From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michael Jones Subject: Re: [PATCH-v2.6.39] spi/omap_mcspi: Fix broken last word xfer Date: Tue, 22 Mar 2011 09:19:21 +0100 Message-ID: <4D885B89.8070608@matrix-vision.de> References: <1300717650-28953-1-git-send-email-jhnikula@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from mail2.matrix-vision.com ([85.214.244.251]:44052 "EHLO mail2.matrix-vision.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755122Ab1CVITX (ORCPT ); Tue, 22 Mar 2011 04:19:23 -0400 In-Reply-To: <1300717650-28953-1-git-send-email-jhnikula@gmail.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Jarkko Nikula Cc: spi-devel-general@lists.sourceforge.net, linux-omap@vger.kernel.org, Grant Likely On 03/21/2011 03:27 PM, Jarkko Nikula wrote: > Commit adef658 "spi/omap_mcspi: catch xfers of non-multiple SPI word size" > broke the transmission of last word in cases where access is multiple of > word size and word size is 16 or 32 bits. > > Fix this by replacing the test "c > (word_len>>3)" in do-while loops with > "c >= 'pointer increment size'". This ensures that the last word is > transmitted in above case and still allow to break the loop and prevent > variable c underflow in cases where word size != 'pointer increment size'. > > Signed-off-by: Jarkko Nikula > Cc: Michael Jones > --- > I noticed the issue with wl1251 WLAN driver on Nokia N900 using today's > vanilla head a44f99c7efdb88fa41128065c9a9445c19894e34. > --- > drivers/spi/omap2_mcspi.c | 6 +++--- > 1 files changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/spi/omap2_mcspi.c b/drivers/spi/omap2_mcspi.c > index 3a5ed06..6f86ba0 100644 > --- a/drivers/spi/omap2_mcspi.c > +++ b/drivers/spi/omap2_mcspi.c > @@ -517,7 +517,7 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) > dev_vdbg(&spi->dev, "read-%d %02x\n", > word_len, *(rx - 1)); > } > - } while (c > (word_len>>3)); > + } while (c); > } else if (word_len <= 16) { > u16 *rx; > const u16 *tx; > @@ -564,7 +564,7 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) > dev_vdbg(&spi->dev, "read-%d %04x\n", > word_len, *(rx - 1)); > } > - } while (c > (word_len>>3)); > + } while (c >= 2); > } else if (word_len <= 32) { > u32 *rx; > const u32 *tx; > @@ -611,7 +611,7 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) > dev_vdbg(&spi->dev, "read-%d %08x\n", > word_len, *(rx - 1)); > } > - } while (c > (word_len>>3)); > + } while (c >= 4); > } > > /* for TX_ONLY mode, be sure all words have shifted out */ Acked-by: Michael Jones MATRIX VISION GmbH, Talstrasse 16, DE-71570 Oppenweiler Registergericht: Amtsgericht Stuttgart, HRB 271090 Geschaeftsfuehrer: Gerhard Thullner, Werner Armingeon, Uwe Furtner