Re: [PATCH 2/2] platform/loongarch: laptop: Support backlight power control

[WANG Xuerui]

On 6/3/25 12:16, Huacai Chen wrote:
> On Sat, May 31, 2025 at 7:39 PM Yao Zi <ziyao@xxxxxxxxxxx> wrote:
> > loongson_laptop_turn_{on,off}_backlight() are designed for controlling
> > power of the backlight, but they aren't really used in the driver
> > previously.
> >
> > Unify these two functions since they only differ in arguments passed to
> > ACPI method, and wire up loongson_laptop_backlight_update() to update
> > power state of the backlight as well. Tested on TongFang L860-T2 3A5000
> > laptop.
> >
> > Signed-off-by: Yao Zi <ziyao@xxxxxxxxxxx>
> > ---
> >   drivers/platform/loongarch/loongson-laptop.c | 53 +++++++-------------
> >   1 file changed, 19 insertions(+), 34 deletions(-)
> >
> > [snip]
> >
> > -int loongson_laptop_turn_on_backlight(void)
> > -{
> > -       int status;
> > -       union acpi_object arg0 = { ACPI_TYPE_INTEGER };
> > -       struct acpi_object_list args = { 1, &arg0 };
> > -
> > -       arg0.integer.value = 1;
> > -       status = acpi_evaluate_object(NULL, "\\BLSW", &args, NULL);
> > -       if (ACPI_FAILURE(status)) {
> > -               pr_info("Loongson lvds error: 0x%x\n", status);
> > -               return -ENODEV;
> > -       }
> > -
> > -       return 0;
> > -}
> > -
> > -int loongson_laptop_turn_off_backlight(void)
> > -{
> > -       int status;
> > -       union acpi_object arg0 = { ACPI_TYPE_INTEGER };
> > -       struct acpi_object_list args = { 1, &arg0 };
> > -
> > -       arg0.integer.value = 0;
> > -       status = acpi_evaluate_object(NULL, "\\BLSW", &args, NULL);
> > -       if (ACPI_FAILURE(status)) {
> > -               pr_info("Loongson lvds error: 0x%x\n", status);
> > -               return -ENODEV;
> > -       }
> > -
> > -       return 0;
> > -}
> I prefer to keep them, in downstream kernels there are users of them,
> I don't want to add them back if one day those users are upstream.

Then these symbols should be properly EXPORT_SYMBOL_GPL marked?

--
WANG "xen0n" Xuerui

Linux/LoongArch mailing list: https://lore.kernel.org/loongarch/