[PATCH v4 1/4] usb: cdns2: Device side header file for CDNS2 driver

[Pawel Laszczak]

Patch defines macros, registers and structures used by
Device side driver.

Signed-off-by: Pawel Laszczak <pawell@xxxxxxxxxxx>
---
 drivers/usb/gadget/udc/cdns2/cdns2-gadget.h | 707 ++++++++++++++++++++
 1 file changed, 707 insertions(+)
 create mode 100644 drivers/usb/gadget/udc/cdns2/cdns2-gadget.h

diff --git a/drivers/usb/gadget/udc/cdns2/cdns2-gadget.h b/drivers/usb/gadget/udc/cdns2/cdns2-gadget.h
new file mode 100644
index 000000000000..71e2f62d653a
--- /dev/null
+++ b/drivers/usb/gadget/udc/cdns2/cdns2-gadget.h
@@ -0,0 +1,707 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * USBHS-DEV device controller driver header file
+ *
+ * Copyright (C) 2023 Cadence.
+ *
+ * Author: Pawel Laszczak <pawell@xxxxxxxxxxx>
+ */
+
+#ifndef __LINUX_CDNS2_GADGET
+#define __LINUX_CDNS2_GADGET
+
+#include <linux/usb/gadget.h>
+#include <linux/dma-direction.h>
+
+/*
+ * USBHS register interface.
+ * This corresponds to the USBHS Device Controller Interface.
+ */
+
+/**
+ * struct cdns2_ep0_regs - endpoint 0 related registers.
+ * @rxbc: receive (OUT) 0 endpoint byte count register.
+ * @txbc: transmit (IN) 0 endpoint byte count register.
+ * @cs: 0 endpoint control and status register.
+ * @reserved1: reserved.
+ * @fifo: 0 endpoint fifo register.
+ * @reserved2: reserved.
+ * @setupdat: SETUP data register.
+ * @reserved4: reserved.
+ * @maxpack: 0 endpoint max packet size.
+ */
+struct cdns2_ep0_regs {
+	__u8 rxbc;
+	__u8 txbc;
+	__u8 cs;
+	__u8 reserved1[4];
+	__u8 fifo;
+	__le32 reserved2[94];
+	__u8 setupdat[8];
+	__u8 reserved4[88];
+	__u8 maxpack;
+} __packed __aligned(4);
+
+/* EP0CS - bitmasks. */
+/* Endpoint 0 stall bit for status stage. */
+#define EP0CS_STALL	BIT(0)
+/* HSNAK bit. */
+#define EP0CS_HSNAK	BIT(1)
+/* IN 0 endpoint busy bit. */
+#define EP0CS_TXBSY_MSK	BIT(2)
+/* OUT 0 endpoint busy bit. */
+#define EP0CS_RXBSY_MSK	BIT(3)
+/* Send STALL in the data stage phase. */
+#define EP0CS_DSTALL	BIT(4)
+/* SETUP buffer content was changed. */
+#define EP0CS_CHGSET	BIT(7)
+
+/* EP0FIFO - bitmasks. */
+/* Direction. */
+#define EP0_FIFO_IO_TX	BIT(4)
+/* FIFO auto bit. */
+#define EP0_FIFO_AUTO	BIT(5)
+/* FIFO commit bit. */
+#define EP0_FIFO_COMMIT	BIT(6)
+/* FIFO access bit. */
+#define EP0_FIFO_ACCES	BIT(7)
+
+/**
+ * struct cdns2_epx_base - base endpoint registers.
+ * @rxbc: OUT endpoint byte count register.
+ * @rxcon: OUT endpoint control register.
+ * @rxcs: OUT endpoint control and status register.
+ * @txbc: IN endpoint byte count register.
+ * @txcon: IN endpoint control register.
+ * @txcs: IN endpoint control and status register.
+ */
+struct cdns2_epx_base {
+	__le16 rxbc;
+	__u8 rxcon;
+	__u8 rxcs;
+	__le16 txbc;
+	__u8 txcon;
+	__u8 txcs;
+} __packed __aligned(4);
+
+/* rxcon/txcon - endpoint control register bitmasks. */
+/* Endpoint buffering: 0 - single buffering ... 3 - quad buffering. */
+#define EPX_CON_BUF		GENMASK(1, 0)
+/* Endpoint type. */
+#define EPX_CON_TYPE		GENMASK(3, 2)
+/* Endpoint type: isochronous. */
+#define EPX_CON_TYPE_ISOC	0x4
+/* Endpoint type: bulk. */
+#define EPX_CON_TYPE_BULK	0x8
+/* Endpoint type: interrupt. */
+#define EPX_CON_TYPE_INT	0xC
+/* Number of packets per microframe. */
+#define EPX_CON_ISOD		GENMASK(5, 4)
+#define EPX_CON_ISOD_SHIFT	0x4
+/* Endpoint stall bit. */
+#define EPX_CON_STALL		BIT(6)
+/* Endpoint enable bit.*/
+#define EPX_CON_VAL		BIT(7)
+
+/* rxcs/txcs - endpoint control and status bitmasks. */
+/* Data sequence error for the ISO endpoint. */
+#define EPX_CS_ERR(p)		((p) & BIT(0))
+
+/**
+ * struct cdns2_epx_regs - endpoint 1..15 related registers.
+ * @reserved: reserved.
+ * @ep: none control endpoints array.
+ * @reserved2: reserved.
+ * @endprst: endpoint reset register.
+ * @reserved3: reserved.
+ * @isoautoarm: ISO auto-arm register.
+ * @reserved4: reserved.
+ * @isodctrl: ISO control register.
+ * @reserved5: reserved.
+ * @isoautodump: ISO auto dump enable register.
+ * @reserved6: reserved.
+ * @rxmaxpack: receive (OUT) Max packet size register.
+ * @reserved7: reserved.
+ * @rxstaddr: receive (OUT) start address endpoint buffer register.
+ * @reserved8: reserved.
+ * @txstaddr: transmit (IN) start address endpoint buffer register.
+ * @reserved9: reserved.
+ * @txmaxpack: transmit (IN) Max packet size register.
+ */
+struct cdns2_epx_regs {
+	__le32 reserved[2];
+	struct cdns2_epx_base ep[15];
+	__u8 reserved2[290];
+	__u8 endprst;
+	__u8 reserved3[41];
+	__le16 isoautoarm;
+	__u8 reserved4[10];
+	__le16 isodctrl;
+	__le16 reserved5;
+	__le16 isoautodump;
+	__le32 reserved6;
+	__le16 rxmaxpack[15];
+	__le32 reserved7[65];
+	__le32 rxstaddr[15];
+	__u8 reserved8[4];
+	__le32 txstaddr[15];
+	__u8 reserved9[98];
+	__le16 txmaxpack[15];
+} __packed __aligned(4);
+
+/* ENDPRST - bitmasks. */
+/* Endpoint number. */
+#define ENDPRST_EP	GENMASK(3, 0)
+/* IN direction bit. */
+#define ENDPRST_IO_TX	BIT(4)
+/* Toggle reset bit. */
+#define ENDPRST_TOGRST	BIT(5)
+/* FIFO reset bit. */
+#define ENDPRST_FIFORST	BIT(6)
+/* Toggle status and reset bit. */
+#define ENDPRST_TOGSETQ	BIT(7)
+
+/**
+ * struct cdns2_interrupt_regs - USB interrupt related registers.
+ * @reserved: reserved.
+ * @usbirq: USB interrupt request register.
+ * @extirq: external interrupt request register.
+ * @rxpngirq: external interrupt request register.
+ * @reserved1: reserved.
+ * @usbien: USB interrupt enable register.
+ * @extien: external interrupt enable register.
+ * @reserved2: reserved.
+ * @usbivect: USB interrupt vector register.
+ */
+struct cdns2_interrupt_regs {
+	__u8 reserved[396];
+	__u8 usbirq;
+	__u8 extirq;
+	__le16 rxpngirq;
+	__le16 reserved1[4];
+	__u8 usbien;
+	__u8 extien;
+	__le16 reserved2[3];
+	__u8 usbivect;
+} __packed __aligned(4);
+
+/* EXTIRQ and EXTIEN - bitmasks. */
+/* VBUS fault fall interrupt. */
+#define EXTIRQ_VBUSFAULT_FALL BIT(0)
+/* VBUS fault fall interrupt. */
+#define EXTIRQ_VBUSFAULT_RISE BIT(1)
+/* Wake up interrupt bit. */
+#define EXTIRQ_WAKEUP	BIT(7)
+
+/* USBIEN and USBIRQ - bitmasks. */
+/* SETUP data valid interrupt bit.*/
+#define USBIRQ_SUDAV	BIT(0)
+/* Start-of-frame interrupt bit. */
+#define USBIRQ_SOF	BIT(1)
+/* SETUP token interrupt bit. */
+#define USBIRQ_SUTOK	BIT(2)
+/* USB suspend interrupt bit. */
+#define USBIRQ_SUSPEND	BIT(3)
+/* USB reset interrupt bit. */
+#define USBIRQ_URESET	BIT(4)
+/* USB high-speed mode interrupt bit. */
+#define USBIRQ_HSPEED	BIT(5)
+/* Link Power Management interrupt bit. */
+#define USBIRQ_LPM	BIT(7)
+
+#define USB_IEN_INIT (USBIRQ_SUDAV | USBIRQ_SUSPEND | USBIRQ_URESET \
+		      | USBIRQ_HSPEED | USBIRQ_LPM)
+/**
+ * struct cdns2_usb_regs - USB controller registers.
+ * @reserved: reserved.
+ * @lpmctrl: LPM control register.
+ * @lpmclock: LPM clock register.
+ * @reserved2: reserved.
+ * @endprst: endpoint reset register.
+ * @usbcs: USB control and status register.
+ * @frmnr: USB frame counter register.
+ * @fnaddr: function Address register.
+ * @clkgate: clock gate register.
+ * @fifoctrl: FIFO control register.
+ * @speedctrl: speed Control register.
+ * @sleep_clkgate: sleep Clock Gate register.
+ * @reserved3: reserved.
+ * @cpuctrl: microprocessor control register.
+ */
+struct cdns2_usb_regs {
+	__u8 reserved[4];
+	__u16 lpmctrl;
+	__u8 lpmclock;
+	__u8 reserved2[411];
+	__u8 endprst;
+	__u8 usbcs;
+	__le16 frmnr;
+	__u8 fnaddr;
+	__u8 clkgate;
+	__u8 fifoctrl;
+	__u8 speedctrl;
+	__u8 sleep_clkgate;
+	__u8 reserved3[533];
+	__u8 cpuctrl;
+} __packed __aligned(4);
+
+/* LPMCTRL - bitmasks. */
+/* BESL (Best Effort Service Latency). */
+#define LPMCTRLLL_HIRD		GENMASK(7, 4)
+/* Last received Remote Wakeup field from LPM Extended Token packet. */
+#define LPMCTRLLH_BREMOTEWAKEUP	BIT(8)
+/* Reflects value of the lpmnyet bit located in the usbcs[1] register. */
+#define LPMCTRLLH_LPMNYET	BIT(16)
+
+/* LPMCLOCK - bitmasks. */
+/*
+ * If bit is 1 the controller automatically turns off clock
+ * (utmisleepm goes to low), else the microprocessor should use
+ * sleep clock gate register to turn off clock.
+ */
+#define LPMCLOCK_SLEEP_ENTRY	BIT(7)
+
+/* USBCS - bitmasks. */
+/* Send NYET handshake for the LPM transaction. */
+#define USBCS_LPMNYET		BIT(2)
+/* Remote wake-up bit. */
+#define USBCS_SIGRSUME		BIT(5)
+/* Software disconnect bit. */
+#define USBCS_DISCON		BIT(6)
+/* Indicates that a wakeup pin resumed the controller. */
+#define USBCS_WAKESRC		BIT(7)
+
+/* FIFOCTRL - bitmasks. */
+/* Endpoint number. */
+#define FIFOCTRL_EP		GENMASK(3, 0)
+/* Direction bit. */
+#define FIFOCTRL_IO_TX		BIT(4)
+/* FIFO auto bit. */
+#define FIFOCTRL_FIFOAUTO	BIT(5)
+/* FIFO commit bit. */
+#define FIFOCTRL_FIFOCMIT	BIT(6)
+/* FIFO access bit. */
+#define FIFOCTRL_FIFOACC	BIT(7)
+
+/* SPEEDCTRL - bitmasks. */
+/* Device works in Full Speed. */
+#define SPEEDCTRL_FS		BIT(1)
+/* Device works in High Speed. */
+#define SPEEDCTRL_HS		BIT(2)
+/* Force FS mode. */
+#define SPEEDCTRL_HSDISABLE	BIT(7)
+
+/* CPUCTRL- bitmasks. */
+/* Controller reset bit. */
+#define CPUCTRL_SW_RST		BIT(1)
+
+/**
+ * struct cdns2_adma_regs - ADMA controller registers.
+ * @conf: DMA global configuration register.
+ * @sts: DMA global Status register.
+ * @reserved1: reserved.
+ * @ep_sel: DMA endpoint select register.
+ * @ep_traddr: DMA endpoint transfer ring address register.
+ * @ep_cfg: DMA endpoint configuration register.
+ * @ep_cmd: DMA endpoint command register.
+ * @ep_sts: DMA endpoint status register.
+ * @reserved2: reserved.
+ * @ep_sts_en: DMA endpoint status enable register.
+ * @drbl: DMA doorbell register.
+ * @ep_ien: DMA endpoint interrupt enable register.
+ * @ep_ists: DMA endpoint interrupt status register.
+ * @axim_ctrl: AXI Master Control register.
+ * @axim_id: AXI Master ID register.
+ * @reserved3: reserved.
+ * @axim_cap: AXI Master Wrapper Extended Capability.
+ * @reserved4: reserved.
+ * @axim_ctrl0: AXI Master Wrapper Extended Capability Control Register 0.
+ * @axim_ctrl1: AXI Master Wrapper Extended Capability Control Register 1.
+ */
+struct cdns2_adma_regs {
+	__le32 conf;
+	__le32 sts;
+	__le32 reserved1[5];
+	__le32 ep_sel;
+	__le32 ep_traddr;
+	__le32 ep_cfg;
+	__le32 ep_cmd;
+	__le32 ep_sts;
+	__le32 reserved2;
+	__le32 ep_sts_en;
+	__le32 drbl;
+	__le32 ep_ien;
+	__le32 ep_ists;
+	__le32 axim_ctrl;
+	__le32 axim_id;
+	__le32 reserved3;
+	__le32 axim_cap;
+	__le32 reserved4;
+	__le32 axim_ctrl0;
+	__le32 axim_ctrl1;
+};
+
+#define CDNS2_ADMA_REGS_OFFSET	0x400
+
+/* DMA_CONF - bitmasks. */
+/* Reset USB device configuration. */
+#define DMA_CONF_CFGRST		BIT(0)
+/* Singular DMA transfer mode.*/
+#define DMA_CONF_DSING		BIT(8)
+/* Multiple DMA transfers mode.*/
+#define DMA_CONF_DMULT		BIT(9)
+
+/* DMA_EP_CFG - bitmasks. */
+/* Endpoint enable. */
+#define DMA_EP_CFG_ENABLE	BIT(0)
+
+/* DMA_EP_CMD - bitmasks. */
+/* Endpoint reset. */
+#define DMA_EP_CMD_EPRST	BIT(0)
+/* Transfer descriptor ready. */
+#define DMA_EP_CMD_DRDY		BIT(6)
+/* Data flush. */
+#define DMA_EP_CMD_DFLUSH	BIT(7)
+
+/* DMA_EP_STS - bitmasks. */
+/* Interrupt On Complete. */
+#define DMA_EP_STS_IOC		BIT(2)
+/* Interrupt on Short Packet. */
+#define DMA_EP_STS_ISP		BIT(3)
+/* Transfer descriptor missing. */
+#define DMA_EP_STS_DESCMIS	BIT(4)
+/* TRB error. */
+#define DMA_EP_STS_TRBERR	BIT(7)
+/* DMA busy bit. */
+#define DMA_EP_STS_DBUSY	BIT(9)
+/* Current Cycle Status. */
+#define DMA_EP_STS_CCS(p)	((p) & BIT(11))
+/* OUT size mismatch. */
+#define DMA_EP_STS_OUTSMM	BIT(14)
+/* ISO transmission error. */
+#define DMA_EP_STS_ISOERR	BIT(15)
+
+/* DMA_EP_STS_EN - bitmasks. */
+/* OUT transfer missing descriptor enable. */
+#define DMA_EP_STS_EN_DESCMISEN	BIT(4)
+/* TRB enable. */
+#define DMA_EP_STS_EN_TRBERREN	BIT(7)
+/* OUT size mismatch enable. */
+#define DMA_EP_STS_EN_OUTSMMEN	BIT(14)
+/* ISO transmission error enable. */
+#define DMA_EP_STS_EN_ISOERREN	BIT(15)
+
+/* DMA_EP_IEN - bitmasks. */
+#define DMA_EP_IEN(index)	(1 << (index))
+#define DMA_EP_IEN_EP_OUT0	BIT(0)
+#define DMA_EP_IEN_EP_IN0	BIT(16)
+
+/* DMA_EP_ISTS - bitmasks. */
+#define DMA_EP_ISTS(index)	(1 << (index))
+#define DMA_EP_ISTS_EP_OUT0	BIT(0)
+#define DMA_EP_ISTS_EP_IN0	BIT(16)
+
+#define gadget_to_cdns2_device(g) (container_of(g, struct cdns2_device, gadget))
+#define ep_to_cdns2_ep(ep) (container_of(ep, struct cdns2_endpoint, endpoint))
+
+/*-------------------------------------------------------------------------*/
+#define TRBS_PER_SEGMENT	600
+#define ISO_MAX_INTERVAL	8
+#define MAX_TRB_LENGTH		BIT(16)
+#define MAX_ISO_SIZE		3076
+/*
+ * To improve performance the TRB buffer pointers can't cross
+ * 4KB boundaries.
+ */
+#define TRB_MAX_ISO_BUFF_SHIFT	12
+#define TRB_MAX_ISO_BUFF_SIZE	BIT(TRB_MAX_ISO_BUFF_SHIFT)
+/* How much data is left before the 4KB boundary? */
+#define TRB_BUFF_LEN_UP_TO_BOUNDARY(addr) (TRB_MAX_ISO_BUFF_SIZE - \
+					((addr) & (TRB_MAX_ISO_BUFF_SIZE - 1)))
+
+#if TRBS_PER_SEGMENT < 2
+#error "Incorrect TRBS_PER_SEGMENT. Minimal Transfer Ring size is 2."
+#endif
+
+/**
+ * struct cdns2_trb - represent Transfer Descriptor block.
+ * @buffer: pointer to buffer data.
+ * @length: length of data.
+ * @control: control flags.
+ *
+ * This structure describes transfer block handled by DMA module.
+ */
+struct cdns2_trb {
+	__le32 buffer;
+	__le32 length;
+	__le32 control;
+};
+
+#define TRB_SIZE		(sizeof(struct cdns2_trb))
+/*
+ * These two extra TRBs are reserved for isochronous transfer
+ * to inject 0 length packet and extra LINK TRB to synchronize the ISO transfer.
+ */
+#define TRB_ISO_RESERVED	2
+#define TR_SEG_SIZE		(TRB_SIZE * (TRBS_PER_SEGMENT + TRB_ISO_RESERVED))
+
+/* TRB bit mask. */
+#define TRB_TYPE_BITMASK	GENMASK(15, 10)
+#define TRB_TYPE(p)		((p) << 10)
+#define TRB_FIELD_TO_TYPE(p)	(((p) & TRB_TYPE_BITMASK) >> 10)
+
+/* TRB type IDs. */
+/* Used for Bulk, Interrupt, ISOC, and control data stage. */
+#define TRB_NORMAL		1
+/* TRB for linking ring segments. */
+#define TRB_LINK		6
+
+/* Cycle bit - indicates TRB ownership by driver or hw. */
+#define TRB_CYCLE		BIT(0)
+/*
+ * When set to '1', the device will toggle its interpretation of the Cycle bit.
+ */
+#define TRB_TOGGLE		BIT(1)
+/* Interrupt on short packet. */
+#define TRB_ISP			BIT(2)
+/* Chain bit associate this TRB with next one TRB. */
+#define TRB_CHAIN		BIT(4)
+/* Interrupt on completion. */
+#define TRB_IOC			BIT(5)
+
+/* Transfer_len bitmasks. */
+#define TRB_LEN(p)		((p) & GENMASK(16, 0))
+#define TRB_BURST(p)		(((p) << 24) & GENMASK(31, 24))
+#define TRB_FIELD_TO_BURST(p)	(((p) & GENMASK(31, 24)) >> 24)
+
+/* Data buffer pointer bitmasks. */
+#define TRB_BUFFER(p)		((p) & GENMASK(31, 0))
+
+/*-------------------------------------------------------------------------*/
+/* Driver numeric constants. */
+
+/* Maximum address that can be assigned to device. */
+#define USB_DEVICE_MAX_ADDRESS	127
+
+/* One control and 15 IN and 15 OUT endpoints. */
+#define CDNS2_ENDPOINTS_NUM	31
+
+#define CDNS2_EP_ZLP_BUF_SIZE	512
+
+/*-------------------------------------------------------------------------*/
+/* Used structures. */
+
+struct cdns2_device;
+
+/**
+ * struct cdns2_ring - transfer ring representation.
+ * @trbs: pointer to transfer ring.
+ * @dma: dma address of transfer ring.
+ * @free_trbs: number of free TRBs in transfer ring.
+ * @pcs: producer cycle state.
+ * @ccs: consumer cycle state.
+ * @enqueue: enqueue index in transfer ring.
+ * @dequeue: dequeue index in transfer ring.
+ */
+struct cdns2_ring {
+	struct cdns2_trb *trbs;
+	dma_addr_t dma;
+	int free_trbs;
+	u8 pcs;
+	u8 ccs;
+	int enqueue;
+	int dequeue;
+};
+
+/**
+ * struct cdns2_endpoint - extended device side representation of USB endpoint.
+ * @endpoint: usb endpoint.
+ * @pending_list: list of requests queuing on transfer ring.
+ * @deferred_list: list of requests waiting for queuing on transfer ring.
+ * @pdev: device associated with endpoint.
+ * @name: a human readable name e.g. ep1out.
+ * @ring: transfer ring associated with endpoint.
+ * @ep_state: state of endpoint.
+ * @idx: index of endpoint in pdev->eps table.
+ * @dir: endpoint direction.
+ * @num: endpoint number (1 - 15).
+ * @type: set to bmAttributes & USB_ENDPOINT_XFERTYPE_MASK.
+ * @interval: interval between packets used for ISOC and Interrupt endpoint.
+ * @buffering: on-chip buffers assigned to endpoint.
+ * @trb_burst_size: number of burst used in TRB.
+ * @skip: Sometimes the controller cannot process isochronous endpoint ring
+ *        quickly enough and it will miss some isoc tds on the ring and
+ *        generate ISO transmition error.
+ *        Driver sets skip flag when receive a ISO transmition error and
+ *        process the missed TDs on the endpoint ring.
+ * @wa1_set: use WA1.
+ * @wa1_trb: TRB assigned to WA1.
+ * @wa1_trb_index: TRB index for WA1.
+ * @wa1_cycle_bit: correct cycle bit for WA1.
+ */
+struct cdns2_endpoint {
+	struct usb_ep endpoint;
+	struct list_head pending_list;
+	struct list_head deferred_list;
+
+	struct cdns2_device	*pdev;
+	char name[20];
+
+	struct cdns2_ring ring;
+
+#define EP_ENABLED		BIT(0)
+#define EP_STALLED		BIT(1)
+#define EP_STALL_PENDING	BIT(2)
+#define EP_WEDGE		BIT(3)
+#define	EP_CLAIMED		BIT(4)
+#define EP_RING_FULL		BIT(5)
+#define EP_DEFERRED_DRDY	BIT(6)
+
+	u32 ep_state;
+
+	u8 idx;
+	u8 dir;
+	u8 num;
+	u8 type;
+	int interval;
+	u8 buffering;
+	u8 trb_burst_size;
+	bool skip;
+
+	unsigned int wa1_set:1;
+	struct cdns2_trb *wa1_trb;
+	unsigned int wa1_trb_index;
+	unsigned int wa1_cycle_bit:1;
+};
+
+/**
+ * struct cdns2_request - extended device side representation of usb_request
+ *                        object.
+ * @request: generic usb_request object describing single I/O request.
+ * @pep: extended representation of usb_ep object.
+ * @trb: the first TRB association with this request.
+ * @start_trb: number of the first TRB in transfer ring.
+ * @end_trb: number of the last TRB in transfer ring.
+ * @list: used for queuing request in lists.
+ * @finished_trb: number of trb has already finished per request.
+ * @num_of_trb: how many trbs are associated with request.
+ */
+struct cdns2_request {
+	struct usb_request request;
+	struct cdns2_endpoint *pep;
+	struct cdns2_trb *trb;
+	int start_trb;
+	int end_trb;
+	struct list_head list;
+	int finished_trb;
+	int num_of_trb;
+};
+
+#define to_cdns2_request(r) (container_of(r, struct cdns2_request, request))
+
+/* Stages used during enumeration process.*/
+#define CDNS2_SETUP_STAGE		0x0
+#define CDNS2_DATA_STAGE		0x1
+#define CDNS2_STATUS_STAGE		0x2
+
+/**
+ * struct cdns2_device - represent USB device.
+ * @dev: pointer to device structure associated whit this controller.
+ * @gadget: device side representation of the peripheral controller.
+ * @gadget_driver: pointer to the gadget driver.
+ * @lock: for synchronizing.
+ * @irq: interrupt line number.
+ * @regs: base address for registers
+ * @usb_regs: base address for common USB registers.
+ * @ep0_regs: base address for endpoint 0 related registers.
+ * @epx_regs: base address for all none control endpoint registers.
+ * @interrupt_regs: base address for interrupt handling related registers.
+ * @adma_regs: base address for ADMA registers.
+ * @eps_dma_pool: endpoint Transfer Ring pool.
+ * @setup: used while processing usb control requests.
+ * @ep0_preq: private request used while handling EP0.
+ * @ep0_stage: ep0 stage during enumeration process.
+ * @zlp_buf: zlp buffer.
+ * @dev_address: device address assigned by host.
+ * @eps: array of objects describing endpoints.
+ * @selected_ep: actually selected endpoint. It's used only to improve
+ *      performance by limiting access to dma_ep_sel register.
+ * @is_selfpowered: device is self powered.
+ * @may_wakeup: allows device to remote wakeup the host.
+ * @status_completion_no_call: indicate that driver is waiting for status
+ *      stage completion. It's used in deferred SET_CONFIGURATION request.
+ * @in_lpm: indicate the controller is in low power mode.
+ * @pending_status_wq: workqueue handling status stage for deferred requests.
+ * @pending_status_request: request for which status stage was deferred.
+ * @eps_supported: endpoints supported by controller in form:
+ *      bit: 0 - ep0, 1 - epOut1, 2 - epIn1, 3 - epOut2 ...
+ * @burst_opt: array with the best burst size value for different TRB size.
+ * @onchip_tx_buf: size of transmit on-chip buffer in KB.
+ * @onchip_rx_buf: size of receive on-chip buffer in KB.
+ */
+struct cdns2_device {
+	struct device *dev;
+	struct usb_gadget gadget;
+	struct usb_gadget_driver *gadget_driver;
+
+	/* generic spin-lock for drivers */
+	spinlock_t lock;
+	int irq;
+	void __iomem *regs;
+	struct cdns2_usb_regs __iomem *usb_regs;
+	struct cdns2_ep0_regs __iomem *ep0_regs;
+	struct cdns2_epx_regs __iomem *epx_regs;
+	struct cdns2_interrupt_regs __iomem *interrupt_regs;
+	struct cdns2_adma_regs __iomem *adma_regs;
+	struct dma_pool *eps_dma_pool;
+	struct usb_ctrlrequest setup;
+	struct cdns2_request ep0_preq;
+	u8 ep0_stage;
+	void *zlp_buf;
+	u8 dev_address;
+	struct cdns2_endpoint eps[CDNS2_ENDPOINTS_NUM];
+	u32 selected_ep;
+	bool is_selfpowered;
+	bool may_wakeup;
+	bool status_completion_no_call;
+	bool in_lpm;
+	struct work_struct pending_status_wq;
+	struct usb_request *pending_status_request;
+	u32 eps_supported;
+	u8 burst_opt[MAX_ISO_SIZE + 1];
+
+	/*in KB */
+	u16 onchip_tx_buf;
+	u16 onchip_rx_buf;
+};
+
+#define CDNS2_IF_EP_EXIST(pdev, ep_num, dir) \
+			 ((pdev)->eps_supported & \
+			 (BIT(ep_num) << ((dir) ? 0 : 16)))
+
+dma_addr_t cdns2_trb_virt_to_dma(struct cdns2_endpoint *pep,
+				 struct cdns2_trb *trb);
+void cdns2_pending_setup_status_handler(struct work_struct *work);
+void cdns2_select_ep(struct cdns2_device *pdev, u32 ep);
+struct cdns2_request *cdns2_next_preq(struct list_head *list);
+struct usb_request *cdns2_gadget_ep_alloc_request(struct usb_ep *ep,
+						  gfp_t gfp_flags);
+void cdns2_gadget_ep_free_request(struct usb_ep *ep,
+				  struct usb_request *request);
+int cdns2_gadget_ep_dequeue(struct usb_ep *ep, struct usb_request *request);
+void cdns2_gadget_giveback(struct cdns2_endpoint *pep,
+			   struct cdns2_request *priv_req,
+			   int status);
+void cdns2_init_ep0(struct cdns2_device *pdev, struct cdns2_endpoint *pep);
+void cdns2_ep0_config(struct cdns2_device *pdev);
+void cdns2_handle_ep0_interrupt(struct cdns2_device *pdev, int dir);
+void cdns2_handle_setup_packet(struct cdns2_device *pdev);
+int cdns2_gadget_resume(struct cdns2_device *pdev, bool hibernated);
+int cdns2_gadget_suspend(struct cdns2_device *pdev);
+void cdns2_gadget_remove(struct cdns2_device *pdev);
+int cdns2_gadget_init(struct cdns2_device *pdev);
+void set_reg_bit_8(void __iomem *ptr, u8 mask);
+int cdns2_halt_endpoint(struct cdns2_device *pdev, struct cdns2_endpoint *pep,
+			int value);
+
+#endif /* __LINUX_CDNS2_GADGET */
-- 
2.37.2