s390/con3270: reduce highlight width to 3 bits

With the previous change this reduces the size of struct tty3270_attribute
from four to two bytes. As we have this struct allocated for each character
cell, this saves quite some 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 698e0881319a83f1ecd49f317dff5e8ec4f74f4a..9ef689c47e0b90ebd2572f9f495da7c6bc88c4d6 100644 (file)
--- a/drivers/s390/char/con3270.c
+++ b/drivers/s390/char/con3270.c
@@ -42,9 +42,13 @@ static int tty3270_max_index;
 static struct tty3270 *condev;
 static struct raw3270_fn tty3270_fn;
 
+#define TTY3270_HIGHLIGHT_BLINK                1
+#define TTY3270_HIGHLIGHT_REVERSE      2
+#define TTY3270_HIGHLIGHT_UNDERSCORE   4
+
 struct tty3270_attribute {
        unsigned char alternate_charset:1;      /* Graphics charset */
-       unsigned char highlight;                /* Blink/reverse/underscore */
+       unsigned char highlight:3;              /* Blink/reverse/underscore */
        unsigned char f_color:4;                /* Foreground color */
        unsigned char b_color:4;                /* Background color */
 };
@@ -301,7 +305,7 @@ static int tty3270_required_length(struct tty3270 *tp, struct tty3270_line *line
        int i, flen = 3;                /* Prefix (TO_SBA). */
 
        flen += line->len;
-       highlight = TAX_RESET;
+       highlight = 0;
        f_color = TAC_RESET;
        b_color = TAC_RESET;
 
@@ -321,7 +325,7 @@ static int tty3270_required_length(struct tty3270 *tp, struct tty3270_line *line
                if (cell->attributes.alternate_charset)
                        flen += 1;      /* TO_GE to switch to graphics extensions */
        }
-       if (highlight != TAX_RESET)
+       if (highlight)
                flen += 3;      /* TO_SA to reset hightlight. */
        if (f_color != TAC_RESET)
                flen += 3;      /* TO_SA to reset color. */
@@ -336,7 +340,7 @@ static int tty3270_required_length(struct tty3270 *tp, struct tty3270_line *line
 static char *tty3270_add_reset_attributes(struct tty3270 *tp, struct tty3270_line *line,
                                          char *cp, struct tty3270_attribute *attr)
 {
-       if (attr->highlight != TAX_RESET)
+       if (attr->highlight)
                cp = tty3270_add_sa(tp, cp, TAT_EXTHI, TAX_RESET);
        if (attr->f_color != TAC_RESET)
                cp = tty3270_add_sa(tp, cp, TAT_FGCOLOR, TAX_RESET);
@@ -392,6 +396,12 @@ static char *tty3270_add_attributes(struct tty3270 *tp, struct tty3270_line *lin
                [9] = TAC_DEFAULT
        };
 
+       const unsigned char highlights[8] = {
+               [TTY3270_HIGHLIGHT_BLINK] = TAX_BLINK,
+               [TTY3270_HIGHLIGHT_REVERSE] = TAX_REVER,
+               [TTY3270_HIGHLIGHT_UNDERSCORE] = TAX_UNDER,
+       };
+
        struct tty3270_cell *cell;
        int c, i;
 
@@ -400,7 +410,7 @@ static char *tty3270_add_attributes(struct tty3270 *tp, struct tty3270_line *lin
        for (i = 0, cell = line->cells; i < line->len; i++, cell++) {
                if (cell->attributes.highlight != attr->highlight) {
                        attr->highlight = cell->attributes.highlight;
-                       cp = tty3270_add_sa(tp, cp, TAT_EXTHI, attr->highlight);
+                       cp = tty3270_add_sa(tp, cp, TAT_EXTHI, highlights[attr->highlight]);
                }
                if (cell->attributes.f_color != attr->f_color) {
                        attr->f_color = cell->attributes.f_color;
@@ -1413,25 +1423,22 @@ static void tty3270_set_attributes(struct tty3270 *tp)
                        break;
                /* Highlight. */
                case 4:         /* Start underlining. */
-                       tp->attributes.highlight = TAX_UNDER;
+                       tp->attributes.highlight = TTY3270_HIGHLIGHT_UNDERSCORE;
                        break;
                case 5:         /* Start blink. */
-                       tp->attributes.highlight = TAX_BLINK;
+                       tp->attributes.highlight = TTY3270_HIGHLIGHT_BLINK;
                        break;
                case 7:         /* Start reverse. */
-                       tp->attributes.highlight = TAX_REVER;
+                       tp->attributes.highlight = TTY3270_HIGHLIGHT_REVERSE;
                        break;
                case 24:        /* End underlining */
-                       if (tp->attributes.highlight == TAX_UNDER)
-                               tp->attributes.highlight = TAX_RESET;
+                       tp->attributes.highlight &= ~TTY3270_HIGHLIGHT_UNDERSCORE;
                        break;
                case 25:        /* End blink. */
-                       if (tp->attributes.highlight == TAX_BLINK)
-                               tp->attributes.highlight = TAX_RESET;
+                       tp->attributes.highlight &= ~TTY3270_HIGHLIGHT_BLINK;
                        break;
                case 27:        /* End reverse. */
-                       if (tp->attributes.highlight == TAX_REVER)
-                               tp->attributes.highlight = TAX_RESET;
+                       tp->attributes.highlight &= ~TTY3270_HIGHLIGHT_REVERSE;
                        break;
                /* Foreground color. */
                case 30:        /* Black */