9af6540381
A controller reaches a device by the path to it and, for a slow device, through the hub that translates for it. Neither was described, so a device behind a hub was addressed as though it were on the root port. The route string is that path: each hub between the device and the root contributes a nibble holding the port the next thing down occupies, tier nearest the root in the lowest nibble. Walking up from the device reaches the deepest tier first, so shifting left by a nibble each time leaves them in the order the field wants. The walk stops after five, which is what the field holds and what USB allows, and a port above fifteen is clamped. Slot context dword 2 names the transaction translator carrying a low or full speed device behind a high speed hub. It reports the hub by slot, where EHCI reports it by USB address, and it names the nearest high speed ancestor rather than the immediate parent, since a full speed hub below a high speed one is itself carried by the translator above it. The think time comes from the hub descriptor by way of the hub class driver, in the same units. xhci_epalloc() carried a copy of sam_ehci.c's block, writing epinfo->hubaddr and epinfo->hubport, which is how EHCI describes a split transaction in its queue head. This driver never read either field, and xHCI wants the information in the slot context. Both fields and the code setting them are removed. Multi-TT is not set, for the reason given in the previous commit. No functional change: hubs cannot be enabled yet, and a device on a root port has neither hubs above it nor a translator. Assisted-by: Claude:claude-opus-5 Signed-off-by: Justin Hammond <justin@dynam.ac> |
||
|---|---|---|
| .github | ||
| arch | ||
| audio | ||
| binfmt | ||
| boards | ||
| cmake | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| dummy | ||
| fs | ||
| graphics | ||
| include | ||
| libs | ||
| mm | ||
| net | ||
| openamp | ||
| pass1 | ||
| sched | ||
| syscall | ||
| tools | ||
| video | ||
| wireless | ||
| .asf.yaml | ||
| .codespell-ignore-lines | ||
| .codespellrc | ||
| .editorconfig | ||
| .gitignore | ||
| .gitmessage | ||
| .mcp.json | ||
| .pre-commit-config.yaml | ||
| .yamllint | ||
| AUTHORS | ||
| CMakeLists.txt | ||
| CONTRIBUTING.md | ||
| INVIOLABLES.md | ||
| Kconfig | ||
| LICENSE | ||
| Makefile | ||
| NOTICE | ||
| README.md | ||
| ReleaseNotes | ||
Apache NuttX is a real-time operating system (RTOS) with an emphasis on standards compliance and small footprint. Scalable from 8-bit to 64-bit microcontroller environments, the primary governing standards in NuttX are POSIX and ANSI standards. Additional standard APIs from Unix and other common RTOSs (such as VxWorks) are adopted for functionality not available under these standards, or for functionality that is not appropriate for deeply-embedded environments (such as fork()).
For brevity, many parts of the documentation will refer to Apache NuttX as simply NuttX.
Getting Started
First time on NuttX? Read the Getting Started guide! If you don't have a board available, NuttX has its own simulator that you can run on terminal.
Documentation
You can find the current NuttX documentation on the Documentation Page.
Alternatively, you can build the documentation yourself by following the Documentation Build Instructions.
The old NuttX documentation is still available in the Apache wiki.
Supported Boards
NuttX supports a wide variety of platforms. See the full list on the Supported Platforms page.
Contributing
If you wish to contribute to the NuttX project, read the Contributing guidelines for information on Git usage, coding standard, workflow and the NuttX principles.
License
The code in this repository is under either the Apache 2 license, or a license compatible with the Apache 2 license. See the License Page for more information.