Enable dithering for ns2501 DVO

Submitted by Thomas Richter on April 14, 2015, 10:02 p.m.

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Message ID 552D8E61.7000106@math.tu-berlin.de
State New
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Commit Message

Thomas Richter April 14, 2015, 10:02 p.m.
Hi Daniel, hi Ville,

please find a patch attached for the NatSemi 2501 DVO found in the 
Fujitsu S6010 (and others). This patch
includes proper definitions for some registers of the (undocumented) 
scaler of the DVO chip, and
also enables dithering by default on all modes. This improves image 
quality significantly in the 32bit
modes as it avoids stair cases due to quantization.

It should hopefully also open a door for future automatic mode computations.

What is still unclear is the proper configuration of the PLL of the 
chip. It seems to consist of a numerator/
denominator pair in registers 1b,1c,1d, though its precise configuration 
is still a mystery.

Note also that the DVO configuration found in the previous kernel driver 
enabled the DVO bypass for
the 1024x768 mode, and hence could not run enable dithering there 
either. The BIOS left no useful
defaults for the scaler in this mode, so I had to obtain this by some 
computation and some try and error.

Unfortunately, it is still unclear which registers define the output 
(panel) configuration as I have only
a single panel available for testing. A laptop with a larger panel using 
the 2501 would certainly be helpful
to understand the rest of the registers.

Greetings,
     Thomas
Signed-off-by: Thomas Richter <thor@math.tu-berlin.de>
---

Patch hide | download patch | download mbox

--- dvo_ns2501.c-org	2015-04-14 15:34:34.000000000 +0200
+++ dvo_ns2501.c	2015-04-14 23:46:16.000000000 +0200
@@ -60,6 +60,130 @@ 
 
 #define NS2501_REGC 0x0c
 
+/*
+ * The following registers are not part of the official datasheet
+ * and are the result of reverse engineering.
+ */
+
+/*
+ * Register c0 controls how the DVO synchronizes with
+ * its input.
+ */
+#define NS2501_REGC0 0xc0
+#define NS2501_C0_ENABLE (1<<0)	/* enable the DVO sync in general */
+#define NS2501_C0_HSYNC (1<<1)	/* synchronize horizontal with input */
+#define NS2501_C0_VSYNC (1<<2)	/* synchronize vertical with input */
+#define NS2501_C0_RESET (1<<7)	/* reset the synchronization flip/flops */
+
+/*
+ * Register 41 is somehow related to the sync register and sync
+ * configuration. It should be 0x32 whenever regC0 is 0x05 (hsync off)
+ * and 0x00 otherwise.
+ */
+#define NS2501_REG41 0x41
+
+/*
+ * this register controls the dithering of the DVO
+ * One bit enables it, the other define the dithering depth.
+ * The higher the value, the lower the dithering depth.
+ */
+#define NS2501_F9_REG 0xf9
+#define NS2501_F9_ENABLE (1<<0)		/* if set, dithering is enabled */
+#define NS2501_F9_DITHER_MASK (0x7f<<1)	/* controls the dither depth */
+#define NS2501_F9_DITHER_SHIFT 1	/* shifts the dither mask */
+
+/*
+ * PLL configuration register. This is a pair of registers,
+ * one single byte register at 1B, and a pair at 1C,1D.
+ * These registers are counters/dividers.
+ */
+#define NS2501_REG1B 0x1b /* one byte PLL control register */
+#define NS2501_REG1C 0x1c /* low-part of the second register */
+#define NS2501_REG1D 0x1d /* high-part of the second register */
+
+/*
+ * Scaler control registers. Horizontal at b8,b9,
+ * vertical at 10,11. The scale factor is computed as
+ * 2^16/control-value. The low-byte comes first.
+ */
+#define NS2501_REG10 0x10 /* low-byte vertical scaler */
+#define NS2501_REG11 0x11 /* high-byte vertical scaler */
+#define NS2501_REGB8 0xb8 /* low-byte horizontal scaler */
+#define NS2501_REGB9 0xb9 /* high-byte horizontal scaler */
+
+/*
+ * Display window definition. This consists of four registers
+ * per dimension. One register pair defines the start of the
+ * display, one the end.
+ * As far as I understand, this defines the window within which
+ * the scaler samples the input.
+ */
+#define NS2501_REGC1 0xc1 /* low-byte horizontal display start */
+#define NS2501_REGC2 0xc2 /* high-byte horizontal display start */
+#define NS2501_REGC3 0xc3 /* low-byte horizontal display stop */
+#define NS2501_REGC4 0xc4 /* high-byte horizontal display stop */
+#define NS2501_REGC5 0xc5 /* low-byte vertical display start */
+#define NS2501_REGC6 0xc6 /* high-byte vertical display start */
+#define NS2501_REGC7 0xc7 /* low-byte vertical display stop */
+#define NS2501_REGC8 0xc8 /* high-byte vertical display stop */
+
+/*
+ * The following register pair seems to define the start of
+ * the vertical sync. If automatic syncing is enabled, and the
+ * register value defines a sync pulse that is later than the
+ * incoming sync, then the register value is ignored and the
+ * external hsync triggers the synchronization.
+ */
+#define NS2501_REG80 0x80 /* low-byte vsync-start */
+#define NS2501_REG81 0x81 /* high-byte vsync-start */
+
+/*
+ * The following register pair seems to define the total number
+ * of lines created at the output side of the scaler.
+ * This is again a low-high register pair.
+ */
+#define NS2501_REG82 0x82 /* output display height, low byte */
+#define NS2501_REG83 0x83 /* output display height, high byte */
+
+/*
+ * The following registers define the end of the front-porch
+ * in horizontal and vertical position and hence allow to shift
+ * the image left/right or up/down.
+ */
+#define NS2501_REG98 0x98 /* horizontal start of display + 256, low */
+#define NS2501_REG99 0x99 /* horizontal start of display + 256, high */
+#define NS2501_REG8E 0x8e /* vertical start of the display, low byte */
+#define NS2501_REG8F 0x8f /* vertical start of the display, high byte */
+
+/*
+ * The following register pair control the function of the
+ * backlight and the DVO output. To enable the corresponding
+ * function, the corresponding bit must be set in both registers.
+ */
+#define NS2501_REG34 0x34 /* DVO enable functions, first register */
+#define NS2501_REG35 0x35 /* DVO enable functions, second register */
+#define NS2501_34_ENABLE_OUTPUT (1<<0) /* enable DVO output */
+#define NS2501_34_ENABLE_BACKLIGHT (1<<1) /* enable backlight */
+
+/*
+ * Registers 9C and 9D define the vertical output offset
+ * of the visible region.
+ */
+#define NS2501_REG9C 0x9c
+#define NS2501_REG9D 0x9d
+
+/*
+ * The register 9F defines the dithering. This requires the
+ * scaler to be ON. Bit 0 enables dithering, the remaining
+ * bits control the depth of the dither. The higher the value,
+ * the LOWER the dithering amplitude. A good value seems to be
+ * 15 (total register value).
+ */
+#define NS2501_REGF9 0xf9
+#define NS2501_F9_ENABLE_DITHER (1<<0) /* enable dithering */
+#define NS2501_F9_DITHER_MASK (0x7f<<1) /* dither masking */
+#define NS2501_F9_DITHER_SHIFT 1	/* upshift of the dither mask */
+
 enum {
 	MODE_640x480,
 	MODE_800x600,
@@ -72,274 +196,178 @@ 
 };
 
 /*
- * Magic values based on what the BIOS on
- * Fujitsu-Siemens Lifebook S6010 programs (1024x768 panel).
+ * The following structure keeps the complete configuration of
+ * the DVO, given a specific output configuration.
+ * This is pretty much guess-work from reverse-engineering, so
+ * read all this with a grain of salt.
  */
-static const struct ns2501_reg regs_1024x768[][86] = {
+struct ns2501_configuration {
+	uint8_t sync;		/* configuration of the C0 register */
+	uint8_t conf;		/* configuration register 8 */
+	uint8_t syncb;		/* configuration register 41 */
+	uint8_t	dither;		/* configuration of the dithering */
+	uint8_t pll_a;		/* PLL configuration, register A, 1B */
+	uint16_t pll_b;		/* PLL configuration, register B, 1C/1D */
+	uint16_t hstart;	/* horizontal start, registers C1/C2 */
+	uint16_t hstop;		/* horizontal total, registers C3/C4 */
+	uint16_t vstart;	/* vertical start, registers C5/C6 */
+	uint16_t vstop;		/* vertical total, registers C7/C8 */
+	uint16_t vsync;         /* manual vertical sync start, 80/81 */
+	uint16_t vtotal;        /* number of lines generated, 82/83 */
+	uint16_t hpos;		/* horizontal position + 256, 98/99  */
+	uint16_t vpos;		/* vertical position, 8e/8f */
+	uint16_t voffs;		/* vertical output offset, 9c/9d */
+	uint16_t hscale;	/* horizontal scaling factor, b8/b9 */
+	uint16_t vscale;	/* vertical scaling factor, 10/11 */
+};
+
+/*
+ * DVO configuration values, partially based on what the BIOS
+ * of the Fujitsu Lifebook S6010 writes into registers,
+ * partially found by manual tweaking. These configurations assume
+ * a 1024x768 panel.
+ */
+static const struct ns2501_configuration ns2501_modes[] = {
 	[MODE_640x480] = {
-		[0] = { .offset = 0x0a, .value = 0x81, },
-		[1] = { .offset = 0x18, .value = 0x07, },
-		[2] = { .offset = 0x19, .value = 0x00, },
-		[3] = { .offset = 0x1a, .value = 0x00, },
-		[4] = { .offset = 0x1b, .value = 0x11, },
-		[5] = { .offset = 0x1c, .value = 0x54, },
-		[6] = { .offset = 0x1d, .value = 0x03, },
-		[7] = { .offset = 0x1e, .value = 0x02, },
-		[8] = { .offset = 0xf3, .value = 0x90, },
-		[9] = { .offset = 0xf9, .value = 0x00, },
-		[10] = { .offset = 0xc1, .value = 0x90, },
-		[11] = { .offset = 0xc2, .value = 0x00, },
-		[12] = { .offset = 0xc3, .value = 0x0f, },
-		[13] = { .offset = 0xc4, .value = 0x03, },
-		[14] = { .offset = 0xc5, .value = 0x16, },
-		[15] = { .offset = 0xc6, .value = 0x00, },
-		[16] = { .offset = 0xc7, .value = 0x02, },
-		[17] = { .offset = 0xc8, .value = 0x02, },
-		[18] = { .offset = 0xf4, .value = 0x00, },
-		[19] = { .offset = 0x80, .value = 0xff, },
-		[20] = { .offset = 0x81, .value = 0x07, },
-		[21] = { .offset = 0x82, .value = 0x3d, },
-		[22] = { .offset = 0x83, .value = 0x05, },
-		[23] = { .offset = 0x94, .value = 0x00, },
-		[24] = { .offset = 0x95, .value = 0x00, },
-		[25] = { .offset = 0x96, .value = 0x05, },
-		[26] = { .offset = 0x97, .value = 0x00, },
-		[27] = { .offset = 0x9a, .value = 0x88, },
-		[28] = { .offset = 0x9b, .value = 0x00, },
-		[29] = { .offset = 0x98, .value = 0x00, },
-		[30] = { .offset = 0x99, .value = 0x00, },
-		[31] = { .offset = 0xf7, .value = 0x88, },
-		[32] = { .offset = 0xf8, .value = 0x0a, },
-		[33] = { .offset = 0x9c, .value = 0x24, },
-		[34] = { .offset = 0x9d, .value = 0x00, },
-		[35] = { .offset = 0x9e, .value = 0x25, },
-		[36] = { .offset = 0x9f, .value = 0x03, },
-		[37] = { .offset = 0xa0, .value = 0x28, },
-		[38] = { .offset = 0xa1, .value = 0x01, },
-		[39] = { .offset = 0xa2, .value = 0x28, },
-		[40] = { .offset = 0xa3, .value = 0x05, },
-		[41] = { .offset = 0xb6, .value = 0x09, },
-		[42] = { .offset = 0xb8, .value = 0x00, },
-		[43] = { .offset = 0xb9, .value = 0xa0, },
-		[44] = { .offset = 0xba, .value = 0x00, },
-		[45] = { .offset = 0xbb, .value = 0x20, },
-		[46] = { .offset = 0x10, .value = 0x00, },
-		[47] = { .offset = 0x11, .value = 0xa0, },
-		[48] = { .offset = 0x12, .value = 0x02, },
-		[49] = { .offset = 0x20, .value = 0x00, },
-		[50] = { .offset = 0x22, .value = 0x00, },
-		[51] = { .offset = 0x23, .value = 0x00, },
-		[52] = { .offset = 0x24, .value = 0x00, },
-		[53] = { .offset = 0x25, .value = 0x00, },
-		[54] = { .offset = 0x8c, .value = 0x10, },
-		[55] = { .offset = 0x8d, .value = 0x02, },
-		[56] = { .offset = 0x8e, .value = 0x10, },
-		[57] = { .offset = 0x8f, .value = 0x00, },
-		[58] = { .offset = 0x90, .value = 0xff, },
-		[59] = { .offset = 0x91, .value = 0x07, },
-		[60] = { .offset = 0x92, .value = 0xa0, },
-		[61] = { .offset = 0x93, .value = 0x02, },
-		[62] = { .offset = 0xa5, .value = 0x00, },
-		[63] = { .offset = 0xa6, .value = 0x00, },
-		[64] = { .offset = 0xa7, .value = 0x00, },
-		[65] = { .offset = 0xa8, .value = 0x00, },
-		[66] = { .offset = 0xa9, .value = 0x04, },
-		[67] = { .offset = 0xaa, .value = 0x70, },
-		[68] = { .offset = 0xab, .value = 0x4f, },
-		[69] = { .offset = 0xac, .value = 0x00, },
-		[70] = { .offset = 0xa4, .value = 0x84, },
-		[71] = { .offset = 0x7e, .value = 0x18, },
-		[72] = { .offset = 0x84, .value = 0x00, },
-		[73] = { .offset = 0x85, .value = 0x00, },
-		[74] = { .offset = 0x86, .value = 0x00, },
-		[75] = { .offset = 0x87, .value = 0x00, },
-		[76] = { .offset = 0x88, .value = 0x00, },
-		[77] = { .offset = 0x89, .value = 0x00, },
-		[78] = { .offset = 0x8a, .value = 0x00, },
-		[79] = { .offset = 0x8b, .value = 0x00, },
-		[80] = { .offset = 0x26, .value = 0x00, },
-		[81] = { .offset = 0x27, .value = 0x00, },
-		[82] = { .offset = 0xad, .value = 0x00, },
-		[83] = { .offset = 0x08, .value = 0x30, }, /* 0x31 */
-		[84] = { .offset = 0x41, .value = 0x00, },
-		[85] = { .offset = 0xc0, .value = 0x05, },
+		.sync	= NS2501_C0_ENABLE | NS2501_C0_VSYNC,
+		.conf	= NS2501_8_VEN | NS2501_8_HEN | NS2501_8_PD,
+		.syncb	= 0x32,
+		.dither	= 15,
+		.pll_a	= 0x11,
+		.pll_b	= 0x354,
+		.hstart	= 0x90,
+		.hstop	= 0x30f,
+		.vstart	= 0x16,
+		.vstop	= 0x202,
+		.vsync	= 0x7ff, /* actually, ignored with this config */
+		.vtotal	= 0x53d,
+		.hpos	= 0x0,
+		.vpos	= 0x10,
+		.voffs	= 0x24,
+		.hscale	= 0xa000,
+		.vscale	= 0xa000
 	},
 	[MODE_800x600] = {
-		[0] = { .offset = 0x0a, .value = 0x81, },
-		[1] = { .offset = 0x18, .value = 0x07, },
-		[2] = { .offset = 0x19, .value = 0x00, },
-		[3] = { .offset = 0x1a, .value = 0x00, },
-		[4] = { .offset = 0x1b, .value = 0x19, },
-		[5] = { .offset = 0x1c, .value = 0x64, },
-		[6] = { .offset = 0x1d, .value = 0x02, },
-		[7] = { .offset = 0x1e, .value = 0x02, },
-		[8] = { .offset = 0xf3, .value = 0x90, },
-		[9] = { .offset = 0xf9, .value = 0x00, },
-		[10] = { .offset = 0xc1, .value = 0xd7, },
-		[11] = { .offset = 0xc2, .value = 0x00, },
-		[12] = { .offset = 0xc3, .value = 0xf8, },
-		[13] = { .offset = 0xc4, .value = 0x03, },
-		[14] = { .offset = 0xc5, .value = 0x1a, },
-		[15] = { .offset = 0xc6, .value = 0x00, },
-		[16] = { .offset = 0xc7, .value = 0x73, },
-		[17] = { .offset = 0xc8, .value = 0x02, },
-		[18] = { .offset = 0xf4, .value = 0x00, },
-		[19] = { .offset = 0x80, .value = 0x27, },
-		[20] = { .offset = 0x81, .value = 0x03, },
-		[21] = { .offset = 0x82, .value = 0x41, },
-		[22] = { .offset = 0x83, .value = 0x05, },
-		[23] = { .offset = 0x94, .value = 0x00, },
-		[24] = { .offset = 0x95, .value = 0x00, },
-		[25] = { .offset = 0x96, .value = 0x05, },
-		[26] = { .offset = 0x97, .value = 0x00, },
-		[27] = { .offset = 0x9a, .value = 0x88, },
-		[28] = { .offset = 0x9b, .value = 0x00, },
-		[29] = { .offset = 0x98, .value = 0x00, },
-		[30] = { .offset = 0x99, .value = 0x00, },
-		[31] = { .offset = 0xf7, .value = 0x88, },
-		[32] = { .offset = 0xf8, .value = 0x06, },
-		[33] = { .offset = 0x9c, .value = 0x23, },
-		[34] = { .offset = 0x9d, .value = 0x00, },
-		[35] = { .offset = 0x9e, .value = 0x25, },
-		[36] = { .offset = 0x9f, .value = 0x03, },
-		[37] = { .offset = 0xa0, .value = 0x28, },
-		[38] = { .offset = 0xa1, .value = 0x01, },
-		[39] = { .offset = 0xa2, .value = 0x28, },
-		[40] = { .offset = 0xa3, .value = 0x05, },
-		[41] = { .offset = 0xb6, .value = 0x09, },
-		[42] = { .offset = 0xb8, .value = 0x30, },
-		[43] = { .offset = 0xb9, .value = 0xc8, },
-		[44] = { .offset = 0xba, .value = 0x00, },
-		[45] = { .offset = 0xbb, .value = 0x20, },
-		[46] = { .offset = 0x10, .value = 0x20, },
-		[47] = { .offset = 0x11, .value = 0xc8, },
-		[48] = { .offset = 0x12, .value = 0x02, },
-		[49] = { .offset = 0x20, .value = 0x00, },
-		[50] = { .offset = 0x22, .value = 0x00, },
-		[51] = { .offset = 0x23, .value = 0x00, },
-		[52] = { .offset = 0x24, .value = 0x00, },
-		[53] = { .offset = 0x25, .value = 0x00, },
-		[54] = { .offset = 0x8c, .value = 0x10, },
-		[55] = { .offset = 0x8d, .value = 0x02, },
-		[56] = { .offset = 0x8e, .value = 0x04, },
-		[57] = { .offset = 0x8f, .value = 0x00, },
-		[58] = { .offset = 0x90, .value = 0xff, },
-		[59] = { .offset = 0x91, .value = 0x07, },
-		[60] = { .offset = 0x92, .value = 0xa0, },
-		[61] = { .offset = 0x93, .value = 0x02, },
-		[62] = { .offset = 0xa5, .value = 0x00, },
-		[63] = { .offset = 0xa6, .value = 0x00, },
-		[64] = { .offset = 0xa7, .value = 0x00, },
-		[65] = { .offset = 0xa8, .value = 0x00, },
-		[66] = { .offset = 0xa9, .value = 0x83, },
-		[67] = { .offset = 0xaa, .value = 0x40, },
-		[68] = { .offset = 0xab, .value = 0x32, },
-		[69] = { .offset = 0xac, .value = 0x00, },
-		[70] = { .offset = 0xa4, .value = 0x80, },
-		[71] = { .offset = 0x7e, .value = 0x18, },
-		[72] = { .offset = 0x84, .value = 0x00, },
-		[73] = { .offset = 0x85, .value = 0x00, },
-		[74] = { .offset = 0x86, .value = 0x00, },
-		[75] = { .offset = 0x87, .value = 0x00, },
-		[76] = { .offset = 0x88, .value = 0x00, },
-		[77] = { .offset = 0x89, .value = 0x00, },
-		[78] = { .offset = 0x8a, .value = 0x00, },
-		[79] = { .offset = 0x8b, .value = 0x00, },
-		[80] = { .offset = 0x26, .value = 0x00, },
-		[81] = { .offset = 0x27, .value = 0x00, },
-		[82] = { .offset = 0xad, .value = 0x00, },
-		[83] = { .offset = 0x08, .value = 0x30, }, /* 0x31 */
-		[84] = { .offset = 0x41, .value = 0x00, },
-		[85] = { .offset = 0xc0, .value = 0x07, },
+		.sync	= NS2501_C0_ENABLE |
+			  NS2501_C0_HSYNC | NS2501_C0_VSYNC,
+		.conf   = NS2501_8_VEN | NS2501_8_HEN | NS2501_8_PD,
+		.syncb	= 0x00,
+		.dither	= 15,
+		.pll_a	= 0x19,
+		.pll_b	= 0x264,
+		.hstart	= 0xd7,
+		.hstop	= 0x3f8,
+		.vstart	= 0x1a,
+		.vstop	= 0x273,
+		.vsync	= 0x327,
+		.vtotal	= 0x53d,
+		.hpos	= 0x0,
+		.vpos	= 0x4,
+		.voffs	= 0x23,
+		.hscale	= 0xc830,
+		.vscale	= 0xc820
 	},
 	[MODE_1024x768] = {
-		[0] = { .offset = 0x0a, .value = 0x81, },
-		[1] = { .offset = 0x18, .value = 0x07, },
-		[2] = { .offset = 0x19, .value = 0x00, },
-		[3] = { .offset = 0x1a, .value = 0x00, },
-		[4] = { .offset = 0x1b, .value = 0x11, },
-		[5] = { .offset = 0x1c, .value = 0x54, },
-		[6] = { .offset = 0x1d, .value = 0x03, },
-		[7] = { .offset = 0x1e, .value = 0x02, },
-		[8] = { .offset = 0xf3, .value = 0x90, },
-		[9] = { .offset = 0xf9, .value = 0x00, },
-		[10] = { .offset = 0xc1, .value = 0x90, },
-		[11] = { .offset = 0xc2, .value = 0x00, },
-		[12] = { .offset = 0xc3, .value = 0x0f, },
-		[13] = { .offset = 0xc4, .value = 0x03, },
-		[14] = { .offset = 0xc5, .value = 0x16, },
-		[15] = { .offset = 0xc6, .value = 0x00, },
-		[16] = { .offset = 0xc7, .value = 0x02, },
-		[17] = { .offset = 0xc8, .value = 0x02, },
-		[18] = { .offset = 0xf4, .value = 0x00, },
-		[19] = { .offset = 0x80, .value = 0xff, },
-		[20] = { .offset = 0x81, .value = 0x07, },
-		[21] = { .offset = 0x82, .value = 0x3d, },
-		[22] = { .offset = 0x83, .value = 0x05, },
-		[23] = { .offset = 0x94, .value = 0x00, },
-		[24] = { .offset = 0x95, .value = 0x00, },
-		[25] = { .offset = 0x96, .value = 0x05, },
-		[26] = { .offset = 0x97, .value = 0x00, },
-		[27] = { .offset = 0x9a, .value = 0x88, },
-		[28] = { .offset = 0x9b, .value = 0x00, },
-		[29] = { .offset = 0x98, .value = 0x00, },
-		[30] = { .offset = 0x99, .value = 0x00, },
-		[31] = { .offset = 0xf7, .value = 0x88, },
-		[32] = { .offset = 0xf8, .value = 0x0a, },
-		[33] = { .offset = 0x9c, .value = 0x24, },
-		[34] = { .offset = 0x9d, .value = 0x00, },
-		[35] = { .offset = 0x9e, .value = 0x25, },
-		[36] = { .offset = 0x9f, .value = 0x03, },
-		[37] = { .offset = 0xa0, .value = 0x28, },
-		[38] = { .offset = 0xa1, .value = 0x01, },
-		[39] = { .offset = 0xa2, .value = 0x28, },
-		[40] = { .offset = 0xa3, .value = 0x05, },
-		[41] = { .offset = 0xb6, .value = 0x09, },
-		[42] = { .offset = 0xb8, .value = 0x00, },
-		[43] = { .offset = 0xb9, .value = 0xa0, },
-		[44] = { .offset = 0xba, .value = 0x00, },
-		[45] = { .offset = 0xbb, .value = 0x20, },
-		[46] = { .offset = 0x10, .value = 0x00, },
-		[47] = { .offset = 0x11, .value = 0xa0, },
-		[48] = { .offset = 0x12, .value = 0x02, },
-		[49] = { .offset = 0x20, .value = 0x00, },
-		[50] = { .offset = 0x22, .value = 0x00, },
-		[51] = { .offset = 0x23, .value = 0x00, },
-		[52] = { .offset = 0x24, .value = 0x00, },
-		[53] = { .offset = 0x25, .value = 0x00, },
-		[54] = { .offset = 0x8c, .value = 0x10, },
-		[55] = { .offset = 0x8d, .value = 0x02, },
-		[56] = { .offset = 0x8e, .value = 0x10, },
-		[57] = { .offset = 0x8f, .value = 0x00, },
-		[58] = { .offset = 0x90, .value = 0xff, },
-		[59] = { .offset = 0x91, .value = 0x07, },
-		[60] = { .offset = 0x92, .value = 0xa0, },
-		[61] = { .offset = 0x93, .value = 0x02, },
-		[62] = { .offset = 0xa5, .value = 0x00, },
-		[63] = { .offset = 0xa6, .value = 0x00, },
-		[64] = { .offset = 0xa7, .value = 0x00, },
-		[65] = { .offset = 0xa8, .value = 0x00, },
-		[66] = { .offset = 0xa9, .value = 0x04, },
-		[67] = { .offset = 0xaa, .value = 0x70, },
-		[68] = { .offset = 0xab, .value = 0x4f, },
-		[69] = { .offset = 0xac, .value = 0x00, },
-		[70] = { .offset = 0xa4, .value = 0x84, },
-		[71] = { .offset = 0x7e, .value = 0x18, },
-		[72] = { .offset = 0x84, .value = 0x00, },
-		[73] = { .offset = 0x85, .value = 0x00, },
-		[74] = { .offset = 0x86, .value = 0x00, },
-		[75] = { .offset = 0x87, .value = 0x00, },
-		[76] = { .offset = 0x88, .value = 0x00, },
-		[77] = { .offset = 0x89, .value = 0x00, },
-		[78] = { .offset = 0x8a, .value = 0x00, },
-		[79] = { .offset = 0x8b, .value = 0x00, },
-		[80] = { .offset = 0x26, .value = 0x00, },
-		[81] = { .offset = 0x27, .value = 0x00, },
-		[82] = { .offset = 0xad, .value = 0x00, },
-		[83] = { .offset = 0x08, .value = 0x34, }, /* 0x35 */
-		[84] = { .offset = 0x41, .value = 0x00, },
-		[85] = { .offset = 0xc0, .value = 0x01, },
-	},
+		.sync	= NS2501_C0_ENABLE | NS2501_C0_VSYNC,
+		.conf   = NS2501_8_VEN | NS2501_8_HEN | NS2501_8_PD,
+		.syncb	= 0x32,
+		.dither	= 15,
+		.pll_a	= 0x0b,
+		.pll_b	= 0x546,
+		.hstart	= 0x114,
+		.hstop	= 0x513,
+		.vstart	= 0x0f,
+		.vstop	= 0x420,
+		.vsync	= 0x7ff,
+		.vtotal	= 0x53d,
+		.hpos	= 0x0,
+		.vpos	= 0x07,
+		.voffs	= 0x1b,
+		.hscale	= 0xffff,
+		.vscale	= 0xffff
+	}
+};
+
+/*
+ * Other configuration values left by the BIOS of the
+ * Fujitsu S6010 in the DVO control registers. Their
+ * value does not depend on the BIOS and their meaning
+ * is unknown.
+ */
+
+static const struct ns2501_reg mode_agnostic_values[] = {
+	/* 08 is mode specific */
+	[0] = { .offset = 0x0a, .value = 0x81, },
+	/* 10,11 are part of the mode specific configuration */
+	[1] = { .offset = 0x12, .value = 0x02, },
+	[2] = { .offset = 0x18, .value = 0x07, },
+	[3] = { .offset = 0x19, .value = 0x00, },
+	[4] = { .offset = 0x1a, .value = 0x00, }, /* PLL?, ignored */
+	/* 1b,1c,1d are part of the mode specific configuration */
+	[5] = { .offset = 0x1e, .value = 0x02, },
+	[6] = { .offset = 0x1f, .value = 0x40, },
+	[7] = { .offset = 0x20, .value = 0x00, },
+	[8] = { .offset = 0x21, .value = 0x00, },
+	[9] = { .offset = 0x22, .value = 0x00, },
+	[10] = { .offset = 0x23, .value = 0x00, },
+	[11] = { .offset = 0x24, .value = 0x00, },
+	[12] = { .offset = 0x25, .value = 0x00, },
+	[13] = { .offset = 0x26, .value = 0x00, },
+	[14] = { .offset = 0x27, .value = 0x00, },
+	[15] = { .offset = 0x7e, .value = 0x18, },
+	/* 80-84 are part of the mode-specific configuration */
+	[16] = { .offset = 0x84, .value = 0x00, },
+	[17] = { .offset = 0x85, .value = 0x00, },
+	[18] = { .offset = 0x86, .value = 0x00, },
+	[19] = { .offset = 0x87, .value = 0x00, },
+	[20] = { .offset = 0x88, .value = 0x00, },
+	[21] = { .offset = 0x89, .value = 0x00, },
+	[22] = { .offset = 0x8a, .value = 0x00, },
+	[23] = { .offset = 0x8b, .value = 0x00, },
+	[24] = { .offset = 0x8c, .value = 0x10, },
+	[25] = { .offset = 0x8d, .value = 0x02, },
+	/* 8e,8f are part of the mode-specific configuration */
+	[26] = { .offset = 0x90, .value = 0xff, },
+	[27] = { .offset = 0x91, .value = 0x07, },
+	[28] = { .offset = 0x92, .value = 0xa0, },
+	[29] = { .offset = 0x93, .value = 0x02, },
+	[30] = { .offset = 0x94, .value = 0x00, },
+	[31] = { .offset = 0x95, .value = 0x00, },
+	[32] = { .offset = 0x96, .value = 0x05, },
+	[33] = { .offset = 0x97, .value = 0x00, },
+	/* 98,99 are part of the mode-specific configuration */
+	[34] = { .offset = 0x9a, .value = 0x88, },
+	[35] = { .offset = 0x9b, .value = 0x00, },
+	/* 9c,9d are part of the mode-specific configuration */
+	[38] = { .offset = 0x9e, .value = 0x25, },
+	[39] = { .offset = 0x9f, .value = 0x03, },
+	[40] = { .offset = 0xa0, .value = 0x28, },
+	[41] = { .offset = 0xa1, .value = 0x01, },
+	[42] = { .offset = 0xa2, .value = 0x28, },
+	[43] = { .offset = 0xa3, .value = 0x05, },
+	/* register 0xa4 is mode specific, but 0x80..0x84 works always */
+	[44] = { .offset = 0xa4, .value = 0x84, },
+	[45] = { .offset = 0xa5, .value = 0x00, },
+	[46] = { .offset = 0xa6, .value = 0x00, },
+	[47] = { .offset = 0xa7, .value = 0x00, },
+	[48] = { .offset = 0xa8, .value = 0x00, },
+	/* 0xa9 to 0xab are mode specific, but have no visible effect */
+	[49] = { .offset = 0xa9, .value = 0x04, },
+	[50] = { .offset = 0xaa, .value = 0x70, },
+	[51] = { .offset = 0xab, .value = 0x4f, },
+	[52] = { .offset = 0xac, .value = 0x00, },
+	[53] = { .offset = 0xad, .value = 0x00, },
+	[54] = { .offset = 0xb6, .value = 0x09, },
+	[55] = { .offset = 0xb7, .value = 0x03, },
+	/* b8,b9 are part of the mode-specific configuration */
+	[56] = { .offset = 0xba, .value = 0x00, },
+	[57] = { .offset = 0xbb, .value = 0x20, },
+	[58] = { .offset = 0xf3, .value = 0x90, },
+	[59] = { .offset = 0xf4, .value = 0x00, },
+	[60] = { .offset = 0xf7, .value = 0x88, },
+	/* f8 is mode specific, but the value does not matter */
+	[61] = { .offset = 0xf8, .value = 0x0a, },
+	[62] = { .offset = 0xf9, .value = 0x00, }
 };
 
 static const struct ns2501_reg regs_init[] = {
@@ -350,7 +378,7 @@ 
 
 struct ns2501_priv {
 	bool quiet;
-	const struct ns2501_reg *regs;
+	const struct ns2501_configuration *conf;
 };
 
 #define NSPTR(d) ((NS2501Ptr)(d->DriverPrivate.ptr))
@@ -534,6 +562,7 @@ 
 			    struct drm_display_mode *mode,
 			    struct drm_display_mode *adjusted_mode)
 {
+	const struct ns2501_configuration *conf;
 	struct ns2501_priv *ns = (struct ns2501_priv *)(dvo->dev_priv);
 	int mode_idx, i;
 
@@ -554,10 +583,44 @@ 
 	for (i = 0; i < ARRAY_SIZE(regs_init); i++)
 		ns2501_writeb(dvo, regs_init[i].offset, regs_init[i].value);
 
-	ns->regs = regs_1024x768[mode_idx];
-
-	for (i = 0; i < 84; i++)
-		ns2501_writeb(dvo, ns->regs[i].offset, ns->regs[i].value);
+	/* Write the mode-agnostic values */
+	for (i = 0; i < ARRAY_SIZE(mode_agnostic_values); i++)
+		ns2501_writeb(dvo, mode_agnostic_values[i].offset,
+				mode_agnostic_values[i].value);
+
+	/* Write now the mode-specific configuration */
+	conf = ns2501_modes + mode_idx;
+	ns->conf = conf;
+
+	ns2501_writeb(dvo, NS2501_REG8, conf->conf);
+	ns2501_writeb(dvo, NS2501_REG1B, conf->pll_a);
+	ns2501_writeb(dvo, NS2501_REG1C, conf->pll_b & 0xff);
+	ns2501_writeb(dvo, NS2501_REG1D, conf->pll_b >> 8);
+	ns2501_writeb(dvo, NS2501_REGC1, conf->hstart & 0xff);
+	ns2501_writeb(dvo, NS2501_REGC2, conf->hstart >> 8);
+	ns2501_writeb(dvo, NS2501_REGC3, conf->hstop & 0xff);
+	ns2501_writeb(dvo, NS2501_REGC4, conf->hstop >> 8);
+	ns2501_writeb(dvo, NS2501_REGC5, conf->vstart & 0xff);
+	ns2501_writeb(dvo, NS2501_REGC6, conf->vstart >> 8);
+	ns2501_writeb(dvo, NS2501_REGC7, conf->vstop & 0xff);
+	ns2501_writeb(dvo, NS2501_REGC8, conf->vstop >> 8);
+	ns2501_writeb(dvo, NS2501_REG80, conf->vsync & 0xff);
+	ns2501_writeb(dvo, NS2501_REG81, conf->vsync >> 8);
+	ns2501_writeb(dvo, NS2501_REG82, conf->vtotal & 0xff);
+	ns2501_writeb(dvo, NS2501_REG83, conf->vtotal >> 8);
+	ns2501_writeb(dvo, NS2501_REG98, conf->hpos & 0xff);
+	ns2501_writeb(dvo, NS2501_REG99, conf->hpos >> 8);
+	ns2501_writeb(dvo, NS2501_REG8E, conf->vpos & 0xff);
+	ns2501_writeb(dvo, NS2501_REG8F, conf->vpos >> 8);
+	ns2501_writeb(dvo, NS2501_REG9C, conf->voffs & 0xff);
+	ns2501_writeb(dvo, NS2501_REG9D, conf->voffs >> 8);
+	ns2501_writeb(dvo, NS2501_REGB8, conf->hscale & 0xff);
+	ns2501_writeb(dvo, NS2501_REGB9, conf->hscale >> 8);
+	ns2501_writeb(dvo, NS2501_REG10, conf->vscale & 0xff);
+	ns2501_writeb(dvo, NS2501_REG11, conf->vscale >> 8);
+	ns2501_writeb(dvo, NS2501_REGF9, conf->dither);
+	ns2501_writeb(dvo, NS2501_REG41, conf->syncb);
+	ns2501_writeb(dvo, NS2501_REGC0, conf->sync);
 }
 
 /* set the NS2501 power state */
@@ -579,34 +642,32 @@ 
 	DRM_DEBUG_KMS("Trying set the dpms of the DVO to %i\n", enable);
 
 	if (enable) {
-		if (WARN_ON(ns->regs[83].offset != 0x08 ||
-			    ns->regs[84].offset != 0x41 ||
-			    ns->regs[85].offset != 0xc0))
-			return;
-
-		ns2501_writeb(dvo, 0xc0, ns->regs[85].value | 0x08);
+		ns2501_writeb(dvo, NS2501_REGC0, ns->conf->sync | 0x08);
 
-		ns2501_writeb(dvo, 0x41, ns->regs[84].value);
+		ns2501_writeb(dvo, NS2501_REG41, ns->conf->syncb);
 
-		ns2501_writeb(dvo, 0x34, 0x01);
+		ns2501_writeb(dvo, NS2501_REG34, NS2501_34_ENABLE_OUTPUT);
 		msleep(15);
 
-		ns2501_writeb(dvo, 0x08, 0x35);
-		if (!(ns->regs[83].value & NS2501_8_BPAS))
-			ns2501_writeb(dvo, 0x08, 0x31);
+		ns2501_writeb(dvo, NS2501_REG8,
+				ns->conf->conf | NS2501_8_BPAS);
+		if (!(ns->conf->conf & NS2501_8_BPAS))
+			ns2501_writeb(dvo, NS2501_REG8, ns->conf->conf);
 		msleep(200);
 
-		ns2501_writeb(dvo, 0x34, 0x03);
+		ns2501_writeb(dvo, NS2501_REG34,
+			NS2501_34_ENABLE_OUTPUT | NS2501_34_ENABLE_BACKLIGHT);
 
-		ns2501_writeb(dvo, 0xc0, ns->regs[85].value);
+		ns2501_writeb(dvo, NS2501_REGC0, ns->conf->sync);
 	} else {
-		ns2501_writeb(dvo, 0x34, 0x01);
+		ns2501_writeb(dvo, NS2501_REG34, NS2501_34_ENABLE_OUTPUT);
 		msleep(200);
 
-		ns2501_writeb(dvo, 0x08, 0x34);
+		ns2501_writeb(dvo, NS2501_REG8, NS2501_8_VEN | NS2501_8_HEN |
+				NS2501_8_BPAS);
 		msleep(15);
 
-		ns2501_writeb(dvo, 0x34, 0x00);
+		ns2501_writeb(dvo, NS2501_REG34, 0x00);
 	}
 }
 

Comments

On Wed, Apr 15, 2015 at 12:02:09AM +0200, Thomas Richter wrote:
> Hi Daniel, hi Ville,
> 
> please find a patch attached for the NatSemi 2501 DVO found in the Fujitsu
> S6010 (and others). This patch
> includes proper definitions for some registers of the (undocumented) scaler
> of the DVO chip, and
> also enables dithering by default on all modes. This improves image quality
> significantly in the 32bit
> modes as it avoids stair cases due to quantization.
> 
> It should hopefully also open a door for future automatic mode computations.
> 
> What is still unclear is the proper configuration of the PLL of the chip. It
> seems to consist of a numerator/
> denominator pair in registers 1b,1c,1d, though its precise configuration is
> still a mystery.
> 
> Note also that the DVO configuration found in the previous kernel driver
> enabled the DVO bypass for
> the 1024x768 mode, and hence could not run enable dithering there either.
> The BIOS left no useful
> defaults for the scaler in this mode, so I had to obtain this by some
> computation and some try and error.
> 
> Unfortunately, it is still unclear which registers define the output (panel)
> configuration as I have only
> a single panel available for testing. A laptop with a larger panel using the
> 2501 would certainly be helpful
> to understand the rest of the registers.
> 
> Greetings,
>     Thomas
> 

> Signed-off-by: Thomas Richter <thor@math.tu-berlin.de>

Can you please move all your findings from your investigation into the
commit message here? Imo that's important information to keep on record.
One small style suggestion below, otherwise lgtm
-Daniel

> ---
> --- dvo_ns2501.c-org	2015-04-14 15:34:34.000000000 +0200
> +++ dvo_ns2501.c	2015-04-14 23:46:16.000000000 +0200
> @@ -60,6 +60,130 @@
>  
>  #define NS2501_REGC 0x0c
>  
> +/*
> + * The following registers are not part of the official datasheet
> + * and are the result of reverse engineering.
> + */
> +
> +/*
> + * Register c0 controls how the DVO synchronizes with
> + * its input.
> + */
> +#define NS2501_REGC0 0xc0
> +#define NS2501_C0_ENABLE (1<<0)	/* enable the DVO sync in general */
> +#define NS2501_C0_HSYNC (1<<1)	/* synchronize horizontal with input */
> +#define NS2501_C0_VSYNC (1<<2)	/* synchronize vertical with input */
> +#define NS2501_C0_RESET (1<<7)	/* reset the synchronization flip/flops */
> +
> +/*
> + * Register 41 is somehow related to the sync register and sync
> + * configuration. It should be 0x32 whenever regC0 is 0x05 (hsync off)
> + * and 0x00 otherwise.
> + */
> +#define NS2501_REG41 0x41
> +
> +/*
> + * this register controls the dithering of the DVO
> + * One bit enables it, the other define the dithering depth.
> + * The higher the value, the lower the dithering depth.
> + */
> +#define NS2501_F9_REG 0xf9
> +#define NS2501_F9_ENABLE (1<<0)		/* if set, dithering is enabled */
> +#define NS2501_F9_DITHER_MASK (0x7f<<1)	/* controls the dither depth */
> +#define NS2501_F9_DITHER_SHIFT 1	/* shifts the dither mask */
> +
> +/*
> + * PLL configuration register. This is a pair of registers,
> + * one single byte register at 1B, and a pair at 1C,1D.
> + * These registers are counters/dividers.
> + */
> +#define NS2501_REG1B 0x1b /* one byte PLL control register */
> +#define NS2501_REG1C 0x1c /* low-part of the second register */
> +#define NS2501_REG1D 0x1d /* high-part of the second register */
> +
> +/*
> + * Scaler control registers. Horizontal at b8,b9,
> + * vertical at 10,11. The scale factor is computed as
> + * 2^16/control-value. The low-byte comes first.
> + */
> +#define NS2501_REG10 0x10 /* low-byte vertical scaler */
> +#define NS2501_REG11 0x11 /* high-byte vertical scaler */
> +#define NS2501_REGB8 0xb8 /* low-byte horizontal scaler */
> +#define NS2501_REGB9 0xb9 /* high-byte horizontal scaler */
> +
> +/*
> + * Display window definition. This consists of four registers
> + * per dimension. One register pair defines the start of the
> + * display, one the end.
> + * As far as I understand, this defines the window within which
> + * the scaler samples the input.
> + */
> +#define NS2501_REGC1 0xc1 /* low-byte horizontal display start */
> +#define NS2501_REGC2 0xc2 /* high-byte horizontal display start */
> +#define NS2501_REGC3 0xc3 /* low-byte horizontal display stop */
> +#define NS2501_REGC4 0xc4 /* high-byte horizontal display stop */
> +#define NS2501_REGC5 0xc5 /* low-byte vertical display start */
> +#define NS2501_REGC6 0xc6 /* high-byte vertical display start */
> +#define NS2501_REGC7 0xc7 /* low-byte vertical display stop */
> +#define NS2501_REGC8 0xc8 /* high-byte vertical display stop */
> +
> +/*
> + * The following register pair seems to define the start of
> + * the vertical sync. If automatic syncing is enabled, and the
> + * register value defines a sync pulse that is later than the
> + * incoming sync, then the register value is ignored and the
> + * external hsync triggers the synchronization.
> + */
> +#define NS2501_REG80 0x80 /* low-byte vsync-start */
> +#define NS2501_REG81 0x81 /* high-byte vsync-start */
> +
> +/*
> + * The following register pair seems to define the total number
> + * of lines created at the output side of the scaler.
> + * This is again a low-high register pair.
> + */
> +#define NS2501_REG82 0x82 /* output display height, low byte */
> +#define NS2501_REG83 0x83 /* output display height, high byte */
> +
> +/*
> + * The following registers define the end of the front-porch
> + * in horizontal and vertical position and hence allow to shift
> + * the image left/right or up/down.
> + */
> +#define NS2501_REG98 0x98 /* horizontal start of display + 256, low */
> +#define NS2501_REG99 0x99 /* horizontal start of display + 256, high */
> +#define NS2501_REG8E 0x8e /* vertical start of the display, low byte */
> +#define NS2501_REG8F 0x8f /* vertical start of the display, high byte */
> +
> +/*
> + * The following register pair control the function of the
> + * backlight and the DVO output. To enable the corresponding
> + * function, the corresponding bit must be set in both registers.
> + */
> +#define NS2501_REG34 0x34 /* DVO enable functions, first register */
> +#define NS2501_REG35 0x35 /* DVO enable functions, second register */
> +#define NS2501_34_ENABLE_OUTPUT (1<<0) /* enable DVO output */
> +#define NS2501_34_ENABLE_BACKLIGHT (1<<1) /* enable backlight */
> +
> +/*
> + * Registers 9C and 9D define the vertical output offset
> + * of the visible region.
> + */
> +#define NS2501_REG9C 0x9c
> +#define NS2501_REG9D 0x9d
> +
> +/*
> + * The register 9F defines the dithering. This requires the
> + * scaler to be ON. Bit 0 enables dithering, the remaining
> + * bits control the depth of the dither. The higher the value,
> + * the LOWER the dithering amplitude. A good value seems to be
> + * 15 (total register value).
> + */
> +#define NS2501_REGF9 0xf9
> +#define NS2501_F9_ENABLE_DITHER (1<<0) /* enable dithering */
> +#define NS2501_F9_DITHER_MASK (0x7f<<1) /* dither masking */
> +#define NS2501_F9_DITHER_SHIFT 1	/* upshift of the dither mask */
> +
>  enum {
>  	MODE_640x480,
>  	MODE_800x600,
> @@ -72,274 +196,178 @@
>  };
>  
>  /*
> - * Magic values based on what the BIOS on
> - * Fujitsu-Siemens Lifebook S6010 programs (1024x768 panel).
> + * The following structure keeps the complete configuration of
> + * the DVO, given a specific output configuration.
> + * This is pretty much guess-work from reverse-engineering, so
> + * read all this with a grain of salt.
>   */
> -static const struct ns2501_reg regs_1024x768[][86] = {
> +struct ns2501_configuration {
> +	uint8_t sync;		/* configuration of the C0 register */
> +	uint8_t conf;		/* configuration register 8 */
> +	uint8_t syncb;		/* configuration register 41 */
> +	uint8_t	dither;		/* configuration of the dithering */
> +	uint8_t pll_a;		/* PLL configuration, register A, 1B */
> +	uint16_t pll_b;		/* PLL configuration, register B, 1C/1D */
> +	uint16_t hstart;	/* horizontal start, registers C1/C2 */
> +	uint16_t hstop;		/* horizontal total, registers C3/C4 */
> +	uint16_t vstart;	/* vertical start, registers C5/C6 */
> +	uint16_t vstop;		/* vertical total, registers C7/C8 */
> +	uint16_t vsync;         /* manual vertical sync start, 80/81 */
> +	uint16_t vtotal;        /* number of lines generated, 82/83 */
> +	uint16_t hpos;		/* horizontal position + 256, 98/99  */
> +	uint16_t vpos;		/* vertical position, 8e/8f */
> +	uint16_t voffs;		/* vertical output offset, 9c/9d */
> +	uint16_t hscale;	/* horizontal scaling factor, b8/b9 */
> +	uint16_t vscale;	/* vertical scaling factor, 10/11 */
> +};
> +
> +/*
> + * DVO configuration values, partially based on what the BIOS
> + * of the Fujitsu Lifebook S6010 writes into registers,
> + * partially found by manual tweaking. These configurations assume
> + * a 1024x768 panel.
> + */
> +static const struct ns2501_configuration ns2501_modes[] = {
>  	[MODE_640x480] = {
> -		[0] = { .offset = 0x0a, .value = 0x81, },
> -		[1] = { .offset = 0x18, .value = 0x07, },
> -		[2] = { .offset = 0x19, .value = 0x00, },
> -		[3] = { .offset = 0x1a, .value = 0x00, },
> -		[4] = { .offset = 0x1b, .value = 0x11, },
> -		[5] = { .offset = 0x1c, .value = 0x54, },
> -		[6] = { .offset = 0x1d, .value = 0x03, },
> -		[7] = { .offset = 0x1e, .value = 0x02, },
> -		[8] = { .offset = 0xf3, .value = 0x90, },
> -		[9] = { .offset = 0xf9, .value = 0x00, },
> -		[10] = { .offset = 0xc1, .value = 0x90, },
> -		[11] = { .offset = 0xc2, .value = 0x00, },
> -		[12] = { .offset = 0xc3, .value = 0x0f, },
> -		[13] = { .offset = 0xc4, .value = 0x03, },
> -		[14] = { .offset = 0xc5, .value = 0x16, },
> -		[15] = { .offset = 0xc6, .value = 0x00, },
> -		[16] = { .offset = 0xc7, .value = 0x02, },
> -		[17] = { .offset = 0xc8, .value = 0x02, },
> -		[18] = { .offset = 0xf4, .value = 0x00, },
> -		[19] = { .offset = 0x80, .value = 0xff, },
> -		[20] = { .offset = 0x81, .value = 0x07, },
> -		[21] = { .offset = 0x82, .value = 0x3d, },
> -		[22] = { .offset = 0x83, .value = 0x05, },
> -		[23] = { .offset = 0x94, .value = 0x00, },
> -		[24] = { .offset = 0x95, .value = 0x00, },
> -		[25] = { .offset = 0x96, .value = 0x05, },
> -		[26] = { .offset = 0x97, .value = 0x00, },
> -		[27] = { .offset = 0x9a, .value = 0x88, },
> -		[28] = { .offset = 0x9b, .value = 0x00, },
> -		[29] = { .offset = 0x98, .value = 0x00, },
> -		[30] = { .offset = 0x99, .value = 0x00, },
> -		[31] = { .offset = 0xf7, .value = 0x88, },
> -		[32] = { .offset = 0xf8, .value = 0x0a, },
> -		[33] = { .offset = 0x9c, .value = 0x24, },
> -		[34] = { .offset = 0x9d, .value = 0x00, },
> -		[35] = { .offset = 0x9e, .value = 0x25, },
> -		[36] = { .offset = 0x9f, .value = 0x03, },
> -		[37] = { .offset = 0xa0, .value = 0x28, },
> -		[38] = { .offset = 0xa1, .value = 0x01, },
> -		[39] = { .offset = 0xa2, .value = 0x28, },
> -		[40] = { .offset = 0xa3, .value = 0x05, },
> -		[41] = { .offset = 0xb6, .value = 0x09, },
> -		[42] = { .offset = 0xb8, .value = 0x00, },
> -		[43] = { .offset = 0xb9, .value = 0xa0, },
> -		[44] = { .offset = 0xba, .value = 0x00, },
> -		[45] = { .offset = 0xbb, .value = 0x20, },
> -		[46] = { .offset = 0x10, .value = 0x00, },
> -		[47] = { .offset = 0x11, .value = 0xa0, },
> -		[48] = { .offset = 0x12, .value = 0x02, },
> -		[49] = { .offset = 0x20, .value = 0x00, },
> -		[50] = { .offset = 0x22, .value = 0x00, },
> -		[51] = { .offset = 0x23, .value = 0x00, },
> -		[52] = { .offset = 0x24, .value = 0x00, },
> -		[53] = { .offset = 0x25, .value = 0x00, },
> -		[54] = { .offset = 0x8c, .value = 0x10, },
> -		[55] = { .offset = 0x8d, .value = 0x02, },
> -		[56] = { .offset = 0x8e, .value = 0x10, },
> -		[57] = { .offset = 0x8f, .value = 0x00, },
> -		[58] = { .offset = 0x90, .value = 0xff, },
> -		[59] = { .offset = 0x91, .value = 0x07, },
> -		[60] = { .offset = 0x92, .value = 0xa0, },
> -		[61] = { .offset = 0x93, .value = 0x02, },
> -		[62] = { .offset = 0xa5, .value = 0x00, },
> -		[63] = { .offset = 0xa6, .value = 0x00, },
> -		[64] = { .offset = 0xa7, .value = 0x00, },
> -		[65] = { .offset = 0xa8, .value = 0x00, },
> -		[66] = { .offset = 0xa9, .value = 0x04, },
> -		[67] = { .offset = 0xaa, .value = 0x70, },
> -		[68] = { .offset = 0xab, .value = 0x4f, },
> -		[69] = { .offset = 0xac, .value = 0x00, },
> -		[70] = { .offset = 0xa4, .value = 0x84, },
> -		[71] = { .offset = 0x7e, .value = 0x18, },
> -		[72] = { .offset = 0x84, .value = 0x00, },
> -		[73] = { .offset = 0x85, .value = 0x00, },
> -		[74] = { .offset = 0x86, .value = 0x00, },
> -		[75] = { .offset = 0x87, .value = 0x00, },
> -		[76] = { .offset = 0x88, .value = 0x00, },
> -		[77] = { .offset = 0x89, .value = 0x00, },
> -		[78] = { .offset = 0x8a, .value = 0x00, },
> -		[79] = { .offset = 0x8b, .value = 0x00, },
> -		[80] = { .offset = 0x26, .value = 0x00, },
> -		[81] = { .offset = 0x27, .value = 0x00, },
> -		[82] = { .offset = 0xad, .value = 0x00, },
> -		[83] = { .offset = 0x08, .value = 0x30, }, /* 0x31 */
> -		[84] = { .offset = 0x41, .value = 0x00, },
> -		[85] = { .offset = 0xc0, .value = 0x05, },
> +		.sync	= NS2501_C0_ENABLE | NS2501_C0_VSYNC,
> +		.conf	= NS2501_8_VEN | NS2501_8_HEN | NS2501_8_PD,
> +		.syncb	= 0x32,
> +		.dither	= 15,
> +		.pll_a	= 0x11,
> +		.pll_b	= 0x354,
> +		.hstart	= 0x90,
> +		.hstop	= 0x30f,
> +		.vstart	= 0x16,
> +		.vstop	= 0x202,
> +		.vsync	= 0x7ff, /* actually, ignored with this config */
> +		.vtotal	= 0x53d,
> +		.hpos	= 0x0,
> +		.vpos	= 0x10,
> +		.voffs	= 0x24,
> +		.hscale	= 0xa000,
> +		.vscale	= 0xa000

I think all the timing values above would be much clearer in decimal
instead of hex. At least everywhere else we do print out like that
everywhere else.

>  	},
>  	[MODE_800x600] = {
> -		[0] = { .offset = 0x0a, .value = 0x81, },
> -		[1] = { .offset = 0x18, .value = 0x07, },
> -		[2] = { .offset = 0x19, .value = 0x00, },
> -		[3] = { .offset = 0x1a, .value = 0x00, },
> -		[4] = { .offset = 0x1b, .value = 0x19, },
> -		[5] = { .offset = 0x1c, .value = 0x64, },
> -		[6] = { .offset = 0x1d, .value = 0x02, },
> -		[7] = { .offset = 0x1e, .value = 0x02, },
> -		[8] = { .offset = 0xf3, .value = 0x90, },
> -		[9] = { .offset = 0xf9, .value = 0x00, },
> -		[10] = { .offset = 0xc1, .value = 0xd7, },
> -		[11] = { .offset = 0xc2, .value = 0x00, },
> -		[12] = { .offset = 0xc3, .value = 0xf8, },
> -		[13] = { .offset = 0xc4, .value = 0x03, },
> -		[14] = { .offset = 0xc5, .value = 0x1a, },
> -		[15] = { .offset = 0xc6, .value = 0x00, },
> -		[16] = { .offset = 0xc7, .value = 0x73, },
> -		[17] = { .offset = 0xc8, .value = 0x02, },
> -		[18] = { .offset = 0xf4, .value = 0x00, },
> -		[19] = { .offset = 0x80, .value = 0x27, },
> -		[20] = { .offset = 0x81, .value = 0x03, },
> -		[21] = { .offset = 0x82, .value = 0x41, },
> -		[22] = { .offset = 0x83, .value = 0x05, },
> -		[23] = { .offset = 0x94, .value = 0x00, },
> -		[24] = { .offset = 0x95, .value = 0x00, },
> -		[25] = { .offset = 0x96, .value = 0x05, },
> -		[26] = { .offset = 0x97, .value = 0x00, },
> -		[27] = { .offset = 0x9a, .value = 0x88, },
> -		[28] = { .offset = 0x9b, .value = 0x00, },
> -		[29] = { .offset = 0x98, .value = 0x00, },
> -		[30] = { .offset = 0x99, .value = 0x00, },
> -		[31] = { .offset = 0xf7, .value = 0x88, },
> -		[32] = { .offset = 0xf8, .value = 0x06, },
> -		[33] = { .offset = 0x9c, .value = 0x23, },
> -		[34] = { .offset = 0x9d, .value = 0x00, },
> -		[35] = { .offset = 0x9e, .value = 0x25, },
> -		[36] = { .offset = 0x9f, .value = 0x03, },
> -		[37] = { .offset = 0xa0, .value = 0x28, },
> -		[38] = { .offset = 0xa1, .value = 0x01, },
> -		[39] = { .offset = 0xa2, .value = 0x28, },
> -		[40] = { .offset = 0xa3, .value = 0x05, },
> -		[41] = { .offset = 0xb6, .value = 0x09, },
> -		[42] = { .offset = 0xb8, .value = 0x30, },
> -		[43] = { .offset = 0xb9, .value = 0xc8, },
> -		[44] = { .offset = 0xba, .value = 0x00, },
> -		[45] = { .offset = 0xbb, .value = 0x20, },
> -		[46] = { .offset = 0x10, .value = 0x20, },
> -		[47] = { .offset = 0x11, .value = 0xc8, },
> -		[48] = { .offset = 0x12, .value = 0x02, },
> -		[49] = { .offset = 0x20, .value = 0x00, },
> -		[50] = { .offset = 0x22, .value = 0x00, },
> -		[51] = { .offset = 0x23, .value = 0x00, },
> -		[52] = { .offset = 0x24, .value = 0x00, },
> -		[53] = { .offset = 0x25, .value = 0x00, },
> -		[54] = { .offset = 0x8c, .value = 0x10, },
> -		[55] = { .offset = 0x8d, .value = 0x02, },
> -		[56] = { .offset = 0x8e, .value = 0x04, },
> -		[57] = { .offset = 0x8f, .value = 0x00, },
> -		[58] = { .offset = 0x90, .value = 0xff, },
> -		[59] = { .offset = 0x91, .value = 0x07, },
> -		[60] = { .offset = 0x92, .value = 0xa0, },
> -		[61] = { .offset = 0x93, .value = 0x02, },
> -		[62] = { .offset = 0xa5, .value = 0x00, },
> -		[63] = { .offset = 0xa6, .value = 0x00, },
> -		[64] = { .offset = 0xa7, .value = 0x00, },
> -		[65] = { .offset = 0xa8, .value = 0x00, },
> -		[66] = { .offset = 0xa9, .value = 0x83, },
> -		[67] = { .offset = 0xaa, .value = 0x40, },
> -		[68] = { .offset = 0xab, .value = 0x32, },
> -		[69] = { .offset = 0xac, .value = 0x00, },
> -		[70] = { .offset = 0xa4, .value = 0x80, },
> -		[71] = { .offset = 0x7e, .value = 0x18, },
> -		[72] = { .offset = 0x84, .value = 0x00, },
> -		[73] = { .offset = 0x85, .value = 0x00, },
> -		[74] = { .offset = 0x86, .value = 0x00, },
> -		[75] = { .offset = 0x87, .value = 0x00, },
> -		[76] = { .offset = 0x88, .value = 0x00, },
> -		[77] = { .offset = 0x89, .value = 0x00, },
> -		[78] = { .offset = 0x8a, .value = 0x00, },
> -		[79] = { .offset = 0x8b, .value = 0x00, },
> -		[80] = { .offset = 0x26, .value = 0x00, },
> -		[81] = { .offset = 0x27, .value = 0x00, },
> -		[82] = { .offset = 0xad, .value = 0x00, },
> -		[83] = { .offset = 0x08, .value = 0x30, }, /* 0x31 */
> -		[84] = { .offset = 0x41, .value = 0x00, },
> -		[85] = { .offset = 0xc0, .value = 0x07, },
> +		.sync	= NS2501_C0_ENABLE |
> +			  NS2501_C0_HSYNC | NS2501_C0_VSYNC,
> +		.conf   = NS2501_8_VEN | NS2501_8_HEN | NS2501_8_PD,
> +		.syncb	= 0x00,
> +		.dither	= 15,
> +		.pll_a	= 0x19,
> +		.pll_b	= 0x264,
> +		.hstart	= 0xd7,
> +		.hstop	= 0x3f8,
> +		.vstart	= 0x1a,
> +		.vstop	= 0x273,
> +		.vsync	= 0x327,
> +		.vtotal	= 0x53d,
> +		.hpos	= 0x0,
> +		.vpos	= 0x4,
> +		.voffs	= 0x23,
> +		.hscale	= 0xc830,
> +		.vscale	= 0xc820
>  	},
>  	[MODE_1024x768] = {
> -		[0] = { .offset = 0x0a, .value = 0x81, },
> -		[1] = { .offset = 0x18, .value = 0x07, },
> -		[2] = { .offset = 0x19, .value = 0x00, },
> -		[3] = { .offset = 0x1a, .value = 0x00, },
> -		[4] = { .offset = 0x1b, .value = 0x11, },
> -		[5] = { .offset = 0x1c, .value = 0x54, },
> -		[6] = { .offset = 0x1d, .value = 0x03, },
> -		[7] = { .offset = 0x1e, .value = 0x02, },
> -		[8] = { .offset = 0xf3, .value = 0x90, },
> -		[9] = { .offset = 0xf9, .value = 0x00, },
> -		[10] = { .offset = 0xc1, .value = 0x90, },
> -		[11] = { .offset = 0xc2, .value = 0x00, },
> -		[12] = { .offset = 0xc3, .value = 0x0f, },
> -		[13] = { .offset = 0xc4, .value = 0x03, },
> -		[14] = { .offset = 0xc5, .value = 0x16, },
> -		[15] = { .offset = 0xc6, .value = 0x00, },
> -		[16] = { .offset = 0xc7, .value = 0x02, },
> -		[17] = { .offset = 0xc8, .value = 0x02, },
> -		[18] = { .offset = 0xf4, .value = 0x00, },
> -		[19] = { .offset = 0x80, .value = 0xff, },
> -		[20] = { .offset = 0x81, .value = 0x07, },
> -		[21] = { .offset = 0x82, .value = 0x3d, },
> -		[22] = { .offset = 0x83, .value = 0x05, },
> -		[23] = { .offset = 0x94, .value = 0x00, },
> -		[24] = { .offset = 0x95, .value = 0x00, },
> -		[25] = { .offset = 0x96, .value = 0x05, },
> -		[26] = { .offset = 0x97, .value = 0x00, },
> -		[27] = { .offset = 0x9a, .value = 0x88, },
> -		[28] = { .offset = 0x9b, .value = 0x00, },
> -		[29] = { .offset = 0x98, .value = 0x00, },
> -		[30] = { .offset = 0x99, .value = 0x00, },
> -		[31] = { .offset = 0xf7, .value = 0x88, },
> -		[32] = { .offset = 0xf8, .value = 0x0a, },
> -		[33] = { .offset = 0x9c, .value = 0x24, },
> -		[34] = { .offset = 0x9d, .value = 0x00, },
> -		[35] = { .offset = 0x9e, .value = 0x25, },
> -		[36] = { .offset = 0x9f, .value = 0x03, },
> -		[37] = { .offset = 0xa0, .value = 0x28, },
> -		[38] = { .offset = 0xa1, .value = 0x01, },
> -		[39] = { .offset = 0xa2, .value = 0x28, },
> -		[40] = { .offset = 0xa3, .value = 0x05, },
> -		[41] = { .offset = 0xb6, .value = 0x09, },
> -		[42] = { .offset = 0xb8, .value = 0x00, },
> -		[43] = { .offset = 0xb9, .value = 0xa0, },
> -		[44] = { .offset = 0xba, .value = 0x00, },
> -		[45] = { .offset = 0xbb, .value = 0x20, },
> -		[46] = { .offset = 0x10, .value = 0x00, },
> -		[47] = { .offset = 0x11, .value = 0xa0, },
> -		[48] = { .offset = 0x12, .value = 0x02, },
> -		[49] = { .offset = 0x20, .value = 0x00, },
> -		[50] = { .offset = 0x22, .value = 0x00, },
> -		[51] = { .offset = 0x23, .value = 0x00, },
> -		[52] = { .offset = 0x24, .value = 0x00, },
> -		[53] = { .offset = 0x25, .value = 0x00, },
> -		[54] = { .offset = 0x8c, .value = 0x10, },
> -		[55] = { .offset = 0x8d, .value = 0x02, },
> -		[56] = { .offset = 0x8e, .value = 0x10, },
> -		[57] = { .offset = 0x8f, .value = 0x00, },
> -		[58] = { .offset = 0x90, .value = 0xff, },
> -		[59] = { .offset = 0x91, .value = 0x07, },
> -		[60] = { .offset = 0x92, .value = 0xa0, },
> -		[61] = { .offset = 0x93, .value = 0x02, },
> -		[62] = { .offset = 0xa5, .value = 0x00, },
> -		[63] = { .offset = 0xa6, .value = 0x00, },
> -		[64] = { .offset = 0xa7, .value = 0x00, },
> -		[65] = { .offset = 0xa8, .value = 0x00, },
> -		[66] = { .offset = 0xa9, .value = 0x04, },
> -		[67] = { .offset = 0xaa, .value = 0x70, },
> -		[68] = { .offset = 0xab, .value = 0x4f, },
> -		[69] = { .offset = 0xac, .value = 0x00, },
> -		[70] = { .offset = 0xa4, .value = 0x84, },
> -		[71] = { .offset = 0x7e, .value = 0x18, },
> -		[72] = { .offset = 0x84, .value = 0x00, },
> -		[73] = { .offset = 0x85, .value = 0x00, },
> -		[74] = { .offset = 0x86, .value = 0x00, },
> -		[75] = { .offset = 0x87, .value = 0x00, },
> -		[76] = { .offset = 0x88, .value = 0x00, },
> -		[77] = { .offset = 0x89, .value = 0x00, },
> -		[78] = { .offset = 0x8a, .value = 0x00, },
> -		[79] = { .offset = 0x8b, .value = 0x00, },
> -		[80] = { .offset = 0x26, .value = 0x00, },
> -		[81] = { .offset = 0x27, .value = 0x00, },
> -		[82] = { .offset = 0xad, .value = 0x00, },
> -		[83] = { .offset = 0x08, .value = 0x34, }, /* 0x35 */
> -		[84] = { .offset = 0x41, .value = 0x00, },
> -		[85] = { .offset = 0xc0, .value = 0x01, },
> -	},
> +		.sync	= NS2501_C0_ENABLE | NS2501_C0_VSYNC,
> +		.conf   = NS2501_8_VEN | NS2501_8_HEN | NS2501_8_PD,
> +		.syncb	= 0x32,
> +		.dither	= 15,
> +		.pll_a	= 0x0b,
> +		.pll_b	= 0x546,
> +		.hstart	= 0x114,
> +		.hstop	= 0x513,
> +		.vstart	= 0x0f,
> +		.vstop	= 0x420,
> +		.vsync	= 0x7ff,
> +		.vtotal	= 0x53d,
> +		.hpos	= 0x0,
> +		.vpos	= 0x07,
> +		.voffs	= 0x1b,
> +		.hscale	= 0xffff,
> +		.vscale	= 0xffff
> +	}
> +};
> +
> +/*
> + * Other configuration values left by the BIOS of the
> + * Fujitsu S6010 in the DVO control registers. Their
> + * value does not depend on the BIOS and their meaning
> + * is unknown.
> + */
> +
> +static const struct ns2501_reg mode_agnostic_values[] = {
> +	/* 08 is mode specific */
> +	[0] = { .offset = 0x0a, .value = 0x81, },
> +	/* 10,11 are part of the mode specific configuration */
> +	[1] = { .offset = 0x12, .value = 0x02, },
> +	[2] = { .offset = 0x18, .value = 0x07, },
> +	[3] = { .offset = 0x19, .value = 0x00, },
> +	[4] = { .offset = 0x1a, .value = 0x00, }, /* PLL?, ignored */
> +	/* 1b,1c,1d are part of the mode specific configuration */
> +	[5] = { .offset = 0x1e, .value = 0x02, },
> +	[6] = { .offset = 0x1f, .value = 0x40, },
> +	[7] = { .offset = 0x20, .value = 0x00, },
> +	[8] = { .offset = 0x21, .value = 0x00, },
> +	[9] = { .offset = 0x22, .value = 0x00, },
> +	[10] = { .offset = 0x23, .value = 0x00, },
> +	[11] = { .offset = 0x24, .value = 0x00, },
> +	[12] = { .offset = 0x25, .value = 0x00, },
> +	[13] = { .offset = 0x26, .value = 0x00, },
> +	[14] = { .offset = 0x27, .value = 0x00, },
> +	[15] = { .offset = 0x7e, .value = 0x18, },
> +	/* 80-84 are part of the mode-specific configuration */
> +	[16] = { .offset = 0x84, .value = 0x00, },
> +	[17] = { .offset = 0x85, .value = 0x00, },
> +	[18] = { .offset = 0x86, .value = 0x00, },
> +	[19] = { .offset = 0x87, .value = 0x00, },
> +	[20] = { .offset = 0x88, .value = 0x00, },
> +	[21] = { .offset = 0x89, .value = 0x00, },
> +	[22] = { .offset = 0x8a, .value = 0x00, },
> +	[23] = { .offset = 0x8b, .value = 0x00, },
> +	[24] = { .offset = 0x8c, .value = 0x10, },
> +	[25] = { .offset = 0x8d, .value = 0x02, },
> +	/* 8e,8f are part of the mode-specific configuration */
> +	[26] = { .offset = 0x90, .value = 0xff, },
> +	[27] = { .offset = 0x91, .value = 0x07, },
> +	[28] = { .offset = 0x92, .value = 0xa0, },
> +	[29] = { .offset = 0x93, .value = 0x02, },
> +	[30] = { .offset = 0x94, .value = 0x00, },
> +	[31] = { .offset = 0x95, .value = 0x00, },
> +	[32] = { .offset = 0x96, .value = 0x05, },
> +	[33] = { .offset = 0x97, .value = 0x00, },
> +	/* 98,99 are part of the mode-specific configuration */
> +	[34] = { .offset = 0x9a, .value = 0x88, },
> +	[35] = { .offset = 0x9b, .value = 0x00, },
> +	/* 9c,9d are part of the mode-specific configuration */
> +	[38] = { .offset = 0x9e, .value = 0x25, },
> +	[39] = { .offset = 0x9f, .value = 0x03, },
> +	[40] = { .offset = 0xa0, .value = 0x28, },
> +	[41] = { .offset = 0xa1, .value = 0x01, },
> +	[42] = { .offset = 0xa2, .value = 0x28, },
> +	[43] = { .offset = 0xa3, .value = 0x05, },
> +	/* register 0xa4 is mode specific, but 0x80..0x84 works always */
> +	[44] = { .offset = 0xa4, .value = 0x84, },
> +	[45] = { .offset = 0xa5, .value = 0x00, },
> +	[46] = { .offset = 0xa6, .value = 0x00, },
> +	[47] = { .offset = 0xa7, .value = 0x00, },
> +	[48] = { .offset = 0xa8, .value = 0x00, },
> +	/* 0xa9 to 0xab are mode specific, but have no visible effect */
> +	[49] = { .offset = 0xa9, .value = 0x04, },
> +	[50] = { .offset = 0xaa, .value = 0x70, },
> +	[51] = { .offset = 0xab, .value = 0x4f, },
> +	[52] = { .offset = 0xac, .value = 0x00, },
> +	[53] = { .offset = 0xad, .value = 0x00, },
> +	[54] = { .offset = 0xb6, .value = 0x09, },
> +	[55] = { .offset = 0xb7, .value = 0x03, },
> +	/* b8,b9 are part of the mode-specific configuration */
> +	[56] = { .offset = 0xba, .value = 0x00, },
> +	[57] = { .offset = 0xbb, .value = 0x20, },
> +	[58] = { .offset = 0xf3, .value = 0x90, },
> +	[59] = { .offset = 0xf4, .value = 0x00, },
> +	[60] = { .offset = 0xf7, .value = 0x88, },
> +	/* f8 is mode specific, but the value does not matter */
> +	[61] = { .offset = 0xf8, .value = 0x0a, },
> +	[62] = { .offset = 0xf9, .value = 0x00, }
>  };
>  
>  static const struct ns2501_reg regs_init[] = {
> @@ -350,7 +378,7 @@
>  
>  struct ns2501_priv {
>  	bool quiet;
> -	const struct ns2501_reg *regs;
> +	const struct ns2501_configuration *conf;
>  };
>  
>  #define NSPTR(d) ((NS2501Ptr)(d->DriverPrivate.ptr))
> @@ -534,6 +562,7 @@
>  			    struct drm_display_mode *mode,
>  			    struct drm_display_mode *adjusted_mode)
>  {
> +	const struct ns2501_configuration *conf;
>  	struct ns2501_priv *ns = (struct ns2501_priv *)(dvo->dev_priv);
>  	int mode_idx, i;
>  
> @@ -554,10 +583,44 @@
>  	for (i = 0; i < ARRAY_SIZE(regs_init); i++)
>  		ns2501_writeb(dvo, regs_init[i].offset, regs_init[i].value);
>  
> -	ns->regs = regs_1024x768[mode_idx];
> -
> -	for (i = 0; i < 84; i++)
> -		ns2501_writeb(dvo, ns->regs[i].offset, ns->regs[i].value);
> +	/* Write the mode-agnostic values */
> +	for (i = 0; i < ARRAY_SIZE(mode_agnostic_values); i++)
> +		ns2501_writeb(dvo, mode_agnostic_values[i].offset,
> +				mode_agnostic_values[i].value);
> +
> +	/* Write now the mode-specific configuration */
> +	conf = ns2501_modes + mode_idx;
> +	ns->conf = conf;
> +
> +	ns2501_writeb(dvo, NS2501_REG8, conf->conf);
> +	ns2501_writeb(dvo, NS2501_REG1B, conf->pll_a);
> +	ns2501_writeb(dvo, NS2501_REG1C, conf->pll_b & 0xff);
> +	ns2501_writeb(dvo, NS2501_REG1D, conf->pll_b >> 8);
> +	ns2501_writeb(dvo, NS2501_REGC1, conf->hstart & 0xff);
> +	ns2501_writeb(dvo, NS2501_REGC2, conf->hstart >> 8);
> +	ns2501_writeb(dvo, NS2501_REGC3, conf->hstop & 0xff);
> +	ns2501_writeb(dvo, NS2501_REGC4, conf->hstop >> 8);
> +	ns2501_writeb(dvo, NS2501_REGC5, conf->vstart & 0xff);
> +	ns2501_writeb(dvo, NS2501_REGC6, conf->vstart >> 8);
> +	ns2501_writeb(dvo, NS2501_REGC7, conf->vstop & 0xff);
> +	ns2501_writeb(dvo, NS2501_REGC8, conf->vstop >> 8);
> +	ns2501_writeb(dvo, NS2501_REG80, conf->vsync & 0xff);
> +	ns2501_writeb(dvo, NS2501_REG81, conf->vsync >> 8);
> +	ns2501_writeb(dvo, NS2501_REG82, conf->vtotal & 0xff);
> +	ns2501_writeb(dvo, NS2501_REG83, conf->vtotal >> 8);
> +	ns2501_writeb(dvo, NS2501_REG98, conf->hpos & 0xff);
> +	ns2501_writeb(dvo, NS2501_REG99, conf->hpos >> 8);
> +	ns2501_writeb(dvo, NS2501_REG8E, conf->vpos & 0xff);
> +	ns2501_writeb(dvo, NS2501_REG8F, conf->vpos >> 8);
> +	ns2501_writeb(dvo, NS2501_REG9C, conf->voffs & 0xff);
> +	ns2501_writeb(dvo, NS2501_REG9D, conf->voffs >> 8);
> +	ns2501_writeb(dvo, NS2501_REGB8, conf->hscale & 0xff);
> +	ns2501_writeb(dvo, NS2501_REGB9, conf->hscale >> 8);
> +	ns2501_writeb(dvo, NS2501_REG10, conf->vscale & 0xff);
> +	ns2501_writeb(dvo, NS2501_REG11, conf->vscale >> 8);
> +	ns2501_writeb(dvo, NS2501_REGF9, conf->dither);
> +	ns2501_writeb(dvo, NS2501_REG41, conf->syncb);
> +	ns2501_writeb(dvo, NS2501_REGC0, conf->sync);
>  }
>  
>  /* set the NS2501 power state */
> @@ -579,34 +642,32 @@
>  	DRM_DEBUG_KMS("Trying set the dpms of the DVO to %i\n", enable);
>  
>  	if (enable) {
> -		if (WARN_ON(ns->regs[83].offset != 0x08 ||
> -			    ns->regs[84].offset != 0x41 ||
> -			    ns->regs[85].offset != 0xc0))
> -			return;
> -
> -		ns2501_writeb(dvo, 0xc0, ns->regs[85].value | 0x08);
> +		ns2501_writeb(dvo, NS2501_REGC0, ns->conf->sync | 0x08);
>  
> -		ns2501_writeb(dvo, 0x41, ns->regs[84].value);
> +		ns2501_writeb(dvo, NS2501_REG41, ns->conf->syncb);
>  
> -		ns2501_writeb(dvo, 0x34, 0x01);
> +		ns2501_writeb(dvo, NS2501_REG34, NS2501_34_ENABLE_OUTPUT);
>  		msleep(15);
>  
> -		ns2501_writeb(dvo, 0x08, 0x35);
> -		if (!(ns->regs[83].value & NS2501_8_BPAS))
> -			ns2501_writeb(dvo, 0x08, 0x31);
> +		ns2501_writeb(dvo, NS2501_REG8,
> +				ns->conf->conf | NS2501_8_BPAS);
> +		if (!(ns->conf->conf & NS2501_8_BPAS))
> +			ns2501_writeb(dvo, NS2501_REG8, ns->conf->conf);
>  		msleep(200);
>  
> -		ns2501_writeb(dvo, 0x34, 0x03);
> +		ns2501_writeb(dvo, NS2501_REG34,
> +			NS2501_34_ENABLE_OUTPUT | NS2501_34_ENABLE_BACKLIGHT);
>  
> -		ns2501_writeb(dvo, 0xc0, ns->regs[85].value);
> +		ns2501_writeb(dvo, NS2501_REGC0, ns->conf->sync);
>  	} else {
> -		ns2501_writeb(dvo, 0x34, 0x01);
> +		ns2501_writeb(dvo, NS2501_REG34, NS2501_34_ENABLE_OUTPUT);
>  		msleep(200);
>  
> -		ns2501_writeb(dvo, 0x08, 0x34);
> +		ns2501_writeb(dvo, NS2501_REG8, NS2501_8_VEN | NS2501_8_HEN |
> +				NS2501_8_BPAS);
>  		msleep(15);
>  
> -		ns2501_writeb(dvo, 0x34, 0x00);
> +		ns2501_writeb(dvo, NS2501_REG34, 0x00);
>  	}
>  }
>