leds: lm3692x: Support LED sync configuration

The LM36922 has one output but can sync current to 2 LED
strings. The user may only use one sync so the other
syncs need to be disabled.

The LM36923 has 3 LED syncs.

Signed-off-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>

diff --git a/drivers/leds/leds-lm3692x.c b/drivers/leds/leds-lm3692x.c
index 9e6432b..4f413a7 100644 (file)
--- a/drivers/leds/leds-lm3692x.c
+++ b/drivers/leds/leds-lm3692x.c
@@ -15,6 +15,9 @@
 #include <linux/slab.h>
 #include <uapi/linux/uleds.h>
 
+#define LM36922_MODEL  0
+#define LM36923_MODEL  1
+
 #define LM3692X_REV            0x0
 #define LM3692X_RESET          0x1
 #define LM3692X_EN             0x10
@@ -33,6 +36,9 @@
 #define LM3692X_DEVICE_EN      BIT(0)
 #define LM3692X_LED1_EN                BIT(1)
 #define LM3692X_LED2_EN                BIT(2)
+#define LM36923_LED3_EN                BIT(3)
+#define LM3692X_ENABLE_MASK    (LM3692X_DEVICE_EN | LM3692X_LED1_EN | \
+                                LM3692X_LED2_EN | LM36923_LED3_EN)
 
 /* Brightness Control Bits */
 #define LM3692X_BL_ADJ_POL     BIT(0)
@@ -98,6 +104,8 @@
  * @enable_gpio - VDDIO/EN gpio to enable communication interface
  * @regulator - LED supply regulator pointer
  * @label - LED label
+ * @led_enable - LED sync to be enabled
+ * @model_id - Current device model ID enumerated
  */
 struct lm3692x_led {
        struct mutex lock;
@@ -107,6 +115,8 @@ struct lm3692x_led {
        struct gpio_desc *enable_gpio;
        struct regulator *regulator;
        char label[LED_MAX_NAME_SIZE];
+       int led_enable;
+       int model_id;
 };
 
 static const struct reg_default lm3692x_reg_defs[] = {
@@ -189,6 +199,7 @@ out:
 
 static int lm3692x_init(struct lm3692x_led *led)
 {
+       int enable_state;
        int ret;
 
        if (led->regulator) {
@@ -215,9 +226,25 @@ static int lm3692x_init(struct lm3692x_led *led)
 
        /*
         * For glitch free operation, the following data should
-        * only be written while device enable bit is 0
+        * only be written while LEDx enable bits are 0 and the device enable
+        * bit is set to 1.
         * per Section 7.5.14 of the data sheet
         */
+       ret = regmap_write(led->regmap, LM3692X_EN, LM3692X_DEVICE_EN);
+       if (ret)
+               goto out;
+
+       /* Set the brightness to 0 so when enabled the LEDs do not come
+        * on with full brightness.
+        */
+       ret = regmap_write(led->regmap, LM3692X_BRT_MSB, 0);
+       if (ret)
+               goto out;
+
+       ret = regmap_write(led->regmap, LM3692X_BRT_LSB, 0);
+       if (ret)
+               goto out;
+
        ret = regmap_write(led->regmap, LM3692X_PWM_CTRL,
                LM3692X_PWM_FILTER_100 | LM3692X_PWM_SAMP_24MHZ);
        if (ret)
@@ -247,6 +274,38 @@ static int lm3692x_init(struct lm3692x_led *led)
        if (ret)
                goto out;
 
+       switch (led->led_enable) {
+       case 0:
+       default:
+               if (led->model_id == LM36923_MODEL)
+                       enable_state = LM3692X_LED1_EN | LM3692X_LED2_EN |
+                              LM36923_LED3_EN;
+               else
+                       enable_state = LM3692X_LED1_EN | LM3692X_LED2_EN;
+
+               break;
+       case 1:
+               enable_state = LM3692X_LED1_EN;
+               break;
+       case 2:
+               enable_state = LM3692X_LED2_EN;
+               break;
+
+       case 3:
+               if (led->model_id == LM36923_MODEL) {
+                       enable_state = LM36923_LED3_EN;
+                       break;
+               }
+
+               ret = -EINVAL;
+               dev_err(&led->client->dev,
+                       "LED3 sync not available on this device\n");
+               goto out;
+       }
+
+       ret = regmap_update_bits(led->regmap, LM3692X_EN, LM3692X_ENABLE_MASK,
+                                enable_state | LM3692X_DEVICE_EN);
+
        return ret;
 out:
        dev_err(&led->client->dev, "Fail writing initialization values\n");
@@ -263,55 +322,29 @@ out:
 
        return ret;
 }
-
-static int lm3692x_probe(struct i2c_client *client,
-                       const struct i2c_device_id *id)
+static int lm3692x_probe_dt(struct lm3692x_led *led)
 {
        struct fwnode_handle *child = NULL;
-       struct lm3692x_led *led;
        const char *name;
        int ret;
 
-       led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL);
-       if (!led)
-               return -ENOMEM;
-
-       led->enable_gpio = devm_gpiod_get_optional(&client->dev,
+       led->enable_gpio = devm_gpiod_get_optional(&led->client->dev,
                                                   "enable", GPIOD_OUT_LOW);
        if (IS_ERR(led->enable_gpio)) {
                ret = PTR_ERR(led->enable_gpio);
-               dev_err(&client->dev, "Failed to get enable gpio: %d\n", ret);
+               dev_err(&led->client->dev, "Failed to get enable gpio: %d\n",
+                       ret);
                return ret;
        }
 
-       led->regulator = devm_regulator_get(&client->dev, "vled");
+       led->regulator = devm_regulator_get(&led->client->dev, "vled");
        if (IS_ERR(led->regulator))
                led->regulator = NULL;
 
-       led->client = client;
-       led->led_dev.name = led->label;
-       led->led_dev.brightness_set_blocking = lm3692x_brightness_set;
-
-       mutex_init(&led->lock);
-
-       i2c_set_clientdata(client, led);
-
-       led->regmap = devm_regmap_init_i2c(client, &lm3692x_regmap_config);
-       if (IS_ERR(led->regmap)) {
-               ret = PTR_ERR(led->regmap);
-               dev_err(&client->dev, "Failed to allocate register map: %d\n",
-                       ret);
-               return ret;
-       }
-
-       ret = lm3692x_init(led);
-       if (ret)
-               return ret;
-
        child = device_get_next_child_node(&led->client->dev, child);
        if (!child) {
                dev_err(&led->client->dev, "No LED Child node\n");
-               return ret;
+               return -ENODEV;
        }
 
        fwnode_property_read_string(child, "linux,default-trigger",
@@ -325,14 +358,57 @@ static int lm3692x_probe(struct i2c_client *client,
                snprintf(led->label, sizeof(led->label),
                         "%s:%s", led->client->name, name);
 
-       led->led_dev.dev->of_node = to_of_node(child);
+       ret = fwnode_property_read_u32(child, "reg", &led->led_enable);
+       if (ret) {
+               dev_err(&led->client->dev, "reg DT property missing\n");
+               return ret;
+       }
+
+       led->led_dev.name = led->label;
 
-       ret = devm_led_classdev_register(&client->dev, &led->led_dev);
+       ret = devm_led_classdev_register(&led->client->dev, &led->led_dev);
        if (ret) {
-               dev_err(&client->dev, "led register err: %d\n", ret);
+               dev_err(&led->client->dev, "led register err: %d\n", ret);
+               return ret;
+       }
+
+       led->led_dev.dev->of_node = to_of_node(child);
+
+       return 0;
+}
+
+static int lm3692x_probe(struct i2c_client *client,
+                       const struct i2c_device_id *id)
+{
+       struct lm3692x_led *led;
+       int ret;
+
+       led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL);
+       if (!led)
+               return -ENOMEM;
+
+       mutex_init(&led->lock);
+       led->client = client;
+       led->led_dev.brightness_set_blocking = lm3692x_brightness_set;
+       led->model_id = id->driver_data;
+       i2c_set_clientdata(client, led);
+
+       led->regmap = devm_regmap_init_i2c(client, &lm3692x_regmap_config);
+       if (IS_ERR(led->regmap)) {
+               ret = PTR_ERR(led->regmap);
+               dev_err(&client->dev, "Failed to allocate register map: %d\n",
+                       ret);
                return ret;
        }
 
+       ret = lm3692x_probe_dt(led);
+       if (ret)
+               return ret;
+
+       ret = lm3692x_init(led);
+       if (ret)
+               return ret;
+
        return 0;
 }
 
@@ -341,6 +417,12 @@ static int lm3692x_remove(struct i2c_client *client)
        struct lm3692x_led *led = i2c_get_clientdata(client);
        int ret;
 
+       ret = regmap_update_bits(led->regmap, LM3692X_EN, LM3692X_DEVICE_EN, 0);
+       if (ret) {
+               dev_err(&led->client->dev, "Failed to disable regulator\n");
+               return ret;
+       }
+
        if (led->enable_gpio)
                gpiod_direction_output(led->enable_gpio, 0);
 
@@ -357,8 +439,8 @@ static int lm3692x_remove(struct i2c_client *client)
 }
 
 static const struct i2c_device_id lm3692x_id[] = {
-       { "lm36922", 0 },
-       { "lm36923", 1 },
+       { "lm36922", LM36922_MODEL },
+       { "lm36923", LM36923_MODEL },
        { }
 };
 MODULE_DEVICE_TABLE(i2c, lm3692x_id);