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ARM: dts: imx53-qsb: Provide the TVE DAC regulators

PATCH New Fabio Estevam 3 participants 4 messages Jan 3, 2017 – Feb 8, 2017

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Device tree bindings Arm i.MX and Layerscape
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Fabio Estevam

author reviewer
#0 lore raw

PATCH 1/1 ARM: dts: imx53-qsb: Provide the TVE DAC regulators

From: Fabio Estevam <[email protected]>

On imx53-qsb the TVE DAC regulator comes from:

- LDO7 on the board with the Dialog DA9052 PMIC
- VDAC on the board with the MC34708 PMIC

Pass them in the 'dac-supply' node.

While at it, remove the 'regulator-always-on/regulator-boot-on' properties as the TVE driver will properly handle it.

Tested on a imx53-qsb board with a Dialog DA9052 PMIC.

Signed-off-by Fabio Estevam <[email protected]>
---
 arch/arm/boot/dts/imx53-qsb.dts  | 5 ++++-
 arch/arm/boot/dts/imx53-qsrb.dts | 6 ++++--
 2 files changed, 8 insertions(+), 3 deletions(-)
arch/arm/boot/dts/imx53-qsb.dts +4 -1
index 3799396..f4c158c 100644
@@ -90,7 +90,6 @@
 			ldo7_reg: ldo7 {
 				regulator-min-microvolt = <1200000>;
 				regulator-max-microvolt = <3600000>;
-				regulator-always-on;
 			};
 
 			ldo8_reg: ldo8 {

@@ -113,3 +112,7 @@
 		};
 	};
 };
+
+&tve {
+	dac-supply = <&ldo7_reg>;
+};
arch/arm/boot/dts/imx53-qsrb.dts +4 -2
index 96d7eed..479ca4c 100644
@@ -130,8 +130,6 @@
 				regulator-name = "VDAC";
 				regulator-min-microvolt = <2500000>;
 				regulator-max-microvolt = <2775000>;
-				regulator-boot-on;
-				regulator-always-on;
 			};
 
 			vgen1_reg: vgen1 {

@@ -152,3 +150,7 @@
 		};
 	};
 };
+
+&tve {
+	dac-supply = <&vdac_reg>;
+};
Signature · 1 line
2.7.4
Applied
#1 lore raw

PATCH 1/1 ARM: dts: imx53-qsb: Provide the TVE DAC regulators

Quoted 7 lines · Fabio Estevam

From: Fabio Estevam <[email protected]>

On imx53-qsb the TVE DAC regulator comes from:

- LDO7 on the board with the Dialog DA9052 PMIC
- VDAC on the board with the MC34708 PMIC

Quoted 8 lines

Pass them in the 'dac-supply' node.

While at it, remove the 'regulator-always-on/regulator-boot-on' properties as the TVE driver will properly handle it.

Tested on a imx53-qsb board with a Dialog DA9052 PMIC.

Signed-off-by Fabio Estevam <[email protected]>

Applied, thanks.

#2 lore raw

PATCH 1/1 ARM: dts: imx53-qsb: Provide the TVE DAC regulators

In reply to Fabio Estevam
Quoted 25 lines · Fabio Estevam

From: Fabio Estevam <[email protected]>

On imx53-qsb the TVE DAC regulator comes from:

- LDO7 on the board with the Dialog DA9052 PMIC
- VDAC on the board with the MC34708 PMIC

Pass them in the 'dac-supply' node.

While at it, remove the 'regulator-always-on/regulator-boot-on' properties as the TVE driver will properly handle it.

Tested on a imx53-qsb board with a Dialog DA9052 PMIC.

Signed-off-by Fabio Estevam <[email protected]>
---
 arch/arm/boot/dts/imx53-qsb.dts  | 5 ++++-
 arch/arm/boot/dts/imx53-qsrb.dts | 6 ++++--
 2 files changed, 8 insertions(+), 3 deletions(-)
arch/arm/boot/dts/imx53-qsb.dts +0 -0
index 3799396..f4c158c 100644

arch/arm/boot/dts/imx53-qsb.dts line 92

Quoted 3 lines
arch/arm/boot/dts/imx53-qsb.dts +0 -0
@@ -90,7 +90,6 @@
 			ldo7_reg: ldo7 {
 				regulator-min-microvolt = <1200000>;
 				regulator-max-microvolt = <3600000>;

As Lucas pointed out, we could limit the board constraints to the necessary voltage here.
Since this regulator is used as the TVDAC analog power supply, this range should at least be limited to the analog power supply range of the TVDAC, listed in Table 74-9. of the i.MX53 reference manual (2.5-2.75V).

But since the nominal voltage is 2.75V, which was used to determine the analog gain that is supposed to result in the necessary 0.7V peak-to-peak amplitude on the VGA output, I'd say we should just fix the voltage to 2750000 here.

Quoted 17 lines
arch/arm/boot/dts/imx53-qsb.dts +4 -1
-				regulator-always-on;
 			};
 
 			ldo8_reg: ldo8 {

@@ -113,3 +112,7 @@
 		};
 	};
 };
+
+&tve {
+	dac-supply = <&ldo7_reg>;
+};
arch/arm/boot/dts/imx53-qsrb.dts +0 -0
index 96d7eed..479ca4c 100644

arch/arm/boot/dts/imx53-qsrb.dts line 132

Quoted 3 lines
arch/arm/boot/dts/imx53-qsrb.dts +0 -0
@@ -130,8 +130,6 @@
 				regulator-name = "VDAC";
 				regulator-min-microvolt = <2500000>;
 				regulator-max-microvolt = <2775000>;

Same as above.

arch/arm/boot/dts/imx53-qsrb.dts line 156

Quoted 13 lines
arch/arm/boot/dts/imx53-qsrb.dts +4 -2
-				regulator-boot-on;
-				regulator-always-on;
 			};
 
 			vgen1_reg: vgen1 {

@@ -152,3 +150,7 @@
 		};
 	};
 };
+
+&tve {
+	dac-supply = <&vdac_reg>;
+};

regards
Philipp

author reviewer
#3 lore raw

PATCH 1/1 ARM: dts: imx53-qsb: Provide the TVE DAC regulators

Quoted 10 lines · Philipp Zabel

As Lucas pointed out, we could limit the board constraints to the necessary voltage here.
Since this regulator is used as the TVDAC analog power supply, this range should at least be limited to the analog power supply range of the TVDAC, listed in Table 74-9. of the i.MX53 reference manual (2.5-2.75V).

But since the nominal voltage is 2.75V, which was used to determine the analog gain that is supposed to result in the necessary 0.7V peak-to-peak amplitude on the VGA output, I'd say we should just fix the voltage to 2750000 here.

Yes, I will do as suggested. Thanks