| /* ------------------------------------------------------------------------- */ |
| /* i2c-algo-sibyte.c i2c driver algorithms for bit-shift adapters */ |
| /* ------------------------------------------------------------------------- */ |
| /* 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 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., 675 Mass Ave, Cambridge, MA 02139, USA. */ |
| /* ------------------------------------------------------------------------- */ |
| |
| /* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and even |
| Frodo Looijaard <frodol@dds.nl>. */ |
| |
| /* Ported for SiByte SOCs by Broadcom Corporation. */ |
| |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/init.h> |
| |
| #include <asm/io.h> |
| #include <asm/sibyte/sb1250_regs.h> |
| #include <asm/sibyte/sb1250_smbus.h> |
| |
| #include <linux/i2c.h> |
| #include <linux/i2c-algo-sibyte.h> |
| |
| /* ----- 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 */ |
| |
| |
| 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 int algo_control(struct i2c_adapter *adapter, |
| unsigned int cmd, unsigned long arg) |
| { |
| 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, |
| .algo_control = algo_control, /* ioctl */ |
| .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"); |
| } |
| |
| i2c_add_adapter(i2c_adap); |
| |
| return 0; |
| } |
| |
| |
| int i2c_sibyte_del_bus(struct i2c_adapter *adap) |
| { |
| int res; |
| |
| if ((res = i2c_del_adapter(adap)) < 0) |
| return res; |
| |
| return 0; |
| } |
| |
| int __init i2c_algo_sibyte_init (void) |
| { |
| printk("i2c-algo-sibyte.o: i2c SiByte algorithm module\n"); |
| return 0; |
| } |
| |
| |
| EXPORT_SYMBOL(i2c_sibyte_add_bus); |
| EXPORT_SYMBOL(i2c_sibyte_del_bus); |
| |
| #ifdef MODULE |
| MODULE_AUTHOR("Kip Walker, Broadcom Corp."); |
| MODULE_DESCRIPTION("SiByte I2C-Bus algorithm"); |
| module_param(bit_scan, int, 0); |
| MODULE_PARM_DESC(bit_scan, "Scan for active chips on the bus"); |
| MODULE_LICENSE("GPL"); |
| |
| int init_module(void) |
| { |
| return i2c_algo_sibyte_init(); |
| } |
| |
| void cleanup_module(void) |
| { |
| } |
| #endif |
