Commit 44669034 authored by Stefan Nilsson XK's avatar Stefan Nilsson XK Committed by Chris Ball
Browse files

mmc: core: Set correct bus mode before card init 



Earlier all cards where initiated with bus mode set as OPENDRAIN, and then
later switched to PUSHPULL. According to the MMC/SD/SDIO specifications
only MMC cards use OPENDRAIN during init. For both SD and SDIO the bus
mode shall be PUSHPULL before attempting to init the card.

The consequence of having incorrect bus mode can lead to not being able
to detect the card. Therefore the default behavior have now been changed
to PUSHPULL in mmc_power_up, and will only be temporarily switched when
trying to attach or init a MMC card.

Signed-off-by: default avatarStefan Nilsson XK <stefan.xk.nilsson@stericsson.com>
Signed-off-by: default avatarUlf HANSSON <ulf.hansson@stericsson.com>
Acked-by: default avatarLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: default avatarChris Ball <cjb@laptop.org>
parent 9a0da648

drivers/mmc/core/core.c

+3 −5
Original line number Diff line number Diff line
@@ -1160,13 +1160,11 @@ static void mmc_power_up(struct mmc_host *host) 
		bit = fls(host->ocr_avail) - 1;



	host->ios.vdd = bit;

	if (mmc_host_is_spi(host)) {

	if (mmc_host_is_spi(host))

		host->ios.chip_select = MMC_CS_HIGH;

		host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;

	} else {

	else

		host->ios.chip_select = MMC_CS_DONTCARE;

		host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;

	}

	host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;

	host->ios.power_mode = MMC_POWER_UP;

	host->ios.bus_width = MMC_BUS_WIDTH_1;

	host->ios.timing = MMC_TIMING_LEGACY;

drivers/mmc/core/mmc.c

+8 −0
Original line number Diff line number Diff line
@@ -548,6 +548,10 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr, 
	BUG_ON(!host);

	WARN_ON(!host->claimed);



	/* Set correct bus mode for MMC before attempting init */

	if (!mmc_host_is_spi(host))

		mmc_set_bus_mode(host, MMC_BUSMODE_OPENDRAIN);



	/*

	 * Since we're changing the OCR value, we seem to

	 * need to tell some cards to go back to the idle
@@ -1022,6 +1026,10 @@ int mmc_attach_mmc(struct mmc_host *host) 
	BUG_ON(!host);

	WARN_ON(!host->claimed);



	/* Set correct bus mode for MMC before attempting attach */

	if (!mmc_host_is_spi(host))

		mmc_set_bus_mode(host, MMC_BUSMODE_OPENDRAIN);



	err = mmc_send_op_cond(host, 0, &ocr);

	if (err)

		return err;

drivers/mmc/core/sd.c

+0 −2
Original line number Diff line number Diff line
@@ -929,8 +929,6 @@ static int mmc_sd_init_card(struct mmc_host *host, u32 ocr, 
		err = mmc_send_relative_addr(host, &card->rca);

		if (err)

			return err;



		mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);

	}



	if (!oldcard) {

drivers/mmc/core/sdio.c

+0 −2
Original line number Diff line number Diff line
@@ -408,8 +408,6 @@ static int mmc_sdio_init_card(struct mmc_host *host, u32 ocr, 
		 */

		if (oldcard)

			oldcard->rca = card->rca;



		mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);

	}



	/*

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