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authorLinus Torvalds <torvalds@woody.linux-foundation.org>2007-07-12 13:25:00 -0700
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-07-12 13:25:00 -0700
commit068345f4a873e8b0b511e8f94a595a20e176eeff (patch)
treef67503164f017b45ab425827d71fb7d23920a519 /Documentation
parentc39736823232bc3ca113c8228fa852c09fba300e (diff)
parent0a85e9a271a754e352af8a8b625025017fd97449 (diff)
Merge branch 'i2c-for-linus' of git://jdelvare.pck.nerim.net/jdelvare-2.6
* 'i2c-for-linus' of git://jdelvare.pck.nerim.net/jdelvare-2.6: (26 commits) i2c-rpx: Remove i2c-mpc: work around missing-9th-clock-pulse bug i2c: New PMC MSP71xx TWI bus driver i2c-savage4: Delete many unused defines i2c/tsl2550: Speed up initialization i2c: New bus driver for the TAOS evaluation modules i2c-i801: Use the internal 32-byte buffer on ICH4+ i2c-i801: Various cleanups i2c: Add support for the TSL2550 i2c-pxa: Support new-style I2C drivers i2c-gpio: Make some internal functions static i2c-gpio: Add support for new-style clients i2c-iop3xx: Switch to static adapter numbering i2c-sis5595: Resolve resource conflict with sis5595 matroxfb: Clean-up i2c header inclusions i2c-nforce2: Add support for SMBus block transactions i2c-mpc: Use i2c_add_numbered_adapter i2c-mv64xxx: Use i2c_add_numbered_adapter i2c-piix4: Add support for the ATI SB700 i2c: New DS1682 chip driver ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/DocBook/kernel-api.tmpl55
-rw-r--r--Documentation/feature-removal-schedule.txt7
-rw-r--r--Documentation/i2c/busses/i2c-i8014
-rw-r--r--Documentation/i2c/busses/i2c-piix42
-rw-r--r--Documentation/i2c/busses/i2c-taos-evm46
-rw-r--r--Documentation/i2c/chips/max68752
-rw-r--r--Documentation/i2c/chips/x120538
-rw-r--r--Documentation/i2c/summary2
-rw-r--r--Documentation/i2c/writing-clients2
9 files changed, 113 insertions, 45 deletions
diff --git a/Documentation/DocBook/kernel-api.tmpl b/Documentation/DocBook/kernel-api.tmpl
index 8c5698a8c2e1..46bcff2849bd 100644
--- a/Documentation/DocBook/kernel-api.tmpl
+++ b/Documentation/DocBook/kernel-api.tmpl
@@ -643,6 +643,60 @@ X!Idrivers/video/console/fonts.c
!Edrivers/spi/spi.c
</chapter>
+ <chapter id="i2c">
+ <title>I<superscript>2</superscript>C and SMBus Subsystem</title>
+
+ <para>
+ I<superscript>2</superscript>C (or without fancy typography, "I2C")
+ is an acronym for the "Inter-IC" bus, a simple bus protocol which is
+ widely used where low data rate communications suffice.
+ Since it's also a licensed trademark, some vendors use another
+ name (such as "Two-Wire Interface", TWI) for the same bus.
+ I2C only needs two signals (SCL for clock, SDA for data), conserving
+ board real estate and minimizing signal quality issues.
+ Most I2C devices use seven bit addresses, and bus speeds of up
+ to 400 kHz; there's a high speed extension (3.4 MHz) that's not yet
+ found wide use.
+ I2C is a multi-master bus; open drain signaling is used to
+ arbitrate between masters, as well as to handshake and to
+ synchronize clocks from slower clients.
+ </para>
+
+ <para>
+ The Linux I2C programming interfaces support only the master
+ side of bus interactions, not the slave side.
+ The programming interface is structured around two kinds of driver,
+ and two kinds of device.
+ An I2C "Adapter Driver" abstracts the controller hardware; it binds
+ to a physical device (perhaps a PCI device or platform_device) and
+ exposes a <structname>struct i2c_adapter</structname> representing
+ each I2C bus segment it manages.
+ On each I2C bus segment will be I2C devices represented by a
+ <structname>struct i2c_client</structname>. Those devices will
+ be bound to a <structname>struct i2c_driver</structname>,
+ which should follow the standard Linux driver model.
+ (At this writing, a legacy model is more widely used.)
+ There are functions to perform various I2C protocol operations; at
+ this writing all such functions are usable only from task context.
+ </para>
+
+ <para>
+ The System Management Bus (SMBus) is a sibling protocol. Most SMBus
+ systems are also I2C conformant. The electrical constraints are
+ tighter for SMBus, and it standardizes particular protocol messages
+ and idioms. Controllers that support I2C can also support most
+ SMBus operations, but SMBus controllers don't support all the protocol
+ options that an I2C controller will.
+ There are functions to perform various SMBus protocol operations,
+ either using I2C primitives or by issuing SMBus commands to
+ i2c_adapter devices which don't support those I2C operations.
+ </para>
+
+!Iinclude/linux/i2c.h
+!Fdrivers/i2c/i2c-boardinfo.c i2c_register_board_info
+!Edrivers/i2c/i2c-core.c
+ </chapter>
+
<chapter id="splice">
<title>splice API</title>
<para>)
@@ -654,4 +708,5 @@ X!Idrivers/video/console/fonts.c
!Ffs/splice.c
</chapter>
+
</book>
diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
index 3a159dac04f5..281458b47d75 100644
--- a/Documentation/feature-removal-schedule.txt
+++ b/Documentation/feature-removal-schedule.txt
@@ -330,3 +330,10 @@ Who: Tejun Heo <htejun@gmail.com>
---------------------------
+What: Legacy RTC drivers (under drivers/i2c/chips)
+When: November 2007
+Why: Obsolete. We have a RTC subsystem with better drivers.
+Who: Jean Delvare <khali@linux-fr.org>
+
+---------------------------
+
diff --git a/Documentation/i2c/busses/i2c-i801 b/Documentation/i2c/busses/i2c-i801
index c34f0db78a30..fe6406f2f9a6 100644
--- a/Documentation/i2c/busses/i2c-i801
+++ b/Documentation/i2c/busses/i2c-i801
@@ -5,8 +5,8 @@ Supported adapters:
'810' and '810E' chipsets)
* Intel 82801BA (ICH2 - part of the '815E' chipset)
* Intel 82801CA/CAM (ICH3)
- * Intel 82801DB (ICH4) (HW PEC supported, 32 byte buffer not supported)
- * Intel 82801EB/ER (ICH5) (HW PEC supported, 32 byte buffer not supported)
+ * Intel 82801DB (ICH4) (HW PEC supported)
+ * Intel 82801EB/ER (ICH5) (HW PEC supported)
* Intel 6300ESB
* Intel 82801FB/FR/FW/FRW (ICH6)
* Intel 82801G (ICH7)
diff --git a/Documentation/i2c/busses/i2c-piix4 b/Documentation/i2c/busses/i2c-piix4
index 7cbe43fa2701..fa0c786a8bf5 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 IXP200, IXP300, IXP400 and SB600 southbridges
+ * ATI IXP200, IXP300, IXP400, SB600 and SB700 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-taos-evm b/Documentation/i2c/busses/i2c-taos-evm
new file mode 100644
index 000000000000..9146e33be6dd
--- /dev/null
+++ b/Documentation/i2c/busses/i2c-taos-evm
@@ -0,0 +1,46 @@
+Kernel driver i2c-taos-evm
+
+Author: Jean Delvare <khali@linux-fr.org>
+
+This is a driver for the evaluation modules for TAOS I2C/SMBus chips.
+The modules include an SMBus master with limited capabilities, which can
+be controlled over the serial port. Virtually all evaluation modules
+are supported, but a few lines of code need to be added for each new
+module to instantiate the right I2C chip on the bus. Obviously, a driver
+for the chip in question is also needed.
+
+Currently supported devices are:
+
+* TAOS TSL2550 EVM
+
+For addtional information on TAOS products, please see
+ http://www.taosinc.com/
+
+
+Using this driver
+-----------------
+
+In order to use this driver, you'll need the serport driver, and the
+inputattach tool, which is part of the input-utils package. The following
+commands will tell the kernel that you have a TAOS EVM on the first
+serial port:
+
+# modprobe serport
+# inputattach --taos-evm /dev/ttyS0
+
+
+Technical details
+-----------------
+
+Only 4 SMBus transaction types are supported by the TAOS evaluation
+modules:
+* Receive Byte
+* Send Byte
+* Read Byte
+* Write Byte
+
+The communication protocol is text-based and pretty simple. It is
+described in a PDF document on the CD which comes with the evaluation
+module. The communication is rather slow, because the serial port has
+to operate at 1200 bps. However, I don't think this is a big concern in
+practice, as these modules are meant for evaluation and testing only.
diff --git a/Documentation/i2c/chips/max6875 b/Documentation/i2c/chips/max6875
index 96fec562a8e9..a0cd8af2f408 100644
--- a/Documentation/i2c/chips/max6875
+++ b/Documentation/i2c/chips/max6875
@@ -99,7 +99,7 @@ And then read the data
or
- count = i2c_smbus_read_i2c_block_data(fd, 0x84, buffer);
+ count = i2c_smbus_read_i2c_block_data(fd, 0x84, 16, buffer);
The block read should read 16 bytes.
0x84 is the block read command.
diff --git a/Documentation/i2c/chips/x1205 b/Documentation/i2c/chips/x1205
deleted file mode 100644
index 09407c991fe5..000000000000
--- a/Documentation/i2c/chips/x1205
+++ /dev/null
@@ -1,38 +0,0 @@
-Kernel driver x1205
-===================
-
-Supported chips:
- * Xicor X1205 RTC
- Prefix: 'x1205'
- Addresses scanned: none
- Datasheet: http://www.intersil.com/cda/deviceinfo/0,1477,X1205,00.html
-
-Authors:
- Karen Spearel <kas11@tampabay.rr.com>,
- Alessandro Zummo <a.zummo@towertech.it>
-
-Description
------------
-
-This module aims to provide complete access to the Xicor X1205 RTC.
-Recently Xicor has merged with Intersil, but the chip is
-still sold under the Xicor brand.
-
-This chip is located at address 0x6f and uses a 2-byte register addressing.
-Two bytes need to be written to read a single register, while most
-other chips just require one and take the second one as the data
-to be written. To prevent corrupting unknown chips, the user must
-explicitely set the probe parameter.
-
-example:
-
-modprobe x1205 probe=0,0x6f
-
-The module supports one more option, hctosys, which is used to set the
-software clock from the x1205. On systems where the x1205 is the
-only hardware rtc, this parameter could be used to achieve a correct
-date/time earlier in the system boot sequence.
-
-example:
-
-modprobe x1205 probe=0,0x6f hctosys=1
diff --git a/Documentation/i2c/summary b/Documentation/i2c/summary
index aea60bf7e8f0..003c7319b8c7 100644
--- a/Documentation/i2c/summary
+++ b/Documentation/i2c/summary
@@ -67,7 +67,6 @@ i2c-proc: The /proc/sys/dev/sensors interface for device (client) drivers
Algorithm drivers
-----------------
-i2c-algo-8xx: An algorithm for CPM's I2C device in Motorola 8xx processors (NOT BUILT BY DEFAULT)
i2c-algo-bit: A bit-banging algorithm
i2c-algo-pcf: A PCF 8584 style algorithm
i2c-algo-ibm_ocp: An algorithm for the I2C device in IBM 4xx processors (NOT BUILT BY DEFAULT)
@@ -81,6 +80,5 @@ i2c-pcf-epp: PCF8584 on a EPP parallel port (uses i2c-algo-pcf) (NOT mkpatch
i2c-philips-par: Philips style parallel port adapter (uses i2c-algo-bit)
i2c-adap-ibm_ocp: IBM 4xx processor I2C device (uses i2c-algo-ibm_ocp) (NOT BUILT BY DEFAULT)
i2c-pport: Primitive parallel port adapter (uses i2c-algo-bit)
-i2c-rpx: RPX board Motorola 8xx I2C device (uses i2c-algo-8xx) (NOT BUILT BY DEFAULT)
i2c-velleman: Velleman K8000 parallel port adapter (uses i2c-algo-bit)
diff --git a/Documentation/i2c/writing-clients b/Documentation/i2c/writing-clients
index 3d8d36b0ad12..2c170032bf37 100644
--- a/Documentation/i2c/writing-clients
+++ b/Documentation/i2c/writing-clients
@@ -571,7 +571,7 @@ SMBus communication
u8 command, u8 length,
u8 *values);
extern s32 i2c_smbus_read_i2c_block_data(struct i2c_client * client,
- u8 command, u8 *values);
+ u8 command, u8 length, u8 *values);
These ones were removed in Linux 2.6.10 because they had no users, but could
be added back later if needed: