linux/drivers/rtc/rtc-davinci.c
Thomas Gleixner 1a59d1b8e0 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
Based on 1 normalized pattern(s):

  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 this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:35 -07:00

549 lines
14 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* DaVinci Power Management and Real Time Clock Driver for TI platforms
*
* Copyright (C) 2009 Texas Instruments, Inc
*
* Author: Miguel Aguilar <miguel.aguilar@ridgerun.com>
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/delay.h>
#include <linux/spinlock.h>
#include <linux/rtc.h>
#include <linux/bcd.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/slab.h>
/*
* The DaVinci RTC is a simple RTC with the following
* Sec: 0 - 59 : BCD count
* Min: 0 - 59 : BCD count
* Hour: 0 - 23 : BCD count
* Day: 0 - 0x7FFF(32767) : Binary count ( Over 89 years )
*/
/* PRTC interface registers */
#define DAVINCI_PRTCIF_PID 0x00
#define PRTCIF_CTLR 0x04
#define PRTCIF_LDATA 0x08
#define PRTCIF_UDATA 0x0C
#define PRTCIF_INTEN 0x10
#define PRTCIF_INTFLG 0x14
/* PRTCIF_CTLR bit fields */
#define PRTCIF_CTLR_BUSY BIT(31)
#define PRTCIF_CTLR_SIZE BIT(25)
#define PRTCIF_CTLR_DIR BIT(24)
#define PRTCIF_CTLR_BENU_MSB BIT(23)
#define PRTCIF_CTLR_BENU_3RD_BYTE BIT(22)
#define PRTCIF_CTLR_BENU_2ND_BYTE BIT(21)
#define PRTCIF_CTLR_BENU_LSB BIT(20)
#define PRTCIF_CTLR_BENU_MASK (0x00F00000)
#define PRTCIF_CTLR_BENL_MSB BIT(19)
#define PRTCIF_CTLR_BENL_3RD_BYTE BIT(18)
#define PRTCIF_CTLR_BENL_2ND_BYTE BIT(17)
#define PRTCIF_CTLR_BENL_LSB BIT(16)
#define PRTCIF_CTLR_BENL_MASK (0x000F0000)
/* PRTCIF_INTEN bit fields */
#define PRTCIF_INTEN_RTCSS BIT(1)
#define PRTCIF_INTEN_RTCIF BIT(0)
#define PRTCIF_INTEN_MASK (PRTCIF_INTEN_RTCSS \
| PRTCIF_INTEN_RTCIF)
/* PRTCIF_INTFLG bit fields */
#define PRTCIF_INTFLG_RTCSS BIT(1)
#define PRTCIF_INTFLG_RTCIF BIT(0)
#define PRTCIF_INTFLG_MASK (PRTCIF_INTFLG_RTCSS \
| PRTCIF_INTFLG_RTCIF)
/* PRTC subsystem registers */
#define PRTCSS_RTC_INTC_EXTENA1 (0x0C)
#define PRTCSS_RTC_CTRL (0x10)
#define PRTCSS_RTC_WDT (0x11)
#define PRTCSS_RTC_TMR0 (0x12)
#define PRTCSS_RTC_TMR1 (0x13)
#define PRTCSS_RTC_CCTRL (0x14)
#define PRTCSS_RTC_SEC (0x15)
#define PRTCSS_RTC_MIN (0x16)
#define PRTCSS_RTC_HOUR (0x17)
#define PRTCSS_RTC_DAY0 (0x18)
#define PRTCSS_RTC_DAY1 (0x19)
#define PRTCSS_RTC_AMIN (0x1A)
#define PRTCSS_RTC_AHOUR (0x1B)
#define PRTCSS_RTC_ADAY0 (0x1C)
#define PRTCSS_RTC_ADAY1 (0x1D)
#define PRTCSS_RTC_CLKC_CNT (0x20)
/* PRTCSS_RTC_INTC_EXTENA1 */
#define PRTCSS_RTC_INTC_EXTENA1_MASK (0x07)
/* PRTCSS_RTC_CTRL bit fields */
#define PRTCSS_RTC_CTRL_WDTBUS BIT(7)
#define PRTCSS_RTC_CTRL_WEN BIT(6)
#define PRTCSS_RTC_CTRL_WDRT BIT(5)
#define PRTCSS_RTC_CTRL_WDTFLG BIT(4)
#define PRTCSS_RTC_CTRL_TE BIT(3)
#define PRTCSS_RTC_CTRL_TIEN BIT(2)
#define PRTCSS_RTC_CTRL_TMRFLG BIT(1)
#define PRTCSS_RTC_CTRL_TMMD BIT(0)
/* PRTCSS_RTC_CCTRL bit fields */
#define PRTCSS_RTC_CCTRL_CALBUSY BIT(7)
#define PRTCSS_RTC_CCTRL_DAEN BIT(5)
#define PRTCSS_RTC_CCTRL_HAEN BIT(4)
#define PRTCSS_RTC_CCTRL_MAEN BIT(3)
#define PRTCSS_RTC_CCTRL_ALMFLG BIT(2)
#define PRTCSS_RTC_CCTRL_AIEN BIT(1)
#define PRTCSS_RTC_CCTRL_CAEN BIT(0)
static DEFINE_SPINLOCK(davinci_rtc_lock);
struct davinci_rtc {
struct rtc_device *rtc;
void __iomem *base;
int irq;
};
static inline void rtcif_write(struct davinci_rtc *davinci_rtc,
u32 val, u32 addr)
{
writel(val, davinci_rtc->base + addr);
}
static inline u32 rtcif_read(struct davinci_rtc *davinci_rtc, u32 addr)
{
return readl(davinci_rtc->base + addr);
}
static inline void rtcif_wait(struct davinci_rtc *davinci_rtc)
{
while (rtcif_read(davinci_rtc, PRTCIF_CTLR) & PRTCIF_CTLR_BUSY)
cpu_relax();
}
static inline void rtcss_write(struct davinci_rtc *davinci_rtc,
unsigned long val, u8 addr)
{
rtcif_wait(davinci_rtc);
rtcif_write(davinci_rtc, PRTCIF_CTLR_BENL_LSB | addr, PRTCIF_CTLR);
rtcif_write(davinci_rtc, val, PRTCIF_LDATA);
rtcif_wait(davinci_rtc);
}
static inline u8 rtcss_read(struct davinci_rtc *davinci_rtc, u8 addr)
{
rtcif_wait(davinci_rtc);
rtcif_write(davinci_rtc, PRTCIF_CTLR_DIR | PRTCIF_CTLR_BENL_LSB | addr,
PRTCIF_CTLR);
rtcif_wait(davinci_rtc);
return rtcif_read(davinci_rtc, PRTCIF_LDATA);
}
static inline void davinci_rtcss_calendar_wait(struct davinci_rtc *davinci_rtc)
{
while (rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL) &
PRTCSS_RTC_CCTRL_CALBUSY)
cpu_relax();
}
static irqreturn_t davinci_rtc_interrupt(int irq, void *class_dev)
{
struct davinci_rtc *davinci_rtc = class_dev;
unsigned long events = 0;
u32 irq_flg;
u8 alm_irq, tmr_irq;
u8 rtc_ctrl, rtc_cctrl;
int ret = IRQ_NONE;
irq_flg = rtcif_read(davinci_rtc, PRTCIF_INTFLG) &
PRTCIF_INTFLG_RTCSS;
alm_irq = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL) &
PRTCSS_RTC_CCTRL_ALMFLG;
tmr_irq = rtcss_read(davinci_rtc, PRTCSS_RTC_CTRL) &
PRTCSS_RTC_CTRL_TMRFLG;
if (irq_flg) {
if (alm_irq) {
events |= RTC_IRQF | RTC_AF;
rtc_cctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL);
rtc_cctrl |= PRTCSS_RTC_CCTRL_ALMFLG;
rtcss_write(davinci_rtc, rtc_cctrl, PRTCSS_RTC_CCTRL);
} else if (tmr_irq) {
events |= RTC_IRQF | RTC_PF;
rtc_ctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CTRL);
rtc_ctrl |= PRTCSS_RTC_CTRL_TMRFLG;
rtcss_write(davinci_rtc, rtc_ctrl, PRTCSS_RTC_CTRL);
}
rtcif_write(davinci_rtc, PRTCIF_INTFLG_RTCSS,
PRTCIF_INTFLG);
rtc_update_irq(davinci_rtc->rtc, 1, events);
ret = IRQ_HANDLED;
}
return ret;
}
static int
davinci_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
{
struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
u8 rtc_ctrl;
unsigned long flags;
int ret = 0;
spin_lock_irqsave(&davinci_rtc_lock, flags);
rtc_ctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CTRL);
switch (cmd) {
case RTC_WIE_ON:
rtc_ctrl |= PRTCSS_RTC_CTRL_WEN | PRTCSS_RTC_CTRL_WDTFLG;
break;
case RTC_WIE_OFF:
rtc_ctrl &= ~PRTCSS_RTC_CTRL_WEN;
break;
default:
ret = -ENOIOCTLCMD;
}
rtcss_write(davinci_rtc, rtc_ctrl, PRTCSS_RTC_CTRL);
spin_unlock_irqrestore(&davinci_rtc_lock, flags);
return ret;
}
static int convertfromdays(u16 days, struct rtc_time *tm)
{
int tmp_days, year, mon;
for (year = 2000;; year++) {
tmp_days = rtc_year_days(1, 12, year);
if (days >= tmp_days)
days -= tmp_days;
else {
for (mon = 0;; mon++) {
tmp_days = rtc_month_days(mon, year);
if (days >= tmp_days) {
days -= tmp_days;
} else {
tm->tm_year = year - 1900;
tm->tm_mon = mon;
tm->tm_mday = days + 1;
break;
}
}
break;
}
}
return 0;
}
static int convert2days(u16 *days, struct rtc_time *tm)
{
int i;
*days = 0;
/* epoch == 1900 */
if (tm->tm_year < 100 || tm->tm_year > 199)
return -EINVAL;
for (i = 2000; i < 1900 + tm->tm_year; i++)
*days += rtc_year_days(1, 12, i);
*days += rtc_year_days(tm->tm_mday, tm->tm_mon, 1900 + tm->tm_year);
return 0;
}
static int davinci_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
u16 days = 0;
u8 day0, day1;
unsigned long flags;
spin_lock_irqsave(&davinci_rtc_lock, flags);
davinci_rtcss_calendar_wait(davinci_rtc);
tm->tm_sec = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_SEC));
davinci_rtcss_calendar_wait(davinci_rtc);
tm->tm_min = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_MIN));
davinci_rtcss_calendar_wait(davinci_rtc);
tm->tm_hour = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_HOUR));
davinci_rtcss_calendar_wait(davinci_rtc);
day0 = rtcss_read(davinci_rtc, PRTCSS_RTC_DAY0);
davinci_rtcss_calendar_wait(davinci_rtc);
day1 = rtcss_read(davinci_rtc, PRTCSS_RTC_DAY1);
spin_unlock_irqrestore(&davinci_rtc_lock, flags);
days |= day1;
days <<= 8;
days |= day0;
if (convertfromdays(days, tm) < 0)
return -EINVAL;
return 0;
}
static int davinci_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
u16 days;
u8 rtc_cctrl;
unsigned long flags;
if (convert2days(&days, tm) < 0)
return -EINVAL;
spin_lock_irqsave(&davinci_rtc_lock, flags);
davinci_rtcss_calendar_wait(davinci_rtc);
rtcss_write(davinci_rtc, bin2bcd(tm->tm_sec), PRTCSS_RTC_SEC);
davinci_rtcss_calendar_wait(davinci_rtc);
rtcss_write(davinci_rtc, bin2bcd(tm->tm_min), PRTCSS_RTC_MIN);
davinci_rtcss_calendar_wait(davinci_rtc);
rtcss_write(davinci_rtc, bin2bcd(tm->tm_hour), PRTCSS_RTC_HOUR);
davinci_rtcss_calendar_wait(davinci_rtc);
rtcss_write(davinci_rtc, days & 0xFF, PRTCSS_RTC_DAY0);
davinci_rtcss_calendar_wait(davinci_rtc);
rtcss_write(davinci_rtc, (days & 0xFF00) >> 8, PRTCSS_RTC_DAY1);
rtc_cctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL);
rtc_cctrl |= PRTCSS_RTC_CCTRL_CAEN;
rtcss_write(davinci_rtc, rtc_cctrl, PRTCSS_RTC_CCTRL);
spin_unlock_irqrestore(&davinci_rtc_lock, flags);
return 0;
}
static int davinci_rtc_alarm_irq_enable(struct device *dev,
unsigned int enabled)
{
struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
unsigned long flags;
u8 rtc_cctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL);
spin_lock_irqsave(&davinci_rtc_lock, flags);
if (enabled)
rtc_cctrl |= PRTCSS_RTC_CCTRL_DAEN |
PRTCSS_RTC_CCTRL_HAEN |
PRTCSS_RTC_CCTRL_MAEN |
PRTCSS_RTC_CCTRL_ALMFLG |
PRTCSS_RTC_CCTRL_AIEN;
else
rtc_cctrl &= ~PRTCSS_RTC_CCTRL_AIEN;
davinci_rtcss_calendar_wait(davinci_rtc);
rtcss_write(davinci_rtc, rtc_cctrl, PRTCSS_RTC_CCTRL);
spin_unlock_irqrestore(&davinci_rtc_lock, flags);
return 0;
}
static int davinci_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
{
struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
u16 days = 0;
u8 day0, day1;
unsigned long flags;
alm->time.tm_sec = 0;
spin_lock_irqsave(&davinci_rtc_lock, flags);
davinci_rtcss_calendar_wait(davinci_rtc);
alm->time.tm_min = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_AMIN));
davinci_rtcss_calendar_wait(davinci_rtc);
alm->time.tm_hour = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_AHOUR));
davinci_rtcss_calendar_wait(davinci_rtc);
day0 = rtcss_read(davinci_rtc, PRTCSS_RTC_ADAY0);
davinci_rtcss_calendar_wait(davinci_rtc);
day1 = rtcss_read(davinci_rtc, PRTCSS_RTC_ADAY1);
spin_unlock_irqrestore(&davinci_rtc_lock, flags);
days |= day1;
days <<= 8;
days |= day0;
if (convertfromdays(days, &alm->time) < 0)
return -EINVAL;
alm->pending = !!(rtcss_read(davinci_rtc,
PRTCSS_RTC_CCTRL) &
PRTCSS_RTC_CCTRL_AIEN);
alm->enabled = alm->pending && device_may_wakeup(dev);
return 0;
}
static int davinci_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
{
struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
unsigned long flags;
u16 days;
if (alm->time.tm_mday <= 0 && alm->time.tm_mon < 0
&& alm->time.tm_year < 0) {
struct rtc_time tm;
unsigned long now, then;
davinci_rtc_read_time(dev, &tm);
rtc_tm_to_time(&tm, &now);
alm->time.tm_mday = tm.tm_mday;
alm->time.tm_mon = tm.tm_mon;
alm->time.tm_year = tm.tm_year;
rtc_tm_to_time(&alm->time, &then);
if (then < now) {
rtc_time_to_tm(now + 24 * 60 * 60, &tm);
alm->time.tm_mday = tm.tm_mday;
alm->time.tm_mon = tm.tm_mon;
alm->time.tm_year = tm.tm_year;
}
}
if (convert2days(&days, &alm->time) < 0)
return -EINVAL;
spin_lock_irqsave(&davinci_rtc_lock, flags);
davinci_rtcss_calendar_wait(davinci_rtc);
rtcss_write(davinci_rtc, bin2bcd(alm->time.tm_min), PRTCSS_RTC_AMIN);
davinci_rtcss_calendar_wait(davinci_rtc);
rtcss_write(davinci_rtc, bin2bcd(alm->time.tm_hour), PRTCSS_RTC_AHOUR);
davinci_rtcss_calendar_wait(davinci_rtc);
rtcss_write(davinci_rtc, days & 0xFF, PRTCSS_RTC_ADAY0);
davinci_rtcss_calendar_wait(davinci_rtc);
rtcss_write(davinci_rtc, (days & 0xFF00) >> 8, PRTCSS_RTC_ADAY1);
spin_unlock_irqrestore(&davinci_rtc_lock, flags);
return 0;
}
static const struct rtc_class_ops davinci_rtc_ops = {
.ioctl = davinci_rtc_ioctl,
.read_time = davinci_rtc_read_time,
.set_time = davinci_rtc_set_time,
.alarm_irq_enable = davinci_rtc_alarm_irq_enable,
.read_alarm = davinci_rtc_read_alarm,
.set_alarm = davinci_rtc_set_alarm,
};
static int __init davinci_rtc_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct davinci_rtc *davinci_rtc;
struct resource *res;
int ret = 0;
davinci_rtc = devm_kzalloc(&pdev->dev, sizeof(struct davinci_rtc), GFP_KERNEL);
if (!davinci_rtc)
return -ENOMEM;
davinci_rtc->irq = platform_get_irq(pdev, 0);
if (davinci_rtc->irq < 0) {
dev_err(dev, "no RTC irq\n");
return davinci_rtc->irq;
}
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
davinci_rtc->base = devm_ioremap_resource(dev, res);
if (IS_ERR(davinci_rtc->base))
return PTR_ERR(davinci_rtc->base);
platform_set_drvdata(pdev, davinci_rtc);
davinci_rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
&davinci_rtc_ops, THIS_MODULE);
if (IS_ERR(davinci_rtc->rtc)) {
dev_err(dev, "unable to register RTC device, err %d\n",
ret);
return PTR_ERR(davinci_rtc->rtc);
}
rtcif_write(davinci_rtc, PRTCIF_INTFLG_RTCSS, PRTCIF_INTFLG);
rtcif_write(davinci_rtc, 0, PRTCIF_INTEN);
rtcss_write(davinci_rtc, 0, PRTCSS_RTC_INTC_EXTENA1);
rtcss_write(davinci_rtc, 0, PRTCSS_RTC_CTRL);
rtcss_write(davinci_rtc, 0, PRTCSS_RTC_CCTRL);
ret = devm_request_irq(dev, davinci_rtc->irq, davinci_rtc_interrupt,
0, "davinci_rtc", davinci_rtc);
if (ret < 0) {
dev_err(dev, "unable to register davinci RTC interrupt\n");
return ret;
}
/* Enable interrupts */
rtcif_write(davinci_rtc, PRTCIF_INTEN_RTCSS, PRTCIF_INTEN);
rtcss_write(davinci_rtc, PRTCSS_RTC_INTC_EXTENA1_MASK,
PRTCSS_RTC_INTC_EXTENA1);
rtcss_write(davinci_rtc, PRTCSS_RTC_CCTRL_CAEN, PRTCSS_RTC_CCTRL);
device_init_wakeup(&pdev->dev, 0);
return 0;
}
static int __exit davinci_rtc_remove(struct platform_device *pdev)
{
struct davinci_rtc *davinci_rtc = platform_get_drvdata(pdev);
device_init_wakeup(&pdev->dev, 0);
rtcif_write(davinci_rtc, 0, PRTCIF_INTEN);
return 0;
}
static struct platform_driver davinci_rtc_driver = {
.remove = __exit_p(davinci_rtc_remove),
.driver = {
.name = "rtc_davinci",
},
};
module_platform_driver_probe(davinci_rtc_driver, davinci_rtc_probe);
MODULE_AUTHOR("Miguel Aguilar <miguel.aguilar@ridgerun.com>");
MODULE_DESCRIPTION("Texas Instruments DaVinci PRTC Driver");
MODULE_LICENSE("GPL");