+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright (C) 2007-2009 ST-Ericsson AB
- * Real Time Clock interface for ST-Ericsson AB COH 901 331 RTC.
- * Author: Linus Walleij <linus.walleij@stericsson.com>
- * Based on rtc-pl031.c by Deepak Saxena <dsaxena@plexity.net>
- * Copyright 2006 (c) MontaVista Software, Inc.
- */
-#include <linux/init.h>
-#include <linux/module.h>
-#include <linux/mod_devicetable.h>
-#include <linux/rtc.h>
-#include <linux/clk.h>
-#include <linux/interrupt.h>
-#include <linux/pm.h>
-#include <linux/platform_device.h>
-#include <linux/io.h>
-#include <linux/slab.h>
-
-/*
- * Registers in the COH 901 331
- */
-/* Alarm value 32bit (R/W) */
-#define COH901331_ALARM 0x00U
-/* Used to set current time 32bit (R/W) */
-#define COH901331_SET_TIME 0x04U
-/* Indication if current time is valid 32bit (R/-) */
-#define COH901331_VALID 0x08U
-/* Read the current time 32bit (R/-) */
-#define COH901331_CUR_TIME 0x0cU
-/* Event register for the "alarm" interrupt */
-#define COH901331_IRQ_EVENT 0x10U
-/* Mask register for the "alarm" interrupt */
-#define COH901331_IRQ_MASK 0x14U
-/* Force register for the "alarm" interrupt */
-#define COH901331_IRQ_FORCE 0x18U
-
-/*
- * Reference to RTC block clock
- * Notice that the frequent clk_enable()/clk_disable() on this
- * clock is mainly to be able to turn on/off other clocks in the
- * hierarchy as needed, the RTC clock is always on anyway.
- */
-struct coh901331_port {
- struct rtc_device *rtc;
- struct clk *clk;
- void __iomem *virtbase;
- int irq;
-#ifdef CONFIG_PM_SLEEP
- u32 irqmaskstore;
-#endif
-};
-
-static irqreturn_t coh901331_interrupt(int irq, void *data)
-{
- struct coh901331_port *rtap = data;
-
- clk_enable(rtap->clk);
- /* Ack IRQ */
- writel(1, rtap->virtbase + COH901331_IRQ_EVENT);
- /*
- * Disable the interrupt. This is necessary because
- * the RTC lives on a lower-clocked line and will
- * not release the IRQ line until after a few (slower)
- * clock cycles. The interrupt will be re-enabled when
- * a new alarm is set anyway.
- */
- writel(0, rtap->virtbase + COH901331_IRQ_MASK);
- clk_disable(rtap->clk);
-
- /* Set alarm flag */
- rtc_update_irq(rtap->rtc, 1, RTC_AF);
-
- return IRQ_HANDLED;
-}
-
-static int coh901331_read_time(struct device *dev, struct rtc_time *tm)
-{
- struct coh901331_port *rtap = dev_get_drvdata(dev);
-
- clk_enable(rtap->clk);
- /* Check if the time is valid */
- if (!readl(rtap->virtbase + COH901331_VALID)) {
- clk_disable(rtap->clk);
- return -EINVAL;
- }
-
- rtc_time64_to_tm(readl(rtap->virtbase + COH901331_CUR_TIME), tm);
- clk_disable(rtap->clk);
- return 0;
-}
-
-static int coh901331_set_time(struct device *dev, struct rtc_time *tm)
-{
- struct coh901331_port *rtap = dev_get_drvdata(dev);
-
- clk_enable(rtap->clk);
- writel(rtc_tm_to_time64(tm), rtap->virtbase + COH901331_SET_TIME);
- clk_disable(rtap->clk);
-
- return 0;
-}
-
-static int coh901331_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
-{
- struct coh901331_port *rtap = dev_get_drvdata(dev);
-
- clk_enable(rtap->clk);
- rtc_time64_to_tm(readl(rtap->virtbase + COH901331_ALARM), &alarm->time);
- alarm->pending = readl(rtap->virtbase + COH901331_IRQ_EVENT) & 1U;
- alarm->enabled = readl(rtap->virtbase + COH901331_IRQ_MASK) & 1U;
- clk_disable(rtap->clk);
-
- return 0;
-}
-
-static int coh901331_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
-{
- struct coh901331_port *rtap = dev_get_drvdata(dev);
- unsigned long time = rtc_tm_to_time64(&alarm->time);
-
- clk_enable(rtap->clk);
- writel(time, rtap->virtbase + COH901331_ALARM);
- writel(alarm->enabled, rtap->virtbase + COH901331_IRQ_MASK);
- clk_disable(rtap->clk);
-
- return 0;
-}
-
-static int coh901331_alarm_irq_enable(struct device *dev, unsigned int enabled)
-{
- struct coh901331_port *rtap = dev_get_drvdata(dev);
-
- clk_enable(rtap->clk);
- if (enabled)
- writel(1, rtap->virtbase + COH901331_IRQ_MASK);
- else
- writel(0, rtap->virtbase + COH901331_IRQ_MASK);
- clk_disable(rtap->clk);
-
- return 0;
-}
-
-static const struct rtc_class_ops coh901331_ops = {
- .read_time = coh901331_read_time,
- .set_time = coh901331_set_time,
- .read_alarm = coh901331_read_alarm,
- .set_alarm = coh901331_set_alarm,
- .alarm_irq_enable = coh901331_alarm_irq_enable,
-};
-
-static int __exit coh901331_remove(struct platform_device *pdev)
-{
- struct coh901331_port *rtap = platform_get_drvdata(pdev);
-
- if (rtap)
- clk_unprepare(rtap->clk);
-
- return 0;
-}
-
-
-static int __init coh901331_probe(struct platform_device *pdev)
-{
- int ret;
- struct coh901331_port *rtap;
-
- rtap = devm_kzalloc(&pdev->dev,
- sizeof(struct coh901331_port), GFP_KERNEL);
- if (!rtap)
- return -ENOMEM;
-
- rtap->virtbase = devm_platform_ioremap_resource(pdev, 0);
- if (IS_ERR(rtap->virtbase))
- return PTR_ERR(rtap->virtbase);
-
- rtap->irq = platform_get_irq(pdev, 0);
- if (devm_request_irq(&pdev->dev, rtap->irq, coh901331_interrupt, 0,
- "RTC COH 901 331 Alarm", rtap))
- return -EIO;
-
- rtap->clk = devm_clk_get(&pdev->dev, NULL);
- if (IS_ERR(rtap->clk)) {
- ret = PTR_ERR(rtap->clk);
- dev_err(&pdev->dev, "could not get clock\n");
- return ret;
- }
-
- rtap->rtc = devm_rtc_allocate_device(&pdev->dev);
- if (IS_ERR(rtap->rtc))
- return PTR_ERR(rtap->rtc);
-
- rtap->rtc->ops = &coh901331_ops;
- rtap->rtc->range_max = U32_MAX;
-
- /* We enable/disable the clock only to assure it works */
- ret = clk_prepare_enable(rtap->clk);
- if (ret) {
- dev_err(&pdev->dev, "could not enable clock\n");
- return ret;
- }
- clk_disable(rtap->clk);
-
- platform_set_drvdata(pdev, rtap);
-
- ret = devm_rtc_register_device(rtap->rtc);
- if (ret)
- goto out_no_rtc;
-
- return 0;
-
- out_no_rtc:
- clk_unprepare(rtap->clk);
- return ret;
-}
-
-#ifdef CONFIG_PM_SLEEP
-static int coh901331_suspend(struct device *dev)
-{
- struct coh901331_port *rtap = dev_get_drvdata(dev);
-
- /*
- * If this RTC alarm will be used for waking the system up,
- * don't disable it of course. Else we just disable the alarm
- * and await suspension.
- */
- if (device_may_wakeup(dev)) {
- enable_irq_wake(rtap->irq);
- } else {
- clk_enable(rtap->clk);
- rtap->irqmaskstore = readl(rtap->virtbase + COH901331_IRQ_MASK);
- writel(0, rtap->virtbase + COH901331_IRQ_MASK);
- clk_disable(rtap->clk);
- }
- clk_unprepare(rtap->clk);
- return 0;
-}
-
-static int coh901331_resume(struct device *dev)
-{
- int ret;
- struct coh901331_port *rtap = dev_get_drvdata(dev);
-
- ret = clk_prepare(rtap->clk);
- if (ret)
- return ret;
-
- if (device_may_wakeup(dev)) {
- disable_irq_wake(rtap->irq);
- } else {
- clk_enable(rtap->clk);
- writel(rtap->irqmaskstore, rtap->virtbase + COH901331_IRQ_MASK);
- clk_disable(rtap->clk);
- }
- return 0;
-}
-#endif
-
-static SIMPLE_DEV_PM_OPS(coh901331_pm_ops, coh901331_suspend, coh901331_resume);
-
-static void coh901331_shutdown(struct platform_device *pdev)
-{
- struct coh901331_port *rtap = platform_get_drvdata(pdev);
-
- clk_enable(rtap->clk);
- writel(0, rtap->virtbase + COH901331_IRQ_MASK);
- clk_disable_unprepare(rtap->clk);
-}
-
-static const struct of_device_id coh901331_dt_match[] = {
- { .compatible = "stericsson,coh901331" },
- {},
-};
-MODULE_DEVICE_TABLE(of, coh901331_dt_match);
-
-static struct platform_driver coh901331_driver = {
- .driver = {
- .name = "rtc-coh901331",
- .pm = &coh901331_pm_ops,
- .of_match_table = coh901331_dt_match,
- },
- .remove = __exit_p(coh901331_remove),
- .shutdown = coh901331_shutdown,
-};
-
-module_platform_driver_probe(coh901331_driver, coh901331_probe);
-
-MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>");
-MODULE_DESCRIPTION("ST-Ericsson AB COH 901 331 RTC Driver");
-MODULE_LICENSE("GPL");
projects / linux-2.6-block.git / commitdiff