Add a YAML devicetree binding for the Richtek RT8515
dual channel flash/torch LED driver.
Cc: Sakari Ailus <sakari.ailus@xxxxxx>
Cc: newbytee@xxxxxxxxxxxxxx
Cc: Stephan Gerhold <stephan@xxxxxxxxxxx>
Cc: phone-devel@xxxxxxxxxxxxxxx
Cc: linux-media@xxxxxxxxxxxxxxx
Cc: devicetree@xxxxxxxxxxxxxxx
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
---
ChangeLog v3->v4:
- Add DT attributes for the RFS and RTS resistors, so that
the hardware-defined maximum current can be determined.
- Add torch-max-microamp to the common bindings so we can
set an attribute for the max microamp in torch mode.
- Add flash-max-microamp and torch-max-microamp as optional
to the LED node.
- Slot in some elabortative descriptions of the new
properties and describe what the hardware is doing.
- Cc phone-devel@xxxxxxxxxxxxxxx
ChangeLog v2->v3:
- Add Sakari to CC
- Resend
ChangeLog v1->v2:
- Explicitly inherit function, color and flash-max-timeout-us
from common.yaml
- Add "led" node as required.
---
.../devicetree/bindings/leds/common.yaml | 6 +
.../bindings/leds/richtek,rt8515.yaml | 111 ++++++++++++++++++
2 files changed, 117 insertions(+)
create mode 100644 Documentation/devicetree/bindings/leds/richtek,rt8515.yaml
diff --git a/Documentation/devicetree/bindings/leds/common.yaml b/Documentation/devicetree/bindings/leds/common.yaml
index 08b6700ca61e..28bdf09b4af4 100644
--- a/Documentation/devicetree/bindings/leds/common.yaml
+++ b/Documentation/devicetree/bindings/leds/common.yaml
@@ -151,6 +151,12 @@ properties:
Maximum flash LED supply current in microamperes. Required for flash LED
nodes with configurable current.
+ torch-max-microamp:
+ description:
+ Maximum flash LED supply current in microamperes, when the flash LED is
+ used as a torch (flashlight). This is usually lower than the flash mode
+ maximum current, if the LED supports torch mode.
+
flash-max-timeout-us:
description:
Maximum timeout in microseconds after which the flash LED is turned off.
diff --git a/Documentation/devicetree/bindings/leds/richtek,rt8515.yaml b/Documentation/devicetree/bindings/leds/richtek,rt8515.yaml
new file mode 100644
index 000000000000..5f65a20b997d
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/richtek,rt8515.yaml
@@ -0,0 +1,111 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/leds/richtek,rt8515.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Richtek RT8515 1.5A dual channel LED driver
+
+maintainers:
+ - Linus Walleij <linus.walleij@xxxxxxxxxx>
+
+description: |
+ The Richtek RT8515 is a dual channel (two mode) LED driver that
+ supports driving a white LED in flash or torch mode. The maximum
+ current for each mode is defined in hardware using two resistors
+ RFS and RTS.
+
+properties:
+ compatible:
+ const: richtek,rt8515
+
+ enf-gpios:
+ maxItems: 1
+ description: A connection to the 'ENF' (enable flash) pin.
+
+ ent-gpios:
+ maxItems: 1
+ description: A connection to the 'ENT' (enable torch) pin.
+
+ richtek,rfs:
+ maxItems: 1
+ minimum: 7680
+ maximum: 367000
+ description: The resistance value of the RFS resisitor. This
+ resistors limits the maximum flash current. This must be set
+ for the property flash-max-microamp to work, the RFS resistor
+ defines the range of the dimmer setting (brightness) of the
+ flash LED.
+
+ richtek,rts:
+ maxItems: 1
+ minimum: 7680
+ maximum: 367000
+ description: The resistance value of the RTS resisitor. This
+ resistors limits the maximum torch current. This must be set
+ for the property torch-max-microamp to work, the RTS resistor
+ defines the range of the dimmer setting (brightness) of the
+ torch LED.
+
+ led:
+ type: object
+ $ref: common.yaml#
+ properties:
+ function: true
+ color: true
+ flash-max-timeout-us: true
+
+ flash-max-microamp:
+ maximum: 700000
+ description: The maximum current for flash mode
+ is hardwired to the component using the RFS resistor to
+ ground. The maximum hardware current setting is calculated
+ according to the formula Imax = 5500 / RFS. The lowest
+ allowed resistance value is 7.86 kOhm giving an absolute
+ maximum current of 700mA. By setting this attribute in
+ the device tree, you can further restrict the maximum
+ current below the hardware limit. This requires the RFS
+ to be defined as it defines the maximum range.
+
+ torch-max-microamp:
+ maximum: 700000
+ description: The maximum current for torch mode
+ is hardwired to the component using the RTS resistor to
+ ground. The maximum hardware current setting is calculated
+ according to the formula Imax = 5500 / RTS. The lowest
+ allowed resistance value is 7.86 kOhm giving an absolute
+ maximum current of 700mA. By setting this attribute in
+ the device tree, you can further restrict the maximum
+ current below the hardware limit. This requires the RTS
+ to be defined as it defines the maximum range.
+
+required:
+ - compatible
+ - ent-gpios
+ - enf-gpios
+ - led
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/gpio/gpio.h>
+ #include <dt-bindings/leds/common.h>
+
+ led-controller {
+ compatible = "richtek,rt8515";
+ enf-gpios = <&gpio4 12 GPIO_ACTIVE_HIGH>;
+ ent-gpios = <&gpio4 13 GPIO_ACTIVE_HIGH>;
+ richtek,rfs = <16000>;
+ richtek,rts = <100000>;
+
+ led {
+ function = LED_FUNCTION_FLASH;
+ color = <LED_COLOR_ID_WHITE>;
+ flash-max-timeout-us = <250000>;
+ flash-max-microamp = <150000>;
+ torch-max-microamp = <25000>;
+ };
+ };
+
+...
--
2.26.2
