uvc_host not support high speed on esp32p4? (IEC-394)

[Dandjinh]

Answers checklist.

• I have read the component documentation ESP-IDF Components and the issue is not addressed there.
• I am using target and esp-idf version as defined in component's idf_component.yml
• I have searched the issue tracker for a similar issue and not found any related issue.

Which component are you using? If you choose Other, provide details in More Information.

host/uvc

ESP-IDF version.

v5.5.1

Development Kit.

ESP32-P4-Module-DEV-KIT

Used Component version.

v2.3.1

More Information.

I am trying to get video streaming from ms2130 which converts HDMI streaming to uvc streaming.
I get yuv2 streambing with only 10fps and mjpeg 30fps but only 1/3 of them could be decoded by jpeg-2d.
Looks like only USB-FS bandwidth works.

project uploads here:esp32p4_uvc.zip

The logs folder contains the log of yuv2 mode, the log of mjpeg mode, the description got by uvc_host_desc_print and the description got by UsbTreeView on Win10.

The result of uvc_host_desc_print cannot show any intf whose MPS is bigger than 1024.

Did I miss something to configure USB in HS mode?

[github-actions]

Hi @Dandjinh! Please be aware that the following suggestions are generated by a bot and haven't been fact-checked by Espressif Systems. We hope that this message will help you until an Espressif Engineer looks at your issue.

---

Based on the information in the provided knowledge sources, the ESP32-P4 hardware and the Espressif USB Host UVC driver do support USB 2.0 High-Speed (HS) mode (480 Mbps):

• ESP32-P4 Hardware Support:
  The ESP32-P4 features a USB 2.0 High-Speed OTG controller with an integrated transceiver, supporting High-Speed (480 Mbps), Full-Speed (12 Mbps), and Low-Speed (1.5 Mbps) operation. In both Host and Device modes, High-Speed is supported, and the hardware is capable of handling large maximum packet sizes (up to 1024 bytes for isochronous and interrupt transfers in HS mode) ESP32-P4 Technical Reference Manual ESP32-P4 Datasheet.

• UVC Host Driver Support:
  The usb_host_uvc component (v2.3.1) explicitly lists ESP32-P4 as a supported target and is designed to work with both Full-Speed and High-Speed USB peripherals. The driver supports isochronous and bulk streaming, dynamic resolution, and large frame buffers in PSRAM usb_host_uvc component documentation.

• Effective Bandwidth:
  For ESP32-P4 in High-Speed mode, the theoretical effective rates for isochronous transfers are much higher than Full-Speed (up to ~57 MB/s for isochronous, with 1024-byte packets and multiple packets per microframe) USB-OTG Peripheral Introduction.

Troubleshooting Your Issue:

• If you are only seeing Full-Speed bandwidth (e.g., limited to 640x480@15fps or similar), it is possible that:

  • The USB device is not being enumerated in High-Speed mode (check the logs for "High-Speed" vs "Full-Speed" device connection).
  • The hardware connection (USB wiring, connectors, or PHY) may not be enabling High-Speed negotiation.
  • The UVC device itself may be defaulting to Full-Speed, or there may be a compatibility issue.
  • The driver or project configuration may not be enabling the correct PHY or mode.

• Maximum Packet Size (MPS):
  In High-Speed mode, the maximum packet size for isochronous endpoints should be up to 1024 bytes. If your descriptors (as printed by uvc_host_desc_print) do not show endpoints with MPS > 1024, this is expected, as 1024 is the HS maximum for isochronous endpoints. If you see only 512 or 600, it may indicate Full-Speed operation.

What to Check:

1. Log Output:
   Confirm in your logs that the device is enumerated as "High-Speed" (not just "Full-Speed"). The UVC driver and hardware will only use HS bandwidth if the device and host negotiate it.

2. Hardware Setup:
   Ensure you are using the correct USB pins for the ESP32-P4 HS PHY (see datasheet: pin49 and pin50 for USB2 OTG PHY DM/DP). Check that your board and cable support HS operation.

3. Project Configuration:
   Make sure the correct USB PHY is selected and initialized in your project. The ESP32-P4 has multiple PHYs and the connection can be changed via EFUSE_USB_PHY_SEL ESP32-P4 USB Function Overview.

4. Driver Version:
   You are using the correct driver version (v2.3.1), which supports ESP32-P4 and HS operation.

Summary:
The ESP32-P4 and the usb_host_uvc driver do support High-Speed USB. If you are not seeing HS bandwidth, it is likely due to hardware setup, device negotiation, or configuration issues rather than a limitation of the driver or chip. Double-check your hardware wiring, ensure the device is HS capable, and verify the logs for HS enumeration.

If you continue to experience issues, please provide the relevant log lines showing device enumeration and speed negotiation, as well as your hardware wiring details.

---

References:

• ESP32-P4 Technical Reference Manual
• usb_host_uvc component documentation
• USB-OTG Peripheral Introduction
• ESP32-P4 USB Function Overview

[tore-espressif]

@Dandjinh Looking at the logs, the camera was correctly enumerated as High Speed. We tested P4 with USB High speed cameras, with maximum MPS (1024) including multiple packet per transaction.

To configure your hardware for better USB receive performance (typical for USB cameras) set (Top) → Component config → USB-OTG → Hardware FIFO size biasing in menconfig to Bias IN. This will allocate more space for USB RX buffer. At the same time make sure that when install USB host lib, set usb_host_config_t.fifo_settings_custom to zero.

The JPEG decoder is capable of decoding FullHD images at 30fps
https://docs.espressif.com/projects/esp-idf/en/stable/esp32p4/api-reference/peripherals/jpeg.html#jpeg-decoder-performance

[Dandjinh]

Hi @tore-espressif , actually the usb device supports MPS 3072.
However, like what I said, MPS more than 1024 cannot be shown under uvc_host_desc_print.

And I do set Bias In while I cannot find usb_host_config_t.fifo_settings_custom with idf-5.5.1.

below log is bl618 chip with same usb device, and it can get uncompress stream under 30fps.

memory: sram[276000] psram[23463dynamic memory init success, ocram heap size = 285 Kbyte, psram heap size = 2296 Kbyte

  ____               __  __      _       _       _     
 |  _ \             / _|/ _|    | |     | |     | |    
 | |_) | ___  _   _| |_| |_ __ _| | ___ | | __ _| |__  
 |  _ < / _ \| | | |  _|  _/ _` | |/ _ \| |/ _` | '_ \ 
 | |_) | (_) | |_| | | | || (_| | | (_) | | (_| | |_) |
 |____/ \___/ \__,_|_| |_| \__,_|_|\___/|_|\__,_|_.__/ 

Build:15:46:44, Oct  6 2025
Copyright (c) 2022 Bouffalolab team
Version of used components:
	Version: component_version_lhal: 811e8c1f
	Version: component_version_sdk: 2.2.0
	Boot2 maybe not exist!
======== flash cfg ========
flash clock      80MHz
flash delay      105,130,3
flash size       0x00800000
jedec id         0x1740C8
mid              0xC8
iomode           0x04
clk delay        0x01
clk invert       0x03
read reg cmd0    0x05
read reg cmd1    0x35
write reg cmd0   0x01
write reg cmd1   0x31
qe write len     0x01
cread support    0x01
cread code       0x20
burst wrap cmd   0x77
===========================
uart  sig1:ffffffff, sig2:0000f32f
clock gen1:9ffffffd, gen2:0fff0c11
board init done
===========================
app begins
Starting usb host task...
led now: 1
[I/USB] EHCI HCIVERSION:0100
[I/USB] EHCI HCSPARAMS:000001
[I/USB] EHCI HCCPARAMS:0006
[I/USB] New high-speed device on Hub 1, Port 1 connected
[I/USB] New device found,idVendor:534d,idProduct:2109,bcdDevice:2100
[I/USB] The device has 5 interfaces
[I/USB] Enumeration success, start loading class driver
[I/USB] Loading video_ctrl class driver
[I/USB] Close video device
[I/USB] ============= Video device information ===================
[I/USB] bcdVDC:0100
[I/USB] Num of altsettings:4
[I/USB] Ingore altsetting 0
[I/USB] Altsetting:1, Ep=83 Attr=05 Mps=800 Interval=01 Mult=00
[I/USB] Altsetting:2, Ep=83 Attr=05 Mps=1024 Interval=01 Mult=01
[I/USB] Altsetting:3, Ep=83 Attr=05 Mps=1024 Interval=01 Mult=02
[I/USB] bNumFormats:2
[I/USB]   FormatIndex:1
[I/USB]   FormatType:mjpeg
[I/USB]   bNumFrames:11
[I/USB]   Resolution:
[I/USB]       FrameIndex:1
[I/USB]       wWidth: 1920, wHeight: 1080
[I/USB]       FrameIndex:2
[I/USB]       wWidth: 1600, wHeight: 1200
[I/USB]       FrameIndex:3
[I/USB]       wWidth: 1360, wHeight: 768
[I/USB]       FrameIndex:4
[I/USB]       wWidth: 1280, wHeight: 1024
[I/USB]       FrameIndex:5
[I/USB]       wWidth: 1280, wHeight: 960
[I/USB]       FrameIndex:6
[I/USB]       wWidth: 1280, wHeight: 720
[I/USB]       FrameIndex:7
[I/USB]       wWidth: 1024, wHeight: 768
[I/USB]       FrameIndex:8
[I/USB]       wWidth: 800, wHeight: 600
[I/USB]       FrameIndex:9
[I/USB]       wWidth: 720, wHeight: 576
[I/USB]       FrameIndex:10
[I/USB]       wWidth: 720, wHeight: 480
[I/USB]       FrameIndex:11
[I/USB]       wWidth: 640, wHeight: 480
[I/USB]   FormatIndex:2
[I/USB]   FormatType:uncompressed
[I/USB]   bNumFrames:11
[I/USB]   Resolution:
[I/USB]       FrameIndex:1
[I/USB]       wWidth: 1920, wHeight: 1080
[I/USB]       FrameIndex:2
[I/USB]       wWidth: 1600, wHeight: 1200
[I/USB]       FrameIndex:3
[I/USB]       wWidth: 1360, wHeight: 768
[I/USB]       FrameIndex:4
[I/USB]       wWidth: 1280, wHeight: 1024
[I/USB]       FrameIndex:5
[I/USB]       wWidth: 1280, wHeight: 960
[I/USB]       FrameIndex:6
[I/USB]       wWidth: 1280, wHeight: 720
[I/USB]       FrameIndex:7
[I/USB]       wWidth: 1024, wHeight: 768
[I/USB]       FrameIndex:8
[I/USB]       wWidth: 800, wHeight: 600
[I/USB]       FrameIndex:9
[I/USB]       wWidth: 720, wHeight: 576
[I/USB]       FrameIndex:10
[I/USB]       wWidth: 720, wHeight: 480
[I/USB]       FrameIndex:11
[I/USB]       wWidth: 640, wHeight: 480
[I/USB] ============= Video device information ===================
[I/USB] Register Video Class:/dev/video0
usbh_video_run_callback:25
[I/USB] Loading video_streaming class driver
[I/USB] Loading audio_ctrl class driver
memory: sram[276644] psram[2346324]
led now: 0
[I/USB] Ep=83 Attr=01 Mps=1024 Interval=01 Mult=00
[I/USB] Open video and select formatidx:2, frameidx:11, altsetting:3
uvc mps :3072
uvc init task delete
memory: sram[276000] psram[2346324]
led now: 1
memory: sram[276000] psram[2346324]
led now: 0
  uvc fps: 30
memory: sram[276000] psram[2346324]
led now: 1
  uvc fps: 30
memory: sram[276000] psram[2346324]
led now: 0
  uvc fps: 30
memory: sram[276000] psram[2346324]
led now: 1
  uvc fps: 30
memory: sram[276000] psram[2346324]
led now: 0
  uvc fps: 30
memory: sram[276000] psram[2346324]
led now: 1
  uvc fps: 30
memory: sram[276000] psram[2346324]
led now: 0

[tore-espressif]

Hello @Dandjinh I believe I understand the problem now. Our UVC driver always tries to select the maximum MPS, but without enabling extra transactions per microframe. This limits the maximum bandwidth and can cause the issues you’re observing.

To provide a bit more context: according to the USB specification, the maximum packet size for an isochronous transfer is 1024 bytes. However, it is possible to have up to two additional transactions per microframe, allowing a total of 3 × 1024 = 3072 bytes to be transferred in a single microframe. The endpoint’s MPS remains 1024 bytes in this case.

This detail is currently not displayed correctly in uvc_host_desc_print; we’ll fix that.

Could you please post a link to the USB camera you are using? I'd like to order it for testing

[Dandjinh]

Hello @tore-espressif It's an HDMI to USB video capture card, has the ms2130 chip inside.
Maybe you could buy it from amazon or ms2130.