Hi, On 07/11/2017 at 19:34:08 +0800, Baolin Wang wrote: > This patch adds the Spreadtrum RTC driver, which embedded in the > Spreadtrum SC27xx PMIC series. > > Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxx> > --- > drivers/rtc/Kconfig | 7 + > drivers/rtc/Makefile | 1 + > drivers/rtc/rtc-sprd.c | 673 ++++++++++++++++++++++++++++++++++++++++++++++++ I would prefer that filename to be more specific. What if at some point one of your SoC includes an RTC that is not handled by this driver. This will become a naming nightmare. > 3 files changed, 681 insertions(+) > create mode 100644 drivers/rtc/rtc-sprd.c > > diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig > index e0e58f3..c3059fa 100644 > --- a/drivers/rtc/Kconfig > +++ b/drivers/rtc/Kconfig > @@ -1182,6 +1182,13 @@ config RTC_DRV_SPEAR > If you say Y here you will get support for the RTC found on > spear > > +config RTC_DRV_SPRD > + tristate "Spreadtrum SC27xx RTC" > + depends on ARCH_SPRD || COMPILE_TEST the commit message says this is a PMIC RTC, not a SoC RTC. I don't think you need to depend on ARCH_SPRD. But you probably need to depend on the MFD parent. > + help > + If you say Y here you will get support for the RTC found on > + Spreadtrum. Be mor precise here. > + > config RTC_DRV_PCF50633 > depends on MFD_PCF50633 > tristate "NXP PCF50633 RTC" > diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile > index 7230014..ec5cb75 100644 > --- a/drivers/rtc/Makefile > +++ b/drivers/rtc/Makefile > @@ -147,6 +147,7 @@ obj-$(CONFIG_RTC_DRV_SH) += rtc-sh.o > obj-$(CONFIG_RTC_DRV_SIRFSOC) += rtc-sirfsoc.o > obj-$(CONFIG_RTC_DRV_SNVS) += rtc-snvs.o > obj-$(CONFIG_RTC_DRV_SPEAR) += rtc-spear.o > +obj-$(CONFIG_RTC_DRV_SPRD) += rtc-sprd.o > obj-$(CONFIG_RTC_DRV_STARFIRE) += rtc-starfire.o > obj-$(CONFIG_RTC_DRV_STK17TA8) += rtc-stk17ta8.o > obj-$(CONFIG_RTC_DRV_STM32) += rtc-stm32.o > diff --git a/drivers/rtc/rtc-sprd.c b/drivers/rtc/rtc-sprd.c > new file mode 100644 > index 0000000..6b2477f > --- /dev/null > +++ b/drivers/rtc/rtc-sprd.c > @@ -0,0 +1,673 @@ > +/* > + * Copyright (C) 2017 Spreadtrum Communications Inc. > + * > + * SPDX-License-Identifier: GPL-2.0 > + */ > + > +#include <linux/bitops.h> > +#include <linux/delay.h> > +#include <linux/err.h> > +#include <linux/module.h> > +#include <linux/of.h> > +#include <linux/platform_device.h> > +#include <linux/regmap.h> > +#include <linux/rtc.h> > + > +#define SPRD_RTC_SEC_CNT_VALUE 0x0 > +#define SPRD_RTC_MIN_CNT_VALUE 0x4 > +#define SPRD_RTC_HOUR_CNT_VALUE 0x8 > +#define SPRD_RTC_DAY_CNT_VALUE 0xc > +#define SPRD_RTC_SEC_CNT_UPD 0x10 > +#define SPRD_RTC_MIN_CNT_UPD 0x14 > +#define SPRD_RTC_HOUR_CNT_UPD 0x18 > +#define SPRD_RTC_DAY_CNT_UPD 0x1c > +#define SPRD_RTC_SEC_ALM_UPD 0x20 > +#define SPRD_RTC_MIN_ALM_UPD 0x24 > +#define SPRD_RTC_HOUR_ALM_UPD 0x28 > +#define SPRD_RTC_DAY_ALM_UPD 0x2c > +#define SPRD_RTC_INT_EN 0x30 > +#define SPRD_RTC_INT_RAW_STS 0x34 > +#define SPRD_RTC_INT_CLR 0x38 > +#define SPRD_RTC_INT_MASK_STS 0x3C > +#define SPRD_RTC_SEC_ALM_VALUE 0x40 > +#define SPRD_RTC_MIN_ALM_VALUE 0x44 > +#define SPRD_RTC_HOUR_ALM_VALUE 0x48 > +#define SPRD_RTC_DAY_ALM_VALUE 0x4c > +#define SPRD_RTC_SPG_VALUE 0x50 > +#define SPRD_RTC_SPG_UPD 0x54 > +#define SPRD_RTC_SEC_AUXALM_UPD 0x60 > +#define SPRD_RTC_MIN_AUXALM_UPD 0x64 > +#define SPRD_RTC_HOUR_AUXALM_UPD 0x68 > +#define SPRD_RTC_DAY_AUXALM_UPD 0x6c > + > +/* BIT & MASK definition for SPRD_RTC_INT_* registers */ > +#define SPRD_RTC_SEC_EN BIT(0) > +#define SPRD_RTC_MIN_EN BIT(1) > +#define SPRD_RTC_HOUR_EN BIT(2) > +#define SPRD_RTC_DAY_EN BIT(3) > +#define SPRD_RTC_ALARM_EN BIT(4) > +#define SPRD_RTC_HRS_FORMAT_EN BIT(5) > +#define SPRD_RTC_AUXALM_EN BIT(6) > +#define SPRD_RTC_SPG_UPD_EN BIT(7) > +#define SPRD_RTC_SEC_UPD_EN BIT(8) > +#define SPRD_RTC_MIN_UPD_EN BIT(9) > +#define SPRD_RTC_HOUR_UPD_EN BIT(10) > +#define SPRD_RTC_DAY_UPD_EN BIT(11) > +#define SPRD_RTC_ALMSEC_UPD_EN BIT(12) > +#define SPRD_RTC_ALMMIN_UPD_EN BIT(13) > +#define SPRD_RTC_ALMHOUR_UPD_EN BIT(14) > +#define SPRD_RTC_ALMDAY_UPD_EN BIT(15) > +#define SPRD_RTC_INT_MASK GENMASK(15, 0) > + > +#define SPRD_RTC_TIME_INT_MASK \ > + (SPRD_RTC_SEC_UPD_EN | SPRD_RTC_MIN_UPD_EN | \ > + SPRD_RTC_HOUR_UPD_EN | SPRD_RTC_DAY_UPD_EN) > + > +#define SPRD_RTC_ALMTIME_INT_MASK \ > + (SPRD_RTC_ALMSEC_UPD_EN | SPRD_RTC_ALMMIN_UPD_EN | \ > + SPRD_RTC_ALMHOUR_UPD_EN | SPRD_RTC_ALMDAY_UPD_EN) > + > +#define SPRD_RTC_ALM_INT_MASK \ > + (SPRD_RTC_SEC_EN | SPRD_RTC_MIN_EN | \ > + SPRD_RTC_HOUR_EN | SPRD_RTC_DAY_EN | \ > + SPRD_RTC_ALARM_EN | SPRD_RTC_AUXALM_EN) > + > +/* second/minute/hour/day values mask definition */ > +#define SPRD_RTC_SEC_MASK GENMASK(5, 0) > +#define SPRD_RTC_MIN_MASK GENMASK(5, 0) > +#define SPRD_RTC_HOUR_MASK GENMASK(4, 0) > +#define SPRD_RTC_DAY_MASK GENMASK(15, 0) > + > +/* alarm lock definition for SPRD_RTC_SPG_UPD register */ > +#define SPRD_RTC_ALMLOCK_MASK GENMASK(7, 0) > +#define SPRD_RTC_ALM_UNLOCK 0xa5 > +#define SPRD_RTC_ALM_LOCK (~SPRD_RTC_ALM_UNLOCK & SPRD_RTC_ALMLOCK_MASK) > + > +/* SPG values definition for SPRD_RTC_SPG_UPD register */ > +#define SPRD_RTC_POWEROFF_ALM_FLAG BIT(8) > +#define SPRD_RTC_POWER_RESET_FLAG BIT(9) > + > +/* timeout of synchronizing time and alarm registers (us) */ > +#define SPRD_RTC_POLL_TIMEOUT 200000 > +#define SPRD_RTC_POLL_DELAY_US 20000 > +#define SPRD_RTC_START_YEAR 2017 > + > +struct sprd_rtc { > + struct rtc_device *rtc; > + struct regmap *regmap; > + struct device *dev; > + u32 base; > + int irq; > +}; > + > +/* > + * The Spreadtrum RTC controller has 3 groups registers, including time, normal > + * alarm and auxiliary alarm. The time group registers are used to set RTC time, > + * the normal alarm registers are used to set normal alarm, and the auxiliary > + * alarm registers are used to set auxiliary alarm. Both alarm event and > + * auxiliary alarm event can wake up system from deep sleep, but only alarm > + * event can power up system from power down status. > + */ > +enum sprd_rtc_reg_types { > + SPRD_RTC_TIME, > + SPRD_RTC_ALARM, > + SPRD_RTC_AUX_ALARM, > +}; > + > +static int sprd_rtc_read(struct sprd_rtc *rtc, u32 reg, u32 *val) > +{ > + return regmap_read(rtc->regmap, rtc->base + reg, val); > +} > + > +static int sprd_rtc_write(struct sprd_rtc *rtc, u32 reg, u32 val) > +{ > + return regmap_write(rtc->regmap, rtc->base + reg, val); > +} > + > +static int sprd_rtc_update(struct sprd_rtc *rtc, u32 reg, u32 mask, u32 val) > +{ > + return regmap_update_bits(rtc->regmap, rtc->base + reg, mask, val); > +} > + > +static int sprd_rtc_read_poll(struct sprd_rtc *rtc, u32 reg, u32 mask) > +{ > + u32 val; > + > + return regmap_read_poll_timeout(rtc->regmap, rtc->base + reg, val, > + ((val & mask) == mask), > + SPRD_RTC_POLL_DELAY_US, > + SPRD_RTC_POLL_TIMEOUT); > +} > + All those functions are only wrappers around regmap, they are useless, please use regmap_* directly. > +static int sprd_rtc_clear_alarm_ints(struct sprd_rtc *rtc) > +{ > + return sprd_rtc_write(rtc, SPRD_RTC_INT_CLR, SPRD_RTC_ALM_INT_MASK); > +} > + > +static int sprd_rtc_disable_ints(struct sprd_rtc *rtc) > +{ > + int ret; > + > + ret = sprd_rtc_update(rtc, SPRD_RTC_INT_EN, SPRD_RTC_INT_MASK, 0); > + if (ret) > + return ret; > + > + return sprd_rtc_write(rtc, SPRD_RTC_INT_CLR, SPRD_RTC_INT_MASK); > +} > + > +static int sprd_rtc_lock_alarm(struct sprd_rtc *rtc) > +{ > + int ret; > + u32 val; > + > + ret = sprd_rtc_read(rtc, SPRD_RTC_SPG_VALUE, &val); > + if (ret) > + return ret; > + > + val &= ~(SPRD_RTC_ALMLOCK_MASK | SPRD_RTC_POWEROFF_ALM_FLAG); > + val |= SPRD_RTC_ALM_LOCK; > + return sprd_rtc_write(rtc, SPRD_RTC_SPG_UPD, val); > +} > + > +static int sprd_rtc_unlock_alarm(struct sprd_rtc *rtc) > +{ > + int ret; > + u32 val; > + > + ret = sprd_rtc_read(rtc, SPRD_RTC_SPG_VALUE, &val); > + if (ret) > + return ret; > + > + val &= ~(SPRD_RTC_ALMLOCK_MASK | SPRD_RTC_POWEROFF_ALM_FLAG); > + val |= SPRD_RTC_ALM_UNLOCK | SPRD_RTC_POWEROFF_ALM_FLAG; > + return sprd_rtc_write(rtc, SPRD_RTC_SPG_UPD, val); > +} > + > +static int sprd_rtc_get_secs(struct sprd_rtc *rtc, enum sprd_rtc_reg_types type, > + time64_t *secs) > +{ > + u32 sec_reg, min_reg, hour_reg, day_reg; > + u32 val, sec, min, hour, day; > + int ret; > + > + switch (type) { > + case SPRD_RTC_TIME: > + sec_reg = SPRD_RTC_SEC_CNT_VALUE; > + min_reg = SPRD_RTC_MIN_CNT_VALUE; > + hour_reg = SPRD_RTC_HOUR_CNT_VALUE; > + day_reg = SPRD_RTC_DAY_CNT_VALUE; > + break; > + case SPRD_RTC_ALARM: > + sec_reg = SPRD_RTC_SEC_ALM_VALUE; > + min_reg = SPRD_RTC_MIN_ALM_VALUE; > + hour_reg = SPRD_RTC_HOUR_ALM_VALUE; > + day_reg = SPRD_RTC_DAY_ALM_VALUE; > + break; > + case SPRD_RTC_AUX_ALARM: > + sec_reg = SPRD_RTC_SEC_AUXALM_UPD; > + min_reg = SPRD_RTC_MIN_AUXALM_UPD; > + hour_reg = SPRD_RTC_HOUR_AUXALM_UPD; > + day_reg = SPRD_RTC_DAY_AUXALM_UPD; > + break; > + default: > + return -EINVAL; > + } > + > + ret = sprd_rtc_read(rtc, sec_reg, &val); > + if (ret) > + return ret; > + > + sec = val & SPRD_RTC_SEC_MASK; > + > + ret = sprd_rtc_read(rtc, min_reg, &val); > + if (ret) > + return ret; > + > + min = val & SPRD_RTC_MIN_MASK; > + > + ret = sprd_rtc_read(rtc, hour_reg, &val); > + if (ret) > + return ret; > + > + hour = val & SPRD_RTC_HOUR_MASK; > + > + ret = sprd_rtc_read(rtc, day_reg, &val); > + if (ret) > + return ret; > + > + day = val & SPRD_RTC_DAY_MASK; > + *secs = (((time64_t)(day * 24) + hour) * 60 + min) * 60 + sec; > + return 0; > +} > + > +static int sprd_rtc_set_secs(struct sprd_rtc *rtc, enum sprd_rtc_reg_types type, > + time64_t secs) > +{ > + u32 sec_reg, min_reg, hour_reg, day_reg, sts_mask; > + u32 sec, min, hour, day; > + int ret, rem; > + > + /* convert seconds to RTC time format */ > + day = div_s64_rem(secs, 86400, &rem); > + hour = rem / 3600; > + rem -= hour * 3600; > + min = rem / 60; > + sec = rem - min * 60; > + > + switch (type) { > + case SPRD_RTC_TIME: > + sec_reg = SPRD_RTC_SEC_CNT_UPD; > + min_reg = SPRD_RTC_MIN_CNT_UPD; > + hour_reg = SPRD_RTC_HOUR_CNT_UPD; > + day_reg = SPRD_RTC_DAY_CNT_UPD; > + sts_mask = SPRD_RTC_TIME_INT_MASK; > + break; > + case SPRD_RTC_ALARM: > + sec_reg = SPRD_RTC_SEC_ALM_UPD; > + min_reg = SPRD_RTC_MIN_ALM_UPD; > + hour_reg = SPRD_RTC_HOUR_ALM_UPD; > + day_reg = SPRD_RTC_DAY_ALM_UPD; > + sts_mask = SPRD_RTC_ALMTIME_INT_MASK; > + break; > + case SPRD_RTC_AUX_ALARM: > + sec_reg = SPRD_RTC_SEC_AUXALM_UPD; > + min_reg = SPRD_RTC_MIN_AUXALM_UPD; > + hour_reg = SPRD_RTC_HOUR_AUXALM_UPD; > + day_reg = SPRD_RTC_DAY_AUXALM_UPD; > + sts_mask = 0; > + break; > + default: > + return -EINVAL; > + } > + > + ret = sprd_rtc_write(rtc, sec_reg, sec); > + if (ret) > + return ret; > + > + ret = sprd_rtc_write(rtc, min_reg, min); > + if (ret) > + return ret; > + > + ret = sprd_rtc_write(rtc, hour_reg, hour); > + if (ret) > + return ret; > + > + ret = sprd_rtc_write(rtc, day_reg, day); > + if (ret) > + return ret; > + > + if (type == SPRD_RTC_AUX_ALARM) > + return 0; > + > + /* > + * Since the time and normal alarm registers are put in always-power-on > + * region supplied by VDDRTC, then these registers changing time will > + * be very long, about 125ms. Thus here we should wait until all > + * values are updated successfully. > + */ > + ret = sprd_rtc_read_poll(rtc, SPRD_RTC_INT_RAW_STS, sts_mask); > + if (ret < 0) { > + dev_err(rtc->dev, "set time/alarm values timeout\n"); > + return ret; > + } > + > + return sprd_rtc_write(rtc, SPRD_RTC_INT_CLR, sts_mask); > +} > + > +static int sprd_rtc_read_aux_alarm(struct device *dev, struct rtc_wkalrm *alrm) > +{ > + struct sprd_rtc *rtc = dev_get_drvdata(dev); > + time64_t secs; > + u32 val; > + int ret; > + > + ret = sprd_rtc_get_secs(rtc, SPRD_RTC_AUX_ALARM, &secs); > + if (ret) > + return ret; > + > + rtc_time64_to_tm(secs, &alrm->time); > + > + ret = sprd_rtc_read(rtc, SPRD_RTC_INT_EN, &val); > + if (ret) > + return ret; > + > + alrm->enabled = !!(val & SPRD_RTC_AUXALM_EN); > + > + ret = sprd_rtc_read(rtc, SPRD_RTC_INT_RAW_STS, &val); > + if (ret) > + return ret; > + > + alrm->pending = !!(val & SPRD_RTC_AUXALM_EN); > + return 0; > +} > + > +static int sprd_rtc_set_aux_alarm(struct device *dev, struct rtc_wkalrm *alrm) > +{ > + struct sprd_rtc *rtc = dev_get_drvdata(dev); > + int ret; > + > + /* clear the auxiliary alarm interrupt status */ > + ret = sprd_rtc_write(rtc, SPRD_RTC_INT_CLR, SPRD_RTC_AUXALM_EN); > + if (ret) > + return ret; > + > + if (alrm->enabled) { > + time64_t secs = rtc_tm_to_time64(&alrm->time); > + > + /* enable the auxiliary alarm interrupt */ > + ret = sprd_rtc_update(rtc, SPRD_RTC_INT_EN, SPRD_RTC_AUXALM_EN, > + SPRD_RTC_AUXALM_EN); > + if (ret) > + return ret; > + > + ret = sprd_rtc_set_secs(rtc, SPRD_RTC_AUX_ALARM, secs); > + if (ret) { > + sprd_rtc_update(rtc, SPRD_RTC_INT_EN, > + SPRD_RTC_AUXALM_EN, 0); > + } > + } else { > + /* disable the auxiliary alarm interrupt */ > + ret = sprd_rtc_update(rtc, SPRD_RTC_INT_EN, > + SPRD_RTC_AUXALM_EN, 0); This is not setting the alarm registers properly. What if the alarm is enabled at a later time by sprd_rtc_alarm_irq_enable()? > + } > + > + return ret; > +} > + > +static int sprd_rtc_read_time(struct device *dev, struct rtc_time *tm) > +{ > + struct sprd_rtc *rtc = dev_get_drvdata(dev); > + time64_t secs; > + int ret; > + > + ret = sprd_rtc_get_secs(rtc, SPRD_RTC_TIME, &secs); > + if (ret) > + return ret; > + > + rtc_time64_to_tm(secs, tm); > + return rtc_valid_tm(tm); > +} > + > +static int sprd_rtc_set_time(struct device *dev, struct rtc_time *tm) > +{ > + struct sprd_rtc *rtc = dev_get_drvdata(dev); > + time64_t secs = rtc_tm_to_time64(tm); > + > + return sprd_rtc_set_secs(rtc, SPRD_RTC_TIME, secs); > +} > + > +static int sprd_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) > +{ > + struct sprd_rtc *rtc = dev_get_drvdata(dev); > + time64_t secs; > + int ret; > + u32 val; > + > + /* > + * If aie_timer is enabled, we should get the normal alarm time. > + * Otherwise we should get auxiliary alarm time. > + */ > + if (rtc->rtc && rtc->rtc->aie_timer.enabled == 0) > + return sprd_rtc_read_aux_alarm(dev, alrm); > + > + ret = sprd_rtc_get_secs(rtc, SPRD_RTC_ALARM, &secs); > + if (ret) > + return ret; > + > + rtc_time64_to_tm(secs, &alrm->time); > + > + ret = sprd_rtc_read(rtc, SPRD_RTC_INT_EN, &val); > + if (ret) > + return ret; > + > + alrm->enabled = !!(val & SPRD_RTC_ALARM_EN); > + > + ret = sprd_rtc_read(rtc, SPRD_RTC_INT_RAW_STS, &val); > + if (ret) > + return ret; > + > + alrm->pending = !!(val & SPRD_RTC_ALARM_EN); > + return 0; > +} > + > +static int sprd_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) > +{ > + struct sprd_rtc *rtc = dev_get_drvdata(dev); > + struct rtc_time aie_time = > + rtc_ktime_to_tm(rtc->rtc->aie_timer.node.expires); > + int ret; > + > + /* > + * We have 2 groups alarms: normal alarm and auxiliary alarm. Since > + * both normal alarm event and auxiliary alarm event can wake up system > + * from deep sleep, but only alarm event can power up system from power > + * down status. Moreover we do not need to poll about 125ms when > + * updating auxiliary alarm registers. Thus we usually set auxiliary > + * alarm when wake up system from deep sleep, and for other scenarios, > + * we should set normal alarm with polling status. > + * > + * So here we check if the alarm time is set by aie_timer, if yes, we > + * should set normal alarm, if not, we should set auxiliary alarm which > + * means it is just a wake event. > + */ > + if (!rtc->rtc->aie_timer.enabled || rtc_tm_sub(&aie_time, &alrm->time)) > + return sprd_rtc_set_aux_alarm(dev, alrm); > + > + /* clear the alarm interrupt status firstly */ > + ret = sprd_rtc_write(rtc, SPRD_RTC_INT_CLR, SPRD_RTC_ALARM_EN); > + if (ret) > + return ret; > + > + if (alrm->enabled) { > + time64_t secs = rtc_tm_to_time64(&alrm->time); > + > + /* enable the alarm interrupt */ > + ret = sprd_rtc_update(rtc, SPRD_RTC_INT_EN, SPRD_RTC_ALARM_EN, > + SPRD_RTC_ALARM_EN); > + if (ret) > + return ret; > + > + ret = sprd_rtc_set_secs(rtc, SPRD_RTC_ALARM, secs); > + if (ret) > + goto err; > + > + /* unlock the alarm to enable the alarm function. */ > + ret = sprd_rtc_unlock_alarm(rtc); > + if (ret) > + goto err; > + } else { ditto. > + /* disable the alarm interrupt */ > + ret = sprd_rtc_update(rtc, SPRD_RTC_INT_EN, > + SPRD_RTC_ALARM_EN, 0); > + if (ret) > + return ret; > + > + /* > + * Lock the alarm function in case fake alarm event will power > + * up systems. > + */ > + ret = sprd_rtc_lock_alarm(rtc); > + } > + > + return ret; > + > +err: > + sprd_rtc_update(rtc, SPRD_RTC_INT_EN, SPRD_RTC_ALARM_EN, 0); > + return ret; > +} > + > +static int sprd_rtc_set_mmss(struct device *dev, time64_t secs) > +{ > + struct sprd_rtc *rtc = dev_get_drvdata(dev); > + > + return sprd_rtc_set_secs(rtc, SPRD_RTC_TIME, secs); > +} Because set_time is defined, this function will never be called, please remove it. > + > +static int sprd_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) > +{ > + struct sprd_rtc *rtc = dev_get_drvdata(dev); > + > + if (enabled) { > + return sprd_rtc_update(rtc, SPRD_RTC_INT_EN, > + SPRD_RTC_ALARM_EN | SPRD_RTC_AUXALM_EN, > + SPRD_RTC_ALARM_EN | SPRD_RTC_AUXALM_EN); > + } else { > + return sprd_rtc_update(rtc, SPRD_RTC_INT_EN, > + SPRD_RTC_ALARM_EN | SPRD_RTC_AUXALM_EN, > + 0); > + } > +} > + > +static const struct rtc_class_ops sprd_rtc_ops = { > + .read_time = sprd_rtc_read_time, > + .set_time = sprd_rtc_set_time, > + .read_alarm = sprd_rtc_read_alarm, > + .set_alarm = sprd_rtc_set_alarm, > + .set_mmss64 = sprd_rtc_set_mmss, > + .alarm_irq_enable = sprd_rtc_alarm_irq_enable, > +}; > + > +static irqreturn_t sprd_rtc_handler(int irq, void *dev_id) > +{ > + struct sprd_rtc *rtc = dev_id; > + int ret; > + > + ret = sprd_rtc_clear_alarm_ints(rtc); > + if (ret) > + return IRQ_RETVAL(ret); > + > + rtc_update_irq(rtc->rtc, 1, RTC_AF | RTC_IRQF); > + return IRQ_HANDLED; > +} > + > +static int sprd_rtc_init_time(struct sprd_rtc *rtc) > +{ > + time64_t secs = mktime64(SPRD_RTC_START_YEAR, 1, 1, 0, 0, 0); > + > + dev_dbg(rtc->dev, "RTC power down and reset time.\n"); > + return sprd_rtc_set_secs(rtc, SPRD_RTC_TIME, secs); > +} > + > +static int sprd_rtc_check_power_down(struct sprd_rtc *rtc) > +{ > + int ret; > + u32 val; > + > + ret = sprd_rtc_read(rtc, SPRD_RTC_SPG_VALUE, &val); > + if (ret) > + return ret; > + > + if (val & SPRD_RTC_POWER_RESET_FLAG) > + return 0; > + > + ret = sprd_rtc_init_time(rtc); Don't do that. This is a valuable information. If you know the time is invalid, return -EINVAL in read_time(). What your are doing here is confusing the system by making it believe your fake date is the correct time. > + if (ret < 0) { > + dev_err(rtc->dev, "failed to initialize RTC time\n"); > + return ret; > + } > + > + val |= SPRD_RTC_POWER_RESET_FLAG; > + ret = sprd_rtc_write(rtc, SPRD_RTC_SPG_UPD, val); > + if (ret) > + return ret; > + > + /* wait until the SPG value is updated successfully */ > + ret = sprd_rtc_read_poll(rtc, SPRD_RTC_INT_RAW_STS, > + SPRD_RTC_SPG_UPD_EN); > + if (ret < 0) { > + dev_err(rtc->dev, "failed to update SPG value\n"); > + return ret; > + } > + > + return 0; > +} > + > +static int sprd_rtc_probe(struct platform_device *pdev) > +{ > + struct device_node *node = pdev->dev.of_node; > + struct sprd_rtc *rtc; > + int ret; > + > + rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL); > + if (!rtc) > + return -ENOMEM; > + > + rtc->regmap = dev_get_regmap(pdev->dev.parent, NULL); > + if (!rtc->regmap) > + return -ENODEV; > + > + ret = of_property_read_u32(node, "reg", &rtc->base); > + if (ret) { > + dev_err(&pdev->dev, "failed to get RTC base address\n"); > + return ret; > + } > + > + rtc->irq = platform_get_irq(pdev, 0); > + if (rtc->irq < 0) { > + dev_err(&pdev->dev, "failed to get RTC irq number\n"); > + return rtc->irq; > + } > + > + rtc->dev = &pdev->dev; > + platform_set_drvdata(pdev, rtc); > + > + /* Clear all RTC interrupts and disable all RTC interrupts */ > + ret = sprd_rtc_disable_ints(rtc); > + if (ret) { > + dev_err(&pdev->dev, "failed to disable RTC interrupts\n"); > + return ret; > + } > + > + /* > + * Check if RTC has been powered down, if so, we should reset RTC > + * time to avoid uncertain values in RTC registers. > + */ > + ret = sprd_rtc_check_power_down(rtc); > + if (ret) { > + dev_err(&pdev->dev, "failed to check RTC power\n"); > + return ret; > + } > + > + ret = devm_request_threaded_irq(&pdev->dev, rtc->irq, NULL, > + sprd_rtc_handler, > + IRQF_ONESHOT | IRQF_EARLY_RESUME, > + pdev->name, rtc); > + if (ret < 0) { > + dev_err(&pdev->dev, "failed to request RTC irq\n"); > + return ret; > + } > + > + rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name, > + &sprd_rtc_ops, THIS_MODULE); > + if (IS_ERR(rtc->rtc)) > + return PTR_ERR(rtc->rtc); > + > + device_init_wakeup(&pdev->dev, 1); > + return 0; > +} > + > +static int sprd_rtc_remove(struct platform_device *pdev) > +{ > + device_init_wakeup(&pdev->dev, 0); > + return 0; > +} > + > +static const struct of_device_id sprd_rtc_of_match[] = { > + { .compatible = "sprd,sc27xx-rtc", }, > + { }, > +}; > +MODULE_DEVICE_TABLE(of, sprd_rtc_of_match); > + > +static struct platform_driver sprd_rtc_driver = { > + .driver = { > + .name = "sprd-rtc", > + .of_match_table = sprd_rtc_of_match, > + }, > + .probe = sprd_rtc_probe, > + .remove = sprd_rtc_remove, > +}; > +module_platform_driver(sprd_rtc_driver); > + > +MODULE_LICENSE("GPL v2"); > +MODULE_DESCRIPTION("Spreadtrum RTC Device Driver"); > +MODULE_AUTHOR("Baolin Wang <baolin.wang@xxxxxxxxxxxxxx>"); > -- > 1.7.9.5 > -- Alexandre Belloni, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html