Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 24835611 authored by Heiner Kallweit's avatar Heiner Kallweit Committed by Ulf Hansson
Browse files

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: 79ed05e3 "mmc: meson-gx: add support for descriptor chain mode"
Signed-off-by: default avatarHeiner Kallweit <hkallweit1@gmail.com>
Tested-by: default avatarMartin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
parent 32c1431e

drivers/mmc/host/meson-gx-mmc.c

+9 −0
Original line number Diff line number Diff line
@@ -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) {