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-rw-r--r--Documentation/arm/OMAP/omap_pm129
-rw-r--r--Documentation/cpu-freq/user-guide.txt9
-rw-r--r--Documentation/filesystems/ext4.txt24
-rw-r--r--Documentation/hwmon/wm831x37
-rw-r--r--Documentation/hwmon/wm835026
-rw-r--r--Documentation/kernel-doc-nano-HOWTO.txt4
-rw-r--r--Documentation/kernel-parameters.txt2
-rw-r--r--Documentation/kref.txt1
-rw-r--r--Documentation/x86/boot.txt1
9 files changed, 217 insertions, 16 deletions
diff --git a/Documentation/arm/OMAP/omap_pm b/Documentation/arm/OMAP/omap_pm
new file mode 100644
index 00000000000..5389440aade
--- /dev/null
+++ b/Documentation/arm/OMAP/omap_pm
@@ -0,0 +1,129 @@
+
+The OMAP PM interface
+=====================
+
+This document describes the temporary OMAP PM interface. Driver
+authors use these functions to communicate minimum latency or
+throughput constraints to the kernel power management code.
+Over time, the intention is to merge features from the OMAP PM
+interface into the Linux PM QoS code.
+
+Drivers need to express PM parameters which:
+
+- support the range of power management parameters present in the TI SRF;
+
+- separate the drivers from the underlying PM parameter
+ implementation, whether it is the TI SRF or Linux PM QoS or Linux
+ latency framework or something else;
+
+- specify PM parameters in terms of fundamental units, such as
+ latency and throughput, rather than units which are specific to OMAP
+ or to particular OMAP variants;
+
+- allow drivers which are shared with other architectures (e.g.,
+ DaVinci) to add these constraints in a way which won't affect non-OMAP
+ systems,
+
+- can be implemented immediately with minimal disruption of other
+ architectures.
+
+
+This document proposes the OMAP PM interface, including the following
+five power management functions for driver code:
+
+1. Set the maximum MPU wakeup latency:
+ (*pdata->set_max_mpu_wakeup_lat)(struct device *dev, unsigned long t)
+
+2. Set the maximum device wakeup latency:
+ (*pdata->set_max_dev_wakeup_lat)(struct device *dev, unsigned long t)
+
+3. Set the maximum system DMA transfer start latency (CORE pwrdm):
+ (*pdata->set_max_sdma_lat)(struct device *dev, long t)
+
+4. Set the minimum bus throughput needed by a device:
+ (*pdata->set_min_bus_tput)(struct device *dev, u8 agent_id, unsigned long r)
+
+5. Return the number of times the device has lost context
+ (*pdata->get_dev_context_loss_count)(struct device *dev)
+
+
+Further documentation for all OMAP PM interface functions can be
+found in arch/arm/plat-omap/include/mach/omap-pm.h.
+
+
+The OMAP PM layer is intended to be temporary
+---------------------------------------------
+
+The intention is that eventually the Linux PM QoS layer should support
+the range of power management features present in OMAP3. As this
+happens, existing drivers using the OMAP PM interface can be modified
+to use the Linux PM QoS code; and the OMAP PM interface can disappear.
+
+
+Driver usage of the OMAP PM functions
+-------------------------------------
+
+As the 'pdata' in the above examples indicates, these functions are
+exposed to drivers through function pointers in driver .platform_data
+structures. The function pointers are initialized by the board-*.c
+files to point to the corresponding OMAP PM functions:
+.set_max_dev_wakeup_lat will point to
+omap_pm_set_max_dev_wakeup_lat(), etc. Other architectures which do
+not support these functions should leave these function pointers set
+to NULL. Drivers should use the following idiom:
+
+ if (pdata->set_max_dev_wakeup_lat)
+ (*pdata->set_max_dev_wakeup_lat)(dev, t);
+
+The most common usage of these functions will probably be to specify
+the maximum time from when an interrupt occurs, to when the device
+becomes accessible. To accomplish this, driver writers should use the
+set_max_mpu_wakeup_lat() function to to constrain the MPU wakeup
+latency, and the set_max_dev_wakeup_lat() function to constrain the
+device wakeup latency (from clk_enable() to accessibility). For
+example,
+
+ /* Limit MPU wakeup latency */
+ if (pdata->set_max_mpu_wakeup_lat)
+ (*pdata->set_max_mpu_wakeup_lat)(dev, tc);
+
+ /* Limit device powerdomain wakeup latency */
+ if (pdata->set_max_dev_wakeup_lat)
+ (*pdata->set_max_dev_wakeup_lat)(dev, td);
+
+ /* total wakeup latency in this example: (tc + td) */
+
+The PM parameters can be overwritten by calling the function again
+with the new value. The settings can be removed by calling the
+function with a t argument of -1 (except in the case of
+set_max_bus_tput(), which should be called with an r argument of 0).
+
+The fifth function above, omap_pm_get_dev_context_loss_count(),
+is intended as an optimization to allow drivers to determine whether the
+device has lost its internal context. If context has been lost, the
+driver must restore its internal context before proceeding.
+
+
+Other specialized interface functions
+-------------------------------------
+
+The five functions listed above are intended to be usable by any
+device driver. DSPBridge and CPUFreq have a few special requirements.
+DSPBridge expresses target DSP performance levels in terms of OPP IDs.
+CPUFreq expresses target MPU performance levels in terms of MPU
+frequency. The OMAP PM interface contains functions for these
+specialized cases to convert that input information (OPPs/MPU
+frequency) into the form that the underlying power management
+implementation needs:
+
+6. (*pdata->dsp_get_opp_table)(void)
+
+7. (*pdata->dsp_set_min_opp)(u8 opp_id)
+
+8. (*pdata->dsp_get_opp)(void)
+
+9. (*pdata->cpu_get_freq_table)(void)
+
+10. (*pdata->cpu_set_freq)(unsigned long f)
+
+11. (*pdata->cpu_get_freq)(void)
diff --git a/Documentation/cpu-freq/user-guide.txt b/Documentation/cpu-freq/user-guide.txt
index 5d5f5fadd1c..2a5b850847c 100644
--- a/Documentation/cpu-freq/user-guide.txt
+++ b/Documentation/cpu-freq/user-guide.txt
@@ -176,7 +176,9 @@ scaling_governor, and by "echoing" the name of another
work on some specific architectures or
processors.
-cpuinfo_cur_freq : Current speed of the CPU, in KHz.
+cpuinfo_cur_freq : Current frequency of the CPU as obtained from
+ the hardware, in KHz. This is the frequency
+ the CPU actually runs at.
scaling_available_frequencies : List of available frequencies, in KHz.
@@ -196,7 +198,10 @@ related_cpus : List of CPUs that need some sort of frequency
scaling_driver : Hardware driver for cpufreq.
-scaling_cur_freq : Current frequency of the CPU, in KHz.
+scaling_cur_freq : Current frequency of the CPU as determined by
+ the governor and cpufreq core, in KHz. This is
+ the frequency the kernel thinks the CPU runs
+ at.
If you have selected the "userspace" governor which allows you to
set the CPU operating frequency to a specific value, you can read out
diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt
index 7be02ac5fa3..18b5ec8cea4 100644
--- a/Documentation/filesystems/ext4.txt
+++ b/Documentation/filesystems/ext4.txt
@@ -134,15 +134,9 @@ ro Mount filesystem read only. Note that ext4 will
mount options "ro,noload" can be used to prevent
writes to the filesystem.
-journal_checksum Enable checksumming of the journal transactions.
- This will allow the recovery code in e2fsck and the
- kernel to detect corruption in the kernel. It is a
- compatible change and will be ignored by older kernels.
-
journal_async_commit Commit block can be written to disk without waiting
for descriptor blocks. If enabled older kernels cannot
- mount the device. This will enable 'journal_checksum'
- internally.
+ mount the device.
journal=update Update the ext4 file system's journal to the current
format.
@@ -263,10 +257,18 @@ resuid=n The user ID which may use the reserved blocks.
sb=n Use alternate superblock at this location.
-quota
-noquota
-grpquota
-usrquota
+quota These options are ignored by the filesystem. They
+noquota are used only by quota tools to recognize volumes
+grpquota where quota should be turned on. See documentation
+usrquota in the quota-tools package for more details
+ (http://sourceforge.net/projects/linuxquota).
+
+jqfmt=<quota type> These options tell filesystem details about quota
+usrjquota=<file> so that quota information can be properly updated
+grpjquota=<file> during journal replay. They replace the above
+ quota options. See documentation in the quota-tools
+ package for more details
+ (http://sourceforge.net/projects/linuxquota).
bh (*) ext4 associates buffer heads to data pages to
nobh (a) cache disk block mapping information
diff --git a/Documentation/hwmon/wm831x b/Documentation/hwmon/wm831x
new file mode 100644
index 00000000000..24f47d8f6a4
--- /dev/null
+++ b/Documentation/hwmon/wm831x
@@ -0,0 +1,37 @@
+Kernel driver wm831x-hwmon
+==========================
+
+Supported chips:
+ * Wolfson Microelectronics WM831x PMICs
+ Prefix: 'wm831x'
+ Datasheet:
+ http://www.wolfsonmicro.com/products/WM8310
+ http://www.wolfsonmicro.com/products/WM8311
+ http://www.wolfsonmicro.com/products/WM8312
+
+Authors: Mark Brown <broonie@opensource.wolfsonmicro.com>
+
+Description
+-----------
+
+The WM831x series of PMICs include an AUXADC which can be used to
+monitor a range of system operating parameters, including the voltages
+of the major supplies within the system. Currently the driver provides
+reporting of all the input values but does not provide any alarms.
+
+Voltage Monitoring
+------------------
+
+Voltages are sampled by a 12 bit ADC. Voltages in milivolts are 1.465
+times the ADC value.
+
+Temperature Monitoring
+----------------------
+
+Temperatures are sampled by a 12 bit ADC. Chip and battery temperatures
+are available. The chip temperature is calculated as:
+
+ Degrees celsius = (512.18 - data) / 1.0983
+
+while the battery temperature calculation will depend on the NTC
+thermistor component.
diff --git a/Documentation/hwmon/wm8350 b/Documentation/hwmon/wm8350
new file mode 100644
index 00000000000..98f923bd2e9
--- /dev/null
+++ b/Documentation/hwmon/wm8350
@@ -0,0 +1,26 @@
+Kernel driver wm8350-hwmon
+==========================
+
+Supported chips:
+ * Wolfson Microelectronics WM835x PMICs
+ Prefix: 'wm8350'
+ Datasheet:
+ http://www.wolfsonmicro.com/products/WM8350
+ http://www.wolfsonmicro.com/products/WM8351
+ http://www.wolfsonmicro.com/products/WM8352
+
+Authors: Mark Brown <broonie@opensource.wolfsonmicro.com>
+
+Description
+-----------
+
+The WM835x series of PMICs include an AUXADC which can be used to
+monitor a range of system operating parameters, including the voltages
+of the major supplies within the system. Currently the driver provides
+simple access to these major supplies.
+
+Voltage Monitoring
+------------------
+
+Voltages are sampled by a 12 bit ADC. For the internal supplies the ADC
+is referenced to the system VRTC.
diff --git a/Documentation/kernel-doc-nano-HOWTO.txt b/Documentation/kernel-doc-nano-HOWTO.txt
index 4d04572b654..348b9e5e28f 100644
--- a/Documentation/kernel-doc-nano-HOWTO.txt
+++ b/Documentation/kernel-doc-nano-HOWTO.txt
@@ -66,7 +66,9 @@ Example kernel-doc function comment:
* The longer description can have multiple paragraphs.
*/
-The first line, with the short description, must be on a single line.
+The short description following the subject can span multiple lines
+and ends with an @argument description, an empty line or the end of
+the comment block.
The @argument descriptions must begin on the very next line following
this opening short function description line, with no intervening
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index f45d0d8e71d..0f17d16dc10 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1565,7 +1565,7 @@ and is between 256 and 4096 characters. It is defined in the file
of returning the full 64-bit number.
The default is to return 64-bit inode numbers.
- nmi_debug= [KNL,AVR32] Specify one or more actions to take
+ nmi_debug= [KNL,AVR32,SH] Specify one or more actions to take
when a NMI is triggered.
Format: [state][,regs][,debounce][,die]
diff --git a/Documentation/kref.txt b/Documentation/kref.txt
index 130b6e87aa7..ae203f91ee9 100644
--- a/Documentation/kref.txt
+++ b/Documentation/kref.txt
@@ -84,7 +84,6 @@ int my_data_handler(void)
task = kthread_run(more_data_handling, data, "more_data_handling");
if (task == ERR_PTR(-ENOMEM)) {
rv = -ENOMEM;
- kref_put(&data->refcount, data_release);
goto out;
}
diff --git a/Documentation/x86/boot.txt b/Documentation/x86/boot.txt
index 8da3a795083..30b43e1b269 100644
--- a/Documentation/x86/boot.txt
+++ b/Documentation/x86/boot.txt
@@ -599,6 +599,7 @@ Protocol: 2.07+
0x00000000 The default x86/PC environment
0x00000001 lguest
0x00000002 Xen
+ 0x00000003 Moorestown MID
Field name: hardware_subarch_data
Type: write (subarch-dependent)