[PATCH v2] arm64: dts: qcom: shikra-iqs-som: Correct PM8150 L10 voltage range

[PATCH v2] arm64: dts: qcom: shikra-iqs-som: Correct PM8150 L10 voltage range

[Rakesh Kota]

On Shikra IQS, the L10 rail supplies the SD card's VMMC. Its maximum
voltage must be limited to 3.3 V because the derived VQMMC voltage on
L2 supports up to approximately 3.3 V. Allowing VMMC to reach 3.544 V
can drive VQMMC beyond its supported range, potentially causing SD
bus bit errors and resulting in the voltage negotiation failure:

l2: unsupportable voltage range: 3500000-3296000uV

Reducing L10's maximum voltage to 3.3 V keeps both rails within their
supported operating ranges.

Co-developed-by: Nitin Rawat <nitin.rawat@oss.qualcomm.com>
Signed-off-by: Nitin Rawat <nitin.rawat@oss.qualcomm.com>
Signed-off-by: Rakesh Kota <rakesh.kota@oss.qualcomm.com>
---
Changes in v2:
- Update the commit message.
- Link to v1: https://patch.msgid.link/20260922-fix_l10_max-v1-1-d0c99f063bf4@oss.qualcomm.com
---
 arch/arm64/boot/dts/qcom/shikra-iqs-som.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/qcom/shikra-iqs-som.dtsi b/arch/arm64/boot/dts/qcom/shikra-iqs-som.dtsi
index e119ace54e58..ba8c93f01546 100644
--- a/arch/arm64/boot/dts/qcom/shikra-iqs-som.dtsi
+++ b/arch/arm64/boot/dts/qcom/shikra-iqs-som.dtsi
@@ -172,7 +172,7 @@ pm8150_l9: l9 {
 
 		pm8150_l10: l10 {
 			regulator-min-microvolt = <2700000>;
-			regulator-max-microvolt = <3544000>;
+			regulator-max-microvolt = <3300000>;
 		};
 
 		pm8150_l11: l11 {

---
base-commit: 6375e61c01e93e35ee7acd336a689ac1fae4b509
change-id: 20260922-fix_l10_max-c7390de98d73

Best regards,
--  
Rakesh Kota <rakesh.kota@oss.qualcomm.com>

Re: [PATCH v2] arm64: dts: qcom: shikra-iqs-som: Correct PM8150 L10 voltage range

[Abel Vesa]

On 26-09-29 14:05:18, Rakesh Kota wrote:
> On Shikra IQS, the L10 rail supplies the SD card's VMMC. Its maximum
> voltage must be limited to 3.3 V because the derived VQMMC voltage on
> L2 supports up to approximately 3.3 V. Allowing VMMC to reach 3.544 V
> can drive VQMMC beyond its supported range, potentially causing SD
> bus bit errors and resulting in the voltage negotiation failure:
> 
> l2: unsupportable voltage range: 3500000-3296000uV
> 
> Reducing L10's maximum voltage to 3.3 V keeps both rails within their
> supported operating ranges.
> 
> Co-developed-by: Nitin Rawat <nitin.rawat@oss.qualcomm.com>
> Signed-off-by: Nitin Rawat <nitin.rawat@oss.qualcomm.com>
> Signed-off-by: Rakesh Kota <rakesh.kota@oss.qualcomm.com>

No fixes tag?

The rest looks good to me, so:

Reviewed-by: Abel Vesa <abel.vesa@oss.qualcomm.com>

Re: [PATCH v2] arm64: dts: qcom: shikra-iqs-som: Correct PM8150 L10 voltage range

[Konrad Dybcio]

On 9/29/26 10:35 AM, Rakesh Kota wrote:
> On Shikra IQS, the L10 rail supplies the SD card's VMMC. Its maximum
> voltage must be limited to 3.3 V because the derived VQMMC voltage on
> L2 supports up to approximately 3.3 V. Allowing VMMC to reach 3.544 V
> can drive VQMMC beyond its supported range, potentially causing SD
> bus bit errors and resulting in the voltage negotiation failure:
> 
> l2: unsupportable voltage range: 3500000-3296000uV
> 
> Reducing L10's maximum voltage to 3.3 V keeps both rails within their
> supported operating ranges.
> 
> Co-developed-by: Nitin Rawat <nitin.rawat@oss.qualcomm.com>
> Signed-off-by: Nitin Rawat <nitin.rawat@oss.qualcomm.com>
> Signed-off-by: Rakesh Kota <rakesh.kota@oss.qualcomm.com>
> ---

Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>

Konrad