rockbox/firmware/target/arm/tms320dm320/i2c-dm320.c
Tomasz Moń 4539ffe1f3 TMS320DM320: Add generic I/O debug window for targets other than mrobe 500.
DEBUG_GIO allows users to set any GIO options (direction, output state). As this feature should be used only by experienced users it is compiled conditionally.

Raise I2C delay values since udelay() is now precise and previous values seems to be too low for some devices.


git-svn-id: svn://svn.rockbox.org/rockbox/trunk@31421 a1c6a512-1295-4272-9138-f99709370657
2011-12-24 14:18:53 +00:00

296 lines
7.4 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 "thread.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);
}
#endif