Subject: Re: [PATCH 3/4] sdhci-of: Fix high-speed cards recognition

From: David Vrabel <[email-masked]>
Date: Fri, 07 Aug 2009 18:08:59 +0100

Anton Vorontsov wrote:
> eSDHC fails to recognize some SDHS cards, throwing timeout errors:
> 
>   mmc0: error -110 whilst initialising SD card
> 
> That's because we calculate timeout value in a wrong way: on eSDHC
> hosts the timeout clock is derivied from the SD clock, which is set
> dynamically.

I've seen an reference design for an SDHC controller do this also.

> +/* Controller has dynamic timeout clock management */
> +#define SDHCI_QUIRK_DYNAMIC_TIMEOUT_CLOCK		(1<<24)

This comment and define would be better if it matched terms used in the
spec.  Suggest:

/* Controller uses SDCLK instead of TMCLK for data timeouts. */
#define SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK  (1 << 24)

David
-- 
David Vrabel, Senior Software Engineer, Drivers
CSR, Churchill House, Cambridge Business Park,  Tel: +44 (0)1223 692562
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