arch/blackfin/include/asm/bfin_twi.h

/*
 * bfin_twi.h - interface to Blackfin TWIs
 *
 * Copyright 2005-2014 Analog Devices Inc.
 *
 * Licensed under the GPL-2 or later.
 */

#ifndef __ASM_BFIN_TWI_H__
#define __ASM_BFIN_TWI_H__

#include <asm/blackfin.h>
#include <linux/types.h>
#include <linux/i2c.h>

/*
 * ADI twi registers layout
 */
struct bfin_twi_regs {
	u16 clkdiv;
	u16 dummy1;
	u16 control;
	u16 dummy2;
	u16 slave_ctl;
	u16 dummy3;
	u16 slave_stat;
	u16 dummy4;
	u16 slave_addr;
	u16 dummy5;
	u16 master_ctl;
	u16 dummy6;
	u16 master_stat;
	u16 dummy7;
	u16 master_addr;
	u16 dummy8;
	u16 int_stat;
	u16 dummy9;
	u16 int_mask;
	u16 dummy10;
	u16 fifo_ctl;
	u16 dummy11;
	u16 fifo_stat;
	u16 dummy12;
	u32 __pad[20];
	u16 xmt_data8;
	u16 dummy13;
	u16 xmt_data16;
	u16 dummy14;
	u16 rcv_data8;
	u16 dummy15;
	u16 rcv_data16;
	u16 dummy16;
};

struct bfin_twi_iface {
	int			irq;
	spinlock_t		lock;
	char			read_write;
	u8			command;
	u8			*transPtr;
	int			readNum;
	int			writeNum;
	int			cur_mode;
	int			manual_stop;
	int			result;
	struct i2c_adapter	adap;
	struct completion	complete;
	struct i2c_msg		*pmsg;
	int			msg_num;
	int			cur_msg;
	u16			saved_clkdiv;
	u16			saved_control;
	struct bfin_twi_regs __iomem *regs_base;
};

/*  ********************  TWO-WIRE INTERFACE (TWI) MASKS  ********************/
/* TWI_CLKDIV Macros (Use: *pTWI_CLKDIV = CLKLOW(x)|CLKHI(y);  ) */
#define	CLKLOW(x)	((x) & 0xFF)	/* Periods Clock Is Held Low */
#define CLKHI(y)	(((y)&0xFF)<<0x8) /* Periods Before New Clock Low */

/* TWI_PRESCALE Masks */
#define	PRESCALE	0x007F	/* SCLKs Per Internal Time Reference (10MHz) */
#define	TWI_ENA		0x0080	/* TWI Enable */
#define	SCCB		0x0200	/* SCCB Compatibility Enable */

/* TWI_SLAVE_CTL Masks */
#define	SEN		0x0001	/* Slave Enable */
#define	SADD_LEN	0x0002	/* Slave Address Length */
#define	STDVAL		0x0004	/* Slave Transmit Data Valid */
#define	NAK		0x0008	/* NAK Generated At Conclusion Of Transfer */
#define	GEN		0x0010	/* General Call Address Matching Enabled */

/* TWI_SLAVE_STAT Masks	*/
#define	SDIR		0x0001	/* Slave Transfer Direction (RX/TX*) */
#define GCALL		0x0002	/* General Call Indicator */

/* TWI_MASTER_CTL Masks	*/
#define	MEN		0x0001	/* Master Mode Enable          */
#define	MADD_LEN	0x0002	/* Master Address Length       */
#define	MDIR		0x0004	/* Master Transmit Direction (RX/TX*) */
#define	FAST		0x0008	/* Use Fast Mode Timing Specs  */
#define	STOP		0x0010	/* Issue Stop Condition        */
#define	RSTART		0x0020	/* Repeat Start or Stop* At End Of Transfer */
#define	DCNT		0x3FC0	/* Data Bytes To Transfer      */
#define	SDAOVR		0x4000	/* Serial Data Override        */
#define	SCLOVR		0x8000	/* Serial Clock Override       */

/* TWI_MASTER_STAT Masks */
#define	MPROG		0x0001	/* Master Transfer In Progress */
#define	LOSTARB		0x0002	/* Lost Arbitration Indicator (Xfer Aborted) */
#define	ANAK		0x0004	/* Address Not Acknowledged    */
#define	DNAK		0x0008	/* Data Not Acknowledged       */
#define	BUFRDERR	0x0010	/* Buffer Read Error           */
#define	BUFWRERR	0x0020	/* Buffer Write Error          */
#define	SDASEN		0x0040	/* Serial Data Sense           */
#define	SCLSEN		0x0080	/* Serial Clock Sense          */
#define	BUSBUSY		0x0100	/* Bus Busy Indicator          */

/* TWI_INT_SRC and TWI_INT_ENABLE Masks	*/
#define	SINIT		0x0001	/* Slave Transfer Initiated    */
#define	SCOMP		0x0002	/* Slave Transfer Complete     */
#define	SERR		0x0004	/* Slave Transfer Error        */
#define	SOVF		0x0008	/* Slave Overflow              */
#define	MCOMP		0x0010	/* Master Transfer Complete    */
#define	MERR		0x0020	/* Master Transfer Error       */
#define	XMTSERV		0x0040	/* Transmit FIFO Service       */
#define	RCVSERV		0x0080	/* Receive FIFO Service        */

/* TWI_FIFO_CTRL Masks */
#define	XMTFLUSH	0x0001	/* Transmit Buffer Flush                 */
#define	RCVFLUSH	0x0002	/* Receive Buffer Flush                  */
#define	XMTINTLEN	0x0004	/* Transmit Buffer Interrupt Length      */
#define	RCVINTLEN	0x0008	/* Receive Buffer Interrupt Length       */

/* TWI_FIFO_STAT Masks */
#define	XMTSTAT		0x0003	/* Transmit FIFO Status                  */
#define	XMT_EMPTY	0x0000	/* Transmit FIFO Empty                   */
#define	XMT_HALF	0x0001	/* Transmit FIFO Has 1 Byte To Write     */
#define	XMT_FULL	0x0003	/* Transmit FIFO Full (2 Bytes To Write) */

#define	RCVSTAT		0x000C	/* Receive FIFO Status                   */
#define	RCV_EMPTY	0x0000	/* Receive FIFO Empty                    */
#define	RCV_HALF	0x0004	/* Receive FIFO Has 1 Byte To Read       */
#define	RCV_FULL	0x000C	/* Receive FIFO Full (2 Bytes To Read)   */

#define DEFINE_TWI_REG(reg_name, reg) \
static inline u16 read_##reg_name(struct bfin_twi_iface *iface) \
	{ return bfin_read16(&iface->regs_base->reg); } \
static inline void write_##reg_name(struct bfin_twi_iface *iface, u16 v) \
	{ bfin_write16(&iface->regs_base->reg, v); }

DEFINE_TWI_REG(CLKDIV, clkdiv)
DEFINE_TWI_REG(SLAVE_CTL, slave_ctl)
DEFINE_TWI_REG(SLAVE_STAT, slave_stat)
DEFINE_TWI_REG(SLAVE_ADDR, slave_addr)
DEFINE_TWI_REG(MASTER_CTL, master_ctl)
DEFINE_TWI_REG(MASTER_STAT, master_stat)
DEFINE_TWI_REG(MASTER_ADDR, master_addr)
DEFINE_TWI_REG(INT_STAT, int_stat)
DEFINE_TWI_REG(INT_MASK, int_mask)
DEFINE_TWI_REG(FIFO_STAT, fifo_stat)
DEFINE_TWI_REG(XMT_DATA8, xmt_data8)
DEFINE_TWI_REG(XMT_DATA16, xmt_data16)
#if !ANOMALY_16000030
DEFINE_TWI_REG(RCV_DATA8, rcv_data8)
DEFINE_TWI_REG(RCV_DATA16, rcv_data16)
#else
static inline u16 read_RCV_DATA8(struct bfin_twi_iface *iface)
{
	u16 ret;
	unsigned long flags;

	flags = hard_local_irq_save();
	ret = bfin_read16(&iface->regs_base->rcv_data8);
	hard_local_irq_restore(flags);

	return ret;
}

static inline u16 read_RCV_DATA16(struct bfin_twi_iface *iface)
{
	u16 ret;
	unsigned long flags;

	flags = hard_local_irq_save();
	ret = bfin_read16(&iface->regs_base->rcv_data16);
	hard_local_irq_restore(flags);

	return ret;
}
#endif

static inline u16 read_FIFO_CTL(struct bfin_twi_iface *iface)
{
	return bfin_read16(&iface->regs_base->fifo_ctl);
}

static inline void write_FIFO_CTL(struct bfin_twi_iface *iface, u16 v)
{
	bfin_write16(&iface->regs_base->fifo_ctl, v);
	SSYNC();
}

static inline u16 read_CONTROL(struct bfin_twi_iface *iface)
{
	return bfin_read16(&iface->regs_base->control);
}

static inline void write_CONTROL(struct bfin_twi_iface *iface, u16 v)
{
	SSYNC();
	bfin_write16(&iface->regs_base->control, v);
}
#endif