diff options
Diffstat (limited to 'Documentation/i2c/old-module-parameters')
| -rw-r--r-- | Documentation/i2c/old-module-parameters | 44 |
1 files changed, 0 insertions, 44 deletions
diff --git a/Documentation/i2c/old-module-parameters b/Documentation/i2c/old-module-parameters deleted file mode 100644 index 8e2b629d533c..000000000000 --- a/Documentation/i2c/old-module-parameters +++ /dev/null @@ -1,44 +0,0 @@ -I2C device driver binding control from user-space -================================================= - -Up to kernel 2.6.32, many i2c drivers used helper macros provided by -<linux/i2c.h> 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 <driver> probe=1,0x2d -# modprobe <driver> force=1,0x2d -# modprobe <driver> force_<device>=1,0x2d - -New method (sysfs interface): -# echo <device> 0x2d > /sys/bus/i2c/devices/i2c-1/new_device - -Preventing a driver from attaching to an I2C device ---------------------------------------------------- - -Old method (module parameters): -# modprobe <driver> ignore=1,0x2f - -New method (sysfs interface): -# echo dummy 0x2f > /sys/bus/i2c/devices/i2c-1/new_device -# modprobe <driver> - -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". |