--- /dev/null
+/*
+ * rtc-palmas.c -- Palmas Real Time Clock driver.
+
+ * RTC driver for TI Palma series devices like TPS65913,
+ * TPS65914 power management IC.
+ *
+ * Copyright (c) 2012, NVIDIA Corporation.
+ *
+ * Author: Laxman Dewangan <ldewangan@nvidia.com>
+ *
+ * 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 version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
+ * whether express or implied; 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
+ */
+
+#include <linux/bcd.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/mfd/palmas.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/rtc.h>
+#include <linux/types.h>
+#include <linux/platform_device.h>
+#include <linux/pm.h>
+
+struct palmas_rtc {
+ struct rtc_device *rtc;
+ struct device *dev;
+ unsigned int irq;
+};
+
+/* Total number of RTC registers needed to set time*/
+#define PALMAS_NUM_TIME_REGS (PALMAS_YEARS_REG - PALMAS_SECONDS_REG + 1)
+
+static int palmas_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ unsigned char rtc_data[PALMAS_NUM_TIME_REGS];
+ struct palmas *palmas = dev_get_drvdata(dev->parent);
+ int ret;
+
+ /* Copy RTC counting registers to static registers or latches */
+ ret = palmas_update_bits(palmas, PALMAS_RTC_BASE, PALMAS_RTC_CTRL_REG,
+ PALMAS_RTC_CTRL_REG_GET_TIME, PALMAS_RTC_CTRL_REG_GET_TIME);
+ if (ret < 0) {
+ dev_err(dev, "RTC CTRL reg update failed, err: %d\n", ret);
+ return ret;
+ }
+
+ ret = palmas_bulk_read(palmas, PALMAS_RTC_BASE, PALMAS_SECONDS_REG,
+ rtc_data, PALMAS_NUM_TIME_REGS);
+ if (ret < 0) {
+ dev_err(dev, "RTC_SECONDS reg read failed, err = %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 palmas_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ unsigned char rtc_data[PALMAS_NUM_TIME_REGS];
+ struct palmas *palmas = dev_get_drvdata(dev->parent);
+ int ret;
+
+ 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);
+ rtc_data[5] = bin2bcd(tm->tm_year - 100);
+
+ /* Stop RTC while updating the RTC time registers */
+ ret = palmas_update_bits(palmas, PALMAS_RTC_BASE, PALMAS_RTC_CTRL_REG,
+ PALMAS_RTC_CTRL_REG_STOP_RTC, 0);
+ if (ret < 0) {
+ dev_err(dev, "RTC stop failed, err = %d\n", ret);
+ return ret;
+ }
+
+ ret = palmas_bulk_write(palmas, PALMAS_RTC_BASE, PALMAS_SECONDS_REG,
+ rtc_data, PALMAS_NUM_TIME_REGS);
+ if (ret < 0) {
+ dev_err(dev, "RTC_SECONDS reg write failed, err = %d\n", ret);
+ return ret;
+ }
+
+ /* Start back RTC */
+ ret = palmas_update_bits(palmas, PALMAS_RTC_BASE, PALMAS_RTC_CTRL_REG,
+ PALMAS_RTC_CTRL_REG_STOP_RTC, PALMAS_RTC_CTRL_REG_STOP_RTC);
+ if (ret < 0)
+ dev_err(dev, "RTC start failed, err = %d\n", ret);
+ return ret;
+}
+
+static int palmas_rtc_alarm_irq_enable(struct device *dev, unsigned enabled)
+{
+ struct palmas *palmas = dev_get_drvdata(dev->parent);
+ u8 val;
+
+ val = enabled ? PALMAS_RTC_INTERRUPTS_REG_IT_ALARM : 0;
+ return palmas_write(palmas, PALMAS_RTC_BASE,
+ PALMAS_RTC_INTERRUPTS_REG, val);
+}
+
+static int palmas_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
+{
+ unsigned char alarm_data[PALMAS_NUM_TIME_REGS];
+ u32 int_val;
+ struct palmas *palmas = dev_get_drvdata(dev->parent);
+ int ret;
+
+ ret = palmas_bulk_read(palmas, PALMAS_RTC_BASE,
+ PALMAS_ALARM_SECONDS_REG,
+ alarm_data, PALMAS_NUM_TIME_REGS);
+ if (ret < 0) {
+ dev_err(dev, "RTC_ALARM_SECONDS read failed, err = %d\n", ret);
+ return ret;
+ }
+
+ alm->time.tm_sec = bcd2bin(alarm_data[0]);
+ alm->time.tm_min = bcd2bin(alarm_data[1]);
+ alm->time.tm_hour = bcd2bin(alarm_data[2]);
+ alm->time.tm_mday = bcd2bin(alarm_data[3]);
+ alm->time.tm_mon = bcd2bin(alarm_data[4]) - 1;
+ alm->time.tm_year = bcd2bin(alarm_data[5]) + 100;
+
+ ret = palmas_read(palmas, PALMAS_RTC_BASE, PALMAS_RTC_INTERRUPTS_REG,
+ &int_val);
+ if (ret < 0) {
+ dev_err(dev, "RTC_INTERRUPTS reg read failed, err = %d\n", ret);
+ return ret;
+ }
+
+ if (int_val & PALMAS_RTC_INTERRUPTS_REG_IT_ALARM)
+ alm->enabled = 1;
+ return ret;
+}
+
+static int palmas_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
+{
+ unsigned char alarm_data[PALMAS_NUM_TIME_REGS];
+ struct palmas *palmas = dev_get_drvdata(dev->parent);
+ int ret;
+
+ ret = palmas_rtc_alarm_irq_enable(dev, 0);
+ if (ret < 0) {
+ dev_err(dev, "Disable RTC alarm failed\n");
+ return ret;
+ }
+
+ alarm_data[0] = bin2bcd(alm->time.tm_sec);
+ alarm_data[1] = bin2bcd(alm->time.tm_min);
+ alarm_data[2] = bin2bcd(alm->time.tm_hour);
+ alarm_data[3] = bin2bcd(alm->time.tm_mday);
+ alarm_data[4] = bin2bcd(alm->time.tm_mon + 1);
+ alarm_data[5] = bin2bcd(alm->time.tm_year - 100);
+
+ ret = palmas_bulk_write(palmas, PALMAS_RTC_BASE,
+ PALMAS_ALARM_SECONDS_REG, alarm_data, PALMAS_NUM_TIME_REGS);
+ if (ret < 0) {
+ dev_err(dev, "ALARM_SECONDS_REG write failed, err = %d\n", ret);
+ return ret;
+ }
+
+ if (alm->enabled)
+ ret = palmas_rtc_alarm_irq_enable(dev, 1);
+ return ret;
+}
+
+static int palmas_clear_interrupts(struct device *dev)
+{
+ struct palmas *palmas = dev_get_drvdata(dev->parent);
+ unsigned int rtc_reg;
+ int ret;
+
+ ret = palmas_read(palmas, PALMAS_RTC_BASE, PALMAS_RTC_STATUS_REG,
+ &rtc_reg);
+ if (ret < 0) {
+ dev_err(dev, "RTC_STATUS read failed, err = %d\n", ret);
+ return ret;
+ }
+
+ ret = palmas_write(palmas, PALMAS_RTC_BASE, PALMAS_RTC_STATUS_REG,
+ rtc_reg);
+ if (ret < 0) {
+ dev_err(dev, "RTC_STATUS write failed, err = %d\n", ret);
+ return ret;
+ }
+ return 0;
+}
+
+static irqreturn_t palmas_rtc_interrupt(int irq, void *context)
+{
+ struct palmas_rtc *palmas_rtc = context;
+ struct device *dev = palmas_rtc->dev;
+ int ret;
+
+ ret = palmas_clear_interrupts(dev);
+ if (ret < 0) {
+ dev_err(dev, "RTC interrupt clear failed, err = %d\n", ret);
+ return IRQ_NONE;
+ }
+
+ rtc_update_irq(palmas_rtc->rtc, 1, RTC_IRQF | RTC_AF);
+ return IRQ_HANDLED;
+}
+
+static struct rtc_class_ops palmas_rtc_ops = {
+ .read_time = palmas_rtc_read_time,
+ .set_time = palmas_rtc_set_time,
+ .read_alarm = palmas_rtc_read_alarm,
+ .set_alarm = palmas_rtc_set_alarm,
+ .alarm_irq_enable = palmas_rtc_alarm_irq_enable,
+};
+
+static int palmas_rtc_probe(struct platform_device *pdev)
+{
+ struct palmas *palmas = dev_get_drvdata(pdev->dev.parent);
+ struct palmas_rtc *palmas_rtc = NULL;
+ int ret;
+ bool enable_bb_charging = false;
+ bool high_bb_charging;
+
+ if (pdev->dev.of_node) {
+ enable_bb_charging = of_property_read_bool(pdev->dev.of_node,
+ "ti,backup-battery-chargeable");
+ high_bb_charging = of_property_read_bool(pdev->dev.of_node,
+ "ti,backup-battery-charge-high-current");
+ }
+
+ palmas_rtc = devm_kzalloc(&pdev->dev, sizeof(struct palmas_rtc),
+ GFP_KERNEL);
+ if (!palmas_rtc)
+ return -ENOMEM;
+
+ /* Clear pending interrupts */
+ ret = palmas_clear_interrupts(&pdev->dev);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "clear RTC int failed, err = %d\n", ret);
+ return ret;
+ }
+
+ palmas_rtc->dev = &pdev->dev;
+ platform_set_drvdata(pdev, palmas_rtc);
+
+ if (enable_bb_charging) {
+ unsigned reg = PALMAS_BACKUP_BATTERY_CTRL_BBS_BBC_LOW_ICHRG;
+
+ if (high_bb_charging)
+ reg = 0;
+
+ ret = palmas_update_bits(palmas, PALMAS_PMU_CONTROL_BASE,
+ PALMAS_BACKUP_BATTERY_CTRL,
+ PALMAS_BACKUP_BATTERY_CTRL_BBS_BBC_LOW_ICHRG, reg);
+ if (ret < 0) {
+ dev_err(&pdev->dev,
+ "BACKUP_BATTERY_CTRL update failed, %d\n", ret);
+ return ret;
+ }
+
+ ret = palmas_update_bits(palmas, PALMAS_PMU_CONTROL_BASE,
+ PALMAS_BACKUP_BATTERY_CTRL,
+ PALMAS_BACKUP_BATTERY_CTRL_BB_CHG_EN,
+ PALMAS_BACKUP_BATTERY_CTRL_BB_CHG_EN);
+ if (ret < 0) {
+ dev_err(&pdev->dev,
+ "BACKUP_BATTERY_CTRL update failed, %d\n", ret);
+ return ret;
+ }
+ }
+
+ /* Start RTC */
+ ret = palmas_update_bits(palmas, PALMAS_RTC_BASE, PALMAS_RTC_CTRL_REG,
+ PALMAS_RTC_CTRL_REG_STOP_RTC,
+ PALMAS_RTC_CTRL_REG_STOP_RTC);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "RTC_CTRL write failed, err = %d\n", ret);
+ return ret;
+ }
+
+ palmas_rtc->irq = platform_get_irq(pdev, 0);
+
+ device_init_wakeup(&pdev->dev, 1);
+ palmas_rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
+ &palmas_rtc_ops, THIS_MODULE);
+ if (IS_ERR(palmas_rtc->rtc)) {
+ ret = PTR_ERR(palmas_rtc->rtc);
+ dev_err(&pdev->dev, "RTC register failed, err = %d\n", ret);
+ return ret;
+ }
+
+ ret = devm_request_threaded_irq(&pdev->dev, palmas_rtc->irq, NULL,
+ palmas_rtc_interrupt,
+ IRQF_TRIGGER_LOW | IRQF_ONESHOT |
+ IRQF_EARLY_RESUME,
+ dev_name(&pdev->dev), palmas_rtc);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "IRQ request failed, err = %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int palmas_rtc_remove(struct platform_device *pdev)
+{
+ palmas_rtc_alarm_irq_enable(&pdev->dev, 0);
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int palmas_rtc_suspend(struct device *dev)
+{
+ struct palmas_rtc *palmas_rtc = dev_get_drvdata(dev);
+
+ if (device_may_wakeup(dev))
+ enable_irq_wake(palmas_rtc->irq);
+ return 0;
+}
+
+static int palmas_rtc_resume(struct device *dev)
+{
+ struct palmas_rtc *palmas_rtc = dev_get_drvdata(dev);
+
+ if (device_may_wakeup(dev))
+ disable_irq_wake(palmas_rtc->irq);
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(palmas_rtc_pm_ops, palmas_rtc_suspend,
+ palmas_rtc_resume);
+
+#ifdef CONFIG_OF
+static const struct of_device_id of_palmas_rtc_match[] = {
+ { .compatible = "ti,palmas-rtc"},
+ { },
+};
+MODULE_DEVICE_TABLE(of, of_palmas_rtc_match);
+#endif
+
+static struct platform_driver palmas_rtc_driver = {
+ .probe = palmas_rtc_probe,
+ .remove = palmas_rtc_remove,
+ .driver = {
+ .name = "palmas-rtc",
+ .pm = &palmas_rtc_pm_ops,
+ .of_match_table = of_match_ptr(of_palmas_rtc_match),
+ },
+};
+
+module_platform_driver(palmas_rtc_driver);
+
+MODULE_ALIAS("platform:palmas_rtc");
+MODULE_DESCRIPTION("TI PALMAS series RTC driver");
+MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
+MODULE_LICENSE("GPL v2");
Code Review / kvmfornfv.git / blobdiff