save

driver/counter.c

@@ -1,21 +1,59 @@
-#include <linux/module.h>
-#include <linux/kernel.h>
 #include <linux/init.h>
+#include <linux/module.h>
+#include <linux/gpio/consumer.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Du");
+MODULE_DESCRIPTION("GPIO consumer API example for two LEDs");
+
+static struct gpio_desc *led_blue;
+static struct gpio_desc *led_red;
+
+static int __init led_consumer_init(void)
+{
+    struct device *dev = NULL;
+
+    pr_info("GPIO consumer LED module loading\n");
+
+    // GPIOs per Name aus dem Device Tree holen (via label oder node property)
+    led_blue = gpiod_get(dev, "led-blue", GPIOD_OUT_LOW);
+    if (IS_ERR(led_blue)) {
+        pr_err("Failed to get GPIO for blue LED\n");
+        return PTR_ERR(led_blue);
+    }
+
+    led_red = gpiod_get(dev, "led-red", GPIOD_OUT_LOW);
+    if (IS_ERR(led_red)) {
+        pr_err("Failed to get GPIO for red LED\n");
+        gpiod_put(led_blue);
+        return PTR_ERR(led_red);
+    }
+
+    // Test: LEDs einschalten
+    gpiod_set_value(led_blue, 1);
+    gpiod_set_value(led_red, 1);
+    msleep(500);
+    gpiod_set_value(led_blue, 0);
+    gpiod_set_value(led_red, 0);
+
+    pr_info("LEDs blinked using gpio/consumer\n");
 
-static int __init counter_init(void) {
-    pr_info("counter: LKM loaded.\n");
     return 0;
 }
 
-static void __exit counter_exit(void) {
+static void __exit led_consumer_exit(void)
-    pr_info("counter: LKM unloaded.\n");
+{
+    gpiod_set_value(led_blue, 0);
+    gpiod_set_value(led_red, 0);
+
+    gpiod_put(led_blue);
+    gpiod_put(led_red);
+
+    pr_info("GPIO consumer LED module unloaded\n");
 }
 
-module_init(counter_init);
+module_init(led_consumer_init);
-module_exit(counter_exit);
+module_exit(led_consumer_exit);
-
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Wolfgang Hottgenroth <wolfgang.hottgenroth@icloud.com>");
-MODULE_DESCRIPTION("LKM for MainsCnt counter module");
-MODULE_VERSION("0.1");
 

dtoverlay/counter.dts

@@ -19,6 +19,28 @@
             };
         };
     };
+
+    fragment@1 {
+        target-path = "/";
+        __overlay__ {
+            mygpioleds {
+                compatible = "my,gpio-led-controller";
+                pinctrl-names = "default";
+                pinctrl-0 = <&gpio_led_blue &gpio_led_red>;
+
+                led-blue {
+                    gpios = <&gpio 26 0>;
+                    label = "led-blue";
+                };
+
+                led-red {
+                    gpios = <&gpio 21 0>;
+                    label = "led-red";
+                };
+            };
+        };
+    };
+
 };