[PATCH] at91sam9g45: fix i2c bus speed
Peter Korsgaard
jacmet at sunsite.dk
Wed Sep 22 05:31:26 EDT 2010
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 at sunsite.dk>
---
arch/arm/mach-at91/at91sam9g45_devices.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/arm/mach-at91/at91sam9g45_devices.c b/arch/arm/mach-at91/at91sam9g45_devices.c
index 5e71ccd..1276bab 100644
--- a/arch/arm/mach-at91/at91sam9g45_devices.c
+++ b/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 = {
--
1.7.1
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