Add libgpiod feature to mts-io-sysfs

1 files changed, 53 insertions, 0 deletions

diff --git a/src/Device/Device.cpp b/src/Device/Device.cpp
index 1a2aca5..c99e252 100644
--- a/src/Device/Device.cpp
+++ b/src/Device/Device.cpp
@@ -15,6 +15,7 @@
  *
  ***********************************************************************/
 
+#include <gpiod.h>
 #include "Device.h"
 
 const std::vector<std::string> Device::apIdentifiers = {
@@ -494,8 +495,34 @@ void Device::printUsage(std::string program) {
     exitHandler(0);
 }
 
+/* If the name starts in upper case, assume
+ * the name is a GPIO line name from gpio-hog
+ * in device tree.  If it starts in lower case
+ * assume the name is an attribute of the mts-io
+ * driver. GPIOs can only be zero
+ * or one, never a text string.
+ */
 void Device::show(std::string name) {
     std::string fileData;
+    char chipname[64];
+    unsigned int offset;
+    int retval;
+
+    if(isupper(name[0])) {
+        retval = gpiod_ctxless_find_line(name.c_str(), chipname,
+                                    sizeof chipname,&offset);
+        if(retval != -1)
+            retval = gpiod_ctxless_get_value(chipname, offset,
+                                            false, CMDNAME);
+        if(retval != -1) {
+            if(retval == 0)
+                printf("0\n");
+            else
+                printf("1\n");
+            exitHandler(0);
+        }
+    }
+
     int32_t code = MTS::System::readFile(SYSFS_PLATFORM + name, fileData);
     if (code == 0) {
         printf("%s", fileData.c_str());
@@ -519,12 +546,38 @@ void Device::showTrigger(std::string name) {
     exitHandler(99);
 }
 
+// Prefer gpiod if name starts with upper case and is value 0 or 1
 void Device::store(std::string name, std::string value) {
+    int intvalue = -1;
+    int prefergpiod = 0;
+    char chipname[64];
+    unsigned int offset;
+    int retval;
+
     if (!isRoot) {
         printError("Must be root to store to %s", name.c_str());
         exitHandler(99);
     }
     printDebug("Setting %s to %s", name.c_str(), value.c_str());
+    if(isupper(name[0])) {
+        if (value.compare("0") == 0)
+            intvalue = 0;
+        if (value.compare("1") == 0)
+            intvalue = 1;
+        if ((intvalue != -1))
+            prefergpiod = 1;
+    }
+
+    if(prefergpiod) {
+        retval = gpiod_ctxless_find_line(name.c_str(), chipname,
+                                        sizeof chipname,&offset);
+        if(retval != -1)
+            retval = gpiod_ctxless_set_value(chipname, offset, intvalue,
+                                    false, CMDNAME, NULL, NULL);
+        if(retval != -1)
+            return;
+    }
+
     std::ofstream fileToWrite(SYSFS_PLATFORM + name);
     if (fileToWrite.is_open()) {
         fileToWrite << value;