mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-11-14 17:07:38 +00:00
b87dfd2854
The TB5200 ("Tinybox") is a small baseboard for the TQM5200 module
integrated in a little aluminium case.
Patch by Martin Krause, 8 Jun 2006
Some code cleanup
347 lines
7.5 KiB
C
347 lines
7.5 KiB
C
/* Module for handling DALLAS DS2438, smart battery monitor
|
|
Chip can store up to 40 bytes of user data in EEPROM,
|
|
perform temp, voltage and current measurements.
|
|
Chip also contains a unique serial number.
|
|
|
|
Always read/write LSb first
|
|
|
|
For documentaion, see data sheet for DS2438, 2438.pdf
|
|
|
|
By Thomas.Lange@corelatus.com 001025
|
|
|
|
Copyright (C) 2000-2005 Corelatus AB */
|
|
|
|
/* 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 <command.h>
|
|
#include <asm/au1x00.h>
|
|
#include <asm/io.h>
|
|
#include "ee_dev.h"
|
|
#include "ee_access.h"
|
|
|
|
/* static int Debug = 1; */
|
|
#undef E_DEBUG
|
|
#define E_DEBUG(fmt,args...) /* */
|
|
/* #define E_DEBUG(fmt,args...) printk("EEA:"fmt,##args); */
|
|
|
|
/* We dont have kernel functions */
|
|
#define printk printf
|
|
#define KERN_DEBUG
|
|
#define KERN_ERR
|
|
#define EIO 1
|
|
|
|
#ifndef TRUE
|
|
#define TRUE 1
|
|
#endif
|
|
#ifndef FALSE
|
|
#define FALSE 0
|
|
#endif
|
|
|
|
/* lookup table ripped from DS app note 17, understanding and using cyclic redundancy checks... */
|
|
|
|
static u8 crc_lookup[256] = {
|
|
0, 94, 188, 226, 97, 63, 221, 131,
|
|
194, 156, 126, 32, 163, 253, 31, 65,
|
|
157, 195, 33, 127, 252, 162, 64, 30,
|
|
95, 1, 227, 189, 62, 96, 130, 220,
|
|
35, 125, 159, 193, 66, 28, 254, 160,
|
|
225, 191, 93, 3, 128, 222, 60, 98,
|
|
190, 224, 2, 92, 223, 129, 99, 61,
|
|
124, 34, 192, 158, 29, 67, 161, 255,
|
|
70, 24, 250, 164, 39, 121, 155, 197,
|
|
132, 218, 56, 102, 229, 187, 89, 7,
|
|
219, 133, 103, 57, 186, 228, 6, 88,
|
|
25, 71, 165, 251, 120, 38, 196, 154,
|
|
101, 59, 217, 135, 4, 90, 184, 230,
|
|
167, 249, 27, 69, 198, 152, 122, 36,
|
|
248, 166, 68, 26, 153, 199, 37, 123,
|
|
58, 100, 134, 216, 91, 5, 231, 185,
|
|
140, 210, 48, 110, 237, 179, 81, 15,
|
|
78, 16, 242, 172, 47, 113, 147, 205,
|
|
17, 79, 173, 243, 112, 46, 204, 146,
|
|
211, 141, 111, 49, 178, 236, 14, 80,
|
|
175, 241, 19, 77, 206, 144, 114, 44,
|
|
109, 51, 209, 143, 12, 82, 176, 238,
|
|
50, 108, 142, 208, 83, 13, 239, 177,
|
|
240, 174, 76, 18, 145, 207, 45, 115,
|
|
202, 148, 118, 40, 171, 245, 23, 73,
|
|
8, 86, 180, 234, 105, 55, 213, 139,
|
|
87, 9, 235, 181, 54, 104, 138, 212,
|
|
149, 203, 41, 119, 244, 170, 72, 22,
|
|
233, 183, 85, 11, 136, 214, 52, 106,
|
|
43, 117, 151, 201, 74, 20, 246, 168,
|
|
116, 42, 200, 150, 21, 75, 169, 247,
|
|
182, 232, 10, 84, 215, 137, 107, 53
|
|
};
|
|
|
|
static void
|
|
write_gpio_data(int value ){
|
|
if(value){
|
|
/* Tristate */
|
|
gpio_tristate(GPIO_EEDQ);
|
|
}
|
|
else{
|
|
/* Drive 0 */
|
|
gpio_clear(GPIO_EEDQ);
|
|
}
|
|
}
|
|
|
|
static u8 make_new_crc( u8 Old_crc, u8 New_value ){
|
|
/* Compute a new checksum with new byte, using previous checksum as input
|
|
See DS app note 17, understanding and using cyclic redundancy checks...
|
|
Also see DS2438, page 11 */
|
|
return( crc_lookup[Old_crc ^ New_value ]);
|
|
}
|
|
|
|
int ee_crc_ok( u8 *Buffer, int Len, u8 Crc ){
|
|
/* Check if the checksum for this buffer is correct */
|
|
u8 Curr_crc=0;
|
|
int i;
|
|
u8 *Curr_byte = Buffer;
|
|
|
|
for(i=0;i<Len;i++){
|
|
Curr_crc = make_new_crc( Curr_crc, *Curr_byte);
|
|
Curr_byte++;
|
|
}
|
|
E_DEBUG("Calculated CRC = 0x%x, read = 0x%x\n", Curr_crc, Crc);
|
|
|
|
if(Curr_crc == Crc){
|
|
/* Good */
|
|
return(TRUE);
|
|
}
|
|
printk(KERN_ERR"EE checksum error, Calculated CRC = 0x%x, read = 0x%x\n", Curr_crc, Crc);
|
|
return(FALSE);
|
|
}
|
|
|
|
static void
|
|
set_idle(void){
|
|
/* Send idle and keep start time
|
|
Continous 1 is idle */
|
|
WRITE_PORT(1);
|
|
}
|
|
|
|
|
|
static int
|
|
do_cpu_reset(void){
|
|
/* Release reset and verify that chip responds with presence pulse */
|
|
int Retries=0;
|
|
while(Retries<15){
|
|
udelay(RESET_LOW_TIME);
|
|
|
|
/* Send reset */
|
|
WRITE_PORT(0);
|
|
udelay(RESET_LOW_TIME);
|
|
|
|
/* Release reset */
|
|
WRITE_PORT(1);
|
|
|
|
/* Wait for EEPROM to drive output */
|
|
udelay(PRESENCE_TIMEOUT);
|
|
if(!READ_PORT){
|
|
/* Ok, EEPROM is driving a 0 */
|
|
E_DEBUG("Presence detected\n");
|
|
if(Retries){
|
|
E_DEBUG("Retries %d\n",Retries);
|
|
}
|
|
/* Make sure chip releases pin */
|
|
udelay(PRESENCE_LOW_TIME);
|
|
return 0;
|
|
}
|
|
Retries++;
|
|
}
|
|
|
|
printk(KERN_ERR"eeprom did not respond when releasing reset\n");
|
|
|
|
/* Make sure chip releases pin */
|
|
udelay(PRESENCE_LOW_TIME);
|
|
|
|
/* Set to idle again */
|
|
set_idle();
|
|
|
|
return(-EIO);
|
|
}
|
|
|
|
static u8
|
|
read_cpu_byte(void){
|
|
/* Read a single byte from EEPROM
|
|
Read LSb first */
|
|
int i;
|
|
int Value;
|
|
u8 Result=0;
|
|
u32 Flags;
|
|
|
|
E_DEBUG("Reading byte\n");
|
|
|
|
for(i=0;i<8;i++){
|
|
/* Small delay between pulses */
|
|
udelay(1);
|
|
|
|
#ifdef __KERNEL__
|
|
/* Disable irq */
|
|
save_flags(Flags);
|
|
cli();
|
|
#endif
|
|
|
|
/* Pull down pin short time to start read
|
|
See page 26 in data sheet */
|
|
|
|
WRITE_PORT(0);
|
|
udelay(READ_LOW);
|
|
WRITE_PORT(1);
|
|
|
|
/* Wait for chip to drive pin */
|
|
udelay(READ_TIMEOUT);
|
|
|
|
Value = READ_PORT;
|
|
if(Value)
|
|
Value=1;
|
|
|
|
#ifdef __KERNEL__
|
|
/* Enable irq */
|
|
restore_flags(Flags);
|
|
#endif
|
|
|
|
/* Wait for chip to release pin */
|
|
udelay(TOTAL_READ_LOW-READ_TIMEOUT);
|
|
|
|
/* LSb first */
|
|
Result|=Value<<i;
|
|
/* E_DEBUG("Read %d\n",Value); */
|
|
|
|
}
|
|
|
|
E_DEBUG("Read byte 0x%x\n",Result);
|
|
|
|
return(Result);
|
|
}
|
|
|
|
static void
|
|
write_cpu_byte(u8 Byte){
|
|
/* Write a single byte to EEPROM
|
|
Write LSb first */
|
|
int i;
|
|
int Value;
|
|
u32 Flags;
|
|
|
|
E_DEBUG("Writing byte 0x%x\n",Byte);
|
|
|
|
for(i=0;i<8;i++){
|
|
/* Small delay between pulses */
|
|
udelay(1);
|
|
Value = Byte&1;
|
|
|
|
#ifdef __KERNEL__
|
|
/* Disable irq */
|
|
save_flags(Flags);
|
|
cli();
|
|
#endif
|
|
|
|
/* Pull down pin short time for a 1, long time for a 0
|
|
See page 26 in data sheet */
|
|
|
|
WRITE_PORT(0);
|
|
if(Value){
|
|
/* Write a 1 */
|
|
udelay(WRITE_1_LOW);
|
|
}
|
|
else{
|
|
/* Write a 0 */
|
|
udelay(WRITE_0_LOW);
|
|
}
|
|
|
|
WRITE_PORT(1);
|
|
|
|
#ifdef __KERNEL__
|
|
/* Enable irq */
|
|
restore_flags(Flags);
|
|
#endif
|
|
|
|
if(Value)
|
|
/* Wait for chip to read the 1 */
|
|
udelay(TOTAL_WRITE_LOW-WRITE_1_LOW);
|
|
|
|
/* E_DEBUG("Wrote %d\n",Value); */
|
|
Byte>>=1;
|
|
}
|
|
}
|
|
|
|
int ee_do_cpu_command( u8 *Tx, int Tx_len, u8 *Rx, int Rx_len, int Send_skip ){
|
|
/* Execute this command string, including
|
|
giving reset and setting to idle after command
|
|
if Rx_len is set, we read out data from EEPROM */
|
|
int i;
|
|
|
|
E_DEBUG("Command, Tx_len %d, Rx_len %d\n", Tx_len, Rx_len );
|
|
|
|
if(do_cpu_reset()){
|
|
/* Failed! */
|
|
return(-EIO);
|
|
}
|
|
|
|
if(Send_skip)
|
|
/* Always send SKIP_ROM first to tell chip we are sending a command,
|
|
except when we read out rom data for chip */
|
|
write_cpu_byte(SKIP_ROM);
|
|
|
|
/* Always have Tx data */
|
|
for(i=0;i<Tx_len;i++){
|
|
write_cpu_byte(Tx[i]);
|
|
}
|
|
|
|
if(Rx_len){
|
|
for(i=0;i<Rx_len;i++){
|
|
Rx[i]=read_cpu_byte();
|
|
}
|
|
}
|
|
|
|
set_idle();
|
|
|
|
E_DEBUG("Command done\n");
|
|
|
|
return(0);
|
|
}
|
|
|
|
int ee_init_cpu_data(void){
|
|
int i;
|
|
u8 Tx[10];
|
|
|
|
/* Leave it floting since altera is driving the same pin */
|
|
set_idle();
|
|
|
|
/* Copy all User EEPROM data to scratchpad */
|
|
for(i=0;i<USER_PAGES;i++){
|
|
Tx[0]=RECALL_MEMORY;
|
|
Tx[1]=EE_USER_PAGE_0+i;
|
|
if(ee_do_cpu_command(Tx,2,NULL,0,TRUE)) return(-EIO);
|
|
}
|
|
|
|
/* Make sure chip doesnt store measurements in NVRAM */
|
|
Tx[0]=WRITE_SCRATCHPAD;
|
|
Tx[1]=0; /* Page */
|
|
Tx[2]=9;
|
|
if(ee_do_cpu_command(Tx,3,NULL,0,TRUE)) return(-EIO);
|
|
|
|
Tx[0]=COPY_SCRATCHPAD;
|
|
if(ee_do_cpu_command(Tx,2,NULL,0,TRUE)) return(-EIO);
|
|
|
|
for(i=0;i<10;i++){
|
|
udelay(1000);
|
|
}
|
|
|
|
return(0);
|
|
}
|