Files
Kernel-Weather-Clock/driver.c
T
2025-12-29 14:58:31 +09:00

596 lines
13 KiB
C

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/gpio.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/jiffies.h>
#include <linux/mutex.h>
#include <linux/cdev.h>
#include <linux/device.h>
#include <linux/uaccess.h>
#include <linux/rtc.h>
#include <linux/time64.h>
#include <linux/types.h>
#define DRIVER_NAME "clock_drv"
#define CLASS_NAME "clock_drv_class"
#define DS_RST 17
#define DS_DAT 4
#define DS_SCLK 22
#define ENC_S1 24
#define ENC_S2 25
#define ENC_SW 26
#define DHT_GPIO 23
#define LED0 5
#define LED1 6
#define LED2 12
#define LED3 13
#define LED4 16
#define LED5 19
#define LED6 20
#define LED7 21
static int leds[8] = {
LED0, LED1, LED2, LED3,
LED4, LED5, LED6, LED7
};
#define DEBOUNCE_MS 6
#define LONGPRESS_MS 1000
#define PAGE_DEBOUNCE_MS 200
#define DHT_CACHE_MS 2000
MODULE_LICENSE("GPL");
MODULE_AUTHOR("kkk");
MODULE_DESCRIPTION("DS1302 + rotary/button + DHT11 via /dev/clock_drv");
struct rtc_simple {
int hh, mm, ss;
int ch;
};
static DEFINE_MUTEX(lock0);
static struct rtc_simple cur;
static struct rtc_simple edit;
static bool edit_mode = false;
static int edit_field = 2;
static int ui_page = 0;
static unsigned long last_page_switch_j = 0;
static int irq_s1, irq_sw;
static unsigned long last_irq_s1, last_irq_sw;
static unsigned long sw_pressed_jiffies;
static dev_t devno;
static struct cdev cdev0;
static struct class *cls;
static int dht_temp = -1;
static int dht_hum = -1;
static unsigned long last_dht_j = 0;
static inline void ds_clk_pulse(void)
{
gpio_set_value(DS_SCLK, 1); udelay(2);
gpio_set_value(DS_SCLK, 0); udelay(2);
}
static void ds_write_byte(u8 b)
{
int i;
gpio_direction_output(DS_DAT, 0);
for (i = 0; i < 8; i++) {
gpio_set_value(DS_DAT, (b >> i) & 1);
ds_clk_pulse();
}
}
static u8 ds_read_byte(void)
{
int i;
u8 v = 0;
gpio_direction_input(DS_DAT);
for (i = 0; i < 8; i++) {
if (gpio_get_value(DS_DAT)) v |= (1 << i);
ds_clk_pulse();
}
return v;
}
static inline int bcd2int(u8 b) { return (b & 0x0F) + ((b >> 4) & 0x0F) * 10; }
static inline u8 int2bcd(int v){ return (u8)(((v/10) << 4) | (v%10)); }
static void ds1302_read_time(struct rtc_simple *t)
{
u8 sec, min, hour;
gpio_set_value(DS_SCLK, 0);
gpio_set_value(DS_RST, 1);
udelay(4);
ds_write_byte(0xBF);
sec = ds_read_byte();
min = ds_read_byte();
hour = ds_read_byte();
ds_read_byte(); ds_read_byte(); ds_read_byte(); ds_read_byte(); ds_read_byte();
gpio_set_value(DS_RST, 0);
t->ch = (sec >> 7) & 1;
t->ss = bcd2int(sec & 0x7F);
t->mm = bcd2int(min);
t->hh = bcd2int(hour & 0x3F);
}
static void ds1302_write_reg(u8 cmd, u8 data)
{
gpio_set_value(DS_SCLK, 0);
gpio_set_value(DS_RST, 1);
udelay(4);
ds_write_byte(cmd);
ds_write_byte(data);
gpio_set_value(DS_RST, 0);
}
static void ds1302_set_time(const struct rtc_simple *t)
{
ds1302_write_reg(0x8E, 0x00);
ds1302_write_reg(0x80, int2bcd(t->ss) & 0x7F);
ds1302_write_reg(0x82, int2bcd(t->mm));
ds1302_write_reg(0x84, int2bcd(t->hh));
ds1302_write_reg(0x8E, 0x80);
}
static void clamp_time(struct rtc_simple *t)
{
if (t->ss < 0) t->ss = 59;
if (t->ss > 59) t->ss = 0;
if (t->mm < 0) t->mm = 59;
if (t->mm > 59) t->mm = 0;
if (t->hh < 0) t->hh = 23;
if (t->hh > 23) t->hh = 0;
}
static const char *field_name(int f)
{
if (f == 2) return "HOUR";
if (f == 1) return "MIN";
return "SEC";
}
static int dht_wait_level(int level, int timeout_us)
{
int i;
for (i = 0; i < timeout_us; i++) {
if (gpio_get_value(DHT_GPIO) == level)
return i;
udelay(1);
}
return -ETIMEDOUT;
}
static int dht_measure_high_us(int timeout_us)
{
int i = 0;
while (gpio_get_value(DHT_GPIO) == 1) {
if (i++ >= timeout_us) return timeout_us;
udelay(1);
}
return i;
}
static int dht11_read_once(int *out_temp, int *out_hum)
{
u8 data[5] = {0};
int bit, byte;
unsigned long flags;
gpio_direction_output(DHT_GPIO, 0);
msleep(20);
gpio_set_value(DHT_GPIO, 1);
udelay(40);
gpio_direction_input(DHT_GPIO);
local_irq_save(flags);
if (dht_wait_level(0, 100) < 0) goto err;
if (dht_wait_level(1, 100) < 0) goto err;
if (dht_wait_level(0, 100) < 0) goto err;
for (bit = 0; bit < 40; bit++) {
int high_us;
if (dht_wait_level(1, 70) < 0) goto err;
high_us = dht_measure_high_us(100);
byte = bit / 8;
data[byte] <<= 1;
data[byte] |= (high_us > 40) ? 1 : 0;
(void)dht_wait_level(0, 70);
}
local_irq_restore(flags);
if (((data[0] + data[1] + data[2] + data[3]) & 0xFF) != data[4])
return -EIO;
*out_hum = data[0];
*out_temp = data[2];
return 0;
err:
local_irq_restore(flags);
return -ETIMEDOUT;
}
static void dht11_get_cached(int *out_temp, int *out_hum)
{
unsigned long now = jiffies;
if (time_after(now, last_dht_j + msecs_to_jiffies(DHT_CACHE_MS)) || last_dht_j == 0) {
int t, h;
int ret = dht11_read_once(&t, &h);
if (ret == 0) {
dht_temp = t;
dht_hum = h;
}
last_dht_j = now;
}
*out_temp = dht_temp;
*out_hum = dht_hum;
}
static void apply_delta_locked(int delta)
{
if (!edit_mode) return;
if (ui_page != 0) return;
if (edit_field == 0) edit.ss += delta;
else if (edit_field == 1) edit.mm += delta;
else edit.hh += delta;
clamp_time(&edit);
}
static void short_press_locked(void)
{
if (!edit_mode) return;
if (ui_page != 0) return;
edit_field = (edit_field == 0) ? 2 : (edit_field - 1);
}
static void long_press_action(void)
{
struct rtc_simple t;
mutex_lock(&lock0);
if (ui_page != 0) {
mutex_unlock(&lock0);
return;
}
if (!edit_mode) {
ds1302_read_time(&cur);
edit = cur;
edit_mode = true;
edit_field = 2;
mutex_unlock(&lock0);
return;
}
t = edit;
edit_mode = false;
mutex_unlock(&lock0);
ds1302_set_time(&t);
}
static void page_toggle_if_cw_locked(void)
{
unsigned long now = jiffies;
if (edit_mode) return;
if (time_before(now, last_page_switch_j + msecs_to_jiffies(PAGE_DEBOUNCE_MS)))
return;
if (gpio_get_value(ENC_S2)) {
ui_page = (ui_page + 1) % 3;
} else {
ui_page = (ui_page + 3 - 1) % 3;
}
last_page_switch_j = now;
}
static irqreturn_t s1_irq_handler(int irq, void *dev_id)
{
unsigned long now = jiffies;
if (time_before(now, last_irq_s1 + msecs_to_jiffies(DEBOUNCE_MS)))
return IRQ_HANDLED;
last_irq_s1 = now;
mutex_lock(&lock0);
if (!edit_mode) {
page_toggle_if_cw_locked();
} else {
if (gpio_get_value(ENC_S2))
apply_delta_locked(+1);
else
apply_delta_locked(-1);
}
mutex_unlock(&lock0);
return IRQ_HANDLED;
}
static irqreturn_t sw_irq_handler(int irq, void *dev_id)
{
unsigned long now = jiffies;
if (time_before(now, last_irq_sw + msecs_to_jiffies(DEBOUNCE_MS)))
return IRQ_HANDLED;
last_irq_sw = now;
if (gpio_get_value(ENC_SW) == 0) {
sw_pressed_jiffies = now;
} else {
unsigned long held_ms = jiffies_to_msecs(now - sw_pressed_jiffies);
if (held_ms >= LONGPRESS_MS) {
long_press_action();
} else {
mutex_lock(&lock0);
short_press_locked();
mutex_unlock(&lock0);
}
}
return IRQ_HANDLED;
}
static void set_led_level(int level)
{
int i;
if (level < 0) level = 0;
if (level > 8) level = 8;
for (i = 0; i < 8; i++) {
gpio_set_value(leds[i], (i < level) ? 1 : 0);
}
}
static ssize_t dev_read(struct file *f, char __user *ubuf, size_t cnt, loff_t *ppos)
{
char kbuf[160];
int len;
struct rtc_simple t;
bool mode;
int field, page;
int temp, hum;
if (*ppos > 0) return 0;
ds1302_read_time(&cur);
mutex_lock(&lock0);
mode = edit_mode;
field = edit_field;
page = ui_page;
t = (mode && page==0) ? edit : cur;
mutex_unlock(&lock0);
dht11_get_cached(&temp, &hum);
len = snprintf(kbuf, sizeof(kbuf),
"%02d:%02d:%02d MODE=%s FIELD=%s PAGE=%d TEMP=%d HUM=%d\n",
t.hh, t.mm, t.ss,
(mode && page==0) ? "EDIT" : "RUN",
field_name(field),
page,
temp, hum);
if (len > cnt) len = cnt;
if (copy_to_user(ubuf, kbuf, len)) return -EFAULT;
*ppos += len;
return len;
}
static ssize_t dev_write(struct file *f, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
char kbuf[64];
int hh, mm, ss;
int level;
if (cnt >= sizeof(kbuf))
return -EINVAL;
if (copy_from_user(kbuf, ubuf, cnt))
return -EFAULT;
kbuf[cnt] = '\0';
if (sscanf(kbuf, "LED %d", &level) == 1) {
set_led_level(level);
return cnt;
}
if (sscanf(kbuf, "SET %d:%d:%d", &hh, &mm, &ss) == 3) {
struct rtc_simple t = {
.hh = hh,
.mm = mm,
.ss = ss,
.ch = 0
};
clamp_time(&t);
ds1302_set_time(&t);
mutex_lock(&lock0);
edit_mode = false;
mutex_unlock(&lock0);
return cnt;
}
return -EINVAL;
}
static const struct file_operations fops = {
.owner = THIS_MODULE,
.read = dev_read,
.write = dev_write,
};
static int __init mod_init(void)
{
int ret;
struct timespec64 ts;
struct rtc_time tm_val;
printk(KERN_INFO "==== %s init ====\n", DRIVER_NAME);
ret = alloc_chrdev_region(&devno, 0, 1, DRIVER_NAME);
if (ret < 0) return ret;
for (int i = 0; i < 8; i++) {
gpio_request(leds[i], "led");
gpio_direction_output(leds[i], 0);
}
cdev_init(&cdev0, &fops);
ret = cdev_add(&cdev0, devno, 1);
if (ret < 0) goto err_chr;
cls = class_create(THIS_MODULE, CLASS_NAME);
if (IS_ERR(cls)) { ret = PTR_ERR(cls); goto err_cdev; }
device_create(cls, NULL, devno, NULL, DRIVER_NAME);
if (gpio_request(DS_RST,"ds_rst")||
gpio_request(DS_DAT,"ds_dat")||
gpio_request(DS_SCLK,"ds_sclk")||
gpio_request(ENC_S1,"enc_s1")||
gpio_request(ENC_S2,"enc_s2")||
gpio_request(ENC_SW,"enc_sw")||
gpio_request(DHT_GPIO,"dht11")) {
ret = -EBUSY;
goto err_dev;
}
gpio_direction_output(DS_RST,0);
gpio_direction_output(DS_SCLK,0);
gpio_direction_output(DS_DAT,0);
gpio_direction_input(ENC_S1);
gpio_direction_input(ENC_S2);
gpio_direction_input(ENC_SW);
gpio_direction_input(DHT_GPIO);
irq_s1 = gpio_to_irq(ENC_S1);
irq_sw = gpio_to_irq(ENC_SW);
ret = request_irq(irq_s1,s1_irq_handler,IRQF_TRIGGER_FALLING,"enc_s1_irq",NULL);
if (ret) goto err_gpio;
ret = request_irq(irq_sw,sw_irq_handler,
IRQF_TRIGGER_FALLING|IRQF_TRIGGER_RISING,
"enc_sw_irq",NULL);
if (ret) { free_irq(irq_s1,NULL); goto err_gpio; }
ds1302_read_time(&cur);
if (cur.ch==1) {
ds1302_set_time(&cur);
ds1302_read_time(&cur);
}
ktime_get_real_ts64(&ts);
rtc_time64_to_tm(ts.tv_sec,&tm_val);
mutex_lock(&lock0);
cur.hh = (tm_val.tm_hour+24-3)%24;
cur.mm = tm_val.tm_min;
cur.ss = tm_val.tm_sec;
cur.ch = 0;
ds1302_set_time(&cur);
edit = cur;
edit_mode = false;
edit_field = 2;
ui_page = 0;
mutex_unlock(&lock0);
printk(KERN_INFO "OK: DHT cached every %d ms\n", DHT_CACHE_MS);
return 0;
err_gpio:
gpio_free(DHT_GPIO);
gpio_free(ENC_SW); gpio_free(ENC_S2); gpio_free(ENC_S1);
gpio_free(DS_SCLK); gpio_free(DS_DAT); gpio_free(DS_RST);
err_dev:
device_destroy(cls,devno);
class_destroy(cls);
err_cdev:
cdev_del(&cdev0);
err_chr:
unregister_chrdev_region(devno,1);
return ret;
}
static void __exit mod_exit(void)
{
free_irq(irq_s1,NULL);
free_irq(irq_sw,NULL);
gpio_free(DHT_GPIO);
gpio_free(ENC_SW); gpio_free(ENC_S2); gpio_free(ENC_S1);
gpio_free(DS_SCLK); gpio_free(DS_DAT); gpio_free(DS_RST);
for (int i = 0; i < 8; i++)
gpio_free(leds[i]);
device_destroy(cls,devno);
class_destroy(cls);
cdev_del(&cdev0);
unregister_chrdev_region(devno,1);
printk(KERN_INFO "==== %s exit ====\n", DRIVER_NAME);
}
module_init(mod_init);
module_exit(mod_exit);