| Message ID | 1404505467-26526-24-git-send-email-javier.martinez@collabora.co.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On pi?, 2014-07-04 at 22:24 +0200, Javier Martinez Canillas wrote: > The MAX7802 PMIC has a Real-Time-Clock (RTC) with two alarms. > This patch adds support for the RTC and is based on a driver > added by Simon Glass to the Chrome OS kernel 3.8 tree. > > Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk> > --- > > Changes since v6: > - Remove unused code for SMPL and WTSR. Suggested by Krzysztof Kozlowski. > - Don't spam the kernel log with unimportant info and just print for debug. > Suggested by Krzysztof Kozlowski. > - Use ARRAY_SIZE() instead of constant value. Suggested by Krzysztof Kozlowski. > - Remove duplicated register setup. Suggested by Krzysztof Kozlowski. > - Don't free/unregister managed allocated resources. > Suggested by Krzysztof Kozlowski. > --- > drivers/rtc/Kconfig | 10 + > drivers/rtc/Makefile | 1 + > drivers/rtc/rtc-max77802.c | 508 +++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 519 insertions(+) > create mode 100644 drivers/rtc/rtc-max77802.c Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Best regards, Krzysztof > > diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig > index a672dd1..243ac72 100644 > --- a/drivers/rtc/Kconfig > +++ b/drivers/rtc/Kconfig > @@ -288,6 +288,16 @@ 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_MAX77802 > + tristate "Maxim 77802 RTC" > + depends on MFD_MAX77686 > + help > + If you say yes here you will get support for the > + RTC of Maxim MAX77802 PMIC. > + > + This driver can also be built as a module. If so, the module > + will be called rtc-max77802. > + > config RTC_DRV_RS5C372 > tristate "Ricoh R2025S/D, RS5C372A/B, RV5C386, RV5C387A" > help > diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile > index 70347d0..247de78 100644 > --- a/drivers/rtc/Makefile > +++ b/drivers/rtc/Makefile > @@ -81,6 +81,7 @@ obj-$(CONFIG_RTC_DRV_MAX8998) += rtc-max8998.o > obj-$(CONFIG_RTC_DRV_MAX8997) += rtc-max8997.o > obj-$(CONFIG_RTC_DRV_MAX6902) += rtc-max6902.o > obj-$(CONFIG_RTC_DRV_MAX77686) += rtc-max77686.o > +obj-$(CONFIG_RTC_DRV_MAX77802) += rtc-max77802.o > obj-$(CONFIG_RTC_DRV_MC13XXX) += rtc-mc13xxx.o > obj-$(CONFIG_RTC_DRV_MCP795) += rtc-mcp795.o > obj-$(CONFIG_RTC_DRV_MSM6242) += rtc-msm6242.o > diff --git a/drivers/rtc/rtc-max77802.c b/drivers/rtc/rtc-max77802.c > new file mode 100644 > index 0000000..f8898ff > --- /dev/null > +++ b/drivers/rtc/rtc-max77802.c > @@ -0,0 +1,508 @@ > +/* > + * RTC driver for Maxim MAX77802 > + * > + * Copyright (C) 2013 Google, Inc > + * > + * Copyright (C) 2012 Samsung Electronics Co.Ltd > + * > + * based on rtc-max8997.c > + * > + * This program is free software; you can redistribute it and/or modify it > + * under the terms of the GNU General Public License as published by the > + * Free Software Foundation; either version 2 of the License, or (at your > + * option) any later version. > + * > + */ > + > +#include <linux/slab.h> > +#include <linux/rtc.h> > +#include <linux/delay.h> > +#include <linux/mutex.h> > +#include <linux/module.h> > +#include <linux/platform_device.h> > +#include <linux/mfd/max77686-private.h> > +#include <linux/irqdomain.h> > +#include <linux/regmap.h> > + > +/* RTC Control Register */ > +#define BCD_EN_SHIFT 0 > +#define BCD_EN_MASK (1 << BCD_EN_SHIFT) > +#define MODEL24_SHIFT 1 > +#define MODEL24_MASK (1 << MODEL24_SHIFT) > +/* RTC Update Register1 */ > +#define RTC_UDR_SHIFT 0 > +#define RTC_UDR_MASK (1 << RTC_UDR_SHIFT) > +#define RTC_RBUDR_SHIFT 4 > +#define RTC_RBUDR_MASK (1 << RTC_RBUDR_SHIFT) > +/* RTC Hour register */ > +#define HOUR_PM_SHIFT 6 > +#define HOUR_PM_MASK (1 << HOUR_PM_SHIFT) > +/* RTC Alarm Enable */ > +#define ALARM_ENABLE_SHIFT 7 > +#define ALARM_ENABLE_MASK (1 << ALARM_ENABLE_SHIFT) > + > +/* For the RTCAE1 register, we write this value to enable the alarm */ > +#define ALARM_ENABLE_VALUE 0x77 > + > +#define MAX77802_RTC_UPDATE_DELAY_US 200 > + > +enum { > + RTC_SEC = 0, > + RTC_MIN, > + RTC_HOUR, > + RTC_WEEKDAY, > + RTC_MONTH, > + RTC_YEAR, > + RTC_DATE, > + RTC_NR_TIME > +}; > + > +struct max77802_rtc_info { > + struct device *dev; > + struct max77686_dev *max77802; > + struct i2c_client *rtc; > + struct rtc_device *rtc_dev; > + struct mutex lock; > + > + struct regmap *regmap; > + > + int virq; > + int rtc_24hr_mode; > +}; > + > +enum MAX77802_RTC_OP { > + MAX77802_RTC_WRITE, > + MAX77802_RTC_READ, > +}; > + > +static inline int max77802_rtc_calculate_wday(u8 shifted) > +{ > + int counter = -1; > + > + while (shifted) { > + shifted >>= 1; > + counter++; > + } > + > + return counter; > +} > + > +static void max77802_rtc_data_to_tm(u8 *data, struct rtc_time *tm, > + int rtc_24hr_mode) > +{ > + tm->tm_sec = data[RTC_SEC] & 0xff; > + tm->tm_min = data[RTC_MIN] & 0xff; > + if (rtc_24hr_mode) > + tm->tm_hour = data[RTC_HOUR] & 0x1f; > + else { > + tm->tm_hour = data[RTC_HOUR] & 0x0f; > + if (data[RTC_HOUR] & HOUR_PM_MASK) > + tm->tm_hour += 12; > + } > + > + tm->tm_wday = max77802_rtc_calculate_wday(data[RTC_WEEKDAY] & 0xff); > + tm->tm_mday = data[RTC_DATE] & 0x1f; > + tm->tm_mon = (data[RTC_MONTH] & 0x0f) - 1; > + > + tm->tm_year = data[RTC_YEAR] & 0xff; > + tm->tm_yday = 0; > + tm->tm_isdst = 0; > +} > + > +static int max77802_rtc_tm_to_data(struct rtc_time *tm, u8 *data) > +{ > + data[RTC_SEC] = tm->tm_sec; > + data[RTC_MIN] = tm->tm_min; > + data[RTC_HOUR] = tm->tm_hour; > + data[RTC_WEEKDAY] = 1 << tm->tm_wday; > + data[RTC_DATE] = tm->tm_mday; > + data[RTC_MONTH] = tm->tm_mon + 1; > + data[RTC_YEAR] = tm->tm_year; > + > + return 0; > +} > + > +static int max77802_rtc_update(struct max77802_rtc_info *info, > + enum MAX77802_RTC_OP op) > +{ > + int ret; > + unsigned int data; > + > + if (op == MAX77802_RTC_WRITE) > + data = 1 << RTC_UDR_SHIFT; > + else > + data = 1 << RTC_RBUDR_SHIFT; > + > + ret = regmap_update_bits(info->max77802->regmap, > + MAX77802_RTC_UPDATE0, data, data); > + if (ret < 0) > + dev_err(info->dev, "%s: fail to write update reg(ret=%d, data=0x%x)\n", > + __func__, ret, data); > + else { > + /* Minimum delay required before RTC update. */ > + usleep_range(MAX77802_RTC_UPDATE_DELAY_US, > + MAX77802_RTC_UPDATE_DELAY_US * 2); > + } > + > + return ret; > +} > + > +static int max77802_rtc_read_time(struct device *dev, struct rtc_time *tm) > +{ > + struct max77802_rtc_info *info = dev_get_drvdata(dev); > + u8 data[RTC_NR_TIME]; > + int ret; > + > + mutex_lock(&info->lock); > + > + ret = max77802_rtc_update(info, MAX77802_RTC_READ); > + if (ret < 0) > + goto out; > + > + ret = regmap_bulk_read(info->max77802->regmap, > + MAX77802_RTC_SEC, data, RTC_NR_TIME); > + if (ret < 0) { > + dev_err(info->dev, "%s: fail to read time reg(%d)\n", __func__, > + ret); > + goto out; > + } > + > + max77802_rtc_data_to_tm(data, tm, info->rtc_24hr_mode); > + > + ret = rtc_valid_tm(tm); > + > +out: > + mutex_unlock(&info->lock); > + return ret; > +} > + > +static int max77802_rtc_set_time(struct device *dev, struct rtc_time *tm) > +{ > + struct max77802_rtc_info *info = dev_get_drvdata(dev); > + u8 data[RTC_NR_TIME]; > + int ret; > + > + ret = max77802_rtc_tm_to_data(tm, data); > + if (ret < 0) > + return ret; > + > + mutex_lock(&info->lock); > + > + ret = regmap_bulk_write(info->max77802->regmap, > + MAX77802_RTC_SEC, data, RTC_NR_TIME); > + if (ret < 0) { > + dev_err(info->dev, "%s: fail to write time reg(%d)\n", __func__, > + ret); > + goto out; > + } > + > + ret = max77802_rtc_update(info, MAX77802_RTC_WRITE); > + > +out: > + mutex_unlock(&info->lock); > + return ret; > +} > + > +static int max77802_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) > +{ > + struct max77802_rtc_info *info = dev_get_drvdata(dev); > + u8 data[RTC_NR_TIME]; > + unsigned int val; > + int ret; > + > + mutex_lock(&info->lock); > + > + ret = max77802_rtc_update(info, MAX77802_RTC_READ); > + if (ret < 0) > + goto out; > + > + ret = regmap_bulk_read(info->max77802->regmap, > + MAX77802_ALARM1_SEC, data, RTC_NR_TIME); > + if (ret < 0) { > + dev_err(info->dev, "%s:%d fail to read alarm reg(%d)\n", > + __func__, __LINE__, ret); > + goto out; > + } > + > + max77802_rtc_data_to_tm(data, &alrm->time, info->rtc_24hr_mode); > + > + alrm->enabled = 0; > + ret = regmap_read(info->max77802->regmap, > + MAX77802_RTC_AE1, &val); > + if (ret < 0) { > + dev_err(info->dev, "%s:%d fail to read alarm enable(%d)\n", > + __func__, __LINE__, ret); > + goto out; > + } > + if (val) > + alrm->enabled = 1; > + > + alrm->pending = 0; > + ret = regmap_read(info->max77802->regmap, MAX77802_REG_STATUS2, &val); > + if (ret < 0) { > + dev_err(info->dev, "%s:%d fail to read status2 reg(%d)\n", > + __func__, __LINE__, ret); > + goto out; > + } > + > + if (val & (1 << 2)) /* RTCA1 */ > + alrm->pending = 1; > + > +out: > + mutex_unlock(&info->lock); > + return 0; > +} > + > +static int max77802_rtc_stop_alarm(struct max77802_rtc_info *info) > +{ > + int ret; > + > + if (!mutex_is_locked(&info->lock)) > + dev_warn(info->dev, "%s: should have mutex locked\n", __func__); > + > + ret = max77802_rtc_update(info, MAX77802_RTC_READ); > + if (ret < 0) > + goto out; > + > + ret = regmap_write(info->max77802->regmap, > + MAX77802_RTC_AE1, 0); > + if (ret < 0) { > + dev_err(info->dev, "%s: fail to write alarm reg(%d)\n", > + __func__, ret); > + goto out; > + } > + > + ret = max77802_rtc_update(info, MAX77802_RTC_WRITE); > +out: > + return ret; > +} > + > +static int max77802_rtc_start_alarm(struct max77802_rtc_info *info) > +{ > + int ret; > + > + if (!mutex_is_locked(&info->lock)) > + dev_warn(info->dev, "%s: should have mutex locked\n", > + __func__); > + > + ret = max77802_rtc_update(info, MAX77802_RTC_READ); > + if (ret < 0) > + goto out; > + > + ret = regmap_write(info->max77802->regmap, > + MAX77802_RTC_AE1, > + ALARM_ENABLE_VALUE); > + > + if (ret < 0) { > + dev_err(info->dev, "%s: fail to read alarm reg(%d)\n", > + __func__, ret); > + goto out; > + } > + > + ret = max77802_rtc_update(info, MAX77802_RTC_WRITE); > +out: > + return ret; > +} > + > +static int max77802_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) > +{ > + struct max77802_rtc_info *info = dev_get_drvdata(dev); > + u8 data[RTC_NR_TIME]; > + int ret; > + > + ret = max77802_rtc_tm_to_data(&alrm->time, data); > + if (ret < 0) > + return ret; > + > + mutex_lock(&info->lock); > + > + ret = max77802_rtc_stop_alarm(info); > + if (ret < 0) > + goto out; > + > + ret = regmap_bulk_write(info->max77802->regmap, > + MAX77802_ALARM1_SEC, data, RTC_NR_TIME); > + > + if (ret < 0) { > + dev_err(info->dev, "%s: fail to write alarm reg(%d)\n", > + __func__, ret); > + goto out; > + } > + > + ret = max77802_rtc_update(info, MAX77802_RTC_WRITE); > + if (ret < 0) > + goto out; > + > + if (alrm->enabled) > + ret = max77802_rtc_start_alarm(info); > +out: > + mutex_unlock(&info->lock); > + return ret; > +} > + > +static int max77802_rtc_alarm_irq_enable(struct device *dev, > + unsigned int enabled) > +{ > + struct max77802_rtc_info *info = dev_get_drvdata(dev); > + int ret; > + > + mutex_lock(&info->lock); > + if (enabled) > + ret = max77802_rtc_start_alarm(info); > + else > + ret = max77802_rtc_stop_alarm(info); > + mutex_unlock(&info->lock); > + > + return ret; > +} > + > +static irqreturn_t max77802_rtc_alarm_irq(int irq, void *data) > +{ > + struct max77802_rtc_info *info = data; > + > + dev_dbg(info->dev, "%s:irq(%d)\n", __func__, irq); > + > + rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF); > + > + return IRQ_HANDLED; > +} > + > +static const struct rtc_class_ops max77802_rtc_ops = { > + .read_time = max77802_rtc_read_time, > + .set_time = max77802_rtc_set_time, > + .read_alarm = max77802_rtc_read_alarm, > + .set_alarm = max77802_rtc_set_alarm, > + .alarm_irq_enable = max77802_rtc_alarm_irq_enable, > +}; > + > +static int max77802_rtc_init_reg(struct max77802_rtc_info *info) > +{ > + u8 data[2]; > + int ret; > + > + max77802_rtc_update(info, MAX77802_RTC_READ); > + > + /* Set RTC control register : Binary mode, 24hour mdoe */ > + data[0] = (1 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT); > + data[1] = (0 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT); > + > + info->rtc_24hr_mode = 1; > + > + ret = regmap_bulk_write(info->max77802->regmap, > + MAX77802_RTC_CONTROLM, data, ARRAY_SIZE(data)); > + if (ret < 0) { > + dev_err(info->dev, "%s: fail to write controlm reg(%d)\n", > + __func__, ret); > + return ret; > + } > + > + ret = max77802_rtc_update(info, MAX77802_RTC_WRITE); > + return ret; > +} > + > +static int max77802_rtc_probe(struct platform_device *pdev) > +{ > + struct max77686_dev *max77802 = dev_get_drvdata(pdev->dev.parent); > + struct max77802_rtc_info *info; > + int ret; > + > + dev_dbg(&pdev->dev, "%s\n", __func__); > + > + info = devm_kzalloc(&pdev->dev, sizeof(struct max77802_rtc_info), > + GFP_KERNEL); > + if (!info) > + return -ENOMEM; > + > + mutex_init(&info->lock); > + info->dev = &pdev->dev; > + info->max77802 = max77802; > + info->rtc = max77802->i2c; > + > + platform_set_drvdata(pdev, info); > + > + ret = max77802_rtc_init_reg(info); > + > + if (ret < 0) { > + dev_err(&pdev->dev, "Failed to initialize RTC reg:%d\n", ret); > + return ret; > + } > + > + device_init_wakeup(&pdev->dev, 1); > + > + info->rtc_dev = devm_rtc_device_register(&pdev->dev, "max77802-rtc", > + &max77802_rtc_ops, THIS_MODULE); > + > + if (IS_ERR(info->rtc_dev)) { > + ret = PTR_ERR(info->rtc_dev); > + dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret); > + if (ret == 0) > + ret = -EINVAL; > + return ret; > + } > + info->virq = regmap_irq_get_virq(max77802->rtc_irq_data, > + MAX77686_RTCIRQ_RTCA1); > + > + if (info->virq <= 0) { > + dev_err(&pdev->dev, "Failed to get virtual IRQ %d\n", > + MAX77686_RTCIRQ_RTCA1); > + ret = -EINVAL; > + return ret; > + } > + > + ret = devm_request_threaded_irq(&pdev->dev, info->virq, NULL, > + max77802_rtc_alarm_irq, 0, "rtc-alarm1", > + info); > + if (ret < 0) > + dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n", > + info->virq, ret); > + > + return ret; > +} > + > +#ifdef CONFIG_PM_SLEEP > +static int max77802_rtc_suspend(struct device *dev) > +{ > + if (device_may_wakeup(dev)) { > + struct max77802_rtc_info *info = dev_get_drvdata(dev); > + > + return enable_irq_wake(info->virq); > + } > + > + return 0; > +} > + > +static int max77802_rtc_resume(struct device *dev) > +{ > + if (device_may_wakeup(dev)) { > + struct max77802_rtc_info *info = dev_get_drvdata(dev); > + > + return disable_irq_wake(info->virq); > + } > + > + return 0; > +} > +#endif > + > +static SIMPLE_DEV_PM_OPS(max77802_rtc_pm_ops, > + max77802_rtc_suspend, max77802_rtc_resume); > + > +static const struct platform_device_id rtc_id[] = { > + { "max77802-rtc", 0 }, > + {}, > +}; > + > +static struct platform_driver max77802_rtc_driver = { > + .driver = { > + .name = "max77802-rtc", > + .owner = THIS_MODULE, > + .pm = &max77802_rtc_pm_ops, > + }, > + .probe = max77802_rtc_probe, > + .id_table = rtc_id, > +}; > + > +module_platform_driver(max77802_rtc_driver); > + > +MODULE_DESCRIPTION("Maxim MAX77802 RTC driver"); > +MODULE_AUTHOR("Simon Glass <sjg@chromium.org>"); > +MODULE_LICENSE("GPL");
Hello Krzysztof, On 07/07/2014 08:06 AM, Krzysztof Kozlowski wrote: > On pi?, 2014-07-04 at 22:24 +0200, Javier Martinez Canillas wrote: >> The MAX7802 PMIC has a Real-Time-Clock (RTC) with two alarms. >> This patch adds support for the RTC and is based on a driver >> added by Simon Glass to the Chrome OS kernel 3.8 tree. >> >> Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk> >> --- >> >> Changes since v6: >> - Remove unused code for SMPL and WTSR. Suggested by Krzysztof Kozlowski. >> - Don't spam the kernel log with unimportant info and just print for debug. >> Suggested by Krzysztof Kozlowski. >> - Use ARRAY_SIZE() instead of constant value. Suggested by Krzysztof Kozlowski. >> - Remove duplicated register setup. Suggested by Krzysztof Kozlowski. >> - Don't free/unregister managed allocated resources. >> Suggested by Krzysztof Kozlowski. >> --- >> drivers/rtc/Kconfig | 10 + >> drivers/rtc/Makefile | 1 + >> drivers/rtc/rtc-max77802.c | 508 +++++++++++++++++++++++++++++++++++++++++++++ >> 3 files changed, 519 insertions(+) >> create mode 100644 drivers/rtc/rtc-max77802.c > > > Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> > Thanks a lot for the review and for all the feedback you gave me on each version of the series. > Best regards, > Krzysztof > > Best regards, Javier
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index a672dd1..243ac72 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -288,6 +288,16 @@ 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_MAX77802 + tristate "Maxim 77802 RTC" + depends on MFD_MAX77686 + help + If you say yes here you will get support for the + RTC of Maxim MAX77802 PMIC. + + This driver can also be built as a module. If so, the module + will be called rtc-max77802. + config RTC_DRV_RS5C372 tristate "Ricoh R2025S/D, RS5C372A/B, RV5C386, RV5C387A" help diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index 70347d0..247de78 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -81,6 +81,7 @@ obj-$(CONFIG_RTC_DRV_MAX8998) += rtc-max8998.o obj-$(CONFIG_RTC_DRV_MAX8997) += rtc-max8997.o obj-$(CONFIG_RTC_DRV_MAX6902) += rtc-max6902.o obj-$(CONFIG_RTC_DRV_MAX77686) += rtc-max77686.o +obj-$(CONFIG_RTC_DRV_MAX77802) += rtc-max77802.o obj-$(CONFIG_RTC_DRV_MC13XXX) += rtc-mc13xxx.o obj-$(CONFIG_RTC_DRV_MCP795) += rtc-mcp795.o obj-$(CONFIG_RTC_DRV_MSM6242) += rtc-msm6242.o diff --git a/drivers/rtc/rtc-max77802.c b/drivers/rtc/rtc-max77802.c new file mode 100644 index 0000000..f8898ff --- /dev/null +++ b/drivers/rtc/rtc-max77802.c @@ -0,0 +1,508 @@ +/* + * RTC driver for Maxim MAX77802 + * + * Copyright (C) 2013 Google, Inc + * + * Copyright (C) 2012 Samsung Electronics Co.Ltd + * + * based on rtc-max8997.c + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + * + */ + +#include <linux/slab.h> +#include <linux/rtc.h> +#include <linux/delay.h> +#include <linux/mutex.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/mfd/max77686-private.h> +#include <linux/irqdomain.h> +#include <linux/regmap.h> + +/* RTC Control Register */ +#define BCD_EN_SHIFT 0 +#define BCD_EN_MASK (1 << BCD_EN_SHIFT) +#define MODEL24_SHIFT 1 +#define MODEL24_MASK (1 << MODEL24_SHIFT) +/* RTC Update Register1 */ +#define RTC_UDR_SHIFT 0 +#define RTC_UDR_MASK (1 << RTC_UDR_SHIFT) +#define RTC_RBUDR_SHIFT 4 +#define RTC_RBUDR_MASK (1 << RTC_RBUDR_SHIFT) +/* RTC Hour register */ +#define HOUR_PM_SHIFT 6 +#define HOUR_PM_MASK (1 << HOUR_PM_SHIFT) +/* RTC Alarm Enable */ +#define ALARM_ENABLE_SHIFT 7 +#define ALARM_ENABLE_MASK (1 << ALARM_ENABLE_SHIFT) + +/* For the RTCAE1 register, we write this value to enable the alarm */ +#define ALARM_ENABLE_VALUE 0x77 + +#define MAX77802_RTC_UPDATE_DELAY_US 200 + +enum { + RTC_SEC = 0, + RTC_MIN, + RTC_HOUR, + RTC_WEEKDAY, + RTC_MONTH, + RTC_YEAR, + RTC_DATE, + RTC_NR_TIME +}; + +struct max77802_rtc_info { + struct device *dev; + struct max77686_dev *max77802; + struct i2c_client *rtc; + struct rtc_device *rtc_dev; + struct mutex lock; + + struct regmap *regmap; + + int virq; + int rtc_24hr_mode; +}; + +enum MAX77802_RTC_OP { + MAX77802_RTC_WRITE, + MAX77802_RTC_READ, +}; + +static inline int max77802_rtc_calculate_wday(u8 shifted) +{ + int counter = -1; + + while (shifted) { + shifted >>= 1; + counter++; + } + + return counter; +} + +static void max77802_rtc_data_to_tm(u8 *data, struct rtc_time *tm, + int rtc_24hr_mode) +{ + tm->tm_sec = data[RTC_SEC] & 0xff; + tm->tm_min = data[RTC_MIN] & 0xff; + if (rtc_24hr_mode) + tm->tm_hour = data[RTC_HOUR] & 0x1f; + else { + tm->tm_hour = data[RTC_HOUR] & 0x0f; + if (data[RTC_HOUR] & HOUR_PM_MASK) + tm->tm_hour += 12; + } + + tm->tm_wday = max77802_rtc_calculate_wday(data[RTC_WEEKDAY] & 0xff); + tm->tm_mday = data[RTC_DATE] & 0x1f; + tm->tm_mon = (data[RTC_MONTH] & 0x0f) - 1; + + tm->tm_year = data[RTC_YEAR] & 0xff; + tm->tm_yday = 0; + tm->tm_isdst = 0; +} + +static int max77802_rtc_tm_to_data(struct rtc_time *tm, u8 *data) +{ + data[RTC_SEC] = tm->tm_sec; + data[RTC_MIN] = tm->tm_min; + data[RTC_HOUR] = tm->tm_hour; + data[RTC_WEEKDAY] = 1 << tm->tm_wday; + data[RTC_DATE] = tm->tm_mday; + data[RTC_MONTH] = tm->tm_mon + 1; + data[RTC_YEAR] = tm->tm_year; + + return 0; +} + +static int max77802_rtc_update(struct max77802_rtc_info *info, + enum MAX77802_RTC_OP op) +{ + int ret; + unsigned int data; + + if (op == MAX77802_RTC_WRITE) + data = 1 << RTC_UDR_SHIFT; + else + data = 1 << RTC_RBUDR_SHIFT; + + ret = regmap_update_bits(info->max77802->regmap, + MAX77802_RTC_UPDATE0, data, data); + if (ret < 0) + dev_err(info->dev, "%s: fail to write update reg(ret=%d, data=0x%x)\n", + __func__, ret, data); + else { + /* Minimum delay required before RTC update. */ + usleep_range(MAX77802_RTC_UPDATE_DELAY_US, + MAX77802_RTC_UPDATE_DELAY_US * 2); + } + + return ret; +} + +static int max77802_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + struct max77802_rtc_info *info = dev_get_drvdata(dev); + u8 data[RTC_NR_TIME]; + int ret; + + mutex_lock(&info->lock); + + ret = max77802_rtc_update(info, MAX77802_RTC_READ); + if (ret < 0) + goto out; + + ret = regmap_bulk_read(info->max77802->regmap, + MAX77802_RTC_SEC, data, RTC_NR_TIME); + if (ret < 0) { + dev_err(info->dev, "%s: fail to read time reg(%d)\n", __func__, + ret); + goto out; + } + + max77802_rtc_data_to_tm(data, tm, info->rtc_24hr_mode); + + ret = rtc_valid_tm(tm); + +out: + mutex_unlock(&info->lock); + return ret; +} + +static int max77802_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct max77802_rtc_info *info = dev_get_drvdata(dev); + u8 data[RTC_NR_TIME]; + int ret; + + ret = max77802_rtc_tm_to_data(tm, data); + if (ret < 0) + return ret; + + mutex_lock(&info->lock); + + ret = regmap_bulk_write(info->max77802->regmap, + MAX77802_RTC_SEC, data, RTC_NR_TIME); + if (ret < 0) { + dev_err(info->dev, "%s: fail to write time reg(%d)\n", __func__, + ret); + goto out; + } + + ret = max77802_rtc_update(info, MAX77802_RTC_WRITE); + +out: + mutex_unlock(&info->lock); + return ret; +} + +static int max77802_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct max77802_rtc_info *info = dev_get_drvdata(dev); + u8 data[RTC_NR_TIME]; + unsigned int val; + int ret; + + mutex_lock(&info->lock); + + ret = max77802_rtc_update(info, MAX77802_RTC_READ); + if (ret < 0) + goto out; + + ret = regmap_bulk_read(info->max77802->regmap, + MAX77802_ALARM1_SEC, data, RTC_NR_TIME); + if (ret < 0) { + dev_err(info->dev, "%s:%d fail to read alarm reg(%d)\n", + __func__, __LINE__, ret); + goto out; + } + + max77802_rtc_data_to_tm(data, &alrm->time, info->rtc_24hr_mode); + + alrm->enabled = 0; + ret = regmap_read(info->max77802->regmap, + MAX77802_RTC_AE1, &val); + if (ret < 0) { + dev_err(info->dev, "%s:%d fail to read alarm enable(%d)\n", + __func__, __LINE__, ret); + goto out; + } + if (val) + alrm->enabled = 1; + + alrm->pending = 0; + ret = regmap_read(info->max77802->regmap, MAX77802_REG_STATUS2, &val); + if (ret < 0) { + dev_err(info->dev, "%s:%d fail to read status2 reg(%d)\n", + __func__, __LINE__, ret); + goto out; + } + + if (val & (1 << 2)) /* RTCA1 */ + alrm->pending = 1; + +out: + mutex_unlock(&info->lock); + return 0; +} + +static int max77802_rtc_stop_alarm(struct max77802_rtc_info *info) +{ + int ret; + + if (!mutex_is_locked(&info->lock)) + dev_warn(info->dev, "%s: should have mutex locked\n", __func__); + + ret = max77802_rtc_update(info, MAX77802_RTC_READ); + if (ret < 0) + goto out; + + ret = regmap_write(info->max77802->regmap, + MAX77802_RTC_AE1, 0); + if (ret < 0) { + dev_err(info->dev, "%s: fail to write alarm reg(%d)\n", + __func__, ret); + goto out; + } + + ret = max77802_rtc_update(info, MAX77802_RTC_WRITE); +out: + return ret; +} + +static int max77802_rtc_start_alarm(struct max77802_rtc_info *info) +{ + int ret; + + if (!mutex_is_locked(&info->lock)) + dev_warn(info->dev, "%s: should have mutex locked\n", + __func__); + + ret = max77802_rtc_update(info, MAX77802_RTC_READ); + if (ret < 0) + goto out; + + ret = regmap_write(info->max77802->regmap, + MAX77802_RTC_AE1, + ALARM_ENABLE_VALUE); + + if (ret < 0) { + dev_err(info->dev, "%s: fail to read alarm reg(%d)\n", + __func__, ret); + goto out; + } + + ret = max77802_rtc_update(info, MAX77802_RTC_WRITE); +out: + return ret; +} + +static int max77802_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct max77802_rtc_info *info = dev_get_drvdata(dev); + u8 data[RTC_NR_TIME]; + int ret; + + ret = max77802_rtc_tm_to_data(&alrm->time, data); + if (ret < 0) + return ret; + + mutex_lock(&info->lock); + + ret = max77802_rtc_stop_alarm(info); + if (ret < 0) + goto out; + + ret = regmap_bulk_write(info->max77802->regmap, + MAX77802_ALARM1_SEC, data, RTC_NR_TIME); + + if (ret < 0) { + dev_err(info->dev, "%s: fail to write alarm reg(%d)\n", + __func__, ret); + goto out; + } + + ret = max77802_rtc_update(info, MAX77802_RTC_WRITE); + if (ret < 0) + goto out; + + if (alrm->enabled) + ret = max77802_rtc_start_alarm(info); +out: + mutex_unlock(&info->lock); + return ret; +} + +static int max77802_rtc_alarm_irq_enable(struct device *dev, + unsigned int enabled) +{ + struct max77802_rtc_info *info = dev_get_drvdata(dev); + int ret; + + mutex_lock(&info->lock); + if (enabled) + ret = max77802_rtc_start_alarm(info); + else + ret = max77802_rtc_stop_alarm(info); + mutex_unlock(&info->lock); + + return ret; +} + +static irqreturn_t max77802_rtc_alarm_irq(int irq, void *data) +{ + struct max77802_rtc_info *info = data; + + dev_dbg(info->dev, "%s:irq(%d)\n", __func__, irq); + + rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF); + + return IRQ_HANDLED; +} + +static const struct rtc_class_ops max77802_rtc_ops = { + .read_time = max77802_rtc_read_time, + .set_time = max77802_rtc_set_time, + .read_alarm = max77802_rtc_read_alarm, + .set_alarm = max77802_rtc_set_alarm, + .alarm_irq_enable = max77802_rtc_alarm_irq_enable, +}; + +static int max77802_rtc_init_reg(struct max77802_rtc_info *info) +{ + u8 data[2]; + int ret; + + max77802_rtc_update(info, MAX77802_RTC_READ); + + /* Set RTC control register : Binary mode, 24hour mdoe */ + data[0] = (1 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT); + data[1] = (0 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT); + + info->rtc_24hr_mode = 1; + + ret = regmap_bulk_write(info->max77802->regmap, + MAX77802_RTC_CONTROLM, data, ARRAY_SIZE(data)); + if (ret < 0) { + dev_err(info->dev, "%s: fail to write controlm reg(%d)\n", + __func__, ret); + return ret; + } + + ret = max77802_rtc_update(info, MAX77802_RTC_WRITE); + return ret; +} + +static int max77802_rtc_probe(struct platform_device *pdev) +{ + struct max77686_dev *max77802 = dev_get_drvdata(pdev->dev.parent); + struct max77802_rtc_info *info; + int ret; + + dev_dbg(&pdev->dev, "%s\n", __func__); + + info = devm_kzalloc(&pdev->dev, sizeof(struct max77802_rtc_info), + GFP_KERNEL); + if (!info) + return -ENOMEM; + + mutex_init(&info->lock); + info->dev = &pdev->dev; + info->max77802 = max77802; + info->rtc = max77802->i2c; + + platform_set_drvdata(pdev, info); + + ret = max77802_rtc_init_reg(info); + + if (ret < 0) { + dev_err(&pdev->dev, "Failed to initialize RTC reg:%d\n", ret); + return ret; + } + + device_init_wakeup(&pdev->dev, 1); + + info->rtc_dev = devm_rtc_device_register(&pdev->dev, "max77802-rtc", + &max77802_rtc_ops, THIS_MODULE); + + if (IS_ERR(info->rtc_dev)) { + ret = PTR_ERR(info->rtc_dev); + dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret); + if (ret == 0) + ret = -EINVAL; + return ret; + } + info->virq = regmap_irq_get_virq(max77802->rtc_irq_data, + MAX77686_RTCIRQ_RTCA1); + + if (info->virq <= 0) { + dev_err(&pdev->dev, "Failed to get virtual IRQ %d\n", + MAX77686_RTCIRQ_RTCA1); + ret = -EINVAL; + return ret; + } + + ret = devm_request_threaded_irq(&pdev->dev, info->virq, NULL, + max77802_rtc_alarm_irq, 0, "rtc-alarm1", + info); + if (ret < 0) + dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n", + info->virq, ret); + + return ret; +} + +#ifdef CONFIG_PM_SLEEP +static int max77802_rtc_suspend(struct device *dev) +{ + if (device_may_wakeup(dev)) { + struct max77802_rtc_info *info = dev_get_drvdata(dev); + + return enable_irq_wake(info->virq); + } + + return 0; +} + +static int max77802_rtc_resume(struct device *dev) +{ + if (device_may_wakeup(dev)) { + struct max77802_rtc_info *info = dev_get_drvdata(dev); + + return disable_irq_wake(info->virq); + } + + return 0; +} +#endif + +static SIMPLE_DEV_PM_OPS(max77802_rtc_pm_ops, + max77802_rtc_suspend, max77802_rtc_resume); + +static const struct platform_device_id rtc_id[] = { + { "max77802-rtc", 0 }, + {}, +}; + +static struct platform_driver max77802_rtc_driver = { + .driver = { + .name = "max77802-rtc", + .owner = THIS_MODULE, + .pm = &max77802_rtc_pm_ops, + }, + .probe = max77802_rtc_probe, + .id_table = rtc_id, +}; + +module_platform_driver(max77802_rtc_driver); + +MODULE_DESCRIPTION("Maxim MAX77802 RTC driver"); +MODULE_AUTHOR("Simon Glass <sjg@chromium.org>"); +MODULE_LICENSE("GPL");
The MAX7802 PMIC has a Real-Time-Clock (RTC) with two alarms. This patch adds support for the RTC and is based on a driver added by Simon Glass to the Chrome OS kernel 3.8 tree. Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk> --- Changes since v6: - Remove unused code for SMPL and WTSR. Suggested by Krzysztof Kozlowski. - Don't spam the kernel log with unimportant info and just print for debug. Suggested by Krzysztof Kozlowski. - Use ARRAY_SIZE() instead of constant value. Suggested by Krzysztof Kozlowski. - Remove duplicated register setup. Suggested by Krzysztof Kozlowski. - Don't free/unregister managed allocated resources. Suggested by Krzysztof Kozlowski. --- drivers/rtc/Kconfig | 10 + drivers/rtc/Makefile | 1 + drivers/rtc/rtc-max77802.c | 508 +++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 519 insertions(+) create mode 100644 drivers/rtc/rtc-max77802.c