[PATCH v5 09/12] usb: dwc3: gadget: Report sublink speed capability

From: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
To: Felipe Balbi <balbi@kernel.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Thinh.Nguyen@synopsys.com, linux-usb@vger.kernel.org
Cc: John Youn <John.Youn@synopsys.com>
Subject: [PATCH v5 09/12] usb: dwc3: gadget: Report sublink speed capability
Date: Thu, 24 Sep 2020 19:42:38 -0700	[thread overview]
Message-ID: <d7fe65c16eefc53fb7176947e69a902a73bd8c5a.1601001199.git.Thinh.Nguyen@synopsys.com> (raw)
In-Reply-To: <cover.1601001199.git.Thinh.Nguyen@synopsys.com>

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

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

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

Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
---
Changes in v5:
- Rebase on Felipe's testing/next branch
- Changed Signed-off-by email to match From: email header
Changes in v4:
- None
Changes in v3:
- Update commit with updated field name
- No longer use DWC3_LSM_5/10_GBPS macros
Changes in v2:
- Fix missing check for gen1x2 when writing to sublink speed attributes
- Minor fix in commit message (first commit sentence ended with comma)

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

diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 585a83ada270..c4a33545530d 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
 
+/* 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 82bc075ba97c..e60161205bf9 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -3779,6 +3779,55 @@ 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_phy_gen == USB_PHY_GEN_2 &&
+		    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_phy_gen == USB_PHY_GEN_1 &&
+			   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 = 5;
+			else
+				ssa->mantissa = 10;
+
+			/* 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
-- 
2.28.0

