[patch 13/20] mmc: avoid getting CID on SDIO-only cards

[patch 13/20] mmc: avoid getting CID on SDIO-only cards

[akpm]

From: David Vrabel <david.vrabel@csr.com>

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>
Cc: Michal Miroslaw <mirq-linux@rere.qmqm.pl>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 drivers/mmc/core/sdio.c  |    8 +++++---
 include/linux/mmc/sdio.h |    2 ++
 2 files changed, 7 insertions(+), 3 deletions(-)

diff -puN drivers/mmc/core/sdio.c~mmc-avoid-getting-cid-on-sdio-only-cards drivers/mmc/core/sdio.c
--- a/drivers/mmc/core/sdio.c~mmc-avoid-getting-cid-on-sdio-only-cards
+++ a/drivers/mmc/core/sdio.c
@@ -362,11 +362,13 @@ static int mmc_sdio_init_card(struct mmc
 		goto err;
 	}
 
-	err = mmc_sd_get_cid(host, host->ocr & ocr, card->raw_cid);
-
-	if (!err) {
+	if (ocr & R4_MEMORY_PRESENT) {
 		card->type = MMC_TYPE_SD_COMBO;
 
+		err = mmc_sd_get_cid(host, host->ocr & ocr, card->raw_cid);
+		if (err)
+			goto remove;
+
 		if (oldcard && (oldcard->type != MMC_TYPE_SD_COMBO ||
 		    memcmp(card->raw_cid, oldcard->raw_cid, sizeof(card->raw_cid)) != 0)) {
 			mmc_remove_card(card);
diff -puN include/linux/mmc/sdio.h~mmc-avoid-getting-cid-on-sdio-only-cards include/linux/mmc/sdio.h
--- a/include/linux/mmc/sdio.h~mmc-avoid-getting-cid-on-sdio-only-cards
+++ a/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
_

Re: [patch 13/20] mmc: avoid getting CID on SDIO-only cards

[Andrew Morton]

On Thu, 19 Aug 2010 14:13:36 -0700
akpm@linux-foundation.org wrote:

> From: David Vrabel <david.vrabel@csr.com>
> 
> 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.
> 

argh, crap, sorry, please drop this one - Michal found a bug in it.