Commit 23e1b8c1 authored by Ulf Hansson's avatar Ulf Hansson
Browse files

mmc: core: Drop HS400 caps unless 8-bit bus is supported too 



When mmc_select_hs400es() tries to switch to the HS400 ES mode, it may bail
out early if the host doesn't support an 8-bit buswidth, as it's required
for the HS400 mode.

To improve the situation, let's instead drop the HS400 bits from the
capability field if the 8-bit bus isn't supported. In this way, we allow
the mmc initialization to continue by trying a lower speed mode.

Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20220303165151.129806-1-ulf.hansson@linaro.org
parent d6c9219c

drivers/mmc/core/host.c

+11 −2
Original line number Diff line number Diff line
@@ -590,11 +590,20 @@ EXPORT_SYMBOL(mmc_alloc_host); 


static int mmc_validate_host_caps(struct mmc_host *host)

{

	if (host->caps & MMC_CAP_SDIO_IRQ && !host->ops->enable_sdio_irq) {

		dev_warn(host->parent, "missing ->enable_sdio_irq() ops\n");

	struct device *dev = host->parent;

	u32 caps = host->caps, caps2 = host->caps2;



	if (caps & MMC_CAP_SDIO_IRQ && !host->ops->enable_sdio_irq) {

		dev_warn(dev, "missing ->enable_sdio_irq() ops\n");

		return -EINVAL;

	}



	if (caps2 & (MMC_CAP2_HS400_ES | MMC_CAP2_HS400) &&

	    !(caps & MMC_CAP_8_BIT_DATA)) {

		dev_warn(dev, "drop HS400 support since no 8-bit bus\n");

		host->caps2 = caps2 & ~MMC_CAP2_HS400_ES & ~MMC_CAP2_HS400;

	}



	return 0;

}

drivers/mmc/core/mmc.c

+0 −5
Original line number Diff line number Diff line
@@ -1355,11 +1355,6 @@ static int mmc_select_hs400es(struct mmc_card *card) 
	int err = -EINVAL;

	u8 val;



	if (!(host->caps & MMC_CAP_8_BIT_DATA)) {

		err = -ENOTSUPP;

		goto out_err;

	}



	if (card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS400_1_2V)

		err = mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120);