| /* |
| * rtc-tps80031.c -- TI TPS80031/TPS80032 RTC driver |
| * |
| * RTC driver for TI TPS80031/TPS80032 Fully Integrated |
| * Power Management with Power Path and Battery Charger |
| * |
| * Copyright (c) 2012, NVIDIA Corporation. |
| * |
| * Author: Laxman Dewangan <ldewangan@nvidia.com> |
| * |
| * 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 version 2. |
| * |
| * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind, |
| * whether express or implied; 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., 59 Temple Place, Suite 330, Boston, MA |
| * 02111-1307, USA |
| */ |
| |
| #include <linux/bcd.h> |
| #include <linux/device.h> |
| #include <linux/err.h> |
| #include <linux/init.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/mfd/tps80031.h> |
| #include <linux/platform_device.h> |
| #include <linux/pm.h> |
| #include <linux/rtc.h> |
| #include <linux/slab.h> |
| |
| #define ENABLE_ALARM_INT 0x08 |
| #define ALARM_INT_STATUS 0x40 |
| |
| /** |
| * Setting bit to 1 in STOP_RTC will run the RTC and |
| * setting this bit to 0 will freeze RTC. |
| */ |
| #define STOP_RTC 0x1 |
| |
| /* Power on reset Values of RTC registers */ |
| #define TPS80031_RTC_POR_YEAR 0 |
| #define TPS80031_RTC_POR_MONTH 1 |
| #define TPS80031_RTC_POR_DAY 1 |
| |
| /* Numbers of registers for time and alarms */ |
| #define TPS80031_RTC_TIME_NUM_REGS 7 |
| #define TPS80031_RTC_ALARM_NUM_REGS 6 |
| |
| /** |
| * PMU RTC have only 2 nibbles to store year information, so using an |
| * offset of 100 to set the base year as 2000 for our driver. |
| */ |
| #define RTC_YEAR_OFFSET 100 |
| |
| struct tps80031_rtc { |
| struct rtc_device *rtc; |
| int irq; |
| }; |
| |
| static int tps80031_rtc_read_time(struct device *dev, struct rtc_time *tm) |
| { |
| u8 buff[TPS80031_RTC_TIME_NUM_REGS]; |
| int ret; |
| |
| ret = tps80031_reads(dev->parent, TPS80031_SLAVE_ID1, |
| TPS80031_SECONDS_REG, TPS80031_RTC_TIME_NUM_REGS, buff); |
| if (ret < 0) { |
| dev_err(dev, "reading RTC_SECONDS_REG failed, err = %d\n", ret); |
| return ret; |
| } |
| |
| tm->tm_sec = bcd2bin(buff[0]); |
| tm->tm_min = bcd2bin(buff[1]); |
| tm->tm_hour = bcd2bin(buff[2]); |
| tm->tm_mday = bcd2bin(buff[3]); |
| tm->tm_mon = bcd2bin(buff[4]) - 1; |
| tm->tm_year = bcd2bin(buff[5]) + RTC_YEAR_OFFSET; |
| tm->tm_wday = bcd2bin(buff[6]); |
| return 0; |
| } |
| |
| static int tps80031_rtc_set_time(struct device *dev, struct rtc_time *tm) |
| { |
| u8 buff[7]; |
| int ret; |
| |
| buff[0] = bin2bcd(tm->tm_sec); |
| buff[1] = bin2bcd(tm->tm_min); |
| buff[2] = bin2bcd(tm->tm_hour); |
| buff[3] = bin2bcd(tm->tm_mday); |
| buff[4] = bin2bcd(tm->tm_mon + 1); |
| buff[5] = bin2bcd(tm->tm_year % RTC_YEAR_OFFSET); |
| buff[6] = bin2bcd(tm->tm_wday); |
| |
| /* Stop RTC while updating the RTC time registers */ |
| ret = tps80031_clr_bits(dev->parent, TPS80031_SLAVE_ID1, |
| TPS80031_RTC_CTRL_REG, STOP_RTC); |
| if (ret < 0) { |
| dev_err(dev->parent, "Stop RTC failed, err = %d\n", ret); |
| return ret; |
| } |
| |
| ret = tps80031_writes(dev->parent, TPS80031_SLAVE_ID1, |
| TPS80031_SECONDS_REG, |
| TPS80031_RTC_TIME_NUM_REGS, buff); |
| if (ret < 0) { |
| dev_err(dev, "writing RTC_SECONDS_REG failed, err %d\n", ret); |
| return ret; |
| } |
| |
| ret = tps80031_set_bits(dev->parent, TPS80031_SLAVE_ID1, |
| TPS80031_RTC_CTRL_REG, STOP_RTC); |
| if (ret < 0) |
| dev_err(dev->parent, "Start RTC failed, err = %d\n", ret); |
| return ret; |
| } |
| |
| static int tps80031_rtc_alarm_irq_enable(struct device *dev, |
| unsigned int enable) |
| { |
| int ret; |
| |
| if (enable) |
| ret = tps80031_set_bits(dev->parent, TPS80031_SLAVE_ID1, |
| TPS80031_RTC_INTERRUPTS_REG, ENABLE_ALARM_INT); |
| else |
| ret = tps80031_clr_bits(dev->parent, TPS80031_SLAVE_ID1, |
| TPS80031_RTC_INTERRUPTS_REG, ENABLE_ALARM_INT); |
| if (ret < 0) { |
| dev_err(dev, "Update on RTC_INT failed, err = %d\n", ret); |
| return ret; |
| } |
| return 0; |
| } |
| |
| static int tps80031_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) |
| { |
| u8 buff[TPS80031_RTC_ALARM_NUM_REGS]; |
| int ret; |
| |
| buff[0] = bin2bcd(alrm->time.tm_sec); |
| buff[1] = bin2bcd(alrm->time.tm_min); |
| buff[2] = bin2bcd(alrm->time.tm_hour); |
| buff[3] = bin2bcd(alrm->time.tm_mday); |
| buff[4] = bin2bcd(alrm->time.tm_mon + 1); |
| buff[5] = bin2bcd(alrm->time.tm_year % RTC_YEAR_OFFSET); |
| ret = tps80031_writes(dev->parent, TPS80031_SLAVE_ID1, |
| TPS80031_ALARM_SECONDS_REG, |
| TPS80031_RTC_ALARM_NUM_REGS, buff); |
| if (ret < 0) { |
| dev_err(dev, "Writing RTC_ALARM failed, err %d\n", ret); |
| return ret; |
| } |
| return tps80031_rtc_alarm_irq_enable(dev, alrm->enabled); |
| } |
| |
| static int tps80031_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) |
| { |
| u8 buff[6]; |
| int ret; |
| |
| ret = tps80031_reads(dev->parent, TPS80031_SLAVE_ID1, |
| TPS80031_ALARM_SECONDS_REG, |
| TPS80031_RTC_ALARM_NUM_REGS, buff); |
| if (ret < 0) { |
| dev_err(dev->parent, |
| "reading RTC_ALARM failed, err = %d\n", ret); |
| return ret; |
| } |
| |
| alrm->time.tm_sec = bcd2bin(buff[0]); |
| alrm->time.tm_min = bcd2bin(buff[1]); |
| alrm->time.tm_hour = bcd2bin(buff[2]); |
| alrm->time.tm_mday = bcd2bin(buff[3]); |
| alrm->time.tm_mon = bcd2bin(buff[4]) - 1; |
| alrm->time.tm_year = bcd2bin(buff[5]) + RTC_YEAR_OFFSET; |
| return 0; |
| } |
| |
| static int clear_alarm_int_status(struct device *dev, struct tps80031_rtc *rtc) |
| { |
| int ret; |
| u8 buf; |
| |
| /** |
| * As per datasheet, A dummy read of this RTC_STATUS_REG register |
| * is necessary before each I2C read in order to update the status |
| * register value. |
| */ |
| ret = tps80031_read(dev->parent, TPS80031_SLAVE_ID1, |
| TPS80031_RTC_STATUS_REG, &buf); |
| if (ret < 0) { |
| dev_err(dev, "reading RTC_STATUS failed. err = %d\n", ret); |
| return ret; |
| } |
| |
| /* clear Alarm status bits.*/ |
| ret = tps80031_set_bits(dev->parent, TPS80031_SLAVE_ID1, |
| TPS80031_RTC_STATUS_REG, ALARM_INT_STATUS); |
| if (ret < 0) { |
| dev_err(dev, "clear Alarm INT failed, err = %d\n", ret); |
| return ret; |
| } |
| return 0; |
| } |
| |
| static irqreturn_t tps80031_rtc_irq(int irq, void *data) |
| { |
| struct device *dev = data; |
| struct tps80031_rtc *rtc = dev_get_drvdata(dev); |
| int ret; |
| |
| ret = clear_alarm_int_status(dev, rtc); |
| if (ret < 0) |
| return ret; |
| |
| rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF); |
| return IRQ_HANDLED; |
| } |
| |
| static const struct rtc_class_ops tps80031_rtc_ops = { |
| .read_time = tps80031_rtc_read_time, |
| .set_time = tps80031_rtc_set_time, |
| .set_alarm = tps80031_rtc_set_alarm, |
| .read_alarm = tps80031_rtc_read_alarm, |
| .alarm_irq_enable = tps80031_rtc_alarm_irq_enable, |
| }; |
| |
| static int tps80031_rtc_probe(struct platform_device *pdev) |
| { |
| struct tps80031_rtc *rtc; |
| struct rtc_time tm; |
| int ret; |
| |
| rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL); |
| if (!rtc) |
| return -ENOMEM; |
| |
| rtc->irq = platform_get_irq(pdev, 0); |
| platform_set_drvdata(pdev, rtc); |
| |
| /* Start RTC */ |
| ret = tps80031_set_bits(pdev->dev.parent, TPS80031_SLAVE_ID1, |
| TPS80031_RTC_CTRL_REG, STOP_RTC); |
| if (ret < 0) { |
| dev_err(&pdev->dev, "failed to start RTC. err = %d\n", ret); |
| return ret; |
| } |
| |
| /* If RTC have POR values, set time 01:01:2000 */ |
| tps80031_rtc_read_time(&pdev->dev, &tm); |
| if ((tm.tm_year == RTC_YEAR_OFFSET + TPS80031_RTC_POR_YEAR) && |
| (tm.tm_mon == (TPS80031_RTC_POR_MONTH - 1)) && |
| (tm.tm_mday == TPS80031_RTC_POR_DAY)) { |
| tm.tm_year = 2000; |
| tm.tm_mday = 1; |
| tm.tm_mon = 1; |
| ret = tps80031_rtc_set_time(&pdev->dev, &tm); |
| if (ret < 0) { |
| dev_err(&pdev->dev, |
| "RTC set time failed, err = %d\n", ret); |
| return ret; |
| } |
| } |
| |
| /* Clear alarm intretupt status if it is there */ |
| ret = clear_alarm_int_status(&pdev->dev, rtc); |
| if (ret < 0) { |
| dev_err(&pdev->dev, "Clear alarm int failed, err = %d\n", ret); |
| return ret; |
| } |
| |
| rtc->rtc = rtc_device_register(pdev->name, &pdev->dev, |
| &tps80031_rtc_ops, THIS_MODULE); |
| if (IS_ERR(rtc->rtc)) { |
| ret = PTR_ERR(rtc->rtc); |
| dev_err(&pdev->dev, "RTC registration failed, err %d\n", ret); |
| return ret; |
| } |
| |
| ret = request_threaded_irq(rtc->irq, NULL, tps80031_rtc_irq, |
| IRQF_ONESHOT | IRQF_EARLY_RESUME, |
| dev_name(&pdev->dev), rtc); |
| if (ret < 0) { |
| dev_err(&pdev->dev, "request IRQ:%d failed, err = %d\n", |
| rtc->irq, ret); |
| rtc_device_unregister(rtc->rtc); |
| return ret; |
| } |
| device_set_wakeup_capable(&pdev->dev, 1); |
| return 0; |
| } |
| |
| static int tps80031_rtc_remove(struct platform_device *pdev) |
| { |
| struct tps80031_rtc *rtc = platform_get_drvdata(pdev); |
| |
| free_irq(rtc->irq, rtc); |
| rtc_device_unregister(rtc->rtc); |
| return 0; |
| } |
| |
| #ifdef CONFIG_PM_SLEEP |
| static int tps80031_rtc_suspend(struct device *dev) |
| { |
| struct tps80031_rtc *rtc = dev_get_drvdata(dev); |
| |
| if (device_may_wakeup(dev)) |
| enable_irq_wake(rtc->irq); |
| return 0; |
| } |
| |
| static int tps80031_rtc_resume(struct device *dev) |
| { |
| struct tps80031_rtc *rtc = dev_get_drvdata(dev); |
| |
| if (device_may_wakeup(dev)) |
| disable_irq_wake(rtc->irq); |
| return 0; |
| }; |
| #endif |
| |
| static const struct dev_pm_ops tps80031_pm_ops = { |
| SET_SYSTEM_SLEEP_PM_OPS(tps80031_rtc_suspend, tps80031_rtc_resume) |
| }; |
| |
| static struct platform_driver tps80031_rtc_driver = { |
| .driver = { |
| .name = "tps80031-rtc", |
| .owner = THIS_MODULE, |
| .pm = &tps80031_pm_ops, |
| }, |
| .probe = tps80031_rtc_probe, |
| .remove = tps80031_rtc_remove, |
| }; |
| |
| module_platform_driver(tps80031_rtc_driver); |
| |
| MODULE_ALIAS("platform:tps80031-rtc"); |
| MODULE_DESCRIPTION("TI TPS80031/TPS80032 RTC driver"); |
| MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); |
| MODULE_LICENSE("GPL v2"); |