target/linux/bcm27xx/patches-6.1/950-1252-Improvement-on-backup-switchover-mode-overlay-value-.patch

   1 From f85acc3d0fb33ce5c92578dca7b1345915f744ff Mon Sep 17 00:00:00 2001
   2 From: Tiago Freire <41837236+tiagofreire-pt@users.noreply.github.com>
   3 Date: Tue, 23 Jan 2024 12:10:24 +0000
   4 Subject: [PATCH 1252/1295] Improvement on backup-switchover-mode overlay value
   5  definitions (#5884)
   6
   7 For the RV3028 RTC, the definitions for its `backup-switchover-mode` overlay
   8 were not intelligible neither complete/exhaustive.
   9
  10 Accordingly to the https://github.com/raspberrypi/linux/issues/2912#issuecomment-477670051
  11 these one here proposed should be correct.
  12
  13 `/boot/config.txt` should be as a configuration example, for rv3028, on a
  14  Uputronics GPS Extension HAT:
  15
  16     # For GPS Expansion Board from Uputronics
  17     dtparam=i2c_arm=on
  18     dtoverlay=i2c-rtc,rv3028,backup-switchover-mode=3
  19     dtoverlay=pps-gpio,gpiopin=18
  20     init_uart_baud=115200
  21
  22 From my tests (`sudo rmmod rtc_rv3028 && sudo i2cget -y 1 0x52 0x37`):
  23
  24 `Default from factory`: `0x10`
  25 `Mode 0`: `0x10`
  26 `Mode 1`: `0x14`
  27 `Mode 2`: `0x18`
  28 `Mode 3`: `0x1c`
  29
  30 `Mode 3`: `0x1c` is consistent with the manufacturer configuration script: http://store.uputronics.com/files/configure-rv3028.sh
  31 ---
  32  arch/arm/boot/dts/overlays/README | 8 +++++++-
  33  1 file changed, 7 insertions(+), 1 deletion(-)
  34
  35 --- a/arch/arm/boot/dts/overlays/README
  36 +++ b/arch/arm/boot/dts/overlays/README
  37 @@ -2106,7 +2106,13 @@ Params: abx80x                  Select o
  38                                  source
  39
  40          backup-switchover-mode  Backup power supply switch mode. Must be 0 for
  41 -                                off or 1 for Vdd < VBackup (RV3028, RV3032)
  42 +                                "Switchover disabled", 1 for "Direct Switching"
  43 +                                (if Vdd < VBackup), 2 for "Standby
  44 +                                Mode" (if Vdd < Vbackup,
  45 +                                does not draw current) or 3 for
  46 +                                "Level Switching" (if Vdd < Vbackup
  47 +                                and Vdd < Vddsw and Vbackup > Vddsw)
  48 +                                (RV3028, RV3032)
  49
  50
  51  Name:   i2c-rtc-gpio