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authorSage Weil <sage@inktank.com>2012-06-15 12:32:04 -0700
committerSage Weil <sage@inktank.com>2012-06-15 12:32:04 -0700
commit9a64e8e0ace51b309fdcff4b4754b3649250382a (patch)
tree1f0d75c196c5ab0408c55ed6cf3a152f1f921e15 /Documentation/i2c
parentf3dea7edd3d449fe7a6d402c1ce56a294b985261 (diff)
parentf8f5701bdaf9134b1f90e5044a82c66324d2073f (diff)
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Merge tag 'v3.5-rc1'
Linux 3.5-rc1 Conflicts: net/ceph/messenger.c
Diffstat (limited to 'Documentation/i2c')
-rw-r--r--Documentation/i2c/busses/i2c-i8011
-rw-r--r--Documentation/i2c/busses/scx200_acb2
-rw-r--r--Documentation/i2c/functionality9
-rw-r--r--Documentation/i2c/i2c-protocol9
-rw-r--r--Documentation/i2c/instantiating-devices6
-rw-r--r--Documentation/i2c/muxes/i2c-mux-gpio (renamed from Documentation/i2c/muxes/gpio-i2cmux)12
6 files changed, 25 insertions, 14 deletions
diff --git a/Documentation/i2c/busses/i2c-i801 b/Documentation/i2c/busses/i2c-i801
index 2871fd500349..71f55bbcefc8 100644
--- a/Documentation/i2c/busses/i2c-i801
+++ b/Documentation/i2c/busses/i2c-i801
@@ -20,6 +20,7 @@ Supported adapters:
* Intel Patsburg (PCH)
* Intel DH89xxCC (PCH)
* Intel Panther Point (PCH)
+ * Intel Lynx Point (PCH)
Datasheets: Publicly available at the Intel website
On Intel Patsburg and later chipsets, both the normal host SMBus controller
diff --git a/Documentation/i2c/busses/scx200_acb b/Documentation/i2c/busses/scx200_acb
index 7c07883d4dfc..ce83c871fe95 100644
--- a/Documentation/i2c/busses/scx200_acb
+++ b/Documentation/i2c/busses/scx200_acb
@@ -28,5 +28,5 @@ 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:
+a configuration file in /etc/modprobe.d/ instead:
options scx200_acb base=0x810,0x820
diff --git a/Documentation/i2c/functionality b/Documentation/i2c/functionality
index 42c17c1fb3cd..b0ff2ab596ce 100644
--- a/Documentation/i2c/functionality
+++ b/Documentation/i2c/functionality
@@ -18,9 +18,9 @@ For the most up-to-date list of functionality constants, please check
adapters typically can not do these)
I2C_FUNC_10BIT_ADDR Handles the 10-bit address extensions
I2C_FUNC_PROTOCOL_MANGLING Knows about the I2C_M_IGNORE_NAK,
- I2C_M_REV_DIR_ADDR, I2C_M_NOSTART and
- I2C_M_NO_RD_ACK flags (which modify the
- I2C protocol!)
+ I2C_M_REV_DIR_ADDR and I2C_M_NO_RD_ACK
+ flags (which modify the I2C protocol!)
+ I2C_FUNC_NOSTART Can skip repeated start sequence
I2C_FUNC_SMBUS_QUICK Handles the SMBus write_quick command
I2C_FUNC_SMBUS_READ_BYTE Handles the SMBus read_byte command
I2C_FUNC_SMBUS_WRITE_BYTE Handles the SMBus write_byte command
@@ -50,6 +50,9 @@ A few combinations of the above flags are also defined for your convenience:
emulated by a real I2C adapter (using
the transparent emulation layer)
+In kernel versions prior to 3.5 I2C_FUNC_NOSTART was implemented as
+part of I2C_FUNC_PROTOCOL_MANGLING.
+
ADAPTER IMPLEMENTATION
----------------------
diff --git a/Documentation/i2c/i2c-protocol b/Documentation/i2c/i2c-protocol
index 10518dd58814..0b3e62d1f77a 100644
--- a/Documentation/i2c/i2c-protocol
+++ b/Documentation/i2c/i2c-protocol
@@ -49,7 +49,9 @@ a byte read, followed by a byte write:
Modified transactions
=====================
-We have found some I2C devices that needs the following modifications:
+The following modifications to the I2C protocol can also be generated,
+with the exception of I2C_M_NOSTART these are usually only needed to
+work around device issues:
Flag I2C_M_NOSTART:
In a combined transaction, no 'S Addr Wr/Rd [A]' is generated at some
@@ -60,6 +62,11 @@ We have found some I2C devices that needs the following modifications:
we do not generate Addr, but we do generate the startbit S. This will
probably confuse all other clients on your bus, so don't try this.
+ This is often used to gather transmits from multiple data buffers in
+ system memory into something that appears as a single transfer to the
+ I2C device but may also be used between direction changes by some
+ rare devices.
+
Flags I2C_M_REV_DIR_ADDR
This toggles the Rd/Wr flag. That is, if you want to do a write, but
need to emit an Rd instead of a Wr, or vice versa, you set this
diff --git a/Documentation/i2c/instantiating-devices b/Documentation/i2c/instantiating-devices
index 9edb75d8c9b9..abf63615ee05 100644
--- a/Documentation/i2c/instantiating-devices
+++ b/Documentation/i2c/instantiating-devices
@@ -87,11 +87,11 @@ it may have different addresses from one board to the next (manufacturer
changing its design without notice). In this case, you can call
i2c_new_probed_device() instead of i2c_new_device().
-Example (from the pnx4008 OHCI driver):
+Example (from the nxp OHCI driver):
static const unsigned short normal_i2c[] = { 0x2c, 0x2d, I2C_CLIENT_END };
-static int __devinit usb_hcd_pnx4008_probe(struct platform_device *pdev)
+static int __devinit usb_hcd_nxp_probe(struct platform_device *pdev)
{
(...)
struct i2c_adapter *i2c_adap;
@@ -100,7 +100,7 @@ static int __devinit usb_hcd_pnx4008_probe(struct platform_device *pdev)
(...)
i2c_adap = i2c_get_adapter(2);
memset(&i2c_info, 0, sizeof(struct i2c_board_info));
- strlcpy(i2c_info.type, "isp1301_pnx", I2C_NAME_SIZE);
+ strlcpy(i2c_info.type, "isp1301_nxp", I2C_NAME_SIZE);
isp1301_i2c_client = i2c_new_probed_device(i2c_adap, &i2c_info,
normal_i2c, NULL);
i2c_put_adapter(i2c_adap);
diff --git a/Documentation/i2c/muxes/gpio-i2cmux b/Documentation/i2c/muxes/i2c-mux-gpio
index 811cd78d4cdc..bd9b2299b739 100644
--- a/Documentation/i2c/muxes/gpio-i2cmux
+++ b/Documentation/i2c/muxes/i2c-mux-gpio
@@ -1,11 +1,11 @@
-Kernel driver gpio-i2cmux
+Kernel driver i2c-gpio-mux
Author: Peter Korsgaard <peter.korsgaard@barco.com>
Description
-----------
-gpio-i2cmux is an i2c mux driver providing access to I2C bus segments
+i2c-gpio-mux is an i2c mux driver providing access to I2C bus segments
from a master I2C bus and a hardware MUX controlled through GPIO pins.
E.G.:
@@ -26,16 +26,16 @@ according to the settings of the GPIO pins 1..N.
Usage
-----
-gpio-i2cmux uses the platform bus, so you need to provide a struct
+i2c-gpio-mux uses the platform bus, so you need to provide a struct
platform_device with the platform_data pointing to a struct
gpio_i2cmux_platform_data with the I2C adapter number of the master
bus, the number of bus segments to create and the GPIO pins used
-to control it. See include/linux/gpio-i2cmux.h for details.
+to control it. See include/linux/i2c-gpio-mux.h for details.
E.G. something like this for a MUX providing 4 bus segments
controlled through 3 GPIO pins:
-#include <linux/gpio-i2cmux.h>
+#include <linux/i2c-gpio-mux.h>
#include <linux/platform_device.h>
static const unsigned myboard_gpiomux_gpios[] = {
@@ -57,7 +57,7 @@ static struct gpio_i2cmux_platform_data myboard_i2cmux_data = {
};
static struct platform_device myboard_i2cmux = {
- .name = "gpio-i2cmux",
+ .name = "i2c-gpio-mux",
.id = 0,
.dev = {
.platform_data = &myboard_i2cmux_data,