HYM8563驱动分析
从rk3188下摘录出来的hym8563源码
/*drivers/rtc/rtc-HYM8563.h - driver for HYM8563
*
* Copyright (C) 2010 ROCKCHIP, Inc.
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#ifndef _DRIVERS_HYM8563_H
#define _DRIVERS_HYM8563_H
#define RTC_CTL1 0x00
#define RTC_CTL2 0x01
#define RTC_SEC 0x02
#define RTC_MIN 0x03
#define RTC_HOUR 0x04
#define RTC_DAY 0x05
#define RTC_WEEK 0x06
#define RTC_MON 0x07
#define RTC_YEAR 0x08
#define RTC_A_MIN 0x09
#define RTC_A_HOUR 0x0A
#define RTC_A_DAY 0x0B
#define RTC_A_WEEK 0x0C
#define RTC_CLKOUT 0x0D
#define RTC_T_CTL 0x0E
#define RTC_T_COUNT 0x0F
#define CENTURY 0x80
#define TI 0x10
#define AF 0x08
#define TF 0x04
#define AIE 0x02
#define TIE 0x01
#define FE 0x80
#define TE 0x80
#define FD1 0x02
#define FD0 0x01
#define TD1 0x02
#define TD0 0x01
#define VL 0x80
#define HYM8563_REG_LEN 0x10
#define HYM8563_RTC_SECTION_LEN 0x07
struct hym8563_platform_data {
unsigned int speed;
unsigned int mode;
unsigned int reg_byte_cnt;
};
#endif /*_DRIVERS_HYM8563_H*/#include
// ret = hym8563_i2c_set_regs(client, RTC_SEC+i, ®s[i], 1);
// }
hym8563_i2c_set_regs(client, RTC_SEC, regs, HYM8563_RTC_SECTION_LEN);
mutex_unlock(&hym8563->mutex);
return 0;
}
static int hym8563_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
return hym8563_set_time(to_i2c_client(dev), tm);
}
static int hym8563_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *tm)
{
struct i2c_client *client = to_i2c_client(dev);
struct hym8563 *hym8563 = i2c_get_clientdata(client);
u8 regs[4] = { 0, };
pr_debug("enter\n");
mutex_lock(&hym8563->mutex);
hym8563_i2c_read_regs(client, RTC_A_MIN, regs, 4);
regs[0] = 0x0;
regs[0] |= TIE;
hym8563_i2c_set_regs(client, RTC_CTL2, regs, 1);
mutex_unlock(&hym8563->mutex);
return 0;
}
static int hym8563_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
struct i2c_client *client = to_i2c_client(dev);
struct hym8563 *hym8563 = i2c_get_clientdata(client);
struct rtc_time now, *tm = &alarm->time;
u8 regs[4] = { 0, };
u8 mon_day;
unsigned long alarm_sec, now_sec;
int diff_sec = 0;
pr_debug("%4d-%02d-%02d(%d) %02d:%02d:%02d enabled %d\n",
1900 + tm->tm_year, tm->tm_mon + 1, tm->tm_mday, tm->tm_wday,
tm->tm_hour, tm->tm_min, tm->tm_sec, alarm->enabled);
hym8563_read_datetime(client, &now);
mutex_lock(&hym8563->mutex);
rtc_tm_to_time(tm, &alarm_sec);
rtc_tm_to_time(&now, &now_sec);
diff_sec = alarm_sec - now_sec;
if((diff_sec > 0) && (diff_sec < 256))
{
printk("%s:diff_sec= %ds , use time\n",__func__, diff_sec);
hym8563_enable_count(client, 1);
hym8563_set_count(client, diff_sec);
}
else
{
printk("%s:diff_sec= %ds , use alarm\n",__func__, diff_sec);
hym8563_enable_count(client, 0);
if(tm->tm_sec > 0)
{
rtc_tm_to_time(tm, &alarm_sec);
rtc_time_to_tm(alarm_sec, tm);
}
hym8563->alarm = *alarm;
regs[0] = 0x0;
hym8563_i2c_set_regs(client, RTC_CTL2, regs, 1);
mon_day = rtc_month_days(tm->tm_mon, tm->tm_year + 1900);
hym8563_i2c_read_regs(client, RTC_A_MIN, regs, 4);
if (tm->tm_min >= 60 || tm->tm_min < 0) //set min
regs[0x00] = bin2bcd(0x00) & 0x7f;
else
regs[0x00] = bin2bcd(tm->tm_min) & 0x7f;
if (tm->tm_hour >= 24 || tm->tm_hour < 0) //set hour
regs[0x01] = bin2bcd(0x00) & 0x7f;
else
regs[0x01] = bin2bcd(tm->tm_hour) & 0x7f;
regs[0x03] = bin2bcd (tm->tm_wday) & 0x7f;
/* if the input month day is bigger than the biggest day of this month, set the biggest day */
if (tm->tm_mday > mon_day)
regs[0x02] = bin2bcd(mon_day) & 0x7f;
else if (tm->tm_mday > 0)
regs[0x02] = bin2bcd(tm->tm_mday) & 0x7f;
else if (tm->tm_mday <= 0)
regs[0x02] = bin2bcd(0x01) & 0x7f;
hym8563_i2c_set_regs(client, RTC_A_MIN, regs, 4);
hym8563_i2c_read_regs(client, RTC_A_MIN, regs, 4);
hym8563_i2c_read_regs(client, RTC_CTL2, regs, 1);
if (alarm->enabled == 1)
regs[0] |= AIE;
else
regs[0] &= 0x0;
regs[0] |= TIE;
hym8563_i2c_set_regs(client, RTC_CTL2, regs, 1);
hym8563_i2c_read_regs(client, RTC_CTL2, regs, 1);
if(diff_sec <= 0)
{
pr_info("alarm sec <= now sec\n");
}
}
mutex_unlock(&hym8563->mutex);
return 0;
}
#if defined(CONFIG_RTC_INTF_DEV) || defined(CONFIG_RTC_INTF_DEV_MODULE)
static int hym8563_i2c_open_alarm(struct i2c_client *client)
{
u8 data;
hym8563_i2c_read_regs(client, RTC_CTL2, &data, 1);
data |= AIE;
hym8563_i2c_set_regs(client, RTC_CTL2, &data, 1);
return 0;
}
static int hym8563_i2c_close_alarm(struct i2c_client *client)
{
u8 data;
hym8563_i2c_read_regs(client, RTC_CTL2, &data, 1);
data &= ~AIE;
hym8563_i2c_set_regs(client, RTC_CTL2, &data, 1);
return 0;
}
static int hym8563_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
{
struct i2c_client *client = to_i2c_client(dev);
switch (cmd) {
case RTC_AIE_OFF:
if(hym8563_i2c_close_alarm(client) < 0)
goto err;
break;
case RTC_AIE_ON:
if(hym8563_i2c_open_alarm(client))
goto err;
break;
default:
return -ENOIOCTLCMD;
}
return 0;
err:
return -EIO;
}
#else
#define hym8563_rtc_ioctl NULL
#endif
#if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE)
static int hym8563_rtc_proc(struct device *dev, struct seq_file *seq)
{
return 0;
}
#else
#define hym8563_rtc_proc NULL
#endif
static irqreturn_t hym8563_wakeup_irq(int irq, void *data)
{
struct hym8563 *hym8563 = data;
struct i2c_client *client = hym8563->client;
u8 value;
mutex_lock(&hym8563->mutex);
hym8563_i2c_read_regs(client, RTC_CTL2, &value, 1);
value &= ~(AF|TF);
hym8563_i2c_set_regs(client, RTC_CTL2, &value, 1);
mutex_unlock(&hym8563->mutex);
rtc_update_irq(hym8563->rtc, 1, RTC_IRQF | RTC_AF | RTC_UF);
//printk("%s:irq=%d\n",__func__,irq);
return IRQ_HANDLED;
}
static const struct rtc_class_ops hym8563_rtc_ops = {
.read_time = hym8563_rtc_read_time,
.set_time = hym8563_rtc_set_time,
.read_alarm = hym8563_rtc_read_alarm,
.set_alarm = hym8563_rtc_set_alarm,
.ioctl = hym8563_rtc_ioctl,
.proc = hym8563_rtc_proc
};
static int __devinit hym8563_probe(struct i2c_client *client, const struct i2c_device_id *id)
{
int rc = 0;
u8 reg = 0;
struct hym8563 *hym8563;
struct rtc_device *rtc = NULL;
struct rtc_time tm_read, tm = {
.tm_wday = 6,
.tm_year = 111,
.tm_mon = 0,
.tm_mday = 1,
.tm_hour = 12,
.tm_min = 0,
.tm_sec = 0,
};
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
return -ENODEV;
hym8563 = kzalloc(sizeof(struct hym8563), GFP_KERNEL);
if (!hym8563) {
return -ENOMEM;
}
gClient = client;
hym8563->client = client;
hym8563->alarm.enabled = 0;
mutex_init(&hym8563->mutex);
wake_lock_init(&hym8563->wake_lock, WAKE_LOCK_SUSPEND, "rtc_hym8563");
i2c_set_clientdata(client, hym8563);
hym8563_init_device(client); //时钟模块初始化
hym8563_enable_count(client, 0);//关闭计时
// check power down
hym8563_i2c_read_regs(client,RTC_SEC,®,1);
if (reg&0x80) {
dev_info(&client->dev, "clock/calendar information is no longer guaranteed\n");
hym8563_set_time(client, &tm);
}
hym8563_read_datetime(client, &tm_read); //read time from hym8563
if(((tm_read.tm_year < 70) | (tm_read.tm_year > 137 )) | (tm_read.tm_mon == -1) | (rtc_valid_tm(&tm_read) != 0)) //if the hym8563 haven't initialized
{
hym8563_set_time(client, &tm); //initialize the hym8563
}
if(gpio_request(client->irq, "rtc gpio"))
{
dev_err(&client->dev, "gpio request fail\n");
gpio_free(client->irq);
goto exit;
}
hym8563->irq = gpio_to_irq(client->irq);
gpio_pull_updown(client->irq,GPIOPullUp);
if (request_threaded_irq(hym8563->irq, NULL, hym8563_wakeup_irq, IRQF_TRIGGER_LOW | IRQF_ONESHOT, client->dev.driver->name, hym8563) < 0)
{
printk("unable to request rtc irq\n");
goto exit;
}
enable_irq_wake(hym8563->irq);
rtc = rtc_device_register(client->name, &client->dev,
&hym8563_rtc_ops, THIS_MODULE);
if (IS_ERR(rtc)) {
rc = PTR_ERR(rtc);
rtc = NULL;
goto exit;
}
hym8563->rtc = rtc;
return 0;
exit:
if (rtc)
rtc_device_unregister(rtc);
if (hym8563) {
wake_lock_destroy(&hym8563->wake_lock);
kfree(hym8563);
}
return rc;
}
static int __devexit hym8563_remove(struct i2c_client *client)
{
struct hym8563 *hym8563 = i2c_get_clientdata(client);
if (hym8563->irq > 0) {
mutex_lock(&hym8563->mutex);
hym8563->exiting = 1;
mutex_unlock(&hym8563->mutex);
free_irq(hym8563->irq, hym8563);
cancel_work_sync(&hym8563->work);
}
rtc_device_unregister(hym8563->rtc);
wake_lock_destroy(&hym8563->wake_lock);
kfree(hym8563);
hym8563 = NULL;
return 0;
}
void hym8563_shutdown(struct i2c_client * client)
{ u8 regs[2];
int ret;
//disable clkout
regs[0] = 0x00;
ret=hym8563_i2c_set_regs(client, RTC_CLKOUT, regs, 1);
if(ret<0)
printk("rtc shutdown is error\n");
}
static const struct i2c_device_id hym8563_id[] = {
{ "rtc_hym8563", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, hym8563_id);
//构建i2c_driver
static struct i2c_driver hym8563_driver = {
.driver = {
.name = "rtc_hym8563",
.owner = THIS_MODULE,
},
.probe = hym8563_probe,
.remove = __devexit_p(hym8563_remove),
#if defined(CONFIG_ARCH_RK3066B) || defined(CONFIG_ARCH_RK3188) || defined(CONFIG_ARCH_RKPX3)
//.shutdown=hym8563_shutdown,
#else
.shutdown=hym8563_shutdown,
#endif
.id_table = hym8563_id,
};
//注册i2c_driver
static int __init hym8563_init(void)
{
return i2c_add_driver(&hym8563_driver);
}
static void __exit hym8563_exit(void)
{
i2c_del_driver(&hym8563_driver);
}
MODULE_AUTHOR("lhh [email protected]");
MODULE_DESCRIPTION("HYM8563 RTC driver");
MODULE_LICENSE("GPL");
module_init(hym8563_init);
module_exit(hym8563_exit); 关于IIC驱动的介绍，可查阅
http://www.cnblogs.com/liugf05/archive/2012/12/05/2803795.html
http://www.cnblogs.com/simonshi/archive/2011/02/24/1963426.html
某些关键函数分析
注册平台驱动的函数为platform_driver_register()详见
http://blog.csdn.net/yili_xie/article/details/5193609
对应IIC设备，对应的注册IIC驱动的函数为i2c_add_driver();
http://blog.csdn.net/zclongembedded/article/details/8207722
i2c_check_functionality用来判定设配器的能力
wake_lock_init()用于初始化一个新锁，type参数指定了锁的类型,详看
http://blog.csdn.net/g_salamander/article/details/7978772
gpio_request(client->irq, “rtc gpio”)//申请该gpio，并设置名字为rtc gpio
hym8563->irq = gpio_to_irq(client->irq);//将申请到的io口设置中断功能
gpio_pull_updown(client->irq,GPIOPullUp);//上拉该gpio。
该gpio在板级文件kernel/arm/mach-rkpx3/board-rkpx3-sdk. c中定义。
static struct i2c_board_info __initdata i2c1_info[] = {
#if defined (CONFIG_RTC_HYM8563)
{
.type = "rtc_hym8563",
.addr = 0x51,
.flags = 0,
.irq = RK30_PIN0_PB5,
},
#endif
}
i2c_register_board_info(1, i2c1_info, ARRAY_SIZE(i2c1_info));
}request_threaded_irq申请线程中断，为什么不用request_irq,请查阅
http://www.cnblogs.com/leaven/archive/2010/09/09/1822018.html
request_threaded_irq(hym8563->irq, NULL, hym8563_wakeup_irq, IRQF_TRIGGER_LOW | IRQF_ONESHOT, client->dev.driver->name, hym8563)
RQF_TRIGGER_LOW电平触发，IRQF_ONESHOT代表只触发一次，详细介绍见
http://www.wowotech.net/linux_kenrel/request_threaded_irq.html
static irqreturn_t hym8563_wakeup_irq(int irq, void *data)
{
struct hym8563 *hym8563 = data;
struct i2c_client *client = hym8563->client;
u8 value;
mutex_lock(&hym8563->mutex);
hym8563_i2c_read_regs(client, RTC_CTL2, &value, 1);
value &= ~(AF|TF);
hym8563_i2c_set_regs(client, RTC_CTL2, &value, 1);
mutex_unlock(&hym8563->mutex);
rtc_update_irq(hym8563->rtc, 1, RTC_IRQF | RTC_AF | RTC_UF);
//printk("%s:irq=%d\n",__func__,irq);
return IRQ_HANDLED;
}enable_irq_wake(hym8563->irq);//时能中断唤醒
我的理解是当我们设好闹钟后，关闭屏幕（休眠），时间到了触发了中断，开屏幕响铃。
详见http://blog.csdn.net/njuitjf/article/details/21475405
rtc=rtc_device_register(client->name, &client->dev,&hym8563_rtc_ops, THIS_MODULE);//向linux系统注册RTC设备，并成生proc、sys目录下的属性文件
详见http://blog.csdn.net/fanqipin/article/details/8089995
