// SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2017 Spreadtrum Communications Inc. * */ #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_PWR_CTRL 0x58 #define SPRD_RTC_PWR_STS 0x5c #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) /* power control/status definition */ #define SPRD_RTC_POWER_RESET_VALUE 0x96 #define SPRD_RTC_POWER_STS_CLEAR GENMASK(7, 0) #define SPRD_RTC_POWER_STS_SHIFT 8 #define SPRD_RTC_POWER_STS_VALID \ (~SPRD_RTC_POWER_RESET_VALUE << SPRD_RTC_POWER_STS_SHIFT) /* timeout of synchronizing time and alarm registers (us) */ #define SPRD_RTC_POLL_TIMEOUT 200000 #define SPRD_RTC_POLL_DELAY_US 20000 struct sprd_rtc { struct rtc_device *rtc; struct regmap *regmap; struct device *dev; u32 base; int irq; bool valid; }; /* * 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_clear_alarm_ints(struct sprd_rtc *rtc) { return regmap_write(rtc->regmap, rtc->base + SPRD_RTC_INT_CLR, SPRD_RTC_ALM_INT_MASK); } static int sprd_rtc_lock_alarm(struct sprd_rtc *rtc, bool lock) { int ret; u32 val; ret = regmap_read(rtc->regmap, rtc->base + SPRD_RTC_SPG_VALUE, &val); if (ret) return ret; val &= ~SPRD_RTC_ALMLOCK_MASK; if (lock) val |= SPRD_RTC_ALM_LOCK; else val |= SPRD_RTC_ALM_UNLOCK | SPRD_RTC_POWEROFF_ALM_FLAG; ret = regmap_write(rtc->regmap, rtc->base + SPRD_RTC_SPG_UPD, val); if (ret) return ret; /* wait until the SPG value is updated successfully */ ret = regmap_read_poll_timeout(rtc->regmap, rtc->base + SPRD_RTC_INT_RAW_STS, val, (val & SPRD_RTC_SPG_UPD_EN), SPRD_RTC_POLL_DELAY_US, SPRD_RTC_POLL_TIMEOUT); if (ret) { dev_err(rtc->dev, "failed to update SPG value:%d\n", ret); return ret; } return regmap_write(rtc->regmap, rtc->base + SPRD_RTC_INT_CLR, SPRD_RTC_SPG_UPD_EN); } 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 = regmap_read(rtc->regmap, rtc->base + sec_reg, &val); if (ret) return ret; sec = val & SPRD_RTC_SEC_MASK; ret = regmap_read(rtc->regmap, rtc->base + min_reg, &val); if (ret) return ret; min = val & SPRD_RTC_MIN_MASK; ret = regmap_read(rtc->regmap, rtc->base + hour_reg, &val); if (ret) return ret; hour = val & SPRD_RTC_HOUR_MASK; ret = regmap_read(rtc->regmap, rtc->base + 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, val; 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 = regmap_write(rtc->regmap, rtc->base + sec_reg, sec); if (ret) return ret; ret = regmap_write(rtc->regmap, rtc->base + min_reg, min); if (ret) return ret; ret = regmap_write(rtc->regmap, rtc->base + hour_reg, hour); if (ret) return ret; ret = regmap_write(rtc->regmap, rtc->base + 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 = regmap_read_poll_timeout(rtc->regmap, rtc->base + SPRD_RTC_INT_RAW_STS, val, ((val & sts_mask) == sts_mask), SPRD_RTC_POLL_DELAY_US, SPRD_RTC_POLL_TIMEOUT); if (ret < 0) { dev_err(rtc->dev, "set time/alarm values timeout\n"); return ret; } return regmap_write(rtc->regmap, rtc->base + SPRD_RTC_INT_CLR, sts_mask); } static int sprd_rtc_set_aux_alarm(struct device *dev, struct rtc_wkalrm *alrm) { struct sprd_rtc *rtc = dev_get_drvdata(dev); time64_t secs = rtc_tm_to_time64(&alrm->time); int ret; /* clear the auxiliary alarm interrupt status */ ret = regmap_write(rtc->regmap, rtc->base + SPRD_RTC_INT_CLR, SPRD_RTC_AUXALM_EN); if (ret) return ret; ret = sprd_rtc_set_secs(rtc, SPRD_RTC_AUX_ALARM, secs); if (ret) return ret; if (alrm->enabled) { ret = regmap_update_bits(rtc->regmap, rtc->base + SPRD_RTC_INT_EN, SPRD_RTC_AUXALM_EN, SPRD_RTC_AUXALM_EN); } else { ret = regmap_update_bits(rtc->regmap, rtc->base + 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; if (!rtc->valid) { dev_warn(dev, "RTC values are invalid\n"); return -EINVAL; } ret = sprd_rtc_get_secs(rtc, SPRD_RTC_TIME, &secs); if (ret) return ret; rtc_time64_to_tm(secs, tm); return 0; } 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); int ret; ret = sprd_rtc_set_secs(rtc, SPRD_RTC_TIME, secs); if (ret) return ret; if (!rtc->valid) { /* Clear RTC power status firstly */ ret = regmap_write(rtc->regmap, rtc->base + SPRD_RTC_PWR_CTRL, SPRD_RTC_POWER_STS_CLEAR); if (ret) return ret; /* * Set RTC power status to indicate now RTC has valid time * values. */ ret = regmap_write(rtc->regmap, rtc->base + SPRD_RTC_PWR_CTRL, SPRD_RTC_POWER_STS_VALID); if (ret) return ret; rtc->valid = true; } return 0; } 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; /* * The RTC core checks to see if there is an alarm already set in RTC * hardware, and we always read the normal alarm at this time. */ ret = sprd_rtc_get_secs(rtc, SPRD_RTC_ALARM, &secs); if (ret) return ret; rtc_time64_to_tm(secs, &alrm->time); ret = regmap_read(rtc->regmap, rtc->base + SPRD_RTC_INT_EN, &val); if (ret) return ret; alrm->enabled = !!(val & SPRD_RTC_ALARM_EN); ret = regmap_read(rtc->regmap, rtc->base + 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); time64_t secs = rtc_tm_to_time64(&alrm->time); 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 = regmap_write(rtc->regmap, rtc->base + SPRD_RTC_INT_CLR, SPRD_RTC_ALARM_EN); if (ret) return ret; ret = sprd_rtc_set_secs(rtc, SPRD_RTC_ALARM, secs); if (ret) return ret; if (alrm->enabled) { ret = regmap_update_bits(rtc->regmap, rtc->base + SPRD_RTC_INT_EN, SPRD_RTC_ALARM_EN, SPRD_RTC_ALARM_EN); if (ret) return ret; /* unlock the alarm to enable the alarm function. */ ret = sprd_rtc_lock_alarm(rtc, false); } else { regmap_update_bits(rtc->regmap, rtc->base + SPRD_RTC_INT_EN, SPRD_RTC_ALARM_EN, 0); /* * Lock the alarm function in case fake alarm event will power * up systems. */ ret = sprd_rtc_lock_alarm(rtc, true); } return ret; } static int sprd_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) { struct sprd_rtc *rtc = dev_get_drvdata(dev); int ret; if (enabled) { ret = regmap_update_bits(rtc->regmap, rtc->base + SPRD_RTC_INT_EN, SPRD_RTC_ALARM_EN | SPRD_RTC_AUXALM_EN, SPRD_RTC_ALARM_EN | SPRD_RTC_AUXALM_EN); if (ret) return ret; ret = sprd_rtc_lock_alarm(rtc, false); } else { regmap_update_bits(rtc->regmap, rtc->base + SPRD_RTC_INT_EN, SPRD_RTC_ALARM_EN | SPRD_RTC_AUXALM_EN, 0); ret = sprd_rtc_lock_alarm(rtc, true); } return ret; } 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, .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_check_power_down(struct sprd_rtc *rtc) { u32 val; int ret; ret = regmap_read(rtc->regmap, rtc->base + SPRD_RTC_PWR_STS, &val); if (ret) return ret; /* * If the RTC power status value is SPRD_RTC_POWER_RESET_VALUE, which * means the RTC has been powered down, so the RTC time values are * invalid. */ rtc->valid = val != SPRD_RTC_POWER_RESET_VALUE; return 0; } static int sprd_rtc_check_alarm_int(struct sprd_rtc *rtc) { u32 val; int ret; ret = regmap_read(rtc->regmap, rtc->base + SPRD_RTC_SPG_VALUE, &val); if (ret) return ret; /* * The SPRD_RTC_INT_EN register is not put in always-power-on region * supplied by VDDRTC, so we should check if we need enable the alarm * interrupt when system booting. * * If we have set SPRD_RTC_POWEROFF_ALM_FLAG which is saved in * always-power-on region, that means we have set one alarm last time, * so we should enable the alarm interrupt to help RTC core to see if * there is an alarm already set in RTC hardware. */ if (!(val & SPRD_RTC_POWEROFF_ALM_FLAG)) return 0; return regmap_update_bits(rtc->regmap, rtc->base + SPRD_RTC_INT_EN, SPRD_RTC_ALARM_EN, SPRD_RTC_ALARM_EN); } 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) return rtc->irq; rtc->rtc = devm_rtc_allocate_device(&pdev->dev); if (IS_ERR(rtc->rtc)) return PTR_ERR(rtc->rtc); rtc->dev = &pdev->dev; platform_set_drvdata(pdev, rtc); /* check if we need set the alarm interrupt */ ret = sprd_rtc_check_alarm_int(rtc); if (ret) { dev_err(&pdev->dev, "failed to check RTC alarm interrupt\n"); return ret; } /* check if RTC time values are valid */ ret = sprd_rtc_check_power_down(rtc); if (ret) { dev_err(&pdev->dev, "failed to check RTC time values\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; } device_init_wakeup(&pdev->dev, 1); rtc->rtc->ops = &sprd_rtc_ops; rtc->rtc->range_min = 0; rtc->rtc->range_max = 5662310399LL; ret = devm_rtc_register_device(rtc->rtc); if (ret) { device_init_wakeup(&pdev->dev, 0); return ret; } return 0; } static const struct of_device_id sprd_rtc_of_match[] = { { .compatible = "sprd,sc2731-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, }; module_platform_driver(sprd_rtc_driver); MODULE_LICENSE("GPL v2"); MODULE_DESCRIPTION("Spreadtrum RTC Device Driver"); MODULE_AUTHOR("Baolin Wang ");