still works 2

driver/counter.c

@@ -5,6 +5,7 @@
 #include <linux/platform_device.h>
 #include <linux/of_device.h>
 #include <linux/gpio/consumer.h>
+#include <linux/spi/spi.h>
 
 /* Meta Information */
 MODULE_LICENSE("GPL");
@@ -12,22 +13,22 @@ MODULE_AUTHOR("Wolfgang Hottgenroth");
 MODULE_DESCRIPTION("A simple LKM to parse the device tree for a specific device and its properties");
 
 /* Declate the probe and remove functions */
-static int dt_probe(struct platform_device *pdev);
-static void dt_remove(struct platform_device *pdev);
+static int dt_leds_probe(struct platform_device *pdev);
+static void dt_leds_remove(struct platform_device *pdev);
 
-static struct of_device_id my_driver_ids[] = {
+static struct of_device_id leds_driver_ids[] = {
   {
-    .compatible = "hottis,counter",
+    .compatible = "hottis,leds",
   }, { /* sentinel */ }
 };
-MODULE_DEVICE_TABLE(of, my_driver_ids);
+MODULE_DEVICE_TABLE(of, leds_driver_ids);
 
-static struct platform_driver my_driver = {
-  .probe = dt_probe,
-  .remove = dt_remove,
+static struct platform_driver leds_driver = {
+  .probe = dt_leds_probe,
+  .remove = dt_leds_remove,
   .driver = {
-    .name = "my_device_driver",
-    .of_match_table = my_driver_ids,
+    .name = "leds_device_driver",
+    .of_match_table = leds_driver_ids,
   },
 };
 
@@ -36,13 +37,40 @@ static struct gpio_desc *red_led = NULL;
 static struct gpio_desc *blue_led = NULL;
 
 
+/* spi stuff */
+static int dt_ls7366r_probe(struct spi_device *client);
+static void dt_ls7366r_remove(struct spi_device *client);
+
+static struct of_device_id ls7366r_driver_ids[] = {
+  {
+    .compatible = "hottis,ls7366r",
+  }, {}
+};
+MODULE_DEVICE_TABLE(of, ls7366r_driver_ids);
+
+static struct spi_device_id ls7366r[] = {
+  { "ls7366r", 0 },
+  {},
+};
+MODULE_DEVICE_TABLE(spi, ls7366r);
+
+static struct spi_driver ls7366r_driver = {
+  .probe = dt_ls7366r_probe,
+  .remove = dt_ls7366r_remove,
+  .id_table = ls7366r,
+  .driver = {
+    .name = "ls7366r_device_driver",
+    .of_match_table = ls7366r_driver_ids,
+  },
+};
+
 /**
  * @brief This function is called on loading the driver 
  */
-static int dt_probe(struct platform_device *pdev) {
+static int dt_leds_probe(struct platform_device *pdev) {
   struct device *dev = &pdev->dev;
 
-  printk("counter - probing\n");
+  printk("counter - leds probing\n");
 
   if(!device_property_present(dev, "red-led-gpio")) {
     printk("counter - Error! Device property 'red-led-gpio' not found!\n");
@@ -72,22 +100,46 @@ static int dt_probe(struct platform_device *pdev) {
 /**
  * @brief This function is called on unloading the driver 
  */
-static void dt_remove(struct platform_device *pdev) {
-  printk("counter - removing\n");
+static void dt_leds_remove(struct platform_device *pdev) {
+  printk("counter - leds removing\n");
   gpiod_put(red_led);
   gpiod_put(blue_led);
 }
 
+static int dt_ls7366r_probe(struct spi_device *client) {
+  printk("counter - ls7366r probing\n");
+  
+  int ret = spi_setup(client);
+  if (ret < 0) {
+    printk("counter - Error! Failed to set up the SPI bus\n");
+    return ret;
+  }
+
+  return 0;
+}
+
+
+static void dt_ls7366r_remove(struct spi_device *client) {
+  printk("counter - ls7366r removing\n");
+}
+
+
 /**
  * @brief This function is called, when the module is loaded into the kernel
  */
 static int __init my_init(void) {
-  printk("counter - Loading the driver...\n");
-  if(platform_driver_register(&my_driver)) {
+  printk("counter - Loading the leds driver...\n");
+  if(platform_driver_register(&leds_driver)) {
     printk("dt_gpio - Error! Could not load driver\n");
     return -1;
   }
 
+  printk("counter - Loading the ls7366r driver...\n");
+  if (spi_register_driver(&ls7366r_driver)) {
+    printk("counter - Error! Could not load spi driver\n");
+    return -1;
+  }
+
   printk("counter - red led on\n");
   gpiod_set_value(red_led, 1);
 
@@ -98,12 +150,14 @@ static int __init my_init(void) {
  * @brief This function is called, when the module is removed from the kernel
  */
 static void __exit my_exit(void) {
-  printk("counter - Unload driver");
-
   printk("counter - red led off\n");
   gpiod_set_value(red_led, 0);
 
-  platform_driver_unregister(&my_driver);
+  printk("counter - Unloading the leds driver...\n");
+  platform_driver_unregister(&leds_driver);
+
+  printk("counter - Unloading the ls7366r driver...\n");
+  spi_unregister_driver(&ls7366r_driver);
 }
 
 module_init(my_init);

driver/counter.dts

@@ -3,14 +3,40 @@
 / {
   compatible = "brcm,bcm2835";
   fragment@0 {
-    target-path = "/";
+    target-path = "/soc";
     __overlay__ {
       status = "okay";
-      counter {
-        compatible = "hottis,counter";
+
+      leds {
+        compatible = "hottis,leds";
         red-led-gpio = <&gpio 26 0>; 
         blue-led-gpio = <&gpio 21 0>; 
       };
     };
   };
+
+  fragment@1 {
+    target = <&spidev0>;
+    __overlay__ {
+      status = "disabled";
+    };
+  };
+
+  fragment@2 {
+    target = <&spi0>;
+    __overlay__ {
+      status = "okay";
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      ls7366r: ls7366r0@0 {
+        compatible = "hottis,ls7366r";
+        reg = <0x0>;
+        spi-max-frequency = <1000000>;
+        spi-bits-per-word = <8>;
+        status = "okay";
+      };
+    };
+  };
+
 };