[PATCH v2 3/3] leds: aat1290: Add support for AAT1270 Current Regulator for Flash LEDs

[Svyatoslav Ryhel <clamor95@gmail.com>]

The AAT1270 is quite similar to the AAT1290, but it does not support the
Advanced Simple Serial Control (AS2C) used in the AAT1290. The AAT1270
uses an earlier version of AS2C, namely Simple Serial Control, which lacks
address-sending capabilities.

Differentiate the chips by using a description structure with a flag to
indicate if AS2C is supported, Maximum Movie to Flash Mode Current ratio
and if flash timeout is fixed by the hardware.

Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
---
 drivers/leds/flash/leds-aat1290.c | 91 +++++++++++++++++++++++--------
 1 file changed, 67 insertions(+), 24 deletions(-)

diff --git a/drivers/leds/flash/leds-aat1290.c b/drivers/leds/flash/leds-aat1290.c
index 4bde0b07fe785..cc1771438510d 100644
--- a/drivers/leds/flash/leds-aat1290.c
+++ b/drivers/leds/flash/leds-aat1290.c
@@ -33,8 +33,8 @@
 #define AAT1290_MM_CURRENT_RATIO_ADDR	20
 #define AAT1290_MM_TO_FL_1_92		1
 
-#define AAT1290_MM_TO_FL_RATIO		1000 / 1920
-#define AAT1290_MAX_MM_CURRENT(fl_max)	(fl_max * AAT1290_MM_TO_FL_RATIO)
+#define AAT1270_MM_TO_FL_RATIO		7300
+#define AAT1290_MM_TO_FL_RATIO		1920
 
 #define AAT1290_LATCH_TIME_MIN_US	500
 #define AAT1290_LATCH_TIME_MAX_US	1000
@@ -43,9 +43,6 @@
 #define AAT1290_FLASH_TM_NUM_LEVELS	16
 #define AAT1290_MM_CURRENT_SCALE_SIZE	15
 
-#define AAT1290_NAME			"aat1290"
-
-
 struct aat1290_led_config_data {
 	/* maximum LED current in movie mode */
 	u32 max_mm_current;
@@ -59,6 +56,17 @@ struct aat1290_led_config_data {
 	enum led_brightness max_brightness;
 };
 
+struct aat1290_led_chip_info {
+	/* led controller name */
+	const char *name;
+	/* Maximum Movie to Flash Mode Current Ratio with 1000 presision */
+	u32 mm_to_fl_ratio;
+	/* Advanced Simple Serial Control support */
+	bool as2c;
+	/* Flash timeout is fixed by the hardware */
+	bool fixed_timeout;
+};
+
 struct aat1290_led {
 	/* platform device data */
 	struct platform_device *pdev;
@@ -74,6 +82,10 @@ struct aat1290_led {
 	struct gpio_desc *gpio_fl_en;
 	/* EN|SET pin  */
 	struct gpio_desc *gpio_en_set;
+
+	/* led controller description */
+	const struct aat1290_led_chip_info *info;
+
 	/* movie mode current scale */
 	int *mm_current_scale;
 	/* device mode */
@@ -101,15 +113,17 @@ static void aat1290_as2cwire_write(struct aat1290_led *led, int addr, int value)
 
 	udelay(AAT1290_FLEN_OFF_DELAY_TIME_US);
 
-	/* write address */
-	for (i = 0; i < addr; ++i) {
-		udelay(AAT1290_EN_SET_TICK_TIME_US);
-		gpiod_direction_output(led->gpio_en_set, 0);
-		udelay(AAT1290_EN_SET_TICK_TIME_US);
-		gpiod_direction_output(led->gpio_en_set, 1);
-	}
+	if (led->info->as2c) {
+		/* write address */
+		for (i = 0; i < addr; ++i) {
+			udelay(AAT1290_EN_SET_TICK_TIME_US);
+			gpiod_direction_output(led->gpio_en_set, 0);
+			udelay(AAT1290_EN_SET_TICK_TIME_US);
+			gpiod_direction_output(led->gpio_en_set, 1);
+		}
 
-	usleep_range(AAT1290_LATCH_TIME_MIN_US, AAT1290_LATCH_TIME_MAX_US);
+		usleep_range(AAT1290_LATCH_TIME_MIN_US, AAT1290_LATCH_TIME_MAX_US);
+	}
 
 	/* write data */
 	for (i = 0; i < value; ++i) {
@@ -150,16 +164,18 @@ static int aat1290_led_brightness_set(struct led_classdev *led_cdev,
 		led->movie_mode = false;
 	} else {
 		if (!led->movie_mode) {
-			aat1290_as2cwire_write(led,
-				AAT1290_MM_CURRENT_RATIO_ADDR,
-				AAT1290_MM_TO_FL_1_92);
+			if (led->info->as2c)
+				aat1290_as2cwire_write(led,
+					AAT1290_MM_CURRENT_RATIO_ADDR,
+					AAT1290_MM_TO_FL_1_92);
 			led->movie_mode = true;
 		}
 
 		aat1290_as2cwire_write(led, AAT1290_MOVIE_MODE_CURRENT_ADDR,
 				AAT1290_MAX_MM_CURR_PERCENT_0 - brightness);
-		aat1290_as2cwire_write(led, AAT1290_MOVIE_MODE_CONFIG_ADDR,
-				AAT1290_MOVIE_MODE_ON);
+		if (led->info->as2c)
+			aat1290_as2cwire_write(led, AAT1290_MOVIE_MODE_CONFIG_ADDR,
+					       AAT1290_MOVIE_MODE_ON);
 	}
 
 	mutex_unlock(&led->lock);
@@ -178,7 +194,8 @@ static int aat1290_led_flash_strobe_set(struct led_classdev_flash *fled_cdev,
 	mutex_lock(&led->lock);
 
 	if (state) {
-		aat1290_set_flash_safety_timer(led, timeout->val);
+		if (!led->info->fixed_timeout)
+			aat1290_set_flash_safety_timer(led, timeout->val);
 		gpiod_direction_output(led->gpio_fl_en, 1);
 	} else {
 		gpiod_direction_output(led->gpio_fl_en, 0);
@@ -308,8 +325,10 @@ static int init_mm_current_scale(struct aat1290_led *led,
 		20, 22, 25, 28, 32, 36, 40, 45, 50, 56,
 		63, 71, 79, 89, 100
 	};
-	int i, max_mm_current =
-			AAT1290_MAX_MM_CURRENT(cfg->max_flash_current);
+	int i, max_mm_current;
+
+	max_mm_current = mult_frac(cfg->max_flash_current, 1000,
+				   led->info->mm_to_fl_ratio);
 
 	led->mm_current_scale = devm_kcalloc(&led->pdev->dev,
 					ARRAY_SIZE(max_mm_current_percent),
@@ -360,7 +379,12 @@ static void aat1290_init_flash_timeout(struct aat1290_led *led,
 
 	/* Init flash timeout setting */
 	setting = &fled_cdev->timeout;
-	setting->min = cfg->max_flash_tm / AAT1290_FLASH_TM_NUM_LEVELS;
+
+	if (!led->info->fixed_timeout)
+		setting->min = cfg->max_flash_tm / AAT1290_FLASH_TM_NUM_LEVELS;
+	else
+		setting->min = cfg->max_flash_tm;
+
 	setting->max = cfg->max_flash_tm;
 	setting->step = setting->min;
 	setting->val = setting->max;
@@ -476,6 +500,10 @@ static int aat1290_led_probe(struct platform_device *pdev)
 	fled_cdev->ops = &flash_ops;
 	led_cdev = &fled_cdev->led_cdev;
 
+	led->info = device_get_match_data(dev);
+	if (!led->info)
+		return -ENODEV;
+
 	ret = aat1290_led_get_configuration(led, &led_cfg, &sub_node);
 	if (ret < 0)
 		return ret;
@@ -490,7 +518,7 @@ static int aat1290_led_probe(struct platform_device *pdev)
 	aat1290_init_flash_timeout(led, &led_cfg);
 
 	init_data.fwnode = of_fwnode_handle(sub_node);
-	init_data.devicename = AAT1290_NAME;
+	init_data.devicename = led->info->name;
 
 	/* Register LED Flash class device */
 	ret = led_classdev_flash_register_ext(&pdev->dev, fled_cdev,
@@ -529,8 +557,23 @@ static void aat1290_led_remove(struct platform_device *pdev)
 	mutex_destroy(&led->lock);
 }
 
+static const struct aat1290_led_chip_info aat1290_info = {
+	.name = "aat1290",
+	.mm_to_fl_ratio = AAT1290_MM_TO_FL_RATIO,
+	.as2c = true,
+	.fixed_timeout = false,
+};
+
+static const struct aat1290_led_chip_info aat1270_info = {
+	.name = "aat1270",
+	.mm_to_fl_ratio = AAT1270_MM_TO_FL_RATIO,
+	.as2c = false,
+	.fixed_timeout = true,
+};
+
 static const struct of_device_id aat1290_led_dt_match[] = {
-	{ .compatible = "skyworks,aat1290" },
+	{ .compatible = "skyworks,aat1290", .data = &aat1290_info },
+	{ .compatible = "skyworks,aat1270", .data = &aat1270_info },
 	{},
 };
 MODULE_DEVICE_TABLE(of, aat1290_led_dt_match);
-- 
2.53.0