linux-kernel - Re: [PATCH] platform/x86: fujitsu-laptop: Fix radio LED detection

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Date:   Fri, 27 Oct 2017 19:49:55 +0300
From:   Andy Shevchenko <andy.shevchenko@...il.com>
To:     Michał Kępień <kernel@...pniu.pl>
Cc:     Jonathan Woithe <jwoithe@...t42.net>,
        Darren Hart <dvhart@...radead.org>,
        Andy Shevchenko <andy@...radead.org>, Harvey <harv@....de>,
        Platform Driver <platform-driver-x86@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] platform/x86: fujitsu-laptop: Fix radio LED detection

On Wed, Oct 25, 2017 at 7:29 AM, Michał Kępień <kernel@...pniu.pl> wrote:
> Radio LED detection method implemented in commit 4f62568c1fcf
> ("fujitsu-laptop: Support radio LED") turned out to be incorrect as it
> causes a radio LED to be erroneously detected on a Fujitsu Lifebook E751
> which has a slide switch (and thus no radio LED).  Use bit 17 of
> flags_supported (the value returned by method S000 of ACPI device
> FUJ02E3) to determine whether a radio LED is present as it seems to be a
> more reliable indicator, based on comparing DSDT tables of four Fujitsu
> Lifebook models (E744, E751, S7110, S8420).
>

Pushed to my review and testing queue, thanks!

> Reported-by: Heinrich Siebmanns <harv@....de>
> Signed-off-by: Michał Kępień <kernel@...pniu.pl>
> ---
> I do not have a Fujitsu laptop with a radio LED for testing, so I was
> only able to check that this patch still does not cause a radio LED to
> be detected on a Lifebook S7020.
>
> Harvey, could you please try this patch on your Lifebook E751 and see
> whether the log messages you reported disappear?  I will be happy to
> assist you off-list in case you need help with it.
>
>  drivers/platform/x86/fujitsu-laptop.c | 14 +++++++++-----
>  1 file changed, 9 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/platform/x86/fujitsu-laptop.c b/drivers/platform/x86/fujitsu-laptop.c
> index 56a8195096a2..2cfbd3fa5136 100644
> --- a/drivers/platform/x86/fujitsu-laptop.c
> +++ b/drivers/platform/x86/fujitsu-laptop.c
> @@ -691,6 +691,7 @@ static enum led_brightness eco_led_get(struct led_classdev *cdev)
>
>  static int acpi_fujitsu_laptop_leds_register(struct acpi_device *device)
>  {
> +       struct fujitsu_laptop *priv = acpi_driver_data(device);
>         struct led_classdev *led;
>         int result;
>
> @@ -724,12 +725,15 @@ static int acpi_fujitsu_laptop_leds_register(struct acpi_device *device)
>         }
>
>         /*
> -        * BTNI bit 24 seems to indicate the presence of a radio toggle
> -        * button in place of a slide switch, and all such machines appear
> -        * to also have an RF LED.  Therefore use bit 24 as an indicator
> -        * that an RF LED is present.
> +        * Some Fujitsu laptops have a radio toggle button in place of a slide
> +        * switch and all such machines appear to also have an RF LED.  Based on
> +        * comparing DSDT tables of four Fujitsu Lifebook models (E744, E751,
> +        * S7110, S8420; the first one has a radio toggle button, the other
> +        * three have slide switches), bit 17 of flags_supported (the value
> +        * returned by method S000 of ACPI device FUJ02E3) seems to indicate
> +        * whether given model has a radio toggle button.
>          */
> -       if (call_fext_func(device, FUNC_BUTTONS, 0x0, 0x0, 0x0) & BIT(24)) {
> +       if (priv->flags_supported & BIT(17)) {
>                 led = devm_kzalloc(&device->dev, sizeof(*led), GFP_KERNEL);
>                 if (!led)
>                         return -ENOMEM;
> --
> 2.14.2
>



-- 
With Best Regards,
Andy Shevchenko