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SubjectRe: [PATCH 5/7] mmc_spi: allow higher timeouts for SPI mode
Date
On Wednesday 11 March 2009, Wolfgang Mües wrote:
> From: Wolfgang Muees <wolfgang.mues@auerswald.de>
>
> o Some SD cards have very high timeouts in SPI mode.
> So adjust the timeouts from theory to practice.
>
> Signed-off-by: Wolfgang Muees <wolfgang.mues@auerswald.de>

Acked-by: David Brownell <dbrownell@users.sourceforge.net>


> ---
> This is one of a line of patches to enhance the usability of
> the mmc spi host port driver from "don't work with most SD cards"
> to "work with nearly all SD cards" (including those ugly cards
> with non-byte-aligned responses).
>
> diff -uprN 2_6_29_rc7_patch4_no_crc_on_CID_CSD/drivers/mmc/core/core.c 2_6_29_rc7_patch5_extra_spi_timeouts/drivers/mmc/core/core.c
> --- 2_6_29_rc7_patch4_no_crc_on_CID_CSD/drivers/mmc/core/core.c 2009-03-04 02:05:22.000000000 +0100
> +++ 2_6_29_rc7_patch5_extra_spi_timeouts/drivers/mmc/core/core.c 2009-03-10 12:06:16.000000000 +0100
> @@ -297,6 +297,21 @@ void mmc_set_data_timeout(struct mmc_dat
> data->timeout_clks = 0;
> }
> }
> + /*
> + * Some cards need very high timeouts if driven in SPI mode.
> + * The worst observed timeout was 900ms after writing a
> + * continuous stream of data until the internal logic
> + * overflowed.
> + */
> + if (mmc_host_is_spi(card->host)) {
> + if (data->flags & MMC_DATA_WRITE) {
> + if (data->timeout_ns < 1000000000)
> + data->timeout_ns = 1000000000; /* 1s */
> + } else {
> + if (data->timeout_ns < 100000000)
> + data->timeout_ns = 100000000; /* 100ms */
> + }
> + }
> }
> EXPORT_SYMBOL(mmc_set_data_timeout);
>
> ---
> regards
>
> i. A. Wolfgang Mües
> --
> Auerswald GmbH & Co. KG
> Hardware Development
> Telefon: +49 (0)5306 9219 0
> Telefax: +49 (0)5306 9219 94
> E-Mail: Wolfgang.Mues@Auerswald.de
> Web: http://www.auerswald.de
>  
> --------------------------------------------------------------
> Auerswald GmbH & Co. KG, Vor den Grashöfen 1, 38162 Cremlingen
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> Geschäftsführer: Dipl-Ing. Gerhard Auerswald
>
>



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