commit 97ddb72359663b5ca9d8e0c22588f0022f729ced
author Alexander Soldatov <a.soldatov@yadro.com> Tue Apr 16 09:10:00 2019 +0300
committer Alexander Amelkin <a.amelkin@yadro.com> Wed Apr 24 21:27:08 2019 +0300
tree a37a44d71d74e67e2d684166c533d78699992996
parent 5b1417bd21d1e9c00b25bb6db700aec442af746d

Add ability to set LED colors in DBus

phosphor-led-sysfs parses sysfs LED node names
in the form of "devicename:colour:function" as
described in

https://github.com/torvalds/linux/blob/master/Documentation/leds/leds-class.txt#L46

and then converts the "colour" part into the proper
value of the DBus 'Color' property using the
xyz.openbmc_project.Led.Physical.Palette interface.

In order for the led nodes to have their Color set,
the corresponding led nodes in devicetree must have
correct 'label' properties, e.g.:

leds {
    compatible = "gpio-leds";

    heartbeat {
        label = "bmc:green:hearbeat";
        gpios = <&gpio ASPEED_GPIO(R, 4) GPIO_ACTIVE_LOW>;
    };
    power_red {
        label = "system:red:power";
        gpios = <&gpio ASPEED_GPIO(N, 1) GPIO_ACTIVE_LOW>;
    };
}

Change-Id: I094f0e434bdd262995752576a3c792ccd5dbb3e2
Signed-off-by: Alexander Soldatov <a.soldatov@yadro.com>
Signed-off-by: Alexander Amelkin <a.amelkin@yadro.com>

controller.cpp

diff --git a/controller.cpp b/controller.cpp
index 82430a7..8b9a22d 100644
--- a/controller.cpp
+++ b/controller.cpp
@@ -21,6 +21,7 @@
 #include "sysfs.hpp"
 
 #include <algorithm>
+#include <boost/algorithm/string.hpp>
 #include <iostream>
 #include <string>
 
@@ -32,6 +33,53 @@
     exit(-1);
 }
 
+struct LedDescr
+{
+    std::string devicename;
+    std::string color;
+    std::string function;
+};
+
+/** @brief parse LED name in sysfs
+ *  Parse sysfs LED name in format "devicename:colour:function"
+ *  or "devicename:colour" or "devicename" and sets corresponding
+ *  fields in LedDescr struct.
+ *
+ *  @param[in] name      - LED name in sysfs
+ *  @param[out] ledDescr - LED description
+ */
+void getLedDescr(const std::string& name, LedDescr& ledDescr)
+{
+    std::vector<std::string> words;
+    boost::split(words, name, boost::is_any_of(":"));
+    try
+    {
+        ledDescr.devicename = words.at(0);
+        ledDescr.color = words.at(1);
+        ledDescr.function = words.at(2);
+    }
+    catch (const std::out_of_range&)
+    {
+        return;
+    }
+}
+
+/** @brief generates LED DBus name from LED description
+ *
+ *  @param[in] name      - LED description
+ *  @return              - DBus LED name
+ */
+std::string getDbusName(const LedDescr& ledDescr)
+{
+    std::vector<std::string> words;
+    words.emplace_back(ledDescr.devicename);
+    if (!ledDescr.function.empty())
+        words.emplace_back(ledDescr.function);
+    if (!ledDescr.color.empty())
+        words.emplace_back(ledDescr.color);
+    return boost::join(words, "_");
+}
+
 int main(int argc, char** argv)
 {
     namespace fs = std::experimental::filesystem;
@@ -53,7 +101,7 @@
 
     // Since this application always gets invoked as part of a udev rule,
     // it is always guaranteed to get /sys/class/leds/one/two
-    // and we can go beyond leds/ to get the actual led name.
+    // and we can go beyond leds/ to get the actual LED name.
     // Refer: systemd/systemd#5072
 
     // On an error, this throws an exception and terminates.
@@ -72,6 +120,11 @@
     // dbus paths and hence need to convert them to underscores.
     std::replace(name.begin(), name.end(), '-', '_');
 
+    // Convert LED name in sysfs into DBus name
+    LedDescr ledDescr;
+    getLedDescr(name, ledDescr);
+    name = getDbusName(ledDescr);
+
     // Unique bus name representing a single LED.
     auto busName = std::string(BUSNAME) + '.' + name;
     auto objPath = std::string(OBJPATH) + '/' + name;
@@ -85,7 +138,7 @@
     // Create the Physical LED objects for directing actions.
     // Need to save this else sdbusplus destructor will wipe this off.
     phosphor::led::SysfsLed sled{fs::path(path)};
-    phosphor::led::Physical led(bus, objPath, sled);
+    phosphor::led::Physical led(bus, objPath, sled, ledDescr.color);
 
     /** @brief Claim the bus */
     bus.request_name(busName.c_str());