1 /* 2 * Copyright (C) 2004 Steven J. Hill 3 * Copyright (C) 2001,2002,2003 Broadcom Corporation 4 * Copyright (C) 1995-2000 Simon G. Vogl 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 2 9 * of the License, or (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 19 */ 20 21 #include <linux/kernel.h> 22 #include <linux/module.h> 23 #include <linux/init.h> 24 #include <linux/i2c.h> 25 #include <linux/io.h> 26 #include <asm/sibyte/sb1250_regs.h> 27 #include <asm/sibyte/sb1250_smbus.h> 28 29 30 struct i2c_algo_sibyte_data { 31 void *data; /* private data */ 32 int bus; /* which bus */ 33 void *reg_base; /* CSR base */ 34 }; 35 36 /* ----- global defines ----------------------------------------------- */ 37 #define SMB_CSR(a,r) ((long)(a->reg_base + r)) 38 39 40 static int smbus_xfer(struct i2c_adapter *i2c_adap, u16 addr, 41 unsigned short flags, char read_write, 42 u8 command, int size, union i2c_smbus_data * data) 43 { 44 struct i2c_algo_sibyte_data *adap = i2c_adap->algo_data; 45 int data_bytes = 0; 46 int error; 47 48 while (csr_in32(SMB_CSR(adap, R_SMB_STATUS)) & M_SMB_BUSY) 49 ; 50 51 switch (size) { 52 case I2C_SMBUS_QUICK: 53 csr_out32((V_SMB_ADDR(addr) | 54 (read_write == I2C_SMBUS_READ ? M_SMB_QDATA : 0) | 55 V_SMB_TT_QUICKCMD), SMB_CSR(adap, R_SMB_START)); 56 break; 57 case I2C_SMBUS_BYTE: 58 if (read_write == I2C_SMBUS_READ) { 59 csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_RD1BYTE), 60 SMB_CSR(adap, R_SMB_START)); 61 data_bytes = 1; 62 } else { 63 csr_out32(V_SMB_CMD(command), SMB_CSR(adap, R_SMB_CMD)); 64 csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_WR1BYTE), 65 SMB_CSR(adap, R_SMB_START)); 66 } 67 break; 68 case I2C_SMBUS_BYTE_DATA: 69 csr_out32(V_SMB_CMD(command), SMB_CSR(adap, R_SMB_CMD)); 70 if (read_write == I2C_SMBUS_READ) { 71 csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_CMD_RD1BYTE), 72 SMB_CSR(adap, R_SMB_START)); 73 data_bytes = 1; 74 } else { 75 csr_out32(V_SMB_LB(data->byte), 76 SMB_CSR(adap, R_SMB_DATA)); 77 csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_WR2BYTE), 78 SMB_CSR(adap, R_SMB_START)); 79 } 80 break; 81 case I2C_SMBUS_WORD_DATA: 82 csr_out32(V_SMB_CMD(command), SMB_CSR(adap, R_SMB_CMD)); 83 if (read_write == I2C_SMBUS_READ) { 84 csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_CMD_RD2BYTE), 85 SMB_CSR(adap, R_SMB_START)); 86 data_bytes = 2; 87 } else { 88 csr_out32(V_SMB_LB(data->word & 0xff), 89 SMB_CSR(adap, R_SMB_DATA)); 90 csr_out32(V_SMB_MB(data->word >> 8), 91 SMB_CSR(adap, R_SMB_DATA)); 92 csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_WR2BYTE), 93 SMB_CSR(adap, R_SMB_START)); 94 } 95 break; 96 default: 97 return -EOPNOTSUPP; 98 } 99 100 while (csr_in32(SMB_CSR(adap, R_SMB_STATUS)) & M_SMB_BUSY) 101 ; 102 103 error = csr_in32(SMB_CSR(adap, R_SMB_STATUS)); 104 if (error & M_SMB_ERROR) { 105 /* Clear error bit by writing a 1 */ 106 csr_out32(M_SMB_ERROR, SMB_CSR(adap, R_SMB_STATUS)); 107 return (error & M_SMB_ERROR_TYPE) ? -EIO : -ENXIO; 108 } 109 110 if (data_bytes == 1) 111 data->byte = csr_in32(SMB_CSR(adap, R_SMB_DATA)) & 0xff; 112 if (data_bytes == 2) 113 data->word = csr_in32(SMB_CSR(adap, R_SMB_DATA)) & 0xffff; 114 115 return 0; 116 } 117 118 static u32 bit_func(struct i2c_adapter *adap) 119 { 120 return (I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | 121 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA); 122 } 123 124 125 /* -----exported algorithm data: ------------------------------------- */ 126 127 static const struct i2c_algorithm i2c_sibyte_algo = { 128 .smbus_xfer = smbus_xfer, 129 .functionality = bit_func, 130 }; 131 132 /* 133 * registering functions to load algorithms at runtime 134 */ 135 static int __init i2c_sibyte_add_bus(struct i2c_adapter *i2c_adap, int speed) 136 { 137 struct i2c_algo_sibyte_data *adap = i2c_adap->algo_data; 138 139 /* Register new adapter to i2c module... */ 140 i2c_adap->algo = &i2c_sibyte_algo; 141 142 /* Set the requested frequency. */ 143 csr_out32(speed, SMB_CSR(adap,R_SMB_FREQ)); 144 csr_out32(0, SMB_CSR(adap,R_SMB_CONTROL)); 145 146 return i2c_add_numbered_adapter(i2c_adap); 147 } 148 149 150 static struct i2c_algo_sibyte_data sibyte_board_data[2] = { 151 { NULL, 0, (void *) (CKSEG1+A_SMB_BASE(0)) }, 152 { NULL, 1, (void *) (CKSEG1+A_SMB_BASE(1)) } 153 }; 154 155 static struct i2c_adapter sibyte_board_adapter[2] = { 156 { 157 .owner = THIS_MODULE, 158 .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, 159 .algo = NULL, 160 .algo_data = &sibyte_board_data[0], 161 .nr = 0, 162 .name = "SiByte SMBus 0", 163 }, 164 { 165 .owner = THIS_MODULE, 166 .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, 167 .algo = NULL, 168 .algo_data = &sibyte_board_data[1], 169 .nr = 1, 170 .name = "SiByte SMBus 1", 171 }, 172 }; 173 174 static int __init i2c_sibyte_init(void) 175 { 176 pr_info("i2c-sibyte: i2c SMBus adapter module for SiByte board\n"); 177 if (i2c_sibyte_add_bus(&sibyte_board_adapter[0], K_SMB_FREQ_100KHZ) < 0) 178 return -ENODEV; 179 if (i2c_sibyte_add_bus(&sibyte_board_adapter[1], 180 K_SMB_FREQ_400KHZ) < 0) { 181 i2c_del_adapter(&sibyte_board_adapter[0]); 182 return -ENODEV; 183 } 184 return 0; 185 } 186 187 static void __exit i2c_sibyte_exit(void) 188 { 189 i2c_del_adapter(&sibyte_board_adapter[0]); 190 i2c_del_adapter(&sibyte_board_adapter[1]); 191 } 192 193 module_init(i2c_sibyte_init); 194 module_exit(i2c_sibyte_exit); 195 196 MODULE_AUTHOR("Kip Walker (Broadcom Corp.), Steven J. Hill <sjhill@realitydiluted.com>"); 197 MODULE_DESCRIPTION("SMBus adapter routines for SiByte boards"); 198 MODULE_LICENSE("GPL"); 199