| Message ID | 20170820013632.18375-3-afaerber@suse.de |
|---|---|
| State | New |
| Headers | show |
| Series | [RFC,1/3] dt-bindings: rtc: Add Realtek RTD1295 | expand |
Hi, On 20/08/2017 at 03:36:30 +0200, Andreas Färber wrote: > +static int rtd119x_rtc_read_time(struct device *dev, struct rtc_time *tm) > +{ > + struct rtd119x_rtc *data = dev_get_drvdata(dev); > + time64_t t; > + u32 day; > + > + day = readl_relaxed(data->base + RTD_RTCDATE_LOW); > + day |= readl_relaxed(data->base + RTD_RTCDATE_HIGH) << 8; Is RTD_RTCDATE_HIGH latched when RTD_RTCDATE_LOW is read? If this is not the case, you probably want to handle a possible update between both readl_relaxed. > + t = mktime64(data->base_year, 1, 1, 0, 0, 0); > + t += day * 24 * 60 * 60; > + rtc_time64_to_tm(t, tm); > + tm->tm_sec = readl_relaxed(data->base + RTD_RTCSEC) >> 1; > + tm->tm_min = readl_relaxed(data->base + RTD_RTCMIN); > + tm->tm_hour = readl_relaxed(data->base + RTD_RTCHR); > + > + return rtc_valid_tm(tm); > +} > + > +static int rtd119x_rtc_set_time(struct device *dev, struct rtc_time *tm) > +{ > + struct rtd119x_rtc *data = dev_get_drvdata(dev); > + time64_t time_base, new_time, time_delta; > + unsigned long day; > + > + if (tm->tm_year < data->base_year) > + return -EINVAL; > + > + time_base = mktime64(data->base_year, 1, 1, 0, 0, 0); > + new_time = rtc_tm_to_time64(tm); > + time_delta = new_time - time_base; > + day = time_delta / (24 * 60 * 60); > + if (day > 0x7fff) > + return -EINVAL; > + > + rtd119x_rtc_set_enabled(dev, false); > + > + writel_relaxed(tm->tm_sec, data->base + RTD_RTCSEC); > + writel_relaxed(tm->tm_min, data->base + RTD_RTCMIN); > + writel_relaxed(tm->tm_hour, data->base + RTD_RTCHR); > + writel_relaxed(day & 0xff, data->base + RTD_RTCDATE_LOW); > + writel_relaxed((day >> 8) & 0x7f, data->base + RTD_RTCDATE_HIGH); > + > + rtd119x_rtc_set_enabled(dev, true); > + > + return 0; > +} > + > +static int rtd119x_rtc_open(struct device *dev) > +{ > + struct rtd119x_rtc *data = dev_get_drvdata(dev); > + u32 val; > + int ret; > + > + ret = clk_prepare_enable(data->clk); > + if (ret) > + return ret; > + > + val = readl_relaxed(data->base + RTD_RTCACR); > + dev_info(dev, "rtcacr = 0x%08x\n", val); > + if (!(val & BIT(7))) { > + } I don't see the point of reading that register, and not doing anything with it. > + > + rtd119x_rtc_set_enabled(dev, true); > + This is certainly not what you want. The RTC device is usually not opened so enabling the RTC when open and disabling it when closed will not work on most systems. This is probably true for the clock too. i.e what you do here should be done in probe. > + return 0; > +} > + > +static void rtd119x_rtc_release(struct device *dev) > +{ > + struct rtd119x_rtc *data = dev_get_drvdata(dev); > + > + rtd119x_rtc_set_enabled(dev, false); > + > + clk_disable_unprepare(data->clk); > +} > + > +static const struct rtc_class_ops rtd119x_rtc_ops = { > + .open = rtd119x_rtc_open, > + .release = rtd119x_rtc_release, > + .read_time = rtd119x_rtc_read_time, > + .set_time = rtd119x_rtc_set_time, > +}; > + > +static const struct of_device_id rtd119x_rtc_dt_ids[] = { > + { .compatible = "realtek,rtd1295-rtc" }, > + { } > +}; > + > +static int rtd119x_rtc_probe(struct platform_device *pdev) > +{ > + struct rtd119x_rtc *data; > + struct resource *res; > + > + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); > + if (!data) > + return -ENOMEM; > + > + platform_set_drvdata(pdev, data); > + data->base_year = 2014; > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + data->base = devm_ioremap_resource(&pdev->dev, res); > + if (IS_ERR(data->base)) > + return PTR_ERR(data->base); > + > + data->clk = of_clk_get(pdev->dev.of_node, 0); > + if (IS_ERR(data->clk)) > + return PTR_ERR(data->clk); > + > + data->rtcdev = devm_rtc_device_register(&pdev->dev, "rtc", > + &rtd119x_rtc_ops, THIS_MODULE); > + if (IS_ERR(data->rtcdev)) { > + dev_err(&pdev->dev, "failed to register rtc device"); > + clk_put(data->clk); > + return PTR_ERR(data->rtcdev); > + } > + > + return 0; > +} > + > +static struct platform_driver rtd119x_rtc_driver = { > + .probe = rtd119x_rtc_probe, > + .driver = { > + .name = "rtd1295-rtc", > + .of_match_table = rtd119x_rtc_dt_ids, > + }, > +}; > +builtin_platform_driver(rtd119x_rtc_driver); > -- > 2.12.3 > -- Alexandre Belloni, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com
> +static void rtd119x_rtc_set_enabled(struct device *dev, bool enable) > +{ > + struct rtd119x_rtc *data = dev_get_drvdata(dev); > + u32 val; > + > + val = readl_relaxed(data->base + RTD_RTCEN); > + dev_info(dev, "%s: rtcen = 0x%08x\n", __func__, val); dev_dbg()? > +static int rtd119x_rtc_open(struct device *dev) > +{ > + struct rtd119x_rtc *data = dev_get_drvdata(dev); > + u32 val; > + int ret; > + > + ret = clk_prepare_enable(data->clk); > + if (ret) > + return ret; > + > + val = readl_relaxed(data->base + RTD_RTCACR); > + dev_info(dev, "rtcacr = 0x%08x\n", val); dev_dbg()? Andrew
Hi Alexandre, Am 20.08.2017 um 10:32 schrieb Alexandre Belloni: > On 20/08/2017 at 03:36:30 +0200, Andreas Färber wrote: >> +static int rtd119x_rtc_read_time(struct device *dev, struct rtc_time *tm) >> +{ >> + struct rtd119x_rtc *data = dev_get_drvdata(dev); >> + time64_t t; >> + u32 day; >> + >> + day = readl_relaxed(data->base + RTD_RTCDATE_LOW); >> + day |= readl_relaxed(data->base + RTD_RTCDATE_HIGH) << 8; > > Is RTD_RTCDATE_HIGH latched when RTD_RTCDATE_LOW is read? I do not have an answer to that. > If this is not > the case, you probably want to handle a possible update between both > readl_relaxed. Are you proposing to disable the RTC while reading the registers, or something related to my choice of _relaxed? (it follows an explanation by Marc Zyngier on the irq mux series) Inconsistencies might not be limited to the date. >> + t = mktime64(data->base_year, 1, 1, 0, 0, 0); >> + t += day * 24 * 60 * 60; >> + rtc_time64_to_tm(t, tm); BTW is there any more efficient way to get from year+days to day/month/year without going via seconds? >> + tm->tm_sec = readl_relaxed(data->base + RTD_RTCSEC) >> 1; >> + tm->tm_min = readl_relaxed(data->base + RTD_RTCMIN); >> + tm->tm_hour = readl_relaxed(data->base + RTD_RTCHR); >> + >> + return rtc_valid_tm(tm); >> +} >> + >> +static int rtd119x_rtc_set_time(struct device *dev, struct rtc_time *tm) >> +{ >> + struct rtd119x_rtc *data = dev_get_drvdata(dev); >> + time64_t time_base, new_time, time_delta; >> + unsigned long day; >> + >> + if (tm->tm_year < data->base_year) >> + return -EINVAL; >> + >> + time_base = mktime64(data->base_year, 1, 1, 0, 0, 0); >> + new_time = rtc_tm_to_time64(tm); >> + time_delta = new_time - time_base; >> + day = time_delta / (24 * 60 * 60); >> + if (day > 0x7fff) >> + return -EINVAL; >> + >> + rtd119x_rtc_set_enabled(dev, false); >> + >> + writel_relaxed(tm->tm_sec, data->base + RTD_RTCSEC); >> + writel_relaxed(tm->tm_min, data->base + RTD_RTCMIN); >> + writel_relaxed(tm->tm_hour, data->base + RTD_RTCHR); >> + writel_relaxed(day & 0xff, data->base + RTD_RTCDATE_LOW); >> + writel_relaxed((day >> 8) & 0x7f, data->base + RTD_RTCDATE_HIGH); >> + >> + rtd119x_rtc_set_enabled(dev, true); >> + >> + return 0; >> +} >> + >> +static int rtd119x_rtc_open(struct device *dev) >> +{ >> + struct rtd119x_rtc *data = dev_get_drvdata(dev); >> + u32 val; >> + int ret; >> + >> + ret = clk_prepare_enable(data->clk); >> + if (ret) >> + return ret; >> + >> + val = readl_relaxed(data->base + RTD_RTCACR); >> + dev_info(dev, "rtcacr = 0x%08x\n", val); >> + if (!(val & BIT(7))) { >> + } > > I don't see the point of reading that register, and not doing anything > with it. Thanks for spotting this. The story is that the old downstream has code for this case, but in my testing I didn't run into that path and forgot. Explanations are largely missing in the vendor code. That code should probably be added here in v2 and the dev_info() dropped, rather than dropping the current no-op expression. >> + >> + rtd119x_rtc_set_enabled(dev, true); >> + > > This is certainly not what you want. The RTC device is usually not > opened so enabling the RTC when open and disabling it when closed will > not work on most systems. This is probably true for the clock too. i.e > what you do here should be done in probe. I did test the probe path to work, but I can change it again. The downstream code had it in probe, but looking at rtc_class_ops I saw those hooks and thought they'd serve a purpose - what are they for then? (Any chance you can improve the documentation comments to avoid such misunderstandings? :)) >> + return 0; >> +} [snip] Regards, Andreas -- SUSE Linux GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany GF: Felix Imendörffer, Jane Smithard, Graham Norton HRB 21284 (AG Nürnberg)
Am 20.08.2017 um 17:40 schrieb Andrew Lunn: >> +static void rtd119x_rtc_set_enabled(struct device *dev, bool enable) >> +{ >> + struct rtd119x_rtc *data = dev_get_drvdata(dev); >> + u32 val; >> + >> + val = readl_relaxed(data->base + RTD_RTCEN); >> + dev_info(dev, "%s: rtcen = 0x%08x\n", __func__, val); > > dev_dbg()? > >> +static int rtd119x_rtc_open(struct device *dev) >> +{ >> + struct rtd119x_rtc *data = dev_get_drvdata(dev); >> + u32 val; >> + int ret; >> + >> + ret = clk_prepare_enable(data->clk); >> + if (ret) >> + return ret; >> + >> + val = readl_relaxed(data->base + RTD_RTCACR); >> + dev_info(dev, "rtcacr = 0x%08x\n", val); > > dev_dbg()? Yeah, either that or dropping them altogether. Thanks, Andreas -- SUSE Linux GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany GF: Felix Imendörffer, Jane Smithard, Graham Norton HRB 21284 (AG Nürnberg)
On 20/08/2017 at 23:10:16 +0200, Andreas Färber wrote: > > Is RTD_RTCDATE_HIGH latched when RTD_RTCDATE_LOW is read? > > I do not have an answer to that. > > > If this is not > > the case, you probably want to handle a possible update between both > > readl_relaxed. > > Are you proposing to disable the RTC while reading the registers, or > something related to my choice of _relaxed? (it follows an explanation > by Marc Zyngier on the irq mux series) Inconsistencies might not be > limited to the date. > A simple way to be sure would be to read RTD_RTCSEC first, then the other registers and check RTD_RTCSEC didn't change. This will ensure the other registers have not be updated in the meantime (unless it takes one minute but I doubt this is the case). if RTD_RTCSEC changed, then you can start over. > >> + t = mktime64(data->base_year, 1, 1, 0, 0, 0); > >> + t += day * 24 * 60 * 60; > >> + rtc_time64_to_tm(t, tm); > > BTW is there any more efficient way to get from year+days to > day/month/year without going via seconds? > Completely untested: for (y = data->base_year; (day - (365 + is_leap_year(y))) > 0; y++) day -= (365 + is_leap_year(y)); for (m = 0; (day - rtc_month_days(m, y)) > 0; m++) day -= rtc_month_days(m, y); > >> + > >> + rtd119x_rtc_set_enabled(dev, true); > >> + > > > > This is certainly not what you want. The RTC device is usually not > > opened so enabling the RTC when open and disabling it when closed will > > not work on most systems. This is probably true for the clock too. i.e > > what you do here should be done in probe. > > I did test the probe path to work, but I can change it again. The > downstream code had it in probe, but looking at rtc_class_ops I saw > those hooks and thought they'd serve a purpose - what are they for then? > (Any chance you can improve the documentation comments to avoid such > misunderstandings? :)) > They are (were) used only when the rtc character device (/dev/rtcx) is opened/released but the cdev interface is one of many interfaces to the RTC sod it doesn't make sense to do something only in that case (especially requesting IRQs). To solve your concern, this is what I'm going to apply after fixing the two remaining uses of .release: http://patchwork.ozlabs.org/patch/804707/ -- Alexandre Belloni, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index 72419ac2c52a..882828b1b351 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -1765,6 +1765,14 @@ config RTC_DRV_CPCAP Say y here for CPCAP rtc found on some Motorola phones and tablets such as Droid 4. +config RTC_DRV_RTD119X + bool "Realtek RTD129x RTC" + depends on ARCH_REALTEK || COMPILE_TEST + default ARCH_REALTEK + help + If you say yes here, you get support for the RTD1295 SoC + Real Time Clock. + comment "HID Sensor RTC drivers" config RTC_DRV_HID_SENSOR_TIME diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index acd366b41c85..55a0a5ca45b0 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -131,6 +131,7 @@ obj-$(CONFIG_RTC_DRV_RP5C01) += rtc-rp5c01.o obj-$(CONFIG_RTC_DRV_RS5C313) += rtc-rs5c313.o obj-$(CONFIG_RTC_DRV_RS5C348) += rtc-rs5c348.o obj-$(CONFIG_RTC_DRV_RS5C372) += rtc-rs5c372.o +obj-$(CONFIG_RTC_DRV_RTD119X) += rtc-rtd119x.o obj-$(CONFIG_RTC_DRV_RV3029C2) += rtc-rv3029c2.o obj-$(CONFIG_RTC_DRV_RV8803) += rtc-rv8803.o obj-$(CONFIG_RTC_DRV_RX4581) += rtc-rx4581.o diff --git a/drivers/rtc/rtc-rtd119x.c b/drivers/rtc/rtc-rtd119x.c new file mode 100644 index 000000000000..b532e127b56e --- /dev/null +++ b/drivers/rtc/rtc-rtd119x.c @@ -0,0 +1,175 @@ +/* + * Realtek RTD129x RTC + * + * Copyright (c) 2017 Andreas Färber + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/platform_device.h> +#include <linux/rtc.h> + +#define RTD_RTCSEC 0x00 +#define RTD_RTCMIN 0x04 +#define RTD_RTCHR 0x08 +#define RTD_RTCDATE_LOW 0x0c +#define RTD_RTCDATE_HIGH 0x10 +#define RTD_RTCACR 0x28 +#define RTD_RTCEN 0x2c + +struct rtd119x_rtc { + void __iomem *base; + struct clk *clk; + struct rtc_device *rtcdev; + unsigned base_year; +}; + +static void rtd119x_rtc_set_enabled(struct device *dev, bool enable) +{ + struct rtd119x_rtc *data = dev_get_drvdata(dev); + u32 val; + + val = readl_relaxed(data->base + RTD_RTCEN); + dev_info(dev, "%s: rtcen = 0x%08x\n", __func__, val); + if (enable) { + if ((val & 0xff) == 0x5a) + return; + writel_relaxed(0x5a, data->base + RTD_RTCEN); + } else { + writel_relaxed(0, data->base + RTD_RTCEN); + } +} + +static int rtd119x_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + struct rtd119x_rtc *data = dev_get_drvdata(dev); + time64_t t; + u32 day; + + day = readl_relaxed(data->base + RTD_RTCDATE_LOW); + day |= readl_relaxed(data->base + RTD_RTCDATE_HIGH) << 8; + t = mktime64(data->base_year, 1, 1, 0, 0, 0); + t += day * 24 * 60 * 60; + rtc_time64_to_tm(t, tm); + tm->tm_sec = readl_relaxed(data->base + RTD_RTCSEC) >> 1; + tm->tm_min = readl_relaxed(data->base + RTD_RTCMIN); + tm->tm_hour = readl_relaxed(data->base + RTD_RTCHR); + + return rtc_valid_tm(tm); +} + +static int rtd119x_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct rtd119x_rtc *data = dev_get_drvdata(dev); + time64_t time_base, new_time, time_delta; + unsigned long day; + + if (tm->tm_year < data->base_year) + return -EINVAL; + + time_base = mktime64(data->base_year, 1, 1, 0, 0, 0); + new_time = rtc_tm_to_time64(tm); + time_delta = new_time - time_base; + day = time_delta / (24 * 60 * 60); + if (day > 0x7fff) + return -EINVAL; + + rtd119x_rtc_set_enabled(dev, false); + + writel_relaxed(tm->tm_sec, data->base + RTD_RTCSEC); + writel_relaxed(tm->tm_min, data->base + RTD_RTCMIN); + writel_relaxed(tm->tm_hour, data->base + RTD_RTCHR); + writel_relaxed(day & 0xff, data->base + RTD_RTCDATE_LOW); + writel_relaxed((day >> 8) & 0x7f, data->base + RTD_RTCDATE_HIGH); + + rtd119x_rtc_set_enabled(dev, true); + + return 0; +} + +static int rtd119x_rtc_open(struct device *dev) +{ + struct rtd119x_rtc *data = dev_get_drvdata(dev); + u32 val; + int ret; + + ret = clk_prepare_enable(data->clk); + if (ret) + return ret; + + val = readl_relaxed(data->base + RTD_RTCACR); + dev_info(dev, "rtcacr = 0x%08x\n", val); + if (!(val & BIT(7))) { + } + + rtd119x_rtc_set_enabled(dev, true); + + return 0; +} + +static void rtd119x_rtc_release(struct device *dev) +{ + struct rtd119x_rtc *data = dev_get_drvdata(dev); + + rtd119x_rtc_set_enabled(dev, false); + + clk_disable_unprepare(data->clk); +} + +static const struct rtc_class_ops rtd119x_rtc_ops = { + .open = rtd119x_rtc_open, + .release = rtd119x_rtc_release, + .read_time = rtd119x_rtc_read_time, + .set_time = rtd119x_rtc_set_time, +}; + +static const struct of_device_id rtd119x_rtc_dt_ids[] = { + { .compatible = "realtek,rtd1295-rtc" }, + { } +}; + +static int rtd119x_rtc_probe(struct platform_device *pdev) +{ + struct rtd119x_rtc *data; + struct resource *res; + + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + platform_set_drvdata(pdev, data); + data->base_year = 2014; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + data->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(data->base)) + return PTR_ERR(data->base); + + data->clk = of_clk_get(pdev->dev.of_node, 0); + if (IS_ERR(data->clk)) + return PTR_ERR(data->clk); + + data->rtcdev = devm_rtc_device_register(&pdev->dev, "rtc", + &rtd119x_rtc_ops, THIS_MODULE); + if (IS_ERR(data->rtcdev)) { + dev_err(&pdev->dev, "failed to register rtc device"); + clk_put(data->clk); + return PTR_ERR(data->rtcdev); + } + + return 0; +} + +static struct platform_driver rtd119x_rtc_driver = { + .probe = rtd119x_rtc_probe, + .driver = { + .name = "rtd1295-rtc", + .of_match_table = rtd119x_rtc_dt_ids, + }, +}; +builtin_platform_driver(rtd119x_rtc_driver);
Based on QNAP's mach-rtk119x/driver/rtk_rtc_drv.c code. Signed-off-by: Andreas Färber <afaerber@suse.de> --- drivers/rtc/Kconfig | 8 +++ drivers/rtc/Makefile | 1 + drivers/rtc/rtc-rtd119x.c | 175 ++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 184 insertions(+) create mode 100644 drivers/rtc/rtc-rtd119x.c -- 2.12.3