+++ /dev/null
-/*
- * An RTC driver for the AVR32 AT32AP700x processor series.
- *
- * Copyright (C) 2007 Atmel Corporation
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 as published
- * by the Free Software Foundation.
- */
-
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/platform_device.h>
-#include <linux/slab.h>
-#include <linux/rtc.h>
-#include <linux/io.h>
-
-/*
- * This is a bare-bones RTC. It runs during most system sleep states, but has
- * no battery backup and gets reset during system restart. It must be
- * initialized from an external clock (network, I2C, etc) before it can be of
- * much use.
- *
- * The alarm functionality is limited by the hardware, not supporting
- * periodic interrupts.
- */
-
-#define RTC_CTRL 0x00
-#define RTC_CTRL_EN 0
-#define RTC_CTRL_PCLR 1
-#define RTC_CTRL_TOPEN 2
-#define RTC_CTRL_PSEL 8
-
-#define RTC_VAL 0x04
-
-#define RTC_TOP 0x08
-
-#define RTC_IER 0x10
-#define RTC_IER_TOPI 0
-
-#define RTC_IDR 0x14
-#define RTC_IDR_TOPI 0
-
-#define RTC_IMR 0x18
-#define RTC_IMR_TOPI 0
-
-#define RTC_ISR 0x1c
-#define RTC_ISR_TOPI 0
-
-#define RTC_ICR 0x20
-#define RTC_ICR_TOPI 0
-
-#define RTC_BIT(name) (1 << RTC_##name)
-#define RTC_BF(name, value) ((value) << RTC_##name)
-
-#define rtc_readl(dev, reg) \
- __raw_readl((dev)->regs + RTC_##reg)
-#define rtc_writel(dev, reg, value) \
- __raw_writel((value), (dev)->regs + RTC_##reg)
-
-struct rtc_at32ap700x {
- struct rtc_device *rtc;
- void __iomem *regs;
- unsigned long alarm_time;
- unsigned long irq;
- /* Protect against concurrent register access. */
- spinlock_t lock;
-};
-
-static int at32_rtc_readtime(struct device *dev, struct rtc_time *tm)
-{
- struct rtc_at32ap700x *rtc = dev_get_drvdata(dev);
- unsigned long now;
-
- now = rtc_readl(rtc, VAL);
- rtc_time_to_tm(now, tm);
-
- return 0;
-}
-
-static int at32_rtc_settime(struct device *dev, struct rtc_time *tm)
-{
- struct rtc_at32ap700x *rtc = dev_get_drvdata(dev);
- unsigned long now;
- int ret;
-
- ret = rtc_tm_to_time(tm, &now);
- if (ret == 0)
- rtc_writel(rtc, VAL, now);
-
- return ret;
-}
-
-static int at32_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
-{
- struct rtc_at32ap700x *rtc = dev_get_drvdata(dev);
-
- spin_lock_irq(&rtc->lock);
- rtc_time_to_tm(rtc->alarm_time, &alrm->time);
- alrm->enabled = rtc_readl(rtc, IMR) & RTC_BIT(IMR_TOPI) ? 1 : 0;
- alrm->pending = rtc_readl(rtc, ISR) & RTC_BIT(ISR_TOPI) ? 1 : 0;
- spin_unlock_irq(&rtc->lock);
-
- return 0;
-}
-
-static int at32_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
-{
- struct rtc_at32ap700x *rtc = dev_get_drvdata(dev);
- unsigned long rtc_unix_time;
- unsigned long alarm_unix_time;
- int ret;
-
- rtc_unix_time = rtc_readl(rtc, VAL);
-
- ret = rtc_tm_to_time(&alrm->time, &alarm_unix_time);
- if (ret)
- return ret;
-
- if (alarm_unix_time < rtc_unix_time)
- return -EINVAL;
-
- spin_lock_irq(&rtc->lock);
- rtc->alarm_time = alarm_unix_time;
- rtc_writel(rtc, TOP, rtc->alarm_time);
- if (alrm->enabled)
- rtc_writel(rtc, CTRL, rtc_readl(rtc, CTRL)
- | RTC_BIT(CTRL_TOPEN));
- else
- rtc_writel(rtc, CTRL, rtc_readl(rtc, CTRL)
- & ~RTC_BIT(CTRL_TOPEN));
- spin_unlock_irq(&rtc->lock);
-
- return ret;
-}
-
-static int at32_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
-{
- struct rtc_at32ap700x *rtc = dev_get_drvdata(dev);
- int ret = 0;
-
- spin_lock_irq(&rtc->lock);
-
- if (enabled) {
- if (rtc_readl(rtc, VAL) > rtc->alarm_time) {
- ret = -EINVAL;
- goto out;
- }
- rtc_writel(rtc, CTRL, rtc_readl(rtc, CTRL)
- | RTC_BIT(CTRL_TOPEN));
- rtc_writel(rtc, ICR, RTC_BIT(ICR_TOPI));
- rtc_writel(rtc, IER, RTC_BIT(IER_TOPI));
- } else {
- rtc_writel(rtc, CTRL, rtc_readl(rtc, CTRL)
- & ~RTC_BIT(CTRL_TOPEN));
- rtc_writel(rtc, IDR, RTC_BIT(IDR_TOPI));
- rtc_writel(rtc, ICR, RTC_BIT(ICR_TOPI));
- }
-out:
- spin_unlock_irq(&rtc->lock);
-
- return ret;
-}
-
-static irqreturn_t at32_rtc_interrupt(int irq, void *dev_id)
-{
- struct rtc_at32ap700x *rtc = (struct rtc_at32ap700x *)dev_id;
- unsigned long isr = rtc_readl(rtc, ISR);
- unsigned long events = 0;
- int ret = IRQ_NONE;
-
- spin_lock(&rtc->lock);
-
- if (isr & RTC_BIT(ISR_TOPI)) {
- rtc_writel(rtc, ICR, RTC_BIT(ICR_TOPI));
- rtc_writel(rtc, IDR, RTC_BIT(IDR_TOPI));
- rtc_writel(rtc, CTRL, rtc_readl(rtc, CTRL)
- & ~RTC_BIT(CTRL_TOPEN));
- rtc_writel(rtc, VAL, rtc->alarm_time);
- events = RTC_AF | RTC_IRQF;
- rtc_update_irq(rtc->rtc, 1, events);
- ret = IRQ_HANDLED;
- }
-
- spin_unlock(&rtc->lock);
-
- return ret;
-}
-
-static const struct rtc_class_ops at32_rtc_ops = {
- .read_time = at32_rtc_readtime,
- .set_time = at32_rtc_settime,
- .read_alarm = at32_rtc_readalarm,
- .set_alarm = at32_rtc_setalarm,
- .alarm_irq_enable = at32_rtc_alarm_irq_enable,
-};
-
-static int __init at32_rtc_probe(struct platform_device *pdev)
-{
- struct resource *regs;
- struct rtc_at32ap700x *rtc;
- int irq;
- int ret;
-
- rtc = devm_kzalloc(&pdev->dev, sizeof(struct rtc_at32ap700x),
- GFP_KERNEL);
- if (!rtc)
- return -ENOMEM;
-
- regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (!regs) {
- dev_dbg(&pdev->dev, "no mmio resource defined\n");
- return -ENXIO;
- }
-
- irq = platform_get_irq(pdev, 0);
- if (irq <= 0) {
- dev_dbg(&pdev->dev, "could not get irq\n");
- return -ENXIO;
- }
-
- rtc->irq = irq;
- rtc->regs = devm_ioremap(&pdev->dev, regs->start, resource_size(regs));
- if (!rtc->regs) {
- dev_dbg(&pdev->dev, "could not map I/O memory\n");
- return -ENOMEM;
- }
- spin_lock_init(&rtc->lock);
-
- /*
- * Maybe init RTC: count from zero at 1 Hz, disable wrap irq.
- *
- * Do not reset VAL register, as it can hold an old time
- * from last JTAG reset.
- */
- if (!(rtc_readl(rtc, CTRL) & RTC_BIT(CTRL_EN))) {
- rtc_writel(rtc, CTRL, RTC_BIT(CTRL_PCLR));
- rtc_writel(rtc, IDR, RTC_BIT(IDR_TOPI));
- rtc_writel(rtc, CTRL, RTC_BF(CTRL_PSEL, 0xe)
- | RTC_BIT(CTRL_EN));
- }
-
- ret = devm_request_irq(&pdev->dev, irq, at32_rtc_interrupt, IRQF_SHARED,
- "rtc", rtc);
- if (ret) {
- dev_dbg(&pdev->dev, "could not request irq %d\n", irq);
- return ret;
- }
-
- platform_set_drvdata(pdev, rtc);
-
- rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
- &at32_rtc_ops, THIS_MODULE);
- if (IS_ERR(rtc->rtc)) {
- dev_dbg(&pdev->dev, "could not register rtc device\n");
- return PTR_ERR(rtc->rtc);
- }
-
- device_init_wakeup(&pdev->dev, 1);
-
- dev_info(&pdev->dev, "Atmel RTC for AT32AP700x at %08lx irq %ld\n",
- (unsigned long)rtc->regs, rtc->irq);
-
- return 0;
-}
-
-static int __exit at32_rtc_remove(struct platform_device *pdev)
-{
- device_init_wakeup(&pdev->dev, 0);
-
- return 0;
-}
-
-MODULE_ALIAS("platform:at32ap700x_rtc");
-
-static struct platform_driver at32_rtc_driver = {
- .remove = __exit_p(at32_rtc_remove),
- .driver = {
- .name = "at32ap700x_rtc",
- },
-};
-
-module_platform_driver_probe(at32_rtc_driver, at32_rtc_probe);
-
-MODULE_AUTHOR("Hans-Christian Egtvedt <egtvedt@samfundet.no>");
-MODULE_DESCRIPTION("Real time clock for AVR32 AT32AP700x");
-MODULE_LICENSE("GPL");
projects / platform / kernel / linux-rpi.git / commitdiff