MIPS: PS2: ROM: Resolve the name for the region in the ROMVER file

'J' indicates Japan, 'E' indicates Europe, 'C' indicates China, 'A' the
USA and 'H' Asia. 'X' indicates a TEST machine, and 'T' either a TOOL
machine or a Namco System 246 archade machine if the ROM type is 'Z'.

Note that 'E' includes Australia and 'A' includes Mexico.

Signed-off-by: Fredrik Noring <noring@nocrew.org>

arch/mips/include/asm/mach-ps2/rom.h

@@ -137,7 +137,8 @@ struct rom_extinfo rom_read_extinfo(const char *name,
  * @date.month: month ROM was created
  * @date.day: day ROM was created
  *
- * The @type name can be resolved with rom_type_name().
+ * The @region and @type names can be resolved with rom_region_name() and
+ * rom_type_name().
  *
  * Note that ``'E'`` includes Australia and ``'A'`` includes Mexico.
  *
@@ -157,6 +158,8 @@ struct rom_ver {
 
 struct rom_ver rom_version(void);
 
+const char *rom_region_name(char region);
+
 const char *rom_type_name(char type);
 
 bool rom_empty_dir(const struct rom_dir dir);

arch/mips/ps2/rom.c

@@ -385,6 +385,26 @@ struct rom_ver rom_version(void)
 }
 EXPORT_SYMBOL_GPL(rom_version);
 
+/**
+ * rom_region_name - name for the ROM region character in the ROMVER file
+ * @region: &rom_ver.region region character.
+ *
+ * Context: any
+ * Return: ROM region name, ``"-"`` if undefined or ``"?"`` if unrecognised
+ */
+const char *rom_region_name(char region)
+{
+	return region == 'J' ? "Japan" :
+	       region == 'E' ? "Europe" : /* Including Australia. */
+	       region == 'C' ? "China" :
+	       region == 'A' ? "USA" :	/* Including Mexico. */
+	       region == 'H' ? "Asia" :	/* Technically same as the USA. */
+	       region == 'T' ? "TOOL" :	/* Namco system if ROM type is 'Z'. */
+	       region == 'X' ? "TEST" :	/* Only the DTL-H10000 model. */
+	       region == '-' ? "-" : "?";
+}
+EXPORT_SYMBOL_GPL(rom_region_name);
+
 /**
  * rom_type_name - name for the ROM type character in the ROMVER file in ROM0
  * @type: &rom_ver.type type character.
@@ -677,8 +697,8 @@ static int __init ps2_rom_init(void)
 	rom1_dir = rom_dir_init("rom1", ROM1_BASE, ROM1_SIZE);
 
 	v = rom_version();
-	pr_info("rom0: Version %04x %c %s %04d-%02d-%02d\n",
-		v.number, v.region, rom_type_name(v.type),
+	pr_info("rom0: Version %04x %s %s %04d-%02d-%02d\n",
+		v.number, rom_region_name(v.region), rom_type_name(v.type),
 		v.date.year, v.date.month, v.date.day);
 
 	return 0;