[linux-block.git] / drivers / rtc / rtc-nct3018y.c

// 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_BAT_MASK		0x07
#define NCT3018Y_REG_CLKO_F_MASK	0x03 /* frequenc mask */
#define NCT3018Y_REG_CLKO_CKE		0x80 /* clock out enabled */

struct nct3018y {
	struct rtc_device *rtc;
	struct i2c_client *client;
#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;
	}

	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_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, 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);
	unsigned char buf[4] = {0};
	int 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;
	}

	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__);
	}

	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;
	}

	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 = of_match_ptr(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");
Commit	Line	Data
5adbaed1 ML	1	// SPDX-License-Identifier: GPL-2.0
	2	// Copyright (c) 2022 Nuvoton Technology Corporation
	3
	4	#include <linux/bcd.h>
	5	#include <linux/clk-provider.h>
	6	#include <linux/err.h>
	7	#include <linux/i2c.h>
	8	#include <linux/module.h>
	9	#include <linux/of.h>
	10	#include <linux/rtc.h>
	11	#include <linux/slab.h>
	12
	13	#define NCT3018Y_REG_SC 0x00 /* seconds */
	14	#define NCT3018Y_REG_SCA 0x01 /* alarm */
	15	#define NCT3018Y_REG_MN 0x02
	16	#define NCT3018Y_REG_MNA 0x03 /* alarm */
	17	#define NCT3018Y_REG_HR 0x04
	18	#define NCT3018Y_REG_HRA 0x05 /* alarm */
	19	#define NCT3018Y_REG_DW 0x06
	20	#define NCT3018Y_REG_DM 0x07
	21	#define NCT3018Y_REG_MO 0x08
	22	#define NCT3018Y_REG_YR 0x09
	23	#define NCT3018Y_REG_CTRL 0x0A /* timer control */
	24	#define NCT3018Y_REG_ST 0x0B /* status */
	25	#define NCT3018Y_REG_CLKO 0x0C /* clock out */
	26
	27	#define NCT3018Y_BIT_AF BIT(7)
	28	#define NCT3018Y_BIT_ST BIT(7)
	29	#define NCT3018Y_BIT_DM BIT(6)
	30	#define NCT3018Y_BIT_HF BIT(5)
	31	#define NCT3018Y_BIT_DSM BIT(4)
	32	#define NCT3018Y_BIT_AIE BIT(3)
	33	#define NCT3018Y_BIT_OFIE BIT(2)
	34	#define NCT3018Y_BIT_CIE BIT(1)
	35	#define NCT3018Y_BIT_TWO BIT(0)
	36
	37	#define NCT3018Y_REG_BAT_MASK 0x07
	38	#define NCT3018Y_REG_CLKO_F_MASK 0x03 /* frequenc mask */
	39	#define NCT3018Y_REG_CLKO_CKE 0x80 /* clock out enabled */
	40
	41	struct nct3018y {
	42	struct rtc_device *rtc;
	43	struct i2c_client *client;
	44	#ifdef CONFIG_COMMON_CLK
	45	struct clk_hw clkout_hw;
	46	#endif
	47	};
	48
	49	static int nct3018y_set_alarm_mode(struct i2c_client *client, bool on)
	50	{
	51	int err, flags;
	52
	53	dev_dbg(&client->dev, "%s:on:%d\n", __func__, on);
	54
	55	flags = i2c_smbus_read_byte_data(client, NCT3018Y_REG_CTRL);
	56	if (flags < 0) {
	57	dev_dbg(&client->dev,
	58	"Failed to read NCT3018Y_REG_CTRL\n");
	59	return flags;
	60	}
	61
	62	if (on)
	63	flags \|= NCT3018Y_BIT_AIE;
	64	else
65	flags &= ~NCT3018Y_BIT_AIE;
66
67	flags \|= NCT3018Y_BIT_CIE;
68	err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_CTRL, flags);
69	if (err < 0) {
70	dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_CTRL\n");
71	return err;
72	}
73
74	flags = i2c_smbus_read_byte_data(client, NCT3018Y_REG_ST);
75	if (flags < 0) {
76	dev_dbg(&client->dev,
77	"Failed to read NCT3018Y_REG_ST\n");
78	return flags;
79	}
80
81	flags &= ~(NCT3018Y_BIT_AF);
82	err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_ST, flags);
83	if (err < 0) {
84	dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_ST\n");
85	return err;
86	}
87
88	return 0;
89	}
90
91	static int nct3018y_get_alarm_mode(struct i2c_client client, unsigned char alarm_enable,
92	unsigned char *alarm_flag)
93	{
94	int flags;
95
96	if (alarm_enable) {
97	dev_dbg(&client->dev, "%s:NCT3018Y_REG_CTRL\n", __func__);
98	flags = i2c_smbus_read_byte_data(client, NCT3018Y_REG_CTRL);
99	if (flags < 0)
100	return flags;
101	*alarm_enable = flags & NCT3018Y_BIT_AIE;
102	}
103
104	if (alarm_flag) {
105	dev_dbg(&client->dev, "%s:NCT3018Y_REG_ST\n", __func__);
106	flags = i2c_smbus_read_byte_data(client, NCT3018Y_REG_ST);
107	if (flags < 0)
108	return flags;
109	*alarm_flag = flags & NCT3018Y_BIT_AF;
110	}
111
112	dev_dbg(&client->dev, "%s:alarm_enable:%x alarm_flag:%x\n",
113	__func__, alarm_enable, alarm_flag);
114
115	return 0;
116	}
117
118	static irqreturn_t nct3018y_irq(int irq, void *dev_id)
119	{
120	struct nct3018y *nct3018y = i2c_get_clientdata(dev_id);
121	struct i2c_client *client = nct3018y->client;
122	int err;
123	unsigned char alarm_flag;
124	unsigned char alarm_enable;
125
126	dev_dbg(&client->dev, "%s:irq:%d\n", __func__, irq);
127	err = nct3018y_get_alarm_mode(nct3018y->client, &alarm_enable, &alarm_flag);
128	if (err)
129	return IRQ_NONE;
130
131	if (alarm_flag) {
132	dev_dbg(&client->dev, "%s:alarm flag:%x\n",
133	__func__, alarm_flag);
134	rtc_update_irq(nct3018y->rtc, 1, RTC_IRQF \| RTC_AF);
135	nct3018y_set_alarm_mode(nct3018y->client, 0);
136	dev_dbg(&client->dev, "%s:IRQ_HANDLED\n", __func__);
137	return IRQ_HANDLED;
138	}
139
140	return IRQ_NONE;
141	}
142
143	/*
144	* In the routines that deal directly with the nct3018y hardware, we use
145	* rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch.
146	*/
147	static int nct3018y_rtc_read_time(struct device dev, struct rtc_time tm)
148	{
149	struct i2c_client *client = to_i2c_client(dev);
150	unsigned char buf[10];
151	int err;
152
153	err = i2c_smbus_read_i2c_block_data(client, NCT3018Y_REG_ST, 1, buf);
154	if (err < 0)
155	return err;
156
157	if (!buf[0]) {
158	dev_dbg(&client->dev, " voltage <=1.7, date/time is not reliable.\n");
159	return -EINVAL;
160	}
161
162	err = i2c_smbus_read_i2c_block_data(client, NCT3018Y_REG_SC, sizeof(buf), buf);
163	if (err < 0)
164	return err;
165
166	tm->tm_sec = bcd2bin(buf[0] & 0x7F);
167	tm->tm_min = bcd2bin(buf[2] & 0x7F);
168	tm->tm_hour = bcd2bin(buf[4] & 0x3F);
169	tm->tm_wday = buf[6] & 0x07;
170	tm->tm_mday = bcd2bin(buf[7] & 0x3F);
171	tm->tm_mon = bcd2bin(buf[8] & 0x1F) - 1;
172	tm->tm_year = bcd2bin(buf[9]) + 100;
173
174	return 0;
175	}
176
177	static int nct3018y_rtc_set_time(struct device dev, struct rtc_time tm)
178	{
179	struct i2c_client *client = to_i2c_client(dev);
180	unsigned char buf[4] = {0};
181	int err;
182
183	buf[0] = bin2bcd(tm->tm_sec);
184	err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_SC, buf[0]);
185	if (err < 0) {
186	dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_SC\n");
187	return err;
188	}
189
190	buf[0] = bin2bcd(tm->tm_min);
191	err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_MN, buf[0]);
192	if (err < 0) {
193	dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_MN\n");
194	return err;
195	}
196
197	buf[0] = bin2bcd(tm->tm_hour);
198	err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_HR, buf[0]);
199	if (err < 0) {
200	dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_HR\n");
201	return err;
202	}
203
204	buf[0] = tm->tm_wday & 0x07;
205	buf[1] = bin2bcd(tm->tm_mday);
206	buf[2] = bin2bcd(tm->tm_mon + 1);
207	buf[3] = bin2bcd(tm->tm_year - 100);
208	err = i2c_smbus_write_i2c_block_data(client, NCT3018Y_REG_DW,
209	sizeof(buf), buf);
210	if (err < 0) {
211	dev_dbg(&client->dev, "Unable to write for day and mon and year\n");
212	return -EIO;
213	}
214
215	return err;
216	}
217
218	static int nct3018y_rtc_read_alarm(struct device dev, struct rtc_wkalrm tm)
219	{
220	struct i2c_client *client = to_i2c_client(dev);
221	unsigned char buf[5];
222	int err;
223
224	err = i2c_smbus_read_i2c_block_data(client, NCT3018Y_REG_SCA,
225	sizeof(buf), buf);
226	if (err < 0) {
227	dev_dbg(&client->dev, "Unable to read date\n");
228	return -EIO;
229	}
230
231	dev_dbg(&client->dev, "%s: raw data is sec=%02x, min=%02x hr=%02x\n",
232	__func__, buf[0], buf[2], buf[4]);
233
234	tm->time.tm_sec = bcd2bin(buf[0] & 0x7F);
235	tm->time.tm_min = bcd2bin(buf[2] & 0x7F);
236	tm->time.tm_hour = bcd2bin(buf[4] & 0x3F);
237
238	err = nct3018y_get_alarm_mode(client, &tm->enabled, &tm->pending);
239	if (err < 0)
240	return err;
241
242	dev_dbg(&client->dev, "%s:s=%d m=%d, hr=%d, enabled=%d, pending=%d\n",
243	__func__, tm->time.tm_sec, tm->time.tm_min,
244	tm->time.tm_hour, tm->enabled, tm->pending);
245
246	return 0;
247	}
248
249	static int nct3018y_rtc_set_alarm(struct device dev, struct rtc_wkalrm tm)
250	{
251	struct i2c_client *client = to_i2c_client(dev);
252	int err;
253
254	dev_dbg(dev, "%s, sec=%d, min=%d hour=%d tm->enabled:%d\n",
255	__func__, tm->time.tm_sec, tm->time.tm_min, tm->time.tm_hour,
256	tm->enabled);
257
258	err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_SCA, bin2bcd(tm->time.tm_sec));
259	if (err < 0) {
260	dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_SCA\n");
261	return err;
262	}
263
264	err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_MNA, bin2bcd(tm->time.tm_min));
265	if (err < 0) {
266	dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_MNA\n");
267	return err;
268	}
269
270	err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_HRA, bin2bcd(tm->time.tm_hour));
271	if (err < 0) {
272	dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_HRA\n");
273	return err;
274	}
275
276	return nct3018y_set_alarm_mode(client, tm->enabled);
277	}
278
279	static int nct3018y_irq_enable(struct device *dev, unsigned int enabled)
280	{
281	dev_dbg(dev, "%s: alarm enable=%d\n", __func__, enabled);
282
283	return nct3018y_set_alarm_mode(to_i2c_client(dev), enabled);
284	}
285
286	static int nct3018y_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
287	{
288	struct i2c_client *client = to_i2c_client(dev);
289	int status, flags = 0;
290
291	switch (cmd) {
292	case RTC_VL_READ:
293	status = i2c_smbus_read_byte_data(client, NCT3018Y_REG_ST);
294	if (status < 0)
295	return status;
296
297	if (!(status & NCT3018Y_REG_BAT_MASK))
298	flags \|= RTC_VL_DATA_INVALID;
299
300	return put_user(flags, (unsigned int __user *)arg);
301
302	default:
303	return -ENOIOCTLCMD;
304	}
305	}
306
307	#ifdef CONFIG_COMMON_CLK
308	/*
309	* Handling of the clkout
310	*/
311
312	#define clkout_hw_to_nct3018y(_hw) container_of(_hw, struct nct3018y, clkout_hw)
313
314	static const int clkout_rates[] = {
315	32768,
316	1024,
317	32,
318	1,
319	};
320
321	static unsigned long nct3018y_clkout_recalc_rate(struct clk_hw *hw,
322	unsigned long parent_rate)
323	{
324	struct nct3018y *nct3018y = clkout_hw_to_nct3018y(hw);
325	struct i2c_client *client = nct3018y->client;
326	int flags;
327
328	flags = i2c_smbus_read_byte_data(client, NCT3018Y_REG_CLKO);
329	if (flags < 0)
330	return 0;
331
332	flags &= NCT3018Y_REG_CLKO_F_MASK;
333	return clkout_rates[flags];
334	}
335
336	static long nct3018y_clkout_round_rate(struct clk_hw *hw, unsigned long rate,
337	unsigned long *prate)
338	{
339	int i;
340
341	for (i = 0; i < ARRAY_SIZE(clkout_rates); i++)
342	if (clkout_rates[i] <= rate)
343	return clkout_rates[i];
344
345	return 0;
346	}
347
348	static int nct3018y_clkout_set_rate(struct clk_hw *hw, unsigned long rate,
349	unsigned long parent_rate)
350	{
351	struct nct3018y *nct3018y = clkout_hw_to_nct3018y(hw);
352	struct i2c_client *client = nct3018y->client;
353	int i, flags;
354
355	flags = i2c_smbus_read_byte_data(client, NCT3018Y_REG_CLKO);
356	if (flags < 0)
357	return flags;
358
359	for (i = 0; i < ARRAY_SIZE(clkout_rates); i++)
360	if (clkout_rates[i] == rate) {
361	flags &= ~NCT3018Y_REG_CLKO_F_MASK;
362	flags \|= i;
363	return i2c_smbus_write_byte_data(client, NCT3018Y_REG_CLKO, flags);
364	}
365
366	return -EINVAL;
367	}
368
369	static int nct3018y_clkout_control(struct clk_hw *hw, bool enable)
370	{
371	struct nct3018y *nct3018y = clkout_hw_to_nct3018y(hw);
372	struct i2c_client *client = nct3018y->client;
373	int flags;
374
375	flags = i2c_smbus_read_byte_data(client, NCT3018Y_REG_CLKO);
376	if (flags < 0)
377	return flags;
378
379	if (enable)
380	flags \|= NCT3018Y_REG_CLKO_CKE;
381	else
382	flags &= ~NCT3018Y_REG_CLKO_CKE;
383
384	return i2c_smbus_write_byte_data(client, NCT3018Y_REG_CLKO, flags);
385	}
386
387	static int nct3018y_clkout_prepare(struct clk_hw *hw)
388	{
389	return nct3018y_clkout_control(hw, 1);
390	}
391
392	static void nct3018y_clkout_unprepare(struct clk_hw *hw)
393	{
394	nct3018y_clkout_control(hw, 0);
395	}
396
397	static int nct3018y_clkout_is_prepared(struct clk_hw *hw)
398	{
399	struct nct3018y *nct3018y = clkout_hw_to_nct3018y(hw);
400	struct i2c_client *client = nct3018y->client;
401	int flags;
402
403	flags = i2c_smbus_read_byte_data(client, NCT3018Y_REG_CLKO);
404	if (flags < 0)
405	return flags;
406
407	return flags & NCT3018Y_REG_CLKO_CKE;
408	}
409
410	static const struct clk_ops nct3018y_clkout_ops = {
411	.prepare = nct3018y_clkout_prepare,
412	.unprepare = nct3018y_clkout_unprepare,
413	.is_prepared = nct3018y_clkout_is_prepared,
414	.recalc_rate = nct3018y_clkout_recalc_rate,
415	.round_rate = nct3018y_clkout_round_rate,
416	.set_rate = nct3018y_clkout_set_rate,
417	};
418
419	static struct clk nct3018y_clkout_register_clk(struct nct3018y nct3018y)
420	{
421	struct i2c_client *client = nct3018y->client;
422	struct device_node *node = client->dev.of_node;
423	struct clk *clk;
424	struct clk_init_data init;
425
426	init.name = "nct3018y-clkout";
427	init.ops = &nct3018y_clkout_ops;
428	init.flags = 0;
429	init.parent_names = NULL;
430	init.num_parents = 0;
431	nct3018y->clkout_hw.init = &init;
432
433	/* optional override of the clockname */
434	of_property_read_string(node, "clock-output-names", &init.name);
435
436	/* register the clock */
437	clk = devm_clk_register(&client->dev, &nct3018y->clkout_hw);
438
439	if (!IS_ERR(clk))
440	of_clk_add_provider(node, of_clk_src_simple_get, clk);
441
442	return clk;
443	}
444	#endif
445
446	static const struct rtc_class_ops nct3018y_rtc_ops = {
447	.read_time = nct3018y_rtc_read_time,
448	.set_time = nct3018y_rtc_set_time,
449	.read_alarm = nct3018y_rtc_read_alarm,
450	.set_alarm = nct3018y_rtc_set_alarm,
451	.alarm_irq_enable = nct3018y_irq_enable,
452	.ioctl = nct3018y_ioctl,
453	};
454
c050dedb	455	static int nct3018y_probe(struct i2c_client *client)
5adbaed1 ML	456	{
	457	struct nct3018y *nct3018y;
	458	int err, flags;
	459
	460	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C \|
	461	I2C_FUNC_SMBUS_BYTE \|
	462	I2C_FUNC_SMBUS_BLOCK_DATA))
	463	return -ENODEV;
	464
	465	nct3018y = devm_kzalloc(&client->dev, sizeof(struct nct3018y),
	466	GFP_KERNEL);
	467	if (!nct3018y)
	468	return -ENOMEM;
	469
	470	i2c_set_clientdata(client, nct3018y);
	471	nct3018y->client = client;
	472	device_set_wakeup_capable(&client->dev, 1);
	473
	474	flags = i2c_smbus_read_byte_data(client, NCT3018Y_REG_CTRL);
	475	if (flags < 0) {
	476	dev_dbg(&client->dev, "%s: read error\n", __func__);
	477	return flags;
	478	} else if (flags & NCT3018Y_BIT_TWO) {
	479	dev_dbg(&client->dev, "%s: NCT3018Y_BIT_TWO is set\n", __func__);
	480	}
	481
	482	flags = NCT3018Y_BIT_TWO;
	483	err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_CTRL, flags);
	484	if (err < 0) {
	485	dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_CTRL\n");
	486	return err;
	487	}
	488
	489	flags = 0;
	490	err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_ST, flags);
	491	if (err < 0) {
	492	dev_dbg(&client->dev, "%s: write error\n", __func__);
	493	return err;
	494	}
	495
	496	nct3018y->rtc = devm_rtc_allocate_device(&client->dev);
	497	if (IS_ERR(nct3018y->rtc))
	498	return PTR_ERR(nct3018y->rtc);
	499
	500	nct3018y->rtc->ops = &nct3018y_rtc_ops;
	501	nct3018y->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
	502	nct3018y->rtc->range_max = RTC_TIMESTAMP_END_2099;
	503
	504	if (client->irq > 0) {
	505	err = devm_request_threaded_irq(&client->dev, client->irq,
	506	NULL, nct3018y_irq,
	507	IRQF_ONESHOT \| IRQF_TRIGGER_FALLING,
	508	"nct3018y", client);
	509	if (err) {
	510	dev_dbg(&client->dev, "unable to request IRQ %d\n", client->irq);
	511	return err;
	512	}
	513	} else {
	514	clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, nct3018y->rtc->features);
	515	clear_bit(RTC_FEATURE_ALARM, nct3018y->rtc->features);
	516	}
	517
	518	#ifdef CONFIG_COMMON_CLK
	519	/* register clk in common clk framework */
520	nct3018y_clkout_register_clk(nct3018y);
521	#endif
522
523	return devm_rtc_register_device(nct3018y->rtc);
524	}
525
526	static const struct i2c_device_id nct3018y_id[] = {
527	{ "nct3018y", 0 },
528	{ }
529	};
530	MODULE_DEVICE_TABLE(i2c, nct3018y_id);
531
532	static const struct of_device_id nct3018y_of_match[] = {
533	{ .compatible = "nuvoton,nct3018y" },
534	{}
535	};
536	MODULE_DEVICE_TABLE(of, nct3018y_of_match);
537
538	static struct i2c_driver nct3018y_driver = {
539	.driver = {
540	.name = "rtc-nct3018y",
541	.of_match_table = of_match_ptr(nct3018y_of_match),
542	},
31b0cecb	543	.probe = nct3018y_probe,
5adbaed1 ML	544	.id_table = nct3018y_id,
	545	};
	546
	547	module_i2c_driver(nct3018y_driver);
	548
	549	MODULE_AUTHOR("Medad CChien <ctcchien@nuvoton.com>");
	550	MODULE_AUTHOR("Mia Lin <mimi05633@gmail.com>");
	551	MODULE_DESCRIPTION("Nuvoton NCT3018Y RTC driver");
	552	MODULE_LICENSE("GPL");