diff options
Diffstat (limited to 'drivers/rtc/rtc-ftrtc010.c')
| -rw-r--r-- | drivers/rtc/rtc-ftrtc010.c | 222 |
1 files changed, 222 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-ftrtc010.c b/drivers/rtc/rtc-ftrtc010.c new file mode 100644 index 000000000..25c6e7d95 --- /dev/null +++ b/drivers/rtc/rtc-ftrtc010.c @@ -0,0 +1,222 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Faraday Technology FTRTC010 driver + * + * Copyright (C) 2009 Janos Laube <janos.dev@gmail.com> + * + * Original code for older kernel 2.6.15 are from Stormlinksemi + * first update from Janos Laube for > 2.6.29 kernels + * + * checkpatch fixes and usage of rtc-lib code + * Hans Ulli Kroll <ulli.kroll@googlemail.com> + */ + +#include <linux/rtc.h> +#include <linux/io.h> +#include <linux/slab.h> +#include <linux/platform_device.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mod_devicetable.h> +#include <linux/clk.h> + +#define DRV_NAME "rtc-ftrtc010" + +MODULE_AUTHOR("Hans Ulli Kroll <ulli.kroll@googlemail.com>"); +MODULE_DESCRIPTION("RTC driver for Gemini SoC"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:" DRV_NAME); + +struct ftrtc010_rtc { + struct rtc_device *rtc_dev; + void __iomem *rtc_base; + int rtc_irq; + struct clk *pclk; + struct clk *extclk; +}; + +enum ftrtc010_rtc_offsets { + FTRTC010_RTC_SECOND = 0x00, + FTRTC010_RTC_MINUTE = 0x04, + FTRTC010_RTC_HOUR = 0x08, + FTRTC010_RTC_DAYS = 0x0C, + FTRTC010_RTC_ALARM_SECOND = 0x10, + FTRTC010_RTC_ALARM_MINUTE = 0x14, + FTRTC010_RTC_ALARM_HOUR = 0x18, + FTRTC010_RTC_RECORD = 0x1C, + FTRTC010_RTC_CR = 0x20, +}; + +static irqreturn_t ftrtc010_rtc_interrupt(int irq, void *dev) +{ + return IRQ_HANDLED; +} + +/* + * Looks like the RTC in the Gemini SoC is (totaly) broken + * We can't read/write directly the time from RTC registers. + * We must do some "offset" calculation to get the real time + * + * This FIX works pretty fine and Stormlinksemi aka Cortina-Networks does + * the same thing, without the rtc-lib.c calls. + */ + +static int ftrtc010_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + struct ftrtc010_rtc *rtc = dev_get_drvdata(dev); + + u32 days, hour, min, sec, offset; + timeu64_t time; + + sec = readl(rtc->rtc_base + FTRTC010_RTC_SECOND); + min = readl(rtc->rtc_base + FTRTC010_RTC_MINUTE); + hour = readl(rtc->rtc_base + FTRTC010_RTC_HOUR); + days = readl(rtc->rtc_base + FTRTC010_RTC_DAYS); + offset = readl(rtc->rtc_base + FTRTC010_RTC_RECORD); + + time = offset + days * 86400 + hour * 3600 + min * 60 + sec; + + rtc_time64_to_tm(time, tm); + + return 0; +} + +static int ftrtc010_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct ftrtc010_rtc *rtc = dev_get_drvdata(dev); + u32 sec, min, hour, day, offset; + timeu64_t time; + + time = rtc_tm_to_time64(tm); + + sec = readl(rtc->rtc_base + FTRTC010_RTC_SECOND); + min = readl(rtc->rtc_base + FTRTC010_RTC_MINUTE); + hour = readl(rtc->rtc_base + FTRTC010_RTC_HOUR); + day = readl(rtc->rtc_base + FTRTC010_RTC_DAYS); + + offset = time - (day * 86400 + hour * 3600 + min * 60 + sec); + + writel(offset, rtc->rtc_base + FTRTC010_RTC_RECORD); + writel(0x01, rtc->rtc_base + FTRTC010_RTC_CR); + + return 0; +} + +static const struct rtc_class_ops ftrtc010_rtc_ops = { + .read_time = ftrtc010_rtc_read_time, + .set_time = ftrtc010_rtc_set_time, +}; + +static int ftrtc010_rtc_probe(struct platform_device *pdev) +{ + u32 days, hour, min, sec; + struct ftrtc010_rtc *rtc; + struct device *dev = &pdev->dev; + struct resource *res; + int ret; + + rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL); + if (unlikely(!rtc)) + return -ENOMEM; + platform_set_drvdata(pdev, rtc); + + rtc->pclk = devm_clk_get(dev, "PCLK"); + if (IS_ERR(rtc->pclk)) { + dev_err(dev, "could not get PCLK\n"); + } else { + ret = clk_prepare_enable(rtc->pclk); + if (ret) { + dev_err(dev, "failed to enable PCLK\n"); + return ret; + } + } + rtc->extclk = devm_clk_get(dev, "EXTCLK"); + if (IS_ERR(rtc->extclk)) { + dev_err(dev, "could not get EXTCLK\n"); + } else { + ret = clk_prepare_enable(rtc->extclk); + if (ret) { + dev_err(dev, "failed to enable EXTCLK\n"); + goto err_disable_pclk; + } + } + + rtc->rtc_irq = platform_get_irq(pdev, 0); + if (rtc->rtc_irq < 0) { + ret = rtc->rtc_irq; + goto err_disable_extclk; + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + ret = -ENODEV; + goto err_disable_extclk; + } + + rtc->rtc_base = devm_ioremap(dev, res->start, + resource_size(res)); + if (!rtc->rtc_base) { + ret = -ENOMEM; + goto err_disable_extclk; + } + + rtc->rtc_dev = devm_rtc_allocate_device(dev); + if (IS_ERR(rtc->rtc_dev)) { + ret = PTR_ERR(rtc->rtc_dev); + goto err_disable_extclk; + } + + rtc->rtc_dev->ops = &ftrtc010_rtc_ops; + + sec = readl(rtc->rtc_base + FTRTC010_RTC_SECOND); + min = readl(rtc->rtc_base + FTRTC010_RTC_MINUTE); + hour = readl(rtc->rtc_base + FTRTC010_RTC_HOUR); + days = readl(rtc->rtc_base + FTRTC010_RTC_DAYS); + + rtc->rtc_dev->range_min = (u64)days * 86400 + hour * 3600 + + min * 60 + sec; + rtc->rtc_dev->range_max = U32_MAX + rtc->rtc_dev->range_min; + + ret = devm_request_irq(dev, rtc->rtc_irq, ftrtc010_rtc_interrupt, + IRQF_SHARED, pdev->name, dev); + if (unlikely(ret)) + goto err_disable_extclk; + + return devm_rtc_register_device(rtc->rtc_dev); + +err_disable_extclk: + clk_disable_unprepare(rtc->extclk); +err_disable_pclk: + clk_disable_unprepare(rtc->pclk); + return ret; +} + +static int ftrtc010_rtc_remove(struct platform_device *pdev) +{ + struct ftrtc010_rtc *rtc = platform_get_drvdata(pdev); + + if (!IS_ERR(rtc->extclk)) + clk_disable_unprepare(rtc->extclk); + if (!IS_ERR(rtc->pclk)) + clk_disable_unprepare(rtc->pclk); + + return 0; +} + +static const struct of_device_id ftrtc010_rtc_dt_match[] = { + { .compatible = "cortina,gemini-rtc" }, + { .compatible = "faraday,ftrtc010" }, + { } +}; +MODULE_DEVICE_TABLE(of, ftrtc010_rtc_dt_match); + +static struct platform_driver ftrtc010_rtc_driver = { + .driver = { + .name = DRV_NAME, + .of_match_table = ftrtc010_rtc_dt_match, + }, + .probe = ftrtc010_rtc_probe, + .remove = ftrtc010_rtc_remove, +}; + +module_platform_driver_probe(ftrtc010_rtc_driver, ftrtc010_rtc_probe); |