#define IS_TV_OR_LVDS(c) (c->output_flag & (SDVO_TV_MASK | SDVO_LVDS_MASK))
 
 
-static char *tv_format_names[] = {
+static const char *tv_format_names[] = {
        "NTSC_M"   , "NTSC_J"  , "NTSC_443",
        "PAL_B"    , "PAL_D"   , "PAL_G"   ,
        "PAL_H"    , "PAL_I"   , "PAL_M"   ,
 /** Mapping of command numbers to names, for debug output */
 static const struct _sdvo_cmd_name {
        u8 cmd;
-       char *name;
+       const char *name;
 } sdvo_cmd_names[] = {
     SDVO_CMD_NAME_ENTRY(SDVO_CMD_RESET),
     SDVO_CMD_NAME_ENTRY(SDVO_CMD_GET_DEVICE_CAPS),