Patchwork [RFC,v1,6/6] drivers: rtc: Add support for Qualcomm PMIC8058 RTC

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Submitter Trilok Soni
Date Nov. 10, 2010, 12:48 p.m.
Message ID <1289393281-4459-7-git-send-email-tsoni@codeaurora.org>
Download mbox | patch
Permalink /patch/70632/
State New
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Comments

Trilok Soni - Nov. 10, 2010, 12:48 p.m.
From: Anirudh Ghayal <aghayal@codeaurora.org>

PMIC8058 is Qualcomm's power management IC. A
32-bit RTC is housed inside this PMIC. The RTC driver
uses SSBI to communicate with the RTC module.

Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Anirudh Ghayal <aghayal@codeaurora.org>
---
 drivers/rtc/Kconfig            |    9 +
 drivers/rtc/Makefile           |    1 +
 drivers/rtc/rtc-pm8058.c       |  487 ++++++++++++++++++++++++++++++++++++++++
 include/linux/rtc/rtc-pm8058.h |   29 +++
 4 files changed, 526 insertions(+), 0 deletions(-)
 create mode 100644 drivers/rtc/rtc-pm8058.c
 create mode 100644 include/linux/rtc/rtc-pm8058.h
Trilok Soni - Nov. 12, 2010, 8:53 a.m.
Hi Alessandro,

On 11/10/2010 6:18 PM, Trilok Soni wrote:
> From: Anirudh Ghayal <aghayal@codeaurora.org>
> 
> PMIC8058 is Qualcomm's power management IC. A
> 32-bit RTC is housed inside this PMIC. The RTC driver
> uses SSBI to communicate with the RTC module.
> 
> Cc: Alessandro Zummo <a.zummo@towertech.it>
> Signed-off-by: Anirudh Ghayal <aghayal@codeaurora.org>

Please review this driver. Thanks.

---Trilok Soni
Lars-Peter Clausen - Nov. 12, 2010, 12:53 p.m.
Trilok Soni wrote:
> From: Anirudh Ghayal <aghayal@codeaurora.org>
> 
> PMIC8058 is Qualcomm's power management IC. A
> 32-bit RTC is housed inside this PMIC. The RTC driver
> uses SSBI to communicate with the RTC module.
> 
> Cc: Alessandro Zummo <a.zummo@towertech.it>
> Signed-off-by: Anirudh Ghayal <aghayal@codeaurora.org>
> ---
>  drivers/rtc/Kconfig            |    9 +
>  drivers/rtc/Makefile           |    1 +
>  drivers/rtc/rtc-pm8058.c       |  487 ++++++++++++++++++++++++++++++++++++++++
>  include/linux/rtc/rtc-pm8058.h |   29 +++
>  4 files changed, 526 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/rtc/rtc-pm8058.c
>  create mode 100644 include/linux/rtc/rtc-pm8058.h
> 
> diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
> index 2883428..9f4ea00 100644
> --- a/drivers/rtc/Kconfig
> +++ b/drivers/rtc/Kconfig
> @@ -665,6 +665,15 @@ config RTC_DRV_NUC900
>  	  If you say yes here you get support for the RTC subsystem of the
>  	  NUC910/NUC920 used in embedded systems.
>  
> +config RTC_DRV_PM8058
> +	tristate "Qualcomm PMIC8058 RTC"
> +	depends on PMIC8058
> +	help
> +	  Say Y here if you want to support the Qualcomm PMIC8058 RTC.
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called pmic8058-rtc.
> +
>  comment "on-CPU RTC drivers"
>  
>  config RTC_DRV_DAVINCI
> diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
> index 4c2832d..d7a4f7d 100644
> --- a/drivers/rtc/Makefile
> +++ b/drivers/rtc/Makefile
> @@ -73,6 +73,7 @@ obj-$(CONFIG_RTC_DRV_PCF8563)	+= rtc-pcf8563.o
>  obj-$(CONFIG_RTC_DRV_PCF8583)	+= rtc-pcf8583.o
>  obj-$(CONFIG_RTC_DRV_PCF2123)	+= rtc-pcf2123.o
>  obj-$(CONFIG_RTC_DRV_PCF50633)	+= rtc-pcf50633.o
> +obj-$(CONFIG_RTC_DRV_PM8058)	+= rtc-pm8058.o
>  obj-$(CONFIG_RTC_DRV_PL030)	+= rtc-pl030.o
>  obj-$(CONFIG_RTC_DRV_PL031)	+= rtc-pl031.o
>  obj-$(CONFIG_RTC_DRV_PS3)	+= rtc-ps3.o
> diff --git a/drivers/rtc/rtc-pm8058.c b/drivers/rtc/rtc-pm8058.c
> new file mode 100644
> index 0000000..9fef82d
> --- /dev/null
> +++ b/drivers/rtc/rtc-pm8058.c
> @@ -0,0 +1,487 @@
> +/* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 and
> + * only version 2 as published by the Free Software Foundation.
> + *
> + * 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.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
> + * 02110-1301, USA.
> + */
> +
> +#define pr_fmt(fmt) "%s: " fmt, __func__
> +
> +#include <linux/module.h>
> +#include <linux/init.h>
> +#include <linux/rtc.h>
> +#include <linux/mfd/pmic8058.h>
> +#include <linux/pm.h>
> +#include <linux/slab.h>
> +#include <linux/rtc/rtc-pm8058.h>
> +
> +/* RTC control registers */
> +#define PM8058_RTC_CTRL		0x1E8
> +#define PM8058_RTC_ALARM_CTRL	0x1E9
> +#define PM8058_RTC_TEST		0x1F6
> +
> +/* RTC register bases */
> +#define PM8058_RTC_READ_BASE	0x1EE
> +#define PM8058_RTC_WRITE_BASE	0x1EA
> +#define PM8058_RTC_ALARM_BASE	0x1F2
> +
> +/* RTC_CTRL register bit fields */
> +#define PM8058_RTC_ENABLE	BIT(7)
> +#define PM8058_RTC_ALARM_ENABLE	BIT(1)

Are there other bits in the ctrl register which are not touch by this driver?
If not you could turn the read-modify-write operations changing the ctrl register
into simple writes.

> +
> +#define NUM_8_BIT_RTC_REGS	0x4
> +
> +/**
> + * struct pm8058_rtc - rtc driver internal structure
> + * @rtc0 - rtc device for this driver
> + * @rtc_irq - rtc irq number
> + * @rtc_alarm_irq - rtc alarm irq number
> + * @pm_chip - pointer to pm8058 parent structure
> + */
> +struct pm8058_rtc {
> +	struct rtc_device *rtc0;
Is there a reason for the '0'?
> +	int rtc_irq;
> +	int rtc_alarm_irq;
> +	struct pm8058_chip *pm_chip;
> +};
> +
> +static int
> +pm8058_rtc_read_bytes(struct pm8058_rtc *rtc_dd, u8 *rtc_val, int base)
> +{
> +	int i, rc;
> +
> +	/* Read the 32-bit register value, 8 bits at a time. */
> +	for (i = 0; i < NUM_8_BIT_RTC_REGS; i++) {
> +		rc = pm8058_read(rtc_dd->pm_chip, base + i, &rtc_val[i], 1);
> +		if (rc < 0) {
> +			pr_err("PM8058 read failed\n");
> +			return rc;
> +		}
> +	}
Hm, I don't know the hardware, but I would assume that
pm8058_read(rtc_dd->pm_chip, base, rtc_val, NUM_8_BIT_RTC_REGS) should work as well.
> +
> +	return 0;
> +}
> +
> +static int
> +pm8058_rtc_write_bytes(struct pm8058_rtc *rtc_dd, u8 *rtc_val, int base)
> +{
> +	int i, rc;
> +
> +	/* Write the 32-bit register value, 8 bits at a time. */
> +	for (i = 0; i < NUM_8_BIT_RTC_REGS; i++) {
> +		rc = pm8058_write(rtc_dd->pm_chip, base + i, &rtc_val[i], 1);
> +		if (rc < 0) {
> +			pr_err("PM8058 read failed\n");
> +			return rc;
> +		}
> +	}
> +
Same here
> +	return 0;
> +}
> +
> +/*
> + * Steps to write the RTC registers.
> + * 1. Disable alarm if enabled.
> + * 2. Write 0x00 to LSB.
> + * 3. Write Byte[1], Byte[2], Byte[3] then Byte[0].
> + * 4. Enable alarm if disabled in step 1.
> + */
> +static int
> +pm8058_rtc0_set_time(struct device *dev, struct rtc_time *tm)
> +{
> +	int rc;
> +	unsigned long secs = 0;
> +	u8 value[4], reg = 0, alarm_enabled = 0, ctrl_reg = 0, i;
> +	struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev);
> +
> +	rtc_tm_to_time(tm, &secs);
> +
> +	value[0] = secs & 0xFF;
> +	value[1] = (secs >> 8) & 0xFF;
> +	value[2] = (secs >> 16) & 0xFF;
> +	value[3] = (secs >> 24) & 0xFF;
> +
> +	pr_debug("Seconds value to be written to RTC = %lu\n", secs);
> +
> +	/* Disable alarm before updating RTC */
> +	rc = pm8058_read(rtc_dd->pm_chip, PM8058_RTC_CTRL, &ctrl_reg, 1);
> +	if (rc < 0) {
> +		pr_err("PM8058 read failed\n");
dev_err instead of pr_err. The other pr_err should also be replaced.
> +		return rc;
> +	}
> +
> +	if (ctrl_reg & PM8058_RTC_ALARM_ENABLE) {
> +		alarm_enabled = 1;
> +		ctrl_reg &= ~PM8058_RTC_ALARM_ENABLE;
> +		rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_CTRL,
> +							&ctrl_reg, 1);
> +		if (rc < 0) {
> +			pr_err("PM8058 write failed\n");
> +			return rc;
> +		}
> +	}
> +
> +	/* Write Byte[1], Byte[2], Byte[3], Byte[0] */
> +	reg = 0;
> +	rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_WRITE_BASE, &reg, 1);
> +	if (rc < 0) {
> +		pr_err("PM8058 write failed\n");
> +		return rc;
> +	}
> +
> +	for (i = 1; i < NUM_8_BIT_RTC_REGS; i++) {
> +		rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_WRITE_BASE + i,
> +								&value[i], 1);
> +		if (rc < 0) {
> +			pr_err("Write to RTC registers failed\n");
> +			return rc;
> +		}
> +	}
> +
> +	rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_WRITE_BASE,
> +							&value[0], 1);
> +	if (rc < 0) {
> +		pr_err("PM8058 write failed\n");
> +		return rc;
> +	}
> +
> +	if (alarm_enabled) {
> +		ctrl_reg |= PM8058_RTC_ALARM_ENABLE;
> +		rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_CTRL,
> +							&ctrl_reg, 1);
> +		if (rc < 0) {
> +			pr_err("PM8058 write failed\n");
> +			return rc;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
> +static int
> +pm8058_rtc0_read_time(struct device *dev, struct rtc_time *tm)
> +{
> +	int rc;
> +	u8 value[4], reg;
> +	unsigned long secs = 0;
> +	struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev);
> +
> +	rc = pm8058_rtc_read_bytes(rtc_dd, value, PM8058_RTC_READ_BASE);
> +	if (rc < 0) {
> +		pr_err("RTC time read failed\n");
> +		return rc;
> +	}
> +
> +	/*
> +	 * Read the LSB again and check if there has been a carry over.
> +	 * If there is, redo the read operation.
> +	 */
> +	rc = pm8058_read(rtc_dd->pm_chip, PM8058_RTC_READ_BASE, &reg, 1);
> +	if (rc < 0) {
> +		pr_err("PM8058 read failed\n");
> +		return rc;
> +	}
> +
> +	if (unlikely(reg < value[0])) {
> +		rc = pm8058_rtc_read_bytes(rtc_dd, value,
> +						PM8058_RTC_READ_BASE);
> +		if (rc < 0) {
> +			pr_err("RTC time read failed\n");
> +			return rc;
> +		}
> +	}
> +
> +	secs = value[0] | (value[1] << 8) | (value[2] << 16) | (value[3] << 24);
> +
> +	rtc_time_to_tm(secs, tm);
> +
> +	rc = rtc_valid_tm(tm);
> +	if (rc < 0) {
> +		pr_err("Invalid time read from PMIC8058\n");
> +		return rc;
> +	}
> +
> +	pr_debug("secs = %lu, h::m:s == %d::%d::%d, d/m/y = %d/%d/%d\n",
> +			secs, tm->tm_hour, tm->tm_min, tm->tm_sec,
> +			tm->tm_mday, tm->tm_mon, tm->tm_year);
> +
> +	return 0;
> +}
> +
> +static int
> +pm8058_rtc0_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
> +{
> +	int rc;
> +	u8 value[4], reg;
> +	unsigned long secs = 0;
No need to initialize secs here.
> +	struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev);
> +
> +	/* Check if a alarm is valid */
> +	rc = rtc_valid_tm(&alarm->time);
> +	if (rc < 0) {
> +		pr_err("Alarm time invalid\n");
> +		return -EINVAL;
> +	}
The upper layer will already check if alarm->time is valid, so there is no need to
check it here again.
> +
> +	rtc_tm_to_time(&alarm->time, &secs);
> +
> +	value[0] = secs & 0xFF;
> +	value[1] = (secs >> 8) & 0xFF;
> +	value[2] = (secs >> 16) & 0xFF;
> +	value[3] = (secs >> 24) & 0xFF;
> +
> +	rc = pm8058_rtc_write_bytes(rtc_dd, value, PM8058_RTC_ALARM_BASE);
> +	if (rc < 0) {
> +		pr_err("Alarm could not be set\n");
> +		return rc;
> +	}
> +
> +	rc = pm8058_read(rtc_dd->pm_chip, PM8058_RTC_CTRL, &reg, 1);
> +	if (rc < 0) {
> +		pr_err("PM8058 read failed\n");
> +		return rc;
> +	}
> +
> +	reg = (alarm->enabled) ? (reg | PM8058_RTC_ALARM_ENABLE) :
> +					(reg & ~PM8058_RTC_ALARM_ENABLE);
> +
> +	rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_CTRL, &reg, 1);
> +	if (rc < 0) {
> +		pr_err("PM8058 write failed\n");
> +		return rc;
> +	}
> +
> +	pr_debug("Alarm Set for h:r:s=%d:%d:%d, d/m/y=%d/%d/%d\n",
> +			alarm->time.tm_hour, alarm->time.tm_min,
> +			alarm->time.tm_sec, alarm->time.tm_mday,
> +			alarm->time.tm_mon, alarm->time.tm_year);
> +
> +	return 0;
> +}
> +
> +static int
> +pm8058_rtc0_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
> +{
> +	int rc;
> +	u8 value[4], reg;
> +	unsigned long secs = 0;
No need to initialize secs here.
> +	struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev);
> +
> +	/* Check if the alarm is enabled */
> +	rc = pm8058_read(rtc_dd->pm_chip, PM8058_RTC_CTRL, &reg, 1);
> +	if (rc < 0) {
> +		pr_err("PM8058 read failed\n");
> +		return rc;
> +	}
> +	alarm->enabled = !!(reg & PM8058_RTC_ALARM_ENABLE);
> +
> +	rc = pm8058_rtc_read_bytes(rtc_dd, value,
> +					PM8058_RTC_ALARM_BASE);
> +	if (rc < 0) {
> +		pr_err("RTC alarm time read failed\n");
> +		return rc;
> +	}
> +
> +	secs = value[0] | (value[1] << 8) | (value[2] << 16) | (value[3] << 24);
> +
> +	rtc_time_to_tm(secs, &alarm->time);
> +
> +	rc = rtc_valid_tm(&alarm->time);
> +	if (rc < 0) {
> +		pr_err("Invalid time read from PMIC8058\n");
> +		return rc;
> +	}
> +
> +	pr_debug("Alarm set for - h:r:s=%d:%d:%d, d/m/y=%d/%d/%d\n",
> +		alarm->time.tm_hour, alarm->time.tm_min,
> +				alarm->time.tm_sec, alarm->time.tm_mday,
> +				alarm->time.tm_mon, alarm->time.tm_year);
> +
> +	return 0;
> +}
> +
> +static struct rtc_class_ops pm8058_rtc0_ops = {
> +	.read_time	= pm8058_rtc0_read_time,
> +	.set_alarm	= pm8058_rtc0_set_alarm,
> +	.read_alarm	= pm8058_rtc0_read_alarm,

Implementig alarm_irq_enable might be a good idea

> +};
> +
> +static irqreturn_t pm8058_alarm_trigger(int irq, void *dev_id)
> +{
> +	unsigned long events = 0;
> +	struct pm8058_rtc *rtc_dd = dev_id;
> +
> +	events = RTC_IRQF | RTC_AF;
> +	rtc_update_irq(rtc_dd->rtc0, 1, events);

just rtc_update_irq(rtc_dd->rtc0, 1, RTC_IRQF | RTC_AF); should be fine

> +
> +	pr_debug("Alarm Triggered !!\n");
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static int __devinit pm8058_rtc_probe(struct platform_device *pdev)
> +{
> +	int rc;
> +	u8 reg;
> +	struct pm8058_rtc *rtc_dd;
> +	struct pm8058_chip *pm_chip;
> +	struct pm8058_rtc_pdata *pdata = pdev->dev.platform_data;
> +
> +	if (pdata == NULL) {
> +		dev_err(&pdev->dev, "Platform data absent!\n");
> +		return -ENXIO;
> +	}
It might be a good idea to assume a default for rtc_write_enable if pdata is not set.
> +
> +	pm_chip = platform_get_drvdata(pdev);
> +	if (pm_chip == NULL) {
> +		dev_err(&pdev->dev, "Invalid driver information!\n");
> +		return -ENXIO;
> +	}
> +
> +	rtc_dd = kzalloc(sizeof(*rtc_dd), GFP_KERNEL);
> +	if (rtc_dd == NULL) {
> +		dev_err(&pdev->dev, "Unable to allocate memory!\n");
> +		return -ENOMEM;
> +	}
> +
> +	rtc_dd->rtc_irq = platform_get_irq(pdev, 0);
You don't seem to use this irq.

> +	rtc_dd->rtc_alarm_irq = platform_get_irq(pdev, 1);
> +	if (!rtc_dd->rtc_alarm_irq || !rtc_dd->rtc_irq) {
> +		dev_err(&pdev->dev, "RTC / Alarm IRQ resource absent!\n");
> +		rc = -ENXIO;
> +		goto fail_rtc_enable;
> +	}
> +
> +	rtc_dd->pm_chip = pm_chip;
> +
> +	/* Check if the RTC is on, else turn it on */
> +	rc = pm8058_read(pm_chip, PM8058_RTC_CTRL, &reg, 1);
> +	if (rc < 0) {
> +		dev_err(&pdev->dev, "PM8058 read failed!\n");
> +		goto fail_rtc_enable;
> +	}
> +
> +	if (!(reg & PM8058_RTC_ENABLE)) {
> +		reg |= PM8058_RTC_ENABLE;
> +		rc = pm8058_write(pm_chip, PM8058_RTC_CTRL, &reg, 1);
> +		if (rc < 0) {
> +			dev_err(&pdev->dev, "PM8058 write failed!\n");
> +			goto fail_rtc_enable;
> +		}
> +	}
> +
> +	if (pdata->rtc_write_enable == true)
> +		pm8058_rtc0_ops.set_time = pm8058_rtc0_set_time,
> +
> +	/* Register the RTC device */
> +	rtc_dd->rtc0 = rtc_device_register("pm8058_rtc0", &pdev->dev,
> +				&pm8058_rtc0_ops, THIS_MODULE);
> +	if (IS_ERR(rtc_dd->rtc0)) {
> +		dev_err(&pdev->dev, "%s: RTC registration failed (%ld)\n",
> +					__func__, PTR_ERR(rtc_dd->rtc0));
> +		rc = PTR_ERR(rtc_dd->rtc0);
> +		goto fail_rtc_enable;
> +	}
> +
> +	platform_set_drvdata(pdev, rtc_dd);
> +
> +	/* Request the alarm IRQ */
> +	rc = request_any_context_irq(rtc_dd->rtc_alarm_irq,
> +				 pm8058_alarm_trigger, IRQF_TRIGGER_RISING,
> +				 "pm8058_rtc_alarm", rtc_dd);
> +	if (rc < 0) {
> +		dev_err(&pdev->dev, "Request IRQ failed (%d)\n", rc);
> +		goto fail_req_irq;
> +	}
> +
> +	device_init_wakeup(&pdev->dev, 1);
> +
> +	dev_dbg(&pdev->dev, "Probe success !!\n");
> +
> +	return 0;
> +
> +fail_req_irq:
> +	rtc_device_unregister(rtc_dd->rtc0);
> +fail_rtc_enable:
> +	kfree(rtc_dd);
> +	return rc;
> +}
> +
> +#ifdef CONFIG_PM
> +static int pm8058_rtc_resume(struct device *dev)
> +{
> +	struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev);
> +
> +	if (device_may_wakeup(dev))
> +		disable_irq_wake(rtc_dd->rtc_alarm_irq);
> +
> +	return 0;
> +}
> +
> +static int pm8058_rtc_suspend(struct device *dev)
> +{
> +	struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev);
> +
> +	if (device_may_wakeup(dev))
> +		enable_irq_wake(rtc_dd->rtc_alarm_irq);
> +
> +	return 0;
> +}
> +
> +static const struct dev_pm_ops pm8058_rtc_pm_ops = {
> +	.suspend = pm8058_rtc_suspend,
> +	.resume = pm8058_rtc_resume,
> +};
> +#endif
> +
> +static int __devexit pm8058_rtc_remove(struct platform_device *pdev)
> +{
> +	struct pm8058_rtc *rtc_dd = platform_get_drvdata(pdev);
> +
> +	device_init_wakeup(&pdev->dev, 0);
> +	free_irq(rtc_dd->rtc_alarm_irq, rtc_dd);
> +	rtc_device_unregister(rtc_dd->rtc0);
> +	kfree(rtc_dd);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver pm8058_rtc_driver = {
> +	.probe		= pm8058_rtc_probe,
> +	.remove		= __devexit_p(pm8058_rtc_remove),
> +	.driver	= {
> +		.name	= "pm8058-rtc",
> +		.owner	= THIS_MODULE,
> +#ifdef CONFIG_PM
> +		.pm	= &pm8058_rtc_pm_ops,
> +#endif
> +	},
> +};
> +
> +static int __init pm8058_rtc_init(void)
> +{
> +	return platform_driver_register(&pm8058_rtc_driver);
> +}
> +
> +static void __exit pm8058_rtc_exit(void)
> +{
> +	platform_driver_unregister(&pm8058_rtc_driver);
> +}
> +
> +module_init(pm8058_rtc_init);
> +module_exit(pm8058_rtc_exit);
module_{init,exit} should go right beneath the function they are referring to

> +
> +MODULE_ALIAS("platform:pm8058-rtc");
> +MODULE_DESCRIPTION("PMIC8058 RTC driver");
> +MODULE_LICENSE("GPL v2");
> +MODULE_AUTHOR(Anirudh Ghayal "<aghayal@codeaurora.org>");
> diff --git a/include/linux/rtc/rtc-pm8058.h b/include/linux/rtc/rtc-pm8058.h
> new file mode 100644
> index 0000000..51f7c0b
> --- /dev/null
> +++ b/include/linux/rtc/rtc-pm8058.h
> @@ -0,0 +1,29 @@
> +/* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 and
> + * only version 2 as published by the Free Software Foundation.
> + *
> + * 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.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
> + * 02110-1301, USA.
> + */
> +
> +#ifndef __RTC_PM8058_H__
> +#define __RTC_PM8058_H__
> +
> +/**
> + * struct pm8058_rtc_pdata - RTC driver platform data
> + * @rtc_write_enable - variable stating RTC write capability
> + */
> +struct pm8058_rtc_pdata {
> +	bool rtc_write_enable;
> +};
Is there a technical reason why changing the rtc clocks time should be disabled or is
this a policy based decision?
> +
> +#endif /* __RTC_PM8058_H__ */
Anirudh Ghayal - Nov. 12, 2010, 3:17 p.m.
Hi Peter,

> Trilok Soni wrote:
>> From: Anirudh Ghayal<aghayal@codeaurora.org>
>>
>> PMIC8058 is Qualcomm's power management IC. A
>> 32-bit RTC is housed inside this PMIC. The RTC driver
>> uses SSBI to communicate with the RTC module.
>>
>> Cc: Alessandro Zummo<a.zummo@towertech.it>
>> Signed-off-by: Anirudh Ghayal<aghayal@codeaurora.org>
>> ---
>>   drivers/rtc/Kconfig            |    9 +
>>   drivers/rtc/Makefile           |    1 +
>>   drivers/rtc/rtc-pm8058.c       |  487 ++++++++++++++++++++++++++++++++++++++++
>>   include/linux/rtc/rtc-pm8058.h |   29 +++
>>   4 files changed, 526 insertions(+), 0 deletions(-)
>>   create mode 100644 drivers/rtc/rtc-pm8058.c
>>   create mode 100644 include/linux/rtc/rtc-pm8058.h
>>
>> diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
>> index 2883428..9f4ea00 100644
>> --- a/drivers/rtc/Kconfig
>> +++ b/drivers/rtc/Kconfig
>> @@ -665,6 +665,15 @@ config RTC_DRV_NUC900
>>   	  If you say yes here you get support for the RTC subsystem of the
>>   	  NUC910/NUC920 used in embedded systems.
>>
>> +config RTC_DRV_PM8058
>> +	tristate "Qualcomm PMIC8058 RTC"
>> +	depends on PMIC8058
>> +	help
>> +	  Say Y here if you want to support the Qualcomm PMIC8058 RTC.
>> +
>> +	  To compile this driver as a module, choose M here: the
>> +	  module will be called pmic8058-rtc.
>> +
>>   comment "on-CPU RTC drivers"
>>
>>   config RTC_DRV_DAVINCI
>> diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
>> index 4c2832d..d7a4f7d 100644
>> --- a/drivers/rtc/Makefile
>> +++ b/drivers/rtc/Makefile
>> @@ -73,6 +73,7 @@ obj-$(CONFIG_RTC_DRV_PCF8563)	+= rtc-pcf8563.o
>>   obj-$(CONFIG_RTC_DRV_PCF8583)	+= rtc-pcf8583.o
>>   obj-$(CONFIG_RTC_DRV_PCF2123)	+= rtc-pcf2123.o
>>   obj-$(CONFIG_RTC_DRV_PCF50633)	+= rtc-pcf50633.o
>> +obj-$(CONFIG_RTC_DRV_PM8058)	+= rtc-pm8058.o
>>   obj-$(CONFIG_RTC_DRV_PL030)	+= rtc-pl030.o
>>   obj-$(CONFIG_RTC_DRV_PL031)	+= rtc-pl031.o
>>   obj-$(CONFIG_RTC_DRV_PS3)	+= rtc-ps3.o
>> diff --git a/drivers/rtc/rtc-pm8058.c b/drivers/rtc/rtc-pm8058.c
>> new file mode 100644
>> index 0000000..9fef82d
>> --- /dev/null
>> +++ b/drivers/rtc/rtc-pm8058.c
>> @@ -0,0 +1,487 @@
>> +/* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License version 2 and
>> + * only version 2 as published by the Free Software Foundation.
>> + *
>> + * 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.
>> + *
>> + * You should have received a copy of the GNU General Public License
>> + * along with this program; if not, write to the Free Software
>> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
>> + * 02110-1301, USA.
>> + */
>> +
>> +#define pr_fmt(fmt) "%s: " fmt, __func__
>> +
>> +#include<linux/module.h>
>> +#include<linux/init.h>
>> +#include<linux/rtc.h>
>> +#include<linux/mfd/pmic8058.h>
>> +#include<linux/pm.h>
>> +#include<linux/slab.h>
>> +#include<linux/rtc/rtc-pm8058.h>
>> +
>> +/* RTC control registers */
>> +#define PM8058_RTC_CTRL		0x1E8
>> +#define PM8058_RTC_ALARM_CTRL	0x1E9
>> +#define PM8058_RTC_TEST		0x1F6
>> +
>> +/* RTC register bases */
>> +#define PM8058_RTC_READ_BASE	0x1EE
>> +#define PM8058_RTC_WRITE_BASE	0x1EA
>> +#define PM8058_RTC_ALARM_BASE	0x1F2
>> +
>> +/* RTC_CTRL register bit fields */
>> +#define PM8058_RTC_ENABLE	BIT(7)
>> +#define PM8058_RTC_ALARM_ENABLE	BIT(1)
>
> Are there other bits in the ctrl register which are not touch by this driver?
> If not you could turn the read-modify-write operations changing the ctrl register
> into simple writes.
>

I will check this. I think this should be possible.

>> +
>> +#define NUM_8_BIT_RTC_REGS	0x4
>> +
>> +/**
>> + * struct pm8058_rtc - rtc driver internal structure
>> + * @rtc0 - rtc device for this driver
>> + * @rtc_irq - rtc irq number
>> + * @rtc_alarm_irq - rtc alarm irq number
>> + * @pm_chip - pointer to pm8058 parent structure
>> + */
>> +struct pm8058_rtc {
>> +	struct rtc_device *rtc0;
> Is there a reason for the '0'?

No specific reason for this. I will remove the '0'.

>> +	int rtc_irq;
>> +	int rtc_alarm_irq;
>> +	struct pm8058_chip *pm_chip;
>> +};
>> +
>> +static int
>> +pm8058_rtc_read_bytes(struct pm8058_rtc *rtc_dd, u8 *rtc_val, int base)
>> +{
>> +	int i, rc;
>> +
>> +	/* Read the 32-bit register value, 8 bits at a time. */
>> +	for (i = 0; i<  NUM_8_BIT_RTC_REGS; i++) {
>> +		rc = pm8058_read(rtc_dd->pm_chip, base + i,&rtc_val[i], 1);
>> +		if (rc<  0) {
>> +			pr_err("PM8058 read failed\n");
>> +			return rc;
>> +		}
>> +	}
> Hm, I don't know the hardware, but I would assume that
> pm8058_read(rtc_dd->pm_chip, base, rtc_val, NUM_8_BIT_RTC_REGS) should work as well.

I did try this earlier but the RTC register does not get updated/return 
a correct 32-bit value. It needs indivisual 8-bit SBI operations.

>> +
>> +	return 0;
>> +}
>> +
>> +static int
>> +pm8058_rtc_write_bytes(struct pm8058_rtc *rtc_dd, u8 *rtc_val, int base)
>> +{
>> +	int i, rc;
>> +
>> +	/* Write the 32-bit register value, 8 bits at a time. */
>> +	for (i = 0; i<  NUM_8_BIT_RTC_REGS; i++) {
>> +		rc = pm8058_write(rtc_dd->pm_chip, base + i,&rtc_val[i], 1);
>> +		if (rc<  0) {
>> +			pr_err("PM8058 read failed\n");
>> +			return rc;
>> +		}
>> +	}
>> +
> Same here
>> +	return 0;
>> +}
>> +
>> +/*
>> + * Steps to write the RTC registers.
>> + * 1. Disable alarm if enabled.
>> + * 2. Write 0x00 to LSB.
>> + * 3. Write Byte[1], Byte[2], Byte[3] then Byte[0].
>> + * 4. Enable alarm if disabled in step 1.
>> + */
>> +static int
>> +pm8058_rtc0_set_time(struct device *dev, struct rtc_time *tm)
>> +{
>> +	int rc;
>> +	unsigned long secs = 0;
>> +	u8 value[4], reg = 0, alarm_enabled = 0, ctrl_reg = 0, i;
>> +	struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev);
>> +
>> +	rtc_tm_to_time(tm,&secs);
>> +
>> +	value[0] = secs&  0xFF;
>> +	value[1] = (secs>>  8)&  0xFF;
>> +	value[2] = (secs>>  16)&  0xFF;
>> +	value[3] = (secs>>  24)&  0xFF;
>> +
>> +	pr_debug("Seconds value to be written to RTC = %lu\n", secs);
>> +
>> +	/* Disable alarm before updating RTC */
>> +	rc = pm8058_read(rtc_dd->pm_chip, PM8058_RTC_CTRL,&ctrl_reg, 1);
>> +	if (rc<  0) {
>> +		pr_err("PM8058 read failed\n");
> dev_err instead of pr_err. The other pr_err should also be replaced.

Ok

>> +		return rc;
>> +	}
>> +
>> +	if (ctrl_reg&  PM8058_RTC_ALARM_ENABLE) {
>> +		alarm_enabled = 1;
>> +		ctrl_reg&= ~PM8058_RTC_ALARM_ENABLE;
>> +		rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_CTRL,
>> +							&ctrl_reg, 1);
>> +		if (rc<  0) {
>> +			pr_err("PM8058 write failed\n");
>> +			return rc;
>> +		}
>> +	}
>> +
>> +	/* Write Byte[1], Byte[2], Byte[3], Byte[0] */
>> +	reg = 0;
>> +	rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_WRITE_BASE,&reg, 1);
>> +	if (rc<  0) {
>> +		pr_err("PM8058 write failed\n");
>> +		return rc;
>> +	}
>> +
>> +	for (i = 1; i<  NUM_8_BIT_RTC_REGS; i++) {
>> +		rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_WRITE_BASE + i,
>> +								&value[i], 1);
>> +		if (rc<  0) {
>> +			pr_err("Write to RTC registers failed\n");
>> +			return rc;
>> +		}
>> +	}
>> +
>> +	rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_WRITE_BASE,
>> +							&value[0], 1);
>> +	if (rc<  0) {
>> +		pr_err("PM8058 write failed\n");
>> +		return rc;
>> +	}
>> +
>> +	if (alarm_enabled) {
>> +		ctrl_reg |= PM8058_RTC_ALARM_ENABLE;
>> +		rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_CTRL,
>> +							&ctrl_reg, 1);
>> +		if (rc<  0) {
>> +			pr_err("PM8058 write failed\n");
>> +			return rc;
>> +		}
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int
>> +pm8058_rtc0_read_time(struct device *dev, struct rtc_time *tm)
>> +{
>> +	int rc;
>> +	u8 value[4], reg;
>> +	unsigned long secs = 0;
>> +	struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev);
>> +
>> +	rc = pm8058_rtc_read_bytes(rtc_dd, value, PM8058_RTC_READ_BASE);
>> +	if (rc<  0) {
>> +		pr_err("RTC time read failed\n");
>> +		return rc;
>> +	}
>> +
>> +	/*
>> +	 * Read the LSB again and check if there has been a carry over.
>> +	 * If there is, redo the read operation.
>> +	 */
>> +	rc = pm8058_read(rtc_dd->pm_chip, PM8058_RTC_READ_BASE,&reg, 1);
>> +	if (rc<  0) {
>> +		pr_err("PM8058 read failed\n");
>> +		return rc;
>> +	}
>> +
>> +	if (unlikely(reg<  value[0])) {
>> +		rc = pm8058_rtc_read_bytes(rtc_dd, value,
>> +						PM8058_RTC_READ_BASE);
>> +		if (rc<  0) {
>> +			pr_err("RTC time read failed\n");
>> +			return rc;
>> +		}
>> +	}
>> +
>> +	secs = value[0] | (value[1]<<  8) | (value[2]<<  16) | (value[3]<<  24);
>> +
>> +	rtc_time_to_tm(secs, tm);
>> +
>> +	rc = rtc_valid_tm(tm);
>> +	if (rc<  0) {
>> +		pr_err("Invalid time read from PMIC8058\n");
>> +		return rc;
>> +	}
>> +
>> +	pr_debug("secs = %lu, h::m:s == %d::%d::%d, d/m/y = %d/%d/%d\n",
>> +			secs, tm->tm_hour, tm->tm_min, tm->tm_sec,
>> +			tm->tm_mday, tm->tm_mon, tm->tm_year);
>> +
>> +	return 0;
>> +}
>> +
>> +static int
>> +pm8058_rtc0_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
>> +{
>> +	int rc;
>> +	u8 value[4], reg;
>> +	unsigned long secs = 0;
> No need to initialize secs here.

Ok

>> +	struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev);
>> +
>> +	/* Check if a alarm is valid */
>> +	rc = rtc_valid_tm(&alarm->time);
>> +	if (rc<  0) {
>> +		pr_err("Alarm time invalid\n");
>> +		return -EINVAL;
>> +	}
> The upper layer will already check if alarm->time is valid, so there is no need to
> check it here again.

I see. I will remove this.

>> +
>> +	rtc_tm_to_time(&alarm->time,&secs);
>> +
>> +	value[0] = secs&  0xFF;
>> +	value[1] = (secs>>  8)&  0xFF;
>> +	value[2] = (secs>>  16)&  0xFF;
>> +	value[3] = (secs>>  24)&  0xFF;
>> +
>> +	rc = pm8058_rtc_write_bytes(rtc_dd, value, PM8058_RTC_ALARM_BASE);
>> +	if (rc<  0) {
>> +		pr_err("Alarm could not be set\n");
>> +		return rc;
>> +	}
>> +
>> +	rc = pm8058_read(rtc_dd->pm_chip, PM8058_RTC_CTRL,&reg, 1);
>> +	if (rc<  0) {
>> +		pr_err("PM8058 read failed\n");
>> +		return rc;
>> +	}
>> +
>> +	reg = (alarm->enabled) ? (reg | PM8058_RTC_ALARM_ENABLE) :
>> +					(reg&  ~PM8058_RTC_ALARM_ENABLE);
>> +
>> +	rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_CTRL,&reg, 1);
>> +	if (rc<  0) {
>> +		pr_err("PM8058 write failed\n");
>> +		return rc;
>> +	}
>> +
>> +	pr_debug("Alarm Set for h:r:s=%d:%d:%d, d/m/y=%d/%d/%d\n",
>> +			alarm->time.tm_hour, alarm->time.tm_min,
>> +			alarm->time.tm_sec, alarm->time.tm_mday,
>> +			alarm->time.tm_mon, alarm->time.tm_year);
>> +
>> +	return 0;
>> +}
>> +
>> +static int
>> +pm8058_rtc0_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
>> +{
>> +	int rc;
>> +	u8 value[4], reg;
>> +	unsigned long secs = 0;
> No need to initialize secs here.

Ok

>> +	struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev);
>> +
>> +	/* Check if the alarm is enabled */
>> +	rc = pm8058_read(rtc_dd->pm_chip, PM8058_RTC_CTRL,&reg, 1);
>> +	if (rc<  0) {
>> +		pr_err("PM8058 read failed\n");
>> +		return rc;
>> +	}
>> +	alarm->enabled = !!(reg&  PM8058_RTC_ALARM_ENABLE);
>> +
>> +	rc = pm8058_rtc_read_bytes(rtc_dd, value,
>> +					PM8058_RTC_ALARM_BASE);
>> +	if (rc<  0) {
>> +		pr_err("RTC alarm time read failed\n");
>> +		return rc;
>> +	}
>> +
>> +	secs = value[0] | (value[1]<<  8) | (value[2]<<  16) | (value[3]<<  24);
>> +
>> +	rtc_time_to_tm(secs,&alarm->time);
>> +
>> +	rc = rtc_valid_tm(&alarm->time);
>> +	if (rc<  0) {
>> +		pr_err("Invalid time read from PMIC8058\n");
>> +		return rc;
>> +	}
>> +
>> +	pr_debug("Alarm set for - h:r:s=%d:%d:%d, d/m/y=%d/%d/%d\n",
>> +		alarm->time.tm_hour, alarm->time.tm_min,
>> +				alarm->time.tm_sec, alarm->time.tm_mday,
>> +				alarm->time.tm_mon, alarm->time.tm_year);
>> +
>> +	return 0;
>> +}
>> +
>> +static struct rtc_class_ops pm8058_rtc0_ops = {
>> +	.read_time	= pm8058_rtc0_read_time,
>> +	.set_alarm	= pm8058_rtc0_set_alarm,
>> +	.read_alarm	= pm8058_rtc0_read_alarm,
>
> Implementig alarm_irq_enable might be a good idea

Ok, I'll try to add the other supported ops as well.

>
>> +};
>> +
>> +static irqreturn_t pm8058_alarm_trigger(int irq, void *dev_id)
>> +{
>> +	unsigned long events = 0;
>> +	struct pm8058_rtc *rtc_dd = dev_id;
>> +
>> +	events = RTC_IRQF | RTC_AF;
>> +	rtc_update_irq(rtc_dd->rtc0, 1, events);
>
> just rtc_update_irq(rtc_dd->rtc0, 1, RTC_IRQF | RTC_AF); should be fine

Ok

>
>> +
>> +	pr_debug("Alarm Triggered !!\n");
>> +
>> +	return IRQ_HANDLED;
>> +}
>> +
>> +static int __devinit pm8058_rtc_probe(struct platform_device *pdev)
>> +{
>> +	int rc;
>> +	u8 reg;
>> +	struct pm8058_rtc *rtc_dd;
>> +	struct pm8058_chip *pm_chip;
>> +	struct pm8058_rtc_pdata *pdata = pdev->dev.platform_data;
>> +
>> +	if (pdata == NULL) {
>> +		dev_err(&pdev->dev, "Platform data absent!\n");
>> +		return -ENXIO;
>> +	}
> It might be a good idea to assume a default for rtc_write_enable if pdata is not set.

Yes, makes sense.

>> +
>> +	pm_chip = platform_get_drvdata(pdev);
>> +	if (pm_chip == NULL) {
>> +		dev_err(&pdev->dev, "Invalid driver information!\n");
>> +		return -ENXIO;
>> +	}
>> +
>> +	rtc_dd = kzalloc(sizeof(*rtc_dd), GFP_KERNEL);
>> +	if (rtc_dd == NULL) {
>> +		dev_err(&pdev->dev, "Unable to allocate memory!\n");
>> +		return -ENOMEM;
>> +	}
>> +
>> +	rtc_dd->rtc_irq = platform_get_irq(pdev, 0);
> You don't seem to use this irq.

This was for the RTC tick interrupt. I will remove this code.

>
>> +	rtc_dd->rtc_alarm_irq = platform_get_irq(pdev, 1);
>> +	if (!rtc_dd->rtc_alarm_irq || !rtc_dd->rtc_irq) {
>> +		dev_err(&pdev->dev, "RTC / Alarm IRQ resource absent!\n");
>> +		rc = -ENXIO;
>> +		goto fail_rtc_enable;
>> +	}
>> +
>> +	rtc_dd->pm_chip = pm_chip;
>> +
>> +	/* Check if the RTC is on, else turn it on */
>> +	rc = pm8058_read(pm_chip, PM8058_RTC_CTRL,&reg, 1);
>> +	if (rc<  0) {
>> +		dev_err(&pdev->dev, "PM8058 read failed!\n");
>> +		goto fail_rtc_enable;
>> +	}
>> +
>> +	if (!(reg&  PM8058_RTC_ENABLE)) {
>> +		reg |= PM8058_RTC_ENABLE;
>> +		rc = pm8058_write(pm_chip, PM8058_RTC_CTRL,&reg, 1);
>> +		if (rc<  0) {
>> +			dev_err(&pdev->dev, "PM8058 write failed!\n");
>> +			goto fail_rtc_enable;
>> +		}
>> +	}
>> +
>> +	if (pdata->rtc_write_enable == true)
>> +		pm8058_rtc0_ops.set_time = pm8058_rtc0_set_time,
>> +
>> +	/* Register the RTC device */
>> +	rtc_dd->rtc0 = rtc_device_register("pm8058_rtc0",&pdev->dev,
>> +				&pm8058_rtc0_ops, THIS_MODULE);
>> +	if (IS_ERR(rtc_dd->rtc0)) {
>> +		dev_err(&pdev->dev, "%s: RTC registration failed (%ld)\n",
>> +					__func__, PTR_ERR(rtc_dd->rtc0));
>> +		rc = PTR_ERR(rtc_dd->rtc0);
>> +		goto fail_rtc_enable;
>> +	}
>> +
>> +	platform_set_drvdata(pdev, rtc_dd);
>> +
>> +	/* Request the alarm IRQ */
>> +	rc = request_any_context_irq(rtc_dd->rtc_alarm_irq,
>> +				 pm8058_alarm_trigger, IRQF_TRIGGER_RISING,
>> +				 "pm8058_rtc_alarm", rtc_dd);
>> +	if (rc<  0) {
>> +		dev_err(&pdev->dev, "Request IRQ failed (%d)\n", rc);
>> +		goto fail_req_irq;
>> +	}
>> +
>> +	device_init_wakeup(&pdev->dev, 1);
>> +
>> +	dev_dbg(&pdev->dev, "Probe success !!\n");
>> +
>> +	return 0;
>> +
>> +fail_req_irq:
>> +	rtc_device_unregister(rtc_dd->rtc0);
>> +fail_rtc_enable:
>> +	kfree(rtc_dd);
>> +	return rc;
>> +}
>> +
>> +#ifdef CONFIG_PM
>> +static int pm8058_rtc_resume(struct device *dev)
>> +{
>> +	struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev);
>> +
>> +	if (device_may_wakeup(dev))
>> +		disable_irq_wake(rtc_dd->rtc_alarm_irq);
>> +
>> +	return 0;
>> +}
>> +
>> +static int pm8058_rtc_suspend(struct device *dev)
>> +{
>> +	struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev);
>> +
>> +	if (device_may_wakeup(dev))
>> +		enable_irq_wake(rtc_dd->rtc_alarm_irq);
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct dev_pm_ops pm8058_rtc_pm_ops = {
>> +	.suspend = pm8058_rtc_suspend,
>> +	.resume = pm8058_rtc_resume,
>> +};
>> +#endif
>> +
>> +static int __devexit pm8058_rtc_remove(struct platform_device *pdev)
>> +{
>> +	struct pm8058_rtc *rtc_dd = platform_get_drvdata(pdev);
>> +
>> +	device_init_wakeup(&pdev->dev, 0);
>> +	free_irq(rtc_dd->rtc_alarm_irq, rtc_dd);
>> +	rtc_device_unregister(rtc_dd->rtc0);
>> +	kfree(rtc_dd);
>> +
>> +	return 0;
>> +}
>> +
>> +static struct platform_driver pm8058_rtc_driver = {
>> +	.probe		= pm8058_rtc_probe,
>> +	.remove		= __devexit_p(pm8058_rtc_remove),
>> +	.driver	= {
>> +		.name	= "pm8058-rtc",
>> +		.owner	= THIS_MODULE,
>> +#ifdef CONFIG_PM
>> +		.pm	=&pm8058_rtc_pm_ops,
>> +#endif
>> +	},
>> +};
>> +
>> +static int __init pm8058_rtc_init(void)
>> +{
>> +	return platform_driver_register(&pm8058_rtc_driver);
>> +}
>> +
>> +static void __exit pm8058_rtc_exit(void)
>> +{
>> +	platform_driver_unregister(&pm8058_rtc_driver);
>> +}
>> +
>> +module_init(pm8058_rtc_init);
>> +module_exit(pm8058_rtc_exit);
> module_{init,exit} should go right beneath the function they are referring to

Ok.

>
>> +
>> +MODULE_ALIAS("platform:pm8058-rtc");
>> +MODULE_DESCRIPTION("PMIC8058 RTC driver");
>> +MODULE_LICENSE("GPL v2");
>> +MODULE_AUTHOR(Anirudh Ghayal "<aghayal@codeaurora.org>");
>> diff --git a/include/linux/rtc/rtc-pm8058.h b/include/linux/rtc/rtc-pm8058.h
>> new file mode 100644
>> index 0000000..51f7c0b
>> --- /dev/null
>> +++ b/include/linux/rtc/rtc-pm8058.h
>> @@ -0,0 +1,29 @@
>> +/* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License version 2 and
>> + * only version 2 as published by the Free Software Foundation.
>> + *
>> + * 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.
>> + *
>> + * You should have received a copy of the GNU General Public License
>> + * along with this program; if not, write to the Free Software
>> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
>> + * 02110-1301, USA.
>> + */
>> +
>> +#ifndef __RTC_PM8058_H__
>> +#define __RTC_PM8058_H__
>> +
>> +/**
>> + * struct pm8058_rtc_pdata - RTC driver platform data
>> + * @rtc_write_enable - variable stating RTC write capability
>> + */
>> +struct pm8058_rtc_pdata {
>> +	bool rtc_write_enable;
>> +};
> Is there a technical reason why changing the rtc clocks time should be disabled or is
> this a policy based decision?

In some of our MSM/QSD designs, we have a single RTC shared by multiple 
processors (other than the ones running Linux). Thus, the need to have a 
non-writable RTC using this pdata.

>> +
>> +#endif /* __RTC_PM8058_H__ */
>

Thank you for the detailed review. I will make these changes in my next 
patch.

--Anirudh

Patch

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 2883428..9f4ea00 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -665,6 +665,15 @@  config RTC_DRV_NUC900
 	  If you say yes here you get support for the RTC subsystem of the
 	  NUC910/NUC920 used in embedded systems.
 
+config RTC_DRV_PM8058
+	tristate "Qualcomm PMIC8058 RTC"
+	depends on PMIC8058
+	help
+	  Say Y here if you want to support the Qualcomm PMIC8058 RTC.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called pmic8058-rtc.
+
 comment "on-CPU RTC drivers"
 
 config RTC_DRV_DAVINCI
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 4c2832d..d7a4f7d 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -73,6 +73,7 @@  obj-$(CONFIG_RTC_DRV_PCF8563)	+= rtc-pcf8563.o
 obj-$(CONFIG_RTC_DRV_PCF8583)	+= rtc-pcf8583.o
 obj-$(CONFIG_RTC_DRV_PCF2123)	+= rtc-pcf2123.o
 obj-$(CONFIG_RTC_DRV_PCF50633)	+= rtc-pcf50633.o
+obj-$(CONFIG_RTC_DRV_PM8058)	+= rtc-pm8058.o
 obj-$(CONFIG_RTC_DRV_PL030)	+= rtc-pl030.o
 obj-$(CONFIG_RTC_DRV_PL031)	+= rtc-pl031.o
 obj-$(CONFIG_RTC_DRV_PS3)	+= rtc-ps3.o
diff --git a/drivers/rtc/rtc-pm8058.c b/drivers/rtc/rtc-pm8058.c
new file mode 100644
index 0000000..9fef82d
--- /dev/null
+++ b/drivers/rtc/rtc-pm8058.c
@@ -0,0 +1,487 @@ 
+/* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+#define pr_fmt(fmt) "%s: " fmt, __func__
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/rtc.h>
+#include <linux/mfd/pmic8058.h>
+#include <linux/pm.h>
+#include <linux/slab.h>
+#include <linux/rtc/rtc-pm8058.h>
+
+/* RTC control registers */
+#define PM8058_RTC_CTRL		0x1E8
+#define PM8058_RTC_ALARM_CTRL	0x1E9
+#define PM8058_RTC_TEST		0x1F6
+
+/* RTC register bases */
+#define PM8058_RTC_READ_BASE	0x1EE
+#define PM8058_RTC_WRITE_BASE	0x1EA
+#define PM8058_RTC_ALARM_BASE	0x1F2
+
+/* RTC_CTRL register bit fields */
+#define PM8058_RTC_ENABLE	BIT(7)
+#define PM8058_RTC_ALARM_ENABLE	BIT(1)
+
+#define NUM_8_BIT_RTC_REGS	0x4
+
+/**
+ * struct pm8058_rtc - rtc driver internal structure
+ * @rtc0 - rtc device for this driver
+ * @rtc_irq - rtc irq number
+ * @rtc_alarm_irq - rtc alarm irq number
+ * @pm_chip - pointer to pm8058 parent structure
+ */
+struct pm8058_rtc {
+	struct rtc_device *rtc0;
+	int rtc_irq;
+	int rtc_alarm_irq;
+	struct pm8058_chip *pm_chip;
+};
+
+static int
+pm8058_rtc_read_bytes(struct pm8058_rtc *rtc_dd, u8 *rtc_val, int base)
+{
+	int i, rc;
+
+	/* Read the 32-bit register value, 8 bits at a time. */
+	for (i = 0; i < NUM_8_BIT_RTC_REGS; i++) {
+		rc = pm8058_read(rtc_dd->pm_chip, base + i, &rtc_val[i], 1);
+		if (rc < 0) {
+			pr_err("PM8058 read failed\n");
+			return rc;
+		}
+	}
+
+	return 0;
+}
+
+static int
+pm8058_rtc_write_bytes(struct pm8058_rtc *rtc_dd, u8 *rtc_val, int base)
+{
+	int i, rc;
+
+	/* Write the 32-bit register value, 8 bits at a time. */
+	for (i = 0; i < NUM_8_BIT_RTC_REGS; i++) {
+		rc = pm8058_write(rtc_dd->pm_chip, base + i, &rtc_val[i], 1);
+		if (rc < 0) {
+			pr_err("PM8058 read failed\n");
+			return rc;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * Steps to write the RTC registers.
+ * 1. Disable alarm if enabled.
+ * 2. Write 0x00 to LSB.
+ * 3. Write Byte[1], Byte[2], Byte[3] then Byte[0].
+ * 4. Enable alarm if disabled in step 1.
+ */
+static int
+pm8058_rtc0_set_time(struct device *dev, struct rtc_time *tm)
+{
+	int rc;
+	unsigned long secs = 0;
+	u8 value[4], reg = 0, alarm_enabled = 0, ctrl_reg = 0, i;
+	struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev);
+
+	rtc_tm_to_time(tm, &secs);
+
+	value[0] = secs & 0xFF;
+	value[1] = (secs >> 8) & 0xFF;
+	value[2] = (secs >> 16) & 0xFF;
+	value[3] = (secs >> 24) & 0xFF;
+
+	pr_debug("Seconds value to be written to RTC = %lu\n", secs);
+
+	/* Disable alarm before updating RTC */
+	rc = pm8058_read(rtc_dd->pm_chip, PM8058_RTC_CTRL, &ctrl_reg, 1);
+	if (rc < 0) {
+		pr_err("PM8058 read failed\n");
+		return rc;
+	}
+
+	if (ctrl_reg & PM8058_RTC_ALARM_ENABLE) {
+		alarm_enabled = 1;
+		ctrl_reg &= ~PM8058_RTC_ALARM_ENABLE;
+		rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_CTRL,
+							&ctrl_reg, 1);
+		if (rc < 0) {
+			pr_err("PM8058 write failed\n");
+			return rc;
+		}
+	}
+
+	/* Write Byte[1], Byte[2], Byte[3], Byte[0] */
+	reg = 0;
+	rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_WRITE_BASE, &reg, 1);
+	if (rc < 0) {
+		pr_err("PM8058 write failed\n");
+		return rc;
+	}
+
+	for (i = 1; i < NUM_8_BIT_RTC_REGS; i++) {
+		rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_WRITE_BASE + i,
+								&value[i], 1);
+		if (rc < 0) {
+			pr_err("Write to RTC registers failed\n");
+			return rc;
+		}
+	}
+
+	rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_WRITE_BASE,
+							&value[0], 1);
+	if (rc < 0) {
+		pr_err("PM8058 write failed\n");
+		return rc;
+	}
+
+	if (alarm_enabled) {
+		ctrl_reg |= PM8058_RTC_ALARM_ENABLE;
+		rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_CTRL,
+							&ctrl_reg, 1);
+		if (rc < 0) {
+			pr_err("PM8058 write failed\n");
+			return rc;
+		}
+	}
+
+	return 0;
+}
+
+static int
+pm8058_rtc0_read_time(struct device *dev, struct rtc_time *tm)
+{
+	int rc;
+	u8 value[4], reg;
+	unsigned long secs = 0;
+	struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev);
+
+	rc = pm8058_rtc_read_bytes(rtc_dd, value, PM8058_RTC_READ_BASE);
+	if (rc < 0) {
+		pr_err("RTC time read failed\n");
+		return rc;
+	}
+
+	/*
+	 * Read the LSB again and check if there has been a carry over.
+	 * If there is, redo the read operation.
+	 */
+	rc = pm8058_read(rtc_dd->pm_chip, PM8058_RTC_READ_BASE, &reg, 1);
+	if (rc < 0) {
+		pr_err("PM8058 read failed\n");
+		return rc;
+	}
+
+	if (unlikely(reg < value[0])) {
+		rc = pm8058_rtc_read_bytes(rtc_dd, value,
+						PM8058_RTC_READ_BASE);
+		if (rc < 0) {
+			pr_err("RTC time read failed\n");
+			return rc;
+		}
+	}
+
+	secs = value[0] | (value[1] << 8) | (value[2] << 16) | (value[3] << 24);
+
+	rtc_time_to_tm(secs, tm);
+
+	rc = rtc_valid_tm(tm);
+	if (rc < 0) {
+		pr_err("Invalid time read from PMIC8058\n");
+		return rc;
+	}
+
+	pr_debug("secs = %lu, h::m:s == %d::%d::%d, d/m/y = %d/%d/%d\n",
+			secs, tm->tm_hour, tm->tm_min, tm->tm_sec,
+			tm->tm_mday, tm->tm_mon, tm->tm_year);
+
+	return 0;
+}
+
+static int
+pm8058_rtc0_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+	int rc;
+	u8 value[4], reg;
+	unsigned long secs = 0;
+	struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev);
+
+	/* Check if a alarm is valid */
+	rc = rtc_valid_tm(&alarm->time);
+	if (rc < 0) {
+		pr_err("Alarm time invalid\n");
+		return -EINVAL;
+	}
+
+	rtc_tm_to_time(&alarm->time, &secs);
+
+	value[0] = secs & 0xFF;
+	value[1] = (secs >> 8) & 0xFF;
+	value[2] = (secs >> 16) & 0xFF;
+	value[3] = (secs >> 24) & 0xFF;
+
+	rc = pm8058_rtc_write_bytes(rtc_dd, value, PM8058_RTC_ALARM_BASE);
+	if (rc < 0) {
+		pr_err("Alarm could not be set\n");
+		return rc;
+	}
+
+	rc = pm8058_read(rtc_dd->pm_chip, PM8058_RTC_CTRL, &reg, 1);
+	if (rc < 0) {
+		pr_err("PM8058 read failed\n");
+		return rc;
+	}
+
+	reg = (alarm->enabled) ? (reg | PM8058_RTC_ALARM_ENABLE) :
+					(reg & ~PM8058_RTC_ALARM_ENABLE);
+
+	rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_CTRL, &reg, 1);
+	if (rc < 0) {
+		pr_err("PM8058 write failed\n");
+		return rc;
+	}
+
+	pr_debug("Alarm Set for h:r:s=%d:%d:%d, d/m/y=%d/%d/%d\n",
+			alarm->time.tm_hour, alarm->time.tm_min,
+			alarm->time.tm_sec, alarm->time.tm_mday,
+			alarm->time.tm_mon, alarm->time.tm_year);
+
+	return 0;
+}
+
+static int
+pm8058_rtc0_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+	int rc;
+	u8 value[4], reg;
+	unsigned long secs = 0;
+	struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev);
+
+	/* Check if the alarm is enabled */
+	rc = pm8058_read(rtc_dd->pm_chip, PM8058_RTC_CTRL, &reg, 1);
+	if (rc < 0) {
+		pr_err("PM8058 read failed\n");
+		return rc;
+	}
+	alarm->enabled = !!(reg & PM8058_RTC_ALARM_ENABLE);
+
+	rc = pm8058_rtc_read_bytes(rtc_dd, value,
+					PM8058_RTC_ALARM_BASE);
+	if (rc < 0) {
+		pr_err("RTC alarm time read failed\n");
+		return rc;
+	}
+
+	secs = value[0] | (value[1] << 8) | (value[2] << 16) | (value[3] << 24);
+
+	rtc_time_to_tm(secs, &alarm->time);
+
+	rc = rtc_valid_tm(&alarm->time);
+	if (rc < 0) {
+		pr_err("Invalid time read from PMIC8058\n");
+		return rc;
+	}
+
+	pr_debug("Alarm set for - h:r:s=%d:%d:%d, d/m/y=%d/%d/%d\n",
+		alarm->time.tm_hour, alarm->time.tm_min,
+				alarm->time.tm_sec, alarm->time.tm_mday,
+				alarm->time.tm_mon, alarm->time.tm_year);
+
+	return 0;
+}
+
+static struct rtc_class_ops pm8058_rtc0_ops = {
+	.read_time	= pm8058_rtc0_read_time,
+	.set_alarm	= pm8058_rtc0_set_alarm,
+	.read_alarm	= pm8058_rtc0_read_alarm,
+};
+
+static irqreturn_t pm8058_alarm_trigger(int irq, void *dev_id)
+{
+	unsigned long events = 0;
+	struct pm8058_rtc *rtc_dd = dev_id;
+
+	events = RTC_IRQF | RTC_AF;
+	rtc_update_irq(rtc_dd->rtc0, 1, events);
+
+	pr_debug("Alarm Triggered !!\n");
+
+	return IRQ_HANDLED;
+}
+
+static int __devinit pm8058_rtc_probe(struct platform_device *pdev)
+{
+	int rc;
+	u8 reg;
+	struct pm8058_rtc *rtc_dd;
+	struct pm8058_chip *pm_chip;
+	struct pm8058_rtc_pdata *pdata = pdev->dev.platform_data;
+
+	if (pdata == NULL) {
+		dev_err(&pdev->dev, "Platform data absent!\n");
+		return -ENXIO;
+	}
+
+	pm_chip = platform_get_drvdata(pdev);
+	if (pm_chip == NULL) {
+		dev_err(&pdev->dev, "Invalid driver information!\n");
+		return -ENXIO;
+	}
+
+	rtc_dd = kzalloc(sizeof(*rtc_dd), GFP_KERNEL);
+	if (rtc_dd == NULL) {
+		dev_err(&pdev->dev, "Unable to allocate memory!\n");
+		return -ENOMEM;
+	}
+
+	rtc_dd->rtc_irq = platform_get_irq(pdev, 0);
+	rtc_dd->rtc_alarm_irq = platform_get_irq(pdev, 1);
+	if (!rtc_dd->rtc_alarm_irq || !rtc_dd->rtc_irq) {
+		dev_err(&pdev->dev, "RTC / Alarm IRQ resource absent!\n");
+		rc = -ENXIO;
+		goto fail_rtc_enable;
+	}
+
+	rtc_dd->pm_chip = pm_chip;
+
+	/* Check if the RTC is on, else turn it on */
+	rc = pm8058_read(pm_chip, PM8058_RTC_CTRL, &reg, 1);
+	if (rc < 0) {
+		dev_err(&pdev->dev, "PM8058 read failed!\n");
+		goto fail_rtc_enable;
+	}
+
+	if (!(reg & PM8058_RTC_ENABLE)) {
+		reg |= PM8058_RTC_ENABLE;
+		rc = pm8058_write(pm_chip, PM8058_RTC_CTRL, &reg, 1);
+		if (rc < 0) {
+			dev_err(&pdev->dev, "PM8058 write failed!\n");
+			goto fail_rtc_enable;
+		}
+	}
+
+	if (pdata->rtc_write_enable == true)
+		pm8058_rtc0_ops.set_time = pm8058_rtc0_set_time,
+
+	/* Register the RTC device */
+	rtc_dd->rtc0 = rtc_device_register("pm8058_rtc0", &pdev->dev,
+				&pm8058_rtc0_ops, THIS_MODULE);
+	if (IS_ERR(rtc_dd->rtc0)) {
+		dev_err(&pdev->dev, "%s: RTC registration failed (%ld)\n",
+					__func__, PTR_ERR(rtc_dd->rtc0));
+		rc = PTR_ERR(rtc_dd->rtc0);
+		goto fail_rtc_enable;
+	}
+
+	platform_set_drvdata(pdev, rtc_dd);
+
+	/* Request the alarm IRQ */
+	rc = request_any_context_irq(rtc_dd->rtc_alarm_irq,
+				 pm8058_alarm_trigger, IRQF_TRIGGER_RISING,
+				 "pm8058_rtc_alarm", rtc_dd);
+	if (rc < 0) {
+		dev_err(&pdev->dev, "Request IRQ failed (%d)\n", rc);
+		goto fail_req_irq;
+	}
+
+	device_init_wakeup(&pdev->dev, 1);
+
+	dev_dbg(&pdev->dev, "Probe success !!\n");
+
+	return 0;
+
+fail_req_irq:
+	rtc_device_unregister(rtc_dd->rtc0);
+fail_rtc_enable:
+	kfree(rtc_dd);
+	return rc;
+}
+
+#ifdef CONFIG_PM
+static int pm8058_rtc_resume(struct device *dev)
+{
+	struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev);
+
+	if (device_may_wakeup(dev))
+		disable_irq_wake(rtc_dd->rtc_alarm_irq);
+
+	return 0;
+}
+
+static int pm8058_rtc_suspend(struct device *dev)
+{
+	struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev);
+
+	if (device_may_wakeup(dev))
+		enable_irq_wake(rtc_dd->rtc_alarm_irq);
+
+	return 0;
+}
+
+static const struct dev_pm_ops pm8058_rtc_pm_ops = {
+	.suspend = pm8058_rtc_suspend,
+	.resume = pm8058_rtc_resume,
+};
+#endif
+
+static int __devexit pm8058_rtc_remove(struct platform_device *pdev)
+{
+	struct pm8058_rtc *rtc_dd = platform_get_drvdata(pdev);
+
+	device_init_wakeup(&pdev->dev, 0);
+	free_irq(rtc_dd->rtc_alarm_irq, rtc_dd);
+	rtc_device_unregister(rtc_dd->rtc0);
+	kfree(rtc_dd);
+
+	return 0;
+}
+
+static struct platform_driver pm8058_rtc_driver = {
+	.probe		= pm8058_rtc_probe,
+	.remove		= __devexit_p(pm8058_rtc_remove),
+	.driver	= {
+		.name	= "pm8058-rtc",
+		.owner	= THIS_MODULE,
+#ifdef CONFIG_PM
+		.pm	= &pm8058_rtc_pm_ops,
+#endif
+	},
+};
+
+static int __init pm8058_rtc_init(void)
+{
+	return platform_driver_register(&pm8058_rtc_driver);
+}
+
+static void __exit pm8058_rtc_exit(void)
+{
+	platform_driver_unregister(&pm8058_rtc_driver);
+}
+
+module_init(pm8058_rtc_init);
+module_exit(pm8058_rtc_exit);
+
+MODULE_ALIAS("platform:pm8058-rtc");
+MODULE_DESCRIPTION("PMIC8058 RTC driver");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR(Anirudh Ghayal "<aghayal@codeaurora.org>");
diff --git a/include/linux/rtc/rtc-pm8058.h b/include/linux/rtc/rtc-pm8058.h
new file mode 100644
index 0000000..51f7c0b
--- /dev/null
+++ b/include/linux/rtc/rtc-pm8058.h
@@ -0,0 +1,29 @@ 
+/* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+#ifndef __RTC_PM8058_H__
+#define __RTC_PM8058_H__
+
+/**
+ * struct pm8058_rtc_pdata - RTC driver platform data
+ * @rtc_write_enable - variable stating RTC write capability
+ */
+struct pm8058_rtc_pdata {
+	bool rtc_write_enable;
+};
+
+#endif /* __RTC_PM8058_H__ */