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Diffstat (limited to 'drivers/i2c/algos/i2c-algo-sibyte.c')
-rw-r--r--drivers/i2c/algos/i2c-algo-sibyte.c222
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 */
46static int bit_scan=0; /* have a look at what's hanging 'round */
47
48
49static 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
123static int algo_control(struct i2c_adapter *adapter,
124 unsigned int cmd, unsigned long arg)
125{
126 return 0;
127}
128
129static 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
138static 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 */
149int 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
187int 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
197int __init i2c_algo_sibyte_init (void)
198{
199 printk("i2c-algo-sibyte.o: i2c SiByte algorithm module\n");
200 return 0;
201}
202
203
204EXPORT_SYMBOL(i2c_sibyte_add_bus);
205EXPORT_SYMBOL(i2c_sibyte_del_bus);
206
207#ifdef MODULE
208MODULE_AUTHOR("Kip Walker, Broadcom Corp.");
209MODULE_DESCRIPTION("SiByte I2C-Bus algorithm");
210MODULE_PARM(bit_scan, "i");
211MODULE_PARM_DESC(bit_scan, "Scan for active chips on the bus");
212MODULE_LICENSE("GPL");
213
214int init_module(void)
215{
216 return i2c_algo_sibyte_init();
217}
218
219void cleanup_module(void)
220{
221}
222#endif