Received-SPF: pass (google.com: domain of linux-kernel+bounces-151102-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45d1:ec00::1 as permitted sender) client-ip=2604:1380:45d1:ec00::1;
Message-ID: <f8c0bdd4-58fb-45a5-a70e-cc97f176222e@collabora.com>
Date: Fri, 19 Apr 2024 09:26:41 +0200
Precedence: bulk
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH v3] power: supply: sbs-battery: Handle unsupported
 PROP_TIME_TO_EMPTY_NOW
To: =?UTF-8?B?TsOtY29sYXMgRi4gUi4gQS4gUHJhZG8=?= <nfraprado@collabora.com>,
 Sebastian Reichel <sre@kernel.org>
Cc: kernel@collabora.com, linux-pm@vger.kernel.org,
 linux-kernel@vger.kernel.org, Pin-yen Lin <treapking@chromium.org>,
 Hsin-Te Yuan <yuanhsinte@chromium.org>
References: <20240418-sbs-time-empty-now-error-v3-1-f286e29e3fca@collabora.com>
From: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Content-Language: en-US
In-Reply-To: <20240418-sbs-time-empty-now-error-v3-1-f286e29e3fca@collabora.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 8bit

Il 18/04/24 19:34, Nícolas F. R. A. Prado ha scritto:
> Despite the RunTimeToEmpty() (0x11) function being defined in the SBS
> specification as required, it seems that not all batteries implement it.
> On platforms with such batteries, reading the property will cause an
> error to be printed:
> 
> power_supply sbs-8-000b: driver failed to report `time_to_empty_now' property: -5
> 
> This not only pollutes the log, distracting from real problems on the
> device, but also prevents the uevent file from being read since it
> contains all properties, including the faulty one.
> 
> The following table summarizes the findings for a handful of platforms:
> 
> Platform                                Status  Manufacturer    Model
> ------------------------------------------------------------------------
> mt8186-corsola-steelix-sku131072        OK      BYD             L22B3PG0
> mt8195-cherry-tomato-r2                 NOT OK  PANASON         AP16L5J
> mt8192-asurada-spherion-r0              NOT OK  PANASON         AP15O5L
> mt8183-kukui-jacuzzi-juniper-sku16      NOT OK  LGC KT0         AP16L8J
> mt8173-elm-hana                         OK      Sunwoda         L18D3PG1
> sc7180-trogdor-lazor-limozeen-nots-r5   NOT OK  Murata          AP18C4K
> sc7180-trogdor-kingoftown               NOT OK  333-AC-0D-A     GG02047XL
> rk3399-gru-kevin                        OK      SDI             4352D51
> 
> Detect if this is one of the quirky batteries during presence update, so
> that hot-plugging works as expected, and if so report -ENODATA for
> POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW, which removes it from uevent and
> prevents throwing errors.
> 
> Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>

Nícolas, please, I think that sending this commit to stable for backporting
makes a lot of sense since you're actually fixing laptops (that does not
really require a Fixes tag) that are supported upstream since .. lots of time
ago.

In any case, this LGTM.

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>