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-rw-r--r--Documentation/i2c/busses/i2c-i8013
-rw-r--r--Documentation/i2c/busses/i2c-nforce22
-rw-r--r--Documentation/i2c/busses/i2c-ocores51
-rw-r--r--Documentation/i2c/busses/i2c-piix440
-rw-r--r--Documentation/i2c/busses/scx200_acb19
5 files changed, 105 insertions, 10 deletions
diff --git a/Documentation/i2c/busses/i2c-i801 b/Documentation/i2c/busses/i2c-i801
index fd4b2712d57..e46c2345824 100644
--- a/Documentation/i2c/busses/i2c-i801
+++ b/Documentation/i2c/busses/i2c-i801
@@ -21,8 +21,7 @@ Authors:
Module Parameters
-----------------
-* force_addr: int
- Forcibly enable the ICH at the given address. EXTREMELY DANGEROUS!
+None.
Description
diff --git a/Documentation/i2c/busses/i2c-nforce2 b/Documentation/i2c/busses/i2c-nforce2
index d751282d9b2..cd49c428a3a 100644
--- a/Documentation/i2c/busses/i2c-nforce2
+++ b/Documentation/i2c/busses/i2c-nforce2
@@ -7,6 +7,8 @@ Supported adapters:
* nForce3 250Gb MCP 10de:00E4
* nForce4 MCP 10de:0052
* nForce4 MCP-04 10de:0034
+ * nForce4 MCP51 10de:0264
+ * nForce4 MCP55 10de:0368
Datasheet: not publically available, but seems to be similar to the
AMD-8111 SMBus 2.0 adapter.
diff --git a/Documentation/i2c/busses/i2c-ocores b/Documentation/i2c/busses/i2c-ocores
new file mode 100644
index 00000000000..cfcebb10d14
--- /dev/null
+++ b/Documentation/i2c/busses/i2c-ocores
@@ -0,0 +1,51 @@
+Kernel driver i2c-ocores
+
+Supported adapters:
+ * OpenCores.org I2C controller by Richard Herveille (see datasheet link)
+ Datasheet: http://www.opencores.org/projects.cgi/web/i2c/overview
+
+Author: Peter Korsgaard <jacmet@sunsite.dk>
+
+Description
+-----------
+
+i2c-ocores is an i2c bus driver for the OpenCores.org I2C controller
+IP core by Richard Herveille.
+
+Usage
+-----
+
+i2c-ocores uses the platform bus, so you need to provide a struct
+platform_device with the base address and interrupt number. The
+dev.platform_data of the device should also point to a struct
+ocores_i2c_platform_data (see linux/i2c-ocores.h) describing the
+distance between registers and the input clock speed.
+
+E.G. something like:
+
+static struct resource ocores_resources[] = {
+ [0] = {
+ .start = MYI2C_BASEADDR,
+ .end = MYI2C_BASEADDR + 8,
+ .flags = IORESOURCE_MEM,
+ },
+ [1] = {
+ .start = MYI2C_IRQ,
+ .end = MYI2C_IRQ,
+ .flags = IORESOURCE_IRQ,
+ },
+};
+
+static struct ocores_i2c_platform_data myi2c_data = {
+ .regstep = 2, /* two bytes between registers */
+ .clock_khz = 50000, /* input clock of 50MHz */
+};
+
+static struct platform_device myi2c = {
+ .name = "ocores-i2c",
+ .dev = {
+ .platform_data = &myi2c_data,
+ },
+ .num_resources = ARRAY_SIZE(ocores_resources),
+ .resource = ocores_resources,
+};
diff --git a/Documentation/i2c/busses/i2c-piix4 b/Documentation/i2c/busses/i2c-piix4
index a1c8f581afe..92147633323 100644
--- a/Documentation/i2c/busses/i2c-piix4
+++ b/Documentation/i2c/busses/i2c-piix4
@@ -6,6 +6,8 @@ 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
+ Datasheet: Not publicly available
* Standard Microsystems (SMSC) SLC90E66 (Victory66) southbridge
Datasheet: Publicly available at the SMSC website http://www.smsc.com
@@ -21,8 +23,6 @@ Module Parameters
Forcibly enable the PIIX4. DANGEROUS!
* force_addr: int
Forcibly enable the PIIX4 at the given address. EXTREMELY DANGEROUS!
-* fix_hstcfg: int
- Fix config register. Needed on some boards (Force CPCI735).
Description
@@ -63,10 +63,36 @@ The PIIX4E is just an new version of the PIIX4; it is supported as well.
The PIIX/PIIX3 does not implement an SMBus or I2C bus, so you can't use
this driver on those mainboards.
-The ServerWorks Southbridges, the Intel 440MX, and the Victory766 are
+The ServerWorks Southbridges, the Intel 440MX, and the Victory66 are
identical to the PIIX4 in I2C/SMBus support.
-A few OSB4 southbridges are known to be misconfigured by the BIOS. In this
-case, you have you use the fix_hstcfg module parameter. Do not use it
-unless you know you have to, because in some cases it also breaks
-configuration on southbridges that don't need it.
+If you own Force CPCI735 motherboard or other OSB4 based systems you may need
+to change the SMBus Interrupt Select register so the SMBus controller uses
+the SMI mode.
+
+1) Use lspci command and locate the PCI device with the SMBus controller:
+ 00:0f.0 ISA bridge: ServerWorks OSB4 South Bridge (rev 4f)
+ The line may vary for different chipsets. Please consult the driver source
+ for all possible PCI ids (and lspci -n to match them). Lets assume the
+ device is located at 00:0f.0.
+2) Now you just need to change the value in 0xD2 register. Get it first with
+ command: lspci -xxx -s 00:0f.0
+ If the value is 0x3 then you need to change it to 0x1
+ setpci -s 00:0f.0 d2.b=1
+
+Please note that you don't need to do that in all cases, just when the SMBus is
+not working properly.
+
+
+Hardware-specific issues
+------------------------
+
+This driver will refuse to load on IBM systems with an Intel PIIX4 SMBus.
+Some of these machines have an RFID EEPROM (24RF08) connected to the SMBus,
+which can easily get corrupted due to a state machine bug. These are mostly
+Thinkpad laptops, but desktop systems may also be affected. We have no list
+of all affected systems, so the only safe solution was to prevent access to
+the SMBus on all IBM systems (detected using DMI data.)
+
+For additional information, read:
+http://www2.lm-sensors.nu/~lm78/cvs/lm_sensors2/README.thinkpad
diff --git a/Documentation/i2c/busses/scx200_acb b/Documentation/i2c/busses/scx200_acb
index f50e69981ec..7c07883d4df 100644
--- a/Documentation/i2c/busses/scx200_acb
+++ b/Documentation/i2c/busses/scx200_acb
@@ -2,14 +2,31 @@ Kernel driver scx200_acb
Author: Christer Weinigel <wingel@nano-system.com>
+The driver supersedes the older, never merged driver named i2c-nscacb.
+
Module Parameters
-----------------
-* base: int
+* base: up to 4 ints
Base addresses for the ACCESS.bus controllers on SCx200 and SC1100 devices
+ By default the driver uses two base addresses 0x820 and 0x840.
+ If you want only one base address, specify the second as 0 so as to
+ override this default.
+
Description
-----------
Enable the use of the ACCESS.bus controller on the Geode SCx200 and
SC1100 processors and the CS5535 and CS5536 Geode companion devices.
+
+Device-specific notes
+---------------------
+
+The SC1100 WRAP boards are known to use base addresses 0x810 and 0x820.
+If the scx200_acb driver is built into the kernel, add the following
+parameter to your boot command line:
+ scx200_acb.base=0x810,0x820
+If the scx200_acb driver is built as a module, add the following line to
+the file /etc/modprobe.conf instead:
+ options scx200_acb base=0x810,0x820