Re: [PATCH v4 2/2] eeprom: at24: Add support for address-width property

[Andy Shevchenko]

On Fri, 2018-06-29 at 15:21 +0800, alanx.chiang@xxxxxxxxx wrote:
> From: Alan Chiang <alanx.chiang@xxxxxxxxx>
> 
> Provide a flexible way to determine the addressing bits of eeprom.
> Pass the addressing bits to driver through address-width property.
> 

Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

> Signed-off-by: Alan Chiang <alanx.chiang@xxxxxxxxx>
> Signed-off-by: Andy Yeh <andy.yeh@xxxxxxxxx>
> 
> ---
> since v1
> -- Add a warn message for 8-bit addressing.
> since v2
> -- Modify the warning message for clear.
> -- Move the clearing bit operation outside of a statement.
> since v3
> -- Merge the warning message into one line.
> 
> ---
>  drivers/misc/eeprom/at24.c | 17 +++++++++++++++++
>  1 file changed, 17 insertions(+)
> 
> diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
> index 0c125f2..7ea640b 100644
> --- a/drivers/misc/eeprom/at24.c
> +++ b/drivers/misc/eeprom/at24.c
> @@ -478,6 +478,23 @@ static void at24_properties_to_pdata(struct
> device *dev,
>  	if (device_property_present(dev, "no-read-rollover"))
>  		chip->flags |= AT24_FLAG_NO_RDROL;
>  
> +	err = device_property_read_u32(dev, "address-width", &val);
> +	if (!err) {
> +		switch (val) {
> +		case 8:
> +			if (chip->flags & AT24_FLAG_ADDR16)
> +				dev_warn(dev, "Override address width
> to be 8, while default is 16\n");
> +			chip->flags &= ~AT24_FLAG_ADDR16;
> +			break;
> +		case 16:
> +			chip->flags |= AT24_FLAG_ADDR16;
> +			break;
> +		default:
> +			dev_warn(dev, "Bad \"address-width\"
> property: %u\n",
> +				 val);
> +		}
> +	}
> +
>  	err = device_property_read_u32(dev, "size", &val);
>  	if (!err)
>  		chip->byte_len = val;

-- 
Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Intel Finland Oy