| /* |
| * An I2C and SPI driver for the NXP PCF2127/29 RTC |
| * Copyright 2013 Til-Technologies |
| * |
| * Author: Renaud Cerrato <r.cerrato@til-technologies.fr> |
| * |
| * based on the other drivers in this same directory. |
| * |
| * Datasheet: http://cache.nxp.com/documents/data_sheet/PCF2127.pdf |
| * |
| * 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/i2c.h> |
| #include <linux/spi/spi.h> |
| #include <linux/bcd.h> |
| #include <linux/rtc.h> |
| #include <linux/slab.h> |
| #include <linux/module.h> |
| #include <linux/of.h> |
| #include <linux/regmap.h> |
| |
| #define PCF2127_REG_CTRL1 (0x00) /* Control Register 1 */ |
| #define PCF2127_REG_CTRL2 (0x01) /* Control Register 2 */ |
| |
| #define PCF2127_REG_CTRL3 (0x02) /* Control Register 3 */ |
| #define PCF2127_REG_CTRL3_BLF BIT(2) |
| |
| #define PCF2127_REG_SC (0x03) /* datetime */ |
| #define PCF2127_REG_MN (0x04) |
| #define PCF2127_REG_HR (0x05) |
| #define PCF2127_REG_DM (0x06) |
| #define PCF2127_REG_DW (0x07) |
| #define PCF2127_REG_MO (0x08) |
| #define PCF2127_REG_YR (0x09) |
| |
| #define PCF2127_OSF BIT(7) /* Oscillator Fail flag */ |
| |
| struct pcf2127 { |
| struct rtc_device *rtc; |
| struct regmap *regmap; |
| }; |
| |
| /* |
| * In the routines that deal directly with the pcf2127 hardware, we use |
| * rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch. |
| */ |
| static int pcf2127_rtc_read_time(struct device *dev, struct rtc_time *tm) |
| { |
| struct pcf2127 *pcf2127 = dev_get_drvdata(dev); |
| unsigned char buf[10]; |
| int ret; |
| |
| ret = regmap_bulk_read(pcf2127->regmap, PCF2127_REG_CTRL1, buf, |
| sizeof(buf)); |
| if (ret) { |
| dev_err(dev, "%s: read error\n", __func__); |
| return ret; |
| } |
| |
| if (buf[PCF2127_REG_CTRL3] & PCF2127_REG_CTRL3_BLF) |
| dev_info(dev, |
| "low voltage detected, check/replace RTC battery.\n"); |
| |
| if (buf[PCF2127_REG_SC] & PCF2127_OSF) { |
| /* |
| * no need clear the flag here, |
| * it will be cleared once the new date is saved |
| */ |
| dev_warn(dev, |
| "oscillator stop detected, date/time is not reliable\n"); |
| return -EINVAL; |
| } |
| |
| dev_dbg(dev, |
| "%s: raw data is cr1=%02x, cr2=%02x, cr3=%02x, " |
| "sec=%02x, min=%02x, hr=%02x, " |
| "mday=%02x, wday=%02x, mon=%02x, year=%02x\n", |
| __func__, |
| buf[0], buf[1], buf[2], |
| buf[3], buf[4], buf[5], |
| buf[6], buf[7], buf[8], buf[9]); |
| |
| |
| tm->tm_sec = bcd2bin(buf[PCF2127_REG_SC] & 0x7F); |
| tm->tm_min = bcd2bin(buf[PCF2127_REG_MN] & 0x7F); |
| tm->tm_hour = bcd2bin(buf[PCF2127_REG_HR] & 0x3F); /* rtc hr 0-23 */ |
| tm->tm_mday = bcd2bin(buf[PCF2127_REG_DM] & 0x3F); |
| tm->tm_wday = buf[PCF2127_REG_DW] & 0x07; |
| tm->tm_mon = bcd2bin(buf[PCF2127_REG_MO] & 0x1F) - 1; /* rtc mn 1-12 */ |
| tm->tm_year = bcd2bin(buf[PCF2127_REG_YR]); |
| if (tm->tm_year < 70) |
| tm->tm_year += 100; /* assume we are in 1970...2069 */ |
| |
| dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, " |
| "mday=%d, mon=%d, year=%d, wday=%d\n", |
| __func__, |
| tm->tm_sec, tm->tm_min, tm->tm_hour, |
| tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); |
| |
| return rtc_valid_tm(tm); |
| } |
| |
| static int pcf2127_rtc_set_time(struct device *dev, struct rtc_time *tm) |
| { |
| struct pcf2127 *pcf2127 = dev_get_drvdata(dev); |
| unsigned char buf[7]; |
| int i = 0, err; |
| |
| dev_dbg(dev, "%s: secs=%d, mins=%d, hours=%d, " |
| "mday=%d, mon=%d, year=%d, wday=%d\n", |
| __func__, |
| tm->tm_sec, tm->tm_min, tm->tm_hour, |
| tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); |
| |
| /* hours, minutes and seconds */ |
| buf[i++] = bin2bcd(tm->tm_sec); /* this will also clear OSF flag */ |
| buf[i++] = bin2bcd(tm->tm_min); |
| buf[i++] = bin2bcd(tm->tm_hour); |
| buf[i++] = bin2bcd(tm->tm_mday); |
| buf[i++] = tm->tm_wday & 0x07; |
| |
| /* month, 1 - 12 */ |
| buf[i++] = bin2bcd(tm->tm_mon + 1); |
| |
| /* year */ |
| buf[i++] = bin2bcd(tm->tm_year % 100); |
| |
| /* write register's data */ |
| err = regmap_bulk_write(pcf2127->regmap, PCF2127_REG_SC, buf, i); |
| if (err) { |
| dev_err(dev, |
| "%s: err=%d", __func__, err); |
| return err; |
| } |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_RTC_INTF_DEV |
| static int pcf2127_rtc_ioctl(struct device *dev, |
| unsigned int cmd, unsigned long arg) |
| { |
| struct pcf2127 *pcf2127 = dev_get_drvdata(dev); |
| int touser; |
| int ret; |
| |
| switch (cmd) { |
| case RTC_VL_READ: |
| ret = regmap_read(pcf2127->regmap, PCF2127_REG_CTRL3, &touser); |
| if (ret) |
| return ret; |
| |
| touser = touser & PCF2127_REG_CTRL3_BLF ? 1 : 0; |
| |
| if (copy_to_user((void __user *)arg, &touser, sizeof(int))) |
| return -EFAULT; |
| return 0; |
| default: |
| return -ENOIOCTLCMD; |
| } |
| } |
| #else |
| #define pcf2127_rtc_ioctl NULL |
| #endif |
| |
| static const struct rtc_class_ops pcf2127_rtc_ops = { |
| .ioctl = pcf2127_rtc_ioctl, |
| .read_time = pcf2127_rtc_read_time, |
| .set_time = pcf2127_rtc_set_time, |
| }; |
| |
| static int pcf2127_probe(struct device *dev, struct regmap *regmap, |
| const char *name) |
| { |
| struct pcf2127 *pcf2127; |
| |
| dev_dbg(dev, "%s\n", __func__); |
| |
| pcf2127 = devm_kzalloc(dev, sizeof(*pcf2127), GFP_KERNEL); |
| if (!pcf2127) |
| return -ENOMEM; |
| |
| pcf2127->regmap = regmap; |
| |
| dev_set_drvdata(dev, pcf2127); |
| |
| pcf2127->rtc = devm_rtc_device_register(dev, name, &pcf2127_rtc_ops, |
| THIS_MODULE); |
| |
| return PTR_ERR_OR_ZERO(pcf2127->rtc); |
| } |
| |
| #ifdef CONFIG_OF |
| static const struct of_device_id pcf2127_of_match[] = { |
| { .compatible = "nxp,pcf2127" }, |
| { .compatible = "nxp,pcf2129" }, |
| {} |
| }; |
| MODULE_DEVICE_TABLE(of, pcf2127_of_match); |
| #endif |
| |
| #if IS_ENABLED(CONFIG_I2C) |
| |
| static int pcf2127_i2c_write(void *context, const void *data, size_t count) |
| { |
| struct device *dev = context; |
| struct i2c_client *client = to_i2c_client(dev); |
| int ret; |
| |
| ret = i2c_master_send(client, data, count); |
| if (ret != count) |
| return ret < 0 ? ret : -EIO; |
| |
| return 0; |
| } |
| |
| static int pcf2127_i2c_gather_write(void *context, |
| const void *reg, size_t reg_size, |
| const void *val, size_t val_size) |
| { |
| struct device *dev = context; |
| struct i2c_client *client = to_i2c_client(dev); |
| int ret; |
| void *buf; |
| |
| if (WARN_ON(reg_size != 1)) |
| return -EINVAL; |
| |
| buf = kmalloc(val_size + 1, GFP_KERNEL); |
| if (!buf) |
| return -ENOMEM; |
| |
| memcpy(buf, reg, 1); |
| memcpy(buf + 1, val, val_size); |
| |
| ret = i2c_master_send(client, buf, val_size + 1); |
| |
| kfree(buf); |
| |
| if (ret != val_size + 1) |
| return ret < 0 ? ret : -EIO; |
| |
| return 0; |
| } |
| |
| static int pcf2127_i2c_read(void *context, const void *reg, size_t reg_size, |
| void *val, size_t val_size) |
| { |
| struct device *dev = context; |
| struct i2c_client *client = to_i2c_client(dev); |
| int ret; |
| |
| if (WARN_ON(reg_size != 1)) |
| return -EINVAL; |
| |
| ret = i2c_master_send(client, reg, 1); |
| if (ret != 1) |
| return ret < 0 ? ret : -EIO; |
| |
| ret = i2c_master_recv(client, val, val_size); |
| if (ret != val_size) |
| return ret < 0 ? ret : -EIO; |
| |
| return 0; |
| } |
| |
| /* |
| * The reason we need this custom regmap_bus instead of using regmap_init_i2c() |
| * is that the STOP condition is required between set register address and |
| * read register data when reading from registers. |
| */ |
| static const struct regmap_bus pcf2127_i2c_regmap = { |
| .write = pcf2127_i2c_write, |
| .gather_write = pcf2127_i2c_gather_write, |
| .read = pcf2127_i2c_read, |
| }; |
| |
| static struct i2c_driver pcf2127_i2c_driver; |
| |
| static int pcf2127_i2c_probe(struct i2c_client *client, |
| const struct i2c_device_id *id) |
| { |
| struct regmap *regmap; |
| static const struct regmap_config config = { |
| .reg_bits = 8, |
| .val_bits = 8, |
| }; |
| |
| if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) |
| return -ENODEV; |
| |
| regmap = devm_regmap_init(&client->dev, &pcf2127_i2c_regmap, |
| &client->dev, &config); |
| if (IS_ERR(regmap)) { |
| dev_err(&client->dev, "%s: regmap allocation failed: %ld\n", |
| __func__, PTR_ERR(regmap)); |
| return PTR_ERR(regmap); |
| } |
| |
| return pcf2127_probe(&client->dev, regmap, |
| pcf2127_i2c_driver.driver.name); |
| } |
| |
| static const struct i2c_device_id pcf2127_i2c_id[] = { |
| { "pcf2127", 0 }, |
| { "pcf2129", 0 }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(i2c, pcf2127_i2c_id); |
| |
| static struct i2c_driver pcf2127_i2c_driver = { |
| .driver = { |
| .name = "rtc-pcf2127-i2c", |
| .of_match_table = of_match_ptr(pcf2127_of_match), |
| }, |
| .probe = pcf2127_i2c_probe, |
| .id_table = pcf2127_i2c_id, |
| }; |
| |
| static int pcf2127_i2c_register_driver(void) |
| { |
| return i2c_add_driver(&pcf2127_i2c_driver); |
| } |
| |
| static void pcf2127_i2c_unregister_driver(void) |
| { |
| i2c_del_driver(&pcf2127_i2c_driver); |
| } |
| |
| #else |
| |
| static int pcf2127_i2c_register_driver(void) |
| { |
| return 0; |
| } |
| |
| static void pcf2127_i2c_unregister_driver(void) |
| { |
| } |
| |
| #endif |
| |
| #if IS_ENABLED(CONFIG_SPI_MASTER) |
| |
| static struct spi_driver pcf2127_spi_driver; |
| |
| static int pcf2127_spi_probe(struct spi_device *spi) |
| { |
| static const struct regmap_config config = { |
| .reg_bits = 8, |
| .val_bits = 8, |
| .read_flag_mask = 0xa0, |
| .write_flag_mask = 0x20, |
| }; |
| struct regmap *regmap; |
| |
| regmap = devm_regmap_init_spi(spi, &config); |
| if (IS_ERR(regmap)) { |
| dev_err(&spi->dev, "%s: regmap allocation failed: %ld\n", |
| __func__, PTR_ERR(regmap)); |
| return PTR_ERR(regmap); |
| } |
| |
| return pcf2127_probe(&spi->dev, regmap, pcf2127_spi_driver.driver.name); |
| } |
| |
| static const struct spi_device_id pcf2127_spi_id[] = { |
| { "pcf2127", 0 }, |
| { "pcf2129", 0 }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(spi, pcf2127_spi_id); |
| |
| static struct spi_driver pcf2127_spi_driver = { |
| .driver = { |
| .name = "rtc-pcf2127-spi", |
| .of_match_table = of_match_ptr(pcf2127_of_match), |
| }, |
| .probe = pcf2127_spi_probe, |
| .id_table = pcf2127_spi_id, |
| }; |
| |
| static int pcf2127_spi_register_driver(void) |
| { |
| return spi_register_driver(&pcf2127_spi_driver); |
| } |
| |
| static void pcf2127_spi_unregister_driver(void) |
| { |
| spi_unregister_driver(&pcf2127_spi_driver); |
| } |
| |
| #else |
| |
| static int pcf2127_spi_register_driver(void) |
| { |
| return 0; |
| } |
| |
| static void pcf2127_spi_unregister_driver(void) |
| { |
| } |
| |
| #endif |
| |
| static int __init pcf2127_init(void) |
| { |
| int ret; |
| |
| ret = pcf2127_i2c_register_driver(); |
| if (ret) { |
| pr_err("Failed to register pcf2127 i2c driver: %d\n", ret); |
| return ret; |
| } |
| |
| ret = pcf2127_spi_register_driver(); |
| if (ret) { |
| pr_err("Failed to register pcf2127 spi driver: %d\n", ret); |
| pcf2127_i2c_unregister_driver(); |
| } |
| |
| return ret; |
| } |
| module_init(pcf2127_init) |
| |
| static void __exit pcf2127_exit(void) |
| { |
| pcf2127_spi_unregister_driver(); |
| pcf2127_i2c_unregister_driver(); |
| } |
| module_exit(pcf2127_exit) |
| |
| MODULE_AUTHOR("Renaud Cerrato <r.cerrato@til-technologies.fr>"); |
| MODULE_DESCRIPTION("NXP PCF2127/29 RTC driver"); |
| MODULE_LICENSE("GPL v2"); |