diff options
author | Heiner Kallweit <hkallweit1@gmail.com> | 2017-06-10 13:36:38 +0200 |
---|---|---|
committer | Ulf Hansson <ulf.hansson@linaro.org> | 2017-06-12 08:58:16 +0200 |
commit | 24835611a96e9b41ad57dd5024915106293be7e9 (patch) | |
tree | 02712b8f6363937cec0dd4ad6bcb9fba079a243d | |
parent | 32c1431eea4881a6b17bd7c639315010aeefa452 (diff) |
mmc: meson-gx: work around broken SDIO with certain WiFi chips
There have been reports about SDIO failing with certain WiFi chips in
descriptor chain mode. SD / eMMC are working fine.
So let's fall back to bounce buffer mode for command SD_IO_RW_EXTENDED.
This was reported to fix the error.
Fixes: 79ed05e329c3 "mmc: meson-gx: add support for descriptor chain mode"
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
-rw-r--r-- | drivers/mmc/host/meson-gx-mmc.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c index 1842ed341af1..de962c2d5e00 100644 --- a/drivers/mmc/host/meson-gx-mmc.c +++ b/drivers/mmc/host/meson-gx-mmc.c @@ -210,6 +210,15 @@ static void meson_mmc_get_transfer_mode(struct mmc_host *mmc, int i; bool use_desc_chain_mode = true; + /* + * Broken SDIO with AP6255-based WiFi on Khadas VIM Pro has been + * reported. For some strange reason this occurs in descriptor + * chain mode only. So let's fall back to bounce buffer mode + * for command SD_IO_RW_EXTENDED. + */ + if (mrq->cmd->opcode == SD_IO_RW_EXTENDED) + return; + for_each_sg(data->sg, sg, data->sg_len, i) /* check for 8 byte alignment */ if (sg->offset & 7) { |