+++ /dev/null
-/*
- * RTC driver for Maxim MAX77802
- *
- * Copyright (C) 2013 Google, Inc
- *
- * Copyright (C) 2012 Samsung Electronics Co.Ltd
- *
- * based on rtc-max8997.c
- *
- * 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/slab.h>
-#include <linux/rtc.h>
-#include <linux/delay.h>
-#include <linux/mutex.h>
-#include <linux/module.h>
-#include <linux/platform_device.h>
-#include <linux/mfd/max77686-private.h>
-#include <linux/irqdomain.h>
-#include <linux/regmap.h>
-
-/* RTC Control Register */
-#define BCD_EN_SHIFT 0
-#define BCD_EN_MASK (1 << BCD_EN_SHIFT)
-#define MODEL24_SHIFT 1
-#define MODEL24_MASK (1 << MODEL24_SHIFT)
-/* RTC Update Register1 */
-#define RTC_UDR_SHIFT 0
-#define RTC_UDR_MASK (1 << RTC_UDR_SHIFT)
-#define RTC_RBUDR_SHIFT 4
-#define RTC_RBUDR_MASK (1 << RTC_RBUDR_SHIFT)
-/* RTC Hour register */
-#define HOUR_PM_SHIFT 6
-#define HOUR_PM_MASK (1 << HOUR_PM_SHIFT)
-/* RTC Alarm Enable */
-#define ALARM_ENABLE_SHIFT 7
-#define ALARM_ENABLE_MASK (1 << ALARM_ENABLE_SHIFT)
-
-/* For the RTCAE1 register, we write this value to enable the alarm */
-#define ALARM_ENABLE_VALUE 0x77
-
-#define MAX77802_RTC_UPDATE_DELAY_US 200
-
-enum {
- RTC_SEC = 0,
- RTC_MIN,
- RTC_HOUR,
- RTC_WEEKDAY,
- RTC_MONTH,
- RTC_YEAR,
- RTC_DATE,
- RTC_NR_TIME
-};
-
-struct max77802_rtc_info {
- struct device *dev;
- struct max77686_dev *max77802;
- struct i2c_client *rtc;
- struct rtc_device *rtc_dev;
- struct mutex lock;
-
- struct regmap *regmap;
-
- int virq;
- int rtc_24hr_mode;
-};
-
-enum MAX77802_RTC_OP {
- MAX77802_RTC_WRITE,
- MAX77802_RTC_READ,
-};
-
-static void max77802_rtc_data_to_tm(u8 *data, struct rtc_time *tm,
- int rtc_24hr_mode)
-{
- tm->tm_sec = data[RTC_SEC] & 0xff;
- tm->tm_min = data[RTC_MIN] & 0xff;
- if (rtc_24hr_mode)
- tm->tm_hour = data[RTC_HOUR] & 0x1f;
- else {
- tm->tm_hour = data[RTC_HOUR] & 0x0f;
- if (data[RTC_HOUR] & HOUR_PM_MASK)
- tm->tm_hour += 12;
- }
-
- /* Only a single bit is set in data[], so fls() would be equivalent */
- tm->tm_wday = ffs(data[RTC_WEEKDAY] & 0xff) - 1;
- tm->tm_mday = data[RTC_DATE] & 0x1f;
- tm->tm_mon = (data[RTC_MONTH] & 0x0f) - 1;
-
- tm->tm_year = data[RTC_YEAR] & 0xff;
- tm->tm_yday = 0;
- tm->tm_isdst = 0;
-}
-
-static int max77802_rtc_tm_to_data(struct rtc_time *tm, u8 *data)
-{
- data[RTC_SEC] = tm->tm_sec;
- data[RTC_MIN] = tm->tm_min;
- data[RTC_HOUR] = tm->tm_hour;
- data[RTC_WEEKDAY] = 1 << tm->tm_wday;
- data[RTC_DATE] = tm->tm_mday;
- data[RTC_MONTH] = tm->tm_mon + 1;
- data[RTC_YEAR] = tm->tm_year;
-
- return 0;
-}
-
-static int max77802_rtc_update(struct max77802_rtc_info *info,
- enum MAX77802_RTC_OP op)
-{
- int ret;
- unsigned int data;
-
- if (op == MAX77802_RTC_WRITE)
- data = 1 << RTC_UDR_SHIFT;
- else
- data = 1 << RTC_RBUDR_SHIFT;
-
- ret = regmap_update_bits(info->max77802->regmap,
- MAX77802_RTC_UPDATE0, data, data);
- if (ret < 0)
- dev_err(info->dev, "%s: fail to write update reg(ret=%d, data=0x%x)\n",
- __func__, ret, data);
- else {
- /* Minimum delay required before RTC update. */
- usleep_range(MAX77802_RTC_UPDATE_DELAY_US,
- MAX77802_RTC_UPDATE_DELAY_US * 2);
- }
-
- return ret;
-}
-
-static int max77802_rtc_read_time(struct device *dev, struct rtc_time *tm)
-{
- struct max77802_rtc_info *info = dev_get_drvdata(dev);
- u8 data[RTC_NR_TIME];
- int ret;
-
- mutex_lock(&info->lock);
-
- ret = max77802_rtc_update(info, MAX77802_RTC_READ);
- if (ret < 0)
- goto out;
-
- ret = regmap_bulk_read(info->max77802->regmap,
- MAX77802_RTC_SEC, data, RTC_NR_TIME);
- if (ret < 0) {
- dev_err(info->dev, "%s: fail to read time reg(%d)\n", __func__,
- ret);
- goto out;
- }
-
- max77802_rtc_data_to_tm(data, tm, info->rtc_24hr_mode);
-
- ret = rtc_valid_tm(tm);
-
-out:
- mutex_unlock(&info->lock);
- return ret;
-}
-
-static int max77802_rtc_set_time(struct device *dev, struct rtc_time *tm)
-{
- struct max77802_rtc_info *info = dev_get_drvdata(dev);
- u8 data[RTC_NR_TIME];
- int ret;
-
- ret = max77802_rtc_tm_to_data(tm, data);
- if (ret < 0)
- return ret;
-
- mutex_lock(&info->lock);
-
- ret = regmap_bulk_write(info->max77802->regmap,
- MAX77802_RTC_SEC, data, RTC_NR_TIME);
- if (ret < 0) {
- dev_err(info->dev, "%s: fail to write time reg(%d)\n", __func__,
- ret);
- goto out;
- }
-
- ret = max77802_rtc_update(info, MAX77802_RTC_WRITE);
-
-out:
- mutex_unlock(&info->lock);
- return ret;
-}
-
-static int max77802_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
-{
- struct max77802_rtc_info *info = dev_get_drvdata(dev);
- u8 data[RTC_NR_TIME];
- unsigned int val;
- int ret;
-
- mutex_lock(&info->lock);
-
- ret = max77802_rtc_update(info, MAX77802_RTC_READ);
- if (ret < 0)
- goto out;
-
- ret = regmap_bulk_read(info->max77802->regmap,
- MAX77802_ALARM1_SEC, data, RTC_NR_TIME);
- if (ret < 0) {
- dev_err(info->dev, "%s:%d fail to read alarm reg(%d)\n",
- __func__, __LINE__, ret);
- goto out;
- }
-
- max77802_rtc_data_to_tm(data, &alrm->time, info->rtc_24hr_mode);
-
- alrm->enabled = 0;
- ret = regmap_read(info->max77802->regmap,
- MAX77802_RTC_AE1, &val);
- if (ret < 0) {
- dev_err(info->dev, "%s:%d fail to read alarm enable(%d)\n",
- __func__, __LINE__, ret);
- goto out;
- }
- if (val)
- alrm->enabled = 1;
-
- alrm->pending = 0;
- ret = regmap_read(info->max77802->regmap, MAX77802_REG_STATUS2, &val);
- if (ret < 0) {
- dev_err(info->dev, "%s:%d fail to read status2 reg(%d)\n",
- __func__, __LINE__, ret);
- goto out;
- }
-
- if (val & (1 << 2)) /* RTCA1 */
- alrm->pending = 1;
-
-out:
- mutex_unlock(&info->lock);
- return 0;
-}
-
-static int max77802_rtc_stop_alarm(struct max77802_rtc_info *info)
-{
- int ret;
-
- if (!mutex_is_locked(&info->lock))
- dev_warn(info->dev, "%s: should have mutex locked\n", __func__);
-
- ret = max77802_rtc_update(info, MAX77802_RTC_READ);
- if (ret < 0)
- goto out;
-
- ret = regmap_write(info->max77802->regmap,
- MAX77802_RTC_AE1, 0);
- if (ret < 0) {
- dev_err(info->dev, "%s: fail to write alarm reg(%d)\n",
- __func__, ret);
- goto out;
- }
-
- ret = max77802_rtc_update(info, MAX77802_RTC_WRITE);
-out:
- return ret;
-}
-
-static int max77802_rtc_start_alarm(struct max77802_rtc_info *info)
-{
- int ret;
-
- if (!mutex_is_locked(&info->lock))
- dev_warn(info->dev, "%s: should have mutex locked\n",
- __func__);
-
- ret = max77802_rtc_update(info, MAX77802_RTC_READ);
- if (ret < 0)
- goto out;
-
- ret = regmap_write(info->max77802->regmap,
- MAX77802_RTC_AE1,
- ALARM_ENABLE_VALUE);
-
- if (ret < 0) {
- dev_err(info->dev, "%s: fail to read alarm reg(%d)\n",
- __func__, ret);
- goto out;
- }
-
- ret = max77802_rtc_update(info, MAX77802_RTC_WRITE);
-out:
- return ret;
-}
-
-static int max77802_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
-{
- struct max77802_rtc_info *info = dev_get_drvdata(dev);
- u8 data[RTC_NR_TIME];
- int ret;
-
- ret = max77802_rtc_tm_to_data(&alrm->time, data);
- if (ret < 0)
- return ret;
-
- mutex_lock(&info->lock);
-
- ret = max77802_rtc_stop_alarm(info);
- if (ret < 0)
- goto out;
-
- ret = regmap_bulk_write(info->max77802->regmap,
- MAX77802_ALARM1_SEC, data, RTC_NR_TIME);
-
- if (ret < 0) {
- dev_err(info->dev, "%s: fail to write alarm reg(%d)\n",
- __func__, ret);
- goto out;
- }
-
- ret = max77802_rtc_update(info, MAX77802_RTC_WRITE);
- if (ret < 0)
- goto out;
-
- if (alrm->enabled)
- ret = max77802_rtc_start_alarm(info);
-out:
- mutex_unlock(&info->lock);
- return ret;
-}
-
-static int max77802_rtc_alarm_irq_enable(struct device *dev,
- unsigned int enabled)
-{
- struct max77802_rtc_info *info = dev_get_drvdata(dev);
- int ret;
-
- mutex_lock(&info->lock);
- if (enabled)
- ret = max77802_rtc_start_alarm(info);
- else
- ret = max77802_rtc_stop_alarm(info);
- mutex_unlock(&info->lock);
-
- return ret;
-}
-
-static irqreturn_t max77802_rtc_alarm_irq(int irq, void *data)
-{
- struct max77802_rtc_info *info = data;
-
- dev_dbg(info->dev, "%s:irq(%d)\n", __func__, irq);
-
- rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF);
-
- return IRQ_HANDLED;
-}
-
-static const struct rtc_class_ops max77802_rtc_ops = {
- .read_time = max77802_rtc_read_time,
- .set_time = max77802_rtc_set_time,
- .read_alarm = max77802_rtc_read_alarm,
- .set_alarm = max77802_rtc_set_alarm,
- .alarm_irq_enable = max77802_rtc_alarm_irq_enable,
-};
-
-static int max77802_rtc_init_reg(struct max77802_rtc_info *info)
-{
- u8 data[2];
- int ret;
-
- max77802_rtc_update(info, MAX77802_RTC_READ);
-
- /* Set RTC control register : Binary mode, 24hour mdoe */
- data[0] = (1 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
- data[1] = (0 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
-
- info->rtc_24hr_mode = 1;
-
- ret = regmap_bulk_write(info->max77802->regmap,
- MAX77802_RTC_CONTROLM, data, ARRAY_SIZE(data));
- if (ret < 0) {
- dev_err(info->dev, "%s: fail to write controlm reg(%d)\n",
- __func__, ret);
- return ret;
- }
-
- ret = max77802_rtc_update(info, MAX77802_RTC_WRITE);
- return ret;
-}
-
-static int max77802_rtc_probe(struct platform_device *pdev)
-{
- struct max77686_dev *max77802 = dev_get_drvdata(pdev->dev.parent);
- struct max77802_rtc_info *info;
- int ret;
-
- dev_dbg(&pdev->dev, "%s\n", __func__);
-
- info = devm_kzalloc(&pdev->dev, sizeof(struct max77802_rtc_info),
- GFP_KERNEL);
- if (!info)
- return -ENOMEM;
-
- mutex_init(&info->lock);
- info->dev = &pdev->dev;
- info->max77802 = max77802;
- info->rtc = max77802->i2c;
-
- platform_set_drvdata(pdev, info);
-
- ret = max77802_rtc_init_reg(info);
-
- if (ret < 0) {
- dev_err(&pdev->dev, "Failed to initialize RTC reg:%d\n", ret);
- return ret;
- }
-
- device_init_wakeup(&pdev->dev, 1);
-
- info->rtc_dev = devm_rtc_device_register(&pdev->dev, "max77802-rtc",
- &max77802_rtc_ops, THIS_MODULE);
-
- if (IS_ERR(info->rtc_dev)) {
- ret = PTR_ERR(info->rtc_dev);
- dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
- if (ret == 0)
- ret = -EINVAL;
- return ret;
- }
-
- if (!max77802->rtc_irq_data) {
- dev_err(&pdev->dev, "No RTC regmap IRQ chip\n");
- return -EINVAL;
- }
-
- info->virq = regmap_irq_get_virq(max77802->rtc_irq_data,
- MAX77686_RTCIRQ_RTCA1);
-
- if (info->virq <= 0) {
- dev_err(&pdev->dev, "Failed to get virtual IRQ %d\n",
- MAX77686_RTCIRQ_RTCA1);
- return -EINVAL;
- }
-
- ret = devm_request_threaded_irq(&pdev->dev, info->virq, NULL,
- max77802_rtc_alarm_irq, 0, "rtc-alarm1",
- info);
- if (ret < 0)
- dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n",
- info->virq, ret);
-
- return ret;
-}
-
-#ifdef CONFIG_PM_SLEEP
-static int max77802_rtc_suspend(struct device *dev)
-{
- if (device_may_wakeup(dev)) {
- struct max77802_rtc_info *info = dev_get_drvdata(dev);
-
- return enable_irq_wake(info->virq);
- }
-
- return 0;
-}
-
-static int max77802_rtc_resume(struct device *dev)
-{
- if (device_may_wakeup(dev)) {
- struct max77802_rtc_info *info = dev_get_drvdata(dev);
-
- return disable_irq_wake(info->virq);
- }
-
- return 0;
-}
-#endif
-
-static SIMPLE_DEV_PM_OPS(max77802_rtc_pm_ops,
- max77802_rtc_suspend, max77802_rtc_resume);
-
-static const struct platform_device_id rtc_id[] = {
- { "max77802-rtc", 0 },
- {},
-};
-MODULE_DEVICE_TABLE(platform, rtc_id);
-
-static struct platform_driver max77802_rtc_driver = {
- .driver = {
- .name = "max77802-rtc",
- .pm = &max77802_rtc_pm_ops,
- },
- .probe = max77802_rtc_probe,
- .id_table = rtc_id,
-};
-
-module_platform_driver(max77802_rtc_driver);
-
-MODULE_DESCRIPTION("Maxim MAX77802 RTC driver");
-MODULE_AUTHOR("Simon Glass <sjg@chromium.org>");
-MODULE_LICENSE("GPL");
projects / karo-tx-linux.git / commitdiff