aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/rtc/rtc-ds1307.c
diff options
context:
space:
mode:
authorUwe Kleine-König <u.kleine-koenig@pengutronix.de>2019-01-25 15:35:55 +0100
committerAlexandre Belloni <alexandre.belloni@bootlin.com>2019-02-07 20:55:41 +0100
commitd0e3f61b08e222d3c6895085487cbb8b54448abd (patch)
treeb00174bb0f8f96dac875d797bd544e4bab0ace94 /drivers/rtc/rtc-ds1307.c
parent92cbf12fc200595611511fb3c5ab17d2627fa43c (diff)
downloadlinux-d0e3f61b08e222d3c6895085487cbb8b54448abd.tar.gz
rtc: ds1307: forward declare chips array instead of a bunch of functions
There used to be 16 declarations for static functions. By just adding a declaration for the chips array and reordering the functions the 16 function declarations can be dropped. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Diffstat (limited to 'drivers/rtc/rtc-ds1307.c')
-rw-r--r--drivers/rtc/rtc-ds1307.c622
1 files changed, 297 insertions, 325 deletions
diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c
index f7a47ee5cdf60..a4883d59d88de 100644
--- a/drivers/rtc/rtc-ds1307.c
+++ b/drivers/rtc/rtc-ds1307.c
@@ -184,289 +184,7 @@ struct chip_desc {
bool);
};
-static int ds1307_get_time(struct device *dev, struct rtc_time *t);
-static int ds1307_set_time(struct device *dev, struct rtc_time *t);
-static int ds1337_read_alarm(struct device *dev, struct rtc_wkalrm *t);
-static int ds1337_set_alarm(struct device *dev, struct rtc_wkalrm *t);
-static int ds1307_alarm_irq_enable(struct device *dev, unsigned int enabled);
-static u8 do_trickle_setup_ds1339(struct ds1307 *, u32 ohms, bool diode);
-static irqreturn_t rx8130_irq(int irq, void *dev_id);
-static int rx8130_read_alarm(struct device *dev, struct rtc_wkalrm *t);
-static int rx8130_set_alarm(struct device *dev, struct rtc_wkalrm *t);
-static int rx8130_alarm_irq_enable(struct device *dev, unsigned int enabled);
-static irqreturn_t mcp794xx_irq(int irq, void *dev_id);
-static int mcp794xx_read_alarm(struct device *dev, struct rtc_wkalrm *t);
-static int mcp794xx_set_alarm(struct device *dev, struct rtc_wkalrm *t);
-static int mcp794xx_alarm_irq_enable(struct device *dev, unsigned int enabled);
-static int m41txx_rtc_read_offset(struct device *dev, long *offset);
-static int m41txx_rtc_set_offset(struct device *dev, long offset);
-
-static const struct rtc_class_ops rx8130_rtc_ops = {
- .read_time = ds1307_get_time,
- .set_time = ds1307_set_time,
- .read_alarm = rx8130_read_alarm,
- .set_alarm = rx8130_set_alarm,
- .alarm_irq_enable = rx8130_alarm_irq_enable,
-};
-
-static const struct rtc_class_ops mcp794xx_rtc_ops = {
- .read_time = ds1307_get_time,
- .set_time = ds1307_set_time,
- .read_alarm = mcp794xx_read_alarm,
- .set_alarm = mcp794xx_set_alarm,
- .alarm_irq_enable = mcp794xx_alarm_irq_enable,
-};
-
-static const struct rtc_class_ops m41txx_rtc_ops = {
- .read_time = ds1307_get_time,
- .set_time = ds1307_set_time,
- .read_alarm = ds1337_read_alarm,
- .set_alarm = ds1337_set_alarm,
- .alarm_irq_enable = ds1307_alarm_irq_enable,
- .read_offset = m41txx_rtc_read_offset,
- .set_offset = m41txx_rtc_set_offset,
-};
-
-static const struct chip_desc chips[last_ds_type] = {
- [ds_1307] = {
- .nvram_offset = 8,
- .nvram_size = 56,
- },
- [ds_1308] = {
- .nvram_offset = 8,
- .nvram_size = 56,
- },
- [ds_1337] = {
- .alarm = 1,
- .century_reg = DS1307_REG_MONTH,
- .century_bit = DS1337_BIT_CENTURY,
- },
- [ds_1338] = {
- .nvram_offset = 8,
- .nvram_size = 56,
- },
- [ds_1339] = {
- .alarm = 1,
- .century_reg = DS1307_REG_MONTH,
- .century_bit = DS1337_BIT_CENTURY,
- .bbsqi_bit = DS1339_BIT_BBSQI,
- .trickle_charger_reg = 0x10,
- .do_trickle_setup = &do_trickle_setup_ds1339,
- },
- [ds_1340] = {
- .century_reg = DS1307_REG_HOUR,
- .century_enable_bit = DS1340_BIT_CENTURY_EN,
- .century_bit = DS1340_BIT_CENTURY,
- .do_trickle_setup = &do_trickle_setup_ds1339,
- .trickle_charger_reg = 0x08,
- },
- [ds_1341] = {
- .century_reg = DS1307_REG_MONTH,
- .century_bit = DS1337_BIT_CENTURY,
- },
- [ds_1388] = {
- .offset = 1,
- .trickle_charger_reg = 0x0a,
- },
- [ds_3231] = {
- .alarm = 1,
- .century_reg = DS1307_REG_MONTH,
- .century_bit = DS1337_BIT_CENTURY,
- .bbsqi_bit = DS3231_BIT_BBSQW,
- },
- [rx_8130] = {
- .alarm = 1,
- /* this is battery backed SRAM */
- .nvram_offset = 0x20,
- .nvram_size = 4, /* 32bit (4 word x 8 bit) */
- .offset = 0x10,
- .irq_handler = rx8130_irq,
- .rtc_ops = &rx8130_rtc_ops,
- },
- [m41t0] = {
- .rtc_ops = &m41txx_rtc_ops,
- },
- [m41t00] = {
- .rtc_ops = &m41txx_rtc_ops,
- },
- [m41t11] = {
- /* this is battery backed SRAM */
- .nvram_offset = 8,
- .nvram_size = 56,
- .rtc_ops = &m41txx_rtc_ops,
- },
- [mcp794xx] = {
- .alarm = 1,
- /* this is battery backed SRAM */
- .nvram_offset = 0x20,
- .nvram_size = 0x40,
- .irq_handler = mcp794xx_irq,
- .rtc_ops = &mcp794xx_rtc_ops,
- },
-};
-
-static const struct i2c_device_id ds1307_id[] = {
- { "ds1307", ds_1307 },
- { "ds1308", ds_1308 },
- { "ds1337", ds_1337 },
- { "ds1338", ds_1338 },
- { "ds1339", ds_1339 },
- { "ds1388", ds_1388 },
- { "ds1340", ds_1340 },
- { "ds1341", ds_1341 },
- { "ds3231", ds_3231 },
- { "m41t0", m41t0 },
- { "m41t00", m41t00 },
- { "m41t11", m41t11 },
- { "mcp7940x", mcp794xx },
- { "mcp7941x", mcp794xx },
- { "pt7c4338", ds_1307 },
- { "rx8025", rx_8025 },
- { "isl12057", ds_1337 },
- { "rx8130", rx_8130 },
- { }
-};
-MODULE_DEVICE_TABLE(i2c, ds1307_id);
-
-#ifdef CONFIG_OF
-static const struct of_device_id ds1307_of_match[] = {
- {
- .compatible = "dallas,ds1307",
- .data = (void *)ds_1307
- },
- {
- .compatible = "dallas,ds1308",
- .data = (void *)ds_1308
- },
- {
- .compatible = "dallas,ds1337",
- .data = (void *)ds_1337
- },
- {
- .compatible = "dallas,ds1338",
- .data = (void *)ds_1338
- },
- {
- .compatible = "dallas,ds1339",
- .data = (void *)ds_1339
- },
- {
- .compatible = "dallas,ds1388",
- .data = (void *)ds_1388
- },
- {
- .compatible = "dallas,ds1340",
- .data = (void *)ds_1340
- },
- {
- .compatible = "dallas,ds1341",
- .data = (void *)ds_1341
- },
- {
- .compatible = "maxim,ds3231",
- .data = (void *)ds_3231
- },
- {
- .compatible = "st,m41t0",
- .data = (void *)m41t0
- },
- {
- .compatible = "st,m41t00",
- .data = (void *)m41t00
- },
- {
- .compatible = "st,m41t11",
- .data = (void *)m41t11
- },
- {
- .compatible = "microchip,mcp7940x",
- .data = (void *)mcp794xx
- },
- {
- .compatible = "microchip,mcp7941x",
- .data = (void *)mcp794xx
- },
- {
- .compatible = "pericom,pt7c4338",
- .data = (void *)ds_1307
- },
- {
- .compatible = "epson,rx8025",
- .data = (void *)rx_8025
- },
- {
- .compatible = "isil,isl12057",
- .data = (void *)ds_1337
- },
- {
- .compatible = "epson,rx8130",
- .data = (void *)rx_8130
- },
- { }
-};
-MODULE_DEVICE_TABLE(of, ds1307_of_match);
-#endif
-
-#ifdef CONFIG_ACPI
-static const struct acpi_device_id ds1307_acpi_ids[] = {
- { .id = "DS1307", .driver_data = ds_1307 },
- { .id = "DS1308", .driver_data = ds_1308 },
- { .id = "DS1337", .driver_data = ds_1337 },
- { .id = "DS1338", .driver_data = ds_1338 },
- { .id = "DS1339", .driver_data = ds_1339 },
- { .id = "DS1388", .driver_data = ds_1388 },
- { .id = "DS1340", .driver_data = ds_1340 },
- { .id = "DS1341", .driver_data = ds_1341 },
- { .id = "DS3231", .driver_data = ds_3231 },
- { .id = "M41T0", .driver_data = m41t0 },
- { .id = "M41T00", .driver_data = m41t00 },
- { .id = "M41T11", .driver_data = m41t11 },
- { .id = "MCP7940X", .driver_data = mcp794xx },
- { .id = "MCP7941X", .driver_data = mcp794xx },
- { .id = "PT7C4338", .driver_data = ds_1307 },
- { .id = "RX8025", .driver_data = rx_8025 },
- { .id = "ISL12057", .driver_data = ds_1337 },
- { .id = "RX8130", .driver_data = rx_8130 },
- { }
-};
-MODULE_DEVICE_TABLE(acpi, ds1307_acpi_ids);
-#endif
-
-/*
- * The ds1337 and ds1339 both have two alarms, but we only use the first
- * one (with a "seconds" field). For ds1337 we expect nINTA is our alarm
- * signal; ds1339 chips have only one alarm signal.
- */
-static irqreturn_t ds1307_irq(int irq, void *dev_id)
-{
- struct ds1307 *ds1307 = dev_id;
- struct mutex *lock = &ds1307->rtc->ops_lock;
- int stat, ret;
-
- mutex_lock(lock);
- ret = regmap_read(ds1307->regmap, DS1337_REG_STATUS, &stat);
- if (ret)
- goto out;
-
- if (stat & DS1337_BIT_A1I) {
- stat &= ~DS1337_BIT_A1I;
- regmap_write(ds1307->regmap, DS1337_REG_STATUS, stat);
-
- ret = regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL,
- DS1337_BIT_A1IE, 0);
- if (ret)
- goto out;
-
- rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF);
- }
-
-out:
- mutex_unlock(lock);
-
- return IRQ_HANDLED;
-}
-
-/*----------------------------------------------------------------------*/
+static const struct chip_desc chips[last_ds_type];
static int ds1307_get_time(struct device *dev, struct rtc_time *t)
{
@@ -692,19 +410,28 @@ static int ds1307_alarm_irq_enable(struct device *dev, unsigned int enabled)
enabled ? DS1337_BIT_A1IE : 0);
}
-static const struct rtc_class_ops ds13xx_rtc_ops = {
- .read_time = ds1307_get_time,
- .set_time = ds1307_set_time,
- .read_alarm = ds1337_read_alarm,
- .set_alarm = ds1337_set_alarm,
- .alarm_irq_enable = ds1307_alarm_irq_enable,
-};
-
-/*----------------------------------------------------------------------*/
+static u8 do_trickle_setup_ds1339(struct ds1307 *ds1307, u32 ohms, bool diode)
+{
+ u8 setup = (diode) ? DS1307_TRICKLE_CHARGER_DIODE :
+ DS1307_TRICKLE_CHARGER_NO_DIODE;
-/*
- * Alarm support for rx8130 devices.
- */
+ switch (ohms) {
+ case 250:
+ setup |= DS1307_TRICKLE_CHARGER_250_OHM;
+ break;
+ case 2000:
+ setup |= DS1307_TRICKLE_CHARGER_2K_OHM;
+ break;
+ case 4000:
+ setup |= DS1307_TRICKLE_CHARGER_4K_OHM;
+ break;
+ default:
+ dev_warn(ds1307->dev,
+ "Unsupported ohm value %u in dt\n", ohms);
+ return 0;
+ }
+ return setup;
+}
static irqreturn_t rx8130_irq(int irq, void *dev_id)
{
@@ -849,12 +576,6 @@ static int rx8130_alarm_irq_enable(struct device *dev, unsigned int enabled)
return regmap_write(ds1307->regmap, RX8130_REG_CONTROL0, reg);
}
-/*----------------------------------------------------------------------*/
-
-/*
- * Alarm support for mcp794xx devices.
- */
-
static irqreturn_t mcp794xx_irq(int irq, void *dev_id)
{
struct ds1307 *ds1307 = dev_id;
@@ -1050,6 +771,281 @@ static int m41txx_rtc_set_offset(struct device *dev, long offset)
ctrl_reg);
}
+static const struct rtc_class_ops rx8130_rtc_ops = {
+ .read_time = ds1307_get_time,
+ .set_time = ds1307_set_time,
+ .read_alarm = rx8130_read_alarm,
+ .set_alarm = rx8130_set_alarm,
+ .alarm_irq_enable = rx8130_alarm_irq_enable,
+};
+
+static const struct rtc_class_ops mcp794xx_rtc_ops = {
+ .read_time = ds1307_get_time,
+ .set_time = ds1307_set_time,
+ .read_alarm = mcp794xx_read_alarm,
+ .set_alarm = mcp794xx_set_alarm,
+ .alarm_irq_enable = mcp794xx_alarm_irq_enable,
+};
+
+static const struct rtc_class_ops m41txx_rtc_ops = {
+ .read_time = ds1307_get_time,
+ .set_time = ds1307_set_time,
+ .read_alarm = ds1337_read_alarm,
+ .set_alarm = ds1337_set_alarm,
+ .alarm_irq_enable = ds1307_alarm_irq_enable,
+ .read_offset = m41txx_rtc_read_offset,
+ .set_offset = m41txx_rtc_set_offset,
+};
+
+static const struct chip_desc chips[last_ds_type] = {
+ [ds_1307] = {
+ .nvram_offset = 8,
+ .nvram_size = 56,
+ },
+ [ds_1308] = {
+ .nvram_offset = 8,
+ .nvram_size = 56,
+ },
+ [ds_1337] = {
+ .alarm = 1,
+ .century_reg = DS1307_REG_MONTH,
+ .century_bit = DS1337_BIT_CENTURY,
+ },
+ [ds_1338] = {
+ .nvram_offset = 8,
+ .nvram_size = 56,
+ },
+ [ds_1339] = {
+ .alarm = 1,
+ .century_reg = DS1307_REG_MONTH,
+ .century_bit = DS1337_BIT_CENTURY,
+ .bbsqi_bit = DS1339_BIT_BBSQI,
+ .trickle_charger_reg = 0x10,
+ .do_trickle_setup = &do_trickle_setup_ds1339,
+ },
+ [ds_1340] = {
+ .century_reg = DS1307_REG_HOUR,
+ .century_enable_bit = DS1340_BIT_CENTURY_EN,
+ .century_bit = DS1340_BIT_CENTURY,
+ .do_trickle_setup = &do_trickle_setup_ds1339,
+ .trickle_charger_reg = 0x08,
+ },
+ [ds_1341] = {
+ .century_reg = DS1307_REG_MONTH,
+ .century_bit = DS1337_BIT_CENTURY,
+ },
+ [ds_1388] = {
+ .offset = 1,
+ .trickle_charger_reg = 0x0a,
+ },
+ [ds_3231] = {
+ .alarm = 1,
+ .century_reg = DS1307_REG_MONTH,
+ .century_bit = DS1337_BIT_CENTURY,
+ .bbsqi_bit = DS3231_BIT_BBSQW,
+ },
+ [rx_8130] = {
+ .alarm = 1,
+ /* this is battery backed SRAM */
+ .nvram_offset = 0x20,
+ .nvram_size = 4, /* 32bit (4 word x 8 bit) */
+ .offset = 0x10,
+ .irq_handler = rx8130_irq,
+ .rtc_ops = &rx8130_rtc_ops,
+ },
+ [m41t0] = {
+ .rtc_ops = &m41txx_rtc_ops,
+ },
+ [m41t00] = {
+ .rtc_ops = &m41txx_rtc_ops,
+ },
+ [m41t11] = {
+ /* this is battery backed SRAM */
+ .nvram_offset = 8,
+ .nvram_size = 56,
+ .rtc_ops = &m41txx_rtc_ops,
+ },
+ [mcp794xx] = {
+ .alarm = 1,
+ /* this is battery backed SRAM */
+ .nvram_offset = 0x20,
+ .nvram_size = 0x40,
+ .irq_handler = mcp794xx_irq,
+ .rtc_ops = &mcp794xx_rtc_ops,
+ },
+};
+
+static const struct i2c_device_id ds1307_id[] = {
+ { "ds1307", ds_1307 },
+ { "ds1308", ds_1308 },
+ { "ds1337", ds_1337 },
+ { "ds1338", ds_1338 },
+ { "ds1339", ds_1339 },
+ { "ds1388", ds_1388 },
+ { "ds1340", ds_1340 },
+ { "ds1341", ds_1341 },
+ { "ds3231", ds_3231 },
+ { "m41t0", m41t0 },
+ { "m41t00", m41t00 },
+ { "m41t11", m41t11 },
+ { "mcp7940x", mcp794xx },
+ { "mcp7941x", mcp794xx },
+ { "pt7c4338", ds_1307 },
+ { "rx8025", rx_8025 },
+ { "isl12057", ds_1337 },
+ { "rx8130", rx_8130 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ds1307_id);
+
+#ifdef CONFIG_OF
+static const struct of_device_id ds1307_of_match[] = {
+ {
+ .compatible = "dallas,ds1307",
+ .data = (void *)ds_1307
+ },
+ {
+ .compatible = "dallas,ds1308",
+ .data = (void *)ds_1308
+ },
+ {
+ .compatible = "dallas,ds1337",
+ .data = (void *)ds_1337
+ },
+ {
+ .compatible = "dallas,ds1338",
+ .data = (void *)ds_1338
+ },
+ {
+ .compatible = "dallas,ds1339",
+ .data = (void *)ds_1339
+ },
+ {
+ .compatible = "dallas,ds1388",
+ .data = (void *)ds_1388
+ },
+ {
+ .compatible = "dallas,ds1340",
+ .data = (void *)ds_1340
+ },
+ {
+ .compatible = "dallas,ds1341",
+ .data = (void *)ds_1341
+ },
+ {
+ .compatible = "maxim,ds3231",
+ .data = (void *)ds_3231
+ },
+ {
+ .compatible = "st,m41t0",
+ .data = (void *)m41t0
+ },
+ {
+ .compatible = "st,m41t00",
+ .data = (void *)m41t00
+ },
+ {
+ .compatible = "st,m41t11",
+ .data = (void *)m41t11
+ },
+ {
+ .compatible = "microchip,mcp7940x",
+ .data = (void *)mcp794xx
+ },
+ {
+ .compatible = "microchip,mcp7941x",
+ .data = (void *)mcp794xx
+ },
+ {
+ .compatible = "pericom,pt7c4338",
+ .data = (void *)ds_1307
+ },
+ {
+ .compatible = "epson,rx8025",
+ .data = (void *)rx_8025
+ },
+ {
+ .compatible = "isil,isl12057",
+ .data = (void *)ds_1337
+ },
+ {
+ .compatible = "epson,rx8130",
+ .data = (void *)rx_8130
+ },
+ { }
+};
+MODULE_DEVICE_TABLE(of, ds1307_of_match);
+#endif
+
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id ds1307_acpi_ids[] = {
+ { .id = "DS1307", .driver_data = ds_1307 },
+ { .id = "DS1308", .driver_data = ds_1308 },
+ { .id = "DS1337", .driver_data = ds_1337 },
+ { .id = "DS1338", .driver_data = ds_1338 },
+ { .id = "DS1339", .driver_data = ds_1339 },
+ { .id = "DS1388", .driver_data = ds_1388 },
+ { .id = "DS1340", .driver_data = ds_1340 },
+ { .id = "DS1341", .driver_data = ds_1341 },
+ { .id = "DS3231", .driver_data = ds_3231 },
+ { .id = "M41T0", .driver_data = m41t0 },
+ { .id = "M41T00", .driver_data = m41t00 },
+ { .id = "M41T11", .driver_data = m41t11 },
+ { .id = "MCP7940X", .driver_data = mcp794xx },
+ { .id = "MCP7941X", .driver_data = mcp794xx },
+ { .id = "PT7C4338", .driver_data = ds_1307 },
+ { .id = "RX8025", .driver_data = rx_8025 },
+ { .id = "ISL12057", .driver_data = ds_1337 },
+ { .id = "RX8130", .driver_data = rx_8130 },
+ { }
+};
+MODULE_DEVICE_TABLE(acpi, ds1307_acpi_ids);
+#endif
+
+/*
+ * The ds1337 and ds1339 both have two alarms, but we only use the first
+ * one (with a "seconds" field). For ds1337 we expect nINTA is our alarm
+ * signal; ds1339 chips have only one alarm signal.
+ */
+static irqreturn_t ds1307_irq(int irq, void *dev_id)
+{
+ struct ds1307 *ds1307 = dev_id;
+ struct mutex *lock = &ds1307->rtc->ops_lock;
+ int stat, ret;
+
+ mutex_lock(lock);
+ ret = regmap_read(ds1307->regmap, DS1337_REG_STATUS, &stat);
+ if (ret)
+ goto out;
+
+ if (stat & DS1337_BIT_A1I) {
+ stat &= ~DS1337_BIT_A1I;
+ regmap_write(ds1307->regmap, DS1337_REG_STATUS, stat);
+
+ ret = regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL,
+ DS1337_BIT_A1IE, 0);
+ if (ret)
+ goto out;
+
+ rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF);
+ }
+
+out:
+ mutex_unlock(lock);
+
+ return IRQ_HANDLED;
+}
+
+/*----------------------------------------------------------------------*/
+
+static const struct rtc_class_ops ds13xx_rtc_ops = {
+ .read_time = ds1307_get_time,
+ .set_time = ds1307_set_time,
+ .read_alarm = ds1337_read_alarm,
+ .set_alarm = ds1337_set_alarm,
+ .alarm_irq_enable = ds1307_alarm_irq_enable,
+};
+
static ssize_t frequency_test_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
@@ -1137,30 +1133,6 @@ static int ds1307_nvram_write(void *priv, unsigned int offset, void *val,
/*----------------------------------------------------------------------*/
-static u8 do_trickle_setup_ds1339(struct ds1307 *ds1307,
- u32 ohms, bool diode)
-{
- u8 setup = (diode) ? DS1307_TRICKLE_CHARGER_DIODE :
- DS1307_TRICKLE_CHARGER_NO_DIODE;
-
- switch (ohms) {
- case 250:
- setup |= DS1307_TRICKLE_CHARGER_250_OHM;
- break;
- case 2000:
- setup |= DS1307_TRICKLE_CHARGER_2K_OHM;
- break;
- case 4000:
- setup |= DS1307_TRICKLE_CHARGER_4K_OHM;
- break;
- default:
- dev_warn(ds1307->dev,
- "Unsupported ohm value %u in dt\n", ohms);
- return 0;
- }
- return setup;
-}
-
static u8 ds1307_trickle_init(struct ds1307 *ds1307,
const struct chip_desc *chip)
{