From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933128AbdKGLjp (ORCPT ); Tue, 7 Nov 2017 06:39:45 -0500 Received: from sci-ig2.spreadtrum.com ([222.66.158.135]:14366 "EHLO SHSQR01.spreadtrum.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1756164AbdKGLjm (ORCPT ); Tue, 7 Nov 2017 06:39:42 -0500 From: Baolin Wang To: , , , CC: , , , , , Subject: [PATCH 2/2] rtc: sprd: Add Spreadtrum RTC driver Date: Tue, 7 Nov 2017 19:34:08 +0800 Message-ID: X-Mailer: git-send-email 2.12.2 In-Reply-To: <7037c5053a533505f38fc036290a398989cfdafc.1510051749.git.baolin.wang@spreadtrum.com> References: <7037c5053a533505f38fc036290a398989cfdafc.1510051749.git.baolin.wang@spreadtrum.com> MIME-Version: 1.0 Content-Type: text/plain X-MAIL: SHSQR01.spreadtrum.com vA7Bd8R3022935 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch adds the Spreadtrum RTC driver, which embedded in the Spreadtrum SC27xx PMIC series. Signed-off-by: Baolin Wang --- drivers/rtc/Kconfig | 7 + drivers/rtc/Makefile | 1 + drivers/rtc/rtc-sprd.c | 673 ++++++++++++++++++++++++++++++++++++++++++++++++ 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 + help + If you say Y here you will get support for the RTC found on + Spreadtrum. + 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 +#include +#include +#include +#include +#include +#include +#include + +#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); +} + +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); + } + + 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 { + /* 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); +} + +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); + 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 "); -- 1.7.9.5