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authorLinus Torvalds <torvalds@linux-foundation.org>2010-03-03 07:34:47 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2010-03-03 07:34:47 -0800
commita03696e912cd544e1504a79e49600cdb535f42db (patch)
tree7a9357153c3479f103cf74ea90ce4a5c983b0f2d /Documentation
parent0a135ba14d71fb84c691a5386aff5049691fe6d7 (diff)
parent0c43ea544c1086fbbed5a6c99ea58eb64674ea8f (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: Document the message size limit i2c-algo-pca: Drop duplicate variable i2c: Hook up runtime PM support i2c-parport-light: Add SMBus alert support i2c-parport: Add SMBus alert support i2c: Separate Kconfig option for i2c-smbus i2c: Add SMBus alert support i2c-parport: Give powered devices some time to settle i2c-tiny-usb: Fix a comment on bus frequency i2c-i801: Add Intel Cougar Point device IDs i2c: Make PCI device ids constant
Diffstat (limited to 'Documentation')
-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/smbus-protocol16
-rw-r--r--Documentation/i2c/writing-clients5
5 files changed, 35 insertions, 3 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:
* Intel 82801I (ICH9)
* Intel EP80579 (Tolapai)
* Intel 82801JI (ICH10)
- * Intel PCH
+ * Intel 3400/5 Series (PCH)
+ * Intel Cougar Point (PCH)
Datasheets: Publicly available at the Intel website
Authors:
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.
Earlier kernels defaulted to type=0 (Philips). But now, if the type
parameter is missing, the driver will simply fail to initialize.
+SMBus alert support is available on adapters which have this line properly
+connected to the parallel port's interrupt pin.
+
Building your own adapter
-------------------------
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
and the impossibility to daisy-chain other parallel port devices.
Please see i2c-parport for documentation.
+
+Module parameters:
+
+* type: type of adapter (see i2c-parport or modinfo)
+
+* base: base I/O address
+ Default is 0x378 which is fairly common for parallel ports, at least on PC.
+
+* irq: optional IRQ
+ This must be passed if you want SMBus alert support, assuming your adapter
+ actually supports this.
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
require PEC checksums.
+SMBus Alert
+===========
+
+SMBus Alert was introduced in Revision 1.0 of the specification.
+
+The SMBus alert protocol allows several SMBus slave devices to share a
+single interrupt pin on the SMBus master, while still allowing the master
+to know which slave triggered the interrupt.
+
+This is implemented the following way in the Linux kernel:
+* I2C bus drivers which support SMBus alert should call
+ i2c_setup_smbus_alert() to setup SMBus alert support.
+* I2C drivers for devices which can trigger SMBus alerts should implement
+ the optional alert() callback.
+
+
I2C Block Transactions
======================
diff --git a/Documentation/i2c/writing-clients b/Documentation/i2c/writing-clients
index 0a74603eb671..3219ee0dbfef 100644
--- a/Documentation/i2c/writing-clients
+++ b/Documentation/i2c/writing-clients
@@ -318,8 +318,9 @@ Plain I2C communication
These routines read and write some bytes from/to a client. The client
contains the i2c address, so you do not have to include it. The second
parameter contains the bytes to read/write, the third the number of bytes
-to read/write (must be less than the length of the buffer.) Returned is
-the actual number of bytes read/written.
+to read/write (must be less than the length of the buffer, also should be
+less than 64k since msg.len is u16.) Returned is the actual number of bytes
+read/written.
int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msg,
int num);