/* * Driver for the Epson RTC module RX-8010 SJ * * Copyright(C) Timesys Corporation 2015 * Copyright(C) General Electric Company 2015 * * 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/bcd.h> #include <linux/bitops.h> #include <linux/i2c.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/rtc.h> #define RX8010_SEC 0x10 #define RX8010_MIN 0x11 #define RX8010_HOUR 0x12 #define RX8010_WDAY 0x13 #define RX8010_MDAY 0x14 #define RX8010_MONTH 0x15 #define RX8010_YEAR 0x16 #define RX8010_YEAR 0x16 #define RX8010_RESV17 0x17 #define RX8010_ALMIN 0x18 #define RX8010_ALHOUR 0x19 #define RX8010_ALWDAY 0x1A #define RX8010_TCOUNT0 0x1B #define RX8010_TCOUNT1 0x1C #define RX8010_EXT 0x1D #define RX8010_FLAG 0x1E #define RX8010_CTRL 0x1F /* 0x20 to 0x2F are user registers */ #define RX8010_RESV30 0x30 #define RX8010_RESV31 0x32 #define RX8010_IRQ 0x32 #define RX8010_EXT_WADA BIT(3) #define RX8010_FLAG_VLF BIT(1) #define RX8010_FLAG_AF BIT(3) #define RX8010_FLAG_TF BIT(4) #define RX8010_FLAG_UF BIT(5) #define RX8010_CTRL_AIE BIT(3) #define RX8010_CTRL_UIE BIT(5) #define RX8010_CTRL_STOP BIT(6) #define RX8010_CTRL_TEST BIT(7) #define RX8010_ALARM_AE BIT(7) static const struct i2c_device_id rx8010_id[] = { { "rx8010", 0 }, { } }; MODULE_DEVICE_TABLE(i2c, rx8010_id); static const struct of_device_id rx8010_of_match[] = { { .compatible = "epson,rx8010" }, { } }; MODULE_DEVICE_TABLE(of, rx8010_of_match); struct rx8010_data { struct i2c_client *client; struct rtc_device *rtc; u8 ctrlreg; }; static irqreturn_t rx8010_irq_1_handler(int irq, void *dev_id) { struct i2c_client *client = dev_id; struct rx8010_data *rx8010 = i2c_get_clientdata(client); int flagreg; mutex_lock(&rx8010->rtc->ops_lock); flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG); if (flagreg <= 0) { mutex_unlock(&rx8010->rtc->ops_lock); return IRQ_NONE; } if (flagreg & RX8010_FLAG_VLF) dev_warn(&client->dev, "Frequency stop detected\n"); if (flagreg & RX8010_FLAG_TF) { flagreg &= ~RX8010_FLAG_TF; rtc_update_irq(rx8010->rtc, 1, RTC_PF | RTC_IRQF); } if (flagreg & RX8010_FLAG_AF) { flagreg &= ~RX8010_FLAG_AF; rtc_update_irq(rx8010->rtc, 1, RTC_AF | RTC_IRQF); } if (flagreg & RX8010_FLAG_UF) { flagreg &= ~RX8010_FLAG_UF; rtc_update_irq(rx8010->rtc, 1, RTC_UF | RTC_IRQF); } i2c_smbus_write_byte_data(client, RX8010_FLAG, flagreg); mutex_unlock(&rx8010->rtc->ops_lock); return IRQ_HANDLED; } static int rx8010_get_time(struct device *dev, struct rtc_time *dt) { struct rx8010_data *rx8010 = dev_get_drvdata(dev); u8 date[7]; int flagreg; int err; flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG); if (flagreg < 0) return flagreg; if (flagreg & RX8010_FLAG_VLF) { dev_warn(dev, "Frequency stop detected\n"); return -EINVAL; } err = i2c_smbus_read_i2c_block_data(rx8010->client, RX8010_SEC, 7, date); if (err != 7) return err < 0 ? err : -EIO; dt->tm_sec = bcd2bin(date[RX8010_SEC - RX8010_SEC] & 0x7f); dt->tm_min = bcd2bin(date[RX8010_MIN - RX8010_SEC] & 0x7f); dt->tm_hour = bcd2bin(date[RX8010_HOUR - RX8010_SEC] & 0x3f); dt->tm_mday = bcd2bin(date[RX8010_MDAY - RX8010_SEC] & 0x3f); dt->tm_mon = bcd2bin(date[RX8010_MONTH - RX8010_SEC] & 0x1f) - 1; dt->tm_year = bcd2bin(date[RX8010_YEAR - RX8010_SEC]) + 100; dt->tm_wday = ffs(date[RX8010_WDAY - RX8010_SEC] & 0x7f); return rtc_valid_tm(dt); } static int rx8010_set_time(struct device *dev, struct rtc_time *dt) { struct rx8010_data *rx8010 = dev_get_drvdata(dev); u8 date[7]; int ctrl, flagreg; int ret; if ((dt->tm_year < 100) || (dt->tm_year > 199)) return -EINVAL; /* set STOP bit before changing clock/calendar */ ctrl = i2c_smbus_read_byte_data(rx8010->client, RX8010_CTRL); if (ctrl < 0) return ctrl; rx8010->ctrlreg = ctrl | RX8010_CTRL_STOP; ret = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL, rx8010->ctrlreg); if (ret < 0) return ret; date[RX8010_SEC - RX8010_SEC] = bin2bcd(dt->tm_sec); date[RX8010_MIN - RX8010_SEC] = bin2bcd(dt->tm_min); date[RX8010_HOUR - RX8010_SEC] = bin2bcd(dt->tm_hour); date[RX8010_MDAY - RX8010_SEC] = bin2bcd(dt->tm_mday); date[RX8010_MONTH - RX8010_SEC] = bin2bcd(dt->tm_mon + 1); date[RX8010_YEAR - RX8010_SEC] = bin2bcd(dt->tm_year - 100); date[RX8010_WDAY - RX8010_SEC] = bin2bcd(1 << dt->tm_wday); ret = i2c_smbus_write_i2c_block_data(rx8010->client, RX8010_SEC, 7, date); if (ret < 0) return ret; /* clear STOP bit after changing clock/calendar */ ctrl = i2c_smbus_read_byte_data(rx8010->client, RX8010_CTRL); if (ctrl < 0) return ctrl; rx8010->ctrlreg = ctrl & ~RX8010_CTRL_STOP; ret = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL, rx8010->ctrlreg); if (ret < 0) return ret; flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG); if (flagreg < 0) { return flagreg; } if (flagreg & RX8010_FLAG_VLF) ret = i2c_smbus_write_byte_data(rx8010->client, RX8010_FLAG, flagreg & ~RX8010_FLAG_VLF); return 0; } static int rx8010_init_client(struct i2c_client *client) { struct rx8010_data *rx8010 = i2c_get_clientdata(client); u8 ctrl[2]; int need_clear = 0, err = 0; /* Initialize reserved registers as specified in datasheet */ err = i2c_smbus_write_byte_data(client, RX8010_RESV17, 0xD8); if (err < 0) return err; err = i2c_smbus_write_byte_data(client, RX8010_RESV30, 0x00); if (err < 0) return err; err = i2c_smbus_write_byte_data(client, RX8010_RESV31, 0x08); if (err < 0) return err; err = i2c_smbus_write_byte_data(client, RX8010_IRQ, 0x00); if (err < 0) return err; err = i2c_smbus_read_i2c_block_data(rx8010->client, RX8010_FLAG, 2, ctrl); if (err != 2) return err < 0 ? err : -EIO; if (ctrl[0] & RX8010_FLAG_VLF) dev_warn(&client->dev, "Frequency stop was detected\n"); if (ctrl[0] & RX8010_FLAG_AF) { dev_warn(&client->dev, "Alarm was detected\n"); need_clear = 1; } if (ctrl[0] & RX8010_FLAG_TF) need_clear = 1; if (ctrl[0] & RX8010_FLAG_UF) need_clear = 1; if (need_clear) { ctrl[0] &= ~(RX8010_FLAG_AF | RX8010_FLAG_TF | RX8010_FLAG_UF); err = i2c_smbus_write_byte_data(client, RX8010_FLAG, ctrl[0]); if (err < 0) return err; } rx8010->ctrlreg = (ctrl[1] & ~RX8010_CTRL_TEST); return err; } static int rx8010_read_alarm(struct device *dev, struct rtc_wkalrm *t) { struct rx8010_data *rx8010 = dev_get_drvdata(dev); struct i2c_client *client = rx8010->client; u8 alarmvals[3]; int flagreg; int err; err = i2c_smbus_read_i2c_block_data(client, RX8010_ALMIN, 3, alarmvals); if (err != 3) return err < 0 ? err : -EIO; flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG); if (flagreg < 0) return flagreg; t->time.tm_sec = 0; t->time.tm_min = bcd2bin(alarmvals[0] & 0x7f); t->time.tm_hour = bcd2bin(alarmvals[1] & 0x3f); if (!(alarmvals[2] & RX8010_ALARM_AE)) t->time.tm_mday = bcd2bin(alarmvals[2] & 0x7f); t->enabled = !!(rx8010->ctrlreg & RX8010_CTRL_AIE); t->pending = (flagreg & RX8010_FLAG_AF) && t->enabled; return err; } static int rx8010_set_alarm(struct device *dev, struct rtc_wkalrm *t) { struct i2c_client *client = to_i2c_client(dev); struct rx8010_data *rx8010 = dev_get_drvdata(dev); u8 alarmvals[3]; int extreg, flagreg; int err; flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG); if (flagreg < 0) { return flagreg; } if (rx8010->ctrlreg & (RX8010_CTRL_AIE | RX8010_CTRL_UIE)) { rx8010->ctrlreg &= ~(RX8010_CTRL_AIE | RX8010_CTRL_UIE); err = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL, rx8010->ctrlreg); if (err < 0) { return err; } } flagreg &= ~RX8010_FLAG_AF; err = i2c_smbus_write_byte_data(rx8010->client, RX8010_FLAG, flagreg); if (err < 0) return err; alarmvals[0] = bin2bcd(t->time.tm_min); alarmvals[1] = bin2bcd(t->time.tm_hour); alarmvals[2] = bin2bcd(t->time.tm_mday); err = i2c_smbus_write_i2c_block_data(rx8010->client, RX8010_ALMIN, 2, alarmvals); if (err < 0) return err; extreg = i2c_smbus_read_byte_data(client, RX8010_EXT); if (extreg < 0) return extreg; extreg |= RX8010_EXT_WADA; err = i2c_smbus_write_byte_data(rx8010->client, RX8010_EXT, extreg); if (err < 0) return err; if (alarmvals[2] == 0) alarmvals[2] |= RX8010_ALARM_AE; err = i2c_smbus_write_byte_data(rx8010->client, RX8010_ALWDAY, alarmvals[2]); if (err < 0) return err; if (t->enabled) { if (rx8010->rtc->uie_rtctimer.enabled) rx8010->ctrlreg |= RX8010_CTRL_UIE; if (rx8010->rtc->aie_timer.enabled) rx8010->ctrlreg |= (RX8010_CTRL_AIE | RX8010_CTRL_UIE); err = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL, rx8010->ctrlreg); if (err < 0) return err; } return 0; } static int rx8010_alarm_irq_enable(struct device *dev, unsigned int enabled) { struct i2c_client *client = to_i2c_client(dev); struct rx8010_data *rx8010 = dev_get_drvdata(dev); int flagreg; u8 ctrl; int err; ctrl = rx8010->ctrlreg; if (enabled) { if (rx8010->rtc->uie_rtctimer.enabled) ctrl |= RX8010_CTRL_UIE; if (rx8010->rtc->aie_timer.enabled) ctrl |= (RX8010_CTRL_AIE | RX8010_CTRL_UIE); } else { if (!rx8010->rtc->uie_rtctimer.enabled) ctrl &= ~RX8010_CTRL_UIE; if (!rx8010->rtc->aie_timer.enabled) ctrl &= ~RX8010_CTRL_AIE; } flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG); if (flagreg < 0) return flagreg; flagreg &= ~RX8010_FLAG_AF; err = i2c_smbus_write_byte_data(rx8010->client, RX8010_FLAG, flagreg); if (err < 0) return err; if (ctrl != rx8010->ctrlreg) { rx8010->ctrlreg = ctrl; err = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL, rx8010->ctrlreg); if (err < 0) return err; } return 0; } static int rx8010_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) { struct i2c_client *client = to_i2c_client(dev); struct rx8010_data *rx8010 = dev_get_drvdata(dev); int ret, tmp; int flagreg; switch (cmd) { case RTC_VL_READ: flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG); if (flagreg < 0) return flagreg; tmp = !!(flagreg & RX8010_FLAG_VLF); if (copy_to_user((void __user *)arg, &tmp, sizeof(int))) return -EFAULT; return 0; case RTC_VL_CLR: flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG); if (flagreg < 0) { return flagreg; } flagreg &= ~RX8010_FLAG_VLF; ret = i2c_smbus_write_byte_data(client, RX8010_FLAG, flagreg); if (ret < 0) return ret; return 0; default: return -ENOIOCTLCMD; } } static struct rtc_class_ops rx8010_rtc_ops = { .read_time = rx8010_get_time, .set_time = rx8010_set_time, .ioctl = rx8010_ioctl, }; static int rx8010_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent); struct rx8010_data *rx8010; int err = 0; if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_I2C_BLOCK)) { dev_err(&adapter->dev, "doesn't support required functionality\n"); return -EIO; } rx8010 = devm_kzalloc(&client->dev, sizeof(struct rx8010_data), GFP_KERNEL); if (!rx8010) return -ENOMEM; rx8010->client = client; i2c_set_clientdata(client, rx8010); err = rx8010_init_client(client); if (err) return err; if (client->irq > 0) { dev_info(&client->dev, "IRQ %d supplied\n", client->irq); err = devm_request_threaded_irq(&client->dev, client->irq, NULL, rx8010_irq_1_handler, IRQF_TRIGGER_LOW | IRQF_ONESHOT, "rx8010", client); if (err) { dev_err(&client->dev, "unable to request IRQ\n"); client->irq = 0; } else { rx8010_rtc_ops.read_alarm = rx8010_read_alarm; rx8010_rtc_ops.set_alarm = rx8010_set_alarm; rx8010_rtc_ops.alarm_irq_enable = rx8010_alarm_irq_enable; } } rx8010->rtc = devm_rtc_device_register(&client->dev, client->name, &rx8010_rtc_ops, THIS_MODULE); if (IS_ERR(rx8010->rtc)) { dev_err(&client->dev, "unable to register the class device\n"); return PTR_ERR(rx8010->rtc); } rx8010->rtc->max_user_freq = 1; return err; } static struct i2c_driver rx8010_driver = { .driver = { .name = "rtc-rx8010", .of_match_table = of_match_ptr(rx8010_of_match), }, .probe = rx8010_probe, .id_table = rx8010_id, }; module_i2c_driver(rx8010_driver); MODULE_AUTHOR("Akshay Bhat <akshay.bhat@timesys.com>"); MODULE_DESCRIPTION("Epson RX8010SJ RTC driver"); MODULE_LICENSE("GPL v2");