Add Kinetic KTZ8866 backlight binding documentation.
Signed-off-by: Jianhua Lu <[email protected]>
---
Changes in v2:
- Remove "items" between "compatible" and "const: kinetic,ktz8866".
- Change "additionalProperties" to "unevaluatedProperties".
Changes in v3:
- Add Krzysztof's R-b.
Changes in v4:
- Drop Krzysztof's R-b.
- Add some new properties.
Changes in v5:
- Add missing enum under property description.
- Rename uncorrect properties.
Changes in v6:
- Correct wrong property suffix and description.
Changes in v7:
- Add vddpos and vddeg supply.
- Use enable-gpios instead of defining enable pin.
.../leds/backlight/kinetic,ktz8866.yaml | 74 +++++++++++++++++++
1 file changed, 74 insertions(+)
create mode 100644 Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml
diff --git a/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml b/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml
new file mode 100644
index 000000000000..b1d0ade0dfb6
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml
@@ -0,0 +1,74 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/leds/backlight/kinetic,ktz8866.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Kinetic Technologies KTZ8866 backlight
+
+maintainers:
+ - Jianhua Lu <[email protected]>
+
+description: |
+ The Kinetic Technologies KTZ8866 is a high efficiency 6-channels-current-sinks
+ led backlight with dual lcd bias power.
+ https://www.kinet-ic.com/ktz8866/
+
+allOf:
+ - $ref: common.yaml#
+
+properties:
+ compatible:
+ const: kinetic,ktz8866
+
+ vddpos-supply:
+ description: positive boost supply regulator.
+
+ vddneg-supply:
+ description: negative boost supply regulator.
+
+ enable-gpios:
+ description: GPIO to use to enable/disable the backlight (HWEN pin).
+ maxItems: 1
+
+ current-num-sinks:
+ description: number of the LED current sinks' channels.
+ enum: [1, 2, 3, 4, 5, 6]
+
+ current-ramping-time-ms:
+ description: LED current ramping time in milliseconds.
+ enum: [2, 4, 8, 16, 32, 64, 128, 192, 256, 320, 384, 448, 512, 576, 640]
+
+ led-ramping-time-ms:
+ description: |
+ LED on/off ramping time in milliseconds, note that the case 0 will be mapped
+ to 512μs because ktz8866 can't ramp faster than it.
+ enum: [0, 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384]
+
+ kinetic,enable-lcd-bias:
+ description: Set if we want to output bias power supply for LCD.
+ type: boolean
+
+required:
+ - compatible
+ - vddpos-supply
+ - vddneg-supply
+ - enable-gpios
+
+unevaluatedProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/gpio/gpio.h>
+
+ backlight {
+ compatible = "kinetic,ktz8866";
+
+ vddpos-supply = <&bl_vddpos_5p5>;
+ vddneg-supply = <&bl_vddneg_5p5>;
+ enable-gpios = <&tlmm 139 GPIO_ACTIVE_HIGH>;
+ current-num-sinks = <5>;
+ current-ramping-time-ms = <128>;
+ led-ramping-time-ms = <1>;
+ kinetic,enable-lcd-bias;
+ };
--
2.39.1
Add support for Kinetic KTZ8866 backlight, which is used in
Xiaomi tablet, Mi Pad 5 series. This driver lightly based on
downstream implementation [1].
[1] https://github.com/MiCode/Xiaomi_Kernel_OpenSource/blob/elish-r-oss/drivers/video/backlight/ktz8866.c
Signed-off-by: Jianhua Lu <[email protected]>
---
Changes in v2:
- Add missing staitc modifier to ktz8866_write function.
Changes in v3:
- Add 2022 to Copyright line.
- Sort headers.
- Remove meaningless comment.
- Use definitions instead of hardcoding.
- Add missing maintainer info.
Changes in v4:
- Change 2022 to 2023.
- Remove useless macro and enum.
- Describe settings by devicetree.
- Move header file to C file.
Changes in v5:
- Change "2023" to "2022, 2023" in Copyright line.
- Set scale property for backlight.
Changes in v6:
- Correct devicetree property name.
Changes in v7:
- Remove unnecessary sleep statement.
- Fix code style.
- Add vddpos and vddneg supply devicetree parse.
- Add enabel-gpio devicetree parse.
MAINTAINERS | 6 +
drivers/video/backlight/Kconfig | 8 ++
drivers/video/backlight/Makefile | 1 +
drivers/video/backlight/ktz8866.c | 209 ++++++++++++++++++++++++++++++
4 files changed, 224 insertions(+)
create mode 100644 drivers/video/backlight/ktz8866.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 42fc47c6edfd..2084e74e1b58 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11674,6 +11674,12 @@ M: John Hawley <[email protected]>
S: Maintained
F: tools/testing/ktest
+KTZ8866 BACKLIGHT DRIVER
+M: Jianhua Lu <[email protected]>
+S: Maintained
+F: Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml
+F: drivers/video/backlight/ktz8866.c
+
L3MDEV
M: David Ahern <[email protected]>
L: [email protected]
diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
index 936ba1e4d35e..f7113ceb264a 100644
--- a/drivers/video/backlight/Kconfig
+++ b/drivers/video/backlight/Kconfig
@@ -190,6 +190,14 @@ config BACKLIGHT_KTD253
which is a 1-wire GPIO-controlled backlight found in some mobile
phones.
+config BACKLIGHT_KTZ8866
+ tristate "Backlight Driver for Kinetic KTZ8866"
+ depends on I2C
+ select REGMAP_I2C
+ help
+ Say Y to enable the backlight driver for the Kinetic KTZ8866
+ found in Xiaomi Mi Pad 5 series.
+
config BACKLIGHT_LM3533
tristate "Backlight Driver for LM3533"
depends on MFD_LM3533
diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile
index e815f3f1deff..f70a819c304c 100644
--- a/drivers/video/backlight/Makefile
+++ b/drivers/video/backlight/Makefile
@@ -36,6 +36,7 @@ obj-$(CONFIG_BACKLIGHT_HP680) += hp680_bl.o
obj-$(CONFIG_BACKLIGHT_HP700) += jornada720_bl.o
obj-$(CONFIG_BACKLIGHT_IPAQ_MICRO) += ipaq_micro_bl.o
obj-$(CONFIG_BACKLIGHT_KTD253) += ktd253-backlight.o
+obj-$(CONFIG_BACKLIGHT_KTZ8866) += ktz8866.o
obj-$(CONFIG_BACKLIGHT_LM3533) += lm3533_bl.o
obj-$(CONFIG_BACKLIGHT_LM3630A) += lm3630a_bl.o
obj-$(CONFIG_BACKLIGHT_LM3639) += lm3639_bl.o
diff --git a/drivers/video/backlight/ktz8866.c b/drivers/video/backlight/ktz8866.c
new file mode 100644
index 000000000000..d848345d528f
--- /dev/null
+++ b/drivers/video/backlight/ktz8866.c
@@ -0,0 +1,209 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Backlight driver for the Kinetic KTZ8866
+ *
+ * Copyright (C) 2022, 2023 Jianhua Lu <[email protected]>
+ */
+
+#include <linux/backlight.h>
+#include <linux/err.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+
+#define DEFAULT_BRIGHTNESS 1500
+#define MAX_BRIGHTNESS 2047
+#define REG_MAX 0x15
+
+/* reg */
+#define DEVICE_ID 0x01
+#define BL_CFG1 0x02
+#define BL_CFG2 0x03
+#define BL_BRT_LSB 0x04
+#define BL_BRT_MSB 0x05
+#define BL_EN 0x08
+#define LCD_BIAS_CFG1 0x09
+#define LCD_BIAS_CFG2 0x0A
+#define LCD_BIAS_CFG3 0x0B
+#define LCD_BOOST_CFG 0x0C
+#define OUTP_CFG 0x0D
+#define OUTN_CFG 0x0E
+#define FLAG 0x0F
+#define BL_OPTION1 0x10
+#define BL_OPTION2 0x11
+#define PWM2DIG_LSBs 0x12
+#define PWM2DIG_MSBs 0x13
+#define BL_DIMMING 0x14
+#define PWM_RAMP_TIME 0x15
+
+/* definition */
+#define BL_EN_BIT BIT(6)
+#define LCD_BIAS_EN 0x9F
+#define PWM_HYST 0x5
+
+struct ktz8866 {
+ struct i2c_client *client;
+ struct regmap *regmap;
+ bool led_on;
+ struct gpio_desc *enable_gpio;
+};
+
+static const struct regmap_config ktz8866_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .max_register = REG_MAX,
+};
+
+static int ktz8866_write(struct ktz8866 *ktz, unsigned int reg,
+ unsigned int val)
+{
+ return regmap_write(ktz->regmap, reg, val);
+}
+
+static int ktz8866_update_bits(struct ktz8866 *ktz, unsigned int reg,
+ unsigned int mask, unsigned int val)
+{
+ return regmap_update_bits(ktz->regmap, reg, mask, val);
+}
+
+static int ktz8866_backlight_update_status(struct backlight_device *backlight_dev)
+{
+ struct ktz8866 *ktz = bl_get_data(backlight_dev);
+ unsigned int brightness = backlight_get_brightness(backlight_dev);
+
+ if (!ktz->led_on && brightness > 0) {
+ ktz8866_update_bits(ktz, BL_EN, BL_EN_BIT, BL_EN_BIT);
+ ktz->led_on = true;
+ } else if (brightness == 0) {
+ ktz8866_update_bits(ktz, BL_EN, BL_EN_BIT, 0);
+ ktz->led_on = false;
+ }
+
+ /* Set brightness */
+ ktz8866_write(ktz, BL_BRT_LSB, brightness & 0x7);
+ ktz8866_write(ktz, BL_BRT_MSB, (brightness >> 3) & 0xFF);
+
+ return 0;
+}
+
+static const struct backlight_ops ktz8866_backlight_ops = {
+ .options = BL_CORE_SUSPENDRESUME,
+ .update_status = ktz8866_backlight_update_status,
+};
+
+static void ktz8866_init(struct ktz8866 *ktz)
+{
+ unsigned int val = 0;
+
+ if (of_property_read_u32(ktz->client->dev.of_node, "current-num-sinks", &val))
+ ktz8866_write(ktz, BL_EN, BIT(val) - 1);
+ else
+ /* Enable all 6 current sinks if the number of current sinks isn't specified. */
+ ktz8866_write(ktz, BL_EN, BIT(6) - 1);
+
+ if (of_property_read_u32(ktz->client->dev.of_node, "current-ramping-time-ms", &val)) {
+ if (val <= 128)
+ ktz8866_write(ktz, BL_CFG2, BIT(7) | (ilog2(val) << 3) | PWM_HYST);
+ else
+ ktz8866_write(ktz, BL_CFG2, BIT(7) | ((5 + val / 64) << 3) | PWM_HYST);
+ }
+
+ if (of_property_read_u32(ktz->client->dev.of_node, "led-ramping-time-ms", &val)) {
+ if (val == 0)
+ ktz8866_write(ktz, BL_DIMMING, 0);
+ else {
+ unsigned int ramp_off_time = ilog2(val) + 1;
+ unsigned int ramp_on_time = ramp_off_time << 4;
+ ktz8866_write(ktz, BL_DIMMING, ramp_on_time | ramp_off_time);
+ }
+ }
+
+ if (of_property_read_bool(ktz->client->dev.of_node, "kinetic,enable-lcd-bias"))
+ ktz8866_write(ktz, LCD_BIAS_CFG1, LCD_BIAS_EN);
+}
+
+static int ktz8866_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct backlight_device *backlight_dev;
+ struct backlight_properties props;
+ struct ktz8866 *ktz;
+ int ret = 0;
+
+ ktz = devm_kzalloc(&client->dev, sizeof(*ktz), GFP_KERNEL);
+ if (!ktz)
+ return -ENOMEM;
+
+ ktz->client = client;
+ ktz->regmap = devm_regmap_init_i2c(client, &ktz8866_regmap_config);
+ if (IS_ERR(ktz->regmap))
+ return dev_err_probe(&client->dev, PTR_ERR(ktz->regmap), "failed to init regmap\n");
+
+ ret = devm_regulator_get_enable(&client->dev, "vddpos");
+ if (ret)
+ return dev_err_probe(&client->dev, ret, "get regulator vddpos failed\n");
+ ret = devm_regulator_get_enable(&client->dev, "vddneg");
+ if (ret)
+ return dev_err_probe(&client->dev, ret, "get regulator vddneg failed\n");
+
+ ktz->enable_gpio = devm_gpiod_get_optional(&client->dev, "enable", GPIOD_OUT_HIGH);
+ if (IS_ERR(ktz->enable_gpio))
+ return PTR_ERR(ktz->enable_gpio);
+
+ memset(&props, 0, sizeof(props));
+ props.type = BACKLIGHT_RAW;
+ props.max_brightness = MAX_BRIGHTNESS;
+ props.brightness = DEFAULT_BRIGHTNESS;
+ props.scale = BACKLIGHT_SCALE_LINEAR;
+
+ backlight_dev = devm_backlight_device_register(&client->dev, "ktz8866-backlight",
+ &client->dev, ktz, &ktz8866_backlight_ops, &props);
+ if (IS_ERR(backlight_dev))
+ return dev_err_probe(&client->dev, PTR_ERR(backlight_dev),
+ "failed to register backlight device\n");
+
+ ktz8866_init(ktz);
+
+ i2c_set_clientdata(client, backlight_dev);
+ backlight_update_status(backlight_dev);
+
+ return 0;
+}
+
+static void ktz8866_remove(struct i2c_client *client)
+{
+ struct backlight_device *backlight_dev = i2c_get_clientdata(client);
+ backlight_dev->props.brightness = 0;
+ backlight_update_status(backlight_dev);
+}
+
+static const struct i2c_device_id ktz8866_ids[] = {
+ { "ktz8866", 0 },
+ {},
+};
+MODULE_DEVICE_TABLE(i2c, ktz8866_ids);
+
+static const struct of_device_id ktz8866_match_table[] = {
+ {
+ .compatible = "kinetic,ktz8866",
+ },
+ {},
+};
+
+static struct i2c_driver ktz8866_driver = {
+ .driver = {
+ .name = "ktz8866",
+ .of_match_table = ktz8866_match_table,
+ },
+ .probe = ktz8866_probe,
+ .remove = ktz8866_remove,
+ .id_table = ktz8866_ids,
+};
+
+module_i2c_driver(ktz8866_driver);
+
+MODULE_DESCRIPTION("Kinetic KTZ8866 Backlight Driver");
+MODULE_AUTHOR("Jianhua Lu <[email protected]>");
+MODULE_LICENSE("GPL");
--
2.39.1
On 20/01/2023 10:47, Jianhua Lu wrote:
> Add Kinetic KTZ8866 backlight binding documentation.
>
> Signed-off-by: Jianhua Lu <[email protected]>
> ---
> Changes in v2:
> - Remove "items" between "compatible" and "const: kinetic,ktz8866".
> - Change "additionalProperties" to "unevaluatedProperties".
>
> Changes in v3:
> - Add Krzysztof's R-b.
>
> Changes in v4:
> - Drop Krzysztof's R-b.
> - Add some new properties.
>
> Changes in v5:
> - Add missing enum under property description.
> - Rename uncorrect properties.
>
> Changes in v6:
> - Correct wrong property suffix and description.
>
> Changes in v7:
> - Add vddpos and vddeg supply.
> - Use enable-gpios instead of defining enable pin.
>
> .../leds/backlight/kinetic,ktz8866.yaml | 74 +++++++++++++++++++
> 1 file changed, 74 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml
>
> diff --git a/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml b/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml
> new file mode 100644
> index 000000000000..b1d0ade0dfb6
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml
> @@ -0,0 +1,74 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/leds/backlight/kinetic,ktz8866.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Kinetic Technologies KTZ8866 backlight
> +
> +maintainers:
> + - Jianhua Lu <[email protected]>
> +
> +description: |
> + The Kinetic Technologies KTZ8866 is a high efficiency 6-channels-current-sinks
> + led backlight with dual lcd bias power.
> + https://www.kinet-ic.com/ktz8866/
> +
> +allOf:
> + - $ref: common.yaml#
> +
> +properties:
> + compatible:
> + const: kinetic,ktz8866
> +
> + vddpos-supply:
> + description: positive boost supply regulator.
> +
> + vddneg-supply:
> + description: negative boost supply regulator.
> +
> + enable-gpios:
> + description: GPIO to use to enable/disable the backlight (HWEN pin).
> + maxItems: 1
> +
> + current-num-sinks:
> + description: number of the LED current sinks' channels.
> + enum: [1, 2, 3, 4, 5, 6]
> +
> + current-ramping-time-ms:
> + description: LED current ramping time in milliseconds.
> + enum: [2, 4, 8, 16, 32, 64, 128, 192, 256, 320, 384, 448, 512, 576, 640]
kinetic,current-ramp-delay-ms
> +
> + led-ramping-time-ms:
kinetic,led-enable-ramp-delay-ms
So both are similar to existing regulator properties.
Best regards,
Krzysztof
On Fri, Jan 20, 2023 at 11:18:56AM +0100, Krzysztof Kozlowski wrote:
> On 20/01/2023 10:47, Jianhua Lu wrote:
> > Add Kinetic KTZ8866 backlight binding documentation.
> >
> > Signed-off-by: Jianhua Lu <[email protected]>
> > ---
> > Changes in v2:
> > - Remove "items" between "compatible" and "const: kinetic,ktz8866".
> > - Change "additionalProperties" to "unevaluatedProperties".
> >
> > Changes in v3:
> > - Add Krzysztof's R-b.
> >
> > Changes in v4:
> > - Drop Krzysztof's R-b.
> > - Add some new properties.
> >
> > Changes in v5:
> > - Add missing enum under property description.
> > - Rename uncorrect properties.
> >
> > Changes in v6:
> > - Correct wrong property suffix and description.
> >
> > Changes in v7:
> > - Add vddpos and vddeg supply.
> > - Use enable-gpios instead of defining enable pin.
> >
> > .../leds/backlight/kinetic,ktz8866.yaml | 74 +++++++++++++++++++
> > 1 file changed, 74 insertions(+)
> > create mode 100644 Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml b/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml
> > new file mode 100644
> > index 000000000000..b1d0ade0dfb6
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml
> > @@ -0,0 +1,74 @@
> > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/leds/backlight/kinetic,ktz8866.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Kinetic Technologies KTZ8866 backlight
> > +
> > +maintainers:
> > + - Jianhua Lu <[email protected]>
> > +
> > +description: |
> > + The Kinetic Technologies KTZ8866 is a high efficiency 6-channels-current-sinks
> > + led backlight with dual lcd bias power.
> > + https://www.kinet-ic.com/ktz8866/
> > +
> > +allOf:
> > + - $ref: common.yaml#
> > +
> > +properties:
> > + compatible:
> > + const: kinetic,ktz8866
> > +
> > + vddpos-supply:
> > + description: positive boost supply regulator.
> > +
> > + vddneg-supply:
> > + description: negative boost supply regulator.
> > +
> > + enable-gpios:
> > + description: GPIO to use to enable/disable the backlight (HWEN pin).
> > + maxItems: 1
> > +
> > + current-num-sinks:
> > + description: number of the LED current sinks' channels.
> > + enum: [1, 2, 3, 4, 5, 6]
> > +
> > + current-ramping-time-ms:
> > + description: LED current ramping time in milliseconds.
> > + enum: [2, 4, 8, 16, 32, 64, 128, 192, 256, 320, 384, 448, 512, 576, 640]
>
> kinetic,current-ramp-delay-ms
>
> > +
> > + led-ramping-time-ms:
>
> kinetic,led-enable-ramp-delay-ms
>
> So both are similar to existing regulator properties.
>
reasonable suggestion.
> Best regards,
> Krzysztof
>
On Fri, Jan 20, 2023 at 03:22:09PM +0000, Daniel Thompson wrote:
> On Fri, Jan 20, 2023 at 05:47:27PM +0800, Jianhua Lu wrote:
> > Add Kinetic KTZ8866 backlight binding documentation.
> >
> > Signed-off-by: Jianhua Lu <[email protected]>
> > [...]
> >
> > diff --git a/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml b/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml
> > new file mode 100644
> > index 000000000000..b1d0ade0dfb6
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml
> > @@ -0,0 +1,74 @@
> > [...]
> > + current-ramping-time-ms:
> > + description: LED current ramping time in milliseconds.
> > + enum: [2, 4, 8, 16, 32, 64, 128, 192, 256, 320, 384, 448, 512, 576, 640]
>
> This doesn't look like it goes low enough (wasn't there a value lower
> than 2?).
>
Yes, I have sent a v8 patch to add it.
Thanks for reply.
>
> Daniel.
On Fri, Jan 20, 2023 at 05:47:27PM +0800, Jianhua Lu wrote:
> Add Kinetic KTZ8866 backlight binding documentation.
>
> Signed-off-by: Jianhua Lu <[email protected]>
> [...]
>
> diff --git a/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml b/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml
> new file mode 100644
> index 000000000000..b1d0ade0dfb6
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml
> @@ -0,0 +1,74 @@
> [...]
> + current-ramping-time-ms:
> + description: LED current ramping time in milliseconds.
> + enum: [2, 4, 8, 16, 32, 64, 128, 192, 256, 320, 384, 448, 512, 576, 640]
This doesn't look like it goes low enough (wasn't there a value lower
than 2?).
Daniel.
On Fri, Jan 20, 2023 at 03:22:09PM +0000, Daniel Thompson wrote:
> On Fri, Jan 20, 2023 at 05:47:27PM +0800, Jianhua Lu wrote:
> > Add Kinetic KTZ8866 backlight binding documentation.
> >
> > Signed-off-by: Jianhua Lu <[email protected]>
> > [...]
> >
> > diff --git a/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml b/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml
> > new file mode 100644
> > index 000000000000..b1d0ade0dfb6
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml
> > @@ -0,0 +1,74 @@
> > [...]
> > + current-ramping-time-ms:
> > + description: LED current ramping time in milliseconds.
> > + enum: [2, 4, 8, 16, 32, 64, 128, 192, 256, 320, 384, 448, 512, 576, 640]
>
> This doesn't look like it goes low enough (wasn't there a value lower
> than 2?).
Sorry, I sent a wrong message, it isn't be fixed in v8,
I send a v9 patch to add it.
>
>
> Daniel.