Re: [PATCH] mmc: omap_hsmmc: set dto to 14 for all devices

[Chris Ball <cjb@laptop.org>]

Hi Chase,

On Thu, Mar 01 2012, Chase Maupin wrote:
> * With certain SD cards timeouts like the following have been seen
>   due to an improper calculation of the dto value:
>     mmcblk0: error -110 transferring data, sector 4126233, nr 8,
>     card status 0xc00
> * By removing the dto calculation and setting the timeout value
>   to the maximum specified by the SD card specification part A2
>   section 2.2.15 these timeouts can be avoided.
> * This change has been used by beagleboard users as well as the
>   Texas Instruments SDK without a negative impact.
> * There are multiple discussion threads about this but the most
>   relevant ones are:
>     * http://talk.maemo.org/showthread.php?p=1000707#post1000707
>     * http://www.mail-archive.com/linux-omap@vger.kernel.org/msg42213.html
> * Original proposal for this fix was done by Sukumar Ghoral of
>   Texas Instruments
>
> * Tested using a Texas Instruments AM335x EVM
>
> Signed-off-by: Chase Maupin <Chase.Maupin@ti.com>

Thanks, I've pushed this to mmc-next for 3.4.  (With a trivial
indentation fix, below.)

diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
index 82b400793..9d4ce1c 100644
--- a/drivers/mmc/host/omap_hsmmc.c
+++ b/drivers/mmc/host/omap_hsmmc.c
@@ -1360,7 +1360,7 @@ static void set_data_timeout(struct omap_hsmmc_host *host)
 	if (clkd == 0)
 		clkd = 1;
 
-    /* Use the maximum timeout value allowed in the standard of 14 or 0xE */
+	/* Use the maximum timeout value allowed in the standard of 14 or 0xE */
 	dto = 14;
 
 	reg &= ~DTO_MASK;


- Chris.
-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child