leds: core: Add support for composing LED class device names

Add generic support for composing LED class device name. The newly
introduced led_compose_name() function composes device name according
to either <color:function> or <devicename:color:function> pattern,
depending on the configuration of initialization data.

Backward compatibility with in-driver hard-coded LED class device
names is assured thanks to the default_label and devicename properties
of newly introduced struct led_init_data.

In case none of the aforementioned properties was found, then, for OF
nodes, the node name is adopted for LED class device name.

At the occassion of amending the Documentation/leds/leds-class.txt
unify spelling: colour -> color.

Alongside these changes added is a new tool - tools/leds/get_led_device_info.sh.
The tool allows retrieving details of a LED class device's parent device,
which proves that using vendor or product name for devicename part
of LED name doesn't convey any added value since that information had been
already available in sysfs. The script performs also basic validation
of a LED class device name.

Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Baolin Wang <baolin.wang@linaro.org>
Cc: Dan Murphy <dmurphy@ti.com>
Cc: Daniel Mack <daniel@zonque.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Oleh Kravchenko <oleg@kaa.org.ua>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Simon Shields <simon@lineageos.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Pavel Machek <pavel@ucw.cz>

1 files changed, 201 insertions, 0 deletions

diff --git a/tools/leds/get_led_device_info.sh b/tools/leds/get_led_device_info.sh
new file mode 100755
index 000000000000..ccfa442db5fe
--- /dev/null
+++ b/tools/leds/get_led_device_info.sh
@@ -0,0 +1,201 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+
+led_common_defs_path="include/dt-bindings/leds/common.h"
+
+num_args=$#
+if [ $num_args -eq 1 ]; then
+        linux_top=$(dirname `realpath $0` | awk -F/     \
+                        '{                              \
+                                i=1;                    \
+                                while (i <= NF - 2) {   \
+                                        printf $i"/";   \
+                                        i++;            \
+                                };                      \
+                        }')
+	led_defs_path=$linux_top/$led_common_defs_path
+elif [ $num_args -eq 2 ]; then
+        led_defs_path=`realpath $2`
+else
+	echo "Usage: get_led_device_info.sh LED_CDEV_PATH [LED_COMMON_DEFS_PATH]"
+	exit 1
+fi
+
+if [ ! -f $led_defs_path ]; then
+	echo "$led_defs_path doesn't exist"
+	exit 1
+fi
+
+led_cdev_path=`echo $1 | sed s'/\/$//'`
+
+ls "$led_cdev_path/brightness" > /dev/null 2>&1
+if [ $? -ne 0 ]; then
+	echo "Device \"$led_cdev_path\" does not exist."
+	exit 1
+fi
+
+bus=`readlink $led_cdev_path/device/subsystem | sed s'/.*\///'`
+usb_subdev=`readlink $led_cdev_path | grep usb | sed s'/\(.*usb[0-9]*\/[0-9]*-[0-9]*\)\/.*/\1/'`
+ls "$led_cdev_path/device/of_node/compatible" > /dev/null 2>&1
+of_node_missing=$?
+
+if [ "$bus" = "input" ]; then
+	input_node=`readlink $led_cdev_path/device | sed s'/.*\///'`
+	if [ ! -z "$usb_subdev" ]; then
+		bus="usb"
+	fi
+fi
+
+if [ "$bus" = "usb" ]; then
+	usb_interface=`readlink $led_cdev_path | sed s'/.*\(usb[0-9]*\)/\1/' | cut -d\/ -f3`
+	cd $led_cdev_path/../$usb_subdev
+	driver=`readlink $usb_interface/driver | sed s'/.*\///'`
+	if [ -d "$usb_interface/ieee80211" ]; then
+		wifi_phy=`ls -l $usb_interface/ieee80211 | grep phy | awk '{print $9}'`
+	fi
+	idVendor=`cat idVendor`
+	idProduct=`cat idProduct`
+	manufacturer=`cat manufacturer`
+	product=`cat product`
+elif [ "$bus" = "input" ]; then
+	cd $led_cdev_path
+	product=`cat device/name`
+	driver=`cat device/device/driver/description`
+elif [ $of_node_missing -eq 0 ]; then
+	cd $led_cdev_path
+	compatible=`cat device/of_node/compatible`
+	if [ "$compatible" = "gpio-leds" ]; then
+		driver="leds-gpio"
+	elif [ "$compatible" = "pwm-leds" ]; then
+		driver="leds-pwm"
+	else
+		manufacturer=`echo $compatible | awk -F, '{print $1}'`
+		product=`echo $compatible | awk -F, '{print $2}'`
+	fi
+else
+	echo "Unknown device type."
+	exit 1
+fi
+
+printf "\n#####################################\n"
+printf "# LED class device hardware details #\n"
+printf "#####################################\n\n"
+
+printf "bus:\t\t\t$bus\n"
+
+if [ ! -z "$idVendor" ]; then
+	printf "idVendor:\t\t$idVendor\n"
+fi
+
+if [ ! -z "$idProduct" ]; then
+	printf "idProduct:\t\t$idProduct\n"
+fi
+
+if [ ! -z "$manufacturer" ]; then
+	printf "manufacturer:\t\t$manufacturer\n"
+fi
+
+if [ ! -z "$product" ]; then
+	printf "product:\t\t$product\n"
+fi
+
+if [ ! -z "$driver" ]; then
+	printf "driver:\t\t\t$driver\n"
+fi
+
+if [ ! -z "$input_node" ]; then
+	printf "associated input node:\t$input_node\n"
+fi
+
+printf "\n####################################\n"
+printf "# LED class device name validation #\n"
+printf "####################################\n\n"
+
+led_name=`echo $led_cdev_path | sed s'/.*\///'`
+
+num_sections=`echo $led_name | awk -F: '{print NF}'`
+
+if [ $num_sections -eq 1 ]; then
+	printf "\":\" delimiter not detected.\t[ FAILED ]\n"
+	exit 1
+elif [ $num_sections -eq 2 ]; then
+	color=`echo $led_name | cut -d: -f1`
+	function=`echo $led_name | cut -d: -f2`
+elif [ $num_sections -eq 3 ]; then
+	devicename=`echo $led_name | cut -d: -f1`
+	color=`echo $led_name | cut -d: -f2`
+	function=`echo $led_name | cut -d: -f3`
+else
+	printf "Detected %d sections in the LED class device name - should the script be updated?\n" $num_sections
+	exit 1
+fi
+
+S_DEV="devicename"
+S_CLR="color     "
+S_FUN="function  "
+status_tab=20
+
+print_msg_ok()
+{
+	local section_name="$1"
+	local section_val="$2"
+	local msg="$3"
+	printf "$section_name :\t%-${status_tab}.${status_tab}s %s %s\n" "$section_val" "[ OK ]    " "$msg"
+}
+
+print_msg_failed()
+{
+	local section_name="$1"
+	local section_val="$2"
+	local msg="$3"
+	printf "$section_name :\t%-${status_tab}.${status_tab}s %s %s\n" "$section_val" "[ FAILED ]" "$msg"
+}
+
+if [ ! -z "$input_node" ]; then
+	expected_devname=$input_node
+elif [ ! -z "$wifi_phy" ]; then
+	expected_devname=$wifi_phy
+fi
+
+if [ ! -z "$devicename" ]; then
+	if [ ! -z "$expected_devname" ]; then
+		if [ "$devicename" = "$expected_devname" ]; then
+			print_msg_ok "$S_DEV" "$devicename"
+		else
+			print_msg_failed "$S_DEV" "$devicename" "Expected: $expected_devname"
+		fi
+	else
+		if [ "$devicename" = "$manufacturer" ]; then
+			print_msg_failed "$S_DEV" "$devicename" "Redundant: use of vendor name is discouraged"
+		elif [ "$devicename" = "$product" ]; then
+			print_msg_failed "$S_DEV" "$devicename" "Redundant: use of product name is discouraged"
+		else
+			print_msg_failed "$S_DEV" "$devicename" "Unknown devicename - should the script be updated?"
+		fi
+	fi
+elif [ ! -z "$expected_devname" ]; then
+	print_msg_failed "$S_DEV" "blank" "Expected: $expected_devname"
+fi
+
+if [ ! -z "$color" ]; then
+	color_upper=`echo $color | tr [:lower:] [:upper:]`
+	color_id_definition=$(cat $led_defs_path | grep "_$color_upper\s" | awk '{print $2}')
+	if [ ! -z "$color_id_definition" ]; then
+		print_msg_ok "$S_CLR" "$color" "Matching definition: $color_id_definition"
+	else
+		print_msg_failed "$S_CLR" "$color" "Definition not found in $led_defs_path"
+	fi
+
+fi
+
+if [ ! -z "$function" ]; then
+	# strip optional enumerator
+	function=`echo $function | sed s'/\(.*\)-[0-9]*$/\1/'`
+	fun_definition=$(cat $led_defs_path | grep "\"$function\"" | awk '{print $2}')
+	if [ ! -z "$fun_definition" ]; then
+		print_msg_ok "$S_FUN" "$function" "Matching definition: $fun_definition"
+	else
+		print_msg_failed "$S_FUN" "$function" "Definition not found in $led_defs_path"
+	fi
+
+fi