Merge tty-next into 3.6-rc1

This handles the merge issue in:
	arch/um/drivers/line.c
	arch/um/drivers/line.h
And resolves the duplicate patches that were in both trees do to the
tty-next branch not getting merged into 3.6-rc1.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

10 files changed, 337 insertions, 216 deletions

diff --git a/drivers/mmc/core/Makefile b/drivers/mmc/core/Makefile
index dca4428380f1..38ed210ce2f3 100644
--- a/drivers/mmc/core/Makefile
+++ b/drivers/mmc/core/Makefile
@@ -7,6 +7,6 @@ mmc_core-y			:= core.o bus.o host.o \
 				   mmc.o mmc_ops.o sd.o sd_ops.o \
 				   sdio.o sdio_ops.o sdio_bus.o \
 				   sdio_cis.o sdio_io.o sdio_irq.o \
-				   quirks.o cd-gpio.o
+				   quirks.o slot-gpio.o
 
 mmc_core-$(CONFIG_DEBUG_FS)	+= debugfs.o
diff --git a/drivers/mmc/core/cd-gpio.c b/drivers/mmc/core/cd-gpio.c
deleted file mode 100644
index 8f5dc08d6598..000000000000
--- a/drivers/mmc/core/cd-gpio.c
+++ /dev/null
@@ -1,83 +0,0 @@
-/*
- * Generic GPIO card-detect helper
- *
- * Copyright (C) 2011, Guennadi Liakhovetski <g.liakhovetski@gmx.de>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-
-#include <linux/err.h>
-#include <linux/gpio.h>
-#include <linux/interrupt.h>
-#include <linux/jiffies.h>
-#include <linux/mmc/cd-gpio.h>
-#include <linux/mmc/host.h>
-#include <linux/module.h>
-#include <linux/slab.h>
-
-struct mmc_cd_gpio {
-	unsigned int gpio;
-	char label[0];
-};
-
-static irqreturn_t mmc_cd_gpio_irqt(int irq, void *dev_id)
-{
-	/* Schedule a card detection after a debounce timeout */
-	mmc_detect_change(dev_id, msecs_to_jiffies(100));
-	return IRQ_HANDLED;
-}
-
-int mmc_cd_gpio_request(struct mmc_host *host, unsigned int gpio)
-{
-	size_t len = strlen(dev_name(host->parent)) + 4;
-	struct mmc_cd_gpio *cd;
-	int irq = gpio_to_irq(gpio);
-	int ret;
-
-	if (irq < 0)
-		return irq;
-
-	cd = kmalloc(sizeof(*cd) + len, GFP_KERNEL);
-	if (!cd)
-		return -ENOMEM;
-
-	snprintf(cd->label, len, "%s cd", dev_name(host->parent));
-
-	ret = gpio_request_one(gpio, GPIOF_DIR_IN, cd->label);
-	if (ret < 0)
-		goto egpioreq;
-
-	ret = request_threaded_irq(irq, NULL, mmc_cd_gpio_irqt,
-				   IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING |
-				   IRQF_ONESHOT, cd->label, host);
-	if (ret < 0)
-		goto eirqreq;
-
-	cd->gpio = gpio;
-	host->hotplug.irq = irq;
-	host->hotplug.handler_priv = cd;
-
-	return 0;
-
-eirqreq:
-	gpio_free(gpio);
-egpioreq:
-	kfree(cd);
-	return ret;
-}
-EXPORT_SYMBOL(mmc_cd_gpio_request);
-
-void mmc_cd_gpio_free(struct mmc_host *host)
-{
-	struct mmc_cd_gpio *cd = host->hotplug.handler_priv;
-
-	if (!cd)
-		return;
-
-	free_irq(host->hotplug.irq, host);
-	gpio_free(cd->gpio);
-	kfree(cd);
-}
-EXPORT_SYMBOL(mmc_cd_gpio_free);
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 0b6141d29dbd..8ac5246e2ab2 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -404,6 +404,7 @@ int mmc_interrupt_hpi(struct mmc_card *card)
 {
 	int err;
 	u32 status;
+	unsigned long prg_wait;
 
 	BUG_ON(!card);
 
@@ -419,30 +420,38 @@ int mmc_interrupt_hpi(struct mmc_card *card)
 		goto out;
 	}
 
-	/*
-	 * If the card status is in PRG-state, we can send the HPI command.
-	 */
-	if (R1_CURRENT_STATE(status) == R1_STATE_PRG) {
-		do {
-			/*
-			 * We don't know when the HPI command will finish
-			 * processing, so we need to resend HPI until out
-			 * of prg-state, and keep checking the card status
-			 * with SEND_STATUS.  If a timeout error occurs when
-			 * sending the HPI command, we are already out of
-			 * prg-state.
-			 */
-			err = mmc_send_hpi_cmd(card, &status);
-			if (err)
-				pr_debug("%s: abort HPI (%d error)\n",
-					 mmc_hostname(card->host), err);
+	switch (R1_CURRENT_STATE(status)) {
+	case R1_STATE_IDLE:
+	case R1_STATE_READY:
+	case R1_STATE_STBY:
+		/*
+		 * In idle states, HPI is not needed and the caller
+		 * can issue the next intended command immediately
+		 */
+		goto out;
+	case R1_STATE_PRG:
+		break;
+	default:
+		/* In all other states, it's illegal to issue HPI */
+		pr_debug("%s: HPI cannot be sent. Card state=%d\n",
+			mmc_hostname(card->host), R1_CURRENT_STATE(status));
+		err = -EINVAL;
+		goto out;
+	}
 
-			err = mmc_send_status(card, &status);
-			if (err)
-				break;
-		} while (R1_CURRENT_STATE(status) == R1_STATE_PRG);
-	} else
-		pr_debug("%s: Left prg-state\n", mmc_hostname(card->host));
+	err = mmc_send_hpi_cmd(card, &status);
+	if (err)
+		goto out;
+
+	prg_wait = jiffies + msecs_to_jiffies(card->ext_csd.out_of_int_time);
+	do {
+		err = mmc_send_status(card, &status);
+
+		if (!err && R1_CURRENT_STATE(status) == R1_STATE_TRAN)
+			break;
+		if (time_after(jiffies, prg_wait))
+			err = -ETIMEDOUT;
+	} while (!err);
 
 out:
 	mmc_release_host(card->host);
@@ -941,7 +950,7 @@ int mmc_regulator_get_ocrmask(struct regulator *supply)
 
 	return result;
 }
-EXPORT_SYMBOL(mmc_regulator_get_ocrmask);
+EXPORT_SYMBOL_GPL(mmc_regulator_get_ocrmask);
 
 /**
  * mmc_regulator_set_ocr - set regulator to match host->ios voltage
@@ -1011,7 +1020,30 @@ int mmc_regulator_set_ocr(struct mmc_host *mmc,
 			"could not set regulator OCR (%d)\n", result);
 	return result;
 }
-EXPORT_SYMBOL(mmc_regulator_set_ocr);
+EXPORT_SYMBOL_GPL(mmc_regulator_set_ocr);
+
+int mmc_regulator_get_supply(struct mmc_host *mmc)
+{
+	struct device *dev = mmc_dev(mmc);
+	struct regulator *supply;
+	int ret;
+
+	supply = devm_regulator_get(dev, "vmmc");
+	mmc->supply.vmmc = supply;
+	mmc->supply.vqmmc = devm_regulator_get(dev, "vqmmc");
+
+	if (IS_ERR(supply))
+		return PTR_ERR(supply);
+
+	ret = mmc_regulator_get_ocrmask(supply);
+	if (ret > 0)
+		mmc->ocr_avail = ret;
+	else
+		dev_warn(mmc_dev(mmc), "Failed getting OCR mask: %d\n", ret);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(mmc_regulator_get_supply);
 
 #endif /* CONFIG_REGULATOR */
 
@@ -1180,6 +1212,9 @@ static void mmc_power_up(struct mmc_host *host)
 	host->ios.timing = MMC_TIMING_LEGACY;
 	mmc_set_ios(host);
 
+	/* Set signal voltage to 3.3V */
+	mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330, false);
+
 	/*
 	 * This delay should be sufficient to allow the power supply
 	 * to reach the minimum voltage.
@@ -1931,9 +1966,6 @@ static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
 	 */
 	mmc_hw_reset_for_init(host);
 
-	/* Initialization should be done at 3.3 V I/O voltage. */
-	mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330, 0);
-
 	/*
 	 * sdio_reset sends CMD52 to reset card.  Since we do not know
 	 * if the card is being re-initialized, just send it.  CMD52
@@ -2075,6 +2107,7 @@ void mmc_rescan(struct work_struct *work)
 void mmc_start_host(struct mmc_host *host)
 {
 	host->f_init = max(freqs[0], host->f_min);
+	host->rescan_disable = 0;
 	mmc_power_up(host);
 	mmc_detect_change(host, 0);
 }
@@ -2088,6 +2121,7 @@ void mmc_stop_host(struct mmc_host *host)
 	spin_unlock_irqrestore(&host->lock, flags);
 #endif
 
+	host->rescan_disable = 1;
 	cancel_delayed_work_sync(&host->detect);
 	mmc_flush_scheduled_work();
 
diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c
index 91c84c7a1829..597f189b4427 100644
--- a/drivers/mmc/core/host.c
+++ b/drivers/mmc/core/host.c
@@ -32,6 +32,7 @@
 static void mmc_host_classdev_release(struct device *dev)
 {
 	struct mmc_host *host = cls_dev_to_mmc_host(dev);
+	mutex_destroy(&host->slot.lock);
 	kfree(host);
 }
 
@@ -312,6 +313,8 @@ struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
 	if (!host)
 		return NULL;
 
+	/* scanning will be enabled when we're ready */
+	host->rescan_disable = 1;
 	spin_lock(&mmc_host_lock);
 	err = idr_get_new(&mmc_host_idr, host, &host->index);
 	spin_unlock(&mmc_host_lock);
@@ -327,6 +330,9 @@ struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
 
 	mmc_host_clk_init(host);
 
+	mutex_init(&host->slot.lock);
+	host->slot.cd_irq = -EINVAL;
+
 	spin_lock_init(&host->lock);
 	init_waitqueue_head(&host->wq);
 	INIT_DELAYED_WORK(&host->detect, mmc_rescan);
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 4f4489aa6bae..396b25891bb9 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -818,9 +818,6 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
 	if (!mmc_host_is_spi(host))
 		mmc_set_bus_mode(host, MMC_BUSMODE_OPENDRAIN);
 
-	/* Initialization should be done at 3.3 V I/O voltage. */
-	mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330, 0);
-
 	/*
 	 * Since we're changing the OCR value, we seem to
 	 * need to tell some cards to go back to the idle
diff --git a/drivers/mmc/core/mmc_ops.c b/drivers/mmc/core/mmc_ops.c
index 69370f494e05..0ed2cc5f35b6 100644
--- a/drivers/mmc/core/mmc_ops.c
+++ b/drivers/mmc/core/mmc_ops.c
@@ -569,7 +569,6 @@ int mmc_send_hpi_cmd(struct mmc_card *card, u32 *status)
 
 	cmd.opcode = opcode;
 	cmd.arg = card->rca << 16 | 1;
-	cmd.cmd_timeout_ms = card->ext_csd.out_of_int_time;
 
 	err = mmc_wait_for_cmd(card->host, &cmd, 0);
 	if (err) {
diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
index b2b43f624b9e..74972c241dff 100644
--- a/drivers/mmc/core/sd.c
+++ b/drivers/mmc/core/sd.c
@@ -244,7 +244,7 @@ static int mmc_read_ssr(struct mmc_card *card)
 	 * bitfield positions accordingly.
 	 */
 	au = UNSTUFF_BITS(ssr, 428 - 384, 4);
-	if (au > 0 || au <= 9) {
+	if (au > 0 && au <= 9) {
 		card->ssr.au = 1 << (au + 4);
 		es = UNSTUFF_BITS(ssr, 408 - 384, 16);
 		et = UNSTUFF_BITS(ssr, 402 - 384, 6);
@@ -290,8 +290,12 @@ static int mmc_read_switch(struct mmc_card *card)
 		return -ENOMEM;
 	}
 
-	/* Find out the supported Bus Speed Modes. */
-	err = mmc_sd_switch(card, 0, 0, 1, status);
+	/*
+	 * Find out the card's support bits with a mode 0 operation.
+	 * The argument does not matter, as the support bits do not
+	 * change with the arguments.
+	 */
+	err = mmc_sd_switch(card, 0, 0, 0, status);
 	if (err) {
 		/*
 		 * If the host or the card can't do the switch,
@@ -312,46 +316,8 @@ static int mmc_read_switch(struct mmc_card *card)
 
 	if (card->scr.sda_spec3) {
 		card->sw_caps.sd3_bus_mode = status[13];
-
-		/* Find out Driver Strengths supported by the card */
-		err = mmc_sd_switch(card, 0, 2, 1, status);
-		if (err) {
-			/*
-			 * If the host or the card can't do the switch,
-			 * fail more gracefully.
-			 */
-			if (err != -EINVAL && err != -ENOSYS && err != -EFAULT)
-				goto out;
-
-			pr_warning("%s: problem reading "
-				"Driver Strength.\n",
-				mmc_hostname(card->host));
-			err = 0;
-
-			goto out;
-		}
-
+		/* Driver Strengths supported by the card */
 		card->sw_caps.sd3_drv_type = status[9];
-
-		/* Find out Current Limits supported by the card */
-		err = mmc_sd_switch(card, 0, 3, 1, status);
-		if (err) {
-			/*
-			 * If the host or the card can't do the switch,
-			 * fail more gracefully.
-			 */
-			if (err != -EINVAL && err != -ENOSYS && err != -EFAULT)
-				goto out;
-
-			pr_warning("%s: problem reading "
-				"Current Limit.\n",
-				mmc_hostname(card->host));
-			err = 0;
-
-			goto out;
-		}
-
-		card->sw_caps.sd3_curr_limit = status[7];
 	}
 
 out:
@@ -551,60 +517,80 @@ static int sd_set_bus_speed_mode(struct mmc_card *card, u8 *status)
 	return 0;
 }
 
+/* Get host's max current setting at its current voltage */
+static u32 sd_get_host_max_current(struct mmc_host *host)
+{
+	u32 voltage, max_current;
+
+	voltage = 1 << host->ios.vdd;
+	switch (voltage) {
+	case MMC_VDD_165_195:
+		max_current = host->max_current_180;
+		break;
+	case MMC_VDD_29_30:
+	case MMC_VDD_30_31:
+		max_current = host->max_current_300;
+		break;
+	case MMC_VDD_32_33:
+	case MMC_VDD_33_34:
+		max_current = host->max_current_330;
+		break;
+	default:
+		max_current = 0;
+	}
+
+	return max_current;
+}
+
 static int sd_set_current_limit(struct mmc_card *card, u8 *status)
 {
-	int current_limit = 0;
+	int current_limit = SD_SET_CURRENT_NO_CHANGE;
 	int err;
+	u32 max_current;
 
 	/*
 	 * Current limit switch is only defined for SDR50, SDR104, and DDR50
-	 * bus speed modes. For other bus speed modes, we set the default
-	 * current limit of 200mA.
+	 * bus speed modes. For other bus speed modes, we do not change the
+	 * current limit.
 	 */
-	if ((card->sd_bus_speed == UHS_SDR50_BUS_SPEED) ||
-	    (card->sd_bus_speed == UHS_SDR104_BUS_SPEED) ||
-	    (card->sd_bus_speed == UHS_DDR50_BUS_SPEED)) {
-		if (card->host->caps & MMC_CAP_MAX_CURRENT_800) {
-			if (card->sw_caps.sd3_curr_limit & SD_MAX_CURRENT_800)
-				current_limit = SD_SET_CURRENT_LIMIT_800;
-			else if (card->sw_caps.sd3_curr_limit &
-					SD_MAX_CURRENT_600)
-				current_limit = SD_SET_CURRENT_LIMIT_600;
-			else if (card->sw_caps.sd3_curr_limit &
-					SD_MAX_CURRENT_400)
-				current_limit = SD_SET_CURRENT_LIMIT_400;
-			else if (card->sw_caps.sd3_curr_limit &
-					SD_MAX_CURRENT_200)
-				current_limit = SD_SET_CURRENT_LIMIT_200;
-		} else if (card->host->caps & MMC_CAP_MAX_CURRENT_600) {
-			if (card->sw_caps.sd3_curr_limit & SD_MAX_CURRENT_600)
-				current_limit = SD_SET_CURRENT_LIMIT_600;
-			else if (card->sw_caps.sd3_curr_limit &
-					SD_MAX_CURRENT_400)
-				current_limit = SD_SET_CURRENT_LIMIT_400;
-			else if (card->sw_caps.sd3_curr_limit &
-					SD_MAX_CURRENT_200)
-				current_limit = SD_SET_CURRENT_LIMIT_200;
-		} else if (card->host->caps & MMC_CAP_MAX_CURRENT_400) {
-			if (card->sw_caps.sd3_curr_limit & SD_MAX_CURRENT_400)
-				current_limit = SD_SET_CURRENT_LIMIT_400;
-			else if (card->sw_caps.sd3_curr_limit &
-					SD_MAX_CURRENT_200)
-				current_limit = SD_SET_CURRENT_LIMIT_200;
-		} else if (card->host->caps & MMC_CAP_MAX_CURRENT_200) {
-			if (card->sw_caps.sd3_curr_limit & SD_MAX_CURRENT_200)
-				current_limit = SD_SET_CURRENT_LIMIT_200;
-		}
-	} else
+	if ((card->sd_bus_speed != UHS_SDR50_BUS_SPEED) &&
+	    (card->sd_bus_speed != UHS_SDR104_BUS_SPEED) &&
+	    (card->sd_bus_speed != UHS_DDR50_BUS_SPEED))
+		return 0;
+
+	/*
+	 * Host has different current capabilities when operating at
+	 * different voltages, so find out its max current first.
+	 */
+	max_current = sd_get_host_max_current(card->host);
+
+	/*
+	 * We only check host's capability here, if we set a limit that is
+	 * higher than the card's maximum current, the card will be using its
+	 * maximum current, e.g. if the card's maximum current is 300ma, and
+	 * when we set current limit to 200ma, the card will draw 200ma, and
+	 * when we set current limit to 400/600/800ma, the card will draw its
+	 * maximum 300ma from the host.
+	 */
+	if (max_current >= 800)
+		current_limit = SD_SET_CURRENT_LIMIT_800;
+	else if (max_current >= 600)
+		current_limit = SD_SET_CURRENT_LIMIT_600;
+	else if (max_current >= 400)
+		current_limit = SD_SET_CURRENT_LIMIT_400;
+	else if (max_current >= 200)
 		current_limit = SD_SET_CURRENT_LIMIT_200;
 
-	err = mmc_sd_switch(card, 1, 3, current_limit, status);
-	if (err)
-		return err;
+	if (current_limit != SD_SET_CURRENT_NO_CHANGE) {
+		err = mmc_sd_switch(card, 1, 3, current_limit, status);
+		if (err)
+			return err;
 
-	if (((status[15] >> 4) & 0x0F) != current_limit)
-		pr_warning("%s: Problem setting current limit!\n",
-			mmc_hostname(card->host));
+		if (((status[15] >> 4) & 0x0F) != current_limit)
+			pr_warning("%s: Problem setting current limit!\n",
+				mmc_hostname(card->host));
+
+	}
 
 	return 0;
 }
@@ -726,6 +712,7 @@ struct device_type sd_type = {
 int mmc_sd_get_cid(struct mmc_host *host, u32 ocr, u32 *cid, u32 *rocr)
 {
 	int err;
+	u32 max_current;
 
 	/*
 	 * Since we're changing the OCR value, we seem to
@@ -753,9 +740,12 @@ int mmc_sd_get_cid(struct mmc_host *host, u32 ocr, u32 *cid, u32 *rocr)
 	    MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR104 | MMC_CAP_UHS_DDR50))
 		ocr |= SD_OCR_S18R;
 
-	/* If the host can supply more than 150mA, XPC should be set to 1. */
-	if (host->caps & (MMC_CAP_SET_XPC_330 | MMC_CAP_SET_XPC_300 |
-	    MMC_CAP_SET_XPC_180))
+	/*
+	 * If the host can supply more than 150mA at current voltage,
+	 * XPC should be set to 1.
+	 */
+	max_current = sd_get_host_max_current(host);
+	if (max_current > 150)
 		ocr |= SD_OCR_XPC;
 
 try_again:
@@ -911,9 +901,6 @@ static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
 	BUG_ON(!host);
 	WARN_ON(!host->claimed);
 
-	/* The initialization should be done at 3.3 V I/O voltage. */
-	mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330, 0);
-
 	err = mmc_sd_get_cid(host, ocr, cid, &rocr);
 	if (err)
 		return err;
diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
index 41c5fd8848f4..d4619e2ec030 100644
--- a/drivers/mmc/core/sdio.c
+++ b/drivers/mmc/core/sdio.c
@@ -591,9 +591,6 @@ static int mmc_sdio_init_card(struct mmc_host *host, u32 ocr,
 	 * Inform the card of the voltage
 	 */
 	if (!powered_resume) {
-		/* The initialization should be done at 3.3 V I/O voltage. */
-		mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330, 0);
-
 		err = mmc_send_io_op_cond(host, host->ocr, &ocr);
 		if (err)
 			goto err;
@@ -1006,10 +1003,6 @@ static int mmc_sdio_power_restore(struct mmc_host *host)
 	 * restore the correct voltage setting of the card.
 	 */
 
-	/* The initialization should be done at 3.3 V I/O voltage. */
-	if (!mmc_card_keep_power(host))
-		mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330, 0);
-
 	sdio_reset(host);
 	mmc_go_idle(host);
 	mmc_send_if_cond(host, host->ocr_avail);
diff --git a/drivers/mmc/core/sdio_cis.c b/drivers/mmc/core/sdio_cis.c
index f1c7ed8f4d85..8e94e555b788 100644
--- a/drivers/mmc/core/sdio_cis.c
+++ b/drivers/mmc/core/sdio_cis.c
@@ -313,7 +313,7 @@ static int sdio_read_cis(struct mmc_card *card, struct sdio_func *func)
 
 			if (ret == -ENOENT) {
 				/* warn about unknown tuples */
-				pr_warning("%s: queuing unknown"
+				pr_warn_ratelimited("%s: queuing unknown"
 				       " CIS tuple 0x%02x (%u bytes)\n",
 				       mmc_hostname(card->host),
 				       tpl_code, tpl_link);
diff --git a/drivers/mmc/core/slot-gpio.c b/drivers/mmc/core/slot-gpio.c
new file mode 100644
index 000000000000..058242916cef
--- /dev/null
+++ b/drivers/mmc/core/slot-gpio.c
@@ -0,0 +1,188 @@
+/*
+ * Generic GPIO card-detect helper
+ *
+ * Copyright (C) 2011, Guennadi Liakhovetski <g.liakhovetski@gmx.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/jiffies.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/slot-gpio.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+struct mmc_gpio {
+	int ro_gpio;
+	int cd_gpio;
+	char *ro_label;
+	char cd_label[0];
+};
+
+static irqreturn_t mmc_gpio_cd_irqt(int irq, void *dev_id)
+{
+	/* Schedule a card detection after a debounce timeout */
+	mmc_detect_change(dev_id, msecs_to_jiffies(100));
+	return IRQ_HANDLED;
+}
+
+static int mmc_gpio_alloc(struct mmc_host *host)
+{
+	size_t len = strlen(dev_name(host->parent)) + 4;
+	struct mmc_gpio *ctx;
+
+	mutex_lock(&host->slot.lock);
+
+	ctx = host->slot.handler_priv;
+	if (!ctx) {
+		/*
+		 * devm_kzalloc() can be called after device_initialize(), even
+		 * before device_add(), i.e., between mmc_alloc_host() and
+		 * mmc_add_host()
+		 */
+		ctx = devm_kzalloc(&host->class_dev, sizeof(*ctx) + 2 * len,
+				   GFP_KERNEL);
+		if (ctx) {
+			ctx->ro_label = ctx->cd_label + len;
+			snprintf(ctx->cd_label, len, "%s cd", dev_name(host->parent));
+			snprintf(ctx->ro_label, len, "%s ro", dev_name(host->parent));
+			ctx->cd_gpio = -EINVAL;
+			ctx->ro_gpio = -EINVAL;
+			host->slot.handler_priv = ctx;
+		}
+	}
+
+	mutex_unlock(&host->slot.lock);
+
+	return ctx ? 0 : -ENOMEM;
+}
+
+int mmc_gpio_get_ro(struct mmc_host *host)
+{
+	struct mmc_gpio *ctx = host->slot.handler_priv;
+
+	if (!ctx || !gpio_is_valid(ctx->ro_gpio))
+		return -ENOSYS;
+
+	return !gpio_get_value_cansleep(ctx->ro_gpio) ^
+		!!(host->caps2 & MMC_CAP2_RO_ACTIVE_HIGH);
+}
+EXPORT_SYMBOL(mmc_gpio_get_ro);
+
+int mmc_gpio_get_cd(struct mmc_host *host)
+{
+	struct mmc_gpio *ctx = host->slot.handler_priv;
+
+	if (!ctx || !gpio_is_valid(ctx->cd_gpio))
+		return -ENOSYS;
+
+	return !gpio_get_value_cansleep(ctx->cd_gpio) ^
+		!!(host->caps2 & MMC_CAP2_CD_ACTIVE_HIGH);
+}
+EXPORT_SYMBOL(mmc_gpio_get_cd);
+
+int mmc_gpio_request_ro(struct mmc_host *host, unsigned int gpio)
+{
+	struct mmc_gpio *ctx;
+	int ret;
+
+	if (!gpio_is_valid(gpio))
+		return -EINVAL;
+
+	ret = mmc_gpio_alloc(host);
+	if (ret < 0)
+		return ret;
+
+	ctx = host->slot.handler_priv;
+
+	return gpio_request_one(gpio, GPIOF_DIR_IN, ctx->ro_label);
+}
+EXPORT_SYMBOL(mmc_gpio_request_ro);
+
+int mmc_gpio_request_cd(struct mmc_host *host, unsigned int gpio)
+{
+	struct mmc_gpio *ctx;
+	int irq = gpio_to_irq(gpio);
+	int ret;
+
+	ret = mmc_gpio_alloc(host);
+	if (ret < 0)
+		return ret;
+
+	ctx = host->slot.handler_priv;
+
+	ret = gpio_request_one(gpio, GPIOF_DIR_IN, ctx->cd_label);
+	if (ret < 0)
+		/*
+		 * don't bother freeing memory. It might still get used by other
+		 * slot functions, in any case it will be freed, when the device
+		 * is destroyed.
+		 */
+		return ret;
+
+	/*
+	 * Even if gpio_to_irq() returns a valid IRQ number, the platform might
+	 * still prefer to poll, e.g., because that IRQ number is already used
+	 * by another unit and cannot be shared.
+	 */
+	if (irq >= 0 && host->caps & MMC_CAP_NEEDS_POLL)
+		irq = -EINVAL;
+
+	if (irq >= 0) {
+		ret = request_threaded_irq(irq, NULL, mmc_gpio_cd_irqt,
+			IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+			ctx->cd_label, host);
+		if (ret < 0)
+			irq = ret;
+	}
+
+	host->slot.cd_irq = irq;
+
+	if (irq < 0)
+		host->caps |= MMC_CAP_NEEDS_POLL;
+
+	ctx->cd_gpio = gpio;
+
+	return 0;
+}
+EXPORT_SYMBOL(mmc_gpio_request_cd);
+
+void mmc_gpio_free_ro(struct mmc_host *host)
+{
+	struct mmc_gpio *ctx = host->slot.handler_priv;
+	int gpio;
+
+	if (!ctx || !gpio_is_valid(ctx->ro_gpio))
+		return;
+
+	gpio = ctx->ro_gpio;
+	ctx->ro_gpio = -EINVAL;
+
+	gpio_free(gpio);
+}
+EXPORT_SYMBOL(mmc_gpio_free_ro);
+
+void mmc_gpio_free_cd(struct mmc_host *host)
+{
+	struct mmc_gpio *ctx = host->slot.handler_priv;
+	int gpio;
+
+	if (!ctx || !gpio_is_valid(ctx->cd_gpio))
+		return;
+
+	if (host->slot.cd_irq >= 0) {
+		free_irq(host->slot.cd_irq, host);
+		host->slot.cd_irq = -EINVAL;
+	}
+
+	gpio = ctx->cd_gpio;
+	ctx->cd_gpio = -EINVAL;
+
+	gpio_free(gpio);
+}
+EXPORT_SYMBOL(mmc_gpio_free_cd);