5.4-stable review patch. If anyone has any objections, please let me know.
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From: H. Nikolaus Schaller hns@goldelico.com
commit 2c334d038466ac509468fbe06905a32d202117db upstream.
Since commit
commit f16d9fb6cf03 ("power: supply: bq27xxx: Retrieve again when busy")
the console log of some devices with hdq enabled but no bq27000 battery (like e.g. the Pandaboard) is flooded with messages like:
[ 34.247833] power_supply bq27000-battery: driver failed to report 'status' property: -1
as soon as user-space is finding a /sys entry and trying to read the "status" property.
It turns out that the offending commit changes the logic to now return the value of cache.flags if it is <0. This is likely under the assumption that it is an error number. In normal errors from bq27xxx_read() this is indeed the case.
But there is special code to detect if no bq27000 is installed or accessible through hdq/1wire and wants to report this. In that case, the cache.flags are set historically by
commit 3dd843e1c26a ("bq27000: report missing device better.")
to constant -1 which did make reading properties return -ENODEV. So everything appeared to be fine before the return value was passed upwards.
Now the -1 is returned as -EPERM instead of -ENODEV, triggering the error condition in power_supply_format_property() which then floods the console log.
So we change the detection of missing bq27000 battery to simply set
cache.flags = -ENODEV
instead of -1.
Fixes: f16d9fb6cf03 ("power: supply: bq27xxx: Retrieve again when busy") Cc: Jerry Lv Jerry.Lv@axis.com Cc: stable@vger.kernel.org Signed-off-by: H. Nikolaus Schaller hns@goldelico.com Link: https://lore.kernel.org/r/692f79eb6fd541adb397038ea6e750d4de2deddf.175594529... Signed-off-by: Sebastian Reichel sebastian.reichel@collabora.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/power/supply/bq27xxx_battery.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/power/supply/bq27xxx_battery.c +++ b/drivers/power/supply/bq27xxx_battery.c @@ -1553,7 +1553,7 @@ static void bq27xxx_battery_update_unloc
cache.flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, has_singe_flag); if ((cache.flags & 0xff) == 0xff) - cache.flags = -1; /* read error */ + cache.flags = -ENODEV; /* read error */ if (cache.flags >= 0) { cache.temperature = bq27xxx_battery_read_temperature(di); if (has_ci_flag && (cache.flags & BQ27000_FLAG_CI)) {