Add first

simpleddc/setup.py

@@ -0,0 +1,11 @@
+from setuptools import setup, Extension
+
+module = Extension('simpleddc',
+                   sources=['simpleddc.c', 'simpleddc-python.c'],
+                   libraries=['ddcutil'],
+                   library_dirs=['/usr/lib/aarch64-linux-gnu/libddcutil.so.4'],
+                   include_dirs=['/usr/include'])
+
+setup(name='example',
+      version='1.0',
+      ext_modules=[module])

simpleddc/simple-ddc.h

@@ -0,0 +1,14 @@
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <ddcutil_c_api.h>
+#include <ddcutil_status_codes.h>
+
+DDCA_Display_Handle * open_first_display_by_dlist();
+DDCA_Status switch_input(DDCA_Display_Handle* handle, uint8_t input);
+uint8_t show_any_value(
+        DDCA_Display_Handle     dh,
+        DDCA_Vcp_Value_Type     value_type,
+        DDCA_Vcp_Feature_Code   feature_code);

simpleddc/simpleddc-python.c

@@ -0,0 +1,39 @@
+#include <Python.h>
+#include "simple-ddc.h"
+
+static PyObject* switch_to_input(PyObject* self, PyObject* args) {
+    uint8_t display, input;
+    if (!PyArg_ParseTuple(args, "ii", &display, &input))
+        return NULL;
+
+    DDCA_Display_Handle* handle = open_first_display_by_dlist();
+    switch_input(handle,input);
+    ddca_close_display(handle);
+    Py_RETURN_NONE;
+}
+
+static PyObject* show_input(PyObject* self, PyObject* args) {
+    DDCA_Display_Handle* handle = open_first_display_by_dlist();
+    int result = show_any_value(handle,DDCA_NON_TABLE_VCP_VALUE, 0x60);
+    ddca_close_display(handle);
+    return PyLong_FromLong(result);
+}
+
+static PyMethodDef Methods[] = {
+    {"switch_to_input",  switch_to_input, METH_VARARGS, "Switch to input"},
+    {"show_input", show_input, METH_VARARGS, "Show input"},
+    {NULL, NULL, 0, NULL}        /* Sentinel */
+};
+
+static struct PyModuleDef module = {
+    PyModuleDef_HEAD_INIT,
+    "simpleddc", 
+    NULL, /* module documentation, may be NULL */
+    -1,       /* size of per-interpreter state of the module,
+                 or -1 if the module keeps state in global variables. */
+    Methods
+};
+
+PyMODINIT_FUNC PyInit_simpleddc(void) {
+    return PyModule_Create(&module);
+}

simpleddc/simpleddc.c

@@ -0,0 +1,103 @@
+#include "simple-ddc.h"
+
+#define DDC_ERRMSG(function_name,status_code)    \
+   do {                                               \
+      printf("(%s) %s() returned %d (%s): %s\n",      \
+             __func__, function_name, status_code,    \
+             ddca_rc_name(status_code),               \
+             ddca_rc_desc(status_code));              \
+   } while(0)
+
+DDCA_Display_Handle * open_first_display_by_dlist() {
+   printf("Check for monitors using ddca_get_displays()...\n");
+   DDCA_Display_Handle dh = NULL;
+
+   // Inquire about detected monitors.
+   DDCA_Display_Info_List* dlist = NULL;
+   ddca_get_display_info_list2(
+         false,    // don't include invalid displays
+         &dlist);
+
+   if (dlist->ct == 0) {
+      printf("   No DDC capable displays found\n");
+   }
+   else {
+      DDCA_Display_Info * dinf = &dlist->info[0];
+      DDCA_Display_Ref * dref = dinf->dref;
+      printf("Opening display %s\n", dinf->model_name);
+      printf("Model: %s\n", dinf->model_name);
+      //printf("Model: %s\n", dinf->mmid.model_name);
+      DDCA_Status rc = ddca_open_display2(dref, false, &dh);
+      if (rc != 0) {
+          DDC_ERRMSG("ddca_open_display2", rc);
+      }
+   }
+   ddca_free_display_info_list(dlist);
+   return dh;
+}
+
+uint8_t show_any_value(
+        DDCA_Display_Handle     dh,
+        DDCA_Vcp_Value_Type     value_type,
+        DDCA_Vcp_Feature_Code   feature_code)
+{
+    DDCA_Status ddcrc;
+    DDCA_Any_Vcp_Value * valrec;
+
+    ddcrc = ddca_get_any_vcp_value_using_explicit_type(
+            dh,
+            feature_code,
+            value_type,
+            &valrec);
+    if (ddcrc != 0) {
+        DDC_ERRMSG("ddca_get_any_vcp_value_using_explicit_type", ddcrc);
+        goto bye;
+    }
+
+    if (valrec->value_type == DDCA_NON_TABLE_VCP_VALUE) {
+       /*printf("Non-Table value: mh=0x%02x, ml=0x%02x, sh=0x%02x, ml=0x%02x\n",
+              valrec->val.c_nc.mh,
+              valrec->val.c_nc.ml,
+              valrec->val.c_nc.sh,
+              valrec->val.c_nc.sl);
+       printf("As continuous value (if applicable): max value = %d, cur value = %d\n",
+             valrec->val.c_nc.mh << 8 | valrec->val.c_nc.ml,    // or use macro VALREC_MAX_VAL()
+             valrec->val.c_nc.sh << 8 | valrec->val.c_nc.sl);   // or use macro VALREC_CUR_VAL()*/
+
+        uint8_t ret_value = valrec->val.c_nc.sl;
+        free(valrec);
+        return ret_value;
+    }
+    else {
+       assert(valrec->value_type == DDCA_TABLE_VCP_VALUE);
+       printf("Table value: 0x");
+       for (int ndx=0; ndx<valrec->val.t.bytect; ndx++)
+          printf("%02x", valrec->val.t.bytes[ndx]);
+       puts("");
+    }
+
+ bye:
+   if (valrec != NULL)
+      free(valrec);
+   return 0;
+}
+
+DDCA_Status switch_input(DDCA_Display_Handle* handle, uint8_t input) {
+    bool saved_enable_verify = ddca_enable_verify(true);
+
+    DDCA_Status ddcrc = ddca_set_non_table_vcp_value(handle,0x60, 0, input);
+
+    if (ddcrc == DDCRC_VERIFY) {
+        printf("Value verification failed.  Current value is now:\n");
+        show_any_value(handle, DDCA_NON_TABLE_VCP_VALUE, 0x60);
+     }
+     else if (ddcrc != 0) {
+        DDC_ERRMSG("ddca_set_non_table_vcp_value", ddcrc);
+     }
+     else {
+        printf("Setting new value succeeded.\n");
+     }
+
+     ddca_enable_verify(saved_enable_verify);
+     return ddcrc;
+}