Adding ALL as a parameter value to take the union of all other values as output

I am designing a report in which I have a Parameter color_mode with values Two_Color,Full_color and Balck_White.now I want to add ALL value which when selected will display the whole data of color mode.

In my dataset color_mode is a field  with two_color,full_color and black_white as three distinct values.

Please help me in adding ALL as a value to the parameter & give the desired output.

Leeza Goyal