/* * (C) Copyright 2003 * Gleb Natapov <gnatapov@mrv.com> * Some bits are taken from linux driver writen by adrian@humboldt.co.uk * * Hardware I2C driver for MPC107 PCI bridge. * * See file CREDITS for list of people who contributed to this * project. * * 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. * * 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. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, * MA 02111-1307 USA */#include <common.h>#undef I2CDBG#ifdef CONFIG_HARD_I2C#include <i2c.h>#define TIMEOUT (CFG_HZ/4)#define I2C_Addr ((unsigned *)(CFG_EUMB_ADDR + 0x3000))#define I2CADR &I2C_Addr[0]#define I2CFDR  &I2C_Addr[1]#define I2CCCR  &I2C_Addr[2]#define I2CCSR  &I2C_Addr[3]#define I2CCDR  &I2C_Addr[4]#define MPC107_CCR_MEN  0x80#define MPC107_CCR_MIEN 0x40#define MPC107_CCR_MSTA 0x20#define MPC107_CCR_MTX  0x10#define MPC107_CCR_TXAK 0x08#define MPC107_CCR_RSTA 0x04#define MPC107_CSR_MCF  0x80#define MPC107_CSR_MAAS 0x40#define MPC107_CSR_MBB  0x20#define MPC107_CSR_MAL  0x10#define MPC107_CSR_SRW  0x04#define MPC107_CSR_MIF  0x02#define MPC107_CSR_RXAK 0x01#define I2C_READ  1#define I2C_WRITE 0/* taken from linux include/asm-ppc/io.h */inline unsigned in_le32 (volatile unsigned *addr){	unsigned ret;	__asm__ __volatile__ ("lwbrx %0,0,%1;\n"			      "twi 0,%0,0;\n"			      "isync":"=r" (ret): "r" (addr), "m" (*addr));	return ret;}inline void out_le32 (volatile unsigned *addr, int val){	__asm__ __volatile__ ("stwbrx %1,0,%2; eieio":"=m" (*addr):"r" (val),			      "r" (addr));}#define writel(val, addr) out_le32(addr, val)#define readl(addr) in_le32(addr)void i2c_init (int speed, int slaveadd){	/* stop I2C controller */	writel (0x0, I2CCCR);	/* set clock */	writel (0x1020, I2CFDR);	/* write slave address */	writel (slaveadd, I2CADR);	/* clear status register */	writel (0x0, I2CCSR);	/* start I2C controller */	writel (MPC107_CCR_MEN, I2CCCR);	return;}static __inline__ int i2c_wait4bus (void){	ulong timeval = get_timer (0);	while (readl (I2CCSR) & MPC107_CSR_MBB)		if (get_timer (timeval) > TIMEOUT)			return -1;	return 0;}static __inline__ int i2c_wait (int write){	u32 csr;	ulong timeval = get_timer (0);	do {		csr = readl (I2CCSR);		if (!(csr & MPC107_CSR_MIF))			continue;		writel (0x0, I2CCSR);		if (csr & MPC107_CSR_MAL) {#ifdef I2CDBG			printf ("i2c_wait: MAL\n");#endif			return -1;		}		if (!(csr & MPC107_CSR_MCF)) {#ifdef I2CDBG			printf ("i2c_wait: unfinished\n");#endif			return -1;		}		if (write == I2C_WRITE && (csr & MPC107_CSR_RXAK)) {#ifdef I2CDBG			printf ("i2c_wait: No RXACK\n");#endif			return -1;		}		return 0;	} while (get_timer (timeval) < TIMEOUT);#ifdef I2CDBG	printf ("i2c_wait: timed out\n");#endif	return -1;}static __inline__ int i2c_write_addr (u8 dev, u8 dir, int rsta){	writel (MPC107_CCR_MEN | MPC107_CCR_MSTA | MPC107_CCR_MTX |		(rsta ? MPC107_CCR_RSTA : 0), I2CCCR);	writel ((dev << 1) | dir, I2CCDR);	if (i2c_wait (I2C_WRITE) < 0)		return 0;	return 1;}static __inline__ int __i2c_write (u8 * data, int length){	int i;	writel (MPC107_CCR_MEN | MPC107_CCR_MSTA | MPC107_CCR_MTX, I2CCCR);	for (i = 0; i < length; i++) {		writel (data[i], I2CCDR);		if (i2c_wait (I2C_WRITE) < 0)			break;	}	return i;}static __inline__ int __i2c_read (u8 * data, int length){	int i;	writel (MPC107_CCR_MEN | MPC107_CCR_MSTA |		((length == 1) ? MPC107_CCR_TXAK : 0), I2CCCR);	/* dummy read */	readl (I2CCDR);	for (i = 0; i < length; i++) {		if (i2c_wait (I2C_READ) < 0)			break;		/* Generate ack on last next to last byte */		if (i == length - 2)			writel (MPC107_CCR_MEN | MPC107_CCR_MSTA |				MPC107_CCR_TXAK, I2CCCR);		/* Generate stop on last byte */		if (i == length - 1)			writel (MPC107_CCR_MEN | MPC107_CCR_TXAK, I2CCCR);		data[i] = readl (I2CCDR);	}	return i;}int i2c_read (u8 dev, uint addr, int alen, u8 * data, int length){	int i = 0;	u8 *a = (u8 *) & addr;	if (i2c_wait4bus () < 0)		goto exit;	if (i2c_write_addr (dev, I2C_WRITE, 0) == 0)		goto exit;	if (__i2c_write (&a[4 - alen], alen) != alen)		goto exit;	if (i2c_write_addr (dev, I2C_READ, 1) == 0)		goto exit;	i = __i2c_read (data, length);exit:	writel (MPC107_CCR_MEN, I2CCCR);	return !(i == length);}int i2c_write (u8 dev, uint addr, int alen, u8 * data, int length){	int i = 0;	u8 *a = (u8 *) & addr;	if (i2c_wait4bus () < 0)		goto exit;	if (i2c_write_addr (dev, I2C_WRITE, 0) == 0)		goto exit;	if (__i2c_write (&a[4 - alen], alen) != alen)		goto exit;	i = __i2c_write (data, length);exit:	writel (MPC107_CCR_MEN, I2CCCR);	return !(i == length);}int i2c_probe (uchar chip){	int tmp;	/*	 * Try to read the first location of the chip.  The underlying	 * driver doesn't appear to support sending just the chip address	 * and looking for an <ACK> back.	 */	udelay (10000);	return i2c_read (chip, 0, 1, (uchar *) &tmp, 1);}uchar i2c_reg_read (uchar i2c_addr, uchar reg){	uchar buf[1];	i2c_read (i2c_addr, reg, 1, buf, 1);	return (buf[0]);}void i2c_reg_write (uchar i2c_addr, uchar reg, uchar val){	i2c_write (i2c_addr, reg, 1, &val, 1);}#endif /* CONFIG_HARD_I2C */