linux-kernel - Re: [PATCH 5/6] rtc: rv3029: enable AE_x bits on set

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Date:	Sat, 23 Apr 2016 01:37:16 +0200
From:	Alexandre Belloni <alexandre.belloni@...e-electrons.com>
To:	Mylène Josserand 
	<mylene.josserand@...e-electrons.com>
Cc:	rtc-linux@...glegroups.com,
	Alessandro Zummo <a.zummo@...ertech.it>,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 5/6] rtc: rv3029: enable AE_x bits on set_alarm

On 21/04/2016 at 20:24:18 +0200, Mylène Josserand wrote :
> The RTC RV3029 handles different types of alarms : seconds, minutes, ...
> These alarms can be enabled or disabled individually using an AE_x bit
> which is the last bit (BIT(7)) on each alarm registers.
> 
> To prepare the alarm IRQ support, the current code enables all the alarm
> types by setting each AE_x to 1.
> It also fixes month and weekday errors : it was performing -1 instead
> of +1.
> 
> Signed-off-by: Mylène Josserand <mylene.josserand@...e-electrons.com>
> ---
>  drivers/rtc/rtc-rv3029c2.c | 23 ++++++++++++++++-------
>  1 file changed, 16 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/rtc/rtc-rv3029c2.c b/drivers/rtc/rtc-rv3029c2.c
> index a849005..42de1a3 100644
> --- a/drivers/rtc/rtc-rv3029c2.c
> +++ b/drivers/rtc/rtc-rv3029c2.c
> @@ -76,6 +76,7 @@
>  #define RV3029_A_DW			0x14
>  #define RV3029_A_MO			0x15
>  #define RV3029_A_YR			0x16
> +#define RV3029_A_AE_X			BIT(7)
>  #define RV3029_ALARM_SECTION_LEN	0x07
>  
>  /* timer section */
> @@ -436,14 +437,22 @@ static int rv3029_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
>  		dev_err(dev, "%s: reading SR failed\n", __func__);
>  		return -EIO;
>  	}
> -	regs[RV3029_A_SC - RV3029_A_SC] = bin2bcd(tm->tm_sec & 0x7f);
> -	regs[RV3029_A_MN - RV3029_A_SC] = bin2bcd(tm->tm_min & 0x7f);
> -	regs[RV3029_A_HR - RV3029_A_SC] = bin2bcd(tm->tm_hour & 0x3f);
> -	regs[RV3029_A_DT - RV3029_A_SC] = bin2bcd(tm->tm_mday & 0x3f);
> -	regs[RV3029_A_MO - RV3029_A_SC] = bin2bcd((tm->tm_mon & 0x1f) - 1);
> -	regs[RV3029_A_DW - RV3029_A_SC] = bin2bcd((tm->tm_wday & 7) - 1);
> -	regs[RV3029_A_YR - RV3029_A_SC] = bin2bcd((tm->tm_year & 0x7f) - 100);
>  
> +	/* Activate all the alarms with AE_x bit */
> +	regs[RV3029_A_SC - RV3029_A_SC] = (bin2bcd(tm->tm_sec)) | RV3029_A_AE_X;
> +	regs[RV3029_A_MN - RV3029_A_SC] = (bin2bcd(tm->tm_min)) | RV3029_A_AE_X;
> +	regs[RV3029_A_HR - RV3029_A_SC] = (bin2bcd(tm->tm_hour & 0x3f))
> +		| RV3029_A_AE_X;
> +	regs[RV3029_A_DT - RV3029_A_SC] = (bin2bcd(tm->tm_mday & 0x3f))
> +		| RV3029_A_AE_X;
> +	regs[RV3029_A_MO - RV3029_A_SC] = (bin2bcd((tm->tm_mon & 0x1f) + 1))
> +		| RV3029_A_AE_X;
> +	regs[RV3029_A_DW - RV3029_A_SC] = (bin2bcd((tm->tm_wday & 7) + 1))
> +		| RV3029_A_AE_X;
> +	regs[RV3029_A_YR - RV3029_A_SC] = (bin2bcd((tm->tm_year) - 100))
> +		| RV3029_A_AE_X;
> +

Alarms probably never worked anyway because this still suffers form
another bug:
(bin2bcd(tm->tm_hour & 0x3f)) should be (bin2bcd(tm->tm_hour) & 0x3f),
and the same for the other members.

note that (bin2bcd((tm->tm_mon & 0x1f) + 1)) must be
(bin2bcd(tm->tm_mon + 1) & 0x1f)

etc...

> +	/* Write the alarm */
>  	ret = rv3029_write_regs(dev, RV3029_A_SC, regs,
>  				RV3029_ALARM_SECTION_LEN);
>  	if (ret < 0)
> -- 
> 2.8.0.rc3
> 

-- 
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com