diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-sibyte.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-sibyte.c | 158 |
1 files changed, 155 insertions, 3 deletions
diff --git a/drivers/i2c/busses/i2c-sibyte.c b/drivers/i2c/busses/i2c-sibyte.c index fa503ed9f86..f516eb7a23f 100644 --- a/drivers/i2c/busses/i2c-sibyte.c +++ b/drivers/i2c/busses/i2c-sibyte.c @@ -1,6 +1,7 @@ /* * Copyright (C) 2004 Steven J. Hill * Copyright (C) 2001,2002,2003 Broadcom Corporation + * Copyright (C) 1995-2000 Simon G. Vogl * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License @@ -17,11 +18,162 @@ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ +#include <linux/kernel.h> #include <linux/module.h> -#include <linux/i2c-algo-sibyte.h> +#include <linux/init.h> +#include <linux/i2c.h> +#include <asm/io.h> #include <asm/sibyte/sb1250_regs.h> #include <asm/sibyte/sb1250_smbus.h> + +struct i2c_algo_sibyte_data { + void *data; /* private data */ + int bus; /* which bus */ + void *reg_base; /* CSR base */ +}; + +/* ----- global defines ----------------------------------------------- */ +#define SMB_CSR(a,r) ((long)(a->reg_base + r)) + +/* ----- global variables --------------------------------------------- */ + +/* module parameters: + */ +static int bit_scan; /* have a look at what's hanging 'round */ +module_param(bit_scan, int, 0); +MODULE_PARM_DESC(bit_scan, "Scan for active chips on the bus"); + + +static int smbus_xfer(struct i2c_adapter *i2c_adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, union i2c_smbus_data * data) +{ + struct i2c_algo_sibyte_data *adap = i2c_adap->algo_data; + int data_bytes = 0; + int error; + + while (csr_in32(SMB_CSR(adap, R_SMB_STATUS)) & M_SMB_BUSY) + ; + + switch (size) { + case I2C_SMBUS_QUICK: + csr_out32((V_SMB_ADDR(addr) | + (read_write == I2C_SMBUS_READ ? M_SMB_QDATA : 0) | + V_SMB_TT_QUICKCMD), SMB_CSR(adap, R_SMB_START)); + break; + case I2C_SMBUS_BYTE: + if (read_write == I2C_SMBUS_READ) { + csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_RD1BYTE), + SMB_CSR(adap, R_SMB_START)); + data_bytes = 1; + } else { + csr_out32(V_SMB_CMD(command), SMB_CSR(adap, R_SMB_CMD)); + csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_WR1BYTE), + SMB_CSR(adap, R_SMB_START)); + } + break; + case I2C_SMBUS_BYTE_DATA: + csr_out32(V_SMB_CMD(command), SMB_CSR(adap, R_SMB_CMD)); + if (read_write == I2C_SMBUS_READ) { + csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_CMD_RD1BYTE), + SMB_CSR(adap, R_SMB_START)); + data_bytes = 1; + } else { + csr_out32(V_SMB_LB(data->byte), + SMB_CSR(adap, R_SMB_DATA)); + csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_WR2BYTE), + SMB_CSR(adap, R_SMB_START)); + } + break; + case I2C_SMBUS_WORD_DATA: + csr_out32(V_SMB_CMD(command), SMB_CSR(adap, R_SMB_CMD)); + if (read_write == I2C_SMBUS_READ) { + csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_CMD_RD2BYTE), + SMB_CSR(adap, R_SMB_START)); + data_bytes = 2; + } else { + csr_out32(V_SMB_LB(data->word & 0xff), + SMB_CSR(adap, R_SMB_DATA)); + csr_out32(V_SMB_MB(data->word >> 8), + SMB_CSR(adap, R_SMB_DATA)); + csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_WR2BYTE), + SMB_CSR(adap, R_SMB_START)); + } + break; + default: + return -1; /* XXXKW better error code? */ + } + + while (csr_in32(SMB_CSR(adap, R_SMB_STATUS)) & M_SMB_BUSY) + ; + + error = csr_in32(SMB_CSR(adap, R_SMB_STATUS)); + if (error & M_SMB_ERROR) { + /* Clear error bit by writing a 1 */ + csr_out32(M_SMB_ERROR, SMB_CSR(adap, R_SMB_STATUS)); + return -1; /* XXXKW better error code? */ + } + + if (data_bytes == 1) + data->byte = csr_in32(SMB_CSR(adap, R_SMB_DATA)) & 0xff; + if (data_bytes == 2) + data->word = csr_in32(SMB_CSR(adap, R_SMB_DATA)) & 0xffff; + + return 0; +} + +static u32 bit_func(struct i2c_adapter *adap) +{ + return (I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA); +} + + +/* -----exported algorithm data: ------------------------------------- */ + +static struct i2c_algorithm i2c_sibyte_algo = { + .smbus_xfer = smbus_xfer, + .functionality = bit_func, +}; + +/* + * registering functions to load algorithms at runtime + */ +int i2c_sibyte_add_bus(struct i2c_adapter *i2c_adap, int speed) +{ + int i; + struct i2c_algo_sibyte_data *adap = i2c_adap->algo_data; + + /* register new adapter to i2c module... */ + i2c_adap->algo = &i2c_sibyte_algo; + + /* Set the frequency to 100 kHz */ + csr_out32(speed, SMB_CSR(adap,R_SMB_FREQ)); + csr_out32(0, SMB_CSR(adap,R_SMB_CONTROL)); + + /* scan bus */ + if (bit_scan) { + union i2c_smbus_data data; + int rc; + printk(KERN_INFO " i2c-algo-sibyte.o: scanning bus %s.\n", + i2c_adap->name); + for (i = 0x00; i < 0x7f; i++) { + /* XXXKW is this a realistic probe? */ + rc = smbus_xfer(i2c_adap, i, 0, I2C_SMBUS_READ, 0, + I2C_SMBUS_BYTE_DATA, &data); + if (!rc) { + printk("(%02x)",i); + } else + printk("."); + } + printk("\n"); + } + + return i2c_add_adapter(i2c_adap); +} + + static struct i2c_algo_sibyte_data sibyte_board_data[2] = { { NULL, 0, (void *) (CKSEG1+A_SMB_BASE(0)) }, { NULL, 1, (void *) (CKSEG1+A_SMB_BASE(1)) } @@ -58,8 +210,8 @@ static int __init i2c_sibyte_init(void) static void __exit i2c_sibyte_exit(void) { - i2c_sibyte_del_bus(&sibyte_board_adapter[0]); - i2c_sibyte_del_bus(&sibyte_board_adapter[1]); + i2c_del_bus(&sibyte_board_adapter[0]); + i2c_del_bus(&sibyte_board_adapter[1]); } module_init(i2c_sibyte_init); |