linux-kernel - Re: [PATCH v1] battery: Add the ThinkPad battery status quirk

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 10 Apr 2018 12:58:41 +0200
From:   Sebastian Reichel <sre@...nel.org>
To:     Ognjen Galic <smclt30p@...il.com>
Cc:     "Rafael J. Wysocki" <rjw@...ysocki.net>,
        Len Brown <lenb@...nel.org>, linux-acpi@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH v1] battery: Add the ThinkPad battery status quirk

Hi,

On Tue, Apr 10, 2018 at 11:06:43AM +0200, Ognjen Galic wrote:
> The EC/ACPI firmware on Lenovo ThinkPads used to report a status
> of "Unknown" when the battery is between the charge start and charge
> stop thresholds. On Windows, it reports "Not Charging" so the quirk
> has been added to fix the "Unknown" state.
> 
> The chosen new state when the battery is not charging is "Fully Charged"
> because a status of "Not Charging" breaks almost all applications in
> userspace that depend on upower, because upower in itself can't handle
> a state of "Not Charging", defaulting to "Unknown".
> 
> When we report "Fully Charged" instead of "Unknown", the userspace handles
> everything just fine, displaying for example: "Fully Charged, 59%" in Xfce.

This probably breaks dual-battery Thinkpads, that charges batteries
alternating (so one of them is "not charging" without being "fully
charged"). The correct fix is to teach upower the "not charging"
state. It exists since the existance of the power supply kernel API,
so missing support is a bug in UPower.

-- Sebastian

> This is a re-write of: https://patchwork.kernel.org/patch/10205359/
> 
> Signed-off-by: Ognjen Galic <smclt30p@...il.com>
> ---
>  drivers/acpi/battery.c | 19 ++++++++++++++++++-
>  1 file changed, 18 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
> index bdb24d63..cb4457a7 100644
> --- a/drivers/acpi/battery.c
> +++ b/drivers/acpi/battery.c
> @@ -74,6 +74,7 @@ static async_cookie_t async_cookie;
>  static bool battery_driver_registered;
>  static int battery_bix_broken_package;
>  static int battery_notification_delay_ms;
> +static int battery_quirk_thinkpad_full;
>  static unsigned int cache_time = 1000;
>  module_param(cache_time, uint, 0644);
>  MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
> @@ -233,7 +234,8 @@ static int acpi_battery_get_property(struct power_supply *psy,
>  			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
>  		else if (battery->state & ACPI_BATTERY_STATE_CHARGING)
>  			val->intval = POWER_SUPPLY_STATUS_CHARGING;
> -		else if (acpi_battery_is_charged(battery))
> +		else if (acpi_battery_is_charged(battery) ||
> +				battery_quirk_thinkpad_full)
>  			val->intval = POWER_SUPPLY_STATUS_FULL;
>  		else
>  			val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
> @@ -1332,6 +1334,13 @@ battery_notification_delay_quirk(const struct dmi_system_id *d)
>  	return 0;
>  }
>  
> +static int __init
> +battery_thinkpad_full_charged_quirk(const struct dmi_system_id *d)
> +{
> +	battery_quirk_thinkpad_full = 1;
> +	return 0;
> +}
> +
>  static const struct dmi_system_id bat_dmi_table[] __initconst = {
>  	{
>  		.callback = battery_bix_broken_package_quirk,
> @@ -1349,6 +1358,14 @@ static const struct dmi_system_id bat_dmi_table[] __initconst = {
>  			DMI_MATCH(DMI_PRODUCT_NAME, "Aspire V5-573G"),
>  		},
>  	},
> +	{
> +		.callback = battery_thinkpad_full_charged_quirk,
> +		.ident = "Lenovo ThinkPad",
> +		.matches = {
> +			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
> +			DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad"),
> +		},
> +	},
>  	{},
>  };
>  
> -- 
> 2.15.1
> 

Download attachment "signature.asc" of type "application/pgp-signature" (834 bytes)