Add real time clock support for NCT3018Y. Signed-off-by: Medad CChien <ctcchien@xxxxxxxxxxx> --- drivers/rtc/Kconfig | 10 + drivers/rtc/Makefile | 1 + drivers/rtc/rtc-nct3018y.c | 599 +++++++++++++++++++++++++++++++++++++ 3 files changed, 610 insertions(+) create mode 100644 drivers/rtc/rtc-nct3018y.c diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index d85a3c31347c..d83d31c76443 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -383,6 +383,16 @@ config RTC_DRV_MAX77686 This driver can also be built as a module. If so, the module will be called rtc-max77686. +config RTC_DRV_NCT3018Y + tristate "Nuvoton Real Time Clock" + depends on OF + help + If you say yes here you get support for the Nuvoton NCT3018Y RTC + module. + + This driver can also be built as a module, if so, the module will + be called "rtc-nct3018y". + config RTC_DRV_RK808 tristate "Rockchip RK805/RK808/RK809/RK817/RK818 RTC" depends on MFD_RK808 diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index e92f3e943245..d3c100e43d1f 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -112,6 +112,7 @@ obj-$(CONFIG_RTC_DRV_MV) += rtc-mv.o obj-$(CONFIG_RTC_DRV_MXC) += rtc-mxc.o obj-$(CONFIG_RTC_DRV_MXC_V2) += rtc-mxc_v2.o obj-$(CONFIG_RTC_DRV_GAMECUBE) += rtc-gamecube.o +obj-$(CONFIG_RTC_DRV_NCT3018Y) += rtc-nct3018y.o obj-$(CONFIG_RTC_DRV_NTXEC) += rtc-ntxec.o obj-$(CONFIG_RTC_DRV_OMAP) += rtc-omap.o obj-$(CONFIG_RTC_DRV_OPAL) += rtc-opal.o diff --git a/drivers/rtc/rtc-nct3018y.c b/drivers/rtc/rtc-nct3018y.c new file mode 100644 index 000000000000..fb7fb8f5266d --- /dev/null +++ b/drivers/rtc/rtc-nct3018y.c @@ -0,0 +1,599 @@ +// 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_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_CLKO_F_MASK 0x03 /* frequenc mask */ +#define NCT3018Y_REG_CLKO_CKE 0x80 /* clock out enabled */ + +static struct i2c_driver nct3018y_driver; + +struct nct3018y { + struct rtc_device *rtc; + struct i2c_client *client; + struct gpio_desc *wakeup_host; +#ifdef CONFIG_COMMON_CLK + struct clk_hw clkout_hw; +#endif +}; + +static int nct3018y_read_block_data(struct i2c_client *client, + unsigned char reg, unsigned char length, unsigned char *buf) +{ + struct i2c_msg msgs[] = { + {/* setup read ptr */ + .addr = client->addr, + .len = 1, + .buf = ®, + }, + { + .addr = client->addr, + .flags = I2C_M_RD, + .len = length, + .buf = buf + }, + }; + + if ((i2c_transfer(client->adapter, msgs, 2)) != 2) { + dev_err(&client->dev, "%s: read error\n", __func__); + return -EIO; + } + + return 0; +} + +static int nct3018y_write_block_data(struct i2c_client *client, + unsigned char reg, unsigned char length, + unsigned char *buf) +{ + int i, err; + + for (i = 0; i < length; i++) { + unsigned char data[2] = { reg + i, buf[i] }; + + err = i2c_master_send(client, data, sizeof(data)); + if (err != sizeof(data)) { + dev_err(&client->dev, "%s: err=%d addr=%02x, data=%02x\n", __func__, + err, data[0], data[1]); + return -EIO; + } + } + + return 0; +} + +static int nct3018y_set_alarm_mode(struct i2c_client *client, bool on) +{ + unsigned char buf; + int err; + + dev_dbg(&client->dev, "%s:on:%d\n", __func__, on); + err = nct3018y_read_block_data(client, NCT3018Y_REG_CTRL, 1, &buf); + if (err < 0) + return err; + + if (on) + buf |= NCT3018Y_BIT_AIE; + else + buf &= ~NCT3018Y_BIT_AIE; + + buf |= NCT3018Y_BIT_CIE; + err = nct3018y_write_block_data(client, NCT3018Y_REG_CTRL, 1, &buf); + if (err < 0) { + dev_err(&client->dev, "%s: write NCT3018Y_REG_ST error\n", __func__); + return -EIO; + } + + err = nct3018y_read_block_data(client, NCT3018Y_REG_ST, 1, &buf); + if (err < 0) + return err; + + buf &= ~(NCT3018Y_BIT_AF); + err = nct3018y_write_block_data(client, NCT3018Y_REG_ST, 1, &buf); + if (err < 0) { + dev_err(&client->dev, "%s: write NCT3018Y_REG_ST error\n", __func__); + return -EIO; + } + + return 0; +} + +static int nct3018y_get_alarm_mode(struct i2c_client *client, unsigned char *alarm_enable, + unsigned char *alarm_flag) +{ + unsigned char buf; + int err; + + if (alarm_enable) { + dev_dbg(&client->dev, "%s:NCT3018Y_REG_CTRL\n", __func__); + err = nct3018y_read_block_data(client, NCT3018Y_REG_CTRL, 1, &buf); + if (err) + return err; + *alarm_enable = buf & NCT3018Y_BIT_AIE; + } + + if (alarm_flag) { + dev_dbg(&client->dev, "%s:NCT3018Y_REG_ST\n", __func__); + err = nct3018y_read_block_data(client, NCT3018Y_REG_ST, 1, &buf); + if (err) + return err; + *alarm_flag = buf & NCT3018Y_BIT_AF; + } + + dev_dbg(&client->dev, "%s:alarm_enable:%x alarm_flag:%x\n", + __func__, *alarm_enable, *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, 1); + 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); + struct nct3018y *nct3018y = i2c_get_clientdata(client); + unsigned char buf[10]; + int err; + + err = nct3018y_read_block_data(client, NCT3018Y_REG_ST, 1, buf); + if (err) + return err; + + if (!buf[0]) { + dev_err(&client->dev, " voltage <=1.7, date/time is not reliable.\n"); + return -EINVAL; + } + + err = nct3018y_read_block_data(client, NCT3018Y_REG_SC, 10, buf); + if (err) + return err; + + tm->tm_sec = bcd2bin(buf[0] & 0x7F); + tm->tm_min = bcd2bin(buf[2] & 0x7F); + tm->tm_hour = bcd2bin(buf[4] & 0x3F); /* rtc hr 0-24 */ + tm->tm_wday = buf[6] & 0x07; + tm->tm_mday = bcd2bin(buf[7] & 0x3F); + tm->tm_mon = bcd2bin(buf[8] & 0x1F) - 1 ; /* rtc mn 1-12 */ + tm->tm_year = bcd2bin(buf[9]) + 100; + + dev_dbg(&client->dev, "%s:s=%d, m=%d, hr=%d, md=%d, m=%d, yr=%d, wd=%d\n", + __func__, tm->tm_sec, tm->tm_min, tm->tm_hour, tm->tm_mday, tm->tm_mon, + tm->tm_year, tm->tm_wday); + + 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 = i2c_get_clientdata(client); + unsigned char buf[10] = {0}; + int err; + + dev_dbg(&client->dev, "%s:s=%d, m=%d, hr=%d, md=%d, m=%d, yr=%d, wd=%d\n", + __func__, tm->tm_sec, tm->tm_min, tm->tm_hour, tm->tm_mday, tm->tm_mon, + tm->tm_year, tm->tm_wday); + + err = nct3018y_read_block_data(client, NCT3018Y_REG_CTRL, 1, buf); + if (err) + return err; + + if (!(buf[0] & NCT3018Y_BIT_TWO)) { + dev_err(&client->dev, + " TWO is not set.\n"); + return -EINVAL; + } + + /* hours, minutes and seconds */ + buf[NCT3018Y_REG_SC] = bin2bcd(tm->tm_sec); + buf[NCT3018Y_REG_MN] = bin2bcd(tm->tm_min); + buf[NCT3018Y_REG_HR] = bin2bcd(tm->tm_hour); + buf[NCT3018Y_REG_DW] = tm->tm_wday & 0x07; + buf[NCT3018Y_REG_DM] = bin2bcd(tm->tm_mday); + + /* month, 1 - 12 */ + buf[NCT3018Y_REG_MO] = bin2bcd(tm->tm_mon+1); + + /* year and century */ + buf[NCT3018Y_REG_YR] = bin2bcd(tm->tm_year - 100); + + return nct3018y_write_block_data(client, NCT3018Y_REG_SC, 10, buf); +} + +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 = nct3018y_read_block_data(client, NCT3018Y_REG_SCA, 5, buf); + if (err) + return err; + + 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); + struct nct3018y *nct3018y = i2c_get_clientdata(client); + unsigned char buf[3]; + 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); + + buf[0] = bin2bcd(tm->time.tm_sec); + buf[1] = bin2bcd(tm->time.tm_min); + buf[2] = bin2bcd(tm->time.tm_hour); + + err = nct3018y_write_block_data(client, NCT3018Y_REG_SCA, 1, buf); + if (err) + return err; + + err = nct3018y_write_block_data(client, NCT3018Y_REG_MNA, 1, buf+1); + if (err) + return err; + + err = nct3018y_write_block_data(client, NCT3018Y_REG_HRA, 1, buf+2); + if (err) + return err; + + return nct3018y_set_alarm_mode(client, tm->enabled); +} + +static int nct3018y_irq_enable(struct device *dev, unsigned int enabled) +{ + struct i2c_client *client = to_i2c_client(dev); + struct nct3018y *nct3018y = i2c_get_clientdata(client); + + dev_dbg(dev, "%s: alarm enable=%d\n", __func__, enabled); + + return nct3018y_set_alarm_mode(to_i2c_client(dev), enabled); +} + +#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; + unsigned char buf; + int ret = nct3018y_read_block_data(client, NCT3018Y_REG_CLKO, 1, &buf); + + if (ret < 0) + return 0; + + buf &= NCT3018Y_REG_CLKO_F_MASK; + return clkout_rates[buf]; +} + +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; + unsigned char buf; + int ret = nct3018y_read_block_data(client, NCT3018Y_REG_CLKO, 1, &buf); + int i; + + if (ret < 0) + return ret; + + for (i = 0; i < ARRAY_SIZE(clkout_rates); i++) + if (clkout_rates[i] == rate) { + buf &= ~NCT3018Y_REG_CLKO_F_MASK; + buf |= i; + ret = nct3018y_write_block_data(client, NCT3018Y_REG_CLKO, 1, &buf); + return ret; + } + + 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; + unsigned char buf; + int ret = nct3018y_read_block_data(client, NCT3018Y_REG_CLKO, 1, &buf); + + if (ret < 0) + return ret; + + if (enable) + buf |= NCT3018Y_REG_CLKO_CKE; + else + buf &= ~NCT3018Y_REG_CLKO_CKE; + + ret = nct3018y_write_block_data(client, NCT3018Y_REG_CLKO, 1, &buf); + return ret; +} + +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; + unsigned char buf; + int ret = nct3018y_read_block_data(client, NCT3018Y_REG_CLKO, 1, &buf); + + if (ret < 0) + return ret; + + return buf & 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; + int ret; + unsigned char buf; + + /* disable the clkout output */ + buf = 0; + ret = nct3018y_write_block_data(client, NCT3018Y_REG_CLKO, 1, &buf); + if (ret < 0) + return ERR_PTR(ret); + + 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, +}; + +static int nct3018y_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct nct3018y *nct3018y; + int err; + unsigned char buf; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { + dev_err(&client->dev, "%s: ENODEV\n", __func__); + 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); + + err = nct3018y_read_block_data(client, NCT3018Y_REG_CTRL, 1, &buf); + if (err < 0) { + dev_err(&client->dev, "%s: read error\n", __func__); + return err; + } else if (buf & NCT3018Y_BIT_TWO) { + dev_dbg(&client->dev, "%s: NCT3018Y_BIT_TWO is :%d\n", + __func__, buf & NCT3018Y_BIT_TWO); + } + + buf = 0 | NCT3018Y_BIT_TWO; + err = nct3018y_write_block_data(client, NCT3018Y_REG_CTRL, 1, &buf); + if (err < 0) { + dev_err(&client->dev, "%s: write fail, so ReadOnly\n", __func__); + } else { + buf = 0; + err = nct3018y_write_block_data(client, NCT3018Y_REG_ST, 1, &buf); + if (err < 0) { + dev_err(&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->uie_unsupported = 1; + nct3018y->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000; + nct3018y->rtc->range_max = RTC_TIMESTAMP_END_2099; + nct3018y->rtc->set_start_time = true; + + nct3018y->wakeup_host = devm_gpiod_get(&client->dev, "host-wakeup", GPIOD_IN); + if (IS_ERR(nct3018y->wakeup_host)) { + err = PTR_ERR(nct3018y->wakeup_host); + dev_err(&client->dev, "could not get host wakeup gpio: %d", err); + return err; + } + client->irq = gpiod_to_irq(nct3018y->wakeup_host); + + dev_dbg(&client->dev, "%s: client->irq:%d\n", __func__, client->irq); + + if (client->irq > 0) { + err = devm_request_threaded_irq(&client->dev, client->irq, + NULL, nct3018y_irq, + IRQF_ONESHOT | IRQF_TRIGGER_FALLING, + nct3018y_driver.driver.name, client); + if (err) { + dev_err(&client->dev, "unable to request IRQ %d\n", client->irq); + return err; + } + } + + err = rtc_register_device(nct3018y->rtc); + if (err) + return err; + +#ifdef CONFIG_COMMON_CLK + /* register clk in common clk framework */ + nct3018y_clkout_register_clk(nct3018y); +#endif + + return 0; +} + +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 = of_match_ptr(nct3018y_of_match), + }, + .probe = nct3018y_probe, + .id_table = nct3018y_id, +}; + +module_i2c_driver(nct3018y_driver); + +MODULE_AUTHOR("Medad CChien <ctcchien@xxxxxxxxxxx>"); +MODULE_DESCRIPTION("Nuvoton NCT3018Y RTC driver"); +MODULE_LICENSE("GPL v2"); -- 2.17.1