On Tuesday, June 17, 2014 03:09:54 PM Lan Tianyu wrote: > Some machines'(E,G Lenovo Z480) ECs are not stable during boot up > and causes battery driver fails to be loaded 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> > --- > Change since V2: > Change code style and add comment. > > drivers/acpi/battery.c | 16 ++++++++++++++-- > 1 file changed, 14 insertions(+), 2 deletions(-) > > diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c > index e48fc98..8ed93a3 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) > @@ -1135,9 +1136,20 @@ 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); > - result = acpi_battery_update(battery, false); > + > + /* > + * Some machines'(E,G Lenovo Z480) ECs are not stable > + * during boot up and this causes battery driver fails to be > + * probed due to failure of getting battery information > + * from EC sometimes. After several retries, the operation > + * may work. So add retry code here and 20ms sleep between > + * every retries. > + */ > + while ((result = acpi_battery_update(battery, false)) && retry--) > + msleep(20); > if (result) > goto fail; Why not to write this as for (;;) { result = acpi_battery_update(battery, false); if (!result) break; else if (!--retry) goto fail; msleep(20); } > + > #ifdef CONFIG_ACPI_PROCFS_POWER > result = acpi_battery_add_fs(device); > #endif > -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
