From: Chen-Yu Tsai Date: Fri, 8 Jul 2016 14:33:38 +0000 (+0800) Subject: rtc: ac100: Add RTC driver for X-Powers AC100 X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=d00a18a42c1483924de086ddfb0efe8da1dba3ac;p=deliverable%2Flinux.git rtc: ac100: Add RTC driver for X-Powers AC100 X-Powers AC100 is a codec / RTC combo chip. This driver supports the RTC sub-device. The RTC block also has clock outputs and non-volatile storage. Non-volatile storage wthin the RTC hardware is not supported. Clock output support is added in the next patch. Signed-off-by: Chen-Yu Tsai Acked-by: Alexandre Belloni Signed-off-by: Lee Jones --- diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index e215f50794b6..7fc11cdfd27e 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -187,6 +187,16 @@ config RTC_DRV_ABX80X This driver can also be built as a module. If so, the module will be called rtc-abx80x. +config RTC_DRV_AC100 + tristate "X-Powers AC100" + depends on MFD_AC100 + help + If you say yes here you get support for the real-time clock found + in X-Powers AC100 family peripheral ICs. + + This driver can also be built as a module. If so, the module + will be called rtc-ac100. + config RTC_DRV_AS3722 tristate "ams AS3722 RTC driver" depends on MFD_AS3722 diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index 7cf7ad559c79..8fb994bacdf7 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -27,6 +27,7 @@ obj-$(CONFIG_RTC_DRV_AB3100) += rtc-ab3100.o obj-$(CONFIG_RTC_DRV_AB8500) += rtc-ab8500.o obj-$(CONFIG_RTC_DRV_ABB5ZES3) += rtc-ab-b5ze-s3.o obj-$(CONFIG_RTC_DRV_ABX80X) += rtc-abx80x.o +obj-$(CONFIG_RTC_DRV_AC100) += rtc-ac100.o obj-$(CONFIG_RTC_DRV_ARMADA38X) += rtc-armada38x.o obj-$(CONFIG_RTC_DRV_AS3722) += rtc-as3722.o obj-$(CONFIG_RTC_DRV_ASM9260) += rtc-asm9260.o diff --git a/drivers/rtc/rtc-ac100.c b/drivers/rtc/rtc-ac100.c new file mode 100644 index 000000000000..5a9ca89d04c7 --- /dev/null +++ b/drivers/rtc/rtc-ac100.c @@ -0,0 +1,325 @@ +/* + * RTC Driver for X-Powers AC100 + * + * Copyright (c) 2016 Chen-Yu Tsai + * + * Chen-Yu Tsai + * + * 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. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* Control register */ +#define AC100_RTC_CTRL_24HOUR BIT(0) + +/* RTC */ +#define AC100_RTC_SEC_MASK GENMASK(6, 0) +#define AC100_RTC_MIN_MASK GENMASK(6, 0) +#define AC100_RTC_HOU_MASK GENMASK(5, 0) +#define AC100_RTC_WEE_MASK GENMASK(2, 0) +#define AC100_RTC_DAY_MASK GENMASK(5, 0) +#define AC100_RTC_MON_MASK GENMASK(4, 0) +#define AC100_RTC_YEA_MASK GENMASK(7, 0) +#define AC100_RTC_YEA_LEAP BIT(15) +#define AC100_RTC_UPD_TRIGGER BIT(15) + +/* Alarm (wall clock) */ +#define AC100_ALM_INT_ENABLE BIT(0) + +#define AC100_ALM_SEC_MASK GENMASK(6, 0) +#define AC100_ALM_MIN_MASK GENMASK(6, 0) +#define AC100_ALM_HOU_MASK GENMASK(5, 0) +#define AC100_ALM_WEE_MASK GENMASK(2, 0) +#define AC100_ALM_DAY_MASK GENMASK(5, 0) +#define AC100_ALM_MON_MASK GENMASK(4, 0) +#define AC100_ALM_YEA_MASK GENMASK(7, 0) +#define AC100_ALM_ENABLE_FLAG BIT(15) +#define AC100_ALM_UPD_TRIGGER BIT(15) + +/* + * The year parameter passed to the driver is usually an offset relative to + * the year 1900. This macro is used to convert this offset to another one + * relative to the minimum year allowed by the hardware. + * + * The year range is 1970 - 2069. This range is selected to match Allwinner's + * driver. + */ +#define AC100_YEAR_MIN 1970 +#define AC100_YEAR_MAX 2069 +#define AC100_YEAR_OFF (AC100_YEAR_MIN - 1900) + +struct ac100_rtc_dev { + struct rtc_device *rtc; + struct device *dev; + struct regmap *regmap; + int irq; + unsigned long alarm; +}; + +static int ac100_rtc_get_time(struct device *dev, struct rtc_time *rtc_tm) +{ + struct ac100_rtc_dev *chip = dev_get_drvdata(dev); + struct regmap *regmap = chip->regmap; + u16 reg[7]; + int ret; + + ret = regmap_bulk_read(regmap, AC100_RTC_SEC, reg, 7); + if (ret) + return ret; + + rtc_tm->tm_sec = bcd2bin(reg[0] & AC100_RTC_SEC_MASK); + rtc_tm->tm_min = bcd2bin(reg[1] & AC100_RTC_MIN_MASK); + rtc_tm->tm_hour = bcd2bin(reg[2] & AC100_RTC_HOU_MASK); + rtc_tm->tm_wday = bcd2bin(reg[3] & AC100_RTC_WEE_MASK); + rtc_tm->tm_mday = bcd2bin(reg[4] & AC100_RTC_DAY_MASK); + rtc_tm->tm_mon = bcd2bin(reg[5] & AC100_RTC_MON_MASK) - 1; + rtc_tm->tm_year = bcd2bin(reg[6] & AC100_RTC_YEA_MASK) + + AC100_YEAR_OFF; + + return rtc_valid_tm(rtc_tm); +} + +static int ac100_rtc_set_time(struct device *dev, struct rtc_time *rtc_tm) +{ + struct ac100_rtc_dev *chip = dev_get_drvdata(dev); + struct regmap *regmap = chip->regmap; + int year; + u16 reg[8]; + + /* our RTC has a limited year range... */ + year = rtc_tm->tm_year - AC100_YEAR_OFF; + if (year < 0 || year > (AC100_YEAR_MAX - 1900)) { + dev_err(dev, "rtc only supports year in range %d - %d\n", + AC100_YEAR_MIN, AC100_YEAR_MAX); + return -EINVAL; + } + + /* convert to BCD */ + reg[0] = bin2bcd(rtc_tm->tm_sec) & AC100_RTC_SEC_MASK; + reg[1] = bin2bcd(rtc_tm->tm_min) & AC100_RTC_MIN_MASK; + reg[2] = bin2bcd(rtc_tm->tm_hour) & AC100_RTC_HOU_MASK; + reg[3] = bin2bcd(rtc_tm->tm_wday) & AC100_RTC_WEE_MASK; + reg[4] = bin2bcd(rtc_tm->tm_mday) & AC100_RTC_DAY_MASK; + reg[5] = bin2bcd(rtc_tm->tm_mon + 1) & AC100_RTC_MON_MASK; + reg[6] = bin2bcd(year) & AC100_RTC_YEA_MASK; + /* trigger write */ + reg[7] = AC100_RTC_UPD_TRIGGER; + + /* Is it a leap year? */ + if (is_leap_year(year + AC100_YEAR_OFF + 1900)) + reg[6] |= AC100_RTC_YEA_LEAP; + + return regmap_bulk_write(regmap, AC100_RTC_SEC, reg, 8); +} + +static int ac100_rtc_alarm_irq_enable(struct device *dev, unsigned int en) +{ + struct ac100_rtc_dev *chip = dev_get_drvdata(dev); + struct regmap *regmap = chip->regmap; + unsigned int val; + + val = en ? AC100_ALM_INT_ENABLE : 0; + + return regmap_write(regmap, AC100_ALM_INT_ENA, val); +} + +static int ac100_rtc_get_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct ac100_rtc_dev *chip = dev_get_drvdata(dev); + struct regmap *regmap = chip->regmap; + struct rtc_time *alrm_tm = &alrm->time; + u16 reg[7]; + unsigned int val; + int ret; + + ret = regmap_read(regmap, AC100_ALM_INT_ENA, &val); + if (ret) + return ret; + + alrm->enabled = !!(val & AC100_ALM_INT_ENABLE); + + ret = regmap_bulk_read(regmap, AC100_ALM_SEC, reg, 7); + if (ret) + return ret; + + alrm_tm->tm_sec = bcd2bin(reg[0] & AC100_ALM_SEC_MASK); + alrm_tm->tm_min = bcd2bin(reg[1] & AC100_ALM_MIN_MASK); + alrm_tm->tm_hour = bcd2bin(reg[2] & AC100_ALM_HOU_MASK); + alrm_tm->tm_wday = bcd2bin(reg[3] & AC100_ALM_WEE_MASK); + alrm_tm->tm_mday = bcd2bin(reg[4] & AC100_ALM_DAY_MASK); + alrm_tm->tm_mon = bcd2bin(reg[5] & AC100_ALM_MON_MASK) - 1; + alrm_tm->tm_year = bcd2bin(reg[6] & AC100_ALM_YEA_MASK) + + AC100_YEAR_OFF; + + return 0; +} + +static int ac100_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct ac100_rtc_dev *chip = dev_get_drvdata(dev); + struct regmap *regmap = chip->regmap; + struct rtc_time *alrm_tm = &alrm->time; + u16 reg[8]; + int year; + int ret; + + /* our alarm has a limited year range... */ + year = alrm_tm->tm_year - AC100_YEAR_OFF; + if (year < 0 || year > (AC100_YEAR_MAX - 1900)) { + dev_err(dev, "alarm only supports year in range %d - %d\n", + AC100_YEAR_MIN, AC100_YEAR_MAX); + return -EINVAL; + } + + /* convert to BCD */ + reg[0] = (bin2bcd(alrm_tm->tm_sec) & AC100_ALM_SEC_MASK) | + AC100_ALM_ENABLE_FLAG; + reg[1] = (bin2bcd(alrm_tm->tm_min) & AC100_ALM_MIN_MASK) | + AC100_ALM_ENABLE_FLAG; + reg[2] = (bin2bcd(alrm_tm->tm_hour) & AC100_ALM_HOU_MASK) | + AC100_ALM_ENABLE_FLAG; + /* Do not enable weekday alarm */ + reg[3] = bin2bcd(alrm_tm->tm_wday) & AC100_ALM_WEE_MASK; + reg[4] = (bin2bcd(alrm_tm->tm_mday) & AC100_ALM_DAY_MASK) | + AC100_ALM_ENABLE_FLAG; + reg[5] = (bin2bcd(alrm_tm->tm_mon + 1) & AC100_ALM_MON_MASK) | + AC100_ALM_ENABLE_FLAG; + reg[6] = (bin2bcd(year) & AC100_ALM_YEA_MASK) | + AC100_ALM_ENABLE_FLAG; + /* trigger write */ + reg[7] = AC100_ALM_UPD_TRIGGER; + + ret = regmap_bulk_write(regmap, AC100_ALM_SEC, reg, 8); + if (ret) + return ret; + + return ac100_rtc_alarm_irq_enable(dev, alrm->enabled); +} + +static irqreturn_t ac100_rtc_irq(int irq, void *data) +{ + struct ac100_rtc_dev *chip = data; + struct regmap *regmap = chip->regmap; + unsigned int val = 0; + int ret; + + mutex_lock(&chip->rtc->ops_lock); + + /* read status */ + ret = regmap_read(regmap, AC100_ALM_INT_STA, &val); + if (ret) + goto out; + + if (val & AC100_ALM_INT_ENABLE) { + /* signal rtc framework */ + rtc_update_irq(chip->rtc, 1, RTC_AF | RTC_IRQF); + + /* clear status */ + ret = regmap_write(regmap, AC100_ALM_INT_STA, val); + if (ret) + goto out; + + /* disable interrupt */ + ret = ac100_rtc_alarm_irq_enable(chip->dev, 0); + if (ret) + goto out; + } + +out: + mutex_unlock(&chip->rtc->ops_lock); + return IRQ_HANDLED; +} + +static const struct rtc_class_ops ac100_rtc_ops = { + .read_time = ac100_rtc_get_time, + .set_time = ac100_rtc_set_time, + .read_alarm = ac100_rtc_get_alarm, + .set_alarm = ac100_rtc_set_alarm, + .alarm_irq_enable = ac100_rtc_alarm_irq_enable, +}; + +static int ac100_rtc_probe(struct platform_device *pdev) +{ + struct ac100_dev *ac100 = dev_get_drvdata(pdev->dev.parent); + struct ac100_rtc_dev *chip; + int ret; + + chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL); + platform_set_drvdata(pdev, chip); + chip->dev = &pdev->dev; + chip->regmap = ac100->regmap; + + chip->irq = platform_get_irq(pdev, 0); + if (chip->irq < 0) { + dev_err(&pdev->dev, "No IRQ resource\n"); + return chip->irq; + } + + ret = devm_request_threaded_irq(&pdev->dev, chip->irq, NULL, + ac100_rtc_irq, + IRQF_SHARED | IRQF_ONESHOT, + dev_name(&pdev->dev), chip); + if (ret) { + dev_err(&pdev->dev, "Could not request IRQ\n"); + return ret; + } + + /* always use 24 hour mode */ + regmap_write_bits(chip->regmap, AC100_RTC_CTRL, AC100_RTC_CTRL_24HOUR, + AC100_RTC_CTRL_24HOUR); + + /* disable counter alarm interrupt */ + regmap_write(chip->regmap, AC100_ALM_INT_ENA, 0); + + /* clear counter alarm pending interrupts */ + regmap_write(chip->regmap, AC100_ALM_INT_STA, AC100_ALM_INT_ENABLE); + + chip->rtc = devm_rtc_device_register(&pdev->dev, "rtc-ac100", + &ac100_rtc_ops, THIS_MODULE); + if (IS_ERR(chip->rtc)) { + dev_err(&pdev->dev, "unable to register device\n"); + return PTR_ERR(chip->rtc); + } + + dev_info(&pdev->dev, "RTC enabled\n"); + + return 0; +} + +static const struct of_device_id ac100_rtc_match[] = { + { .compatible = "x-powers,ac100-rtc" }, + { }, +}; +MODULE_DEVICE_TABLE(of, ac100_rtc_match); + +static struct platform_driver ac100_rtc_driver = { + .probe = ac100_rtc_probe, + .driver = { + .name = "ac100-rtc", + .of_match_table = of_match_ptr(ac100_rtc_match), + }, +}; +module_platform_driver(ac100_rtc_driver); + +MODULE_DESCRIPTION("X-Powers AC100 RTC driver"); +MODULE_AUTHOR("Chen-Yu Tsai "); +MODULE_LICENSE("GPL v2");