diff options
Diffstat (limited to 'arch/arm/plat-aspeed/i2c-slave-eeprom.c')
| -rw-r--r-- | arch/arm/plat-aspeed/i2c-slave-eeprom.c | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/arch/arm/plat-aspeed/i2c-slave-eeprom.c b/arch/arm/plat-aspeed/i2c-slave-eeprom.c new file mode 100644 index 0000000..fd53f1a --- /dev/null +++ b/arch/arm/plat-aspeed/i2c-slave-eeprom.c @@ -0,0 +1,141 @@ +/******************************************************************************** +* File Name : linux/arch/arm/plat-aspeed/i2c-slave-eeprom.c +* Author : Ryan chen +* Description : ASPEED I2C Device +* +* Copyright (C) ASPEED Technology Inc. +* 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 + +* History : +* 1. 2013/05/30 ryan chen create this file +* +********************************************************************************/ +#include <linux/i2c.h> +#if defined(CONFIG_COLDFIRE) +#include <asm/arch/ast_i2c.h> +#else +#include <plat/ast_i2c.h> +#endif + +#ifdef I2C_EEPROM +#define EEPROM_DBUG(fmt, args...) printk("%s() " fmt, __FUNCTION__, ## args) +#else +#define EEPROM_DBUG(fmt, args...) +#endif + +static u8 cmd_buf[1] = {0}; +static struct i2c_msg cmd_msg = { + .addr = 0x04, + .len = 1, + .buf = cmd_buf, +}; + +//Note 10 byte data memory share for all bus slave device ........... +#define BUF_SIZE 10 + +static u8 store_memory[BUF_SIZE] = {0x03,0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09}; + // RO, RW, ................. +static struct i2c_msg data_msg = { + .addr = 0x04, + .len = BUF_SIZE, + .buf = store_memory, +}; +static u8 mem_index = 0; +static u8 slave_stage = INIT_STAGE; + +extern void i2c_slave_init(struct i2c_msg **msgs) +{ + *msgs = &cmd_msg; +} + +extern void i2c_slave_xfer(i2c_slave_event_t event, struct i2c_msg **msgs) +{ + EEPROM_DBUG("[event %d] \n",event); + switch(event) { + case I2C_SLAVE_EVENT_START_READ: + cmd_msg.flags = I2C_M_RD; + data_msg.flags = I2C_M_RD; + if(slave_stage == INIT_STAGE) { + EEPROM_DBUG("Rt DATA_MSG [%x]\n",data_msg.buf[0]); + slave_stage = DATA_STAGE; + *msgs = &data_msg; + } else { + //CMD_STAGE + if(cmd_msg.buf[0] != ((cmd_msg.addr << 1)|1)) + printk("START READ ADDR Error %x\n",cmd_msg.buf[0]); + + EEPROM_DBUG("Rt CMD_DATA_MSG data [%x]\n",store_memory[mem_index]); + cmd_msg.buf[0] = store_memory[mem_index]; + mem_index++; + mem_index %=BUF_SIZE; + slave_stage = CMD_DATA_STAGE; + *msgs = &cmd_msg; + } + break; + case I2C_SLAVE_EVENT_START_WRITE: + EEPROM_DBUG("Rt CMD_MSG START_WRITE %x\n",cmd_msg.buf[0]); + cmd_msg.flags = 0; + if(cmd_msg.buf[0] != cmd_msg.addr <<1) + printk("ERROR ADDRESS Match [%x] \n", cmd_msg.buf[0]); + slave_stage = CMD_STAGE; + + *msgs = &cmd_msg; + + break; + + case I2C_SLAVE_EVENT_WRITE: + cmd_msg.flags = 0; + if(slave_stage == CMD_STAGE) { + EEPROM_DBUG("w CMD = [index %x] \n",cmd_msg.buf[0]); + mem_index = cmd_msg.buf[0]; + mem_index %= BUF_SIZE; + slave_stage = CMD_DATA_STAGE; + *msgs = &cmd_msg; + } else { + EEPROM_DBUG("w index %d CMD_DATA [%x] \n",mem_index, cmd_msg.buf[0]); + if(mem_index !=0) + store_memory[mem_index] = cmd_msg.buf[0]; + mem_index++; + mem_index %=BUF_SIZE; + EEPROM_DBUG("Rt CMD_DATA_MSG \n"); + *msgs = &cmd_msg; + } + break; + case I2C_SLAVE_EVENT_READ: + cmd_msg.flags = I2C_M_RD; + if(slave_stage == CMD_DATA_STAGE) { + cmd_msg.buf[0] = store_memory[mem_index]; + mem_index++; + mem_index %=BUF_SIZE; + EEPROM_DBUG("Rt CMD_DATA_MSG [%x]\n",cmd_msg.buf[0]); + *msgs = &cmd_msg; + } else { + EEPROM_DBUG("Rt DATA_MSG [%x]\n",data_msg.buf[0]); + *msgs = &data_msg; + } + break; + case I2C_SLAVE_EVENT_NACK: + cmd_msg.flags = I2C_M_RD; + slave_stage = INIT_STAGE; + *msgs = &cmd_msg; + + break; + + case I2C_SLAVE_EVENT_STOP: + cmd_msg.flags = I2C_M_RD; + slave_stage = INIT_STAGE; + *msgs = &cmd_msg; + break; + } + +} |
