diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/rtc/rtc-msm6242.c | 228 |
1 files changed, 228 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-msm6242.c b/drivers/rtc/rtc-msm6242.c new file mode 100644 index 000000000..80e364baa --- /dev/null +++ b/drivers/rtc/rtc-msm6242.c @@ -0,0 +1,228 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Oki MSM6242 RTC Driver + * + * Copyright 2009 Geert Uytterhoeven + * + * Based on the A2000 TOD code in arch/m68k/amiga/config.c + * Copyright (C) 1993 Hamish Macdonald + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/rtc.h> +#include <linux/slab.h> + + +enum { + MSM6242_SECOND1 = 0x0, /* 1-second digit register */ + MSM6242_SECOND10 = 0x1, /* 10-second digit register */ + MSM6242_MINUTE1 = 0x2, /* 1-minute digit register */ + MSM6242_MINUTE10 = 0x3, /* 10-minute digit register */ + MSM6242_HOUR1 = 0x4, /* 1-hour digit register */ + MSM6242_HOUR10 = 0x5, /* PM/AM, 10-hour digit register */ + MSM6242_DAY1 = 0x6, /* 1-day digit register */ + MSM6242_DAY10 = 0x7, /* 10-day digit register */ + MSM6242_MONTH1 = 0x8, /* 1-month digit register */ + MSM6242_MONTH10 = 0x9, /* 10-month digit register */ + MSM6242_YEAR1 = 0xa, /* 1-year digit register */ + MSM6242_YEAR10 = 0xb, /* 10-year digit register */ + MSM6242_WEEK = 0xc, /* Week register */ + MSM6242_CD = 0xd, /* Control Register D */ + MSM6242_CE = 0xe, /* Control Register E */ + MSM6242_CF = 0xf, /* Control Register F */ +}; + +#define MSM6242_HOUR10_AM (0 << 2) +#define MSM6242_HOUR10_PM (1 << 2) +#define MSM6242_HOUR10_HR_MASK (3 << 0) + +#define MSM6242_WEEK_SUNDAY 0 +#define MSM6242_WEEK_MONDAY 1 +#define MSM6242_WEEK_TUESDAY 2 +#define MSM6242_WEEK_WEDNESDAY 3 +#define MSM6242_WEEK_THURSDAY 4 +#define MSM6242_WEEK_FRIDAY 5 +#define MSM6242_WEEK_SATURDAY 6 + +#define MSM6242_CD_30_S_ADJ (1 << 3) /* 30-second adjustment */ +#define MSM6242_CD_IRQ_FLAG (1 << 2) +#define MSM6242_CD_BUSY (1 << 1) +#define MSM6242_CD_HOLD (1 << 0) + +#define MSM6242_CE_T_MASK (3 << 2) +#define MSM6242_CE_T_64HZ (0 << 2) /* period 1/64 second */ +#define MSM6242_CE_T_1HZ (1 << 2) /* period 1 second */ +#define MSM6242_CE_T_1MINUTE (2 << 2) /* period 1 minute */ +#define MSM6242_CE_T_1HOUR (3 << 2) /* period 1 hour */ + +#define MSM6242_CE_ITRPT_STND (1 << 1) +#define MSM6242_CE_MASK (1 << 0) /* STD.P output control */ + +#define MSM6242_CF_TEST (1 << 3) +#define MSM6242_CF_12H (0 << 2) +#define MSM6242_CF_24H (1 << 2) +#define MSM6242_CF_STOP (1 << 1) +#define MSM6242_CF_REST (1 << 0) /* reset */ + + +struct msm6242_priv { + u32 __iomem *regs; + struct rtc_device *rtc; +}; + +static inline unsigned int msm6242_read(struct msm6242_priv *priv, + unsigned int reg) +{ + return __raw_readl(&priv->regs[reg]) & 0xf; +} + +static inline void msm6242_write(struct msm6242_priv *priv, unsigned int val, + unsigned int reg) +{ + __raw_writel(val, &priv->regs[reg]); +} + +static void msm6242_lock(struct msm6242_priv *priv) +{ + int cnt = 5; + + msm6242_write(priv, MSM6242_CD_HOLD|MSM6242_CD_IRQ_FLAG, MSM6242_CD); + + while ((msm6242_read(priv, MSM6242_CD) & MSM6242_CD_BUSY) && cnt) { + msm6242_write(priv, MSM6242_CD_IRQ_FLAG, MSM6242_CD); + udelay(70); + msm6242_write(priv, MSM6242_CD_HOLD|MSM6242_CD_IRQ_FLAG, MSM6242_CD); + cnt--; + } + + if (!cnt) + pr_warn("timed out waiting for RTC (0x%x)\n", + msm6242_read(priv, MSM6242_CD)); +} + +static void msm6242_unlock(struct msm6242_priv *priv) +{ + msm6242_write(priv, MSM6242_CD_IRQ_FLAG, MSM6242_CD); +} + +static int msm6242_read_time(struct device *dev, struct rtc_time *tm) +{ + struct msm6242_priv *priv = dev_get_drvdata(dev); + + msm6242_lock(priv); + + tm->tm_sec = msm6242_read(priv, MSM6242_SECOND10) * 10 + + msm6242_read(priv, MSM6242_SECOND1); + tm->tm_min = msm6242_read(priv, MSM6242_MINUTE10) * 10 + + msm6242_read(priv, MSM6242_MINUTE1); + tm->tm_hour = (msm6242_read(priv, MSM6242_HOUR10) & + MSM6242_HOUR10_HR_MASK) * 10 + + msm6242_read(priv, MSM6242_HOUR1); + tm->tm_mday = msm6242_read(priv, MSM6242_DAY10) * 10 + + msm6242_read(priv, MSM6242_DAY1); + tm->tm_wday = msm6242_read(priv, MSM6242_WEEK); + tm->tm_mon = msm6242_read(priv, MSM6242_MONTH10) * 10 + + msm6242_read(priv, MSM6242_MONTH1) - 1; + tm->tm_year = msm6242_read(priv, MSM6242_YEAR10) * 10 + + msm6242_read(priv, MSM6242_YEAR1); + if (tm->tm_year <= 69) + tm->tm_year += 100; + + if (!(msm6242_read(priv, MSM6242_CF) & MSM6242_CF_24H)) { + unsigned int pm = msm6242_read(priv, MSM6242_HOUR10) & + MSM6242_HOUR10_PM; + if (!pm && tm->tm_hour == 12) + tm->tm_hour = 0; + else if (pm && tm->tm_hour != 12) + tm->tm_hour += 12; + } + + msm6242_unlock(priv); + + return 0; +} + +static int msm6242_set_time(struct device *dev, struct rtc_time *tm) +{ + struct msm6242_priv *priv = dev_get_drvdata(dev); + + msm6242_lock(priv); + + msm6242_write(priv, tm->tm_sec / 10, MSM6242_SECOND10); + msm6242_write(priv, tm->tm_sec % 10, MSM6242_SECOND1); + msm6242_write(priv, tm->tm_min / 10, MSM6242_MINUTE10); + msm6242_write(priv, tm->tm_min % 10, MSM6242_MINUTE1); + if (msm6242_read(priv, MSM6242_CF) & MSM6242_CF_24H) + msm6242_write(priv, tm->tm_hour / 10, MSM6242_HOUR10); + else if (tm->tm_hour >= 12) + msm6242_write(priv, MSM6242_HOUR10_PM + (tm->tm_hour - 12) / 10, + MSM6242_HOUR10); + else + msm6242_write(priv, tm->tm_hour / 10, MSM6242_HOUR10); + msm6242_write(priv, tm->tm_hour % 10, MSM6242_HOUR1); + msm6242_write(priv, tm->tm_mday / 10, MSM6242_DAY10); + msm6242_write(priv, tm->tm_mday % 10, MSM6242_DAY1); + if (tm->tm_wday != -1) + msm6242_write(priv, tm->tm_wday, MSM6242_WEEK); + msm6242_write(priv, (tm->tm_mon + 1) / 10, MSM6242_MONTH10); + msm6242_write(priv, (tm->tm_mon + 1) % 10, MSM6242_MONTH1); + if (tm->tm_year >= 100) + tm->tm_year -= 100; + msm6242_write(priv, tm->tm_year / 10, MSM6242_YEAR10); + msm6242_write(priv, tm->tm_year % 10, MSM6242_YEAR1); + + msm6242_unlock(priv); + return 0; +} + +static const struct rtc_class_ops msm6242_rtc_ops = { + .read_time = msm6242_read_time, + .set_time = msm6242_set_time, +}; + +static int __init msm6242_rtc_probe(struct platform_device *pdev) +{ + struct resource *res; + struct msm6242_priv *priv; + struct rtc_device *rtc; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return -ENODEV; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->regs = devm_ioremap(&pdev->dev, res->start, resource_size(res)); + if (!priv->regs) + return -ENOMEM; + platform_set_drvdata(pdev, priv); + + rtc = devm_rtc_device_register(&pdev->dev, "rtc-msm6242", + &msm6242_rtc_ops, THIS_MODULE); + if (IS_ERR(rtc)) + return PTR_ERR(rtc); + + priv->rtc = rtc; + return 0; +} + +static struct platform_driver msm6242_rtc_driver = { + .driver = { + .name = "rtc-msm6242", + }, +}; + +module_platform_driver_probe(msm6242_rtc_driver, msm6242_rtc_probe); + +MODULE_AUTHOR("Geert Uytterhoeven <geert@linux-m68k.org>"); +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Oki MSM6242 RTC driver"); +MODULE_ALIAS("platform:rtc-msm6242"); |