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charset=us-ascii Content-Disposition: inline In-Reply-To: <75d22f54-eb55-4e55-9582-5b407f41ee81@quicinc.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260409_063554_572444_FBF1F28C X-CRM114-Status: GOOD ( 28.75 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, Apr 09, 2026 at 11:14:10AM +0530, Ayushi Makhija wrote: > On 3/26/2026 9:28 PM, Bjorn Andersson wrote: > > On Thu, Mar 26, 2026 at 03:06:52PM +0530, Ayushi Makhija wrote: > >> On 3/24/2026 7:34 AM, Bjorn Andersson wrote: > >>> On Mon, Mar 23, 2026 at 03:52:29PM +0530, Ayushi Makhija wrote: > >>>> The NT37801 Sepc V1.0 chapter "5.7.1 Power On Sequence" states > >>>> VDDI=1.65V~1.95V, so set sufficient voltage for panel nt37801. > >>>> > >>> > >>> Please add Fixes: tag. > >>> > >> > >> Hi Bjorn, > >> > >> Sure, will add in new patchset. > >> > >>>> Signed-off-by: Ayushi Makhija > >>> > >>> Please start using your oss.qualcomm.com address. > >>> > >>>> --- > >>>> arch/arm64/boot/dts/qcom/sm8750-mtp.dts | 2 +- > >>>> 1 file changed, 1 insertion(+), 1 deletion(-) > >>>> > >>>> diff --git a/arch/arm64/boot/dts/qcom/sm8750-mtp.dts b/arch/arm64/boot/dts/qcom/sm8750-mtp.dts > >>>> index 3837f6785320..6ba4e69bf377 100644 > >>>> --- a/arch/arm64/boot/dts/qcom/sm8750-mtp.dts > >>>> +++ b/arch/arm64/boot/dts/qcom/sm8750-mtp.dts > >>>> @@ -462,7 +462,7 @@ vreg_l11b_1p0: ldo11 { > >>>> > >>>> vreg_l12b_1p8: ldo12 { > >>>> regulator-name = "vreg_l12b_1p8"; > >>>> - regulator-min-microvolt = <1200000>; > >>>> + regulator-min-microvolt = <1650000>; > >>> > >>> Are you sure it's not supposed to be 1.8V, given the name of the rail? > >>> > >>> Regards, > >>> Bjorn > >> > >> There was already discussion regarding the minimum voltage for this regulator on sm8550 target > >> on other upstream patch. > >> > >> Link: https://lore.kernel.org/all/aQQdQoCLeKhYtY7W@yuanjiey.ap.qualcomm.com/ > >> > >> This values is according to the NT37801 panel sec > >> "The NT37801 Sepc V1.0 chapter "5.7.1 Power On Sequence" states > >> VDDI=1.65V~1.95V." > >> > > > > Yes, so the panel requires 1.65V, so regulator-min-microvolt needs to be > > at least that. But regulator-min-microvolt should account for all the > > consumers of the rail, are there any others? > > > > Which leads me to my question, the people designing the board named the > > rail VREG_L12B_1P8 in the schematics, why didn't they name it > > VREG_L12B_1P65? > > > > Please check all the consumers and make the regulator-min-microvolt work > > for all of them - if that's 1.65V, then your change is good. > > > > Regards, > > Bjorn > > Hi Bjorn, > > There is only one consumer of VREG_L12B_1P8 rail, i.e. NT37801 panel. > So regulator-min-microvolt as 1.65V should be fine for VREG_L12B_1P8 rail. > Had to look it up myself. MTP power grid says it should be 1.8V. Thank you, Bjorn > Thanks, > Ayushi >