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-rw-r--r--Documentation/ABI/testing/sysfs-firmware-acpi127
-rw-r--r--Documentation/filesystems/configfs/configfs.txt10
-rw-r--r--Documentation/filesystems/configfs/configfs_example.c14
-rw-r--r--Documentation/filesystems/ubifs.txt164
-rw-r--r--Documentation/i2c/chips/max68752
-rw-r--r--Documentation/i2c/chips/pca953910
-rw-r--r--Documentation/i2c/chips/pcf857412
-rw-r--r--Documentation/i2c/chips/pcf85759
-rw-r--r--Documentation/ioctl/hdio.txt7
-rw-r--r--Documentation/kernel-parameters.txt14
-rw-r--r--Documentation/laptops/acer-wmi.txt2
11 files changed, 299 insertions, 72 deletions
diff --git a/Documentation/ABI/testing/sysfs-firmware-acpi b/Documentation/ABI/testing/sysfs-firmware-acpi
index 9470ed9afcc..f27be7d1a49 100644
--- a/Documentation/ABI/testing/sysfs-firmware-acpi
+++ b/Documentation/ABI/testing/sysfs-firmware-acpi
@@ -29,46 +29,46 @@ Description:
$ cd /sys/firmware/acpi/interrupts
$ grep . *
- error:0
- ff_gbl_lock:0
- ff_pmtimer:0
- ff_pwr_btn:0
- ff_rt_clk:0
- ff_slp_btn:0
- gpe00:0
- gpe01:0
- gpe02:0
- gpe03:0
- gpe04:0
- gpe05:0
- gpe06:0
- gpe07:0
- gpe08:0
- gpe09:174
- gpe0A:0
- gpe0B:0
- gpe0C:0
- gpe0D:0
- gpe0E:0
- gpe0F:0
- gpe10:0
- gpe11:60
- gpe12:0
- gpe13:0
- gpe14:0
- gpe15:0
- gpe16:0
- gpe17:0
- gpe18:0
- gpe19:7
- gpe1A:0
- gpe1B:0
- gpe1C:0
- gpe1D:0
- gpe1E:0
- gpe1F:0
- gpe_all:241
- sci:241
+ error: 0
+ ff_gbl_lock: 0 enable
+ ff_pmtimer: 0 invalid
+ ff_pwr_btn: 0 enable
+ ff_rt_clk: 2 disable
+ ff_slp_btn: 0 invalid
+ gpe00: 0 invalid
+ gpe01: 0 enable
+ gpe02: 108 enable
+ gpe03: 0 invalid
+ gpe04: 0 invalid
+ gpe05: 0 invalid
+ gpe06: 0 enable
+ gpe07: 0 enable
+ gpe08: 0 invalid
+ gpe09: 0 invalid
+ gpe0A: 0 invalid
+ gpe0B: 0 invalid
+ gpe0C: 0 invalid
+ gpe0D: 0 invalid
+ gpe0E: 0 invalid
+ gpe0F: 0 invalid
+ gpe10: 0 invalid
+ gpe11: 0 invalid
+ gpe12: 0 invalid
+ gpe13: 0 invalid
+ gpe14: 0 invalid
+ gpe15: 0 invalid
+ gpe16: 0 invalid
+ gpe17: 1084 enable
+ gpe18: 0 enable
+ gpe19: 0 invalid
+ gpe1A: 0 invalid
+ gpe1B: 0 invalid
+ gpe1C: 0 invalid
+ gpe1D: 0 invalid
+ gpe1E: 0 invalid
+ gpe1F: 0 invalid
+ gpe_all: 1192
+ sci: 1194
sci - The total number of times the ACPI SCI
has claimed an interrupt.
@@ -89,6 +89,13 @@ Description:
error - an interrupt that can't be accounted for above.
+ invalid: it's either a wakeup GPE or a GPE/Fixed Event that
+ doesn't have an event handler.
+
+ disable: the GPE/Fixed Event is valid but disabled.
+
+ enable: the GPE/Fixed Event is valid and enabled.
+
Root has permission to clear any of these counters. Eg.
# echo 0 > gpe11
@@ -97,3 +104,43 @@ Description:
None of these counters has an effect on the function
of the system, they are simply statistics.
+
+ Besides this, user can also write specific strings to these files
+ to enable/disable/clear ACPI interrupts in user space, which can be
+ used to debug some ACPI interrupt storm issues.
+
+ Note that only writting to VALID GPE/Fixed Event is allowed,
+ i.e. user can only change the status of runtime GPE and
+ Fixed Event with event handler installed.
+
+ Let's take power button fixed event for example, please kill acpid
+ and other user space applications so that the machine won't shutdown
+ when pressing the power button.
+ # cat ff_pwr_btn
+ 0
+ # press the power button for 3 times;
+ # cat ff_pwr_btn
+ 3
+ # echo disable > ff_pwr_btn
+ # cat ff_pwr_btn
+ disable
+ # press the power button for 3 times;
+ # cat ff_pwr_btn
+ disable
+ # echo enable > ff_pwr_btn
+ # cat ff_pwr_btn
+ 4
+ /*
+ * this is because the status bit is set even if the enable bit is cleared,
+ * and it triggers an ACPI fixed event when the enable bit is set again
+ */
+ # press the power button for 3 times;
+ # cat ff_pwr_btn
+ 7
+ # echo disable > ff_pwr_btn
+ # press the power button for 3 times;
+ # echo clear > ff_pwr_btn /* clear the status bit */
+ # echo disable > ff_pwr_btn
+ # cat ff_pwr_btn
+ 7
+
diff --git a/Documentation/filesystems/configfs/configfs.txt b/Documentation/filesystems/configfs/configfs.txt
index 44c97e6accb..15838d706ea 100644
--- a/Documentation/filesystems/configfs/configfs.txt
+++ b/Documentation/filesystems/configfs/configfs.txt
@@ -233,10 +233,12 @@ accomplished via the group operations specified on the group's
config_item_type.
struct configfs_group_operations {
- struct config_item *(*make_item)(struct config_group *group,
- const char *name);
- struct config_group *(*make_group)(struct config_group *group,
- const char *name);
+ int (*make_item)(struct config_group *group,
+ const char *name,
+ struct config_item **new_item);
+ int (*make_group)(struct config_group *group,
+ const char *name,
+ struct config_group **new_group);
int (*commit_item)(struct config_item *item);
void (*disconnect_notify)(struct config_group *group,
struct config_item *item);
diff --git a/Documentation/filesystems/configfs/configfs_example.c b/Documentation/filesystems/configfs/configfs_example.c
index 25151fd5c2c..0b422acd470 100644
--- a/Documentation/filesystems/configfs/configfs_example.c
+++ b/Documentation/filesystems/configfs/configfs_example.c
@@ -273,13 +273,13 @@ static inline struct simple_children *to_simple_children(struct config_item *ite
return item ? container_of(to_config_group(item), struct simple_children, group) : NULL;
}
-static struct config_item *simple_children_make_item(struct config_group *group, const char *name)
+static int simple_children_make_item(struct config_group *group, const char *name, struct config_item **new_item)
{
struct simple_child *simple_child;
simple_child = kzalloc(sizeof(struct simple_child), GFP_KERNEL);
if (!simple_child)
- return NULL;
+ return -ENOMEM;
config_item_init_type_name(&simple_child->item, name,
@@ -287,7 +287,8 @@ static struct config_item *simple_children_make_item(struct config_group *group,
simple_child->storeme = 0;
- return &simple_child->item;
+ *new_item = &simple_child->item;
+ return 0;
}
static struct configfs_attribute simple_children_attr_description = {
@@ -359,20 +360,21 @@ static struct configfs_subsystem simple_children_subsys = {
* children of its own.
*/
-static struct config_group *group_children_make_group(struct config_group *group, const char *name)
+static int group_children_make_group(struct config_group *group, const char *name, struct config_group **new_group)
{
struct simple_children *simple_children;
simple_children = kzalloc(sizeof(struct simple_children),
GFP_KERNEL);
if (!simple_children)
- return NULL;
+ return -ENOMEM;
config_group_init_type_name(&simple_children->group, name,
&simple_children_type);
- return &simple_children->group;
+ *new_group = &simple_children->group;
+ return 0;
}
static struct configfs_attribute group_children_attr_description = {
diff --git a/Documentation/filesystems/ubifs.txt b/Documentation/filesystems/ubifs.txt
new file mode 100644
index 00000000000..540e9e7f59c
--- /dev/null
+++ b/Documentation/filesystems/ubifs.txt
@@ -0,0 +1,164 @@
+Introduction
+=============
+
+UBIFS file-system stands for UBI File System. UBI stands for "Unsorted
+Block Images". UBIFS is a flash file system, which means it is designed
+to work with flash devices. It is important to understand, that UBIFS
+is completely different to any traditional file-system in Linux, like
+Ext2, XFS, JFS, etc. UBIFS represents a separate class of file-systems
+which work with MTD devices, not block devices. The other Linux
+file-system of this class is JFFS2.
+
+To make it more clear, here is a small comparison of MTD devices and
+block devices.
+
+1 MTD devices represent flash devices and they consist of eraseblocks of
+ rather large size, typically about 128KiB. Block devices consist of
+ small blocks, typically 512 bytes.
+2 MTD devices support 3 main operations - read from some offset within an
+ eraseblock, write to some offset within an eraseblock, and erase a whole
+ eraseblock. Block devices support 2 main operations - read a whole
+ block and write a whole block.
+3 The whole eraseblock has to be erased before it becomes possible to
+ re-write its contents. Blocks may be just re-written.
+4 Eraseblocks become worn out after some number of erase cycles -
+ typically 100K-1G for SLC NAND and NOR flashes, and 1K-10K for MLC
+ NAND flashes. Blocks do not have the wear-out property.
+5 Eraseblocks may become bad (only on NAND flashes) and software should
+ deal with this. Blocks on hard drives typically do not become bad,
+ because hardware has mechanisms to substitute bad blocks, at least in
+ modern LBA disks.
+
+It should be quite obvious why UBIFS is very different to traditional
+file-systems.
+
+UBIFS works on top of UBI. UBI is a separate software layer which may be
+found in drivers/mtd/ubi. UBI is basically a volume management and
+wear-leveling layer. It provides so called UBI volumes which is a higher
+level abstraction than a MTD device. The programming model of UBI devices
+is very similar to MTD devices - they still consist of large eraseblocks,
+they have read/write/erase operations, but UBI devices are devoid of
+limitations like wear and bad blocks (items 4 and 5 in the above list).
+
+In a sense, UBIFS is a next generation of JFFS2 file-system, but it is
+very different and incompatible to JFFS2. The following are the main
+differences.
+
+* JFFS2 works on top of MTD devices, UBIFS depends on UBI and works on
+ top of UBI volumes.
+* JFFS2 does not have on-media index and has to build it while mounting,
+ which requires full media scan. UBIFS maintains the FS indexing
+ information on the flash media and does not require full media scan,
+ so it mounts many times faster than JFFS2.
+* JFFS2 is a write-through file-system, while UBIFS supports write-back,
+ which makes UBIFS much faster on writes.
+
+Similarly to JFFS2, UBIFS supports on-the-flight compression which makes
+it possible to fit quite a lot of data to the flash.
+
+Similarly to JFFS2, UBIFS is tolerant of unclean reboots and power-cuts.
+It does not need stuff like ckfs.ext2. UBIFS automatically replays its
+journal and recovers from crashes, ensuring that the on-flash data
+structures are consistent.
+
+UBIFS scales logarithmically (most of the data structures it uses are
+trees), so the mount time and memory consumption do not linearly depend
+on the flash size, like in case of JFFS2. This is because UBIFS
+maintains the FS index on the flash media. However, UBIFS depends on
+UBI, which scales linearly. So overall UBI/UBIFS stack scales linearly.
+Nevertheless, UBI/UBIFS scales considerably better than JFFS2.
+
+The authors of UBIFS believe, that it is possible to develop UBI2 which
+would scale logarithmically as well. UBI2 would support the same API as UBI,
+but it would be binary incompatible to UBI. So UBIFS would not need to be
+changed to use UBI2
+
+
+Mount options
+=============
+
+(*) == default.
+
+norm_unmount (*) commit on unmount; the journal is committed
+ when the file-system is unmounted so that the
+ next mount does not have to replay the journal
+ and it becomes very fast;
+fast_unmount do not commit on unmount; this option makes
+ unmount faster, but the next mount slower
+ because of the need to replay the journal.
+
+
+Quick usage instructions
+========================
+
+The UBI volume to mount is specified using "ubiX_Y" or "ubiX:NAME" syntax,
+where "X" is UBI device number, "Y" is UBI volume number, and "NAME" is
+UBI volume name.
+
+Mount volume 0 on UBI device 0 to /mnt/ubifs:
+$ mount -t ubifs ubi0_0 /mnt/ubifs
+
+Mount "rootfs" volume of UBI device 0 to /mnt/ubifs ("rootfs" is volume
+name):
+$ mount -t ubifs ubi0:rootfs /mnt/ubifs
+
+The following is an example of the kernel boot arguments to attach mtd0
+to UBI and mount volume "rootfs":
+ubi.mtd=0 root=ubi0:rootfs rootfstype=ubifs
+
+
+Module Parameters for Debugging
+===============================
+
+When UBIFS has been compiled with debugging enabled, there are 3 module
+parameters that are available to control aspects of testing and debugging.
+The parameters are unsigned integers where each bit controls an option.
+The parameters are:
+
+debug_msgs Selects which debug messages to display, as follows:
+
+ Message Type Flag value
+
+ General messages 1
+ Journal messages 2
+ Mount messages 4
+ Commit messages 8
+ LEB search messages 16
+ Budgeting messages 32
+ Garbage collection messages 64
+ Tree Node Cache (TNC) messages 128
+ LEB properties (lprops) messages 256
+ Input/output messages 512
+ Log messages 1024
+ Scan messages 2048
+ Recovery messages 4096
+
+debug_chks Selects extra checks that UBIFS can do while running:
+
+ Check Flag value
+
+ General checks 1
+ Check Tree Node Cache (TNC) 2
+ Check indexing tree size 4
+ Check orphan area 8
+ Check old indexing tree 16
+ Check LEB properties (lprops) 32
+ Check leaf nodes and inodes 64
+
+debug_tsts Selects a mode of testing, as follows:
+
+ Test mode Flag value
+
+ Force in-the-gaps method 2
+ Failure mode for recovery testing 4
+
+For example, set debug_msgs to 5 to display General messages and Mount
+messages.
+
+
+References
+==========
+
+UBIFS documentation and FAQ/HOWTO at the MTD web site:
+http://www.linux-mtd.infradead.org/doc/ubifs.html
+http://www.linux-mtd.infradead.org/faq/ubifs.html
diff --git a/Documentation/i2c/chips/max6875 b/Documentation/i2c/chips/max6875
index a0cd8af2f40..10ca43cd1a7 100644
--- a/Documentation/i2c/chips/max6875
+++ b/Documentation/i2c/chips/max6875
@@ -49,7 +49,7 @@ $ modprobe max6875 force=0,0x50
The MAX6874/MAX6875 ignores address bit 0, so this driver attaches to multiple
addresses. For example, for address 0x50, it also reserves 0x51.
-The even-address instance is called 'max6875', the odd one is 'max6875 subclient'.
+The even-address instance is called 'max6875', the odd one is 'dummy'.
Programming the chip using i2c-dev
diff --git a/Documentation/i2c/chips/pca9539 b/Documentation/i2c/chips/pca9539
index 1d81c530c4a..6aff890088b 100644
--- a/Documentation/i2c/chips/pca9539
+++ b/Documentation/i2c/chips/pca9539
@@ -7,7 +7,7 @@ drivers/gpio/pca9539.c instead.
Supported chips:
* Philips PCA9539
Prefix: 'pca9539'
- Addresses scanned: 0x74 - 0x77
+ Addresses scanned: none
Datasheet:
http://www.semiconductors.philips.com/acrobat/datasheets/PCA9539_2.pdf
@@ -23,6 +23,14 @@ The input sense can also be inverted.
The 16 lines are split between two bytes.
+Detection
+---------
+
+The PCA9539 is difficult to detect and not commonly found in PC machines,
+so you have to pass the I2C bus and address of the installed PCA9539
+devices explicitly to the driver at load time via the force=... parameter.
+
+
Sysfs entries
-------------
diff --git a/Documentation/i2c/chips/pcf8574 b/Documentation/i2c/chips/pcf8574
index 5c1ad1376b6..235815c075f 100644
--- a/Documentation/i2c/chips/pcf8574
+++ b/Documentation/i2c/chips/pcf8574
@@ -4,13 +4,13 @@ Kernel driver pcf8574
Supported chips:
* Philips PCF8574
Prefix: 'pcf8574'
- Addresses scanned: I2C 0x20 - 0x27
+ Addresses scanned: none
Datasheet: Publicly available at the Philips Semiconductors website
http://www.semiconductors.philips.com/pip/PCF8574P.html
* Philips PCF8574A
Prefix: 'pcf8574a'
- Addresses scanned: I2C 0x38 - 0x3f
+ Addresses scanned: none
Datasheet: Publicly available at the Philips Semiconductors website
http://www.semiconductors.philips.com/pip/PCF8574P.html
@@ -38,12 +38,10 @@ For more informations see the datasheet.
Accessing PCF8574(A) via /sys interface
-------------------------------------
-! Be careful !
The PCF8574(A) is plainly impossible to detect ! Stupid chip.
-So every chip with address in the interval [20..27] and [38..3f] are
-detected as PCF8574(A). If you have other chips in this address
-range, the workaround is to load this module after the one
-for your others chips.
+So, you have to pass the I2C bus and address of the installed PCF857A
+and PCF8574A devices explicitly to the driver at load time via the
+force=... parameter.
On detection (i.e. insmod, modprobe et al.), directories are being
created for each detected PCF8574(A):
diff --git a/Documentation/i2c/chips/pcf8575 b/Documentation/i2c/chips/pcf8575
index 25f5698a61c..40b268eb276 100644
--- a/Documentation/i2c/chips/pcf8575
+++ b/Documentation/i2c/chips/pcf8575
@@ -40,12 +40,9 @@ Detection
---------
There is no method known to detect whether a chip on a given I2C address is
-a PCF8575 or whether it is any other I2C device. So there are two alternatives
-to let the driver find the installed PCF8575 devices:
-- Load this driver after any other I2C driver for I2C devices with addresses
- in the range 0x20 .. 0x27.
-- Pass the I2C bus and address of the installed PCF8575 devices explicitly to
- the driver at load time via the probe=... or force=... parameters.
+a PCF8575 or whether it is any other I2C device, so you have to pass the I2C
+bus and address of the installed PCF8575 devices explicitly to the driver at
+load time via the force=... parameter.
/sys interface
--------------
diff --git a/Documentation/ioctl/hdio.txt b/Documentation/ioctl/hdio.txt
index c19efdeace2..91a6ecbae0b 100644
--- a/Documentation/ioctl/hdio.txt
+++ b/Documentation/ioctl/hdio.txt
@@ -508,12 +508,13 @@ HDIO_DRIVE_RESET execute a device reset
error returns:
EACCES Access denied: requires CAP_SYS_ADMIN
+ ENXIO No such device: phy dead or ctl_addr == 0
+ EIO I/O error: reset timed out or hardware error
notes:
- Abort any current command, prevent anything else from being
- queued, execute a reset on the device, and issue BLKRRPART
- ioctl on the block device.
+ Execute a reset on the device as soon as the current IO
+ operation has completed.
Executes an ATAPI soft reset if applicable, otherwise
executes an ATA soft reset on the controller.
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 312fe77764a..09ad7450647 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -147,10 +147,14 @@ and is between 256 and 4096 characters. It is defined in the file
default: 0
acpi_sleep= [HW,ACPI] Sleep options
- Format: { s3_bios, s3_mode, s3_beep }
+ Format: { s3_bios, s3_mode, s3_beep, old_ordering }
See Documentation/power/video.txt for s3_bios and s3_mode.
s3_beep is for debugging; it makes the PC's speaker beep
as soon as the kernel's real-mode entry point is called.
+ old_ordering causes the ACPI 1.0 ordering of the _PTS
+ control method, wrt putting devices into low power
+ states, to be enforced (the ACPI 2.0 ordering of _PTS is
+ used by default).
acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
Format: { level | edge | high | low }
@@ -818,7 +822,7 @@ and is between 256 and 4096 characters. It is defined in the file
See Documentation/ide/ide.txt.
idle= [X86]
- Format: idle=poll or idle=mwait
+ Format: idle=poll or idle=mwait, idle=halt, idle=nomwait
Poll forces a polling idle loop that can slightly improves the performance
of waking up a idle CPU, but will use a lot of power and make the system
run hot. Not recommended.
@@ -826,6 +830,9 @@ and is between 256 and 4096 characters. It is defined in the file
to not use it because it doesn't save as much power as a normal idle
loop use the MONITOR/MWAIT idle loop anyways. Performance should be the same
as idle=poll.
+ idle=halt. Halt is forced to be used for CPU idle.
+ In such case C2/C3 won't be used again.
+ idle=nomwait. Disable mwait for CPU C-states
ide-pci-generic.all-generic-ide [HW] (E)IDE subsystem
Claim all unknown PCI IDE storage controllers.
@@ -1534,6 +1541,9 @@ and is between 256 and 4096 characters. It is defined in the file
Use with caution as certain devices share
address decoders between ROMs and other
resources.
+ norom [X86-32,X86_64] Do not assign address space to
+ expansion ROMs that do not already have
+ BIOS assigned address ranges.
irqmask=0xMMMM [X86-32] Set a bit mask of IRQs allowed to be
assigned automatically to PCI devices. You can
make the kernel exclude IRQs of your ISA cards
diff --git a/Documentation/laptops/acer-wmi.txt b/Documentation/laptops/acer-wmi.txt
index 79b7dbd2214..69b5dd4e5a5 100644
--- a/Documentation/laptops/acer-wmi.txt
+++ b/Documentation/laptops/acer-wmi.txt
@@ -174,8 +174,6 @@ The LED is exposed through the LED subsystem, and can be found in:
The mail LED is autodetected, so if you don't have one, the LED device won't
be registered.
-If you have a mail LED that is not green, please report this to me.
-
Backlight
*********