diff --git a/Documentation/i2c/old-module-parameters b/Documentation/i2c/old-module-parameters new file mode 100644 index 00000000000..8e2b629d533 --- /dev/null +++ b/Documentation/i2c/old-module-parameters @@ -0,0 +1,44 @@ +I2C device driver binding control from user-space +================================================= + +Up to kernel 2.6.32, many i2c drivers used helper macros provided by + which created standard module parameters to let the user +control how the driver would probe i2c buses and attach to devices. These +parameters were known as "probe" (to let the driver probe for an extra +address), "force" (to forcibly attach the driver to a given device) and +"ignore" (to prevent a driver from probing a given address). + +With the conversion of the i2c subsystem to the standard device driver +binding model, it became clear that these per-module parameters were no +longer needed, and that a centralized implementation was possible. The new, +sysfs-based interface is described in the documentation file +"instantiating-devices", section "Method 4: Instantiate from user-space". + +Below is a mapping from the old module parameters to the new interface. + +Attaching a driver to an I2C device +----------------------------------- + +Old method (module parameters): +# modprobe probe=1,0x2d +# modprobe force=1,0x2d +# modprobe force_=1,0x2d + +New method (sysfs interface): +# echo 0x2d > /sys/bus/i2c/devices/i2c-1/new_device + +Preventing a driver from attaching to an I2C device +--------------------------------------------------- + +Old method (module parameters): +# modprobe ignore=1,0x2f + +New method (sysfs interface): +# echo dummy 0x2f > /sys/bus/i2c/devices/i2c-1/new_device +# modprobe + +Of course, it is important to instantiate the "dummy" device before loading +the driver. The dummy device will be handled by i2c-core itself, preventing +other drivers from binding to it later on. If there is a real device at the +problematic address, and you want another driver to bind to it, then simply +pass the name of the device in question instead of "dummy". diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index d664b4a97a3..fdfaebdf3bf 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -1259,40 +1259,13 @@ static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver) return -ENOMEM; temp_client->adapter = adapter; - /* Force entries are done first, and are not affected by ignore - entries */ - if (address_data->forces) { - const unsigned short * const *forces = address_data->forces; - int kind; - - for (kind = 0; forces[kind]; kind++) { - for (i = 0; forces[kind][i] != I2C_CLIENT_END; - i += 2) { - if (forces[kind][i] == adap_id - || forces[kind][i] == ANY_I2C_BUS) { - dev_dbg(&adapter->dev, "found force " - "parameter for adapter %d, " - "addr 0x%02x, kind %d\n", - adap_id, forces[kind][i + 1], - kind); - temp_client->addr = forces[kind][i + 1]; - err = i2c_detect_address(temp_client, - kind, driver); - if (err) - goto exit_free; - } - } - } - } - /* Stop here if the classes do not match */ if (!(adapter->class & driver->class)) goto exit_free; /* Stop here if we can't use SMBUS_QUICK */ if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_QUICK)) { - if (address_data->probe[0] == I2C_CLIENT_END - && address_data->normal_i2c[0] == I2C_CLIENT_END) + if (address_data->normal_i2c[0] == I2C_CLIENT_END) goto exit_free; dev_warn(&adapter->dev, "SMBus Quick command not supported, " @@ -1301,43 +1274,7 @@ static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver) goto exit_free; } - /* Probe entries are done second, and are not affected by ignore - entries either */ - for (i = 0; address_data->probe[i] != I2C_CLIENT_END; i += 2) { - if (address_data->probe[i] == adap_id - || address_data->probe[i] == ANY_I2C_BUS) { - dev_dbg(&adapter->dev, "found probe parameter for " - "adapter %d, addr 0x%02x\n", adap_id, - address_data->probe[i + 1]); - temp_client->addr = address_data->probe[i + 1]; - err = i2c_detect_address(temp_client, -1, driver); - if (err) - goto exit_free; - } - } - - /* Normal entries are done last, unless shadowed by an ignore entry */ for (i = 0; address_data->normal_i2c[i] != I2C_CLIENT_END; i += 1) { - int j, ignore; - - ignore = 0; - for (j = 0; address_data->ignore[j] != I2C_CLIENT_END; - j += 2) { - if ((address_data->ignore[j] == adap_id || - address_data->ignore[j] == ANY_I2C_BUS) - && address_data->ignore[j + 1] - == address_data->normal_i2c[i]) { - dev_dbg(&adapter->dev, "found ignore " - "parameter for adapter %d, " - "addr 0x%02x\n", adap_id, - address_data->ignore[j + 1]); - ignore = 1; - break; - } - } - if (ignore) - continue; - dev_dbg(&adapter->dev, "found normal entry for adapter %d, " "addr 0x%02x\n", adap_id, address_data->normal_i2c[i]); diff --git a/include/linux/i2c.h b/include/linux/i2c.h index 52317fb5917..419ab546b26 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -110,7 +110,7 @@ extern s32 i2c_smbus_write_i2c_block_data(struct i2c_client *client, * @driver: Device driver model driver * @id_table: List of I2C devices supported by this driver * @detect: Callback for device detection - * @address_data: The I2C addresses to probe, ignore or force (for detect) + * @address_data: The I2C addresses to probe (for detect) * @clients: List of detected clients we created (for i2c-core use only) * * The driver.owner field should be set to the module owner of this driver. @@ -397,9 +397,6 @@ static inline void i2c_unlock_adapter(struct i2c_adapter *adapter) */ struct i2c_client_address_data { const unsigned short *normal_i2c; - const unsigned short *probe; - const unsigned short *ignore; - const unsigned short * const *forces; }; /* Internal numbers to terminate lists */ @@ -613,134 +610,48 @@ union i2c_smbus_data { module_param_array(var, short, &var##_num, 0); \ MODULE_PARM_DESC(var, desc) -#define I2C_CLIENT_MODULE_PARM_FORCE(name) \ -I2C_CLIENT_MODULE_PARM(force_##name, \ - "List of adapter,address pairs which are " \ - "unquestionably assumed to contain a `" \ - # name "' chip") - - #define I2C_CLIENT_INSMOD_COMMON \ -I2C_CLIENT_MODULE_PARM(probe, "List of adapter,address pairs to scan " \ - "additionally"); \ -I2C_CLIENT_MODULE_PARM(ignore, "List of adapter,address pairs not to " \ - "scan"); \ static const struct i2c_client_address_data addr_data = { \ .normal_i2c = normal_i2c, \ - .probe = probe, \ - .ignore = ignore, \ - .forces = forces, \ } -#define I2C_CLIENT_FORCE_TEXT \ - "List of adapter,address pairs to boldly assume to be present" - /* These are the ones you want to use in your own drivers. Pick the one which matches the number of devices the driver differenciates between. */ #define I2C_CLIENT_INSMOD \ -I2C_CLIENT_MODULE_PARM(force, I2C_CLIENT_FORCE_TEXT); \ -static const unsigned short * const forces[] = { force, NULL }; \ I2C_CLIENT_INSMOD_COMMON #define I2C_CLIENT_INSMOD_1(chip1) \ enum chips { any_chip, chip1 }; \ -I2C_CLIENT_MODULE_PARM(force, I2C_CLIENT_FORCE_TEXT); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip1); \ -static const unsigned short * const forces[] = { force, \ - force_##chip1, NULL }; \ I2C_CLIENT_INSMOD_COMMON #define I2C_CLIENT_INSMOD_2(chip1, chip2) \ enum chips { any_chip, chip1, chip2 }; \ -I2C_CLIENT_MODULE_PARM(force, I2C_CLIENT_FORCE_TEXT); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip1); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip2); \ -static const unsigned short * const forces[] = { force, \ - force_##chip1, force_##chip2, NULL }; \ I2C_CLIENT_INSMOD_COMMON #define I2C_CLIENT_INSMOD_3(chip1, chip2, chip3) \ enum chips { any_chip, chip1, chip2, chip3 }; \ -I2C_CLIENT_MODULE_PARM(force, I2C_CLIENT_FORCE_TEXT); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip1); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip2); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip3); \ -static const unsigned short * const forces[] = { force, \ - force_##chip1, force_##chip2, force_##chip3, NULL }; \ I2C_CLIENT_INSMOD_COMMON #define I2C_CLIENT_INSMOD_4(chip1, chip2, chip3, chip4) \ enum chips { any_chip, chip1, chip2, chip3, chip4 }; \ -I2C_CLIENT_MODULE_PARM(force, I2C_CLIENT_FORCE_TEXT); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip1); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip2); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip3); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip4); \ -static const unsigned short * const forces[] = { force, \ - force_##chip1, force_##chip2, force_##chip3, \ - force_##chip4, NULL}; \ I2C_CLIENT_INSMOD_COMMON #define I2C_CLIENT_INSMOD_5(chip1, chip2, chip3, chip4, chip5) \ enum chips { any_chip, chip1, chip2, chip3, chip4, chip5 }; \ -I2C_CLIENT_MODULE_PARM(force, I2C_CLIENT_FORCE_TEXT); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip1); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip2); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip3); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip4); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip5); \ -static const unsigned short * const forces[] = { force, \ - force_##chip1, force_##chip2, force_##chip3, \ - force_##chip4, force_##chip5, NULL }; \ I2C_CLIENT_INSMOD_COMMON #define I2C_CLIENT_INSMOD_6(chip1, chip2, chip3, chip4, chip5, chip6) \ enum chips { any_chip, chip1, chip2, chip3, chip4, chip5, chip6 }; \ -I2C_CLIENT_MODULE_PARM(force, I2C_CLIENT_FORCE_TEXT); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip1); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip2); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip3); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip4); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip5); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip6); \ -static const unsigned short * const forces[] = { force, \ - force_##chip1, force_##chip2, force_##chip3, \ - force_##chip4, force_##chip5, force_##chip6, NULL }; \ I2C_CLIENT_INSMOD_COMMON #define I2C_CLIENT_INSMOD_7(chip1, chip2, chip3, chip4, chip5, chip6, chip7) \ enum chips { any_chip, chip1, chip2, chip3, chip4, chip5, chip6, \ chip7 }; \ -I2C_CLIENT_MODULE_PARM(force, I2C_CLIENT_FORCE_TEXT); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip1); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip2); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip3); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip4); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip5); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip6); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip7); \ -static const unsigned short * const forces[] = { force, \ - force_##chip1, force_##chip2, force_##chip3, \ - force_##chip4, force_##chip5, force_##chip6, \ - force_##chip7, NULL }; \ I2C_CLIENT_INSMOD_COMMON #define I2C_CLIENT_INSMOD_8(chip1, chip2, chip3, chip4, chip5, chip6, chip7, chip8) \ enum chips { any_chip, chip1, chip2, chip3, chip4, chip5, chip6, \ chip7, chip8 }; \ -I2C_CLIENT_MODULE_PARM(force, I2C_CLIENT_FORCE_TEXT); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip1); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip2); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip3); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip4); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip5); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip6); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip7); \ -I2C_CLIENT_MODULE_PARM_FORCE(chip8); \ -static const unsigned short * const forces[] = { force, \ - force_##chip1, force_##chip2, force_##chip3, \ - force_##chip4, force_##chip5, force_##chip6, \ - force_##chip7, force_##chip8, NULL }; \ I2C_CLIENT_INSMOD_COMMON #endif /* __KERNEL__ */ #endif /* _LINUX_I2C_H */