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reform: retry reading edid a bunch of times

When masquerading as linux, uboot resets the lcdif
and mipidsi bridge. This causes some glitching with
the edid reading, so try a bunch of times.

--- a/sys/src/9/imx8/lcd.c

+++ b/sys/src/9/imx8/lcd.c

@@ -638,20 +638,22 @@

 {

 	static uchar edid[128];

 	static I2Cdev aux;

+	int i;

-	aux.bus = bridge->bus;

+	/* enable passthru mode for address 0x50 (EDID) */

 	aux.addr = 0x50;

+	aux.bus = bridge->bus;

 	aux.subaddr = 1;

 	aux.size = sizeof(edid);

-

-	/* enable passthru mode for address 0x50 (EDID) */

 	i2cwritebyte(bridge, 0x60, aux.addr<<1 | 1);

 	addi2cdev(&aux);

-	if(i2crecv(&aux, edid, sizeof(edid), 0) != sizeof(edid))

-		return "i2crecv failed to get edid bytes";

-

-	return parseedid128(mode, edid);

+	for(i = 0; i < 10; i++){

+		delay(100);

+		if(i2crecv(&aux, edid, sizeof(edid), 0) == sizeof(edid))

+			return parseedid128(mode, edid);

+	}

+	return "i2crecv failed to get edid bytes";

 }

 static void

@@ -955,8 +957,7 @@

 	 * get mode information from EDID, this can only be done after the clocks

 	 * are generated by the DPHY and the clock resets have been released.

 	 */

-	err = getmode(&mode);

-	if(err != nil)

+	if((err = getmode(&mode)) != nil)

 		goto out;

 	/* allocates the framebuffer */

-- 

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