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Date:   Wed, 3 Nov 2021 17:17:56 +0000
From:   Daniel Thompson <daniel.thompson@linaro.org>
To:     Hans de Goede <hdegoede@redhat.com>
Cc:     Lee Jones <lee.jones@linaro.org>,
        Jingoo Han <jingoohan1@gmail.com>,
        Tsuchiya Yuto <kitakar@gmail.com>,
        dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 3/3] backlight: lp855x: Add support ACPI enumeration
Message-ID: <20211103171756.wxthncse2f4syeiz@maple.lan>
References: <20211102225504.18920-1-hdegoede@redhat.com>
 <20211102225504.18920-3-hdegoede@redhat.com>
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On Tue, Nov 02, 2021 at 11:55:04PM +0100, Hans de Goede wrote:
> The Xiaomi Mi Pad 2 tablet uses an ACPI enumerated LP8556 backlight
> controller for its LCD-panel, with a Xiaomi specific ACPI HID of
> "XMCC0001", add support for this.
> 
> Note the new "if (id)" check also fixes a NULL pointer deref when a user
> tries to manually bind the driver from sysfs.
> 
> When CONFIG_ACPI is disabled acpi_match_device() will always return NULL,
> so the lp855x_parse_acpi() call will get optimized away.
> 
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>

Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>


Daniel.