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-rw-r--r--Documentation/DocBook/device-drivers.tmpl12
-rw-r--r--Documentation/IRQ-domain.txt117
-rw-r--r--Documentation/input/event-codes.txt72
-rw-r--r--Documentation/sysctl/kernel.txt2
4 files changed, 193 insertions, 10 deletions
diff --git a/Documentation/DocBook/device-drivers.tmpl b/Documentation/DocBook/device-drivers.tmpl
index 2f7fd4360848..9c27e5125dd2 100644
--- a/Documentation/DocBook/device-drivers.tmpl
+++ b/Documentation/DocBook/device-drivers.tmpl
@@ -102,9 +102,12 @@ X!Iinclude/linux/kobject.h
102!Iinclude/linux/device.h 102!Iinclude/linux/device.h
103 </sect1> 103 </sect1>
104 <sect1><title>Device Drivers Base</title> 104 <sect1><title>Device Drivers Base</title>
105!Idrivers/base/init.c
105!Edrivers/base/driver.c 106!Edrivers/base/driver.c
106!Edrivers/base/core.c 107!Edrivers/base/core.c
108!Edrivers/base/syscore.c
107!Edrivers/base/class.c 109!Edrivers/base/class.c
110!Idrivers/base/node.c
108!Edrivers/base/firmware_class.c 111!Edrivers/base/firmware_class.c
109!Edrivers/base/transport_class.c 112!Edrivers/base/transport_class.c
110<!-- Cannot be included, because 113<!-- Cannot be included, because
@@ -113,7 +116,7 @@ X!Iinclude/linux/kobject.h
113 exceed allowed 44 characters maximum 116 exceed allowed 44 characters maximum
114X!Edrivers/base/attribute_container.c 117X!Edrivers/base/attribute_container.c
115--> 118-->
116!Edrivers/base/sys.c 119!Edrivers/base/dd.c
117<!-- 120<!--
118X!Edrivers/base/interface.c 121X!Edrivers/base/interface.c
119--> 122-->
@@ -121,6 +124,11 @@ X!Edrivers/base/interface.c
121!Edrivers/base/platform.c 124!Edrivers/base/platform.c
122!Edrivers/base/bus.c 125!Edrivers/base/bus.c
123 </sect1> 126 </sect1>
127 <sect1><title>Device Drivers DMA Management</title>
128!Edrivers/base/dma-buf.c
129!Edrivers/base/dma-coherent.c
130!Edrivers/base/dma-mapping.c
131 </sect1>
124 <sect1><title>Device Drivers Power Management</title> 132 <sect1><title>Device Drivers Power Management</title>
125!Edrivers/base/power/main.c 133!Edrivers/base/power/main.c
126 </sect1> 134 </sect1>
@@ -219,7 +227,7 @@ X!Isound/sound_firmware.c
219 <chapter id="uart16x50"> 227 <chapter id="uart16x50">
220 <title>16x50 UART Driver</title> 228 <title>16x50 UART Driver</title>
221!Edrivers/tty/serial/serial_core.c 229!Edrivers/tty/serial/serial_core.c
222!Edrivers/tty/serial/8250.c 230!Edrivers/tty/serial/8250/8250.c
223 </chapter> 231 </chapter>
224 232
225 <chapter id="fbdev"> 233 <chapter id="fbdev">
diff --git a/Documentation/IRQ-domain.txt b/Documentation/IRQ-domain.txt
new file mode 100644
index 000000000000..27dcaabfb4db
--- /dev/null
+++ b/Documentation/IRQ-domain.txt
@@ -0,0 +1,117 @@
1irq_domain interrupt number mapping library
2
3The current design of the Linux kernel uses a single large number
4space where each separate IRQ source is assigned a different number.
5This is simple when there is only one interrupt controller, but in
6systems with multiple interrupt controllers the kernel must ensure
7that each one gets assigned non-overlapping allocations of Linux
8IRQ numbers.
9
10The irq_alloc_desc*() and irq_free_desc*() APIs provide allocation of
11irq numbers, but they don't provide any support for reverse mapping of
12the controller-local IRQ (hwirq) number into the Linux IRQ number
13space.
14
15The irq_domain library adds mapping between hwirq and IRQ numbers on
16top of the irq_alloc_desc*() API. An irq_domain to manage mapping is
17preferred over interrupt controller drivers open coding their own
18reverse mapping scheme.
19
20irq_domain also implements translation from Device Tree interrupt
21specifiers to hwirq numbers, and can be easily extended to support
22other IRQ topology data sources.
23
24=== irq_domain usage ===
25An interrupt controller driver creates and registers an irq_domain by
26calling one of the irq_domain_add_*() functions (each mapping method
27has a different allocator function, more on that later). The function
28will return a pointer to the irq_domain on success. The caller must
29provide the allocator function with an irq_domain_ops structure with
30the .map callback populated as a minimum.
31
32In most cases, the irq_domain will begin empty without any mappings
33between hwirq and IRQ numbers. Mappings are added to the irq_domain
34by calling irq_create_mapping() which accepts the irq_domain and a
35hwirq number as arguments. If a mapping for the hwirq doesn't already
36exist then it will allocate a new Linux irq_desc, associate it with
37the hwirq, and call the .map() callback so the driver can perform any
38required hardware setup.
39
40When an interrupt is received, irq_find_mapping() function should
41be used to find the Linux IRQ number from the hwirq number.
42
43If the driver has the Linux IRQ number or the irq_data pointer, and
44needs to know the associated hwirq number (such as in the irq_chip
45callbacks) then it can be directly obtained from irq_data->hwirq.
46
47=== Types of irq_domain mappings ===
48There are several mechanisms available for reverse mapping from hwirq
49to Linux irq, and each mechanism uses a different allocation function.
50Which reverse map type should be used depends on the use case. Each
51of the reverse map types are described below:
52
53==== Linear ====
54irq_domain_add_linear()
55
56The linear reverse map maintains a fixed size table indexed by the
57hwirq number. When a hwirq is mapped, an irq_desc is allocated for
58the hwirq, and the IRQ number is stored in the table.
59
60The Linear map is a good choice when the maximum number of hwirqs is
61fixed and a relatively small number (~ < 256). The advantages of this
62map are fixed time lookup for IRQ numbers, and irq_descs are only
63allocated for in-use IRQs. The disadvantage is that the table must be
64as large as the largest possible hwirq number.
65
66The majority of drivers should use the linear map.
67
68==== Tree ====
69irq_domain_add_tree()
70
71The irq_domain maintains a radix tree map from hwirq numbers to Linux
72IRQs. When an hwirq is mapped, an irq_desc is allocated and the
73hwirq is used as the lookup key for the radix tree.
74
75The tree map is a good choice if the hwirq number can be very large
76since it doesn't need to allocate a table as large as the largest
77hwirq number. The disadvantage is that hwirq to IRQ number lookup is
78dependent on how many entries are in the table.
79
80Very few drivers should need this mapping. At the moment, powerpc
81iseries is the only user.
82
83==== No Map ===-
84irq_domain_add_nomap()
85
86The No Map mapping is to be used when the hwirq number is
87programmable in the hardware. In this case it is best to program the
88Linux IRQ number into the hardware itself so that no mapping is
89required. Calling irq_create_direct_mapping() will allocate a Linux
90IRQ number and call the .map() callback so that driver can program the
91Linux IRQ number into the hardware.
92
93Most drivers cannot use this mapping.
94
95==== Legacy ====
96irq_domain_add_legacy()
97irq_domain_add_legacy_isa()
98
99The Legacy mapping is a special case for drivers that already have a
100range of irq_descs allocated for the hwirqs. It is used when the
101driver cannot be immediately converted to use the linear mapping. For
102example, many embedded system board support files use a set of #defines
103for IRQ numbers that are passed to struct device registrations. In that
104case the Linux IRQ numbers cannot be dynamically assigned and the legacy
105mapping should be used.
106
107The legacy map assumes a contiguous range of IRQ numbers has already
108been allocated for the controller and that the IRQ number can be
109calculated by adding a fixed offset to the hwirq number, and
110visa-versa. The disadvantage is that it requires the interrupt
111controller to manage IRQ allocations and it requires an irq_desc to be
112allocated for every hwirq, even if it is unused.
113
114The legacy map should only be used if fixed IRQ mappings must be
115supported. For example, ISA controllers would use the legacy map for
116mapping Linux IRQs 0-15 so that existing ISA drivers get the correct IRQ
117numbers.
diff --git a/Documentation/input/event-codes.txt b/Documentation/input/event-codes.txt
index 23fcb05175be..53305bd08182 100644
--- a/Documentation/input/event-codes.txt
+++ b/Documentation/input/event-codes.txt
@@ -17,11 +17,11 @@ reports supported by a device are also provided by sysfs in
17class/input/event*/device/capabilities/, and the properties of a device are 17class/input/event*/device/capabilities/, and the properties of a device are
18provided in class/input/event*/device/properties. 18provided in class/input/event*/device/properties.
19 19
20Types: 20Event types:
21========== 21===========
22Types are groupings of codes under a logical input construct. Each type has a 22Event types are groupings of codes under a logical input construct. Each
23set of applicable codes to be used in generating events. See the Codes section 23type has a set of applicable codes to be used in generating events. See the
24for details on valid codes for each type. 24Codes section for details on valid codes for each type.
25 25
26* EV_SYN: 26* EV_SYN:
27 - Used as markers to separate events. Events may be separated in time or in 27 - Used as markers to separate events. Events may be separated in time or in
@@ -63,9 +63,9 @@ for details on valid codes for each type.
63* EV_FF_STATUS: 63* EV_FF_STATUS:
64 - Used to receive force feedback device status. 64 - Used to receive force feedback device status.
65 65
66Codes: 66Event codes:
67========== 67===========
68Codes define the precise type of event. 68Event codes define the precise type of event.
69 69
70EV_SYN: 70EV_SYN:
71---------- 71----------
@@ -220,6 +220,56 @@ EV_PWR:
220EV_PWR events are a special type of event used specifically for power 220EV_PWR events are a special type of event used specifically for power
221mangement. Its usage is not well defined. To be addressed later. 221mangement. Its usage is not well defined. To be addressed later.
222 222
223Device properties:
224=================
225Normally, userspace sets up an input device based on the data it emits,
226i.e., the event types. In the case of two devices emitting the same event
227types, additional information can be provided in the form of device
228properties.
229
230INPUT_PROP_DIRECT + INPUT_PROP_POINTER:
231--------------------------------------
232The INPUT_PROP_DIRECT property indicates that device coordinates should be
233directly mapped to screen coordinates (not taking into account trivial
234transformations, such as scaling, flipping and rotating). Non-direct input
235devices require non-trivial transformation, such as absolute to relative
236transformation for touchpads. Typical direct input devices: touchscreens,
237drawing tablets; non-direct devices: touchpads, mice.
238
239The INPUT_PROP_POINTER property indicates that the device is not transposed
240on the screen and thus requires use of an on-screen pointer to trace user's
241movements. Typical pointer devices: touchpads, tablets, mice; non-pointer
242device: touchscreen.
243
244If neither INPUT_PROP_DIRECT or INPUT_PROP_POINTER are set, the property is
245considered undefined and the device type should be deduced in the
246traditional way, using emitted event types.
247
248INPUT_PROP_BUTTONPAD:
249--------------------
250For touchpads where the button is placed beneath the surface, such that
251pressing down on the pad causes a button click, this property should be
252set. Common in clickpad notebooks and macbooks from 2009 and onwards.
253
254Originally, the buttonpad property was coded into the bcm5974 driver
255version field under the name integrated button. For backwards
256compatibility, both methods need to be checked in userspace.
257
258INPUT_PROP_SEMI_MT:
259------------------
260Some touchpads, most common between 2008 and 2011, can detect the presence
261of multiple contacts without resolving the individual positions; only the
262number of contacts and a rectangular shape is known. For such
263touchpads, the semi-mt property should be set.
264
265Depending on the device, the rectangle may enclose all touches, like a
266bounding box, or just some of them, for instance the two most recent
267touches. The diversity makes the rectangle of limited use, but some
268gestures can normally be extracted from it.
269
270If INPUT_PROP_SEMI_MT is not set, the device is assumed to be a true MT
271device.
272
223Guidelines: 273Guidelines:
224========== 274==========
225The guidelines below ensure proper single-touch and multi-finger functionality. 275The guidelines below ensure proper single-touch and multi-finger functionality.
@@ -240,6 +290,8 @@ used to report when a touch is active on the screen.
240BTN_{MOUSE,LEFT,MIDDLE,RIGHT} must not be reported as the result of touch 290BTN_{MOUSE,LEFT,MIDDLE,RIGHT} must not be reported as the result of touch
241contact. BTN_TOOL_<name> events should be reported where possible. 291contact. BTN_TOOL_<name> events should be reported where possible.
242 292
293For new hardware, INPUT_PROP_DIRECT should be set.
294
243Trackpads: 295Trackpads:
244---------- 296----------
245Legacy trackpads that only provide relative position information must report 297Legacy trackpads that only provide relative position information must report
@@ -250,6 +302,8 @@ location of the touch. BTN_TOUCH should be used to report when a touch is active
250on the trackpad. Where multi-finger support is available, BTN_TOOL_<name> should 302on the trackpad. Where multi-finger support is available, BTN_TOOL_<name> should
251be used to report the number of touches active on the trackpad. 303be used to report the number of touches active on the trackpad.
252 304
305For new hardware, INPUT_PROP_POINTER should be set.
306
253Tablets: 307Tablets:
254---------- 308----------
255BTN_TOOL_<name> events must be reported when a stylus or other tool is active on 309BTN_TOOL_<name> events must be reported when a stylus or other tool is active on
@@ -260,3 +314,5 @@ button may be used for buttons on the tablet except BTN_{MOUSE,LEFT}.
260BTN_{0,1,2,etc} are good generic codes for unlabeled buttons. Do not use 314BTN_{0,1,2,etc} are good generic codes for unlabeled buttons. Do not use
261meaningful buttons, like BTN_FORWARD, unless the button is labeled for that 315meaningful buttons, like BTN_FORWARD, unless the button is labeled for that
262purpose on the device. 316purpose on the device.
317
318For new hardware, both INPUT_PROP_DIRECT and INPUT_PROP_POINTER should be set.
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt
index 8c20fbd8b42d..6d78841fd416 100644
--- a/Documentation/sysctl/kernel.txt
+++ b/Documentation/sysctl/kernel.txt
@@ -601,6 +601,8 @@ can be ORed together:
601 instead of using the one provided by the hardware. 601 instead of using the one provided by the hardware.
602 512 - A kernel warning has occurred. 602 512 - A kernel warning has occurred.
6031024 - A module from drivers/staging was loaded. 6031024 - A module from drivers/staging was loaded.
6042048 - The system is working around a severe firmware bug.
6054096 - An out-of-tree module has been loaded.
604 606
605============================================================== 607==============================================================
606 608