10 HPM5301EVKLITE测试USB HID例子通过，REPORT_SIZE该如何理解？

发布于 2024-02-04 01:30:17 浏览：393 订阅该版

1 个回答

aozima 2024-02-04

调网络不抓包，调I2C等时序不上逻辑分析仪，就像电工不用万用表！多用整理的好的文字，比截图更省流量，还能在整理过程中思考。

mumumu 2024-02-04

这家伙很懒，什么也没写！

看到有人提过：HS HID最高是125us一帧，每帧1024字节，最多连续发三帧，也就是
125usX1024字节X3=24MB
这个速度倒是够了，我现在困惑的是REPORT SIZE 测试最大只能1024，也就是与HS的一帧大小一致，
超过这个大小MCU端发送数据主机会等待超时，但是看了厂家硬件层的发送驱动里面：
```
D:\RT-ThreadStudio\workspace\usb_device_generic_hid\libraries\hpm_sdk\components\usb\device\hpm_usb_device.c
```

```c
bool usb_device_edpt_xfer(usb_device_handle_t *handle, uint8_t ep_addr, uint8_t *buffer, uint32_t total_bytes)
{
    uint8_t const epnum = ep_addr & 0x0f;
    uint8_t const dir   = (ep_addr & 0x80) >> 7;
    uint8_t const ep_idx = 2 * epnum + dir;
    uint8_t qtd_num;
    uint8_t i;
    uint32_t xfer_len;
    dcd_qhd_t *p_qhd;
    dcd_qtd_t *p_qtd;
    dcd_qtd_t *first_p_qtd = NULL;
    dcd_qtd_t *prev_p_qtd = NULL;

if (epnum == 0) {
        /* follows UM Setup packet handling using setup lockout mechanism
         * wait until ENDPTSETUPSTAT before priming data/status in response TODO add time out
         */
        while (usb_dcd_get_edpt_setup_status(handle->regs) & HPM_BITSMASK(1, 0)) {
        }
    }

qtd_num = (total_bytes + 0x3fff) / 0x4000;
    if (qtd_num > USB_SOC_DCD_QTD_COUNT_EACH_ENDPOINT) {
        return false;
    }

if (buffer != NULL) {
        buffer = (uint8_t *)core_local_mem_to_sys_address(0, (uint32_t)buffer);
    }
    p_qhd = &handle->dcd_data->qhd[ep_idx];
    i = 0;
    do {
        p_qtd = &handle->dcd_data->qtd[ep_idx * USB_SOC_DCD_QTD_COUNT_EACH_ENDPOINT + i];
        i++;

if (total_bytes > 0x4000) {
            xfer_len = 0x4000;
            total_bytes -= 0x4000;
        } else {
            xfer_len = total_bytes;
            total_bytes = 0;
        }

usb_qtd_init(p_qtd, (void *)buffer, xfer_len);
        if (total_bytes == 0) {
            p_qtd->int_on_complete = true;
        }
        buffer += xfer_len;

if (prev_p_qtd) {
            prev_p_qtd->next = (uint32_t)p_qtd;
        } else {
            first_p_qtd = p_qtd;
        }
        prev_p_qtd = p_qtd;
    } while (total_bytes > 0);

p_qhd->qtd_overlay.next = core_local_mem_to_sys_address(0, (uint32_t) first_p_qtd); /* link qtd to qhd */

if (usb_dcd_edpt_get_type(handle->regs, ep_addr) == usb_xfer_isochronous) {
        p_qhd->iso_mult = 1;
    }
    usb_dcd_edpt_xfer(handle->regs, ep_idx);

return true;
}

```
数据发送会被分割为0x4000大小发送，超过的最多可以发8个这样的数据区，
从底层驱动来说并没有1024的限制，看了windows的驱动也没有说report size限制在1024，
只是看到linux的内核驱动限制在了4096。
所以我想一次发4096的数据，让底层自动触发一个时间片连续三帧的传输。