variable max

[warlordattack]

Hello, i have upload/download from my internet box

1/
i want to set max as : upload + download

type: custom:dual-gauge-card
title: fbx
min: 0
max: sensor.my_fbx
outer:
entity: sensor.my_fbx
attribute: up
label: up
inner:
entity: sensor.my_fbx
attribute: down
label: down

sensors.yaml :

• platform: template
  sensors:
  my_fbx:
  unique_id: my_fbx
  friendly_name: "Freebox u/d max"
  unit_of_measurement: "mbps"
  icon_template: 'mdi:network'
  value_template: >
  {% set u = states('sensor.freebox_upload_speed') | int %}
  {% set d = states('sensor.freebox_download_speed') | int %}
  {{ (u + d) }}
  attribute_templates:
  up: "{{ states('sensor.freebox_upload_speed') | int }}"
  down: "{{ states('sensor.freebox_download_speed') | int }}"
  updown: "{{ (states('sensor.freebox_upload_speed') | int) + (states('sensor.freebox_download_speed') | int) | int }}"

My sensor works well,
but max do not take sensor.my_fbx value wich is equal to up+down
example : up=5 down=7 sensor.my_fbx=12 : max should be 12

2/
inside sensor.my_fbx i have 3 attributes : up, down, updown
could i define max as an attribute ?

instead of :
max: sensor.my_fbx

i would like :
max:
entity: sensor.my_fbx
attribute: updown

This syntax seem not work ?

help please :)

[gerar19]

This is perfect, but it doesn't work...