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-rw-r--r--Documentation/i2c/busses/i2c-i80160
-rw-r--r--Documentation/i2c/busses/i2c-parport15
-rw-r--r--Documentation/i2c/busses/i2c-piix42
-rw-r--r--Documentation/i2c/busses/i2c-viapro7
4 files changed, 78 insertions, 6 deletions
diff --git a/Documentation/i2c/busses/i2c-i801 b/Documentation/i2c/busses/i2c-i801
index 3db69a086c4..c34f0db78a3 100644
--- a/Documentation/i2c/busses/i2c-i801
+++ b/Documentation/i2c/busses/i2c-i801
@@ -48,14 +48,9 @@ following:
The SMBus controller is function 3 in device 1f. Class 0c05 is SMBus Serial
Controller.
-If you do NOT see the 24x3 device at function 3, and you can't figure out
-any way in the BIOS to enable it,
-
The ICH chips are quite similar to Intel's PIIX4 chip, at least in the
SMBus controller.
-See the file i2c-piix4 for some additional information.
-
Process Call Support
--------------------
@@ -74,6 +69,61 @@ SMBus 2.0 Support
The 82801DB (ICH4) and later chips support several SMBus 2.0 features.
+
+Hidden ICH SMBus
+----------------
+
+If your system has an Intel ICH south bridge, but you do NOT see the
+SMBus device at 00:1f.3 in lspci, and you can't figure out any way in the
+BIOS to enable it, it means it has been hidden by the BIOS code. Asus is
+well known for first doing this on their P4B motherboard, and many other
+boards after that. Some vendor machines are affected as well.
+
+The first thing to try is the "i2c_ec" ACPI driver. It could be that the
+SMBus was hidden on purpose because it'll be driven by ACPI. If the
+i2c_ec driver works for you, just forget about the i2c-i801 driver and
+don't try to unhide the ICH SMBus. Even if i2c_ec doesn't work, you
+better make sure that the SMBus isn't used by the ACPI code. Try loading
+the "fan" and "thermal" drivers, and check in /proc/acpi/fan and
+/proc/acpi/thermal_zone. If you find anything there, it's likely that
+the ACPI is accessing the SMBus and it's safer not to unhide it. Only
+once you are certain that ACPI isn't using the SMBus, you can attempt
+to unhide it.
+
+In order to unhide the SMBus, we need to change the value of a PCI
+register before the kernel enumerates the PCI devices. This is done in
+drivers/pci/quirks.c, where all affected boards must be listed (see
+function asus_hides_smbus_hostbridge.) If the SMBus device is missing,
+and you think there's something interesting on the SMBus (e.g. a
+hardware monitoring chip), you need to add your board to the list.
+
+The motherboard is identified using the subvendor and subdevice IDs of the
+host bridge PCI device. Get yours with "lspci -n -v -s 00:00.0":
+
+00:00.0 Class 0600: 8086:2570 (rev 02)
+ Subsystem: 1043:80f2
+ Flags: bus master, fast devsel, latency 0
+ Memory at fc000000 (32-bit, prefetchable) [size=32M]
+ Capabilities: [e4] #09 [2106]
+ Capabilities: [a0] AGP version 3.0
+
+Here the host bridge ID is 2570 (82865G/PE/P), the subvendor ID is 1043
+(Asus) and the subdevice ID is 80f2 (P4P800-X). You can find the symbolic
+names for the bridge ID and the subvendor ID in include/linux/pci_ids.h,
+and then add a case for your subdevice ID at the right place in
+drivers/pci/quirks.c. Then please give it very good testing, to make sure
+that the unhidden SMBus doesn't conflict with e.g. ACPI.
+
+If it works, proves useful (i.e. there are usable chips on the SMBus)
+and seems safe, please submit a patch for inclusion into the kernel.
+
+Note: There's a useful script in lm_sensors 2.10.2 and later, named
+unhide_ICH_SMBus (in prog/hotplug), which uses the fakephp driver to
+temporarily unhide the SMBus without having to patch and recompile your
+kernel. It's very convenient if you just want to check if there's
+anything interesting on your hidden ICH SMBus.
+
+
**********************
The lm_sensors project gratefully acknowledges the support of Texas
Instruments in the initial development of this driver.
diff --git a/Documentation/i2c/busses/i2c-parport b/Documentation/i2c/busses/i2c-parport
index 77b995dfca2..dceaba1ad93 100644
--- a/Documentation/i2c/busses/i2c-parport
+++ b/Documentation/i2c/busses/i2c-parport
@@ -19,6 +19,7 @@ It currently supports the following devices:
* (type=4) Analog Devices ADM1032 evaluation board
* (type=5) Analog Devices evaluation boards: ADM1025, ADM1030, ADM1031
* (type=6) Barco LPT->DVI (K5800236) adapter
+ * (type=7) One For All JP1 parallel port adapter
These devices use different pinout configurations, so you have to tell
the driver what you have, using the type module parameter. There is no
@@ -157,3 +158,17 @@ many more, using /dev/velleman.
http://home.wanadoo.nl/hihihi/libk8005.htm
http://struyve.mine.nu:8080/index.php?block=k8000
http://sourceforge.net/projects/libk8005/
+
+
+One For All JP1 parallel port adapter
+-------------------------------------
+
+The JP1 project revolves around a set of remote controls which expose
+the I2C bus their internal configuration EEPROM lives on via a 6 pin
+jumper in the battery compartment. More details can be found at:
+
+http://www.hifi-remote.com/jp1/
+
+Details of the simple parallel port hardware can be found at:
+
+http://www.hifi-remote.com/jp1/hardware.shtml
diff --git a/Documentation/i2c/busses/i2c-piix4 b/Documentation/i2c/busses/i2c-piix4
index 92147633323..7cbe43fa270 100644
--- a/Documentation/i2c/busses/i2c-piix4
+++ b/Documentation/i2c/busses/i2c-piix4
@@ -6,7 +6,7 @@ Supported adapters:
Datasheet: Publicly available at the Intel website
* ServerWorks OSB4, CSB5, CSB6 and HT-1000 southbridges
Datasheet: Only available via NDA from ServerWorks
- * ATI IXP southbridges IXP200, IXP300, IXP400
+ * ATI IXP200, IXP300, IXP400 and SB600 southbridges
Datasheet: Not publicly available
* Standard Microsystems (SMSC) SLC90E66 (Victory66) southbridge
Datasheet: Publicly available at the SMSC website http://www.smsc.com
diff --git a/Documentation/i2c/busses/i2c-viapro b/Documentation/i2c/busses/i2c-viapro
index 25680346e0a..775f489e86f 100644
--- a/Documentation/i2c/busses/i2c-viapro
+++ b/Documentation/i2c/busses/i2c-viapro
@@ -13,6 +13,9 @@ Supported adapters:
* VIA Technologies, Inc. VT8235, VT8237R, VT8237A, VT8251
Datasheet: available on request and under NDA from VIA
+ * VIA Technologies, Inc. CX700
+ Datasheet: available on request and under NDA from VIA
+
Authors:
Kyösti Mälkki <kmalkki@cc.hut.fi>,
Mark D. Studebaker <mdsxyz123@yahoo.com>,
@@ -44,6 +47,7 @@ Your lspci -n listing must show one of these :
device 1106:3227 (VT8237R)
device 1106:3337 (VT8237A)
device 1106:3287 (VT8251)
+ device 1106:8324 (CX700)
If none of these show up, you should look in the BIOS for settings like
enable ACPI / SMBus or even USB.
@@ -51,3 +55,6 @@ enable ACPI / SMBus or even USB.
Except for the oldest chips (VT82C596A/B, VT82C686A and most probably
VT8231), this driver supports I2C block transactions. Such transactions
are mainly useful to read from and write to EEPROMs.
+
+The CX700 additionally appears to support SMBus PEC, although this driver
+doesn't implement it yet.