Re: [PATCH] ARM: dts: omap5-igep0050: Correct hdmi regulator

From: Peter Ujfalusi
Date: Mon May 09 2016 - 04:26:36 EST


Adding Tomi,

On 05/05/16 21:46, Tony Lindgren wrote:
> * Nishanth Menon <nm@xxxxxx> [160504 11:03]:
>> On 05/04/2016 12:26 PM, Tony Lindgren wrote:
>>> Hi,
>>>
>>> Adding Nishanth to Cc.
>>>
>>> * Peter Ujfalusi <peter.ujfalusi@xxxxxx> [160429 05:15]:
>>>> ldo7_reg, obviously ;)
>>>>
>>>>> status = "okay";
>>>>> regulator-min-microvolt = <1800000>;
>>>>> regulator-max-microvolt = <1800000>;
>>>>> };
>>>
>>> It really seems to be ldo7, otherwise there's no HDMI output. I don't
>>> have the schematics either.
>>>
>>> But it seems we have at least two other regressions in Linux next that
>>> prevent me from testing this properly:
>>>
>>> 1. On igepv5, I get this for the MMC regulator
>>>
>>> ldo9: bypassed regulator has no supply!
>>> ldo9: failed to get the current voltage(-517)
>>> palmas-pmic 48070000.i2c:palmas@48:palmas_pmic: failed to register 48070000.i2c:palmar
>
> The patch I posted fixes this. Then for the HDMI see below.
> I've kept it at 2V like we have in omap5-board-common.dtsi,
> I wonder if it really should be 1.8V though for ldo7 in this
> case?

AFAIK the VDDA for the HDMI needs to be 1.8V along with other VDDAs for DSS
(vdda_dsiporta, vdda_dsiportc and vdda_hdmi).

Tomi: what do you think?

According to the OMAP5 data manual the vdda_hdmi can be in 1.5V or 1.8V mode,
2V is not mentioned in the recommended operating conditions table.

Just to note: on omap5-uevm the ldo7 is connected to VPP1 of OMAP5 (eFuse
power supply), which does require 2V.


> Regards,
>
> Tony
> 8< -----------------
> From: Tony Lindgren <tony@xxxxxxxxxxx>
> Date: Thu, 5 May 2016 11:29:23 -0700
> Subject: [PATCH] ARM: dts: Fix ldo7 source for HDMI on igepv5
>
> Fix ldo7 source for HDMI on igepv5.
>
> Suggested-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
> Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx>
>
> diff --git a/arch/arm/boot/dts/omap5-igep0050.dts b/arch/arm/boot/dts/omap5-igep0050.dts
> index 46ecb1d..72ff6a4 100644
> --- a/arch/arm/boot/dts/omap5-igep0050.dts
> +++ b/arch/arm/boot/dts/omap5-igep0050.dts
> @@ -35,6 +35,12 @@
> };
> };
>
> +&ldo7_reg {
> + status = "okay";
> + regulator-min-microvolt = <2000000>;
> + regulator-max-microvolt = <2000000>;

If we are not changing the default voltage set in the common dtsi file we only
need to status = "okay"

> +};
> +
> &omap5_pmx_core {
> i2c4_pins: pinmux_i2c4_pins {
> pinctrl-single,pins = <
>


--
Péter