Improve readme and help

2 files changed, 11 insertions, 0 deletions

diff --git a/README b/README
index f034049..34c784c 100644
--- a/README
+++ b/README
@@ -18,3 +18,8 @@ Operations:
   m, max			get maximum brightness of the device.
   s, set VALUE			set brightness of the device.
 
+Valid values:
+  specific value		Example: 500
+  percentage value		Example: 50%
+  specific delta		Example: 50-
+  percentage delta		Example: 50%-
diff --git a/brightnessctl.c b/brightnessctl.c
index 4f47cd1..3810267 100644
--- a/brightnessctl.c
+++ b/brightnessctl.c
@@ -502,6 +502,12 @@ Operations:\n\
   g, get\t\t\tget current brightness of the device.\n\
   m, max\t\t\tget maximum brightness of the device.\n\
   s, set VALUE\t\t\tset brightness of the device.\n\
+\n\
+Valid values:\n\
+  specific value\t\tExample: 500\n\
+  percentage value\t\tExample: 50%%\n\
+  specific delta\t\tExample: 50-\n\
+  percentage delta\t\tExample: 50%%-\n\
 \n");
 }