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-rw-r--r--Documentation/IPMI.txt13
-rw-r--r--Documentation/RCU/NMI-RCU.txt112
-rw-r--r--Documentation/cdrom/sonycd5353
-rw-r--r--Documentation/cpusets.txt12
-rw-r--r--Documentation/dcdbas.txt91
-rw-r--r--Documentation/dell_rbu.txt74
-rw-r--r--Documentation/dvb/bt8xx.txt2
-rw-r--r--Documentation/exception.txt2
-rw-r--r--Documentation/feature-removal-schedule.txt16
-rw-r--r--Documentation/filesystems/relayfs.txt362
-rw-r--r--Documentation/i386/boot.txt35
-rw-r--r--Documentation/kernel-parameters.txt5
-rw-r--r--Documentation/power/swsusp.txt101
-rw-r--r--Documentation/power/video.txt1
-rw-r--r--Documentation/sonypi.txt10
15 files changed, 756 insertions, 83 deletions
diff --git a/Documentation/IPMI.txt b/Documentation/IPMI.txt
index 84d3d4d10c17..bf1cf98d2a27 100644
--- a/Documentation/IPMI.txt
+++ b/Documentation/IPMI.txt
@@ -605,12 +605,13 @@ is in the ipmi_poweroff module. When the system requests a powerdown,
605it will send the proper IPMI commands to do this. This is supported on 605it will send the proper IPMI commands to do this. This is supported on
606several platforms. 606several platforms.
607 607
608There is a module parameter named "poweroff_control" that may either be zero 608There is a module parameter named "poweroff_powercycle" that may
609(do a power down) or 2 (do a power cycle, power the system off, then power 609either be zero (do a power down) or non-zero (do a power cycle, power
610it on in a few seconds). Setting ipmi_poweroff.poweroff_control=x will do 610the system off, then power it on in a few seconds). Setting
611the same thing on the kernel command line. The parameter is also available 611ipmi_poweroff.poweroff_control=x will do the same thing on the kernel
612via the proc filesystem in /proc/ipmi/poweroff_control. Note that if the 612command line. The parameter is also available via the proc filesystem
613system does not support power cycling, it will always to the power off. 613in /proc/sys/dev/ipmi/poweroff_powercycle. Note that if the system
614does not support power cycling, it will always do the power off.
614 615
615Note that if you have ACPI enabled, the system will prefer using ACPI to 616Note that if you have ACPI enabled, the system will prefer using ACPI to
616power off. 617power off.
diff --git a/Documentation/RCU/NMI-RCU.txt b/Documentation/RCU/NMI-RCU.txt
new file mode 100644
index 000000000000..d0634a5c3445
--- /dev/null
+++ b/Documentation/RCU/NMI-RCU.txt
@@ -0,0 +1,112 @@
1Using RCU to Protect Dynamic NMI Handlers
2
3
4Although RCU is usually used to protect read-mostly data structures,
5it is possible to use RCU to provide dynamic non-maskable interrupt
6handlers, as well as dynamic irq handlers. This document describes
7how to do this, drawing loosely from Zwane Mwaikambo's NMI-timer
8work in "arch/i386/oprofile/nmi_timer_int.c" and in
9"arch/i386/kernel/traps.c".
10
11The relevant pieces of code are listed below, each followed by a
12brief explanation.
13
14 static int dummy_nmi_callback(struct pt_regs *regs, int cpu)
15 {
16 return 0;
17 }
18
19The dummy_nmi_callback() function is a "dummy" NMI handler that does
20nothing, but returns zero, thus saying that it did nothing, allowing
21the NMI handler to take the default machine-specific action.
22
23 static nmi_callback_t nmi_callback = dummy_nmi_callback;
24
25This nmi_callback variable is a global function pointer to the current
26NMI handler.
27
28 fastcall void do_nmi(struct pt_regs * regs, long error_code)
29 {
30 int cpu;
31
32 nmi_enter();
33
34 cpu = smp_processor_id();
35 ++nmi_count(cpu);
36
37 if (!rcu_dereference(nmi_callback)(regs, cpu))
38 default_do_nmi(regs);
39
40 nmi_exit();
41 }
42
43The do_nmi() function processes each NMI. It first disables preemption
44in the same way that a hardware irq would, then increments the per-CPU
45count of NMIs. It then invokes the NMI handler stored in the nmi_callback
46function pointer. If this handler returns zero, do_nmi() invokes the
47default_do_nmi() function to handle a machine-specific NMI. Finally,
48preemption is restored.
49
50Strictly speaking, rcu_dereference() is not needed, since this code runs
51only on i386, which does not need rcu_dereference() anyway. However,
52it is a good documentation aid, particularly for anyone attempting to
53do something similar on Alpha.
54
55Quick Quiz: Why might the rcu_dereference() be necessary on Alpha,
56 given that the code referenced by the pointer is read-only?
57
58
59Back to the discussion of NMI and RCU...
60
61 void set_nmi_callback(nmi_callback_t callback)
62 {
63 rcu_assign_pointer(nmi_callback, callback);
64 }
65
66The set_nmi_callback() function registers an NMI handler. Note that any
67data that is to be used by the callback must be initialized up -before-
68the call to set_nmi_callback(). On architectures that do not order
69writes, the rcu_assign_pointer() ensures that the NMI handler sees the
70initialized values.
71
72 void unset_nmi_callback(void)
73 {
74 rcu_assign_pointer(nmi_callback, dummy_nmi_callback);
75 }
76
77This function unregisters an NMI handler, restoring the original
78dummy_nmi_handler(). However, there may well be an NMI handler
79currently executing on some other CPU. We therefore cannot free
80up any data structures used by the old NMI handler until execution
81of it completes on all other CPUs.
82
83One way to accomplish this is via synchronize_sched(), perhaps as
84follows:
85
86 unset_nmi_callback();
87 synchronize_sched();
88 kfree(my_nmi_data);
89
90This works because synchronize_sched() blocks until all CPUs complete
91any preemption-disabled segments of code that they were executing.
92Since NMI handlers disable preemption, synchronize_sched() is guaranteed
93not to return until all ongoing NMI handlers exit. It is therefore safe
94to free up the handler's data as soon as synchronize_sched() returns.
95
96
97Answer to Quick Quiz
98
99 Why might the rcu_dereference() be necessary on Alpha, given
100 that the code referenced by the pointer is read-only?
101
102 Answer: The caller to set_nmi_callback() might well have
103 initialized some data that is to be used by the
104 new NMI handler. In this case, the rcu_dereference()
105 would be needed, because otherwise a CPU that received
106 an NMI just after the new handler was set might see
107 the pointer to the new NMI handler, but the old
108 pre-initialized version of the handler's data.
109
110 More important, the rcu_dereference() makes it clear
111 to someone reading the code that the pointer is being
112 protected by RCU.
diff --git a/Documentation/cdrom/sonycd535 b/Documentation/cdrom/sonycd535
index 59581a4b302a..b81e109970aa 100644
--- a/Documentation/cdrom/sonycd535
+++ b/Documentation/cdrom/sonycd535
@@ -68,7 +68,8 @@ it a better device citizen. Further thanks to Joel Katz
68Porfiri Claudio <C.Porfiri@nisms.tei.ericsson.se> for patches 68Porfiri Claudio <C.Porfiri@nisms.tei.ericsson.se> for patches
69to make the driver work with the older CDU-510/515 series, and 69to make the driver work with the older CDU-510/515 series, and
70Heiko Eissfeldt <heiko@colossus.escape.de> for pointing out that 70Heiko Eissfeldt <heiko@colossus.escape.de> for pointing out that
71the verify_area() checks were ignoring the results of said checks. 71the verify_area() checks were ignoring the results of said checks
72(note: verify_area() has since been replaced by access_ok()).
72 73
73(Acknowledgments from Ron Jeppesen in the 0.3 release:) 74(Acknowledgments from Ron Jeppesen in the 0.3 release:)
74Thanks to Corey Minyard who wrote the original CDU-31A driver on which 75Thanks to Corey Minyard who wrote the original CDU-31A driver on which
diff --git a/Documentation/cpusets.txt b/Documentation/cpusets.txt
index ad944c060312..47f4114fbf54 100644
--- a/Documentation/cpusets.txt
+++ b/Documentation/cpusets.txt
@@ -60,6 +60,18 @@ all of the cpus in the system. This removes any overhead due to
60load balancing code trying to pull tasks outside of the cpu exclusive 60load balancing code trying to pull tasks outside of the cpu exclusive
61cpuset only to be prevented by the tasks' cpus_allowed mask. 61cpuset only to be prevented by the tasks' cpus_allowed mask.
62 62
63A cpuset that is mem_exclusive restricts kernel allocations for
64page, buffer and other data commonly shared by the kernel across
65multiple users. All cpusets, whether mem_exclusive or not, restrict
66allocations of memory for user space. This enables configuring a
67system so that several independent jobs can share common kernel
68data, such as file system pages, while isolating each jobs user
69allocation in its own cpuset. To do this, construct a large
70mem_exclusive cpuset to hold all the jobs, and construct child,
71non-mem_exclusive cpusets for each individual job. Only a small
72amount of typical kernel memory, such as requests from interrupt
73handlers, is allowed to be taken outside even a mem_exclusive cpuset.
74
63User level code may create and destroy cpusets by name in the cpuset 75User level code may create and destroy cpusets by name in the cpuset
64virtual file system, manage the attributes and permissions of these 76virtual file system, manage the attributes and permissions of these
65cpusets and which CPUs and Memory Nodes are assigned to each cpuset, 77cpusets and which CPUs and Memory Nodes are assigned to each cpuset,
diff --git a/Documentation/dcdbas.txt b/Documentation/dcdbas.txt
new file mode 100644
index 000000000000..e1c52e2dc361
--- /dev/null
+++ b/Documentation/dcdbas.txt
@@ -0,0 +1,91 @@
1Overview
2
3The Dell Systems Management Base Driver provides a sysfs interface for
4systems management software such as Dell OpenManage to perform system
5management interrupts and host control actions (system power cycle or
6power off after OS shutdown) on certain Dell systems.
7
8Dell OpenManage requires this driver on the following Dell PowerEdge systems:
9300, 1300, 1400, 400SC, 500SC, 1500SC, 1550, 600SC, 1600SC, 650, 1655MC,
10700, and 750. Other Dell software such as the open source libsmbios project
11is expected to make use of this driver, and it may include the use of this
12driver on other Dell systems.
13
14The Dell libsmbios project aims towards providing access to as much BIOS
15information as possible. See http://linux.dell.com/libsmbios/main/ for
16more information about the libsmbios project.
17
18
19System Management Interrupt
20
21On some Dell systems, systems management software must access certain
22management information via a system management interrupt (SMI). The SMI data
23buffer must reside in 32-bit address space, and the physical address of the
24buffer is required for the SMI. The driver maintains the memory required for
25the SMI and provides a way for the application to generate the SMI.
26The driver creates the following sysfs entries for systems management
27software to perform these system management interrupts:
28
29/sys/devices/platform/dcdbas/smi_data
30/sys/devices/platform/dcdbas/smi_data_buf_phys_addr
31/sys/devices/platform/dcdbas/smi_data_buf_size
32/sys/devices/platform/dcdbas/smi_request
33
34Systems management software must perform the following steps to execute
35a SMI using this driver:
36
371) Lock smi_data.
382) Write system management command to smi_data.
393) Write "1" to smi_request to generate a calling interface SMI or
40 "2" to generate a raw SMI.
414) Read system management command response from smi_data.
425) Unlock smi_data.
43
44
45Host Control Action
46
47Dell OpenManage supports a host control feature that allows the administrator
48to perform a power cycle or power off of the system after the OS has finished
49shutting down. On some Dell systems, this host control feature requires that
50a driver perform a SMI after the OS has finished shutting down.
51
52The driver creates the following sysfs entries for systems management software
53to schedule the driver to perform a power cycle or power off host control
54action after the system has finished shutting down:
55
56/sys/devices/platform/dcdbas/host_control_action
57/sys/devices/platform/dcdbas/host_control_smi_type
58/sys/devices/platform/dcdbas/host_control_on_shutdown
59
60Dell OpenManage performs the following steps to execute a power cycle or
61power off host control action using this driver:
62
631) Write host control action to be performed to host_control_action.
642) Write type of SMI that driver needs to perform to host_control_smi_type.
653) Write "1" to host_control_on_shutdown to enable host control action.
664) Initiate OS shutdown.
67 (Driver will perform host control SMI when it is notified that the OS
68 has finished shutting down.)
69
70
71Host Control SMI Type
72
73The following table shows the value to write to host_control_smi_type to
74perform a power cycle or power off host control action:
75
76PowerEdge System Host Control SMI Type
77---------------- ---------------------
78 300 HC_SMITYPE_TYPE1
79 1300 HC_SMITYPE_TYPE1
80 1400 HC_SMITYPE_TYPE2
81 500SC HC_SMITYPE_TYPE2
82 1500SC HC_SMITYPE_TYPE2
83 1550 HC_SMITYPE_TYPE2
84 600SC HC_SMITYPE_TYPE2
85 1600SC HC_SMITYPE_TYPE2
86 650 HC_SMITYPE_TYPE2
87 1655MC HC_SMITYPE_TYPE2
88 700 HC_SMITYPE_TYPE3
89 750 HC_SMITYPE_TYPE3
90
91
diff --git a/Documentation/dell_rbu.txt b/Documentation/dell_rbu.txt
new file mode 100644
index 000000000000..bcfa5c35036b
--- /dev/null
+++ b/Documentation/dell_rbu.txt
@@ -0,0 +1,74 @@
1Purpose:
2Demonstrate the usage of the new open sourced rbu (Remote BIOS Update) driver
3for updating BIOS images on Dell servers and desktops.
4
5Scope:
6This document discusses the functionality of the rbu driver only.
7It does not cover the support needed from aplications to enable the BIOS to
8update itself with the image downloaded in to the memory.
9
10Overview:
11This driver works with Dell OpenManage or Dell Update Packages for updating
12the BIOS on Dell servers (starting from servers sold since 1999), desktops
13and notebooks (starting from those sold in 2005).
14Please go to http://support.dell.com register and you can find info on
15OpenManage and Dell Update packages (DUP).
16
17Dell_RBU driver supports BIOS update using the monilothic image and packetized
18image methods. In case of moniolithic the driver allocates a contiguous chunk
19of physical pages having the BIOS image. In case of packetized the app
20using the driver breaks the image in to packets of fixed sizes and the driver
21would place each packet in contiguous physical memory. The driver also
22maintains a link list of packets for reading them back.
23If the dell_rbu driver is unloaded all the allocated memory is freed.
24
25The rbu driver needs to have an application which will inform the BIOS to
26enable the update in the next system reboot.
27
28The user should not unload the rbu driver after downloading the BIOS image
29or updating.
30
31The driver load creates the following directories under the /sys file system.
32/sys/class/firmware/dell_rbu/loading
33/sys/class/firmware/dell_rbu/data
34/sys/devices/platform/dell_rbu/image_type
35/sys/devices/platform/dell_rbu/data
36
37The driver supports two types of update mechanism; monolithic and packetized.
38These update mechanism depends upon the BIOS currently running on the system.
39Most of the Dell systems support a monolithic update where the BIOS image is
40copied to a single contiguous block of physical memory.
41In case of packet mechanism the single memory can be broken in smaller chuks
42of contiguous memory and the BIOS image is scattered in these packets.
43
44By default the driver uses monolithic memory for the update type. This can be
45changed to contiguous during the driver load time by specifying the load
46parameter image_type=packet. This can also be changed later as below
47echo packet > /sys/devices/platform/dell_rbu/image_type
48
49Do the steps below to download the BIOS image.
501) echo 1 > /sys/class/firmware/dell_rbu/loading
512) cp bios_image.hdr /sys/class/firmware/dell_rbu/data
523) echo 0 > /sys/class/firmware/dell_rbu/loading
53
54The /sys/class/firmware/dell_rbu/ entries will remain till the following is
55done.
56echo -1 > /sys/class/firmware/dell_rbu/loading
57
58Until this step is completed the drivr cannot be unloaded.
59
60Also the driver provides /sys/devices/platform/dell_rbu/data readonly file to
61read back the image downloaded. This is useful in case of packet update
62mechanism where the above steps 1,2,3 will repeated for every packet.
63By reading the /sys/devices/platform/dell_rbu/data file all packet data
64downloaded can be verified in a single file.
65The packets are arranged in this file one after the other in a FIFO order.
66
67NOTE:
68This driver requires a patch for firmware_class.c which has the addition
69of request_firmware_nowait_nohotplug function to wortk
70Also after updating the BIOS image an user mdoe application neeeds to execute
71code which message the BIOS update request to the BIOS. So on the next reboot
72the BIOS knows about the new image downloaded and it updates it self.
73Also don't unload the rbu drive if the image has to be updated.
74
diff --git a/Documentation/dvb/bt8xx.txt b/Documentation/dvb/bt8xx.txt
index e6b8d05bc08d..4b8c326c6aac 100644
--- a/Documentation/dvb/bt8xx.txt
+++ b/Documentation/dvb/bt8xx.txt
@@ -16,7 +16,7 @@ Enable the following options:
16"Device drivers" => "Multimedia devices" 16"Device drivers" => "Multimedia devices"
17 => "Video For Linux" => "BT848 Video For Linux" 17 => "Video For Linux" => "BT848 Video For Linux"
18"Device drivers" => "Multimedia devices" => "Digital Video Broadcasting Devices" 18"Device drivers" => "Multimedia devices" => "Digital Video Broadcasting Devices"
19 => "DVB for Linux" "DVB Core Support" "Nebula/Pinnacle PCTV/TwinHan PCI Cards" 19 => "DVB for Linux" "DVB Core Support" "BT8xx based PCI cards"
20 20
213) Loading Modules, described by two approaches 213) Loading Modules, described by two approaches
22=============================================== 22===============================================
diff --git a/Documentation/exception.txt b/Documentation/exception.txt
index f1d436993eb1..3cb39ade290e 100644
--- a/Documentation/exception.txt
+++ b/Documentation/exception.txt
@@ -7,7 +7,7 @@ To protect itself the kernel has to verify this address.
7 7
8In older versions of Linux this was done with the 8In older versions of Linux this was done with the
9int verify_area(int type, const void * addr, unsigned long size) 9int verify_area(int type, const void * addr, unsigned long size)
10function. 10function (which has since been replaced by access_ok()).
11 11
12This function verified that the memory area starting at address 12This function verified that the memory area starting at address
13addr and of size size was accessible for the operation specified 13addr and of size size was accessible for the operation specified
diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
index 363909056e46..2e0a01b21fe0 100644
--- a/Documentation/feature-removal-schedule.txt
+++ b/Documentation/feature-removal-schedule.txt
@@ -51,14 +51,6 @@ Who: Adrian Bunk <bunk@stusta.de>
51 51
52--------------------------- 52---------------------------
53 53
54What: register_ioctl32_conversion() / unregister_ioctl32_conversion()
55When: April 2005
56Why: Replaced by ->compat_ioctl in file_operations and other method
57 vecors.
58Who: Andi Kleen <ak@muc.de>, Christoph Hellwig <hch@lst.de>
59
60---------------------------
61
62What: RCU API moves to EXPORT_SYMBOL_GPL 54What: RCU API moves to EXPORT_SYMBOL_GPL
63When: April 2006 55When: April 2006
64Files: include/linux/rcupdate.h, kernel/rcupdate.c 56Files: include/linux/rcupdate.h, kernel/rcupdate.c
@@ -74,14 +66,6 @@ Who: Paul E. McKenney <paulmck@us.ibm.com>
74 66
75--------------------------- 67---------------------------
76 68
77What: remove verify_area()
78When: July 2006
79Files: Various uaccess.h headers.
80Why: Deprecated and redundant. access_ok() should be used instead.
81Who: Jesper Juhl <juhl-lkml@dif.dk>
82
83---------------------------
84
85What: IEEE1394 Audio and Music Data Transmission Protocol driver, 69What: IEEE1394 Audio and Music Data Transmission Protocol driver,
86 Connection Management Procedures driver 70 Connection Management Procedures driver
87When: November 2005 71When: November 2005
diff --git a/Documentation/filesystems/relayfs.txt b/Documentation/filesystems/relayfs.txt
new file mode 100644
index 000000000000..d24e1b0d4f39
--- /dev/null
+++ b/Documentation/filesystems/relayfs.txt
@@ -0,0 +1,362 @@
1
2relayfs - a high-speed data relay filesystem
3============================================
4
5relayfs is a filesystem designed to provide an efficient mechanism for
6tools and facilities to relay large and potentially sustained streams
7of data from kernel space to user space.
8
9The main abstraction of relayfs is the 'channel'. A channel consists
10of a set of per-cpu kernel buffers each represented by a file in the
11relayfs filesystem. Kernel clients write into a channel using
12efficient write functions which automatically log to the current cpu's
13channel buffer. User space applications mmap() the per-cpu files and
14retrieve the data as it becomes available.
15
16The format of the data logged into the channel buffers is completely
17up to the relayfs client; relayfs does however provide hooks which
18allow clients to impose some stucture on the buffer data. Nor does
19relayfs implement any form of data filtering - this also is left to
20the client. The purpose is to keep relayfs as simple as possible.
21
22This document provides an overview of the relayfs API. The details of
23the function parameters are documented along with the functions in the
24filesystem code - please see that for details.
25
26Semantics
27=========
28
29Each relayfs channel has one buffer per CPU, each buffer has one or
30more sub-buffers. Messages are written to the first sub-buffer until
31it is too full to contain a new message, in which case it it is
32written to the next (if available). Messages are never split across
33sub-buffers. At this point, userspace can be notified so it empties
34the first sub-buffer, while the kernel continues writing to the next.
35
36When notified that a sub-buffer is full, the kernel knows how many
37bytes of it are padding i.e. unused. Userspace can use this knowledge
38to copy only valid data.
39
40After copying it, userspace can notify the kernel that a sub-buffer
41has been consumed.
42
43relayfs can operate in a mode where it will overwrite data not yet
44collected by userspace, and not wait for it to consume it.
45
46relayfs itself does not provide for communication of such data between
47userspace and kernel, allowing the kernel side to remain simple and not
48impose a single interface on userspace. It does provide a separate
49helper though, described below.
50
51klog, relay-app & librelay
52==========================
53
54relayfs itself is ready to use, but to make things easier, two
55additional systems are provided. klog is a simple wrapper to make
56writing formatted text or raw data to a channel simpler, regardless of
57whether a channel to write into exists or not, or whether relayfs is
58compiled into the kernel or is configured as a module. relay-app is
59the kernel counterpart of userspace librelay.c, combined these two
60files provide glue to easily stream data to disk, without having to
61bother with housekeeping. klog and relay-app can be used together,
62with klog providing high-level logging functions to the kernel and
63relay-app taking care of kernel-user control and disk-logging chores.
64
65It is possible to use relayfs without relay-app & librelay, but you'll
66have to implement communication between userspace and kernel, allowing
67both to convey the state of buffers (full, empty, amount of padding).
68
69klog, relay-app and librelay can be found in the relay-apps tarball on
70http://relayfs.sourceforge.net
71
72The relayfs user space API
73==========================
74
75relayfs implements basic file operations for user space access to
76relayfs channel buffer data. Here are the file operations that are
77available and some comments regarding their behavior:
78
79open() enables user to open an _existing_ buffer.
80
81mmap() results in channel buffer being mapped into the caller's
82 memory space. Note that you can't do a partial mmap - you must
83 map the entire file, which is NRBUF * SUBBUFSIZE.
84
85read() read the contents of a channel buffer. The bytes read are
86 'consumed' by the reader i.e. they won't be available again
87 to subsequent reads. If the channel is being used in
88 no-overwrite mode (the default), it can be read at any time
89 even if there's an active kernel writer. If the channel is
90 being used in overwrite mode and there are active channel
91 writers, results may be unpredictable - users should make
92 sure that all logging to the channel has ended before using
93 read() with overwrite mode.
94
95poll() POLLIN/POLLRDNORM/POLLERR supported. User applications are
96 notified when sub-buffer boundaries are crossed.
97
98close() decrements the channel buffer's refcount. When the refcount
99 reaches 0 i.e. when no process or kernel client has the buffer
100 open, the channel buffer is freed.
101
102
103In order for a user application to make use of relayfs files, the
104relayfs filesystem must be mounted. For example,
105
106 mount -t relayfs relayfs /mnt/relay
107
108NOTE: relayfs doesn't need to be mounted for kernel clients to create
109 or use channels - it only needs to be mounted when user space
110 applications need access to the buffer data.
111
112
113The relayfs kernel API
114======================
115
116Here's a summary of the API relayfs provides to in-kernel clients:
117
118
119 channel management functions:
120
121 relay_open(base_filename, parent, subbuf_size, n_subbufs,
122 callbacks)
123 relay_close(chan)
124 relay_flush(chan)
125 relay_reset(chan)
126 relayfs_create_dir(name, parent)
127 relayfs_remove_dir(dentry)
128
129 channel management typically called on instigation of userspace:
130
131 relay_subbufs_consumed(chan, cpu, subbufs_consumed)
132
133 write functions:
134
135 relay_write(chan, data, length)
136 __relay_write(chan, data, length)
137 relay_reserve(chan, length)
138
139 callbacks:
140
141 subbuf_start(buf, subbuf, prev_subbuf, prev_padding)
142 buf_mapped(buf, filp)
143 buf_unmapped(buf, filp)
144
145 helper functions:
146
147 relay_buf_full(buf)
148 subbuf_start_reserve(buf, length)
149
150
151Creating a channel
152------------------
153
154relay_open() is used to create a channel, along with its per-cpu
155channel buffers. Each channel buffer will have an associated file
156created for it in the relayfs filesystem, which can be opened and
157mmapped from user space if desired. The files are named
158basename0...basenameN-1 where N is the number of online cpus, and by
159default will be created in the root of the filesystem. If you want a
160directory structure to contain your relayfs files, you can create it
161with relayfs_create_dir() and pass the parent directory to
162relay_open(). Clients are responsible for cleaning up any directory
163structure they create when the channel is closed - use
164relayfs_remove_dir() for that.
165
166The total size of each per-cpu buffer is calculated by multiplying the
167number of sub-buffers by the sub-buffer size passed into relay_open().
168The idea behind sub-buffers is that they're basically an extension of
169double-buffering to N buffers, and they also allow applications to
170easily implement random-access-on-buffer-boundary schemes, which can
171be important for some high-volume applications. The number and size
172of sub-buffers is completely dependent on the application and even for
173the same application, different conditions will warrant different
174values for these parameters at different times. Typically, the right
175values to use are best decided after some experimentation; in general,
176though, it's safe to assume that having only 1 sub-buffer is a bad
177idea - you're guaranteed to either overwrite data or lose events
178depending on the channel mode being used.
179
180Channel 'modes'
181---------------
182
183relayfs channels can be used in either of two modes - 'overwrite' or
184'no-overwrite'. The mode is entirely determined by the implementation
185of the subbuf_start() callback, as described below. In 'overwrite'
186mode, also known as 'flight recorder' mode, writes continuously cycle
187around the buffer and will never fail, but will unconditionally
188overwrite old data regardless of whether it's actually been consumed.
189In no-overwrite mode, writes will fail i.e. data will be lost, if the
190number of unconsumed sub-buffers equals the total number of
191sub-buffers in the channel. It should be clear that if there is no
192consumer or if the consumer can't consume sub-buffers fast enought,
193data will be lost in either case; the only difference is whether data
194is lost from the beginning or the end of a buffer.
195
196As explained above, a relayfs channel is made of up one or more
197per-cpu channel buffers, each implemented as a circular buffer
198subdivided into one or more sub-buffers. Messages are written into
199the current sub-buffer of the channel's current per-cpu buffer via the
200write functions described below. Whenever a message can't fit into
201the current sub-buffer, because there's no room left for it, the
202client is notified via the subbuf_start() callback that a switch to a
203new sub-buffer is about to occur. The client uses this callback to 1)
204initialize the next sub-buffer if appropriate 2) finalize the previous
205sub-buffer if appropriate and 3) return a boolean value indicating
206whether or not to actually go ahead with the sub-buffer switch.
207
208To implement 'no-overwrite' mode, the userspace client would provide
209an implementation of the subbuf_start() callback something like the
210following:
211
212static int subbuf_start(struct rchan_buf *buf,
213 void *subbuf,
214 void *prev_subbuf,
215 unsigned int prev_padding)
216{
217 if (prev_subbuf)
218 *((unsigned *)prev_subbuf) = prev_padding;
219
220 if (relay_buf_full(buf))
221 return 0;
222
223 subbuf_start_reserve(buf, sizeof(unsigned int));
224
225 return 1;
226}
227
228If the current buffer is full i.e. all sub-buffers remain unconsumed,
229the callback returns 0 to indicate that the buffer switch should not
230occur yet i.e. until the consumer has had a chance to read the current
231set of ready sub-buffers. For the relay_buf_full() function to make
232sense, the consumer is reponsible for notifying relayfs when
233sub-buffers have been consumed via relay_subbufs_consumed(). Any
234subsequent attempts to write into the buffer will again invoke the
235subbuf_start() callback with the same parameters; only when the
236consumer has consumed one or more of the ready sub-buffers will
237relay_buf_full() return 0, in which case the buffer switch can
238continue.
239
240The implementation of the subbuf_start() callback for 'overwrite' mode
241would be very similar:
242
243static int subbuf_start(struct rchan_buf *buf,
244 void *subbuf,
245 void *prev_subbuf,
246 unsigned int prev_padding)
247{
248 if (prev_subbuf)
249 *((unsigned *)prev_subbuf) = prev_padding;
250
251 subbuf_start_reserve(buf, sizeof(unsigned int));
252
253 return 1;
254}
255
256In this case, the relay_buf_full() check is meaningless and the
257callback always returns 1, causing the buffer switch to occur
258unconditionally. It's also meaningless for the client to use the
259relay_subbufs_consumed() function in this mode, as it's never
260consulted.
261
262The default subbuf_start() implementation, used if the client doesn't
263define any callbacks, or doesn't define the subbuf_start() callback,
264implements the simplest possible 'no-overwrite' mode i.e. it does
265nothing but return 0.
266
267Header information can be reserved at the beginning of each sub-buffer
268by calling the subbuf_start_reserve() helper function from within the
269subbuf_start() callback. This reserved area can be used to store
270whatever information the client wants. In the example above, room is
271reserved in each sub-buffer to store the padding count for that
272sub-buffer. This is filled in for the previous sub-buffer in the
273subbuf_start() implementation; the padding value for the previous
274sub-buffer is passed into the subbuf_start() callback along with a
275pointer to the previous sub-buffer, since the padding value isn't
276known until a sub-buffer is filled. The subbuf_start() callback is
277also called for the first sub-buffer when the channel is opened, to
278give the client a chance to reserve space in it. In this case the
279previous sub-buffer pointer passed into the callback will be NULL, so
280the client should check the value of the prev_subbuf pointer before
281writing into the previous sub-buffer.
282
283Writing to a channel
284--------------------
285
286kernel clients write data into the current cpu's channel buffer using
287relay_write() or __relay_write(). relay_write() is the main logging
288function - it uses local_irqsave() to protect the buffer and should be
289used if you might be logging from interrupt context. If you know
290you'll never be logging from interrupt context, you can use
291__relay_write(), which only disables preemption. These functions
292don't return a value, so you can't determine whether or not they
293failed - the assumption is that you wouldn't want to check a return
294value in the fast logging path anyway, and that they'll always succeed
295unless the buffer is full and no-overwrite mode is being used, in
296which case you can detect a failed write in the subbuf_start()
297callback by calling the relay_buf_full() helper function.
298
299relay_reserve() is used to reserve a slot in a channel buffer which
300can be written to later. This would typically be used in applications
301that need to write directly into a channel buffer without having to
302stage data in a temporary buffer beforehand. Because the actual write
303may not happen immediately after the slot is reserved, applications
304using relay_reserve() can keep a count of the number of bytes actually
305written, either in space reserved in the sub-buffers themselves or as
306a separate array. See the 'reserve' example in the relay-apps tarball
307at http://relayfs.sourceforge.net for an example of how this can be
308done. Because the write is under control of the client and is
309separated from the reserve, relay_reserve() doesn't protect the buffer
310at all - it's up to the client to provide the appropriate
311synchronization when using relay_reserve().
312
313Closing a channel
314-----------------
315
316The client calls relay_close() when it's finished using the channel.
317The channel and its associated buffers are destroyed when there are no
318longer any references to any of the channel buffers. relay_flush()
319forces a sub-buffer switch on all the channel buffers, and can be used
320to finalize and process the last sub-buffers before the channel is
321closed.
322
323Misc
324----
325
326Some applications may want to keep a channel around and re-use it
327rather than open and close a new channel for each use. relay_reset()
328can be used for this purpose - it resets a channel to its initial
329state without reallocating channel buffer memory or destroying
330existing mappings. It should however only be called when it's safe to
331do so i.e. when the channel isn't currently being written to.
332
333Finally, there are a couple of utility callbacks that can be used for
334different purposes. buf_mapped() is called whenever a channel buffer
335is mmapped from user space and buf_unmapped() is called when it's
336unmapped. The client can use this notification to trigger actions
337within the kernel application, such as enabling/disabling logging to
338the channel.
339
340
341Resources
342=========
343
344For news, example code, mailing list, etc. see the relayfs homepage:
345
346 http://relayfs.sourceforge.net
347
348
349Credits
350=======
351
352The ideas and specs for relayfs came about as a result of discussions
353on tracing involving the following:
354
355Michel Dagenais <michel.dagenais@polymtl.ca>
356Richard Moore <richardj_moore@uk.ibm.com>
357Bob Wisniewski <bob@watson.ibm.com>
358Karim Yaghmour <karim@opersys.com>
359Tom Zanussi <zanussi@us.ibm.com>
360
361Also thanks to Hubertus Franke for a lot of useful suggestions and bug
362reports.
diff --git a/Documentation/i386/boot.txt b/Documentation/i386/boot.txt
index 1c48f0eba6fb..10312bebe55d 100644
--- a/Documentation/i386/boot.txt
+++ b/Documentation/i386/boot.txt
@@ -2,7 +2,7 @@
2 ---------------------------- 2 ----------------------------
3 3
4 H. Peter Anvin <hpa@zytor.com> 4 H. Peter Anvin <hpa@zytor.com>
5 Last update 2002-01-01 5 Last update 2005-09-02
6 6
7On the i386 platform, the Linux kernel uses a rather complicated boot 7On the i386 platform, the Linux kernel uses a rather complicated boot
8convention. This has evolved partially due to historical aspects, as 8convention. This has evolved partially due to historical aspects, as
@@ -34,6 +34,8 @@ Protocol 2.02: (Kernel 2.4.0-test3-pre3) New command line protocol.
34Protocol 2.03: (Kernel 2.4.18-pre1) Explicitly makes the highest possible 34Protocol 2.03: (Kernel 2.4.18-pre1) Explicitly makes the highest possible
35 initrd address available to the bootloader. 35 initrd address available to the bootloader.
36 36
37Protocol 2.04: (Kernel 2.6.14) Extend the syssize field to four bytes.
38
37 39
38**** MEMORY LAYOUT 40**** MEMORY LAYOUT
39 41
@@ -103,10 +105,9 @@ The header looks like:
103Offset Proto Name Meaning 105Offset Proto Name Meaning
104/Size 106/Size
105 107
10601F1/1 ALL setup_sects The size of the setup in sectors 10801F1/1 ALL(1 setup_sects The size of the setup in sectors
10701F2/2 ALL root_flags If set, the root is mounted readonly 10901F2/2 ALL root_flags If set, the root is mounted readonly
10801F4/2 ALL syssize DO NOT USE - for bootsect.S use only 11001F4/4 2.04+(2 syssize The size of the 32-bit code in 16-byte paras
10901F6/2 ALL swap_dev DO NOT USE - obsolete
11001F8/2 ALL ram_size DO NOT USE - for bootsect.S use only 11101F8/2 ALL ram_size DO NOT USE - for bootsect.S use only
11101FA/2 ALL vid_mode Video mode control 11201FA/2 ALL vid_mode Video mode control
11201FC/2 ALL root_dev Default root device number 11301FC/2 ALL root_dev Default root device number
@@ -129,8 +130,12 @@ Offset Proto Name Meaning
1290228/4 2.02+ cmd_line_ptr 32-bit pointer to the kernel command line 1300228/4 2.02+ cmd_line_ptr 32-bit pointer to the kernel command line
130022C/4 2.03+ initrd_addr_max Highest legal initrd address 131022C/4 2.03+ initrd_addr_max Highest legal initrd address
131 132
132For backwards compatibility, if the setup_sects field contains 0, the 133(1) For backwards compatibility, if the setup_sects field contains 0, the
133real value is 4. 134 real value is 4.
135
136(2) For boot protocol prior to 2.04, the upper two bytes of the syssize
137 field are unusable, which means the size of a bzImage kernel
138 cannot be determined.
134 139
135If the "HdrS" (0x53726448) magic number is not found at offset 0x202, 140If the "HdrS" (0x53726448) magic number is not found at offset 0x202,
136the boot protocol version is "old". Loading an old kernel, the 141the boot protocol version is "old". Loading an old kernel, the
@@ -230,12 +235,16 @@ loader to communicate with the kernel. Some of its options are also
230relevant to the boot loader itself, see "special command line options" 235relevant to the boot loader itself, see "special command line options"
231below. 236below.
232 237
233The kernel command line is a null-terminated string up to 255 238The kernel command line is a null-terminated string currently up to
234characters long, plus the final null. 239255 characters long, plus the final null. A string that is too long
240will be automatically truncated by the kernel, a boot loader may allow
241a longer command line to be passed to permit future kernels to extend
242this limit.
235 243
236If the boot protocol version is 2.02 or later, the address of the 244If the boot protocol version is 2.02 or later, the address of the
237kernel command line is given by the header field cmd_line_ptr (see 245kernel command line is given by the header field cmd_line_ptr (see
238above.) 246above.) This address can be anywhere between the end of the setup
247heap and 0xA0000.
239 248
240If the protocol version is *not* 2.02 or higher, the kernel 249If the protocol version is *not* 2.02 or higher, the kernel
241command line is entered using the following protocol: 250command line is entered using the following protocol:
@@ -255,7 +264,7 @@ command line is entered using the following protocol:
255**** SAMPLE BOOT CONFIGURATION 264**** SAMPLE BOOT CONFIGURATION
256 265
257As a sample configuration, assume the following layout of the real 266As a sample configuration, assume the following layout of the real
258mode segment: 267mode segment (this is a typical, and recommended layout):
259 268
260 0x0000-0x7FFF Real mode kernel 269 0x0000-0x7FFF Real mode kernel
261 0x8000-0x8FFF Stack and heap 270 0x8000-0x8FFF Stack and heap
@@ -312,9 +321,9 @@ Such a boot loader should enter the following fields in the header:
312 321
313**** LOADING THE REST OF THE KERNEL 322**** LOADING THE REST OF THE KERNEL
314 323
315The non-real-mode kernel starts at offset (setup_sects+1)*512 in the 324The 32-bit (non-real-mode) kernel starts at offset (setup_sects+1)*512
316kernel file (again, if setup_sects == 0 the real value is 4.) It 325in the kernel file (again, if setup_sects == 0 the real value is 4.)
317should be loaded at address 0x10000 for Image/zImage kernels and 326It should be loaded at address 0x10000 for Image/zImage kernels and
3180x100000 for bzImage kernels. 3270x100000 for bzImage kernels.
319 328
320The kernel is a bzImage kernel if the protocol >= 2.00 and the 0x01 329The kernel is a bzImage kernel if the protocol >= 2.00 and the 0x01
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 3d5cd7a09b2f..d2f0c67ba1fb 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1174,6 +1174,11 @@ running once the system is up.
1174 New name for the ramdisk parameter. 1174 New name for the ramdisk parameter.
1175 See Documentation/ramdisk.txt. 1175 See Documentation/ramdisk.txt.
1176 1176
1177 rdinit= [KNL]
1178 Format: <full_path>
1179 Run specified binary instead of /init from the ramdisk,
1180 used for early userspace startup. See initrd.
1181
1177 reboot= [BUGS=IA-32,BUGS=ARM,BUGS=IA-64] Rebooting mode 1182 reboot= [BUGS=IA-32,BUGS=ARM,BUGS=IA-64] Rebooting mode
1178 Format: <reboot_mode>[,<reboot_mode2>[,...]] 1183 Format: <reboot_mode>[,<reboot_mode2>[,...]]
1179 See arch/*/kernel/reboot.c. 1184 See arch/*/kernel/reboot.c.
diff --git a/Documentation/power/swsusp.txt b/Documentation/power/swsusp.txt
index ddf907fbcc05..b0d50840788e 100644
--- a/Documentation/power/swsusp.txt
+++ b/Documentation/power/swsusp.txt
@@ -1,22 +1,20 @@
1From kernel/suspend.c: 1Some warnings, first.
2 2
3 * BIG FAT WARNING ********************************************************* 3 * BIG FAT WARNING *********************************************************
4 * 4 *
5 * If you have unsupported (*) devices using DMA...
6 * ...say goodbye to your data.
7 *
8 * If you touch anything on disk between suspend and resume... 5 * If you touch anything on disk between suspend and resume...
9 * ...kiss your data goodbye. 6 * ...kiss your data goodbye.
10 * 7 *
11 * If your disk driver does not support suspend... (IDE does) 8 * If you do resume from initrd after your filesystems are mounted...
12 * ...you'd better find out how to get along 9 * ...bye bye root partition.
13 * without your data. 10 * [this is actually same case as above]
14 *
15 * If you change kernel command line between suspend and resume...
16 * ...prepare for nasty fsck or worse.
17 * 11 *
18 * If you change your hardware while system is suspended... 12 * If you have unsupported (*) devices using DMA, you may have some
19 * ...well, it was not good idea. 13 * problems. If your disk driver does not support suspend... (IDE does),
14 * it may cause some problems, too. If you change kernel command line
15 * between suspend and resume, it may do something wrong. If you change
16 * your hardware while system is suspended... well, it was not good idea;
17 * but it will probably only crash.
20 * 18 *
21 * (*) suspend/resume support is needed to make it safe. 19 * (*) suspend/resume support is needed to make it safe.
22 20
@@ -30,6 +28,13 @@ echo shutdown > /sys/power/disk; echo disk > /sys/power/state
30echo platform > /sys/power/disk; echo disk > /sys/power/state 28echo platform > /sys/power/disk; echo disk > /sys/power/state
31 29
32 30
31Encrypted suspend image:
32------------------------
33If you want to store your suspend image encrypted with a temporary
34key to prevent data gathering after resume you must compile
35crypto and the aes algorithm into the kernel - modules won't work
36as they cannot be loaded at resume time.
37
33 38
34Article about goals and implementation of Software Suspend for Linux 39Article about goals and implementation of Software Suspend for Linux
35~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 40~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -85,11 +90,6 @@ resume.
85You have your server on UPS. Power died, and UPS is indicating 30 90You have your server on UPS. Power died, and UPS is indicating 30
86seconds to failure. What do you do? Suspend to disk. 91seconds to failure. What do you do? Suspend to disk.
87 92
88Ethernet card in your server died. You want to replace it. Your
89server is not hotplug capable. What do you do? Suspend to disk,
90replace ethernet card, resume. If you are fast your users will not
91even see broken connections.
92
93 93
94Q: Maybe I'm missing something, but why don't the regular I/O paths work? 94Q: Maybe I'm missing something, but why don't the regular I/O paths work?
95 95
@@ -117,31 +117,6 @@ Q: Does linux support ACPI S4?
117 117
118A: Yes. That's what echo platform > /sys/power/disk does. 118A: Yes. That's what echo platform > /sys/power/disk does.
119 119
120Q: My machine doesn't work with ACPI. How can I use swsusp than ?
121
122A: Do a reboot() syscall with right parameters. Warning: glibc gets in
123its way, so check with strace:
124
125reboot(LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2, 0xd000fce2)
126
127(Thanks to Peter Osterlund:)
128
129#include <unistd.h>
130#include <syscall.h>
131
132#define LINUX_REBOOT_MAGIC1 0xfee1dead
133#define LINUX_REBOOT_MAGIC2 672274793
134#define LINUX_REBOOT_CMD_SW_SUSPEND 0xD000FCE2
135
136int main()
137{
138 syscall(SYS_reboot, LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2,
139 LINUX_REBOOT_CMD_SW_SUSPEND, 0);
140 return 0;
141}
142
143Also /sys/ interface should be still present.
144
145Q: What is 'suspend2'? 120Q: What is 'suspend2'?
146 121
147A: suspend2 is 'Software Suspend 2', a forked implementation of 122A: suspend2 is 'Software Suspend 2', a forked implementation of
@@ -312,9 +287,45 @@ system is shut down or suspended. Additionally use the encrypted
312suspend image to prevent sensitive data from being stolen after 287suspend image to prevent sensitive data from being stolen after
313resume. 288resume.
314 289
315Q: Why we cannot suspend to a swap file? 290Q: Why can't we suspend to a swap file?
316 291
317A: Because accessing swap file needs the filesystem mounted, and 292A: Because accessing swap file needs the filesystem mounted, and
318filesystem might do something wrong (like replaying the journal) 293filesystem might do something wrong (like replaying the journal)
319during mount. [Probably could be solved by modifying every filesystem 294during mount.
320to support some kind of "really read-only!" option. Patches welcome.] 295
296There are few ways to get that fixed:
297
2981) Probably could be solved by modifying every filesystem to support
299some kind of "really read-only!" option. Patches welcome.
300
3012) suspend2 gets around that by storing absolute positions in on-disk
302image (and blocksize), with resume parameter pointing directly to
303suspend header.
304
305Q: Is there a maximum system RAM size that is supported by swsusp?
306
307A: It should work okay with highmem.
308
309Q: Does swsusp (to disk) use only one swap partition or can it use
310multiple swap partitions (aggregate them into one logical space)?
311
312A: Only one swap partition, sorry.
313
314Q: If my application(s) causes lots of memory & swap space to be used
315(over half of the total system RAM), is it correct that it is likely
316to be useless to try to suspend to disk while that app is running?
317
318A: No, it should work okay, as long as your app does not mlock()
319it. Just prepare big enough swap partition.
320
321Q: What information is usefull for debugging suspend-to-disk problems?
322
323A: Well, last messages on the screen are always useful. If something
324is broken, it is usually some kernel driver, therefore trying with as
325little as possible modules loaded helps a lot. I also prefer people to
326suspend from console, preferably without X running. Booting with
327init=/bin/bash, then swapon and starting suspend sequence manually
328usually does the trick. Then it is good idea to try with latest
329vanilla kernel.
330
331
diff --git a/Documentation/power/video.txt b/Documentation/power/video.txt
index 1a44e8acb54c..526d6dd267ea 100644
--- a/Documentation/power/video.txt
+++ b/Documentation/power/video.txt
@@ -120,6 +120,7 @@ IBM ThinkPad T42p (2373-GTG) s3_bios (2)
120IBM TP X20 ??? (*) 120IBM TP X20 ??? (*)
121IBM TP X30 s3_bios (2) 121IBM TP X30 s3_bios (2)
122IBM TP X31 / Type 2672-XXH none (1), use radeontool (http://fdd.com/software/radeon/) to turn off backlight. 122IBM TP X31 / Type 2672-XXH none (1), use radeontool (http://fdd.com/software/radeon/) to turn off backlight.
123IBM TP X32 none (1), but backlight is on and video is trashed after long suspend
123IBM Thinkpad X40 Type 2371-7JG s3_bios,s3_mode (4) 124IBM Thinkpad X40 Type 2371-7JG s3_bios,s3_mode (4)
124Medion MD4220 ??? (*) 125Medion MD4220 ??? (*)
125Samsung P35 vbetool needed (6) 126Samsung P35 vbetool needed (6)
diff --git a/Documentation/sonypi.txt b/Documentation/sonypi.txt
index 0f3b2405d09e..c1237a925505 100644
--- a/Documentation/sonypi.txt
+++ b/Documentation/sonypi.txt
@@ -99,6 +99,7 @@ statically linked into the kernel). Those options are:
99 SONYPI_MEYE_MASK 0x0400 99 SONYPI_MEYE_MASK 0x0400
100 SONYPI_MEMORYSTICK_MASK 0x0800 100 SONYPI_MEMORYSTICK_MASK 0x0800
101 SONYPI_BATTERY_MASK 0x1000 101 SONYPI_BATTERY_MASK 0x1000
102 SONYPI_WIRELESS_MASK 0x2000
102 103
103 useinput: if set (which is the default) two input devices are 104 useinput: if set (which is the default) two input devices are
104 created, one which interprets the jogdial events as 105 created, one which interprets the jogdial events as
@@ -137,6 +138,15 @@ Bugs:
137 speed handling etc). Use ACPI instead of APM if it works on your 138 speed handling etc). Use ACPI instead of APM if it works on your
138 laptop. 139 laptop.
139 140
141 - sonypi lacks the ability to distinguish between certain key
142 events on some models.
143
144 - some models with the nvidia card (geforce go 6200 tc) uses a
145 different way to adjust the backlighting of the screen. There
146 is a userspace utility to adjust the brightness on those models,
147 which can be downloaded from
148 http://www.acc.umu.se/~erikw/program/smartdimmer-0.1.tar.bz2
149
140 - since all development was done by reverse engineering, there is 150 - since all development was done by reverse engineering, there is
141 _absolutely no guarantee_ that this driver will not crash your 151 _absolutely no guarantee_ that this driver will not crash your
142 laptop. Permanently. 152 laptop. Permanently.