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

From: Lan Tianyu
Date: Mon Jan 06 2014 - 09:20:24 EST

On 01/06/2014 10:32 PM, Rafael J. Wysocki wrote:
On Monday, January 06, 2014 10:07:35 PM Lan Tianyu wrote:
On 01/04/2014 07:12 AM, Dmitry Torokhov wrote:
On Fri, Jan 03, 2014 at 05:01:11PM -0200, Leandro Dorileo wrote:
On Thu, Jan 02, 2014 at 03:37:57PM +0800, Lan Tianyu wrote:
The aml method _BIX of NEC LZ750/LS returns a broken package which
skip the first member "Revision" according ACPI 5.0 spec Table 10-234.

This patch is to add a quirk for this machine to skip member "Revision"
during parsing _BIX returned package.

Reported-and-tested-by: Francisco Castro <fcr@xxxxxxxxxxxxx>
Cc: 3.8+ <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Lan Tianyu <tianyu.lan@xxxxxxxxx>
drivers/acpi/battery.c | 28 +++++++++++++++++++++++++++-
1 file changed, 27 insertions(+), 1 deletion(-)

diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
index fbf1ace..3d64a87 100644
--- a/drivers/acpi/battery.c
+++ b/drivers/acpi/battery.c
@@ -62,6 +62,7 @@ MODULE_AUTHOR("Alexey Starikovskiy <astarikovskiy@xxxxxxx>");

+static int battery_bix_broken_package;
static unsigned int cache_time = 1000;
module_param(cache_time, uint, 0644);
MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
@@ -416,7 +417,12 @@ static int acpi_battery_get_info(struct acpi_battery *battery)
ACPI_EXCEPTION((AE_INFO, status, "Evaluating %s", name));
return -ENODEV;
- if (test_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags))
+ if (battery_bix_broken_package)
+ result = extract_package(battery, buffer.pointer,
+ extended_info_offsets + 1,
+ ARRAY_SIZE(extended_info_offsets) - 1);
+ else if (test_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags))
result = extract_package(battery, buffer.pointer,
@@ -754,6 +760,24 @@ static int battery_notify(struct notifier_block *nb,
return 0;

+static int battery_bix_package_quirk(const struct dmi_system_id *id)
+ battery_bix_broken_package = 1;
+ return 0;

Do you really need this callback? Why don't you just do:

if (dmi_check_system(bat_dmi_table))
battery_bix_broken_package = 1;

Callback would be useful if we were to print the DMI data of the match,
otherwise not so much.

Hi Leandro & Dmitry:
Thanks for your review. I select to callback mode as it's convenient to
add a new quirk for other machines if need. This Just likes what we have
done for the other ACPI drivers(E,G ac, processor_idle, video, thermal
and so on.).

We can switch to callbacks when we actually need them. Please keep things
as simple as reasonably possible.

Ok. I will update it.


Best Regards
Tianyu Lan
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