| /* |
| * rtc-tps6586x.c: RTC driver for TI PMIC TPS6586X |
| * |
| * 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/device.h> |
| #include <linux/err.h> |
| #include <linux/init.h> |
| #include <linux/kernel.h> |
| #include <linux/mfd/tps6586x.h> |
| #include <linux/module.h> |
| #include <linux/platform_device.h> |
| #include <linux/pm_runtime.h> |
| #include <linux/rtc.h> |
| #include <linux/slab.h> |
| |
| #define RTC_CTRL 0xc0 |
| #define POR_RESET_N BIT(7) |
| #define OSC_SRC_SEL BIT(6) |
| #define RTC_ENABLE BIT(5) /* enables alarm */ |
| #define RTC_BUF_ENABLE BIT(4) /* 32 KHz buffer enable */ |
| #define PRE_BYPASS BIT(3) /* 0=1KHz or 1=32KHz updates */ |
| #define CL_SEL_MASK (BIT(2)|BIT(1)) |
| #define CL_SEL_POS 1 |
| #define RTC_ALARM1_HI 0xc1 |
| #define RTC_COUNT4 0xc6 |
| |
| /* start a PMU RTC access by reading the register prior to the RTC_COUNT4 */ |
| #define RTC_COUNT4_DUMMYREAD 0xc5 |
| |
| /*only 14-bits width in second*/ |
| #define ALM1_VALID_RANGE_IN_SEC 0x3FFF |
| |
| #define TPS6586X_RTC_CL_SEL_1_5PF 0x0 |
| #define TPS6586X_RTC_CL_SEL_6_5PF 0x1 |
| #define TPS6586X_RTC_CL_SEL_7_5PF 0x2 |
| #define TPS6586X_RTC_CL_SEL_12_5PF 0x3 |
| |
| struct tps6586x_rtc { |
| struct device *dev; |
| struct rtc_device *rtc; |
| int irq; |
| bool irq_en; |
| unsigned long long epoch_start; |
| }; |
| |
| static inline struct device *to_tps6586x_dev(struct device *dev) |
| { |
| return dev->parent; |
| } |
| |
| static int tps6586x_rtc_read_time(struct device *dev, struct rtc_time *tm) |
| { |
| struct tps6586x_rtc *rtc = dev_get_drvdata(dev); |
| struct device *tps_dev = to_tps6586x_dev(dev); |
| unsigned long long ticks = 0; |
| unsigned long seconds; |
| u8 buff[6]; |
| int ret; |
| int i; |
| |
| ret = tps6586x_reads(tps_dev, RTC_COUNT4_DUMMYREAD, sizeof(buff), buff); |
| if (ret < 0) { |
| dev_err(dev, "read counter failed with err %d\n", ret); |
| return ret; |
| } |
| |
| for (i = 1; i < sizeof(buff); i++) { |
| ticks <<= 8; |
| ticks |= buff[i]; |
| } |
| |
| seconds = ticks >> 10; |
| seconds += rtc->epoch_start; |
| rtc_time_to_tm(seconds, tm); |
| return rtc_valid_tm(tm); |
| } |
| |
| static int tps6586x_rtc_set_time(struct device *dev, struct rtc_time *tm) |
| { |
| struct tps6586x_rtc *rtc = dev_get_drvdata(dev); |
| struct device *tps_dev = to_tps6586x_dev(dev); |
| unsigned long long ticks; |
| unsigned long seconds; |
| u8 buff[5]; |
| int ret; |
| |
| rtc_tm_to_time(tm, &seconds); |
| if (seconds < rtc->epoch_start) { |
| dev_err(dev, "requested time unsupported\n"); |
| return -EINVAL; |
| } |
| seconds -= rtc->epoch_start; |
| |
| ticks = (unsigned long long)seconds << 10; |
| buff[0] = (ticks >> 32) & 0xff; |
| buff[1] = (ticks >> 24) & 0xff; |
| buff[2] = (ticks >> 16) & 0xff; |
| buff[3] = (ticks >> 8) & 0xff; |
| buff[4] = ticks & 0xff; |
| |
| /* Disable RTC before changing time */ |
| ret = tps6586x_clr_bits(tps_dev, RTC_CTRL, RTC_ENABLE); |
| if (ret < 0) { |
| dev_err(dev, "failed to clear RTC_ENABLE\n"); |
| return ret; |
| } |
| |
| ret = tps6586x_writes(tps_dev, RTC_COUNT4, sizeof(buff), buff); |
| if (ret < 0) { |
| dev_err(dev, "failed to program new time\n"); |
| return ret; |
| } |
| |
| /* Enable RTC */ |
| ret = tps6586x_set_bits(tps_dev, RTC_CTRL, RTC_ENABLE); |
| if (ret < 0) { |
| dev_err(dev, "failed to set RTC_ENABLE\n"); |
| return ret; |
| } |
| return 0; |
| } |
| |
| static int tps6586x_rtc_alarm_irq_enable(struct device *dev, |
| unsigned int enabled) |
| { |
| struct tps6586x_rtc *rtc = dev_get_drvdata(dev); |
| |
| if (enabled && !rtc->irq_en) { |
| enable_irq(rtc->irq); |
| rtc->irq_en = true; |
| } else if (!enabled && rtc->irq_en) { |
| disable_irq(rtc->irq); |
| rtc->irq_en = false; |
| } |
| return 0; |
| } |
| |
| static int tps6586x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) |
| { |
| struct tps6586x_rtc *rtc = dev_get_drvdata(dev); |
| struct device *tps_dev = to_tps6586x_dev(dev); |
| unsigned long seconds; |
| unsigned long ticks; |
| unsigned long rtc_current_time; |
| unsigned long long rticks = 0; |
| u8 buff[3]; |
| u8 rbuff[6]; |
| int ret; |
| int i; |
| |
| rtc_tm_to_time(&alrm->time, &seconds); |
| |
| if (alrm->enabled && (seconds < rtc->epoch_start)) { |
| dev_err(dev, "can't set alarm to requested time\n"); |
| return -EINVAL; |
| } |
| |
| ret = tps6586x_rtc_alarm_irq_enable(dev, alrm->enabled); |
| if (ret < 0) { |
| dev_err(dev, "can't set alarm irq, err %d\n", ret); |
| return ret; |
| } |
| |
| seconds -= rtc->epoch_start; |
| ret = tps6586x_reads(tps_dev, RTC_COUNT4_DUMMYREAD, |
| sizeof(rbuff), rbuff); |
| if (ret < 0) { |
| dev_err(dev, "read counter failed with err %d\n", ret); |
| return ret; |
| } |
| |
| for (i = 1; i < sizeof(rbuff); i++) { |
| rticks <<= 8; |
| rticks |= rbuff[i]; |
| } |
| |
| rtc_current_time = rticks >> 10; |
| if ((seconds - rtc_current_time) > ALM1_VALID_RANGE_IN_SEC) |
| seconds = rtc_current_time - 1; |
| |
| ticks = (unsigned long long)seconds << 10; |
| buff[0] = (ticks >> 16) & 0xff; |
| buff[1] = (ticks >> 8) & 0xff; |
| buff[2] = ticks & 0xff; |
| |
| ret = tps6586x_writes(tps_dev, RTC_ALARM1_HI, sizeof(buff), buff); |
| if (ret) |
| dev_err(dev, "programming alarm failed with err %d\n", ret); |
| |
| return ret; |
| } |
| |
| static int tps6586x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) |
| { |
| struct tps6586x_rtc *rtc = dev_get_drvdata(dev); |
| struct device *tps_dev = to_tps6586x_dev(dev); |
| unsigned long ticks; |
| unsigned long seconds; |
| u8 buff[3]; |
| int ret; |
| |
| ret = tps6586x_reads(tps_dev, RTC_ALARM1_HI, sizeof(buff), buff); |
| if (ret) { |
| dev_err(dev, "read RTC_ALARM1_HI failed with err %d\n", ret); |
| return ret; |
| } |
| |
| ticks = (buff[0] << 16) | (buff[1] << 8) | buff[2]; |
| seconds = ticks >> 10; |
| seconds += rtc->epoch_start; |
| |
| rtc_time_to_tm(seconds, &alrm->time); |
| return 0; |
| } |
| |
| static const struct rtc_class_ops tps6586x_rtc_ops = { |
| .read_time = tps6586x_rtc_read_time, |
| .set_time = tps6586x_rtc_set_time, |
| .set_alarm = tps6586x_rtc_set_alarm, |
| .read_alarm = tps6586x_rtc_read_alarm, |
| .alarm_irq_enable = tps6586x_rtc_alarm_irq_enable, |
| }; |
| |
| static irqreturn_t tps6586x_rtc_irq(int irq, void *data) |
| { |
| struct tps6586x_rtc *rtc = data; |
| |
| rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF); |
| return IRQ_HANDLED; |
| } |
| |
| static int tps6586x_rtc_probe(struct platform_device *pdev) |
| { |
| struct device *tps_dev = to_tps6586x_dev(&pdev->dev); |
| struct tps6586x_rtc *rtc; |
| int ret; |
| |
| rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL); |
| if (!rtc) |
| return -ENOMEM; |
| |
| rtc->dev = &pdev->dev; |
| rtc->irq = platform_get_irq(pdev, 0); |
| |
| /* Set epoch start as 00:00:00:01:01:2009 */ |
| rtc->epoch_start = mktime(2009, 1, 1, 0, 0, 0); |
| |
| /* 1 kHz tick mode, enable tick counting */ |
| ret = tps6586x_update(tps_dev, RTC_CTRL, |
| RTC_ENABLE | OSC_SRC_SEL | |
| ((TPS6586X_RTC_CL_SEL_1_5PF << CL_SEL_POS) & CL_SEL_MASK), |
| RTC_ENABLE | OSC_SRC_SEL | PRE_BYPASS | CL_SEL_MASK); |
| if (ret < 0) { |
| dev_err(&pdev->dev, "unable to start counter\n"); |
| return ret; |
| } |
| |
| device_init_wakeup(&pdev->dev, 1); |
| |
| platform_set_drvdata(pdev, rtc); |
| rtc->rtc = devm_rtc_device_register(&pdev->dev, dev_name(&pdev->dev), |
| &tps6586x_rtc_ops, THIS_MODULE); |
| if (IS_ERR(rtc->rtc)) { |
| ret = PTR_ERR(rtc->rtc); |
| dev_err(&pdev->dev, "RTC device register: ret %d\n", ret); |
| goto fail_rtc_register; |
| } |
| |
| ret = devm_request_threaded_irq(&pdev->dev, rtc->irq, NULL, |
| tps6586x_rtc_irq, |
| IRQF_ONESHOT, |
| dev_name(&pdev->dev), rtc); |
| if (ret < 0) { |
| dev_err(&pdev->dev, "request IRQ(%d) failed with ret %d\n", |
| rtc->irq, ret); |
| goto fail_rtc_register; |
| } |
| disable_irq(rtc->irq); |
| return 0; |
| |
| fail_rtc_register: |
| tps6586x_update(tps_dev, RTC_CTRL, 0, |
| RTC_ENABLE | OSC_SRC_SEL | PRE_BYPASS | CL_SEL_MASK); |
| return ret; |
| }; |
| |
| static int tps6586x_rtc_remove(struct platform_device *pdev) |
| { |
| struct device *tps_dev = to_tps6586x_dev(&pdev->dev); |
| |
| tps6586x_update(tps_dev, RTC_CTRL, 0, |
| RTC_ENABLE | OSC_SRC_SEL | PRE_BYPASS | CL_SEL_MASK); |
| return 0; |
| } |
| |
| #ifdef CONFIG_PM_SLEEP |
| static int tps6586x_rtc_suspend(struct device *dev) |
| { |
| struct tps6586x_rtc *rtc = dev_get_drvdata(dev); |
| |
| if (device_may_wakeup(dev)) |
| enable_irq_wake(rtc->irq); |
| return 0; |
| } |
| |
| static int tps6586x_rtc_resume(struct device *dev) |
| { |
| struct tps6586x_rtc *rtc = dev_get_drvdata(dev); |
| |
| if (device_may_wakeup(dev)) |
| disable_irq_wake(rtc->irq); |
| return 0; |
| } |
| #endif |
| |
| static SIMPLE_DEV_PM_OPS(tps6586x_pm_ops, tps6586x_rtc_suspend, |
| tps6586x_rtc_resume); |
| |
| static struct platform_driver tps6586x_rtc_driver = { |
| .driver = { |
| .name = "tps6586x-rtc", |
| .pm = &tps6586x_pm_ops, |
| }, |
| .probe = tps6586x_rtc_probe, |
| .remove = tps6586x_rtc_remove, |
| }; |
| module_platform_driver(tps6586x_rtc_driver); |
| |
| MODULE_ALIAS("platform:rtc-tps6586x"); |
| MODULE_DESCRIPTION("TI TPS6586x RTC driver"); |
| MODULE_AUTHOR("Laxman dewangan <ldewangan@nvidia.com>"); |
| MODULE_LICENSE("GPL v2"); |