diff options
Diffstat (limited to 'drivers/rtc/rtc-ds1307.c')
-rw-r--r-- | drivers/rtc/rtc-ds1307.c | 183 |
1 files changed, 182 insertions, 1 deletions
diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c index f739be96cbc0..f03d5ba96db1 100644 --- a/drivers/rtc/rtc-ds1307.c +++ b/drivers/rtc/rtc-ds1307.c @@ -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)) { return PTR_ERR(ds1307->rtc); } |