Re: [PATCH V2] ACPI/Battery: Add a _BIX quirk for NEC LZ750/LS

[Lan Tianyu <tianyu.lan@intel.com>]

On 01/15/2014 10:47 PM, Matthew Garrett wrote:
> On Wed, Jan 15, 2014 at 10:42:31PM +0800, Lan Tianyu wrote:
>> diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
>> index fbf1ace..e98fa83 100644
>> --- a/drivers/acpi/battery.c
>> +++ b/drivers/acpi/battery.c
>> @@ -770,7 +770,7 @@ static int acpi_battery_add(struct acpi_device *device)
>>          device->driver_data = battery;
>>          mutex_init(&battery->lock);
>>          mutex_init(&battery->sysfs_lock);
>> -       if (acpi_has_method(battery->device->handle, "_BIX"))
>> +       if (acpi_evaluate_object(device->handle, "_BIX", NULL, &buffer);)
>>                  set_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags);
>
> Doesn't acpi_evaluate_object() return 0 on success? I think:
>
> if (ACPI_SUCESS(acpi_evaluate_object(device->handle, "_BIX", NULL,
> &buffer))
>

Yes, Sorry for oops.

> But maybe we should check for existence first and give an FW_BUG message
> to indicate an invalid _BIX?

Yes, this is a good idea.

Another point, the acpi_evaluate_object should return different error 
code for these two cases(no _BIX and wrong size.). I wonder whether we 
can use the error code to determine it belong which case?
>


-- 
Best Regards
Tianyu Lan