// SPDX-License-Identifier: GPL-2.0 // Copyright (c) 2022 Nuvoton Technology Corporation #include #include #include #include #include #include #include #include #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 "); MODULE_AUTHOR("Mia Lin "); MODULE_DESCRIPTION("Nuvoton NCT3018Y RTC driver"); MODULE_LICENSE("GPL");