|  | /* | 
|  | * Intersil ISL1208 rtc class driver | 
|  | * | 
|  | * Copyright 2005,2006 Hebert Valerio Riedel <hvr@gnu.org> | 
|  | * | 
|  | *  This program is free software; you can redistribute  it and/or modify it | 
|  | *  under  the terms of  the GNU General  Public License as published by the | 
|  | *  Free Software Foundation;  either version 2 of the  License, or (at your | 
|  | *  option) any later version. | 
|  | * | 
|  | */ | 
|  |  | 
|  | #include <linux/module.h> | 
|  | #include <linux/i2c.h> | 
|  | #include <linux/bcd.h> | 
|  | #include <linux/rtc.h> | 
|  |  | 
|  | #define DRV_VERSION "0.3" | 
|  |  | 
|  | /* 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_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 ISL1208_REG_09  0x09	/* reserved */ | 
|  | #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 | 
|  |  | 
|  | static struct i2c_driver isl1208_driver; | 
|  |  | 
|  | /* block read */ | 
|  | static int | 
|  | isl1208_i2c_read_regs(struct i2c_client *client, u8 reg, u8 buf[], | 
|  | unsigned len) | 
|  | { | 
|  | u8 reg_addr[1] = { reg }; | 
|  | struct i2c_msg msgs[2] = { | 
|  | {client->addr, 0, sizeof(reg_addr), reg_addr} | 
|  | , | 
|  | {client->addr, I2C_M_RD, len, buf} | 
|  | }; | 
|  | int ret; | 
|  |  | 
|  | BUG_ON(reg > ISL1208_REG_USR2); | 
|  | BUG_ON(reg + len > ISL1208_REG_USR2 + 1); | 
|  |  | 
|  | ret = i2c_transfer(client->adapter, msgs, 2); | 
|  | if (ret > 0) | 
|  | ret = 0; | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | /* block write */ | 
|  | static int | 
|  | isl1208_i2c_set_regs(struct i2c_client *client, u8 reg, u8 const buf[], | 
|  | unsigned len) | 
|  | { | 
|  | u8 i2c_buf[ISL1208_REG_USR2 + 2]; | 
|  | struct i2c_msg msgs[1] = { | 
|  | {client->addr, 0, len + 1, i2c_buf} | 
|  | }; | 
|  | int ret; | 
|  |  | 
|  | BUG_ON(reg > ISL1208_REG_USR2); | 
|  | BUG_ON(reg + len > ISL1208_REG_USR2 + 1); | 
|  |  | 
|  | i2c_buf[0] = reg; | 
|  | memcpy(&i2c_buf[1], &buf[0], len); | 
|  |  | 
|  | ret = i2c_transfer(client->adapter, msgs, 1); | 
|  | if (ret > 0) | 
|  | ret = 0; | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | /* simple check to see wether 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) | 
|  | { | 
|  | int sr = i2c_smbus_read_byte_data(client, ISL1208_REG_SR); | 
|  | if (sr < 0) | 
|  | return -EIO; | 
|  |  | 
|  | return 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; | 
|  | } | 
|  |  | 
|  | 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; | 
|  | } | 
|  |  | 
|  | 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 - 1) | 
|  | seq_printf(seq, "digital_trim\t: %d ppm\n", dtr); | 
|  |  | 
|  | 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; | 
|  | unsigned long rtc_secs, alarm_secs; | 
|  | struct rtc_time rtc_tm; | 
|  | int err, enable; | 
|  |  | 
|  | err = isl1208_i2c_read_time(client, &rtc_tm); | 
|  | if (err) | 
|  | return err; | 
|  | err = rtc_tm_to_time(&rtc_tm, &rtc_secs); | 
|  | if (err) | 
|  | return err; | 
|  | err = rtc_tm_to_time(alarm_tm, &alarm_secs); | 
|  | if (err) | 
|  | return err; | 
|  |  | 
|  | /* If the alarm time is before the current time disable the alarm */ | 
|  | if (!alarm->enabled || alarm_secs <= rtc_secs) | 
|  | 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 = 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 irqreturn_t | 
|  | isl1208_rtc_interrupt(int irq, void *data) | 
|  | { | 
|  | unsigned long timeout = jiffies + msecs_to_jiffies(1000); | 
|  | struct i2c_client *client = data; | 
|  | 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"); | 
|  |  | 
|  | /* 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; | 
|  | } | 
|  |  | 
|  | 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)); | 
|  | 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)); | 
|  | if (dtr < 0) | 
|  | return dtr; | 
|  |  | 
|  | return sprintf(buf, "%d ppm\n", dtr); | 
|  | } | 
|  |  | 
|  | 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)); | 
|  | 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; | 
|  |  | 
|  | return isl1208_i2c_set_usr(to_i2c_client(dev), usr) ? -EIO : 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 int | 
|  | isl1208_probe(struct i2c_client *client, const struct i2c_device_id *id) | 
|  | { | 
|  | int rc = 0; | 
|  | struct rtc_device *rtc; | 
|  |  | 
|  | if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) | 
|  | return -ENODEV; | 
|  |  | 
|  | if (isl1208_i2c_validate_client(client) < 0) | 
|  | return -ENODEV; | 
|  |  | 
|  | dev_info(&client->dev, | 
|  | "chip found, driver version " DRV_VERSION "\n"); | 
|  |  | 
|  | if (client->irq > 0) { | 
|  | rc = request_threaded_irq(client->irq, NULL, | 
|  | isl1208_rtc_interrupt, | 
|  | IRQF_SHARED, | 
|  | isl1208_driver.driver.name, client); | 
|  | if (!rc) { | 
|  | device_init_wakeup(&client->dev, 1); | 
|  | enable_irq_wake(client->irq); | 
|  | } else { | 
|  | dev_err(&client->dev, | 
|  | "Unable to request irq %d, no alarm support\n", | 
|  | client->irq); | 
|  | client->irq = 0; | 
|  | } | 
|  | } | 
|  |  | 
|  | rtc = rtc_device_register(isl1208_driver.driver.name, | 
|  | &client->dev, &isl1208_rtc_ops, | 
|  | THIS_MODULE); | 
|  | if (IS_ERR(rtc)) { | 
|  | rc = PTR_ERR(rtc); | 
|  | goto exit_free_irq; | 
|  | } | 
|  |  | 
|  | i2c_set_clientdata(client, rtc); | 
|  |  | 
|  | rc = isl1208_i2c_get_sr(client); | 
|  | if (rc < 0) { | 
|  | dev_err(&client->dev, "reading status failed\n"); | 
|  | goto exit_unregister; | 
|  | } | 
|  |  | 
|  | if (rc & ISL1208_REG_SR_RTCF) | 
|  | dev_warn(&client->dev, "rtc power failure detected, " | 
|  | "please set clock.\n"); | 
|  |  | 
|  | rc = sysfs_create_group(&client->dev.kobj, &isl1208_rtc_sysfs_files); | 
|  | if (rc) | 
|  | goto exit_unregister; | 
|  |  | 
|  | return 0; | 
|  |  | 
|  | exit_unregister: | 
|  | rtc_device_unregister(rtc); | 
|  | exit_free_irq: | 
|  | if (client->irq) | 
|  | free_irq(client->irq, client); | 
|  |  | 
|  | return rc; | 
|  | } | 
|  |  | 
|  | static int | 
|  | isl1208_remove(struct i2c_client *client) | 
|  | { | 
|  | struct rtc_device *rtc = i2c_get_clientdata(client); | 
|  |  | 
|  | sysfs_remove_group(&client->dev.kobj, &isl1208_rtc_sysfs_files); | 
|  | rtc_device_unregister(rtc); | 
|  | if (client->irq) | 
|  | free_irq(client->irq, client); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static const struct i2c_device_id isl1208_id[] = { | 
|  | { "isl1208", 0 }, | 
|  | { } | 
|  | }; | 
|  | MODULE_DEVICE_TABLE(i2c, isl1208_id); | 
|  |  | 
|  | static struct i2c_driver isl1208_driver = { | 
|  | .driver = { | 
|  | .name = "rtc-isl1208", | 
|  | }, | 
|  | .probe = isl1208_probe, | 
|  | .remove = isl1208_remove, | 
|  | .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"); | 
|  | MODULE_VERSION(DRV_VERSION); |