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8#include <linux/kernel.h>
9#include <linux/module.h>
10#include <linux/init.h>
11#include <linux/i2c.h>
12#include <linux/io.h>
13#include <asm/sibyte/sb1250_regs.h>
14#include <asm/sibyte/sb1250_smbus.h>
15
16
17struct i2c_algo_sibyte_data {
18 void *data;
19 int bus;
20 void *reg_base;
21};
22
23
24#define SMB_CSR(a,r) ((long)(a->reg_base + r))
25
26
27static int smbus_xfer(struct i2c_adapter *i2c_adap, u16 addr,
28 unsigned short flags, char read_write,
29 u8 command, int size, union i2c_smbus_data * data)
30{
31 struct i2c_algo_sibyte_data *adap = i2c_adap->algo_data;
32 int data_bytes = 0;
33 int error;
34
35 while (csr_in32(SMB_CSR(adap, R_SMB_STATUS)) & M_SMB_BUSY)
36 ;
37
38 switch (size) {
39 case I2C_SMBUS_QUICK:
40 csr_out32((V_SMB_ADDR(addr) |
41 (read_write == I2C_SMBUS_READ ? M_SMB_QDATA : 0) |
42 V_SMB_TT_QUICKCMD), SMB_CSR(adap, R_SMB_START));
43 break;
44 case I2C_SMBUS_BYTE:
45 if (read_write == I2C_SMBUS_READ) {
46 csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_RD1BYTE),
47 SMB_CSR(adap, R_SMB_START));
48 data_bytes = 1;
49 } else {
50 csr_out32(V_SMB_CMD(command), SMB_CSR(adap, R_SMB_CMD));
51 csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_WR1BYTE),
52 SMB_CSR(adap, R_SMB_START));
53 }
54 break;
55 case I2C_SMBUS_BYTE_DATA:
56 csr_out32(V_SMB_CMD(command), SMB_CSR(adap, R_SMB_CMD));
57 if (read_write == I2C_SMBUS_READ) {
58 csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_CMD_RD1BYTE),
59 SMB_CSR(adap, R_SMB_START));
60 data_bytes = 1;
61 } else {
62 csr_out32(V_SMB_LB(data->byte),
63 SMB_CSR(adap, R_SMB_DATA));
64 csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_WR2BYTE),
65 SMB_CSR(adap, R_SMB_START));
66 }
67 break;
68 case I2C_SMBUS_WORD_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_RD2BYTE),
72 SMB_CSR(adap, R_SMB_START));
73 data_bytes = 2;
74 } else {
75 csr_out32(V_SMB_LB(data->word & 0xff),
76 SMB_CSR(adap, R_SMB_DATA));
77 csr_out32(V_SMB_MB(data->word >> 8),
78 SMB_CSR(adap, R_SMB_DATA));
79 csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_WR2BYTE),
80 SMB_CSR(adap, R_SMB_START));
81 }
82 break;
83 default:
84 return -EOPNOTSUPP;
85 }
86
87 while (csr_in32(SMB_CSR(adap, R_SMB_STATUS)) & M_SMB_BUSY)
88 ;
89
90 error = csr_in32(SMB_CSR(adap, R_SMB_STATUS));
91 if (error & M_SMB_ERROR) {
92
93 csr_out32(M_SMB_ERROR, SMB_CSR(adap, R_SMB_STATUS));
94 return (error & M_SMB_ERROR_TYPE) ? -EIO : -ENXIO;
95 }
96
97 if (data_bytes == 1)
98 data->byte = csr_in32(SMB_CSR(adap, R_SMB_DATA)) & 0xff;
99 if (data_bytes == 2)
100 data->word = csr_in32(SMB_CSR(adap, R_SMB_DATA)) & 0xffff;
101
102 return 0;
103}
104
105static u32 bit_func(struct i2c_adapter *adap)
106{
107 return (I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
108 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA);
109}
110
111
112
113
114static const struct i2c_algorithm i2c_sibyte_algo = {
115 .smbus_xfer = smbus_xfer,
116 .functionality = bit_func,
117};
118
119
120
121
122static int __init i2c_sibyte_add_bus(struct i2c_adapter *i2c_adap, int speed)
123{
124 struct i2c_algo_sibyte_data *adap = i2c_adap->algo_data;
125
126
127 i2c_adap->algo = &i2c_sibyte_algo;
128
129
130 csr_out32(speed, SMB_CSR(adap,R_SMB_FREQ));
131 csr_out32(0, SMB_CSR(adap,R_SMB_CONTROL));
132
133 return i2c_add_numbered_adapter(i2c_adap);
134}
135
136
137static struct i2c_algo_sibyte_data sibyte_board_data[2] = {
138 { NULL, 0, (void *) (CKSEG1+A_SMB_BASE(0)) },
139 { NULL, 1, (void *) (CKSEG1+A_SMB_BASE(1)) }
140};
141
142static struct i2c_adapter sibyte_board_adapter[2] = {
143 {
144 .owner = THIS_MODULE,
145 .class = I2C_CLASS_HWMON | I2C_CLASS_SPD,
146 .algo = NULL,
147 .algo_data = &sibyte_board_data[0],
148 .nr = 0,
149 .name = "SiByte SMBus 0",
150 },
151 {
152 .owner = THIS_MODULE,
153 .class = I2C_CLASS_HWMON | I2C_CLASS_SPD,
154 .algo = NULL,
155 .algo_data = &sibyte_board_data[1],
156 .nr = 1,
157 .name = "SiByte SMBus 1",
158 },
159};
160
161static int __init i2c_sibyte_init(void)
162{
163 pr_info("i2c-sibyte: i2c SMBus adapter module for SiByte board\n");
164 if (i2c_sibyte_add_bus(&sibyte_board_adapter[0], K_SMB_FREQ_100KHZ) < 0)
165 return -ENODEV;
166 if (i2c_sibyte_add_bus(&sibyte_board_adapter[1],
167 K_SMB_FREQ_400KHZ) < 0) {
168 i2c_del_adapter(&sibyte_board_adapter[0]);
169 return -ENODEV;
170 }
171 return 0;
172}
173
174static void __exit i2c_sibyte_exit(void)
175{
176 i2c_del_adapter(&sibyte_board_adapter[0]);
177 i2c_del_adapter(&sibyte_board_adapter[1]);
178}
179
180module_init(i2c_sibyte_init);
181module_exit(i2c_sibyte_exit);
182
183MODULE_AUTHOR("Kip Walker (Broadcom Corp.)");
184MODULE_AUTHOR("Steven J. Hill <sjhill@realitydiluted.com>");
185MODULE_DESCRIPTION("SMBus adapter routines for SiByte boards");
186MODULE_LICENSE("GPL");
187
