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/*
* This file is part of the coreboot project.
*
* Copyright (C) 2013 Alexandru Gagniuc <mr.nuke.me@gmail.com>
*
* 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; version 2 of the License or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* Definitions Two Wire Interface (TWI) (I²C) Allwinner CPUs
*/
#ifndef CPU_ALLWINNER_A10_TWI_H
#define CPU_ALLWINNER_A10_TWI_H
#include <types.h>
/* TWI_CTL values */
#define TWI_CTL_INT_EN (1 << 7)
#define TWI_CTL_BUS_EN (1 << 6)
#define TWI_CTL_M_START (1 << 5)
#define TWI_CTL_M_STOP (1 << 4)
#define TWI_CTL_INT_FLAG (1 << 3)
#define TWI_CTL_A_ACK (1 << 2)
/* TWI_STAT values */
enum twi_status {
TWI_STAT_BUS_ERROR = 0x00, /**< Bus error */
TWI_STAT_TX_START = 0x08, /**< START sent */
TWI_STAT_TX_RSTART = 0x10, /**< Repeated START sent */
TWI_STAT_TX_AW_ACK = 0x18, /**< Sent address+read, ACK */
TWI_STAT_TX_AW_NAK = 0x20, /**< Sent address+read, NAK */
TWI_STAT_TXD_ACK = 0x28, /**< Sent data, got ACK */
TWI_STAT_TXD_NAK = 0x30, /**< Sent data, no ACK */
TWI_STAT_LOST_ARB = 0x38, /**< Lost arbitration */
TWI_STAT_TX_AR_ACK = 0x40, /**< Sent address+write, ACK */
TWI_STAT_TX_AR_NAK = 0x48, /**< Sent address+write, NAK */
TWI_STAT_RXD_ACK = 0x50, /**< Got data, sent ACK */
TWI_STAT_RXD_NAK = 0x58, /**< Got data, no ACK */
TWI_STAT_IDLE = 0xf8, /**< Bus idle*/
};
/* TWI_CLK values */
#define TWI_CLK_M_MASK (0xf << 3)
#define TWI_CLK_M(m) (((m - 1) << 3) & TWI_CLK_M_MASK)
#define TWI_CLK_N_MASK (0x7 << 0)
#define TWI_CLK_N(n) ((n) & TWI_CLK_N_MASK)
struct a1x_twi {
u32 addr; /**< 0x00: Slave address */
u32 xaddr; /**< 0x04: Extended slave address */
u32 data; /**< 0x08: Data byte */
u32 ctl; /**< 0x0C: Control register */
u32 stat; /**< 0x10: Status register */
u32 clk; /**< 0x14: Clock control register */
u32 reset; /**< 0x18: Software reset */
u32 efr; /**< 0x1C: Enhanced Feature register */
u32 lcr; /**< 0x20: Line control register */
};
void a1x_twi_init(u8 bus, u32 speed_hz);
#endif /* CPU_ALLWINNER_A10_TWI_H */
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