vt: introduce enum vc_intensity for intensity

Introduce names (en enum) for 0, 1, and 2 constants. We now have
VCI_HALF_BRIGHT, VCI_NORMAL, and VCI_BOLD instead.

Apart from the cleanup,
1) the enum allows for better type checking, and
2) this saves some code. No more fiddling with bits is needed in
   assembly now. (OTOH, the structure is larger.)
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-2-jslaby@suse.czSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/vt/vt.c

@@ -705,8 +705,9 @@ void update_region(struct vc_data *vc, unsigned long start, int count)
 
 /* Structure of attributes is hardware-dependent */
 
-static u8 build_attr(struct vc_data *vc, u8 _color, u8 _intensity, u8 _blink,
-    u8 _underline, u8 _reverse, u8 _italic)
+static u8 build_attr(struct vc_data *vc, u8 _color,
+		enum vc_intensity _intensity, u8 _blink, u8 _underline,
+		u8 _reverse, u8 _italic)
 {
 	if (vc->vc_sw->con_build_attr)
 		return vc->vc_sw->con_build_attr(vc, _color, _intensity,
@@ -734,13 +735,13 @@ static u8 build_attr(struct vc_data *vc, u8 _color, u8 _intensity, u8 _blink,
 		a = (a & 0xF0) | vc->vc_itcolor;
 	else if (_underline)
 		a = (a & 0xf0) | vc->vc_ulcolor;
-	else if (_intensity == 0)
+	else if (_intensity == VCI_HALF_BRIGHT)
 		a = (a & 0xf0) | vc->vc_halfcolor;
 	if (_reverse)
 		a = ((a) & 0x88) | ((((a) >> 4) | ((a) << 4)) & 0x77);
 	if (_blink)
 		a ^= 0x80;
-	if (_intensity == 2)
+	if (_intensity == VCI_BOLD)
 		a ^= 0x08;
 	if (vc->vc_hi_font_mask == 0x100)
 		a <<= 1;
@@ -753,8 +754,9 @@ static void update_attr(struct vc_data *vc)
 	vc->vc_attr = build_attr(vc, vc->state.color, vc->state.intensity,
 	              vc->state.blink, vc->state.underline,
 	              vc->state.reverse ^ vc->vc_decscnm, vc->state.italic);
-	vc->vc_video_erase_char = ' ' | (build_attr(vc, vc->state.color, 1,
-				vc->state.blink, 0, vc->vc_decscnm, 0) << 8);
+	vc->vc_video_erase_char = ' ' | (build_attr(vc, vc->state.color,
+				VCI_NORMAL, vc->state.blink, 0, vc->vc_decscnm,
+				0) << 8);
 }
 
 /* Note: inverting the screen twice should revert to the original state */
@@ -1611,7 +1613,7 @@ static void csi_X(struct vc_data *vc, int vpar) /* erase the following vpar posi
 
 static void default_attr(struct vc_data *vc)
 {
-	vc->state.intensity = 1;
+	vc->state.intensity = VCI_NORMAL;
 	vc->state.italic = 0;
 	vc->state.underline = 0;
 	vc->state.reverse = 0;
@@ -1652,11 +1654,11 @@ static void rgb_foreground(struct vc_data *vc, const struct rgb *c)
 
 	if (hue == 7 && max <= 0x55) {
 		hue = 0;
-		vc->state.intensity = 2;
+		vc->state.intensity = VCI_BOLD;
 	} else if (max > 0xaa)
-		vc->state.intensity = 2;
+		vc->state.intensity = VCI_BOLD;
 	else
-		vc->state.intensity = 1;
+		vc->state.intensity = VCI_NORMAL;
 
 	vc->state.color = (vc->state.color & 0xf0) | hue;
 }
@@ -1715,10 +1717,10 @@ static void csi_m(struct vc_data *vc)
 			default_attr(vc);
 			break;
 		case 1:
-			vc->state.intensity = 2;
+			vc->state.intensity = VCI_BOLD;
 			break;
 		case 2:
-			vc->state.intensity = 0;
+			vc->state.intensity = VCI_HALF_BRIGHT;
 			break;
 		case 3:
 			vc->state.italic = 1;
@@ -1764,7 +1766,7 @@ static void csi_m(struct vc_data *vc)
 			vc->vc_toggle_meta = 1;
 			break;
 		case 22:
-			vc->state.intensity = 1;
+			vc->state.intensity = VCI_NORMAL;
 			break;
 		case 23:
 			vc->state.italic = 0;
@@ -1795,7 +1797,7 @@ static void csi_m(struct vc_data *vc)
 		default:
 			if (vc->vc_par[i] >= 90 && vc->vc_par[i] <= 107) {
 				if (vc->vc_par[i] < 100)
-					vc->state.intensity = 2;
+					vc->state.intensity = VCI_BOLD;
 				vc->vc_par[i] -= 60;
 			}
 			if (vc->vc_par[i] >= 30 && vc->vc_par[i] <= 37)
@@ -1934,7 +1936,7 @@ static void setterm_command(struct vc_data *vc)
 	case 2:	/* set color for half intensity mode */
 		if (vc->vc_can_do_color && vc->vc_par[1] < 16) {
 			vc->vc_halfcolor = color_table[vc->vc_par[1]];
-			if (vc->state.intensity == 0)
+			if (vc->state.intensity == VCI_HALF_BRIGHT)
 				update_attr(vc);
 		}
 		break;

drivers/usb/misc/sisusbvga/sisusb_con.c

@@ -302,14 +302,14 @@ sisusbcon_deinit(struct vc_data *c)
 
 /* interface routine */
 static u8
-sisusbcon_build_attr(struct vc_data *c, u8 color, u8 intensity,
+sisusbcon_build_attr(struct vc_data *c, u8 color, enum vc_intensity intensity,
 			    u8 blink, u8 underline, u8 reverse, u8 unused)
 {
 	u8 attr = color;
 
 	if (underline)
 		attr = (attr & 0xf0) | c->vc_ulcolor;
-	else if (intensity == 0)
+	else if (intensity == VCI_HALF_BRIGHT)
 		attr = (attr & 0xf0) | c->vc_halfcolor;
 
 	if (reverse)
@@ -320,7 +320,7 @@ sisusbcon_build_attr(struct vc_data *c, u8 color, u8 intensity,
 	if (blink)
 		attr ^= 0x80;
 
-	if (intensity == 2)
+	if (intensity == VCI_BOLD)
 		attr ^= 0x08;
 
 	return attr;

drivers/video/console/mdacon.c

@@ -394,7 +394,8 @@ static inline u16 mda_convert_attr(u16 ch)
 		(ch & 0x00ff) | attr;
 }
 
-static u8 mdacon_build_attr(struct vc_data *c, u8 color, u8 intensity, 
+static u8 mdacon_build_attr(struct vc_data *c, u8 color,
+			    enum vc_intensity intensity,
 			    u8 blink, u8 underline, u8 reverse, u8 italic)
 {
 	/* The attribute is just a bit vector:
@@ -405,7 +406,7 @@ static u8 mdacon_build_attr(struct vc_data *c, u8 color, u8 intensity,
 	 *	Bit 7    : blink
 	 */
 
-	return (intensity & 3) |
+	return (intensity & VCI_MASK) |
 		((underline & 1) << 2) |
 		((reverse   & 1) << 3) |
 		(!!italic << 4) |

drivers/video/console/sticon.c

@@ -288,7 +288,8 @@ static unsigned long sticon_getxy(struct vc_data *conp, unsigned long pos,
     return ret;
 }
 
-static u8 sticon_build_attr(struct vc_data *conp, u8 color, u8 intens,
+static u8 sticon_build_attr(struct vc_data *conp, u8 color,
+			    enum vc_intensity intens,
 			    u8 blink, u8 underline, u8 reverse, u8 italic)
 {
     u8 attr = ((color & 0x70) >> 1) | ((color & 7));

drivers/video/console/vgacon.c

@@ -629,7 +629,8 @@ static void vgacon_deinit(struct vc_data *c)
 	con_set_default_unimap(c);
 }
 
-static u8 vgacon_build_attr(struct vc_data *c, u8 color, u8 intensity,
+static u8 vgacon_build_attr(struct vc_data *c, u8 color,
+			    enum vc_intensity intensity,
 			    u8 blink, u8 underline, u8 reverse, u8 italic)
 {
 	u8 attr = color;
@@ -639,7 +640,7 @@ static u8 vgacon_build_attr(struct vc_data *c, u8 color, u8 intensity,
 			attr = (attr & 0xF0) | c->vc_itcolor;
 		else if (underline)
 			attr = (attr & 0xf0) | c->vc_ulcolor;
-		else if (intensity == 0)
+		else if (intensity == VCI_HALF_BRIGHT)
 			attr = (attr & 0xf0) | c->vc_halfcolor;
 	}
 	if (reverse)
@@ -648,14 +649,14 @@ static u8 vgacon_build_attr(struct vc_data *c, u8 color, u8 intensity,
 				       0x77);
 	if (blink)
 		attr ^= 0x80;
-	if (intensity == 2)
+	if (intensity == VCI_BOLD)
 		attr ^= 0x08;
 	if (!vga_can_do_color) {
 		if (italic)
 			attr = (attr & 0xF8) | 0x02;
 		else if (underline)
 			attr = (attr & 0xf8) | 0x01;
-		else if (intensity == 0)
+		else if (intensity == VCI_HALF_BRIGHT)
 			attr = (attr & 0xf0) | 0x08;
 	}
 	return attr;

include/linux/console.h

@@ -35,6 +35,8 @@ enum con_scroll {
 	SM_DOWN,
 };
 
+enum vc_intensity;
+
 /**
  * struct consw - callbacks for consoles
  *
@@ -74,7 +76,8 @@ struct consw {
 	void	(*con_scrolldelta)(struct vc_data *vc, int lines);
 	int	(*con_set_origin)(struct vc_data *vc);
 	void	(*con_save_screen)(struct vc_data *vc);
-	u8	(*con_build_attr)(struct vc_data *vc, u8 color, u8 intensity,
+	u8	(*con_build_attr)(struct vc_data *vc, u8 color,
+			enum vc_intensity intensity,
 			u8 blink, u8 underline, u8 reverse, u8 italic);
 	void	(*con_invert_region)(struct vc_data *vc, u16 *p, int count);
 	u16    *(*con_screen_pos)(struct vc_data *vc, int offset);

include/linux/console_struct.h

@@ -22,6 +22,13 @@ struct uni_screen;
 
 #define NPAR 16
 
+enum vc_intensity {
+	VCI_HALF_BRIGHT,
+	VCI_NORMAL,
+	VCI_BOLD,
+	VCI_MASK = 0x3,
+};
+
 /**
  * struct vc_state -- state of a VC
  * @x: cursor's x-position
@@ -30,7 +37,7 @@ struct uni_screen;
  * @G0_charset: what's G0 slot set to (like GRAF_MAP, LAT1_MAP)
  * @G1_charset: what's G1 slot set to (like GRAF_MAP, LAT1_MAP)
  * @charset: what character set to use (0=G0 or 1=G1)
- * @intensity: 0=half-bright, 1=normal, 2=bold
+ * @intensity: see enum vc_intensity for values
  * @reverse: reversed foreground/background colors
  *
  * These members are defined separately from struct vc_data as we save &
@@ -46,7 +53,7 @@ struct vc_state {
 	unsigned int	charset		: 1;
 
 	/* attribute flags */
-	unsigned int	intensity	: 2;
+	enum vc_intensity intensity;
 	unsigned int	italic		: 1;
 	unsigned int	underline	: 1;
 	unsigned int	blink		: 1;