Hi,
2021年5月18日(火) 17:46 Hager Stefan <s.hager@xxxxxxxxx>:
>
> When the Micro Crystal RV3032 rtc is used with a primary coin-cell for power backup, the backup switching mode LSM (level switching mode) should be used according to the technical support from the manufacturer of this device.
>
> Currently there is no way to set this mode by the driver.
>
> Thererfore, i suggest to introduce an additional parameter for the devicetree to enable this backup switchover mode
> and to extend the probe function to look for that parameter and activate the LSM.
>
> Is this an appropriate solution? Does it need improvements?
>
> Signed-off-by: Stefan Hager <s.hager@xxxxxxxxx>
>
> ---
> diff --git a/Documentation/devicetree/bindings/rtc/microcrystal,rv3032.yaml b/Documentation/devicetree/bindings/rtc/microcrystal,rv3032.yaml
> index a2c55303810d..b948e19e358b 100644
> --- a/Documentation/devicetree/bindings/rtc/microcrystal,rv3032.yaml
> +++ b/Documentation/devicetree/bindings/rtc/microcrystal,rv3032.yaml
> @@ -37,6 +37,10 @@ properties:
> - 3000
> - 4400
>
> + backup-switchover-mode-level:
> + description:
> + Use level switching mode for backup switchover mode
Please add 'type: boolean'.
> +
> required:
> - compatible
> - reg
> diff --git a/drivers/rtc/rtc-rv3032.c b/drivers/rtc/rtc-rv3032.c
> index d63102d5cb1e..a28a3e0172d0 100644
> --- a/drivers/rtc/rtc-rv3032.c
> +++ b/drivers/rtc/rtc-rv3032.c
> @@ -881,6 +881,12 @@ static int rv3032_probe(struct i2c_client *client)
> if (ret)
> return ret;
>
> + if (device_property_read_bool(&client->dev, "backup-switchover-mode-level")) {
> + ret = regmap_update_bits(rv3032->regmap, RV3032_PMU, RV3032_PMU_BSM, (RV3032_PMU_BSM_LSM) << 4);
> + if (ret)
> + return ret;
> + }
> +
> rv3032_trickle_charger_setup(&client->dev, rv3032);
>
> rv3032->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
>
Best regards,
Nobuhiro
--
Nobuhiro Iwamatsu
iwamatsu at {nigauri.org / debian.org}
GPG ID: 40AD1FA6
