diff options
Diffstat (limited to 'drivers/i2c/algos/i2c-algo-sgi.c')
-rw-r--r-- | drivers/i2c/algos/i2c-algo-sgi.c | 179 |
1 files changed, 0 insertions, 179 deletions
diff --git a/drivers/i2c/algos/i2c-algo-sgi.c b/drivers/i2c/algos/i2c-algo-sgi.c deleted file mode 100644 index 6eaf145e1ada..000000000000 --- a/drivers/i2c/algos/i2c-algo-sgi.c +++ /dev/null | |||
@@ -1,179 +0,0 @@ | |||
1 | /* | ||
2 | * i2c-algo-sgi.c: i2c driver algorithm used by the VINO (SGI Indy) and | ||
3 | * MACE (SGI O2) chips. | ||
4 | * | ||
5 | * This file is subject to the terms and conditions of the GNU General Public | ||
6 | * License version 2 as published by the Free Software Foundation. | ||
7 | * | ||
8 | * Copyright (C) 2003 Ladislav Michl <ladis@linux-mips.org> | ||
9 | */ | ||
10 | |||
11 | #include <linux/kernel.h> | ||
12 | #include <linux/module.h> | ||
13 | #include <linux/init.h> | ||
14 | #include <linux/errno.h> | ||
15 | #include <linux/delay.h> | ||
16 | |||
17 | #include <linux/i2c.h> | ||
18 | #include <linux/i2c-algo-sgi.h> | ||
19 | |||
20 | |||
21 | #define SGI_I2C_FORCE_IDLE (0 << 0) | ||
22 | #define SGI_I2C_NOT_IDLE (1 << 0) | ||
23 | #define SGI_I2C_WRITE (0 << 1) | ||
24 | #define SGI_I2C_READ (1 << 1) | ||
25 | #define SGI_I2C_RELEASE_BUS (0 << 2) | ||
26 | #define SGI_I2C_HOLD_BUS (1 << 2) | ||
27 | #define SGI_I2C_XFER_DONE (0 << 4) | ||
28 | #define SGI_I2C_XFER_BUSY (1 << 4) | ||
29 | #define SGI_I2C_ACK (0 << 5) | ||
30 | #define SGI_I2C_NACK (1 << 5) | ||
31 | #define SGI_I2C_BUS_OK (0 << 7) | ||
32 | #define SGI_I2C_BUS_ERR (1 << 7) | ||
33 | |||
34 | #define get_control() adap->getctrl(adap->data) | ||
35 | #define set_control(val) adap->setctrl(adap->data, val) | ||
36 | #define read_data() adap->rdata(adap->data) | ||
37 | #define write_data(val) adap->wdata(adap->data, val) | ||
38 | |||
39 | |||
40 | static int wait_xfer_done(struct i2c_algo_sgi_data *adap) | ||
41 | { | ||
42 | int i; | ||
43 | |||
44 | for (i = 0; i < adap->xfer_timeout; i++) { | ||
45 | if ((get_control() & SGI_I2C_XFER_BUSY) == 0) | ||
46 | return 0; | ||
47 | udelay(1); | ||
48 | } | ||
49 | |||
50 | return -ETIMEDOUT; | ||
51 | } | ||
52 | |||
53 | static int wait_ack(struct i2c_algo_sgi_data *adap) | ||
54 | { | ||
55 | int i; | ||
56 | |||
57 | if (wait_xfer_done(adap)) | ||
58 | return -ETIMEDOUT; | ||
59 | for (i = 0; i < adap->ack_timeout; i++) { | ||
60 | if ((get_control() & SGI_I2C_NACK) == 0) | ||
61 | return 0; | ||
62 | udelay(1); | ||
63 | } | ||
64 | |||
65 | return -ETIMEDOUT; | ||
66 | } | ||
67 | |||
68 | static int force_idle(struct i2c_algo_sgi_data *adap) | ||
69 | { | ||
70 | int i; | ||
71 | |||
72 | set_control(SGI_I2C_FORCE_IDLE); | ||
73 | for (i = 0; i < adap->xfer_timeout; i++) { | ||
74 | if ((get_control() & SGI_I2C_NOT_IDLE) == 0) | ||
75 | goto out; | ||
76 | udelay(1); | ||
77 | } | ||
78 | return -ETIMEDOUT; | ||
79 | out: | ||
80 | if (get_control() & SGI_I2C_BUS_ERR) | ||
81 | return -EIO; | ||
82 | return 0; | ||
83 | } | ||
84 | |||
85 | static int do_address(struct i2c_algo_sgi_data *adap, unsigned int addr, | ||
86 | int rd) | ||
87 | { | ||
88 | if (rd) | ||
89 | set_control(SGI_I2C_NOT_IDLE); | ||
90 | /* Check if bus is idle, eventually force it to do so */ | ||
91 | if (get_control() & SGI_I2C_NOT_IDLE) | ||
92 | if (force_idle(adap)) | ||
93 | return -EIO; | ||
94 | /* Write out the i2c chip address and specify operation */ | ||
95 | set_control(SGI_I2C_HOLD_BUS | SGI_I2C_WRITE | SGI_I2C_NOT_IDLE); | ||
96 | if (rd) | ||
97 | addr |= 1; | ||
98 | write_data(addr); | ||
99 | if (wait_ack(adap)) | ||
100 | return -EIO; | ||
101 | return 0; | ||
102 | } | ||
103 | |||
104 | static int i2c_read(struct i2c_algo_sgi_data *adap, unsigned char *buf, | ||
105 | unsigned int len) | ||
106 | { | ||
107 | int i; | ||
108 | |||
109 | set_control(SGI_I2C_HOLD_BUS | SGI_I2C_READ | SGI_I2C_NOT_IDLE); | ||
110 | for (i = 0; i < len; i++) { | ||
111 | if (wait_xfer_done(adap)) | ||
112 | return -EIO; | ||
113 | buf[i] = read_data(); | ||
114 | } | ||
115 | set_control(SGI_I2C_RELEASE_BUS | SGI_I2C_FORCE_IDLE); | ||
116 | |||
117 | return 0; | ||
118 | |||
119 | } | ||
120 | |||
121 | static int i2c_write(struct i2c_algo_sgi_data *adap, unsigned char *buf, | ||
122 | unsigned int len) | ||
123 | { | ||
124 | int i; | ||
125 | |||
126 | /* We are already in write state */ | ||
127 | for (i = 0; i < len; i++) { | ||
128 | write_data(buf[i]); | ||
129 | if (wait_ack(adap)) | ||
130 | return -EIO; | ||
131 | } | ||
132 | return 0; | ||
133 | } | ||
134 | |||
135 | static int sgi_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, | ||
136 | int num) | ||
137 | { | ||
138 | struct i2c_algo_sgi_data *adap = i2c_adap->algo_data; | ||
139 | struct i2c_msg *p; | ||
140 | int i, err = 0; | ||
141 | |||
142 | for (i = 0; !err && i < num; i++) { | ||
143 | p = &msgs[i]; | ||
144 | err = do_address(adap, p->addr, p->flags & I2C_M_RD); | ||
145 | if (err || !p->len) | ||
146 | continue; | ||
147 | if (p->flags & I2C_M_RD) | ||
148 | err = i2c_read(adap, p->buf, p->len); | ||
149 | else | ||
150 | err = i2c_write(adap, p->buf, p->len); | ||
151 | } | ||
152 | |||
153 | return (err < 0) ? err : i; | ||
154 | } | ||
155 | |||
156 | static u32 sgi_func(struct i2c_adapter *adap) | ||
157 | { | ||
158 | return I2C_FUNC_SMBUS_EMUL; | ||
159 | } | ||
160 | |||
161 | static const struct i2c_algorithm sgi_algo = { | ||
162 | .master_xfer = sgi_xfer, | ||
163 | .functionality = sgi_func, | ||
164 | }; | ||
165 | |||
166 | /* | ||
167 | * registering functions to load algorithms at runtime | ||
168 | */ | ||
169 | int i2c_sgi_add_bus(struct i2c_adapter *adap) | ||
170 | { | ||
171 | adap->algo = &sgi_algo; | ||
172 | |||
173 | return i2c_add_adapter(adap); | ||
174 | } | ||
175 | EXPORT_SYMBOL(i2c_sgi_add_bus); | ||
176 | |||
177 | MODULE_AUTHOR("Ladislav Michl <ladis@linux-mips.org>"); | ||
178 | MODULE_DESCRIPTION("I2C-Bus SGI algorithm"); | ||
179 | MODULE_LICENSE("GPL"); | ||