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authorLinus Torvalds <torvalds@linux-foundation.org>2009-12-08 11:12:16 -0500
committerLinus Torvalds <torvalds@linux-foundation.org>2009-12-08 11:12:16 -0500
commit41440ffe21f29bdb985cab76b2d0b06d83e63b19 (patch)
tree1d7d1ff6f699ccbabb71c7bc4172f7d15bc4bc45 /Documentation
parentdad3de7d0090280f44ff27131ed2878f1ab6ddad (diff)
parent6471b68982d3bb1a593c3e183c804ecf830125d3 (diff)
Merge branch 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging
* 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging: i2c-stub: Documentation update i2c-stub: Allow user to disable some commands i2c-stub: Implement I2C block support i2c: Refactor for_each callbacks i2c-i801: Retry on lost arbitration i2c: Remove big kernel lock from i2cdev_open ics932s401: Clean up detect function i2c: Simplify i2c_detect_address i2c: Drop probe, ignore and force module parameters i2c: Add missing __devinit markers to old i2c adapter drivers i2c: Bus drivers don't have to support I2C_M_REV_DIR_ADDR i2c: Prevent priority inversion on top of bus lock i2c-voodoo3: Delete i2c-powermac: Drop temporary name buffer i2c-powermac: Include the i2c_adapter in struct pmac_i2c_bus i2c-powermac: Log errors i2c-powermac: Refactor i2c_powermac_smbus_xfer i2c-powermac: Reject unsupported I2C transactions i2c/chips: Move ds1682 to drivers/misc
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/feature-removal-schedule.txt9
-rw-r--r--Documentation/i2c/busses/i2c-voodoo362
-rw-r--r--Documentation/i2c/i2c-stub16
-rw-r--r--Documentation/i2c/old-module-parameters44
4 files changed, 55 insertions, 76 deletions
diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
index a004b04ffd3a..591e94448e63 100644
--- a/Documentation/feature-removal-schedule.txt
+++ b/Documentation/feature-removal-schedule.txt
@@ -407,15 +407,6 @@ Who: Alex Chiang <achiang@hp.com>
407 407
408--------------------------- 408---------------------------
409 409
410What: i2c-voodoo3 driver
411When: October 2009
412Why: Superseded by tdfxfb. I2C/DDC support used to live in a separate
413 driver but this caused driver conflicts.
414Who: Jean Delvare <khali@linux-fr.org>
415 Krzysztof Helt <krzysztof.h1@wp.pl>
416
417---------------------------
418
419What: CONFIG_RFKILL_INPUT 410What: CONFIG_RFKILL_INPUT
420When: 2.6.33 411When: 2.6.33
421Why: Should be implemented in userspace, policy daemon. 412Why: Should be implemented in userspace, policy daemon.
diff --git a/Documentation/i2c/busses/i2c-voodoo3 b/Documentation/i2c/busses/i2c-voodoo3
deleted file mode 100644
index 62d90a454d39..000000000000
--- a/Documentation/i2c/busses/i2c-voodoo3
+++ /dev/null
@@ -1,62 +0,0 @@
1Kernel driver i2c-voodoo3
2
3Supported adapters:
4 * 3dfx Voodoo3 based cards
5 * Voodoo Banshee based cards
6
7Authors:
8 Frodo Looijaard <frodol@dds.nl>,
9 Philip Edelbrock <phil@netroedge.com>,
10 Ralph Metzler <rjkm@thp.uni-koeln.de>,
11 Mark D. Studebaker <mdsxyz123@yahoo.com>
12
13Main contact: Philip Edelbrock <phil@netroedge.com>
14
15The code is based upon Ralph's test code (he did the hard stuff ;')
16
17Description
18-----------
19
20The 3dfx Voodoo3 chip contains two I2C interfaces (aka a I2C 'master' or
21'host').
22
23The first interface is used for DDC (Data Display Channel) which is a
24serial channel through the VGA monitor connector to a DDC-compliant
25monitor. This interface is defined by the Video Electronics Standards
26Association (VESA). The standards are available for purchase at
27http://www.vesa.org .
28
29The second interface is a general-purpose I2C bus. The intent by 3dfx was
30to allow manufacturers to add extra chips to the video card such as a
31TV-out chip such as the BT869 or possibly even I2C based temperature
32sensors like the ADM1021 or LM75.
33
34Stability
35---------
36
37Seems to be stable on the test machine, but needs more testing on other
38machines. Simultaneous accesses of the DDC and I2C busses may cause errors.
39
40Supported Devices
41-----------------
42
43Specifically, this driver was written and tested on the '3dfx Voodoo3 AGP
443000' which has a tv-out feature (s-video or composite). According to the
45docs and discussions, this code should work for any Voodoo3 based cards as
46well as Voodoo Banshee based cards. The DDC interface has been tested on a
47Voodoo Banshee card.
48
49Issues
50------
51
52Probably many, but it seems to work OK on my system. :')
53
54
55External Device Connection
56--------------------------
57
58The digital video input jumpers give availability to the I2C bus.
59Specifically, pins 13 and 25 (bottom row middle, and bottom right-end) are
60the I2C clock and I2C data lines, respectively. +5V and GND are probably
61also easily available making the addition of extra I2C/SMBus devices easy
62to implement.
diff --git a/Documentation/i2c/i2c-stub b/Documentation/i2c/i2c-stub
index 0d8be1c20c16..fa4b669c166b 100644
--- a/Documentation/i2c/i2c-stub
+++ b/Documentation/i2c/i2c-stub
@@ -2,9 +2,9 @@ MODULE: i2c-stub
2 2
3DESCRIPTION: 3DESCRIPTION:
4 4
5This module is a very simple fake I2C/SMBus driver. It implements four 5This module is a very simple fake I2C/SMBus driver. It implements five
6types of SMBus commands: write quick, (r/w) byte, (r/w) byte data, and 6types of SMBus commands: write quick, (r/w) byte, (r/w) byte data, (r/w)
7(r/w) word data. 7word data, and (r/w) I2C block data.
8 8
9You need to provide chip addresses as a module parameter when loading this 9You need to provide chip addresses as a module parameter when loading this
10driver, which will then only react to SMBus commands to these addresses. 10driver, which will then only react to SMBus commands to these addresses.
@@ -21,8 +21,8 @@ EEPROMs, among others.
21 21
22The typical use-case is like this: 22The typical use-case is like this:
23 1. load this module 23 1. load this module
24 2. use i2cset (from lm_sensors project) to pre-load some data 24 2. use i2cset (from the i2c-tools project) to pre-load some data
25 3. load the target sensors chip driver module 25 3. load the target chip driver module
26 4. observe its behavior in the kernel log 26 4. observe its behavior in the kernel log
27 27
28There's a script named i2c-stub-from-dump in the i2c-tools package which 28There's a script named i2c-stub-from-dump in the i2c-tools package which
@@ -33,6 +33,12 @@ PARAMETERS:
33int chip_addr[10]: 33int chip_addr[10]:
34 The SMBus addresses to emulate chips at. 34 The SMBus addresses to emulate chips at.
35 35
36unsigned long functionality:
37 Functionality override, to disable some commands. See I2C_FUNC_*
38 constants in <linux/i2c.h> for the suitable values. For example,
39 value 0x1f0000 would only enable the quick, byte and byte data
40 commands.
41
36CAVEATS: 42CAVEATS:
37 43
38If your target driver polls some byte or word waiting for it to change, the 44If your target driver polls some byte or word waiting for it to change, the
diff --git a/Documentation/i2c/old-module-parameters b/Documentation/i2c/old-module-parameters
new file mode 100644
index 000000000000..8e2b629d533c
--- /dev/null
+++ b/Documentation/i2c/old-module-parameters
@@ -0,0 +1,44 @@
1I2C device driver binding control from user-space
2=================================================
3
4Up to kernel 2.6.32, many i2c drivers used helper macros provided by
5<linux/i2c.h> which created standard module parameters to let the user
6control how the driver would probe i2c buses and attach to devices. These
7parameters were known as "probe" (to let the driver probe for an extra
8address), "force" (to forcibly attach the driver to a given device) and
9"ignore" (to prevent a driver from probing a given address).
10
11With the conversion of the i2c subsystem to the standard device driver
12binding model, it became clear that these per-module parameters were no
13longer needed, and that a centralized implementation was possible. The new,
14sysfs-based interface is described in the documentation file
15"instantiating-devices", section "Method 4: Instantiate from user-space".
16
17Below is a mapping from the old module parameters to the new interface.
18
19Attaching a driver to an I2C device
20-----------------------------------
21
22Old method (module parameters):
23# modprobe <driver> probe=1,0x2d
24# modprobe <driver> force=1,0x2d
25# modprobe <driver> force_<device>=1,0x2d
26
27New method (sysfs interface):
28# echo <device> 0x2d > /sys/bus/i2c/devices/i2c-1/new_device
29
30Preventing a driver from attaching to an I2C device
31---------------------------------------------------
32
33Old method (module parameters):
34# modprobe <driver> ignore=1,0x2f
35
36New method (sysfs interface):
37# echo dummy 0x2f > /sys/bus/i2c/devices/i2c-1/new_device
38# modprobe <driver>
39
40Of course, it is important to instantiate the "dummy" device before loading
41the driver. The dummy device will be handled by i2c-core itself, preventing
42other drivers from binding to it later on. If there is a real device at the
43problematic address, and you want another driver to bind to it, then simply
44pass the name of the device in question instead of "dummy".