[4/4] RTC: rk808: add RTC driver for RK808 PMIC RTC

RK808 PMIC is a MFD with RTC as one of the device. Adding RTC driver
for supporting RTC device present inside RK808 PMIC.

Signed-off-by: Chris Zhong <zyw@rock-chips.com>
---
 drivers/rtc/Kconfig     |   11 +
 drivers/rtc/Makefile    |    1 +
 drivers/rtc/rtc-rk808.c |  564 +++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 576 insertions(+)
 create mode 100644 drivers/rtc/rtc-rk808.c

adding Mike Turquette to cc since this is also a clock driver.

Hello Chris,

Overall it looks good to me, I've just a comment about the driver structure.

On 08/17/2014 04:02 AM, Chris Zhong wrote:
> RK808 PMIC is a MFD with RTC as one of the device. Adding RTC driver
> for supporting RTC device present inside RK808 PMIC.
> 
> Signed-off-by: Chris Zhong <zyw@rock-chips.com>
> ---
>  drivers/rtc/Kconfig     |   11 +
>  drivers/rtc/Makefile    |    1 +
>  drivers/rtc/rtc-rk808.c |  564 +++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 576 insertions(+)
>  create mode 100644 drivers/rtc/rtc-rk808.c
> 
> diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
> index a168e96..48f61b2 100644
> --- a/drivers/rtc/Kconfig
> +++ b/drivers/rtc/Kconfig
> @@ -288,6 +288,17 @@ 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_RK808
> +	tristate "Rockchip RK808 RTC"
> +	depends on MFD_RK808
> +	help
> +	  If you say yes here you will get support for the
> +	  RTC of Rk808 PMIC.
> +
> +	  This driver can also be built as a module. If so, the module
> +	  will be called rtc-rk808.
> +
> +
>  config RTC_DRV_RS5C372
>  	tristate "Ricoh R2025S/D, RS5C372A/B, RV5C386, RV5C387A"
>  	help
> diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
> index 56f061c..91fe4647 100644
> --- a/drivers/rtc/Makefile
> +++ b/drivers/rtc/Makefile
> @@ -109,6 +109,7 @@ obj-$(CONFIG_RTC_DRV_PUV3)	+= rtc-puv3.o
>  obj-$(CONFIG_RTC_DRV_PXA)	+= rtc-pxa.o
>  obj-$(CONFIG_RTC_DRV_R9701)	+= rtc-r9701.o
>  obj-$(CONFIG_RTC_DRV_RC5T583)	+= rtc-rc5t583.o
> +obj-$(CONFIG_RTC_DRV_RK808)	+= rtc-rk808.o
>  obj-$(CONFIG_RTC_DRV_RP5C01)	+= rtc-rp5c01.o
>  obj-$(CONFIG_RTC_DRV_RS5C313)	+= rtc-rs5c313.o
>  obj-$(CONFIG_RTC_DRV_RS5C348)	+= rtc-rs5c348.o
> diff --git a/drivers/rtc/rtc-rk808.c b/drivers/rtc/rtc-rk808.c
> new file mode 100644
> index 0000000..0abb919
> --- /dev/null
> +++ b/drivers/rtc/rtc-rk808.c
> @@ -0,0 +1,564 @@
> +/*
> + * RTC driver for Rockchip RK808
> + *
> + * Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd
> + *
> + * Author: Chris Zhong <zyw@rock-chips.com>
> + * Author: Zhang Qing <zhangqing@rock-chips.com>
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms and conditions of the GNU General Public License,
> + * version 2, as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope 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/kernel.h>
> +#include <linux/time.h>
> +#include <linux/rtc.h>
> +#include <linux/slab.h>
> +#include <linux/bcd.h>
> +#include <linux/interrupt.h>
> +#include <linux/ioctl.h>
> +#include <linux/completion.h>
> +#include <linux/mfd/rk808.h>
> +#include <linux/delay.h>
> +#include <linux/platform_device.h>
> +#include <linux/miscdevice.h>
> +#include <linux/i2c.h>
> +#include <linux/irqdomain.h>
> +#include <linux/clk-provider.h>
> +
> +/* RTC_CTRL_REG bitfields */
> +#define BIT_RTC_CTRL_REG_STOP_RTC_M		0x01
> +#define BIT_RTC_CTRL_REG_ROUND_30S_M		0x02
> +#define BIT_RTC_CTRL_REG_AUTO_COMP_M		0x04
> +#define BIT_RTC_CTRL_REG_MODE_12_24_M		0x08
> +#define BIT_RTC_CTRL_REG_TEST_MODE_M		0x10
> +#define BIT_RTC_CTRL_REG_SET_32_COUNTER_M	0x20
> +#define BIT_RTC_CTRL_REG_GET_TIME_M		0x40
> +#define BIT_RTC_CTRL_REG_RTC_V_OPT_M		0x80
> +
> +/* RTC_STATUS_REG bitfields */
> +#define BIT_RTC_STATUS_REG_RUN_M		0x02
> +#define BIT_RTC_STATUS_REG_1S_EVENT_M		0x04
> +#define BIT_RTC_STATUS_REG_1M_EVENT_M		0x08
> +#define BIT_RTC_STATUS_REG_1H_EVENT_M		0x10
> +#define BIT_RTC_STATUS_REG_1D_EVENT_M		0x20
> +#define BIT_RTC_STATUS_REG_ALARM_M		0x40
> +#define BIT_RTC_STATUS_REG_POWER_UP_M		0x80
> +
> +/* RTC_INTERRUPTS_REG bitfields */
> +#define BIT_RTC_INTERRUPTS_REG_EVERY_M		0x03
> +#define BIT_RTC_INTERRUPTS_REG_IT_TIMER_M	0x04
> +#define BIT_RTC_INTERRUPTS_REG_IT_ALARM_M	0x08
> +
> +/* DEVCTRL bitfields */
> +#define BIT_RTC_PWDN				0x40
> +
> +/* REG_SECONDS_REG through REG_YEARS_REG is how many registers? */
> +#define ALL_TIME_REGS				7
> +#define ALL_ALM_REGS				6
> +
> +#define RTC_SET_TIME_RETRIES	5
> +#define RTC_GET_TIME_RETRIES	5
> +
> +struct rk808_rtc {
> +	struct rk808 *rk808;
> +	struct rtc_device *rtc;
> +	unsigned int alarm_enabled:1;
> +#ifdef CONFIG_COMMON_CLK
> +	struct clk_onecell_data clk_data;
> +	struct clk_hw		clkout1_hw;
> +	struct clk_hw		clkout2_hw;
> +#endif

As I mentioned on a previous review I really think these clocks should be
managed on a separate clock driver. It's not uncommon for PMIC chips to
have a bunch of regulators, a RTC and some clock ouputs and usually each
of these components have their own driver.

You are already adding a mult-function device driver for this PMIC so is
just a matter of adding another mfd cell for the clock driver.

I know that drivers/rtc/rtc-hym8563.c does the same thing and manage both
a RTC and a clock output but in this case it appears that chip is a plain
RTC chip with a clock. So I guess in that case it was not worth the
complexity of adding three drivers (mfd, rtc and clock) for just a simple
RTC? Arguably even that chip should be seen as a multi-function device
though but I'll let Mike to judge that. What I really think is that there
is a reason why we have both drivers/rtc and drivers/clk so we should try
to keep the needed support in the right place to avoid adding unnecessary
cross subsystem maintenance burden.

> +};
> +
> +/*
> + * Read current time and date in RTC
> + */
> +static int rk808_rtc_readtime(struct device *dev, struct rtc_time *tm)
> +{
> +	struct rk808_rtc *rk808_rtc = dev_get_drvdata(dev);
> +	struct rk808 *rk808 = rk808_rtc->rk808;
> +	int ret;
> +	u8 rtc_data[ALL_TIME_REGS + 1];
> +
> +	/* Has the RTC been programmed? */
> +	ret = regmap_update_bits(rk808->regmap, RK808_RTC_CTRL_REG,
> +				 BIT_RTC_CTRL_REG_RTC_V_OPT_M, 0);
> +	if (ret < 0) {
> +		dev_err(dev, "Failed to update RTC control: %d\n", ret);
> +		return ret;
> +	}
> +
> +	ret = regmap_bulk_read(rk808->regmap, RK808_SECONDS_REG, rtc_data, 6);
> +	if (ret < 0) {
> +		dev_err(dev, "Failed to bulk read rtc_data: %d\n", ret);
> +		return ret;
> +	}
> +	tm->tm_sec = bcd2bin(rtc_data[0]);
> +	tm->tm_min = bcd2bin(rtc_data[1]);
> +	tm->tm_hour = bcd2bin(rtc_data[2]);
> +	tm->tm_mday = bcd2bin(rtc_data[3]);
> +	tm->tm_mon = bcd2bin(rtc_data[4]) - 1;
> +	tm->tm_year = bcd2bin(rtc_data[5]) + 100;
> +	tm->tm_wday = bcd2bin(rtc_data[6]);
> +	dev_dbg(dev, "RTC date/time %4d-%02d-%02d(%d) %02d:%02d:%02d\n",
> +		1900 + tm->tm_year, tm->tm_mon + 1, tm->tm_mday,
> +		tm->tm_wday, tm->tm_hour , tm->tm_min, tm->tm_sec);
> +
> +	return 0;
> +}
> +
> +/*
> + * Set current time and date in RTC
> + */
> +static int rk808_rtc_set_time(struct device *dev, struct rtc_time *tm)
> +{
> +	struct rk808_rtc *rk808_rtc = dev_get_drvdata(dev);
> +	struct rk808 *rk808 = rk808_rtc->rk808;
> +	int ret;
> +	uint32_t rtc_data[ALL_TIME_REGS + 1];
> +
> +	rtc_data[0] = bin2bcd(tm->tm_sec);
> +	rtc_data[1] = bin2bcd(tm->tm_min);
> +	rtc_data[2] = bin2bcd(tm->tm_hour);
> +	rtc_data[3] = bin2bcd(tm->tm_mday);
> +	rtc_data[4] = bin2bcd(tm->tm_mon + 1);
> +	rtc_data[5] = bin2bcd(tm->tm_year - 100);
> +	rtc_data[6] = bin2bcd(tm->tm_wday);
> +	dev_dbg(dev, "set RTC date/time %4d-%02d-%02d(%d) %02d:%02d:%02d\n",
> +		1900 + tm->tm_year, tm->tm_mon + 1, tm->tm_mday,
> +		tm->tm_wday, tm->tm_hour , tm->tm_min, tm->tm_sec);
> +
> +	/* Stop RTC while updating the RTC registers */
> +	ret = regmap_update_bits(rk808->regmap, RK808_RTC_CTRL_REG,
> +				 BIT_RTC_CTRL_REG_STOP_RTC_M,
> +				 BIT_RTC_CTRL_REG_STOP_RTC_M);
> +	if (ret < 0) {
> +		dev_err(dev, "Failed to update RTC control: %d\n", ret);
> +		return ret;
> +	}
> +
> +	ret = regmap_bulk_write(rk808->regmap, RK808_SECONDS_REG, rtc_data, 6);
> +	if (ret < 0) {
> +		dev_err(dev, "Failed to bull write rtc_data: %d\n", ret);
> +		return ret;
> +	}
> +	/* Start RTC again */
> +	ret = regmap_update_bits(rk808->regmap, RK808_RTC_CTRL_REG,
> +				 BIT_RTC_CTRL_REG_STOP_RTC_M, 0);
> +	if (ret < 0) {
> +		dev_err(dev, "Failed to update RTC control: %d\n", ret);
> +		return ret;
> +	}
> +	return 0;
> +}
> +
> +/*
> + * Read alarm time and date in RTC
> + */
> +static int rk808_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
> +{
> +	struct rk808_rtc *rk808_rtc = dev_get_drvdata(dev);
> +	struct rk808 *rk808 = rk808_rtc->rk808;
> +	int ret;
> +	uint32_t int_reg;
> +	u8 alrm_data[ALL_ALM_REGS + 1];
> +
> +	ret = regmap_bulk_read(rk808->regmap,
> +			       RK808_ALARM_SECONDS_REG, alrm_data, 6);
> +
> +	/* some of these fields may be wildcard/"match all" */
> +	alrm->time.tm_sec = bcd2bin(alrm_data[0]);
> +	alrm->time.tm_min = bcd2bin(alrm_data[1]);
> +	alrm->time.tm_hour = bcd2bin(alrm_data[2]);
> +	alrm->time.tm_mday = bcd2bin(alrm_data[3]);
> +	alrm->time.tm_mon = bcd2bin(alrm_data[4]) - 1;
> +	alrm->time.tm_year = bcd2bin(alrm_data[5]) + 100;
> +
> +	ret = regmap_read(rk808->regmap, RK808_RTC_INT_REG, &int_reg);
> +	if (ret < 0) {
> +		dev_err(dev, "Failed to read RTC INT REG: %d\n", ret);
> +		return ret;
> +	}
> +
> +	dev_dbg(dev, "alrm read RTC date/time %4d-%02d-%02d(%d) %02d:%02d:%02d\n",
> +		1900 + alrm->time.tm_year, alrm->time.tm_mon + 1,
> +		alrm->time.tm_mday, alrm->time.tm_wday, alrm->time.tm_hour,
> +		alrm->time.tm_min, alrm->time.tm_sec);
> +
> +	alrm->enabled = (int_reg & BIT_RTC_INTERRUPTS_REG_IT_ALARM_M) ? 1 : 0;
> +
> +	return 0;
> +}
> +
> +static int rk808_rtc_stop_alarm(struct rk808_rtc *rk808_rtc)
> +{
> +	int ret = 0;
> +	struct rk808 *rk808 = rk808_rtc->rk808;
> +
> +	ret = regmap_update_bits(rk808->regmap, RK808_RTC_INT_REG,
> +				 BIT_RTC_INTERRUPTS_REG_IT_ALARM_M, 0);
> +	if (!ret)
> +		rk808_rtc->alarm_enabled = 0;
> +
> +	return ret;
> +}
> +
> +static int rk808_rtc_start_alarm(struct rk808_rtc *rk808_rtc)
> +{
> +	int ret = 0;
> +	struct rk808 *rk808 = rk808_rtc->rk808;
> +
> +	ret = regmap_update_bits(rk808->regmap, RK808_RTC_INT_REG,
> +				 BIT_RTC_INTERRUPTS_REG_IT_ALARM_M,
> +				 BIT_RTC_INTERRUPTS_REG_IT_ALARM_M);
> +	if (!ret)
> +		rk808_rtc->alarm_enabled = 1;
> +
> +	return ret;
> +}
> +
> +static int rk808_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
> +{
> +	struct rk808_rtc *rk808_rtc = dev_get_drvdata(dev);
> +	struct rk808 *rk808 = rk808_rtc->rk808;
> +	int ret;
> +	unsigned char alrm_data[ALL_TIME_REGS + 1];
> +
> +	ret = rk808_rtc_stop_alarm(rk808_rtc);
> +	if (ret < 0) {
> +		dev_err(dev, "Failed to stop alarm: %d\n", ret);
> +		return ret;
> +	}
> +	dev_dbg(dev, "alrm set RTC date/time %4d-%02d-%02d(%d) %02d:%02d:%02d\n",
> +		1900 + alrm->time.tm_year, alrm->time.tm_mon + 1,
> +		alrm->time.tm_mday, alrm->time.tm_wday, alrm->time.tm_hour,
> +		alrm->time.tm_min, alrm->time.tm_sec);
> +
> +	alrm_data[0] = bin2bcd(alrm->time.tm_sec);
> +	alrm_data[1] = bin2bcd(alrm->time.tm_min);
> +	alrm_data[2] = bin2bcd(alrm->time.tm_hour);
> +	alrm_data[3] = bin2bcd(alrm->time.tm_mday);
> +	alrm_data[4] = bin2bcd(alrm->time.tm_mon + 1);
> +	alrm_data[5] = bin2bcd(alrm->time.tm_year - 100);
> +
> +	ret = regmap_bulk_write(rk808->regmap,
> +				RK808_ALARM_SECONDS_REG, alrm_data, 6);
> +	if (ret < 0) {
> +		dev_err(dev, "Failed to bulk write: %d\n", ret);
> +		return ret;
> +	}
> +	if (alrm->enabled) {
> +		ret = rk808_rtc_start_alarm(rk808_rtc);
> +		if (ret < 0) {
> +			dev_err(dev, "Failed to start alarm: %d\n", ret);
> +			return ret;
> +		}
> +	}
> +	return 0;
> +}
> +
> +static int rk808_rtc_alarm_irq_enable(struct device *dev,
> +				      unsigned int enabled)
> +{
> +	struct rk808_rtc *rk808_rtc = dev_get_drvdata(dev);
> +
> +	if (enabled)
> +		return rk808_rtc_start_alarm(rk808_rtc);
> +
> +	return rk808_rtc_stop_alarm(rk808_rtc);
> +}
> +
> +/*
> + * We will just handle setting the frequency and make use the framework for
> + * reading the periodic interupts.
> + *
> + * @freq: Current periodic IRQ freq:
> + * bit 0: every second
> + * bit 1: every minute
> + * bit 2: every hour
> + * bit 3: every day
> + */
> +static irqreturn_t rk808_alm_irq(int irq, void *data)
> +{
> +	struct rk808_rtc *rk808_rtc = data;
> +	struct rk808 *rk808 = rk808_rtc->rk808;
> +	int ret;
> +	uint32_t rtc_ctl;
> +
> +	ret = regmap_update_bits(rk808->regmap, RK808_RTC_STATUS_REG,
> +				 0, 0);
> +	if (ret < 0) {
> +		dev_err(rk808_rtc->rk808->dev,
> +			"%s:Failed to update RTC status: %d\n", __func__, ret);
> +		return ret;
> +	}
> +
> +	rtc_update_irq(rk808_rtc->rtc, 1, RTC_IRQF | RTC_AF);
> +	dev_info(rk808_rtc->rk808->dev,
> +		 "%s:irq=%d,rtc_ctl=0x%x\n", __func__, irq, rtc_ctl);
> +	return IRQ_HANDLED;
> +}
> +
> +static const struct rtc_class_ops rk808_rtc_ops = {
> +	.read_time = rk808_rtc_readtime,
> +	.set_time = rk808_rtc_set_time,
> +	.read_alarm = rk808_rtc_readalarm,
> +	.set_alarm = rk808_rtc_setalarm,
> +	.alarm_irq_enable = rk808_rtc_alarm_irq_enable,
> +};
> +
> +#ifdef CONFIG_PM
> +/* Turn off the alarm if it should not be a wake source. */
> +static int rk808_rtc_suspend(struct device *dev)
> +{
> +	struct platform_device *pdev = to_platform_device(dev);
> +	struct rk808_rtc *rk808_rtc = dev_get_drvdata(&pdev->dev);
> +	int ret;
> +
> +	if (rk808_rtc->alarm_enabled && device_may_wakeup(&pdev->dev))
> +		ret = rk808_rtc_start_alarm(rk808_rtc);
> +	else
> +		ret = rk808_rtc_stop_alarm(rk808_rtc);
> +
> +	if (ret != 0)
> +		dev_err(&pdev->dev, "Failed to update RTC alarm: %d\n", ret);
> +
> +	return 0;
> +}
> +
> +/* Enable the alarm if it should be enabled (in case it was disabled to
> + * prevent use as a wake source).
> + */
> +static int rk808_rtc_resume(struct device *dev)
> +{
> +	struct platform_device *pdev = to_platform_device(dev);
> +	struct rk808_rtc *rk808_rtc = dev_get_drvdata(&pdev->dev);
> +	int ret;
> +
> +	if (rk808_rtc->alarm_enabled) {
> +		ret = rk808_rtc_start_alarm(rk808_rtc);
> +		if (ret)
> +			dev_err(&pdev->dev,
> +				"Failed to restart RTC alarm: %d\n", ret);
> +	}
> +
> +	return 0;
> +}
> +#else
> +#define rk808_rtc_suspend NULL
> +#define rk808_rtc_resume NULL
> +#endif
> +
> +static const struct dev_pm_ops rk808_rtc_pm_ops = {
> +	.suspend = rk808_rtc_suspend,
> +	.resume = rk808_rtc_resume,
> +	.poweroff = rk808_rtc_suspend,
> +};
> +
> +#ifdef CONFIG_COMMON_CLK
> +static unsigned long rk808_clkout_recalc_rate(struct clk_hw *hw,
> +					      unsigned long parent_rate)
> +{
> +	return 32768;
> +}
> +
> +static int rk808_clkout1_is_prepared(struct clk_hw *hw)
> +{
> +	return 1;
> +}
> +
> +static int rk808_clkout2_control(struct clk_hw *hw, bool enable)
> +{
> +	struct rk808_rtc *rk808_rtc = container_of(hw, struct rk808_rtc,
> +						   clkout2_hw);
> +	struct rk808 *rk808 = rk808_rtc->rk808;
> +
> +	return regmap_update_bits(rk808->regmap, RK808_CLK32OUT_REG,
> +				  CLK32KOUT2_EN, enable ? CLK32KOUT2_EN : 0);
> +}
> +
> +static int rk808_clkout2_prepare(struct clk_hw *hw)
> +{
> +	return rk808_clkout2_control(hw, 1);
> +}
> +
> +static void rk808_clkout2_unprepare(struct clk_hw *hw)
> +{
> +	rk808_clkout2_control(hw, 0);
> +}
> +
> +static int rk808_clkout2_is_prepared(struct clk_hw *hw)
> +{
> +	struct rk808_rtc *rk808_rtc = container_of(hw, struct rk808_rtc,
> +						   clkout2_hw);
> +	struct rk808 *rk808 = rk808_rtc->rk808;
> +	uint32_t val;
> +
> +	int ret = regmap_read(rk808->regmap, RK808_CLK32OUT_REG, &val);
> +
> +	if (ret < 0)
> +		return ret;
> +
> +	return (val & CLK32KOUT2_EN) ? 1 : 0;
> +}
> +
> +static const struct clk_ops rk808_clkout1_ops = {
> +	.recalc_rate = rk808_clkout_recalc_rate,
> +	.is_prepared = rk808_clkout1_is_prepared,
> +};
> +
> +static const struct clk_ops rk808_clkout2_ops = {
> +	.prepare = rk808_clkout2_prepare,
> +	.unprepare = rk808_clkout2_unprepare,
> +	.is_prepared = rk808_clkout2_is_prepared,
> +	.recalc_rate = rk808_clkout_recalc_rate,
> +};
> +
> +static int register_clocks(struct rk808_rtc *rk808_rtc)
> +{
> +	struct clk **clk_table;
> +	struct clk_init_data init;
> +	struct rk808 *rk808 = rk808_rtc->rk808;
> +	struct i2c_client *client = rk808->i2c;
> +	struct device_node *node = client->dev.of_node;
> +
> +	clk_table = devm_kzalloc(&client->dev,
> +				 2*sizeof(struct clk *), GFP_KERNEL);
> +	if (!clk_table)
> +		return -ENOMEM;
> +
> +	init.flags = CLK_IS_ROOT;
> +	init.parent_names = NULL;
> +	init.num_parents = 0;
> +	init.name = "rk808-clkout1";
> +	init.ops = &rk808_clkout1_ops;
> +	rk808_rtc->clkout1_hw.init = &init;
> +	clk_table[0] = clk_register(&client->dev, &rk808_rtc->clkout1_hw);

Maybe using devm_clk_register() instead?

> +
> +	init.name = "rk808-clkout2";
> +	init.ops = &rk808_clkout2_ops;
> +	rk808_rtc->clkout2_hw.init = &init;
> +	clk_table[1] = clk_register(&client->dev, &rk808_rtc->clkout2_hw);
> +
> +	rk808_rtc->clk_data.clks = clk_table;
> +	rk808_rtc->clk_data.clk_num = 2;
> +	of_clk_add_provider(node, of_clk_src_onecell_get, clk_table);
> +
> +	return 0;
> +}
> +#endif
> +
> +/*2012.1.1 12:00:00 Saturday*/
> +struct rtc_time tm_def = {
> +			.tm_wday = 6,
> +			.tm_year = 112,
> +			.tm_mon = 0,
> +			.tm_mday = 1,
> +			.tm_hour = 12,
> +			.tm_min = 0,
> +			.tm_sec = 0,
> +};
> +
> +static int rk808_rtc_probe(struct platform_device *pdev)
> +{
> +	struct rk808 *rk808 = dev_get_drvdata(pdev->dev.parent);
> +	struct rk808_rtc *rk808_rtc;
> +	struct rtc_time tm;
> +	int alm_irq;
> +	int ret;
> +
> +	rk808_rtc = devm_kzalloc(&pdev->dev, sizeof(*rk808_rtc), GFP_KERNEL);
> +	if (rk808_rtc == NULL)
> +		return -ENOMEM;
> +
> +	platform_set_drvdata(pdev, rk808_rtc);
> +	rk808_rtc->rk808 = rk808;
> +
> +	/* start rtc default */
> +	ret = regmap_update_bits(rk808->regmap, RK808_RTC_CTRL_REG,
> +				 BIT_RTC_CTRL_REG_STOP_RTC_M, 0);
> +	if (ret < 0) {
> +		dev_err(&pdev->dev,
> +			"Failed to read RTC control: %d\n", ret);
> +		return ret;
> +	}
> +
> +	ret = regmap_write(rk808->regmap, RK808_RTC_STATUS_REG, 0xfe);
> +	if (ret < 0) {
> +		dev_err(&pdev->dev,
> +			"Failed to write RTC control: %d\n", ret);
> +			return ret;
> +	}
> +
> +	/* set init time */
> +	ret = rk808_rtc_readtime(&pdev->dev, &tm);
> +	if (ret < 0) {
> +		dev_err(&pdev->dev, "Failed to read RTC time\n");
> +		return ret;
> +	}
> +	ret = rtc_valid_tm(&tm);
> +	if (ret) {
> +		dev_err(&pdev->dev, "invalid date/time and init time\n");
> +		rk808_rtc_set_time(&pdev->dev, &tm_def);
> +	}
> +
> +	device_init_wakeup(&pdev->dev, 1);
> +
> +	rk808_rtc->rtc = devm_rtc_device_register(&pdev->dev,
> +		"rk808", &rk808_rtc_ops, THIS_MODULE);
> +	if (IS_ERR(rk808_rtc->rtc)) {
> +		ret = PTR_ERR(rk808_rtc->rtc);
> +		return ret;
> +	}
> +
> +	alm_irq  = platform_get_irq(pdev, 0);
> +	if (alm_irq <= 0) {
> +		dev_warn(&pdev->dev, "Wake up is not possible as irq = %d\n",
> +			 alm_irq);
> +		return -ENXIO;
> +	}
> +
> +	/* request alarm irq of rk808 */
> +	ret = devm_request_threaded_irq(&pdev->dev, alm_irq, NULL,
> +					rk808_alm_irq,
> +					IRQF_TRIGGER_LOW | IRQF_EARLY_RESUME,
> +					"RTC alarm", rk808_rtc);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Failed to request alarm IRQ %d: %d\n",
> +			alm_irq, ret);
> +	}
> +	device_set_wakeup_capable(&pdev->dev, 1);
> +
> +#ifdef CONFIG_COMMON_CLK
> +	ret = register_clocks(rk808_rtc);
> +#endif
> +
> +	dev_info(rk808->dev, "%s:ok\n", __func__);
> +
> +	return ret;
> +}
> +
> +static struct platform_driver rk808_rtc_driver = {
> +	.probe = rk808_rtc_probe,
> +	.driver = {
> +		.name = "rk808-rtc",
> +		.pm = &rk808_rtc_pm_ops,
> +	},
> +};
> +
> +module_platform_driver(rk808_rtc_driver);
> +
> +MODULE_DESCRIPTION("RTC driver for the rk808 series PMICs");
> +MODULE_AUTHOR("Chris Zhong <zyw@rock-chips.com>");
> +MODULE_AUTHOR("Zhang Qing <zhanqging@rock-chips.com>");
> +MODULE_LICENSE("GPL");
> +MODULE_ALIAS("platform:rk808-rtc");
> 

Best regards,
Javier

Hi Javier,

Am Montag, 18. August 2014, 20:17:03 schrieb Javier Martinez Canillas:
> adding Mike Turquette to cc since this is also a clock driver.
> 
> Hello Chris,
> 
> Overall it looks good to me, I've just a comment about the driver structure.
> On 08/17/2014 04:02 AM, Chris Zhong wrote:
> > RK808 PMIC is a MFD with RTC as one of the device. Adding RTC driver
> > for supporting RTC device present inside RK808 PMIC.
> > 
> > Signed-off-by: Chris Zhong <zyw@rock-chips.com>
> > ---
> > 
> >  drivers/rtc/Kconfig     |   11 +
> >  drivers/rtc/Makefile    |    1 +
> >  drivers/rtc/rtc-rk808.c |  564
> >  +++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 576
> >  insertions(+)
> >  create mode 100644 drivers/rtc/rtc-rk808.c
> > 
> > diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
> > index a168e96..48f61b2 100644
> > --- a/drivers/rtc/Kconfig
> > +++ b/drivers/rtc/Kconfig
> > @@ -288,6 +288,17 @@ 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_RK808
> > +	tristate "Rockchip RK808 RTC"
> > +	depends on MFD_RK808
> > +	help
> > +	  If you say yes here you will get support for the
> > +	  RTC of Rk808 PMIC.
> > +
> > +	  This driver can also be built as a module. If so, the module
> > +	  will be called rtc-rk808.
> > +
> > +
> > 
> >  config RTC_DRV_RS5C372
> >  
> >  	tristate "Ricoh R2025S/D, RS5C372A/B, RV5C386, RV5C387A"
> >  	help
> > 
> > diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
> > index 56f061c..91fe4647 100644
> > --- a/drivers/rtc/Makefile
> > +++ b/drivers/rtc/Makefile
> > @@ -109,6 +109,7 @@ obj-$(CONFIG_RTC_DRV_PUV3)	+= rtc-puv3.o
> > 
> >  obj-$(CONFIG_RTC_DRV_PXA)	+= rtc-pxa.o
> >  obj-$(CONFIG_RTC_DRV_R9701)	+= rtc-r9701.o
> >  obj-$(CONFIG_RTC_DRV_RC5T583)	+= rtc-rc5t583.o
> > 
> > +obj-$(CONFIG_RTC_DRV_RK808)	+= rtc-rk808.o
> > 
> >  obj-$(CONFIG_RTC_DRV_RP5C01)	+= rtc-rp5c01.o
> >  obj-$(CONFIG_RTC_DRV_RS5C313)	+= rtc-rs5c313.o
> >  obj-$(CONFIG_RTC_DRV_RS5C348)	+= rtc-rs5c348.o
> > 
> > diff --git a/drivers/rtc/rtc-rk808.c b/drivers/rtc/rtc-rk808.c
> > new file mode 100644
> > index 0000000..0abb919
> > --- /dev/null
> > +++ b/drivers/rtc/rtc-rk808.c
> > @@ -0,0 +1,564 @@
> > +/*
> > + * RTC driver for Rockchip RK808
> > + *
> > + * Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd
> > + *
> > + * Author: Chris Zhong <zyw@rock-chips.com>
> > + * Author: Zhang Qing <zhangqing@rock-chips.com>
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > it
> > + * under the terms and conditions of the GNU General Public License,
> > + * version 2, as published by the Free Software Foundation.
> > + *
> > + * This program is distributed in the hope 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/kernel.h>
> > +#include <linux/time.h>
> > +#include <linux/rtc.h>
> > +#include <linux/slab.h>
> > +#include <linux/bcd.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/ioctl.h>
> > +#include <linux/completion.h>
> > +#include <linux/mfd/rk808.h>
> > +#include <linux/delay.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/miscdevice.h>
> > +#include <linux/i2c.h>
> > +#include <linux/irqdomain.h>
> > +#include <linux/clk-provider.h>
> > +
> > +/* RTC_CTRL_REG bitfields */
> > +#define BIT_RTC_CTRL_REG_STOP_RTC_M		0x01
> > +#define BIT_RTC_CTRL_REG_ROUND_30S_M		0x02
> > +#define BIT_RTC_CTRL_REG_AUTO_COMP_M		0x04
> > +#define BIT_RTC_CTRL_REG_MODE_12_24_M		0x08
> > +#define BIT_RTC_CTRL_REG_TEST_MODE_M		0x10
> > +#define BIT_RTC_CTRL_REG_SET_32_COUNTER_M	0x20
> > +#define BIT_RTC_CTRL_REG_GET_TIME_M		0x40
> > +#define BIT_RTC_CTRL_REG_RTC_V_OPT_M		0x80
> > +
> > +/* RTC_STATUS_REG bitfields */
> > +#define BIT_RTC_STATUS_REG_RUN_M		0x02
> > +#define BIT_RTC_STATUS_REG_1S_EVENT_M		0x04
> > +#define BIT_RTC_STATUS_REG_1M_EVENT_M		0x08
> > +#define BIT_RTC_STATUS_REG_1H_EVENT_M		0x10
> > +#define BIT_RTC_STATUS_REG_1D_EVENT_M		0x20
> > +#define BIT_RTC_STATUS_REG_ALARM_M		0x40
> > +#define BIT_RTC_STATUS_REG_POWER_UP_M		0x80
> > +
> > +/* RTC_INTERRUPTS_REG bitfields */
> > +#define BIT_RTC_INTERRUPTS_REG_EVERY_M		0x03
> > +#define BIT_RTC_INTERRUPTS_REG_IT_TIMER_M	0x04
> > +#define BIT_RTC_INTERRUPTS_REG_IT_ALARM_M	0x08
> > +
> > +/* DEVCTRL bitfields */
> > +#define BIT_RTC_PWDN				0x40
> > +
> > +/* REG_SECONDS_REG through REG_YEARS_REG is how many registers? */
> > +#define ALL_TIME_REGS				7
> > +#define ALL_ALM_REGS				6
> > +
> > +#define RTC_SET_TIME_RETRIES	5
> > +#define RTC_GET_TIME_RETRIES	5
> > +
> > +struct rk808_rtc {
> > +	struct rk808 *rk808;
> > +	struct rtc_device *rtc;
> > +	unsigned int alarm_enabled:1;
> > +#ifdef CONFIG_COMMON_CLK
> > +	struct clk_onecell_data clk_data;
> > +	struct clk_hw		clkout1_hw;
> > +	struct clk_hw		clkout2_hw;
> > +#endif
> 
> As I mentioned on a previous review I really think these clocks should be
> managed on a separate clock driver. It's not uncommon for PMIC chips to
> have a bunch of regulators, a RTC and some clock ouputs and usually each
> of these components have their own driver.
> 
> You are already adding a mult-function device driver for this PMIC so is
> just a matter of adding another mfd cell for the clock driver.
> 
> I know that drivers/rtc/rtc-hym8563.c does the same thing and manage both
> a RTC and a clock output but in this case it appears that chip is a plain
> RTC chip with a clock. So I guess in that case it was not worth the
> complexity of adding three drivers (mfd, rtc and clock) for just a simple
> RTC? Arguably even that chip should be seen as a multi-function device
> though but I'll let Mike to judge that. What I really think is that there
> is a reason why we have both drivers/rtc and drivers/clk so we should try
> to keep the needed support in the right place to avoid adding unnecessary
> cross subsystem maintenance burden.

Mike said in the past, that he doesn't require everything that provides a 
clock to be sitting in drivers/clk. This (and the minimal size of the clkout 
of hy8563) let me to decide to put the clkout into the rtc.

For the rk808, I guess it should either be a separate mfd-cell or part of the 
core mfd driver - but not the rtc cell.


Heiko