mmc: rtsx_usb_sdmmc: suppress false CD after init timeout

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Some Realtek USB SD readers with a tray keep raw SD_CD asserted
when an empty tray is inserted. The MMC core then repeatedly tries to
initialize non-existent media, sees command timeouts, calls ->get_cd()
again, and starts the same detect cycle over.

Do not qualify media by open-coding MMC commands in ->get_cd().
Instead, let the normal MMC rescan path probe the card. If an
initialization command times out before a card has been attached,
suppress the raw SD_CD signal so the host can settle and the USB
parent can autosuspend.

Clear the suppression only when raw SD_CD drops. On the affected tray
reader, changing media requires removing and reinserting the tray, so
a low CD transition is the signal that a new insertion attempt can be
trusted again.

Signed-off-by: Sean Rhodes <sean@starlabs.systems>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ulf Hansson <ulfh@kernel.org>

...

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Sean Rhodes 2026-07-06 16:40:44 +01:00 • committed by Ulf Hansson

parent 483c948324

commit 7185b6d33b

1 changed files with 12 additions and 1 deletions

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drivers/mmc/host/rtsx_usb_sdmmc.c

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