From 30652aa36b58d57fcc1a0acce51e391bbb6edf5e Mon Sep 17 00:00:00 2001 From: Olof Johansson Date: Sat, 1 Jan 2011 18:37:32 -0600 Subject: [PATCH] mmc: sdhci: add quirk for max len ADMA descriptors Some controllers misparse segment length 0 as being 0, not 65536. Add a quirk to deal with it. Signed-off-by: Olof Johansson Reviewed-by: Chris Ball Signed-off-by: Chris Ball --- drivers/mmc/host/sdhci.c | 10 +++++++--- include/linux/mmc/sdhci.h | 2 ++ 2 files changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index d5febe584b05..9e15f41f87be 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -1949,10 +1949,14 @@ int sdhci_add_host(struct sdhci_host *host) * of bytes. When doing hardware scatter/gather, each entry cannot * be larger than 64 KiB though. */ - if (host->flags & SDHCI_USE_ADMA) - mmc->max_seg_size = 65536; - else + if (host->flags & SDHCI_USE_ADMA) { + if (host->quirks & SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC) + mmc->max_seg_size = 65535; + else + mmc->max_seg_size = 65536; + } else { mmc->max_seg_size = mmc->max_req_size; + } /* * Maximum block size. This varies from controller to controller and diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h index 0d953f513d81..83bd9f76709a 100644 --- a/include/linux/mmc/sdhci.h +++ b/include/linux/mmc/sdhci.h @@ -83,6 +83,8 @@ struct sdhci_host { #define SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12 (1<<28) /* Controller doesn't have HISPD bit field in HI-SPEED SD card */ #define SDHCI_QUIRK_NO_HISPD_BIT (1<<29) +/* Controller treats ADMA descriptors with length 0000h incorrectly */ +#define SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC (1<<30) int irq; /* Device IRQ */ void __iomem *ioaddr; /* Mapped address */ -- 2.20.1