Commit 20b92a30 authored by Kevin Liu's avatar Kevin Liu Committed by Chris Ball
Browse files

mmc: sdhci: update signal voltage switch code 



The protocol related code is moved to core stack. So update the host
driver accordingly.

Signed-off-by: default avatarKevin Liu <kliu5@marvell.com>
Tested-by: default avatarTim Wang <wangtt@marvell.com>
Signed-off-by: default avatarChris Ball <cjb@laptop.org>
parent 0797e5f1

drivers/mmc/host/sdhci.c

+78 −114
Original line number Diff line number Diff line
@@ -1615,11 +1615,23 @@ static void sdhci_enable_sdio_irq(struct mmc_host *mmc, int enable) 
	spin_unlock_irqrestore(&host->lock, flags);

}



static int sdhci_do_3_3v_signal_voltage_switch(struct sdhci_host *host,

						u16 ctrl)

static int sdhci_do_start_signal_voltage_switch(struct sdhci_host *host,

						int signal_voltage)

{

	u16 ctrl;

	int ret;



	/*

	 * Signal Voltage Switching is only applicable for Host Controllers

	 * v3.00 and above.

	 */

	if (host->version < SDHCI_SPEC_300)

		return 0;



	ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);



	switch (signal_voltage) {

	case MMC_SIGNAL_VOLTAGE_330:

		/* Set 1.8V Signal Enable in the Host Control2 register to 0 */

		ctrl &= ~SDHCI_CTRL_VDD_180;

		sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);
@@ -1643,117 +1655,55 @@ static int sdhci_do_3_3v_signal_voltage_switch(struct sdhci_host *host, 
		pr_warning("%s: 3.3V regulator output did not became stable\n",

				mmc_hostname(host->mmc));



		return -EAGAIN;

	case MMC_SIGNAL_VOLTAGE_180:

		if (host->vqmmc) {

			ret = regulator_set_voltage(host->vqmmc,

					1700000, 1950000);

			if (ret) {

				pr_warning("%s: Switching to 1.8V signalling voltage "

						" failed\n", mmc_hostname(host->mmc));

				return -EIO;

			}

		}



static int sdhci_do_1_8v_signal_voltage_switch(struct sdhci_host *host,

						u16 ctrl)

{

	u8 pwr;

	u16 clk;

	u32 present_state;

	int ret;



	/* Stop SDCLK */

	clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);

	clk &= ~SDHCI_CLOCK_CARD_EN;

	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);



	/* Check whether DAT[3:0] is 0000 */

	present_state = sdhci_readl(host, SDHCI_PRESENT_STATE);

	if (!((present_state & SDHCI_DATA_LVL_MASK) >>

	       SDHCI_DATA_LVL_SHIFT)) {

		/*

		 * Enable 1.8V Signal Enable in the Host Control2

		 * register

		 */

		if (host->vqmmc)

			ret = regulator_set_voltage(host->vqmmc,

				1700000, 1950000);

		else

			ret = 0;



		if (!ret) {

		ctrl |= SDHCI_CTRL_VDD_180;

		sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);



		/* Wait for 5ms */

		usleep_range(5000, 5500);



		/* 1.8V regulator output should be stable within 5 ms */

		ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);

			if (ctrl & SDHCI_CTRL_VDD_180) {

				/* Provide SDCLK again and wait for 1ms */

				clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);

				clk |= SDHCI_CLOCK_CARD_EN;

				sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);

				usleep_range(1000, 1500);



				/*

				 * If DAT[3:0] level is 1111b, then the card

				 * was successfully switched to 1.8V signaling.

				 */

				present_state = sdhci_readl(host,

							SDHCI_PRESENT_STATE);

				if ((present_state & SDHCI_DATA_LVL_MASK) ==

				     SDHCI_DATA_LVL_MASK)

		if (ctrl & SDHCI_CTRL_VDD_180)

			return 0;

			}

		}

	}



	/*

	 * If we are here, that means the switch to 1.8V signaling

	 * failed. We power cycle the card, and retry initialization

	 * sequence by setting S18R to 0.

	 */

	pwr = sdhci_readb(host, SDHCI_POWER_CONTROL);

	pwr &= ~SDHCI_POWER_ON;

	sdhci_writeb(host, pwr, SDHCI_POWER_CONTROL);

	if (host->vmmc)

		regulator_disable(host->vmmc);



	/* Wait for 1ms as per the spec */

	usleep_range(1000, 1500);

	pwr |= SDHCI_POWER_ON;

	sdhci_writeb(host, pwr, SDHCI_POWER_CONTROL);

	if (host->vmmc)

		regulator_enable(host->vmmc);



	pr_warning("%s: Switching to 1.8V signalling voltage failed, "

		   "retrying with S18R set to 0\n", mmc_hostname(host->mmc));

		pr_warning("%s: 1.8V regulator output did not became stable\n",

				mmc_hostname(host->mmc));



		return -EAGAIN;

	case MMC_SIGNAL_VOLTAGE_120:

		if (host->vqmmc) {

			ret = regulator_set_voltage(host->vqmmc, 1100000, 1300000);

			if (ret) {

				pr_warning("%s: Switching to 1.2V signalling voltage "

						" failed\n", mmc_hostname(host->mmc));

				return -EIO;

			}

		}



static int sdhci_do_start_signal_voltage_switch(struct sdhci_host *host,

						struct mmc_ios *ios)

{

	u16 ctrl;



	/*

	 * Signal Voltage Switching is only applicable for Host Controllers

	 * v3.00 and above.

	 */

	if (host->version < SDHCI_SPEC_300)

		return 0;



	/*

	 * We first check whether the request is to set signalling voltage

	 * to 3.3V. If so, we change the voltage to 3.3V and return quickly.

	 */

	ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);

	if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_330)

		return sdhci_do_3_3v_signal_voltage_switch(host, ctrl);

	else if (!(ctrl & SDHCI_CTRL_VDD_180) &&

			(ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180))

		return sdhci_do_1_8v_signal_voltage_switch(host, ctrl);

	else

	default:

		/* No signal voltage switch required */

		return 0;

	}

}



static int sdhci_start_signal_voltage_switch(struct mmc_host *mmc,

	struct mmc_ios *ios)

	int signal_voltage)

{

	struct sdhci_host *host = mmc_priv(mmc);

	int err;
@@ -1761,11 +1711,24 @@ static int sdhci_start_signal_voltage_switch(struct mmc_host *mmc, 
	if (host->version < SDHCI_SPEC_300)

		return 0;

	sdhci_runtime_pm_get(host);

	err = sdhci_do_start_signal_voltage_switch(host, ios);

	err = sdhci_do_start_signal_voltage_switch(host, signal_voltage);

	sdhci_runtime_pm_put(host);

	return err;

}



static int sdhci_card_busy(struct mmc_host *mmc)

{

	struct sdhci_host *host = mmc_priv(mmc);

	u32 present_state;



	sdhci_runtime_pm_get(host);

	/* Check whether DAT[3:0] is 0000 */

	present_state = sdhci_readl(host, SDHCI_PRESENT_STATE);

	sdhci_runtime_pm_put(host);



	return !(present_state & SDHCI_DATA_LVL_MASK);

}



static int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode)

{

	struct sdhci_host *host;
@@ -2036,6 +1999,7 @@ static const struct mmc_host_ops sdhci_ops = { 
	.execute_tuning			= sdhci_execute_tuning,

	.enable_preset_value		= sdhci_enable_preset_value,

	.card_event			= sdhci_card_event,

	.card_busy	= sdhci_card_busy,

};



/*****************************************************************************\