chore(driver): setup files and module

src/02-driver/.clangd

@@ -0,0 +1,13 @@
+CompileFlags:
+    Add:
+        # Architecture and cross-compilation
+        - "--target=aarch64-linux-gnu"
+
+        # Setup sysroot for buildroot
+        - "--sysroot=/buildroot/output/host/aarch64-buildroot-linux-gnu/sysroot"
+
+        # Add specific header of linux from buildroot
+        - "-I/buildroot/output/build/linux-headers-5.15.148/include"
+        - "-I/buildroot/output/build/linux-headers-5.15.148/arch/arm64/include"
+        - "-I/buildroot/output/build/linux-headers-5.15.148/arch/arm64/include/generated"
+        - "-I/buildroot/output/build/linux-headers-5.15.148/**"

src/02-driver/Makefile

@@ -0,0 +1,44 @@
+EXE=app
+SRCS=$(wildcard *.c)
+
+ifeq ($(target),)
+target=nano
+endif
+
+CFLAGS=-Wall -Wextra -g -c -O0 -MD -std=gnu11
+
+TOOLCHAIN_PATH=/buildroot/output/host/usr/bin/
+TOOLCHAIN=$(TOOLCHAIN_PATH)aarch64-linux-
+CFLAGS+=-mcpu=cortex-a53 -funwind-tables
+##CFLAGS+=-O2 -fno-omit-frame-pointer
+OBJDIR=.obj/nano
+EXEC=$(EXE)
+
+CC=$(TOOLCHAIN)gcc
+LD=$(TOOLCHAIN)gcc
+AR=$(TOOLCHAIN)ar
+STRIP=$(TOOLCHAIN)strip
+
+OBJDIR=.obj/$(target)
+OBJS= $(addprefix $(OBJDIR)/, $(SRCS:.c=.o))
+
+$(OBJDIR)/%o: %c
+	$(CC) $(CFLAGS) $< -o $@
+
+all: $(OBJDIR)/ $(EXEC)
+
+$(EXEC): $(OBJS) $(LINKER_SCRIPT)
+	$(LD) $(OBJS) $(LDFLAGS) -o $@
+
+$(OBJDIR)/:
+	mkdir -p $(OBJDIR)
+
+clean:
+	rm -Rf $(OBJDIR) $(EXEC) $(EXEC)_s *~
+
+clean_all: clean
+	rm -Rf .obj $(EXE) $(EXE)_s $(EXE)_a $(EXE)_a_s $(EXE)_h $(EXE)_h_s
+
+-include $(OBJS:.o=.d)
+
+.PHONY: all clean clean_all

src/02-driver/dts/.clangd

@@ -0,0 +1,33 @@
+CompileFlags:
+    Add:
+        # Architecture and cross-compilation
+        - "--target=aarch64-linux-gnu"
+
+        # Exclude standard library
+        - "-nostdinc"
+
+        # Mandatory kernel definitions
+        - "-D__KERNEL__"
+        - "-DMODULE"
+        - "-DCONFIG_CC_HAS_K_CONSTRAINT=1"
+
+        # Force-included files
+        - "-include"
+        - "/buildroot/output/build/linux-5.15.148/include/linux/compiler-version.h"
+        - "-include"
+        - "/buildroot/output/build/linux-5.15.148/include/linux/kconfig.h"
+        - "-include"
+        - "/buildroot/output/build/linux-5.15.148/include/linux/compiler_types.h"
+
+        # Kernel include paths
+        - "-I/buildroot/output/build/linux-5.15.148/arch/arm64/include"
+        - "-I/buildroot/output/build/linux-5.15.148/arch/arm64/include/generated"
+        - "-I/buildroot/output/build/linux-5.15.148/include"
+        - "-I/buildroot/output/build/linux-5.15.148/arch/arm64/include/uapi"
+        - "-I/buildroot/output/build/linux-5.15.148/arch/arm64/include/generated/uapi"
+        - "-I/buildroot/output/build/linux-5.15.148/include/uapi"
+        - "-I/buildroot/output/build/linux-5.15.148/include/generated/uapi"
+
+        # GCC compiler system include path
+        - "-isystem"
+        - "/buildroot/output/host/lib/gcc/aarch64-buildroot-linux-gnu/11.3.0/include"

src/02-driver/dts/Makefile

@@ -0,0 +1,37 @@
+# Part executed when called from kernel build system:
+ifneq ($(KERNELRELEASE),)
+obj-m += mymodule.o		## name of the generated module
+
+ccflags-y += -Wno-declaration-after-statement -std=gnu11
+mymodule-objs := skeleton.o	## list of objects needed for that module
+
+# Part executed when called from standard make in module source directory:
+else
+include ../../kernel_settings
+PWD := $(shell pwd)
+
+INCL+=-I. -I$(KDIR)/include -I$(KDIR)/arch/arm64/boot/dts
+DTB = mydt.dtb
+DTS = $(DTB:.dtb=.dts)
+
+all: dtb boot
+	$(MAKE) -C $(KDIR) M=$(PWD) ARCH=$(CPU) CROSS_COMPILE=$(TOOLS) modules
+
+dtb: $(DTB)
+$(DTB) : $(DTS)
+	ln -s $(KDIR)/arch/arm/boot/dts arm
+	-cpp $(INCL) -E -P -x assembler-with-cpp $(DTS) | dtc -I dts -O dtb -o $(DTB) -
+	rm arm
+
+boot:
+	mkimage -T script -A arm -C none -d boot.cmd boot.ovl
+
+clean:
+	$(MAKE) -C $(KDIR) M=$(PWD) clean
+	rm -f *.dtb *.ovl
+
+install:
+	$(MAKE) -C $(KDIR) M=$(PWD) INSTALL_MOD_PATH=$(MODPATH) modules_install
+
+endif
+

src/02-driver/dts/boot.cmd

@@ -0,0 +1,10 @@
+setenv bootargs console=ttyS0,115200 earlyprintk root=/dev/mmcblk0p2 rootwait
+
+fatload mmc 0 $kernel_addr_r Image
+#fatload mmc 0 $fdt_addr_r nanopi-neo-plus2.dtb
+fatload mmc 0 $fdt_addr_r mydt.dtb
+
+fdt addr $fdt_addr_r
+fdt resize
+
+booti $kernel_addr_r - $fdt_addr_r

src/02-driver/dts/mydt.dts

@@ -0,0 +1,12 @@
+/dts-v1/;
+
+#include "allwinner/sun50i-h5-nanopi-neo-plus2.dts"
+
+/ {
+        /delete-node/ leds;
+
+        mydevice {
+                compatible = "mydevice";
+                attribute = "text";
+        };
+};

src/02-driver/dts/skeleton.c

@@ -0,0 +1,135 @@
+/* skeleton.c */
+#include <linux/init.h>   /* needed for macros */
+#include <linux/kernel.h> /* needed for debugging */
+#include <linux/module.h> /* needed by all modules */
+
+#include <linux/cdev.h>    /* needed for char device driver */
+#include <linux/fs.h>      /* needed for device drivers */
+#include <linux/uaccess.h> /* needed to copy data to/from user */
+
+#include <linux/device.h> /* needed for sysfs handling */
+#include <linux/miscdevice.h>
+#include <linux/of.h>
+#include <linux/platform_device.h> /* needed for sysfs handling */
+
+static int skeleton_open(struct inode* i, struct file* f)
+{
+    pr_info("skeleton : open operation... major:%d, minor:%d\n",
+            imajor(i),
+            iminor(i));
+    return 0;
+}
+
+static int skeleton_release(struct inode* i, struct file* f)
+{
+    pr_info("skeleton: release operation...\n");
+    return 0;
+}
+
+static ssize_t skeleton_read(struct file* f,
+                             char __user* buf,
+                             size_t count,
+                             loff_t* off)
+{
+    pr_info("skeleton: read operation... read=%ld\n", count);
+    return 0;
+}
+
+static ssize_t skeleton_write(struct file* f,
+                              const char __user* buf,
+                              size_t count,
+                              loff_t* off)
+{
+    pr_info("skeleton: write operation... written=%ld\n", count);
+    return count;
+}
+
+static struct file_operations fops = {
+    .owner   = THIS_MODULE,
+    .open    = skeleton_open,
+    .read    = skeleton_read,
+    .write   = skeleton_write,
+    .release = skeleton_release,
+};
+
+struct miscdevice misc_device = {
+    .minor = MISC_DYNAMIC_MINOR,
+    .fops  = &fops,
+    .name  = "mydevice",
+    .mode  = 0777,
+};
+
+int skeleton_probe(struct platform_device* pdev)
+{
+    pr_info("skeleton - driver probe %llx (%s)- M.m=%d.%d\n",
+            (unsigned long long)pdev,
+            pdev->name,
+            MAJOR(pdev->dev.devt),
+            MINOR(pdev->dev.devt));
+
+    // register misc device ...
+    int ret = misc_register(&misc_device);
+
+    // read device tree attribute
+    struct device_node* dt_node = pdev->dev.of_node;
+    const char* prop            = 0;
+    if (dt_node)
+        ret = of_property_read_string(dt_node, "attribute", &prop);
+    else
+        pr_info("mymodule not found!\n");
+    if ((prop != 0) && (ret == 0))
+        pr_info("attribute=%s (ret=%d)\n", prop, ret);
+
+    return 0;
+}
+int skeleton_remove(struct platform_device* pdev)
+{
+    pr_info("skeleton - sysfs driver remove %llx\n", (unsigned long long)pdev);
+    misc_deregister(&misc_device);
+    return 0;
+}
+void skeleton_shutdown(struct platform_device* pdev)
+{
+    pr_info("skeleton - sysfs driver shutdown %s\n", pdev->name);
+}
+
+struct of_device_id of_skeleton[] = {
+    {
+        .compatible = "mydevice",
+    },
+    {},
+};
+MODULE_DEVICE_TABLE(of, of_skeleton);
+
+static struct platform_driver sysfs_driver = {
+    .probe    = skeleton_probe,
+    .remove   = skeleton_remove,
+    .shutdown = skeleton_shutdown,
+    .driver =
+        {
+            .name           = "mydriver",
+            .of_match_table = of_match_ptr(of_skeleton),
+        },
+};
+
+static int __init skeleton_init(void)
+{
+    pr_info("Linux module skeleton loading...\n");
+    int status = platform_driver_register(&sysfs_driver);
+    pr_info("Linux module skeleton loaded\n");
+    return status;
+}
+
+static void __exit skeleton_exit(void)
+{
+    pr_info("Linux module skeleton exiting...\n");
+    platform_driver_unregister(&sysfs_driver);
+    pr_info("Linux module skeleton unloaded\n");
+}
+
+module_init(skeleton_init);
+module_exit(skeleton_exit);
+
+MODULE_AUTHOR("Daniel Gachet <daniel.gachet@hefr.ch>");
+MODULE_DESCRIPTION("Module skeleton");
+MODULE_LICENSE("GPL");

src/02-driver/main.c

@@ -0,0 +1,18 @@
+#include <fcntl.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/errno.h>
+#include <sys/mman.h>
+#include <unistd.h>
+
+
+int main() {
+
+    int fd = open()
+
+
+
+    return 0;
+}