Patchwork [v2,2/2] rtc: add hym8563 rtc-driver

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Submitter Heiko Stübner
Date Dec. 1, 2013, 1:39 p.m.
Message ID <201312011439.45417.heiko@sntech.de>
Download mbox | patch
Permalink /patch/295688/
State New
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Heiko Stübner - Dec. 1, 2013, 1:39 p.m.
The Haoyu Microelectronics HYM8563 provides rtc- and alarm functions
as well as a clock output of up to 32kHz.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
---
 drivers/rtc/Kconfig       |   11 +
 drivers/rtc/Makefile      |    1 +
 drivers/rtc/rtc-hym8563.c |  626 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 638 insertions(+)
 create mode 100644 drivers/rtc/rtc-hym8563.c
richard -rw- weinberger - Dec. 1, 2013, 2:38 p.m.
On Sun, Dec 1, 2013 at 2:39 PM, Heiko Stübner <heiko@sntech.de> wrote:
> The Haoyu Microelectronics HYM8563 provides rtc- and alarm functions
> as well as a clock output of up to 32kHz.
>
> Signed-off-by: Heiko Stuebner <heiko@sntech.de>
> ---
>  drivers/rtc/Kconfig       |   11 +
>  drivers/rtc/Makefile      |    1 +
>  drivers/rtc/rtc-hym8563.c |  626 +++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 638 insertions(+)
>  create mode 100644 drivers/rtc/rtc-hym8563.c
>
> diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
> index 9654aa3..bf2c572 100644
> --- a/drivers/rtc/Kconfig
> +++ b/drivers/rtc/Kconfig
> @@ -202,6 +202,17 @@ 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 && GPIOLIB
> +       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
> diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
> index 2dff3d2..92f9d2c 100644
> --- a/drivers/rtc/Makefile
> +++ b/drivers/rtc/Makefile
> @@ -54,6 +54,7 @@ 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
> diff --git a/drivers/rtc/rtc-hym8563.c b/drivers/rtc/rtc-hym8563.c
> new file mode 100644
> index 0000000..2dc4154
> --- /dev/null
> +++ b/drivers/rtc/rtc-hym8563.c
> @@ -0,0 +1,626 @@
> +/*
> + * 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>
> +#include <linux/delay.h>
> +#include <linux/slab.h>
> +#include <linux/gpio.h>
> +#include <linux/of_gpio.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;
> +       struct clk_hw           clkout_hw;
> +};
> +
> +/*
> + * 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
> + */
> +
> +#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;
> +}
> +
> +/*
> + * 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, gpio_int;
> +
> +       hym8563 = devm_kzalloc(&client->dev, sizeof(hym8563), GFP_KERNEL);

Shouldn't this be sizeof(*hym8563)?

> +       if (!hym8563)
> +               return -ENOMEM;
> +
> +       hym8563->client = client;
> +       i2c_set_clientdata(client, hym8563);
> +
> +       device_set_wakeup_capable(&client->dev, true);
> +
> +       gpio_int = of_get_gpio(client->dev.of_node, 0);
> +       if (!gpio_is_valid(gpio_int)) {
> +               dev_err(&client->dev, "failed to get interrupt gpio\n");
> +               return -EINVAL;
> +       }
> +
> +       ret = devm_gpio_request_one(&client->dev, gpio_int,
> +                                     GPIOF_DIR_IN, "hym8563_int");
> +       if (ret) {
> +               dev_err(&client->dev, "request of gpio %d failed, %d\n",
> +                       gpio_int, ret);
> +               return ret;
> +       }
> +
> +       client->irq = gpio_to_irq(gpio_int);
> +       if (client->irq < 0) {
> +               dev_err(&client->dev, "could not get irq of gpio %d, %d\n",
> +                       gpio_int, client->irq);
> +               return client->irq;
> +       }
> +
> +       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);
> +
> +       if (IS_ENABLED(CONFIG_COMMON_CLK))
> +               hym8563_clkout_register_clk(hym8563);
> +
> +       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");
> --
> 1.7.10.4
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
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> Please read the FAQ at  http://www.tux.org/lkml/
Heiko Stübner - Dec. 1, 2013, 5:19 p.m.
Am Sonntag, 1. Dezember 2013, 15:38:40 schrieb Richard Weinberger:
> On Sun, Dec 1, 2013 at 2:39 PM, Heiko Stübner <heiko@sntech.de> wrote:
> > +static int hym8563_probe(struct i2c_client *client,
> > +                        const struct i2c_device_id *id)
> > +{
> > +       struct hym8563 *hym8563;
> > +       int ret, gpio_int;
> > +
> > +       hym8563 = devm_kzalloc(&client->dev, sizeof(hym8563),
> > GFP_KERNEL);
> 
> Shouldn't this be sizeof(*hym8563)?

you're right of course, thanks for catching the missing "*", I'll send a v3 
shortly.


Heiko

Patch

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 9654aa3..bf2c572 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -202,6 +202,17 @@  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 && GPIOLIB
+	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
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 2dff3d2..92f9d2c 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -54,6 +54,7 @@  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
diff --git a/drivers/rtc/rtc-hym8563.c b/drivers/rtc/rtc-hym8563.c
new file mode 100644
index 0000000..2dc4154
--- /dev/null
+++ b/drivers/rtc/rtc-hym8563.c
@@ -0,0 +1,626 @@ 
+/*
+ * 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>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/gpio.h>
+#include <linux/of_gpio.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;
+	struct clk_hw		clkout_hw;
+};
+
+/*
+ * 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
+ */
+
+#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;
+}
+
+/*
+ * 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, gpio_int;
+
+	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);
+
+	gpio_int = of_get_gpio(client->dev.of_node, 0);
+	if (!gpio_is_valid(gpio_int)) {
+		dev_err(&client->dev, "failed to get interrupt gpio\n");
+		return -EINVAL;
+	}
+
+	ret = devm_gpio_request_one(&client->dev, gpio_int,
+				      GPIOF_DIR_IN, "hym8563_int");
+	if (ret) {
+		dev_err(&client->dev, "request of gpio %d failed, %d\n",
+			gpio_int, ret);
+		return ret;
+	}
+
+	client->irq = gpio_to_irq(gpio_int);
+	if (client->irq < 0) {
+		dev_err(&client->dev, "could not get irq of gpio %d, %d\n",
+			gpio_int, client->irq);
+		return client->irq;
+	}
+
+	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);
+
+	if (IS_ENABLED(CONFIG_COMMON_CLK))
+		hym8563_clkout_register_clk(hym8563);
+
+	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");