# \[PATCH 0/5\] Fix PMI8950 WLED ovp values and more - Subsystems: FRAMEBUFFER LAYER, ARM/QUALCOMM MAILING LIST, ARM/QUALCOMM SUPPORT, BACKLIGHT CLASS/SUBSYSTEM, LED SUBSYSTEM, OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS, THE REST - Maintainers: Helge Deller, Bjorn Andersson, Konrad Dybcio, Lee Jones, Daniel Thompson, Jingoo Han, Pavel Machek, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Linus Torvalds - Series: 5 patches touching 5 files, +60/-7 - Status: SUPERSEDED (Superseded by v2 posted 2026-01-08) - Superseded by v2 (posted 2026-01-08). - Revision v1 (2 revisions archived). - List: linux-fbdev - 12 messages, 3 authors - Page: https://ratatoskr.run/linux-fbdev/2026/01/3356582/t ## \[PATCH 0/5\] Fix PMI8950 WLED ovp values and more - From: Barnabás Czémán \ - Date: 2026-01-07 13:31:14 - Message: https://ratatoskr.run/linux-fbdev/2026/01/3356582.md ```text This patch series fixes supported ovp values related to pmi8950 wled and corrects wled related properties in xiaomi-daisy, xiaomi-land and in xiaomi-vince. Signed-off-by: Barnabás Czémán --- Barnabás Czémán (5): dt-bindings: backlight: qcom-wled: Document ovp values for PMI8950 backlight: qcom-wled: Support ovp values for PMI8950 arm64: dts: qcom: msm8953-xiaomi-vince: correct wled ovp value arm64: dts: qcom: msm8937-xiaomi-land: correct wled ovp value arm64: dts: qcom: msm8953-xiaomi-daisy: fix backlight .../bindings/leds/backlight/qcom-wled.yaml | 20 +++++++++-- arch/arm64/boot/dts/qcom/msm8937-xiaomi-land.dts | 2 +- arch/arm64/boot/dts/qcom/msm8953-xiaomi-daisy.dts | 2 +- arch/arm64/boot/dts/qcom/msm8953-xiaomi-vince.dts | 2 +- drivers/video/backlight/qcom-wled.c | 41 ++++++++++++++++++++-- 5 files changed, 60 insertions(+), 7 deletions(-) --- base-commit: f96074c6d01d8a5e9e2fccd0bba5f2ed654c1f2d change-id: 20260107-pmi8950-wled-b014578f67a6 Best regards, -- Barnabás Czémán [ref] ``` ## \[PATCH 3/5\] arm64: dts: qcom: msm8953-xiaomi-vince: correct wled ovp value - From: Barnabás Czémán \ - Date: 2026-01-07 13:31:19 - Message: https://ratatoskr.run/linux-fbdev/2026/01/3356583.md ```text Correct wled ovp value from 29600 to 29500. Fixes: aa17e707e04a ("arm64: dts: qcom: msm8953: Add device tree for Xiaomi Redmi 5 Plus") Signed-off-by: Barnabás Czémán --- arch/arm64/boot/dts/qcom/msm8953-xiaomi-vince.dts | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/boot/dts/qcom/msm8953-xiaomi-vince.dts b/arch/arm64/boot/dts/qcom/msm8953-xiaomi-vince.dts index d46325e79917..c2a290bf493c 100644 --- a/arch/arm64/boot/dts/qcom/msm8953-xiaomi-vince.dts +++ b/arch/arm64/boot/dts/qcom/msm8953-xiaomi-vince.dts @@ -169,7 +169,7 @@ &pm8953_resin { &pmi8950_wled { qcom,current-limit-microamp = <20000>; - qcom,ovp-millivolt = <29600>; + qcom,ovp-millivolt = <29500>; qcom,num-strings = <2>; qcom,external-pfet; qcom,cabc; -- 2.52.0 ``` ## \[PATCH 5/5\] arm64: dts: qcom: msm8953-xiaomi-daisy: fix backlight - From: Barnabás Czémán \ - Date: 2026-01-07 13:31:30 - Message: https://ratatoskr.run/linux-fbdev/2026/01/3356584.md ```text Set qcom,num-strings to 3 instead of 2 for avoid stripes. Fixes: 38d779c26395 ("arm64: dts: qcom: msm8953: Add device tree for Xiaomi Mi A2 Lite") Signed-off-by: Barnabás Czémán --- arch/arm64/boot/dts/qcom/msm8953-xiaomi-daisy.dts | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/boot/dts/qcom/msm8953-xiaomi-daisy.dts b/arch/arm64/boot/dts/qcom/msm8953-xiaomi-daisy.dts index ddd7af616794..59f873a06e4d 100644 --- a/arch/arm64/boot/dts/qcom/msm8953-xiaomi-daisy.dts +++ b/arch/arm64/boot/dts/qcom/msm8953-xiaomi-daisy.dts @@ -157,7 +157,7 @@ &pm8953_resin { &pmi8950_wled { qcom,current-limit-microamp = <20000>; - qcom,num-strings = <2>; + qcom,num-strings = <3>; status = "okay"; }; -- 2.52.0 ``` ## \[PATCH 2/5\] backlight: qcom-wled: Support ovp values for PMI8950 - From: Barnabás Czémán \ - Date: 2026-01-07 13:31:30 - Message: https://ratatoskr.run/linux-fbdev/2026/01/3356585.md ```text WLED4 found in PMI8950 supports different ovp values. Fixes: 10258bf4534bf ("backlight: qcom-wled: Add PMI8950 compatible") Signed-off-by: Barnabás Czémán --- drivers/video/backlight/qcom-wled.c | 41 +++++++++++++++++++++++++++++++++++-- 1 file changed, 39 insertions(+), 2 deletions(-) diff --git a/drivers/video/backlight/qcom-wled.c b/drivers/video/backlight/qcom-wled.c index a63bb42c8f8b..91335aeb65a3 100644 --- a/drivers/video/backlight/qcom-wled.c +++ b/drivers/video/backlight/qcom-wled.c @@ -1244,6 +1244,15 @@ static const struct wled_var_cfg wled4_ovp_cfg = { .size = ARRAY_SIZE(wled4_ovp_values), }; +static const u32 pmi8950_wled4_ovp_values[] = { + 31000, 29500, 19400, 17800, +}; + +static const struct wled_var_cfg pmi8950_wled4_ovp_cfg = { + .values = pmi8950_wled4_ovp_values, + .size = ARRAY_SIZE(pmi8950_wled4_ovp_values), +}; + static inline u32 wled5_ovp_values_fn(u32 idx) { /* @@ -1357,6 +1366,29 @@ static int wled_configure(struct wled *wled) }, }; + const struct wled_u32_opts pmi8950_wled4_opts[] = { + { + .name = "qcom,current-boost-limit", + .val_ptr = &cfg->boost_i_limit, + .cfg = &wled4_boost_i_limit_cfg, + }, + { + .name = "qcom,current-limit-microamp", + .val_ptr = &cfg->string_i_limit, + .cfg = &wled4_string_i_limit_cfg, + }, + { + .name = "qcom,ovp-millivolt", + .val_ptr = &cfg->ovp, + .cfg = &pmi8950_wled4_ovp_cfg, + }, + { + .name = "qcom,switching-freq", + .val_ptr = &cfg->switch_freq, + .cfg = &wled3_switch_freq_cfg, + }, + }; + const struct wled_u32_opts wled5_opts[] = { { .name = "qcom,current-boost-limit", @@ -1423,8 +1455,13 @@ static int wled_configure(struct wled *wled) break; case 4: - u32_opts = wled4_opts; - size = ARRAY_SIZE(wled4_opts); + if (of_device_is_compatible(dev->of_node, "qcom,pmi8950-wled")) { + u32_opts = pmi8950_wled4_opts; + size = ARRAY_SIZE(pmi8950_wled4_opts); + } else { + u32_opts = wled4_opts; + size = ARRAY_SIZE(wled4_opts); + } *cfg = wled4_config_defaults; wled->wled_set_brightness = wled4_set_brightness; wled->wled_sync_toggle = wled3_sync_toggle; -- 2.52.0 ``` ## \[PATCH 1/5\] dt-bindings: backlight: qcom-wled: Document ovp values for PMI8950 - From: Barnabás Czémán \ - Date: 2026-01-07 13:33:36 - Message: https://ratatoskr.run/linux-fbdev/2026/01/3356587.md ```text Document ovp values supported by wled found in PMI8950. Signed-off-by: Barnabás Czémán --- .../bindings/leds/backlight/qcom-wled.yaml | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) diff --git a/Documentation/devicetree/bindings/leds/backlight/qcom-wled.yaml b/Documentation/devicetree/bindings/leds/backlight/qcom-wled.yaml index a8490781011d..306fb6642617 100644 --- a/Documentation/devicetree/bindings/leds/backlight/qcom-wled.yaml +++ b/Documentation/devicetree/bindings/leds/backlight/qcom-wled.yaml @@ -98,8 +98,6 @@ properties: description: | Over-voltage protection limit. This property is for WLED4 only. $ref: /schemas/types.yaml#/definitions/uint32 - enum: [ 18100, 19600, 29600, 31100 ] - default: 29600 qcom,num-strings: description: | @@ -239,6 +237,24 @@ allOf: minimum: 0 maximum: 4095 + - if: + properties: + compatible: + contains: + const: qcom,pmi8950-wled + + then: + properties: + qcom,ovp-millivolt: + enum: [ 17800, 19400, 29500, 31000 ] + default: 29500 + + else: + properties: + qcom,ovp-millivolt: + enum: [ 18100, 19600, 29600, 31100 ] + default: 29600 + required: - compatible - reg -- 2.52.0 ``` ## \[PATCH 4/5\] arm64: dts: qcom: msm8937-xiaomi-land: correct wled ovp value - From: Barnabás Czémán \ - Date: 2026-01-07 13:33:48 - Message: https://ratatoskr.run/linux-fbdev/2026/01/3356588.md ```text Correct wled ovp value from 29600 to 29500. Fixes: 2144f6d57d8e ("arm64: dts: qcom: Add Xiaomi Redmi 3S") Signed-off-by: Barnabás Czémán --- arch/arm64/boot/dts/qcom/msm8937-xiaomi-land.dts | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/boot/dts/qcom/msm8937-xiaomi-land.dts b/arch/arm64/boot/dts/qcom/msm8937-xiaomi-land.dts index 91837ff940f1..4f301e7c6517 100644 --- a/arch/arm64/boot/dts/qcom/msm8937-xiaomi-land.dts +++ b/arch/arm64/boot/dts/qcom/msm8937-xiaomi-land.dts @@ -178,7 +178,7 @@ &pmi8950_wled { qcom,num-strings = <2>; qcom,external-pfet; qcom,current-limit-microamp = <20000>; - qcom,ovp-millivolt = <29600>; + qcom,ovp-millivolt = <29500>; status = "okay"; }; -- 2.52.0 ``` ## Re: \[PATCH 1/5\] dt-bindings: backlight: qcom-wled: Document ovp values for PMI8950 - From: Konrad Dybcio \ - Date: 2026-01-07 14:03:46 - Message: https://ratatoskr.run/linux-fbdev/2026/01/3356631.md ```text On 1/7/26 2:31 PM, Barnabás Czémán wrote: > Document ovp values supported by wled found in PMI8950. > > Signed-off-by: Barnabás Czémán > --- > .../bindings/leds/backlight/qcom-wled.yaml | 20 ++++++++++++++++++-- > 1 file changed, 18 insertions(+), 2 deletions(-) > > diff --git a/Documentation/devicetree/bindings/leds/backlight/qcom-wled.yaml b/Documentation/devicetree/bindings/leds/backlight/qcom-wled.yaml > index a8490781011d..306fb6642617 100644 > --- a/Documentation/devicetree/bindings/leds/backlight/qcom-wled.yaml > +++ b/Documentation/devicetree/bindings/leds/backlight/qcom-wled.yaml > @@ -98,8 +98,6 @@ properties: > description: | > Over-voltage protection limit. This property is for WLED4 only. > $ref: /schemas/types.yaml#/definitions/uint32 > - enum: [ 18100, 19600, 29600, 31100 ] > - default: 29600 > > qcom,num-strings: > description: | > @@ -239,6 +237,24 @@ allOf: > minimum: 0 > maximum: 4095 > > + - if: > + properties: > + compatible: > + contains: > + const: qcom,pmi8950-wled > + > + then: > + properties: > + qcom,ovp-millivolt: > + enum: [ 17800, 19400, 29500, 31000 ] > + default: 29500 > + > + else: > + properties: > + qcom,ovp-millivolt: > + enum: [ 18100, 19600, 29600, 31100 ] > + default: 29600 Out of the supported ones: { .compatible = "qcom,pmi8950-wled", .data = (void *)4 }, { .compatible = "qcom,pmi8994-wled", .data = (void *)4 }, { .compatible = "qcom,pmi8998-wled", .data = (void *)4 }, { .compatible = "qcom,pm660l-wled", .data = (void *)4 }, I can confirm both allowed and default values for PMI8950/98/PM660L I could not find any data for PMI8994 (or PMI8996, the essentially PMI8994-revbump), but it's very probable that 8950 is an oddball, so: Reviewed-by: Konrad Dybcio Konrad ``` ## Re: \[PATCH 2/5\] backlight: qcom-wled: Support ovp values for PMI8950 - From: Konrad Dybcio \ - Date: 2026-01-07 14:05:41 - Message: https://ratatoskr.run/linux-fbdev/2026/01/3356633.md ```text On 1/7/26 2:31 PM, Barnabás Czémán wrote: > WLED4 found in PMI8950 supports different ovp values. > > Fixes: 10258bf4534bf ("backlight: qcom-wled: Add PMI8950 compatible") > Signed-off-by: Barnabás Czémán > --- [...] > case 4: > - u32_opts = wled4_opts; > - size = ARRAY_SIZE(wled4_opts); > + if (of_device_is_compatible(dev->of_node, "qcom,pmi8950-wled")) { > + u32_opts = pmi8950_wled4_opts; > + size = ARRAY_SIZE(pmi8950_wled4_opts); > + } else { > + u32_opts = wled4_opts; > + size = ARRAY_SIZE(wled4_opts); > + } I really don't like how this driver went about abstracting parsing all of that, but that's not your fault Reviewed-by: Konrad Dybcio Konrad ``` ## Re: \[PATCH 3/5\] arm64: dts: qcom: msm8953-xiaomi-vince: correct wled ovp value - From: Konrad Dybcio \ - Date: 2026-01-07 14:08:10 - Message: https://ratatoskr.run/linux-fbdev/2026/01/3356638.md ```text On 1/7/26 2:31 PM, Barnabás Czémán wrote: > Correct wled ovp value from 29600 to 29500. This tells us what the fix is, but not why the fix needs to be made. We can infer the former from the patch contents, but it's really important that the next reader, perhaps in 5 years, can find out the reason it was made. How about: """ PMI8950 doesn't actually support setting an OVP threshold value of 29.6 V. The closest allowed value is 29.5 V. Set that instead. """ With this or similar commit message: Reviewed-by: Konrad Dybcio Konrad ``` ## Re: \[PATCH 1/5\] dt-bindings: backlight: qcom-wled: Document ovp values for PMI8950 - From: Krzysztof Kozlowski \ - Date: 2026-01-07 14:12:02 - Message: https://ratatoskr.run/linux-fbdev/2026/01/3356651.md ```text On 07/01/2026 14:31, Barnabás Czémán wrote: > Document ovp values supported by wled found in PMI8950. > > Signed-off-by: Barnabás Czémán > --- > .../bindings/leds/backlight/qcom-wled.yaml | 20 ++++++++++++++++++-- > 1 file changed, 18 insertions(+), 2 deletions(-) > > diff --git a/Documentation/devicetree/bindings/leds/backlight/qcom-wled.yaml b/Documentation/devicetree/bindings/leds/backlight/qcom-wled.yaml > index a8490781011d..306fb6642617 100644 > --- a/Documentation/devicetree/bindings/leds/backlight/qcom-wled.yaml > +++ b/Documentation/devicetree/bindings/leds/backlight/qcom-wled.yaml > @@ -98,8 +98,6 @@ properties: > description: | > Over-voltage protection limit. This property is for WLED4 only. > $ref: /schemas/types.yaml#/definitions/uint32 > - enum: [ 18100, 19600, 29600, 31100 ] minimum and maximum should stay here. Or alternatively enum with all the values, but I think first options is enough. Best regards, Krzysztof ``` ## Re: \[PATCH 5/5\] arm64: dts: qcom: msm8953-xiaomi-daisy: fix backlight - From: Konrad Dybcio \ - Date: 2026-01-07 14:13:14 - Message: https://ratatoskr.run/linux-fbdev/2026/01/3356652.md ```text On 1/7/26 2:31 PM, Barnabás Czémán wrote: > Set qcom,num-strings to 3 instead of 2 for avoid stripes. """ The backlight on this device is connected via 3 strings. Currently, the DT claims only two are present, which results in visible stripes on the display (since every third backlight string remains unconfigured). Fix the number of strings to avoid that """ Konrad > > Fixes: 38d779c26395 ("arm64: dts: qcom: msm8953: Add device tree for Xiaomi Mi A2 Lite") > Signed-off-by: Barnabás Czémán > --- > arch/arm64/boot/dts/qcom/msm8953-xiaomi-daisy.dts | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/arm64/boot/dts/qcom/msm8953-xiaomi-daisy.dts b/arch/arm64/boot/dts/qcom/msm8953-xiaomi-daisy.dts > index ddd7af616794..59f873a06e4d 100644 > --- a/arch/arm64/boot/dts/qcom/msm8953-xiaomi-daisy.dts > +++ b/arch/arm64/boot/dts/qcom/msm8953-xiaomi-daisy.dts > @@ -157,7 +157,7 @@ &pm8953_resin { > > &pmi8950_wled { > qcom,current-limit-microamp = <20000>; > - qcom,num-strings = <2>; > + qcom,num-strings = <3>; > > status = "okay"; > }; > ``` ## Re: \[PATCH 1/5\] dt-bindings: backlight: qcom-wled: Document ovp values for PMI8950 - From: \ - Date: 2026-01-08 02:45:16 - Message: https://ratatoskr.run/linux-fbdev/2026/01/3357553.md ```text On 2026-01-07 15:03, Konrad Dybcio wrote: > On 1/7/26 2:31 PM, Barnabás Czémán wrote: >> Document ovp values supported by wled found in PMI8950. >> >> Signed-off-by: Barnabás Czémán >> --- >> .../bindings/leds/backlight/qcom-wled.yaml | 20 ++++++++++++++++++-- >> 1 file changed, 18 insertions(+), 2 deletions(-) >> >> diff --git a/Documentation/devicetree/bindings/leds/backlight/qcom-wled.yaml b/Documentation/devicetree/bindings/leds/backlight/qcom-wled.yaml >> index a8490781011d..306fb6642617 100644 >> --- a/Documentation/devicetree/bindings/leds/backlight/qcom-wled.yaml >> +++ b/Documentation/devicetree/bindings/leds/backlight/qcom-wled.yaml >> @@ -98,8 +98,6 @@ properties: >> description: | >> Over-voltage protection limit. This property is for WLED4 only. >> $ref: /schemas/types.yaml#/definitions/uint32 >> - enum: [ 18100, 19600, 29600, 31100 ] >> - default: 29600 >> >> qcom,num-strings: >> description: | >> @@ -239,6 +237,24 @@ allOf: >> minimum: 0 >> maximum: 4095 >> >> + - if: >> + properties: >> + compatible: >> + contains: >> + const: qcom,pmi8950-wled >> + >> + then: >> + properties: >> + qcom,ovp-millivolt: >> + enum: [ 17800, 19400, 29500, 31000 ] >> + default: 29500 >> + >> + else: >> + properties: >> + qcom,ovp-millivolt: >> + enum: [ 18100, 19600, 29600, 31100 ] >> + default: 29600 > > Out of the supported ones: > > { .compatible = "qcom,pmi8950-wled", .data = (void *)4 }, > { .compatible = "qcom,pmi8994-wled", .data = (void *)4 }, > { .compatible = "qcom,pmi8998-wled", .data = (void *)4 }, > { .compatible = "qcom,pm660l-wled", .data = (void *)4 }, > > I can confirm both allowed and default values for PMI8950/98/PM660L > > I could not find any data for PMI8994 (or PMI8996, the essentially > PMI8994-revbump), but it's very probable that 8950 is an oddball, This commits add support for pmi8998 and documentation is telling which PMIC supports which values: https://git.codelinaro.org/clo/la/kernel/msm-4.4/-/commit/7a1b6d0276828f270180db40935bb034a3470865 TLDR: - qcom,ovp-mv : Over voltage protection threshold in mV. Default is 29500. Supported values are: - 31000, 29500, 19400, 17800 for pmi8994/8952/8996. (As far as i know 8952=8950) - 31100, 29600, 19600, 18100 for pmicobalt/pm2falcon (pmi8998/pm660l) > so: > > Reviewed-by: Konrad Dybcio > > Konrad ```