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authorRyan Mallon <ryan@bluewatersys.com>2011-03-22 16:34:53 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-03-22 17:44:16 -0700
commitcf044f0ed526752b8c2aaae748220759608b3fc8 (patch)
treebafd4c7abaed6fa03c5314d59f6de79a639a5008 /drivers/rtc
parentbc96ba7414ca4456661d0873856e0f363d32ba67 (diff)
downloadlinux-cf044f0ed526752b8c2aaae748220759608b3fc8.tar.bz2
drivers/rtc/rtc-isl1208.c: add alarm support
Add alarm/wakeup support to rtc isl1208 driver Signed-off-by: Ryan Mallon <ryan@bluewatersys.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/rtc')
-rw-r--r--drivers/rtc/rtc-isl1208.c176
1 files 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
@@ -202,6 +204,30 @@ isl1208_i2c_set_usr(struct i2c_client *client, u16 usr)
}
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)
{
struct i2c_client *const client = to_i2c_client(dev);
@@ -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;
}