Merge tag 'mmc-v4.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc
Pull MMC fix from Ulf Hansson:
"MMC meson-gx host: work around broken SDIO with certain WiFi chips"
* tag 'mmc-v4.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
mmc: meson-gx: work around broken SDIO with certain WiFi chips
diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c
index 1842ed3..de962c2 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) {
