On Thu, 12 Jun 2014, Lan Tianyu wrote: > Some machines'(E,G Lenovo Z480) ECs are not stable during boot up > and causes battery driver fails to be probed due to failure of getting > battery information from EC sometimes. After several retries, the > operation will work. This patch is to retry to get battery information 5 > times if the first try fails. > > Reported-and-tested-by: naszar <naszar@xxxxx> > Reference: https://bugzilla.kernel.org/show_bug.cgi?id=75581 > Cc: stable@xxxxxxxxxxxxxxx > Signed-off-by: Lan Tianyu <tianyu.lan@xxxxxxxxx> > --- > drivers/acpi/battery.c | 12 +++++++++++- > 1 file changed, 11 insertions(+), 1 deletion(-) > > diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c > index e48fc98..485009d 100644 > --- a/drivers/acpi/battery.c > +++ b/drivers/acpi/battery.c > @@ -34,6 +34,7 @@ > #include <linux/dmi.h> > #include <linux/slab.h> > #include <linux/suspend.h> > +#include <linux/delay.h> > #include <asm/unaligned.h> > > #ifdef CONFIG_ACPI_PROCFS_POWER > @@ -1119,7 +1120,7 @@ static struct dmi_system_id bat_dmi_table[] = { > > static int acpi_battery_add(struct acpi_device *device) > { > - int result = 0; > + int result = 0, retry = 5; > struct acpi_battery *battery = NULL; > > if (!device) > @@ -1135,7 +1136,16 @@ static int acpi_battery_add(struct acpi_device *device) > mutex_init(&battery->sysfs_lock); > if (acpi_has_method(battery->device->handle, "_BIX")) > set_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags); > + > +retry_get_info: > result = acpi_battery_update(battery, false); > + > + if (result && retry) { > + msleep(20); We're really going to wait up to 20 * 5 = 100ms for acpi_battery_update() to succeed? How are these the numbers that are determined to be optimal for probing? > + retry--; > + goto retry_get_info; > + } This most certainly could be rewritten as a for-loop and remove the ugly goto. > + > if (result) > goto fail; > #ifdef CONFIG_ACPI_PROCFS_POWER -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html