This patch fixs eMMC-Access on mt7622/Bpi-64. Before we got these Errors on mounting eMMC ion R64: [ 48.664925] blk_update_request: I/O error, dev mmcblk0, sector 204800 op 0x1:(WRITE) flags 0x800 phys_seg 1 prio class 0 [ 48.676019] Buffer I/O error on dev mmcblk0p1, logical block 0, lost sync page write

This patch adds a optional reset management for msdc. Sometimes the bootloader does not bring msdc register to default state, so need reset the msdc controller.

Cc: stable@vger.kernel.org # v5.4+ Fixes: 966580ad236e ("mmc: mediatek: add support for MT7622 SoC") Signed-off-by: Wenbin Mei wenbin.mei@mediatek.com Reviewed-by: Philipp Zabel p.zabel@pengutronix.de Tested-by: Frank Wunderlich frank-w@public-files.de --- drivers/mmc/host/mtk-sd.c | 13 +++++++++++++ 1 file changed, 13 insertions(+)

diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c index 39e7fc54c438..fc97d5bf3a20 100644 --- a/drivers/mmc/host/mtk-sd.c +++ b/drivers/mmc/host/mtk-sd.c @@ -22,6 +22,7 @@ #include <linux/slab.h> #include <linux/spinlock.h> #include <linux/interrupt.h> +#include <linux/reset.h>

#include <linux/mmc/card.h> #include <linux/mmc/core.h> @@ -434,6 +435,7 @@ struct msdc_host { struct msdc_save_para save_para; /* used when gate HCLK */ struct msdc_tune_para def_tune_para; /* default tune setting */ struct msdc_tune_para saved_tune_para; /* tune result of CMD21/CMD19 */ + struct reset_control *reset; };

static const struct mtk_mmc_compatible mt8135_compat = { @@ -1516,6 +1518,12 @@ static void msdc_init_hw(struct msdc_host *host) u32 val; u32 tune_reg = host->dev_comp->pad_tune_reg;

+ if (host->reset) { + reset_control_assert(host->reset); + usleep_range(10, 50); + reset_control_deassert(host->reset); + } + /* Configure to MMC/SD mode, clock free running */ sdr_set_bits(host->base + MSDC_CFG, MSDC_CFG_MODE | MSDC_CFG_CKPDN);

@@ -2273,6 +2281,11 @@ static int msdc_drv_probe(struct platform_device *pdev) if (IS_ERR(host->src_clk_cg)) host->src_clk_cg = NULL;

+ host->reset = devm_reset_control_get_optional_exclusive(&pdev->dev, + "hrst"); + if (IS_ERR(host->reset)) + return PTR_ERR(host->reset); + host->irq = platform_get_irq(pdev, 0); if (host->irq < 0) { ret = -EINVAL;