diff options
Diffstat (limited to 'drivers/i2c/algos/i2c-algo-sibyte.c')
-rw-r--r-- | drivers/i2c/algos/i2c-algo-sibyte.c | 222 |
1 files changed, 222 insertions, 0 deletions
diff --git a/drivers/i2c/algos/i2c-algo-sibyte.c b/drivers/i2c/algos/i2c-algo-sibyte.c new file mode 100644 index 000000000000..35789bb7126a --- /dev/null +++ b/drivers/i2c/algos/i2c-algo-sibyte.c | |||
@@ -0,0 +1,222 @@ | |||
1 | /* ------------------------------------------------------------------------- */ | ||
2 | /* i2c-algo-sibyte.c i2c driver algorithms for bit-shift adapters */ | ||
3 | /* ------------------------------------------------------------------------- */ | ||
4 | /* Copyright (C) 2001,2002,2003 Broadcom Corporation | ||
5 | Copyright (C) 1995-2000 Simon G. Vogl | ||
6 | |||
7 | This program is free software; you can redistribute it and/or modify | ||
8 | it under the terms of the GNU General Public License as published by | ||
9 | the Free Software Foundation; either version 2 of the License, or | ||
10 | (at your option) any later version. | ||
11 | |||
12 | This program is distributed in the hope that it will be useful, | ||
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
15 | GNU General Public License for more details. | ||
16 | |||
17 | You should have received a copy of the GNU General Public License | ||
18 | along with this program; if not, write to the Free Software | ||
19 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ | ||
20 | /* ------------------------------------------------------------------------- */ | ||
21 | |||
22 | /* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and even | ||
23 | Frodo Looijaard <frodol@dds.nl>. */ | ||
24 | |||
25 | /* Ported for SiByte SOCs by Broadcom Corporation. */ | ||
26 | |||
27 | #include <linux/config.h> | ||
28 | #include <linux/kernel.h> | ||
29 | #include <linux/module.h> | ||
30 | #include <linux/init.h> | ||
31 | |||
32 | #include <asm/io.h> | ||
33 | #include <asm/sibyte/sb1250_regs.h> | ||
34 | #include <asm/sibyte/sb1250_smbus.h> | ||
35 | |||
36 | #include <linux/i2c.h> | ||
37 | #include <linux/i2c-algo-sibyte.h> | ||
38 | |||
39 | /* ----- global defines ----------------------------------------------- */ | ||
40 | #define SMB_CSR(a,r) ((long)(a->reg_base + r)) | ||
41 | |||
42 | /* ----- global variables --------------------------------------------- */ | ||
43 | |||
44 | /* module parameters: | ||
45 | */ | ||
46 | static int bit_scan=0; /* have a look at what's hanging 'round */ | ||
47 | |||
48 | |||
49 | static int smbus_xfer(struct i2c_adapter *i2c_adap, u16 addr, | ||
50 | unsigned short flags, char read_write, | ||
51 | u8 command, int size, union i2c_smbus_data * data) | ||
52 | { | ||
53 | struct i2c_algo_sibyte_data *adap = i2c_adap->algo_data; | ||
54 | int data_bytes = 0; | ||
55 | int error; | ||
56 | |||
57 | while (csr_in32(SMB_CSR(adap, R_SMB_STATUS)) & M_SMB_BUSY) | ||
58 | ; | ||
59 | |||
60 | switch (size) { | ||
61 | case I2C_SMBUS_QUICK: | ||
62 | csr_out32((V_SMB_ADDR(addr) | (read_write == I2C_SMBUS_READ ? M_SMB_QDATA : 0) | | ||
63 | V_SMB_TT_QUICKCMD), SMB_CSR(adap, R_SMB_START)); | ||
64 | break; | ||
65 | case I2C_SMBUS_BYTE: | ||
66 | if (read_write == I2C_SMBUS_READ) { | ||
67 | csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_RD1BYTE), | ||
68 | SMB_CSR(adap, R_SMB_START)); | ||
69 | data_bytes = 1; | ||
70 | } else { | ||
71 | csr_out32(V_SMB_CMD(command), SMB_CSR(adap, R_SMB_CMD)); | ||
72 | csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_WR1BYTE), | ||
73 | SMB_CSR(adap, R_SMB_START)); | ||
74 | } | ||
75 | break; | ||
76 | case I2C_SMBUS_BYTE_DATA: | ||
77 | csr_out32(V_SMB_CMD(command), SMB_CSR(adap, R_SMB_CMD)); | ||
78 | if (read_write == I2C_SMBUS_READ) { | ||
79 | csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_CMD_RD1BYTE), | ||
80 | SMB_CSR(adap, R_SMB_START)); | ||
81 | data_bytes = 1; | ||
82 | } else { | ||
83 | csr_out32(V_SMB_LB(data->byte), SMB_CSR(adap, R_SMB_DATA)); | ||
84 | csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_WR2BYTE), | ||
85 | SMB_CSR(adap, R_SMB_START)); | ||
86 | } | ||
87 | break; | ||
88 | case I2C_SMBUS_WORD_DATA: | ||
89 | csr_out32(V_SMB_CMD(command), SMB_CSR(adap, R_SMB_CMD)); | ||
90 | if (read_write == I2C_SMBUS_READ) { | ||
91 | csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_CMD_RD2BYTE), | ||
92 | SMB_CSR(adap, R_SMB_START)); | ||
93 | data_bytes = 2; | ||
94 | } else { | ||
95 | csr_out32(V_SMB_LB(data->word & 0xff), SMB_CSR(adap, R_SMB_DATA)); | ||
96 | csr_out32(V_SMB_MB(data->word >> 8), SMB_CSR(adap, R_SMB_DATA)); | ||
97 | csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_WR2BYTE), | ||
98 | SMB_CSR(adap, R_SMB_START)); | ||
99 | } | ||
100 | break; | ||
101 | default: | ||
102 | return -1; /* XXXKW better error code? */ | ||
103 | } | ||
104 | |||
105 | while (csr_in32(SMB_CSR(adap, R_SMB_STATUS)) & M_SMB_BUSY) | ||
106 | ; | ||
107 | |||
108 | error = csr_in32(SMB_CSR(adap, R_SMB_STATUS)); | ||
109 | if (error & M_SMB_ERROR) { | ||
110 | /* Clear error bit by writing a 1 */ | ||
111 | csr_out32(M_SMB_ERROR, SMB_CSR(adap, R_SMB_STATUS)); | ||
112 | return -1; /* XXXKW better error code? */ | ||
113 | } | ||
114 | |||
115 | if (data_bytes == 1) | ||
116 | data->byte = csr_in32(SMB_CSR(adap, R_SMB_DATA)) & 0xff; | ||
117 | if (data_bytes == 2) | ||
118 | data->word = csr_in32(SMB_CSR(adap, R_SMB_DATA)) & 0xffff; | ||
119 | |||
120 | return 0; | ||
121 | } | ||
122 | |||
123 | static int algo_control(struct i2c_adapter *adapter, | ||
124 | unsigned int cmd, unsigned long arg) | ||
125 | { | ||
126 | return 0; | ||
127 | } | ||
128 | |||
129 | static u32 bit_func(struct i2c_adapter *adap) | ||
130 | { | ||
131 | return (I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | | ||
132 | I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA); | ||
133 | } | ||
134 | |||
135 | |||
136 | /* -----exported algorithm data: ------------------------------------- */ | ||
137 | |||
138 | static struct i2c_algorithm i2c_sibyte_algo = { | ||
139 | .name = "SiByte algorithm", | ||
140 | .id = I2C_ALGO_SIBYTE, | ||
141 | .smbus_xfer = smbus_xfer, | ||
142 | .algo_control = algo_control, /* ioctl */ | ||
143 | .functionality = bit_func, | ||
144 | }; | ||
145 | |||
146 | /* | ||
147 | * registering functions to load algorithms at runtime | ||
148 | */ | ||
149 | int i2c_sibyte_add_bus(struct i2c_adapter *i2c_adap, int speed) | ||
150 | { | ||
151 | int i; | ||
152 | struct i2c_algo_sibyte_data *adap = i2c_adap->algo_data; | ||
153 | |||
154 | /* register new adapter to i2c module... */ | ||
155 | |||
156 | i2c_adap->id |= i2c_sibyte_algo.id; | ||
157 | i2c_adap->algo = &i2c_sibyte_algo; | ||
158 | |||
159 | /* Set the frequency to 100 kHz */ | ||
160 | csr_out32(speed, SMB_CSR(adap,R_SMB_FREQ)); | ||
161 | csr_out32(0, SMB_CSR(adap,R_SMB_CONTROL)); | ||
162 | |||
163 | /* scan bus */ | ||
164 | if (bit_scan) { | ||
165 | union i2c_smbus_data data; | ||
166 | int rc; | ||
167 | printk(KERN_INFO " i2c-algo-sibyte.o: scanning bus %s.\n", | ||
168 | i2c_adap->name); | ||
169 | for (i = 0x00; i < 0x7f; i++) { | ||
170 | /* XXXKW is this a realistic probe? */ | ||
171 | rc = smbus_xfer(i2c_adap, i, 0, I2C_SMBUS_READ, 0, | ||
172 | I2C_SMBUS_BYTE_DATA, &data); | ||
173 | if (!rc) { | ||
174 | printk("(%02x)",i); | ||
175 | } else | ||
176 | printk("."); | ||
177 | } | ||
178 | printk("\n"); | ||
179 | } | ||
180 | |||
181 | i2c_add_adapter(i2c_adap); | ||
182 | |||
183 | return 0; | ||
184 | } | ||
185 | |||
186 | |||
187 | int i2c_sibyte_del_bus(struct i2c_adapter *adap) | ||
188 | { | ||
189 | int res; | ||
190 | |||
191 | if ((res = i2c_del_adapter(adap)) < 0) | ||
192 | return res; | ||
193 | |||
194 | return 0; | ||
195 | } | ||
196 | |||
197 | int __init i2c_algo_sibyte_init (void) | ||
198 | { | ||
199 | printk("i2c-algo-sibyte.o: i2c SiByte algorithm module\n"); | ||
200 | return 0; | ||
201 | } | ||
202 | |||
203 | |||
204 | EXPORT_SYMBOL(i2c_sibyte_add_bus); | ||
205 | EXPORT_SYMBOL(i2c_sibyte_del_bus); | ||
206 | |||
207 | #ifdef MODULE | ||
208 | MODULE_AUTHOR("Kip Walker, Broadcom Corp."); | ||
209 | MODULE_DESCRIPTION("SiByte I2C-Bus algorithm"); | ||
210 | MODULE_PARM(bit_scan, "i"); | ||
211 | MODULE_PARM_DESC(bit_scan, "Scan for active chips on the bus"); | ||
212 | MODULE_LICENSE("GPL"); | ||
213 | |||
214 | int init_module(void) | ||
215 | { | ||
216 | return i2c_algo_sibyte_init(); | ||
217 | } | ||
218 | |||
219 | void cleanup_module(void) | ||
220 | { | ||
221 | } | ||
222 | #endif | ||