[PATCH v3 0/2] power: supply: gpio-charger: add support for default charge current limit

[PATCH v3 0/2] power: supply: gpio-charger: add support for default charge current limit

[Dimitri Fedrau via B4 Relay]

With DT properties charge-current-limit-gpios and
charge-current-limit-mapping one can define charge current limits in uA
using up to 32 GPIOs. At the moment the driver defaults to smallest charge
current limitation for safety reasons. When disabling charging is
supported, which should be common, the driver defaults to non charging on
probe. By having a default, charging can be enabled on probe for such
devices.

Signed-off-by: Dimitri Fedrau <dimitri.fedrau@liebherr.com>
---
Changes in v3:
- Fix commit msg for "dt-bindings: power: supply: gpio-charger: add support for default charge current limit"
  Add use case
- Link to v2: https://lore.kernel.org/r/20241213-default-charge-current-limit-v2-0-45886fce905c@liebherr.com

Changes in v2:
- renamed DT property charge-current-limit-default to
  charge-current-limit-default-microamp
- Added dependency on charge-current-limit-mapping
- Added intention and use case to commit descriptions
- Added charge-current-limit-default-microamp in bindings example
- Link to v1: https://lore.kernel.org/r/20241211-default-charge-current-limit-v1-0-7819ba06ee2a@liebherr.com

---
Dimitri Fedrau (2):
      dt-bindings: power: supply: gpio-charger: add support for default charge current limit
      power: supply: gpio-charger: add support for default charge current limit

 .../devicetree/bindings/power/supply/gpio-charger.yaml      |  6 ++++++
 drivers/power/supply/gpio-charger.c                         | 13 +++++++++++++
 2 files changed, 19 insertions(+)
---
base-commit: 57cb041f61d4abcf8dfa41259df27d081ab4cb6a
change-id: 20241209-default-charge-current-limit-69ae7945061a

Best regards,
-- 
Dimitri Fedrau <dimitri.fedrau@liebherr.com>

[PATCH v3 1/2] dt-bindings: power: supply: gpio-charger: add support for default charge current limit

[Dimitri Fedrau via B4 Relay]

From: Dimitri Fedrau <dimitri.fedrau@liebherr.com>

With DT properties charge-current-limit-gpios and
charge-current-limit-mapping one can define charge current limits in uA
using up to 32 GPIOs. Add property charge-current-limit-default-microamp
which selects a default charge current limit that must be listed in
charge-current-limit-mapping.
This is helpful when the smallest possible charge current limit is 0uA. The
driver defaults to the smallest possible value at the moment, which
disables charging on probe. With the default its possible to setup a safe
charge current limit.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Dimitri Fedrau <dimitri.fedrau@liebherr.com>
---
 Documentation/devicetree/bindings/power/supply/gpio-charger.yaml | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Documentation/devicetree/bindings/power/supply/gpio-charger.yaml b/Documentation/devicetree/bindings/power/supply/gpio-charger.yaml
index 89f8e2bcb2d7836c6a4308aff51721bd83fa3ba1..25826bfc289c1c00c338fd0cee2ae6932529cfc3 100644
--- a/Documentation/devicetree/bindings/power/supply/gpio-charger.yaml
+++ b/Documentation/devicetree/bindings/power/supply/gpio-charger.yaml
@@ -58,6 +58,10 @@ properties:
             charge-current-limit-gpios property. Bit 1 second to last
             GPIO and so on.
 
+  charge-current-limit-default-microamp:
+    description: Default charge current limit. Must be listed in
+      charge-current-limit-mapping.
+
 required:
   - compatible
 
@@ -72,6 +76,7 @@ anyOf:
 dependencies:
   charge-current-limit-gpios: [ charge-current-limit-mapping ]
   charge-current-limit-mapping: [ charge-current-limit-gpios ]
+  charge-current-limit-default-microamp: [charge-current-limit-mapping]
 
 additionalProperties: false
 
@@ -91,4 +96,5 @@ examples:
       charge-current-limit-mapping = <2500000 0x00>, // 2.5 A => both GPIOs low
                                      <700000 0x01>, // 700 mA => GPIO A.12 high
                                      <0 0x02>; // 0 mA => GPIO A.11 high
+      charge-current-limit-default-microamp = <700000>;
     };

-- 
2.39.5

[PATCH v3 2/2] power: supply: gpio-charger: add support for default charge current limit

[Dimitri Fedrau via B4 Relay]

From: Dimitri Fedrau <dimitri.fedrau@liebherr.com>

With DT properties charge-current-limit-gpios and
charge-current-limit-mapping one can define charge current limits in uA
using up to 32 GPIOs. At the moment the driver defaults to smallest charge
current limitation for safety reasons. When disabling charging is
supported, which should be common, the driver defaults to non charging on
probe. By having a default, charging can be enabled on probe for such
devices.

Signed-off-by: Dimitri Fedrau <dimitri.fedrau@liebherr.com>
---
 drivers/power/supply/gpio-charger.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/power/supply/gpio-charger.c b/drivers/power/supply/gpio-charger.c
index 68212b39785beabfe5536a18fa15bc249f7b1eea..56149545a1dc6004b474cec44984c6dfad3413b5 100644
--- a/drivers/power/supply/gpio-charger.c
+++ b/drivers/power/supply/gpio-charger.c
@@ -187,6 +187,8 @@ static int init_charge_current_limit(struct device *dev,
 {
 	int i, len;
 	u32 cur_limit = U32_MAX;
+	bool set_def_limit;
+	u32 def_limit;
 
 	gpio_charger->current_limit_gpios = devm_gpiod_get_array_optional(dev,
 		"charge-current-limit", GPIOD_OUT_LOW);
@@ -220,6 +222,9 @@ static int init_charge_current_limit(struct device *dev,
 	if (len < 0)
 		return len;
 
+	set_def_limit = !device_property_read_u32(dev,
+						  "charge-current-limit-default-microamp",
+						  &def_limit);
 	for (i=0; i < gpio_charger->current_limit_map_size; i++) {
 		if (gpio_charger->current_limit_map[i].limit_ua > cur_limit) {
 			dev_err(dev, "charge-current-limit-mapping not sorted by current in descending order\n");
@@ -227,8 +232,16 @@ static int init_charge_current_limit(struct device *dev,
 		}
 
 		cur_limit = gpio_charger->current_limit_map[i].limit_ua;
+		if (set_def_limit && def_limit == cur_limit) {
+			set_charge_current_limit(gpio_charger, cur_limit);
+			return 0;
+		}
 	}
 
+	if (set_def_limit)
+		dev_warn(dev, "charge-current-limit-default-microamp %u not listed in charge-current-limit-mapping\n",
+			 def_limit);
+
 	/* default to smallest current limitation for safety reasons */
 	len = gpio_charger->current_limit_map_size - 1;
 	set_charge_current_limit(gpio_charger,

-- 
2.39.5

Re: [PATCH v3 0/2] power: supply: gpio-charger: add support for default charge current limit

[Sebastian Reichel]

On Wed, 18 Dec 2024 09:34:59 +0100, Dimitri Fedrau wrote:
> With DT properties charge-current-limit-gpios and
> charge-current-limit-mapping one can define charge current limits in uA
> using up to 32 GPIOs. At the moment the driver defaults to smallest charge
> current limitation for safety reasons. When disabling charging is
> supported, which should be common, the driver defaults to non charging on
> probe. By having a default, charging can be enabled on probe for such
> devices.
> 
> [...]

Applied, thanks!

[1/2] dt-bindings: power: supply: gpio-charger: add support for default charge current limit
      commit: 0a219d6fd7ab89177a6fa49539def43694154d50
[2/2] power: supply: gpio-charger: add support for default charge current limit
      commit: de68987480cb92702eab14cf62ec2aa1bae5c867

Best regards,
-- 
Sebastian Reichel <sebastian.reichel@collabora.com>