Lines Matching full:report
4 Introduction to HID report descriptors
7 This chapter is meant to give a broad overview of what HID report
36 through the *HID report descriptor*, a fixed set of bytes describing
39 a HID Report Descriptor may specify that "in a report with ID 3 the
42 The HID report itself then merely carries the actual data values
48 The HID subsystem is in charge of parsing the HID report descriptors,
51 HID report descriptor provided by the device is wrong, or because it
55 The format of HID report descriptors is described by two documents,
66 Parsing HID report descriptors
71 one can read the corresponding report descriptor::
80 Optional: the HID report descriptor can be read also by
83 The basic structure of HID report descriptors is defined in the HID
86 HID report". Each entry is defined by at least two bytes, where the
91 HID report descriptors can, in principle, be painstakingly parsed by
96 if you need to patch HID report descriptors.
98 In practice you should not parse HID report descriptors by hand; rather,
105 (verbosity can be useful if you are not familiar with HID report
113 Parsing the mouse HID report descriptor with `hid-tools
139 # 0x75, 0x01, // Report Size (1) 20
143 # 0x95, 0x03, // Report Count (3) 22
153 # 0x75, 0x05, // Report Size (5) 26
157 # 0x95, 0x01, // Report Count (1) 28
178 # 0x75, 0x08, // Report Size (8) 44
182 # 0x95, 0x03, // Report Count (3) 46
189 the change from the previously sent report (event) ::
199 This Report Descriptor tells us that the mouse input will be
204 Indeed, for any event, the mouse will send a *report* of four bytes.
263 Collections, Report IDs and Evdev events
271 Different reports are identified by means of different *Report ID*
273 following report.
274 Whenever a Report ID is needed it is transmitted as the first byte of
275 any report. A device with only one supported HID report (like the mouse
276 example above) may omit the report ID.
278 Consider the following HID report descriptor::
301 respectively), a ``Keypad`` Application Collection (whose report is
302 identified by the Report ID 5) and two ``Consumer Controls`` Application
303 Collections, (with Report IDs 6 and 3, respectively). Note, however,
304 that a device can have different Report IDs for the same Application
307 The data sent will begin with the Report ID byte, and will be followed
314 0x85, 0x03, // Report ID (3)
318 0x75, 0x08, // Report Size (8)
319 0x95, 0x02, // Report Count (2)
323 will be of three bytes: the first for the Report ID (3), the next two
324 for the headphone, with two (``Report Count (2)``) bytes
325 (``Report Size (8)``), each ranging from 0 (``Logical Minimum (0)``)
420 * The HID report descriptor provided by the HID device may be wrong
424 will not able to make sense of the HID report descriptor;
425 * the HID report descriptor *does not match* what is actually
428 * the HID report descriptor may need some "quirks" (see later on).
458 Fixing HID report descriptors
461 Should you need to patch HID report descriptors the easiest way is to
464 Basically, you can change any byte of the original HID report
483 the HID report descriptor hex numbers.
514 Report Descriptor Size: 52
515 Report Descriptor: