mmc: avoid getting CID on SDIO-only cards

The introduction of support for SD combo cards breaks the initialization
of all CSR SDIO chips.  The GO_IDLE (CMD0) in mmc_sd_get_cid() causes CSR
chips to be reset (this is non-standard behavior).

When initializing an SDIO card check for a combo card by using the memory
present bit in the R4 response to IO_SEND_OP_COND (CMD5).  This avoids the
call to mmc_sd_get_cid() on an SDIO-only card.

Signed-off-by: David Vrabel <david.vrabel@csr.com>
Acked-by: Michal Mirolaw <mirq-linux@rere.qmqm.pl>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/linux/mmc/sdio.h b/include/linux/mmc/sdio.h
index 329a8faa6e37..245cdacee544 100644
--- a/include/linux/mmc/sdio.h
+++ b/include/linux/mmc/sdio.h
@@ -38,6 +38,8 @@
  *      [8:0] Byte/block count
  */
 
+#define R4_MEMORY_PRESENT (1 << 27)
+
 /*
   SDIO status in R5
   Type