On Tue, Jun 27, 2017 at 10:54 PM, Fabio Estevam festevam@gmail.com wrote:
Hi Gautam,
On Wed, Jun 21, 2017 at 1:18 PM, Gautam Bhat mindentropy@gmail.com wrote:
This change sets the VLDO4 settings output to 2.8V in PMIC initialization so that the MIPI DSI and MIPI CSI input voltage is 2.8V as per the schematics.
As we do not have MIPI DSI / MIPI CSI support in U-Boot, it is preferable to let the kernel configure the regulator.
You can do this is the device tree like this:
diff --git a/arch/arm/boot/dts/imx7d-sdb.dts b/arch/arm/boot/dts/imx7d-sdb.dts index 54c4540..923aa755 100644 --- a/arch/arm/boot/dts/imx7d-sdb.dts +++ b/arch/arm/boot/dts/imx7d-sdb.dts @@ -285,8 +285,8 @@ };
vgen6_reg: vldo4 {
regulator-min-microvolt = <1800000>;regulator-max-microvolt = <3300000>;
regulator-min-microvolt = <2800000>;regulator-max-microvolt = <2800000>; regulator-always-on; }; };Regards,
Fabio Estevam
Hi Fabio,
The patch for the kernel was supposed to be next. Should I send the kernel patch to mainline or some place else?
Coming to u-boot, the fact that even if there is no MIPI DSI/MIPI CSI support the voltage would still be 3.3V in those rails. In my case I do not attach the display after u-boot boots up. I keep the display attached and sometimes I leave it in u-boot command line without going over to the kernel. Since this is a development board this is often the case for many developers and there may be chances of the display getting damaged.
Thanks, Gautam.