/*
* rtc-twl4030.c -- TWL4030 Real Time Clock interface
*
* Copyright (C) 2007 MontaVista Software, Inc
* Author: Alexandre Rusev <source@mvista.com>
*
* Based on original TI driver twl4030-rtc.c
* Copyright (C) 2006 Texas Instruments, Inc.
*
* Based on rtc-omap.c
* Copyright (C) 2003 MontaVista Software, Inc.
* Author: George G. Davis <gdavis@mvista.com> or <source@mvista.com>
* Copyright (C) 2006 David Brownell
*
* 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/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/rtc.h>
#include <linux/bcd.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/i2c/twl4030.h>
/*
* RTC block register offsets (use TWL_MODULE_RTC)
*/
#define REG_SECONDS_REG 0x00
#define REG_MINUTES_REG 0x01
#define REG_HOURS_REG 0x02
#define REG_DAYS_REG 0x03
#define REG_MONTHS_REG 0x04
#define REG_YEARS_REG 0x05
#define REG_WEEKS_REG 0x06
#define REG_ALARM_SECONDS_REG 0x07
#define REG_ALARM_MINUTES_REG 0x08
#define REG_ALARM_HOURS_REG 0x09
#define REG_ALARM_DAYS_REG 0x0A
#define REG_ALARM_MONTHS_REG 0x0B
#define REG_ALARM_YEARS_REG 0x0C
#define REG_RTC_CTRL_REG 0x0D
#define REG_RTC_STATUS_REG 0x0E
#define REG_RTC_INTERRUPTS_REG 0x0F
#define REG_RTC_COMP_LSB_REG 0x10
#define REG_RTC_COMP_MSB_REG 0x11
/* RTC_CTRL_REG bitfields */
#define BIT_RTC_CTRL_REG_STOP_RTC_M 0x01
#define BIT_RTC_CTRL_REG_ROUND_30S_M 0x02
#define BIT_RTC_CTRL_REG_AUTO_COMP_M 0x04
#define BIT_RTC_CTRL_REG_MODE_12_24_M 0x08
#define BIT_RTC_CTRL_REG_TEST_MODE_M 0x10
#define BIT_RTC_CTRL_REG_SET_32_COUNTER_M 0x20
#define BIT_RTC_CTRL_REG_GET_TIME_M 0x40
/* RTC_STATUS_REG bitfields */
#define BIT_RTC_STATUS_REG_RUN_M 0x02
#define BIT_RTC_STATUS_REG_1S_EVENT_M 0x04
#define BIT_RTC_STATUS_REG_1M_EVENT_M 0x08
#define BIT_RTC_STATUS_REG_1H_EVENT_M 0x10
#define BIT_RTC_STATUS_REG_1D_EVENT_M 0x20
#define BIT_RTC_STATUS_REG_ALARM_M 0x40
#define BIT_RTC_STATUS_REG_POWER_UP_M 0x80
/* RTC_INTERRUPTS_REG bitfields */
#define BIT_RTC_INTERRUPTS_REG_EVERY_M 0x03
#define BIT_RTC_INTERRUPTS_REG_IT_TIMER_M 0x04
#define BIT_RTC_INTERRUPTS_REG_IT_ALARM_M 0x08
/* REG_SECONDS_REG through REG_YEARS_REG is how many registers? */
#define ALL_TIME_REGS 6
/*----------------------------------------------------------------------*/
/*
* Supports 1 byte read from TWL4030 RTC register.
*/
static int twl4030_rtc_read_u8(u8 *data, u8 reg)
{
int ret;
ret = twl4030_i2c_read_u8(TWL4030_MODULE_RTC, data, reg);
if (ret < 0)
pr_err("twl4030_rtc: Could not read TWL4030"
"register %X - error %d\n", reg, ret);
return ret;
}
/*
* Supports 1 byte write to TWL4030 RTC registers.
*/
static int twl4030_rtc_write_u8(u8 data, u8 reg)
{
int ret;
ret = twl4030_i2c_write_u8(TWL4030_MODULE_RTC, data, reg);
if (ret < 0)
pr_err("twl4030_rtc: Could not write TWL4030"
"register %X - error %d\n", reg, ret);
return ret;
}
/*
* Cache the value for timer/alarm interrupts register; this is
* only changed by callers holding rtc ops lock (or resume).
*/
static unsigned char rtc_irq_bits;
/*
* Enable timer and/or alarm interrupts.
*/
static int set_rtc_irq_bit(unsigned char bit)
{
unsigned char val;
int ret;
val = rtc_irq_bits | bit;
ret = twl4030_rtc_write_u8(val, REG_RTC_INTERRUPTS_REG);
if (ret == 0)
rtc_irq_bits = val;
return ret;
}
/*
* Disable timer and/or alarm interrupts.
*/
static int mask_rtc_irq_bit(unsigned char bit)
{
unsigned char val;
int ret;
val = rtc_irq_bits & ~bit;
ret = twl4030_rtc_write_u8(val, REG_RTC_INTERRUPTS_REG);
if (ret == 0)
rtc_irq_bits = val;
return ret;
}
static inline int twl4030_rtc_alarm_irq_set_state(int enabled)
{
int ret;
if (enabled)
ret = set_rtc_irq_bit(BIT_RTC_INTERRUPTS_REG_IT_ALARM_M);
else
ret = mask_rtc_irq_bit(BIT_RTC_INTERRUPTS_REG_IT_ALARM_M);
return ret;
}
static inline int twl4030_rtc_irq_set_state(int enabled)
{
int ret;
if (enabled)
ret = set_rtc_irq_bit(BIT_RTC_INTERRUPTS_REG_IT_TIMER_M);
else
ret = mask_rtc_irq_bit(BIT_RTC_INTERRUPTS_REG_IT_TIMER_M);
return ret;
}
/*
* Gets current TWL4030 RTC time and date parameters.
*
* The RTC's time/alarm representation is not what gmtime(3) requires
* Linux to use:
*
* - Months are 1..12 vs Linux 0-11
* - Years are 0..99 vs Linux 1900..N (we assume 21st century)
*/
static int twl4030_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
unsigned char rtc_data[ALL_TIME_REGS + 1];
int ret;
u8 save_control;
ret = twl4030_rtc_read_u8(&save_control, REG_RTC_CTRL_REG);
if (ret < 0)
return ret;
save_control |= BIT_RTC_CTRL_REG_GET_TIME_M;
ret = twl4030_rtc_write_u8(save_control, REG_RTC_CTRL_REG);
if (ret < 0)
return ret;
ret = twl4030_i2c_read(TWL4030_MODULE_RTC, rtc_data,
REG_SECONDS_REG, ALL_TIME_REGS);
if (ret < 0) {
dev_err(dev, "rtc_read_time error %d\n", ret);
return ret;
}
tm->tm_sec = bcd2bin(rtc_data[0]);
tm->tm_min = bcd2bin(rtc_data[1]);
tm->tm_hour = bcd2bin(rtc_data[2]);
tm->tm_mday = bcd2bin(rtc_data[3]);
tm->tm_mon = bcd2bin(rtc_data[4]) - 1;
tm->tm_year = bcd2bin(rtc_data[5]) + 100;
return ret;
}
static int twl4030_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
unsigned char save_control;
unsigned char rtc_data[ALL_TIME_REGS + 1];
int ret;
rtc_data[1] = bin2bcd(tm->tm_sec);
rtc_data[2] = bin2bcd(tm->tm_min);
rtc_data[3] = bin2bcd(tm->tm_hour);
rtc_data[4] = bin2bcd(tm->tm_mday);
rtc_data[5] = bin2bcd(tm->tm_mon + 1);
rtc_data[6] = bin2bcd(tm->tm_year - 100);
/* Stop RTC while updating the TC registers */
ret = twl4030_rtc_read_u8(&save_control, REG_RTC_CTRL_REG);
if (ret < 0)
goto out;
save_control &= ~BIT_RTC_CTRL_REG_STOP_RTC_M;
twl4030_rtc_write_u8(save_control, REG_RTC_CTRL_REG);
if (ret < 0)
goto out;
/* update all the time registers in one shot */
ret = twl4030_i2c_write(TWL4030_MODULE_RTC, rtc_data,
REG_SECONDS_REG, ALL_TIME_REGS);
if (ret < 0) {
dev_err(dev, "rtc_set_time error %d\n", ret);
goto out;
}
/* Start back RTC */
save_control |= BIT_RTC_CTRL_REG_STOP_RTC_M;
ret = twl4030_rtc_write_u8(save_control, REG_RTC_CTRL_REG);
out:
return ret;
}
/*
* Gets current TWL4030 RTC alarm time.
*/
static int twl4030_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
{
unsigned char rtc_data[ALL_TIME_REGS + 1];
int ret;
ret = twl4030_i2c_read(TWL4030_MODULE_RTC, rtc_data,
REG_ALARM_SECONDS_REG, ALL_TIME_REGS);
if (ret < 0) {
dev_err(dev, "rtc_read_alarm error %d\n", ret);
return ret;
}
/* some of these fields may be wildcard/"match all" */
alm->time.tm_sec = bcd2bin(rtc_data[0]);
alm->time.tm_min = bcd2bin(rtc_data[1]);
alm->time.tm_hour = bcd2bin(rtc_data[2]);
alm->time.tm_mday = bcd2bin(rtc_data[3]);
alm->time.tm_mon = bcd2bin(rtc_data[4]) - 1;
alm->time.tm_year = bcd2bin(rtc_data[5]) + 100;
/* report cached alarm enable state */
if (rtc_irq_bits & BIT_RTC_INTERRUPTS_REG_IT_ALARM_M)
alm->enabled = 1;
return ret;
}
static int twl4030_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
{
unsigned char alarm_data[ALL_TIME_REGS + 1];
int ret;
ret = twl4030_rtc_ala
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