openwrt/target/linux/bcm27xx/patches-4.19/950-0251-overlays-Update-README-with-removal-of-lirc-rpi.patch

From f2c24ce7e03d059fa9f674d8ebf6286e8f0c38b6 Mon Sep 17 00:00:00 2001
From: Phil Elwell <phil@raspberrypi.org>
Date: Wed, 5 Dec 2018 11:56:40 +0000
Subject: [PATCH] overlays: Update README with removal of lirc-rpi

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
---
 arch/arm/boot/dts/overlays/README | 57 ++++++++++++-------------------
 1 file changed, 21 insertions(+), 36 deletions(-)

--- a/arch/arm/boot/dts/overlays/README
+++ b/arch/arm/boot/dts/overlays/README
@@ -56,23 +56,29 @@ have its contents deleted (or commented
 Using Overlays
 ==============
 
-Overlays are loaded using the "dtoverlay" directive. As an example, consider
-the popular lirc-rpi module, the Linux Infrared Remote Control driver. In the
-pre-DT world this would be loaded from /etc/modules, with an explicit
-"modprobe lirc-rpi" command, or programmatically by lircd. With DT enabled,
-this becomes a line in config.txt:
-
-    dtoverlay=lirc-rpi
-
-This causes the file /boot/overlays/lirc-rpi.dtbo to be loaded. By
-default it will use GPIOs 17 (out) and 18 (in), but this can be modified using
-DT parameters:
-
-    dtoverlay=lirc-rpi,gpio_out_pin=17,gpio_in_pin=13
-
-Parameters always have default values, although in some cases (e.g. "w1-gpio")
-it is necessary to provided multiple overlays in order to get the desired
-behaviour. See the list of overlays below for a description of the parameters
+Overlays are loaded using the "dtoverlay" config.txt setting. As an example,
+consider I2C Real Time Clock drivers. In the pre-DT world these would be loaded
+by writing a magic string comprising a device identifier and an I2C address to
+a special file in /sys/class/i2c-adapter, having first loaded the driver for
+the I2C interface and the RTC device - something like this:
+
+    modprobe i2c-bcm2835
+    modprobe rtc-ds1307
+    echo ds1307 0x68 > /sys/class/i2c-adapter/i2c-1/new_device
+
+With DT enabled, this becomes a line in config.txt:
+
+    dtoverlay=i2c-rtc,ds1307
+
+This causes the file /boot/overlays/i2c-rtc.dtbo to be loaded and a "node"
+describing the DS1307 I2C device to be added to the Device Tree for the Pi. By
+default it usees address 0x68, but this can be modified with an additional DT
+parameter:
+
+    dtoverlay=i2c-rtc,ds1307,addr=0x68
+
+Parameters usually have default values, although certain parameters are
+mandatory. See the list of overlays below for a description of the parameters
 and their defaults.
 
 The Overlay and Parameter Reference
@@ -1135,29 +1141,8 @@ Params: <None>
 
 
 Name:   lirc-rpi
-Info:   Configures lirc-rpi (Linux Infrared Remote Control for Raspberry Pi)
-        Consult the module documentation for more details.
-Load:   dtoverlay=lirc-rpi,<param>=<val>
-Params: gpio_out_pin            GPIO for output (default "17")
-
-        gpio_in_pin             GPIO for input (default "18")
-
-        gpio_in_pull            Pull up/down/off on the input pin
-                                (default "down")
-
-        sense                   Override the IR receive auto-detection logic:
-                                 "0" = force active-high
-                                 "1" = force active-low
-                                 "-1" = use auto-detection
-                                (default "-1")
-
-        softcarrier             Turn the software carrier "on" or "off"
-                                (default "on")
-
-        invert                  "on" = invert the output pin (default "off")
-
-        debug                   "on" = enable additional debug messages
-                                (default "off")
+Info:   This overlay has been deprecated and removed - see gpio-ir
+Load:   <Deprecated>
 
 
 Name:   ltc294x