u-boot/drivers/i2c/sh_sh7734_i2c.c

388 lines
8 KiB
C
Raw Normal View History

/*
* Copyright (C) 2012 Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
* Copyright (C) 2012 Renesas Solutions Corp.
*
* 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>
#include <i2c.h>
#include <asm/io.h>
struct sh_i2c {
u8 iccr1;
u8 iccr2;
u8 icmr;
u8 icier;
u8 icsr;
u8 sar;
u8 icdrt;
u8 icdrr;
u8 nf2cyc;
u8 __pad0;
u8 __pad1;
};
static struct sh_i2c *base;
static u8 iccr1_cks, nf2cyc;
/* ICCR1 */
#define SH_I2C_ICCR1_ICE (1 << 7)
#define SH_I2C_ICCR1_RCVD (1 << 6)
#define SH_I2C_ICCR1_MST (1 << 5)
#define SH_I2C_ICCR1_TRS (1 << 4)
#define SH_I2C_ICCR1_MTRS \
(SH_I2C_ICCR1_MST | SH_I2C_ICCR1_TRS)
/* ICCR1 */
#define SH_I2C_ICCR2_BBSY (1 << 7)
#define SH_I2C_ICCR2_SCP (1 << 6)
#define SH_I2C_ICCR2_SDAO (1 << 5)
#define SH_I2C_ICCR2_SDAOP (1 << 4)
#define SH_I2C_ICCR2_SCLO (1 << 3)
#define SH_I2C_ICCR2_IICRST (1 << 1)
#define SH_I2C_ICIER_TIE (1 << 7)
#define SH_I2C_ICIER_TEIE (1 << 6)
#define SH_I2C_ICIER_RIE (1 << 5)
#define SH_I2C_ICIER_NAKIE (1 << 4)
#define SH_I2C_ICIER_STIE (1 << 3)
#define SH_I2C_ICIER_ACKE (1 << 2)
#define SH_I2C_ICIER_ACKBR (1 << 1)
#define SH_I2C_ICIER_ACKBT (1 << 0)
#define SH_I2C_ICSR_TDRE (1 << 7)
#define SH_I2C_ICSR_TEND (1 << 6)
#define SH_I2C_ICSR_RDRF (1 << 5)
#define SH_I2C_ICSR_NACKF (1 << 4)
#define SH_I2C_ICSR_STOP (1 << 3)
#define SH_I2C_ICSR_ALOVE (1 << 2)
#define SH_I2C_ICSR_AAS (1 << 1)
#define SH_I2C_ICSR_ADZ (1 << 0)
#define IRQ_WAIT 1000
static void sh_i2c_send_stop(struct sh_i2c *base)
{
clrbits_8(&base->iccr2, SH_I2C_ICCR2_BBSY | SH_I2C_ICCR2_SCP);
}
static int check_icsr_bits(struct sh_i2c *base, u8 bits)
{
int i;
for (i = 0; i < IRQ_WAIT; i++) {
if (bits & readb(&base->icsr))
return 0;
udelay(10);
}
return 1;
}
static int check_stop(struct sh_i2c *base)
{
int ret = check_icsr_bits(base, SH_I2C_ICSR_STOP);
clrbits_8(&base->icsr, SH_I2C_ICSR_STOP);
return ret;
}
static int check_tend(struct sh_i2c *base, int stop)
{
int ret = check_icsr_bits(base, SH_I2C_ICSR_TEND);
if (stop) {
clrbits_8(&base->icsr, SH_I2C_ICSR_STOP);
sh_i2c_send_stop(base);
}
clrbits_8(&base->icsr, SH_I2C_ICSR_TEND);
return ret;
}
static int check_tdre(struct sh_i2c *base)
{
return check_icsr_bits(base, SH_I2C_ICSR_TDRE);
}
static int check_rdrf(struct sh_i2c *base)
{
return check_icsr_bits(base, SH_I2C_ICSR_RDRF);
}
static int check_bbsy(struct sh_i2c *base)
{
int i;
for (i = 0 ; i < IRQ_WAIT ; i++) {
if (!(SH_I2C_ICCR2_BBSY & readb(&base->iccr2)))
return 0;
udelay(10);
}
return 1;
}
static int check_ackbr(struct sh_i2c *base)
{
int i;
for (i = 0 ; i < IRQ_WAIT ; i++) {
if (!(SH_I2C_ICIER_ACKBR & readb(&base->icier)))
return 0;
udelay(10);
}
return 1;
}
static void sh_i2c_reset(struct sh_i2c *base)
{
setbits_8(&base->iccr2, SH_I2C_ICCR2_IICRST);
udelay(100);
clrbits_8(&base->iccr2, SH_I2C_ICCR2_IICRST);
}
static int i2c_set_addr(struct sh_i2c *base, u8 id, u8 reg)
{
if (check_bbsy(base)) {
puts("i2c bus busy\n");
goto fail;
}
setbits_8(&base->iccr1, SH_I2C_ICCR1_MTRS);
clrsetbits_8(&base->iccr2, SH_I2C_ICCR2_SCP, SH_I2C_ICCR2_BBSY);
writeb((id << 1), &base->icdrt);
if (check_tend(base, 0)) {
puts("TEND check fail...\n");
goto fail;
}
if (check_ackbr(base)) {
check_tend(base, 0);
sh_i2c_send_stop(base);
goto fail;
}
writeb(reg, &base->icdrt);
if (check_tdre(base)) {
puts("TDRE check fail...\n");
goto fail;
}
if (check_tend(base, 0)) {
puts("TEND check fail...\n");
goto fail;
}
return 0;
fail:
return 1;
}
static int
i2c_raw_write(struct sh_i2c *base, u8 id, u8 reg, u8 *val, int size)
{
int i;
if (i2c_set_addr(base, id, reg)) {
puts("Fail set slave address\n");
return 1;
}
for (i = 0; i < size; i++) {
writeb(val[i], &base->icdrt);
check_tdre(base);
}
check_tend(base, 1);
check_stop(base);
udelay(100);
clrbits_8(&base->iccr1, SH_I2C_ICCR1_MTRS);
clrbits_8(&base->icsr, SH_I2C_ICSR_TDRE);
sh_i2c_reset(base);
return 0;
}
static u8 i2c_raw_read(struct sh_i2c *base, u8 id, u8 reg)
{
u8 ret = 0;
if (i2c_set_addr(base, id, reg)) {
puts("Fail set slave address\n");
goto fail;
}
clrsetbits_8(&base->iccr2, SH_I2C_ICCR2_SCP, SH_I2C_ICCR2_BBSY);
writeb((id << 1) | 1, &base->icdrt);
if (check_tend(base, 0))
puts("TDRE check fail...\n");
clrsetbits_8(&base->iccr1, SH_I2C_ICCR1_TRS, SH_I2C_ICCR1_MST);
clrbits_8(&base->icsr, SH_I2C_ICSR_TDRE);
setbits_8(&base->icier, SH_I2C_ICIER_ACKBT);
setbits_8(&base->iccr1, SH_I2C_ICCR1_RCVD);
/* read data (dummy) */
ret = readb(&base->icdrr);
if (check_rdrf(base)) {
puts("check RDRF error\n");
goto fail;
}
clrbits_8(&base->icsr, SH_I2C_ICSR_STOP);
udelay(1000);
sh_i2c_send_stop(base);
if (check_stop(base)) {
puts("check STOP error\n");
goto fail;
}
clrbits_8(&base->iccr1, SH_I2C_ICCR1_MTRS);
clrbits_8(&base->icsr, SH_I2C_ICSR_TDRE);
/* data read */
ret = readb(&base->icdrr);
fail:
clrbits_8(&base->iccr1, SH_I2C_ICCR1_RCVD);
return ret;
}
#ifdef CONFIG_I2C_MULTI_BUS
static unsigned int current_bus;
/**
* i2c_set_bus_num - change active I2C bus
* @bus: bus index, zero based
* @returns: 0 on success, non-0 on failure
*/
int i2c_set_bus_num(unsigned int bus)
{
switch (bus) {
case 0:
base = (void *)CONFIG_SH_I2C_BASE0;
break;
case 1:
base = (void *)CONFIG_SH_I2C_BASE1;
break;
default:
printf("Bad bus: %d\n", bus);
return -1;
}
current_bus = bus;
return 0;
}
/**
* i2c_get_bus_num - returns index of active I2C bus
*/
unsigned int i2c_get_bus_num(void)
{
return current_bus;
}
#endif
void i2c_init(int speed, int slaveaddr)
{
#ifdef CONFIG_I2C_MULTI_BUS
current_bus = 0;
#endif
base = (struct sh_i2c *)CONFIG_SH_I2C_BASE0;
if (speed == 400000)
iccr1_cks = 0x07;
else
iccr1_cks = 0x0F;
nf2cyc = 1;
/* Reset */
sh_i2c_reset(base);
/* ICE enable and set clock */
writeb(SH_I2C_ICCR1_ICE | iccr1_cks, &base->iccr1);
writeb(nf2cyc, &base->nf2cyc);
}
/*
* i2c_read: - Read multiple bytes from an i2c device
*
* The higher level routines take into account that this function is only
* called with len < page length of the device (see configuration file)
*
* @chip: address of the chip which is to be read
* @addr: i2c data address within the chip
* @alen: length of the i2c data address (1..2 bytes)
* @buffer: where to write the data
* @len: how much byte do we want to read
* @return: 0 in case of success
*/
int i2c_read(u8 chip, u32 addr, int alen, u8 *buffer, int len)
{
int i = 0;
for (i = 0; i < len; i++)
buffer[i] = i2c_raw_read(base, chip, addr + i);
return 0;
}
/*
* i2c_write: - Write multiple bytes to an i2c device
*
* The higher level routines take into account that this function is only
* called with len < page length of the device (see configuration file)
*
* @chip: address of the chip which is to be written
* @addr: i2c data address within the chip
* @alen: length of the i2c data address (1..2 bytes)
* @buffer: where to find the data to be written
* @len: how much byte do we want to read
* @return: 0 in case of success
*/
int i2c_write(u8 chip, u32 addr, int alen, u8 *buffer, int len)
{
return i2c_raw_write(base, chip, addr, buffer, len);
}
/*
* i2c_probe: - Test if a chip answers for a given i2c address
*
* @chip: address of the chip which is searched for
* @return: 0 if a chip was found, -1 otherwhise
*/
int i2c_probe(u8 chip)
{
u8 byte;
return i2c_read(chip, 0, 0, &byte, 1);
}