On 9/10/2020 04:41, Thomas Bogendoerfer wrote:
> ds1685_rtc_begin_data_access() tried to access an extended register before
> enabling access to it by switching to bank 1. Depending on content in NVRAM
> this could lead to an endless loop. While at it fix also switch back to
> bank 0 in ds1685_rtc_end_data_access().
>
> Signed-off-by: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
> ---
> drivers/rtc/rtc-ds1685.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/rtc/rtc-ds1685.c b/drivers/rtc/rtc-ds1685.c
> index 56c670af2e50..dfbd7b88b2b9 100644
> --- a/drivers/rtc/rtc-ds1685.c
> +++ b/drivers/rtc/rtc-ds1685.c
> @@ -193,12 +193,12 @@ ds1685_rtc_begin_data_access(struct ds1685_priv *rtc)
> rtc->write(rtc, RTC_CTRL_B,
> (rtc->read(rtc, RTC_CTRL_B) | RTC_CTRL_B_SET));
>
> + /* Switch to Bank 1 */
> + ds1685_rtc_switch_to_bank1(rtc);
> +
> /* Read Ext Ctrl 4A and check the INCR bit to avoid a lockout. */
> while (rtc->read(rtc, RTC_EXT_CTRL_4A) & RTC_CTRL_4A_INCR)
> cpu_relax();
> -
> - /* Switch to Bank 1 */
> - ds1685_rtc_switch_to_bank1(rtc);
> }
>
> /**
> @@ -213,7 +213,7 @@ static inline void
> ds1685_rtc_end_data_access(struct ds1685_priv *rtc)
> {
> /* Switch back to Bank 0 */
> - ds1685_rtc_switch_to_bank1(rtc);
> + ds1685_rtc_switch_to_bank0(rtc);
>
> /* Clear the SET bit in Ctrl B */
> rtc->write(rtc, RTC_CTRL_B,
>
This probably needs to be sent to stable as well.
Acked-by: Joshua Kinard <kumba@xxxxxxxxxx>
