Squashed 'third_party/pico-sdk/lib/tinyusb/' content from commit 868948f67c
Change-Id: I5d33c2566dd597be9d4b1c30d4b3723c5ef4a265
git-subtree-dir: third_party/pico-sdk/lib/tinyusb
git-subtree-split: 868948f67c90fa7c2553cdcd604b52862cf55720
Signed-off-by: Austin Schuh <austin.linux@gmail.com>
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+*********
+Reference
+*********
+
+.. figure:: ../assets/stack.svg
+ :width: 1600px
+ :alt: stackup
+
+ representation of the TinyUSB stack.
+
+Device Stack
+============
+
+Supports multiple device configurations by dynamically changing usb descriptors. Low power functions such like suspend, resume, and remote wakeup. Following device classes are supported:
+
+- Audio Class 2.0 (UAC2)
+- Bluetooth Host Controller Interface (BTH HCI)
+- Communication Class (CDC)
+- Device Firmware Update (DFU): DFU mode (WIP) and Runtinme
+- Human Interface Device (HID): Generic (In & Out), Keyboard, Mouse, Gamepad etc ...
+- Mass Storage Class (MSC): with multiple LUNs
+- Musical Instrument Digital Interface (MIDI)
+- Network with RNDIS, CDC-ECM (work in progress)
+- USB Test and Measurement Class (USBTMC)
+- Vendor-specific class support with generic In & Out endpoints. Can be used with MS OS 2.0 compatible descriptor to load winUSB driver without INF file.
+- `WebUSB <https://github.com/WICG/webusb>`__ with vendor-specific class
+
+If you have special need, `usbd_app_driver_get_cb()` can be used to write your own class driver without modifying the stack. Here is how RPi team add their reset interface [raspberrypi/pico-sdk#197](https://github.com/raspberrypi/pico-sdk/pull/197)
+
+Host Stack
+==========
+
+- Human Interface Device (HID): Keyboard, Mouse, Generic
+- Mass Storage Class (MSC)
+- Hub currently only supports 1 level of hub (due to my laziness)
+
+OS Abstraction layer
+====================
+
+TinyUSB is completely thread-safe by pushing all ISR events into a central queue, then process it later in the non-ISR context task function. It also uses semaphore/mutex to access shared resources such as CDC FIFO. Therefore the stack needs to use some of OS's basic APIs. Following OSes are already supported out of the box.
+
+- **No OS**
+- **FreeRTOS**
+- **Mynewt** Due to the newt package build system, Mynewt examples are better to be on its [own repo](https://github.com/hathach/mynewt-tinyusb-example)
+
+License
+=======
+
+All TinyUSB sources in the `src` folder are licensed under MIT license. However, each file can be individually licensed especially those in `lib` and `hw/mcu` folder. Please make sure you understand all the license term for files you use in your project.
+
+Index
+=====
+
+.. toctree::
+ :maxdepth: 2
+
+ supported
+ getting_started
+ concurrency