Merge branches 'ib-qcom-leds-6.9' and 'ib-leds-backlight-6.9' into ibs-for-leds-merged

8 files changed, 244 insertions, 90 deletions

diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index d721b254e1e4..64bb2de237e9 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -186,6 +186,10 @@ config LEDS_EL15203000
 	  To compile this driver as a module, choose M here: the module
 	  will be called leds-el15203000.
 
+config LEDS_EXPRESSWIRE
+	bool
+	depends on GPIOLIB
+
 config LEDS_TURRIS_OMNIA
 	tristate "LED support for CZ.NIC's Turris Omnia"
 	depends on LEDS_CLASS_MULTICOLOR
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index ce07dc295ff0..effdfc6f1e95 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -91,6 +91,9 @@ obj-$(CONFIG_LEDS_WM831X_STATUS)	+= leds-wm831x-status.o
 obj-$(CONFIG_LEDS_WM8350)		+= leds-wm8350.o
 obj-$(CONFIG_LEDS_WRAP)			+= leds-wrap.o
 
+# Kinetic ExpressWire Protocol
+obj-$(CONFIG_LEDS_EXPRESSWIRE)		+= leds-expresswire.o
+
 # LED SPI Drivers
 obj-$(CONFIG_LEDS_CR0014114)		+= leds-cr0014114.o
 obj-$(CONFIG_LEDS_DAC124S085)		+= leds-dac124s085.o
diff --git a/drivers/leds/flash/Kconfig b/drivers/leds/flash/Kconfig
index 4e08dbc05709..24722d581369 100644
--- a/drivers/leds/flash/Kconfig
+++ b/drivers/leds/flash/Kconfig
@@ -23,7 +23,8 @@ config LEDS_AS3645A
 config LEDS_KTD2692
 	tristate "LED support for Kinetic KTD2692 flash LED controller"
 	depends on OF
-	depends on GPIOLIB || COMPILE_TEST
+	depends on GPIOLIB
+	select LEDS_EXPRESSWIRE
 	help
 	  This option enables support for Kinetic KTD2692 LED flash connected
 	  through ExpressWire interface.
diff --git a/drivers/leds/flash/leds-ktd2692.c b/drivers/leds/flash/leds-ktd2692.c
index 598eee5daa52..7bb0aa2753e3 100644
--- a/drivers/leds/flash/leds-ktd2692.c
+++ b/drivers/leds/flash/leds-ktd2692.c
@@ -6,9 +6,9 @@
  * Ingi Kim <ingi2.kim@samsung.com>
  */
 
-#include <linux/delay.h>
 #include <linux/err.h>
 #include <linux/gpio/consumer.h>
+#include <linux/leds-expresswire.h>
 #include <linux/led-class-flash.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
@@ -37,22 +37,9 @@
 #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
 
-enum ktd2692_bitset {
-	KTD2692_LOW = 0,
-	KTD2692_HIGH,
-};
-
 /* Movie / Flash Mode Control */
 enum ktd2692_led_mode {
 	KTD2692_MODE_DISABLE = 0,	/* default */
@@ -71,7 +58,19 @@ struct ktd2692_led_config_data {
 	enum led_brightness max_brightness;
 };
 
+const struct expresswire_timing ktd2692_timing = {
+	.poweroff_us = 700,
+	.data_start_us = 10,
+	.end_of_data_low_us = 10,
+	.end_of_data_high_us = 350,
+	.short_bitset_us = 4,
+	.long_bitset_us = 12
+};
+
 struct ktd2692_context {
+	/* Common ExpressWire properties (ctrl GPIO and timing) */
+	struct expresswire_common_props props;
+
 	/* Related LED Flash class device */
 	struct led_classdev_flash fled_cdev;
 
@@ -80,7 +79,6 @@ struct ktd2692_context {
 	struct regulator *regulator;
 
 	struct gpio_desc *aux_gpio;
-	struct gpio_desc *ctrl_gpio;
 
 	enum ktd2692_led_mode mode;
 	enum led_brightness torch_brightness;
@@ -92,67 +90,6 @@ static struct ktd2692_context *fled_cdev_to_led(
 	return container_of(fled_cdev, struct ktd2692_context, fled_cdev);
 }
 
-static void ktd2692_expresswire_start(struct ktd2692_context *led)
-{
-	gpiod_direction_output(led->ctrl_gpio, KTD2692_HIGH);
-	udelay(KTD2692_TIME_DATA_START_TIME_US);
-}
-
-static void ktd2692_expresswire_reset(struct ktd2692_context *led)
-{
-	gpiod_direction_output(led->ctrl_gpio, KTD2692_LOW);
-	udelay(KTD2692_TIME_RESET_US);
-}
-
-static void ktd2692_expresswire_end(struct ktd2692_context *led)
-{
-	gpiod_direction_output(led->ctrl_gpio, KTD2692_LOW);
-	udelay(KTD2692_TIME_LOW_END_OF_DATA_US);
-	gpiod_direction_output(led->ctrl_gpio, KTD2692_HIGH);
-	udelay(KTD2692_TIME_HIGH_END_OF_DATA_US);
-}
-
-static void ktd2692_expresswire_set_bit(struct ktd2692_context *led, bool bit)
-{
-	/*
-	 * The Low Bit(0) and High Bit(1) is based on a time detection
-	 * algorithm between time low and time high
-	 * Time_(L_LB) : Low time of the Low Bit(0)
-	 * Time_(H_LB) : High time of the LOW Bit(0)
-	 * Time_(L_HB) : Low time of the High Bit(1)
-	 * Time_(H_HB) : High time of the High Bit(1)
-	 *
-	 * It can be simplified to:
-	 * Low Bit(0) : 2 * Time_(H_LB) < Time_(L_LB)
-	 * High Bit(1) : 2 * Time_(L_HB) < Time_(H_HB)
-	 * HIGH  ___           ____    _..     _________    ___
-	 *          |_________|    |_..  |____|         |__|
-	 * LOW        <L_LB>  <H_LB>     <L_HB>  <H_HB>
-	 *          [  Low Bit (0) ]     [  High Bit(1) ]
-	 */
-	if (bit) {
-		gpiod_direction_output(led->ctrl_gpio, KTD2692_LOW);
-		udelay(KTD2692_TIME_SHORT_BITSET_US);
-		gpiod_direction_output(led->ctrl_gpio, KTD2692_HIGH);
-		udelay(KTD2692_TIME_LONG_BITSET_US);
-	} else {
-		gpiod_direction_output(led->ctrl_gpio, KTD2692_LOW);
-		udelay(KTD2692_TIME_LONG_BITSET_US);
-		gpiod_direction_output(led->ctrl_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, value & BIT(i));
-	ktd2692_expresswire_end(led);
-}
-
 static int ktd2692_led_brightness_set(struct led_classdev *led_cdev,
 				       enum led_brightness brightness)
 {
@@ -163,14 +100,14 @@ static int ktd2692_led_brightness_set(struct led_classdev *led_cdev,
 
 	if (brightness == LED_OFF) {
 		led->mode = KTD2692_MODE_DISABLE;
-		gpiod_direction_output(led->aux_gpio, KTD2692_LOW);
+		gpiod_direction_output(led->aux_gpio, 0);
 	} else {
-		ktd2692_expresswire_write(led, brightness |
+		expresswire_write_u8(&led->props, brightness |
 					KTD2692_REG_MOVIE_CURRENT_BASE);
 		led->mode = KTD2692_MODE_MOVIE;
 	}
 
-	ktd2692_expresswire_write(led, led->mode | KTD2692_REG_MODE_BASE);
+	expresswire_write_u8(&led->props, led->mode | KTD2692_REG_MODE_BASE);
 	mutex_unlock(&led->lock);
 
 	return 0;
@@ -187,17 +124,17 @@ static int ktd2692_led_flash_strobe_set(struct led_classdev_flash *fled_cdev,
 
 	if (state) {
 		flash_tm_reg = GET_TIMEOUT_OFFSET(timeout->val, timeout->step);
-		ktd2692_expresswire_write(led, flash_tm_reg
+		expresswire_write_u8(&led->props, flash_tm_reg
 				| KTD2692_REG_FLASH_TIMEOUT_BASE);
 
 		led->mode = KTD2692_MODE_FLASH;
-		gpiod_direction_output(led->aux_gpio, KTD2692_HIGH);
+		gpiod_direction_output(led->aux_gpio, 1);
 	} else {
 		led->mode = KTD2692_MODE_DISABLE;
-		gpiod_direction_output(led->aux_gpio, KTD2692_LOW);
+		gpiod_direction_output(led->aux_gpio, 0);
 	}
 
-	ktd2692_expresswire_write(led, led->mode | KTD2692_REG_MODE_BASE);
+	expresswire_write_u8(&led->props, led->mode | KTD2692_REG_MODE_BASE);
 
 	fled_cdev->led_cdev.brightness = LED_OFF;
 	led->mode = KTD2692_MODE_DISABLE;
@@ -247,12 +184,12 @@ static void ktd2692_init_flash_timeout(struct led_classdev_flash *fled_cdev,
 static void ktd2692_setup(struct ktd2692_context *led)
 {
 	led->mode = KTD2692_MODE_DISABLE;
-	ktd2692_expresswire_reset(led);
-	gpiod_direction_output(led->aux_gpio, KTD2692_LOW);
+	expresswire_power_off(&led->props);
+	gpiod_direction_output(led->aux_gpio, 0);
 
-	ktd2692_expresswire_write(led, (KTD2692_MM_MIN_CURR_THRESHOLD_SCALE - 1)
+	expresswire_write_u8(&led->props, (KTD2692_MM_MIN_CURR_THRESHOLD_SCALE - 1)
 				 | KTD2692_REG_MM_MIN_CURR_THRESHOLD_BASE);
-	ktd2692_expresswire_write(led, KTD2692_FLASH_MODE_CURR_PERCENT(45)
+	expresswire_write_u8(&led->props, KTD2692_FLASH_MODE_CURR_PERCENT(45)
 				 | KTD2692_REG_FLASH_CURRENT_BASE);
 }
 
@@ -277,8 +214,8 @@ static int ktd2692_parse_dt(struct ktd2692_context *led, struct device *dev,
 	if (!np)
 		return -ENXIO;
 
-	led->ctrl_gpio = devm_gpiod_get(dev, "ctrl", GPIOD_ASIS);
-	ret = PTR_ERR_OR_ZERO(led->ctrl_gpio);
+	led->props.ctrl_gpio = devm_gpiod_get(dev, "ctrl", GPIOD_ASIS);
+	ret = PTR_ERR_OR_ZERO(led->props.ctrl_gpio);
 	if (ret)
 		return dev_err_probe(dev, ret, "cannot get ctrl-gpios\n");
 
@@ -412,6 +349,7 @@ static struct platform_driver ktd2692_driver = {
 
 module_platform_driver(ktd2692_driver);
 
+MODULE_IMPORT_NS(EXPRESSWIRE);
 MODULE_AUTHOR("Ingi Kim <ingi2.kim@samsung.com>");
 MODULE_DESCRIPTION("Kinetic KTD2692 LED driver");
 MODULE_LICENSE("GPL v2");
diff --git a/drivers/leds/leds-expresswire.c b/drivers/leds/leds-expresswire.c
new file mode 100644
index 000000000000..e4937a8e0f44
--- /dev/null
+++ b/drivers/leds/leds-expresswire.c
@@ -0,0 +1,72 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Shared library for Kinetic's ExpressWire protocol.
+ * This protocol works by pulsing the ExpressWire IC's control GPIO.
+ * ktd2692 and ktd2801 are known to use this protocol.
+ */
+
+#include <linux/bits.h>
+#include <linux/delay.h>
+#include <linux/export.h>
+#include <linux/gpio/consumer.h>
+#include <linux/types.h>
+
+#include <linux/leds-expresswire.h>
+
+void expresswire_power_off(struct expresswire_common_props *props)
+{
+	gpiod_set_value_cansleep(props->ctrl_gpio, 0);
+	usleep_range(props->timing.poweroff_us, props->timing.poweroff_us * 2);
+}
+EXPORT_SYMBOL_NS_GPL(expresswire_power_off, EXPRESSWIRE);
+
+void expresswire_enable(struct expresswire_common_props *props)
+{
+	gpiod_set_value(props->ctrl_gpio, 1);
+	udelay(props->timing.detect_delay_us);
+	gpiod_set_value(props->ctrl_gpio, 0);
+	udelay(props->timing.detect_us);
+	gpiod_set_value(props->ctrl_gpio, 1);
+}
+EXPORT_SYMBOL_NS_GPL(expresswire_enable, EXPRESSWIRE);
+
+void expresswire_start(struct expresswire_common_props *props)
+{
+	gpiod_set_value(props->ctrl_gpio, 1);
+	udelay(props->timing.data_start_us);
+}
+EXPORT_SYMBOL_NS_GPL(expresswire_start, EXPRESSWIRE);
+
+void expresswire_end(struct expresswire_common_props *props)
+{
+	gpiod_set_value(props->ctrl_gpio, 0);
+	udelay(props->timing.end_of_data_low_us);
+	gpiod_set_value(props->ctrl_gpio, 1);
+	udelay(props->timing.end_of_data_high_us);
+}
+EXPORT_SYMBOL_NS_GPL(expresswire_end, EXPRESSWIRE);
+
+void expresswire_set_bit(struct expresswire_common_props *props, bool bit)
+{
+	if (bit) {
+		gpiod_set_value(props->ctrl_gpio, 0);
+		udelay(props->timing.short_bitset_us);
+		gpiod_set_value(props->ctrl_gpio, 1);
+		udelay(props->timing.long_bitset_us);
+	} else {
+		gpiod_set_value(props->ctrl_gpio, 0);
+		udelay(props->timing.long_bitset_us);
+		gpiod_set_value(props->ctrl_gpio, 1);
+		udelay(props->timing.short_bitset_us);
+	}
+}
+EXPORT_SYMBOL_NS_GPL(expresswire_set_bit, EXPRESSWIRE);
+
+void expresswire_write_u8(struct expresswire_common_props *props, u8 val)
+{
+	expresswire_start(props);
+	for (int i = 7; i >= 0; i--)
+		expresswire_set_bit(props, val & BIT(i));
+	expresswire_end(props);
+}
+EXPORT_SYMBOL_NS_GPL(expresswire_write_u8, EXPRESSWIRE);
diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
index ea2d0d69bd8c..230bca07b09d 100644
--- a/drivers/video/backlight/Kconfig
+++ b/drivers/video/backlight/Kconfig
@@ -183,6 +183,13 @@ config BACKLIGHT_KTD253
 	  which is a 1-wire GPIO-controlled backlight found in some mobile
 	  phones.
 
+config BACKLIGHT_KTD2801
+	tristate "Backlight Driver for Kinetic KTD2801"
+	select LEDS_EXPRESSWIRE
+	help
+	  Say Y to enable the backlight driver for the Kinetic KTD2801 1-wire
+	  GPIO-controlled backlight found in Samsung Galaxy Core Prime VE LTE.
+
 config BACKLIGHT_KTZ8866
 	tristate "Backlight Driver for Kinetic KTZ8866"
 	depends on I2C
diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile
index 06966cb20459..8d2cb252042d 100644
--- a/drivers/video/backlight/Makefile
+++ b/drivers/video/backlight/Makefile
@@ -34,6 +34,7 @@ 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-$(CONFIG_BACKLIGHT_KTD2801)		+= ktd2801-backlight.o
 obj-$(CONFIG_BACKLIGHT_KTZ8866)		+= ktz8866.o
 obj-$(CONFIG_BACKLIGHT_LM3533)		+= lm3533_bl.o
 obj-$(CONFIG_BACKLIGHT_LM3630A)		+= lm3630a_bl.o
diff --git a/drivers/video/backlight/ktd2801-backlight.c b/drivers/video/backlight/ktd2801-backlight.c
new file mode 100644
index 000000000000..d295c2766025
--- /dev/null
+++ b/drivers/video/backlight/ktd2801-backlight.c
@@ -0,0 +1,128 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Datasheet:
+ * https://www.kinet-ic.com/uploads/web/KTD2801/KTD2801-04b.pdf
+ */
+#include <linux/backlight.h>
+#include <linux/gpio/consumer.h>
+#include <linux/leds-expresswire.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+
+#define KTD2801_DEFAULT_BRIGHTNESS	100
+#define KTD2801_MAX_BRIGHTNESS		255
+
+/* These values have been extracted from Samsung's driver. */
+static const struct expresswire_timing ktd2801_timing = {
+	.poweroff_us = 2600,
+	.detect_delay_us = 150,
+	.detect_us = 270,
+	.data_start_us = 5,
+	.short_bitset_us = 5,
+	.long_bitset_us = 15,
+	.end_of_data_low_us = 10,
+	.end_of_data_high_us = 350
+};
+
+struct ktd2801_backlight {
+	struct expresswire_common_props props;
+	struct backlight_device *bd;
+	bool was_on;
+};
+
+static int ktd2801_update_status(struct backlight_device *bd)
+{
+	struct ktd2801_backlight *ktd2801 = bl_get_data(bd);
+	u8 brightness = (u8) backlight_get_brightness(bd);
+
+	if (backlight_is_blank(bd)) {
+		expresswire_power_off(&ktd2801->props);
+		ktd2801->was_on = false;
+		return 0;
+	}
+
+	if (!ktd2801->was_on) {
+		expresswire_enable(&ktd2801->props);
+		ktd2801->was_on = true;
+	}
+
+	expresswire_write_u8(&ktd2801->props, brightness);
+
+	return 0;
+}
+
+static const struct backlight_ops ktd2801_backlight_ops = {
+	.update_status = ktd2801_update_status,
+};
+
+static int ktd2801_backlight_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct backlight_device *bd;
+	struct ktd2801_backlight *ktd2801;
+	u32 brightness, max_brightness;
+	int ret;
+
+	ktd2801 = devm_kzalloc(dev, sizeof(*ktd2801), GFP_KERNEL);
+	if (!ktd2801)
+		return -ENOMEM;
+	ktd2801->was_on = true;
+	ktd2801->props.timing = ktd2801_timing;
+
+	ret = device_property_read_u32(dev, "max-brightness", &max_brightness);
+	if (ret)
+		max_brightness = KTD2801_MAX_BRIGHTNESS;
+	if (max_brightness > KTD2801_MAX_BRIGHTNESS) {
+		dev_err(dev, "illegal max brightness specified\n");
+		max_brightness = KTD2801_MAX_BRIGHTNESS;
+	}
+
+	ret = device_property_read_u32(dev, "default-brightness", &brightness);
+	if (ret)
+		brightness = KTD2801_DEFAULT_BRIGHTNESS;
+	if (brightness > max_brightness) {
+		dev_err(dev, "default brightness exceeds max\n");
+		brightness = max_brightness;
+	}
+
+	ktd2801->props.ctrl_gpio = devm_gpiod_get(dev, "ctrl", GPIOD_OUT_HIGH);
+	if (IS_ERR(ktd2801->props.ctrl_gpio))
+		return dev_err_probe(dev, PTR_ERR(ktd2801->props.ctrl_gpio),
+				"failed to get backlight GPIO");
+	gpiod_set_consumer_name(ktd2801->props.ctrl_gpio, dev_name(dev));
+
+	bd = devm_backlight_device_register(dev, dev_name(dev), dev, ktd2801,
+			&ktd2801_backlight_ops, NULL);
+	if (IS_ERR(bd))
+		return dev_err_probe(dev, PTR_ERR(bd),
+				"failed to register backlight");
+
+	bd->props.max_brightness = max_brightness;
+	bd->props.brightness = brightness;
+
+	ktd2801->bd = bd;
+	platform_set_drvdata(pdev, bd);
+	backlight_update_status(bd);
+
+	return 0;
+}
+
+static const struct of_device_id ktd2801_of_match[] = {
+	{ .compatible = "kinetic,ktd2801" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, ktd2801_of_match);
+
+static struct platform_driver ktd2801_backlight_driver = {
+	.driver = {
+		.name = "ktd2801-backlight",
+		.of_match_table = ktd2801_of_match,
+	},
+	.probe = ktd2801_backlight_probe,
+};
+module_platform_driver(ktd2801_backlight_driver);
+
+MODULE_IMPORT_NS(EXPRESSWIRE);
+MODULE_AUTHOR("Duje Mihanović <duje.mihanovic@skole.hr>");
+MODULE_DESCRIPTION("Kinetic KTD2801 Backlight Driver");
+MODULE_LICENSE("GPL");