[PATCH v4 2/2] usb: gadget: Add xilinx usb2 device support

[PATCH v4 2/2] usb: gadget: Add xilinx usb2 device support

[Subbaraya Sundeep Bhatta]

This patch adds xilinx usb2 device driver support

Signed-off-by: Subbaraya Sundeep Bhatta <sbhatta-gjFFaj9aHVfQT0dZR+AlfA@public.gmane.org>
---
Changes for v4:
	- renamed xlnx,axi-usb2-device-4.00.a to xlnx,usb2-device-4.00.a
Changes for v3:
        - Added pullup function
        - Modified error handling
        - Fixed all v2 comments except DMA interrupt handling
          since polling seems to be faster.
	Please refer to below message thread:
        http://www.kernelhub.org/?p=2&msg=481724

Changes for v2:
        - Added Resume
        - Added Remote wakeup
        - Fixed v1 comments

 drivers/usb/gadget/Kconfig      |   14 +
 drivers/usb/gadget/Makefile     |    1 +
 drivers/usb/gadget/udc-xilinx.c | 2261 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 2276 insertions(+), 0 deletions(-)
 create mode 100644 drivers/usb/gadget/udc-xilinx.c

diff --git a/drivers/usb/gadget/Kconfig b/drivers/usb/gadget/Kconfig
index ba18e9c..ee919a9 100644
--- a/drivers/usb/gadget/Kconfig
+++ b/drivers/usb/gadget/Kconfig
@@ -459,6 +459,20 @@ config USB_EG20T
 	  ML7213/ML7831 is companion chip for Intel Atom E6xx series.
 	  ML7213/ML7831 is completely compatible for Intel EG20T PCH.
 
+config USB_GADGET_XILINX
+	tristate "Xilinx USB Driver"
+	depends on COMPILE_TEST
+	help
+	  USB peripheral controller driver for Xilinx USB2 device.
+	  Xilinx USB2 device is a soft IP which supports both full
+	  and high speed USB 2.0 data transfers. It has seven configurable
+	  endpoints(bulk or interrupt or isochronous), as well as
+	  endpoint zero(for control transfers).
+
+	  Say "y" to link the driver statically, or "m" to build a
+	  dynamically linked module called "udc-xilinx" and force all
+	  gadget drivers to also be dynamically linked.
+
 #
 # LAST -- dummy/emulated controller
 #
diff --git a/drivers/usb/gadget/Makefile b/drivers/usb/gadget/Makefile
index 49514ea..dc6dd41 100644
--- a/drivers/usb/gadget/Makefile
+++ b/drivers/usb/gadget/Makefile
@@ -35,6 +35,7 @@ obj-$(CONFIG_USB_FUSB300)	+= fusb300_udc.o
 obj-$(CONFIG_USB_FOTG210_UDC)	+= fotg210-udc.o
 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
 
 # USB Functions
 usb_f_acm-y			:= f_acm.o
diff --git a/drivers/usb/gadget/udc-xilinx.c b/drivers/usb/gadget/udc-xilinx.c
new file mode 100644
index 0000000..ec6ed56
--- /dev/null
+++ b/drivers/usb/gadget/udc-xilinx.c
@@ -0,0 +1,2261 @@
+/*
+ * Xilinx USB peripheral controller driver
+ *
+ * Copyright (C) 2004 by Thomas Rathbone
+ * Copyright (C) 2005 by HP Labs
+ * Copyright (C) 2005 by David Brownell
+ * Copyright (C) 2010 - 2014 Xilinx, Inc.
+ *
+ * Some parts of this driver code is based on the driver for at91-series
+ * USB peripheral controller (at91_udc.c).
+ *
+ * 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/delay.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include "gadget_chips.h"
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#include <linux/of_irq.h>
+#include <linux/prefetch.h>
+#include <linux/usb/ch9.h>
+#include <linux/usb/gadget.h>
+
+/* Register offsets for the USB device.*/
+#define XUSB_EP0_CONFIG_OFFSET		0x0000  /* EP0 Config Reg Offset */
+#define XUSB_SETUP_PKT_ADDR_OFFSET	0x0080  /* Setup Packet Address */
+#define XUSB_ADDRESS_OFFSET		0x0100  /* Address Register */
+#define XUSB_CONTROL_OFFSET		0x0104  /* Control Register */
+#define XUSB_STATUS_OFFSET		0x0108  /* Status Register */
+#define XUSB_FRAMENUM_OFFSET		0x010C	/* Frame Number Register */
+#define XUSB_IER_OFFSET			0x0110	/* Interrupt Enable Register */
+#define XUSB_BUFFREADY_OFFSET		0x0114	/* Buffer Ready Register */
+#define XUSB_TESTMODE_OFFSET		0x0118	/* Test Mode Register */
+#define XUSB_DMA_RESET_OFFSET		0x0200  /* DMA Soft Reset Register */
+#define XUSB_DMA_CONTROL_OFFSET		0x0204	/* DMA Control Register */
+#define XUSB_DMA_DSAR_ADDR_OFFSET	0x0208	/* DMA source Address Reg */
+#define XUSB_DMA_DDAR_ADDR_OFFSET	0x020C	/* DMA destination Addr Reg */
+#define XUSB_DMA_LENGTH_OFFSET		0x0210	/* DMA Length Register */
+#define XUSB_DMA_STATUS_OFFSET		0x0214	/* DMA Status Register */
+
+/* Endpoint Configuration Space offsets */
+#define XUSB_EP_CFGSTATUS_OFFSET	0x00	/* Endpoint Config Status  */
+#define XUSB_EP_BUF0COUNT_OFFSET	0x08	/* Buffer 0 Count */
+#define XUSB_EP_BUF1COUNT_OFFSET	0x0C	/* Buffer 1 Count */
+
+#define XUSB_CONTROL_USB_READY_MASK	0x80000000 /* USB ready Mask */
+#define XUSB_CONTROL_USB_RMTWAKE_MASK	0x40000000 /* Remote wake up mask */
+
+/* Interrupt register related masks.*/
+#define XUSB_STATUS_GLOBAL_INTR_MASK	0x80000000 /* Global Intr Enable */
+#define XUSB_STATUS_DMADONE_MASK	0x04000000 /* DMA done Mask */
+#define XUSB_STATUS_DMAERR_MASK		0x02000000 /* DMA Error Mask */
+#define XUSB_STATUS_DMABUSY_MASK	0x80000000 /* DMA Error Mask */
+#define XUSB_STATUS_RESUME_MASK		0x01000000 /* USB Resume Mask */
+#define XUSB_STATUS_RESET_MASK		0x00800000 /* USB Reset Mask */
+#define XUSB_STATUS_SUSPEND_MASK	0x00400000 /* USB Suspend Mask */
+#define XUSB_STATUS_DISCONNECT_MASK	0x00200000 /* USB Disconnect Mask */
+#define XUSB_STATUS_FIFO_BUFF_RDY_MASK	0x00100000 /* FIFO Buff Ready Mask */
+#define XUSB_STATUS_FIFO_BUFF_FREE_MASK	0x00080000 /* FIFO Buff Free Mask */
+#define XUSB_STATUS_SETUP_PACKET_MASK	0x00040000 /* Setup packet received */
+#define XUSB_STATUS_EP1_BUFF2_COMP_MASK	0x00000200 /* EP 1 Buff 2 Processed */
+#define XUSB_STATUS_EP1_BUFF1_COMP_MASK	0x00000002 /* EP 1 Buff 1 Processed */
+#define XUSB_STATUS_EP0_BUFF2_COMP_MASK	0x00000100 /* EP 0 Buff 2 Processed */
+#define XUSB_STATUS_EP0_BUFF1_COMP_MASK	0x00000001 /* EP 0 Buff 1 Processed */
+#define XUSB_STATUS_HIGH_SPEED_MASK	0x00010000 /* USB Speed Mask */
+/* Suspend,Reset,Suspend and Disconnect Mask */
+#define XUSB_STATUS_INTR_EVENT_MASK	0x01E00000
+/* Buffers  completion Mask */
+#define XUSB_STATUS_INTR_BUFF_COMP_ALL_MASK	0x0000FEFF
+/* Mask for buffer 0 and buffer 1 completion for all Endpoints */
+#define XUSB_STATUS_INTR_BUFF_COMP_SHIFT_MASK	0x00000101
+#define XUSB_STATUS_EP_BUFF2_SHIFT	8	   /* EP buffer offset */
+
+/* Endpoint Configuration Status Register */
+#define XUSB_EP_CFG_VALID_MASK		0x80000000 /* Endpoint Valid bit */
+#define XUSB_EP_CFG_STALL_MASK		0x40000000 /* Endpoint Stall bit */
+#define XUSB_EP_CFG_DATA_TOGGLE_MASK	0x08000000 /* Endpoint Data toggle */
+
+/* USB device specific global configuration constants.*/
+#define XUSB_MAX_ENDPOINTS		8	/* Maximum End Points */
+#define XUSB_EP_NUMBER_ZERO		0	/* End point Zero */
+/* DPRAM is the source address for DMA transfer */
+#define XUSB_DMA_READ_FROM_DPRAM	0x80000000
+#define XUSB_DMA_DMASR_BUSY		0x80000000 /* DMA busy */
+#define XUSB_DMA_DMASR_ERROR		0x40000000 /* DMA Error */
+/*
+ * When this bit is set, the DMA buffer ready bit is set by hardware upon
+ * DMA transfer completion.
+ */
+#define XUSB_DMA_BRR_CTRL		0x40000000 /* DMA bufready ctrl bit */
+/* Phase States */
+#define SETUP_PHASE			0x0000	/* Setup Phase */
+#define DATA_PHASE			0x0001  /* Data Phase */
+#define STATUS_PHASE			0x0002  /* Status Phase */
+
+#define EP0_MAX_PACKET		64 /* Endpoint 0 maximum packet length */
+
+/* container_of helper macros */
+#define to_udc(g)	 container_of((g), struct xusb_udc, gadget)
+#define to_xusb_ep(ep)	 container_of((ep), struct xusb_ep, ep_usb)
+#define to_xusb_req(req) container_of((req), struct xusb_req, usb_req)
+
+/**
+ * struct xusb_req - Xilinx USB device request structure
+ * @usb_req: Linux usb request structure
+ * @queue: usb device request queue
+ * @ep: pointer to xusb_endpoint structure
+ */
+struct xusb_req {
+	struct usb_request usb_req;
+	struct list_head queue;
+	struct xusb_ep *ep;
+};
+
+/**
+ * struct xusb_ep - USB end point structure.
+ * @ep_usb: usb endpoint instance
+ * @queue: endpoint message queue
+ * @udc: xilinx usb peripheral driver instance pointer
+ * @desc: pointer to the usb endpoint descriptor
+ * @rambase: the endpoint buffer address
+ * @offset: the endpoint register offset value
+ * @name: name of the endpoint
+ * @epnumber: endpoint number
+ * @maxpacket: maximum packet size the endpoint can store
+ * @buffer0count: the size of the packet recieved in the first buffer
+ * @buffer1count: the size of the packet received in the second buffer
+ * @buffer0ready: the busy state of first buffer
+ * @buffer1ready: the busy state of second buffer
+ * @eptype: endpoint transfer type (BULK, INTERRUPT)
+ * @curbufnum: current buffer of endpoint that will be processed next
+ * @is_in: endpoint direction (IN or OUT)
+ * @is_iso: endpoint type(isochronous or non isochronous)
+ */
+struct xusb_ep {
+	struct usb_ep ep_usb;
+	struct list_head queue;
+	struct xusb_udc *udc;
+	const struct usb_endpoint_descriptor *desc;
+	u32 rambase;
+	u32 offset;
+	char name[4];
+	u16 epnumber;
+	u16 maxpacket;
+	u16 buffer0count;
+	u16 buffer1count;
+	u8 buffer0ready;
+	u8 buffer1ready;
+	u8 eptype;
+	u8 curbufnum;
+	u8 is_in;
+	u8 is_iso;
+};
+
+/**
+ * struct xusb_udc -  USB peripheral driver structure
+ * @gadget: USB gadget driver instance
+ * @ep: an array of endpoint structures
+ * @driver: pointer to the usb gadget driver instance
+ * @setup: usb_ctrlrequest structure for control requests
+ * @req: pointer to dummy request for get status command
+ * @dev: pointer to device structure in gadget
+ * @usb_state: device in suspended state or not
+ * @remote_wkp: remote wakeup enabled by host
+ * @setupseqtx: tx status
+ * @setupseqrx: rx status
+ * @base_address: the usb device base address
+ * @lock: instance of spinlock
+ * @dma_enabled: flag indicating whether the dma is included in the system
+ * @read_fn: function pointer to read device registers
+ * @write_fn: function pointer to write to device registers
+ */
+struct xusb_udc {
+	struct usb_gadget gadget;
+	struct xusb_ep ep[8];
+	struct usb_gadget_driver *driver;
+	struct usb_ctrlrequest setup;
+	struct xusb_req *req;
+	struct device *dev;
+	u32 usb_state;
+	u32 remote_wkp;
+	u32 setupseqtx;
+	u32 setupseqrx;
+	void __iomem *base_address;
+	spinlock_t lock;
+	bool dma_enabled;
+
+	unsigned int (*read_fn)(void __iomem *);
+	void (*write_fn)(void __iomem *, u32, u32);
+};
+
+/* Endpoint buffer start addresses in the core */
+static u32 rambase[8] = { 0x22, 0x1000, 0x1100, 0x1200, 0x1300, 0x1400, 0x1500,
+			0x1600 };
+
+static const char driver_name[] = "xilinx-udc";
+static const char ep0name[] = "ep0";
+
+/* Control endpoint configuration.*/
+static const struct usb_endpoint_descriptor config_bulk_out_desc = {
+	.bLength		= USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType	= USB_DT_ENDPOINT,
+	.bEndpointAddress	= USB_DIR_OUT,
+	.bmAttributes		= USB_ENDPOINT_XFER_BULK,
+	.wMaxPacketSize		= cpu_to_le16(64),
+};
+
+/**
+ * xudc_write32 - little endian write to device registers
+ * @addr: base addr of device registers
+ * @offset: register offset
+ * @val: data to be written
+ */
+static void xudc_write32(void __iomem *addr, u32 offset, u32 val)
+{
+	iowrite32(val, addr + offset);
+}
+
+/**
+ * xudc_read32 - little endian read from device registers
+ * @addr: addr of device register
+ * Return: value at addr
+ */
+static unsigned int xudc_read32(void __iomem *addr)
+{
+	return ioread32(addr);
+}
+
+/**
+ * xudc_write32_be - big endian write to device registers
+ * @addr: base addr of device registers
+ * @offset: register offset
+ * @val: data to be written
+ */
+static void xudc_write32_be(void __iomem *addr, u32 offset, u32 val)
+{
+	iowrite32be(val, addr + offset);
+}
+
+/**
+ * xudc_read32_be - big endian read from device registers
+ * @addr: addr of device register
+ * Return: value at addr
+ */
+static unsigned int xudc_read32_be(void __iomem *addr)
+{
+	return ioread32be(addr);
+}
+
+/**
+ * xudc_wrstatus - Sets up the usb device status stages.
+ * @udc: pointer to the usb device controller structure.
+ */
+static void xudc_wrstatus(struct xusb_udc *udc)
+{
+	struct xusb_ep *ep0 = &udc->ep[XUSB_EP_NUMBER_ZERO];
+	u32 epcfgreg;
+
+	epcfgreg = udc->read_fn(udc->base_address + ep0->offset)|
+			XUSB_EP_CFG_DATA_TOGGLE_MASK;
+	udc->write_fn(udc->base_address, ep0->offset, epcfgreg);
+	udc->write_fn(udc->base_address, ep0->offset + XUSB_EP_BUF0COUNT_OFFSET,
+			0);
+	udc->write_fn(udc->base_address, XUSB_BUFFREADY_OFFSET, 1);
+}
+
+/**
+ * xudc_epconfig - Configures the given endpoint.
+ * @ep: pointer to the usb device endpoint structure.
+ * @udc: pointer to the usb peripheral controller structure.
+ *
+ * This function configures a specific endpoint with the given configuration
+ * data.
+ */
+static void xudc_epconfig(struct xusb_ep *ep, struct xusb_udc *udc)
+{
+	u32 epcfgreg;
+
+	/*
+	 * Configure the end point direction, type, Max Packet Size and the
+	 * EP buffer location.
+	 */
+	epcfgreg = ((ep->is_in << 29) | (ep->eptype << 28) |
+			(ep->ep_usb.maxpacket << 15) | (ep->rambase));
+	udc->write_fn(udc->base_address, ep->offset, epcfgreg);
+
+	/* Set the Buffer count and the Buffer ready bits.*/
+	udc->write_fn(udc->base_address, ep->offset + XUSB_EP_BUF0COUNT_OFFSET,
+			ep->buffer0count);
+	udc->write_fn(udc->base_address, ep->offset + XUSB_EP_BUF1COUNT_OFFSET,
+			ep->buffer1count);
+	if (ep->buffer0ready)
+		udc->write_fn(udc->base_address, XUSB_BUFFREADY_OFFSET,
+				1 << ep->epnumber);
+	if (ep->buffer1ready)
+		udc->write_fn(udc->base_address, XUSB_BUFFREADY_OFFSET, 1 <<
+				 (ep->epnumber + XUSB_STATUS_EP_BUFF2_SHIFT));
+}
+
+/**
+ * xudc_start_dma - Starts DMA transfer.
+ * @ep: pointer to the usb device endpoint structure.
+ * @src: DMA source address.
+ * @dst: DMA destination address.
+ * @length: number of bytes to transfer.
+ *
+ * Return: 0 on success, error code on failure
+ *
+ * This function starts DMA transfer by writing to DMA source,
+ * destination and lenth registers.
+ */
+static int xudc_start_dma(struct xusb_ep *ep, dma_addr_t src,
+		dma_addr_t dst, u32 length)
+{
+	struct xusb_udc *udc = ep->udc;
+	int rc = 0;
+	u32 timeout = 500;
+	u32 reg;
+
+	/*
+	 * Set the addresses in the DMA source and
+	 * destination registers and then set the length
+	 * into the DMA length register.
+	 */
+	udc->write_fn(udc->base_address, XUSB_DMA_DSAR_ADDR_OFFSET, src);
+	udc->write_fn(udc->base_address, XUSB_DMA_DDAR_ADDR_OFFSET, dst);
+	udc->write_fn(udc->base_address, XUSB_DMA_LENGTH_OFFSET, length);
+
+	/*
+	 * Wait till DMA transaction is complete and
+	 * check whether the DMA transaction was
+	 * successful.
+	 */
+	do {
+		reg = udc->read_fn(udc->base_address + XUSB_DMA_STATUS_OFFSET);
+		if (!(reg &  XUSB_DMA_DMASR_BUSY))
+			break;
+
+		/*
+		 * We can't sleep here, because it's also called from
+		 * interrupt context.
+		 */
+		timeout--;
+		if (!timeout) {
+			dev_err(udc->dev, "DMA timeout\n");
+			return -ETIMEDOUT;
+		}
+		udelay(1);
+	} while (1);
+
+	if ((udc->read_fn(udc->base_address + XUSB_DMA_STATUS_OFFSET) &
+			XUSB_DMA_DMASR_ERROR) == XUSB_DMA_DMASR_ERROR){
+		dev_err(udc->dev, "DMA Error\n");
+		rc = -EINVAL;
+	}
+
+	return rc;
+}
+
+/**
+ * xudc_dma_send - Sends IN data using DMA.
+ * @ep: pointer to the usb device endpoint structure.
+ * @req: pointer to the usb request structure.
+ * @buffer: pointer to data to be sent.
+ * @length: number of bytes to send.
+ *
+ * Return: 0 on success, -EAGAIN if no buffer is free and error
+ *	   code on failure.
+ *
+ * This function sends data using DMA.
+ */
+static int xudc_dma_send(struct xusb_ep *ep, struct xusb_req *req,
+		u8 *buffer, u32 length)
+{
+	u32 *eprambase;
+	dma_addr_t src;
+	dma_addr_t dst;
+	int ret;
+	struct xusb_udc *udc = ep->udc;
+
+	src = req->usb_req.dma + req->usb_req.actual;
+	if (req->usb_req.length)
+		dma_sync_single_for_device(udc->dev, src,
+						length, DMA_TO_DEVICE);
+	if (!ep->curbufnum && !ep->buffer0ready) {
+		/* Get the Buffer address and copy the transmit data.*/
+		eprambase = (u32 __force *)(udc->base_address +
+				ep->rambase);
+		dst = virt_to_phys(eprambase);
+		udc->write_fn(udc->base_address, ep->offset +
+				XUSB_EP_BUF0COUNT_OFFSET, length);
+		udc->write_fn(udc->base_address, XUSB_DMA_CONTROL_OFFSET,
+				XUSB_DMA_BRR_CTRL | (1 << ep->epnumber));
+		ep->buffer0ready = 1;
+		ep->curbufnum = 1;
+	} else if (ep->curbufnum && !ep->buffer1ready) {
+		/* Get the Buffer address and copy the transmit data.*/
+		eprambase = (u32 __force *)(udc->base_address +
+				ep->rambase + ep->ep_usb.maxpacket);
+		dst = virt_to_phys(eprambase);
+		udc->write_fn(udc->base_address, ep->offset +
+				XUSB_EP_BUF1COUNT_OFFSET, length);
+		udc->write_fn(udc->base_address, XUSB_DMA_CONTROL_OFFSET,
+				XUSB_DMA_BRR_CTRL | (1 << (ep->epnumber +
+				XUSB_STATUS_EP_BUFF2_SHIFT)));
+		ep->buffer1ready = 1;
+		ep->curbufnum = 0;
+	} else {
+		/* None of ping pong buffers are ready currently .*/
+		return -EAGAIN;
+	}
+
+	ret = xudc_start_dma(ep, src, dst, length);
+	return ret;
+}
+
+/**
+ * xudc_dma_receive - Receives OUT data using DMA.
+ * @ep: pointer to the usb device endpoint structure.
+ * @req: pointer to the usb request structure.
+ * @buffer: pointer to storage buffer of received data.
+ * @length: number of bytes to receive.
+ *
+ * Return: 0 on success, -EAGAIN if no buffer is free and error
+ *	   code on failure.
+ *
+ * This function receives data using DMA.
+ */
+static int xudc_dma_receive(struct xusb_ep *ep, struct xusb_req *req,
+		u8 *buffer, u32 length)
+{
+	u32 *eprambase;
+	dma_addr_t src;
+	dma_addr_t dst;
+	int ret = 0;
+	struct xusb_udc *udc = ep->udc;
+
+	dst = req->usb_req.dma + req->usb_req.actual;
+
+	if (!ep->curbufnum && !ep->buffer0ready) {
+		/* Get the Buffer address and copy the transmit data */
+		eprambase = (u32 __force *)(udc->base_address +
+				ep->rambase);
+		src = virt_to_phys(eprambase);
+		udc->write_fn(udc->base_address, XUSB_DMA_CONTROL_OFFSET,
+				XUSB_DMA_BRR_CTRL | XUSB_DMA_READ_FROM_DPRAM |
+				(1 << ep->epnumber));
+		ep->buffer0ready = 1;
+		ep->curbufnum = 1;
+	} else if (ep->curbufnum && !ep->buffer1ready) {
+		/* Get the Buffer address and copy the transmit data */
+		eprambase = (u32 __force *)(udc->base_address +
+				ep->rambase + ep->ep_usb.maxpacket);
+		src = virt_to_phys(eprambase);
+		udc->write_fn(udc->base_address, XUSB_DMA_CONTROL_OFFSET,
+				XUSB_DMA_BRR_CTRL | XUSB_DMA_READ_FROM_DPRAM |
+				(1 << (ep->epnumber +
+				XUSB_STATUS_EP_BUFF2_SHIFT)));
+		ep->buffer1ready = 1;
+		ep->curbufnum = 0;
+	} else {
+		/* None of the ping-pong buffers are ready currently */
+		return -EAGAIN;
+	}
+
+	ret = xudc_start_dma(ep, src, dst, length);
+	return ret;
+}
+
+/**
+ * xudc_eptxrx - Transmits or receives data to or from an endpoint.
+ * @ep: pointer to the usb endpoint configuration structure.
+ * @req: pointer to the usb request structure.
+ * @bufferptr: pointer to buffer containing the data to be sent.
+ * @bufferlen: The number of data bytes to be sent.
+ *
+ * Return: 0 on success, -EAGAIN if no buffer is free.
+ *
+ * This function copies the transmit/receive data to/from the end point buffer
+ * and enables the buffer for transmission/reception.
+ */
+static int xudc_eptxrx(struct xusb_ep *ep, struct xusb_req *req,
+		u8 *bufferptr, u32 bufferlen)
+{
+	u32 *eprambase;
+	u32 bytestosend;
+	u8 *temprambase;
+	int rc = 0;
+	struct xusb_udc *udc = ep->udc;
+
+	bytestosend = bufferlen;
+	if (udc->dma_enabled) {
+		if (ep->is_in)
+			rc = xudc_dma_send(ep, req, bufferptr, bufferlen);
+		else
+			rc = xudc_dma_receive(ep, req, bufferptr, bufferlen);
+		return rc;
+	}
+	/* Put the transmit buffer into the correct ping-pong buffer.*/
+	if (!ep->curbufnum && !ep->buffer0ready) {
+		/* Get the Buffer address and copy the transmit data.*/
+		eprambase = (u32 __force *)(udc->base_address + ep->rambase);
+		while (bytestosend > 3) {
+			if (ep->is_in)
+				*eprambase++ = *(u32 *)bufferptr;
+			else
+				*(u32 *)bufferptr = *eprambase++;
+			bufferptr += 4;
+			bytestosend -= 4;
+		}
+		temprambase = (u8 *)eprambase;
+		while (bytestosend--) {
+			if (ep->is_in)
+				*temprambase++ = *bufferptr++;
+			else
+				*bufferptr++ = *temprambase++;
+		}
+		/*
+		 * Set the Buffer count register with transmit length
+		 * and enable the buffer for transmission.
+		 */
+		if (ep->is_in)
+			udc->write_fn(udc->base_address, ep->offset +
+					XUSB_EP_BUF0COUNT_OFFSET, bufferlen);
+		udc->write_fn(udc->base_address, XUSB_BUFFREADY_OFFSET,
+				1 << ep->epnumber);
+		ep->buffer0ready = 1;
+		ep->curbufnum = 1;
+	} else if ((ep->curbufnum == 1) && (!ep->buffer1ready)) {
+		/* Get the Buffer address and copy the transmit data.*/
+		eprambase = (u32 __force *)(udc->base_address + ep->rambase +
+				ep->ep_usb.maxpacket);
+		while (bytestosend > 3) {
+			if (ep->is_in)
+				*eprambase++ = *(u32 *)bufferptr;
+			else
+				*(u32 *)bufferptr = *eprambase++;
+			bufferptr += 4;
+			bytestosend -= 4;
+		}
+		temprambase = (u8 *)eprambase;
+		while (bytestosend--) {
+			if (ep->is_in)
+				*temprambase++ = *bufferptr++;
+			else
+				*bufferptr++ = *temprambase++;
+		}
+		/*
+		 * Set the Buffer count register with transmit
+		 * length and enable the buffer for
+		 * transmission.
+		 */
+		if (ep->is_in)
+			udc->write_fn(udc->base_address, ep->offset +
+					XUSB_EP_BUF1COUNT_OFFSET, bufferlen);
+		udc->write_fn(udc->base_address, XUSB_BUFFREADY_OFFSET,
+				1 << (ep->epnumber +
+				XUSB_STATUS_EP_BUFF2_SHIFT));
+		ep->buffer1ready = 1;
+		ep->curbufnum = 0;
+	} else {
+		/* None of the ping-pong buffers are ready currently */
+		return -EAGAIN;
+	}
+	return rc;
+}
+
+/**
+ * xudc_done - Exeutes the endpoint data transfer completion tasks.
+ * @ep: pointer to the usb device endpoint structure.
+ * @req: pointer to the usb request structure.
+ * @status: Status of the data transfer.
+ *
+ * Deletes the message from the queue and updates data transfer completion
+ * status.
+ */
+static void xudc_done(struct xusb_ep *ep, struct xusb_req *req, int status)
+{
+	struct xusb_udc *udc = ep->udc;
+
+	list_del_init(&req->queue);
+
+	if (req->usb_req.status == -EINPROGRESS)
+		req->usb_req.status = status;
+	else
+		status = req->usb_req.status;
+
+	if (status && status != -ESHUTDOWN)
+		dev_dbg(udc->dev, "%s done %p, status %d\n",
+				ep->ep_usb.name, req, status);
+	/* unmap request if DMA is present*/
+	if (udc->dma_enabled && ep->epnumber && req->usb_req.length)
+		usb_gadget_unmap_request(&udc->gadget, &req->usb_req,
+						ep->is_in);
+
+	if (req->usb_req.complete) {
+		spin_unlock(&udc->lock);
+		req->usb_req.complete(&ep->ep_usb, &req->usb_req);
+		spin_lock(&udc->lock);
+	}
+}
+
+/**
+ * xudc_read_fifo - Reads the data from the given endpoint buffer.
+ * @ep: pointer to the usb device endpoint structure.
+ * @req: pointer to the usb request structure.
+ *
+ * Return: 0 if request is completed and -EAGAIN if not completed.
+ *
+ * Pulls OUT packet data from the endpoint buffer.
+ */
+static int xudc_read_fifo(struct xusb_ep *ep, struct xusb_req *req)
+{
+	u8 *buf;
+	u32 is_short, count, bufferspace;
+	u8 bufoffset;
+	u8 two_pkts = 0;
+	int ret;
+	int retval = -EAGAIN;
+	struct xusb_udc *udc = ep->udc;
+
+	if ((ep->buffer0ready == 1) && (ep->buffer1ready == 1)) {
+		dev_dbg(udc->dev, "Packet NOT ready!\n");
+		return retval;
+	}
+top:
+	if (ep->curbufnum)
+		bufoffset = XUSB_EP_BUF1COUNT_OFFSET;
+	else
+		bufoffset = XUSB_EP_BUF0COUNT_OFFSET;
+
+	count = udc->read_fn(udc->base_address + ep->offset + bufoffset);
+
+	if (!ep->buffer0ready && !ep->buffer1ready)
+		two_pkts = 1;
+
+	buf = req->usb_req.buf + req->usb_req.actual;
+	prefetchw(buf);
+	bufferspace = req->usb_req.length - req->usb_req.actual;
+	is_short = count < ep->ep_usb.maxpacket;
+
+	if (unlikely(!bufferspace)) {
+		/*
+		 * This happens when the driver's buffer
+		 * is smaller than what the host sent.
+		 * discard the extra data.
+		 */
+		if (req->usb_req.status != -EOVERFLOW)
+			dev_dbg(udc->dev,
+					"%s overflow %d\n",
+					ep->ep_usb.name, count);
+		req->usb_req.status = -EOVERFLOW;
+		xudc_done(ep, req, -EOVERFLOW);
+		return 0;
+	}
+
+	ret = xudc_eptxrx(ep, req, buf, count);
+	switch (ret) {
+	case 0:
+		req->usb_req.actual += min(count, bufferspace);
+		dev_dbg(udc->dev, "read %s, %d bytes%s req %p %d/%d\n",
+			ep->ep_usb.name, count, is_short ? "/S" : "", req,
+			req->usb_req.actual, req->usb_req.length);
+		bufferspace -= count;
+		/* Completion */
+		if ((req->usb_req.actual == req->usb_req.length) || is_short) {
+			if (udc->dma_enabled && req->usb_req.length)
+				dma_sync_single_for_cpu(udc->dev,
+							req->usb_req.dma,
+							req->usb_req.actual,
+							DMA_FROM_DEVICE);
+			xudc_done(ep, req, 0);
+			return 0;
+		}
+		if (two_pkts) {
+			two_pkts = 0;
+			goto top;
+		}
+		break;
+	case -EAGAIN:
+		dev_dbg(udc->dev, "receive busy\n");
+		break;
+	case -EINVAL:
+	case -ETIMEDOUT:
+		/* DMA error, dequeue the request */
+		xudc_done(ep, req, -ECONNRESET);
+		retval = 0;
+		break;
+	}
+
+	return retval;
+}
+
+/**
+ * xudc_write_fifo - Writes data into the given endpoint buffer.
+ * @ep: pointer to the usb device endpoint structure.
+ * @req: pointer to the usb request structure.
+ *
+ * Return: 0 if request is completed and -EAGAIN if not completed.
+ *
+ * Loads endpoint buffer for an IN packet.
+ */
+static int xudc_write_fifo(struct xusb_ep *ep, struct xusb_req *req)
+{
+	u32 max;
+	u32 length;
+	int ret;
+	int retval = -EAGAIN;
+	struct xusb_udc *udc = ep->udc;
+	int is_last, is_short = 0;
+	u8 *buf;
+
+	max = le16_to_cpu(ep->desc->wMaxPacketSize);
+	buf = req->usb_req.buf + req->usb_req.actual;
+	prefetch(buf);
+	length = req->usb_req.length - req->usb_req.actual;
+	length = min(length, max);
+
+	ret = xudc_eptxrx(ep, req, buf, length);
+	switch (ret) {
+	case 0:
+		req->usb_req.actual += length;
+		if (unlikely(length != max)) {
+			is_last = is_short = 1;
+		} else {
+			if (likely(req->usb_req.length !=
+				   req->usb_req.actual) || req->usb_req.zero)
+				is_last = 0;
+			else
+				is_last = 1;
+		}
+		dev_dbg(udc->dev,
+			"%s: wrote %s %d bytes%s%s %d left %p\n", __func__,
+			ep->ep_usb.name, length, is_last ? "/L" : "",
+			is_short ? "/S" : "",
+			req->usb_req.length - req->usb_req.actual, req);
+		/* completion */
+		if (is_last) {
+			xudc_done(ep, req, 0);
+			retval = 0;
+		}
+		break;
+	case -EAGAIN:
+		dev_dbg(udc->dev, "Send busy\n");
+		break;
+	case -EINVAL:
+	case -ETIMEDOUT:
+		/* DMA error, dequeue the request */
+		xudc_done(ep, req, -ECONNRESET);
+		retval = 0;
+		break;
+	}
+
+	return retval;
+}
+
+/**
+ * xudc_nuke - Cleans up the data transfer message list.
+ * @ep: pointer to the usb device endpoint structure.
+ * @status: Status of the data transfer.
+ */
+static void xudc_nuke(struct xusb_ep *ep, int status)
+{
+	struct xusb_req *req;
+
+	while (!list_empty(&ep->queue)) {
+		req = list_first_entry(&ep->queue, struct xusb_req, queue);
+		xudc_done(ep, req, status);
+	}
+}
+
+/**
+ * xudc_ep_set_halt - Stalls/unstalls the given endpoint.
+ * @_ep: pointer to the usb device endpoint structure.
+ * @value: value to indicate stall/unstall.
+ *
+ * Return: 0 for success and error value on failure
+ */
+static int xudc_ep_set_halt(struct usb_ep *_ep, int value)
+{
+	struct xusb_ep *ep = to_xusb_ep(_ep);
+	struct xusb_udc *udc;
+	unsigned long flags;
+	u32 epcfgreg;
+
+	if (!_ep || (!ep->desc && ep->epnumber)) {
+		pr_debug("%s: bad ep or descriptor\n", __func__);
+		return -EINVAL;
+	}
+	udc = ep->udc;
+
+	if (ep->is_in && (!list_empty(&ep->queue)) && value) {
+		dev_dbg(udc->dev, "requests pending can't halt\n");
+		return -EAGAIN;
+	}
+
+	if ((ep->buffer0ready == 1) || (ep->buffer1ready == 1)) {
+		dev_dbg(udc->dev, "HW buffers busy can't halt\n");
+		return -EAGAIN;
+	}
+
+	spin_lock_irqsave(&udc->lock, flags);
+
+	if (value) {
+		/* Stall the device.*/
+		epcfgreg = udc->read_fn(udc->base_address + ep->offset);
+		epcfgreg |= XUSB_EP_CFG_STALL_MASK;
+
+		udc->write_fn(udc->base_address, ep->offset, epcfgreg);
+	} else {
+		/* Unstall the device.*/
+		epcfgreg = udc->read_fn(udc->base_address + ep->offset);
+		epcfgreg &= ~XUSB_EP_CFG_STALL_MASK;
+		udc->write_fn(udc->base_address, ep->offset, epcfgreg);
+		if (ep->epnumber) {
+			/* Reset the toggle bit.*/
+			epcfgreg = udc->read_fn(ep->udc->base_address +
+						    ep->offset);
+			epcfgreg &= ~XUSB_EP_CFG_DATA_TOGGLE_MASK;
+			udc->write_fn(udc->base_address, ep->offset, epcfgreg);
+		}
+	}
+
+	spin_unlock_irqrestore(&udc->lock, flags);
+	return 0;
+}
+
+/**
+ * xudc_ep_enable - Enables the given endpoint.
+ * @ep: pointer to the xusb endpoint structure.
+ * @desc: pointer to usb endpoint descriptor.
+ *
+ * Return: 0 for success and error value on failure
+ */
+static int __xudc_ep_enable(struct xusb_ep *ep,
+		const struct usb_endpoint_descriptor *desc)
+{
+	struct xusb_udc *udc = ep->udc;
+	u32 tmp;
+	u8 eptype = 0;
+	u32 epcfg;
+	u32 ier;
+
+	ep->is_in = ((desc->bEndpointAddress & USB_DIR_IN) != 0);
+	/* Bit 3...0:endpoint number */
+	ep->epnumber = (desc->bEndpointAddress & 0x0f);
+	ep->desc = desc;
+	ep->ep_usb.desc = desc;
+	tmp = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
+	ep->ep_usb.maxpacket = le16_to_cpu(desc->wMaxPacketSize);
+
+	switch (tmp) {
+	case USB_ENDPOINT_XFER_CONTROL:
+		dev_dbg(udc->dev, "only one control endpoint\n");
+		/* NON- ISO */
+		eptype = 0;
+		return -EINVAL;
+	case USB_ENDPOINT_XFER_INT:
+		/* NON- ISO */
+		eptype = 0;
+		if (ep->ep_usb.maxpacket > 64)
+			goto bogus_max;
+		break;
+	case USB_ENDPOINT_XFER_BULK:
+		/* NON- ISO */
+		eptype = 0;
+		switch (ep->ep_usb.maxpacket) {
+		case 8:
+		case 16:
+		case 32:
+		case 64:
+		case 512:
+			goto ok;
+		}
+bogus_max:
+		dev_dbg(udc->dev, "bogus maxpacket %d\n",
+			ep->ep_usb.maxpacket);
+		return -EINVAL;
+	case USB_ENDPOINT_XFER_ISOC:
+		/* ISO */
+		eptype = 1;
+		ep->is_iso = 1;
+		break;
+	}
+ok:
+	ep->eptype = eptype;
+	ep->buffer0ready = 0;
+	ep->buffer1ready = 0;
+	ep->curbufnum = 0;
+	ep->rambase = rambase[ep->epnumber];
+	xudc_epconfig(ep, udc);
+
+	dev_dbg(udc->dev, "Enable Endpoint %d max pkt is %d\n",
+		ep->epnumber, ep->ep_usb.maxpacket);
+
+	/* Enable the End point.*/
+	epcfg = udc->read_fn(udc->base_address + ep->offset);
+	epcfg |= XUSB_EP_CFG_VALID_MASK;
+	udc->write_fn(udc->base_address, ep->offset, epcfg);
+	if (ep->epnumber)
+		ep->rambase <<= 2;
+
+	/* Enable buffer completion interrupts for endpoint */
+	ier = udc->read_fn(udc->base_address + XUSB_IER_OFFSET);
+	ier |= (XUSB_STATUS_INTR_BUFF_COMP_SHIFT_MASK << ep->epnumber);
+	udc->write_fn(udc->base_address, XUSB_IER_OFFSET, ier);
+
+	/* for OUT endpoint set buffers ready to receive */
+	if (ep->epnumber && !ep->is_in) {
+		udc->write_fn(udc->base_address, XUSB_BUFFREADY_OFFSET,
+				1 << ep->epnumber);
+		ep->buffer0ready = 1;
+		udc->write_fn(udc->base_address, XUSB_BUFFREADY_OFFSET,
+				(1 << (ep->epnumber +
+				XUSB_STATUS_EP_BUFF2_SHIFT)));
+		ep->buffer1ready = 1;
+	}
+
+	return 0;
+}
+
+/**
+ * xudc_ep_enable - Enables the given endpoint.
+ * @_ep: pointer to the usb endpoint structure.
+ * @desc: pointer to usb endpoint descriptor.
+ *
+ * Return: 0 for success and error value on failure
+ */
+static int xudc_ep_enable(struct usb_ep *_ep,
+		const struct usb_endpoint_descriptor *desc)
+{
+	struct xusb_ep *ep;
+	struct xusb_udc *udc;
+	unsigned long flags;
+	int ret;
+
+	if (!_ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT) {
+		pr_debug("%s: bad ep or descriptor\n", __func__);
+		return -EINVAL;
+	}
+
+	ep = to_xusb_ep(_ep);
+	udc = ep->udc;
+
+	if (!udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN) {
+		dev_dbg(udc->dev, "bogus device state\n");
+		return -ESHUTDOWN;
+	}
+
+	spin_lock_irqsave(&udc->lock, flags);
+	ret = __xudc_ep_enable(ep, desc);
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	return ret;
+}
+
+/**
+ * xudc_ep_disable - Disables the given endpoint.
+ * @_ep: pointer to the usb endpoint structure.
+ *
+ * Return: 0 for success and error value on failure
+ */
+static int xudc_ep_disable(struct usb_ep *_ep)
+{
+	struct xusb_ep *ep;
+	unsigned long flags;
+	u32 epcfg;
+	struct xusb_udc *udc;
+
+	if (!_ep) {
+		pr_debug("%s: invalid ep\n", __func__);
+		return -EINVAL;
+	}
+
+	ep = to_xusb_ep(_ep);
+	udc = ep->udc;
+
+	spin_lock_irqsave(&udc->lock, flags);
+
+	xudc_nuke(ep, -ESHUTDOWN);
+
+	/* Restore the endpoint's pristine config */
+	ep->desc = NULL;
+	ep->ep_usb.desc = NULL;
+
+	dev_dbg(udc->dev, "USB Ep %d disable\n ", ep->epnumber);
+	/* Disable the endpoint.*/
+	epcfg = udc->read_fn(udc->base_address + ep->offset);
+	epcfg &= ~XUSB_EP_CFG_VALID_MASK;
+	udc->write_fn(udc->base_address, ep->offset, epcfg);
+
+	spin_unlock_irqrestore(&udc->lock, flags);
+	return 0;
+}
+
+/**
+ * xudc_ep_alloc_request - Initializes the request queue.
+ * @_ep: pointer to the usb endpoint structure.
+ * @gfp_flags: Flags related to the request call.
+ *
+ * Return: pointer to request structure on success and a NULL on failure.
+ */
+static struct usb_request *xudc_ep_alloc_request(struct usb_ep *_ep,
+		gfp_t gfp_flags)
+{
+	struct xusb_ep *ep = to_xusb_ep(_ep);
+	struct xusb_udc *udc;
+	struct xusb_req *req;
+
+	udc = ep->udc;
+	req = kzalloc(sizeof(*req), gfp_flags);
+	if (!req) {
+		dev_err(udc->dev, "%s:not enough memory", __func__);
+		return NULL;
+	}
+
+	req->ep = ep;
+	INIT_LIST_HEAD(&req->queue);
+	return &req->usb_req;
+}
+
+/**
+ * xudc_free_request - Releases the request from queue.
+ * @_ep: pointer to the usb device endpoint structure.
+ * @_req: pointer to the usb request structure.
+ */
+static void xudc_free_request(struct usb_ep *_ep, struct usb_request *_req)
+{
+	struct xusb_req *req = to_xusb_req(_req);
+
+	kfree(req);
+}
+
+/**
+ * xudc_ep0_queue - Adds the request to endpoint 0 queue.
+ * @ep0: pointer to the xusb endpoint 0 structure.
+ * @req: pointer to the xusb request structure.
+ *
+ * Return: 0 for success and error value on failure
+ */
+static int __xudc_ep0_queue(struct xusb_ep *ep0, struct xusb_req *req)
+{
+	struct xusb_udc *udc = ep0->udc;
+	u32 length;
+	u8 *corebuf;
+
+	if (!udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN) {
+		dev_dbg(udc->dev, "%s, bogus device state\n",
+			__func__);
+		return -EINVAL;
+	}
+	if (!list_empty(&ep0->queue)) {
+		dev_dbg(udc->dev, "%s:ep0 busy\n", __func__);
+		return -EBUSY;
+	}
+
+	req->usb_req.status = -EINPROGRESS;
+	req->usb_req.actual = 0;
+
+	list_add_tail(&req->queue, &ep0->queue);
+
+	if (udc->setup.bRequestType & USB_DIR_IN) {
+		prefetch(req->usb_req.buf);
+		length = req->usb_req.length;
+		corebuf = (void __force *) ((ep0->rambase << 2) +
+				udc->base_address);
+		length = req->usb_req.actual = min_t(u32, length,
+						EP0_MAX_PACKET);
+		memcpy((void *)corebuf, req->usb_req.buf, length);
+		udc->write_fn(udc->base_address, XUSB_EP_BUF0COUNT_OFFSET,
+				length);
+		udc->write_fn(udc->base_address, XUSB_BUFFREADY_OFFSET, 1);
+	} else {
+		if (udc->setup.wLength) {
+			/* Enable EP0 buffer to receive data */
+			udc->write_fn(udc->base_address,
+					XUSB_EP_BUF0COUNT_OFFSET, 0);
+			udc->write_fn(udc->base_address,
+					XUSB_BUFFREADY_OFFSET, 1);
+		} else {
+			xudc_wrstatus(udc);
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * xudc_ep0_queue - Adds the request to endpoint 0 queue.
+ * @_ep: pointer to the usb endpoint 0 structure.
+ * @_req: pointer to the usb request structure.
+ * @gfp_flags: Flags related to the request call.
+ *
+ * Return: 0 for success and error value on failure
+ */
+static int xudc_ep0_queue(struct usb_ep *_ep, struct usb_request *_req,
+		gfp_t gfp_flags)
+{
+	struct xusb_req *req	= to_xusb_req(_req);
+	struct xusb_ep	*ep0	= to_xusb_ep(_ep);
+	struct xusb_udc *udc	= ep0->udc;
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&udc->lock, flags);
+	ret = __xudc_ep0_queue(ep0, req);
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	return ret;
+}
+
+/**
+ * xudc_ep_queue - Adds the request to endpoint queue.
+ * @_ep: pointer to the usb endpoint structure.
+ * @_req: pointer to the usb request structure.
+ * @gfp_flags: Flags related to the request call.
+ *
+ * Return: 0 for success and error value on failure
+ */
+static int xudc_ep_queue(struct usb_ep *_ep, struct usb_request *_req,
+		gfp_t gfp_flags)
+{
+	struct xusb_req *req = to_xusb_req(_req);
+	struct xusb_ep	*ep  = to_xusb_ep(_ep);
+	struct xusb_udc *udc = ep->udc;
+	int  ret;
+	unsigned long flags;
+
+	if (!ep->desc) {
+		dev_dbg(udc->dev, "%s:queing request to disabled %s\n",
+				__func__, ep->name);
+		return -ESHUTDOWN;
+	}
+
+	if (!udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN) {
+		dev_dbg(udc->dev, "%s, bogus device state\n",
+			__func__);
+		return -EINVAL;
+	}
+
+	spin_lock_irqsave(&udc->lock, flags);
+
+	_req->status = -EINPROGRESS;
+	_req->actual = 0;
+
+	if (udc->dma_enabled) {
+		ret = usb_gadget_map_request(&udc->gadget,
+					&req->usb_req, ep->is_in);
+		if (ret) {
+			dev_dbg(udc->dev, "gadget_map failed ep%d\n",
+					ep->epnumber);
+			spin_unlock_irqrestore(&udc->lock, flags);
+			return -EAGAIN;
+		}
+	}
+
+	if (list_empty(&ep->queue)) {
+		if (ep->is_in) {
+			dev_dbg(udc->dev, "xudc_write_fifo from ep_queue\n");
+			if (!xudc_write_fifo(ep, req))
+				req = NULL;
+		} else {
+			dev_dbg(udc->dev, "xudc_read_fifo from ep_queue\n");
+			if (!xudc_read_fifo(ep, req))
+				req = NULL;
+		}
+	}
+
+	if (req != NULL)
+		list_add_tail(&req->queue, &ep->queue);
+
+	spin_unlock_irqrestore(&udc->lock, flags);
+	return 0;
+}
+
+/**
+ * xudc_ep_dequeue - Removes the request from the queue.
+ * @_ep: pointer to the usb device endpoint structure.
+ * @_req: pointer to the usb request structure.
+ *
+ * Return: 0 for success and error value on failure
+ */
+static int xudc_ep_dequeue(struct usb_ep *_ep, struct usb_request *_req)
+{
+	struct xusb_ep *ep	= to_xusb_ep(_ep);
+	struct xusb_req *req	= to_xusb_req(_req);
+	struct xusb_udc *udc	= ep->udc;
+	unsigned long flags;
+
+	spin_lock_irqsave(&udc->lock, flags);
+	/* Make sure it's actually queued on this endpoint */
+	list_for_each_entry(req, &ep->queue, queue) {
+		if (&req->usb_req == _req)
+			break;
+	}
+	if (&req->usb_req != _req) {
+		spin_unlock_irqrestore(&ep->udc->lock, flags);
+		return -EINVAL;
+	}
+	xudc_done(ep, req, -ECONNRESET);
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	return 0;
+}
+
+/**
+ * xudc_ep0_enable - Enables the given endpoint.
+ * @ep: pointer to the usb endpoint structure.
+ * @desc: pointer to usb endpoint descriptor.
+ *
+ * Return: error always.
+ *
+ * endpoint 0 enable should not be called by gadget layer.
+ */
+static int xudc_ep0_enable(struct usb_ep *ep,
+		const struct usb_endpoint_descriptor *desc)
+{
+	return -EINVAL;
+}
+
+/**
+ * xudc_ep0_disable - Disables the given endpoint.
+ * @ep: pointer to the usb endpoint structure.
+ *
+ * Return: error always.
+ *
+ * endpoint 0 disable should not be called by gadget layer.
+ */
+static int xudc_ep0_disable(struct usb_ep *ep)
+{
+	return -EINVAL;
+}
+
+static const struct usb_ep_ops xusb_ep0_ops = {
+	.enable		= xudc_ep0_enable,
+	.disable	= xudc_ep0_disable,
+	.alloc_request	= xudc_ep_alloc_request,
+	.free_request	= xudc_free_request,
+	.queue		= xudc_ep0_queue,
+	.dequeue	= xudc_ep_dequeue,
+	.set_halt	= xudc_ep_set_halt,
+};
+
+static const struct usb_ep_ops xusb_ep_ops = {
+	.enable		= xudc_ep_enable,
+	.disable	= xudc_ep_disable,
+	.alloc_request	= xudc_ep_alloc_request,
+	.free_request	= xudc_free_request,
+	.queue		= xudc_ep_queue,
+	.dequeue	= xudc_ep_dequeue,
+	.set_halt	= xudc_ep_set_halt,
+};
+
+/**
+ * xudc_get_frame - Reads the current usb frame number.
+ * @gadget: pointer to the usb gadget structure.
+ *
+ * Return: current frame number for success and error value on failure.
+ */
+static int xudc_get_frame(struct usb_gadget *gadget)
+{
+	struct xusb_udc *udc;
+	int frame;
+
+	if (!gadget)
+		return -ENODEV;
+
+	udc = to_udc(gadget);
+	frame = udc->read_fn(udc->base_address + XUSB_FRAMENUM_OFFSET);
+	return frame;
+}
+
+/**
+ * xudc_wakeup - Send remote wakeup signal to host
+ * @gadget: pointer to the usb gadget structure.
+ *
+ * Return: 0 on success and error on failure
+ */
+static int xudc_wakeup(struct usb_gadget *gadget)
+{
+	struct xusb_udc *udc = to_udc(gadget);
+	u32 crtlreg;
+	int status = -EINVAL;
+	unsigned long flags;
+
+	spin_lock_irqsave(&udc->lock, flags);
+
+	/* Remote wake up not enabled by host */
+	if (!udc->remote_wkp)
+		goto done;
+
+	crtlreg = udc->read_fn(udc->base_address + XUSB_CONTROL_OFFSET);
+	crtlreg |= XUSB_CONTROL_USB_RMTWAKE_MASK;
+	/* set remote wake up bit */
+	udc->write_fn(udc->base_address, XUSB_CONTROL_OFFSET, crtlreg);
+	/*
+	 * wait for a while and reset remote wake up bit since this bit
+	 * is not cleared by HW after sending remote wakeup to host.
+	 */
+	mdelay(2);
+
+	crtlreg &= ~XUSB_CONTROL_USB_RMTWAKE_MASK;
+	udc->write_fn(udc->base_address, XUSB_CONTROL_OFFSET, crtlreg);
+	status = 0;
+done:
+	spin_unlock_irqrestore(&udc->lock, flags);
+	return status;
+}
+
+/**
+ * xudc_pullup - start/stop USB traffic
+ * @gadget: pointer to the usb gadget structure.
+ * @is_on: flag to start or stop
+ *
+ * Return: 0 always
+ *
+ * This function starts/stops SIE engine of IP based on is_on.
+ */
+static int xudc_pullup(struct usb_gadget *gadget, int is_on)
+{
+	struct xusb_udc *udc = to_udc(gadget);
+	unsigned long flags;
+	u32 crtlreg;
+
+	spin_lock_irqsave(&udc->lock, flags);
+
+	crtlreg = udc->read_fn(udc->base_address + XUSB_CONTROL_OFFSET);
+	if (is_on)
+		crtlreg |= XUSB_CONTROL_USB_READY_MASK;
+	else
+		crtlreg &= ~XUSB_CONTROL_USB_READY_MASK;
+
+	udc->write_fn(udc->base_address, XUSB_CONTROL_OFFSET, crtlreg);
+
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	return 0;
+}
+
+/**
+ * xudc_eps_init - initialize endpoints.
+ * @udc: pointer to the usb device controller structure.
+ */
+static void xudc_eps_init(struct xusb_udc *udc)
+{
+	u32 ep_number;
+	char name[4];
+
+	INIT_LIST_HEAD(&udc->gadget.ep_list);
+
+	for (ep_number = 0; ep_number < XUSB_MAX_ENDPOINTS; ep_number++) {
+		struct xusb_ep *ep = &udc->ep[ep_number];
+
+		if (ep_number) {
+			list_add_tail(&ep->ep_usb.ep_list,
+					&udc->gadget.ep_list);
+			usb_ep_set_maxpacket_limit(&ep->ep_usb,
+					(unsigned short) ~0);
+			sprintf(name, "ep%d", ep_number);
+			strcpy(ep->name, name);
+			ep->ep_usb.name = ep->name;
+			ep->ep_usb.ops = &xusb_ep_ops;
+		} else {
+			ep->ep_usb.name = ep0name;
+			usb_ep_set_maxpacket_limit(&ep->ep_usb, 64);
+			ep->ep_usb.ops = &xusb_ep0_ops;
+		}
+
+		ep->udc = udc;
+		ep->epnumber = ep_number;
+		ep->desc = NULL;
+		/*
+		 * The configuration register address offset between
+		 * each endpoint is 0x10.
+		 */
+		ep->offset = XUSB_EP0_CONFIG_OFFSET +
+					(ep_number * 0x10);
+		ep->is_in = 0;
+		ep->is_iso = 0;
+		ep->maxpacket = 0;
+		xudc_epconfig(ep, udc);
+
+		/* Initialize one queue per endpoint */
+		INIT_LIST_HEAD(&ep->queue);
+	}
+}
+
+/**
+ * xudc_stop_activity - Stops any further activity on the device.
+ * @udc: pointer to the usb device controller structure.
+ */
+static void xudc_stop_activity(struct xusb_udc *udc)
+{
+	int i;
+	struct xusb_ep *ep;
+
+	for (i = 0; i < XUSB_MAX_ENDPOINTS; i++) {
+		ep = &udc->ep[i];
+		xudc_nuke(ep, -ESHUTDOWN);
+	}
+}
+
+/**
+ * xudc_start - Starts the device.
+ * @gadget: pointer to the usb gadget structure
+ * @driver: pointer to gadget driver structure
+ *
+ * Return: zero on success and error on failure
+ */
+static int xudc_start(struct usb_gadget *gadget,
+		struct usb_gadget_driver *driver)
+{
+	struct xusb_udc *udc	= to_udc(gadget);
+	struct xusb_ep *ep0	= &udc->ep[XUSB_EP_NUMBER_ZERO];
+	const struct usb_endpoint_descriptor *desc = &config_bulk_out_desc;
+	unsigned long flags;
+	int ret = 0;
+
+	spin_lock_irqsave(&udc->lock, flags);
+
+	if (udc->driver) {
+		dev_err(udc->dev, "%s is already bound to %s\n",
+				udc->gadget.name, udc->driver->driver.name);
+		ret = -EBUSY;
+		goto err;
+	}
+
+	/* hook up the driver */
+	udc->driver = driver;
+	udc->gadget.speed = driver->max_speed;
+
+	/* Enable the control endpoint. */
+	ret = __xudc_ep_enable(ep0, desc);
+
+	/* Set device address and remote wakeup to 0 */
+	udc->write_fn(udc->base_address, XUSB_ADDRESS_OFFSET, 0);
+	udc->remote_wkp = 0;
+err:
+	spin_unlock_irqrestore(&udc->lock, flags);
+	return ret;
+}
+
+/**
+ * xudc_stop - stops the device.
+ * @gadget: pointer to the usb gadget structure
+ * @driver: pointer to usb gadget driver structure
+ *
+ * Return: zero always
+ */
+static int xudc_stop(struct usb_gadget *gadget,
+		struct usb_gadget_driver *driver)
+{
+	struct xusb_udc *udc = to_udc(gadget);
+	unsigned long flags;
+
+	spin_lock_irqsave(&udc->lock, flags);
+
+	udc->gadget.speed = USB_SPEED_UNKNOWN;
+	udc->driver = NULL;
+
+	/* Set device address and remote wakeup to 0 */
+	udc->write_fn(udc->base_address, XUSB_ADDRESS_OFFSET, 0);
+	udc->remote_wkp = 0;
+
+	xudc_stop_activity(udc);
+
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	return 0;
+}
+
+static const struct usb_gadget_ops xusb_udc_ops = {
+	.get_frame	= xudc_get_frame,
+	.wakeup		= xudc_wakeup,
+	.pullup		= xudc_pullup,
+	.udc_start	= xudc_start,
+	.udc_stop	= xudc_stop,
+};
+
+/**
+ * xudc_clear_stall_all_ep - clears stall of every endpoint.
+ * @udc: pointer to the udc structure.
+ */
+static void xudc_clear_stall_all_ep(struct xusb_udc *udc)
+{
+	struct xusb_ep *ep;
+	u32 epcfgreg;
+	int i;
+
+	for (i = 0; i < XUSB_MAX_ENDPOINTS; i++) {
+		ep = &udc->ep[i];
+		epcfgreg = udc->read_fn(udc->base_address + ep->offset);
+		epcfgreg &= ~XUSB_EP_CFG_STALL_MASK;
+		udc->write_fn(udc->base_address, ep->offset, epcfgreg);
+		if (ep->epnumber) {
+			/* Reset the toggle bit.*/
+			epcfgreg = udc->read_fn(ep->udc->base_address +
+						ep->offset);
+			epcfgreg &= ~XUSB_EP_CFG_DATA_TOGGLE_MASK;
+			udc->write_fn(udc->base_address, ep->offset, epcfgreg);
+		}
+	}
+}
+
+/**
+ * xudc_startup_handler - The usb device controller interrupt handler.
+ * @udc: pointer to the udc structure.
+ * @intrstatus: The mask value containing the interrupt sources.
+ *
+ * This function handles the RESET,SUSPEND,RESUME and DISCONNECT interrupts.
+ */
+static void xudc_startup_handler(struct xusb_udc *udc, u32 intrstatus)
+{
+	u32 intrreg;
+
+	if (intrstatus & XUSB_STATUS_RESET_MASK) {
+
+		dev_dbg(udc->dev, "Reset\n");
+
+		if (intrstatus & XUSB_STATUS_HIGH_SPEED_MASK)
+			udc->gadget.speed = USB_SPEED_HIGH;
+		else
+			udc->gadget.speed = USB_SPEED_FULL;
+
+		xudc_stop_activity(udc);
+		xudc_clear_stall_all_ep(udc);
+		udc->write_fn(udc->base_address, XUSB_TESTMODE_OFFSET, 0);
+
+		/* Set device address and remote wakeup to 0 */
+		udc->write_fn(udc->base_address, XUSB_ADDRESS_OFFSET, 0);
+		udc->remote_wkp = 0;
+
+		/* Enable the suspend, resume and disconnect */
+		intrreg = udc->read_fn(udc->base_address + XUSB_IER_OFFSET);
+		intrreg |= XUSB_STATUS_SUSPEND_MASK | XUSB_STATUS_RESUME_MASK |
+				XUSB_STATUS_DISCONNECT_MASK;
+		udc->write_fn(udc->base_address, XUSB_IER_OFFSET, intrreg);
+	}
+	if (intrstatus & XUSB_STATUS_SUSPEND_MASK) {
+
+		dev_dbg(udc->dev, "Suspend\n");
+
+		/* Enable the reset, resume and disconnect */
+		intrreg = udc->read_fn(udc->base_address + XUSB_IER_OFFSET);
+		intrreg |= XUSB_STATUS_RESET_MASK | XUSB_STATUS_RESUME_MASK |
+				 XUSB_STATUS_DISCONNECT_MASK;
+		udc->write_fn(udc->base_address, XUSB_IER_OFFSET, intrreg);
+
+		udc->usb_state = USB_STATE_SUSPENDED;
+
+		if (udc->driver->suspend) {
+			spin_unlock(&udc->lock);
+			udc->driver->suspend(&udc->gadget);
+			spin_lock(&udc->lock);
+		}
+	}
+	if (intrstatus & XUSB_STATUS_RESUME_MASK) {
+		bool condition = (udc->usb_state != USB_STATE_SUSPENDED);
+
+		dev_WARN_ONCE(udc->dev, condition,
+				"Resume IRQ while not suspended\n");
+
+		dev_dbg(udc->dev, "Resume\n");
+
+		/* Enable the reset, suspend and disconnect */
+		intrreg = udc->read_fn(udc->base_address + XUSB_IER_OFFSET);
+		intrreg |= XUSB_STATUS_RESET_MASK | XUSB_STATUS_SUSPEND_MASK |
+				 XUSB_STATUS_DISCONNECT_MASK;
+		udc->write_fn(udc->base_address, XUSB_IER_OFFSET, intrreg);
+
+		udc->usb_state = 0;
+
+		if (udc->driver->resume) {
+			spin_unlock(&udc->lock);
+			udc->driver->resume(&udc->gadget);
+			spin_lock(&udc->lock);
+		}
+	}
+	if (intrstatus & XUSB_STATUS_DISCONNECT_MASK) {
+
+		dev_dbg(udc->dev, "Disconnect\n");
+
+		/* Enable the reset, resume and suspend */
+		intrreg = udc->read_fn(udc->base_address + XUSB_IER_OFFSET);
+		intrreg |= XUSB_STATUS_RESET_MASK | XUSB_STATUS_RESUME_MASK |
+				 XUSB_STATUS_SUSPEND_MASK;
+		udc->write_fn(udc->base_address, XUSB_IER_OFFSET, intrreg);
+
+		if (udc->driver && udc->driver->disconnect) {
+			spin_unlock(&udc->lock);
+			udc->driver->disconnect(&udc->gadget);
+			spin_lock(&udc->lock);
+		}
+	}
+}
+
+/**
+ * xudc_ep0_stall - Stall endpoint zero.
+ * @udc: pointer to the udc structure.
+ *
+ * This function stalls endpoint zero.
+ */
+static void xudc_ep0_stall(struct xusb_udc *udc)
+{
+	u32 epcfgreg;
+	struct xusb_ep *ep0 = &udc->ep[XUSB_EP_NUMBER_ZERO];
+
+	epcfgreg = udc->read_fn(udc->base_address + ep0->offset);
+	epcfgreg |= XUSB_EP_CFG_STALL_MASK;
+	udc->write_fn(udc->base_address, ep0->offset, epcfgreg);
+}
+
+/**
+ * xudc_setaddress - executes SET_ADDRESS command
+ * @udc: pointer to the udc structure.
+ *
+ * This function executes USB SET_ADDRESS command
+ */
+static void xudc_setaddress(struct xusb_udc *udc)
+{
+	struct xusb_ep *ep0	= &udc->ep[0];
+	struct xusb_req *req	= udc->req;
+	int ret;
+
+	req->usb_req.length = 0;
+	ret = __xudc_ep0_queue(ep0, req);
+	if (ret == 0)
+		return;
+
+	dev_err(udc->dev, "Can't respond to SET ADDRESS request\n");
+	xudc_ep0_stall(udc);
+}
+
+/**
+ * xudc_getstatus - executes GET_STATUS command
+ * @udc: pointer to the udc structure.
+ *
+ * This function executes USB GET_STATUS command
+ */
+static void xudc_getstatus(struct xusb_udc *udc)
+{
+	struct xusb_ep *ep0	= &udc->ep[0];
+	struct xusb_req *req	= udc->req;
+	struct xusb_ep *target_ep;
+	u16 status = 0;
+	u32 epcfgreg;
+	int epnum;
+	u32 halt;
+	int ret;
+
+	switch (udc->setup.bRequestType & USB_RECIP_MASK) {
+	case USB_RECIP_DEVICE:
+		/* Get device status */
+		status = 1 << USB_DEVICE_SELF_POWERED;
+		if (udc->remote_wkp)
+			status |= (1 << USB_DEVICE_REMOTE_WAKEUP);
+		break;
+	case USB_RECIP_INTERFACE:
+		break;
+	case USB_RECIP_ENDPOINT:
+		epnum = udc->setup.wIndex & USB_ENDPOINT_NUMBER_MASK;
+		target_ep = &udc->ep[epnum];
+		epcfgreg = udc->read_fn(udc->base_address + target_ep->offset);
+		halt = epcfgreg & XUSB_EP_CFG_STALL_MASK;
+		if (udc->setup.wIndex & USB_DIR_IN) {
+			if (!target_ep->is_in)
+				goto stall;
+		} else {
+			if (target_ep->is_in)
+				goto stall;
+		}
+		if (halt)
+			status = 1 << USB_ENDPOINT_HALT;
+		break;
+	default:
+		goto stall;
+	}
+
+	req->usb_req.length = 2;
+	*(u16 *)req->usb_req.buf = cpu_to_le16(status);
+	ret = __xudc_ep0_queue(ep0, req);
+	if (ret == 0)
+		return;
+stall:
+	dev_err(udc->dev, "Can't respond to getstatus request\n");
+	xudc_ep0_stall(udc);
+}
+
+/**
+ * xudc_set_clear_feature - Executes the set feature and clear feature commands.
+ * @udc: pointer to the usb device controller structure.
+ *
+ * Processes the SET_FEATURE and CLEAR_FEATURE commands.
+ */
+static void xudc_set_clear_feature(struct xusb_udc *udc)
+{
+	struct xusb_ep *ep0	= &udc->ep[0];
+	struct xusb_req *req	= udc->req;
+	struct xusb_ep *target_ep;
+	u8 endpoint;
+	u8 outinbit;
+	u32 epcfgreg;
+	int flag = (udc->setup.bRequest == USB_REQ_SET_FEATURE ? 1 : 0);
+	int ret;
+
+	switch (udc->setup.bRequestType) {
+	case USB_RECIP_DEVICE:
+		switch (udc->setup.wValue) {
+		case USB_DEVICE_TEST_MODE:
+			/*
+			 * The Test Mode will be executed
+			 * after the status phase.
+			 */
+			break;
+		case USB_DEVICE_REMOTE_WAKEUP:
+			if (flag)
+				udc->remote_wkp = 1;
+			else
+				udc->remote_wkp = 0;
+			break;
+		default:
+			xudc_ep0_stall(udc);
+			break;
+		}
+		break;
+	case USB_RECIP_ENDPOINT:
+		if (!udc->setup.wValue) {
+			endpoint = udc->setup.wIndex &
+					USB_ENDPOINT_NUMBER_MASK;
+			target_ep = &udc->ep[endpoint];
+			outinbit = udc->setup.wIndex &
+					USB_ENDPOINT_DIR_MASK;
+			outinbit = outinbit >> 7;
+
+			/* Make sure direction matches.*/
+			if (outinbit != target_ep->is_in) {
+				xudc_ep0_stall(udc);
+				return;
+			}
+			epcfgreg = udc->read_fn(udc->base_address +
+						target_ep->offset);
+			if (!endpoint) {
+				/* Clear the stall.*/
+				epcfgreg &= ~XUSB_EP_CFG_STALL_MASK;
+				udc->write_fn(udc->base_address,
+						target_ep->offset, epcfgreg);
+			} else {
+				if (flag) {
+					epcfgreg |= XUSB_EP_CFG_STALL_MASK;
+					udc->write_fn(udc->base_address,
+							target_ep->offset,
+							epcfgreg);
+				} else {
+					/* Unstall the endpoint.*/
+					epcfgreg &= ~(XUSB_EP_CFG_STALL_MASK |
+						  XUSB_EP_CFG_DATA_TOGGLE_MASK);
+					udc->write_fn(udc->base_address,
+							target_ep->offset,
+							epcfgreg);
+				}
+			}
+		}
+		break;
+	default:
+		xudc_ep0_stall(udc);
+		return;
+	}
+
+	req->usb_req.length = 0;
+	ret = __xudc_ep0_queue(ep0, req);
+	if (ret == 0)
+		return;
+
+	dev_err(udc->dev, "Can't respond to SET/CLEAR FEATURE\n");
+	xudc_ep0_stall(udc);
+}
+
+/**
+ * xudc_handle_setup - Processes the setup packet.
+ * @udc: pointer to the usb device controller structure.
+ *
+ * Process setup packet and delegate to gadget layer.
+ */
+static void xudc_handle_setup(struct xusb_udc *udc)
+{
+	struct xusb_ep *ep0 = &udc->ep[0];
+	struct usb_ctrlrequest setup;
+	u32 *ep0rambase;
+
+	/* Load up the chapter 9 command buffer.*/
+	ep0rambase = (u32 __force *) (udc->base_address +
+				  XUSB_SETUP_PKT_ADDR_OFFSET);
+	memcpy((void *)&setup, (void *)ep0rambase, 8);
+
+	udc->setup = setup;
+
+	udc->setup.wValue = cpu_to_le16(setup.wValue);
+	udc->setup.wIndex = cpu_to_le16(setup.wIndex);
+	udc->setup.wLength = cpu_to_le16(setup.wLength);
+
+	/* Clear previous requests */
+	xudc_nuke(ep0, -ECONNRESET);
+
+	if (udc->setup.bRequestType & USB_DIR_IN) {
+		/* Execute the get command.*/
+		udc->setupseqrx = STATUS_PHASE;
+		udc->setupseqtx = DATA_PHASE;
+	} else {
+		/* Execute the put command.*/
+		udc->setupseqrx = DATA_PHASE;
+		udc->setupseqtx = STATUS_PHASE;
+	}
+
+	switch (udc->setup.bRequest) {
+	case USB_REQ_GET_STATUS:
+		/* Data+Status phase form udc */
+		if ((udc->setup.bRequestType &
+				(USB_DIR_IN | USB_TYPE_MASK)) !=
+				(USB_DIR_IN | USB_TYPE_STANDARD))
+			break;
+		xudc_getstatus(udc);
+		return;
+	case USB_REQ_SET_ADDRESS:
+		/* Status phase from udc */
+		if (udc->setup.bRequestType != (USB_DIR_OUT |
+				USB_TYPE_STANDARD | USB_RECIP_DEVICE))
+			break;
+		xudc_setaddress(udc);
+		return;
+	case USB_REQ_CLEAR_FEATURE:
+	case USB_REQ_SET_FEATURE:
+		/* Requests with no data phase, status phase from udc */
+		if ((udc->setup.bRequestType & USB_TYPE_MASK)
+				!= USB_TYPE_STANDARD)
+			break;
+		xudc_set_clear_feature(udc);
+		return;
+	default:
+		break;
+	}
+
+	spin_unlock(&udc->lock);
+	if (udc->driver->setup(&udc->gadget, &setup) < 0)
+		xudc_ep0_stall(udc);
+	spin_lock(&udc->lock);
+}
+
+/**
+ * xudc_ep0_out - Processes the endpoint 0 OUT token.
+ * @udc: pointer to the usb device controller structure.
+ */
+static void xudc_ep0_out(struct xusb_udc *udc)
+{
+	struct xusb_ep *ep0 = &udc->ep[0];
+	struct xusb_req *req;
+	u8 *ep0rambase;
+	unsigned int bytes_to_rx;
+	void *buffer;
+
+	req = list_first_entry(&ep0->queue, struct xusb_req, queue);
+
+	switch (udc->setupseqrx) {
+	case STATUS_PHASE:
+		/*
+		 * This resets both state machines for the next
+		 * Setup packet.
+		 */
+		udc->setupseqrx = SETUP_PHASE;
+		udc->setupseqtx = SETUP_PHASE;
+		req->usb_req.actual = req->usb_req.length;
+		xudc_done(ep0, req, 0);
+		break;
+	case DATA_PHASE:
+		bytes_to_rx = udc->read_fn(udc->base_address +
+				XUSB_EP_BUF0COUNT_OFFSET);
+		/* Copy the data to be received from the DPRAM. */
+		ep0rambase = (u8 __force *) (udc->base_address +
+				(ep0->rambase << 2));
+
+		buffer = req->usb_req.buf + req->usb_req.actual;
+		req->usb_req.actual = req->usb_req.actual + bytes_to_rx;
+		memcpy(buffer, (void *)ep0rambase, bytes_to_rx);
+
+		if (req->usb_req.length == req->usb_req.actual) {
+			/* Data transfer completed get ready for Status stage */
+			xudc_wrstatus(udc);
+		} else {
+			/* Enable EP0 buffer to receive data */
+			udc->write_fn(udc->base_address,
+					XUSB_EP_BUF0COUNT_OFFSET, 0);
+			udc->write_fn(udc->base_address,
+					XUSB_BUFFREADY_OFFSET, 1);
+		}
+		break;
+	default:
+		break;
+	}
+}
+
+/**
+ * xudc_ep0_in - Processes the endpoint 0 IN token.
+ * @udc: pointer to the usb device controller structure.
+ */
+static void xudc_ep0_in(struct xusb_udc *udc)
+{
+	struct xusb_ep *ep0 = &udc->ep[0];
+	struct xusb_req *req;
+	unsigned int bytes_to_tx;
+	void *buffer;
+	u32 epcfgreg;
+	u16 count = 0;
+	u16 length;
+	u8 *ep0rambase;
+	u8 test_mode = udc->setup.wIndex >> 8;
+
+	req = list_first_entry(&ep0->queue, struct xusb_req, queue);
+	bytes_to_tx = req->usb_req.length - req->usb_req.actual;
+
+	switch (udc->setupseqtx) {
+	case STATUS_PHASE:
+		switch (udc->setup.bRequest) {
+		case USB_REQ_SET_ADDRESS:
+			/* Set the address of the device.*/
+			udc->write_fn(udc->base_address,
+					XUSB_ADDRESS_OFFSET,
+					udc->setup.wValue);
+			break;
+		case USB_REQ_SET_FEATURE:
+			if (udc->setup.bRequestType ==
+					USB_RECIP_DEVICE) {
+				if (udc->setup.wValue ==
+						USB_DEVICE_TEST_MODE)
+					udc->write_fn(udc->base_address,
+							XUSB_TESTMODE_OFFSET,
+							test_mode);
+			}
+			break;
+		}
+		req->usb_req.actual = req->usb_req.length;
+		xudc_done(ep0, req, 0);
+		break;
+	case DATA_PHASE:
+		if (!bytes_to_tx) {
+			/*
+			 * We're done with data transfer, next
+			 * will be zero length OUT with data toggle of
+			 * 1. Setup data_toggle.
+			 */
+			epcfgreg = udc->read_fn(udc->base_address +
+					ep0->offset);
+			epcfgreg |= XUSB_EP_CFG_DATA_TOGGLE_MASK;
+			udc->write_fn(udc->base_address, ep0->offset, epcfgreg);
+			udc->setupseqtx = STATUS_PHASE;
+		} else {
+			length = count = min_t(u32, bytes_to_tx,
+						EP0_MAX_PACKET);
+			/* Copy the data to be transmitted into the DPRAM. */
+			ep0rambase = (u8 __force *) (udc->base_address +
+					(ep0->rambase << 2));
+
+			buffer = req->usb_req.buf + req->usb_req.actual;
+			req->usb_req.actual = req->usb_req.actual + length;
+			memcpy((void *)ep0rambase, buffer, length);
+		}
+		udc->write_fn(udc->base_address, XUSB_EP_BUF0COUNT_OFFSET,
+				count);
+		udc->write_fn(udc->base_address, XUSB_BUFFREADY_OFFSET, 1);
+		break;
+	default:
+		break;
+	}
+}
+
+/**
+ * xudc_ctrl_ep_handler - Endpoint 0 interrupt handler.
+ * @udc: pointer to the udc structure.
+ * @intrstatus:	It's the mask value for the interrupt sources on endpoint 0.
+ *
+ * Processes the commands received during enumeration phase.
+ */
+static void xudc_ctrl_ep_handler(struct xusb_udc *udc, u32 intrstatus)
+{
+
+	if (intrstatus & XUSB_STATUS_SETUP_PACKET_MASK) {
+		xudc_handle_setup(udc);
+	} else {
+		if (intrstatus & XUSB_STATUS_FIFO_BUFF_RDY_MASK)
+			xudc_ep0_out(udc);
+		else if (intrstatus & XUSB_STATUS_FIFO_BUFF_FREE_MASK)
+			xudc_ep0_in(udc);
+	}
+}
+
+/**
+ * xudc_nonctrl_ep_handler - Non control endpoint interrupt handler.
+ * @udc: pointer to the udc structure.
+ * @epnum: End point number for which the interrupt is to be processed
+ * @intrstatus:	mask value for interrupt sources of endpoints other
+ *		than endpoint 0.
+ *
+ * Processes the buffer completion interrupts.
+ */
+static void xudc_nonctrl_ep_handler(struct xusb_udc *udc, u8 epnum,
+		u32 intrstatus)
+{
+
+	struct xusb_req *req;
+	struct xusb_ep *ep;
+
+	ep = &udc->ep[epnum];
+	/* Process the End point interrupts.*/
+	if (intrstatus & (XUSB_STATUS_EP0_BUFF1_COMP_MASK << epnum))
+		ep->buffer0ready = 0;
+	if (intrstatus & (XUSB_STATUS_EP0_BUFF2_COMP_MASK << epnum))
+		ep->buffer1ready = 0;
+
+	if (list_empty(&ep->queue))
+		return;
+
+	req = list_first_entry(&ep->queue, struct xusb_req, queue);
+
+	if (ep->is_in)
+		xudc_write_fifo(ep, req);
+	else
+		xudc_read_fifo(ep, req);
+}
+
+/**
+ * xudc_irq - The main interrupt handler.
+ * @irq: The interrupt number.
+ * @_udc: pointer to the usb device controller structure.
+ *
+ * Return: IRQ_HANDLED after the interrupt is handled.
+ */
+static irqreturn_t xudc_irq(int irq, void *_udc)
+{
+	struct xusb_udc *udc = _udc;
+	u32 intrstatus;
+	u32 ier;
+	u8 index;
+	u32 bufintr;
+	unsigned long flags;
+
+	spin_lock_irqsave(&udc->lock, flags);
+
+	/*
+	 * Event interrupts are level sensitive hence first disable
+	 * IER, read ISR and figure out active interrupts.
+	 */
+	ier = udc->read_fn(udc->base_address + XUSB_IER_OFFSET);
+	ier &= ~XUSB_STATUS_INTR_EVENT_MASK;
+	udc->write_fn(udc->base_address, XUSB_IER_OFFSET, ier);
+
+	/* Read the Interrupt Status Register.*/
+	intrstatus = udc->read_fn(udc->base_address + XUSB_STATUS_OFFSET);
+
+	/* Call the handler for the event interrupt.*/
+	if (intrstatus & XUSB_STATUS_INTR_EVENT_MASK) {
+		/*
+		 * Check if there is any action to be done for :
+		 * - USB Reset received {XUSB_STATUS_RESET_MASK}
+		 * - USB Suspend received {XUSB_STATUS_SUSPEND_MASK}
+		 * - USB Resume received {XUSB_STATUS_RESUME_MASK}
+		 * - USB Disconnect received {XUSB_STATUS_DISCONNECT_MASK}
+		 */
+		xudc_startup_handler(udc, intrstatus);
+	}
+
+	/* Check the buffer completion interrupts */
+	if (intrstatus & XUSB_STATUS_INTR_BUFF_COMP_ALL_MASK) {
+		/* Enable Reset, Suspend, Resume and Disconnect  */
+		ier = udc->read_fn(udc->base_address + XUSB_IER_OFFSET);
+		ier |= XUSB_STATUS_INTR_EVENT_MASK;
+		udc->write_fn(udc->base_address, XUSB_IER_OFFSET, ier);
+
+		if (intrstatus & XUSB_STATUS_EP0_BUFF1_COMP_MASK)
+			xudc_ctrl_ep_handler(udc, intrstatus);
+
+		for (index = 1; index < 8; index++) {
+			bufintr = ((intrstatus &
+					(XUSB_STATUS_EP1_BUFF1_COMP_MASK <<
+							(index - 1))) ||
+				   (intrstatus &
+					(XUSB_STATUS_EP1_BUFF2_COMP_MASK <<
+							(index - 1))));
+			if (bufintr) {
+				xudc_nonctrl_ep_handler(udc, index,
+						intrstatus);
+			}
+		}
+	}
+
+	spin_unlock_irqrestore(&udc->lock, flags);
+	return IRQ_HANDLED;
+}
+
+/**
+ * xudc_probe - The device probe function for driver initialization.
+ * @pdev: pointer to the platform device structure.
+ *
+ * Return: 0 for success and error value on failure
+ */
+static int xudc_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct resource *res;
+	struct xusb_udc *udc;
+	struct xusb_ep *ep0;
+	int irq;
+	int ret;
+	u32 ier;
+	u8 *buff;
+
+	udc = devm_kzalloc(&pdev->dev, sizeof(*udc), GFP_KERNEL);
+	if (!udc)
+		return -ENOMEM;
+
+	/* Map the registers */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	udc->base_address = devm_ioremap_resource(&pdev->dev, res);
+	if (!udc->base_address)
+		return -ENOMEM;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(&pdev->dev, "unable to get irq\n");
+		return irq;
+	}
+	ret = devm_request_irq(&pdev->dev, irq, xudc_irq, 0,
+				dev_name(&pdev->dev), udc);
+	if (ret < 0) {
+		dev_dbg(&pdev->dev, "unable to request irq %d", irq);
+		goto fail;
+	}
+
+	udc->dma_enabled = of_property_read_bool(np, "xlnx,has-builtin-dma");
+
+	/* Setup gadget structure */
+	udc->gadget.ops = &xusb_udc_ops;
+	udc->gadget.max_speed = USB_SPEED_HIGH;
+	udc->gadget.speed = USB_SPEED_UNKNOWN;
+	udc->gadget.ep0 = &udc->ep[XUSB_EP_NUMBER_ZERO].ep_usb;
+	udc->gadget.name = driver_name;
+
+	spin_lock_init(&udc->lock);
+
+	/* Check for IP endianness */
+	udc->write_fn = xudc_write32_be;
+	udc->read_fn = xudc_read32_be;
+	udc->write_fn(udc->base_address, XUSB_TESTMODE_OFFSET, TEST_J);
+	if ((udc->read_fn(udc->base_address + XUSB_TESTMODE_OFFSET))
+			!= TEST_J) {
+		udc->write_fn = xudc_write32;
+		udc->read_fn = xudc_read32;
+	}
+	udc->write_fn(udc->base_address, XUSB_TESTMODE_OFFSET, 0);
+
+	xudc_eps_init(udc);
+
+	ep0 = &udc->ep[0];
+	/* Create a dummy request for GET_STATUS, SET_ADDRESS */
+	udc->req = container_of(xudc_ep_alloc_request(&ep0->ep_usb, GFP_KERNEL),
+				struct xusb_req, usb_req);
+	if (!udc->req) {
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	/* buffer for data of get_status request */
+	buff = kzalloc(2, GFP_KERNEL);
+	if (buff == NULL) {
+		ret = -ENOMEM;
+		goto fail;
+	}
+	/* Dummy request ready, free this in remove */
+	udc->req->usb_req.buf = buff;
+
+	/* Set device address to 0.*/
+	udc->write_fn(udc->base_address, XUSB_ADDRESS_OFFSET, 0);
+
+	ret = usb_add_gadget_udc(&pdev->dev, &udc->gadget);
+	if (ret)
+		goto fail;
+
+	udc->dev = &udc->gadget.dev;
+
+	/* Enable the interrupts.*/
+	ier = XUSB_STATUS_GLOBAL_INTR_MASK | XUSB_STATUS_INTR_EVENT_MASK |
+		XUSB_STATUS_FIFO_BUFF_RDY_MASK |
+		XUSB_STATUS_FIFO_BUFF_FREE_MASK |
+		XUSB_STATUS_SETUP_PACKET_MASK |
+		XUSB_STATUS_INTR_BUFF_COMP_ALL_MASK;
+
+	udc->write_fn(udc->base_address, XUSB_IER_OFFSET, ier);
+
+	platform_set_drvdata(pdev, udc);
+
+	dev_dbg(&pdev->dev, "%s at 0x%08X mapped to 0x%08X %s\n",
+		driver_name, (u32)res->start,
+		(u32 __force)udc->base_address,
+		udc->dma_enabled ? "with DMA" : "without DMA");
+
+	return 0;
+fail:
+	dev_err(&pdev->dev, "probe failed, %d\n", ret);
+	return ret;
+}
+
+/**
+ * xudc_remove - Releases the resources allocated during the initialization.
+ * @pdev: pointer to the platform device structure.
+ *
+ * Return: 0 always
+ */
+static int xudc_remove(struct platform_device *pdev)
+{
+	struct xusb_udc *udc = platform_get_drvdata(pdev);
+	void *buf = udc->req->usb_req.buf;
+
+	usb_del_gadget_udc(&udc->gadget);
+
+	/* free memory allocated for dummy request buffer */
+	kfree(buf);
+	/* free memory allocated for dummy request */
+	kfree(udc->req);
+
+	return 0;
+}
+
+/* Match table for of_platform binding */
+static const struct of_device_id usb_of_match[] = {
+	{ .compatible = "xlnx,usb2-device-4.00.a", },
+	{ /* end of list */ },
+};
+MODULE_DEVICE_TABLE(of, usb_of_match);
+
+static struct platform_driver xudc_driver = {
+	.driver = {
+		.name = driver_name,
+		.owner = THIS_MODULE,
+		.of_match_table = usb_of_match,
+	},
+	.probe = xudc_probe,
+	.remove = xudc_remove,
+};
+
+module_platform_driver(xudc_driver);
+
+MODULE_DESCRIPTION("Xilinx udc driver");
+MODULE_AUTHOR("Xilinx, Inc");
+MODULE_LICENSE("GPL");
-- 
1.7.4


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Re: [PATCH v4 2/2] usb: gadget: Add xilinx usb2 device support

[Varka Bhadram]

On 07/22/2014 02:38 PM, Subbaraya Sundeep Bhatta wrote:
> +#include <linux/delay.h>
> +#include <linux/device.h>
> +#include <linux/dma-mapping.h>
> +#include "gadget_chips.h"
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of_address.h>
> +#include <linux/of_device.h>
> +#include <linux/of_platform.h>
> +#include <linux/of_irq.h>
> +#include <linux/prefetch.h>
> +#include <linux/usb/ch9.h>
> +#include <linux/usb/gadget.h>
> +

Normally we will put the includes in alphabetical because it looks good
and readable.

But we have to include the local headers separately after all the main includes...
#include <linux/delay.h>
#include <linux/device.h>
....
#include <linux/usb/gadget.h>

#include "gadget_chips.h"

(...)

>
> +	switch (udc->setupseqtx) {
> +	case STATUS_PHASE:
> +		switch (udc->setup.bRequest) {
> +		case USB_REQ_SET_ADDRESS:
> +			/* Set the address of the device.*/
> +			udc->write_fn(udc->base_address,
> +					XUSB_ADDRESS_OFFSET,
> +					udc->setup.wValue);

Should match open parenthesis

udc->write_fn(udc->base_address,
	      XUSB_ADDRESS_OFFSET,
	      udc->setup.wValue);


> +			break;
> +		case USB_REQ_SET_FEATURE:
> +			if (udc->setup.bRequestType ==
> +					USB_RECIP_DEVICE) {
> +				if (udc->setup.wValue ==
> +						USB_DEVICE_TEST_MODE)
> +					udc->write_fn(udc->base_address,
> +							XUSB_TESTMODE_OFFSET,
> +							test_mode);

Dto

> +			}
> +			break;
> +		}
> +		req->usb_req.actual = req->usb_req.length;
> +		xudc_done(ep0, req, 0);
> +		break;
> +	case DATA_PHASE:
> +		if (!bytes_to_tx) {
> +			/*
> +			 * We're done with data transfer, next
> +			 * will be zero length OUT with data toggle of
> +			 * 1. Setup data_toggle.
> +			 */
> +			epcfgreg = udc->read_fn(udc->base_address +
> +					ep0->offset);
> +			epcfgreg |= XUSB_EP_CFG_DATA_TOGGLE_MASK;
> +			udc->write_fn(udc->base_address, ep0->offset, epcfgreg);
> +			udc->setupseqtx = STATUS_PHASE;
> +		} else {
> +			length = count = min_t(u32, bytes_to_tx,
> +						EP0_MAX_PACKET);
> +			/* Copy the data to be transmitted into the DPRAM. */
> +			ep0rambase = (u8 __force *) (udc->base_address +
> +					(ep0->rambase << 2));
> +
> +			buffer = req->usb_req.buf + req->usb_req.actual;
> +			req->usb_req.actual = req->usb_req.actual + length;
> +			memcpy((void *)ep0rambase, buffer, length);
> +		}
> +		udc->write_fn(udc->base_address, XUSB_EP_BUF0COUNT_OFFSET,
> +				count);
> +		udc->write_fn(udc->base_address, XUSB_BUFFREADY_OFFSET, 1);
> +		break;
> +	default:
> +		break;
> +	}
> +}
> +
> +/**
> + * xudc_ctrl_ep_handler - Endpoint 0 interrupt handler.
> + * @udc: pointer to the udc structure.
> + * @intrstatus:	It's the mask value for the interrupt sources on endpoint 0.
> + *
> + * Processes the commands received during enumeration phase.
> + */
> +static void xudc_ctrl_ep_handler(struct xusb_udc *udc, u32 intrstatus)
> +{
> +
> +	if (intrstatus & XUSB_STATUS_SETUP_PACKET_MASK) {
> +		xudc_handle_setup(udc);
> +	} else {
> +		if (intrstatus & XUSB_STATUS_FIFO_BUFF_RDY_MASK)
> +			xudc_ep0_out(udc);
> +		else if (intrstatus & XUSB_STATUS_FIFO_BUFF_FREE_MASK)
> +			xudc_ep0_in(udc);
> +	}
> +}
> +
> +/**
> + * xudc_nonctrl_ep_handler - Non control endpoint interrupt handler.
> + * @udc: pointer to the udc structure.
> + * @epnum: End point number for which the interrupt is to be processed
> + * @intrstatus:	mask value for interrupt sources of endpoints other
> + *		than endpoint 0.
> + *
> + * Processes the buffer completion interrupts.
> + */
> +static void xudc_nonctrl_ep_handler(struct xusb_udc *udc, u8 epnum,
> +		u32 intrstatus)

Should match open parenthesis:

static void xudc_nonctrl_ep_handler(struct xusb_udc *udc, u8 epnum,
				    u32 intrstatus)

> +{
> +
> +	struct xusb_req *req;
> +	struct xusb_ep *ep;
> +
> +	ep = &udc->ep[epnum];
> +	/* Process the End point interrupts.*/
> +	if (intrstatus & (XUSB_STATUS_EP0_BUFF1_COMP_MASK << epnum))
> +		ep->buffer0ready = 0;
> +	if (intrstatus & (XUSB_STATUS_EP0_BUFF2_COMP_MASK << epnum))
> +		ep->buffer1ready = 0;
> +
> +	if (list_empty(&ep->queue))
> +		return;
> +
> +	req = list_first_entry(&ep->queue, struct xusb_req, queue);
> +
> +	if (ep->is_in)
> +		xudc_write_fifo(ep, req);
> +	else
> +		xudc_read_fifo(ep, req);
> +}
> +

(...)

> +
> +	/* buffer for data of get_status request */
> +	buff = kzalloc(2, GFP_KERNEL);

define proper macro for '2'. Also we can use devm_kzalloc().

Also one more thing: if we use kzalloc for allocating the 2 bytes
no where i found that releasing the buffer on error path.

> +	if (buff == NULL) {
> +		ret = -ENOMEM;
> +		goto fail;
> +	}
> +	/* Dummy request ready, free this in remove */
> +	udc->req->usb_req.buf = buff;
> +
> +	/* Set device address to 0.*/
> +	udc->write_fn(udc->base_address, XUSB_ADDRESS_OFFSET, 0);
> +
> +	ret = usb_add_gadget_udc(&pdev->dev, &udc->gadget);
> +	if (ret)
> +		goto fail;

If it fails we have to free the buff. see above..

> +
> +	udc->dev = &udc->gadget.dev;
> +
> +	/* Enable the interrupts.*/
> +	ier = XUSB_STATUS_GLOBAL_INTR_MASK | XUSB_STATUS_INTR_EVENT_MASK |
> +		XUSB_STATUS_FIFO_BUFF_RDY_MASK |
> +		XUSB_STATUS_FIFO_BUFF_FREE_MASK |
> +		XUSB_STATUS_SETUP_PACKET_MASK |
> +		XUSB_STATUS_INTR_BUFF_COMP_ALL_MASK;
> +
> +	udc->write_fn(udc->base_address, XUSB_IER_OFFSET, ier);
> +
> +	platform_set_drvdata(pdev, udc);
> +
> +	dev_dbg(&pdev->dev, "%s at 0x%08X mapped to 0x%08X %s\n",
> +		driver_name, (u32)res->start,
> +		(u32 __force)udc->base_address,
> +		udc->dma_enabled ? "with DMA" : "without DMA");
> +
> +	return 0;
> +fail:
> +	dev_err(&pdev->dev, "probe failed, %d\n", ret);
> +	return ret;
> +}
> +
> +/**
> + * xudc_remove - Releases the resources allocated during the initialization.
> + * @pdev: pointer to the platform device structure.
> + *
> + * Return: 0 always
> + */
> +static int xudc_remove(struct platform_device *pdev)
> +{
> +	struct xusb_udc *udc = platform_get_drvdata(pdev);
> +	void *buf = udc->req->usb_req.buf;

No need of creating another "void *". We can directly free it. (It is u8 *)

> +
> +	usb_del_gadget_udc(&udc->gadget);
> +
> +	/* free memory allocated for dummy request buffer */
> +	kfree(buf);
> +	/* free memory allocated for dummy request */
> +	kfree(udc->req);
> +
> +	return 0;
> +}
> +
> +/* Match table for of_platform binding */
> +static const struct of_device_id usb_of_match[] = {
> +	{ .compatible = "xlnx,usb2-device-4.00.a", },
> +	{ /* end of list */ },
> +};
> +MODULE_DEVICE_TABLE(of, usb_of_match);
> +
> +static struct platform_driver xudc_driver = {
> +	.driver = {
> +		.name = driver_name,
> +		.owner = THIS_MODULE,

We can drop the owner field update... It updated automatically
by module_platform_driver().


Please run checkpatch.pl on this patch. You may get more warnings and errors.


-- 
Regards,
Varka Bhadram.

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Re: [PATCH v4 2/2] usb: gadget: Add xilinx usb2 device support

[sundeep subbaraya]

Hi,

On Tue, Jul 22, 2014 at 3:32 PM, Varka Bhadram <varkabhadram-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> On 07/22/2014 02:38 PM, Subbaraya Sundeep Bhatta wrote:
>>
>> +#include <linux/delay.h>
>> +#include <linux/device.h>
>> +#include <linux/dma-mapping.h>
>> +#include "gadget_chips.h"
>> +#include <linux/interrupt.h>
>> +#include <linux/io.h>
>> +#include <linux/module.h>
>> +#include <linux/of_address.h>
>> +#include <linux/of_device.h>
>> +#include <linux/of_platform.h>
>> +#include <linux/of_irq.h>
>> +#include <linux/prefetch.h>
>> +#include <linux/usb/ch9.h>
>> +#include <linux/usb/gadget.h>
>> +
>
>
> Normally we will put the includes in alphabetical because it looks good
> and readable.
>
> But we have to include the local headers separately after all the main
> includes...
> #include <linux/delay.h>
> #include <linux/device.h>
> ....
> #include <linux/usb/gadget.h>
>
> #include "gadget_chips.h"
>
> (...)
>
Ok
>
>>
>> +       switch (udc->setupseqtx) {
>> +       case STATUS_PHASE:
>> +               switch (udc->setup.bRequest) {
>> +               case USB_REQ_SET_ADDRESS:
>> +                       /* Set the address of the device.*/
>> +                       udc->write_fn(udc->base_address,
>> +                                       XUSB_ADDRESS_OFFSET,
>> +                                       udc->setup.wValue);
>
>
> Should match open parenthesis
not necessary, as per coding style spaces should not be used --
Outside of comments, documentation and except in Kconfig, spaces are never
used for indentation.

>
> udc->write_fn(udc->base_address,
>               XUSB_ADDRESS_OFFSET,
>
>               udc->setup.wValue);
>
>
>> +                       break;
>> +               case USB_REQ_SET_FEATURE:
>> +                       if (udc->setup.bRequestType ==
>> +                                       USB_RECIP_DEVICE) {
>> +                               if (udc->setup.wValue ==
>> +                                               USB_DEVICE_TEST_MODE)
>> +                                       udc->write_fn(udc->base_address,
>> +
>> XUSB_TESTMODE_OFFSET,
>> +                                                       test_mode);
>
>
> Dto
not necessary
>
>
>> +                       }
>> +                       break;
>> +               }
>> +               req->usb_req.actual = req->usb_req.length;
>> +               xudc_done(ep0, req, 0);
>> +               break;
>> +       case DATA_PHASE:
>> +               if (!bytes_to_tx) {
>> +                       /*
>> +                        * We're done with data transfer, next
>> +                        * will be zero length OUT with data toggle of
>> +                        * 1. Setup data_toggle.
>> +                        */
>> +                       epcfgreg = udc->read_fn(udc->base_address +
>> +                                       ep0->offset);
>> +                       epcfgreg |= XUSB_EP_CFG_DATA_TOGGLE_MASK;
>> +                       udc->write_fn(udc->base_address, ep0->offset,
>> epcfgreg);
>> +                       udc->setupseqtx = STATUS_PHASE;
>> +               } else {
>> +                       length = count = min_t(u32, bytes_to_tx,
>> +                                               EP0_MAX_PACKET);
>> +                       /* Copy the data to be transmitted into the DPRAM.
>> */
>> +                       ep0rambase = (u8 __force *) (udc->base_address +
>> +                                       (ep0->rambase << 2));
>> +
>> +                       buffer = req->usb_req.buf + req->usb_req.actual;
>> +                       req->usb_req.actual = req->usb_req.actual +
>> length;
>> +                       memcpy((void *)ep0rambase, buffer, length);
>> +               }
>> +               udc->write_fn(udc->base_address, XUSB_EP_BUF0COUNT_OFFSET,
>> +                               count);
>> +               udc->write_fn(udc->base_address, XUSB_BUFFREADY_OFFSET,
>> 1);
>> +               break;
>> +       default:
>> +               break;
>> +       }
>> +}
>> +
>> +/**
>> + * xudc_ctrl_ep_handler - Endpoint 0 interrupt handler.
>> + * @udc: pointer to the udc structure.
>> + * @intrstatus:        It's the mask value for the interrupt sources on
>> endpoint 0.
>> + *
>> + * Processes the commands received during enumeration phase.
>> + */
>> +static void xudc_ctrl_ep_handler(struct xusb_udc *udc, u32 intrstatus)
>> +{
>> +
>> +       if (intrstatus & XUSB_STATUS_SETUP_PACKET_MASK) {
>> +               xudc_handle_setup(udc);
>> +       } else {
>> +               if (intrstatus & XUSB_STATUS_FIFO_BUFF_RDY_MASK)
>> +                       xudc_ep0_out(udc);
>> +               else if (intrstatus & XUSB_STATUS_FIFO_BUFF_FREE_MASK)
>> +                       xudc_ep0_in(udc);
>> +       }
>> +}
>> +
>> +/**
>> + * xudc_nonctrl_ep_handler - Non control endpoint interrupt handler.
>> + * @udc: pointer to the udc structure.
>> + * @epnum: End point number for which the interrupt is to be processed
>> + * @intrstatus:        mask value for interrupt sources of endpoints
>> other
>> + *             than endpoint 0.
>> + *
>> + * Processes the buffer completion interrupts.
>> + */
>> +static void xudc_nonctrl_ep_handler(struct xusb_udc *udc, u8 epnum,
>> +               u32 intrstatus)
>
>
> Should match open parenthesis:
not necessary
>
>
> static void xudc_nonctrl_ep_handler(struct xusb_udc *udc, u8 epnum,
>                                     u32 intrstatus)
>
>> +{
>> +
>> +       struct xusb_req *req;
>> +       struct xusb_ep *ep;
>> +
>> +       ep = &udc->ep[epnum];
>> +       /* Process the End point interrupts.*/
>> +       if (intrstatus & (XUSB_STATUS_EP0_BUFF1_COMP_MASK << epnum))
>> +               ep->buffer0ready = 0;
>> +       if (intrstatus & (XUSB_STATUS_EP0_BUFF2_COMP_MASK << epnum))
>> +               ep->buffer1ready = 0;
>> +
>> +       if (list_empty(&ep->queue))
>> +               return;
>> +
>> +       req = list_first_entry(&ep->queue, struct xusb_req, queue);
>> +
>> +       if (ep->is_in)
>> +               xudc_write_fifo(ep, req);
>> +       else
>> +               xudc_read_fifo(ep, req);
>> +}
>> +
>
>
> (...)
>
>
>> +
>> +       /* buffer for data of get_status request */
>> +       buff = kzalloc(2, GFP_KERNEL);
>
>
> define proper macro for '2'. Also we can use devm_kzalloc().
Ok
>
> Also one more thing: if we use kzalloc for allocating the 2 bytes
> no where i found that releasing the buffer on error path.
>
>
>> +       if (buff == NULL) {
>> +               ret = -ENOMEM;
>> +               goto fail;
>> +       }
>> +       /* Dummy request ready, free this in remove */
>> +       udc->req->usb_req.buf = buff;
>> +
>> +       /* Set device address to 0.*/
>> +       udc->write_fn(udc->base_address, XUSB_ADDRESS_OFFSET, 0);
>> +
>> +       ret = usb_add_gadget_udc(&pdev->dev, &udc->gadget);
>> +       if (ret)
>> +               goto fail;
>
>
> If it fails we have to free the buff. see above..
Yeah will change.
>
>
>> +
>> +       udc->dev = &udc->gadget.dev;
>> +
>> +       /* Enable the interrupts.*/
>> +       ier = XUSB_STATUS_GLOBAL_INTR_MASK | XUSB_STATUS_INTR_EVENT_MASK |
>> +               XUSB_STATUS_FIFO_BUFF_RDY_MASK |
>> +               XUSB_STATUS_FIFO_BUFF_FREE_MASK |
>> +               XUSB_STATUS_SETUP_PACKET_MASK |
>> +               XUSB_STATUS_INTR_BUFF_COMP_ALL_MASK;
>> +
>> +       udc->write_fn(udc->base_address, XUSB_IER_OFFSET, ier);
>> +
>> +       platform_set_drvdata(pdev, udc);
>> +
>> +       dev_dbg(&pdev->dev, "%s at 0x%08X mapped to 0x%08X %s\n",
>> +               driver_name, (u32)res->start,
>> +               (u32 __force)udc->base_address,
>> +               udc->dma_enabled ? "with DMA" : "without DMA");
>> +
>> +       return 0;
>> +fail:
>> +       dev_err(&pdev->dev, "probe failed, %d\n", ret);
>> +       return ret;
>> +}
>> +
>> +/**
>> + * xudc_remove - Releases the resources allocated during the
>> initialization.
>> + * @pdev: pointer to the platform device structure.
>> + *
>> + * Return: 0 always
>> + */
>> +static int xudc_remove(struct platform_device *pdev)
>> +{
>> +       struct xusb_udc *udc = platform_get_drvdata(pdev);
>> +       void *buf = udc->req->usb_req.buf;
>
>
> No need of creating another "void *". We can directly free it. (It is u8 *)
Ofcourse but as per Felipe's comments declared local variables for readability
>
>
>> +
>> +       usb_del_gadget_udc(&udc->gadget);
>> +
>> +       /* free memory allocated for dummy request buffer */
>> +       kfree(buf);
>> +       /* free memory allocated for dummy request */
>> +       kfree(udc->req);
>> +
>> +       return 0;
>> +}
>> +
>> +/* Match table for of_platform binding */
>> +static const struct of_device_id usb_of_match[] = {
>> +       { .compatible = "xlnx,usb2-device-4.00.a", },
>> +       { /* end of list */ },
>> +};
>> +MODULE_DEVICE_TABLE(of, usb_of_match);
>> +
>> +static struct platform_driver xudc_driver = {
>> +       .driver = {
>> +               .name = driver_name,
>> +               .owner = THIS_MODULE,
>
>
> We can drop the owner field update... It updated automatically
> by module_platform_driver().
Ok
>
>
> Please run checkpatch.pl on this patch. You may get more warnings and
> errors.
Yes ran before sending this out. 0 errors and 0 warnings.

Thanks,
Sundeep.B.S.
>
>
> --
> Regards,
> Varka Bhadram.
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
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Re: [PATCH v4 2/2] usb: gadget: Add xilinx usb2 device support

[Daniel Mack]

Hi,

On 07/22/2014 11:08 AM, Subbaraya Sundeep Bhatta wrote:
> This patch adds xilinx usb2 device driver support

Add some more information here, please. Copying the text from the
Kconfig option is already a good start.

>  drivers/usb/gadget/Kconfig      |   14 +
>  drivers/usb/gadget/Makefile     |    1 +
>  drivers/usb/gadget/udc-xilinx.c | 2261 +++++++++++++++++++++++++++++++++++++++
>  3 files changed, 2276 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/usb/gadget/udc-xilinx.c

As your driver has a DT binding, you have to describe it in
Documentation/devicetree/bindings.

> --- a/drivers/usb/gadget/Kconfig
> +++ b/drivers/usb/gadget/Kconfig
> @@ -459,6 +459,20 @@ config USB_EG20T
>  	  ML7213/ML7831 is companion chip for Intel Atom E6xx series.
>  	  ML7213/ML7831 is completely compatible for Intel EG20T PCH.
>
> +config USB_GADGET_XILINX
> +	tristate "Xilinx USB Driver"
> +	depends on COMPILE_TEST

Why would you depend on that?

Also, your code uses device tree functions unconditionally, which is
fine, but it must hence depend on 'OF'.

> +struct xusb_ep {
> +	struct usb_ep ep_usb;
> +	struct list_head queue;
> +	struct xusb_udc *udc;
> +	const struct usb_endpoint_descriptor *desc;
> +	u32 rambase;
> +	u32 offset;
> +	char name[4];
> +	u16 epnumber;
> +	u16 maxpacket;
> +	u16 buffer0count;
> +	u16 buffer1count;
> +	u8 buffer0ready;
> +	u8 buffer1ready;
> +	u8 eptype;
> +	u8 curbufnum;
> +	u8 is_in;
> +	u8 is_iso;

Some of those could probably become booleans.

> +struct xusb_udc {
> +	struct usb_gadget gadget;
> +	struct xusb_ep ep[8];
> +	struct usb_gadget_driver *driver;
> +	struct usb_ctrlrequest setup;
> +	struct xusb_req *req;
> +	struct device *dev;
> +	u32 usb_state;
> +	u32 remote_wkp;
> +	u32 setupseqtx;
> +	u32 setupseqrx;
> +	void __iomem *base_address;
> +	spinlock_t lock;
> +	bool dma_enabled;
> +
> +	unsigned int (*read_fn)(void __iomem *);
> +	void (*write_fn)(void __iomem *, u32, u32);
> +};
> +
> +/* Endpoint buffer start addresses in the core */
> +static u32 rambase[8] = { 0x22, 0x1000, 0x1100, 0x1200, 0x1300, 0x1400, 0x1500,
> +			0x1600 };

As stated by Peter, indenting such lines to match the position of the
line before makes such code much prettier and more readable. It's also
done in the majority of drivers.

This counts for many locations in your code.

> +/* Control endpoint configuration.*/
> +static const struct usb_endpoint_descriptor config_bulk_out_desc = {
> +	.bLength		= USB_DT_ENDPOINT_SIZE,
> +	.bDescriptorType	= USB_DT_ENDPOINT,
> +	.bEndpointAddress	= USB_DIR_OUT,
> +	.bmAttributes		= USB_ENDPOINT_XFER_BULK,
> +	.wMaxPacketSize		= cpu_to_le16(64),

Why not use EP0_MAX_PACKET here?

> +static void xudc_wrstatus(struct xusb_udc *udc)
> +{
> +	struct xusb_ep *ep0 = &udc->ep[XUSB_EP_NUMBER_ZERO];
> +	u32 epcfgreg;
> +
> +	epcfgreg = udc->read_fn(udc->base_address + ep0->offset)|
> +			XUSB_EP_CFG_DATA_TOGGLE_MASK;
> +	udc->write_fn(udc->base_address, ep0->offset, epcfgreg);
> +	udc->write_fn(udc->base_address, ep0->offset + XUSB_EP_BUF0COUNT_OFFSET,
> +			0);

Just a nit, but renaming 'base_address' to something like 'base' or
'addr' would help you get around or maximum line constraint here and in
some other places.

> +static int xudc_dma_send(struct xusb_ep *ep, struct xusb_req *req,
> +		u8 *buffer, u32 length)
> +{
> +	u32 *eprambase;
> +	dma_addr_t src;
> +	dma_addr_t dst;
> +	int ret;
> +	struct xusb_udc *udc = ep->udc;
> +
> +	src = req->usb_req.dma + req->usb_req.actual;
> +	if (req->usb_req.length)
> +		dma_sync_single_for_device(udc->dev, src,
> +						length, DMA_TO_DEVICE);
> +	if (!ep->curbufnum && !ep->buffer0ready) {
> +		/* Get the Buffer address and copy the transmit data.*/
> +		eprambase = (u32 __force *)(udc->base_address +
> +				ep->rambase);
> +		dst = virt_to_phys(eprambase);
> +		udc->write_fn(udc->base_address, ep->offset +
> +				XUSB_EP_BUF0COUNT_OFFSET, length);
> +		udc->write_fn(udc->base_address, XUSB_DMA_CONTROL_OFFSET,
> +				XUSB_DMA_BRR_CTRL | (1 << ep->epnumber));
> +		ep->buffer0ready = 1;
> +		ep->curbufnum = 1;
> +	} else if (ep->curbufnum && !ep->buffer1ready) {
> +		/* Get the Buffer address and copy the transmit data.*/
> +		eprambase = (u32 __force *)(udc->base_address +
> +				ep->rambase + ep->ep_usb.maxpacket);
> +		dst = virt_to_phys(eprambase);
> +		udc->write_fn(udc->base_address, ep->offset +
> +				XUSB_EP_BUF1COUNT_OFFSET, length);
> +		udc->write_fn(udc->base_address, XUSB_DMA_CONTROL_OFFSET,
> +				XUSB_DMA_BRR_CTRL | (1 << (ep->epnumber +
> +				XUSB_STATUS_EP_BUFF2_SHIFT)));
> +		ep->buffer1ready = 1;
> +		ep->curbufnum = 0;
> +	} else {
> +		/* None of ping pong buffers are ready currently .*/
> +		return -EAGAIN;
> +	}
> +
> +	ret = xudc_start_dma(ep, src, dst, length);
> +	return ret;

return xudc_start_dma(ep, src, dst, length);

... so you don't need 'ret' at all.

> +static int xudc_dma_receive(struct xusb_ep *ep, struct xusb_req *req,
> +		u8 *buffer, u32 length)
> +{
> +	u32 *eprambase;
> +	dma_addr_t src;
> +	dma_addr_t dst;
> +	int ret = 0;
> +	struct xusb_udc *udc = ep->udc;
> +
> +	dst = req->usb_req.dma + req->usb_req.actual;
> +
> +	if (!ep->curbufnum && !ep->buffer0ready) {
> +		/* Get the Buffer address and copy the transmit data */
> +		eprambase = (u32 __force *)(udc->base_address +
> +				ep->rambase);
> +		src = virt_to_phys(eprambase);
> +		udc->write_fn(udc->base_address, XUSB_DMA_CONTROL_OFFSET,
> +				XUSB_DMA_BRR_CTRL | XUSB_DMA_READ_FROM_DPRAM |
> +				(1 << ep->epnumber));
> +		ep->buffer0ready = 1;
> +		ep->curbufnum = 1;
> +	} else if (ep->curbufnum && !ep->buffer1ready) {
> +		/* Get the Buffer address and copy the transmit data */
> +		eprambase = (u32 __force *)(udc->base_address +
> +				ep->rambase + ep->ep_usb.maxpacket);
> +		src = virt_to_phys(eprambase);
> +		udc->write_fn(udc->base_address, XUSB_DMA_CONTROL_OFFSET,
> +				XUSB_DMA_BRR_CTRL | XUSB_DMA_READ_FROM_DPRAM |
> +				(1 << (ep->epnumber +
> +				XUSB_STATUS_EP_BUFF2_SHIFT)));
> +		ep->buffer1ready = 1;
> +		ep->curbufnum = 0;
> +	} else {
> +		/* None of the ping-pong buffers are ready currently */
> +		return -EAGAIN;
> +	}
> +
> +	ret = xudc_start_dma(ep, src, dst, length);
> +	return ret;

Dito.

> +static int xudc_eptxrx(struct xusb_ep *ep, struct xusb_req *req,
> +		u8 *bufferptr, u32 bufferlen)
> +{
> +	u32 *eprambase;
> +	u32 bytestosend;
> +	u8 *temprambase;
> +	int rc = 0;
> +	struct xusb_udc *udc = ep->udc;
> +
> +	bytestosend = bufferlen;
> +	if (udc->dma_enabled) {
> +		if (ep->is_in)
> +			rc = xudc_dma_send(ep, req, bufferptr, bufferlen);
> +		else
> +			rc = xudc_dma_receive(ep, req, bufferptr, bufferlen);
> +		return rc;
> +	}
> +	/* Put the transmit buffer into the correct ping-pong buffer.*/
> +	if (!ep->curbufnum && !ep->buffer0ready) {
> +		/* Get the Buffer address and copy the transmit data.*/
> +		eprambase = (u32 __force *)(udc->base_address + ep->rambase);
> +		while (bytestosend > 3) {
> +			if (ep->is_in)
> +				*eprambase++ = *(u32 *)bufferptr;
> +			else
> +				*(u32 *)bufferptr = *eprambase++;
> +			bufferptr += 4;
> +			bytestosend -= 4;
> +		}
> +		temprambase = (u8 *)eprambase;
> +		while (bytestosend--) {
> +			if (ep->is_in)
> +				*temprambase++ = *bufferptr++;
> +			else
> +				*bufferptr++ = *temprambase++;
> +		}

Why not use memcpy()?

> +		/*
> +		 * Set the Buffer count register with transmit length
> +		 * and enable the buffer for transmission.
> +		 */
> +		if (ep->is_in)
> +			udc->write_fn(udc->base_address, ep->offset +
> +					XUSB_EP_BUF0COUNT_OFFSET, bufferlen);
> +		udc->write_fn(udc->base_address, XUSB_BUFFREADY_OFFSET,
> +				1 << ep->epnumber);
> +		ep->buffer0ready = 1;
> +		ep->curbufnum = 1;
> +	} else if ((ep->curbufnum == 1) && (!ep->buffer1ready)) {
> +		/* Get the Buffer address and copy the transmit data.*/
> +		eprambase = (u32 __force *)(udc->base_address + ep->rambase +
> +				ep->ep_usb.maxpacket);
> +		while (bytestosend > 3) {
> +			if (ep->is_in)
> +				*eprambase++ = *(u32 *)bufferptr;
> +			else
> +				*(u32 *)bufferptr = *eprambase++;
> +			bufferptr += 4;
> +			bytestosend -= 4;
> +		}
> +		temprambase = (u8 *)eprambase;
> +		while (bytestosend--) {
> +			if (ep->is_in)
> +				*temprambase++ = *bufferptr++;
> +			else
> +				*bufferptr++ = *temprambase++;
> +		}

memcpy()?

> +/**
> + * xudc_read_fifo - Reads the data from the given endpoint buffer.
> + * @ep: pointer to the usb device endpoint structure.
> + * @req: pointer to the usb request structure.
> + *
> + * Return: 0 if request is completed and -EAGAIN if not completed.
> + *
> + * Pulls OUT packet data from the endpoint buffer.
> + */
> +static int xudc_read_fifo(struct xusb_ep *ep, struct xusb_req *req)
> +{
> +	u8 *buf;
> +	u32 is_short, count, bufferspace;
> +	u8 bufoffset;
> +	u8 two_pkts = 0;
> +	int ret;
> +	int retval = -EAGAIN;
> +	struct xusb_udc *udc = ep->udc;
> +
> +	if ((ep->buffer0ready == 1) && (ep->buffer1ready == 1)) {

if (ep->buffer0ready && ep->buffer1ready)

is shorter and easier to read.

> +static int xudc_ep_set_halt(struct usb_ep *_ep, int value)
> +{
> +	struct xusb_ep *ep = to_xusb_ep(_ep);
> +	struct xusb_udc *udc;
> +	unsigned long flags;
> +	u32 epcfgreg;
> +
> +	if (!_ep || (!ep->desc && ep->epnumber)) {
> +		pr_debug("%s: bad ep or descriptor\n", __func__);

dev_dbg()

> +static int __xudc_ep_enable(struct xusb_ep *ep,
> +		const struct usb_endpoint_descriptor *desc)
> +{
> +	struct xusb_udc *udc = ep->udc;
> +	u32 tmp;
> +	u8 eptype = 0;
> +	u32 epcfg;
> +	u32 ier;
> +
> +	ep->is_in = ((desc->bEndpointAddress & USB_DIR_IN) != 0);
> +	/* Bit 3...0:endpoint number */
> +	ep->epnumber = (desc->bEndpointAddress & 0x0f);
> +	ep->desc = desc;
> +	ep->ep_usb.desc = desc;
> +	tmp = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
> +	ep->ep_usb.maxpacket = le16_to_cpu(desc->wMaxPacketSize);
> +
> +	switch (tmp) {
> +	case USB_ENDPOINT_XFER_CONTROL:
> +		dev_dbg(udc->dev, "only one control endpoint\n");
> +		/* NON- ISO */
> +		eptype = 0;
> +		return -EINVAL;
> +	case USB_ENDPOINT_XFER_INT:
> +		/* NON- ISO */
> +		eptype = 0;
> +		if (ep->ep_usb.maxpacket > 64)
> +			goto bogus_max;
> +		break;
> +	case USB_ENDPOINT_XFER_BULK:
> +		/* NON- ISO */
> +		eptype = 0;
> +		switch (ep->ep_usb.maxpacket) {
> +		case 8:
> +		case 16:
> +		case 32:
> +		case 64:
> +		case 512:
> +			goto ok;
> +		}

Nit: With is_power_of_2() and some min/max checks, you wouldn't need a
switch here, and hence the jump label could go away.

> +bogus_max:
> +		dev_dbg(udc->dev, "bogus maxpacket %d\n",
> +			ep->ep_usb.maxpacket);
> +		return -EINVAL;
> +	case USB_ENDPOINT_XFER_ISOC:
> +		/* ISO */
> +		eptype = 1;
> +		ep->is_iso = 1;
> +		break;
> +	}
> +ok:

...

> +static int xudc_ep_enable(struct usb_ep *_ep,
> +		const struct usb_endpoint_descriptor *desc)
> +{
> +	struct xusb_ep *ep;
> +	struct xusb_udc *udc;
> +	unsigned long flags;
> +	int ret;
> +
> +	if (!_ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT) {
> +		pr_debug("%s: bad ep or descriptor\n", __func__);

dev_dbg()

> +static int xudc_ep_disable(struct usb_ep *_ep)
> +{
> +	struct xusb_ep *ep;
> +	unsigned long flags;
> +	u32 epcfg;
> +	struct xusb_udc *udc;
> +
> +	if (!_ep) {
> +		pr_debug("%s: invalid ep\n", __func__);

dev_dbg()

> +static int __xudc_ep0_queue(struct xusb_ep *ep0, struct xusb_req *req)
> +{
> +	struct xusb_udc *udc = ep0->udc;
> +	u32 length;
> +	u8 *corebuf;
> +
> +	if (!udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN) {
> +		dev_dbg(udc->dev, "%s, bogus device state\n",
> +			__func__);
> +		return -EINVAL;
> +	}
> +	if (!list_empty(&ep0->queue)) {
> +		dev_dbg(udc->dev, "%s:ep0 busy\n", __func__);
> +		return -EBUSY;
> +	}
> +
> +	req->usb_req.status = -EINPROGRESS;
> +	req->usb_req.actual = 0;
> +
> +	list_add_tail(&req->queue, &ep0->queue);
> +
> +	if (udc->setup.bRequestType & USB_DIR_IN) {
> +		prefetch(req->usb_req.buf);
> +		length = req->usb_req.length;
> +		corebuf = (void __force *) ((ep0->rambase << 2) +
> +				udc->base_address);
> +		length = req->usb_req.actual = min_t(u32, length,
> +						EP0_MAX_PACKET);
> +		memcpy((void *)corebuf, req->usb_req.buf, length);

No need for the cast.

> +		udc->write_fn(udc->base_address, XUSB_EP_BUF0COUNT_OFFSET,
> +				length);
> +		udc->write_fn(udc->base_address, XUSB_BUFFREADY_OFFSET, 1);
> +	} else {
> +		if (udc->setup.wLength) {
> +			/* Enable EP0 buffer to receive data */
> +			udc->write_fn(udc->base_address,
> +					XUSB_EP_BUF0COUNT_OFFSET, 0);
> +			udc->write_fn(udc->base_address,
> +					XUSB_BUFFREADY_OFFSET, 1);
> +		} else {
> +			xudc_wrstatus(udc);
> +		}
> +	}
> +
> +	return 0;
> +}
> +

...

> +/**
> + * xudc_handle_setup - Processes the setup packet.
> + * @udc: pointer to the usb device controller structure.
> + *
> + * Process setup packet and delegate to gadget layer.
> + */
> +static void xudc_handle_setup(struct xusb_udc *udc)
> +{
> +	struct xusb_ep *ep0 = &udc->ep[0];
> +	struct usb_ctrlrequest setup;
> +	u32 *ep0rambase;
> +
> +	/* Load up the chapter 9 command buffer.*/
> +	ep0rambase = (u32 __force *) (udc->base_address +
> +				  XUSB_SETUP_PKT_ADDR_OFFSET);
> +	memcpy((void *)&setup, (void *)ep0rambase, 8);

Dito.

> +static void xudc_ep0_in(struct xusb_udc *udc)
> +{
> +	struct xusb_ep *ep0 = &udc->ep[0];
> +	struct xusb_req *req;
> +	unsigned int bytes_to_tx;
> +	void *buffer;
> +	u32 epcfgreg;
> +	u16 count = 0;
> +	u16 length;
> +	u8 *ep0rambase;
> +	u8 test_mode = udc->setup.wIndex >> 8;
> +
> +	req = list_first_entry(&ep0->queue, struct xusb_req, queue);
> +	bytes_to_tx = req->usb_req.length - req->usb_req.actual;
> +
> +	switch (udc->setupseqtx) {
> +	case STATUS_PHASE:
> +		switch (udc->setup.bRequest) {
> +		case USB_REQ_SET_ADDRESS:
> +			/* Set the address of the device.*/
> +			udc->write_fn(udc->base_address,
> +					XUSB_ADDRESS_OFFSET,
> +					udc->setup.wValue);
> +			break;
> +		case USB_REQ_SET_FEATURE:
> +			if (udc->setup.bRequestType ==
> +					USB_RECIP_DEVICE) {
> +				if (udc->setup.wValue ==
> +						USB_DEVICE_TEST_MODE)
> +					udc->write_fn(udc->base_address,
> +							XUSB_TESTMODE_OFFSET,
> +							test_mode);
> +			}
> +			break;
> +		}
> +		req->usb_req.actual = req->usb_req.length;
> +		xudc_done(ep0, req, 0);
> +		break;
> +	case DATA_PHASE:
> +		if (!bytes_to_tx) {
> +			/*
> +			 * We're done with data transfer, next
> +			 * will be zero length OUT with data toggle of
> +			 * 1. Setup data_toggle.
> +			 */
> +			epcfgreg = udc->read_fn(udc->base_address +
> +					ep0->offset);
> +			epcfgreg |= XUSB_EP_CFG_DATA_TOGGLE_MASK;
> +			udc->write_fn(udc->base_address, ep0->offset, epcfgreg);
> +			udc->setupseqtx = STATUS_PHASE;
> +		} else {
> +			length = count = min_t(u32, bytes_to_tx,
> +						EP0_MAX_PACKET);
> +			/* Copy the data to be transmitted into the DPRAM. */
> +			ep0rambase = (u8 __force *) (udc->base_address +
> +					(ep0->rambase << 2));
> +
> +			buffer = req->usb_req.buf + req->usb_req.actual;
> +			req->usb_req.actual = req->usb_req.actual + length;
> +			memcpy((void *)ep0rambase, buffer, length);

Dito.

+/**
+ * xudc_eps_init - initialize endpoints.
+ * @udc: pointer to the usb device controller structure.
+ */
+static void xudc_eps_init(struct xusb_udc *udc)
+{
+	u32 ep_number;
+	char name[4];
+
+	INIT_LIST_HEAD(&udc->gadget.ep_list);
+
+	for (ep_number = 0; ep_number < XUSB_MAX_ENDPOINTS; ep_number++) {
+		struct xusb_ep *ep = &udc->ep[ep_number];
+
+		if (ep_number) {
+			list_add_tail(&ep->ep_usb.ep_list,
+					&udc->gadget.ep_list);
+			usb_ep_set_maxpacket_limit(&ep->ep_usb,
+					(unsigned short) ~0);
+			sprintf(name, "ep%d", ep_number);
+			strcpy(ep->name, name);
+			ep->ep_usb.name = ep->name;

Why not use ep->name directly? Also, I'd prefer snprintf() here, even if
you're sure this can't overflow :)

> +static int xudc_probe(struct platform_device *pdev)
> +{
> +	struct device_node *np = pdev->dev.of_node;
> +	struct resource *res;
> +	struct xusb_udc *udc;
> +	struct xusb_ep *ep0;
> +	int irq;
> +	int ret;
> +	u32 ier;
> +	u8 *buff;
> +
> +	udc = devm_kzalloc(&pdev->dev, sizeof(*udc), GFP_KERNEL);
> +	if (!udc)
> +		return -ENOMEM;
> +
> +	/* Map the registers */
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	udc->base_address = devm_ioremap_resource(&pdev->dev, res);
> +	if (!udc->base_address)
> +		return -ENOMEM;
> +
> +	irq = platform_get_irq(pdev, 0);
> +	if (irq < 0) {
> +		dev_err(&pdev->dev, "unable to get irq\n");
> +		return irq;
> +	}
> +	ret = devm_request_irq(&pdev->dev, irq, xudc_irq, 0,
> +				dev_name(&pdev->dev), udc);
> +	if (ret < 0) {
> +		dev_dbg(&pdev->dev, "unable to request irq %d", irq);
> +		goto fail;
> +	}
> +
> +	udc->dma_enabled = of_property_read_bool(np, "xlnx,has-builtin-dma");
> +
> +	/* Setup gadget structure */
> +	udc->gadget.ops = &xusb_udc_ops;
> +	udc->gadget.max_speed = USB_SPEED_HIGH;
> +	udc->gadget.speed = USB_SPEED_UNKNOWN;
> +	udc->gadget.ep0 = &udc->ep[XUSB_EP_NUMBER_ZERO].ep_usb;
> +	udc->gadget.name = driver_name;
> +
> +	spin_lock_init(&udc->lock);
> +
> +	/* Check for IP endianness */
> +	udc->write_fn = xudc_write32_be;
> +	udc->read_fn = xudc_read32_be;
> +	udc->write_fn(udc->base_address, XUSB_TESTMODE_OFFSET, TEST_J);
> +	if ((udc->read_fn(udc->base_address + XUSB_TESTMODE_OFFSET))
> +			!= TEST_J) {
> +		udc->write_fn = xudc_write32;
> +		udc->read_fn = xudc_read32;
> +	}
> +	udc->write_fn(udc->base_address, XUSB_TESTMODE_OFFSET, 0);
> +
> +	xudc_eps_init(udc);
> +
> +	ep0 = &udc->ep[0];
> +	/* Create a dummy request for GET_STATUS, SET_ADDRESS */
> +	udc->req = container_of(xudc_ep_alloc_request(&ep0->ep_usb, GFP_KERNEL),
> +				struct xusb_req, usb_req);
> +	if (!udc->req) {
> +		ret = -ENOMEM;
> +		goto fail;
> +	}
> +
> +	/* buffer for data of get_status request */
> +	buff = kzalloc(2, GFP_KERNEL);
> +	if (buff == NULL) {
> +		ret = -ENOMEM;
> +		goto fail;
> +	}
> +	/* Dummy request ready, free this in remove */
> +	udc->req->usb_req.buf = buff;

devm_kzalloc() solves this for you.

> +static int xudc_remove(struct platform_device *pdev)
> +{
> +	struct xusb_udc *udc = platform_get_drvdata(pdev);
> +	void *buf = udc->req->usb_req.buf;
> +
> +	usb_del_gadget_udc(&udc->gadget);
> +
> +	/* free memory allocated for dummy request buffer */
> +	kfree(buf);
> +	/* free memory allocated for dummy request */
> +	kfree(udc->req);

These comments don't really help anyone - it's pretty obvious what
happens here :) But those will vanish with devm_kzalloc() anyway.



Thanks,
Daniel

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Re: [PATCH v4 2/2] usb: gadget: Add xilinx usb2 device support

[Daniel Mack]

On 08/19/2014 11:56 AM, Daniel Mack wrote:
> On 07/22/2014 11:08 AM, Subbaraya Sundeep Bhatta wrote:

>>  drivers/usb/gadget/Kconfig      |   14 +
>>  drivers/usb/gadget/Makefile     |    1 +
>>  drivers/usb/gadget/udc-xilinx.c | 2261 +++++++++++++++++++++++++++++++++++++++
>>  3 files changed, 2276 insertions(+), 0 deletions(-)
>>  create mode 100644 drivers/usb/gadget/udc-xilinx.c
> 
> As your driver has a DT binding, you have to describe it in
> Documentation/devicetree/bindings.

Ah, sorry. I missed patch 1/2 which does that.


Thanks,
Daniel

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Re: [PATCH v4 2/2] usb: gadget: Add xilinx usb2 device support

[sundeep subbaraya]

Hi Daniel,

On Tue, Aug 19, 2014 at 3:26 PM, Daniel Mack <daniel@zonque.org> wrote:
> Hi,
>
> On 07/22/2014 11:08 AM, Subbaraya Sundeep Bhatta wrote:
>> This patch adds xilinx usb2 device driver support
>
> Add some more information here, please. Copying the text from the
> Kconfig option is already a good start.
>
>>  drivers/usb/gadget/Kconfig      |   14 +
>>  drivers/usb/gadget/Makefile     |    1 +
>>  drivers/usb/gadget/udc-xilinx.c | 2261 +++++++++++++++++++++++++++++++++++++++
>>  3 files changed, 2276 insertions(+), 0 deletions(-)
>>  create mode 100644 drivers/usb/gadget/udc-xilinx.c
>
> As your driver has a DT binding, you have to describe it in
> Documentation/devicetree/bindings.
>
>> --- a/drivers/usb/gadget/Kconfig
>> +++ b/drivers/usb/gadget/Kconfig
>> @@ -459,6 +459,20 @@ config USB_EG20T
>>         ML7213/ML7831 is companion chip for Intel Atom E6xx series.
>>         ML7213/ML7831 is completely compatible for Intel EG20T PCH.
>>
>> +config USB_GADGET_XILINX
>> +     tristate "Xilinx USB Driver"
>> +     depends on COMPILE_TEST
>
> Why would you depend on that?

Felipe asked to make this since this is USB soft IP driver and its
dependencies have tendency to grow.
Currently tested on arm and microblaze architectures.

>
> Also, your code uses device tree functions unconditionally, which is
> fine, but it must hence depend on 'OF'.

Ok will add OF along with COMPILE_TEST

>
>> +struct xusb_ep {
>> +     struct usb_ep ep_usb;
>> +     struct list_head queue;
>> +     struct xusb_udc *udc;
>> +     const struct usb_endpoint_descriptor *desc;
>> +     u32 rambase;
>> +     u32 offset;
>> +     char name[4];
>> +     u16 epnumber;
>> +     u16 maxpacket;
>> +     u16 buffer0count;
>> +     u16 buffer1count;
>> +     u8 buffer0ready;
>> +     u8 buffer1ready;
>> +     u8 eptype;
>> +     u8 curbufnum;
>> +     u8 is_in;
>> +     u8 is_iso;
>
> Some of those could probably become booleans.

Ok

>
>> +struct xusb_udc {
>> +     struct usb_gadget gadget;
>> +     struct xusb_ep ep[8];
>> +     struct usb_gadget_driver *driver;
>> +     struct usb_ctrlrequest setup;
>> +     struct xusb_req *req;
>> +     struct device *dev;
>> +     u32 usb_state;
>> +     u32 remote_wkp;
>> +     u32 setupseqtx;
>> +     u32 setupseqrx;
>> +     void __iomem *base_address;
>> +     spinlock_t lock;
>> +     bool dma_enabled;
>> +
>> +     unsigned int (*read_fn)(void __iomem *);
>> +     void (*write_fn)(void __iomem *, u32, u32);
>> +};
>> +
>> +/* Endpoint buffer start addresses in the core */
>> +static u32 rambase[8] = { 0x22, 0x1000, 0x1100, 0x1200, 0x1300, 0x1400, 0x1500,
>> +                     0x1600 };
>
> As stated by Peter, indenting such lines to match the position of the
> line before makes such code much prettier and more readable. It's also
> done in the majority of drivers.
>
> This counts for many locations in your code.

Ok

>
>> +/* Control endpoint configuration.*/
>> +static const struct usb_endpoint_descriptor config_bulk_out_desc = {
>> +     .bLength                = USB_DT_ENDPOINT_SIZE,
>> +     .bDescriptorType        = USB_DT_ENDPOINT,
>> +     .bEndpointAddress       = USB_DIR_OUT,
>> +     .bmAttributes           = USB_ENDPOINT_XFER_BULK,
>> +     .wMaxPacketSize         = cpu_to_le16(64),
>
> Why not use EP0_MAX_PACKET here?

Ok

>
>> +static void xudc_wrstatus(struct xusb_udc *udc)
>> +{
>> +     struct xusb_ep *ep0 = &udc->ep[XUSB_EP_NUMBER_ZERO];
>> +     u32 epcfgreg;
>> +
>> +     epcfgreg = udc->read_fn(udc->base_address + ep0->offset)|
>> +                     XUSB_EP_CFG_DATA_TOGGLE_MASK;
>> +     udc->write_fn(udc->base_address, ep0->offset, epcfgreg);
>> +     udc->write_fn(udc->base_address, ep0->offset + XUSB_EP_BUF0COUNT_OFFSET,
>> +                     0);
>
> Just a nit, but renaming 'base_address' to something like 'base' or
> 'addr' would help you get around or maximum line constraint here and in
> some other places.

Ok i will do this

>
>> +static int xudc_dma_send(struct xusb_ep *ep, struct xusb_req *req,
>> +             u8 *buffer, u32 length)
>> +{
>> +     u32 *eprambase;
>> +     dma_addr_t src;
>> +     dma_addr_t dst;
>> +     int ret;
>> +     struct xusb_udc *udc = ep->udc;
>> +
>> +     src = req->usb_req.dma + req->usb_req.actual;
>> +     if (req->usb_req.length)
>> +             dma_sync_single_for_device(udc->dev, src,
>> +                                             length, DMA_TO_DEVICE);
>> +     if (!ep->curbufnum && !ep->buffer0ready) {
>> +             /* Get the Buffer address and copy the transmit data.*/
>> +             eprambase = (u32 __force *)(udc->base_address +
>> +                             ep->rambase);
>> +             dst = virt_to_phys(eprambase);
>> +             udc->write_fn(udc->base_address, ep->offset +
>> +                             XUSB_EP_BUF0COUNT_OFFSET, length);
>> +             udc->write_fn(udc->base_address, XUSB_DMA_CONTROL_OFFSET,
>> +                             XUSB_DMA_BRR_CTRL | (1 << ep->epnumber));
>> +             ep->buffer0ready = 1;
>> +             ep->curbufnum = 1;
>> +     } else if (ep->curbufnum && !ep->buffer1ready) {
>> +             /* Get the Buffer address and copy the transmit data.*/
>> +             eprambase = (u32 __force *)(udc->base_address +
>> +                             ep->rambase + ep->ep_usb.maxpacket);
>> +             dst = virt_to_phys(eprambase);
>> +             udc->write_fn(udc->base_address, ep->offset +
>> +                             XUSB_EP_BUF1COUNT_OFFSET, length);
>> +             udc->write_fn(udc->base_address, XUSB_DMA_CONTROL_OFFSET,
>> +                             XUSB_DMA_BRR_CTRL | (1 << (ep->epnumber +
>> +                             XUSB_STATUS_EP_BUFF2_SHIFT)));
>> +             ep->buffer1ready = 1;
>> +             ep->curbufnum = 0;
>> +     } else {
>> +             /* None of ping pong buffers are ready currently .*/
>> +             return -EAGAIN;
>> +     }
>> +
>> +     ret = xudc_start_dma(ep, src, dst, length);
>> +     return ret;
>
> return xudc_start_dma(ep, src, dst, length);
>
> ... so you don't need 'ret' at all.

Ok

>
>> +static int xudc_dma_receive(struct xusb_ep *ep, struct xusb_req *req,
>> +             u8 *buffer, u32 length)
>> +{
>> +     u32 *eprambase;
>> +     dma_addr_t src;
>> +     dma_addr_t dst;
>> +     int ret = 0;
>> +     struct xusb_udc *udc = ep->udc;
>> +
>> +     dst = req->usb_req.dma + req->usb_req.actual;
>> +
>> +     if (!ep->curbufnum && !ep->buffer0ready) {
>> +             /* Get the Buffer address and copy the transmit data */
>> +             eprambase = (u32 __force *)(udc->base_address +
>> +                             ep->rambase);
>> +             src = virt_to_phys(eprambase);
>> +             udc->write_fn(udc->base_address, XUSB_DMA_CONTROL_OFFSET,
>> +                             XUSB_DMA_BRR_CTRL | XUSB_DMA_READ_FROM_DPRAM |
>> +                             (1 << ep->epnumber));
>> +             ep->buffer0ready = 1;
>> +             ep->curbufnum = 1;
>> +     } else if (ep->curbufnum && !ep->buffer1ready) {
>> +             /* Get the Buffer address and copy the transmit data */
>> +             eprambase = (u32 __force *)(udc->base_address +
>> +                             ep->rambase + ep->ep_usb.maxpacket);
>> +             src = virt_to_phys(eprambase);
>> +             udc->write_fn(udc->base_address, XUSB_DMA_CONTROL_OFFSET,
>> +                             XUSB_DMA_BRR_CTRL | XUSB_DMA_READ_FROM_DPRAM |
>> +                             (1 << (ep->epnumber +
>> +                             XUSB_STATUS_EP_BUFF2_SHIFT)));
>> +             ep->buffer1ready = 1;
>> +             ep->curbufnum = 0;
>> +     } else {
>> +             /* None of the ping-pong buffers are ready currently */
>> +             return -EAGAIN;
>> +     }
>> +
>> +     ret = xudc_start_dma(ep, src, dst, length);
>> +     return ret;
>
> Dito.
>
>> +static int xudc_eptxrx(struct xusb_ep *ep, struct xusb_req *req,
>> +             u8 *bufferptr, u32 bufferlen)
>> +{
>> +     u32 *eprambase;
>> +     u32 bytestosend;
>> +     u8 *temprambase;
>> +     int rc = 0;
>> +     struct xusb_udc *udc = ep->udc;
>> +
>> +     bytestosend = bufferlen;
>> +     if (udc->dma_enabled) {
>> +             if (ep->is_in)
>> +                     rc = xudc_dma_send(ep, req, bufferptr, bufferlen);
>> +             else
>> +                     rc = xudc_dma_receive(ep, req, bufferptr, bufferlen);
>> +             return rc;
>> +     }
>> +     /* Put the transmit buffer into the correct ping-pong buffer.*/
>> +     if (!ep->curbufnum && !ep->buffer0ready) {
>> +             /* Get the Buffer address and copy the transmit data.*/
>> +             eprambase = (u32 __force *)(udc->base_address + ep->rambase);
>> +             while (bytestosend > 3) {
>> +                     if (ep->is_in)
>> +                             *eprambase++ = *(u32 *)bufferptr;
>> +                     else
>> +                             *(u32 *)bufferptr = *eprambase++;
>> +                     bufferptr += 4;
>> +                     bytestosend -= 4;
>> +             }
>> +             temprambase = (u8 *)eprambase;
>> +             while (bytestosend--) {
>> +                     if (ep->is_in)
>> +                             *temprambase++ = *bufferptr++;
>> +                     else
>> +                             *bufferptr++ = *temprambase++;
>> +             }
>
> Why not use memcpy()?

Ok

>
>> +             /*
>> +              * Set the Buffer count register with transmit length
>> +              * and enable the buffer for transmission.
>> +              */
>> +             if (ep->is_in)
>> +                     udc->write_fn(udc->base_address, ep->offset +
>> +                                     XUSB_EP_BUF0COUNT_OFFSET, bufferlen);
>> +             udc->write_fn(udc->base_address, XUSB_BUFFREADY_OFFSET,
>> +                             1 << ep->epnumber);
>> +             ep->buffer0ready = 1;
>> +             ep->curbufnum = 1;
>> +     } else if ((ep->curbufnum == 1) && (!ep->buffer1ready)) {
>> +             /* Get the Buffer address and copy the transmit data.*/
>> +             eprambase = (u32 __force *)(udc->base_address + ep->rambase +
>> +                             ep->ep_usb.maxpacket);
>> +             while (bytestosend > 3) {
>> +                     if (ep->is_in)
>> +                             *eprambase++ = *(u32 *)bufferptr;
>> +                     else
>> +                             *(u32 *)bufferptr = *eprambase++;
>> +                     bufferptr += 4;
>> +                     bytestosend -= 4;
>> +             }
>> +             temprambase = (u8 *)eprambase;
>> +             while (bytestosend--) {
>> +                     if (ep->is_in)
>> +                             *temprambase++ = *bufferptr++;
>> +                     else
>> +                             *bufferptr++ = *temprambase++;
>> +             }
>
> memcpy()?

Ok

>
>> +/**
>> + * xudc_read_fifo - Reads the data from the given endpoint buffer.
>> + * @ep: pointer to the usb device endpoint structure.
>> + * @req: pointer to the usb request structure.
>> + *
>> + * Return: 0 if request is completed and -EAGAIN if not completed.
>> + *
>> + * Pulls OUT packet data from the endpoint buffer.
>> + */
>> +static int xudc_read_fifo(struct xusb_ep *ep, struct xusb_req *req)
>> +{
>> +     u8 *buf;
>> +     u32 is_short, count, bufferspace;
>> +     u8 bufoffset;
>> +     u8 two_pkts = 0;
>> +     int ret;
>> +     int retval = -EAGAIN;
>> +     struct xusb_udc *udc = ep->udc;
>> +
>> +     if ((ep->buffer0ready == 1) && (ep->buffer1ready == 1)) {
>
> if (ep->buffer0ready && ep->buffer1ready)
>
> is shorter and easier to read.

Ok

>
>> +static int xudc_ep_set_halt(struct usb_ep *_ep, int value)
>> +{
>> +     struct xusb_ep *ep = to_xusb_ep(_ep);
>> +     struct xusb_udc *udc;
>> +     unsigned long flags;
>> +     u32 epcfgreg;
>> +
>> +     if (!_ep || (!ep->desc && ep->epnumber)) {
>> +             pr_debug("%s: bad ep or descriptor\n", __func__);
>
> dev_dbg()

device structure is in ep so first checking for proper ep and later use dev_dbg.

>
>> +static int __xudc_ep_enable(struct xusb_ep *ep,
>> +             const struct usb_endpoint_descriptor *desc)
>> +{
>> +     struct xusb_udc *udc = ep->udc;
>> +     u32 tmp;
>> +     u8 eptype = 0;
>> +     u32 epcfg;
>> +     u32 ier;
>> +
>> +     ep->is_in = ((desc->bEndpointAddress & USB_DIR_IN) != 0);
>> +     /* Bit 3...0:endpoint number */
>> +     ep->epnumber = (desc->bEndpointAddress & 0x0f);
>> +     ep->desc = desc;
>> +     ep->ep_usb.desc = desc;
>> +     tmp = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
>> +     ep->ep_usb.maxpacket = le16_to_cpu(desc->wMaxPacketSize);
>> +
>> +     switch (tmp) {
>> +     case USB_ENDPOINT_XFER_CONTROL:
>> +             dev_dbg(udc->dev, "only one control endpoint\n");
>> +             /* NON- ISO */
>> +             eptype = 0;
>> +             return -EINVAL;
>> +     case USB_ENDPOINT_XFER_INT:
>> +             /* NON- ISO */
>> +             eptype = 0;
>> +             if (ep->ep_usb.maxpacket > 64)
>> +                     goto bogus_max;
>> +             break;
>> +     case USB_ENDPOINT_XFER_BULK:
>> +             /* NON- ISO */
>> +             eptype = 0;
>> +             switch (ep->ep_usb.maxpacket) {
>> +             case 8:
>> +             case 16:
>> +             case 32:
>> +             case 64:
>> +             case 512:
>> +                     goto ok;
>> +             }
>
> Nit: With is_power_of_2() and some min/max checks, you wouldn't need a
> switch here, and hence the jump label could go away.

Ok

>
>> +bogus_max:
>> +             dev_dbg(udc->dev, "bogus maxpacket %d\n",
>> +                     ep->ep_usb.maxpacket);
>> +             return -EINVAL;
>> +     case USB_ENDPOINT_XFER_ISOC:
>> +             /* ISO */
>> +             eptype = 1;
>> +             ep->is_iso = 1;
>> +             break;
>> +     }
>> +ok:
>
> ...
>
>> +static int xudc_ep_enable(struct usb_ep *_ep,
>> +             const struct usb_endpoint_descriptor *desc)
>> +{
>> +     struct xusb_ep *ep;
>> +     struct xusb_udc *udc;
>> +     unsigned long flags;
>> +     int ret;
>> +
>> +     if (!_ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT) {
>> +             pr_debug("%s: bad ep or descriptor\n", __func__);
>
> dev_dbg()

device structure is in ep so first checking for proper ep and later use dev_dbg.

>
>> +static int xudc_ep_disable(struct usb_ep *_ep)
>> +{
>> +     struct xusb_ep *ep;
>> +     unsigned long flags;
>> +     u32 epcfg;
>> +     struct xusb_udc *udc;
>> +
>> +     if (!_ep) {
>> +             pr_debug("%s: invalid ep\n", __func__);
>
> dev_dbg()

device structure is in ep so first checking for proper ep and later use dev_dbg.

>
>> +static int __xudc_ep0_queue(struct xusb_ep *ep0, struct xusb_req *req)
>> +{
>> +     struct xusb_udc *udc = ep0->udc;
>> +     u32 length;
>> +     u8 *corebuf;
>> +
>> +     if (!udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN) {
>> +             dev_dbg(udc->dev, "%s, bogus device state\n",
>> +                     __func__);
>> +             return -EINVAL;
>> +     }
>> +     if (!list_empty(&ep0->queue)) {
>> +             dev_dbg(udc->dev, "%s:ep0 busy\n", __func__);
>> +             return -EBUSY;
>> +     }
>> +
>> +     req->usb_req.status = -EINPROGRESS;
>> +     req->usb_req.actual = 0;
>> +
>> +     list_add_tail(&req->queue, &ep0->queue);
>> +
>> +     if (udc->setup.bRequestType & USB_DIR_IN) {
>> +             prefetch(req->usb_req.buf);
>> +             length = req->usb_req.length;
>> +             corebuf = (void __force *) ((ep0->rambase << 2) +
>> +                             udc->base_address);
>> +             length = req->usb_req.actual = min_t(u32, length,
>> +                                             EP0_MAX_PACKET);
>> +             memcpy((void *)corebuf, req->usb_req.buf, length);
>
> No need for the cast.

Ok

>
>> +             udc->write_fn(udc->base_address, XUSB_EP_BUF0COUNT_OFFSET,
>> +                             length);
>> +             udc->write_fn(udc->base_address, XUSB_BUFFREADY_OFFSET, 1);
>> +     } else {
>> +             if (udc->setup.wLength) {
>> +                     /* Enable EP0 buffer to receive data */
>> +                     udc->write_fn(udc->base_address,
>> +                                     XUSB_EP_BUF0COUNT_OFFSET, 0);
>> +                     udc->write_fn(udc->base_address,
>> +                                     XUSB_BUFFREADY_OFFSET, 1);
>> +             } else {
>> +                     xudc_wrstatus(udc);
>> +             }
>> +     }
>> +
>> +     return 0;
>> +}
>> +
>
> ...
>
>> +/**
>> + * xudc_handle_setup - Processes the setup packet.
>> + * @udc: pointer to the usb device controller structure.
>> + *
>> + * Process setup packet and delegate to gadget layer.
>> + */
>> +static void xudc_handle_setup(struct xusb_udc *udc)
>> +{
>> +     struct xusb_ep *ep0 = &udc->ep[0];
>> +     struct usb_ctrlrequest setup;
>> +     u32 *ep0rambase;
>> +
>> +     /* Load up the chapter 9 command buffer.*/
>> +     ep0rambase = (u32 __force *) (udc->base_address +
>> +                               XUSB_SETUP_PKT_ADDR_OFFSET);
>> +     memcpy((void *)&setup, (void *)ep0rambase, 8);
>
> Dito.

Ok

>
>> +static void xudc_ep0_in(struct xusb_udc *udc)
>> +{
>> +     struct xusb_ep *ep0 = &udc->ep[0];
>> +     struct xusb_req *req;
>> +     unsigned int bytes_to_tx;
>> +     void *buffer;
>> +     u32 epcfgreg;
>> +     u16 count = 0;
>> +     u16 length;
>> +     u8 *ep0rambase;
>> +     u8 test_mode = udc->setup.wIndex >> 8;
>> +
>> +     req = list_first_entry(&ep0->queue, struct xusb_req, queue);
>> +     bytes_to_tx = req->usb_req.length - req->usb_req.actual;
>> +
>> +     switch (udc->setupseqtx) {
>> +     case STATUS_PHASE:
>> +             switch (udc->setup.bRequest) {
>> +             case USB_REQ_SET_ADDRESS:
>> +                     /* Set the address of the device.*/
>> +                     udc->write_fn(udc->base_address,
>> +                                     XUSB_ADDRESS_OFFSET,
>> +                                     udc->setup.wValue);
>> +                     break;
>> +             case USB_REQ_SET_FEATURE:
>> +                     if (udc->setup.bRequestType ==
>> +                                     USB_RECIP_DEVICE) {
>> +                             if (udc->setup.wValue ==
>> +                                             USB_DEVICE_TEST_MODE)
>> +                                     udc->write_fn(udc->base_address,
>> +                                                     XUSB_TESTMODE_OFFSET,
>> +                                                     test_mode);
>> +                     }
>> +                     break;
>> +             }
>> +             req->usb_req.actual = req->usb_req.length;
>> +             xudc_done(ep0, req, 0);
>> +             break;
>> +     case DATA_PHASE:
>> +             if (!bytes_to_tx) {
>> +                     /*
>> +                      * We're done with data transfer, next
>> +                      * will be zero length OUT with data toggle of
>> +                      * 1. Setup data_toggle.
>> +                      */
>> +                     epcfgreg = udc->read_fn(udc->base_address +
>> +                                     ep0->offset);
>> +                     epcfgreg |= XUSB_EP_CFG_DATA_TOGGLE_MASK;
>> +                     udc->write_fn(udc->base_address, ep0->offset, epcfgreg);
>> +                     udc->setupseqtx = STATUS_PHASE;
>> +             } else {
>> +                     length = count = min_t(u32, bytes_to_tx,
>> +                                             EP0_MAX_PACKET);
>> +                     /* Copy the data to be transmitted into the DPRAM. */
>> +                     ep0rambase = (u8 __force *) (udc->base_address +
>> +                                     (ep0->rambase << 2));
>> +
>> +                     buffer = req->usb_req.buf + req->usb_req.actual;
>> +                     req->usb_req.actual = req->usb_req.actual + length;
>> +                     memcpy((void *)ep0rambase, buffer, length);
>
> Dito.

Ok

>
> +/**
> + * xudc_eps_init - initialize endpoints.
> + * @udc: pointer to the usb device controller structure.
> + */
> +static void xudc_eps_init(struct xusb_udc *udc)
> +{
> +       u32 ep_number;
> +       char name[4];
> +
> +       INIT_LIST_HEAD(&udc->gadget.ep_list);
> +
> +       for (ep_number = 0; ep_number < XUSB_MAX_ENDPOINTS; ep_number++) {
> +               struct xusb_ep *ep = &udc->ep[ep_number];
> +
> +               if (ep_number) {
> +                       list_add_tail(&ep->ep_usb.ep_list,
> +                                       &udc->gadget.ep_list);
> +                       usb_ep_set_maxpacket_limit(&ep->ep_usb,
> +                                       (unsigned short) ~0);
> +                       sprintf(name, "ep%d", ep_number);
> +                       strcpy(ep->name, name);
> +                       ep->ep_usb.name = ep->name;
>
> Why not use ep->name directly? Also, I'd prefer snprintf() here, even if
> you're sure this can't overflow :)

Ok

>
>> +static int xudc_probe(struct platform_device *pdev)
>> +{
>> +     struct device_node *np = pdev->dev.of_node;
>> +     struct resource *res;
>> +     struct xusb_udc *udc;
>> +     struct xusb_ep *ep0;
>> +     int irq;
>> +     int ret;
>> +     u32 ier;
>> +     u8 *buff;
>> +
>> +     udc = devm_kzalloc(&pdev->dev, sizeof(*udc), GFP_KERNEL);
>> +     if (!udc)
>> +             return -ENOMEM;
>> +
>> +     /* Map the registers */
>> +     res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> +     udc->base_address = devm_ioremap_resource(&pdev->dev, res);
>> +     if (!udc->base_address)
>> +             return -ENOMEM;
>> +
>> +     irq = platform_get_irq(pdev, 0);
>> +     if (irq < 0) {
>> +             dev_err(&pdev->dev, "unable to get irq\n");
>> +             return irq;
>> +     }
>> +     ret = devm_request_irq(&pdev->dev, irq, xudc_irq, 0,
>> +                             dev_name(&pdev->dev), udc);
>> +     if (ret < 0) {
>> +             dev_dbg(&pdev->dev, "unable to request irq %d", irq);
>> +             goto fail;
>> +     }
>> +
>> +     udc->dma_enabled = of_property_read_bool(np, "xlnx,has-builtin-dma");
>> +
>> +     /* Setup gadget structure */
>> +     udc->gadget.ops = &xusb_udc_ops;
>> +     udc->gadget.max_speed = USB_SPEED_HIGH;
>> +     udc->gadget.speed = USB_SPEED_UNKNOWN;
>> +     udc->gadget.ep0 = &udc->ep[XUSB_EP_NUMBER_ZERO].ep_usb;
>> +     udc->gadget.name = driver_name;
>> +
>> +     spin_lock_init(&udc->lock);
>> +
>> +     /* Check for IP endianness */
>> +     udc->write_fn = xudc_write32_be;
>> +     udc->read_fn = xudc_read32_be;
>> +     udc->write_fn(udc->base_address, XUSB_TESTMODE_OFFSET, TEST_J);
>> +     if ((udc->read_fn(udc->base_address + XUSB_TESTMODE_OFFSET))
>> +                     != TEST_J) {
>> +             udc->write_fn = xudc_write32;
>> +             udc->read_fn = xudc_read32;
>> +     }
>> +     udc->write_fn(udc->base_address, XUSB_TESTMODE_OFFSET, 0);
>> +
>> +     xudc_eps_init(udc);
>> +
>> +     ep0 = &udc->ep[0];
>> +     /* Create a dummy request for GET_STATUS, SET_ADDRESS */
>> +     udc->req = container_of(xudc_ep_alloc_request(&ep0->ep_usb, GFP_KERNEL),
>> +                             struct xusb_req, usb_req);
>> +     if (!udc->req) {
>> +             ret = -ENOMEM;
>> +             goto fail;
>> +     }
>> +
>> +     /* buffer for data of get_status request */
>> +     buff = kzalloc(2, GFP_KERNEL);
>> +     if (buff == NULL) {
>> +             ret = -ENOMEM;
>> +             goto fail;
>> +     }
>> +     /* Dummy request ready, free this in remove */
>> +     udc->req->usb_req.buf = buff;
>
> devm_kzalloc() solves this for you.

Ok

>
>> +static int xudc_remove(struct platform_device *pdev)
>> +{
>> +     struct xusb_udc *udc = platform_get_drvdata(pdev);
>> +     void *buf = udc->req->usb_req.buf;
>> +
>> +     usb_del_gadget_udc(&udc->gadget);
>> +
>> +     /* free memory allocated for dummy request buffer */
>> +     kfree(buf);
>> +     /* free memory allocated for dummy request */
>> +     kfree(udc->req);
>
> These comments don't really help anyone - it's pretty obvious what
> happens here :) But those will vanish with devm_kzalloc() anyway.

ok will use devm_kzalloc :)

Thank you,
Sundeep.B.S.

>
>
>
> Thanks,
> Daniel
>
> --
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> More majordomo info at  http://vger.kernel.org/majordomo-info.html
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Re: [PATCH v4 2/2] usb: gadget: Add xilinx usb2 device support

[Felipe Balbi]

[-- Attachment #1: Type: text/plain, Size: 1940 bytes --]

On Thu, Aug 21, 2014 at 12:19:03PM +0530, sundeep subbaraya wrote:
> Hi Daniel,
> 
> On Tue, Aug 19, 2014 at 3:26 PM, Daniel Mack <daniel-cYrQPVfZoowdnm+yROfE0A@public.gmane.org> wrote:
> > Hi,
> >
> > On 07/22/2014 11:08 AM, Subbaraya Sundeep Bhatta wrote:
> >> This patch adds xilinx usb2 device driver support
> >
> > Add some more information here, please. Copying the text from the
> > Kconfig option is already a good start.
> >
> >>  drivers/usb/gadget/Kconfig      |   14 +
> >>  drivers/usb/gadget/Makefile     |    1 +
> >>  drivers/usb/gadget/udc-xilinx.c | 2261 +++++++++++++++++++++++++++++++++++++++
> >>  3 files changed, 2276 insertions(+), 0 deletions(-)
> >>  create mode 100644 drivers/usb/gadget/udc-xilinx.c
> >
> > As your driver has a DT binding, you have to describe it in
> > Documentation/devicetree/bindings.
> >
> >> --- a/drivers/usb/gadget/Kconfig
> >> +++ b/drivers/usb/gadget/Kconfig
> >> @@ -459,6 +459,20 @@ config USB_EG20T
> >>         ML7213/ML7831 is companion chip for Intel Atom E6xx series.
> >>         ML7213/ML7831 is completely compatible for Intel EG20T PCH.
> >>
> >> +config USB_GADGET_XILINX
> >> +     tristate "Xilinx USB Driver"
> >> +     depends on COMPILE_TEST
> >
> > Why would you depend on that?
> 
> Felipe asked to make this since this is USB soft IP driver and its
> dependencies have tendency to grow.

that's not exactly what I asked :-) Usually you only add COMPILE_TEST
when you have an ARCH dependency. So something like:

	depends on ARCH_ARM || COMPILE_TEST

would make it clear that this driver is only available on ARM, but when
doing my build tests, I'd still be able to compile it on x86.

> > Also, your code uses device tree functions unconditionally, which is
> > fine, but it must hence depend on 'OF'.
> 
> Ok will add OF along with COMPILE_TEST

so this would be:

	depends on OF || COMPILE_TEST

-- 
balbi

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 819 bytes --]

Re: [PATCH v4 2/2] usb: gadget: Add xilinx usb2 device support

[sundeep subbaraya]

Hi Felipe,

On Thu, Aug 21, 2014 at 7:30 PM, Felipe Balbi <balbi-l0cyMroinI0@public.gmane.org> wrote:
> On Thu, Aug 21, 2014 at 12:19:03PM +0530, sundeep subbaraya wrote:
>> Hi Daniel,
>>
>> On Tue, Aug 19, 2014 at 3:26 PM, Daniel Mack <daniel-cYrQPVfZoowdnm+yROfE0A@public.gmane.org> wrote:
>> > Hi,
>> >
>> > On 07/22/2014 11:08 AM, Subbaraya Sundeep Bhatta wrote:
>> >> This patch adds xilinx usb2 device driver support
>> >
>> > Add some more information here, please. Copying the text from the
>> > Kconfig option is already a good start.
>> >
>> >>  drivers/usb/gadget/Kconfig      |   14 +
>> >>  drivers/usb/gadget/Makefile     |    1 +
>> >>  drivers/usb/gadget/udc-xilinx.c | 2261 +++++++++++++++++++++++++++++++++++++++
>> >>  3 files changed, 2276 insertions(+), 0 deletions(-)
>> >>  create mode 100644 drivers/usb/gadget/udc-xilinx.c
>> >
>> > As your driver has a DT binding, you have to describe it in
>> > Documentation/devicetree/bindings.
>> >
>> >> --- a/drivers/usb/gadget/Kconfig
>> >> +++ b/drivers/usb/gadget/Kconfig
>> >> @@ -459,6 +459,20 @@ config USB_EG20T
>> >>         ML7213/ML7831 is companion chip for Intel Atom E6xx series.
>> >>         ML7213/ML7831 is completely compatible for Intel EG20T PCH.
>> >>
>> >> +config USB_GADGET_XILINX
>> >> +     tristate "Xilinx USB Driver"
>> >> +     depends on COMPILE_TEST
>> >
>> > Why would you depend on that?
>>
>> Felipe asked to make this since this is USB soft IP driver and its
>> dependencies have tendency to grow.
>
> that's not exactly what I asked :-) Usually you only add COMPILE_TEST
> when you have an ARCH dependency. So something like:
>
>         depends on ARCH_ARM || COMPILE_TEST
>
> would make it clear that this driver is only available on ARM, but when
> doing my build tests, I'd still be able to compile it on x86.

Ok got it :)
>
>> > Also, your code uses device tree functions unconditionally, which is
>> > fine, but it must hence depend on 'OF'.
>>
>> Ok will add OF along with COMPILE_TEST
>
> so this would be:
>
>         depends on OF || COMPILE_TEST
Ok

Thanks,
Sundeep

>
> --
> balbi
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Re: [PATCH v4 2/2] usb: gadget: Add xilinx usb2 device support

[Arnd Bergmann]

On Wednesday 10 September 2014 19:25:11 sundeep subbaraya wrote:
> > that's not exactly what I asked  Usually you only add COMPILE_TEST
> > when you have an ARCH dependency. So something like:
> >
> >         depends on ARCH_ARM || COMPILE_TEST
> >
> > would make it clear that this driver is only available on ARM, but when
> > doing my build tests, I'd still be able to compile it on x86.
> 
> Ok got it 

Most of the xilinx stuff also applies to MICROBLAZE however, so it
may need to be

	ARM || MICROBLAZE || COMPILE_TEST

(not ARCH_ARM, btw).

> >> > Also, your code uses device tree functions unconditionally, which is
> >> > fine, but it must hence depend on 'OF'.
> >>
> >> Ok will add OF along with COMPILE_TEST
> >
> > so this would be:
> >
> >         depends on OF || COMPILE_TEST

If it requires OF to build, you can use 'OF && (ARM || COMPILE_TEST)',
but if there is no compile-time dependency, you can just leave out
the 'depends on OF' completely. You can't even build a Zynq machine
without OF enabled.

	Arnd