diff options
Diffstat (limited to 'drivers/rtc/rtc-rx8010.c')
| -rw-r--r-- | drivers/rtc/rtc-rx8010.c | 523 |
1 files changed, 523 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-rx8010.c b/drivers/rtc/rtc-rx8010.c new file mode 100644 index 000000000000..772d221ec2d9 --- /dev/null +++ b/drivers/rtc/rtc-rx8010.c @@ -0,0 +1,523 @@ +/* + * 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); + +struct rx8010_data { + struct i2c_client *client; + struct rtc_device *rtc; + u8 ctrlreg; + spinlock_t flags_lock; +}; + +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; + + spin_lock(&rx8010->flags_lock); + + flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG); + + if (flagreg <= 0) { + spin_unlock(&rx8010->flags_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); + + spin_unlock(&rx8010->flags_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; + unsigned long irqflags; + + 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; + + spin_lock_irqsave(&rx8010->flags_lock, irqflags); + + flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG); + if (flagreg < 0) { + spin_unlock_irqrestore(&rx8010->flags_lock, irqflags); + return flagreg; + } + + if (flagreg & RX8010_FLAG_VLF) + ret = i2c_smbus_write_byte_data(rx8010->client, RX8010_FLAG, + flagreg & ~RX8010_FLAG_VLF); + + spin_unlock_irqrestore(&rx8010->flags_lock, irqflags); + + 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 = -1; + else + t->time.tm_mday = bcd2bin(alarmvals[2] & 0x7f); + + t->time.tm_wday = -1; + t->time.tm_mon = -1; + t->time.tm_year = -1; + + 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; + unsigned long irqflags; + + spin_lock_irqsave(&rx8010->flags_lock, irqflags); + flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG); + if (flagreg < 0) { + spin_unlock_irqrestore(&rx8010->flags_lock, irqflags); + 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) { + spin_unlock_irqrestore(&rx8010->flags_lock, irqflags); + return err; + } + } + + flagreg &= ~RX8010_FLAG_AF; + err = i2c_smbus_write_byte_data(rx8010->client, RX8010_FLAG, flagreg); + spin_unlock_irqrestore(&rx8010->flags_lock, irqflags); + 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; + unsigned long irqflags; + + 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: + spin_lock_irqsave(&rx8010->flags_lock, irqflags); + flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG); + if (flagreg < 0) { + spin_unlock_irqrestore(&rx8010->flags_lock, irqflags); + return flagreg; + } + + flagreg &= ~RX8010_FLAG_VLF; + ret = i2c_smbus_write_byte_data(client, RX8010_FLAG, flagreg); + spin_unlock_irqrestore(&rx8010->flags_lock, irqflags); + 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); + + spin_lock_init(&rx8010->flags_lock); + + 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", + }, + .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"); |