This patch supports KTD2692 flash LED driver
Ingi Kim (3):
of: Add vendor prefix for Kinetic technologies
leds: ktd2692: add device tree bindings for ktd2692
leds: Add ktd2692 flash LED driver
.../devicetree/bindings/leds/leds-ktd2692.txt | 19 ++
.../devicetree/bindings/vendor-prefixes.txt | 1 +
drivers/leds/Kconfig | 8 +
drivers/leds/Makefile | 1 +
drivers/leds/leds-ktd2692.c | 245 ++++++++++++++++++++
5 files changed, 274 insertions(+)
create mode 100644 Documentation/devicetree/bindings/leds/leds-ktd2692.txt
create mode 100644 drivers/leds/leds-ktd2692.c
--
1.7.9.5
This patch adds vendor prefix for Kinetic technologies
Signed-off-by: Ingi Kim <[email protected]>
---
.../devicetree/bindings/vendor-prefixes.txt | 1 +
1 file changed, 1 insertion(+)
diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
index 389ca13..de9e126 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.txt
+++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
@@ -98,6 +98,7 @@ isee ISEE 2007 S.L.
isil Intersil
karo Ka-Ro electronics GmbH
keymile Keymile GmbH
+kinetic Kinetic Technologies
lacie LaCie
lantiq Lantiq Semiconductor
lenovo Lenovo Group Ltd.
--
1.7.9.5
This patch adds the device tree bindings for ktd2692 flash LEDs
Signed-off-by: Ingi Kim <[email protected]>
---
.../devicetree/bindings/leds/leds-ktd2692.txt | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)
create mode 100644 Documentation/devicetree/bindings/leds/leds-ktd2692.txt
diff --git a/Documentation/devicetree/bindings/leds/leds-ktd2692.txt b/Documentation/devicetree/bindings/leds/leds-ktd2692.txt
new file mode 100644
index 0000000..b68faa6
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/leds-ktd2692.txt
@@ -0,0 +1,19 @@
+* Kinetic Technologies - KTD2692 Flash LED Driver
+
+KTD2692 is the ideal power solution for high-power flash LEDs.
+It uses ExpressWire single-wire programming for maximum flexibility.
+
+Required properties:
+ - compatible: "kinetic,ktd2692"
+ - strobe-gpio: gpio pin to control movie mode current level.
+ - torch-gpio: gpio pin to control ON/OFF flash mode
+ as a higher priority over strobe-gpio.
+
+Example:
+
+flash-led {
+ compatible = "kinetic,ktd2692";
+ strobe-gpio = <&gpc0 1 0>;
+ torch-gpio = <&gpc0 2 0>;
+ status = "okay";
+};
--
1.7.9.5
This patch adds a driver to support the ktd2692 flash LEDs.
ktd2692 can control flash current by ExpressWire interface.
Signed-off-by: Ingi Kim <[email protected]>
---
drivers/leds/Kconfig | 8 ++
drivers/leds/Makefile | 1 +
drivers/leds/leds-ktd2692.c | 245 +++++++++++++++++++++++++++++++++++++++++++
3 files changed, 254 insertions(+)
create mode 100644 drivers/leds/leds-ktd2692.c
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 25b320d..f8870db 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -526,6 +526,14 @@ config LEDS_VERSATILE
This option enabled support for the LEDs on the ARM Versatile
and RealView boards. Say Y to enabled these.
+config LEDS_KTD2692
+ tristate "LED support for the KTD2692 Driver"
+ depends on LEDS_CLASS
+ depends on GPIOLIB
+ help
+ This option enables support for the KTD2692 connected through
+ ExpressWire Interface. Say Y to enable these.
+
comment "LED Triggers"
source "drivers/leds/trigger/Kconfig"
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index cbba921..289513b 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -58,6 +58,7 @@ obj-$(CONFIG_LEDS_BLINKM) += leds-blinkm.o
obj-$(CONFIG_LEDS_SYSCON) += leds-syscon.o
obj-$(CONFIG_LEDS_VERSATILE) += leds-versatile.o
obj-$(CONFIG_LEDS_MENF21BMC) += leds-menf21bmc.o
+obj-$(CONFIG_LEDS_KTD2692) += leds-ktd2692.o
# LED SPI Drivers
obj-$(CONFIG_LEDS_DAC124S085) += leds-dac124s085.o
diff --git a/drivers/leds/leds-ktd2692.c b/drivers/leds/leds-ktd2692.c
new file mode 100644
index 0000000..9c98689
--- /dev/null
+++ b/drivers/leds/leds-ktd2692.c
@@ -0,0 +1,245 @@
+/*
+ * Kinetic Technologies KTD2692 Flash LED Driver
+ *
+ * Copyright (C) 2015 Samsung Electronics
+ * Ingi Kim <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/leds.h>
+#include <linux/of_gpio.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+
+#define GET_BIT(bit, val) (((val) >> (bit)) & 0x01)
+
+/* Adjust a multiple of brightness */
+#define KTD2692_BRIGHTNESS_RANGE_255_TO_16(x) (((x) >> 4) & 0x0F)
+#define KTD2692_BRIGHTNESS_RANGE_255_TO_8(x) (((x) >> 5) & 0x0F)
+#define KTD2692_BRIGHTNESS_RANGE_255_TO_4(x) (((x) >> 6) & 0x0F)
+
+/* Base register address */
+#define KTD2692_REG_LVP_BASE 0x00
+#define KTD2692_REG_FLASH_TIMEOUT_BASE 0x20
+#define KTD2692_REG_MIN_CURRENT_SET_BASE 0x40
+#define KTD2692_REG_MOVIE_CURRENT_BASE 0x60
+#define KTD2692_REG_FLASH_CURRENT_BASE 0x80
+#define KTD2692_REG_MODE_BASE 0xA0
+
+/* Set bit coding time for expresswire interface */
+#define KTD2692_TIME_RESET_US 700
+#define KTD2692_TIME_DATA_START_TIME_US 10
+#define KTD2692_TIME_HIGH_END_OF_DATA_US 350
+#define KTD2692_TIME_LOW_END_OF_DATA_US 10
+#define KTD2692_TIME_SHORT_BITSET_US 4
+#define KTD2692_TIME_LONG_BITSET_US 12
+
+/* KTD2692 default length of name */
+#define KTD2692_NAME_LENGTH 20
+
+/* KTD2692 default name */
+#define KTD2692_DEFAULT_NAME "ktd2692"
+
+enum ktd2692_mode {
+ KTD2692_MODE_DISABLE = 0,
+ KTD2692_MODE_MOVIE,
+ KTD2692_MODE_FLASH,
+};
+
+enum ktd2692_bitset {
+ KTD2692_LOW = 0,
+ KTD2692_HIGH,
+};
+
+struct ktd2692_context {
+ struct led_classdev cdev;
+ u8 mode;
+ int strobe_gpio;
+};
+
+static int ktd2692_brightness_set_gpio(struct ktd2692_context *led)
+{
+ int ret;
+
+ ret = devm_gpio_request_one(led->cdev.dev,
+ led->strobe_gpio, GPIOF_INIT_LOW, "strobe-gpio");
+
+ if (ret)
+ dev_err(led->cdev.dev,
+ "failed to request strobe-gpio %d error %d\n",
+ led->strobe_gpio, ret);
+
+ return ret;
+}
+
+static void ktd2692_expresswire_start(struct ktd2692_context *led)
+{
+ gpio_set_value(led->strobe_gpio, KTD2692_HIGH);
+ udelay(KTD2692_TIME_DATA_START_TIME_US);
+}
+
+static void ktd2692_expresswire_reset(struct ktd2692_context *led)
+{
+ gpio_set_value(led->strobe_gpio, KTD2692_LOW);
+ udelay(KTD2692_TIME_RESET_US);
+}
+
+static void ktd2692_expresswire_end(struct ktd2692_context *led)
+{
+ gpio_set_value(led->strobe_gpio, KTD2692_LOW);
+ udelay(KTD2692_TIME_LOW_END_OF_DATA_US);
+ gpio_set_value(led->strobe_gpio, KTD2692_HIGH);
+ udelay(KTD2692_TIME_HIGH_END_OF_DATA_US);
+}
+
+static void ktd2692_expresswire_set_bit(struct ktd2692_context *led, bool bit)
+{
+ if (bit) {
+ gpio_set_value(led->strobe_gpio, KTD2692_LOW);
+ udelay(KTD2692_TIME_SHORT_BITSET_US);
+ gpio_set_value(led->strobe_gpio, KTD2692_HIGH);
+ udelay(KTD2692_TIME_LONG_BITSET_US);
+ } else {
+ gpio_set_value(led->strobe_gpio, KTD2692_LOW);
+ udelay(KTD2692_TIME_LONG_BITSET_US);
+ gpio_set_value(led->strobe_gpio, KTD2692_HIGH);
+ udelay(KTD2692_TIME_SHORT_BITSET_US);
+ }
+}
+
+static void ktd2692_expresswire_write(struct ktd2692_context *led, u8 value)
+{
+ int i;
+
+ ktd2692_expresswire_start(led);
+ for (i = 7; i >= 0; i--)
+ ktd2692_expresswire_set_bit(led, GET_BIT(i, value));
+ ktd2692_expresswire_end(led);
+}
+
+static void ktd2692_brightness_set(struct led_classdev *led_cdev,
+ enum led_brightness value)
+{
+ u8 mask;
+ int brightness = (int)value;
+ struct ktd2692_context *led =
+ container_of(led_cdev, struct ktd2692_context, cdev);
+
+ if (brightness == LED_OFF) {
+ gpio_set_value(led->strobe_gpio, 0);
+ led->cdev.brightness = brightness;
+ return;
+ }
+
+ if (brightness < 0 || brightness > led->cdev.max_brightness) {
+ dev_err(led_cdev->dev, "Invalid brightness %d\n", brightness);
+ } else {
+ mask = KTD2692_BRIGHTNESS_RANGE_255_TO_8(value);
+ mask |= KTD2692_REG_MOVIE_CURRENT_BASE;
+ ktd2692_expresswire_write(led, mask);
+
+ led->mode = KTD2692_REG_MODE_BASE | KTD2692_MODE_MOVIE;
+ ktd2692_expresswire_write(led, led->mode);
+ led->cdev.brightness = brightness;
+ }
+}
+
+static enum led_brightness ktd2692_brightness_get(struct led_classdev *led_cdev)
+{
+ struct ktd2692_context *led =
+ container_of(led_cdev, struct ktd2692_context, cdev);
+
+ return led->cdev.brightness;
+}
+
+static struct ktd2692_context *ktd2692_parse_dt(struct device *dev)
+{
+ struct device_node *np = dev->of_node;
+ struct ktd2692_context *led;
+
+ led = devm_kzalloc(dev, sizeof(struct ktd2692_context), GFP_KERNEL);
+ if (!led)
+ return ERR_PTR((long)led);
+
+ led->strobe_gpio = of_get_named_gpio(np, "strobe-gpio", 0);
+ if (!gpio_is_valid(led->strobe_gpio)) {
+ dev_err(dev, "no strobe_gpio property found\n");
+ return ERR_PTR(led->strobe_gpio);
+ }
+
+ return led;
+}
+
+static int ktd2692_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct ktd2692_context *led;
+ int ret;
+
+ if (!dev->of_node)
+ return -ENODEV;
+
+ led = ktd2692_parse_dt(dev);
+ if (IS_ERR(led))
+ return PTR_ERR(led);
+
+ led->cdev.name = KTD2692_DEFAULT_NAME;
+ led->cdev.brightness = LED_OFF;
+ led->cdev.max_brightness = LED_FULL;
+ led->cdev.flags |= LED_CORE_SUSPENDRESUME;
+ led->cdev.brightness_set = ktd2692_brightness_set;
+ led->cdev.brightness_get = ktd2692_brightness_get;
+ led->mode = KTD2692_REG_MODE_BASE | KTD2692_MODE_DISABLE;
+
+ platform_set_drvdata(pdev, led);
+
+ ret = led_classdev_register(&pdev->dev, &led->cdev);
+ if (ret) {
+ dev_err(dev, "couldn't register LED %s\n", led->cdev.name);
+ return ret;
+ }
+
+ ret = ktd2692_brightness_set_gpio(led);
+ if (ret) {
+ led_classdev_unregister(&led->cdev);
+ return ret;
+ }
+
+ ktd2692_expresswire_reset(led);
+
+ return ret;
+}
+
+static int ktd2692_remove(struct platform_device *pdev)
+{
+ struct ktd2692_context *led = platform_get_drvdata(pdev);
+
+ led_classdev_unregister(&led->cdev);
+
+ return 0;
+}
+
+static const struct of_device_id ktd2692_match[] = {
+ { .compatible = "kinetic,ktd2692", },
+ { /* sentinel */ },
+};
+
+static struct platform_driver ktd2692_driver = {
+ .driver = {
+ .name = "leds-ktd2692",
+ .of_match_table = ktd2692_match,
+ },
+ .probe = ktd2692_probe,
+ .remove = ktd2692_remove,
+};
+
+module_platform_driver(ktd2692_driver);
+
+MODULE_AUTHOR("Ingi Kim <[email protected]>");
+MODULE_DESCRIPTION("Kinetic KTD2692 LED driver");
+MODULE_LICENSE("GPL v2");
--
1.7.9.5
On 02/27/2015 06:31 AM, Ingi Kim wrote:
> This patch adds a driver to support the ktd2692 flash LEDs.
> ktd2692 can control flash current by ExpressWire interface.
>
> Signed-off-by: Ingi Kim <[email protected]>
> ---
> drivers/leds/Kconfig | 8 ++
> drivers/leds/Makefile | 1 +
> drivers/leds/leds-ktd2692.c | 245 +++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 254 insertions(+)
> create mode 100644 drivers/leds/leds-ktd2692.c
>
(...)
> +static struct ktd2692_context *ktd2692_parse_dt(struct device *dev)
> +{
> + struct device_node *np = dev->of_node;
> + struct ktd2692_context *led;
> +
> + led = devm_kzalloc(dev, sizeof(struct ktd2692_context), GFP_KERNEL);
> + if (!led)
> + return ERR_PTR((long)led);
What about using sizeof(*led) in place of sizeof(struct ktd2692_context)..?
Also the error return for devm_kzalloc() should be -ENOMEM.
> +
> + led->strobe_gpio = of_get_named_gpio(np, "strobe-gpio", 0);
> + if (!gpio_is_valid(led->strobe_gpio)) {
> + dev_err(dev, "no strobe_gpio property found\n");
> + return ERR_PTR(led->strobe_gpio);
> + }
> +
> + return led;
> +}
> +
> +static int ktd2692_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct ktd2692_context *led;
> + int ret;
> +
> + if (!dev->of_node)
> + return -ENODEV;
> +
> + led = ktd2692_parse_dt(dev);
> + if (IS_ERR(led))
> + return PTR_ERR(led);
> +
> + led->cdev.name = KTD2692_DEFAULT_NAME;
> + led->cdev.brightness = LED_OFF;
> + led->cdev.max_brightness = LED_FULL;
> + led->cdev.flags |= LED_CORE_SUSPENDRESUME;
> + led->cdev.brightness_set = ktd2692_brightness_set;
> + led->cdev.brightness_get = ktd2692_brightness_get;
> + led->mode = KTD2692_REG_MODE_BASE | KTD2692_MODE_DISABLE;
> +
> + platform_set_drvdata(pdev, led);
> +
> + ret = led_classdev_register(&pdev->dev, &led->cdev);
> + if (ret) {
> + dev_err(dev, "couldn't register LED %s\n", led->cdev.name);
> + return ret;
> + }
> +
> + ret = ktd2692_brightness_set_gpio(led);
> + if (ret) {
> + led_classdev_unregister(&led->cdev);
> + return ret;
> + }
> +
> + ktd2692_expresswire_reset(led);
> +
> + return ret;
return 0 instead of ret...?
--
Thanks,
Varka Bhadram.
hi
On 2015년 02월 27일 12:36, Varka Bhadram wrote:
> On 02/27/2015 06:31 AM, Ingi Kim wrote:
>> This patch adds a driver to support the ktd2692 flash LEDs.
>> ktd2692 can control flash current by ExpressWire interface.
>>
>> Signed-off-by: Ingi Kim <[email protected]>
>> ---
>> drivers/leds/Kconfig | 8 ++
>> drivers/leds/Makefile | 1 +
>> drivers/leds/leds-ktd2692.c | 245 +++++++++++++++++++++++++++++++++++++++++++
>> 3 files changed, 254 insertions(+)
>> create mode 100644 drivers/leds/leds-ktd2692.c
>>
> (...)
>
>> +static struct ktd2692_context *ktd2692_parse_dt(struct device *dev)
>> +{
>> + struct device_node *np = dev->of_node;
>> + struct ktd2692_context *led;
>> +
>> + led = devm_kzalloc(dev, sizeof(struct ktd2692_context), GFP_KERNEL);
>> + if (!led)
>> + return ERR_PTR((long)led);
>
> What about using sizeof(*led) in place of sizeof(struct ktd2692_context)..?
>
> Also the error return for devm_kzalloc() should be -ENOMEM.
>
Thanks, I'll check and change sizeof() and error return style.
>> +
>> + led->strobe_gpio = of_get_named_gpio(np, "strobe-gpio", 0);
>> + if (!gpio_is_valid(led->strobe_gpio)) {
>> + dev_err(dev, "no strobe_gpio property found\n");
>> + return ERR_PTR(led->strobe_gpio);
>> + }
>> +
>> + return led;
>> +}
>> +
>> +static int ktd2692_probe(struct platform_device *pdev)
>> +{
>> + struct device *dev = &pdev->dev;
>> + struct ktd2692_context *led;
>> + int ret;
>> +
>> + if (!dev->of_node)
>> + return -ENODEV;
>> +
>> + led = ktd2692_parse_dt(dev);
>> + if (IS_ERR(led))
>> + return PTR_ERR(led);
>> +
>> + led->cdev.name = KTD2692_DEFAULT_NAME;
>> + led->cdev.brightness = LED_OFF;
>> + led->cdev.max_brightness = LED_FULL;
>> + led->cdev.flags |= LED_CORE_SUSPENDRESUME;
>> + led->cdev.brightness_set = ktd2692_brightness_set;
>> + led->cdev.brightness_get = ktd2692_brightness_get;
>> + led->mode = KTD2692_REG_MODE_BASE | KTD2692_MODE_DISABLE;
>> +
>> + platform_set_drvdata(pdev, led);
>> +
>> + ret = led_classdev_register(&pdev->dev, &led->cdev);
>> + if (ret) {
>> + dev_err(dev, "couldn't register LED %s\n", led->cdev.name);
>> + return ret;
>> + }
>> +
>> + ret = ktd2692_brightness_set_gpio(led);
>> + if (ret) {
>> + led_classdev_unregister(&led->cdev);
>> + return ret;
>> + }
>> +
>> + ktd2692_expresswire_reset(led);
>> +
>> + return ret;
>
> return 0 instead of ret...?
>
>
>
I'll check and try
Thanks,
Hi Ingi,
On 02/27/2015 02:01 AM, Ingi Kim wrote:
> This patch supports KTD2692 flash LED driver
>
> Ingi Kim (3):
> of: Add vendor prefix for Kinetic technologies
> leds: ktd2692: add device tree bindings for ktd2692
> leds: Add ktd2692 flash LED driver
>
> .../devicetree/bindings/leds/leds-ktd2692.txt | 19 ++
> .../devicetree/bindings/vendor-prefixes.txt | 1 +
> drivers/leds/Kconfig | 8 +
> drivers/leds/Makefile | 1 +
> drivers/leds/leds-ktd2692.c | 245 ++++++++++++++++++++
> 5 files changed, 274 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/leds/leds-ktd2692.txt
> create mode 100644 drivers/leds/leds-ktd2692.c
>
In your device tree binding documentation there is torch-gpio mentioned,
but you seem not to use it in the driver.
We have already LED Flash class (/drivers/leds/led-class-flash.c) for
this type of devices, which handles both torch and flash modes
(flash_strobe sysfs attribute is provided for strobing the flash).
The reference drivers using LED Flash class are still pending [1], but I
think that at least leds-aat1290 driver is almost ready for merging.
It controls very similar device to yours.
Another advantage of using LED Flash class is that it has been designed
to be compatible with Video for Linux 2 subsystem, which will allow for
registering LED Flash class devices as a V4L2 sub-devices.
Adding Sakari.
--
Best Regards,
Jacek Anaszewski
[1] http://www.spinics.net/lists/linux-media/msg86632.html