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-rw-r--r--Documentation/i2c/busses/i2c-i8013
-rw-r--r--Documentation/i2c/busses/i2c-parport3
-rw-r--r--Documentation/i2c/busses/i2c-parport-light11
-rw-r--r--Documentation/i2c/busses/i2c-voodoo362
-rw-r--r--Documentation/i2c/i2c-stub16
-rw-r--r--Documentation/i2c/old-module-parameters44
-rw-r--r--Documentation/i2c/smbus-protocol16
-rw-r--r--Documentation/i2c/writing-clients12
8 files changed, 96 insertions, 71 deletions
diff --git a/Documentation/i2c/busses/i2c-i801 b/Documentation/i2c/busses/i2c-i801
index 81c0c59a60ea..e1bb5b261693 100644
--- a/Documentation/i2c/busses/i2c-i801
+++ b/Documentation/i2c/busses/i2c-i801
@@ -15,7 +15,8 @@ Supported adapters:
15 * Intel 82801I (ICH9) 15 * Intel 82801I (ICH9)
16 * Intel EP80579 (Tolapai) 16 * Intel EP80579 (Tolapai)
17 * Intel 82801JI (ICH10) 17 * Intel 82801JI (ICH10)
18 * Intel PCH 18 * Intel 3400/5 Series (PCH)
19 * Intel Cougar Point (PCH)
19 Datasheets: Publicly available at the Intel website 20 Datasheets: Publicly available at the Intel website
20 21
21Authors: 22Authors:
diff --git a/Documentation/i2c/busses/i2c-parport b/Documentation/i2c/busses/i2c-parport
index dceaba1ad930..2461c7b53b2c 100644
--- a/Documentation/i2c/busses/i2c-parport
+++ b/Documentation/i2c/busses/i2c-parport
@@ -29,6 +29,9 @@ can be easily added when needed.
29Earlier kernels defaulted to type=0 (Philips). But now, if the type 29Earlier kernels defaulted to type=0 (Philips). But now, if the type
30parameter is missing, the driver will simply fail to initialize. 30parameter is missing, the driver will simply fail to initialize.
31 31
32SMBus alert support is available on adapters which have this line properly
33connected to the parallel port's interrupt pin.
34
32 35
33Building your own adapter 36Building your own adapter
34------------------------- 37-------------------------
diff --git a/Documentation/i2c/busses/i2c-parport-light b/Documentation/i2c/busses/i2c-parport-light
index 287436478520..bdc9cbb2e0f2 100644
--- a/Documentation/i2c/busses/i2c-parport-light
+++ b/Documentation/i2c/busses/i2c-parport-light
@@ -9,3 +9,14 @@ parport handling is not an option. The drawback is a reduced portability
9and the impossibility to daisy-chain other parallel port devices. 9and the impossibility to daisy-chain other parallel port devices.
10 10
11Please see i2c-parport for documentation. 11Please see i2c-parport for documentation.
12
13Module parameters:
14
15* type: type of adapter (see i2c-parport or modinfo)
16
17* base: base I/O address
18 Default is 0x378 which is fairly common for parallel ports, at least on PC.
19
20* irq: optional IRQ
21 This must be passed if you want SMBus alert support, assuming your adapter
22 actually supports this.
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".
diff --git a/Documentation/i2c/smbus-protocol b/Documentation/i2c/smbus-protocol
index 9df47441f0e7..7c19d1a2bea0 100644
--- a/Documentation/i2c/smbus-protocol
+++ b/Documentation/i2c/smbus-protocol
@@ -185,6 +185,22 @@ the protocol. All ARP communications use slave address 0x61 and
185require PEC checksums. 185require PEC checksums.
186 186
187 187
188SMBus Alert
189===========
190
191SMBus Alert was introduced in Revision 1.0 of the specification.
192
193The SMBus alert protocol allows several SMBus slave devices to share a
194single interrupt pin on the SMBus master, while still allowing the master
195to know which slave triggered the interrupt.
196
197This is implemented the following way in the Linux kernel:
198* I2C bus drivers which support SMBus alert should call
199 i2c_setup_smbus_alert() to setup SMBus alert support.
200* I2C drivers for devices which can trigger SMBus alerts should implement
201 the optional alert() callback.
202
203
188I2C Block Transactions 204I2C Block Transactions
189====================== 205======================
190 206
diff --git a/Documentation/i2c/writing-clients b/Documentation/i2c/writing-clients
index 7860aafb483d..5ebf5af1d716 100644
--- a/Documentation/i2c/writing-clients
+++ b/Documentation/i2c/writing-clients
@@ -44,7 +44,7 @@ static struct i2c_driver foo_driver = {
44 /* if device autodetection is needed: */ 44 /* if device autodetection is needed: */
45 .class = I2C_CLASS_SOMETHING, 45 .class = I2C_CLASS_SOMETHING,
46 .detect = foo_detect, 46 .detect = foo_detect,
47 .address_data = &addr_data, 47 .address_list = normal_i2c,
48 48
49 .shutdown = foo_shutdown, /* optional */ 49 .shutdown = foo_shutdown, /* optional */
50 .suspend = foo_suspend, /* optional */ 50 .suspend = foo_suspend, /* optional */
@@ -74,6 +74,11 @@ structure at all. You should use this to keep device-specific data.
74 /* retrieve the value */ 74 /* retrieve the value */
75 void *i2c_get_clientdata(const struct i2c_client *client); 75 void *i2c_get_clientdata(const struct i2c_client *client);
76 76
77Note that starting with kernel 2.6.34, you don't have to set the `data' field
78to NULL in remove() or if probe() failed anymore. The i2c-core does this
79automatically on these occasions. Those are also the only times the core will
80touch this field.
81
77 82
78Accessing the client 83Accessing the client
79==================== 84====================
@@ -318,8 +323,9 @@ Plain I2C communication
318These routines read and write some bytes from/to a client. The client 323These routines read and write some bytes from/to a client. The client
319contains the i2c address, so you do not have to include it. The second 324contains the i2c address, so you do not have to include it. The second
320parameter contains the bytes to read/write, the third the number of bytes 325parameter contains the bytes to read/write, the third the number of bytes
321to read/write (must be less than the length of the buffer.) Returned is 326to read/write (must be less than the length of the buffer, also should be
322the actual number of bytes read/written. 327less than 64k since msg.len is u16.) Returned is the actual number of bytes
328read/written.
323 329
324 int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msg, 330 int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msg,
325 int num); 331 int num);