From cf044f0ed526752b8c2aaae748220759608b3fc8 Mon Sep 17 00:00:00 2001 From: Ryan Mallon Date: Tue, 22 Mar 2011 16:34:53 -0700 Subject: drivers/rtc/rtc-isl1208.c: add alarm support Add alarm/wakeup support to rtc isl1208 driver Signed-off-by: Ryan Mallon Cc: Alessandro Zummo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/rtc/rtc-isl1208.c | 176 ++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 171 insertions(+), 5 deletions(-) diff --git a/drivers/rtc/rtc-isl1208.c b/drivers/rtc/rtc-isl1208.c index 468200c38ecb..da8beb8cae51 100644 --- a/drivers/rtc/rtc-isl1208.c +++ b/drivers/rtc/rtc-isl1208.c @@ -39,6 +39,8 @@ #define ISL1208_REG_SR_BAT (1<<1) /* battery */ #define ISL1208_REG_SR_RTCF (1<<0) /* rtc fail */ #define ISL1208_REG_INT 0x08 +#define ISL1208_REG_INT_ALME (1<<6) /* alarm enable */ +#define ISL1208_REG_INT_IM (1<<7) /* interrupt/alarm mode */ #define ISL1208_REG_09 0x09 /* reserved */ #define ISL1208_REG_ATR 0x0a #define ISL1208_REG_DTR 0x0b @@ -201,6 +203,30 @@ isl1208_i2c_set_usr(struct i2c_client *client, u16 usr) ISL1208_USR_SECTION_LEN); } +static int +isl1208_rtc_toggle_alarm(struct i2c_client *client, int enable) +{ + int icr = i2c_smbus_read_byte_data(client, ISL1208_REG_INT); + + if (icr < 0) { + dev_err(&client->dev, "%s: reading INT failed\n", __func__); + return icr; + } + + if (enable) + icr |= ISL1208_REG_INT_ALME | ISL1208_REG_INT_IM; + else + icr &= ~(ISL1208_REG_INT_ALME | ISL1208_REG_INT_IM); + + icr = i2c_smbus_write_byte_data(client, ISL1208_REG_INT, icr); + if (icr < 0) { + dev_err(&client->dev, "%s: writing INT failed\n", __func__); + return icr; + } + + return 0; +} + static int isl1208_rtc_proc(struct device *dev, struct seq_file *seq) { @@ -288,9 +314,8 @@ isl1208_i2c_read_alarm(struct i2c_client *client, struct rtc_wkalrm *alarm) { struct rtc_time *const tm = &alarm->time; u8 regs[ISL1208_ALARM_SECTION_LEN] = { 0, }; - int sr; + int icr, yr, sr = isl1208_i2c_get_sr(client); - sr = isl1208_i2c_get_sr(client); if (sr < 0) { dev_err(&client->dev, "%s: reading SR failed\n", __func__); return sr; @@ -313,6 +338,73 @@ isl1208_i2c_read_alarm(struct i2c_client *client, struct rtc_wkalrm *alarm) bcd2bin(regs[ISL1208_REG_MOA - ISL1208_REG_SCA] & 0x1f) - 1; tm->tm_wday = bcd2bin(regs[ISL1208_REG_DWA - ISL1208_REG_SCA] & 0x03); + /* The alarm doesn't store the year so get it from the rtc section */ + yr = i2c_smbus_read_byte_data(client, ISL1208_REG_YR); + if (yr < 0) { + dev_err(&client->dev, "%s: reading RTC YR failed\n", __func__); + return yr; + } + tm->tm_year = bcd2bin(yr) + 100; + + icr = i2c_smbus_read_byte_data(client, ISL1208_REG_INT); + if (icr < 0) { + dev_err(&client->dev, "%s: reading INT failed\n", __func__); + return icr; + } + alarm->enabled = !!(icr & ISL1208_REG_INT_ALME); + + return 0; +} + +static int +isl1208_i2c_set_alarm(struct i2c_client *client, struct rtc_wkalrm *alarm) +{ + struct rtc_time *alarm_tm = &alarm->time; + u8 regs[ISL1208_ALARM_SECTION_LEN] = { 0, }; + const int offs = ISL1208_REG_SCA; + unsigned long rtc_secs, alarm_secs; + struct rtc_time rtc_tm; + int err, enable; + + err = isl1208_i2c_read_time(client, &rtc_tm); + if (err) + return err; + err = rtc_tm_to_time(&rtc_tm, &rtc_secs); + if (err) + return err; + err = rtc_tm_to_time(alarm_tm, &alarm_secs); + if (err) + return err; + + /* If the alarm time is before the current time disable the alarm */ + if (!alarm->enabled || alarm_secs <= rtc_secs) + enable = 0x00; + else + enable = 0x80; + + /* Program the alarm and enable it for each setting */ + regs[ISL1208_REG_SCA - offs] = bin2bcd(alarm_tm->tm_sec) | enable; + regs[ISL1208_REG_MNA - offs] = bin2bcd(alarm_tm->tm_min) | enable; + regs[ISL1208_REG_HRA - offs] = bin2bcd(alarm_tm->tm_hour) | + ISL1208_REG_HR_MIL | enable; + + regs[ISL1208_REG_DTA - offs] = bin2bcd(alarm_tm->tm_mday) | enable; + regs[ISL1208_REG_MOA - offs] = bin2bcd(alarm_tm->tm_mon + 1) | enable; + regs[ISL1208_REG_DWA - offs] = bin2bcd(alarm_tm->tm_wday & 7) | enable; + + /* write ALARM registers */ + err = isl1208_i2c_set_regs(client, offs, regs, + ISL1208_ALARM_SECTION_LEN); + if (err < 0) { + dev_err(&client->dev, "%s: writing ALARM section failed\n", + __func__); + return err; + } + + err = isl1208_rtc_toggle_alarm(client, enable); + if (err) + return err; + return 0; } @@ -391,12 +483,63 @@ isl1208_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) return isl1208_i2c_read_alarm(to_i2c_client(dev), alarm); } +static int +isl1208_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) +{ + return isl1208_i2c_set_alarm(to_i2c_client(dev), alarm); +} + +static irqreturn_t +isl1208_rtc_interrupt(int irq, void *data) +{ + unsigned long timeout = jiffies + msecs_to_jiffies(1000); + struct i2c_client *client = data; + int handled = 0, sr, err; + + /* + * I2C reads get NAK'ed if we read straight away after an interrupt? + * Using a mdelay/msleep didn't seem to help either, so we work around + * this by continually trying to read the register for a short time. + */ + while (1) { + sr = isl1208_i2c_get_sr(client); + if (sr >= 0) + break; + + if (time_after(jiffies, timeout)) { + dev_err(&client->dev, "%s: reading SR failed\n", + __func__); + return sr; + } + } + + if (sr & ISL1208_REG_SR_ALM) { + dev_dbg(&client->dev, "alarm!\n"); + + /* Clear the alarm */ + sr &= ~ISL1208_REG_SR_ALM; + sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR, sr); + if (sr < 0) + dev_err(&client->dev, "%s: writing SR failed\n", + __func__); + else + handled = 1; + + /* Disable the alarm */ + err = isl1208_rtc_toggle_alarm(client, 0); + if (err) + return err; + } + + return handled ? IRQ_HANDLED : IRQ_NONE; +} + static const struct rtc_class_ops isl1208_rtc_ops = { .proc = isl1208_rtc_proc, .read_time = isl1208_rtc_read_time, .set_time = isl1208_rtc_set_time, .read_alarm = isl1208_rtc_read_alarm, - /*.set_alarm = isl1208_rtc_set_alarm, */ + .set_alarm = isl1208_rtc_set_alarm, }; /* sysfs interface */ @@ -488,11 +631,29 @@ isl1208_probe(struct i2c_client *client, const struct i2c_device_id *id) dev_info(&client->dev, "chip found, driver version " DRV_VERSION "\n"); + if (client->irq > 0) { + rc = request_threaded_irq(client->irq, NULL, + isl1208_rtc_interrupt, + IRQF_SHARED, + isl1208_driver.driver.name, client); + if (!rc) { + device_init_wakeup(&client->dev, 1); + enable_irq_wake(client->irq); + } else { + dev_err(&client->dev, + "Unable to request irq %d, no alarm support\n", + client->irq); + client->irq = 0; + } + } + rtc = rtc_device_register(isl1208_driver.driver.name, &client->dev, &isl1208_rtc_ops, THIS_MODULE); - if (IS_ERR(rtc)) - return PTR_ERR(rtc); + if (IS_ERR(rtc)) { + rc = PTR_ERR(rtc); + goto exit_free_irq; + } i2c_set_clientdata(client, rtc); @@ -514,6 +675,9 @@ isl1208_probe(struct i2c_client *client, const struct i2c_device_id *id) exit_unregister: rtc_device_unregister(rtc); +exit_free_irq: + if (client->irq) + free_irq(client->irq, client); return rc; } @@ -525,6 +689,8 @@ isl1208_remove(struct i2c_client *client) sysfs_remove_group(&client->dev.kobj, &isl1208_rtc_sysfs_files); rtc_device_unregister(rtc); + if (client->irq) + free_irq(client->irq, client); return 0; } -- cgit v1.2.3-55-g7522