Task08: irq hadling

08_irq_handling/src/Makefile

@@ -0,0 +1,44 @@
+TARGET = led_module
+
+ifneq ($(KERNELRELEASE),)
+
+obj-m := $(TARGET).o
+$(TARGET)-objs := led_mod.o
+
+else
+
+
+ifneq ($(QUEMU),)
+BUILD_KERNEL=~/projects/LinuxKernelCoursePro/kernel/buildroot-2021.02.7/output/build/linux-5.10.10/
+$(info  1 $(QUEMU))
+else
+BUILD_KERNEL=/lib/modules/$(shell uname -r)/build
+$(info  2 $(QUEMU))
+endif
+
+
+KERNELDIR := $(BUILD_KERNEL)
+
+.PHONY: all clean
+
+all:
+	$(MAKE) -C $(KERNELDIR) M=$(CURDIR) modules
+clean:
+	$(MAKE) -C $(KERNELDIR) M=$(CURDIR) clean
+install: 
+	sudo insmod ./$(TARGET).ko
+	#- lsmod | grep head -n
+remove:
+	sudo rmmod $(TARGET)
+	#- lsmod | grep head -n
+test:
+	#sudo dmesg -C
+	sudo insmod $(TARGET).ko
+	sudo rmmod $(TARGET)
+
+check:
+	- $(BUILD_KERNEL)/scripts/checkpatch.pl -f --no-tree --fix ./main.c
+
+endif
+
+

08_irq_handling/src/led_mod.c

@@ -0,0 +1,156 @@
+#define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__
+
+#include <linux/module.h>
+#include <linux/gpio.h>
+#include <linux/ktime.h>
+#include <linux/interrupt.h>
+
+#define GPIO_NUMBER(port, bit) (32 * (port) + (bit))
+
+/*	https://linux-sunxi.org/Xunlong_Orange_Pi_PC#LEDs
+ *  Board config for OPI-PC:
+ *	LED GREEN (PL10): GPIO_11_10
+ *	LED RED   (PA15): GPIO_0_15  
+ *	BUTTON    (PG7) : GPIO_6_7
+ *
+ *  https://linux-sunxi.org/Xunlong_Orange_Pi_Zero#LEDs
+ *  Board config for OPI-Zero:
+ *	LED GREEN (PL10): GPIO_11_10 
+ *	LED RED   (PA17): GPIO_0_17 
+ *	BUTTON    (PG7) : GPIO_6_7
+ *  
+ */
+
+#define LED_GREEN GPIO_NUMBER(11, 10)
+#define LED_RED GPIO_NUMBER(0, 17)
+//#define BUTTON GPIO_NUMBER(6, 7)
+#define BUTTON GPIO_NUMBER(0, 1) //Activate PA1
+
+//#define TIMER_ENABLE 1
+#define IRQ_ENABLE 1
+
+static int ledg_gpio = -1;
+static int ledr_gpio = -1;
+static int button_gpio = -1;
+static int button_state = -1;
+static int button_cnt = -1;
+
+#ifdef TIMER_ENABLE
+static ktime_t timer_period;
+struct hrtimer button_timer;
+
+static enum hrtimer_restart timer_callback(struct hrtimer *timer)
+{
+	int cur_button_state;
+
+	cur_button_state = gpio_get_value(button_gpio);
+	button_cnt = (cur_button_state == button_state) ? (button_cnt + 1) : 0;
+	button_state = cur_button_state;
+	gpio_set_value(ledr_gpio, ((button_cnt == 20) ? 1 : 0));
+	if (button_cnt >= 20)
+		gpio_set_value(ledg_gpio, !button_state);
+	hrtimer_forward(timer, timer->base->get_time(), timer_period);
+	return HRTIMER_RESTART;  //restart timer
+}
+#endif
+
+static int led_gpio_init(int gpio, int *led_gpio)
+{
+	int res;
+
+	res = gpio_direction_output(gpio, 0);
+	if (res != 0)
+		return res;
+
+	*led_gpio = gpio;
+	return 0;
+}
+
+static int button_gpio_init(int gpio)
+{
+	int res;
+
+	res = gpio_request(gpio, "Onboard user button");
+	if (res != 0)
+		return res;
+
+	res = gpio_direction_input(gpio);
+	if (res != 0)
+		goto err_input;
+
+	button_gpio = gpio;
+	pr_info("Init GPIO%d OK\n", button_gpio);
+	button_state = gpio_get_value(button_gpio);
+	button_cnt = 0;
+
+	return 0;
+
+err_input:
+	gpio_free(gpio);
+	return res;
+}
+
+static void button_gpio_deinit(void)
+{
+	if (button_gpio >= 0) {
+		gpio_free(button_gpio);
+		pr_info("Deinit GPIO%d\n", button_gpio);
+	}
+}
+
+/* Module entry/exit points */
+static int __init gpio_poll_init(void)
+{
+	int res;
+	pr_info("GPIO Init\n");
+
+	res = button_gpio_init(BUTTON);
+	if (res != 0) {
+		pr_err("Can't set GPIO%d for button\n", BUTTON);
+		return res;
+	}
+#ifdef TIMER_ENABLE
+	timer_period = ktime_set(0, 1000000);      /*1 msec*/
+	hrtimer_init(&button_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	hrtimer_start(&button_timer, timer_period, HRTIMER_MODE_REL);
+	button_timer.function = timer_callback;
+#endif
+	res = led_gpio_init(LED_GREEN, &ledg_gpio);
+	if (res != 0) {
+		pr_err("Can't set GPIO%d for output\n", LED_GREEN);
+		goto err_led;
+	}
+
+	gpio_set_value(ledg_gpio, 0);
+
+	res = led_gpio_init(LED_RED, &ledr_gpio);
+	if (res != 0) {
+		pr_err("Can't set GPIO%d for output\n", LED_RED);
+		goto err_led;
+	}
+	gpio_set_value(ledr_gpio, 1);
+
+	return 0;
+
+err_led:
+	button_gpio_deinit();
+	return res;
+}
+
+static void __exit gpio_poll_exit(void)
+{
+	gpio_set_value(ledg_gpio, 1);
+	gpio_set_value(ledr_gpio, 0);
+	button_gpio_deinit();
+#ifdef TIMER_ENABLE
+	hrtimer_cancel(&button_timer);
+#endif
+}
+
+module_init(gpio_poll_init);
+module_exit(gpio_poll_exit);
+
+MODULE_AUTHOR("Vitaliy Zhyrko vitaliyzh@gmail.com>");
+MODULE_DESCRIPTION("LED Test");
+MODULE_LICENSE("GPL");
+MODULE_VERSION("0.1");