[PATCH 4/4] mmc: mmci: Fix incorrect handling of HW flow control for SDIO
Stefan Nilsson XK
stefan.xk.nilsson at stericsson.com
Mon Oct 3 03:31:14 EDT 2011
Hi Russel,
On 10/01/2011 06:12 PM, Russell King - ARM Linux wrote:
> Shouldn't this also re-enable the ST hardware flow control for non-SDIO
> cards?
I do not think that is needed. Hardware flow control is turned on per
default for all cards thanks to the .clkreg member of the variant struct:
mmci_set_clkreg():
clk |= variant->clkreg_enable;
where
static struct variant_data variant_ux500v2 = {
.clkreg_enable = MCI_ST_UX500_HWFCEN,
This means that HWFC will be on for all cards. This patch only disables
it for SDIO cards (thanks to the mmc_card_sdio()-check) during
problematic transfers (HW peculiarity), and then re-enables it again for
SDIO cards during "normal" transfers. So the HWFC state for non-SDIO
cards should not be touched I think.
Best Regards
Stefan Nilsson
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