blob: f99a8161a9f14020a3c93966cb3432de9103f141 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 i2c-sensor-detect.c - Part of lm_sensors, Linux kernel modules for hardware
3 monitoring
4 Copyright (c) 1998 - 2001 Frodo Looijaard <frodol@dds.nl> and
5 Mark D. Studebaker <mdsxyz123@yahoo.com>
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#include <linux/module.h>
23#include <linux/kernel.h>
24#include <linux/i2c.h>
25#include <linux/i2c-sensor.h>
26
27static unsigned short empty[] = {I2C_CLIENT_END};
28static unsigned int empty_isa[] = {I2C_CLIENT_ISA_END};
29
30/* Very inefficient for ISA detects, and won't work for 10-bit addresses! */
31int i2c_detect(struct i2c_adapter *adapter,
32 struct i2c_address_data *address_data,
33 int (*found_proc) (struct i2c_adapter *, int, int))
34{
35 int addr, i, found, j, err;
36 struct i2c_force_data *this_force;
37 int is_isa = i2c_is_isa_adapter(adapter);
38 int adapter_id =
39 is_isa ? ANY_I2C_ISA_BUS : i2c_adapter_id(adapter);
40 unsigned short *normal_i2c;
41 unsigned int *normal_isa;
42 unsigned short *probe;
43 unsigned short *ignore;
44
45 /* Forget it if we can't probe using SMBUS_QUICK */
46 if ((!is_isa) &&
47 !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_QUICK))
48 return -1;
49
50 /* Use default "empty" list if the adapter doesn't specify any */
51 normal_i2c = probe = ignore = empty;
52 normal_isa = empty_isa;
53 if (address_data->normal_i2c)
54 normal_i2c = address_data->normal_i2c;
55 if (address_data->normal_isa)
56 normal_isa = address_data->normal_isa;
57 if (address_data->probe)
58 probe = address_data->probe;
59 if (address_data->ignore)
60 ignore = address_data->ignore;
61
62 for (addr = 0x00; addr <= (is_isa ? 0xffff : 0x7f); addr++) {
63 if (!is_isa && i2c_check_addr(adapter, addr))
64 continue;
65
66 /* If it is in one of the force entries, we don't do any
67 detection at all */
68 found = 0;
69 for (i = 0; !found && (this_force = address_data->forces + i, this_force->force); i++) {
70 for (j = 0; !found && (this_force->force[j] != I2C_CLIENT_END); j += 2) {
71 if ( ((adapter_id == this_force->force[j]) ||
72 ((this_force->force[j] == ANY_I2C_BUS) && !is_isa)) &&
73 (addr == this_force->force[j + 1]) ) {
74 dev_dbg(&adapter->dev, "found force parameter for adapter %d, addr %04x\n", adapter_id, addr);
75 if ((err = found_proc(adapter, addr, this_force->kind)))
76 return err;
77 found = 1;
78 }
79 }
80 }
81 if (found)
82 continue;
83
84 /* If this address is in one of the ignores, we can forget about it
85 right now */
86 for (i = 0; !found && (ignore[i] != I2C_CLIENT_END); i += 2) {
87 if ( ((adapter_id == ignore[i]) ||
88 ((ignore[i] == ANY_I2C_BUS) &&
89 !is_isa)) &&
90 (addr == ignore[i + 1])) {
91 dev_dbg(&adapter->dev, "found ignore parameter for adapter %d, addr %04x\n", adapter_id, addr);
92 found = 1;
93 }
94 }
95 if (found)
96 continue;
97
98 /* Now, we will do a detection, but only if it is in the normal or
99 probe entries */
100 if (is_isa) {
101 for (i = 0; !found && (normal_isa[i] != I2C_CLIENT_ISA_END); i += 1) {
102 if (addr == normal_isa[i]) {
103 dev_dbg(&adapter->dev, "found normal isa entry for adapter %d, addr %04x\n", adapter_id, addr);
104 found = 1;
105 }
106 }
107 } else {
108 for (i = 0; !found && (normal_i2c[i] != I2C_CLIENT_END); i += 1) {
109 if (addr == normal_i2c[i]) {
110 found = 1;
111 dev_dbg(&adapter->dev, "found normal i2c entry for adapter %d, addr %02x\n", adapter_id, addr);
112 }
113 }
114 }
115
116 for (i = 0;
117 !found && (probe[i] != I2C_CLIENT_END);
118 i += 2) {
119 if (((adapter_id == probe[i]) ||
120 ((probe[i] == ANY_I2C_BUS) && !is_isa))
121 && (addr == probe[i + 1])) {
122 dev_dbg(&adapter->dev, "found probe parameter for adapter %d, addr %04x\n", adapter_id, addr);
123 found = 1;
124 }
125 }
126 if (!found)
127 continue;
128
129 /* OK, so we really should examine this address. First check
130 whether there is some client here at all! */
131 if (is_isa ||
132 (i2c_smbus_xfer (adapter, addr, 0, 0, 0, I2C_SMBUS_QUICK, NULL) >= 0))
133 if ((err = found_proc(adapter, addr, -1)))
134 return err;
135 }
136 return 0;
137}
138
139EXPORT_SYMBOL(i2c_detect);
140
141MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>, "
142 "Rudolf Marek <r.marek@sh.cvut.cz>");
143
144MODULE_DESCRIPTION("i2c-sensor driver");
145MODULE_LICENSE("GPL");