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ARM: 6406/1: at91sam9g45: fix i2c bus speed

Use a correct udelay value to get bus speed around 100KHz. The udelay
value was most likely copied from the older devices, but the 9g45
is signicantly faster (400MHz, DDR, ..), so a udelay of 2 gives a
bus speed of around 190KHz, which is too fast for some devices.
A udelay value of 5 gives a bus speed of around 90KHz here.

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Peter Korsgaard пре 14 година
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1 измењених фајлова са 2 додато и 2 уклоњено
  1. 2 2
      arch/arm/mach-at91/at91sam9g45_devices.c

+ 2 - 2
arch/arm/mach-at91/at91sam9g45_devices.c

@@ -426,7 +426,7 @@ static struct i2c_gpio_platform_data pdata_i2c0 = {
 	.sda_is_open_drain	= 1,
 	.scl_pin		= AT91_PIN_PA21,
 	.scl_is_open_drain	= 1,
-	.udelay			= 2,		/* ~100 kHz */
+	.udelay			= 5,		/* ~100 kHz */
 };
 
 static struct platform_device at91sam9g45_twi0_device = {
@@ -440,7 +440,7 @@ static struct i2c_gpio_platform_data pdata_i2c1 = {
 	.sda_is_open_drain	= 1,
 	.scl_pin		= AT91_PIN_PB11,
 	.scl_is_open_drain	= 1,
-	.udelay			= 2,		/* ~100 kHz */
+	.udelay			= 5,		/* ~100 kHz */
 };
 
 static struct platform_device at91sam9g45_twi1_device = {