/* ------------------------------------------------------------------------- */ /* 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 and even Frodo Looijaard . */ /* Ported for SiByte SOCs by Broadcom Corporation. */ #include #include #include #include #include #include #include #include /* ----- 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