[PATCH 0/3] hwmon: bt1-pvt: Fix PVT sensor being unpowered

From: Serge Semin
Date: Sun Sep 20 2020 - 07:09:54 EST


Baikal-T1 PVT sensor has got a dedicated power domain with 1.8V intended
to be supplied via the external GPVT and VPVT_18 pins. In case if the
power isn't supplied, the sensor IO registers will be accessible, but the
data conversion just won't happen. The situation of the power loss
currently will cause the temperature and voltage read procedures to hang
up. The problem is fixed in the framework of this patchset firstly by
checking whether the conversion works at the sensor probe procedure, and
secondly by keeping the current conversion update timeout in the private
driver data cache and using it to set the wait-completion timeout.

Fixes: 87976ce2825d ("hwmon: Add Baikal-T1 PVT sensor driver")
Signed-off-by: Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx>
Cc: Maxim Kaurkin <Maxim.Kaurkin@xxxxxxxxxxxxxxxxxxxx>
Cc: Alexey Malahov <Alexey.Malahov@xxxxxxxxxxxxxxxxxxxx>
Cc: Pavel Parkhomenko <Pavel.Parkhomenko@xxxxxxxxxxxxxxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxxx
Cc: linux-hwmon@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx

Serge Semin (3):
hwmon: bt1-pvt: Test sensor power supply on probe
hwmon: bt1-pvt: Cache current update timeout
hwmon: bt1-pvt: Wait for the completion with timeout

drivers/hwmon/bt1-pvt.c | 138 ++++++++++++++++++++++++++++------------
drivers/hwmon/bt1-pvt.h | 3 +
2 files changed, 101 insertions(+), 40 deletions(-)

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2.27.0