我的树莓派4B的OS版本Raspbian GNU/Linux 10 (buster)，获取的命令为 cat /etc/os-release

1. 修改/boot/config.txt
   sudo nano /boot/config.txt. 把下列行的注释去掉（去掉井号）,gpio-ir负责接收，gpio-ir-tx负责发送。我只需要接收，所以gpio-ir-tx仍然保持注释

dtoverlay=gpio-ir,gpio_pin=17
#dtoverlay=gpio-ir-tx,gpio_pin=18

2. 安装lirc

sudo apt-get update
sudo apt-get install lirc

3. 编辑Edit Lirc_options.conf
   编辑/etc/lirc/lirc_options.conf， 修改下面的两行

driver = default
device = /dev/lirc0

驱动使用 default，自带的里面是devinput。device使用 /dev/lirc0，对应于红外接收设备

4. 放置lircd的配置文件
   把对应于自己遥控器的lircd文件放到 /etc/lirc/lircd.conf。 如果没有lircd的配置文件，可能需要自己录制一个，可以参考irrecord命令
5. 重启。重启后，在/dev下应该有lirc0设备。如果启用了gpio-ir-tx，还会有lirc1设备。
6. 输入irw，这时按遥控器按钮应该有输出。

pi@raspberrypi:~/.config $ irw
000000000000000c 00 KEY_NUMERIC_2 ./lircd.conf
000000000000000c 00 KEY_NUMERIC_2 ./lircd.conf
000000000000000b 00 KEY_NUMERIC_1 ./lircd.conf
000000000000000a 00 KEY_NUMERIC_0 ./lircd.conf
0000000000000014 00 BTN_0 ./lircd.conf
0000000000000015 00 BTN_1 ./lircd.con

7. python集成
   如果要用python调用，sudo apt-get install python-pylirc. 不过这个包只有在python2下安装了。我还没研究怎么装到python3下面。

写了一段代码，可以用遥控器控制Turtle模块画图。这里的init用到的/etc/lirc/zzpconf是lircrc的config，参考LIRC配置文件格式

import pylirc
import time
import turtle

pen = turtle.Pen()
pen.speed(200)

pylirc.init("pylirc", "/etc/lirc/zzpconf", 1)
while True:
    x = pylirc.nextcode()
    print(x)
    if x is None:
        continue
    if x[0] == 'KEY_NUMERIC_2':
        pen.setheading(90)
        pen.forward(20)
    elif x[0] == 'KEY_NUMERIC_8':
        pen.setheading(-90)
        pen.forward(20)
    elif x[0] == 'KEY_NUMERIC_4':
        pen.setheading(180)
        pen.forward(20)
    elif x[0] == 'KEY_NUMERIC_6':
        pen.setheading(0)
        pen.forward(20)
    elif x[0] == 'KEY_NUMERIC_5':
        pen.clear()
    elif x[0] == 'KEY_VOLUMEUP':
        pen.penup()
    elif x[0] == 'KEY_VOLUMEDOWN':
        pen.pendown()
    
    

我的lircrc配置文件供参考

begin
  remote = *
  button = KEY_CHANNELDOWN
  prog = pylirc
  config = KEY_CHANNELDOWN
end

begin
  remote = *
  button = KEY_CHANNEL
  prog = pylirc
  config = KEY_CHANNEL
end

begin
  remote = *
  button = KEY_CHANNELUP
  prog = pylirc
  config = KEY_CHANNELUP
end

begin
  remote = *
  button = KEY_PREVIOUS
  prog = pylirc
  config = KEY_PREVIOUS
end

begin
  remote = *
  button = KEY_NEXT
  prog = pylirc
  config = KEY_NEXT
end

begin
  remote = *
  button = KEY_PLAYPAUSE
  prog = pylirc
  config = KEY_PLAYPAUSE
end

begin
  remote = *
  button = KEY_VOLUMEDOWN
  prog = pylirc
  config = KEY_VOLUMEDOWN
end

begin
  remote = *
  button = KEY_VOLUMEUP
  prog = pylirc
  config = KEY_VOLUMEUP
end

begin
  remote = *
  button = KEY_EQUAL
  prog = pylirc
  config = KEY_EQUAL
end

begin
  remote = *
  button = KEY_NUMERIC_0
  prog = pylirc
  config = KEY_NUMERIC_0
end

begin
  remote = *
  button = KEY_NUMERIC_1
  prog = pylirc
  config = KEY_NUMERIC_1
end

begin
  remote = *
  button = KEY_NUMERIC_2
  prog = pylirc
  config = KEY_NUMERIC_2
end

begin
  remote = *
  button = KEY_NUMERIC_3
  prog = pylirc
  config = KEY_NUMERIC_3
end

begin
  remote = *
  button = KEY_NUMERIC_4
  prog = pylirc
  config = KEY_NUMERIC_4
end

begin
  remote = *
  button = KEY_NUMERIC_5
  prog = pylirc
  config = KEY_NUMERIC_5
end

begin
  remote = *
  button = KEY_NUMERIC_6
  prog = pylirc
  config = KEY_NUMERIC_6
end

begin
  remote = *
  button = KEY_NUMERIC_7
  prog = pylirc
  config = KEY_NUMERIC_7
end

begin
  remote = *
  button = KEY_NUMERIC_8
  prog = pylirc
  config = KEY_NUMERIC_8
end

begin
  remote = *
  button = KEY_NUMERIC_9
  prog = pylirc
  config = KEY_NUMERIC_9
end

begin
  remote = *
  button = BTN_0
  prog = pylirc
  config = BTN_0
 end

begin
  remote = *
  button = BTN_1
  prog = pylirc
  config = BTN_1:
end

参考:

Easy Setup IR Remote Control Using LIRC for the Raspberry PI (RPi) - Updated Oct 2021 [Part 1] : 7 Steps - Instructables
LIRC配置文件格式
LIRCD文档
python-lirc · PyPI
Infra-Red Remotes - LibreELEC.wiki