How to implement the get report request function in the SDK 15.3.0 hid example? Please provide a function example?

[peter.min]

To realize multi touch in hid, we need to realize get report request to get the maximum number of support points and set report request to set touch mode.
In the SDK 15.3.0 ble app his keyboard routine, we see the P feature report initializer, but we don't see the get report request function.
The get report request function routine in the ble hid example in sdk15.3.0 is provided?

[Kenneth]

Hi,

The HIDS module keeps track of attribute values for each connection object (handle) and uses this tracked state to respond to a GATT client read / write operations. In general you can refer to the hids_init() in ble_app_hids_keyboard example on how to configure the HIDS module (for instance set report map and the number of feature reports supported).

If you want to set a non-zero value for feature reports there are two ways:

1. You can use the following function:
https://gist.github.com/kapi-no/ce902e1aed6aac57eae2c6a3eabf7b58

uint32_t ble_hids_feat_rep_set(ble_hids_t * p_hids,
                               uint8_t      rep_index,
                               uint16_t     len,
                               uint8_t      offset,
                               uint16_t     conn_handle,
                               uint8_t    * p_feat_rep)
{
    VERIFY_PARAM_NOT_NULL(p_hids);
    VERIFY_PARAM_NOT_NULL(p_feat_rep);

    ret_code_t err_code;
    uint8_t  * p_rep_data;
    uint8_t    index;

    if (rep_index >= p_hids->feature_rep_count)
    {
        return NRF_ERROR_INVALID_PARAM;
    }

    err_code = blcm_link_ctx_get(p_hids->p_link_ctx_storage,
                                 conn_handle,
                                 (void *) &p_rep_data);
    VERIFY_SUCCESS(err_code);

    p_rep_data += sizeof(ble_hids_client_context_t) + BOOT_KB_INPUT_REPORT_MAX_SIZE +
                  BOOT_KB_OUTPUT_REPORT_MAX_SIZE + BOOT_MOUSE_INPUT_REPORT_MAX_SIZE;

    for (index = 0; index < p_hids->inp_rep_count; index++)
    {
        p_rep_data += p_hids->p_inp_rep_init_array[index].max_len;
    }

    for (index = 0; index < p_hids->outp_rep_count; index++)
    {
        p_rep_data += p_hids->p_outp_rep_init_array[index].max_len;
    }

    for (index = 0; index < rep_index; index++)
    {
        p_rep_data += p_hids->p_feature_rep_init_array[index].max_len;
    }

    // Copy the requested feature report data
    if (len + offset <= p_hids->p_feature_rep_init_array[rep_index].max_len)
    {
        memcpy(p_rep_data + offset, p_feat_rep, len);
    }
    else
    {
        return NRF_ERROR_INVALID_LENGTH;
    }

    return NRF_SUCCESS;
}

You need to call the ble_hids_feat_rep_set() when you handle the BLE_GAP_EVT_CONNECTED event from Softdevice to set a non-zero value for the feature report(s).

OR

2. Open ble_hids.c and go to on_report_value_read_auth(), then change:
auth_read_params.params.read.update = 0; // Set to 0.

Then calling sd_ble_gatts_value_set() after ble_hids_init() should work, for instance:
err_code= sd_ble_gatts_value_set(m_conn_handle,
m_hids.feature_rep_array[FEATURE_REPORT_INDEX]->char_handles.value_handle,
&gatts_value);

I hope you can use one of the suggestions above.

Best regards,
Kenneth

[peter.min]

I can't visit your sample website. Please send the sample here or my email.

[Kenneth]

I updated my reply with inline code.

Best regards,
Kenneth

[peter.min]

Thank you