rockbox/firmware/target/arm/tms320dm320/i2c-dm320.c
Tomasz Moń b4ecd612f7
Sansa Connect: Use deviceid in USB Serial Number
Atmel AT88SC6416C CryptoMemory is almost I2C compatible. The device
is connected to bitbanged I2C bus shared with compliant I2C devices.

Change-Id: Iec54702db1bdfb93c01291eef18ec60391c63b16
2021-07-10 08:56:32 +02:00

305 lines
7.7 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2011 by Tomasz Moń
* Copyright (C) 2008 by Maurus Cuelenaere
*
* DM320 I²C driver
*
* 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "system.h"
#include "kernel.h"
#include "i2c-dm320.h"
#ifdef HAVE_SOFTWARE_I2C
#include "generic_i2c.h"
#endif
#ifndef HAVE_SOFTWARE_I2C
static struct mutex i2c_mtx;
static inline void i2c_begin(void)
{
mutex_lock(&i2c_mtx);
}
static inline void i2c_end(void)
{
mutex_unlock(&i2c_mtx);
}
#define I2C_SCS_COND_START 0x0001
#define I2C_SCS_COND_STOP 0x0002
#define I2C_SCS_XMIT 0x0004
#define I2C_TX_ACK (1 << 8)
static inline bool i2c_getack(void)
{
return (IO_I2C_RXDATA >> 8) & 1;
}
static inline void i2c_ack(void)
{
IO_I2C_TXDATA |= I2C_TX_ACK;
}
#define WAIT_FOR_I2C if(IO_I2C_SCS & 0x4){ \
while(IO_I2C_SCS & 0x4) { \
asm volatile("nop"); \
} \
} \
static inline void i2c_start(void)
{
IO_I2C_SCS |= I2C_SCS_XMIT;
return;
}
int i2c_write(unsigned short address, const unsigned char *buf, int count)
{
int i;
int ret=0;
i2c_begin();
IO_I2C_TXDATA = ( (address << 1) & 0xFF ) | (address>0x7F ? 0 : 1 ) | I2C_TX_ACK;
IO_I2C_SCS &= ~0x3; //clear conditions
IO_I2C_SCS |= I2C_SCS_COND_START; // write 'start condition'
i2c_start();
WAIT_FOR_I2C;
/* experimental */
if(address>0x7F){ // check if it is 10-bit instead of 7-bit
IO_I2C_TXDATA = ( (address >> 7) & 0xFF) | I2C_TX_ACK;
IO_I2C_SCS &= ~0x3; //normal transfer
i2c_start();
WAIT_FOR_I2C;
IO_I2C_TXDATA = ( (address << 1) & 0xFF) | 1 | I2C_TX_ACK;
IO_I2C_SCS &= ~0x3; //clear conditions
IO_I2C_SCS |= I2C_SCS_COND_START; //write 'start condition'
i2c_start();
WAIT_FOR_I2C;
}
for(i=0; i<count; i++){
IO_I2C_TXDATA = buf[i] | I2C_TX_ACK;
IO_I2C_SCS &= ~0x3; //normal transfer
i2c_start();
WAIT_FOR_I2C;
if(!i2c_getack())
ret = -1;
}
IO_I2C_SCS &= ~0x3; //clear conditions
IO_I2C_SCS |= I2C_SCS_COND_STOP; //write 'stop condition'
i2c_start();
WAIT_FOR_I2C;
i2c_end();
return ret;
}
int i2c_read(unsigned short address, unsigned char* buf, int count)
{
int i;
int ack=0;
i2c_begin();
IO_I2C_TXDATA = ( (address << 1) & 0xFF ) | (address>0x7F ? 0 : 1 ) | I2C_TX_ACK;
IO_I2C_SCS &= ~0x3; //clear conditions
IO_I2C_SCS |= I2C_SCS_COND_START; // write 'start condition'
i2c_start();
WAIT_FOR_I2C;
/* experimental */
if(address>0x7F){ // check if it is 10-bit instead of 7-bit
IO_I2C_TXDATA = ( (address >> 7) & 0xFF ) | I2C_TX_ACK;
IO_I2C_SCS &= ~0x3; //normal transfer
i2c_start();
WAIT_FOR_I2C;
IO_I2C_TXDATA = ( (address << 1) & 0xFF ) | 1 | I2C_TX_ACK;
IO_I2C_SCS &= ~0x3; //clear conditions
IO_I2C_SCS |= I2C_SCS_COND_START; //write 'start condition'
i2c_start();
WAIT_FOR_I2C;
}
for(i=0; i<count; i++){
unsigned short temp;
IO_I2C_TXDATA = 0xFF | ( (count-1)==i ? I2C_TX_ACK : 0);
IO_I2C_SCS &= ~0x3; //normal transfer
i2c_start();
WAIT_FOR_I2C;
temp = IO_I2C_RXDATA;
buf[i] = temp & 0xFF;
ack = (temp & 0x100) >> 8;
}
IO_I2C_SCS &= ~0x3; //clear conditions
IO_I2C_SCS |= I2C_SCS_COND_STOP; //write 'stop condition'
i2c_start();
WAIT_FOR_I2C;
i2c_end();
return ack;
}
void i2c_init(void)
{
mutex_init(&i2c_mtx);
#ifdef CREATIVE_ZVx //TODO: mimic OF I2C clock settings; currently this is done by the bootloader
IO_CLK_MOD2 &= ~CLK_MOD2_I2C; // turn I²C clock off (just to be sure)
IO_CLK_LPCTL1 &= ~1; // set Powerdown mode to off
IO_CLK_SEL0 &= ~0x800; // set I²C clock to PLLA
IO_CLK_DIV4 &= ~0x1F; // I²C clock division = 1
IO_CLK_MOD2 |= CLK_MOD2_I2C; // enable I²C clock
#endif
IO_I2C_SCS &= ~0x8; //set clock to 100 kHz
IO_INTC_EINT2 &= ~INTR_EINT2_I2C; // disable I²C interrupt
}
#else /* Software I2C implementation */
#ifdef SANSA_CONNECT
/* SDA - GIO35 */
#define SDA_SET_REG IO_GIO_BITSET2
#define SDA_CLR_REG IO_GIO_BITCLR2
#define SOFTI2C_SDA (1 << 3)
/* SCL - GIO36 */
#define SCL_SET_REG IO_GIO_BITSET2
#define SCL_CLR_REG IO_GIO_BITCLR2
#define SOFTI2C_SCL (1 << 4)
#else
#error Configure SDA and SCL lines
#endif
static int dm320_i2c_bus;
static void dm320_scl_dir(bool out)
{
if (out)
{
IO_GIO_DIR2 &= ~(SOFTI2C_SCL);
}
else
{
IO_GIO_DIR2 |= SOFTI2C_SCL;
}
}
static void dm320_sda_dir(bool out)
{
if (out)
{
IO_GIO_DIR2 &= ~(SOFTI2C_SDA);
}
else
{
IO_GIO_DIR2 |= SOFTI2C_SDA;
}
}
static void dm320_scl_out(bool high)
{
if (high)
{
SCL_SET_REG = SOFTI2C_SCL;
}
else
{
SCL_CLR_REG = SOFTI2C_SCL;
}
}
static void dm320_sda_out(bool high)
{
if (high)
{
SDA_SET_REG = SOFTI2C_SDA;
}
else
{
SDA_CLR_REG = SOFTI2C_SDA;
}
}
static bool dm320_scl_in(void)
{
return (SCL_SET_REG & SOFTI2C_SCL);
}
static bool dm320_sda_in(void)
{
return (SDA_SET_REG & SOFTI2C_SDA);
}
/* simple delay */
static void dm320_i2c_delay(int delay)
{
udelay(delay);
}
/* interface towards the generic i2c driver */
static const struct i2c_interface dm320_i2c_interface = {
.scl_dir = dm320_scl_dir,
.sda_dir = dm320_sda_dir,
.scl_out = dm320_scl_out,
.sda_out = dm320_sda_out,
.scl_in = dm320_scl_in,
.sda_in = dm320_sda_in,
.delay = dm320_i2c_delay,
/* uncalibrated */
.delay_hd_sta = 2,
.delay_hd_dat = 2,
.delay_su_dat = 2,
.delay_su_sto = 2,
.delay_su_sta = 2,
.delay_thigh = 2
};
void i2c_init(void)
{
#ifdef SANSA_CONNECT
IO_GIO_FSEL3 &= 0xFF0F; /* GIO35, GIO36 as normal GIO */
IO_GIO_INV2 &= ~(SOFTI2C_SDA | SOFTI2C_SCL); /* not inverted */
#endif
/* generic_i2c takes care of setting direction */
dm320_i2c_bus = i2c_add_node(&dm320_i2c_interface);
}
int i2c_write(unsigned short address, const unsigned char* buf, int count)
{
return i2c_write_data(dm320_i2c_bus, address, -1, buf, count);
}
int i2c_read(unsigned short address, unsigned char* buf, int count)
{
return i2c_read_data(dm320_i2c_bus, address, -1, buf, count);
}
int i2c_read_bytes(unsigned short address, unsigned short reg,
unsigned char* buf, int count)
{
return i2c_read_data(dm320_i2c_bus, address, reg, buf, count);
}
int i2c_write_read_bytes(unsigned short address,
const unsigned char* buf_write, int count_write,
unsigned char* buf_read, int count_read)
{
return i2c_write_read_data(dm320_i2c_bus, address, buf_write, count_write,
buf_read, count_read);
}
#endif