Add support for forcing a specific driver

This commit adds a new option for forcing the use of a specific driver
indicated via an environment variable.

v2 (Petri):
 - Use an environment variable instead of command line
 - Refactor the loop in __open_device
 - Don't try to load kernel modules

v3 (Petri):
 - Rebase and adjust to the driver loading changes

Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Signed-off-by: Petri Latvala <petri.latvala@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Arkadiusz Hiler <arkadiusz.hiler@intel.com>
Cc: gustavo@padovan.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/lib/drmtest.h b/lib/drmtest.h
index 96ee517e..8743b1bb 100644
--- a/lib/drmtest.h
+++ b/lib/drmtest.h
@@ -52,6 +52,8 @@
  */
 #define DRIVER_ANY 	~(DRIVER_VGEM)
 
+void __set_forced_driver(const char *name);
+
 /**
  * ARRAY_SIZE:
  * @arr: static array