s390/con3270: reduce f_color and b_color attribute size to 4 bit

As we're only supportign 8 colors, we don't need 8 bits. Reduce the
size to 4 bits to save memory.

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Tested-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

diff --git a/drivers/s390/char/con3270.c b/drivers/s390/char/con3270.c
index 71012c2..698e088 100644 (file)
--- a/drivers/s390/char/con3270.c
+++ b/drivers/s390/char/con3270.c
@@ -45,8 +45,8 @@ static struct raw3270_fn tty3270_fn;
 struct tty3270_attribute {
        unsigned char alternate_charset:1;      /* Graphics charset */
        unsigned char highlight;                /* Blink/reverse/underscore */
-       unsigned char f_color;                  /* Foreground color */
-       unsigned char b_color;                  /* Background color */
+       unsigned char f_color:4;                /* Foreground color */
+       unsigned char b_color:4;                /* Background color */
 };
 
 struct tty3270_cell {
@@ -380,6 +380,18 @@ static char tty3270_graphics_translate(struct tty3270 *tp, char ch)
 static char *tty3270_add_attributes(struct tty3270 *tp, struct tty3270_line *line,
                                    struct tty3270_attribute *attr, char *cp)
 {
+       const unsigned char colors[16] = {
+               [0] = TAC_DEFAULT,
+               [1] = TAC_RED,
+               [2] = TAC_GREEN,
+               [3] = TAC_YELLOW,
+               [4] = TAC_BLUE,
+               [5] = TAC_PINK,
+               [6] = TAC_TURQ,
+               [7] = TAC_WHITE,
+               [9] = TAC_DEFAULT
+       };
+
        struct tty3270_cell *cell;
        int c, i;
 
@@ -392,11 +404,11 @@ static char *tty3270_add_attributes(struct tty3270 *tp, struct tty3270_line *lin
                }
                if (cell->attributes.f_color != attr->f_color) {
                        attr->f_color = cell->attributes.f_color;
-                       cp = tty3270_add_sa(tp, cp, TAT_FGCOLOR, attr->f_color);
+                       cp = tty3270_add_sa(tp, cp, TAT_FGCOLOR, colors[attr->f_color]);
                }
                if (cell->attributes.b_color != attr->b_color) {
                        attr->b_color = cell->attributes.b_color;
-                       cp = tty3270_add_sa(tp, cp, TAT_BGCOLOR, attr->b_color);
+                       cp = tty3270_add_sa(tp, cp, TAT_BGCOLOR, colors[attr->b_color]);
                }
                c = cell->character;
                if (cell->attributes.alternate_charset)
@@ -1391,10 +1403,6 @@ static void tty3270_erase_display(struct tty3270 *tp, int mode)
  */
 static void tty3270_set_attributes(struct tty3270 *tp)
 {
-       static unsigned char colors[] = {
-               TAC_DEFAULT, TAC_RED, TAC_GREEN, TAC_YELLOW, TAC_BLUE,
-               TAC_PINK, TAC_TURQ, TAC_WHITE, 0, TAC_DEFAULT
-       };
        int i, attr;
 
        for (i = 0; i <= tp->esc_npar; i++) {
@@ -1435,7 +1443,7 @@ static void tty3270_set_attributes(struct tty3270 *tp)
                case 36:        /* Cyan */
                case 37:        /* White */
                case 39:        /* Black */
-                       tp->attributes.f_color = colors[attr - 30];
+                       tp->attributes.f_color = attr - 30;
                        break;
                /* Background color. */
                case 40:        /* Black */
@@ -1447,7 +1455,7 @@ static void tty3270_set_attributes(struct tty3270 *tp)
                case 46:        /* Cyan */
                case 47:        /* White */
                case 49:        /* Black */
-                       tp->attributes.b_color = colors[attr - 40];
+                       tp->attributes.b_color = attr - 40;
                        break;
                }
        }