Re: [PATCH v2 2/2] eeprom: at24: Add support for address-width property
From: Sakari Ailus
Date: Tue Jun 26 2018 - 02:47:48 EST
Hi Alan,
On Tue, Jun 26, 2018 at 02:22:08PM +0800, alanx.chiang@xxxxxxxxx wrote:
> From: "alanx.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.
>
> 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.
>
> ---
> drivers/misc/eeprom/at24.c | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)
>
> diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
> index 0c125f2..231afcd 100644
> --- a/drivers/misc/eeprom/at24.c
> +++ b/drivers/misc/eeprom/at24.c
> @@ -478,6 +478,22 @@ 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:
> + chip->flags &= ~AT24_FLAG_ADDR16;
> + dev_warn(dev, "address-width is 8, clear the ADD16 bit\n");
Even though the default is 8 address bits, I don't see a need to issue a
warning if the address-width property sets that to 8 explicitly. I.e. only
warn if the flag was set.
> + 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;
--
Regards,
Sakari Ailus
sakari.ailus@xxxxxxxxxxxxxxx