Add HID classes #47
Add HID classes #47
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| # This is not reallyy a stand-alone descriptor, but it is part of the HIDDescriptor above. | ||
| # That descriptor can contain multiple ReportDescriptors. To support this, a seperate | ||
| # descriptor format is used. | ||
| HIDReportDescriptor = DescriptorFormat( | ||
| "bDescriptorType" / DescriptorField("HID Descriptor Type", default=HidClassSpecificDescriptorTypes.CS_REPORT), | ||
| "wDescriptorLength" / DescriptorField("HID Descriptor Length") | ||
| ) |
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This type should be called something other than HIDReportDescriptor, because:
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At some point we're going to want that name for the actual HID report descriptor (i.e. type
0x22). -
A report descriptor is not the only thing that can appear here. The other descriptors listed by the HID descriptor are usually report descriptors, but the HID spec also specifies physical descriptors (
0x23) that would appear here, and further types could be also be included in theory. As you note, this particular sub-format isn't really a descriptor. It's a reference to a descriptor that may be retrieved separately. So my suggestion for the name here would beHIDDescriptorReference.
| def ReportDescriptor(self): | ||
| """ Context manager that allows addition of a subordinate report descriptor. | ||
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| It can be used with a `with` statement; and yields an HIDReportDescriptorEmitter | ||
| that can be populated: | ||
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| with hiddescriptor.ReportDescriptor() as r: | ||
| r.wDescriptorLength = 0x10 | ||
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| This adds the relevant descriptor, automatically. | ||
| """ | ||
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| descriptor = HIDReportDescriptorEmitter() | ||
| yield descriptor |
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Similarly, I think ReportDescriptor should be changed to DescriptorReference throughout these lines.
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Good suggestion, applied it
Add support for HID class specific descriptors. This is different from #6, as it doesn't include the actual HID report itself. It is assumed that that is already known or created using a different tool.