PATCH V2 2025-08-23 12:33:18: Changes: * improved commit description of main fix * new patch: adds a restriction of historical no-battery-detection logic to the bq27000 chip
PATCH V1 2025-07-21 14:46:09:
H. Nikolaus Schaller (2): power: supply: bq27xxx: fix error return in case of no bq27000 hdq battery power: supply: bq27xxx: restrict no-battery detection to bq27000
drivers/power/supply/bq27xxx_battery.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
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 ---
Notes: Changes to v1: * improved commit description of main fix
drivers/power/supply/bq27xxx_battery.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/power/supply/bq27xxx_battery.c b/drivers/power/supply/bq27xxx_battery.c index c3616b1c07e6f..dadd8754a73a8 100644 --- a/drivers/power/supply/bq27xxx_battery.c +++ b/drivers/power/supply/bq27xxx_battery.c @@ -1945,7 +1945,7 @@ static void bq27xxx_battery_update_unlocked(struct bq27xxx_device_info *di)
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.capacity = bq27xxx_battery_read_soc(di);
…
So we change the detection of missing bq27000 battery to simply set
…
See also: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Docu...
Regards, Markus
On Sat, Aug 23, 2025 at 04:46:46PM +0200, Markus Elfring wrote:
…
So we change the detection of missing bq27000 battery to simply set
…
See also: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Docu...
Regards, Markus
Hi,
This is the semi-friendly patch-bot of Greg Kroah-Hartman.
Markus, you seem to have sent a nonsensical or otherwise pointless review comment to a patch submission on a Linux kernel developer mailing list. I strongly suggest that you not do this anymore. Please do not bother developers who are actively working to produce patches and features with comments that, in the end, are a waste of time.
Patch submitter, please ignore Markus's suggestion; you do not need to follow it at all. The person/bot/AI that sent it is being ignored by almost all Linux kernel maintainers for having a persistent pattern of behavior of producing distracting and pointless commentary, and inability to adapt to feedback. Please feel free to also ignore emails from them.
thanks,
greg k-h's patch email bot
There are fuel gauges in the bq27xxx series (e.g. bq27z561) which may in some cases report 0xff as the value of BQ27XXX_REG_FLAGS that should not be interpreted as "no battery" like for a disconnected battery with some built in bq27000 chip.
So restrict the no-battery detection originally introduced by
commit 3dd843e1c26a ("bq27000: report missing device better.")
to the bq27000.
There is no need to backport further because this was hidden before
commit f16d9fb6cf03 ("power: supply: bq27xxx: Retrieve again when busy")
Fixes: f16d9fb6cf03 ("power: supply: bq27xxx: Retrieve again when busy") Suggested-by: Jerry Lv Jerry.Lv@axis.com Cc: stable@vger.kernel.org Signed-off-by: H. Nikolaus Schaller hns@goldelico.com --- drivers/power/supply/bq27xxx_battery.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/power/supply/bq27xxx_battery.c b/drivers/power/supply/bq27xxx_battery.c index dadd8754a73a8..3363af24017ae 100644 --- a/drivers/power/supply/bq27xxx_battery.c +++ b/drivers/power/supply/bq27xxx_battery.c @@ -1944,8 +1944,8 @@ static void bq27xxx_battery_update_unlocked(struct bq27xxx_device_info *di) bool has_singe_flag = di->opts & BQ27XXX_O_ZERO;
cache.flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, has_singe_flag); - if ((cache.flags & 0xff) == 0xff) - cache.flags = -ENODEV; /* read error */ + if (di->chip == BQ27000 && (cache.flags & 0xff) == 0xff) + cache.flags = -ENODEV; /* bq27000 hdq read error */ if (cache.flags >= 0) { cache.capacity = bq27xxx_battery_read_soc(di);
linux-stable-mirror@lists.linaro.org
-
Greg KH -
H. Nikolaus Schaller -
Markus Elfring