[PATCH 0/2] regulator: fixed: add off-on-delay-us

[PATCH 0/2] regulator: fixed: add off-on-delay-us

[Peng Fan]

From: Peng Fan <peng.fan@nxp.com>

Depends on board design, the gpio controlled fixed regulator might
connect with a large capacitance. It needs time to be truly off when
disabling the regulator. If the delay is not enought, the voltage might
not drop to the expected value, such as 0, then the regulator might
have been always enabled. So introduce off-on-delay-us property and
add the support in fixed regualtor driver.

Peng Fan (2):
  dt-bindings: regulator: fixed: add off-on-delay-us property
  regulator: fixed: add off-on-delay

 Documentation/devicetree/bindings/regulator/fixed-regulator.yaml | 4 ++++
 drivers/regulator/fixed.c                                        | 2 ++
 include/linux/regulator/fixed.h                                  | 1 +
 3 files changed, 7 insertions(+)

-- 
2.16.4

[PATCH 1/2] dt-bindings: regulator: fixed: add off-on-delay-us property

[Peng Fan]

From: Peng Fan <peng.fan@nxp.com>

When disabling a fixed regulator, it may take some time to let the
voltage drop to the expected value, such as zero. If not delay
enough time, the regulator might have been always enabled.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
---
 Documentation/devicetree/bindings/regulator/fixed-regulator.yaml | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Documentation/devicetree/bindings/regulator/fixed-regulator.yaml b/Documentation/devicetree/bindings/regulator/fixed-regulator.yaml
index a78150c47aa2..954130a8ccbe 100644
--- a/Documentation/devicetree/bindings/regulator/fixed-regulator.yaml
+++ b/Documentation/devicetree/bindings/regulator/fixed-regulator.yaml
@@ -50,6 +50,10 @@ properties:
     description: startup time in microseconds
     $ref: /schemas/types.yaml#/definitions/uint32
 
+  off-on-delay-us:
+    description: off delay time in microseconds
+    $ref: /schemas/types.yaml#/definitions/uint32
+
   enable-active-high:
     description:
       Polarity of GPIO is Active high. If this property is missing,
-- 
2.16.4

[PATCH 2/2] regulator: fixed: add off-on-delay

[Peng Fan]

From: Peng Fan <peng.fan@nxp.com>

Depends on board design, the gpio controlling regulator may
connects with a big capacitance. When need off, it takes some time
to let the regulator to be truly off. If not add enough delay, the
regulator might have always been on, so introduce off-on-delay to
handle such case.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
---

V1:
 There is a checkpatch warning "
 Prefer 'unsigned int' to bare use of 'unsigned' ",
 so I use unsigned int for off_on_delay.

 drivers/regulator/fixed.c       | 2 ++
 include/linux/regulator/fixed.h | 1 +
 2 files changed, 3 insertions(+)

diff --git a/drivers/regulator/fixed.c b/drivers/regulator/fixed.c
index d90a6fd8cbc7..5dbdc41743f3 100644
--- a/drivers/regulator/fixed.c
+++ b/drivers/regulator/fixed.c
@@ -123,6 +123,7 @@ of_get_fixed_voltage_config(struct device *dev,
 		config->enabled_at_boot = true;
 
 	of_property_read_u32(np, "startup-delay-us", &config->startup_delay);
+	of_property_read_u32(np, "off-on-delay-us", &config->off_on_delay);
 
 	if (of_find_property(np, "vin-supply", NULL))
 		config->input_supply = "vin";
@@ -190,6 +191,7 @@ static int reg_fixed_voltage_probe(struct platform_device *pdev)
 	}
 
 	drvdata->desc.enable_time = config->startup_delay;
+	drvdata->desc.off_on_delay = config->off_on_delay;
 
 	if (config->input_supply) {
 		drvdata->desc.supply_name = devm_kstrdup(&pdev->dev,
diff --git a/include/linux/regulator/fixed.h b/include/linux/regulator/fixed.h
index d44ce5f18a56..623a5c574782 100644
--- a/include/linux/regulator/fixed.h
+++ b/include/linux/regulator/fixed.h
@@ -36,6 +36,7 @@ struct fixed_voltage_config {
 	const char *input_supply;
 	int microvolts;
 	unsigned startup_delay;
+	unsigned int off_on_delay;
 	unsigned enabled_at_boot:1;
 	struct regulator_init_data *init_data;
 };
-- 
2.16.4