From a01f3ccf845067de32189f8a8e85d22c381f93b9 Mon Sep 17 00:00:00 2001 From: Russell King - ARM Linux Date: Mon, 20 Jun 2011 20:10:28 +0100 Subject: [PATCH] mmc: block: improve error recovery from command channel errors Command channel errors fall into four classes: 1. The command was issued with the card in the wrong state 2. The command failed to be received by the card correctly 3. The cards response failed to be received by the host (CRC error) 4. The card failed to respond to the card For (1), in theory we should know that the card is in the correct state. However, a failed stop command (or other failure) may result in the card remaining in a data transfer state from the previous command. If we detect this condition, we try to recover by sending a stop command. For the initial commands (set block count and the read/write command) no data will have been transferred. All that we need deal with is retrying at this point. A failed stop command can be remedied as above. If we are unable to recover the card (eg, the card ignores our requests for status, or we don't recognise the error code) then we immediately fail the request. Signed-off-by: Russell King Acked-by: Linus Walleij Tested-by: Pawel Moll Signed-off-by: Chris Ball --- Reading git-format-patch failed