diff options
Diffstat (limited to 'drivers/rtc/rtc-isl1208.c')
| -rw-r--r-- | drivers/rtc/rtc-isl1208.c | 917 |
1 files changed, 917 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-isl1208.c b/drivers/rtc/rtc-isl1208.c new file mode 100644 index 000000000..f448a5253 --- /dev/null +++ b/drivers/rtc/rtc-isl1208.c @@ -0,0 +1,917 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Intersil ISL1208 rtc class driver + * + * Copyright 2005,2006 Hebert Valerio Riedel <hvr@gnu.org> + */ + +#include <linux/bcd.h> +#include <linux/i2c.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/of_irq.h> +#include <linux/rtc.h> + +/* Register map */ +/* rtc section */ +#define ISL1208_REG_SC 0x00 +#define ISL1208_REG_MN 0x01 +#define ISL1208_REG_HR 0x02 +#define ISL1208_REG_HR_MIL (1<<7) /* 24h/12h mode */ +#define ISL1208_REG_HR_PM (1<<5) /* PM/AM bit in 12h mode */ +#define ISL1208_REG_DT 0x03 +#define ISL1208_REG_MO 0x04 +#define ISL1208_REG_YR 0x05 +#define ISL1208_REG_DW 0x06 +#define ISL1208_RTC_SECTION_LEN 7 + +/* control/status section */ +#define ISL1208_REG_SR 0x07 +#define ISL1208_REG_SR_ARST (1<<7) /* auto reset */ +#define ISL1208_REG_SR_XTOSCB (1<<6) /* crystal oscillator */ +#define ISL1208_REG_SR_WRTC (1<<4) /* write rtc */ +#define ISL1208_REG_SR_EVT (1<<3) /* event */ +#define ISL1208_REG_SR_ALM (1<<2) /* alarm */ +#define ISL1208_REG_SR_BAT (1<<1) /* battery */ +#define ISL1208_REG_SR_RTCF (1<<0) /* rtc fail */ +#define ISL1208_REG_INT 0x08 +#define ISL1208_REG_INT_ALME (1<<6) /* alarm enable */ +#define ISL1208_REG_INT_IM (1<<7) /* interrupt/alarm mode */ +#define ISL1219_REG_EV 0x09 +#define ISL1219_REG_EV_EVEN (1<<4) /* event detection enable */ +#define ISL1219_REG_EV_EVIENB (1<<7) /* event in pull-up disable */ +#define ISL1208_REG_ATR 0x0a +#define ISL1208_REG_DTR 0x0b + +/* alarm section */ +#define ISL1208_REG_SCA 0x0c +#define ISL1208_REG_MNA 0x0d +#define ISL1208_REG_HRA 0x0e +#define ISL1208_REG_DTA 0x0f +#define ISL1208_REG_MOA 0x10 +#define ISL1208_REG_DWA 0x11 +#define ISL1208_ALARM_SECTION_LEN 6 + +/* user section */ +#define ISL1208_REG_USR1 0x12 +#define ISL1208_REG_USR2 0x13 +#define ISL1208_USR_SECTION_LEN 2 + +/* event section */ +#define ISL1219_REG_SCT 0x14 +#define ISL1219_REG_MNT 0x15 +#define ISL1219_REG_HRT 0x16 +#define ISL1219_REG_DTT 0x17 +#define ISL1219_REG_MOT 0x18 +#define ISL1219_REG_YRT 0x19 +#define ISL1219_EVT_SECTION_LEN 6 + +static struct i2c_driver isl1208_driver; + +/* ISL1208 various variants */ +enum isl1208_id { + TYPE_ISL1208 = 0, + TYPE_ISL1209, + TYPE_ISL1218, + TYPE_ISL1219, + ISL_LAST_ID +}; + +/* Chip capabilities table */ +static const struct isl1208_config { + const char name[8]; + unsigned int nvmem_length; + unsigned has_tamper:1; + unsigned has_timestamp:1; +} isl1208_configs[] = { + [TYPE_ISL1208] = { "isl1208", 2, false, false }, + [TYPE_ISL1209] = { "isl1209", 2, true, false }, + [TYPE_ISL1218] = { "isl1218", 8, false, false }, + [TYPE_ISL1219] = { "isl1219", 2, true, true }, +}; + +static const struct i2c_device_id isl1208_id[] = { + { "isl1208", TYPE_ISL1208 }, + { "isl1209", TYPE_ISL1209 }, + { "isl1218", TYPE_ISL1218 }, + { "isl1219", TYPE_ISL1219 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, isl1208_id); + +static const __maybe_unused struct of_device_id isl1208_of_match[] = { + { .compatible = "isil,isl1208", .data = &isl1208_configs[TYPE_ISL1208] }, + { .compatible = "isil,isl1209", .data = &isl1208_configs[TYPE_ISL1209] }, + { .compatible = "isil,isl1218", .data = &isl1208_configs[TYPE_ISL1218] }, + { .compatible = "isil,isl1219", .data = &isl1208_configs[TYPE_ISL1219] }, + { } +}; +MODULE_DEVICE_TABLE(of, isl1208_of_match); + +/* Device state */ +struct isl1208_state { + struct nvmem_config nvmem_config; + struct rtc_device *rtc; + const struct isl1208_config *config; +}; + +/* block read */ +static int +isl1208_i2c_read_regs(struct i2c_client *client, u8 reg, u8 buf[], + unsigned len) +{ + int ret; + + WARN_ON(reg > ISL1219_REG_YRT); + WARN_ON(reg + len > ISL1219_REG_YRT + 1); + + ret = i2c_smbus_read_i2c_block_data(client, reg, len, buf); + return (ret < 0) ? ret : 0; +} + +/* block write */ +static int +isl1208_i2c_set_regs(struct i2c_client *client, u8 reg, u8 const buf[], + unsigned len) +{ + int ret; + + WARN_ON(reg > ISL1219_REG_YRT); + WARN_ON(reg + len > ISL1219_REG_YRT + 1); + + ret = i2c_smbus_write_i2c_block_data(client, reg, len, buf); + return (ret < 0) ? ret : 0; +} + +/* simple check to see whether we have a isl1208 */ +static int +isl1208_i2c_validate_client(struct i2c_client *client) +{ + u8 regs[ISL1208_RTC_SECTION_LEN] = { 0, }; + u8 zero_mask[ISL1208_RTC_SECTION_LEN] = { + 0x80, 0x80, 0x40, 0xc0, 0xe0, 0x00, 0xf8 + }; + int i; + int ret; + + ret = isl1208_i2c_read_regs(client, 0, regs, ISL1208_RTC_SECTION_LEN); + if (ret < 0) + return ret; + + for (i = 0; i < ISL1208_RTC_SECTION_LEN; ++i) { + if (regs[i] & zero_mask[i]) /* check if bits are cleared */ + return -ENODEV; + } + + return 0; +} + +static int +isl1208_i2c_get_sr(struct i2c_client *client) +{ + return i2c_smbus_read_byte_data(client, ISL1208_REG_SR); +} + +static int +isl1208_i2c_get_atr(struct i2c_client *client) +{ + int atr = i2c_smbus_read_byte_data(client, ISL1208_REG_ATR); + if (atr < 0) + return atr; + + /* The 6bit value in the ATR register controls the load + * capacitance C_load * in steps of 0.25pF + * + * bit (1<<5) of the ATR register is inverted + * + * C_load(ATR=0x20) = 4.50pF + * C_load(ATR=0x00) = 12.50pF + * C_load(ATR=0x1f) = 20.25pF + * + */ + + atr &= 0x3f; /* mask out lsb */ + atr ^= 1 << 5; /* invert 6th bit */ + atr += 2 * 9; /* add offset of 4.5pF; unit[atr] = 0.25pF */ + + return atr; +} + +/* returns adjustment value + 100 */ +static int +isl1208_i2c_get_dtr(struct i2c_client *client) +{ + int dtr = i2c_smbus_read_byte_data(client, ISL1208_REG_DTR); + if (dtr < 0) + return -EIO; + + /* dtr encodes adjustments of {-60,-40,-20,0,20,40,60} ppm */ + dtr = ((dtr & 0x3) * 20) * (dtr & (1 << 2) ? -1 : 1); + + return dtr + 100; +} + +static int +isl1208_i2c_get_usr(struct i2c_client *client) +{ + u8 buf[ISL1208_USR_SECTION_LEN] = { 0, }; + int ret; + + ret = isl1208_i2c_read_regs(client, ISL1208_REG_USR1, buf, + ISL1208_USR_SECTION_LEN); + if (ret < 0) + return ret; + + return (buf[1] << 8) | buf[0]; +} + +static int +isl1208_i2c_set_usr(struct i2c_client *client, u16 usr) +{ + u8 buf[ISL1208_USR_SECTION_LEN]; + + buf[0] = usr & 0xff; + buf[1] = (usr >> 8) & 0xff; + + return isl1208_i2c_set_regs(client, ISL1208_REG_USR1, buf, + ISL1208_USR_SECTION_LEN); +} + +static int +isl1208_rtc_toggle_alarm(struct i2c_client *client, int enable) +{ + int icr = i2c_smbus_read_byte_data(client, ISL1208_REG_INT); + + if (icr < 0) { + dev_err(&client->dev, "%s: reading INT failed\n", __func__); + return icr; + } + + if (enable) + icr |= ISL1208_REG_INT_ALME | ISL1208_REG_INT_IM; + else + icr &= ~(ISL1208_REG_INT_ALME | ISL1208_REG_INT_IM); + + icr = i2c_smbus_write_byte_data(client, ISL1208_REG_INT, icr); + if (icr < 0) { + dev_err(&client->dev, "%s: writing INT failed\n", __func__); + return icr; + } + + return 0; +} + +static int +isl1208_rtc_proc(struct device *dev, struct seq_file *seq) +{ + struct i2c_client *const client = to_i2c_client(dev); + int sr, dtr, atr, usr; + + sr = isl1208_i2c_get_sr(client); + if (sr < 0) { + dev_err(&client->dev, "%s: reading SR failed\n", __func__); + return sr; + } + + seq_printf(seq, "status_reg\t:%s%s%s%s%s%s (0x%.2x)\n", + (sr & ISL1208_REG_SR_RTCF) ? " RTCF" : "", + (sr & ISL1208_REG_SR_BAT) ? " BAT" : "", + (sr & ISL1208_REG_SR_ALM) ? " ALM" : "", + (sr & ISL1208_REG_SR_WRTC) ? " WRTC" : "", + (sr & ISL1208_REG_SR_XTOSCB) ? " XTOSCB" : "", + (sr & ISL1208_REG_SR_ARST) ? " ARST" : "", sr); + + seq_printf(seq, "batt_status\t: %s\n", + (sr & ISL1208_REG_SR_RTCF) ? "bad" : "okay"); + + dtr = isl1208_i2c_get_dtr(client); + if (dtr >= 0) + seq_printf(seq, "digital_trim\t: %d ppm\n", dtr - 100); + + atr = isl1208_i2c_get_atr(client); + if (atr >= 0) + seq_printf(seq, "analog_trim\t: %d.%.2d pF\n", + atr >> 2, (atr & 0x3) * 25); + + usr = isl1208_i2c_get_usr(client); + if (usr >= 0) + seq_printf(seq, "user_data\t: 0x%.4x\n", usr); + + return 0; +} + +static int +isl1208_i2c_read_time(struct i2c_client *client, struct rtc_time *tm) +{ + int sr; + u8 regs[ISL1208_RTC_SECTION_LEN] = { 0, }; + + sr = isl1208_i2c_get_sr(client); + if (sr < 0) { + dev_err(&client->dev, "%s: reading SR failed\n", __func__); + return -EIO; + } + + sr = isl1208_i2c_read_regs(client, 0, regs, ISL1208_RTC_SECTION_LEN); + if (sr < 0) { + dev_err(&client->dev, "%s: reading RTC section failed\n", + __func__); + return sr; + } + + tm->tm_sec = bcd2bin(regs[ISL1208_REG_SC]); + tm->tm_min = bcd2bin(regs[ISL1208_REG_MN]); + + /* HR field has a more complex interpretation */ + { + const u8 _hr = regs[ISL1208_REG_HR]; + if (_hr & ISL1208_REG_HR_MIL) /* 24h format */ + tm->tm_hour = bcd2bin(_hr & 0x3f); + else { + /* 12h format */ + tm->tm_hour = bcd2bin(_hr & 0x1f); + if (_hr & ISL1208_REG_HR_PM) /* PM flag set */ + tm->tm_hour += 12; + } + } + + tm->tm_mday = bcd2bin(regs[ISL1208_REG_DT]); + tm->tm_mon = bcd2bin(regs[ISL1208_REG_MO]) - 1; /* rtc starts at 1 */ + tm->tm_year = bcd2bin(regs[ISL1208_REG_YR]) + 100; + tm->tm_wday = bcd2bin(regs[ISL1208_REG_DW]); + + return 0; +} + +static int +isl1208_i2c_read_alarm(struct i2c_client *client, struct rtc_wkalrm *alarm) +{ + struct rtc_time *const tm = &alarm->time; + u8 regs[ISL1208_ALARM_SECTION_LEN] = { 0, }; + int icr, yr, sr = isl1208_i2c_get_sr(client); + + if (sr < 0) { + dev_err(&client->dev, "%s: reading SR failed\n", __func__); + return sr; + } + + sr = isl1208_i2c_read_regs(client, ISL1208_REG_SCA, regs, + ISL1208_ALARM_SECTION_LEN); + if (sr < 0) { + dev_err(&client->dev, "%s: reading alarm section failed\n", + __func__); + return sr; + } + + /* MSB of each alarm register is an enable bit */ + tm->tm_sec = bcd2bin(regs[ISL1208_REG_SCA - ISL1208_REG_SCA] & 0x7f); + tm->tm_min = bcd2bin(regs[ISL1208_REG_MNA - ISL1208_REG_SCA] & 0x7f); + tm->tm_hour = bcd2bin(regs[ISL1208_REG_HRA - ISL1208_REG_SCA] & 0x3f); + tm->tm_mday = bcd2bin(regs[ISL1208_REG_DTA - ISL1208_REG_SCA] & 0x3f); + tm->tm_mon = + bcd2bin(regs[ISL1208_REG_MOA - ISL1208_REG_SCA] & 0x1f) - 1; + tm->tm_wday = bcd2bin(regs[ISL1208_REG_DWA - ISL1208_REG_SCA] & 0x03); + + /* The alarm doesn't store the year so get it from the rtc section */ + yr = i2c_smbus_read_byte_data(client, ISL1208_REG_YR); + if (yr < 0) { + dev_err(&client->dev, "%s: reading RTC YR failed\n", __func__); + return yr; + } + tm->tm_year = bcd2bin(yr) + 100; + + icr = i2c_smbus_read_byte_data(client, ISL1208_REG_INT); + if (icr < 0) { + dev_err(&client->dev, "%s: reading INT failed\n", __func__); + return icr; + } + alarm->enabled = !!(icr & ISL1208_REG_INT_ALME); + + return 0; +} + +static int +isl1208_i2c_set_alarm(struct i2c_client *client, struct rtc_wkalrm *alarm) +{ + struct rtc_time *alarm_tm = &alarm->time; + u8 regs[ISL1208_ALARM_SECTION_LEN] = { 0, }; + const int offs = ISL1208_REG_SCA; + struct rtc_time rtc_tm; + int err, enable; + + err = isl1208_i2c_read_time(client, &rtc_tm); + if (err) + return err; + + /* If the alarm time is before the current time disable the alarm */ + if (!alarm->enabled || rtc_tm_sub(alarm_tm, &rtc_tm) <= 0) + enable = 0x00; + else + enable = 0x80; + + /* Program the alarm and enable it for each setting */ + regs[ISL1208_REG_SCA - offs] = bin2bcd(alarm_tm->tm_sec) | enable; + regs[ISL1208_REG_MNA - offs] = bin2bcd(alarm_tm->tm_min) | enable; + regs[ISL1208_REG_HRA - offs] = bin2bcd(alarm_tm->tm_hour) | + ISL1208_REG_HR_MIL | enable; + + regs[ISL1208_REG_DTA - offs] = bin2bcd(alarm_tm->tm_mday) | enable; + regs[ISL1208_REG_MOA - offs] = bin2bcd(alarm_tm->tm_mon + 1) | enable; + regs[ISL1208_REG_DWA - offs] = bin2bcd(alarm_tm->tm_wday & 7) | enable; + + /* write ALARM registers */ + err = isl1208_i2c_set_regs(client, offs, regs, + ISL1208_ALARM_SECTION_LEN); + if (err < 0) { + dev_err(&client->dev, "%s: writing ALARM section failed\n", + __func__); + return err; + } + + err = isl1208_rtc_toggle_alarm(client, enable); + if (err) + return err; + + return 0; +} + +static int +isl1208_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + return isl1208_i2c_read_time(to_i2c_client(dev), tm); +} + +static int +isl1208_i2c_set_time(struct i2c_client *client, struct rtc_time const *tm) +{ + int sr; + u8 regs[ISL1208_RTC_SECTION_LEN] = { 0, }; + + /* The clock has an 8 bit wide bcd-coded register (they never learn) + * for the year. tm_year is an offset from 1900 and we are interested + * in the 2000-2099 range, so any value less than 100 is invalid. + */ + if (tm->tm_year < 100) + return -EINVAL; + + regs[ISL1208_REG_SC] = bin2bcd(tm->tm_sec); + regs[ISL1208_REG_MN] = bin2bcd(tm->tm_min); + regs[ISL1208_REG_HR] = bin2bcd(tm->tm_hour) | ISL1208_REG_HR_MIL; + + regs[ISL1208_REG_DT] = bin2bcd(tm->tm_mday); + regs[ISL1208_REG_MO] = bin2bcd(tm->tm_mon + 1); + regs[ISL1208_REG_YR] = bin2bcd(tm->tm_year - 100); + + regs[ISL1208_REG_DW] = bin2bcd(tm->tm_wday & 7); + + sr = isl1208_i2c_get_sr(client); + if (sr < 0) { + dev_err(&client->dev, "%s: reading SR failed\n", __func__); + return sr; + } + + /* set WRTC */ + sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR, + sr | ISL1208_REG_SR_WRTC); + if (sr < 0) { + dev_err(&client->dev, "%s: writing SR failed\n", __func__); + return sr; + } + + /* write RTC registers */ + sr = isl1208_i2c_set_regs(client, 0, regs, ISL1208_RTC_SECTION_LEN); + if (sr < 0) { + dev_err(&client->dev, "%s: writing RTC section failed\n", + __func__); + return sr; + } + + /* clear WRTC again */ + sr = isl1208_i2c_get_sr(client); + if (sr < 0) { + dev_err(&client->dev, "%s: reading SR failed\n", __func__); + return sr; + } + sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR, + sr & ~ISL1208_REG_SR_WRTC); + if (sr < 0) { + dev_err(&client->dev, "%s: writing SR failed\n", __func__); + return sr; + } + + return 0; +} + + +static int +isl1208_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + return isl1208_i2c_set_time(to_i2c_client(dev), tm); +} + +static int +isl1208_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) +{ + return isl1208_i2c_read_alarm(to_i2c_client(dev), alarm); +} + +static int +isl1208_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) +{ + return isl1208_i2c_set_alarm(to_i2c_client(dev), alarm); +} + +static ssize_t timestamp0_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct i2c_client *client = to_i2c_client(dev->parent); + int sr; + + sr = isl1208_i2c_get_sr(client); + if (sr < 0) { + dev_err(dev, "%s: reading SR failed\n", __func__); + return sr; + } + + sr &= ~ISL1208_REG_SR_EVT; + + sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR, sr); + if (sr < 0) + dev_err(dev, "%s: writing SR failed\n", + __func__); + + return count; +}; + +static ssize_t timestamp0_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct i2c_client *client = to_i2c_client(dev->parent); + u8 regs[ISL1219_EVT_SECTION_LEN] = { 0, }; + struct rtc_time tm; + int sr; + + sr = isl1208_i2c_get_sr(client); + if (sr < 0) { + dev_err(dev, "%s: reading SR failed\n", __func__); + return sr; + } + + if (!(sr & ISL1208_REG_SR_EVT)) + return 0; + + sr = isl1208_i2c_read_regs(client, ISL1219_REG_SCT, regs, + ISL1219_EVT_SECTION_LEN); + if (sr < 0) { + dev_err(dev, "%s: reading event section failed\n", + __func__); + return 0; + } + + /* MSB of each alarm register is an enable bit */ + tm.tm_sec = bcd2bin(regs[ISL1219_REG_SCT - ISL1219_REG_SCT] & 0x7f); + tm.tm_min = bcd2bin(regs[ISL1219_REG_MNT - ISL1219_REG_SCT] & 0x7f); + tm.tm_hour = bcd2bin(regs[ISL1219_REG_HRT - ISL1219_REG_SCT] & 0x3f); + tm.tm_mday = bcd2bin(regs[ISL1219_REG_DTT - ISL1219_REG_SCT] & 0x3f); + tm.tm_mon = + bcd2bin(regs[ISL1219_REG_MOT - ISL1219_REG_SCT] & 0x1f) - 1; + tm.tm_year = bcd2bin(regs[ISL1219_REG_YRT - ISL1219_REG_SCT]) + 100; + + sr = rtc_valid_tm(&tm); + if (sr) + return sr; + + return sprintf(buf, "%llu\n", + (unsigned long long)rtc_tm_to_time64(&tm)); +}; + +static DEVICE_ATTR_RW(timestamp0); + +static irqreturn_t +isl1208_rtc_interrupt(int irq, void *data) +{ + unsigned long timeout = jiffies + msecs_to_jiffies(1000); + struct i2c_client *client = data; + struct isl1208_state *isl1208 = i2c_get_clientdata(client); + int handled = 0, sr, err; + + /* + * I2C reads get NAK'ed if we read straight away after an interrupt? + * Using a mdelay/msleep didn't seem to help either, so we work around + * this by continually trying to read the register for a short time. + */ + while (1) { + sr = isl1208_i2c_get_sr(client); + if (sr >= 0) + break; + + if (time_after(jiffies, timeout)) { + dev_err(&client->dev, "%s: reading SR failed\n", + __func__); + return sr; + } + } + + if (sr & ISL1208_REG_SR_ALM) { + dev_dbg(&client->dev, "alarm!\n"); + + rtc_update_irq(isl1208->rtc, 1, RTC_IRQF | RTC_AF); + + /* Clear the alarm */ + sr &= ~ISL1208_REG_SR_ALM; + sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR, sr); + if (sr < 0) + dev_err(&client->dev, "%s: writing SR failed\n", + __func__); + else + handled = 1; + + /* Disable the alarm */ + err = isl1208_rtc_toggle_alarm(client, 0); + if (err) + return err; + } + + if (isl1208->config->has_tamper && (sr & ISL1208_REG_SR_EVT)) { + dev_warn(&client->dev, "event detected"); + handled = 1; + if (isl1208->config->has_timestamp) + sysfs_notify(&isl1208->rtc->dev.kobj, NULL, + dev_attr_timestamp0.attr.name); + } + + return handled ? IRQ_HANDLED : IRQ_NONE; +} + +static const struct rtc_class_ops isl1208_rtc_ops = { + .proc = isl1208_rtc_proc, + .read_time = isl1208_rtc_read_time, + .set_time = isl1208_rtc_set_time, + .read_alarm = isl1208_rtc_read_alarm, + .set_alarm = isl1208_rtc_set_alarm, +}; + +/* sysfs interface */ + +static ssize_t +isl1208_sysfs_show_atrim(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int atr = isl1208_i2c_get_atr(to_i2c_client(dev->parent)); + if (atr < 0) + return atr; + + return sprintf(buf, "%d.%.2d pF\n", atr >> 2, (atr & 0x3) * 25); +} + +static DEVICE_ATTR(atrim, S_IRUGO, isl1208_sysfs_show_atrim, NULL); + +static ssize_t +isl1208_sysfs_show_dtrim(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int dtr = isl1208_i2c_get_dtr(to_i2c_client(dev->parent)); + if (dtr < 0) + return dtr; + + return sprintf(buf, "%d ppm\n", dtr - 100); +} + +static DEVICE_ATTR(dtrim, S_IRUGO, isl1208_sysfs_show_dtrim, NULL); + +static ssize_t +isl1208_sysfs_show_usr(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int usr = isl1208_i2c_get_usr(to_i2c_client(dev->parent)); + if (usr < 0) + return usr; + + return sprintf(buf, "0x%.4x\n", usr); +} + +static ssize_t +isl1208_sysfs_store_usr(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + int usr = -1; + + if (buf[0] == '0' && (buf[1] == 'x' || buf[1] == 'X')) { + if (sscanf(buf, "%x", &usr) != 1) + return -EINVAL; + } else { + if (sscanf(buf, "%d", &usr) != 1) + return -EINVAL; + } + + if (usr < 0 || usr > 0xffff) + return -EINVAL; + + if (isl1208_i2c_set_usr(to_i2c_client(dev->parent), usr)) + return -EIO; + + return count; +} + +static DEVICE_ATTR(usr, S_IRUGO | S_IWUSR, isl1208_sysfs_show_usr, + isl1208_sysfs_store_usr); + +static struct attribute *isl1208_rtc_attrs[] = { + &dev_attr_atrim.attr, + &dev_attr_dtrim.attr, + &dev_attr_usr.attr, + NULL +}; + +static const struct attribute_group isl1208_rtc_sysfs_files = { + .attrs = isl1208_rtc_attrs, +}; + +static struct attribute *isl1219_rtc_attrs[] = { + &dev_attr_timestamp0.attr, + NULL +}; + +static const struct attribute_group isl1219_rtc_sysfs_files = { + .attrs = isl1219_rtc_attrs, +}; + +static int isl1208_nvmem_read(void *priv, unsigned int off, void *buf, + size_t count) +{ + struct isl1208_state *isl1208 = priv; + struct i2c_client *client = to_i2c_client(isl1208->rtc->dev.parent); + int ret; + + /* nvmem sanitizes offset/count for us, but count==0 is possible */ + if (!count) + return count; + ret = isl1208_i2c_read_regs(client, ISL1208_REG_USR1 + off, buf, + count); + return ret == 0 ? count : ret; +} + +static int isl1208_nvmem_write(void *priv, unsigned int off, void *buf, + size_t count) +{ + struct isl1208_state *isl1208 = priv; + struct i2c_client *client = to_i2c_client(isl1208->rtc->dev.parent); + int ret; + + /* nvmem sanitizes off/count for us, but count==0 is possible */ + if (!count) + return count; + ret = isl1208_i2c_set_regs(client, ISL1208_REG_USR1 + off, buf, + count); + + return ret == 0 ? count : ret; +} + +static const struct nvmem_config isl1208_nvmem_config = { + .name = "isl1208_nvram", + .word_size = 1, + .stride = 1, + /* .size from chip specific config */ + .reg_read = isl1208_nvmem_read, + .reg_write = isl1208_nvmem_write, +}; + +static int isl1208_setup_irq(struct i2c_client *client, int irq) +{ + int rc = devm_request_threaded_irq(&client->dev, irq, NULL, + isl1208_rtc_interrupt, + IRQF_SHARED | IRQF_ONESHOT, + isl1208_driver.driver.name, + client); + if (!rc) { + device_init_wakeup(&client->dev, 1); + enable_irq_wake(irq); + } else { + dev_err(&client->dev, + "Unable to request irq %d, no alarm support\n", + irq); + } + return rc; +} + +static int +isl1208_probe(struct i2c_client *client, const struct i2c_device_id *id) +{ + int rc = 0; + struct isl1208_state *isl1208; + int evdet_irq = -1; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) + return -ENODEV; + + if (isl1208_i2c_validate_client(client) < 0) + return -ENODEV; + + /* Allocate driver state, point i2c client data to it */ + isl1208 = devm_kzalloc(&client->dev, sizeof(*isl1208), GFP_KERNEL); + if (!isl1208) + return -ENOMEM; + i2c_set_clientdata(client, isl1208); + + /* Determine which chip we have */ + if (client->dev.of_node) { + isl1208->config = of_device_get_match_data(&client->dev); + if (!isl1208->config) + return -ENODEV; + } else { + if (id->driver_data >= ISL_LAST_ID) + return -ENODEV; + isl1208->config = &isl1208_configs[id->driver_data]; + } + + isl1208->rtc = devm_rtc_allocate_device(&client->dev); + if (IS_ERR(isl1208->rtc)) + return PTR_ERR(isl1208->rtc); + + isl1208->rtc->ops = &isl1208_rtc_ops; + + /* Setup nvmem configuration in driver state struct */ + isl1208->nvmem_config = isl1208_nvmem_config; + isl1208->nvmem_config.size = isl1208->config->nvmem_length; + isl1208->nvmem_config.priv = isl1208; + + rc = isl1208_i2c_get_sr(client); + if (rc < 0) { + dev_err(&client->dev, "reading status failed\n"); + return rc; + } + + if (rc & ISL1208_REG_SR_RTCF) + dev_warn(&client->dev, "rtc power failure detected, " + "please set clock.\n"); + + if (isl1208->config->has_tamper) { + struct device_node *np = client->dev.of_node; + u32 evienb; + + rc = i2c_smbus_read_byte_data(client, ISL1219_REG_EV); + if (rc < 0) { + dev_err(&client->dev, "failed to read EV reg\n"); + return rc; + } + rc |= ISL1219_REG_EV_EVEN; + if (!of_property_read_u32(np, "isil,ev-evienb", &evienb)) { + if (evienb) + rc |= ISL1219_REG_EV_EVIENB; + else + rc &= ~ISL1219_REG_EV_EVIENB; + } + rc = i2c_smbus_write_byte_data(client, ISL1219_REG_EV, rc); + if (rc < 0) { + dev_err(&client->dev, "could not enable tamper detection\n"); + return rc; + } + evdet_irq = of_irq_get_byname(np, "evdet"); + } + if (isl1208->config->has_timestamp) { + rc = rtc_add_group(isl1208->rtc, &isl1219_rtc_sysfs_files); + if (rc) + return rc; + } + + rc = rtc_add_group(isl1208->rtc, &isl1208_rtc_sysfs_files); + if (rc) + return rc; + + if (client->irq > 0) { + rc = isl1208_setup_irq(client, client->irq); + if (rc) + return rc; + + } else { + clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, isl1208->rtc->features); + } + + if (evdet_irq > 0 && evdet_irq != client->irq) + rc = isl1208_setup_irq(client, evdet_irq); + if (rc) + return rc; + + rc = devm_rtc_nvmem_register(isl1208->rtc, &isl1208->nvmem_config); + if (rc) + return rc; + + return devm_rtc_register_device(isl1208->rtc); +} + +static struct i2c_driver isl1208_driver = { + .driver = { + .name = "rtc-isl1208", + .of_match_table = of_match_ptr(isl1208_of_match), + }, + .probe = isl1208_probe, + .id_table = isl1208_id, +}; + +module_i2c_driver(isl1208_driver); + +MODULE_AUTHOR("Herbert Valerio Riedel <hvr@gnu.org>"); +MODULE_DESCRIPTION("Intersil ISL1208 RTC driver"); +MODULE_LICENSE("GPL"); |