[PATCH 0/4] regulator: add support for the STM32 ADC booster

[PATCH 0/4] regulator: add support for the STM32 ADC booster

[Fabrice Gasnier]

Add support for the 3.3V booster regulator embedded in stm32h7 and stm32mp1
devices, that can be used to supply ADC analog input switches.
It's useful to reach full ADC performance when their supply is below 2.7V
(vdda by default).

Fabrice Gasnier (4):
  dt-bindings: regulator: add support for the stm32-booster
  regulator: add support for the stm32-booster
  ARM: multi_v7_defconfig: enable STM32 booster regulator
  ARM: dts: stm32: add booster for ADC analog switches on stm32mp157c

 .../bindings/regulator/st,stm32-booster.txt        |  18 +++
 arch/arm/boot/dts/stm32mp157c.dtsi                 |   6 +
 arch/arm/configs/multi_v7_defconfig                |   1 +
 drivers/regulator/Kconfig                          |  11 ++
 drivers/regulator/Makefile                         |   1 +
 drivers/regulator/stm32-booster.c                  | 132 +++++++++++++++++++++
 6 files changed, 169 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/regulator/st,stm32-booster.txt
 create mode 100644 drivers/regulator/stm32-booster.c

-- 
2.7.4

[PATCH 1/4] dt-bindings: regulator: add support for the stm32-booster

[Fabrice Gasnier]

Document the 3.3V booster regulator embedded in stm32h7 and stm32mp1
devices, that can be used to supply ADC analog input switches.
It's controlled by using system configuration registers (SYSCFG).
Introduce two compatibles as the booster regulator is controlled by:
- a unique register/bit in STM32H7
- a set/clear register pair in STM32MP1

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
---
 .../devicetree/bindings/regulator/st,stm32-booster.txt | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/regulator/st,stm32-booster.txt

diff --git a/Documentation/devicetree/bindings/regulator/st,stm32-booster.txt b/Documentation/devicetree/bindings/regulator/st,stm32-booster.txt
new file mode 100644
index 0000000..479ad4c
--- /dev/null
+++ b/Documentation/devicetree/bindings/regulator/st,stm32-booster.txt
@@ -0,0 +1,18 @@
+STM32 BOOSTER - Booster for ADC analog input switches
+
+Some STM32 devices embed a 3.3V booster supplied by Vdda, that can be used
+to supply ADC analog input switches.
+
+Required properties:
+- compatible: Should be one of:
+  "st,stm32h7-booster"
+  "st,stm32mp1-booster"
+- st,syscfg: Phandle to system configuration controller.
+- vdda-supply: Phandle to the vdda input analog voltage.
+
+Example:
+	booster: regulator-booster {
+		compatible = "st,stm32mp1-booster";
+		st,syscfg = <&syscfg>;
+		vdda-supply = <&vdda>;
+	};
-- 
2.7.4

[PATCH 2/4] regulator: add support for the stm32-booster

[Fabrice Gasnier]

Add support for the 3.3V booster regulator embedded in stm32h7 and stm32mp1
devices, that can be used to supply ADC analog input switches.

This regulator is supplied by vdda. It's controlled by using SYSCFG:
- STM32H7 has a unique register to set/clear the booster enable bit
- STM32MP1 has separate set and clear registers to configure it.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
---
 drivers/regulator/Kconfig         |  11 ++++
 drivers/regulator/Makefile        |   1 +
 drivers/regulator/stm32-booster.c | 132 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 144 insertions(+)
 create mode 100644 drivers/regulator/stm32-booster.c

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 6c37f0d..b34f45d 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -828,6 +828,17 @@ config REGULATOR_SKY81452
 	  This driver can also be built as a module. If so, the module
 	  will be called sky81452-regulator.
 
+config REGULATOR_STM32_BOOSTER
+	tristate "STMicroelectronics STM32 BOOSTER"
+	depends on ARCH_STM32 || COMPILE_TEST
+	help
+	  This driver supports internal booster (3V3) embedded in some
+	  STMicroelectronics STM32 chips. It can be used to supply ADC analog
+	  input switches when vdda supply is below 2.7V.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called stm32-booster.
+
 config REGULATOR_STM32_VREFBUF
 	tristate "STMicroelectronics STM32 VREFBUF"
 	depends on ARCH_STM32 || COMPILE_TEST
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index 93f5384..34a7b47 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -104,6 +104,7 @@ obj-$(CONFIG_REGULATOR_S2MPS11) += s2mps11.o
 obj-$(CONFIG_REGULATOR_S5M8767) += s5m8767.o
 obj-$(CONFIG_REGULATOR_SC2731) += sc2731-regulator.o
 obj-$(CONFIG_REGULATOR_SKY81452) += sky81452-regulator.o
+obj-$(CONFIG_REGULATOR_STM32_BOOSTER) += stm32-booster.o
 obj-$(CONFIG_REGULATOR_STM32_VREFBUF) += stm32-vrefbuf.o
 obj-$(CONFIG_REGULATOR_STM32_PWR) += stm32-pwr.o
 obj-$(CONFIG_REGULATOR_STPMIC1) += stpmic1_regulator.o
diff --git a/drivers/regulator/stm32-booster.c b/drivers/regulator/stm32-booster.c
new file mode 100644
index 0000000..2a89766
--- /dev/null
+++ b/drivers/regulator/stm32-booster.c
@@ -0,0 +1,132 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) STMicroelectronics 2019
+// Author(s): Fabrice Gasnier <fabrice.gasnier@st.com>.
+
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/of_regulator.h>
+
+/* STM32H7 SYSCFG register */
+#define STM32H7_SYSCFG_PMCR		0x04
+#define STM32H7_SYSCFG_BOOSTE_MASK	BIT(8)
+
+/* STM32MP1 SYSCFG has set and clear registers */
+#define STM32MP1_SYSCFG_PMCSETR		0x04
+#define STM32MP1_SYSCFG_PMCCLRR		0x44
+#define STM32MP1_SYSCFG_EN_BOOSTER_MASK	BIT(8)
+
+static const struct regulator_ops stm32h7_booster_ops = {
+	.list_voltage	= regulator_list_voltage_linear,
+	.enable		= regulator_enable_regmap,
+	.disable	= regulator_disable_regmap,
+	.is_enabled	= regulator_is_enabled_regmap,
+};
+
+static const struct regulator_desc stm32h7_booster_desc = {
+	.name = "booster",
+	.supply_name = "vdda",
+	.n_voltages = 1,
+	.type = REGULATOR_VOLTAGE,
+	.min_uV = 3300000,
+	.fixed_uV = 3300000,
+	.ramp_delay = 66000, /* up to 50us to stabilize */
+	.ops = &stm32h7_booster_ops,
+	.enable_reg = STM32H7_SYSCFG_PMCR,
+	.enable_mask = STM32H7_SYSCFG_BOOSTE_MASK,
+	.owner = THIS_MODULE,
+};
+
+static int stm32mp1_booster_enable(struct regulator_dev *rdev)
+{
+	return regmap_write(rdev->regmap, STM32MP1_SYSCFG_PMCSETR,
+			    STM32MP1_SYSCFG_EN_BOOSTER_MASK);
+}
+
+static int stm32mp1_booster_disable(struct regulator_dev *rdev)
+{
+	return regmap_write(rdev->regmap, STM32MP1_SYSCFG_PMCCLRR,
+			    STM32MP1_SYSCFG_EN_BOOSTER_MASK);
+}
+
+static const struct regulator_ops stm32mp1_booster_ops = {
+	.list_voltage	= regulator_list_voltage_linear,
+	.enable		= stm32mp1_booster_enable,
+	.disable	= stm32mp1_booster_disable,
+	.is_enabled	= regulator_is_enabled_regmap,
+};
+
+static const struct regulator_desc stm32mp1_booster_desc = {
+	.name = "booster",
+	.supply_name = "vdda",
+	.n_voltages = 1,
+	.type = REGULATOR_VOLTAGE,
+	.min_uV = 3300000,
+	.fixed_uV = 3300000,
+	.ramp_delay = 66000,
+	.ops = &stm32mp1_booster_ops,
+	.enable_reg = STM32MP1_SYSCFG_PMCSETR,
+	.enable_mask = STM32MP1_SYSCFG_EN_BOOSTER_MASK,
+	.owner = THIS_MODULE,
+};
+
+static int stm32_booster_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = pdev->dev.of_node;
+	struct regulator_config config = { };
+	const struct regulator_desc *desc;
+	struct regulator_dev *rdev;
+	struct regmap *regmap;
+	int ret;
+
+	regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
+	if (IS_ERR(regmap))
+		return PTR_ERR(regmap);
+
+	desc = (const struct regulator_desc *)
+		of_match_device(dev->driver->of_match_table, dev)->data;
+
+	config.regmap = regmap;
+	config.dev = dev;
+	config.of_node = np;
+	config.init_data = of_get_regulator_init_data(dev, np, desc);
+
+	rdev = devm_regulator_register(dev, desc, &config);
+	if (IS_ERR(rdev)) {
+		ret = PTR_ERR(rdev);
+		dev_err(dev, "register failed with error %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct of_device_id stm32_booster_of_match[] = {
+	{
+		.compatible = "st,stm32h7-booster",
+		.data = (void *)&stm32h7_booster_desc
+	}, {
+		.compatible = "st,stm32mp1-booster",
+		.data = (void *)&stm32mp1_booster_desc
+	}, {
+	},
+};
+MODULE_DEVICE_TABLE(of, stm32_booster_of_match);
+
+static struct platform_driver stm32_booster_driver = {
+	.probe = stm32_booster_probe,
+	.driver = {
+		.name  = "stm32-booster",
+		.of_match_table = of_match_ptr(stm32_booster_of_match),
+	},
+};
+module_platform_driver(stm32_booster_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics STM32 booster regulator driver");
+MODULE_ALIAS("platform:stm32-booster");
-- 
2.7.4

[PATCH 3/4] ARM: multi_v7_defconfig: enable STM32 booster regulator

[Fabrice Gasnier]

This enables the driver for STM32 booster regulator found on stm32mp1.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
---
 arch/arm/configs/multi_v7_defconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/configs/multi_v7_defconfig b/arch/arm/configs/multi_v7_defconfig
index 6b748f2..230e7e0 100644
--- a/arch/arm/configs/multi_v7_defconfig
+++ b/arch/arm/configs/multi_v7_defconfig
@@ -568,6 +568,7 @@ CONFIG_REGULATOR_RK808=y
 CONFIG_REGULATOR_RN5T618=y
 CONFIG_REGULATOR_S2MPS11=y
 CONFIG_REGULATOR_S5M8767=y
+CONFIG_REGULATOR_STM32_BOOSTER=m
 CONFIG_REGULATOR_STM32_VREFBUF=m
 CONFIG_REGULATOR_STPMIC1=y
 CONFIG_REGULATOR_TI_ABB=y
-- 
2.7.4

[PATCH 4/4] ARM: dts: stm32: add booster for ADC analog switches on stm32mp157c

[Fabrice Gasnier]

Booster for ADC analog input switches can be used when Vdda is below 2.7V
to get maximum ADC analog performances.
Add booster for ADC analog switches on stm32mp157c.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
---
 arch/arm/boot/dts/stm32mp157c.dtsi | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/arm/boot/dts/stm32mp157c.dtsi b/arch/arm/boot/dts/stm32mp157c.dtsi
index 2afeee6..2dd5162 100644
--- a/arch/arm/boot/dts/stm32mp157c.dtsi
+++ b/arch/arm/boot/dts/stm32mp157c.dtsi
@@ -109,6 +109,12 @@
 		};
 	};
 
+	booster: regulator-booster {
+		compatible = "st,stm32mp1-booster";
+		st,syscfg = <&syscfg>;
+		status = "disabled";
+	};
+
 	soc {
 		compatible = "simple-bus";
 		#address-cells = <1>;
-- 
2.7.4

Re: [PATCH 2/4] regulator: add support for the stm32-booster

[Mark Brown]

[-- Attachment #1: Type: text/plain, Size: 495 bytes --]

On Fri, Jun 28, 2019 at 10:08:07AM +0200, Fabrice Gasnier wrote:
> Add support for the 3.3V booster regulator embedded in stm32h7 and stm32mp1
> devices, that can be used to supply ADC analog input switches.
> 
> This regulator is supplied by vdda. It's controlled by using SYSCFG:
> - STM32H7 has a unique register to set/clear the booster enable bit
> - STM32MP1 has separate set and clear registers to configure it.

This doesn't apply against current code, please check and resend.

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