diff options
Diffstat (limited to 'Documentation/i2c/writing-clients')
| -rw-r--r-- | Documentation/i2c/writing-clients | 35 |
1 files changed, 15 insertions, 20 deletions
diff --git a/Documentation/i2c/writing-clients b/Documentation/i2c/writing-clients index 91664be91ff..e6b546dd4f7 100644 --- a/Documentation/i2c/writing-clients +++ b/Documentation/i2c/writing-clients @@ -195,31 +195,28 @@ Probing classes (sensors) ------------------------- If you write a `sensors' driver, you use a slightly different interface. -As well as I2C addresses, we have to cope with ISA addresses. Also, we -use a enum of chip types. Don't forget to include `sensors.h'. +Also, we use a enum of chip types. Don't forget to include `sensors.h'. The following lists are used internally. They are all lists of integers. - normal_i2c: filled in by the module writer. Terminated by SENSORS_I2C_END. + normal_i2c: filled in by the module writer. Terminated by I2C_CLIENT_END. A list of I2C addresses which should normally be examined. - normal_isa: filled in by the module writer. Terminated by SENSORS_ISA_END. - A list of ISA addresses which should normally be examined. - probe: insmod parameter. Initialize this list with SENSORS_I2C_END values. - A list of pairs. The first value is a bus number (SENSORS_ISA_BUS for - the ISA bus, -1 for any I2C bus), the second is the address. These - addresses are also probed, as if they were in the 'normal' list. - ignore: insmod parameter. Initialize this list with SENSORS_I2C_END values. - A list of pairs. The first value is a bus number (SENSORS_ISA_BUS for - the ISA bus, -1 for any I2C bus), the second is the I2C address. These - addresses are never probed. This parameter overrules 'normal' and - 'probe', but not the 'force' lists. + probe: insmod parameter. Initialize this list with I2C_CLIENT_END values. + A list of pairs. The first value is a bus number (ANY_I2C_BUS for any + I2C bus), the second is the address. These addresses are also probed, + as if they were in the 'normal' list. + ignore: insmod parameter. Initialize this list with I2C_CLIENT_END values. + A list of pairs. The first value is a bus number (ANY_I2C_BUS for any + I2C bus), the second is the I2C address. These addresses are never + probed. This parameter overrules 'normal' and 'probe', but not the + 'force' lists. Also used is a list of pointers to sensors_force_data structures: force_data: insmod parameters. A list, ending with an element of which the force field is NULL. Each element contains the type of chip and a list of pairs. - The first value is a bus number (SENSORS_ISA_BUS for the ISA bus, - -1 for any I2C bus), the second is the address. + The first value is a bus number (ANY_I2C_BUS for any I2C bus), the + second is the address. These are automatically translated to insmod variables of the form force_foo. @@ -227,13 +224,11 @@ So we have a generic insmod variabled `force', and chip-specific variables `force_CHIPNAME'. Fortunately, as a module writer, you just have to define the `normal_i2c' -and `normal_isa' parameters, and define what chip names are used. -The complete declaration could look like this: +parameter, and define what chip names are used. The complete declaration +could look like this: /* Scan i2c addresses 0x37, and 0x48 to 0x4f */ static unsigned short normal_i2c[] = { 0x37, 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, I2C_CLIENT_END }; - /* Scan ISA address 0x290 */ - static unsigned int normal_isa[] = {0x0290,SENSORS_ISA_END}; /* Define chips foo and bar, as well as all module parameters and things */ SENSORS_INSMOD_2(foo,bar); |