drivers: video: ov7670: update the camera init sequence

The previous initialization sequence fails to configure the module
properly. Update the sequence using the code provided by vendor.
The update is verified using the FRDM-MCXN947 SmartDMA camera case
under samples/drivers/video/capture.

Signed-off-by: Kate Wang <[email protected]>

Author: KATE-WANG-NXP

drivers/video/ov7670.c

@@ -219,21 +219,37 @@ static const struct ov7670_reg ov7670_init_regtbl[] = {
 	{OV7670_MVFP, 0x00}, /* MVFP: Mirror/VFlip,Normal image */
 
 	/* configure the output timing */
-	/* Free running PCLK, default VSYNC, HSYNC and PCLK */
-	{OV7670_COM10, 0x00}, /* COM10 */
+	/* PCLK does not toggle during horizontal blank, one PCLK, one pixel */
+	{OV7670_COM10, 0x20}, /* COM10 */
 	{OV7670_COM12, 0x00}, /* COM12,No HREF when VSYNC is low */
 	/* Brightness Control, with signal -128 to +128, 0x00 is middle value */
 	{OV7670_BRIGHT, 0x2f},
 
 	/* Internal clock pre-scalar,F(internal clock) = F(input clock)/(Bit[5:0]+1) */
-	{OV7670_CLKRC, 0x80}, /* Clock Div, Input/(n+1), bit6 set to 1 to disable divider */
+	{OV7670_CLKRC, 0x81}, /* Clock Div, Input/(n+1), bit6 set to 1 to disable divider */
+
+	/* SCALING_PCLK_DIV */
+	/* 0: Enable clock divider, 010: Divided by 4 */
+	{OV7670_SCALING_PCLK_DIV, 0xF1},
+	/* Common Control 14, Bit[4]: DCW and scaling PCLK enable, Bit[3]: Manual scaling */
+	{OV7670_COM14, 0x19},
+	/* Common Control 3, Bit[2]: DCW enable, Bit[3]: Scale enable */
+	{OV7670_COM3, 0x04},
 
 	/* DBLV,Bit[7:6]: PLL control */
 	/* 0:Bypass PLL, 40: Input clock x4  , 80: Input clock x6  ,C0: Input clock x8 */
-	{OV7670_DBLV, 0x00},
+	{OV7670_DBLV, 0x40},
+
+	/* test pattern, useful in some case */
+	{OV7670_SCALING_XSC, 0x3A},
+	{OV7670_SCALING_YSC, 0x35},
+
+	/* DCW Control */
+	{OV7670_SCALING_DCWCTR, 0x11},
 
 	/* Output Drive Capability */
 	{OV7670_COM2, 0x00}, /* Common Control 2, Output Drive Capability: 1x */
+	{OV7670_SCALING_PCLK_DELAY, 0x02},
 	{OV7670_BD50MAX, 0x05},
 	{OV7670_BD60MAX, 0x07},
 	{OV7670_HAECC7, 0x94},
@@ -265,13 +281,13 @@ static const struct ov7670_reg ov7670_init_regtbl[] = {
 
 	/* display , need retain */
 	{OV7670_COM15, 0xD0}, /* Common Control 15 */
-	{OV7670_TSLB, 0x04},  /* Reserved */
+	{OV7670_TSLB, 0x0C},  /* Line Buffer Test Option */
 	{OV7670_COM13, 0x80}, /* Common Control 13 */
 	{OV7670_MANU, 0x11},  /* Manual U Value */
 	{OV7670_MANV, 0xFF},  /* Manual V Value */
 	/* config the output window data, this can be configed later */
-	{OV7670_HSTART, 0x16}, /*  HSTART */
-	{OV7670_HSTOP, 0x04},  /*  HSTOP */
+	{OV7670_HSTART, 0x15}, /*  HSTART */
+	{OV7670_HSTOP, 0x03},  /*  HSTOP */
 	{OV7670_VSTRT, 0x02},  /*  VSTRT */
 	{OV7670_VSTOP, 0x7a},  /*  VSTOP */
 	{OV7670_HREF, 0x80},   /*  HREF */