| /* |
| * TI LP8788 MFD - rtc driver |
| * |
| * Copyright 2012 Texas Instruments |
| * |
| * Author: Milo(Woogyom) Kim <milo.kim@ti.com> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| * |
| */ |
| |
| #include <linux/err.h> |
| #include <linux/irqdomain.h> |
| #include <linux/mfd/lp8788.h> |
| #include <linux/module.h> |
| #include <linux/platform_device.h> |
| #include <linux/rtc.h> |
| #include <linux/slab.h> |
| |
| /* register address */ |
| #define LP8788_INTEN_3 0x05 |
| #define LP8788_RTC_UNLOCK 0x64 |
| #define LP8788_RTC_SEC 0x70 |
| #define LP8788_ALM1_SEC 0x77 |
| #define LP8788_ALM1_EN 0x7D |
| #define LP8788_ALM2_SEC 0x7E |
| #define LP8788_ALM2_EN 0x84 |
| |
| /* mask/shift bits */ |
| #define LP8788_INT_RTC_ALM1_M BIT(1) /* Addr 05h */ |
| #define LP8788_INT_RTC_ALM1_S 1 |
| #define LP8788_INT_RTC_ALM2_M BIT(2) /* Addr 05h */ |
| #define LP8788_INT_RTC_ALM2_S 2 |
| #define LP8788_ALM_EN_M BIT(7) /* Addr 7Dh or 84h */ |
| #define LP8788_ALM_EN_S 7 |
| |
| #define DEFAULT_ALARM_SEL LP8788_ALARM_1 |
| #define LP8788_MONTH_OFFSET 1 |
| #define LP8788_BASE_YEAR 2000 |
| #define MAX_WDAY_BITS 7 |
| #define LP8788_WDAY_SET 1 |
| #define RTC_UNLOCK 0x1 |
| #define RTC_LATCH 0x2 |
| #define ALARM_IRQ_FLAG (RTC_IRQF | RTC_AF) |
| |
| enum lp8788_time { |
| LPTIME_SEC, |
| LPTIME_MIN, |
| LPTIME_HOUR, |
| LPTIME_MDAY, |
| LPTIME_MON, |
| LPTIME_YEAR, |
| LPTIME_WDAY, |
| LPTIME_MAX, |
| }; |
| |
| struct lp8788_rtc { |
| struct lp8788 *lp; |
| struct rtc_device *rdev; |
| enum lp8788_alarm_sel alarm; |
| int irq; |
| }; |
| |
| static const u8 addr_alarm_sec[LP8788_ALARM_MAX] = { |
| LP8788_ALM1_SEC, |
| LP8788_ALM2_SEC, |
| }; |
| |
| static const u8 addr_alarm_en[LP8788_ALARM_MAX] = { |
| LP8788_ALM1_EN, |
| LP8788_ALM2_EN, |
| }; |
| |
| static const u8 mask_alarm_en[LP8788_ALARM_MAX] = { |
| LP8788_INT_RTC_ALM1_M, |
| LP8788_INT_RTC_ALM2_M, |
| }; |
| |
| static const u8 shift_alarm_en[LP8788_ALARM_MAX] = { |
| LP8788_INT_RTC_ALM1_S, |
| LP8788_INT_RTC_ALM2_S, |
| }; |
| |
| static int _to_tm_wday(u8 lp8788_wday) |
| { |
| int i; |
| |
| if (lp8788_wday == 0) |
| return 0; |
| |
| /* lookup defined weekday from read register value */ |
| for (i = 0; i < MAX_WDAY_BITS; i++) { |
| if ((lp8788_wday >> i) == LP8788_WDAY_SET) |
| break; |
| } |
| |
| return i + 1; |
| } |
| |
| static inline int _to_lp8788_wday(int tm_wday) |
| { |
| return LP8788_WDAY_SET << (tm_wday - 1); |
| } |
| |
| static void lp8788_rtc_unlock(struct lp8788 *lp) |
| { |
| lp8788_write_byte(lp, LP8788_RTC_UNLOCK, RTC_UNLOCK); |
| lp8788_write_byte(lp, LP8788_RTC_UNLOCK, RTC_LATCH); |
| } |
| |
| static int lp8788_rtc_read_time(struct device *dev, struct rtc_time *tm) |
| { |
| struct lp8788_rtc *rtc = dev_get_drvdata(dev); |
| struct lp8788 *lp = rtc->lp; |
| u8 data[LPTIME_MAX]; |
| int ret; |
| |
| lp8788_rtc_unlock(lp); |
| |
| ret = lp8788_read_multi_bytes(lp, LP8788_RTC_SEC, data, LPTIME_MAX); |
| if (ret) |
| return ret; |
| |
| tm->tm_sec = data[LPTIME_SEC]; |
| tm->tm_min = data[LPTIME_MIN]; |
| tm->tm_hour = data[LPTIME_HOUR]; |
| tm->tm_mday = data[LPTIME_MDAY]; |
| tm->tm_mon = data[LPTIME_MON] - LP8788_MONTH_OFFSET; |
| tm->tm_year = data[LPTIME_YEAR] + LP8788_BASE_YEAR - 1900; |
| tm->tm_wday = _to_tm_wday(data[LPTIME_WDAY]); |
| |
| return 0; |
| } |
| |
| static int lp8788_rtc_set_time(struct device *dev, struct rtc_time *tm) |
| { |
| struct lp8788_rtc *rtc = dev_get_drvdata(dev); |
| struct lp8788 *lp = rtc->lp; |
| u8 data[LPTIME_MAX - 1]; |
| int ret, i, year; |
| |
| year = tm->tm_year + 1900 - LP8788_BASE_YEAR; |
| if (year < 0) { |
| dev_err(lp->dev, "invalid year: %d\n", year); |
| return -EINVAL; |
| } |
| |
| /* because rtc weekday is a readonly register, do not update */ |
| data[LPTIME_SEC] = tm->tm_sec; |
| data[LPTIME_MIN] = tm->tm_min; |
| data[LPTIME_HOUR] = tm->tm_hour; |
| data[LPTIME_MDAY] = tm->tm_mday; |
| data[LPTIME_MON] = tm->tm_mon + LP8788_MONTH_OFFSET; |
| data[LPTIME_YEAR] = year; |
| |
| for (i = 0; i < ARRAY_SIZE(data); i++) { |
| ret = lp8788_write_byte(lp, LP8788_RTC_SEC + i, data[i]); |
| if (ret) |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| static int lp8788_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) |
| { |
| struct lp8788_rtc *rtc = dev_get_drvdata(dev); |
| struct lp8788 *lp = rtc->lp; |
| struct rtc_time *tm = &alarm->time; |
| u8 addr, data[LPTIME_MAX]; |
| int ret; |
| |
| addr = addr_alarm_sec[rtc->alarm]; |
| ret = lp8788_read_multi_bytes(lp, addr, data, LPTIME_MAX); |
| if (ret) |
| return ret; |
| |
| tm->tm_sec = data[LPTIME_SEC]; |
| tm->tm_min = data[LPTIME_MIN]; |
| tm->tm_hour = data[LPTIME_HOUR]; |
| tm->tm_mday = data[LPTIME_MDAY]; |
| tm->tm_mon = data[LPTIME_MON] - LP8788_MONTH_OFFSET; |
| tm->tm_year = data[LPTIME_YEAR] + LP8788_BASE_YEAR - 1900; |
| tm->tm_wday = _to_tm_wday(data[LPTIME_WDAY]); |
| alarm->enabled = data[LPTIME_WDAY] & LP8788_ALM_EN_M; |
| |
| return 0; |
| } |
| |
| static int lp8788_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) |
| { |
| struct lp8788_rtc *rtc = dev_get_drvdata(dev); |
| struct lp8788 *lp = rtc->lp; |
| struct rtc_time *tm = &alarm->time; |
| u8 addr, data[LPTIME_MAX]; |
| int ret, i, year; |
| |
| year = tm->tm_year + 1900 - LP8788_BASE_YEAR; |
| if (year < 0) { |
| dev_err(lp->dev, "invalid year: %d\n", year); |
| return -EINVAL; |
| } |
| |
| data[LPTIME_SEC] = tm->tm_sec; |
| data[LPTIME_MIN] = tm->tm_min; |
| data[LPTIME_HOUR] = tm->tm_hour; |
| data[LPTIME_MDAY] = tm->tm_mday; |
| data[LPTIME_MON] = tm->tm_mon + LP8788_MONTH_OFFSET; |
| data[LPTIME_YEAR] = year; |
| data[LPTIME_WDAY] = _to_lp8788_wday(tm->tm_wday); |
| |
| for (i = 0; i < ARRAY_SIZE(data); i++) { |
| addr = addr_alarm_sec[rtc->alarm] + i; |
| ret = lp8788_write_byte(lp, addr, data[i]); |
| if (ret) |
| return ret; |
| } |
| |
| alarm->enabled = 1; |
| addr = addr_alarm_en[rtc->alarm]; |
| |
| return lp8788_update_bits(lp, addr, LP8788_ALM_EN_M, |
| alarm->enabled << LP8788_ALM_EN_S); |
| } |
| |
| static int lp8788_alarm_irq_enable(struct device *dev, unsigned int enable) |
| { |
| struct lp8788_rtc *rtc = dev_get_drvdata(dev); |
| struct lp8788 *lp = rtc->lp; |
| u8 mask, shift; |
| |
| if (!rtc->irq) |
| return -EIO; |
| |
| mask = mask_alarm_en[rtc->alarm]; |
| shift = shift_alarm_en[rtc->alarm]; |
| |
| return lp8788_update_bits(lp, LP8788_INTEN_3, mask, enable << shift); |
| } |
| |
| static const struct rtc_class_ops lp8788_rtc_ops = { |
| .read_time = lp8788_rtc_read_time, |
| .set_time = lp8788_rtc_set_time, |
| .read_alarm = lp8788_read_alarm, |
| .set_alarm = lp8788_set_alarm, |
| .alarm_irq_enable = lp8788_alarm_irq_enable, |
| }; |
| |
| static irqreturn_t lp8788_alarm_irq_handler(int irq, void *ptr) |
| { |
| struct lp8788_rtc *rtc = ptr; |
| |
| rtc_update_irq(rtc->rdev, 1, ALARM_IRQ_FLAG); |
| return IRQ_HANDLED; |
| } |
| |
| static int lp8788_alarm_irq_register(struct platform_device *pdev, |
| struct lp8788_rtc *rtc) |
| { |
| struct resource *r; |
| struct lp8788 *lp = rtc->lp; |
| struct irq_domain *irqdm = lp->irqdm; |
| int irq; |
| |
| rtc->irq = 0; |
| |
| /* even the alarm IRQ number is not specified, rtc time should work */ |
| r = platform_get_resource_byname(pdev, IORESOURCE_IRQ, LP8788_ALM_IRQ); |
| if (!r) |
| return 0; |
| |
| if (rtc->alarm == LP8788_ALARM_1) |
| irq = r->start; |
| else |
| irq = r->end; |
| |
| rtc->irq = irq_create_mapping(irqdm, irq); |
| |
| return devm_request_threaded_irq(&pdev->dev, rtc->irq, NULL, |
| lp8788_alarm_irq_handler, |
| 0, LP8788_ALM_IRQ, rtc); |
| } |
| |
| static int lp8788_rtc_probe(struct platform_device *pdev) |
| { |
| struct lp8788 *lp = dev_get_drvdata(pdev->dev.parent); |
| struct lp8788_rtc *rtc; |
| struct device *dev = &pdev->dev; |
| |
| rtc = devm_kzalloc(dev, sizeof(struct lp8788_rtc), GFP_KERNEL); |
| if (!rtc) |
| return -ENOMEM; |
| |
| rtc->lp = lp; |
| rtc->alarm = lp->pdata ? lp->pdata->alarm_sel : DEFAULT_ALARM_SEL; |
| platform_set_drvdata(pdev, rtc); |
| |
| device_init_wakeup(dev, 1); |
| |
| rtc->rdev = devm_rtc_device_register(dev, "lp8788_rtc", |
| &lp8788_rtc_ops, THIS_MODULE); |
| if (IS_ERR(rtc->rdev)) { |
| dev_err(dev, "can not register rtc device\n"); |
| return PTR_ERR(rtc->rdev); |
| } |
| |
| if (lp8788_alarm_irq_register(pdev, rtc)) |
| dev_warn(lp->dev, "no rtc irq handler\n"); |
| |
| return 0; |
| } |
| |
| static struct platform_driver lp8788_rtc_driver = { |
| .probe = lp8788_rtc_probe, |
| .driver = { |
| .name = LP8788_DEV_RTC, |
| }, |
| }; |
| module_platform_driver(lp8788_rtc_driver); |
| |
| MODULE_DESCRIPTION("Texas Instruments LP8788 RTC Driver"); |
| MODULE_AUTHOR("Milo Kim"); |
| MODULE_LICENSE("GPL"); |
| MODULE_ALIAS("platform:lp8788-rtc"); |