Commit dcaf0384 authored by Heiko Stuebner's avatar Heiko Stuebner Committed by Linus Torvalds
Browse files

rtc: add hym8563 rtc-driver 



The Haoyu Microelectronics HYM8563 provides rtc and alarm functions as
well as a clock output of up to 32kHz.

Signed-off-by: default avatarHeiko Stuebner <heiko@sntech.de>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Richard Weinberger <richard.weinberger@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent b7ed189d

drivers/rtc/Kconfig

+11 −0
Original line number Diff line number Diff line
@@ -212,6 +212,17 @@ config RTC_DRV_DS3232 
	  This driver can also be built as a module.  If so, the module

	  will be called rtc-ds3232.



config RTC_DRV_HYM8563

	tristate "Haoyu Microelectronics HYM8563"

	depends on I2C && OF

	help

	  Say Y to enable support for the HYM8563 I2C RTC chip. Apart

	  from the usual rtc functions it provides a clock output of

	  up to 32kHz.



	  This driver can also be built as a module. If so, the module

	  will be called rtc-hym8563.



config RTC_DRV_LP8788

	tristate "TI LP8788 RTC driver"

	depends on MFD_LP8788

drivers/rtc/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -55,6 +55,7 @@ obj-$(CONFIG_RTC_DRV_EP93XX) += rtc-ep93xx.o 
obj-$(CONFIG_RTC_DRV_FM3130)	+= rtc-fm3130.o

obj-$(CONFIG_RTC_DRV_GENERIC)	+= rtc-generic.o

obj-$(CONFIG_RTC_DRV_HID_SENSOR_TIME) += rtc-hid-sensor-time.o

obj-$(CONFIG_RTC_DRV_HYM8563)	+= rtc-hym8563.o

obj-$(CONFIG_RTC_DRV_IMXDI)	+= rtc-imxdi.o

obj-$(CONFIG_RTC_DRV_ISL1208)	+= rtc-isl1208.o

obj-$(CONFIG_RTC_DRV_ISL12022)	+= rtc-isl12022.o

drivers/rtc/rtc-hym8563.c

0 → 100644
+606 −0
Original line number Diff line number Diff line 
/*

 * Haoyu HYM8563 RTC driver

 *

 * Copyright (C) 2013 MundoReader S.L.

 * Author: Heiko Stuebner <heiko@sntech.de>

 *

 * based on rtc-HYM8563

 * Copyright (C) 2010 ROCKCHIP, Inc.

 *

 * This software is licensed under the terms of the GNU General Public

 * License version 2, as published by the Free Software Foundation, and

 * may be copied, distributed, and modified under those terms.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 */



#include <linux/module.h>

#include <linux/clk-provider.h>

#include <linux/i2c.h>

#include <linux/bcd.h>

#include <linux/rtc.h>



#define HYM8563_CTL1		0x00

#define HYM8563_CTL1_TEST	BIT(7)

#define HYM8563_CTL1_STOP	BIT(5)

#define HYM8563_CTL1_TESTC	BIT(3)



#define HYM8563_CTL2		0x01

#define HYM8563_CTL2_TI_TP	BIT(4)

#define HYM8563_CTL2_AF		BIT(3)

#define HYM8563_CTL2_TF		BIT(2)

#define HYM8563_CTL2_AIE	BIT(1)

#define HYM8563_CTL2_TIE	BIT(0)



#define HYM8563_SEC		0x02

#define HYM8563_SEC_VL		BIT(7)

#define HYM8563_SEC_MASK	0x7f



#define HYM8563_MIN		0x03

#define HYM8563_MIN_MASK	0x7f



#define HYM8563_HOUR		0x04

#define HYM8563_HOUR_MASK	0x3f



#define HYM8563_DAY		0x05

#define HYM8563_DAY_MASK	0x3f



#define HYM8563_WEEKDAY		0x06

#define HYM8563_WEEKDAY_MASK	0x07



#define HYM8563_MONTH		0x07

#define HYM8563_MONTH_CENTURY	BIT(7)

#define HYM8563_MONTH_MASK	0x1f



#define HYM8563_YEAR		0x08



#define HYM8563_ALM_MIN		0x09

#define HYM8563_ALM_HOUR	0x0a

#define HYM8563_ALM_DAY		0x0b

#define HYM8563_ALM_WEEK	0x0c



/* Each alarm check can be disabled by setting this bit in the register */

#define HYM8563_ALM_BIT_DISABLE	BIT(7)



#define HYM8563_CLKOUT		0x0d

#define HYM8563_CLKOUT_DISABLE	BIT(7)

#define HYM8563_CLKOUT_32768	0

#define HYM8563_CLKOUT_1024	1

#define HYM8563_CLKOUT_32	2

#define HYM8563_CLKOUT_1	3

#define HYM8563_CLKOUT_MASK	3



#define HYM8563_TMR_CTL		0x0e

#define HYM8563_TMR_CTL_ENABLE	BIT(7)

#define HYM8563_TMR_CTL_4096	0

#define HYM8563_TMR_CTL_64	1

#define HYM8563_TMR_CTL_1	2

#define HYM8563_TMR_CTL_1_60	3

#define HYM8563_TMR_CTL_MASK	3



#define HYM8563_TMR_CNT		0x0f



struct hym8563 {

	struct i2c_client	*client;

	struct rtc_device	*rtc;

	bool			valid;

#ifdef CONFIG_COMMON_CLK

	struct clk_hw		clkout_hw;

#endif

};



/*

 * RTC handling

 */



static int hym8563_rtc_read_time(struct device *dev, struct rtc_time *tm)

{

	struct i2c_client *client = to_i2c_client(dev);

	struct hym8563 *hym8563 = i2c_get_clientdata(client);

	u8 buf[7];

	int ret;



	if (!hym8563->valid) {

		dev_warn(&client->dev, "no valid clock/calendar values available\n");

		return -EPERM;

	}



	ret = i2c_smbus_read_i2c_block_data(client, HYM8563_SEC, 7, buf);



	tm->tm_sec = bcd2bin(buf[0] & HYM8563_SEC_MASK);

	tm->tm_min = bcd2bin(buf[1] & HYM8563_MIN_MASK);

	tm->tm_hour = bcd2bin(buf[2] & HYM8563_HOUR_MASK);

	tm->tm_mday = bcd2bin(buf[3] & HYM8563_DAY_MASK);

	tm->tm_wday = bcd2bin(buf[4] & HYM8563_WEEKDAY_MASK); /* 0 = Sun */

	tm->tm_mon = bcd2bin(buf[5] & HYM8563_MONTH_MASK) - 1; /* 0 = Jan */

	tm->tm_year = bcd2bin(buf[6]) + 100;



	return 0;

}



static int hym8563_rtc_set_time(struct device *dev, struct rtc_time *tm)

{

	struct i2c_client *client = to_i2c_client(dev);

	struct hym8563 *hym8563 = i2c_get_clientdata(client);

	u8 buf[7];

	int ret;



	/* Years >= 2100 are to far in the future, 19XX is to early */

	if (tm->tm_year < 100 || tm->tm_year >= 200)

		return -EINVAL;



	buf[0] = bin2bcd(tm->tm_sec);

	buf[1] = bin2bcd(tm->tm_min);

	buf[2] = bin2bcd(tm->tm_hour);

	buf[3] = bin2bcd(tm->tm_mday);

	buf[4] = bin2bcd(tm->tm_wday);

	buf[5] = bin2bcd(tm->tm_mon + 1);



	/*

	 * While the HYM8563 has a century flag in the month register,

	 * it does not seem to carry it over a subsequent write/read.

	 * So we'll limit ourself to 100 years, starting at 2000 for now.

	 */

	buf[6] = tm->tm_year - 100;



	/*

	 * CTL1 only contains TEST-mode bits apart from stop,

	 * so no need to read the value first

	 */

	ret = i2c_smbus_write_byte_data(client, HYM8563_CTL1,

						HYM8563_CTL1_STOP);

	if (ret < 0)

		return ret;



	ret = i2c_smbus_write_i2c_block_data(client, HYM8563_SEC, 7, buf);

	if (ret < 0)

		return ret;



	ret = i2c_smbus_write_byte_data(client, HYM8563_CTL1, 0);

	if (ret < 0)

		return ret;



	hym8563->valid = true;



	return 0;

}



static int hym8563_rtc_alarm_irq_enable(struct device *dev,

					unsigned int enabled)

{

	struct i2c_client *client = to_i2c_client(dev);

	int data;



	data = i2c_smbus_read_byte_data(client, HYM8563_CTL2);

	if (data < 0)

		return data;



	if (enabled)

		data |= HYM8563_CTL2_AIE;

	else

		data &= ~HYM8563_CTL2_AIE;



	return i2c_smbus_write_byte_data(client, HYM8563_CTL2, data);

};



static int hym8563_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)

{

	struct i2c_client *client = to_i2c_client(dev);

	struct rtc_time *alm_tm = &alm->time;

	u8 buf[4];

	int ret;



	ret = i2c_smbus_read_i2c_block_data(client, HYM8563_ALM_MIN, 4, buf);

	if (ret < 0)

		return ret;



	/* The alarm only has a minute accuracy */

	alm_tm->tm_sec = -1;



	alm_tm->tm_min = (buf[0] & HYM8563_ALM_BIT_DISABLE) ?

					-1 :

					bcd2bin(buf[0] & HYM8563_MIN_MASK);

	alm_tm->tm_hour = (buf[1] & HYM8563_ALM_BIT_DISABLE) ?

					-1 :

					bcd2bin(buf[1] & HYM8563_HOUR_MASK);

	alm_tm->tm_mday = (buf[2] & HYM8563_ALM_BIT_DISABLE) ?

					-1 :

					bcd2bin(buf[2] & HYM8563_DAY_MASK);

	alm_tm->tm_wday = (buf[3] & HYM8563_ALM_BIT_DISABLE) ?

					-1 :

					bcd2bin(buf[3] & HYM8563_WEEKDAY_MASK);



	alm_tm->tm_mon = -1;

	alm_tm->tm_year = -1;



	ret = i2c_smbus_read_byte_data(client, HYM8563_CTL2);

	if (ret < 0)

		return ret;



	if (ret & HYM8563_CTL2_AIE)

		alm->enabled = 1;



	return 0;

}



static int hym8563_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)

{

	struct i2c_client *client = to_i2c_client(dev);

	struct rtc_time *alm_tm = &alm->time;

	u8 buf[4];

	int ret;



	/*

	 * The alarm has no seconds so deal with it

	 */

	if (alm_tm->tm_sec) {

		alm_tm->tm_sec = 0;

		alm_tm->tm_min++;

		if (alm_tm->tm_min >= 60) {

			alm_tm->tm_min = 0;

			alm_tm->tm_hour++;

			if (alm_tm->tm_hour >= 24) {

				alm_tm->tm_hour = 0;

				alm_tm->tm_mday++;

				if (alm_tm->tm_mday > 31)

					alm_tm->tm_mday = 0;

			}

		}

	}



	ret = i2c_smbus_read_byte_data(client, HYM8563_CTL2);

	if (ret < 0)

		return ret;



	ret &= ~HYM8563_CTL2_AIE;



	ret = i2c_smbus_write_byte_data(client, HYM8563_CTL2, ret);

	if (ret < 0)

		return ret;



	buf[0] = (alm_tm->tm_min < 60 && alm_tm->tm_min >= 0) ?

			bin2bcd(alm_tm->tm_min) : HYM8563_ALM_BIT_DISABLE;



	buf[1] = (alm_tm->tm_hour < 24 && alm_tm->tm_hour >= 0) ?

			bin2bcd(alm_tm->tm_hour) : HYM8563_ALM_BIT_DISABLE;



	buf[2] = (alm_tm->tm_mday <= 31 && alm_tm->tm_mday >= 1) ?

			bin2bcd(alm_tm->tm_mday) : HYM8563_ALM_BIT_DISABLE;



	buf[3] = (alm_tm->tm_wday < 7 && alm_tm->tm_wday >= 0) ?

			bin2bcd(alm_tm->tm_wday) : HYM8563_ALM_BIT_DISABLE;



	ret = i2c_smbus_write_i2c_block_data(client, HYM8563_ALM_MIN, 4, buf);

	if (ret < 0)

		return ret;



	return hym8563_rtc_alarm_irq_enable(dev, alm->enabled);

}



static const struct rtc_class_ops hym8563_rtc_ops = {

	.read_time		= hym8563_rtc_read_time,

	.set_time		= hym8563_rtc_set_time,

	.alarm_irq_enable	= hym8563_rtc_alarm_irq_enable,

	.read_alarm		= hym8563_rtc_read_alarm,

	.set_alarm		= hym8563_rtc_set_alarm,

};



/*

 * Handling of the clkout

 */



#ifdef CONFIG_COMMON_CLK

#define clkout_hw_to_hym8563(_hw) container_of(_hw, struct hym8563, clkout_hw)



static int clkout_rates[] = {

	32768,

	1024,

	32,

	1,

};



static unsigned long hym8563_clkout_recalc_rate(struct clk_hw *hw,

						unsigned long parent_rate)

{

	struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw);

	struct i2c_client *client = hym8563->client;

	int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT);



	if (ret < 0 || ret & HYM8563_CLKOUT_DISABLE)

		return 0;



	ret &= HYM8563_CLKOUT_MASK;

	return clkout_rates[ret];

}



static long hym8563_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 hym8563_clkout_set_rate(struct clk_hw *hw, unsigned long rate,

				   unsigned long parent_rate)

{

	struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw);

	struct i2c_client *client = hym8563->client;

	int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT);

	int i;



	if (ret < 0)

		return ret;



	for (i = 0; i < ARRAY_SIZE(clkout_rates); i++)

		if (clkout_rates[i] == rate) {

			ret &= ~HYM8563_CLKOUT_MASK;

			ret |= i;

			return i2c_smbus_write_byte_data(client,

							 HYM8563_CLKOUT, ret);

		}



	return -EINVAL;

}



static int hym8563_clkout_control(struct clk_hw *hw, bool enable)

{

	struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw);

	struct i2c_client *client = hym8563->client;

	int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT);



	if (ret < 0)

		return ret;



	if (enable)

		ret &= ~HYM8563_CLKOUT_DISABLE;

	else

		ret |= HYM8563_CLKOUT_DISABLE;



	return i2c_smbus_write_byte_data(client, HYM8563_CLKOUT, ret);

}



static int hym8563_clkout_prepare(struct clk_hw *hw)

{

	return hym8563_clkout_control(hw, 1);

}



static void hym8563_clkout_unprepare(struct clk_hw *hw)

{

	hym8563_clkout_control(hw, 0);

}



static int hym8563_clkout_is_prepared(struct clk_hw *hw)

{

	struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw);

	struct i2c_client *client = hym8563->client;

	int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT);



	if (ret < 0)

		return ret;



	return !(ret & HYM8563_CLKOUT_DISABLE);

}



const struct clk_ops hym8563_clkout_ops = {

	.prepare = hym8563_clkout_prepare,

	.unprepare = hym8563_clkout_unprepare,

	.is_prepared = hym8563_clkout_is_prepared,

	.recalc_rate = hym8563_clkout_recalc_rate,

	.round_rate = hym8563_clkout_round_rate,

	.set_rate = hym8563_clkout_set_rate,

};



static struct clk *hym8563_clkout_register_clk(struct hym8563 *hym8563)

{

	struct i2c_client *client = hym8563->client;

	struct device_node *node = client->dev.of_node;

	struct clk *clk;

	struct clk_init_data init;

	int ret;



	ret = i2c_smbus_write_byte_data(client, HYM8563_CLKOUT,

						HYM8563_CLKOUT_DISABLE);

	if (ret < 0)

		return ERR_PTR(ret);



	init.name = "hym8563-clkout";

	init.ops = &hym8563_clkout_ops;

	init.flags = CLK_IS_ROOT;

	init.parent_names = NULL;

	init.num_parents = 0;

	hym8563->clkout_hw.init = &init;



	/* register the clock */

	clk = clk_register(&client->dev, &hym8563->clkout_hw);



	if (!IS_ERR(clk))

		of_clk_add_provider(node, of_clk_src_simple_get, clk);



	return clk;

}

#endif



/*

 * The alarm interrupt is implemented as a level-low interrupt in the

 * hym8563, while the timer interrupt uses a falling edge.

 * We don't use the timer at all, so the interrupt is requested to

 * use the level-low trigger.

 */

static irqreturn_t hym8563_irq(int irq, void *dev_id)

{

	struct hym8563 *hym8563 = (struct hym8563 *)dev_id;

	struct i2c_client *client = hym8563->client;

	struct mutex *lock = &hym8563->rtc->ops_lock;

	int data, ret;



	mutex_lock(lock);



	/* Clear the alarm flag */



	data = i2c_smbus_read_byte_data(client, HYM8563_CTL2);

	if (data < 0) {

		dev_err(&client->dev, "%s: error reading i2c data %d\n",

			__func__, data);

		goto out;

	}



	data &= ~HYM8563_CTL2_AF;



	ret = i2c_smbus_write_byte_data(client, HYM8563_CTL2, data);

	if (ret < 0) {

		dev_err(&client->dev, "%s: error writing i2c data %d\n",

			__func__, ret);

	}



out:

	mutex_unlock(lock);

	return IRQ_HANDLED;

}



static int hym8563_init_device(struct i2c_client *client)

{

	int ret;



	/* Clear stop flag if present */

	ret = i2c_smbus_write_byte_data(client, HYM8563_CTL1, 0);

	if (ret < 0)

		return ret;



	ret = i2c_smbus_read_byte_data(client, HYM8563_CTL2);

	if (ret < 0)

		return ret;



	/* Disable alarm and timer interrupts */

	ret &= ~HYM8563_CTL2_AIE;

	ret &= ~HYM8563_CTL2_TIE;



	/* Clear any pending alarm and timer flags */

	if (ret & HYM8563_CTL2_AF)

		ret &= ~HYM8563_CTL2_AF;



	if (ret & HYM8563_CTL2_TF)

		ret &= ~HYM8563_CTL2_TF;



	ret &= ~HYM8563_CTL2_TI_TP;



	return i2c_smbus_write_byte_data(client, HYM8563_CTL2, ret);

}



#ifdef CONFIG_PM_SLEEP

static int hym8563_suspend(struct device *dev)

{

	struct i2c_client *client = to_i2c_client(dev);

	int ret;



	if (device_may_wakeup(dev)) {

		ret = enable_irq_wake(client->irq);

		if (ret) {

			dev_err(dev, "enable_irq_wake failed, %d\n", ret);

			return ret;

		}

	}



	return 0;

}



static int hym8563_resume(struct device *dev)

{

	struct i2c_client *client = to_i2c_client(dev);



	if (device_may_wakeup(dev))

		disable_irq_wake(client->irq);



	return 0;

}

#endif



static SIMPLE_DEV_PM_OPS(hym8563_pm_ops, hym8563_suspend, hym8563_resume);



static int hym8563_probe(struct i2c_client *client,

			 const struct i2c_device_id *id)

{

	struct hym8563 *hym8563;

	int ret;



	hym8563 = devm_kzalloc(&client->dev, sizeof(*hym8563), GFP_KERNEL);

	if (!hym8563)

		return -ENOMEM;



	hym8563->client = client;

	i2c_set_clientdata(client, hym8563);



	device_set_wakeup_capable(&client->dev, true);



	ret = hym8563_init_device(client);

	if (ret) {

		dev_err(&client->dev, "could not init device, %d\n", ret);

		return ret;

	}



	ret = devm_request_threaded_irq(&client->dev, client->irq,

					NULL, hym8563_irq,

					IRQF_TRIGGER_LOW | IRQF_ONESHOT,

					client->name, hym8563);

	if (ret < 0) {

		dev_err(&client->dev, "irq %d request failed, %d\n",

			client->irq, ret);

		return ret;

	}



	/* check state of calendar information */

	ret = i2c_smbus_read_byte_data(client, HYM8563_SEC);

	if (ret < 0)

		return ret;



	hym8563->valid = !(ret & HYM8563_SEC_VL);

	dev_dbg(&client->dev, "rtc information is %s\n",

		hym8563->valid ? "valid" : "invalid");



	hym8563->rtc = devm_rtc_device_register(&client->dev, client->name,

						&hym8563_rtc_ops, THIS_MODULE);

	if (IS_ERR(hym8563->rtc))

		return PTR_ERR(hym8563->rtc);



#ifdef CONFIG_COMMON_CLK

	hym8563_clkout_register_clk(hym8563);

#endif



	return 0;

}



static const struct i2c_device_id hym8563_id[] = {

	{ "hym8563", 0 },

	{},

};

MODULE_DEVICE_TABLE(i2c, hym8563_id);



static struct of_device_id hym8563_dt_idtable[] = {

	{ .compatible = "haoyu,hym8563" },

	{},

};

MODULE_DEVICE_TABLE(of, hym8563_dt_idtable);



static struct i2c_driver hym8563_driver = {

	.driver		= {

		.name	= "rtc-hym8563",

		.owner	= THIS_MODULE,

		.pm	= &hym8563_pm_ops,

		.of_match_table	= of_match_ptr(hym8563_dt_idtable),

	},

	.probe		= hym8563_probe,

	.id_table	= hym8563_id,

};



module_i2c_driver(hym8563_driver);



MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");

MODULE_DESCRIPTION("HYM8563 RTC driver");

MODULE_LICENSE("GPL");

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