usb/gadget: Add driver for Aspeed SoC virtual hub

The Aspeed BMC SoCs support a "virtual hub" function. It provides some
HW support for a top-level USB2 hub behind which sit 5 gadget "ports".

This driver adds support for the full functionality, emulating the
hub standard requests and exposing 5 UDC gadget drivers corresponding
to the ports.

The hub itself has HW provided dedicated EP0 and EP1 (the latter for
hub interrupts). It also has dedicated EP0s for each function. For
other endpoints, there's a pool of 15 "generic" endpoints that are
shared among the ports.

The driver relies on my previous patch adding a "dispose" EP op to
handle EP allocation between ports. EPs are allocated from the shared
pool in the UDC "match_ep" callback and assigned to the UDC instance
(added to the gadget ep_list).

When the composite driver gets unbound, the new hook will allow the UDC
to clean things up and return those EPs to the shared pool.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

10 files changed, 3700 insertions, 0 deletions

diff --git a/drivers/usb/gadget/udc/Kconfig b/drivers/usb/gadget/udc/Kconfig
index 0875d38476ee..b838caeaaaa1 100644
--- a/drivers/usb/gadget/udc/Kconfig
+++ b/drivers/usb/gadget/udc/Kconfig
@@ -438,6 +438,8 @@ config USB_GADGET_XILINX
 	  dynamically linked module called "udc-xilinx" and force all
 	  gadget drivers to also be dynamically linked.
 
+source "drivers/usb/gadget/udc/aspeed-vhub/Kconfig"
+
 #
 # LAST -- dummy/emulated controller
 #
diff --git a/drivers/usb/gadget/udc/Makefile b/drivers/usb/gadget/udc/Makefile
index ce865b129fd6..897f648f3cf1 100644
--- a/drivers/usb/gadget/udc/Makefile
+++ b/drivers/usb/gadget/udc/Makefile
@@ -39,4 +39,5 @@ obj-$(CONFIG_USB_MV_U3D)	+= mv_u3d_core.o
 obj-$(CONFIG_USB_GR_UDC)	+= gr_udc.o
 obj-$(CONFIG_USB_GADGET_XILINX)	+= udc-xilinx.o
 obj-$(CONFIG_USB_SNP_UDC_PLAT) += snps_udc_plat.o
+obj-$(CONFIG_USB_ASPEED_VHUB)	+= aspeed-vhub/
 obj-$(CONFIG_USB_BDC_UDC)	+= bdc/
diff --git a/drivers/usb/gadget/udc/aspeed-vhub/Kconfig b/drivers/usb/gadget/udc/aspeed-vhub/Kconfig
new file mode 100644
index 000000000000..f0cdf89b8503
--- /dev/null
+++ b/drivers/usb/gadget/udc/aspeed-vhub/Kconfig
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0+
+config USB_ASPEED_VHUB
+	tristate "Aspeed vHub UDC driver"
+	depends on ARCH_ASPEED || COMPILE_TEST
+	help
+	  USB peripheral controller for the Aspeed AST2500 family
+	  SoCs supporting the "vHub" functionality and USB2.0
diff --git a/drivers/usb/gadget/udc/aspeed-vhub/Makefile b/drivers/usb/gadget/udc/aspeed-vhub/Makefile
new file mode 100644
index 000000000000..9f3add605f8e
--- /dev/null
+++ b/drivers/usb/gadget/udc/aspeed-vhub/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0+
+obj-$(CONFIG_USB_ASPEED_VHUB)	+= aspeed-vhub.o
+aspeed-vhub-y	:= core.o ep0.o epn.o dev.o hub.o
+
diff --git a/drivers/usb/gadget/udc/aspeed-vhub/core.c b/drivers/usb/gadget/udc/aspeed-vhub/core.c
new file mode 100644
index 000000000000..db3628be38c0
--- /dev/null
+++ b/drivers/usb/gadget/udc/aspeed-vhub/core.c
@@ -0,0 +1,425 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * aspeed-vhub -- Driver for Aspeed SoC "vHub" USB gadget
+ *
+ * core.c - Top level support
+ *
+ * Copyright 2017 IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/ioport.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include <linux/list.h>
+#include <linux/interrupt.h>
+#include <linux/proc_fs.h>
+#include <linux/prefetch.h>
+#include <linux/clk.h>
+#include <linux/usb/gadget.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/regmap.h>
+#include <linux/dma-mapping.h>
+
+#include "vhub.h"
+
+void ast_vhub_done(struct ast_vhub_ep *ep, struct ast_vhub_req *req,
+		   int status)
+{
+	bool internal = req->internal;
+
+	EPVDBG(ep, "completing request @%p, status %d\n", req, status);
+
+	list_del_init(&req->queue);
+
+	if (req->req.status == -EINPROGRESS)
+		req->req.status = status;
+
+	if (req->req.dma) {
+		if (!WARN_ON(!ep->dev))
+			usb_gadget_unmap_request(&ep->dev->gadget,
+						 &req->req, ep->epn.is_in);
+		req->req.dma = 0;
+	}
+
+	/*
+	 * If this isn't an internal EP0 request, call the core
+	 * to call the gadget completion.
+	 */
+	if (!internal) {
+		spin_unlock(&ep->vhub->lock);
+		usb_gadget_giveback_request(&ep->ep, &req->req);
+		spin_lock(&ep->vhub->lock);
+	}
+}
+
+void ast_vhub_nuke(struct ast_vhub_ep *ep, int status)
+{
+	struct ast_vhub_req *req;
+
+	EPDBG(ep, "Nuking\n");
+
+	/* Beware, lock will be dropped & req-acquired by done() */
+	while (!list_empty(&ep->queue)) {
+		req = list_first_entry(&ep->queue, struct ast_vhub_req, queue);
+		ast_vhub_done(ep, req, status);
+	}
+}
+
+struct usb_request *ast_vhub_alloc_request(struct usb_ep *u_ep,
+					   gfp_t gfp_flags)
+{
+	struct ast_vhub_req *req;
+
+	req = kzalloc(sizeof(*req), gfp_flags);
+	if (!req)
+		return NULL;
+	return &req->req;
+}
+
+void ast_vhub_free_request(struct usb_ep *u_ep, struct usb_request *u_req)
+{
+	struct ast_vhub_req *req = to_ast_req(u_req);
+
+	kfree(req);
+}
+
+static irqreturn_t ast_vhub_irq(int irq, void *data)
+{
+	struct ast_vhub *vhub = data;
+	irqreturn_t iret = IRQ_NONE;
+	u32 istat;
+
+	/* Stale interrupt while tearing down */
+	if (!vhub->ep0_bufs)
+		return IRQ_NONE;
+
+	spin_lock(&vhub->lock);
+
+	/* Read and ACK interrupts */
+	istat = readl(vhub->regs + AST_VHUB_ISR);
+	if (!istat)
+		goto bail;
+	writel(istat, vhub->regs + AST_VHUB_ISR);
+	iret = IRQ_HANDLED;
+
+	UDCVDBG(vhub, "irq status=%08x, ep_acks=%08x ep_nacks=%08x\n",
+	       istat,
+	       readl(vhub->regs + AST_VHUB_EP_ACK_ISR),
+	       readl(vhub->regs + AST_VHUB_EP_NACK_ISR));
+
+	/* Handle generic EPs first */
+	if (istat & VHUB_IRQ_EP_POOL_ACK_STALL) {
+		u32 i, ep_acks = readl(vhub->regs + AST_VHUB_EP_ACK_ISR);
+		writel(ep_acks, vhub->regs + AST_VHUB_EP_ACK_ISR);
+
+		for (i = 0; ep_acks && i < AST_VHUB_NUM_GEN_EPs; i++) {
+			u32 mask = VHUB_EP_IRQ(i);
+			if (ep_acks & mask) {
+				ast_vhub_epn_ack_irq(&vhub->epns[i]);
+				ep_acks &= ~mask;
+			}
+		}
+	}
+
+	/* Handle device interrupts */
+	if (istat & (VHUB_IRQ_DEVICE1 |
+		     VHUB_IRQ_DEVICE2 |
+		     VHUB_IRQ_DEVICE3 |
+		     VHUB_IRQ_DEVICE4 |
+		     VHUB_IRQ_DEVICE5)) {
+		if (istat & VHUB_IRQ_DEVICE1)
+			ast_vhub_dev_irq(&vhub->ports[0].dev);
+		if (istat & VHUB_IRQ_DEVICE2)
+			ast_vhub_dev_irq(&vhub->ports[1].dev);
+		if (istat & VHUB_IRQ_DEVICE3)
+			ast_vhub_dev_irq(&vhub->ports[2].dev);
+		if (istat & VHUB_IRQ_DEVICE4)
+			ast_vhub_dev_irq(&vhub->ports[3].dev);
+		if (istat & VHUB_IRQ_DEVICE5)
+			ast_vhub_dev_irq(&vhub->ports[4].dev);
+	}
+
+	/* Handle top-level vHub EP0 interrupts */
+	if (istat & (VHUB_IRQ_HUB_EP0_OUT_ACK_STALL |
+		     VHUB_IRQ_HUB_EP0_IN_ACK_STALL |
+		     VHUB_IRQ_HUB_EP0_SETUP)) {
+		if (istat & VHUB_IRQ_HUB_EP0_IN_ACK_STALL)
+			ast_vhub_ep0_handle_ack(&vhub->ep0, true);
+		if (istat & VHUB_IRQ_HUB_EP0_OUT_ACK_STALL)
+			ast_vhub_ep0_handle_ack(&vhub->ep0, false);
+		if (istat & VHUB_IRQ_HUB_EP0_SETUP)
+			ast_vhub_ep0_handle_setup(&vhub->ep0);
+	}
+
+	/* Various top level bus events */
+	if (istat & (VHUB_IRQ_BUS_RESUME |
+		     VHUB_IRQ_BUS_SUSPEND |
+		     VHUB_IRQ_BUS_RESET)) {
+		if (istat & VHUB_IRQ_BUS_RESUME)
+			ast_vhub_hub_resume(vhub);
+		if (istat & VHUB_IRQ_BUS_SUSPEND)
+			ast_vhub_hub_suspend(vhub);
+		if (istat & VHUB_IRQ_BUS_RESET)
+			ast_vhub_hub_reset(vhub);
+	}
+
+ bail:
+	spin_unlock(&vhub->lock);
+	return iret;
+}
+
+void ast_vhub_init_hw(struct ast_vhub *vhub)
+{
+	u32 ctrl;
+
+	UDCDBG(vhub,"(Re)Starting HW ...\n");
+
+	/* Enable PHY */
+	ctrl = VHUB_CTRL_PHY_CLK |
+		VHUB_CTRL_PHY_RESET_DIS;
+
+       /*
+	* We do *NOT* set the VHUB_CTRL_CLK_STOP_SUSPEND bit
+	* to stop the logic clock during suspend because
+	* it causes the registers to become inaccessible and
+	* we haven't yet figured out a good wayt to bring the
+	* controller back into life to issue a wakeup.
+	*/
+
+	/*
+	 * Set some ISO & split control bits according to Aspeed
+	 * recommendation
+	 *
+	 * VHUB_CTRL_ISO_RSP_CTRL: When set tells the HW to respond
+	 * with 0 bytes data packet to ISO IN endpoints when no data
+	 * is available.
+	 *
+	 * VHUB_CTRL_SPLIT_IN: This makes a SOF complete a split IN
+	 * transaction.
+	 */
+	ctrl |= VHUB_CTRL_ISO_RSP_CTRL | VHUB_CTRL_SPLIT_IN;
+	writel(ctrl, vhub->regs + AST_VHUB_CTRL);
+	udelay(1);
+
+	/* Set descriptor ring size */
+	if (AST_VHUB_DESCS_COUNT == 256) {
+		ctrl |= VHUB_CTRL_LONG_DESC;
+		writel(ctrl, vhub->regs + AST_VHUB_CTRL);
+	} else {
+		BUILD_BUG_ON(AST_VHUB_DESCS_COUNT != 32);
+	}
+
+	/* Reset all devices */
+	writel(VHUB_SW_RESET_ALL, vhub->regs + AST_VHUB_SW_RESET);
+	udelay(1);
+	writel(0, vhub->regs + AST_VHUB_SW_RESET);
+
+	/* Disable and cleanup EP ACK/NACK interrupts */
+	writel(0, vhub->regs + AST_VHUB_EP_ACK_IER);
+	writel(0, vhub->regs + AST_VHUB_EP_NACK_IER);
+	writel(VHUB_EP_IRQ_ALL, vhub->regs + AST_VHUB_EP_ACK_ISR);
+	writel(VHUB_EP_IRQ_ALL, vhub->regs + AST_VHUB_EP_NACK_ISR);
+
+	/* Default settings for EP0, enable HW hub EP1 */
+	writel(0, vhub->regs + AST_VHUB_EP0_CTRL);
+	writel(VHUB_EP1_CTRL_RESET_TOGGLE |
+	       VHUB_EP1_CTRL_ENABLE,
+	       vhub->regs + AST_VHUB_EP1_CTRL);
+	writel(0, vhub->regs + AST_VHUB_EP1_STS_CHG);
+
+	/* Configure EP0 DMA buffer */
+	writel(vhub->ep0.buf_dma, vhub->regs + AST_VHUB_EP0_DATA);
+
+	/* Clear address */
+	writel(0, vhub->regs + AST_VHUB_CONF);
+
+	/* Pullup hub (activate on host) */
+	if (vhub->force_usb1)
+		ctrl |= VHUB_CTRL_FULL_SPEED_ONLY;
+
+	ctrl |= VHUB_CTRL_UPSTREAM_CONNECT;
+	writel(ctrl, vhub->regs + AST_VHUB_CTRL);
+
+	/* Enable some interrupts */
+	writel(VHUB_IRQ_HUB_EP0_IN_ACK_STALL |
+	       VHUB_IRQ_HUB_EP0_OUT_ACK_STALL |
+	       VHUB_IRQ_HUB_EP0_SETUP |
+	       VHUB_IRQ_EP_POOL_ACK_STALL |
+	       VHUB_IRQ_BUS_RESUME |
+	       VHUB_IRQ_BUS_SUSPEND |
+	       VHUB_IRQ_BUS_RESET,
+	       vhub->regs + AST_VHUB_IER);
+}
+
+static int ast_vhub_remove(struct platform_device *pdev)
+{
+	struct ast_vhub *vhub = platform_get_drvdata(pdev);
+	unsigned long flags;
+	int i;
+
+	if (!vhub || !vhub->regs)
+		return 0;
+
+	/* Remove devices */
+	for (i = 0; i < AST_VHUB_NUM_PORTS; i++)
+		ast_vhub_del_dev(&vhub->ports[i].dev);
+
+	spin_lock_irqsave(&vhub->lock, flags);
+
+	/* Mask & ack all interrupts  */
+	writel(0, vhub->regs + AST_VHUB_IER);
+	writel(VHUB_IRQ_ACK_ALL, vhub->regs + AST_VHUB_ISR);
+
+	/* Pull device, leave PHY enabled */
+	writel(VHUB_CTRL_PHY_CLK |
+	       VHUB_CTRL_PHY_RESET_DIS,
+	       vhub->regs + AST_VHUB_CTRL);
+
+	if (vhub->clk)
+		clk_disable_unprepare(vhub->clk);
+
+	spin_unlock_irqrestore(&vhub->lock, flags);
+
+	if (vhub->ep0_bufs)
+		dma_free_coherent(&pdev->dev,
+				  AST_VHUB_EP0_MAX_PACKET *
+				  (AST_VHUB_NUM_PORTS + 1),
+				  vhub->ep0_bufs,
+				  vhub->ep0_bufs_dma);
+	vhub->ep0_bufs = NULL;
+
+	return 0;
+}
+
+static int ast_vhub_probe(struct platform_device *pdev)
+{
+	enum usb_device_speed max_speed;
+	struct ast_vhub *vhub;
+	struct resource *res;
+	int i, rc = 0;
+
+	vhub = devm_kzalloc(&pdev->dev, sizeof(*vhub), GFP_KERNEL);
+	if (!vhub)
+		return -ENOMEM;
+
+	spin_lock_init(&vhub->lock);
+	vhub->pdev = pdev;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	vhub->regs = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(vhub->regs)) {
+		dev_err(&pdev->dev, "Failed to map resources\n");
+		return PTR_ERR(vhub->regs);
+	}
+	UDCDBG(vhub, "vHub@%pR mapped @%p\n", res, vhub->regs);
+
+	platform_set_drvdata(pdev, vhub);
+
+	vhub->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(vhub->clk)) {
+		rc = PTR_ERR(vhub->clk);
+		goto err;
+	}
+	rc = clk_prepare_enable(vhub->clk);
+	if (rc) {
+		dev_err(&pdev->dev, "Error couldn't enable clock (%d)\n", rc);
+		goto err;
+	}
+
+	/* Check if we need to limit the HW to USB1 */
+	max_speed = usb_get_maximum_speed(&pdev->dev);
+	if (max_speed != USB_SPEED_UNKNOWN && max_speed < USB_SPEED_HIGH)
+		vhub->force_usb1 = true;
+
+	/* Mask & ack all interrupts before installing the handler */
+	writel(0, vhub->regs + AST_VHUB_IER);
+	writel(VHUB_IRQ_ACK_ALL, vhub->regs + AST_VHUB_ISR);
+
+	/* Find interrupt and install handler */
+	vhub->irq = platform_get_irq(pdev, 0);
+	if (vhub->irq < 0) {
+		dev_err(&pdev->dev, "Failed to get interrupt\n");
+		rc = vhub->irq;
+		goto err;
+	}
+	rc = devm_request_irq(&pdev->dev, vhub->irq, ast_vhub_irq, 0,
+			      KBUILD_MODNAME, vhub);
+	if (rc) {
+		dev_err(&pdev->dev, "Failed to request interrupt\n");
+		goto err;
+	}
+
+	/*
+	 * Allocate DMA buffers for all EP0s in one chunk,
+	 * one per port and one for the vHub itself
+	 */
+	vhub->ep0_bufs = dma_alloc_coherent(&pdev->dev,
+					    AST_VHUB_EP0_MAX_PACKET *
+					    (AST_VHUB_NUM_PORTS + 1),
+					    &vhub->ep0_bufs_dma, GFP_KERNEL);
+	if (!vhub->ep0_bufs) {
+		dev_err(&pdev->dev, "Failed to allocate EP0 DMA buffers\n");
+		rc = -ENOMEM;
+		goto err;
+	}
+	UDCVDBG(vhub, "EP0 DMA buffers @%p (DMA 0x%08x)\n",
+		vhub->ep0_bufs, (u32)vhub->ep0_bufs_dma);
+
+	/* Init vHub EP0 */
+	ast_vhub_init_ep0(vhub, &vhub->ep0, NULL);
+
+	/* Init devices */
+	for (i = 0; i < AST_VHUB_NUM_PORTS && rc == 0; i++)
+		rc = ast_vhub_init_dev(vhub, i);
+	if (rc)
+		goto err;
+
+	/* Init hub emulation */
+	ast_vhub_init_hub(vhub);
+
+	/* Initialize HW */
+	ast_vhub_init_hw(vhub);
+
+	dev_info(&pdev->dev, "Initialized virtual hub in USB%d mode\n",
+		 vhub->force_usb1 ? 1 : 2);
+
+	return 0;
+ err:
+	ast_vhub_remove(pdev);
+	return rc;
+}
+
+static const struct of_device_id ast_vhub_dt_ids[] = {
+	{
+		.compatible = "aspeed,ast2400-usb-vhub",
+	},
+	{
+		.compatible = "aspeed,ast2500-usb-vhub",
+	},
+	{ }
+};
+MODULE_DEVICE_TABLE(of, ast_vhub_dt_ids);
+
+static struct platform_driver ast_vhub_driver = {
+	.probe		= ast_vhub_probe,
+	.remove		= ast_vhub_remove,
+	.driver		= {
+		.name	= KBUILD_MODNAME,
+		.of_match_table	= ast_vhub_dt_ids,
+	},
+};
+module_platform_driver(ast_vhub_driver);
+
+MODULE_DESCRIPTION("Aspeed vHub udc driver");
+MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/usb/gadget/udc/aspeed-vhub/dev.c b/drivers/usb/gadget/udc/aspeed-vhub/dev.c
new file mode 100644
index 000000000000..f0233912bace
--- /dev/null
+++ b/drivers/usb/gadget/udc/aspeed-vhub/dev.c
@@ -0,0 +1,589 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * aspeed-vhub -- Driver for Aspeed SoC "vHub" USB gadget
+ *
+ * dev.c - Individual device/gadget management (ie, a port = a gadget)
+ *
+ * Copyright 2017 IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/ioport.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include <linux/list.h>
+#include <linux/interrupt.h>
+#include <linux/proc_fs.h>
+#include <linux/prefetch.h>
+#include <linux/clk.h>
+#include <linux/usb/gadget.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/regmap.h>
+#include <linux/dma-mapping.h>
+#include <linux/usb.h>
+#include <linux/usb/hcd.h>
+
+#include "vhub.h"
+
+void ast_vhub_dev_irq(struct ast_vhub_dev *d)
+{
+	u32 istat = readl(d->regs + AST_VHUB_DEV_ISR);
+
+	writel(istat, d->regs + AST_VHUB_DEV_ISR);
+
+	if (istat & VHUV_DEV_IRQ_EP0_IN_ACK_STALL)
+		ast_vhub_ep0_handle_ack(&d->ep0, true);
+	if (istat & VHUV_DEV_IRQ_EP0_OUT_ACK_STALL)
+		ast_vhub_ep0_handle_ack(&d->ep0, false);
+	if (istat & VHUV_DEV_IRQ_EP0_SETUP)
+		ast_vhub_ep0_handle_setup(&d->ep0);
+}
+
+static void ast_vhub_dev_enable(struct ast_vhub_dev *d)
+{
+	u32 reg, hmsk;
+
+	if (d->enabled)
+		return;
+
+	/* Enable device and its EP0 interrupts */
+	reg = VHUB_DEV_EN_ENABLE_PORT |
+		VHUB_DEV_EN_EP0_IN_ACK_IRQEN |
+		VHUB_DEV_EN_EP0_OUT_ACK_IRQEN |
+		VHUB_DEV_EN_EP0_SETUP_IRQEN;
+	if (d->gadget.speed == USB_SPEED_HIGH)
+		reg |= VHUB_DEV_EN_SPEED_SEL_HIGH;
+	writel(reg, d->regs + AST_VHUB_DEV_EN_CTRL);
+
+	/* Enable device interrupt in the hub as well */
+	hmsk = VHUB_IRQ_DEVICE1 << d->index;
+	reg = readl(d->vhub->regs + AST_VHUB_IER);
+	reg |= hmsk;
+	writel(reg, d->vhub->regs + AST_VHUB_IER);
+
+	/* Set EP0 DMA buffer address */
+	writel(d->ep0.buf_dma, d->regs + AST_VHUB_DEV_EP0_DATA);
+
+	d->enabled = true;
+}
+
+static void ast_vhub_dev_disable(struct ast_vhub_dev *d)
+{
+	u32 reg, hmsk;
+
+	if (!d->enabled)
+		return;
+
+	/* Disable device interrupt in the hub */
+	hmsk = VHUB_IRQ_DEVICE1 << d->index;
+	reg = readl(d->vhub->regs + AST_VHUB_IER);
+	reg &= ~hmsk;
+	writel(reg, d->vhub->regs + AST_VHUB_IER);
+
+	/* Then disable device */
+	writel(0, d->regs + AST_VHUB_DEV_EN_CTRL);
+	d->gadget.speed = USB_SPEED_UNKNOWN;
+	d->enabled = false;
+	d->suspended = false;
+}
+
+static int ast_vhub_dev_feature(struct ast_vhub_dev *d,
+				u16 wIndex, u16 wValue,
+				bool is_set)
+{
+	DDBG(d, "%s_FEATURE(dev val=%02x)\n",
+	     is_set ? "SET" : "CLEAR", wValue);
+
+	if (wValue != USB_DEVICE_REMOTE_WAKEUP)
+		return std_req_driver;
+
+	d->wakeup_en = is_set;
+
+	return std_req_complete;
+}
+
+static int ast_vhub_ep_feature(struct ast_vhub_dev *d,
+			       u16 wIndex, u16 wValue, bool is_set)
+{
+	struct ast_vhub_ep *ep;
+	int ep_num;
+
+	ep_num = wIndex & USB_ENDPOINT_NUMBER_MASK;
+	DDBG(d, "%s_FEATURE(ep%d val=%02x)\n",
+	     is_set ? "SET" : "CLEAR", ep_num, wValue);
+	if (ep_num == 0)
+		return std_req_complete;
+	if (ep_num >= AST_VHUB_NUM_GEN_EPs || !d->epns[ep_num - 1])
+		return std_req_stall;
+	if (wValue != USB_ENDPOINT_HALT)
+		return std_req_driver;
+
+	ep = d->epns[ep_num - 1];
+	if (WARN_ON(!ep))
+		return std_req_stall;
+
+	if (!ep->epn.enabled || !ep->ep.desc || ep->epn.is_iso ||
+	    ep->epn.is_in != !!(wIndex & USB_DIR_IN))
+		return std_req_stall;
+
+	DDBG(d, "%s stall on EP %d\n",
+	     is_set ? "setting" : "clearing", ep_num);
+	ep->epn.stalled = is_set;
+	ast_vhub_update_epn_stall(ep);
+
+	return std_req_complete;
+}
+
+static int ast_vhub_dev_status(struct ast_vhub_dev *d,
+			       u16 wIndex, u16 wValue)
+{
+	u8 st0;
+
+	DDBG(d, "GET_STATUS(dev)\n");
+
+	st0 = d->gadget.is_selfpowered << USB_DEVICE_SELF_POWERED;
+	if (d->wakeup_en)
+		st0 |= 1 << USB_DEVICE_REMOTE_WAKEUP;
+
+	return ast_vhub_simple_reply(&d->ep0, st0, 0);
+}
+
+static int ast_vhub_ep_status(struct ast_vhub_dev *d,
+			      u16 wIndex, u16 wValue)
+{
+	int ep_num = wIndex & USB_ENDPOINT_NUMBER_MASK;
+	struct ast_vhub_ep *ep;
+	u8 st0 = 0;
+
+	DDBG(d, "GET_STATUS(ep%d)\n", ep_num);
+
+	if (ep_num >= AST_VHUB_NUM_GEN_EPs)
+		return std_req_stall;
+	if (ep_num != 0) {
+		ep = d->epns[ep_num - 1];
+		if (!ep)
+			return std_req_stall;
+		if (!ep->epn.enabled || !ep->ep.desc || ep->epn.is_iso ||
+		    ep->epn.is_in != !!(wIndex & USB_DIR_IN))
+			return std_req_stall;
+		if (ep->epn.stalled)
+			st0 |= 1 << USB_ENDPOINT_HALT;
+	}
+
+	return ast_vhub_simple_reply(&d->ep0, st0, 0);
+}
+
+static void ast_vhub_dev_set_address(struct ast_vhub_dev *d, u8 addr)
+{
+	u32 reg;
+
+	DDBG(d, "SET_ADDRESS: Got address %x\n", addr);
+
+	reg = readl(d->regs + AST_VHUB_DEV_EN_CTRL);
+	reg &= ~VHUB_DEV_EN_ADDR_MASK;
+	reg |= VHUB_DEV_EN_SET_ADDR(addr);
+	writel(reg, d->regs + AST_VHUB_DEV_EN_CTRL);
+}
+
+int ast_vhub_std_dev_request(struct ast_vhub_ep *ep,
+			     struct usb_ctrlrequest *crq)
+{
+	struct ast_vhub_dev *d = ep->dev;
+	u16 wValue, wIndex;
+
+	/* No driver, we shouldn't be enabled ... */
+	if (!d->driver || !d->enabled || d->suspended) {
+		EPDBG(ep,
+		      "Device is wrong state driver=%p enabled=%d"
+		      " suspended=%d\n",
+		      d->driver, d->enabled, d->suspended);
+		return std_req_stall;
+	}
+
+	/* First packet, grab speed */
+	if (d->gadget.speed == USB_SPEED_UNKNOWN) {
+		d->gadget.speed = ep->vhub->speed;
+		if (d->gadget.speed > d->driver->max_speed)
+			d->gadget.speed = d->driver->max_speed;
+		DDBG(d, "fist packet, captured speed %d\n",
+		     d->gadget.speed);
+	}
+
+	wValue = le16_to_cpu(crq->wValue);
+	wIndex = le16_to_cpu(crq->wIndex);
+
+	switch ((crq->bRequestType << 8) | crq->bRequest) {
+		/* SET_ADDRESS */
+	case DeviceOutRequest | USB_REQ_SET_ADDRESS:
+		ast_vhub_dev_set_address(d, wValue);
+		return std_req_complete;
+
+		/* GET_STATUS */
+	case DeviceRequest | USB_REQ_GET_STATUS:
+		return ast_vhub_dev_status(d, wIndex, wValue);
+	case InterfaceRequest | USB_REQ_GET_STATUS:
+		return ast_vhub_simple_reply(ep, 0, 0);
+	case EndpointRequest | USB_REQ_GET_STATUS:
+		return ast_vhub_ep_status(d, wIndex, wValue);
+
+		/* SET/CLEAR_FEATURE */
+	case DeviceOutRequest | USB_REQ_SET_FEATURE:
+		return ast_vhub_dev_feature(d, wIndex, wValue, true);
+	case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
+		return ast_vhub_dev_feature(d, wIndex, wValue, false);
+	case EndpointOutRequest | USB_REQ_SET_FEATURE:
+		return ast_vhub_ep_feature(d, wIndex, wValue, true);
+	case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
+		return ast_vhub_ep_feature(d, wIndex, wValue, false);
+	}
+	return std_req_driver;
+}
+
+static int ast_vhub_udc_wakeup(struct usb_gadget* gadget)
+{
+	struct ast_vhub_dev *d = to_ast_dev(gadget);
+	unsigned long flags;
+	int rc = -EINVAL;
+
+	spin_lock_irqsave(&d->vhub->lock, flags);
+	if (!d->wakeup_en)
+		goto err;
+
+	DDBG(d, "Device initiated wakeup\n");
+
+	/* Wakeup the host */
+	ast_vhub_hub_wake_all(d->vhub);
+	rc = 0;
+ err:
+	spin_unlock_irqrestore(&d->vhub->lock, flags);
+	return rc;
+}
+
+static int ast_vhub_udc_get_frame(struct usb_gadget* gadget)
+{
+	struct ast_vhub_dev *d = to_ast_dev(gadget);
+
+	return (readl(d->vhub->regs + AST_VHUB_USBSTS) >> 16) & 0x7ff;
+}
+
+static void ast_vhub_dev_nuke(struct ast_vhub_dev *d)
+{
+	unsigned int i;
+
+	for (i = 0; i < AST_VHUB_NUM_GEN_EPs; i++) {
+		if (!d->epns[i])
+			continue;
+		ast_vhub_nuke(d->epns[i], -ESHUTDOWN);
+	}
+}
+
+static int ast_vhub_udc_pullup(struct usb_gadget* gadget, int on)
+{
+	struct ast_vhub_dev *d = to_ast_dev(gadget);
+	unsigned long flags;
+
+	spin_lock_irqsave(&d->vhub->lock, flags);
+
+	DDBG(d, "pullup(%d)\n", on);
+
+	/* Mark disconnected in the hub */
+	ast_vhub_device_connect(d->vhub, d->index, on);
+
+	/*
+	 * If enabled, nuke all requests if any (there shouldn't be)
+	 * and disable the port. This will clear the address too.
+	 */
+	if (d->enabled) {
+		ast_vhub_dev_nuke(d);
+		ast_vhub_dev_disable(d);
+	}
+
+	spin_unlock_irqrestore(&d->vhub->lock, flags);
+
+	return 0;
+}
+
+static int ast_vhub_udc_start(struct usb_gadget *gadget,
+			      struct usb_gadget_driver *driver)
+{
+	struct ast_vhub_dev *d = to_ast_dev(gadget);
+	unsigned long flags;
+
+	spin_lock_irqsave(&d->vhub->lock, flags);
+
+	DDBG(d, "start\n");
+
+	/* We don't do much more until the hub enables us */
+	d->driver = driver;
+	d->gadget.is_selfpowered = 1;
+
+	spin_unlock_irqrestore(&d->vhub->lock, flags);
+
+	return 0;
+}
+
+static struct usb_ep *ast_vhub_udc_match_ep(struct usb_gadget *gadget,
+					    struct usb_endpoint_descriptor *desc,
+					    struct usb_ss_ep_comp_descriptor *ss)
+{
+	struct ast_vhub_dev *d = to_ast_dev(gadget);
+	struct ast_vhub_ep *ep;
+	struct usb_ep *u_ep;
+	unsigned int max, addr, i;
+
+	DDBG(d, "Match EP type %d\n", usb_endpoint_type(desc));
+
+	/*
+	 * First we need to look for an existing unclaimed EP as another
+	 * configuration may have already associated a bunch of EPs with
+	 * this gadget. This duplicates the code in usb_ep_autoconfig_ss()
+	 * unfortunately.
+	 */
+	list_for_each_entry(u_ep, &gadget->ep_list, ep_list) {
+		if (usb_gadget_ep_match_desc(gadget, u_ep, desc, ss)) {
+			DDBG(d, " -> using existing EP%d\n",
+			     to_ast_ep(u_ep)->d_idx);
+			return u_ep;
+		}
+	}
+
+	/*
+	 * We didn't find one, we need to grab one from the pool.
+	 *
+	 * First let's do some sanity checking
+	 */
+	switch(usb_endpoint_type(desc)) {
+	case USB_ENDPOINT_XFER_CONTROL:
+		/* Only EP0 can be a control endpoint */
+		return NULL;
+	case USB_ENDPOINT_XFER_ISOC:
+		/* ISO:	 limit 1023 bytes full speed, 1024 high/super speed */
+		if (gadget_is_dualspeed(gadget))
+			max = 1024;
+		else
+			max = 1023;
+		break;
+	case USB_ENDPOINT_XFER_BULK:
+		if (gadget_is_dualspeed(gadget))
+			max = 512;
+		else
+			max = 64;
+		break;
+	case USB_ENDPOINT_XFER_INT:
+		if (gadget_is_dualspeed(gadget))
+			max = 1024;
+		else
+			max = 64;
+		break;
+	}
+	if (usb_endpoint_maxp(desc) > max)
+		return NULL;
+
+	/*
+	 * Find a free EP address for that device. We can't
+	 * let the generic code assign these as it would
+	 * create overlapping numbers for IN and OUT which
+	 * we don't support, so also create a suitable name
+	 * that will allow the generic code to use our
+	 * assigned address.
+	 */
+	for (i = 0; i < AST_VHUB_NUM_GEN_EPs; i++)
+		if (d->epns[i] == NULL)
+			break;
+	if (i >= AST_VHUB_NUM_GEN_EPs)
+		return NULL;
+	addr = i + 1;
+
+	/*
+	 * Now grab an EP from the shared pool and associate
+	 * it with our device
+	 */
+	ep = ast_vhub_alloc_epn(d, addr);
+	if (!ep)
+		return NULL;
+	DDBG(d, "Allocated epn#%d for port EP%d\n",
+	     ep->epn.g_idx, addr);
+
+	return &ep->ep;
+}
+
+static int ast_vhub_udc_stop(struct usb_gadget *gadget)
+{
+	struct ast_vhub_dev *d = to_ast_dev(gadget);
+	unsigned long flags;
+
+	spin_lock_irqsave(&d->vhub->lock, flags);
+
+	DDBG(d, "stop\n");
+
+	d->driver = NULL;
+	d->gadget.speed = USB_SPEED_UNKNOWN;
+
+	ast_vhub_dev_nuke(d);
+
+	if (d->enabled)
+		ast_vhub_dev_disable(d);
+
+	spin_unlock_irqrestore(&d->vhub->lock, flags);
+
+	return 0;
+}
+
+static struct usb_gadget_ops ast_vhub_udc_ops = {
+	.get_frame	= ast_vhub_udc_get_frame,
+	.wakeup		= ast_vhub_udc_wakeup,
+	.pullup		= ast_vhub_udc_pullup,
+	.udc_start	= ast_vhub_udc_start,
+	.udc_stop	= ast_vhub_udc_stop,
+	.match_ep	= ast_vhub_udc_match_ep,
+};
+
+void ast_vhub_dev_suspend(struct ast_vhub_dev *d)
+{
+	d->suspended = true;
+	if (d->driver) {
+		spin_unlock(&d->vhub->lock);
+		d->driver->suspend(&d->gadget);
+		spin_lock(&d->vhub->lock);
+	}
+}
+
+void ast_vhub_dev_resume(struct ast_vhub_dev *d)
+{
+	d->suspended = false;
+	if (d->driver) {
+		spin_unlock(&d->vhub->lock);
+		d->driver->resume(&d->gadget);
+		spin_lock(&d->vhub->lock);
+	}
+}
+
+void ast_vhub_dev_reset(struct ast_vhub_dev *d)
+{
+	/*
+	 * If speed is not set, we enable the port. If it is,
+	 * send reset to the gadget and reset "speed".
+	 *
+	 * Speed is an indication that we have got the first
+	 * setup packet to the device.
+	 */
+	if (d->gadget.speed == USB_SPEED_UNKNOWN && !d->enabled) {
+		DDBG(d, "Reset at unknown speed of disabled device, enabling...\n");
+		ast_vhub_dev_enable(d);
+		d->suspended = false;
+	}
+	if (d->gadget.speed != USB_SPEED_UNKNOWN && d->driver) {
+		unsigned int i;
+
+		DDBG(d, "Reset at known speed of bound device, resetting...\n");
+		spin_unlock(&d->vhub->lock);
+		d->driver->reset(&d->gadget);
+		spin_lock(&d->vhub->lock);
+
+		/*
+		 * Disable/re-enable HW, this will clear the address
+		 * and speed setting.
+		 */
+		ast_vhub_dev_disable(d);
+		ast_vhub_dev_enable(d);
+
+		/* Clear stall on all EPs */
+		for (i = 0; i < AST_VHUB_NUM_GEN_EPs; i++) {
+			struct ast_vhub_ep *ep = d->epns[i];
+
+			if (ep && ep->epn.stalled) {
+				ep->epn.stalled = false;
+				ast_vhub_update_epn_stall(ep);
+			}
+		}
+
+		/* Additional cleanups */
+		d->wakeup_en = false;
+		d->suspended = false;
+	}
+}
+
+void ast_vhub_del_dev(struct ast_vhub_dev *d)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&d->vhub->lock, flags);
+	if (!d->registered) {
+		spin_unlock_irqrestore(&d->vhub->lock, flags);
+		return;
+	}
+	d->registered = false;
+	spin_unlock_irqrestore(&d->vhub->lock, flags);
+
+	usb_del_gadget_udc(&d->gadget);
+	device_unregister(d->port_dev);
+}
+
+static void ast_vhub_dev_release(struct device *dev)
+{
+	kfree(dev);
+}
+
+int ast_vhub_init_dev(struct ast_vhub *vhub, unsigned int idx)
+{
+	struct ast_vhub_dev *d = &vhub->ports[idx].dev;
+	struct device *parent = &vhub->pdev->dev;
+	int rc;
+
+	d->vhub = vhub;
+	d->index = idx;
+	d->name = devm_kasprintf(parent, GFP_KERNEL, "port%d", idx+1);
+	d->regs = vhub->regs + 0x100 + 0x10 * idx;
+
+	ast_vhub_init_ep0(vhub, &d->ep0, d);
+
+	/*
+	 * The UDC core really needs us to have separate and uniquely
+	 * named "parent" devices for each port so we create a sub device
+	 * here for that purpose
+	 */
+	d->port_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
+	if (!d->port_dev)
+		return -ENOMEM;
+	device_initialize(d->port_dev);
+	d->port_dev->release = ast_vhub_dev_release;
+	d->port_dev->parent = parent;
+	dev_set_name(d->port_dev, "%s:p%d", dev_name(parent), idx + 1);
+	rc = device_add(d->port_dev);
+	if (rc)
+		goto fail_add;
+
+	/* Populate gadget */
+	INIT_LIST_HEAD(&d->gadget.ep_list);
+	d->gadget.ops = &ast_vhub_udc_ops;
+	d->gadget.ep0 = &d->ep0.ep;
+	d->gadget.name = KBUILD_MODNAME;
+	if (vhub->force_usb1)
+		d->gadget.max_speed = USB_SPEED_FULL;
+	else
+		d->gadget.max_speed = USB_SPEED_HIGH;
+	d->gadget.speed = USB_SPEED_UNKNOWN;
+	d->gadget.dev.of_node = vhub->pdev->dev.of_node;
+
+	rc = usb_add_gadget_udc(d->port_dev, &d->gadget);
+	if (rc != 0)
+		goto fail_udc;
+	d->registered = true;
+
+	return 0;
+ fail_udc:
+	device_del(d->port_dev);
+ fail_add:
+	put_device(d->port_dev);
+
+	return rc;
+}
diff --git a/drivers/usb/gadget/udc