| // SPDX-License-Identifier: GPL-2.0 |
| // Copyright (c) 2022 Nuvoton Technology Corporation |
| |
| #include <linux/bcd.h> |
| #include <linux/clk-provider.h> |
| #include <linux/err.h> |
| #include <linux/i2c.h> |
| #include <linux/module.h> |
| #include <linux/of.h> |
| #include <linux/rtc.h> |
| #include <linux/slab.h> |
| |
| #define NCT3018Y_REG_SC 0x00 /* seconds */ |
| #define NCT3018Y_REG_SCA 0x01 /* alarm */ |
| #define NCT3018Y_REG_MN 0x02 |
| #define NCT3018Y_REG_MNA 0x03 /* alarm */ |
| #define NCT3018Y_REG_HR 0x04 |
| #define NCT3018Y_REG_HRA 0x05 /* alarm */ |
| #define NCT3018Y_REG_DW 0x06 |
| #define NCT3018Y_REG_DM 0x07 |
| #define NCT3018Y_REG_MO 0x08 |
| #define NCT3018Y_REG_YR 0x09 |
| #define NCT3018Y_REG_CTRL 0x0A /* timer control */ |
| #define NCT3018Y_REG_ST 0x0B /* status */ |
| #define NCT3018Y_REG_CLKO 0x0C /* clock out */ |
| #define NCT3018Y_REG_PART 0x21 /* part info */ |
| |
| #define NCT3018Y_BIT_AF BIT(7) |
| #define NCT3018Y_BIT_ST BIT(7) |
| #define NCT3018Y_BIT_DM BIT(6) |
| #define NCT3018Y_BIT_HF BIT(5) |
| #define NCT3018Y_BIT_DSM BIT(4) |
| #define NCT3018Y_BIT_AIE BIT(3) |
| #define NCT3018Y_BIT_OFIE BIT(2) |
| #define NCT3018Y_BIT_CIE BIT(1) |
| #define NCT3018Y_BIT_TWO BIT(0) |
| |
| #define NCT3018Y_REG_BAT_MASK 0x07 |
| #define NCT3018Y_REG_CLKO_F_MASK 0x03 /* frequenc mask */ |
| #define NCT3018Y_REG_CLKO_CKE 0x80 /* clock out enabled */ |
| #define NCT3018Y_REG_PART_NCT3018Y 0x02 |
| |
| struct nct3018y { |
| struct rtc_device *rtc; |
| struct i2c_client *client; |
| int part_num; |
| #ifdef CONFIG_COMMON_CLK |
| struct clk_hw clkout_hw; |
| #endif |
| }; |
| |
| static int nct3018y_set_alarm_mode(struct i2c_client *client, bool on) |
| { |
| int err, flags; |
| |
| dev_dbg(&client->dev, "%s:on:%d\n", __func__, on); |
| |
| flags = i2c_smbus_read_byte_data(client, NCT3018Y_REG_CTRL); |
| if (flags < 0) { |
| dev_dbg(&client->dev, |
| "Failed to read NCT3018Y_REG_CTRL\n"); |
| return flags; |
| } |
| |
| if (on) |
| flags |= NCT3018Y_BIT_AIE; |
| else |
| flags &= ~NCT3018Y_BIT_AIE; |
| |
| flags |= NCT3018Y_BIT_CIE; |
| err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_CTRL, flags); |
| if (err < 0) { |
| dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_CTRL\n"); |
| return err; |
| } |
| |
| flags = i2c_smbus_read_byte_data(client, NCT3018Y_REG_ST); |
| if (flags < 0) { |
| dev_dbg(&client->dev, |
| "Failed to read NCT3018Y_REG_ST\n"); |
| return flags; |
| } |
| |
| flags &= ~(NCT3018Y_BIT_AF); |
| err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_ST, flags); |
| if (err < 0) { |
| dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_ST\n"); |
| return err; |
| } |
| |
| return 0; |
| } |
| |
| static int nct3018y_get_alarm_mode(struct i2c_client *client, unsigned char *alarm_enable, |
| unsigned char *alarm_flag) |
| { |
| int flags; |
| |
| if (alarm_enable) { |
| dev_dbg(&client->dev, "%s:NCT3018Y_REG_CTRL\n", __func__); |
| flags = i2c_smbus_read_byte_data(client, NCT3018Y_REG_CTRL); |
| if (flags < 0) |
| return flags; |
| *alarm_enable = flags & NCT3018Y_BIT_AIE; |
| dev_dbg(&client->dev, "%s:alarm_enable:%x\n", __func__, *alarm_enable); |
| |
| } |
| |
| if (alarm_flag) { |
| dev_dbg(&client->dev, "%s:NCT3018Y_REG_ST\n", __func__); |
| flags = i2c_smbus_read_byte_data(client, NCT3018Y_REG_ST); |
| if (flags < 0) |
| return flags; |
| *alarm_flag = flags & NCT3018Y_BIT_AF; |
| dev_dbg(&client->dev, "%s:alarm_flag:%x\n", __func__, *alarm_flag); |
| } |
| |
| return 0; |
| } |
| |
| static irqreturn_t nct3018y_irq(int irq, void *dev_id) |
| { |
| struct nct3018y *nct3018y = i2c_get_clientdata(dev_id); |
| struct i2c_client *client = nct3018y->client; |
| int err; |
| unsigned char alarm_flag; |
| unsigned char alarm_enable; |
| |
| dev_dbg(&client->dev, "%s:irq:%d\n", __func__, irq); |
| err = nct3018y_get_alarm_mode(nct3018y->client, &alarm_enable, &alarm_flag); |
| if (err) |
| return IRQ_NONE; |
| |
| if (alarm_flag) { |
| dev_dbg(&client->dev, "%s:alarm flag:%x\n", |
| __func__, alarm_flag); |
| rtc_update_irq(nct3018y->rtc, 1, RTC_IRQF | RTC_AF); |
| nct3018y_set_alarm_mode(nct3018y->client, 0); |
| dev_dbg(&client->dev, "%s:IRQ_HANDLED\n", __func__); |
| return IRQ_HANDLED; |
| } |
| |
| return IRQ_NONE; |
| } |
| |
| /* |
| * In the routines that deal directly with the nct3018y hardware, we use |
| * rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch. |
| */ |
| static int nct3018y_rtc_read_time(struct device *dev, struct rtc_time *tm) |
| { |
| struct i2c_client *client = to_i2c_client(dev); |
| unsigned char buf[10]; |
| int err; |
| |
| err = i2c_smbus_read_i2c_block_data(client, NCT3018Y_REG_ST, 1, buf); |
| if (err < 0) |
| return err; |
| |
| if (!buf[0]) { |
| dev_dbg(&client->dev, " voltage <=1.7, date/time is not reliable.\n"); |
| return -EINVAL; |
| } |
| |
| err = i2c_smbus_read_i2c_block_data(client, NCT3018Y_REG_SC, sizeof(buf), buf); |
| if (err < 0) |
| return err; |
| |
| tm->tm_sec = bcd2bin(buf[0] & 0x7F); |
| tm->tm_min = bcd2bin(buf[2] & 0x7F); |
| tm->tm_hour = bcd2bin(buf[4] & 0x3F); |
| tm->tm_wday = buf[6] & 0x07; |
| tm->tm_mday = bcd2bin(buf[7] & 0x3F); |
| tm->tm_mon = bcd2bin(buf[8] & 0x1F) - 1; |
| tm->tm_year = bcd2bin(buf[9]) + 100; |
| |
| return 0; |
| } |
| |
| static int nct3018y_rtc_set_time(struct device *dev, struct rtc_time *tm) |
| { |
| struct i2c_client *client = to_i2c_client(dev); |
| struct nct3018y *nct3018y = dev_get_drvdata(dev); |
| unsigned char buf[4] = {0}; |
| int err, flags; |
| int restore_flags = 0; |
| |
| flags = i2c_smbus_read_byte_data(client, NCT3018Y_REG_CTRL); |
| if (flags < 0) { |
| dev_dbg(&client->dev, "Failed to read NCT3018Y_REG_CTRL.\n"); |
| return flags; |
| } |
| |
| /* Check and set TWO bit */ |
| if (nct3018y->part_num == NCT3018Y_REG_PART_NCT3018Y && !(flags & NCT3018Y_BIT_TWO)) { |
| restore_flags = 1; |
| flags |= NCT3018Y_BIT_TWO; |
| err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_CTRL, flags); |
| if (err < 0) { |
| dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_CTRL.\n"); |
| return err; |
| } |
| } |
| |
| buf[0] = bin2bcd(tm->tm_sec); |
| err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_SC, buf[0]); |
| if (err < 0) { |
| dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_SC\n"); |
| return err; |
| } |
| |
| buf[0] = bin2bcd(tm->tm_min); |
| err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_MN, buf[0]); |
| if (err < 0) { |
| dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_MN\n"); |
| return err; |
| } |
| |
| buf[0] = bin2bcd(tm->tm_hour); |
| err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_HR, buf[0]); |
| if (err < 0) { |
| dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_HR\n"); |
| return err; |
| } |
| |
| buf[0] = tm->tm_wday & 0x07; |
| buf[1] = bin2bcd(tm->tm_mday); |
| buf[2] = bin2bcd(tm->tm_mon + 1); |
| buf[3] = bin2bcd(tm->tm_year - 100); |
| err = i2c_smbus_write_i2c_block_data(client, NCT3018Y_REG_DW, |
| sizeof(buf), buf); |
| if (err < 0) { |
| dev_dbg(&client->dev, "Unable to write for day and mon and year\n"); |
| return -EIO; |
| } |
| |
| /* Restore TWO bit */ |
| if (restore_flags) { |
| if (nct3018y->part_num == NCT3018Y_REG_PART_NCT3018Y) |
| flags &= ~NCT3018Y_BIT_TWO; |
| |
| err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_CTRL, flags); |
| if (err < 0) { |
| dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_CTRL.\n"); |
| return err; |
| } |
| } |
| |
| return err; |
| } |
| |
| static int nct3018y_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *tm) |
| { |
| struct i2c_client *client = to_i2c_client(dev); |
| unsigned char buf[5]; |
| int err; |
| |
| err = i2c_smbus_read_i2c_block_data(client, NCT3018Y_REG_SCA, |
| sizeof(buf), buf); |
| if (err < 0) { |
| dev_dbg(&client->dev, "Unable to read date\n"); |
| return -EIO; |
| } |
| |
| dev_dbg(&client->dev, "%s: raw data is sec=%02x, min=%02x hr=%02x\n", |
| __func__, buf[0], buf[2], buf[4]); |
| |
| tm->time.tm_sec = bcd2bin(buf[0] & 0x7F); |
| tm->time.tm_min = bcd2bin(buf[2] & 0x7F); |
| tm->time.tm_hour = bcd2bin(buf[4] & 0x3F); |
| |
| err = nct3018y_get_alarm_mode(client, &tm->enabled, &tm->pending); |
| if (err < 0) |
| return err; |
| |
| dev_dbg(&client->dev, "%s:s=%d m=%d, hr=%d, enabled=%d, pending=%d\n", |
| __func__, tm->time.tm_sec, tm->time.tm_min, |
| tm->time.tm_hour, tm->enabled, tm->pending); |
| |
| return 0; |
| } |
| |
| static int nct3018y_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *tm) |
| { |
| struct i2c_client *client = to_i2c_client(dev); |
| int err; |
| |
| dev_dbg(dev, "%s, sec=%d, min=%d hour=%d tm->enabled:%d\n", |
| __func__, tm->time.tm_sec, tm->time.tm_min, tm->time.tm_hour, |
| tm->enabled); |
| |
| err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_SCA, bin2bcd(tm->time.tm_sec)); |
| if (err < 0) { |
| dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_SCA\n"); |
| return err; |
| } |
| |
| err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_MNA, bin2bcd(tm->time.tm_min)); |
| if (err < 0) { |
| dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_MNA\n"); |
| return err; |
| } |
| |
| err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_HRA, bin2bcd(tm->time.tm_hour)); |
| if (err < 0) { |
| dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_HRA\n"); |
| return err; |
| } |
| |
| return nct3018y_set_alarm_mode(client, tm->enabled); |
| } |
| |
| static int nct3018y_irq_enable(struct device *dev, unsigned int enabled) |
| { |
| dev_dbg(dev, "%s: alarm enable=%d\n", __func__, enabled); |
| |
| return nct3018y_set_alarm_mode(to_i2c_client(dev), enabled); |
| } |
| |
| static int nct3018y_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) |
| { |
| struct i2c_client *client = to_i2c_client(dev); |
| int status, flags = 0; |
| |
| switch (cmd) { |
| case RTC_VL_READ: |
| status = i2c_smbus_read_byte_data(client, NCT3018Y_REG_ST); |
| if (status < 0) |
| return status; |
| |
| if (!(status & NCT3018Y_REG_BAT_MASK)) |
| flags |= RTC_VL_DATA_INVALID; |
| |
| return put_user(flags, (unsigned int __user *)arg); |
| |
| default: |
| return -ENOIOCTLCMD; |
| } |
| } |
| |
| #ifdef CONFIG_COMMON_CLK |
| /* |
| * Handling of the clkout |
| */ |
| |
| #define clkout_hw_to_nct3018y(_hw) container_of(_hw, struct nct3018y, clkout_hw) |
| |
| static const int clkout_rates[] = { |
| 32768, |
| 1024, |
| 32, |
| 1, |
| }; |
| |
| static unsigned long nct3018y_clkout_recalc_rate(struct clk_hw *hw, |
| unsigned long parent_rate) |
| { |
| struct nct3018y *nct3018y = clkout_hw_to_nct3018y(hw); |
| struct i2c_client *client = nct3018y->client; |
| int flags; |
| |
| flags = i2c_smbus_read_byte_data(client, NCT3018Y_REG_CLKO); |
| if (flags < 0) |
| return 0; |
| |
| flags &= NCT3018Y_REG_CLKO_F_MASK; |
| return clkout_rates[flags]; |
| } |
| |
| static long nct3018y_clkout_round_rate(struct clk_hw *hw, unsigned long rate, |
| unsigned long *prate) |
| { |
| int i; |
| |
| for (i = 0; i < ARRAY_SIZE(clkout_rates); i++) |
| if (clkout_rates[i] <= rate) |
| return clkout_rates[i]; |
| |
| return 0; |
| } |
| |
| static int nct3018y_clkout_set_rate(struct clk_hw *hw, unsigned long rate, |
| unsigned long parent_rate) |
| { |
| struct nct3018y *nct3018y = clkout_hw_to_nct3018y(hw); |
| struct i2c_client *client = nct3018y->client; |
| int i, flags; |
| |
| flags = i2c_smbus_read_byte_data(client, NCT3018Y_REG_CLKO); |
| if (flags < 0) |
| return flags; |
| |
| for (i = 0; i < ARRAY_SIZE(clkout_rates); i++) |
| if (clkout_rates[i] == rate) { |
| flags &= ~NCT3018Y_REG_CLKO_F_MASK; |
| flags |= i; |
| return i2c_smbus_write_byte_data(client, NCT3018Y_REG_CLKO, flags); |
| } |
| |
| return -EINVAL; |
| } |
| |
| static int nct3018y_clkout_control(struct clk_hw *hw, bool enable) |
| { |
| struct nct3018y *nct3018y = clkout_hw_to_nct3018y(hw); |
| struct i2c_client *client = nct3018y->client; |
| int flags; |
| |
| flags = i2c_smbus_read_byte_data(client, NCT3018Y_REG_CLKO); |
| if (flags < 0) |
| return flags; |
| |
| if (enable) |
| flags |= NCT3018Y_REG_CLKO_CKE; |
| else |
| flags &= ~NCT3018Y_REG_CLKO_CKE; |
| |
| return i2c_smbus_write_byte_data(client, NCT3018Y_REG_CLKO, flags); |
| } |
| |
| static int nct3018y_clkout_prepare(struct clk_hw *hw) |
| { |
| return nct3018y_clkout_control(hw, 1); |
| } |
| |
| static void nct3018y_clkout_unprepare(struct clk_hw *hw) |
| { |
| nct3018y_clkout_control(hw, 0); |
| } |
| |
| static int nct3018y_clkout_is_prepared(struct clk_hw *hw) |
| { |
| struct nct3018y *nct3018y = clkout_hw_to_nct3018y(hw); |
| struct i2c_client *client = nct3018y->client; |
| int flags; |
| |
| flags = i2c_smbus_read_byte_data(client, NCT3018Y_REG_CLKO); |
| if (flags < 0) |
| return flags; |
| |
| return flags & NCT3018Y_REG_CLKO_CKE; |
| } |
| |
| static const struct clk_ops nct3018y_clkout_ops = { |
| .prepare = nct3018y_clkout_prepare, |
| .unprepare = nct3018y_clkout_unprepare, |
| .is_prepared = nct3018y_clkout_is_prepared, |
| .recalc_rate = nct3018y_clkout_recalc_rate, |
| .round_rate = nct3018y_clkout_round_rate, |
| .set_rate = nct3018y_clkout_set_rate, |
| }; |
| |
| static struct clk *nct3018y_clkout_register_clk(struct nct3018y *nct3018y) |
| { |
| struct i2c_client *client = nct3018y->client; |
| struct device_node *node = client->dev.of_node; |
| struct clk *clk; |
| struct clk_init_data init; |
| |
| init.name = "nct3018y-clkout"; |
| init.ops = &nct3018y_clkout_ops; |
| init.flags = 0; |
| init.parent_names = NULL; |
| init.num_parents = 0; |
| nct3018y->clkout_hw.init = &init; |
| |
| /* optional override of the clockname */ |
| of_property_read_string(node, "clock-output-names", &init.name); |
| |
| /* register the clock */ |
| clk = devm_clk_register(&client->dev, &nct3018y->clkout_hw); |
| |
| if (!IS_ERR(clk)) |
| of_clk_add_provider(node, of_clk_src_simple_get, clk); |
| |
| return clk; |
| } |
| #endif |
| |
| static const struct rtc_class_ops nct3018y_rtc_ops = { |
| .read_time = nct3018y_rtc_read_time, |
| .set_time = nct3018y_rtc_set_time, |
| .read_alarm = nct3018y_rtc_read_alarm, |
| .set_alarm = nct3018y_rtc_set_alarm, |
| .alarm_irq_enable = nct3018y_irq_enable, |
| .ioctl = nct3018y_ioctl, |
| }; |
| |
| static int nct3018y_probe(struct i2c_client *client) |
| { |
| struct nct3018y *nct3018y; |
| int err, flags; |
| |
| if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C | |
| I2C_FUNC_SMBUS_BYTE | |
| I2C_FUNC_SMBUS_BLOCK_DATA)) |
| return -ENODEV; |
| |
| nct3018y = devm_kzalloc(&client->dev, sizeof(struct nct3018y), |
| GFP_KERNEL); |
| if (!nct3018y) |
| return -ENOMEM; |
| |
| i2c_set_clientdata(client, nct3018y); |
| nct3018y->client = client; |
| device_set_wakeup_capable(&client->dev, 1); |
| |
| flags = i2c_smbus_read_byte_data(client, NCT3018Y_REG_CTRL); |
| if (flags < 0) { |
| dev_dbg(&client->dev, "%s: read error\n", __func__); |
| return flags; |
| } else if (flags & NCT3018Y_BIT_TWO) { |
| dev_dbg(&client->dev, "%s: NCT3018Y_BIT_TWO is set\n", __func__); |
| } |
| |
| nct3018y->part_num = i2c_smbus_read_byte_data(client, NCT3018Y_REG_PART); |
| if (nct3018y->part_num < 0) { |
| dev_dbg(&client->dev, "Failed to read NCT3018Y_REG_PART.\n"); |
| return nct3018y->part_num; |
| } else if (nct3018y->part_num == NCT3018Y_REG_PART_NCT3018Y) { |
| flags = NCT3018Y_BIT_HF; |
| err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_CTRL, flags); |
| if (err < 0) { |
| dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_CTRL.\n"); |
| return err; |
| } |
| } |
| |
| flags = 0; |
| err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_ST, flags); |
| if (err < 0) { |
| dev_dbg(&client->dev, "%s: write error\n", __func__); |
| return err; |
| } |
| |
| nct3018y->rtc = devm_rtc_allocate_device(&client->dev); |
| if (IS_ERR(nct3018y->rtc)) |
| return PTR_ERR(nct3018y->rtc); |
| |
| nct3018y->rtc->ops = &nct3018y_rtc_ops; |
| nct3018y->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000; |
| nct3018y->rtc->range_max = RTC_TIMESTAMP_END_2099; |
| |
| if (client->irq > 0) { |
| err = devm_request_threaded_irq(&client->dev, client->irq, |
| NULL, nct3018y_irq, |
| IRQF_ONESHOT | IRQF_TRIGGER_FALLING, |
| "nct3018y", client); |
| if (err) { |
| dev_dbg(&client->dev, "unable to request IRQ %d\n", client->irq); |
| return err; |
| } |
| } else { |
| clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, nct3018y->rtc->features); |
| clear_bit(RTC_FEATURE_ALARM, nct3018y->rtc->features); |
| } |
| |
| #ifdef CONFIG_COMMON_CLK |
| /* register clk in common clk framework */ |
| nct3018y_clkout_register_clk(nct3018y); |
| #endif |
| |
| return devm_rtc_register_device(nct3018y->rtc); |
| } |
| |
| static const struct i2c_device_id nct3018y_id[] = { |
| { "nct3018y", 0 }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(i2c, nct3018y_id); |
| |
| static const struct of_device_id nct3018y_of_match[] = { |
| { .compatible = "nuvoton,nct3018y" }, |
| {} |
| }; |
| MODULE_DEVICE_TABLE(of, nct3018y_of_match); |
| |
| static struct i2c_driver nct3018y_driver = { |
| .driver = { |
| .name = "rtc-nct3018y", |
| .of_match_table = nct3018y_of_match, |
| }, |
| .probe = nct3018y_probe, |
| .id_table = nct3018y_id, |
| }; |
| |
| module_i2c_driver(nct3018y_driver); |
| |
| MODULE_AUTHOR("Medad CChien <ctcchien@nuvoton.com>"); |
| MODULE_AUTHOR("Mia Lin <mimi05633@gmail.com>"); |
| MODULE_DESCRIPTION("Nuvoton NCT3018Y RTC driver"); |
| MODULE_LICENSE("GPL"); |