| /* |
| * drivers/rtc/rtc-tps6586x.c |
| * |
| * RTC driver for TI TPS6586x |
| * |
| * Copyright (c) 2010, NVIDIA Corporation. |
| * |
| * 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. |
| * |
| * 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. |
| */ |
| |
| #include <linux/device.h> |
| #include <linux/err.h> |
| #include <linux/init.h> |
| #include <linux/kernel.h> |
| #include <linux/mfd/tps6586x.h> |
| #include <linux/platform_device.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 |
| #define RTC_COUNT4_DUMMYREAD 0xc5 /* start a PMU RTC access by reading the register prior to the RTC_COUNT4 */ |
| #define ALM1_VALID_RANGE_IN_SEC 0x3FFF /*only 14-bits width in second*/ |
| |
| struct tps6586x_rtc { |
| unsigned long epoch_start; |
| int irq; |
| struct rtc_device *rtc; |
| bool irq_en; |
| }; |
| |
| 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 err; |
| int i; |
| |
| err = tps6586x_reads(tps_dev, RTC_COUNT4_DUMMYREAD, sizeof(buff), buff); |
| if (err < 0) { |
| dev_err(dev, "failed to read counter\n"); |
| return err; |
| } |
| |
| 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 err; |
| |
| rtc_tm_to_time(tm, &seconds); |
| |
| if (WARN_ON(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; |
| |
| err = tps6586x_clr_bits(tps_dev, RTC_CTRL, RTC_ENABLE); |
| if (err < 0) { |
| dev_err(dev, "failed to clear RTC_ENABLE\n"); |
| return err; |
| } |
| |
| err = tps6586x_writes(tps_dev, RTC_COUNT4, sizeof(buff), buff); |
| if (err < 0) { |
| dev_err(dev, "failed to program new time\n"); |
| return err; |
| } |
| |
| err = tps6586x_set_bits(tps_dev, RTC_CTRL, RTC_ENABLE); |
| if (err < 0) { |
| dev_err(dev, "failed to set RTC_ENABLE\n"); |
| return err; |
| } |
| |
| 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 err; |
| int i; |
| |
| if (rtc->irq == -1) |
| return -EIO; |
| |
| rtc_tm_to_time(&alrm->time, &seconds); |
| |
| if (WARN_ON(alrm->enabled && (seconds < rtc->epoch_start))) { |
| dev_err(dev, "can't set alarm to requested time\n"); |
| return -EINVAL; |
| } |
| |
| if (alrm->enabled && !rtc->irq_en) { |
| enable_irq(rtc->irq); |
| rtc->irq_en = true; |
| } else if (!alrm->enabled && rtc->irq_en) { |
| disable_irq(rtc->irq); |
| rtc->irq_en = false; |
| } |
| |
| seconds -= rtc->epoch_start; |
| |
| err = tps6586x_reads(tps_dev, RTC_COUNT4_DUMMYREAD, sizeof(rbuff), rbuff); |
| if (err < 0) { |
| dev_err(dev, "failed to read counter\n"); |
| return err; |
| } |
| |
| 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; |
| |
| err = tps6586x_writes(tps_dev, RTC_ALARM1_HI, sizeof(buff), buff); |
| if (err) |
| dev_err(tps_dev, "unable to program alarm\n"); |
| |
| return err; |
| } |
| |
| 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 err; |
| |
| err = tps6586x_reads(tps_dev, RTC_ALARM1_HI, sizeof(buff), buff); |
| if (err) |
| return err; |
| |
| 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 int tps6586x_rtc_alarm_irq_enable(struct device *dev, |
| unsigned int enabled) |
| { |
| struct tps6586x_rtc *rtc = dev_get_drvdata(dev); |
| struct device *tps_dev = to_tps6586x_dev(dev); |
| u8 buff; |
| int err; |
| |
| if (rtc->irq == -1) |
| return -EIO; |
| |
| err = tps6586x_read(tps_dev, RTC_CTRL, &buff); |
| if (err < 0) { |
| dev_err(dev, "failed to read RTC_CTRL\n"); |
| return err; |
| } |
| |
| if ((enabled && (buff & RTC_ENABLE)) || |
| (!enabled && !(buff & RTC_ENABLE))) |
| return 0; |
| |
| if (enabled) { |
| err = tps6586x_set_bits(tps_dev, RTC_CTRL, RTC_ENABLE); |
| if (err < 0) { |
| dev_err(dev, "failed to set RTC_ENABLE\n"); |
| return err; |
| } |
| |
| if (!rtc->irq_en) { |
| enable_irq(rtc->irq); |
| rtc->irq_en = true; |
| } |
| } else { |
| err = tps6586x_clr_bits(tps_dev, RTC_CTRL, RTC_ENABLE); |
| if (err < 0) { |
| dev_err(dev, "failed to clear RTC_ENABLE\n"); |
| return err; |
| } |
| |
| if (rtc->irq_en) { |
| disable_irq(rtc->irq); |
| rtc->irq_en = false; |
| } |
| } |
| |
| 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 device *dev = data; |
| struct tps6586x_rtc *rtc = dev_get_drvdata(dev); |
| |
| rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF); |
| return IRQ_HANDLED; |
| } |
| |
| static int __devinit tps6586x_rtc_probe(struct platform_device *pdev) |
| { |
| struct tps6586x_rtc_platform_data *pdata = pdev->dev.platform_data; |
| struct device *tps_dev = to_tps6586x_dev(&pdev->dev); |
| struct tps6586x_rtc *rtc; |
| int err; |
| struct tps6586x_epoch_start *epoch; |
| |
| if (!pdata) { |
| dev_err(&pdev->dev, "no platform_data specified\n"); |
| return -EINVAL; |
| } |
| |
| rtc = kzalloc(sizeof(*rtc), GFP_KERNEL); |
| |
| if (!rtc) |
| return -ENOMEM; |
| |
| rtc->irq = -1; |
| |
| if (pdata->irq < 0) |
| dev_warn(&pdev->dev, "no IRQ specified, wakeup is disabled\n"); |
| |
| epoch = &pdata->start; |
| rtc->epoch_start = mktime(epoch->year, epoch->month, epoch->day, |
| epoch->hour, epoch->min, epoch->sec); |
| |
| dev_set_drvdata(&pdev->dev, rtc); |
| |
| device_init_wakeup(&pdev->dev, 1); |
| |
| rtc->rtc = rtc_device_register("tps6586x-rtc", &pdev->dev, |
| &tps6586x_rtc_ops, THIS_MODULE); |
| |
| if (IS_ERR(rtc->rtc)) { |
| err = PTR_ERR(rtc->rtc); |
| goto fail; |
| } |
| |
| /* 1 kHz tick mode, enable tick counting */ |
| err = tps6586x_update(tps_dev, RTC_CTRL, |
| RTC_ENABLE | OSC_SRC_SEL | ((pdata->cl_sel << CL_SEL_POS) & |
| CL_SEL_MASK), |
| RTC_ENABLE | OSC_SRC_SEL | PRE_BYPASS | CL_SEL_MASK); |
| if (err < 0) { |
| dev_err(&pdev->dev, "unable to start counter\n"); |
| goto fail; |
| } |
| |
| if (pdata && (pdata->irq >= 0)) { |
| rtc->irq = pdata->irq; |
| err = request_threaded_irq(pdata->irq, NULL, tps6586x_rtc_irq, |
| IRQF_ONESHOT, "tps6586x-rtc", |
| &pdev->dev); |
| if (err) { |
| dev_warn(&pdev->dev, "unable to request IRQ(%d)\n", rtc->irq); |
| rtc->irq = -1; |
| } else { |
| enable_irq_wake(rtc->irq); |
| disable_irq(rtc->irq); |
| } |
| } |
| |
| return 0; |
| |
| fail: |
| if (!IS_ERR_OR_NULL(rtc->rtc)) |
| rtc_device_unregister(rtc->rtc); |
| device_init_wakeup(&pdev->dev, 0); |
| kfree(rtc); |
| return err; |
| } |
| |
| static int __devexit tps6586x_rtc_remove(struct platform_device *pdev) |
| { |
| struct tps6586x_rtc *rtc = dev_get_drvdata(&pdev->dev); |
| |
| if (rtc->irq != -1) |
| free_irq(rtc->irq, rtc); |
| rtc_device_unregister(rtc->rtc); |
| kfree(rtc); |
| return 0; |
| } |
| |
| static struct platform_driver tps6586x_rtc_driver = { |
| .driver = { |
| .name = "tps6586x-rtc", |
| .owner = THIS_MODULE, |
| }, |
| .probe = tps6586x_rtc_probe, |
| .remove = __devexit_p(tps6586x_rtc_remove), |
| }; |
| |
| static int __init tps6586x_rtc_init(void) |
| { |
| return platform_driver_register(&tps6586x_rtc_driver); |
| } |
| module_init(tps6586x_rtc_init); |
| |
| static void __exit tps6586x_rtc_exit(void) |
| { |
| platform_driver_unregister(&tps6586x_rtc_driver); |
| } |
| module_exit(tps6586x_rtc_exit); |
| |
| MODULE_DESCRIPTION("TI TPS6586x RTC driver"); |
| MODULE_AUTHOR("NVIDIA Corporation"); |
| MODULE_LICENSE("GPL"); |
| MODULE_ALIAS("platform:rtc-tps6586x"); |