Commit 41875e38 authored by Sujit Reddy Thumma's avatar Sujit Reddy Thumma Committed by Chris Ball
Browse files

mmc: sdio: Fix SDIO 3.0 UHS-I initialization sequence 



According to UHS-I initialization sequence for SDIO 3.0 cards,
the host must set bit[24] (S18R) of OCR register during OCR
handshake to know whether the SDIO card is capable of doing
1.8V I/O.

Signed-off-by: default avatarSujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: default avatarSubhash Jadavani <subhashj@codeaurora.org>
Reviewed-by: default avatarJohan Rudholm <johan.rudholm@stericsson.com>
Reviewed-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: default avatarChris Ball <cjb@laptop.org>
parent 51aa66a5

drivers/mmc/core/sdio.c

+11 −11
Original line number Diff line number Diff line
@@ -157,10 +157,7 @@ static int sdio_read_cccr(struct mmc_card *card, u32 ocr) 
			if (ret)

				goto out;



			if (card->host->caps &

				(MMC_CAP_UHS_SDR12 | MMC_CAP_UHS_SDR25 |

				 MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR104 |

				 MMC_CAP_UHS_DDR50)) {

			if (mmc_host_uhs(card->host)) {

				if (data & SDIO_UHS_DDR50)

					card->sw_caps.sd3_bus_mode

						|= SD_MODE_UHS_DDR50;
@@ -478,8 +475,7 @@ static int sdio_set_bus_speed_mode(struct mmc_card *card) 
	 * If the host doesn't support any of the UHS-I modes, fallback on

	 * default speed.

	 */

	if (!(card->host->caps & (MMC_CAP_UHS_SDR12 | MMC_CAP_UHS_SDR25 |

	    MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR104 | MMC_CAP_UHS_DDR50)))

	if (!mmc_host_uhs(card->host))

		return 0;



	bus_speed = SDIO_SPEED_SDR12;
@@ -645,11 +641,7 @@ static int mmc_sdio_init_card(struct mmc_host *host, u32 ocr, 
	 * systems that claim 1.8v signalling in fact do not support

	 * it.

	 */

	if ((ocr & R4_18V_PRESENT) &&

		(host->caps &

			(MMC_CAP_UHS_SDR12 | MMC_CAP_UHS_SDR25 |

			 MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR104 |

			 MMC_CAP_UHS_DDR50))) {

	if ((ocr & R4_18V_PRESENT) && mmc_host_uhs(host)) {

		err = mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180,

				true);

		if (err) {
@@ -1022,6 +1014,10 @@ static int mmc_sdio_power_restore(struct mmc_host *host) 
		goto out;

	}



	if (mmc_host_uhs(host))

		/* to query card if 1.8V signalling is supported */

		host->ocr |= R4_18V_PRESENT;



	ret = mmc_sdio_init_card(host, host->ocr, host->card,

				mmc_card_keep_power(host));

	if (!ret && host->sdio_irqs)
@@ -1087,6 +1083,10 @@ int mmc_attach_sdio(struct mmc_host *host) 
	/*

	 * Detect and init the card.

	 */

	if (mmc_host_uhs(host))

		/* to query card if 1.8V signalling is supported */

		host->ocr |= R4_18V_PRESENT;



	err = mmc_sdio_init_card(host, host->ocr, NULL, 0);

	if (err) {

		if (err == -EAGAIN) {

include/linux/mmc/host.h

+8 −0
Original line number Diff line number Diff line
@@ -434,6 +434,14 @@ static inline int mmc_boot_partition_access(struct mmc_host *host) 
	return !(host->caps2 & MMC_CAP2_BOOTPART_NOACC);

}



static inline int mmc_host_uhs(struct mmc_host *host)

{

	return host->caps &

		(MMC_CAP_UHS_SDR12 | MMC_CAP_UHS_SDR25 |

		 MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR104 |

		 MMC_CAP_UHS_DDR50);

}



#ifdef CONFIG_MMC_CLKGATE

void mmc_host_clk_hold(struct mmc_host *host);

void mmc_host_clk_release(struct mmc_host *host);

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