From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- drivers/rtc/rtc-pcf8523.c | 494 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 494 insertions(+) create mode 100644 drivers/rtc/rtc-pcf8523.c (limited to 'drivers/rtc/rtc-pcf8523.c') diff --git a/drivers/rtc/rtc-pcf8523.c b/drivers/rtc/rtc-pcf8523.c new file mode 100644 index 000000000..6174b3fd4 --- /dev/null +++ b/drivers/rtc/rtc-pcf8523.c @@ -0,0 +1,494 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2012 Avionic Design GmbH + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#define PCF8523_REG_CONTROL1 0x00 +#define PCF8523_CONTROL1_CAP_SEL BIT(7) +#define PCF8523_CONTROL1_STOP BIT(5) +#define PCF8523_CONTROL1_AIE BIT(1) + +#define PCF8523_REG_CONTROL2 0x01 +#define PCF8523_CONTROL2_AF BIT(3) + +#define PCF8523_REG_CONTROL3 0x02 +#define PCF8523_CONTROL3_PM GENMASK(7,5) +#define PCF8523_PM_STANDBY 0x7 +#define PCF8523_CONTROL3_BLF BIT(2) /* battery low bit, read-only */ +#define PCF8523_CONTROL3_BSF BIT(3) + +#define PCF8523_REG_SECONDS 0x03 +#define PCF8523_SECONDS_OS BIT(7) + +#define PCF8523_REG_MINUTES 0x04 +#define PCF8523_REG_HOURS 0x05 +#define PCF8523_REG_DAYS 0x06 +#define PCF8523_REG_WEEKDAYS 0x07 +#define PCF8523_REG_MONTHS 0x08 +#define PCF8523_REG_YEARS 0x09 + +#define PCF8523_REG_MINUTE_ALARM 0x0a +#define PCF8523_REG_HOUR_ALARM 0x0b +#define PCF8523_REG_DAY_ALARM 0x0c +#define PCF8523_REG_WEEKDAY_ALARM 0x0d +#define ALARM_DIS BIT(7) + +#define PCF8523_REG_OFFSET 0x0e +#define PCF8523_OFFSET_MODE BIT(7) + +#define PCF8523_TMR_CLKOUT_CTRL 0x0f + +struct pcf8523 { + struct rtc_device *rtc; + struct regmap *regmap; +}; + +static int pcf8523_load_capacitance(struct pcf8523 *pcf8523, struct device_node *node) +{ + u32 load, value = 0; + + load = 12500; + of_property_read_u32(node, "quartz-load-femtofarads", &load); + + switch (load) { + default: + dev_warn(&pcf8523->rtc->dev, "Unknown quartz-load-femtofarads value: %d. Assuming 12500", + load); + fallthrough; + case 12500: + value |= PCF8523_CONTROL1_CAP_SEL; + break; + case 7000: + break; + } + + return regmap_update_bits(pcf8523->regmap, PCF8523_REG_CONTROL1, + PCF8523_CONTROL1_CAP_SEL, value); +} + +static irqreturn_t pcf8523_irq(int irq, void *dev_id) +{ + struct pcf8523 *pcf8523 = dev_id; + u32 value; + int err; + + err = regmap_read(pcf8523->regmap, PCF8523_REG_CONTROL2, &value); + if (err < 0) + return IRQ_HANDLED; + + if (value & PCF8523_CONTROL2_AF) { + value &= ~PCF8523_CONTROL2_AF; + regmap_write(pcf8523->regmap, PCF8523_REG_CONTROL2, value); + rtc_update_irq(pcf8523->rtc, 1, RTC_IRQF | RTC_AF); + + return IRQ_HANDLED; + } + + return IRQ_NONE; +} + +static int pcf8523_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + struct pcf8523 *pcf8523 = dev_get_drvdata(dev); + u8 regs[7]; + int err; + + err = regmap_bulk_read(pcf8523->regmap, PCF8523_REG_SECONDS, regs, + sizeof(regs)); + if (err < 0) + return err; + + if (regs[0] & PCF8523_SECONDS_OS) + return -EINVAL; + + tm->tm_sec = bcd2bin(regs[0] & 0x7f); + tm->tm_min = bcd2bin(regs[1] & 0x7f); + tm->tm_hour = bcd2bin(regs[2] & 0x3f); + tm->tm_mday = bcd2bin(regs[3] & 0x3f); + tm->tm_wday = regs[4] & 0x7; + tm->tm_mon = bcd2bin(regs[5] & 0x1f) - 1; + tm->tm_year = bcd2bin(regs[6]) + 100; + + return 0; +} + +static int pcf8523_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct pcf8523 *pcf8523 = dev_get_drvdata(dev); + u8 regs[7]; + int err; + + err = regmap_update_bits(pcf8523->regmap, PCF8523_REG_CONTROL1, + PCF8523_CONTROL1_STOP, PCF8523_CONTROL1_STOP); + if (err < 0) + return err; + + /* This will purposely overwrite PCF8523_SECONDS_OS */ + regs[0] = bin2bcd(tm->tm_sec); + regs[1] = bin2bcd(tm->tm_min); + regs[2] = bin2bcd(tm->tm_hour); + regs[3] = bin2bcd(tm->tm_mday); + regs[4] = tm->tm_wday; + regs[5] = bin2bcd(tm->tm_mon + 1); + regs[6] = bin2bcd(tm->tm_year - 100); + + err = regmap_bulk_write(pcf8523->regmap, PCF8523_REG_SECONDS, regs, + sizeof(regs)); + if (err < 0) { + /* + * If the time cannot be set, restart the RTC anyway. Note + * that errors are ignored if the RTC cannot be started so + * that we have a chance to propagate the original error. + */ + regmap_update_bits(pcf8523->regmap, PCF8523_REG_CONTROL1, + PCF8523_CONTROL1_STOP, 0); + return err; + } + + return regmap_update_bits(pcf8523->regmap, PCF8523_REG_CONTROL1, + PCF8523_CONTROL1_STOP, 0); +} + +static int pcf8523_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *tm) +{ + struct pcf8523 *pcf8523 = dev_get_drvdata(dev); + u8 regs[4]; + u32 value; + int err; + + err = regmap_bulk_read(pcf8523->regmap, PCF8523_REG_MINUTE_ALARM, regs, + sizeof(regs)); + if (err < 0) + return err; + + tm->time.tm_sec = 0; + tm->time.tm_min = bcd2bin(regs[0] & 0x7F); + tm->time.tm_hour = bcd2bin(regs[1] & 0x3F); + tm->time.tm_mday = bcd2bin(regs[2] & 0x3F); + tm->time.tm_wday = bcd2bin(regs[3] & 0x7); + + err = regmap_read(pcf8523->regmap, PCF8523_REG_CONTROL1, &value); + if (err < 0) + return err; + tm->enabled = !!(value & PCF8523_CONTROL1_AIE); + + err = regmap_read(pcf8523->regmap, PCF8523_REG_CONTROL2, &value); + if (err < 0) + return err; + tm->pending = !!(value & PCF8523_CONTROL2_AF); + + return 0; +} + +static int pcf8523_irq_enable(struct device *dev, unsigned int enabled) +{ + struct pcf8523 *pcf8523 = dev_get_drvdata(dev); + + return regmap_update_bits(pcf8523->regmap, PCF8523_REG_CONTROL1, + PCF8523_CONTROL1_AIE, enabled ? + PCF8523_CONTROL1_AIE : 0); +} + +static int pcf8523_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *tm) +{ + struct pcf8523 *pcf8523 = dev_get_drvdata(dev); + u8 regs[5]; + int err; + + err = pcf8523_irq_enable(dev, 0); + if (err) + return err; + + err = regmap_write(pcf8523->regmap, PCF8523_REG_CONTROL2, 0); + if (err < 0) + return err; + + regs[0] = bin2bcd(tm->time.tm_min); + regs[1] = bin2bcd(tm->time.tm_hour); + regs[2] = bin2bcd(tm->time.tm_mday); + regs[3] = ALARM_DIS; + + err = regmap_bulk_write(pcf8523->regmap, PCF8523_REG_MINUTE_ALARM, regs, + sizeof(regs)); + if (err < 0) + return err; + + if (tm->enabled) + return pcf8523_irq_enable(dev, tm->enabled); + + return 0; +} + +static int pcf8523_param_get(struct device *dev, struct rtc_param *param) +{ + struct pcf8523 *pcf8523 = dev_get_drvdata(dev); + int ret; + u32 value; + + switch(param->param) { + + case RTC_PARAM_BACKUP_SWITCH_MODE: + ret = regmap_read(pcf8523->regmap, PCF8523_REG_CONTROL3, &value); + if (ret < 0) + return ret; + + value = FIELD_GET(PCF8523_CONTROL3_PM, value); + + switch(value) { + case 0x0: + case 0x4: + param->uvalue = RTC_BSM_LEVEL; + break; + case 0x1: + case 0x5: + param->uvalue = RTC_BSM_DIRECT; + break; + case PCF8523_PM_STANDBY: + param->uvalue = RTC_BSM_STANDBY; + break; + default: + param->uvalue = RTC_BSM_DISABLED; + } + + break; + + default: + return -EINVAL; + } + + return 0; +} + +static int pcf8523_param_set(struct device *dev, struct rtc_param *param) +{ + struct pcf8523 *pcf8523 = dev_get_drvdata(dev); + u8 mode; + + switch(param->param) { + case RTC_PARAM_BACKUP_SWITCH_MODE: + switch (param->uvalue) { + case RTC_BSM_DISABLED: + mode = 0x2; + break; + case RTC_BSM_DIRECT: + mode = 0x1; + break; + case RTC_BSM_LEVEL: + mode = 0x0; + break; + case RTC_BSM_STANDBY: + mode = PCF8523_PM_STANDBY; + break; + default: + return -EINVAL; + } + + return regmap_update_bits(pcf8523->regmap, PCF8523_REG_CONTROL3, + PCF8523_CONTROL3_PM, + FIELD_PREP(PCF8523_CONTROL3_PM, mode)); + + break; + + default: + return -EINVAL; + } + + return 0; +} + +static int pcf8523_rtc_ioctl(struct device *dev, unsigned int cmd, + unsigned long arg) +{ + struct pcf8523 *pcf8523 = dev_get_drvdata(dev); + unsigned int flags = 0; + u32 value; + int ret; + + switch (cmd) { + case RTC_VL_READ: + ret = regmap_read(pcf8523->regmap, PCF8523_REG_CONTROL3, &value); + if (ret < 0) + return ret; + + if (value & PCF8523_CONTROL3_BLF) + flags |= RTC_VL_BACKUP_LOW; + + ret = regmap_read(pcf8523->regmap, PCF8523_REG_SECONDS, &value); + if (ret < 0) + return ret; + + if (value & PCF8523_SECONDS_OS) + flags |= RTC_VL_DATA_INVALID; + + return put_user(flags, (unsigned int __user *)arg); + + default: + return -ENOIOCTLCMD; + } +} + +static int pcf8523_rtc_read_offset(struct device *dev, long *offset) +{ + struct pcf8523 *pcf8523 = dev_get_drvdata(dev); + int err; + u32 value; + s8 val; + + err = regmap_read(pcf8523->regmap, PCF8523_REG_OFFSET, &value); + if (err < 0) + return err; + + /* sign extend the 7-bit offset value */ + val = value << 1; + *offset = (value & PCF8523_OFFSET_MODE ? 4069 : 4340) * (val >> 1); + + return 0; +} + +static int pcf8523_rtc_set_offset(struct device *dev, long offset) +{ + struct pcf8523 *pcf8523 = dev_get_drvdata(dev); + long reg_m0, reg_m1; + u32 value; + + reg_m0 = clamp(DIV_ROUND_CLOSEST(offset, 4340), -64L, 63L); + reg_m1 = clamp(DIV_ROUND_CLOSEST(offset, 4069), -64L, 63L); + + if (abs(reg_m0 * 4340 - offset) < abs(reg_m1 * 4069 - offset)) + value = reg_m0 & 0x7f; + else + value = (reg_m1 & 0x7f) | PCF8523_OFFSET_MODE; + + return regmap_write(pcf8523->regmap, PCF8523_REG_OFFSET, value); +} + +static const struct rtc_class_ops pcf8523_rtc_ops = { + .read_time = pcf8523_rtc_read_time, + .set_time = pcf8523_rtc_set_time, + .read_alarm = pcf8523_rtc_read_alarm, + .set_alarm = pcf8523_rtc_set_alarm, + .alarm_irq_enable = pcf8523_irq_enable, + .ioctl = pcf8523_rtc_ioctl, + .read_offset = pcf8523_rtc_read_offset, + .set_offset = pcf8523_rtc_set_offset, + .param_get = pcf8523_param_get, + .param_set = pcf8523_param_set, +}; + +static const struct regmap_config regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = 0x13, +}; + +static int pcf8523_probe(struct i2c_client *client) +{ + struct pcf8523 *pcf8523; + struct rtc_device *rtc; + bool wakeup_source = false; + u32 value; + int err; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) + return -ENODEV; + + pcf8523 = devm_kzalloc(&client->dev, sizeof(struct pcf8523), GFP_KERNEL); + if (!pcf8523) + return -ENOMEM; + + pcf8523->regmap = devm_regmap_init_i2c(client, ®map_config); + if (IS_ERR(pcf8523->regmap)) + return PTR_ERR(pcf8523->regmap); + + i2c_set_clientdata(client, pcf8523); + + rtc = devm_rtc_allocate_device(&client->dev); + if (IS_ERR(rtc)) + return PTR_ERR(rtc); + pcf8523->rtc = rtc; + + err = pcf8523_load_capacitance(pcf8523, client->dev.of_node); + if (err < 0) + dev_warn(&client->dev, "failed to set xtal load capacitance: %d", + err); + + err = regmap_read(pcf8523->regmap, PCF8523_REG_SECONDS, &value); + if (err < 0) + return err; + + if (value & PCF8523_SECONDS_OS) { + err = regmap_read(pcf8523->regmap, PCF8523_REG_CONTROL3, &value); + if (err < 0) + return err; + + if (FIELD_GET(PCF8523_CONTROL3_PM, value) == PCF8523_PM_STANDBY) { + err = regmap_write(pcf8523->regmap, PCF8523_REG_CONTROL3, + value & ~PCF8523_CONTROL3_PM); + if (err < 0) + return err; + } + } + + rtc->ops = &pcf8523_rtc_ops; + rtc->range_min = RTC_TIMESTAMP_BEGIN_2000; + rtc->range_max = RTC_TIMESTAMP_END_2099; + set_bit(RTC_FEATURE_ALARM_RES_MINUTE, rtc->features); + clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, rtc->features); + + if (client->irq > 0) { + err = regmap_write(pcf8523->regmap, PCF8523_TMR_CLKOUT_CTRL, 0x38); + if (err < 0) + return err; + + err = devm_request_threaded_irq(&client->dev, client->irq, + NULL, pcf8523_irq, + IRQF_SHARED | IRQF_ONESHOT | IRQF_TRIGGER_LOW, + dev_name(&rtc->dev), pcf8523); + if (err) + return err; + + dev_pm_set_wake_irq(&client->dev, client->irq); + } + + wakeup_source = of_property_read_bool(client->dev.of_node, "wakeup-source"); + if (client->irq > 0 || wakeup_source) + device_init_wakeup(&client->dev, true); + + return devm_rtc_register_device(rtc); +} + +static const struct i2c_device_id pcf8523_id[] = { + { "pcf8523", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, pcf8523_id); + +static const struct of_device_id pcf8523_of_match[] = { + { .compatible = "nxp,pcf8523" }, + { .compatible = "microcrystal,rv8523" }, + { } +}; +MODULE_DEVICE_TABLE(of, pcf8523_of_match); + +static struct i2c_driver pcf8523_driver = { + .driver = { + .name = "rtc-pcf8523", + .of_match_table = pcf8523_of_match, + }, + .probe_new = pcf8523_probe, + .id_table = pcf8523_id, +}; +module_i2c_driver(pcf8523_driver); + +MODULE_AUTHOR("Thierry Reding "); +MODULE_DESCRIPTION("NXP PCF8523 RTC driver"); +MODULE_LICENSE("GPL v2"); -- cgit v1.2.3