+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright (C) 2007-2009 ST-Ericsson AB
- * 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/abx500.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_time(struct device *dev, struct rtc_time *tm)
-{
- u8 regs[] = {AB3100_TI0, AB3100_TI1, AB3100_TI2,
- AB3100_TI3, AB3100_TI4, AB3100_TI5};
- unsigned char buf[6];
- u64 hw_counter = rtc_tm_to_time64(tm) * AB3100_RTC_CLOCK_RATE * 2;
- int err = 0;
- int i;
-
- buf[0] = (hw_counter) & 0xFF;
- buf[1] = (hw_counter >> 8) & 0xFF;
- buf[2] = (hw_counter >> 16) & 0xFF;
- buf[3] = (hw_counter >> 24) & 0xFF;
- buf[4] = (hw_counter >> 32) & 0xFF;
- buf[5] = (hw_counter >> 40) & 0xFF;
-
- for (i = 0; i < 6; i++) {
- err = abx500_set_register_interruptible(dev, 0,
- regs[i], buf[i]);
- if (err)
- return err;
- }
-
- /* Set the flag to mark that the clock is now set */
- return abx500_mask_and_set_register_interruptible(dev, 0,
- AB3100_RTC,
- 0x01, 0x01);
-
-}
-
-static int ab3100_rtc_read_time(struct device *dev, struct rtc_time *tm)
-{
- time64_t time;
- u8 rtcval;
- int err;
-
- err = abx500_get_register_interruptible(dev, 0,
- AB3100_RTC, &rtcval);
- if (err)
- return err;
-
- if (!(rtcval & 0x01)) {
- dev_info(dev, "clock not set (lost power)");
- return -EINVAL;
- } else {
- u64 hw_counter;
- u8 buf[6];
-
- /* Read out time registers */
- err = abx500_get_register_page_interruptible(dev, 0,
- AB3100_TI0,
- buf, 6);
- if (err != 0)
- return err;
-
- hw_counter = ((u64) buf[5] << 40) | ((u64) buf[4] << 32) |
- ((u64) buf[3] << 24) | ((u64) buf[2] << 16) |
- ((u64) buf[1] << 8) | (u64) buf[0];
- time = hw_counter / (u64) (AB3100_RTC_CLOCK_RATE * 2);
- }
-
- rtc_time64_to_tm(time, tm);
-
- return 0;
-}
-
-static int ab3100_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
-{
- time64_t time;
- u64 hw_counter;
- u8 buf[6];
- u8 rtcval;
- int err;
-
- /* Figure out if alarm is enabled or not */
- err = abx500_get_register_interruptible(dev, 0,
- 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 = abx500_get_register_page_interruptible(dev, 0,
- AB3100_AL0, buf, 4);
- if (err)
- return err;
- hw_counter = ((u64) buf[3] << 40) | ((u64) buf[2] << 32) |
- ((u64) buf[1] << 24) | ((u64) buf[0] << 16);
- time = hw_counter / (u64) (AB3100_RTC_CLOCK_RATE * 2);
-
- rtc_time64_to_tm(time, &alarm->time);
-
- return rtc_valid_tm(&alarm->time);
-}
-
-static int ab3100_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
-{
- u8 regs[] = {AB3100_AL0, AB3100_AL1, AB3100_AL2, AB3100_AL3};
- unsigned char buf[4];
- time64_t secs;
- u64 hw_counter;
- int err;
- int i;
-
- secs = rtc_tm_to_time64(&alarm->time);
- hw_counter = secs * AB3100_RTC_CLOCK_RATE * 2;
- buf[0] = (hw_counter >> 16) & 0xFF;
- buf[1] = (hw_counter >> 24) & 0xFF;
- buf[2] = (hw_counter >> 32) & 0xFF;
- buf[3] = (hw_counter >> 40) & 0xFF;
-
- /* Set the alarm */
- for (i = 0; i < 4; i++) {
- err = abx500_set_register_interruptible(dev, 0,
- regs[i], buf[i]);
- if (err)
- return err;
- }
- /* Then enable the alarm */
- return abx500_mask_and_set_register_interruptible(dev, 0,
- AB3100_RTC, (1 << 2),
- alarm->enabled << 2);
-}
-
-static int ab3100_rtc_irq_enable(struct device *dev, unsigned int enabled)
-{
- /*
- * 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 abx500_mask_and_set_register_interruptible(dev, 0,
- AB3100_RTC, (1 << 2),
- 1 << 2);
- else
- return abx500_mask_and_set_register_interruptible(dev, 0,
- AB3100_RTC, (1 << 2),
- 0);
-}
-
-static const struct rtc_class_ops ab3100_rtc_ops = {
- .read_time = ab3100_rtc_read_time,
- .set_time = ab3100_rtc_set_time,
- .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;
-
- /* The first RTC register needs special treatment */
- err = abx500_get_register_interruptible(&pdev->dev, 0,
- AB3100_RTC, ®val);
- 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 = abx500_set_register_interruptible(&pdev->dev, 0,
- AB3100_RTC, regval);
- /* Ignore any error on this write */
- }
-
- rtc = devm_rtc_allocate_device(&pdev->dev);
- if (IS_ERR(rtc))
- return PTR_ERR(rtc);
-
- rtc->ops = &ab3100_rtc_ops;
- /* 48bit counter at (AB3100_RTC_CLOCK_RATE * 2) */
- rtc->range_max = U32_MAX;
-
- platform_set_drvdata(pdev, rtc);
-
- return devm_rtc_register_device(rtc);
-}
-
-static struct platform_driver ab3100_rtc_driver = {
- .driver = {
- .name = "ab3100-rtc",
- },
-};
-
-module_platform_driver_probe(ab3100_rtc_driver, ab3100_rtc_probe);
-
-MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>");
-MODULE_DESCRIPTION("AB3100 RTC Driver");
-MODULE_LICENSE("GPL");
projects / linux-2.6-microblaze.git / commitdiff