[media] gspca_pac7302: extend register documentation

Signed-off-by: Frank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/usb/gspca/pac7302.c

@@ -29,6 +29,15 @@
  * Register page 0:
  *
  * Address	Description
+ * 0x02		Red balance control
+ * 0x03		Green balance control
+ * 0x04 	Blue balance control
+ *		     Valus are inverted (0=max, 255=min).
+ *		     The Windows driver uses a quadratic approach to map
+ *		     the settable values (0-200) on register values:
+ *		     min=0x80, default=0x40, max=0x20
+ * 0x0f-0x20	Colors, saturation and exposure control
+ * 0xa2-0xab	Brightness, contrast and gamma control
  * 0xb6		Sharpness control (bits 0-4)
  *
  * Register page 1: