add controller register interface and support TinyUSB

[hathach]

Whoop, after 2-3 weeks of works, I finally wrap up this PR. This is more difficult than my initial thought. Your repo is going uber low (bit banging) into USB, I learn quite a lot more from your code despite working with USB for quite some time. I could only imagine amount of time and effort you spend on oscilloscope to get this working. Really brilliant work !!

This PR implement #14 and add an register interface for pio-usb port (host/device) similar to native usb controller on rp2040 e.g event interrupt status, ep complete/error/stalled and irq handler. This allow pio-usb "low-level controller part" can be used with tinyusb.

Following is the notable changes:

• Move host and device specific code to pio_usb_host/device.c . This is mostly for maintaining purpose, I think it would be easier to separate code from separated mode. The cons is: this requires common function/variable declaration need to be placed in the an header. Let me know if you prefer to keep it all in one file, I will merge it back.

• Add new internal header pio_usb_ll.h for controller register interface (along with other internal common function of host & device)
• add some extra field for endpoint_t so that I could work as standalone without usb_devices variable. Also allow it to transfer more than max packet size for transfer like control, msc bulk in the future.
• Support for endpoint flow control with NAK if there is no "active" transfer to prevent overrun error. Also support endpoint stalled sent/received
• add PIO_USB_USE_TINYUSB to off-out internal usb host/device stack.
• All the existing API of pio_usb still and should work as it is and require no changes from running examples.

This is no way perfect and not optimized, but I did quite a bit of testing with both host and device. Let me know what you think and would change, I hope we could merge this soon.

Note: For testing with TinyUSB

• check out https://github.com/hathach/tinyusb/tree/pio-host and its submodule lib/Pico-PIO-USB
• compile example host/hid_to_cdc, which is configured to use native usb as cdc device, and pio usb as host to get hid input.
• any input event e.g mouse move, button will be printed to cdc on the native usb.

@tannewt @ladyada

[sekigon-gonnoc]

thank you for your PR, I will review changes within a few days.

[hathach]

thank you for your PR, I will review changes within a few days.

no problems, take your time :)

[sekigon-gonnoc]

I think this PR can be merged after minor revisions.

I confirmed that we can use PIO USB port with TinyUSB stack, and maintainability is improved by separating files. Great work!!

Please refer following review comments.

• I'm palnning move all sources/headers to src/ folder. Because this may affect tinyusb makefiles, could you do that in this PR?
• Could you add description about TinyUSB's hid_to_cdc example to README.md?
• There are also some codes that need to be confirmed.

[sekigon-gonnoc]

Following comments are not necessary to accept this PR, but I want to hear your opinion:

How do you think about PIO_USB_DEFAULT_CONFIG?
Currently, we have to edit pio_usb_configuration.h to edit configuration. To use Pico-PIO-USB as a libraly, it is better to these are configurable without modifying header files (e.g. use #ifndef-#define in header definitions and overwrite them by compile time definitions).
Also, we may have to check PIO sm/instruction memory availability at compile time or initializing.

This is also not related to this PR:

TinyUSB's hid_to_cdc example are not work on Windows because ITF_NUM_TOTAL is wrong. This works by comment out line 84 of usb_descriptors.c
https://github.com/hathach/tinyusb/blob/pio-host/examples/host/hid_to_cdc/src/usb_descriptors.c#L84

[hathach]

I think this PR can be merged after minor revisions.

Great thank you very much 👍 💯

I confirmed that we can use PIO USB port with TinyUSB stack, and maintainability is improved by separating files. Great work!!

Please refer following review comments.

• I'm palnning move all sources/headers to src/ folder. Because this may affect tinyusb makefiles, could you do that in this PR?

Will do this in the next push

• Could you add description about TinyUSB's hid_to_cdc example to README.md?
• There are also some codes that need to be confirmed.

Sure will do, maybe I will add it to examples of this repo as well. Since the tinyusb example is a bit more generic and include too many cross-platform #ifdef that complicate the rp2040 user.

Following comments are not necessary to accept this PR, but I want to hear your opinion:

Ah you are right on the multiple host ports scenario. I will try to fix those and do a full revise as well.

How do you think about PIO_USB_DEFAULT_CONFIG? Currently, we have to edit pio_usb_configuration.h to edit configuration. To use Pico-PIO-USB as a libraly, it is better to these are configurable without modifying header files (e.g. use #ifndef-#define in header definitions and overwrite them by compile time definitions). Also, we may have to check PIO sm/instruction memory availability at compile time or initializing.

Yeah, I am glad you ask, I think about this previously, and intend to make follow up PRs for this very purpose. IMHO, there should be an application config file such as pio_usb_config.h much like tusb_config.h which is located within application sources to set/change value such as DP, DM pin. The pio_usb_configuration.h as you mentioned define default value for those that aren't defined by application. This allow pico-pio-usb to be included as submodule by other project without the need to modify its file (pio_usb_configuration.h) to have desired behavior. To stay compatible with existing app without the configure header, we can use __has_include to check for the header availability.

This is also not related to this PR:

TinyUSB's hid_to_cdc example are not work on Windows because ITF_NUM_TOTAL is wrong. This works by comment out line 84 of usb_descriptors.c https://github.com/hathach/tinyusb/blob/pio-host/examples/host/hid_to_cdc/src/usb_descriptors.c#L84

Ah right, just fixed it, it is copy-paste mistake, Linux is apparently more forgiving on this.

[mnesarco]

Hey Dudes, The work that you are doing here is simply amazing. Thank you so much.

[hathach]

@sekigon-gonnoc 2 new commits doesn't change the code yet, since we are moving codes around (to /src). I think it is best to add an ci to verify build first. I also take the chance to upload the example_binaries (hex + uf2: for usb_device & capture_hid_report), this would help others that want to test out the PR and latest changes without having to do the proper set-up + compile.

https://github.com/hathach/Pico-PIO-USB/actions/runs/2283033358

Will push more update in upcoming days.

[hathach]

• I have followed pr reviews to fix 2 host_send_setup() and remove the un-comment in the configuration.h
• Also add new example/host_hid_to_device_cdc based on the example in tinyusb. It has a simpler tusb_config.h and can be compile right within this repo for reference. Note: pico-sdk/lib/tinyusb need to be switch to tinyusb lastest (but that only need time for pico-sdk to propagate)
• Add ci to build all examples and upload hex/uf2 as downloaded binaries.

TODO: try out multiple host ports, will push/post when there is more update.

PS: Let me know if you have any plan to change or wrap macro in pio_usb_configuratio.h . I could make the changes as well, or we can wait and make the change afterward (follow up PR) if you want to spend time to think more

[hathach]

I still haven't tried out multiple ports, since TinyUSB currently only support max 2 roothub ports (1 for native device, 1 for pio-usb host). Adding more rhport is possible, but required a bit of changing in macro naming etc ... I will try that later on. But the changes of c12e4c5 should be sufficient enough.

For PIO_USB_DEFAULT_CONFIG, I wrap PIO_USB_DP_PIN_DEFAULT with ifdef, since that macro is something user will for sure modify especially the default 0/1 is mostly used for UART TX/RX. The other macros is safely left as it is (until you decide which is best way to handle lib configuration).

Let me know if update look good and/or any request changes you would like to be done.

PS: the examples/host/hid_to_cdc is renamed to examples/dual/host_hid_to_device_cdc in tinyusb

[sekigon-gonnoc]

@hathach I tried multiple ports with example/capture_hid_report, and it works fine. So c12e4c5 is proper.

Do you have any other TODOs in this PR? If not, I will merge this.

[hathach]

Great, thank you for testing out the multiple ports changes. I have no other TODO, please merge it when you have time.

PS: Since the current ci use an tinyusb branch pio-host, I will probably make an pr update when tinyusb's own PR is update as follow up one later on.

[sekigon-gonnoc]

Thank you for your corporation.

[hathach]

it is my pleasure

[hathach]

FYI, I made an twitter video about this PR with mentioned to your github:

• https://twitter.com/tinyusb/status/1526126928989913089