Fast mode is the default speed of i2c-designware which can be overridden by platform data or by "clock-frequency" device property. Even though the ACPI 5.1 can pass device properties via _DSD method, shipping systems define the connection speed between I2C host and each slave in their I2cSerialBus resources. Which means speed is not defined per bus but per slave. As there is now support in i2c-core to find the bus speed from ACPI use that to set up the bus speed prior registering the I2C adapter. Signed-off-by: Jarkko Nikula <jarkko.nikula@xxxxxxxxxxxxxxx> --- drivers/i2c/busses/i2c-designware-platdrv.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c index cb846cb50512..0b42a12171f3 100644 --- a/drivers/i2c/busses/i2c-designware-platdrv.c +++ b/drivers/i2c/busses/i2c-designware-platdrv.c @@ -157,7 +157,7 @@ static int dw_i2c_plat_probe(struct platform_device *pdev) struct i2c_adapter *adap; struct resource *mem; int irq, r; - u32 ht = 0; + u32 acpi_speed, ht = 0; irq = platform_get_irq(pdev, 0); if (irq < 0) @@ -192,6 +192,10 @@ static int dw_i2c_plat_probe(struct platform_device *pdev) &dev->clk_freq); } + acpi_speed = i2c_acpi_find_bus_speed(&pdev->dev); + if (acpi_speed) + dev->clk_freq = acpi_speed; + if (has_acpi_companion(&pdev->dev)) dw_i2c_acpi_configure(pdev); -- 2.8.1 -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
