u-boot/drivers/power
Fabrice Gasnier 8b8c99bd3e power: regulator: stm32: vrefbuf: fix a possible overshoot when re-enabling
There maybe an overshoot:
- when disabling, then re-enabling vrefbuf too quickly
- or upon platform reset as external capacitor maybe slow
  discharging (VREFBUF is HiZ at reset by default).
VREFBUF is used by ADC/DAC on some boards. An overshoot on the reference
voltage make the conversions inaccurate for a short period of time. So:
- Don't put the VREFBUF in HiZ when disabling, to force an active
  discharge.
- Enforce a 1ms OFF/ON delay, also upon reset

Penalty is a 1ms delay is applied (even for a cold boot), when enabling
VREFBUF.

Fixes: 93cf0ae775 ("power: regulator: Add support for stm32-vrefbuf")

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Reviewed-by: Patrice Chotard <patrice.chotard@st.com>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
2020-07-07 16:01:23 +02:00
..
acpi_pmc common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
battery common: Drop linux/delay.h from common header 2020-05-18 21:19:23 -04:00
domain common: Drop linux/bitops.h from common header 2020-05-18 21:19:23 -04:00
fuel_gauge common: Drop linux/delay.h from common header 2020-05-18 21:19:23 -04:00
mfd common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
pmic power: pmic: Add SPL Kconfig entry for PFUZE100 2020-06-08 10:42:50 +02:00
regulator power: regulator: stm32: vrefbuf: fix a possible overshoot when re-enabling 2020-07-07 16:01:23 +02:00
axp152.c command: Remove the cmd_tbl_t typedef 2020-05-18 18:36:55 -04:00
axp209.c common: Drop linux/delay.h from common header 2020-05-18 21:19:23 -04:00
axp221.c command: Remove the cmd_tbl_t typedef 2020-05-18 18:36:55 -04:00
axp809.c command: Remove the cmd_tbl_t typedef 2020-05-18 18:36:55 -04:00
axp818.c command: Remove the cmd_tbl_t typedef 2020-05-18 18:36:55 -04:00
exynos-tmu.c common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
ftpmu010.c SPDX: Convert all of our single license tags to Linux Kernel style 2018-05-07 09:34:12 -04:00
Kconfig poweroff: add poweroff for mt6323 pmic 2020-01-10 10:25:13 -05:00
Makefile poweroff: add poweroff for mt6323 pmic 2020-01-10 10:25:13 -05:00
mt6323.c common: Drop linux/delay.h from common header 2020-05-18 21:19:23 -04:00
palmas.c power: make most tps drivers and the twl4030 driver compatible with DM_I2C 2018-12-10 06:17:30 +01:00
power_core.c common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
power_dialog.c common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
power_fsl.c SPDX: Convert all of our single license tags to Linux Kernel style 2018-05-07 09:34:12 -04:00
power_i2c.c common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
power_spi.c SPDX: Convert all of our single license tags to Linux Kernel style 2018-05-07 09:34:12 -04:00
sy8106a.c SPDX: Convert all of our single license tags to Linux Kernel style 2018-05-07 09:34:12 -04:00
tps6586x.c common: Drop linux/delay.h from common header 2020-05-18 21:19:23 -04:00
twl4030.c common: Drop linux/delay.h from common header 2020-05-18 21:19:23 -04:00
twl6030.c common: Drop linux/delay.h from common header 2020-05-18 21:19:23 -04:00