638 lines
17 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2023 Rockchip Electronics Co., Ltd
*/
#include <linux/bcd.h>
#include <linux/kernel.h>
#include <linux/mfd/rk630.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/rtc.h>
/* RTC_CTRL_REG bitfields */
#define RTC_CTRL_REG_START_RTC BIT(0)
/* RK630 has a shadowed register for saving a "frozen" RTC time.
* When user setting "GET_TIME" to 1, the time will save in this shadowed
* register. If set "READSEL" to 1, user read rtc time register, actually
* get the time of that moment. If we need the real time, clr this bit.
*/
#define RTC_CTRL_REG_RTC_GET_TIME BIT(6)
#define RTC_CTRL_REG_RTC_READSEL_M BIT(7)
#define RTC_INT_REG_ALARM_EN BIT(7)
#define RTC_STATUS_MASK 0xFF
#define SECONDS_REG_MSK 0x7F
#define MINUTES_REG_MAK 0x7F
#define HOURS_REG_MSK 0x3F
#define DAYS_REG_MSK 0x3F
#define MONTHS_REG_MSK 0x1F
#define YEARS_REG_MSK 0xFF
#define WEEKS_REG_MSK 0x7
#define RTC_VREF_INIT 0x40
#define RTC_XO_START_MIR 0x40
#define NUM_TIME_REGS 8
#define NUM_ALARM_REGS 7
#define DISABLE_ALARM_INT 0x3F
#define ENABLE_ALARM_INT 0xFF
#define ALARM_INT_STATUS BIT(4)
#define CLK32K_TEST_EN BIT(0)
#define CLK32K_TEST_START BIT(0)
#define CLK32K_TEST_STATUS BIT(1)
#define CLK32K_TEST_DONE BIT(2)
#define CLK32K_TEST_LEN 2
#define CLK32K_COMP_DIR_ADD BIT(7)
#define CLK32K_COMP_EN BIT(2)
#define CLK32K_NO_COMP 0x1
#define CLK32K_TEST_REF_CLK 25000000
struct rk630_rtc {
struct rk630 *rk630;
struct rtc_device *rtc;
int irq;
unsigned int flag;
};
/* Read current time and date in RTC */
static int rk630_rtc_readtime(struct device *dev, struct rtc_time *tm)
{
struct rk630_rtc *rk630_rtc = dev_get_drvdata(dev);
struct rk630 *rk630 = rk630_rtc->rk630;
u32 rtc_data[NUM_TIME_REGS];
int ret;
int yearl, yearh;
/* Force an update of the shadowed registers right now */
ret = regmap_update_bits(rk630->rtc, RTC_CTRL,
RTC_CTRL_REG_RTC_GET_TIME,
RTC_CTRL_REG_RTC_GET_TIME);
if (ret) {
dev_err(dev, "Failed to update bits rtc_ctrl: %d\n", ret);
return ret;
}
/*
* After we set the GET_TIME bit, the rtc time can't be read
* immediately. So we should wait up to 31.25 us, about one cycle of
* 32khz. If we clear the GET_TIME bit here, the time of i2c transfer
* certainly more than 31.25us: 16 * 2.5us at 400kHz bus frequency.
*/
ret = regmap_update_bits(rk630->rtc, RTC_CTRL,
RTC_CTRL_REG_RTC_GET_TIME,
0);
if (ret) {
dev_err(dev, "Failed to update bits rtc_ctrl: %d\n", ret);
return ret;
}
ret = regmap_bulk_read(rk630->rtc, RTC_SET_SECONDS,
rtc_data, NUM_TIME_REGS);
if (ret) {
dev_err(dev, "Failed to bulk read rtc_data: %d\n", ret);
return ret;
}
tm->tm_sec = bcd2bin(rtc_data[0] & SECONDS_REG_MSK);
tm->tm_min = bcd2bin(rtc_data[1] & MINUTES_REG_MAK);
tm->tm_hour = bcd2bin(rtc_data[2] & HOURS_REG_MSK);
tm->tm_mday = bcd2bin(rtc_data[3] & DAYS_REG_MSK);
tm->tm_mon = (bcd2bin(rtc_data[4] & MONTHS_REG_MSK)) - 1;
yearl = (bcd2bin(rtc_data[5] & YEARS_REG_MSK));
yearh = (bcd2bin(rtc_data[6] & YEARS_REG_MSK));
tm->tm_year = yearh * 100 + yearl + 100;
tm->tm_wday = bcd2bin(rtc_data[7] & WEEKS_REG_MSK);
dev_dbg(dev, "RTC date/time %4d-%02d-%02d(%d) %02d:%02d:%02d\n",
1900 + tm->tm_year, tm->tm_mon + 1, tm->tm_mday,
tm->tm_wday, tm->tm_hour, tm->tm_min, tm->tm_sec);
return ret;
}
/* Set current time and date in RTC */
static int rk630_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
struct rk630_rtc *rk630_rtc = dev_get_drvdata(dev);
struct rk630 *rk630 = rk630_rtc->rk630;
u32 rtc_data[NUM_TIME_REGS];
int ret;
int yearl, yearh;
dev_dbg(dev, "set RTC date/time %4d-%02d-%02d(%d) %02d:%02d:%02d\n",
1900 + tm->tm_year, tm->tm_mon + 1, tm->tm_mday,
tm->tm_wday, tm->tm_hour, tm->tm_min, tm->tm_sec);
rtc_data[0] = bin2bcd(tm->tm_sec);
rtc_data[1] = bin2bcd(tm->tm_min);
rtc_data[2] = bin2bcd(tm->tm_hour);
rtc_data[3] = bin2bcd(tm->tm_mday);
rtc_data[4] = bin2bcd(tm->tm_mon + 1);
if (tm->tm_year > 199) {
yearh = (tm->tm_year - 100) / 100;
yearl = tm->tm_year - 100 - yearh * 100;
} else {
yearh = 0;
yearl = tm->tm_year - 100 - yearh * 100;
}
rtc_data[5] = bin2bcd(yearl);
rtc_data[6] = bin2bcd(yearh);
rtc_data[7] = bin2bcd(tm->tm_wday);
/* Stop RTC while updating the RTC registers */
ret = regmap_update_bits(rk630->rtc, RTC_CTRL,
RTC_CTRL_REG_START_RTC, 0);
if (ret) {
dev_err(dev, "Failed to update bits rtc_ctrl: %d\n", ret);
return ret;
}
ret = regmap_bulk_write(rk630->rtc, RTC_SET_SECONDS,
rtc_data, NUM_TIME_REGS);
if (ret) {
dev_err(dev, "Failed to bull write rtc_data: %d\n", ret);
return ret;
}
/* Start RTC again */
ret = regmap_update_bits(rk630->rtc, RTC_CTRL,
RTC_CTRL_REG_RTC_READSEL_M |
RTC_CTRL_REG_START_RTC,
RTC_CTRL_REG_RTC_READSEL_M |
RTC_CTRL_REG_START_RTC);
if (ret) {
dev_err(dev, "Failed to update bits RTC control: %d\n", ret);
return ret;
}
return 0;
}
/* Read alarm time and date in RTC */
static int rk630_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
{
struct rk630_rtc *rk630_rtc = dev_get_drvdata(dev);
struct rk630 *rk630 = rk630_rtc->rk630;
u32 alrm_data[NUM_ALARM_REGS];
u32 int_reg;
int yearl, yearh;
int ret;
ret = regmap_bulk_read(rk630->rtc,
RTC_ALARM_SECONDS,
alrm_data, NUM_ALARM_REGS);
if (ret) {
dev_err(dev, "Failed to read RTC alarm date REG: %d\n", ret);
return ret;
}
alrm->time.tm_sec = bcd2bin(alrm_data[0] & SECONDS_REG_MSK);
alrm->time.tm_min = bcd2bin(alrm_data[1] & MINUTES_REG_MAK);
alrm->time.tm_hour = bcd2bin(alrm_data[2] & HOURS_REG_MSK);
alrm->time.tm_mday = bcd2bin(alrm_data[3] & DAYS_REG_MSK);
alrm->time.tm_mon = (bcd2bin(alrm_data[4] & MONTHS_REG_MSK)) - 1;
yearl = (bcd2bin(alrm_data[5] & YEARS_REG_MSK));
yearh = (bcd2bin(alrm_data[6] & YEARS_REG_MSK));
alrm->time.tm_year = yearh * 100 + yearl + 100;
ret = regmap_read(rk630->rtc, RTC_INT0_EN, &int_reg);
if (ret) {
dev_err(dev, "Failed to read RTC INT REG: %d\n", ret);
return ret;
}
dev_dbg(dev, "alrm read RTC date/time %4d-%02d-%02d(%d) %02d:%02d:%02d\n",
1900 + alrm->time.tm_year, alrm->time.tm_mon + 1,
alrm->time.tm_mday, alrm->time.tm_wday, alrm->time.tm_hour,
alrm->time.tm_min, alrm->time.tm_sec);
alrm->enabled = (int_reg & RTC_INT_REG_ALARM_EN) ? 1 : 0;
return 0;
}
static int rk630_rtc_stop_alarm(struct rk630_rtc *rk630_rtc)
{
struct rk630 *rk630 = rk630_rtc->rk630;
int ret;
ret = regmap_write(rk630->rtc, RTC_INT0_EN, DISABLE_ALARM_INT);
return ret;
}
static int rk630_rtc_start_alarm(struct rk630_rtc *rk630_rtc)
{
struct rk630 *rk630 = rk630_rtc->rk630;
int ret = 0;
ret = regmap_write(rk630->rtc, RTC_STATUS0, RTC_STATUS_MASK);
if (ret) {
dev_err(rk630->dev, "Failed to write RTC_STATUS0: %d\n", ret);
return ret;
}
ret = regmap_write(rk630->rtc, RTC_STATUS0, 0);
if (ret) {
dev_err(rk630->dev, "Failed to write RTC_STATUS0: %d\n", ret);
return ret;
}
ret = regmap_write(rk630->rtc, RTC_INT0_EN, ENABLE_ALARM_INT);
if (ret) {
dev_err(rk630->dev, "Failed to write RTC_INT0_EN: %d\n", ret);
return ret;
}
return ret;
}
static int rk630_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
{
struct rk630_rtc *rk630_rtc = dev_get_drvdata(dev);
struct rk630 *rk630 = rk630_rtc->rk630;
u32 alrm_data[NUM_ALARM_REGS];
int yearl, yearh;
int ret;
ret = rk630_rtc_stop_alarm(rk630_rtc);
if (ret) {
dev_err(dev, "Failed to stop alarm: %d\n", ret);
return ret;
}
dev_dbg(dev, "alrm set RTC date/time %4d-%02d-%02d(%d) %02d:%02d:%02d\n",
1900 + alrm->time.tm_year, alrm->time.tm_mon + 1,
alrm->time.tm_mday, alrm->time.tm_wday, alrm->time.tm_hour,
alrm->time.tm_min, alrm->time.tm_sec);
alrm_data[0] = bin2bcd(alrm->time.tm_sec);
alrm_data[1] = bin2bcd(alrm->time.tm_min);
alrm_data[2] = bin2bcd(alrm->time.tm_hour);
alrm_data[3] = bin2bcd(alrm->time.tm_mday);
alrm_data[4] = bin2bcd(alrm->time.tm_mon + 1);
if (alrm->time.tm_year > 199) {
yearh = (alrm->time.tm_year - 100) / 100;
yearl = alrm->time.tm_year - 100 - yearh * 100;
} else {
yearh = 0;
yearl = alrm->time.tm_year - 100 - yearh * 100;
}
alrm_data[5] = bin2bcd(yearl);
alrm_data[6] = bin2bcd(yearh);
ret = regmap_bulk_write(rk630->rtc,
RTC_ALARM_SECONDS,
alrm_data, NUM_ALARM_REGS);
if (ret) {
dev_err(dev, "Failed to bulk write: %d\n", ret);
return ret;
}
if (alrm->enabled) {
ret = rk630_rtc_start_alarm(rk630_rtc);
if (ret) {
dev_err(dev, "Failed to start alarm: %d\n", ret);
return ret;
}
}
return 0;
}
static int rk630_rtc_alarm_irq_enable(struct device *dev,
unsigned int enabled)
{
struct rk630_rtc *rk630_rtc = dev_get_drvdata(dev);
if (enabled)
return rk630_rtc_start_alarm(rk630_rtc);
return rk630_rtc_stop_alarm(rk630_rtc);
}
/*
* We will just handle setting the frequency and make use the framework for
* reading the periodic interrupts.
*
*/
static irqreturn_t rk630_alarm_irq(int irq, void *data)
{
struct rk630_rtc *rk630_rtc = data;
struct rk630 *rk630 = rk630_rtc->rk630;
int ret, status;
ret = regmap_read(rk630->rtc, RTC_STATUS0, &status);
if (ret) {
pr_err("Failed to read RTC INT REG: %d\n", ret);
return ret;
}
ret = regmap_write(rk630->rtc, RTC_STATUS0, status);
if (ret) {
pr_err("%s:Failed to update RTC status: %d\n", __func__, ret);
return ret;
}
ret = regmap_write(rk630->rtc, RTC_STATUS0, 0x0);
if (ret) {
pr_err("%s:Failed to update RTC status: %d\n", __func__, ret);
return ret;
}
if (status & ALARM_INT_STATUS) {
pr_info("Alarm by: %s\n", __func__);
rtc_update_irq(rk630_rtc->rtc, 1, RTC_IRQF | RTC_AF);
}
return IRQ_HANDLED;
}
static const struct rtc_class_ops rk630_rtc_ops = {
.read_time = rk630_rtc_readtime,
.set_time = rk630_rtc_set_time,
.read_alarm = rk630_rtc_readalarm,
.set_alarm = rk630_rtc_setalarm,
.alarm_irq_enable = rk630_rtc_alarm_irq_enable,
};
/*
* Due to the analog generator 32k clock affected by
* temperature, voltage, clock precision need test
* with the environment change. In rtc test,
* use 24M clock as reference clock to measure the 32k clock.
* Before start test 32k clock, we should enable clk32k test(0x80),
* and configure test length, when rtc test done(0x84[2]),
* latch the 24M clock domain counter,
* and read out the counter from rtc_test
* registers(0x8c~0x98) via apb bus.
* In RTC digital design, we set three level compensation,
* the compensation value due to the
* RTC 32k clock test result, and if we need compensation,
* we need configure the compensation enable bit.
* Comp every hour, compensation at last minute every hour,
* and support add time and sub time by the MSB bit.
* Comp every day, compensation at last minute in last hour every day,
* and support add time and sub time by the MSB bit.
* Comp every month, compensation at last minute
* in last hour in last day every month,
* and support add time and sub time by the MSB bit.
*/
static int rk630_rtc_compensation(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct rk630_rtc *rk630_rtc = dev_get_drvdata(&pdev->dev);
struct rk630 *rk630 = rk630_rtc->rk630;
u64 camp;
u32 count[4], counts, g_ref, tcamp;
int ret, done = 0, trim_dir, c_hour,
c_day, c_det_day, c_mon, c_det_mon;
ret = regmap_write(rk630->rtc, RTC_CLK32K_TEST, CLK32K_TEST_EN);
if (ret) {
dev_err(dev,
"%s:Failed to update RTC CLK32K TEST: %d\n",
__func__, ret);
return ret;
}
ret = regmap_write(rk630->rtc, RTC_TEST_LEN, CLK32K_TEST_LEN);
if (ret) {
dev_err(dev,
"%s:Failed to update RTC CLK32K TEST LEN: %d\n",
__func__, ret);
return ret;
}
ret = regmap_write(rk630->rtc, RTC_TEST_ST, CLK32K_TEST_START);
if (ret) {
dev_err(dev,
"%s:Failed to update RTC CLK32K TEST STATUS : %d\n",
__func__, ret);
return ret;
}
while (!done) {
ret = regmap_read(rk630->rtc, RTC_TEST_ST, &done);
if (ret) {
dev_err(dev,
"Failed to read RTC CLK32K TEST STATUS: %d\n",
ret);
return ret;
}
done = (done & CLK32K_TEST_DONE) >> 2;
udelay(1);
}
ret = regmap_bulk_read(rk630->rtc, RTC_CNT_0, count, 4);
if (ret) {
dev_err(dev, "Failed to read RTC count REG: %d\n", ret);
return ret;
}
counts = count[0] | (count[1] << 8) |
(count[2] << 16) | (count[3] << 24);
g_ref = CLK32K_TEST_REF_CLK * (CLK32K_TEST_LEN + 1);
if (counts > g_ref) {
trim_dir = 0;
camp = 36ULL * (32768 * (counts - g_ref));
do_div(camp, (g_ref / 100));
} else {
trim_dir = CLK32K_COMP_DIR_ADD;
camp = 36ULL * (32768 * (g_ref - counts));
do_div(camp, (g_ref / 100));
}
tcamp = (u32)camp;
c_hour = DIV_ROUND_CLOSEST(tcamp, 32768);
c_day = DIV_ROUND_CLOSEST(24 * tcamp, 32768);
c_mon = DIV_ROUND_CLOSEST(30 * 24 * tcamp, 32768);
if (c_hour > 1)
regmap_write(rk630->rtc, RTC_COMP_H, bin2bcd((c_hour - 1)) | trim_dir);
else
regmap_write(rk630->rtc, RTC_COMP_H, CLK32K_NO_COMP);
if (c_day > c_hour * 23) {
c_det_day = c_day - c_hour * 23;
trim_dir = CLK32K_COMP_DIR_ADD;
} else {
c_det_day = c_hour * 24 - c_day;
trim_dir = 0;
}
if (c_det_day > 1)
regmap_write(rk630->rtc, RTC_COMP_D,
bin2bcd((c_det_day - 1)) | trim_dir);
else
regmap_write(rk630->rtc, RTC_COMP_D, CLK32K_NO_COMP);
if (c_mon > (29 * c_day + 23 * c_hour)) {
c_det_mon = c_mon - 29 * c_day - 23 * c_hour;
trim_dir = CLK32K_COMP_DIR_ADD;
} else {
c_det_mon = 29 * c_day + 23 * c_hour - c_mon;
trim_dir = 0;
}
if (c_det_mon)
regmap_write(rk630->rtc, RTC_COMP_M,
bin2bcd((c_det_mon - 1)) | trim_dir);
else
regmap_write(rk630->rtc, RTC_COMP_M, CLK32K_NO_COMP);
ret = regmap_read(rk630->rtc, RTC_CTRL, &done);
if (ret) {
dev_err(dev, "Failed to read RTC_CTRL: %d\n",
ret);
return ret;
}
ret = regmap_update_bits(rk630->rtc, RTC_CTRL,
CLK32K_COMP_EN,
CLK32K_COMP_EN);
if (ret) {
dev_err(dev,
"%s:Failed to update RTC CTRL : %d\n", __func__, ret);
return ret;
}
return 0;
}
/* Enable the alarm if it should be enabled (in case it was disabled to
* prevent use as a wake source).
*/
#ifdef CONFIG_PM_SLEEP
/* Turn off the alarm if it should not be a wake source. */
static int rk630_rtc_suspend(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct rk630_rtc *rk630_rtc = dev_get_drvdata(&pdev->dev);
if (device_may_wakeup(dev))
enable_irq_wake(rk630_rtc->irq);
regmap_write(rk630_rtc->rk630->grf,
PLUMAGE_GRF_SOC_CON0,
RTC_CLAMP_EN(0));
return 0;
}
/* Enable the alarm if it should be enabled (in case it was disabled to
* prevent use as a wake source).
*/
static int rk630_rtc_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct rk630_rtc *rk630_rtc = dev_get_drvdata(&pdev->dev);
if (device_may_wakeup(dev))
disable_irq_wake(rk630_rtc->irq);
regmap_write(rk630_rtc->rk630->grf,
PLUMAGE_GRF_SOC_CON0,
RTC_CLAMP_EN(1));
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(rk630_rtc_pm_ops, rk630_rtc_suspend, rk630_rtc_resume);
static int rk630_rtc_probe(struct platform_device *pdev)
{
struct rk630 *rk630 = dev_get_drvdata(pdev->dev.parent);
struct rk630_rtc *rk630_rtc;
int ret;
struct rtc_time tm_read, tm = {
.tm_wday = 0,
.tm_year = 121,
.tm_mon = 0,
.tm_mday = 1,
.tm_hour = 12,
.tm_min = 0,
.tm_sec = 0,
};
rk630_rtc = devm_kzalloc(&pdev->dev, sizeof(*rk630_rtc), GFP_KERNEL);
if (!rk630_rtc)
return -ENOMEM;
platform_set_drvdata(pdev, rk630_rtc);
rk630_rtc->rk630 = rk630;
regmap_write(rk630->grf, PLUMAGE_GRF_SOC_CON0, RTC_CLAMP_EN(1));
/* setting d2a_lp_xo_start_mir */
regmap_write(rk630->rtc, RTC_XO_TRIM0, RTC_XO_START_MIR);
regmap_write(rk630->rtc, RTC_ANALOG_TEST, RTC_VREF_INIT);
rk630_rtc_compensation(&pdev->dev);
/* start rtc running by default, and use shadowed timer. */
ret = regmap_update_bits(rk630->rtc, RTC_CTRL,
RTC_CTRL_REG_RTC_READSEL_M |
RTC_CTRL_REG_START_RTC,
RTC_CTRL_REG_RTC_READSEL_M |
RTC_CTRL_REG_START_RTC);
if (ret) {
dev_err(&pdev->dev,
"Failed to write RTC control: %d\n", ret);
return ret;
}
ret = regmap_write(rk630->rtc, RTC_STATUS0,
RTC_STATUS_MASK);
if (ret) {
dev_err(&pdev->dev,
"Failed to write RTC status0: %d\n", ret);
return ret;
}
ret = regmap_write(rk630->rtc, RTC_STATUS0, 0);
if (ret) {
dev_err(&pdev->dev,
"Failed to write RTC status0: %d\n", ret);
return ret;
}
device_init_wakeup(&pdev->dev, 1);
rk630_rtc_readtime(&pdev->dev, &tm_read);
if (rtc_valid_tm(&tm_read) != 0)
rk630_rtc_set_time(&pdev->dev, &tm);
rk630_rtc->rtc = devm_rtc_allocate_device(&pdev->dev);
if (IS_ERR(rk630_rtc->rtc))
return PTR_ERR(rk630_rtc->rtc);
rk630_rtc->rtc->ops = &rk630_rtc_ops;
/* request alarm irq of rk630 */
ret = devm_request_threaded_irq(&pdev->dev, rk630->irq, NULL,
rk630_alarm_irq,
IRQF_TRIGGER_LOW | IRQF_ONESHOT |
IRQF_SHARED,
"RTC alarm", rk630_rtc);
if (ret) {
dev_err(&pdev->dev, "Failed to request alarm IRQ %d: %d\n",
rk630_rtc->irq, ret);
return ret;
}
return rtc_register_device(rk630_rtc->rtc);
}
static struct platform_driver rk630_rtc_driver = {
.probe = rk630_rtc_probe,
.driver = {
.name = "rk630-rtc",
.pm = &rk630_rtc_pm_ops,
},
};
module_platform_driver(rk630_rtc_driver);
MODULE_DESCRIPTION("RTC driver for the rk630");
MODULE_AUTHOR("Zhang Qing <zhangqing@rock-chips.com>");
MODULE_LICENSE("GPL");