drivers/i2c/i2c-sensor-detect.c

   1 /*
   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/config.h>
  23 #include <linux/module.h>
  24 #include <linux/kernel.h>
  25 #include <linux/slab.h>
  26 #include <linux/ctype.h>
  27 #include <linux/sysctl.h>
  28 #include <linux/init.h>
  29 #include <linux/ioport.h>
  30 #include <linux/i2c.h>
  31 #include <linux/i2c-sensor.h>
  32 #include <asm/uaccess.h>
  33
  34 static unsigned short empty[] = {I2C_CLIENT_END};
  35 static unsigned int empty_isa[] = {I2C_CLIENT_ISA_END};
  36
  37 /* Very inefficient for ISA detects, and won't work for 10-bit addresses! */
  38 int i2c_detect(struct i2c_adapter *adapter,
  39                struct i2c_address_data *address_data,
  40                int (*found_proc) (struct i2c_adapter *, int, int))
  41 {
  42         int addr, i, found, j, err;
  43         struct i2c_force_data *this_force;
  44         int is_isa = i2c_is_isa_adapter(adapter);
  45         int adapter_id =
  46             is_isa ? ANY_I2C_ISA_BUS : i2c_adapter_id(adapter);
  47         unsigned short *normal_i2c;
  48         unsigned int *normal_isa;
  49         unsigned short *probe;
  50         unsigned short *ignore;
  51
  52         /* Forget it if we can't probe using SMBUS_QUICK */
  53         if ((!is_isa) &&
  54             !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_QUICK))
  55                 return -1;
  56
  57         /* Use default "empty" list if the adapter doesn't specify any */
  58         normal_i2c = probe = ignore = empty;
  59         normal_isa = empty_isa;
  60         if (address_data->normal_i2c)
  61                 normal_i2c = address_data->normal_i2c;
  62         if (address_data->normal_isa)
  63                 normal_isa = address_data->normal_isa;
  64         if (address_data->probe)
  65                 probe = address_data->probe;
  66         if (address_data->ignore)
  67                 ignore = address_data->ignore;
  68
  69         for (addr = 0x00; addr <= (is_isa ? 0xffff : 0x7f); addr++) {
  70                 if (!is_isa && i2c_check_addr(adapter, addr))
  71                         continue;
  72
  73                 /* If it is in one of the force entries, we don't do any
  74                    detection at all */
  75                 found = 0;
  76                 for (i = 0; !found && (this_force = address_data->forces + i, this_force->force); i++) {
  77                         for (j = 0; !found && (this_force->force[j] != I2C_CLIENT_END); j += 2) {
  78                                 if ( ((adapter_id == this_force->force[j]) ||
  79                                       ((this_force->force[j] == ANY_I2C_BUS) && !is_isa)) &&
  80                                       (addr == this_force->force[j + 1]) ) {
  81                                         dev_dbg(&adapter->dev, "found force parameter for adapter %d, addr %04x\n", adapter_id, addr);
  82                                         if ((err = found_proc(adapter, addr, this_force->kind)))
  83                                                 return err;
  84                                         found = 1;
  85                                 }
  86                         }
  87                 }
  88                 if (found)
  89                         continue;
  90
  91                 /* If this address is in one of the ignores, we can forget about it
  92                    right now */
  93                 for (i = 0; !found && (ignore[i] != I2C_CLIENT_END); i += 2) {
  94                         if ( ((adapter_id == ignore[i]) ||
  95                               ((ignore[i] == ANY_I2C_BUS) &&
  96                                !is_isa)) &&
  97                               (addr == ignore[i + 1])) {
  98                                 dev_dbg(&adapter->dev, "found ignore parameter for adapter %d, addr %04x\n", adapter_id, addr);
  99                                 found = 1;
 100                         }
 101                 }
 102                 if (found)
 103                         continue;
 104
 105                 /* Now, we will do a detection, but only if it is in the normal or
 106                    probe entries */
 107                 if (is_isa) {
 108                         for (i = 0; !found && (normal_isa[i] != I2C_CLIENT_ISA_END); i += 1) {
 109                                 if (addr == normal_isa[i]) {
 110                                         dev_dbg(&adapter->dev, "found normal isa entry for adapter %d, addr %04x\n", adapter_id, addr);
 111                                         found = 1;
 112                                 }
 113                         }
 114                 } else {
 115                         for (i = 0; !found && (normal_i2c[i] != I2C_CLIENT_END); i += 1) {
 116                                 if (addr == normal_i2c[i]) {
 117                                         found = 1;
 118                                         dev_dbg(&adapter->dev, "found normal i2c entry for adapter %d, addr %02x\n", adapter_id, addr);
 119                                 }
 120                         }
 121                 }
 122
 123                 for (i = 0;
 124                      !found && (probe[i] != I2C_CLIENT_END);
 125                      i += 2) {
 126                         if (((adapter_id == probe[i]) ||
 127                              ((probe[i] == ANY_I2C_BUS) && !is_isa))
 128                             && (addr == probe[i + 1])) {
 129                                 dev_dbg(&adapter->dev, "found probe parameter for adapter %d, addr %04x\n", adapter_id, addr);
 130                                 found = 1;
 131                         }
 132                 }
 133                 if (!found)
 134                         continue;
 135
 136                 /* OK, so we really should examine this address. First check
 137                    whether there is some client here at all! */
 138                 if (is_isa ||
 139                     (i2c_smbus_xfer (adapter, addr, 0, 0, 0, I2C_SMBUS_QUICK, NULL) >= 0))
 140                         if ((err = found_proc(adapter, addr, -1)))
 141                                 return err;
 142         }
 143         return 0;
 144 }
 145
 146 EXPORT_SYMBOL(i2c_detect);
 147
 148 MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>, "
 149               "Rudolf Marek <r.marek@sh.cvut.cz>");
 150
 151 MODULE_DESCRIPTION("i2c-sensor driver");
 152 MODULE_LICENSE("GPL");