changed, 414 insertions(+), 36 deletions(-)


base-commit: 5db5ea26a2469d8899f995e82e8b718dc9e9d168
-- 
2.11.0

[PATCH v2 01/12] 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>
---
Changes in v2:
- Move to include/linux/usb/ch9.h instead of under uapi

 include/linux/usb/ch9.h | 43 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 43 insertions(+)

diff --git a/include/linux/usb/ch9.h b/include/linux/usb/ch9.h
index 58b83066bea4..f87ef9a2f859 100644
--- a/include/linux/usb/ch9.h
+++ b/include/linux/usb/ch9.h
@@ -36,6 +36,49 @@
 #include <linux/device.h>
 #include <uapi/linux/usb/ch9.h>
 
+/* USB 3.2 sublink speed attributes */
+
+enum usb_lane_speed_exponent {
+	USB_LSE_BPS = 0,
+	USB_LSE_KBPS = 1,
+	USB_LSE_MBPS = 2,
+	USB_LSE_GBPS = 3,
+};
+
+enum usb_sublink_type {
+	USB_ST_SYMMETRIC_RX = 0,
+	USB_ST_ASYMMETRIC_RX = 1,
+	USB_ST_SYMMETRIC_TX = 2,
+	USB_ST_ASYMMETRIC_TX = 3,
+};
+
+enum usb_link_protocol {
+	USB_LP_SS = 0,
+	USB_LP_SSP = 1,
+};
+
+/**
+ * struct usb_sublink_speed - sublink speed attribute
+ * @id: sublink speed attribute ID (SSID)
+ * @mantissa: lane speed mantissa
+ * @exponent: lane speed exponent
+ * @type: sublink type
+ * @protocol: sublink protocol
+ *
+ * Super-speed-plus supports multiple lanes. Use the sublink speed attributes to
+ * describe the sublink speed.
+ *
+ * See USB 3.2 spec section 9.6.2.6 for super-speed-plus capability for more
+ * information.
+ */
+struct usb_sublink_speed {
+	u8				id;
+	u16				mantissa;
+	enum usb_lane_speed_exponent	exponent;
+	enum usb_sublink_type		type;
+	enum usb_link_protocol		protocol;
+};
+
 /**
  * usb_ep_type_string() - Returns human readable-name of the endpoint type.
  * @ep_type: The endpoint type to return human-readable name for.  If it's not
-- 
2.11.0

[PATCH v2 02/12] 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>
---
 Changes in v2:
 - None

 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 v2 03/12] 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>
---
 Changes in v2:
 - None

 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 v2 04/12] 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>
---
 Changes in v2:
 - None

 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 5241603bd008..5fea14cc9dbd 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 v2 05/12] 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>
---
 Changes in v2:
 - None

 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 v2 06/12] usb: devicetree: Introduce num-lanes and lsm

[Thinh Nguyen]

According to USB 3.2 spec, a super-speed-plus device can operate at
gen2x2, gen2x1, or gen1x2. Introduce "num-lanes" and
"lane-speed-mantissa-gbps" properties for devices operating in
super-speed-plus. If the USB controller device supports multiple lanes
at different transfer rate, the user can specify the HW capability via
these properties.

Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
---
Changes in v2:
- Make "num-lanes" and "lane-speed-mantissa-gbps" common USB properties

 Documentation/devicetree/bindings/usb/generic.txt | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/Documentation/devicetree/bindings/usb/generic.txt b/Documentation/devicetree/bindings/usb/generic.txt
index ba472e7aefc9..a8253da684af 100644
--- a/Documentation/devicetree/bindings/usb/generic.txt
+++ b/Documentation/devicetree/bindings/usb/generic.txt
@@ -7,6 +7,17 @@ Optional properties:
 			"low-speed". In case this isn't passed via DT, USB
 			controllers should default to their maximum HW
 			capability.
+ - num-lanes: tells USB controllers that we want to work up to a certain number
+			of lanes. Valid arguments are 1 or 2. Apply if the
+			maximum-speed is super-speed-plus. In case this isn't
+			passed via DT, the USB controllers should default to
+			their maximum HW capability.
+ - lane-speed-mantissa-gbps: tells USB controllers that we want the symmetric
+			lanes to operate up to a certain rate in Gbps. Valid
+			inputs are 5 or 10 (i.e. Gen 1/Gen 2 transfer rate).
+			Apply if the maximum-speed is super-speed-plus. In case
+			this isn't passed via DT, the USB controllers should
+			default to their maximum HW capability.
  - dr_mode: tells Dual-Role USB controllers that we want to work on a
 			particular mode. Valid arguments are "host",
 			"peripheral" and "otg". In case this attribute isn't
-- 
2.11.0

[PATCH v2 07/12] usb: common: Add functions to get lanes and lsm

[Thinh Nguyen]

Add common functions to get the requested number of lanes and lane speed
mantissa from device properties.

Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
---
Changes in v2:
- New commit

 drivers/usb/common/common.c | 26 ++++++++++++++++++++++++++
 include/linux/usb/ch9.h     | 19 +++++++++++++++++++
 2 files changed, 45 insertions(+)

diff --git a/drivers/usb/common/common.c b/drivers/usb/common/common.c
index 1433260d99b4..871a7326b6b7 100644
--- a/drivers/usb/common/common.c
+++ b/drivers/usb/common/common.c
@@ -92,6 +92,32 @@ enum usb_device_speed usb_get_maximum_speed(struct device *dev)
 }
 EXPORT_SYMBOL_GPL(usb_get_maximum_speed);
 
+u8 usb_get_num_lanes(struct device *dev)
+{
+	u8 num_lanes;
+	int ret;
+
+	ret = device_property_read_u8(dev, "num-lanes", &num_lanes);
+	if (ret < 0)
+		return 0;
+
+	return num_lanes;
+}
+EXPORT_SYMBOL_GPL(usb_get_num_lanes);
+
+u16 usb_get_lsm(struct device *dev)
+{
+	u16 lsm;
+	int ret;
+
+	ret = device_property_read_u16(dev, "lane-speed-mantissa-gbps", &lsm);
+	if (ret < 0)
+		return 0;
+
+	return lsm;
+}
+EXPORT_SYMBOL_GPL(usb_get_lsm);
+
 const char *usb_state_string(enum usb_device_state state)
 {
 	static const char *const names[] = {
diff --git a/include/linux/usb/ch9.h b/include/linux/usb/ch9.h
index f87ef9a2f859..1097c6f8e2ef 100644
--- a/include/linux/usb/ch9.h
+++ b/include/linux/usb/ch9.h
@@ -105,6 +105,25 @@ extern const char *usb_speed_string(enum usb_device_speed speed);
  */
 extern enum usb_device_speed usb_get_maximum_speed(struct device *dev);
 
+/**
+ * usb_get_num_lanes - Get maximum number of requested lanes for a given USB
+ * controller.
+ * @dev: Pointer to the given USB controller device
+ *
+ * The function returns the number of requested lanes from the property
+ * "num-lanes".
+ */
+extern u8 usb_get_num_lanes(struct device *dev);
+
+/**
+ * usb_get_lsm - Get requested lane speed mantissa for a given USB controller.
+ * @dev: Pointer to the given USB controller device
+ *
+ * The function returns the requested symmetric lane speed mantissa in Gbps from
+ * the property "lane-speed-mantissa-gbps".
+ */
+extern u16 usb_get_lsm(struct device *dev);
+
 /**
  * usb_state_string - Returns human readable name for the state.
  * @state: The state to return a human-readable name for. If it's not
-- 
2.11.0

[PATCH v2 08/12] 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>
---
Changes in v2:
- Use common functions to get num_lanes and lsm properties

 drivers/usb/dwc3/core.c | 62 +++++++++++++++++++++++++++++++++++++++++++++++++
 drivers/usb/dwc3/core.h | 10 ++++++++
 2 files changed, 72 insertions(+)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 25c686a752b0..d9b8e3f8d005 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -1275,6 +1275,8 @@ static void dwc3_get_properties(struct dwc3 *dwc)
 	hird_threshold = 12;
 
 	dwc->maximum_speed = usb_get_maximum_speed(dev);
+	dwc->maximum_num_lanes = usb_get_num_lanes(dev);
+	dwc->maximum_lsm = usb_get_lsm(dev);
 	dwc->dr_mode = usb_get_dr_mode(dev);
 	dwc->hsphy_mode = of_usb_get_phy_mode(dev->of_node);
 
@@ -1426,6 +1428,66 @@ 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..0e37a0471e5a 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;
+	u16			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 v2 09/12] 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>
---
Changes in v2:
- Fix missing check for gen1x2 when writing to sublink speed attributes
- Minor fix in commit message (first commit sentence ended with comma)

 drivers/usb/dwc3/core.h   |  4 ++++
 drivers/usb/dwc3/gadget.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 53 insertions(+)

diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 0e37a0471e5a..b44550173599 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..69f64bb324ed 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -3662,6 +3662,55 @@ 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 if (dwc->maximum_lsm == DWC3_LSM_5_GBPS &&
+			   dwc->maximum_num_lanes == 2) {
+			dwc->gadget.ssac = 1;
+			dwc->gadget.min_speed_ssid = DWC3_SSP_SSID_GEN1;
+			dwc->gadget.max_speed_ssid = DWC3_SSP_SSID_GEN1;
+		} 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 (dwc->gadget.ssac > 1 && i > 1)
+				ssa->id = dwc->gadget.max_speed_ssid;
+			else
+				ssa->id = dwc->gadget.min_speed_ssid;
+
+			if (ssa->id == DWC3_SSP_SSID_GEN1)
+				ssa->mantissa = DWC3_LSM_5_GBPS;
+			else
+				ssa->mantissa = DWC3_LSM_10_GBPS;
+
+			/* First attribute is RX followed by TX */
+			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 v2 10/12] 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>
---
 Changes in v2:
 - None

 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 b44550173599..36407a8e67b8 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 69f64bb324ed..5671a6762c83 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,
 };
 
@@ -3727,7 +3784,12 @@ 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 v2 11/12] 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>
---
 Changes in v2:
 - None

 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 36407a8e67b8..84e2150c1c0a 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 5671a6762c83..2bc29d74e75a 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 v2 12/12] 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>
---
 Changes in v2:
 - None

 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 2bc29d74e75a..9094690f8258 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 v2 06/12] usb: devicetree: Introduce num-lanes and lsm

[Rob Herring]

On Wed, Jul 22, 2020 at 07:12:39PM -0700, Thinh Nguyen wrote:
> According to USB 3.2 spec, a super-speed-plus device can operate at
> gen2x2, gen2x1, or gen1x2. Introduce "num-lanes" and
> "lane-speed-mantissa-gbps" properties for devices operating in
> super-speed-plus. If the USB controller device supports multiple lanes
> at different transfer rate, the user can specify the HW capability via
> these properties.
> 
> Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
> ---
> Changes in v2:
> - Make "num-lanes" and "lane-speed-mantissa-gbps" common USB properties
> 
>  Documentation/devicetree/bindings/usb/generic.txt | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/usb/generic.txt b/Documentation/devicetree/bindings/usb/generic.txt
> index ba472e7aefc9..a8253da684af 100644
> --- a/Documentation/devicetree/bindings/usb/generic.txt
> +++ b/Documentation/devicetree/bindings/usb/generic.txt
> @@ -7,6 +7,17 @@ Optional properties:
>  			"low-speed". In case this isn't passed via DT, USB
>  			controllers should default to their maximum HW
>  			capability.
> + - num-lanes: tells USB controllers that we want to work up to a certain number
> +			of lanes. Valid arguments are 1 or 2. Apply if the
> +			maximum-speed is super-speed-plus. In case this isn't
> +			passed via DT, the USB controllers should default to
> +			their maximum HW capability.
> + - lane-speed-mantissa-gbps: tells USB controllers that we want the symmetric
> +			lanes to operate up to a certain rate in Gbps. Valid
> +			inputs are 5 or 10 (i.e. Gen 1/Gen 2 transfer rate).
> +			Apply if the maximum-speed is super-speed-plus. In case
> +			this isn't passed via DT, the USB controllers should
> +			default to their maximum HW capability.

This still leaves 'maximum-speed = "super-speed-plus"' ambiguous. Fix 
that please.

To put it another way, we already have one way to define USB speeds. 
Don't define a new and different way that only covers a fraction of the 
possibilities.

Rob

Re: [PATCH v2 06/12] usb: devicetree: Introduce num-lanes and lsm

[Thinh Nguyen]

Rob Herring wrote:
> On Wed, Jul 22, 2020 at 07:12:39PM -0700, Thinh Nguyen wrote:
>> According to USB 3.2 spec, a super-speed-plus device can operate at
>> gen2x2, gen2x1, or gen1x2. Introduce "num-lanes" and
>> "lane-speed-mantissa-gbps" properties for devices operating in
>> super-speed-plus. If the USB controller device supports multiple lanes
>> at different transfer rate, the user can specify the HW capability via
>> these properties.
>>
>> Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
>> ---
>> Changes in v2:
>> - Make "num-lanes" and "lane-speed-mantissa-gbps" common USB properties
>>
>>   Documentation/devicetree/bindings/usb/generic.txt | 11 +++++++++++
>>   1 file changed, 11 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/usb/generic.txt b/Documentation/devicetree/bindings/usb/generic.txt
>> index ba472e7aefc9..a8253da684af 100644
>> --- a/Documentation/devicetree/bindings/usb/generic.txt
>> +++ b/Documentation/devicetree/bindings/usb/generic.txt
>> @@ -7,6 +7,17 @@ Optional properties:
>>   			"low-speed". In case this isn't passed via DT, USB
>>   			controllers should default to their maximum HW
>>   			capability.
>> + - num-lanes: tells USB controllers that we want to work up to a certain number
>> +			of lanes. Valid arguments are 1 or 2. Apply if the
>> +			maximum-speed is super-speed-plus. In case this isn't
>> +			passed via DT, the USB controllers should default to
>> +			their maximum HW capability.
>> + - lane-speed-mantissa-gbps: tells USB controllers that we want the symmetric
>> +			lanes to operate up to a certain rate in Gbps. Valid
>> +			inputs are 5 or 10 (i.e. Gen 1/Gen 2 transfer rate).
>> +			Apply if the maximum-speed is super-speed-plus. In case
>> +			this isn't passed via DT, the USB controllers should
>> +			default to their maximum HW capability.
> This still leaves 'maximum-speed = "super-speed-plus"' ambiguous. Fix
> that please.
>
> To put it another way, we already have one way to define USB speeds.
> Don't define a new and different way that only covers a fraction of the
> possibilities.
>

Then, we can just do away with the "num-lanes" property, and change it 
to something like this as you suggested?

diff --git a/Documentation/devicetree/bindings/usb/generic.txt 
b/Documentation/devicetree/bindings/usb/generic.txt
index ba472e7aefc9..8541b9571f2f 100644
--- a/Documentation/devicetree/bindings/usb/generic.txt
+++ b/Documentation/devicetree/bindings/usb/generic.txt
@@ -3,10 +3,13 @@ Generic USB Properties
  Optional properties:
   - maximum-speed: tells USB controllers we want to work up to a certain
                         speed. Valid arguments are "super-speed-plus",
-                       "super-speed", "high-speed", "full-speed" and
-                       "low-speed". In case this isn't passed via DT, USB
-                       controllers should default to their maximum HW
-                       capability.
+                       "super-speed-plus-gen2x2", 
"super-speed-plus-gen2x1",
+                       "super-speed-plus-gen1x2", "super-speed", 
"high-speed",
+                       "full-speed" and "low-speed". In case this isn't 
passed
+                       via DT, USB controllers should default to their 
maximum
+                       HW capability. Similarly, if the argument is
+                       "super-speed-plus", USB controllers should 
default to
+                       their maximum transfer rate and number of lanes.
   - dr_mode: tells Dual-Role USB controllers that we want to work on a
                         particular mode. Valid arguments are "host",
                         "peripheral" and "otg". In case this attribute 
isn't


Is that ok?

BR,
Thinh