dm: led: Add support for getting the state of an LED

It is useful to be able to read the LED as well as write it. Add this to
the uclass and update the GPIO driver.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Ziping Chen <techping.chan@gmail.com>

diff --git a/drivers/led/led-uclass.c b/drivers/led/led-uclass.c
index b30346913b9fa5bf6b2f179c43f526263a6fcc7e..ea5fbabadf3b78aaa31f202c86d907cdf8622da5 100644 (file)
--- a/drivers/led/led-uclass.c
+++ b/drivers/led/led-uclass.c
@@ -42,6 +42,16 @@ int led_set_state(struct udevice *dev, enum led_state_t state)
        return ops->set_state(dev, state);
 }
 
+enum led_state_t led_get_state(struct udevice *dev)
+{
+       struct led_ops *ops = led_get_ops(dev);
+
+       if (!ops->get_state)
+               return -ENOSYS;
+
+       return ops->get_state(dev);
+}
+
 UCLASS_DRIVER(led) = {
        .id             = UCLASS_LED,
        .name           = "led",

diff --git a/drivers/led/led_gpio.c b/drivers/led/led_gpio.c
index af8133d3c700b26c752def58b02543ac62002202..789d15600fdc1092e66c8279e54b8d6288ee4543 100644 (file)
--- a/drivers/led/led_gpio.c
+++ b/drivers/led/led_gpio.c
@@ -24,10 +24,31 @@ static int gpio_led_set_state(struct udevice *dev, enum led_state_t state)
 
        if (!dm_gpio_is_valid(&priv->gpio))
                return -EREMOTEIO;
+       switch (state) {
+       case LEDST_OFF:
+       case LEDST_ON:
+               break;
+       default:
+               return -ENOSYS;
+       }
 
        return dm_gpio_set_value(&priv->gpio, state);
 }
 
+static enum led_state_t gpio_led_get_state(struct udevice *dev)
+{
+       struct led_gpio_priv *priv = dev_get_priv(dev);
+       int ret;
+
+       if (!dm_gpio_is_valid(&priv->gpio))
+               return -EREMOTEIO;
+       ret = dm_gpio_get_value(&priv->gpio);
+       if (ret < 0)
+               return ret;
+
+       return ret ? LEDST_ON : LEDST_OFF;
+}
+
 static int led_gpio_probe(struct udevice *dev)
 {
        struct led_uc_plat *uc_plat = dev_get_uclass_platdata(dev);
@@ -88,6 +109,7 @@ static int led_gpio_bind(struct udevice *parent)
 
 static const struct led_ops gpio_led_ops = {
        .set_state      = gpio_led_set_state,
+       .get_state      = gpio_led_get_state,
 };
 
 static const struct udevice_id led_gpio_ids[] = {

diff --git a/include/led.h b/include/led.h
index 8af87ea8ea8c68a45b420dec1d18643724dd3087..bbab4d14c9856025cd06a0fa1dcd9ca6357064d6 100644 (file)
--- a/include/led.h
+++ b/include/led.h
@@ -33,6 +33,14 @@ struct led_ops {
         * @return 0 if OK, -ve on error
         */
        int (*set_state)(struct udevice *dev, enum led_state_t state);
+
+       /**
+        * led_get_state() - get the state of an LED
+        *
+        * @dev:        LED device to change
+        * @return LED state led_state_t, or -ve on error
+        */
+       enum led_state_t (*get_state)(struct udevice *dev);
 };
 
 #define led_get_ops(dev)       ((struct led_ops *)(dev)->driver->ops)
@@ -55,4 +63,12 @@ int led_get_by_label(const char *label, struct udevice **devp);
  */
 int led_set_state(struct udevice *dev, enum led_state_t state);
 
+/**
+ * led_get_state() - get the state of an LED
+ *
+ * @dev:       LED device to change
+ * @return LED state led_state_t, or -ve on error
+ */
+enum led_state_t led_get_state(struct udevice *dev);
+
 #endif

diff --git a/test/dm/led.c b/test/dm/led.c
index ebb9b46584865cacc9e72cbf1b5843ef7958753a..68aa39bd4d0809ae08761f2dd4a0b80d4306545c 100644 (file)
--- a/test/dm/led.c
+++ b/test/dm/led.c
@@ -43,9 +43,11 @@ static int dm_test_led_gpio(struct unit_test_state *uts)
        ut_asserteq(0, sandbox_gpio_get_value(gpio, offset));
        ut_assertok(led_set_state(dev, LEDST_ON));
        ut_asserteq(1, sandbox_gpio_get_value(gpio, offset));
+       ut_asserteq(LEDST_ON, led_get_state(dev));
 
        ut_assertok(led_set_state(dev, LEDST_OFF));
        ut_asserteq(0, sandbox_gpio_get_value(gpio, offset));
+       ut_asserteq(LEDST_OFF, led_get_state(dev));
 
        return 0;
 }