led: implement LED activity API

Implement LED activity API similar to BOOT LED API.

Usual activity might be a file transfer with TFTP, a flash write...

User of this API will call led_activity_on/off/blink() to signal these
kind of activity.

New Kconfig is implemented similar to BOOT LED, LED_ACTIVITY to
enable support for it.

It's introduced a new /options/u-boot property "activity-led" and
"activity-led-period" to define the activity LED label and the
default period when the activity LED is set to blink mode.

If "activity-led-period" is not defined, the value of 250 (ms) is
used by default.

If CONFIG_LED_BLINK or CONFIG_LED_SW_BLINK is not enabled,
led_boot_blink call will fallback to simple LED ON.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

drivers/led/Kconfig

@@ -20,6 +20,19 @@ config LED_BOOT
 
 	  [1] dtschema/schemas/options/u-boot.yaml
 
+config LED_ACTIVITY
+	bool "Enable LED activity support"
+	help
+	  Enable LED activity support.
+
+	  LED activity is a specific LED assigned to signal activity operation
+	  like file trasnfer, flash write/erase...
+
+	  Defined in Device Tree /options/u-boot node. Refer here for the supported
+	  options [1].
+
+	  [1] dtschema/schemas/options/u-boot.yaml
+
 config LED_BCM6328
 	bool "LED Support for BCM6328"
 	depends on LED && ARCH_BMIPS

drivers/led/led-uclass.c

@@ -163,6 +163,75 @@ int led_boot_blink(void)
 #endif
 #endif
 
+#ifdef CONFIG_LED_ACTIVITY
+static int led_activity_get(struct udevice **devp, int *period_ms)
+{
+	struct led_uc_priv *priv;
+	struct uclass *uc;
+	int ret;
+
+	ret = uclass_get(UCLASS_LED, &uc);
+	if (ret)
+		return ret;
+
+	priv = uclass_get_priv(uc);
+	if (!priv->activity_led_label)
+		return -ENOENT;
+
+	if (period_ms)
+		*period_ms = priv->activity_led_period;
+
+	return led_get_by_label(priv->activity_led_label, devp);
+}
+
+int led_activity_on(void)
+{
+	struct udevice *dev;
+	int ret;
+
+	ret = led_activity_get(&dev, NULL);
+	if (ret)
+		return ret;
+
+	return led_set_state(dev, LEDST_ON);
+}
+
+int led_activity_off(void)
+{
+	struct udevice *dev;
+	int ret;
+
+	ret = led_activity_get(&dev, NULL);
+	if (ret)
+		return ret;
+
+	return led_set_state(dev, LEDST_OFF);
+}
+
+#if defined(CONFIG_LED_BLINK) || defined(CONFIG_LED_SW_BLINK)
+int led_activity_blink(void)
+{
+	struct udevice *dev;
+	int period_ms, ret;
+
+	ret = led_activity_get(&dev, &period_ms);
+	if (ret)
+		return ret;
+
+	ret = led_set_period(dev, period_ms);
+	if (ret) {
+		if (ret != -ENOSYS)
+			return ret;
+
+		/* fallback to ON with no set_period and no SW_BLINK */
+		return led_set_state(dev, LEDST_ON);
+	}
+
+	return led_set_state(dev, LEDST_BLINK);
+}
+#endif
+#endif
+
 static int led_post_bind(struct udevice *dev)
 {
 	struct led_uc_plat *uc_plat = dev_get_uclass_plat(dev);
@@ -227,13 +296,21 @@ static int led_post_probe(struct udevice *dev)
 	return ret;
 }
 
-#ifdef CONFIG_LED_BOOT
+#if defined(CONFIG_LED_BOOT) || defined(CONFIG_LED_ACTIVITY)
 static int led_init(struct uclass *uc)
 {
 	struct led_uc_priv *priv = uclass_get_priv(uc);
 
+#ifdef CONFIG_LED_BOOT
 	priv->boot_led_label = ofnode_options_read_str("boot-led");
 	priv->boot_led_period = ofnode_options_read_int("boot-led-period", 250);
+#endif
+
+#ifdef CONFIG_LED_ACTIVITY
+	priv->activity_led_label = ofnode_options_read_str("activity-led");
+	priv->activity_led_period = ofnode_options_read_int("activity-led-period",
+							    250);
+#endif
 
 	return 0;
 }
@@ -245,7 +322,7 @@ UCLASS_DRIVER(led) = {
 	.per_device_plat_auto	= sizeof(struct led_uc_plat),
 	.post_bind	= led_post_bind,
 	.post_probe	= led_post_probe,
-#ifdef CONFIG_LED_BOOT
+#if defined(CONFIG_LED_BOOT) || defined(CONFIG_LED_ACTIVITY)
 	.init		= led_init,
 	.priv_auto	= sizeof(struct led_uc_priv),
 #endif

include/led.h

@@ -54,14 +54,21 @@ struct led_uc_plat {
  * struct led_uc_priv - Private data the uclass stores about each device
  *
  * @boot_led_label:	Boot LED label
+ * @activity_led_label:	Activity LED label
  * @boot_led_dev:	Boot LED dev
+ * @activity_led_dev:	Activity LED dev
  * @boot_led_period:	Boot LED blink period
+ * @activity_led_period: Activity LED blink period
  */
 struct led_uc_priv {
 #ifdef CONFIG_LED_BOOT
 	const char *boot_led_label;
 	int boot_led_period;
 #endif
+#ifdef CONFIG_LED_ACTIVITY
+	const char *activity_led_label;
+	int activity_led_period;
+#endif
 };
 
 struct led_ops {
@@ -192,4 +199,48 @@ static inline int led_boot_blink(void)
 }
 #endif
 
+#ifdef CONFIG_LED_ACTIVITY
+
+/**
+ * led_activity_on() - turn ON the designated LED for activity
+ *
+ * Return: 0 if OK, -ve on error
+ */
+int led_activity_on(void);
+
+/**
+ * led_activity_off() - turn OFF the designated LED for activity
+ *
+ * Return: 0 if OK, -ve on error
+ */
+int led_activity_off(void);
+
+#if defined(CONFIG_LED_BLINK) || defined(CONFIG_LED_SW_BLINK)
+/**
+ * led_activity_blink() - turn ON the designated LED for activity
+ *
+ * Return: 0 if OK, -ve on error
+ */
+int led_activity_blink(void);
+#else
+/* If LED BLINK is not supported/enabled, fallback to LED ON */
+#define led_activity_blink led_activity_on
+#endif
+#else
+static inline int led_activity_on(void)
+{
+	return -ENOSYS;
+}
+
+static inline int led_activity_off(void)
+{
+	return -ENOSYS;
+}
+
+static inline int led_activity_blink(void)
+{
+	return -ENOSYS;
+}
+#endif
+
 #endif