Re: [RFC] sdhci: use ios->clock to know when sdhci is idle

From: Pierre Tardy
Date: Sun Jan 02 2011 - 16:08:20 EST


> Not all SDIO cards will work properly if you try to gate them
> so we need a mechanism to selectively do this.
You are right..##??!! HW vendors that does not support standards...

AFAIK (was working on a sdio HW IP team before), the sdio clock is not
supposed to be taken as is for a system clock derivative especially
because it can stop between request.
SDIO IRQ are asynchronous when a command or data is not ongoing

> Any suggestions?
I would personally suggest white list from drivers. With a call to
mmc_host_allow_gate_card(struct mmc_card *card, bool allow)

see following patch..

Regards,
--
Pierre
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