[PATCH] drm: Make drm.debug parameter description more helpful

[Ezequiel Garcia]

Let's be user-friendly and print an actually helpful parameter
description.

Signed-off-by: Ezequiel Garcia <ezequiel at vanguardiasur.com.ar>
---
 drivers/gpu/drm/drm_drv.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index 167c8d3d4a31..49b658069b51 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -37,15 +37,24 @@
 #include "drm_legacy.h"
 #include "drm_internal.h"
 
-unsigned int drm_debug = 0;	/* bitmask of DRM_UT_x */
+/*
+ * drm_debug: Enable debug output.
+ * Bitmask of DRM_UT_x. See include/drm/drmP.h for details.
+ */
+unsigned int drm_debug = 0;
 EXPORT_SYMBOL(drm_debug);
 
 MODULE_AUTHOR(CORE_AUTHOR);
 MODULE_DESCRIPTION(CORE_DESC);
 MODULE_LICENSE("GPL and additional rights");
-MODULE_PARM_DESC(debug, "Enable debug output");
+MODULE_PARM_DESC(debug, "Enables debug output, where each bit enables a debug category.\n"
+"Bit 0 (0x1) will enable CORE messages (drm core code)\n"
+"Bit 1 (0x2) will enable DRIVER messages (drm controller code)\n"
+"Bit 2 (0x4) will enable KMS messages (modesetting code)\n"
+"Bit 3 (0x8) will enable PRMIE messages (prime code)\n");
 module_param_named(debug, drm_debug, int, 0600);
 
+
 static DEFINE_SPINLOCK(drm_minor_lock);
 static struct idr drm_minors_idr;
 
-- 
2.7.0