1 files changed, 110 insertions, 0 deletions
diff --git a/driver/main.c b/driver/main.c
new file mode 100644
index 0000000..d8ea7fc
--- /dev/null
+++ b/driver/main.c
@@ -0,0 +1,110 @@
+#include <linux/cdev.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/io.h>
+
+#include "fopdrv.h"
+#include "config.h"
+
+int one = 0;
+module_param(one, int, 0400);
+MODULE_PARM_DESC(one, "first parameter, only printed on init");
+
+int not_named_two = 0;
+module_param_named(two, not_named_two, int, 0400);
+MODULE_PARM_DESC(not_named_two, "second parameter, only printed on init");
+
+struct cdev *cdev;
+struct device *dev;
+struct class *class;
+dev_t node;
+struct file_operations fops = {
+	.read = fop_read,
+	.write = fop_write,
+	.open = fop_open,
+	.release = fop_release,
+};
+
+static int mod_init(void) {
+	int err;
+
+	err = alloc_chrdev_region(&node, 0, 1, DRV_NAME);
+	if (err < 0) {
+		printk(KERN_ERR "alloc_chrdev_region error %d\n", err);
+		goto return_err;
+	}
+
+	class = class_create(DRV_NAME);
+	if (IS_ERR_OR_NULL(class)) {
+		err = PTR_ERR(class);
+		printk(KERN_ERR "class_create error %d\n", err);
+		goto free_class;
+	}
+
+	cdev = cdev_alloc();
+	if (!cdev) {
+		err = ENOMEM;
+		goto free_cdev;
+	}
+
+	cdev->ops = &fops;
+	cdev_init(cdev, &fops);
+	err = cdev_add(cdev, node, 1);
+	if (err < 0) {
+		printk(KERN_ERR "cdev_add error %d\n", err);
+		goto free_cdev;
+	}
+
+	dev = device_create(class, NULL, node, NULL, DRV_NAME);
+	if (IS_ERR_OR_NULL(dev)) {
+		err = PTR_ERR(dev);
+		printk(KERN_ERR "device_create error %d\n", err);
+		goto free_device;
+	}
+
+	printk("%s() -> 0 (%d:%d)\n", __PRETTY_FUNCTION__, MAJOR(node), MINOR(node));
+	printk("one = %d, two = %d\n", one, not_named_two);
+
+	// configure gpio mux
+	uint32_t* conf_gpmc_a3 = ioremap(TI_AM335X_CM_GPMC_A3_ADDR, sizeof(ti_am335x_word_t));
+	if (conf_gpmc_a3 == NULL)
+		return -EINVAL;
+	barrier();
+	uint32_t val = ioread32(conf_gpmc_a3); rmb();
+	val &= ~0x7;
+	val |= 0x7;
+	iowrite32(val, conf_gpmc_a3); wmb();
+	iounmap(conf_gpmc_a3);
+
+	// configure output pin
+	ti_am335x_word_t* gpio1 = ioremap(TI_AM335X_GPIO1_ADDR, GPIO_REG_SIZE);
+	barrier();
+	ti_am335x_word_t oe_reg = ioread32(gpio1 + GPIO_OE); rmb();
+	oe_reg &= ~(1<<PIN); // 0=output
+	iowrite32(oe_reg, gpio1 + GPIO_OE); wmb();
+	iounmap(gpio1);
+
+	return 0;
+
+free_device:
+	device_destroy(class, node);
+free_cdev:
+	cdev_del(cdev);
+free_class:
+	class_destroy(class);
+return_err:
+	printk("%s() -> %d\n", __PRETTY_FUNCTION__, err);
+	return err;
+}
+
+static void mod_exit(void) {
+	device_destroy(class, node);
+	cdev_del(cdev);
+	class_destroy(class);
+	printk("%s()\n", __PRETTY_FUNCTION__);
+}
+
+module_init(mod_init);
+module_exit(mod_exit);
+MODULE_LICENSE("Dual MIT/GPL");
+