/* Copyright (c) 2012-2015, The Linux Foundation. All rights reserved. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 and * only version 2 as published by the Free Software Foundation. * * 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. */ #include #include #include #include #include #include #include #include #include #include #include /* RTC/ALARM Register offsets */ #define REG_OFFSET_ALARM_RW 0x40 #define REG_OFFSET_ALARM_CTRL1 0x46 #define REG_OFFSET_ALARM_CTRL2 0x48 #define REG_OFFSET_RTC_WRITE 0x40 #define REG_OFFSET_RTC_CTRL 0x46 #define REG_OFFSET_RTC_READ 0x48 #define REG_OFFSET_PERP_SUBTYPE 0x05 /* RTC_CTRL register bit fields */ #define BIT_RTC_ENABLE BIT(7) #define BIT_RTC_ALARM_ENABLE BIT(7) #define BIT_RTC_ABORT_ENABLE BIT(0) #define BIT_RTC_ALARM_CLEAR BIT(0) /* RTC/ALARM peripheral subtype values */ #define RTC_PERPH_SUBTYPE 0x1 #define ALARM_PERPH_SUBTYPE 0x3 #define NUM_8_BIT_RTC_REGS 0x4 #define TO_SECS(arr) (arr[0] | (arr[1] << 8) | (arr[2] << 16) | \ (arr[3] << 24)) /* Module parameter to control power-on-alarm */ bool poweron_alarm; module_param(poweron_alarm, bool, 0644); MODULE_PARM_DESC(poweron_alarm, "Enable/Disable power-on alarm"); EXPORT_SYMBOL(poweron_alarm); /* rtc driver internal structure */ struct qpnp_rtc { u8 rtc_ctrl_reg; u8 alarm_ctrl_reg1; u16 rtc_base; u16 alarm_base; u32 rtc_write_enable; u32 rtc_alarm_powerup; int rtc_alarm_irq; struct device *rtc_dev; struct rtc_device *rtc; struct spmi_device *spmi; spinlock_t alarm_ctrl_lock; }; static int qpnp_read_wrapper(struct qpnp_rtc *rtc_dd, u8 *rtc_val, u16 base, int count) { int rc; struct spmi_device *spmi = rtc_dd->spmi; rc = spmi_ext_register_readl(spmi->ctrl, spmi->sid, base, rtc_val, count); if (rc) { dev_err(rtc_dd->rtc_dev, "SPMI read failed\n"); return rc; } return 0; } static int qpnp_write_wrapper(struct qpnp_rtc *rtc_dd, u8 *rtc_val, u16 base, int count) { int rc; struct spmi_device *spmi = rtc_dd->spmi; rc = spmi_ext_register_writel(spmi->ctrl, spmi->sid, base, rtc_val, count); if (rc) { dev_err(rtc_dd->rtc_dev, "SPMI write failed\n"); return rc; } return 0; } static int qpnp_rtc_set_time(struct device *dev, struct rtc_time *tm) { int rc; unsigned long secs, irq_flags; u8 value[4], reg = 0, alarm_enabled = 0, ctrl_reg; u8 rtc_disabled = 0, rtc_ctrl_reg; struct qpnp_rtc *rtc_dd = dev_get_drvdata(dev); rtc_tm_to_time(tm, &secs); value[0] = secs & 0xFF; value[1] = (secs >> 8) & 0xFF; value[2] = (secs >> 16) & 0xFF; value[3] = (secs >> 24) & 0xFF; dev_dbg(dev, "Seconds value to be written to RTC = %lu\n", secs); spin_lock_irqsave(&rtc_dd->alarm_ctrl_lock, irq_flags); ctrl_reg = rtc_dd->alarm_ctrl_reg1; if (ctrl_reg & BIT_RTC_ALARM_ENABLE) { alarm_enabled = 1; ctrl_reg &= ~BIT_RTC_ALARM_ENABLE; rc = qpnp_write_wrapper(rtc_dd, &ctrl_reg, rtc_dd->alarm_base + REG_OFFSET_ALARM_CTRL1, 1); if (rc) { dev_err(dev, "Write to ALARM ctrl reg failed\n"); goto rtc_rw_fail; } } else spin_unlock_irqrestore(&rtc_dd->alarm_ctrl_lock, irq_flags); /* * 32 bit seconds value is coverted to four 8 bit values * |<------ 32 bit time value in seconds ------>| * <- 8 bit ->|<- 8 bit ->|<- 8 bit ->|<- 8 bit ->| * ---------------------------------------------- * | BYTE[3] | BYTE[2] | BYTE[1] | BYTE[0] | * ---------------------------------------------- * * RTC has four 8 bit registers for writting time in seconds: * WDATA[3], WDATA[2], WDATA[1], WDATA[0] * * Write to the RTC registers should be done in following order * Clear WDATA[0] register * * Write BYTE[1], BYTE[2] and BYTE[3] of time to * RTC WDATA[3], WDATA[2], WDATA[1] registers * * Write BYTE[0] of time to RTC WDATA[0] register * * Clearing BYTE[0] and writting in the end will prevent any * unintentional overflow from WDATA[0] to higher bytes during the * write operation */ /* Disable RTC H/w before writing on RTC register*/ rtc_ctrl_reg = rtc_dd->rtc_ctrl_reg; if (rtc_ctrl_reg & BIT_RTC_ENABLE) { rtc_disabled = 1; rtc_ctrl_reg &= ~BIT_RTC_ENABLE; rc = qpnp_write_wrapper(rtc_dd, &rtc_ctrl_reg, rtc_dd->rtc_base + REG_OFFSET_RTC_CTRL, 1); if (rc) { dev_err(dev, "Disabling of RTC control reg failed" " with error:%d\n", rc); goto rtc_rw_fail; } rtc_dd->rtc_ctrl_reg = rtc_ctrl_reg; } /* Clear WDATA[0] */ reg = 0x0; rc = qpnp_write_wrapper(rtc_dd, ®, rtc_dd->rtc_base + REG_OFFSET_RTC_WRITE, 1); if (rc) { dev_err(dev, "Write to RTC reg failed\n"); goto rtc_rw_fail; } /* Write to WDATA[3], WDATA[2] and WDATA[1] */ rc = qpnp_write_wrapper(rtc_dd, &value[1], rtc_dd->rtc_base + REG_OFFSET_RTC_WRITE + 1, 3); if (rc) { dev_err(dev, "Write to RTC reg failed\n"); goto rtc_rw_fail; } /* Write to WDATA[0] */ rc = qpnp_write_wrapper(rtc_dd, value, rtc_dd->rtc_base + REG_OFFSET_RTC_WRITE, 1); if (rc) { dev_err(dev, "Write to RTC reg failed\n"); goto rtc_rw_fail; } /* Enable RTC H/w after writing on RTC register*/ if (rtc_disabled) { rtc_ctrl_reg |= BIT_RTC_ENABLE; rc = qpnp_write_wrapper(rtc_dd, &rtc_ctrl_reg, rtc_dd->rtc_base + REG_OFFSET_RTC_CTRL, 1); if (rc) { dev_err(dev, "Enabling of RTC control reg failed" " with error:%d\n", rc); goto rtc_rw_fail; } rtc_dd->rtc_ctrl_reg = rtc_ctrl_reg; } if (alarm_enabled) { ctrl_reg |= BIT_RTC_ALARM_ENABLE; rc = qpnp_write_wrapper(rtc_dd, &ctrl_reg, rtc_dd->alarm_base + REG_OFFSET_ALARM_CTRL1, 1); if (rc) { dev_err(dev, "Write to ALARM ctrl reg failed\n"); goto rtc_rw_fail; } } rtc_dd->alarm_ctrl_reg1 = ctrl_reg; rtc_rw_fail: if (alarm_enabled) spin_unlock_irqrestore(&rtc_dd->alarm_ctrl_lock, irq_flags); return rc; } static int qpnp_rtc_read_time(struct device *dev, struct rtc_time *tm) { int rc; u8 value[4], reg; unsigned long secs; struct qpnp_rtc *rtc_dd = dev_get_drvdata(dev); rc = qpnp_read_wrapper(rtc_dd, value, rtc_dd->rtc_base + REG_OFFSET_RTC_READ, NUM_8_BIT_RTC_REGS); if (rc) { dev_err(dev, "Read from RTC reg failed\n"); return rc; } /* * Read the LSB again and check if there has been a carry over * If there is, redo the read operation */ rc = qpnp_read_wrapper(rtc_dd, ®, rtc_dd->rtc_base + REG_OFFSET_RTC_READ, 1); if (rc) { dev_err(dev, "Read from RTC reg failed\n"); return rc; } if (reg < value[0]) { rc = qpnp_read_wrapper(rtc_dd, value, rtc_dd->rtc_base + REG_OFFSET_RTC_READ, NUM_8_BIT_RTC_REGS); if (rc) { dev_err(dev, "Read from RTC reg failed\n"); return rc; } } secs = TO_SECS(value); rtc_time_to_tm(secs, tm); rc = rtc_valid_tm(tm); if (rc) { dev_err(dev, "Invalid time read from RTC\n"); return rc; } dev_dbg(dev, "secs = %lu, h:m:s == %d:%d:%d, d/m/y = %d/%d/%d\n", secs, tm->tm_hour, tm->tm_min, tm->tm_sec, tm->tm_mday, tm->tm_mon, tm->tm_year); return 0; } static int qpnp_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) { int rc; u8 value[4], ctrl_reg; unsigned long secs, secs_rtc, irq_flags; struct qpnp_rtc *rtc_dd = dev_get_drvdata(dev); struct rtc_time rtc_tm; rtc_tm_to_time(&alarm->time, &secs); /* * Read the current RTC time and verify if the alarm time is in the * past. If yes, return invalid */ rc = qpnp_rtc_read_time(dev, &rtc_tm); if (rc) { dev_err(dev, "Unable to read RTC time\n"); return -EINVAL; } rtc_tm_to_time(&rtc_tm, &secs_rtc); if (secs < secs_rtc) { dev_err(dev, "Trying to set alarm in the past\n"); return -EINVAL; } value[0] = secs & 0xFF; value[1] = (secs >> 8) & 0xFF; value[2] = (secs >> 16) & 0xFF; value[3] = (secs >> 24) & 0xFF; spin_lock_irqsave(&rtc_dd->alarm_ctrl_lock, irq_flags); rc = qpnp_write_wrapper(rtc_dd, value, rtc_dd->alarm_base + REG_OFFSET_ALARM_RW, NUM_8_BIT_RTC_REGS); if (rc) { dev_err(dev, "Write to ALARM reg failed\n"); goto rtc_rw_fail; } ctrl_reg = (alarm->enabled) ? (rtc_dd->alarm_ctrl_reg1 | BIT_RTC_ALARM_ENABLE) : (rtc_dd->alarm_ctrl_reg1 & ~BIT_RTC_ALARM_ENABLE); rc = qpnp_write_wrapper(rtc_dd, &ctrl_reg, rtc_dd->alarm_base + REG_OFFSET_ALARM_CTRL1, 1); if (rc) { dev_err(dev, "Write to ALARM cntrol reg failed\n"); goto rtc_rw_fail; } rtc_dd->alarm_ctrl_reg1 = ctrl_reg; dev_dbg(dev, "Alarm Set for h:r:s=%d:%d:%d, d/m/y=%d/%d/%d\n", alarm->time.tm_hour, alarm->time.tm_min, alarm->time.tm_sec, alarm->time.tm_mday, alarm->time.tm_mon, alarm->time.tm_year); rtc_rw_fail: spin_unlock_irqrestore(&rtc_dd->alarm_ctrl_lock, irq_flags); return rc; } static int qpnp_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) { int rc; u8 value[4]; unsigned long secs; struct qpnp_rtc *rtc_dd = dev_get_drvdata(dev); rc = qpnp_read_wrapper(rtc_dd, value, rtc_dd->alarm_base + REG_OFFSET_ALARM_RW, NUM_8_BIT_RTC_REGS); if (rc) { dev_err(dev, "Read from ALARM reg failed\n"); return rc; } secs = TO_SECS(value); rtc_time_to_tm(secs, &alarm->time); rc = rtc_valid_tm(&alarm->time); if (rc) { dev_err(dev, "Invalid time read from RTC\n"); return rc; } dev_dbg(dev, "Alarm set for - h:r:s=%d:%d:%d, d/m/y=%d/%d/%d\n", alarm->time.tm_hour, alarm->time.tm_min, alarm->time.tm_sec, alarm->time.tm_mday, alarm->time.tm_mon, alarm->time.tm_year); return 0; } static int qpnp_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) { int rc; unsigned long irq_flags; struct qpnp_rtc *rtc_dd = dev_get_drvdata(dev); u8 ctrl_reg; u8 value[4] = {0}; spin_lock_irqsave(&rtc_dd->alarm_ctrl_lock, irq_flags); ctrl_reg = rtc_dd->alarm_ctrl_reg1; ctrl_reg = enabled ? (ctrl_reg | BIT_RTC_ALARM_ENABLE) : (ctrl_reg & ~BIT_RTC_ALARM_ENABLE); rc = qpnp_write_wrapper(rtc_dd, &ctrl_reg, rtc_dd->alarm_base + REG_OFFSET_ALARM_CTRL1, 1); if (rc) { dev_err(dev, "Write to ALARM control reg failed\n"); goto rtc_rw_fail; } rtc_dd->alarm_ctrl_reg1 = ctrl_reg; /* Clear Alarm register */ if (!enabled) { rc = qpnp_write_wrapper(rtc_dd, value, rtc_dd->alarm_base + REG_OFFSET_ALARM_RW, NUM_8_BIT_RTC_REGS); if (rc) dev_err(dev, "Clear ALARM value reg failed\n"); } rtc_rw_fail: spin_unlock_irqrestore(&rtc_dd->alarm_ctrl_lock, irq_flags); return rc; } static struct rtc_class_ops qpnp_rtc_ops = { .read_time = qpnp_rtc_read_time, .set_alarm = qpnp_rtc_set_alarm, .read_alarm = qpnp_rtc_read_alarm, .alarm_irq_enable = qpnp_rtc_alarm_irq_enable, }; static irqreturn_t qpnp_alarm_trigger(int irq, void *dev_id) { struct qpnp_rtc *rtc_dd = dev_id; u8 ctrl_reg; int rc; unsigned long irq_flags; rtc_update_irq(rtc_dd->rtc, 1, RTC_IRQF | RTC_AF); spin_lock_irqsave(&rtc_dd->alarm_ctrl_lock, irq_flags); /* Clear the alarm enable bit */ ctrl_reg = rtc_dd->alarm_ctrl_reg1; ctrl_reg &= ~BIT_RTC_ALARM_ENABLE; rc = qpnp_write_wrapper(rtc_dd, &ctrl_reg, rtc_dd->alarm_base + REG_OFFSET_ALARM_CTRL1, 1); if (rc) { spin_unlock_irqrestore(&rtc_dd->alarm_ctrl_lock, irq_flags); dev_err(rtc_dd->rtc_dev, "Write to ALARM control reg failed\n"); goto rtc_alarm_handled; } rtc_dd->alarm_ctrl_reg1 = ctrl_reg; spin_unlock_irqrestore(&rtc_dd->alarm_ctrl_lock, irq_flags); /* Set ALARM_CLR bit */ ctrl_reg = 0x1; rc = qpnp_write_wrapper(rtc_dd, &ctrl_reg, rtc_dd->alarm_base + REG_OFFSET_ALARM_CTRL2, 1); if (rc) dev_err(rtc_dd->rtc_dev, "Write to ALARM control reg failed\n"); rtc_alarm_handled: return IRQ_HANDLED; } static int qpnp_rtc_probe(struct spmi_device *spmi) { int rc; u8 subtype; struct qpnp_rtc *rtc_dd; struct resource *resource; struct spmi_resource *spmi_resource; rtc_dd = devm_kzalloc(&spmi->dev, sizeof(*rtc_dd), GFP_KERNEL); if (rtc_dd == NULL) { dev_err(&spmi->dev, "Unable to allocate memory!\n"); return -ENOMEM; } /* Get the rtc write property */ rc = of_property_read_u32(spmi->dev.of_node, "qcom,qpnp-rtc-write", &rtc_dd->rtc_write_enable); if (rc && rc != -EINVAL) { dev_err(&spmi->dev, "Error reading rtc_write_enable property %d\n", rc); return rc; } rc = of_property_read_u32(spmi->dev.of_node, "qcom,qpnp-rtc-alarm-pwrup", &rtc_dd->rtc_alarm_powerup); if (rc && rc != -EINVAL) { dev_err(&spmi->dev, "Error reading rtc_alarm_powerup property %d\n", rc); return rc; } /* Initialise spinlock to protect RTC control register */ spin_lock_init(&rtc_dd->alarm_ctrl_lock); rtc_dd->rtc_dev = &(spmi->dev); rtc_dd->spmi = spmi; /* Get RTC/ALARM resources */ spmi_for_each_container_dev(spmi_resource, spmi) { if (!spmi_resource) { dev_err(&spmi->dev, "%s: rtc_alarm: spmi resource absent!\n", __func__); rc = -ENXIO; goto fail_rtc_enable; } resource = spmi_get_resource(spmi, spmi_resource, IORESOURCE_MEM, 0); if (!(resource && resource->start)) { dev_err(&spmi->dev, "%s: node %s IO resource absent!\n", __func__, spmi->dev.of_node->full_name); rc = -ENXIO; goto fail_rtc_enable; } rc = qpnp_read_wrapper(rtc_dd, &subtype, resource->start + REG_OFFSET_PERP_SUBTYPE, 1); if (rc) { dev_err(&spmi->dev, "Peripheral subtype read failed\n"); goto fail_rtc_enable; } switch (subtype) { case RTC_PERPH_SUBTYPE: rtc_dd->rtc_base = resource->start; break; case ALARM_PERPH_SUBTYPE: rtc_dd->alarm_base = resource->start; rtc_dd->rtc_alarm_irq = spmi_get_irq(spmi, spmi_resource, 0); if (rtc_dd->rtc_alarm_irq < 0) { dev_err(&spmi->dev, "ALARM IRQ absent\n"); rc = -ENXIO; goto fail_rtc_enable; } break; default: dev_err(&spmi->dev, "Invalid peripheral subtype\n"); rc = -EINVAL; goto fail_rtc_enable; } } rc = qpnp_read_wrapper(rtc_dd, &rtc_dd->rtc_ctrl_reg, rtc_dd->rtc_base + REG_OFFSET_RTC_CTRL, 1); if (rc) { dev_err(&spmi->dev, "Read from RTC control reg failed\n"); goto fail_rtc_enable; } if (!(rtc_dd->rtc_ctrl_reg & BIT_RTC_ENABLE)) { dev_err(&spmi->dev, "RTC h/w disabled, rtc not registered\n"); goto fail_rtc_enable; } rc = qpnp_read_wrapper(rtc_dd, &rtc_dd->alarm_ctrl_reg1, rtc_dd->alarm_base + REG_OFFSET_ALARM_CTRL1, 1); if (rc) { dev_err(&spmi->dev, "Read from Alarm control reg failed\n"); goto fail_rtc_enable; } /* Enable abort enable feature */ rtc_dd->alarm_ctrl_reg1 |= BIT_RTC_ABORT_ENABLE; rc = qpnp_write_wrapper(rtc_dd, &rtc_dd->alarm_ctrl_reg1, rtc_dd->alarm_base + REG_OFFSET_ALARM_CTRL1, 1); if (rc) { dev_err(&spmi->dev, "SPMI write failed!\n"); goto fail_rtc_enable; } if (rtc_dd->rtc_write_enable == true) qpnp_rtc_ops.set_time = qpnp_rtc_set_time; dev_set_drvdata(&spmi->dev, rtc_dd); /* Register the RTC device */ rtc_dd->rtc = rtc_device_register("qpnp_rtc", &spmi->dev, &qpnp_rtc_ops, THIS_MODULE); if (IS_ERR(rtc_dd->rtc)) { dev_err(&spmi->dev, "%s: RTC registration failed (%ld)\n", __func__, PTR_ERR(rtc_dd->rtc)); rc = PTR_ERR(rtc_dd->rtc); goto fail_rtc_enable; } /* Init power_on_alarm after adding rtc device */ power_on_alarm_init(); /* Request the alarm IRQ */ rc = request_any_context_irq(rtc_dd->rtc_alarm_irq, qpnp_alarm_trigger, IRQF_TRIGGER_RISING, "qpnp_rtc_alarm", rtc_dd); if (rc) { dev_err(&spmi->dev, "Request IRQ failed (%d)\n", rc); goto fail_req_irq; } device_init_wakeup(&spmi->dev, 1); enable_irq_wake(rtc_dd->rtc_alarm_irq); dev_dbg(&spmi->dev, "Probe success !!\n"); return 0; fail_req_irq: rtc_device_unregister(rtc_dd->rtc); fail_rtc_enable: dev_set_drvdata(&spmi->dev, NULL); return rc; } static int qpnp_rtc_remove(struct spmi_device *spmi) { struct qpnp_rtc *rtc_dd = dev_get_drvdata(&spmi->dev); device_init_wakeup(&spmi->dev, 0); free_irq(rtc_dd->rtc_alarm_irq, rtc_dd); rtc_device_unregister(rtc_dd->rtc); dev_set_drvdata(&spmi->dev, NULL); return 0; } static void qpnp_rtc_shutdown(struct spmi_device *spmi) { u8 value[4] = {0}; u8 reg; int rc; unsigned long irq_flags; struct qpnp_rtc *rtc_dd; bool rtc_alarm_powerup; if (!spmi) { pr_err("qpnp-rtc: spmi device not found\n"); return; } rtc_dd = dev_get_drvdata(&spmi->dev); if (!rtc_dd) { pr_err("qpnp-rtc: rtc driver data not found\n"); return; } rtc_alarm_powerup = rtc_dd->rtc_alarm_powerup; if (!rtc_alarm_powerup && !poweron_alarm) { spin_lock_irqsave(&rtc_dd->alarm_ctrl_lock, irq_flags); dev_dbg(&spmi->dev, "Disabling alarm interrupts\n"); /* Disable RTC alarms */ reg = rtc_dd->alarm_ctrl_reg1; reg &= ~BIT_RTC_ALARM_ENABLE; rc = qpnp_write_wrapper(rtc_dd, ®, rtc_dd->alarm_base + REG_OFFSET_ALARM_CTRL1, 1); if (rc) { dev_err(rtc_dd->rtc_dev, "SPMI write failed\n"); goto fail_alarm_disable; } /* Clear Alarm register */ rc = qpnp_write_wrapper(rtc_dd, value, rtc_dd->alarm_base + REG_OFFSET_ALARM_RW, NUM_8_BIT_RTC_REGS); if (rc) dev_err(rtc_dd->rtc_dev, "SPMI write failed\n"); fail_alarm_disable: spin_unlock_irqrestore(&rtc_dd->alarm_ctrl_lock, irq_flags); } } static struct of_device_id spmi_match_table[] = { { .compatible = "qcom,qpnp-rtc", }, {} }; static struct spmi_driver qpnp_rtc_driver = { .probe = qpnp_rtc_probe, .remove = qpnp_rtc_remove, .shutdown = qpnp_rtc_shutdown, .driver = { .name = "qcom,qpnp-rtc", .owner = THIS_MODULE, .of_match_table = spmi_match_table, }, }; static int __init qpnp_rtc_init(void) { return spmi_driver_register(&qpnp_rtc_driver); } module_init(qpnp_rtc_init); static void __exit qpnp_rtc_exit(void) { spmi_driver_unregister(&qpnp_rtc_driver); } module_exit(qpnp_rtc_exit); MODULE_DESCRIPTION("SMPI PMIC RTC driver"); MODULE_LICENSE("GPL V2");