viafb: improve misc register handling

viafb: improve misc register handling

This patch improves the misc register handling by adding a modify
function for this to via_io.h and moving expanded definitions of the
relevant ports there. The code was changed to use those to improve
readability.

Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>

drivers/video/via/hw.c

@@ -1394,8 +1394,6 @@ u32 viafb_get_clk_value(int clk)
 /* Set VCLK*/
 void viafb_set_vclock(u32 CLK, int set_iga)
 {
-	unsigned char RegTemp;
-
 	/* H.W. Reset : ON */
 	viafb_write_reg_mask(CR17, VIACR, 0x00, BIT7);
 
@@ -1468,8 +1466,7 @@ void viafb_set_vclock(u32 CLK, int set_iga)
 	}
 
 	/* Fire! */
-	RegTemp = inb(VIARMisc);
-	outb(RegTemp | (BIT2 + BIT3), VIAWMisc);
+	via_write_misc_reg_mask(0x0C, 0x0C); /* select external clock */
 }
 
 void viafb_load_crtc_timing(struct display_timing device_timing,
@@ -1713,6 +1710,7 @@ void viafb_fill_crtc_timing(struct crt_mode_table *crt_table,
 	int index = 0;
 	int h_addr, v_addr;
 	u32 pll_D_N;
+	u8 polarity = 0;
 
 	for (i = 0; i < video_mode->mode_array; i++) {
 		index = i;
@@ -1741,20 +1739,11 @@ void viafb_fill_crtc_timing(struct crt_mode_table *crt_table,
 	v_addr = crt_reg.ver_addr;
 
 	/* update polarity for CRT timing */
-	if (crt_table[index].h_sync_polarity == NEGATIVE) {
-		if (crt_table[index].v_sync_polarity == NEGATIVE)
-			outb((inb(VIARMisc) & (~(BIT6 + BIT7))) |
-			     (BIT6 + BIT7), VIAWMisc);
-		else
-			outb((inb(VIARMisc) & (~(BIT6 + BIT7))) | (BIT6),
-			     VIAWMisc);
-	} else {
-		if (crt_table[index].v_sync_polarity == NEGATIVE)
-			outb((inb(VIARMisc) & (~(BIT6 + BIT7))) | (BIT7),
-			     VIAWMisc);
-		else
-			outb((inb(VIARMisc) & (~(BIT6 + BIT7))), VIAWMisc);
-	}
+	if (crt_table[index].h_sync_polarity == NEGATIVE)
+		polarity |= BIT6;
+	if (crt_table[index].v_sync_polarity == NEGATIVE)
+		polarity |= BIT7;
+	via_write_misc_reg_mask(polarity, BIT6 | BIT7);
 
 	if (set_iga == IGA1) {
 		viafb_unlock_crt();
@@ -2123,7 +2112,7 @@ int viafb_setmode(struct VideoModeTable *vmode_tbl, int video_bpp,
 
 	/* Fill VPIT Parameters */
 	/* Write Misc Register */
-	outb(VPIT.Misc, VIAWMisc);
+	outb(VPIT.Misc, VIA_MISC_REG_WRITE);
 
 	/* Write Sequencer */
 	for (i = 1; i <= StdSR; i++)

drivers/video/via/share.h

@@ -45,8 +45,6 @@
 
 /* standard VGA IO port
 */
-#define VIARMisc    0x3CC
-#define VIAWMisc    0x3C2
 #define VIAStatus   0x3DA
 #define VIACR       0x3D4
 #define VIASR       0x3C4

drivers/video/via/via_io.h

@@ -29,6 +29,9 @@
 #include <linux/types.h>
 #include <linux/io.h>
 
+#define VIA_MISC_REG_READ	0x03CC
+#define VIA_MISC_REG_WRITE	0x03C2
+
 /*
  * Indexed port operations.  Note that these are all multi-op
  * functions; every invocation will be racy if you're not holding
@@ -55,4 +58,10 @@ static inline void via_write_reg_mask(u16 port, u8 index, u8 data, u8 mask)
 	outb((data & mask) | (old & ~mask), port + 1);
 }
 
+static inline void via_write_misc_reg_mask(u8 data, u8 mask)
+{
+	u8 old = inb(VIA_MISC_REG_READ);
+	outb((data & mask) | (old & ~mask), VIA_MISC_REG_WRITE);
+}
+
 #endif /* __VIA_IO_H__ */