Hans de Goede 22d04790d6 mmc: sdhci-acpi: Add quirk to enable pull-up on the card-detect GPIO on Asus T100TA
commit 431946c0f640c93421439a6c928efb3152c035a4 upstream.

The card-detect GPIO for the microSD slot on Asus T100TA / T100TAM models
stopped working under Linux after commit 6fd03f024828 ("gpiolib: acpi:
support bias pull disable").

The GPIO in question is connected to a mechanical switch in the slot
which shorts the pin to GND when a card is inserted.

The GPIO pin correctly gets configured with a 20K pull-up by the BIOS,
but there is a bug in the DSDT where the GpioInt for the card-detect is
configured with a PullNone setting:

    GpioInt (Edge, ActiveBoth, SharedAndWake, PullNone, 0x2710,
        "\\_SB.GPO0", 0x00, ResourceConsumer, ,
        )
        {   // Pin list
        0x0026
        }

Linux now actually honors the PullNone setting and disables the 20K pull-up
configured by the BIOS.

Add a new DMI_QUIRK_SD_CD_ENABLE_PULL_UP quirk which when set calls
mmc_gpiod_set_cd_config() to re-enable the pull-up and set this for
the Asus T100TA models to fix this.

Fixes: 6fd03f024828 ("gpiolib: acpi: support bias pull disable")
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240410191639.526324-7-hdegoede@redhat.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-16 13:47:37 +02:00
2023-08-31 12:20:12 -07:00
2022-09-28 09:02:20 +02:00
2022-10-10 12:00:45 -07:00
2024-06-12 11:13:03 +02:00

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