Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756055AbZCKNWX (ORCPT ); Wed, 11 Mar 2009 09:22:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754375AbZCKNWO (ORCPT ); Wed, 11 Mar 2009 09:22:14 -0400 Received: from mx1.auerswald.de ([212.185.163.234]:2143 "EHLO mail.auerswald.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754022AbZCKNWN convert rfc822-to-8bit (ORCPT ); Wed, 11 Mar 2009 09:22:13 -0400 From: Wolfgang =?iso-8859-15?q?M=FCes?= Organization: Auerswald GmbH & Co. KG To: Pierre Ossman Subject: [PATCH 3/7] mmc_spi: adjust for delayed data token response Date: Wed, 11 Mar 2009 14:21:56 +0100 User-Agent: KMail/1.9.10 Cc: "Andrew Morton" , "Matt Fleming" , "David Brownell" , "Mike Frysinger" , linux-kernel@vger.kernel.org MIME-Version: 1.0 Content-Disposition: inline Message-Id: <200903111421.56295.wolfgang.mues@auerswald.de> Content-Type: text/plain; charset="iso-8859-15" Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3133 Lines: 86 From: Wolfgang Muees o some cards are not able to send the data token in time, but miss the time frame for some bits(!). So synchronize to the start of the token. Signed-off-by: Wolfgang Muees --- This is one of a line of patches to enhance the usability of the mmc spi host port driver from "don't work with most SD cards" to "work with nearly all SD cards" (including those ugly cards with non-byte-aligned responses). diff -uprN 2_6_29_rc7_patch2_wait_16bytes_response/drivers/mmc/host/mmc_spi.c 2_6_29_rc7_patch3_delayed_data_response/drivers/mmc/host/mmc_spi.c --- 2_6_29_rc7_patch2_wait_16bytes_response/drivers/mmc/host/mmc_spi.c 2009-03-11 13:00:06.000000000 +0100 +++ 2_6_29_rc7_patch3_delayed_data_response/drivers/mmc/host/mmc_spi.c 2009-03-11 13:42:48.000000000 +0100 @@ -612,6 +612,7 @@ mmc_spi_writeblock(struct mmc_spi_host * struct spi_device *spi = host->spi; int status, i; struct scratch *scratch = host->data; + u32 pattern; if (host->mmc->use_spi_crc) scratch->crc_val = cpu_to_be16( @@ -639,8 +640,23 @@ mmc_spi_writeblock(struct mmc_spi_host * * doesn't necessarily tell whether the write operation succeeded; * it just says if the transmission was ok and whether *earlier* * writes succeeded; see the standard. - */ - switch (SPI_MMC_RESPONSE_CODE(scratch->status[0])) { + * + * In practice, there are (even modern SDHC-)Cards which need + * some bits to send the response, so we have to cope with this + * situation and check the response bit-by-bit. Arggh!!! + */ + pattern = scratch->status[0] << 24; + pattern |= scratch->status[1] << 16; + pattern |= scratch->status[2] << 8; + pattern |= scratch->status[3]; + + /* left-adjust to leading 0 bit */ + while (pattern & 0x80000000) + pattern <<= 1; + /* right-adjust for pattern matching. Code is in bit 4..0 now. */ + pattern >>= 27; + + switch (pattern) { case SPI_RESPONSE_ACCEPTED: status = 0; break; @@ -671,8 +687,8 @@ mmc_spi_writeblock(struct mmc_spi_host * /* Return when not busy. If we didn't collect that status yet, * we'll need some more I/O. */ - for (i = 1; i < sizeof(scratch->status); i++) { - if (scratch->status[i] != 0) + for (i = 4; i < sizeof(scratch->status); i++) { + if (scratch->status[i] & 0x01) return 0; } return mmc_spi_wait_unbusy(host, timeout); --- regards i. A. Wolfgang M?es -- Auerswald GmbH & Co. KG Hardware Development Telefon: +49 (0)5306 9219 0 Telefax: +49 (0)5306 9219 94 E-Mail: Wolfgang.Mues@Auerswald.de Web: http://www.auerswald.de ? -------------------------------------------------------------- Auerswald GmbH & Co. KG, Vor den Grash?fen 1, 38162 Cremlingen Registriert beim AG Braunschweig HRA 13289 p.h.G Auerswald Gesch?ftsf?hrungsges. mbH Registriert beim AG Braunschweig HRB 7463 Gesch?ftsf?hrer: Dipl-Ing. Gerhard Auerswald -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/