diff options
Diffstat (limited to 'board/gth2/ee_access.c')
| -rw-r--r-- | board/gth2/ee_access.c | 347 |
1 files changed, 0 insertions, 347 deletions
diff --git a/board/gth2/ee_access.c b/board/gth2/ee_access.c deleted file mode 100644 index d4798c4..0000000 --- a/board/gth2/ee_access.c +++ /dev/null @@ -1,347 +0,0 @@ -/* 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); -} |