feat(lab03): add ex5 - sysfs

src/02-driver/sysfs/.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/sysfs/Makefile

@@ -0,0 +1,22 @@
+# Part executed when called from kernel build system:
+ifneq ($(KERNELRELEASE),)
+obj-m += mymodule.o		## name of the generated module
+
+mymodule-objs := skeleton.o	## list of objects needed for that module
+
+# Part executed when called from standard make in module source directory:
+else
+include ../../buildroot_path
+include ../../kernel_settings
+PWD := $(shell pwd)
+
+all:
+	$(MAKE) -C $(KDIR) M=$(PWD) ARCH=$(CPU) CROSS_COMPILE=$(TOOLS) modules
+
+clean:
+	$(MAKE) -C $(KDIR) M=$(PWD) clean
+
+install:
+	$(MAKE) -C $(KDIR) M=$(PWD) INSTALL_MOD_PATH=$(MODPATH) modules_install
+
+endif

src/02-driver/sysfs/skeleton.c

@@ -0,0 +1,60 @@
+#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/platform_device.h> /* needed for sysfs handling */
+
+static int val;
+
+ssize_t sysfs_show_val(struct device* dev, struct device_attribute* attr, char* buf) {
+    pr_info("sysfs_show_val: val=%d\n", val);
+    sprintf(buf, "%d\n", val);
+    return strlen(buf);
+}
+
+ssize_t sysfs_store_val(struct device* dev, struct device_attribute* attr, const char* buf, size_t count) {
+    pr_info("sysfs_store_val: buf=%s\n", buf);
+    val = simple_strtol(buf, 0, 10);
+    return count;
+}
+
+DEVICE_ATTR(val, 0664, sysfs_show_val, sysfs_store_val);
+
+static struct class* sysfs_class;
+static struct device* sysfs_device;
+
+static int __init skeleton_init(void) {
+
+    int status = 0;
+
+    sysfs_class = class_create(THIS_MODULE, "my_sysfs_class");
+    sysfs_device = device_create(sysfs_class, NULL, 0, NULL, "my_sysfs_device");
+    if (status == 0) status = device_create_file(sysfs_device, &dev_attr_val);
+
+    pr_info("Linux module skeleton loaded\n");
+    return 0;
+}
+
+
+static void __exit skeleton_exit(void) {
+
+    device_remove_file(sysfs_device, &dev_attr_val);
+    device_destroy(sysfs_class, 0);
+    class_destroy(sysfs_class);
+
+    pr_info("Linux module skeleton unloaded\n");
+}
+
+module_init (skeleton_init);
+module_exit (skeleton_exit);
+
+MODULE_AUTHOR("Fastium <fastium.pro@proton.me>");
+MODULE_AUTHOR("Klagarge <remi@heredero.ch>");
+MODULE_DESCRIPTION ("Module pilot charachter oriented");
+MODULE_LICENSE ("GPL");