From mboxrd@z Thu Jan 1 00:00:00 1970 From: stefan.xk.nilsson@stericsson.com (Stefan Nilsson XK) Date: Wed, 26 Oct 2011 10:45:27 +0200 Subject: [PATCH] mmc: mmci: Fix PIO read for small SDIO packets Message-ID: <1319618727-16969-1-git-send-email-stefan.xk.nilsson@stericsson.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Corrects a bug in MMCI host driver which silently causes small reads (< 4 bytes as only used in SDIO) from PL-18X to fail. Signed-off-by: Stefan Nilsson XK Signed-off-by: Ulf Hansson Acked-by: Linus Walleij --- drivers/mmc/host/mmci.c | 13 ++++++++++++- 1 files changed, 12 insertions(+), 1 deletions(-) diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c index 56e9a41..5c3a517 100644 --- a/drivers/mmc/host/mmci.c +++ b/drivers/mmc/host/mmci.c @@ -776,7 +776,18 @@ static int mmci_pio_read(struct mmci_host *host, char *buffer, unsigned int rema if (count <= 0) break; - readsl(base + MMCIFIFO, ptr, count >> 2); + /* + * SDIO especially may want to send something that is + * not divisible by 4 (as opposed to card sectors + * etc). Therefore make sure to to always read the last bytes + * while only doing full 32-bit reads towards the FIFO. + */ + if (count < 4) { + unsigned char buf[4]; + readsl(base + MMCIFIFO, buf, 1); + memcpy(ptr, buf, count); + } else + readsl(base + MMCIFIFO, ptr, count >> 2); ptr += count; remain -= count; -- 1.7.7