[PATCH 1/1] rtc: add AB-RTCMC-32.768kHz-EOZ9-S3 RTC support

From: Artem Panfilov
Date: Tue Jan 15 2019 - 06:02:30 EST

This patch adds support for AB-RTCMC-32.768kHz-EOZ9-S3
RTC/Calendar module w/ I2C interface.

Signed-off-by: Artem Panfilov <panfilov.artyom@xxxxxxxxx>
---
drivers/rtc/Kconfig | 10 +
drivers/rtc/Makefile | 1 +
drivers/rtc/rtc-ab-eoz9-s3.c | 412 +++++++++++++++++++++++++++++++++++
3 files changed, 423 insertions(+)
create mode 100644 drivers/rtc/rtc-ab-eoz9-s3.c

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 225b0b8516f3..a5536b206666 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -185,6 +185,16 @@ config RTC_DRV_ABB5ZES3
This driver can also be built as a module. If so, the module
will be called rtc-ab-b5ze-s3.

+config RTC_DRV_ABEOZ9S3
+ select REGMAP_I2C
+ tristate "Abracon AB-RTCMC-32.768kHz-EOZ9-S3"
+ help
+ If you say yes here you get support for the Abracon
+ AB-RTCMC-32.768kHz-EOA9-S3 I2C RTC chip.
+
+ This driver can also be built as a module. If so, the module
+ will be called rtc-ab-e0z9-s3.
+
config RTC_DRV_ABX80X
tristate "Abracon ABx80x"
select WATCHDOG_CORE if WATCHDOG
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index df022d820bee..b73e2307ace2 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -28,6 +28,7 @@ obj-$(CONFIG_RTC_DRV_88PM860X) += rtc-88pm860x.o
obj-$(CONFIG_RTC_DRV_AB3100) += rtc-ab3100.o
obj-$(CONFIG_RTC_DRV_AB8500) += rtc-ab8500.o
obj-$(CONFIG_RTC_DRV_ABB5ZES3) += rtc-ab-b5ze-s3.o
+obj-$(CONFIG_RTC_DRV_ABEOZ9S3) += rtc-ab-eoz9-s3.o
obj-$(CONFIG_RTC_DRV_ABX80X) += rtc-abx80x.o
obj-$(CONFIG_RTC_DRV_AC100) += rtc-ac100.o
obj-$(CONFIG_RTC_DRV_ARMADA38X) += rtc-armada38x.o
diff --git a/drivers/rtc/rtc-ab-eoz9-s3.c b/drivers/rtc/rtc-ab-eoz9-s3.c
new file mode 100644
index 000000000000..07a0fec7c80a
--- /dev/null
+++ b/drivers/rtc/rtc-ab-eoz9-s3.c
@@ -0,0 +1,412 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Real Time Clock driver for AB-RTCMC-32.768kHz-EOZ9-S3 chip.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/rtc.h>
+#include <linux/i2c.h>
+#include <linux/bcd.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+
+#define ABEOZ9S3_REG_CTRL1 0x00
+#define ABEOZ9S3_REG_CTRL1_MASK GENMASK(7, 0)
+#define ABEOZ9S3_REG_CTRL1_WE BIT(0)
+#define ABEOZ9S3_REG_CTRL1_TE BIT(1)
+#define ABEOZ9S3_REG_CTRL1_TAR BIT(2)
+#define ABEOZ9S3_REG_CTRL1_EERE BIT(3)
+#define ABEOZ9S3_REG_CTRL1_SRON BIT(4)
+#define ABEOZ9S3_REG_CTRL1_TD0 BIT(5)
+#define ABEOZ9S3_REG_CTRL1_TD1 BIT(6)
+#define ABEOZ9S3_REG_CTRL1_CLKINT BIT(7)
+
+#define ABEOZ9S3_REG_CTRL2 0x01
+#define ABEOZ9S3_REG_CTRL2_MASK GENMASK(4, 0)
+#define ABEOZ9S3_REG_CTRL2_AIE BIT(0)
+#define ABEOZ9S3_REG_CTRL2_TIE BIT(1)
+#define ABEOZ9S3_REG_CTRL2_V1IE BIT(2)
+#define ABEOZ9S3_REG_CTRL2_V2IE BIT(3)
+#define ABEOZ9S3_REG_CTRL2_SRIE BIT(4)
+
+#define ABEOZ9S3_REG_CTRL3 0x02
+#define ABEOZ9S3_REG_CTRL3_MASK GENMASK(4, 0)
+#define ABEOZ9S3_REG_CTRL3_AF BIT(0)
+#define ABEOZ9S3_REG_CTRL3_TF BIT(1)
+#define ABEOZ9S3_REG_CTRL3_V1IF BIT(2)
+#define ABEOZ9S3_REG_CTRL3_V2IF BIT(3)
+#define ABEOZ9S3_REG_CTRL3_SRF BIT(4)
+
+#define ABEOZ9S3_REG_CTRL4 0x03
+#define ABEOZ9S3_REG_CTRL4_MASK (BIT(7) | GENMASK(5, 0))
+#define ABEOZ9S3_REG_CTRL4_V1F BIT(2)
+#define ABEOZ9S3_REG_CTRL4_V2F BIT(3)
+#define ABEOZ9S3_REG_CTRL4_SR BIT(4)
+#define ABEOZ9S3_REG_CTRL4_PON BIT(5)
+#define ABEOZ9S3_REG_CTRL4_EEBUSY BIT(7)
+
+#define ABEOZ9S3_REG_SECONDS 0x08
+#define ABEOZ9S3_REG_MINUTES 0x09
+#define ABEOZ9S3_REG_HOURS 0x0A
+#define ABEOZ9S3_HOURS_PM BIT(6)
+#define ABEOZ9S3_REG_DAYS 0x0B
+#define ABEOZ9S3_REG_WEEKDAYS 0x0C
+#define ABEOZ9S3_REG_MONTHS 0x0D
+#define ABEOZ9S3_REG_YEARS 0x0E
+
+#define ABEOZ9S3_SECONDS_LEN 7
+
+#define ABEOZ9S3_REG_REG_TEMP 0x20
+#define ABEOZ953_TEMP_MAX 120
+#define ABEOZ953_TEMP_MIN -60
+
+#define ABEOZ9S3_REG_EEPROM 0x30
+#define ABEOZ9S3_REG_EEPROM_MASK GENMASK(8, 0)
+#define ABEOZ9S3_REG_EEPROM_THP BIT(0)
+#define ABEOZ9S3_REG_EEPROM_THE BIT(1)
+#define ABEOZ9S3_REG_EEPROM_FD0 BIT(2)
+#define ABEOZ9S3_REG_EEPROM_FD1 BIT(3)
+#define ABEOZ9S3_REG_EEPROM_R1K BIT(4)
+#define ABEOZ9S3_REG_EEPROM_R5K BIT(5)
+#define ABEOZ9S3_REG_EEPROM_R20K BIT(6)
+#define ABEOZ9S3_REG_EEPROM_R80K BIT(7)
+
+struct abeoz9s3_rtc_data {
+ struct rtc_device *rtc;
+ struct regmap *regmap;
+ struct mutex lock;
+ struct device *hwmon_dev;
+};
+
+static int abeoz9s3_rtc_get_time(struct device *dev, struct rtc_time *tm)
+{
+ struct abeoz9s3_rtc_data *data = dev_get_drvdata(dev);
+ u8 regs[ABEOZ9S3_REG_SECONDS + ABEOZ9S3_SECONDS_LEN];
+ int ret;
+
+ ret = regmap_bulk_read(data->regmap, ABEOZ9S3_REG_SECONDS,
+ regs, sizeof(regs));
+
+ if (ret) {
+ dev_err(dev, "reading RTC time failed (%d)\n", ret);
+ goto err;
+ }
+
+ tm->tm_sec = bcd2bin(regs[ABEOZ9S3_REG_SECONDS] & 0x7F);
+ tm->tm_min = bcd2bin(regs[ABEOZ9S3_REG_MINUTES] & 0x7F);
+
+ if (regs[ABEOZ9S3_REG_CTRL1] & ABEOZ9S3_HOURS_PM) {
+ tm->tm_hour = bcd2bin(regs[ABEOZ9S3_REG_HOURS] & 0x1f);
+ if (regs[ABEOZ9S3_REG_HOURS] & ABEOZ9S3_HOURS_PM)
+ tm->tm_hour += 12;
+ } else {
+ tm->tm_hour = bcd2bin(regs[ABEOZ9S3_REG_HOURS]);
+ }
+
+ tm->tm_mday = bcd2bin(regs[ABEOZ9S3_REG_DAYS]);
+ tm->tm_wday = bcd2bin(regs[ABEOZ9S3_REG_WEEKDAYS]);
+ tm->tm_mon = bcd2bin(regs[ABEOZ9S3_REG_MONTHS]) - 1;
+ tm->tm_year = bcd2bin(regs[ABEOZ9S3_REG_YEARS]) + 100;
+err:
+ return ret;
+}
+
+static int abeoz9s3_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct abeoz9s3_rtc_data *data = dev_get_drvdata(dev);
+ u8 regs[ABEOZ9S3_REG_SECONDS + ABEOZ9S3_SECONDS_LEN];
+ int ret;
+
+ regs[ABEOZ9S3_REG_SECONDS] = bin2bcd(tm->tm_sec);
+ regs[ABEOZ9S3_REG_MINUTES] = bin2bcd(tm->tm_min);
+ regs[ABEOZ9S3_REG_HOURS] = bin2bcd(tm->tm_hour);
+ regs[ABEOZ9S3_REG_DAYS] = bin2bcd(tm->tm_mday);
+ regs[ABEOZ9S3_REG_WEEKDAYS] = bin2bcd(tm->tm_wday);
+ regs[ABEOZ9S3_REG_MONTHS] = bin2bcd(tm->tm_mon + 1);
+ regs[ABEOZ9S3_REG_YEARS] = bin2bcd(tm->tm_year - 100);
+
+ mutex_lock(&data->lock);
+ ret = regmap_bulk_write(data->regmap, ABEOZ9S3_REG_SECONDS,
+ regs + ABEOZ9S3_REG_SECONDS,
+ ABEOZ9S3_SECONDS_LEN);
+ mutex_unlock(&data->lock);
+
+ return ret;
+}
+
+static int abeoz9s3_trickle_parse_dt(struct device_node *node)
+{
+ u32 ohms = 0;
+
+ if (of_property_read_u32(node, "trickle-resistor-ohms", &ohms))
+ return 0;
+
+ switch (ohms) {
+ case 1000:
+ return ABEOZ9S3_REG_EEPROM_R1K;
+ case 5000:
+ return ABEOZ9S3_REG_EEPROM_R5K;
+ case 20000:
+ return ABEOZ9S3_REG_EEPROM_R20K;
+ case 80000:
+ return ABEOZ9S3_REG_EEPROM_R80K;
+ default:
+ return 0;
+ }
+}
+
+static int abeoz9s3_rtc_setup(struct device *dev, struct device_node *node)
+{
+ struct abeoz9s3_rtc_data *data = dev_get_drvdata(dev);
+ struct regmap *regmap = data->regmap;
+
+ int ret;
+
+ /* Enable Self Recovery, Clock for Watch and EEPROM refresh functions*/
+ ret = regmap_update_bits(regmap, ABEOZ9S3_REG_CTRL1,
+ ABEOZ9S3_REG_CTRL1_MASK,
+ ABEOZ9S3_REG_CTRL1_WE |
+ ABEOZ9S3_REG_CTRL1_EERE |
+ ABEOZ9S3_REG_CTRL1_SRON);
+ if (ret < 0) {
+ dev_err(dev, "unable to set control 1 register (%d)\n", ret);
+ return ret;
+ }
+
+ ret = regmap_update_bits(regmap, ABEOZ9S3_REG_CTRL2,
+ ABEOZ9S3_REG_CTRL2_MASK, 0);
+ if (ret < 0) {
+ dev_err(dev, "unable to set control 2 register (%d)\n", ret);
+ return ret;
+ }
+
+ ret = regmap_update_bits(regmap, ABEOZ9S3_REG_CTRL3,
+ ABEOZ9S3_REG_CTRL3_MASK, 0);
+ if (ret < 0) {
+ dev_err(dev, "unable to set control 3 register (%d)\n", ret);
+ return ret;
+ }
+
+ ret = regmap_update_bits(regmap, ABEOZ9S3_REG_CTRL4,
+ ABEOZ9S3_REG_CTRL4_MASK, 0);
+ if (ret < 0) {
+ dev_err(dev, "unable to set control 4 register (%d)\n", ret);
+ return ret;
+ }
+
+ ret = abeoz9s3_trickle_parse_dt(node);
+
+ /* Enable built-in termometer */
+ ret |= ABEOZ9S3_REG_EEPROM_THE;
+
+ ret = regmap_update_bits(regmap, ABEOZ9S3_REG_EEPROM,
+ ABEOZ9S3_REG_EEPROM_MASK,
+ ret);
+ if (ret < 0) {
+ dev_err(dev, "unable to set eeprom register (%d)\n", ret);
+ return ret;
+ }
+
+ return ret;
+}
+
+static const struct rtc_class_ops rtc_ops = {
+ .read_time = abeoz9s3_rtc_get_time,
+ .set_time = abeoz9s3_rtc_set_time,
+};
+
+static const struct regmap_config abeoz9s3_rtc_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+};
+
+#if IS_REACHABLE(CONFIG_HWMON)
+
+static int abeoz9z3_temp_read(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long *temp)
+{
+ struct abeoz9s3_rtc_data *data = dev_get_drvdata(dev);
+ struct regmap *regmap = data->regmap;
+ int ret;
+ unsigned int regval = 37;
+
+ switch (attr) {
+ case hwmon_temp_input:
+ ret = regmap_read(regmap, ABEOZ9S3_REG_REG_TEMP, &regval);
+ if (ret < 0)
+ return ret;
+ *temp = 1000 * (regval + ABEOZ953_TEMP_MIN);
+ return 0;
+ case hwmon_temp_max:
+ *temp = 1000 * ABEOZ953_TEMP_MAX;
+ return 0;
+ case hwmon_temp_min:
+ *temp = 1000 * ABEOZ953_TEMP_MIN;
+ return 0;
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static umode_t abeoz9s3_is_visible(const void *data,
+ enum hwmon_sensor_types type,
+ u32 attr, int channel)
+{
+ switch (attr) {
+ case hwmon_temp_input:
+ case hwmon_temp_max:
+ case hwmon_temp_min:
+ return 0444;
+ default:
+ return 0;
+ }
+}
+
+static const u32 abeoz9s3_chip_config[] = {
+ HWMON_C_REGISTER_TZ,
+ 0
+};
+
+static const struct hwmon_channel_info abeoz9s3_chip = {
+ .type = hwmon_chip,
+ .config = abeoz9s3_chip_config,
+};
+
+static const u32 abeoz9s3_temp_config[] = {
+ HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN,
+ 0
+};
+
+static const struct hwmon_channel_info abeoz9s3_temp = {
+ .type = hwmon_temp,
+ .config = abeoz9s3_temp_config,
+};
+
+static const struct hwmon_channel_info *abeoz9s3_info[] = {
+ &abeoz9s3_chip,
+ &abeoz9s3_temp,
+ NULL
+};
+
+static const struct hwmon_ops abeoz9s3_hwmon_ops = {
+ .is_visible = abeoz9s3_is_visible,
+ .read = abeoz9z3_temp_read,
+};
+
+static const struct hwmon_chip_info abeoz9s3_chip_info = {
+ .ops = &abeoz9s3_hwmon_ops,
+ .info = abeoz9s3_info,
+};
+
+static void abeoz9s3_hwmon_register(struct device *dev,
+ struct abeoz9s3_rtc_data *data)
+{
+ data->hwmon_dev =
+ devm_hwmon_device_register_with_info(dev,
+ "abeoz9s3",
+ data,
+ &abeoz9s3_chip_info,
+ NULL);
+ if (IS_ERR(data->hwmon_dev)) {
+ dev_warn(dev, "unable to register hwmon device %ld\n",
+ PTR_ERR(data->hwmon_dev));
+ }
+}
+
+#else
+
+static void abeoz9s3_hwmon_register(struct device *dev,
+ struct abeoz9s3_rtc_data *data)
+{
+}
+
+#endif /* CONFIG_RTC_DRV_ABEOZ9S3_HWMON */
+
+static int abeoz9s3_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct abeoz9s3_rtc_data *data = NULL;
+ struct device *dev = &client->dev;
+ struct regmap *regmap;
+ int ret;
+
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C |
+ I2C_FUNC_SMBUS_BYTE_DATA |
+ I2C_FUNC_SMBUS_I2C_BLOCK)) {
+ ret = -ENODEV;
+ goto err;
+ }
+
+ regmap = devm_regmap_init_i2c(client, &abeoz9s3_rtc_regmap_config);
+ if (IS_ERR(regmap)) {
+ ret = PTR_ERR(regmap);
+ dev_err(dev, "regmap allocation failed: %d\n", ret);
+ goto err;
+ }
+
+ data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+ if (!data) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ mutex_init(&data->lock);
+ data->regmap = regmap;
+ dev_set_drvdata(dev, data);
+
+ ret = abeoz9s3_rtc_setup(dev, client->dev.of_node);
+ if (ret)
+ goto err;
+
+ data->rtc = devm_rtc_allocate_device(dev);
+ ret = PTR_ERR_OR_ZERO(data->rtc);
+ if (ret)
+ goto err;
+
+ data->rtc->ops = &rtc_ops;
+ data->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
+ data->rtc->range_max = RTC_TIMESTAMP_END_2099;
+
+ ret = rtc_register_device(data->rtc);
+ if (ret)
+ goto err;
+
+ abeoz9s3_hwmon_register(dev, data);
+ return 0;
+err:
+ dev_err(dev, "unable to register RTC device (%d)\n", ret);
+ return ret;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id abeoz9s3_dt_match[] = {
+ { .compatible = "abracon,abeoz9s3" },
+ { },
+};
+#endif
+
+MODULE_DEVICE_TABLE(of, abeoz9s3_dt_match);
+
+static const struct i2c_device_id abeoz9s3_id[] = {
+ { "abeoz9s3", 0 },
+ { }
+};
+
+static struct i2c_driver abeoz9s3_driver = {
+ .driver = {
+ .name = "rtc-ab-eoz9-s3",
+ .of_match_table = of_match_ptr(abeoz9s3_dt_match),
+ },
+ .probe = abeoz9s3_probe,
+ .id_table = abeoz9s3_id,
+};
+
+module_i2c_driver(abeoz9s3_driver);
+
+MODULE_AUTHOR("Artem Panfilov panfilov.artyom@xxxxxxxxx");
+MODULE_DESCRIPTION("Abracon AB-RTCMC-32.768kHz-EOZ9-S3 RTC driver");
+MODULE_LICENSE("GPL");
--
2.17.1