@@ -154,6 +154,7 @@ static const struct chip_desc chips[last_ds_type] = {
.alarm = 1,
},
[mcp7941x] = {
+ .alarm = 1,
/* this is battery backed SRAM */
.nvram_offset = 0x20,
.nvram_size = 0x40,
@@ -606,6 +607,178 @@ static const struct rtc_class_ops ds13xx_rtc_ops = {
/*----------------------------------------------------------------------*/
+/*
+ * Alarm support for mcp7941x devices.
+ */
+
+#define MCP7941X_REG_CONTROL 0x07
+# define MCP7941X_BIT_ALM0_EN 0x10
+# define MCP7941X_BIT_ALM1_EN 0x20
+#define MCP7941X_REG_ALARM0_BASE 0x0a
+#define MCP7941X_REG_ALARM0_CTRL 0x0d
+#define MCP7941X_REG_ALARM1_BASE 0x11
+#define MCP7941X_REG_ALARM1_CTRL 0x14
+# define MCP7941X_BIT_ALMX_IF (1 << 3)
+# define MCP7941X_BIT_ALMX_C0 (1 << 4)
+# define MCP7941X_BIT_ALMX_C1 (1 << 5)
+# define MCP7941X_BIT_ALMX_C2 (1 << 6)
+# define MCP7941X_BIT_ALMX_POL (1 << 7)
+# define MCP7941X_MSK_ALMX_MATCH (MCP7941X_BIT_ALMX_C0 | \
+ MCP7941X_BIT_ALMX_C1 | \
+ MCP7941X_BIT_ALMX_C2)
+
+static void mcp7941x_work(struct work_struct *work)
+{
+ struct ds1307 *ds1307 = container_of(work, struct ds1307, work);
+ struct i2c_client *client = ds1307->client;
+ int reg, ret;
+
+ mutex_lock(&ds1307->rtc->ops_lock);
+
+ /* Check and clear alarm 0 interrupt flag. */
+ reg = i2c_smbus_read_byte_data(client, MCP7941X_REG_ALARM0_CTRL);
+ if (reg < 0)
+ goto out;
+ if (!(reg & MCP7941X_BIT_ALMX_IF))
+ goto out;
+ reg &= ~MCP7941X_BIT_ALMX_IF;
+ ret = i2c_smbus_write_byte_data(client, MCP7941X_REG_ALARM0_CTRL, reg);
+ if (ret < 0)
+ goto out;
+
+ /* Disable alarm 0. */
+ reg = i2c_smbus_read_byte_data(client, MCP7941X_REG_CONTROL);
+ if (reg < 0)
+ goto out;
+ reg &= ~MCP7941X_BIT_ALM0_EN;
+ ret = i2c_smbus_write_byte_data(client, MCP7941X_REG_CONTROL, reg);
+ if (ret < 0)
+ goto out;
+
+ rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF);
+
+out:
+ if (test_bit(HAS_ALARM, &ds1307->flags))
+ enable_irq(client->irq);
+ mutex_unlock(&ds1307->rtc->ops_lock);
+}
+
+static int mcp7941x_read_alarm(struct device *dev, struct rtc_wkalrm *t)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct ds1307 *ds1307 = i2c_get_clientdata(client);
+ u8 *regs = ds1307->regs;
+ int ret;
+
+ if (!test_bit(HAS_ALARM, &ds1307->flags))
+ return -EINVAL;
+
+ /* Read control and alarm 0 registers. */
+ ret = ds1307->read_block_data(client, MCP7941X_REG_CONTROL, 10, regs);
+ if (ret < 0)
+ return ret;
+
+ t->enabled = !!(regs[0] & MCP7941X_BIT_ALM0_EN);
+
+ /* Report alarm 0 time assuming 24-hour and day-of-month modes. */
+ t->time.tm_sec = bcd2bin(ds1307->regs[3] & 0x7f);
+ t->time.tm_min = bcd2bin(ds1307->regs[4] & 0x7f);
+ t->time.tm_hour = bcd2bin(ds1307->regs[5] & 0x3f);
+ t->time.tm_wday = bcd2bin(ds1307->regs[6] & 0x7) - 1;
+ t->time.tm_mday = bcd2bin(ds1307->regs[7] & 0x3f);
+ t->time.tm_mon = bcd2bin(ds1307->regs[8] & 0x1f) - 1;
+ t->time.tm_year = -1;
+ t->time.tm_yday = -1;
+ t->time.tm_isdst = -1;
+
+ dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d "
+ "enabled=%d polarity=%d irq=%d match=%d\n", __func__,
+ t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
+ t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, t->enabled,
+ !!(ds1307->regs[6] & MCP7941X_BIT_ALMX_POL),
+ !!(ds1307->regs[6] & MCP7941X_BIT_ALMX_IF),
+ (ds1307->regs[6] & MCP7941X_MSK_ALMX_MATCH) >> 4);
+
+ return 0;
+}
+
+static int mcp7941x_set_alarm(struct device *dev, struct rtc_wkalrm *t)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct ds1307 *ds1307 = i2c_get_clientdata(client);
+ unsigned char *regs = ds1307->regs;
+ int ret;
+
+ if (!test_bit(HAS_ALARM, &ds1307->flags))
+ return -EINVAL;
+
+ dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d "
+ "enabled=%d pending=%d\n", __func__,
+ t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
+ t->time.tm_wday, t->time.tm_mday, t->time.tm_mon,
+ t->enabled, t->pending);
+
+ /* Read control and alarm 0 registers. */
+ ret = ds1307->read_block_data(client, MCP7941X_REG_CONTROL, 10, regs);
+ if (ret < 0)
+ return ret;
+
+ /* Set alarm 0, using 24-hour and day-of-month modes. */
+ regs[3] = bin2bcd(t->time.tm_sec);
+ regs[4] = bin2bcd(t->time.tm_min);
+ regs[5] = bin2bcd(t->time.tm_hour);
+ regs[6] = bin2bcd(t->time.tm_wday) + 1;
+ regs[7] = bin2bcd(t->time.tm_mday);
+ regs[8] = bin2bcd(t->time.tm_mon) + 1;
+
+ /* Clear the alarm 0 interrupt flag. */
+ regs[6] &= ~MCP7941X_BIT_ALMX_IF;
+ /* Set alarm match: second, minute, hour, day, date, month. */
+ regs[6] |= MCP7941X_MSK_ALMX_MATCH;
+
+ if (t->enabled)
+ regs[0] |= MCP7941X_BIT_ALM0_EN;
+ else
+ regs[0] &= ~MCP7941X_BIT_ALM0_EN;
+
+ ret = ds1307->write_block_data(client, MCP7941X_REG_CONTROL, 10, regs);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int mcp7941x_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct ds1307 *ds1307 = i2c_get_clientdata(client);
+ int reg;
+
+ if (!test_bit(HAS_ALARM, &ds1307->flags))
+ return -EINVAL;
+
+ reg = i2c_smbus_read_byte_data(client, MCP7941X_REG_CONTROL);
+ if (reg < 0)
+ return reg;
+
+ if (enabled)
+ reg |= MCP7941X_BIT_ALM0_EN;
+ else
+ reg &= ~MCP7941X_BIT_ALM0_EN;
+
+ return i2c_smbus_write_byte_data(client, MCP7941X_REG_CONTROL, reg);
+}
+
+static const struct rtc_class_ops mcp7941x_rtc_ops = {
+ .read_time = ds1307_get_time,
+ .set_time = ds1307_set_time,
+ .read_alarm = mcp7941x_read_alarm,
+ .set_alarm = mcp7941x_set_alarm,
+ .alarm_irq_enable = mcp7941x_alarm_irq_enable,
+};
+
+/*----------------------------------------------------------------------*/
+
static ssize_t
ds1307_nvram_read(struct file *filp, struct kobject *kobj,
struct bin_attribute *attr,
@@ -678,6 +851,7 @@ static int ds1307_probe(struct i2c_client *client,
[ds_1339] = DS1339_BIT_BBSQI,
[ds_3231] = DS3231_BIT_BBSQW,
};
+ const struct rtc_class_ops *rtc_ops = &ds13xx_rtc_ops;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)
&& !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_I2C_BLOCK))
@@ -816,6 +990,13 @@ static int ds1307_probe(struct i2c_client *client,
case ds_1388:
ds1307->offset = 1; /* Seconds starts at 1 */
break;
+ case mcp7941x:
+ rtc_ops = &mcp7941x_rtc_ops;
+ if (ds1307->client->irq > 0 && chip->alarm) {
+ INIT_WORK(&ds1307->work, mcp7941x_work);
+ want_irq = true;
+ }
+ break;
default:
break;
}
@@ -929,7 +1110,7 @@ read_rtc:
device_set_wakeup_capable(&client->dev, want_irq);
ds1307->rtc = devm_rtc_device_register(&client->dev, client->name,
- &ds13xx_rtc_ops, THIS_MODULE);
+ rtc_ops, THIS_MODULE);
if (IS_ERR(ds1307->rtc)) {
err = PTR_ERR(ds1307->rtc);
dev_err(&client->dev,
This patch adds alarm support for the Microchip RTC devices MCP794xx. Note that two programmable alarms are provided by the chip but only one is used by the driver. Signed-off-by: Simon Guinot <simon.guinot@sequanux.org> --- drivers/rtc/rtc-ds1307.c | 183 ++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 182 insertions(+), 1 deletion(-)