Re: [PATCH] rtc: abx80x: Implement procfs interface

[Alexandre Belloni <alexandre.belloni@free-electrons.com>]

Hi Marek,

On 23/06/2019 14:08:54+0200, Marek Vasut wrote:
> Implement procfs interface for polling battery status of the RTC
> via /proc/driver/rtc .
> 

Please don't, this interface is deprecated and doesn't work well. Use
RTC_VL_READ instead.

> Signed-off-by: Marek Vasut <marex@denx.de>
> Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
> ---
>  drivers/rtc/rtc-abx80x.c | 24 ++++++++++++++++++++++++
>  1 file changed, 24 insertions(+)
> 
> diff --git a/drivers/rtc/rtc-abx80x.c b/drivers/rtc/rtc-abx80x.c
> index 73830670a41f..4fab024fb508 100644
> --- a/drivers/rtc/rtc-abx80x.c
> +++ b/drivers/rtc/rtc-abx80x.c
> @@ -78,6 +78,10 @@
>  
>  #define ABX8XX_REG_ID0		0x28
>  
> +#define ABX8XX_REG_ANA_STATUS	0x2f
> +#define ABX8XX_ANA_BREFD	BIT(7)
> +#define ABX8XX_ANA_BMIN		BIT(6)
> +
>  #define ABX8XX_REG_OUT_CTRL	0x30
>  #define ABX8XX_OUT_CTRL_EXDS	BIT(4)
>  
> @@ -548,6 +552,25 @@ static int abx80x_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
>  	}
>  }
>  
> +static int abx80x_proc(struct device *dev, struct seq_file *seq)
> +{
> +	struct i2c_client *client = to_i2c_client(dev);
> +	int status, tmp;
> +
> +	status = i2c_smbus_read_byte_data(client, ABX8XX_REG_ANA_STATUS);
> +	if (status < 0)
> +		return status;
> +
> +	if (status & ABX8XX_ANA_BREFD)
> +		seq_printf(seq, "battery\t\t: ok\n");
> +	else if (status & ABX8XX_ANA_BMIN)
> +		seq_printf(seq, "battery\t\t: low\n");
> +	else
> +		seq_printf(seq, "battery\t\t: exhausted\n");
> +
> +	return 0;
> +}
> +
>  static const struct rtc_class_ops abx80x_rtc_ops = {
>  	.read_time	= abx80x_rtc_read_time,
>  	.set_time	= abx80x_rtc_set_time,
> @@ -555,6 +578,7 @@ static const struct rtc_class_ops abx80x_rtc_ops = {
>  	.set_alarm	= abx80x_set_alarm,
>  	.alarm_irq_enable = abx80x_alarm_irq_enable,
>  	.ioctl		= abx80x_ioctl,
> +	.proc		= abx80x_proc,
>  };
>  
>  static int abx80x_dt_trickle_cfg(struct device_node *np)
> -- 
> 2.20.1
> 

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