Implemented task08 with the buttons handling via IRQ

08_irq_handling/Makefile

@@ -0,0 +1,11 @@
+KERNELDIR ?=/home/valenti/Development/Embedded/exercise8/build_orange_zero_image/build/linux-5.10.10/
+
+ifneq ($(KERNELRELEASE),)
+	obj-m := led_mod_irq.o
+else
+
+all:
+	$(MAKE) CFLAGS_MODULE="-DDEBUG -DORANGE_PI_ZERO" -C $(KERNELDIR) M=$(PWD) modules
+clean:
+	$(MAKE) -C $(KERNELDIR) M=$(PWD) clean
+endif

08_irq_handling/led_mod_irq.c

@@ -0,0 +1,276 @@
+#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>
+#include <linux/of.h>
+#include <linux/jiffies.h>
+#include <linux/slab.h>
+#include <linux/ktime.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    (PA6) : GPIO_0_6
+ *  
+ */
+
+// https://gist.github.com/rday/c796e3307c4087ae3539
+// https://elixir.bootlin.com/linux/latest/source/drivers/iio/humidity/dht11.c#L310
+// https://www.kernel.org/doc/Documentation/gpio/board.txt
+// https://elixir.bootlin.com/linux/latest/source/drivers/input/touchscreen/ts4800-ts.c#L211
+// https://linux-kernel-labs.github.io/refs/heads/master/labs/deferred_work.html
+// https://elixir.bootlin.com/linux/latest/source/drivers/input/keyboard/matrix_keypad.c#L189
+
+#ifdef ORANGE_PI_PC
+#error "Implement the necessary port mappings"
+#endif
+#ifdef ORANGE_PI_ZERO
+#define LED_GREEN GPIO_NUMBER(11, 10)
+#define LED_RED GPIO_NUMBER(0, 17)
+#define BUTTON GPIO_NUMBER(0, 6)
+#endif
+
+#define GREEN_LED_TOGGLE_TIMEOUT 400
+#define RED_LED_TOGGLE_TIMEOUT 50
+
+struct irq_module_data {
+	int ledg_gpio;
+	int ledr_gpio;
+	int button_gpio;
+	int button_state;
+	int button_cnt;
+	int ledr_gpio_state;
+	struct delayed_work ledg_check_work;
+	struct delayed_work ledr_toggle_work;
+	spinlock_t lock;
+};
+
+struct irq_module_data *module_data = NULL;
+
+static void check_green_delayed_handler(struct work_struct *work)
+{
+	pr_info("Delayed work handler\n");
+
+	struct irq_module_data *user_data = container_of(
+		work, struct irq_module_data, ledg_check_work.work);
+
+	spin_lock(&user_data->lock);
+	int button_gpio_state = gpio_get_value(user_data->button_gpio);
+	int prev_gpio_value = user_data->button_state;
+
+	user_data->button_state = button_gpio_state;
+	spin_unlock(&user_data->lock);
+
+	if (button_gpio_state == prev_gpio_value) {
+		pr_info("Delayed work handler:Disabled green led\n");
+		gpio_set_value(user_data->ledg_gpio, 0);
+	} else {
+		pr_info("Delayed work handler:Enabled green led\n");
+		gpio_set_value(user_data->ledg_gpio, 1);
+	}
+}
+
+static void toggle_red_delayed_handler(struct work_struct *work)
+{
+	struct irq_module_data *user_data = container_of(
+		work, struct irq_module_data, ledr_toggle_work.work);
+	spin_lock(&user_data->lock);
+	gpio_set_value(user_data->ledr_gpio, !user_data->ledr_gpio_state);
+	user_data->ledr_gpio_state = !user_data->ledr_gpio_state;
+	spin_unlock(&user_data->lock);
+}
+
+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;
+
+	module_data->button_gpio = gpio;
+	pr_info("Init GPIO%d OK\n", module_data->button_gpio);
+	module_data->button_state = gpio_get_value(module_data->button_gpio);
+	pr_info("Got button value: %d\n", module_data->button_state);
+	module_data->button_cnt = 0;
+
+	return 0;
+
+err_input:
+	gpio_free(gpio);
+	return res;
+}
+
+static irqreturn_t button_module_irq_handler(int irq, void *user_data)
+{
+	struct irq_module_data *irq_user_data =
+		(struct irq_module_data *)user_data;
+	unsigned long flags;
+	uint8_t button_value;
+
+	spin_lock_irqsave(&irq_user_data->lock, flags);
+
+	button_value = gpio_get_value(irq_user_data->button_gpio);
+	pr_info("Inside interrupt handler, button value:%d, prev_value:%d\n",
+		button_value, irq_user_data->button_state);
+	if (module_data->button_state == button_value)
+		goto out;
+
+	if (button_value == 0) {
+		pr_info("Canceled delayed work because of the button_value==0\n");
+		cancel_delayed_work(&irq_user_data->ledg_check_work);
+		cancel_delayed_work(&irq_user_data->ledr_toggle_work);
+
+		gpio_set_value(irq_user_data->ledr_gpio, 1);
+		irq_user_data->ledr_gpio_state = 1;
+		gpio_set_value(irq_user_data->ledg_gpio, 1);
+
+		schedule_delayed_work(&irq_user_data->ledr_toggle_work,
+				      msecs_to_jiffies(RED_LED_TOGGLE_TIMEOUT));
+
+		module_data->button_state = button_value;
+	} else {
+		pr_info("Scheduled delayed work\n");
+
+		module_data->button_state = button_value;
+
+		gpio_set_value(irq_user_data->ledr_gpio, 1);
+		irq_user_data->ledr_gpio_state = 1;
+		schedule_delayed_work(
+			&irq_user_data->ledg_check_work,
+			msecs_to_jiffies(GREEN_LED_TOGGLE_TIMEOUT));
+		schedule_delayed_work(&irq_user_data->ledr_toggle_work,
+				      msecs_to_jiffies(RED_LED_TOGGLE_TIMEOUT));
+	}
+out:
+	spin_unlock_irqrestore(&irq_user_data->lock, flags);
+	return IRQ_HANDLED;
+}
+
+static void button_gpio_deinit(struct irq_module_data *module_data_arg)
+{
+	if (module_data_arg->button_gpio >= 0) {
+		gpio_free(module_data_arg->button_gpio);
+		pr_info("Deinit GPIO%d\n", module_data_arg->button_gpio);
+	}
+}
+
+static void gpio_setup_irq(void)
+{
+	int irq;
+	int rc;
+
+	irq = gpio_to_irq(BUTTON);
+	rc = request_irq(irq, button_module_irq_handler,
+			 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
+			 "button_module_irq_handler", module_data);
+}
+
+static void gpio_deinit_irq(void)
+{
+	int irq = gpio_to_irq(BUTTON);
+
+	free_irq(irq, module_data);
+}
+
+/* Module entry/exit points */
+static int __init gpio_irq_init(void)
+{
+	module_data = kzalloc(sizeof(struct irq_module_data), GFP_KERNEL);
+
+	if (!module_data)
+		return -ENOMEM;
+
+	module_data->button_cnt = -1;
+	module_data->button_state = -1;
+
+	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);
+		kfree(module_data);
+		return res;
+	}
+
+	res = led_gpio_init(LED_GREEN, &module_data->ledg_gpio);
+	if (res != 0) {
+		pr_err("Can't set GPIO%d for output\n", LED_GREEN);
+		goto err_led;
+	}
+
+	gpio_set_value(module_data->ledg_gpio, 0);
+
+	res = led_gpio_init(LED_RED, &module_data->ledr_gpio);
+	if (res != 0) {
+		pr_err("Can't set GPIO%d for output\n", LED_RED);
+		goto err_led;
+	}
+	gpio_set_value(module_data->ledr_gpio, 1);
+	module_data->ledr_gpio_state = 1;
+
+	INIT_DELAYED_WORK(&module_data->ledg_check_work,
+			  check_green_delayed_handler);
+	INIT_DELAYED_WORK(&module_data->ledr_toggle_work,
+			  toggle_red_delayed_handler);
+	spin_lock_init(&module_data->lock);
+
+	gpio_setup_irq();
+	return 0;
+
+err_led:
+	button_gpio_deinit(module_data);
+	kfree(module_data);
+	return res;
+}
+
+static void __exit gpio_irq_exit(void)
+{
+	gpio_deinit_irq();
+	cancel_delayed_work_sync(&module_data->ledg_check_work);
+	cancel_delayed_work_sync(&module_data->ledr_toggle_work);
+
+	gpio_set_value(module_data->ledg_gpio, 1);
+	gpio_set_value(module_data->ledr_gpio, 0);
+
+	button_gpio_deinit(module_data);
+
+	kfree(module_data);
+}
+
+module_init(gpio_irq_init);
+module_exit(gpio_irq_exit);
+
+MODULE_AUTHOR("Valentyn Korniienko [email protected]>");
+MODULE_DESCRIPTION("LED Test");
+MODULE_LICENSE("GPL");
+MODULE_VERSION("0.1");

08_irq_handling/led_mod.c → 08_irq_handling/led_mod_polling.c

@@ -17,14 +17,18 @@
  *  Board config for OPI-Zero:
  *	LED GREEN (PL10): GPIO_11_10 
  *	LED RED   (PA17): GPIO_0_17 
- *	BUTTON    (PG7) : GPIO_6_7
+ *	BUTTON    (PA6) : GPIO_0_6
  *  
  */
 
+#ifdef ORANGE_PI_PC
+#error "Implement the necessary port mappings"
+#endif
+#ifdef ORANGE_PI_ZERO
 #define LED_GREEN GPIO_NUMBER(11, 10)
-#define LED_RED GPIO_NUMBER(0, 15)
-#define BUTTON GPIO_NUMBER(6, 7)
-
+#define LED_RED GPIO_NUMBER(0, 17)
+#define BUTTON GPIO_NUMBER(0, 6)
+#endif
 //#define TIMER_ENABLE 1
 
 static int ledg_gpio = -1;
@@ -44,11 +48,11 @@ static enum hrtimer_restart timer_callback(struct hrtimer *timer)
 	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(ledr_gpio, ((button_cnt == 400) ? 1 : 0));
+	if (button_cnt >= 400)
 		gpio_set_value(ledg_gpio, !button_state);
 	hrtimer_forward(timer, timer->base->get_time(), timer_period);
-	return HRTIMER_RESTART;  //restart timer
+	return HRTIMER_RESTART; //restart timer
 }
 #endif
 
@@ -79,6 +83,7 @@ static int button_gpio_init(int gpio)
 	button_gpio = gpio;
 	pr_info("Init GPIO%d OK\n", button_gpio);
 	button_state = gpio_get_value(button_gpio);
+	pr_info("Got button value: %d\n", button_state);
 	button_cnt = 0;
 
 	return 0;
@@ -108,7 +113,7 @@ static int __init gpio_poll_init(void)
 		return res;
 	}
 #ifdef TIMER_ENABLE
-	timer_period = ktime_set(0, 1000000);      /*1 msec*/
+	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;
@@ -137,7 +142,7 @@ static int __init gpio_poll_init(void)
 
 static void __exit gpio_poll_exit(void)
 {
-	gpio_set_value(ledg_gpio, 0);
+	gpio_set_value(ledg_gpio, 1);
 	gpio_set_value(ledr_gpio, 0);
 	button_gpio_deinit();
 #ifdef TIMER_ENABLE

08_irq_handling/setup_orange_env.sh

@@ -0,0 +1,6 @@
+#!/bin/sh
+export ARCH=arm
+export CROSS_COMPILE='arm-buildroot-linux-uclibcgnueabihf-'
+export PATH=$PATH:~/Development/Embedded/exercise8/build_orange_image/host/bin
+export BUILD_KERNEL=/home/valenti/Development/Embedded/exercise8/build_orange_image/build/linux-5.10.10
+export CURDIR=$(pwd)