ARM: MXC: mxcmmc: work around a bug in the SDHC busy line handling
MX3 SoCs have a silicon bug which corrupts CRC calculation of
multi-block transfers when connected SDIO peripheral doesn't drive the
BUSY line as required by the specs.
One way to prevent this is to only allow 1-bit transfers.
Another way is playing tricks with the DMA engine, but this isn't
mainline yet. So for now, we live with the performance drawback of 1-bit
transfers until a nicer solution is found.
This patch introduces a new host controller callback 'init_card' which
is for now only called from mmc_sdio_init_card().
Signed-off-by: Daniel Mack <daniel@caiaq.de>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Volker Ernst <volker.ernst@txtr.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Michał Mirosław <mirqus@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
index 2dd4cfe..b9dee28 100644
--- a/drivers/mmc/core/sdio.c
+++ b/drivers/mmc/core/sdio.c
@@ -296,6 +296,12 @@
card->type = MMC_TYPE_SDIO;
/*
+ * Call the optional HC's init_card function to handle quirks.
+ */
+ if (host->ops->init_card)
+ host->ops->init_card(host, card);
+
+ /*
* For native busses: set card RCA and quit open drain mode.
*/
if (!powered_resume && !mmc_host_is_spi(host)) {