Re: [RFC PATCH 08/10] rtc: New driver for RTC in Netronix embedded controller

[Alexandre Belloni <alexandre.belloni-LDxbnhwyfcJBDgjK7y7TUQ@public.gmane.org>]

On 21/06/2020 00:42:19+0200, Jonathan Neuschäfer wrote:
> With this driver, mainline Linux can keep its time and date in sync with
> the vendor kernel.
> 
> Advanced functionality like alarm and automatic power-on is not yet
> supported.
> 

Please report the results of rtctest (from the kernel tree) and
rtc-range
(https://git.kernel.org/pub/scm/linux/kernel/git/abelloni/rtc-tools.git/tree/rtc-range.c)

> Signed-off-by: Jonathan Neuschäfer <j.neuschaefer-hi6Y0CQ0nG0@public.gmane.org>
> ---
>  drivers/rtc/Kconfig     |   4 ++
>  drivers/rtc/Makefile    |   1 +
>  drivers/rtc/rtc-ntxec.c | 115 ++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 120 insertions(+)
>  create mode 100644 drivers/rtc/rtc-ntxec.c
> 
> diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
> index b54d87d45c89b..2310d08933f9c 100644
> --- a/drivers/rtc/Kconfig
> +++ b/drivers/rtc/Kconfig
> @@ -1300,6 +1300,10 @@ config RTC_DRV_CROS_EC
>  	  This driver can also be built as a module. If so, the module
>  	  will be called rtc-cros-ec.
> 
> +config RTC_DRV_NTXEC
> +	tristate "Netronix embedded controller RTC driver"
> +	depends on MFD_NTXEC
> +

This should get an help section.


>  comment "on-CPU RTC drivers"
> 
>  config RTC_DRV_ASM9260
> diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
> index 0721752c6ed4c..8653d04aefa99 100644
> --- a/drivers/rtc/Makefile
> +++ b/drivers/rtc/Makefile
> @@ -111,6 +111,7 @@ obj-$(CONFIG_RTC_DRV_MT7622)	+= rtc-mt7622.o
>  obj-$(CONFIG_RTC_DRV_MV)	+= rtc-mv.o
>  obj-$(CONFIG_RTC_DRV_MXC)	+= rtc-mxc.o
>  obj-$(CONFIG_RTC_DRV_MXC_V2)	+= rtc-mxc_v2.o
> +obj-$(CONFIG_RTC_DRV_NTXEC)	+= rtc-ntxec.o
>  obj-$(CONFIG_RTC_DRV_OMAP)	+= rtc-omap.o
>  obj-$(CONFIG_RTC_DRV_OPAL)	+= rtc-opal.o
>  obj-$(CONFIG_RTC_DRV_PALMAS)	+= rtc-palmas.o
> diff --git a/drivers/rtc/rtc-ntxec.c b/drivers/rtc/rtc-ntxec.c
> new file mode 100644
> index 0000000000000..44d5a5eedb597
> --- /dev/null
> +++ b/drivers/rtc/rtc-ntxec.c
> @@ -0,0 +1,115 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +// Copyright 2020 Jonathan Neuschäfer
> +
> +#include <linux/rtc.h>
> +#include <linux/mfd/ntxec.h>
> +#include <linux/platform_device.h>
> +#include <linux/types.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>

Please sort the includes.

> +
> +struct ntxec_rtc {
> +	struct device *dev;
> +	struct ntxec *ec;
> +};
> +
> +#define NTXEC_WRITE_YEAR	0x10
> +#define NTXEC_WRITE_MONTH	0x11
> +#define NTXEC_WRITE_DAY		0x12
> +#define NTXEC_WRITE_HOUR	0x13
> +#define NTXEC_WRITE_MINUTE	0x14
> +#define NTXEC_WRITE_SECOND	0x15
> +
> +#define NTXEC_READ_YM		0x20
> +#define NTXEC_READ_DH		0x21
> +#define NTXEC_READ_MS		0x22
> +
> +
> +static int ntxec_read_time(struct device *dev, struct rtc_time *tm)
> +{
> +	struct ntxec_rtc *rtc = dev_get_drvdata(dev);
> +	int res;
> +
> +	res = ntxec_read16(rtc->ec, NTXEC_READ_YM);
> +	if (res < 0)
> +		return res;
> +
> +	tm->tm_year = (res >> 8) + 100;
> +	tm->tm_mon = (res & 0xff) - 1;
> +
> +	res = ntxec_read16(rtc->ec, NTXEC_READ_DH);
> +	if (res < 0)
> +		return res;
> +
> +	tm->tm_mday = res >> 8;
> +	tm->tm_hour = res & 0xff;
> +
> +	res = ntxec_read16(rtc->ec, NTXEC_READ_MS);
> +	if (res < 0)
> +		return res;
> +
> +	tm->tm_min = res >> 8;
> +	tm->tm_sec = res & 0xff;
> +
> +	return 0;
> +}
> +
> +static int ntxec_set_time(struct device *dev, struct rtc_time *tm)
> +{
> +	struct ntxec_rtc *rtc = dev_get_drvdata(dev);
> +	int res = 0;
> +
> +	res |= ntxec_write8(rtc->ec, NTXEC_WRITE_YEAR, tm->tm_year - 100);
> +	res |= ntxec_write8(rtc->ec, NTXEC_WRITE_MONTH, tm->tm_mon + 1);
> +	res |= ntxec_write8(rtc->ec, NTXEC_WRITE_DAY, tm->tm_mday);
> +	res |= ntxec_write8(rtc->ec, NTXEC_WRITE_HOUR, tm->tm_hour);
> +	res |= ntxec_write8(rtc->ec, NTXEC_WRITE_MINUTE, tm->tm_min);
> +	res |= ntxec_write8(rtc->ec, NTXEC_WRITE_SECOND, tm->tm_sec);
> +
> +	return (res < 0)? -EIO : 0;
> +}
> +
> +static const struct rtc_class_ops ntxec_rtc_ops = {
> +	.read_time		= ntxec_read_time,
> +	.set_time		= ntxec_set_time,
> +};
> +
> +static int ntxec_rtc_probe(struct platform_device *pdev)
> +{
> +	struct rtc_device *rtcdev;
> +	struct ntxec_rtc *rtc;
> +
> +	rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
> +	if (!rtc)
> +		return -ENOMEM;
> +
> +	rtc->dev = &pdev->dev;
> +	rtc->ec = dev_get_drvdata(pdev->dev.parent);
> +	platform_set_drvdata(pdev, rtc);
> +
> +	rtcdev = devm_rtc_device_register(&pdev->dev, "ntxec-rtc",
> +					  &ntxec_rtc_ops, THIS_MODULE);

Please use devm_rtc_allocate_device and rtc_register_device. Also, set
the supported range (->range_min and ->range_max).


-- 
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com