rtc: brcmstb-waketimer: Add Broadcom STB wake-timer (c4f07ece) · Commits · 戴 / test

drivers/rtc/Kconfig

+11 −0

Original line number	Diff line number	Diff line
		@@ -197,6 +197,17 @@ config RTC_DRV_AC100
		This driver can also be built as a module. If so, the module
		will be called rtc-ac100.

		config RTC_DRV_BRCMSTB
		tristate "Broadcom STB wake-timer"
		depends on ARCH_BRCMSTB \|\| BMIPS_GENERIC \|\| COMPILE_TEST
		default ARCH_BRCMSTB \|\| BMIPS_GENERIC
		help
		If you say yes here you get support for the wake-timer found on
		Broadcom STB SoCs (BCM7xxx).

		This driver can also be built as a module. If so, the module will
		be called rtc-brcmstb-waketimer.

		config RTC_DRV_AS3722
		tristate "ams AS3722 RTC driver"
		depends on MFD_AS3722

drivers/rtc/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -36,6 +36,7 @@ obj-$(CONFIG_RTC_DRV_AT91RM9200)+= rtc-at91rm9200.o
		obj-$(CONFIG_RTC_DRV_AT91SAM9) += rtc-at91sam9.o
		obj-$(CONFIG_RTC_DRV_AU1XXX) += rtc-au1xxx.o
		obj-$(CONFIG_RTC_DRV_BFIN) += rtc-bfin.o
		obj-$(CONFIG_RTC_DRV_BRCMSTB) += rtc-brcmstb-waketimer.o
		obj-$(CONFIG_RTC_DRV_BQ32K) += rtc-bq32k.o
		obj-$(CONFIG_RTC_DRV_BQ4802) += rtc-bq4802.o
		obj-$(CONFIG_RTC_DRV_CMOS) += rtc-cmos.o

drivers/rtc/rtc-brcmstb-waketimer.c

0 → 100644

+330 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright © 2014-2017 Broadcom
		*
		* 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.
		*
		* This program is distributed in the hope that it will be useful,
		* but WITHOUT ANY WARRANTY; without even the implied warranty of
		* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
		* GNU General Public License for more details.
		*/

		#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

		#include <linux/clk.h>
		#include <linux/device.h>
		#include <linux/err.h>
		#include <linux/init.h>
		#include <linux/interrupt.h>
		#include <linux/io.h>
		#include <linux/irqreturn.h>
		#include <linux/kernel.h>
		#include <linux/module.h>
		#include <linux/of.h>
		#include <linux/platform_device.h>
		#include <linux/pm.h>
		#include <linux/pm_wakeup.h>
		#include <linux/reboot.h>
		#include <linux/rtc.h>
		#include <linux/stat.h>
		#include <linux/suspend.h>

		struct brcmstb_waketmr {
		struct rtc_device *rtc;
		struct device *dev;
		void __iomem *base;
		int irq;
		struct notifier_block reboot_notifier;
		struct clk *clk;
		u32 rate;
		};

		#define BRCMSTB_WKTMR_EVENT 0x00
		#define BRCMSTB_WKTMR_COUNTER 0x04
		#define BRCMSTB_WKTMR_ALARM 0x08
		#define BRCMSTB_WKTMR_PRESCALER 0x0C
		#define BRCMSTB_WKTMR_PRESCALER_VAL 0x10

		#define BRCMSTB_WKTMR_DEFAULT_FREQ 27000000

		static inline void brcmstb_waketmr_clear_alarm(struct brcmstb_waketmr *timer)
		{
		writel_relaxed(1, timer->base + BRCMSTB_WKTMR_EVENT);
		(void)readl_relaxed(timer->base + BRCMSTB_WKTMR_EVENT);
		}

		static void brcmstb_waketmr_set_alarm(struct brcmstb_waketmr *timer,
		unsigned int secs)
		{
		brcmstb_waketmr_clear_alarm(timer);

		writel_relaxed(secs + 1, timer->base + BRCMSTB_WKTMR_ALARM);
		}

		static irqreturn_t brcmstb_waketmr_irq(int irq, void *data)
		{
		struct brcmstb_waketmr *timer = data;

		pm_wakeup_event(timer->dev, 0);

		return IRQ_HANDLED;
		}

		struct wktmr_time {
		u32 sec;
		u32 pre;
		};

		static void wktmr_read(struct brcmstb_waketmr *timer,
		struct wktmr_time *t)
		{
		u32 tmp;

		do {
		t->sec = readl_relaxed(timer->base + BRCMSTB_WKTMR_COUNTER);
		tmp = readl_relaxed(timer->base + BRCMSTB_WKTMR_PRESCALER_VAL);
		} while (tmp >= timer->rate);

		t->pre = timer->rate - tmp;
		}

		static int brcmstb_waketmr_prepare_suspend(struct brcmstb_waketmr *timer)
		{
		struct device *dev = timer->dev;
		int ret = 0;

		if (device_may_wakeup(dev)) {
		ret = enable_irq_wake(timer->irq);
		if (ret) {
		dev_err(dev, "failed to enable wake-up interrupt\n");
		return ret;
		}
		}

		return ret;
		}

		/* If enabled as a wakeup-source, arm the timer when powering off */
		static int brcmstb_waketmr_reboot(struct notifier_block *nb,
		unsigned long action, void *data)
		{
		struct brcmstb_waketmr *timer;

		timer = container_of(nb, struct brcmstb_waketmr, reboot_notifier);

		/* Set timer for cold boot */
		if (action == SYS_POWER_OFF)
		brcmstb_waketmr_prepare_suspend(timer);

		return NOTIFY_DONE;
		}

		static int brcmstb_waketmr_gettime(struct device *dev,
		struct rtc_time *tm)
		{
		struct brcmstb_waketmr *timer = dev_get_drvdata(dev);
		struct wktmr_time now;

		wktmr_read(timer, &now);

		rtc_time_to_tm(now.sec, tm);

		return 0;
		}

		static int brcmstb_waketmr_settime(struct device *dev,
		struct rtc_time *tm)
		{
		struct brcmstb_waketmr *timer = dev_get_drvdata(dev);
		time64_t sec;

		sec = rtc_tm_to_time64(tm);

		if (sec > U32_MAX \|\| sec < 0)
		return -EINVAL;

		writel_relaxed(sec, timer->base + BRCMSTB_WKTMR_COUNTER);

		return 0;
		}

		static int brcmstb_waketmr_getalarm(struct device *dev,
		struct rtc_wkalrm *alarm)
		{
		struct brcmstb_waketmr *timer = dev_get_drvdata(dev);
		time64_t sec;
		u32 reg;

		sec = readl_relaxed(timer->base + BRCMSTB_WKTMR_ALARM);
		if (sec != 0) {
		/* Alarm is enabled */
		alarm->enabled = 1;
		rtc_time64_to_tm(sec, &alarm->time);
		}

		reg = readl_relaxed(timer->base + BRCMSTB_WKTMR_EVENT);
		alarm->pending = !!(reg & 1);

		return 0;
		}

		static int brcmstb_waketmr_setalarm(struct device *dev,
		struct rtc_wkalrm *alarm)
		{
		struct brcmstb_waketmr *timer = dev_get_drvdata(dev);
		time64_t sec;

		if (alarm->enabled)
		sec = rtc_tm_to_time64(&alarm->time);
		else
		sec = 0;

		if (sec > U32_MAX \|\| sec < 0)
		return -EINVAL;

		brcmstb_waketmr_set_alarm(timer, sec);

		return 0;
		}

		/*
		* Does not do much but keep the RTC class happy. We always support
		* alarms.
		*/
		static int brcmstb_waketmr_alarm_enable(struct device *dev,
		unsigned int enabled)
		{
		return 0;
		}

		static const struct rtc_class_ops brcmstb_waketmr_ops = {
		.read_time = brcmstb_waketmr_gettime,
		.set_time = brcmstb_waketmr_settime,
		.read_alarm = brcmstb_waketmr_getalarm,
		.set_alarm = brcmstb_waketmr_setalarm,
		.alarm_irq_enable = brcmstb_waketmr_alarm_enable,
		};

		static int brcmstb_waketmr_probe(struct platform_device *pdev)
		{
		struct device *dev = &pdev->dev;
		struct brcmstb_waketmr *timer;
		struct resource *res;
		int ret;

		timer = devm_kzalloc(dev, sizeof(*timer), GFP_KERNEL);
		if (!timer)
		return -ENOMEM;

		platform_set_drvdata(pdev, timer);
		timer->dev = dev;

		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
		timer->base = devm_ioremap_resource(dev, res);
		if (IS_ERR(timer->base))
		return PTR_ERR(timer->base);

		/*
		* Set wakeup capability before requesting wakeup interrupt, so we can
		* process boot-time "wakeups" (e.g., from S5 soft-off)
		*/
		device_set_wakeup_capable(dev, true);
		device_wakeup_enable(dev);

		timer->irq = platform_get_irq(pdev, 0);
		if (timer->irq < 0)
		return -ENODEV;

		timer->clk = devm_clk_get(dev, NULL);
		if (!IS_ERR(timer->clk)) {
		ret = clk_prepare_enable(timer->clk);
		if (ret)
		return ret;
		timer->rate = clk_get_rate(timer->clk);
		if (!timer->rate)
		timer->rate = BRCMSTB_WKTMR_DEFAULT_FREQ;
		} else {
		timer->rate = BRCMSTB_WKTMR_DEFAULT_FREQ;
		timer->clk = NULL;
		}

		ret = devm_request_irq(dev, timer->irq, brcmstb_waketmr_irq, 0,
		"brcmstb-waketimer", timer);
		if (ret < 0)
		return ret;

		timer->reboot_notifier.notifier_call = brcmstb_waketmr_reboot;
		register_reboot_notifier(&timer->reboot_notifier);

		timer->rtc = rtc_device_register("brcmstb-waketmr", dev,
		&brcmstb_waketmr_ops, THIS_MODULE);
		if (IS_ERR(timer->rtc)) {
		dev_err(dev, "unable to register device\n");
		unregister_reboot_notifier(&timer->reboot_notifier);
		return PTR_ERR(timer->rtc);
		}

		dev_info(dev, "registered, with irq %d\n", timer->irq);

		return ret;
		}

		static int brcmstb_waketmr_remove(struct platform_device *pdev)
		{
		struct brcmstb_waketmr *timer = dev_get_drvdata(&pdev->dev);

		unregister_reboot_notifier(&timer->reboot_notifier);
		rtc_device_unregister(timer->rtc);

		return 0;
		}

		#ifdef CONFIG_PM_SLEEP
		static int brcmstb_waketmr_suspend(struct device *dev)
		{
		struct brcmstb_waketmr *timer = dev_get_drvdata(dev);

		return brcmstb_waketmr_prepare_suspend(timer);
		}

		static int brcmstb_waketmr_resume(struct device *dev)
		{
		struct brcmstb_waketmr *timer = dev_get_drvdata(dev);
		int ret;

		if (!device_may_wakeup(dev))
		return 0;

		ret = disable_irq_wake(timer->irq);

		brcmstb_waketmr_clear_alarm(timer);

		return ret;
		}
		#endif /* CONFIG_PM_SLEEP */

		static SIMPLE_DEV_PM_OPS(brcmstb_waketmr_pm_ops,
		brcmstb_waketmr_suspend, brcmstb_waketmr_resume);

		static const struct of_device_id brcmstb_waketmr_of_match[] = {
		{ .compatible = "brcm,brcmstb-waketimer" },
		{ /* sentinel */ },
		};

		static struct platform_driver brcmstb_waketmr_driver = {
		.probe = brcmstb_waketmr_probe,
		.remove = brcmstb_waketmr_remove,
		.driver = {
		.name = "brcmstb-waketimer",
		.pm = &brcmstb_waketmr_pm_ops,
		.of_match_table = of_match_ptr(brcmstb_waketmr_of_match),
		}
		};
		module_platform_driver(brcmstb_waketmr_driver);

		MODULE_LICENSE("GPL v2");
		MODULE_AUTHOR("Brian Norris");
		MODULE_AUTHOR("Markus Mayer");
		MODULE_DESCRIPTION("Wake-up timer driver for STB chips");

Admin message