Print out OpenCL device version for chosen device in output header

Resolves #4

ocl-stream.cpp

@@ -49,6 +49,7 @@
 #include "common.h"
 
 std::string getDeviceName(const cl::Device& device);
+std::string getDeviceDriver(const cl::Device& device);
 unsigned getDeviceList(std::vector<cl::Device>& devices);
 
 
@@ -163,6 +164,10 @@ int main(int argc, char *argv[])
         std::string name = getDeviceName(device);
         std::cout << "Using OpenCL device " << name << std::endl;
 
+        // Print out OpenCL driver version for this device
+        std::string driver = getDeviceDriver(device);
+        std::cout << "Driver: " << driver << std::endl;
+
         // Check device can do double precision if requested
         if (!useFloat && !device.getInfo<CL_DEVICE_DOUBLE_FP_CONFIG>())
             throw std::runtime_error("Device does not support double precision, please use --float");
@@ -442,6 +447,22 @@ std::string getDeviceName(const cl::Device& device)
     return name;
 }
 
+std::string getDeviceDriver(const cl::Device& device)
+{
+    std::string driver;
+    try
+    {
+        device.getInfo(CL_DRIVER_VERSION, &driver);
+    }
+    catch (cl::Error &e)
+    {
+        die("Getting device driver", e);
+    }
+
+    return driver;
+}
+
+
 void listDevices(void)
 {
     // Get list of devices