rtc: AB3100 RTC support (bd207cfb) · Commits · 戴 / test

drivers/rtc/Kconfig

+9 −0

Original line number	Diff line number	Diff line
		@@ -545,6 +545,15 @@ config RTC_DRV_PCF50633
		If you say yes here you get support for the RTC subsystem of the
		NXP PCF50633 used in embedded systems.

		config RTC_DRV_AB3100
		tristate "ST-Ericsson AB3100 RTC"
		depends on AB3100_CORE
		default y if AB3100_CORE
		help
		Select this to enable the ST-Ericsson AB3100 Mixed Signal IC RTC
		support. This chip contains a battery- and capacitor-backed RTC.


		comment "on-CPU RTC drivers"

		config RTC_DRV_OMAP

drivers/rtc/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -17,6 +17,7 @@ rtc-core-$(CONFIG_RTC_INTF_SYSFS) += rtc-sysfs.o

		# Keep the list ordered.

		obj-$(CONFIG_RTC_DRV_AB3100) += rtc-ab3100.o
		obj-$(CONFIG_RTC_DRV_AT32AP700X)+= rtc-at32ap700x.o
		obj-$(CONFIG_RTC_DRV_AT91RM9200)+= rtc-at91rm9200.o
		obj-$(CONFIG_RTC_DRV_AT91SAM9) += rtc-at91sam9.o

drivers/rtc/rtc-ab3100.c

0 → 100644

+281 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2007-2009 ST-Ericsson AB
		* License terms: GNU General Public License (GPL) version 2
		* RTC clock driver for the AB3100 Analog Baseband Chip
		* Author: Linus Walleij <linus.walleij@stericsson.com>
		*/
		#include <linux/module.h>
		#include <linux/kernel.h>
		#include <linux/init.h>
		#include <linux/platform_device.h>
		#include <linux/rtc.h>
		#include <linux/mfd/ab3100.h>

		/* Clock rate in Hz */
		#define AB3100_RTC_CLOCK_RATE 32768

		/*
		* The AB3100 RTC registers. These are the same for
		* AB3000 and AB3100.
		* Control register:
		* Bit 0: RTC Monitor cleared=0, active=1, if you set it
		* to 1 it remains active until RTC power is lost.
		* Bit 1: 32 kHz Oscillator, 0 = on, 1 = bypass
		* Bit 2: Alarm on, 0 = off, 1 = on
		* Bit 3: 32 kHz buffer disabling, 0 = enabled, 1 = disabled
		*/
		#define AB3100_RTC 0x53
		/* default setting, buffer disabled, alarm on */
		#define RTC_SETTING 0x30
		/* Alarm when AL0-AL3 == TI0-TI3 */
		#define AB3100_AL0 0x56
		#define AB3100_AL1 0x57
		#define AB3100_AL2 0x58
		#define AB3100_AL3 0x59
		/* This 48-bit register that counts up at 32768 Hz */
		#define AB3100_TI0 0x5a
		#define AB3100_TI1 0x5b
		#define AB3100_TI2 0x5c
		#define AB3100_TI3 0x5d
		#define AB3100_TI4 0x5e
		#define AB3100_TI5 0x5f

		/*
		* RTC clock functions and device struct declaration
		*/
		static int ab3100_rtc_set_mmss(struct device *dev, unsigned long secs)
		{
		struct ab3100 *ab3100_data = dev_get_drvdata(dev);
		u8 regs[] = {AB3100_TI0, AB3100_TI1, AB3100_TI2,
		AB3100_TI3, AB3100_TI4, AB3100_TI5};
		unsigned char buf[6];
		u64 fat_time = (u64) secs * AB3100_RTC_CLOCK_RATE * 2;
		int err = 0;
		int i;

		buf[0] = (fat_time) & 0xFF;
		buf[1] = (fat_time >> 8) & 0xFF;
		buf[2] = (fat_time >> 16) & 0xFF;
		buf[3] = (fat_time >> 24) & 0xFF;
		buf[4] = (fat_time >> 32) & 0xFF;
		buf[5] = (fat_time >> 40) & 0xFF;

		for (i = 0; i < 6; i++) {
		err = ab3100_set_register_interruptible(ab3100_data,
		regs[i], buf[i]);
		if (err)
		return err;
		}

		/* Set the flag to mark that the clock is now set */
		return ab3100_mask_and_set_register_interruptible(ab3100_data,
		AB3100_RTC,
		0xFE, 0x01);

		}

		static int ab3100_rtc_read_time(struct device dev, struct rtc_time tm)
		{
		struct ab3100 *ab3100_data = dev_get_drvdata(dev);
		unsigned long time;
		u8 rtcval;
		int err;

		err = ab3100_get_register_interruptible(ab3100_data,
		AB3100_RTC, &rtcval);
		if (err)
		return err;

		if (!(rtcval & 0x01)) {
		dev_info(dev, "clock not set (lost power)");
		return -EINVAL;
		} else {
		u64 fat_time;
		u8 buf[6];

		/* Read out time registers */
		err = ab3100_get_register_page_interruptible(ab3100_data,
		AB3100_TI0,
		buf, 6);
		if (err != 0)
		return err;

		fat_time = ((u64) buf[5] << 40) \| ((u64) buf[4] << 32) \|
		((u64) buf[3] << 24) \| ((u64) buf[2] << 16) \|
		((u64) buf[1] << 8) \| (u64) buf[0];
		time = (unsigned long) (fat_time /
		(u64) (AB3100_RTC_CLOCK_RATE * 2));
		}

		rtc_time_to_tm(time, tm);

		return rtc_valid_tm(tm);
		}

		static int ab3100_rtc_read_alarm(struct device dev, struct rtc_wkalrm alarm)
		{
		struct ab3100 *ab3100_data = dev_get_drvdata(dev);
		unsigned long time;
		u64 fat_time;
		u8 buf[6];
		u8 rtcval;
		int err;

		/* Figure out if alarm is enabled or not */
		err = ab3100_get_register_interruptible(ab3100_data,
		AB3100_RTC, &rtcval);
		if (err)
		return err;
		if (rtcval & 0x04)
		alarm->enabled = 1;
		else
		alarm->enabled = 0;
		/* No idea how this could be represented */
		alarm->pending = 0;
		/* Read out alarm registers, only 4 bytes */
		err = ab3100_get_register_page_interruptible(ab3100_data,
		AB3100_AL0, buf, 4);
		if (err)
		return err;
		fat_time = ((u64) buf[3] << 40) \| ((u64) buf[2] << 32) \|
		((u64) buf[1] << 24) \| ((u64) buf[0] << 16);
		time = (unsigned long) (fat_time / (u64) (AB3100_RTC_CLOCK_RATE * 2));

		rtc_time_to_tm(time, &alarm->time);

		return rtc_valid_tm(&alarm->time);
		}

		static int ab3100_rtc_set_alarm(struct device dev, struct rtc_wkalrm alarm)
		{
		struct ab3100 *ab3100_data = dev_get_drvdata(dev);
		u8 regs[] = {AB3100_AL0, AB3100_AL1, AB3100_AL2, AB3100_AL3};
		unsigned char buf[4];
		unsigned long secs;
		u64 fat_time;
		int err;
		int i;

		rtc_tm_to_time(&alarm->time, &secs);
		fat_time = (u64) secs * AB3100_RTC_CLOCK_RATE * 2;
		buf[0] = (fat_time >> 16) & 0xFF;
		buf[1] = (fat_time >> 24) & 0xFF;
		buf[2] = (fat_time >> 32) & 0xFF;
		buf[3] = (fat_time >> 40) & 0xFF;

		/* Set the alarm */
		for (i = 0; i < 4; i++) {
		err = ab3100_set_register_interruptible(ab3100_data,
		regs[i], buf[i]);
		if (err)
		return err;
		}
		/* Then enable the alarm */
		return ab3100_mask_and_set_register_interruptible(ab3100_data,
		AB3100_RTC, ~(1 << 2),
		alarm->enabled << 2);
		}

		static int ab3100_rtc_irq_enable(struct device *dev, unsigned int enabled)
		{
		struct ab3100 *ab3100_data = dev_get_drvdata(dev);

		/*
		* It's not possible to enable/disable the alarm IRQ for this RTC.
		* It does not actually trigger any IRQ: instead its only function is
		* to power up the system, if it wasn't on. This will manifest as
		* a "power up cause" in the AB3100 power driver (battery charging etc)
		* and need to be handled there instead.
		*/
		if (enabled)
		return ab3100_mask_and_set_register_interruptible(ab3100_data,
		AB3100_RTC, ~(1 << 2),
		1 << 2);
		else
		return ab3100_mask_and_set_register_interruptible(ab3100_data,
		AB3100_RTC, ~(1 << 2),
		0);
		}

		static const struct rtc_class_ops ab3100_rtc_ops = {
		.read_time = ab3100_rtc_read_time,
		.set_mmss = ab3100_rtc_set_mmss,
		.read_alarm = ab3100_rtc_read_alarm,
		.set_alarm = ab3100_rtc_set_alarm,
		.alarm_irq_enable = ab3100_rtc_irq_enable,
		};

		static int __init ab3100_rtc_probe(struct platform_device *pdev)
		{
		int err;
		u8 regval;
		struct rtc_device *rtc;
		struct ab3100 *ab3100_data = platform_get_drvdata(pdev);

		/* The first RTC register needs special treatment */
		err = ab3100_get_register_interruptible(ab3100_data,
		AB3100_RTC, &regval);
		if (err) {
		dev_err(&pdev->dev, "unable to read RTC register\n");
		return -ENODEV;
		}

		if ((regval & 0xFE) != RTC_SETTING) {
		dev_warn(&pdev->dev, "not default value in RTC reg 0x%x\n",
		regval);
		}

		if ((regval & 1) == 0) {
		/*
		* Set bit to detect power loss.
		* This bit remains until RTC power is lost.
		*/
		regval = 1 \| RTC_SETTING;
		err = ab3100_set_register_interruptible(ab3100_data,
		AB3100_RTC, regval);
		/* Ignore any error on this write */
		}

		rtc = rtc_device_register("ab3100-rtc", &pdev->dev, &ab3100_rtc_ops,
		THIS_MODULE);
		if (IS_ERR(rtc)) {
		err = PTR_ERR(rtc);
		return err;
		}

		return 0;
		}

		static int __exit ab3100_rtc_remove(struct platform_device *pdev)
		{
		struct rtc_device *rtc = platform_get_drvdata(pdev);

		rtc_device_unregister(rtc);
		return 0;
		}

		static struct platform_driver ab3100_rtc_driver = {
		.driver = {
		.name = "ab3100-rtc",
		.owner = THIS_MODULE,
		},
		.remove = __exit_p(ab3100_rtc_remove),
		};

		static int __init ab3100_rtc_init(void)
		{
		return platform_driver_probe(&ab3100_rtc_driver,
		ab3100_rtc_probe);
		}

		static void __exit ab3100_rtc_exit(void)
		{
		platform_driver_unregister(&ab3100_rtc_driver);
		}

		module_init(ab3100_rtc_init);
		module_exit(ab3100_rtc_exit);

		MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>");
		MODULE_DESCRIPTION("AB3100 RTC Driver");
		MODULE_LICENSE("GPL");

Admin message