Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Victor Shih <victorshihgli@gmail.com>
To:     ulf.hansson@linaro.org, adrian.hunter@intel.com
Cc:     linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org,
        benchuanggli@gmail.com, HL.Liu@genesyslogic.com.tw,
        Greg.tu@genesyslogic.com.tw, takahiro.akashi@linaro.org,
        dlunev@chromium.org, Victor Shih <victor.shih@genesyslogic.com.tw>,
        Ben Chuang <ben.chuang@genesyslogic.com.tw>
Subject: [PATCH V6 18/24] mmc: sdhci-uhs2: add request() and others
Date:   Tue, 13 Dec 2022 17:00:41 +0800
Message-Id: <20221213090047.3805-19-victor.shih@genesyslogic.com.tw>
In-Reply-To: <20221213090047.3805-1-victor.shih@genesyslogic.com.tw>
References: <20221213090047.3805-1-victor.shih@genesyslogic.com.tw>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

This is a sdhci version of mmc's request operation.
It covers both UHS-I and UHS-II.

Signed-off-by: Ben Chuang <ben.chuang@genesyslogic.com.tw>
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Victor Shih <victor.shih@genesyslogic.com.tw>
---
 drivers/mmc/host/sdhci-uhs2.c | 418 ++++++++++++++++++++++++++++++++++
 drivers/mmc/host/sdhci.c      |  78 ++++---
 drivers/mmc/host/sdhci.h      |  14 ++
 3 files changed, 481 insertions(+), 29 deletions(-)

diff --git a/drivers/mmc/host/sdhci-uhs2.c b/drivers/mmc/host/sdhci-uhs2.c
index de15a6559702..7a34f66c4215 100644
--- a/drivers/mmc/host/sdhci-uhs2.c
+++ b/drivers/mmc/host/sdhci-uhs2.c
@@ -15,6 +15,7 @@
 #include <linux/iopoll.h>
 #include <linux/bitfield.h>
 #include <linux/ktime.h>
+#include <linux/mmc/mmc.h>
 
 #include "sdhci.h"
 #include "sdhci-uhs2.h"
@@ -25,6 +26,8 @@
 #define SDHCI_UHS2_DUMP(f, x...) \
 	pr_err("%s: " DRIVER_NAME ": " f, mmc_hostname(host->mmc), ## x)
 
+#define UHS2_ARG_IOADR_MASK 0xfff
+
 void sdhci_uhs2_dump_regs(struct sdhci_host *host)
 {
 	if (!(host->mmc->flags & MMC_UHS2_SUPPORT))
@@ -59,6 +62,11 @@ EXPORT_SYMBOL_GPL(sdhci_uhs2_dump_regs);
  *                                                                           *
 \*****************************************************************************/
 
+static inline u16 uhs2_dev_cmd(struct mmc_command *cmd)
+{
+	return be16_to_cpu((__be16)cmd->uhs2_cmd->arg) & UHS2_ARG_IOADR_MASK;
+}
+
 static inline int mmc_opt_regulator_set_ocr(struct mmc_host *mmc,
 					    struct regulator *supply,
 					    unsigned short vdd_bit)
@@ -452,6 +460,415 @@ static int sdhci_uhs2_control(struct mmc_host *mmc, enum sd_uhs2_operation op)
 	return err;
 }
 
+/*****************************************************************************\
+ *                                                                           *
+ * Core functions                                                            *
+ *                                                                           *
+\*****************************************************************************/
+
+static void sdhci_uhs2_prepare_data(struct sdhci_host *host,
+				    struct mmc_command *cmd)
+{
+	struct mmc_data *data = cmd->data;
+
+	sdhci_initialize_data(host, data);
+
+	sdhci_prepare_dma(host, data);
+
+	sdhci_writew(host, data->blksz, SDHCI_UHS2_BLOCK_SIZE);
+	sdhci_writew(host, data->blocks, SDHCI_UHS2_BLOCK_COUNT);
+}
+
+static void sdhci_uhs2_finish_data(struct sdhci_host *host)
+{
+	struct mmc_data *data = host->data;
+
+	__sdhci_finish_data_common(host);
+
+	__sdhci_finish_mrq(host, data->mrq);
+}
+
+static void sdhci_uhs2_set_transfer_mode(struct sdhci_host *host,
+					 struct mmc_command *cmd)
+{
+	u16 mode;
+	struct mmc_data *data = cmd->data;
+
+	if (!data) {
+		/* clear Auto CMD settings for no data CMDs */
+		if (uhs2_dev_cmd(cmd) == UHS2_DEV_CMD_TRANS_ABORT) {
+			mode =  0;
+		} else {
+			mode = sdhci_readw(host, SDHCI_UHS2_TRANS_MODE);
+			if (cmd->opcode == MMC_STOP_TRANSMISSION || cmd->opcode == MMC_ERASE)
+				mode |= SDHCI_UHS2_TRNS_WAIT_EBSY;
+			else
+				/* send status mode */
+				if (cmd->opcode == MMC_SEND_STATUS)
+					mode = 0;
+		}
+
+		DBG("UHS2 no data trans mode is 0x%x.\n", mode);
+
+		sdhci_writew(host, mode, SDHCI_UHS2_TRANS_MODE);
+		return;
+	}
+
+	WARN_ON(!host->data);
+
+	mode = SDHCI_UHS2_TRNS_BLK_CNT_EN | SDHCI_UHS2_TRNS_WAIT_EBSY;
+	if (data->flags & MMC_DATA_WRITE)
+		mode |= SDHCI_UHS2_TRNS_DATA_TRNS_WRT;
+
+	if (data->blocks == 1 &&
+	    data->blksz != 512 &&
+	    cmd->opcode != MMC_READ_SINGLE_BLOCK &&
+	    cmd->opcode != MMC_WRITE_BLOCK) {
+		mode &= ~SDHCI_UHS2_TRNS_BLK_CNT_EN;
+		mode |= SDHCI_UHS2_TRNS_BLK_BYTE_MODE;
+	}
+
+	if (host->flags & SDHCI_REQ_USE_DMA)
+		mode |= SDHCI_UHS2_TRNS_DMA;
+
+	if ((host->mmc->uhs2_ios.is_2L_HD_mode) && !cmd->uhs2_tmode0_flag)
+		mode |= SDHCI_UHS2_TRNS_2L_HD;
+
+	sdhci_writew(host, mode, SDHCI_UHS2_TRANS_MODE);
+
+	DBG("UHS2 trans mode is 0x%x.\n", mode);
+}
+
+static void __sdhci_uhs2_send_command(struct sdhci_host *host,
+				      struct mmc_command *cmd)
+{
+	int i, j;
+	int cmd_reg;
+
+	i = 0;
+	sdhci_writel(host,
+		     ((u32)cmd->uhs2_cmd->arg << 16) |
+				(u32)cmd->uhs2_cmd->header,
+		     SDHCI_UHS2_CMD_PACKET + i);
+	i += 4;
+
+	/*
+	 * Per spec, playload (config) should be MSB before sending out.
+	 * But we don't need convert here because had set payload as
+	 * MSB when preparing config read/write commands.
+	 */
+	for (j = 0; j < cmd->uhs2_cmd->payload_len / sizeof(u32); j++) {
+		sdhci_writel(host, *(cmd->uhs2_cmd->payload + j), SDHCI_UHS2_CMD_PACKET + i);
+		i += 4;
+	}
+
+	for ( ; i < SDHCI_UHS2_CMD_PACK_MAX_LEN; i += 4)
+		sdhci_writel(host, 0, SDHCI_UHS2_CMD_PACKET + i);
+
+	DBG("UHS2 CMD packet_len = %d.\n", cmd->uhs2_cmd->packet_len);
+	for (i = 0; i < cmd->uhs2_cmd->packet_len; i++)
+		DBG("UHS2 CMD_PACKET[%d] = 0x%x.\n", i,
+		    sdhci_readb(host, SDHCI_UHS2_CMD_PACKET + i));
+
+	cmd_reg = FIELD_PREP(SDHCI_UHS2_CMD_PACK_LEN_MASK, cmd->uhs2_cmd->packet_len);
+	if ((cmd->flags & MMC_CMD_MASK) == MMC_CMD_ADTC)
+		cmd_reg |= SDHCI_UHS2_CMD_DATA;
+	if (cmd->opcode == MMC_STOP_TRANSMISSION)
+		cmd_reg |= SDHCI_UHS2_CMD_CMD12;
+
+	/* UHS2 Native ABORT */
+	if ((cmd->uhs2_cmd->header & UHS2_NATIVE_PACKET) &&
+	    (uhs2_dev_cmd(cmd) == UHS2_DEV_CMD_TRANS_ABORT))
+		cmd_reg |= SDHCI_UHS2_CMD_TRNS_ABORT;
+
+	/* UHS2 Native DORMANT */
+	if ((cmd->uhs2_cmd->header & UHS2_NATIVE_PACKET) &&
+	    (uhs2_dev_cmd(cmd) == UHS2_DEV_CMD_GO_DORMANT_STATE))
+		cmd_reg |= SDHCI_UHS2_CMD_DORMANT;
+
+	DBG("0x%x is set to UHS2 CMD register.\n", cmd_reg);
+
+	sdhci_writew(host, cmd_reg, SDHCI_UHS2_CMD);
+}
+
+static bool sdhci_uhs2_send_command(struct sdhci_host *host,
+				    struct mmc_command *cmd)
+{
+	int flags;
+	u32 mask;
+	unsigned long timeout;
+
+	WARN_ON(host->cmd);
+
+	/* Initially, a command has no error */
+	cmd->error = 0;
+
+	if (cmd->opcode == MMC_STOP_TRANSMISSION)
+		cmd->flags |= MMC_RSP_BUSY;
+
+	mask = SDHCI_CMD_INHIBIT;
+
+	if (sdhci_readl(host, SDHCI_PRESENT_STATE) & mask)
+		return false;
+
+	host->cmd = cmd;
+	host->data_timeout = 0;
+	if (sdhci_data_line_cmd(cmd)) {
+		WARN_ON(host->data_cmd);
+		host->data_cmd = cmd;
+		__sdhci_uhs2_set_timeout(host);
+	}
+
+	if (cmd->data)
+		sdhci_uhs2_prepare_data(host, cmd);
+
+	sdhci_uhs2_set_transfer_mode(host, cmd);
+
+	if ((cmd->flags & MMC_RSP_136) && (cmd->flags & MMC_RSP_BUSY)) {
+		WARN_ONCE(1, "Unsupported response type!\n");
+		/*
+		 * This does not happen in practice because 136-bit response
+		 * commands never have busy waiting, so rather than complicate
+		 * the error path, just remove busy waiting and continue.
+		 */
+		cmd->flags &= ~MMC_RSP_BUSY;
+	}
+
+	if (!(cmd->flags & MMC_RSP_PRESENT))
+		flags = SDHCI_CMD_RESP_NONE;
+	else if (cmd->flags & MMC_RSP_136)
+		flags = SDHCI_CMD_RESP_LONG;
+	else if (cmd->flags & MMC_RSP_BUSY)
+		flags = SDHCI_CMD_RESP_SHORT_BUSY;
+	else
+		flags = SDHCI_CMD_RESP_SHORT;
+
+	if (cmd->flags & MMC_RSP_CRC)
+		flags |= SDHCI_CMD_CRC;
+	if (cmd->flags & MMC_RSP_OPCODE)
+		flags |= SDHCI_CMD_INDEX;
+
+	timeout = jiffies;
+	if (host->data_timeout)
+		timeout += nsecs_to_jiffies(host->data_timeout);
+	else if (!cmd->data && cmd->busy_timeout > 9000)
+		timeout += DIV_ROUND_UP(cmd->busy_timeout, 1000) * HZ + HZ;
+	else
+		timeout += 10 * HZ;
+	sdhci_mod_timer(host, cmd->mrq, timeout);
+
+	__sdhci_uhs2_send_command(host, cmd);
+
+	return true;
+}
+
+static bool sdhci_uhs2_send_command_retry(struct sdhci_host *host,
+				     struct mmc_command *cmd,
+				     unsigned long flags)
+	__releases(host->lock)
+	__acquires(host->lock)
+{
+	struct mmc_command *deferred_cmd = host->deferred_cmd;
+	int timeout = 10; /* Approx. 10 ms */
+	bool present;
+
+	while (!sdhci_uhs2_send_command(host, cmd)) {
+		if (!timeout--) {
+			pr_err("%s: Controller never released inhibit bit(s).\n",
+			       mmc_hostname(host->mmc));
+			sdhci_dumpregs(host);
+			cmd->error = -EIO;
+			return false;
+		}
+
+		spin_unlock_irqrestore(&host->lock, flags);
+
+		usleep_range(1000, 1250);
+
+		present = host->mmc->ops->get_cd(host->mmc);
+
+		spin_lock_irqsave(&host->lock, flags);
+
+		/* A deferred command might disappear, handle that */
+		if (cmd == deferred_cmd && cmd != host->deferred_cmd)
+			return true;
+
+		if (sdhci_present_error(host, cmd, present))
+			return false;
+	}
+
+	if (cmd == host->deferred_cmd)
+		host->deferred_cmd = NULL;
+
+	return true;
+}
+
+static void __sdhci_uhs2_finish_command(struct sdhci_host *host)
+{
+	struct mmc_command *cmd = host->cmd;
+	u8 resp;
+	u8 ecode;
+	bool bReadA0 = 0;
+	int i;
+
+	if (host->mmc->card) {
+		if (host->mmc->card->uhs2_state & MMC_UHS2_INITIALIZED) {
+			resp = sdhci_readb(host, SDHCI_UHS2_RESPONSE + 2);
+			if (resp & UHS2_RES_NACK_MASK) {
+				ecode = (resp >> UHS2_RES_ECODE_POS) & UHS2_RES_ECODE_MASK;
+				pr_err("%s: NACK is got, ECODE=0x%x.\n",
+				mmc_hostname(host->mmc), ecode);
+			}
+			bReadA0 = 1;
+		}
+	}
+
+	if (cmd->uhs2_resp &&
+	    cmd->uhs2_resp_len && cmd->uhs2_resp_len <= 20) {
+		/* Get whole response of some native CCMD, like
+		 * DEVICE_INIT, ENUMERATE.
+		 */
+		for (i = 0; i < cmd->uhs2_resp_len; i++)
+			cmd->uhs2_resp[i] = sdhci_readb(host, SDHCI_UHS2_RESPONSE + i);
+	} else {
+		/* Get SD CMD response and Payload for some read
+		 * CCMD, like INQUIRY_CFG.
+		 */
+		/* Per spec (p136), payload field is divided into
+		 * a unit of DWORD and transmission order within
+		 * a DWORD is big endian.
+		 */
+		if (!bReadA0)
+			sdhci_readl(host, SDHCI_UHS2_RESPONSE);
+		for (i = 4; i < 20; i += 4) {
+			cmd->resp[i / 4 - 1] =
+				(sdhci_readb(host,
+					     SDHCI_UHS2_RESPONSE + i) << 24) |
+				(sdhci_readb(host,
+					     SDHCI_UHS2_RESPONSE + i + 1)
+					<< 16) |
+				(sdhci_readb(host,
+					     SDHCI_UHS2_RESPONSE + i + 2)
+					<< 8) |
+				sdhci_readb(host, SDHCI_UHS2_RESPONSE + i + 3);
+		}
+	}
+}
+
+static void sdhci_uhs2_finish_command(struct sdhci_host *host)
+{
+	struct mmc_command *cmd = host->cmd;
+
+	__sdhci_uhs2_finish_command(host);
+
+	host->cmd = NULL;
+
+	if (cmd->mrq->cap_cmd_during_tfr && cmd == cmd->mrq->cmd)
+		mmc_command_done(host->mmc, cmd->mrq);
+
+	/*
+	 * The host can send and interrupt when the busy state has
+	 * ended, allowing us to wait without wasting CPU cycles.
+	 * The busy signal uses DAT0 so this is similar to waiting
+	 * for data to complete.
+	 *
+	 * Note: The 1.0 specification is a bit ambiguous about this
+	 *       feature so there might be some problems with older
+	 *       controllers.
+	 */
+	if (cmd->flags & MMC_RSP_BUSY) {
+		if (cmd->data) {
+			DBG("Cannot wait for busy signal when also doing a data transfer");
+		} else if (!(host->quirks & SDHCI_QUIRK_NO_BUSY_IRQ) &&
+			   cmd == host->data_cmd) {
+			/* Command complete before busy is ended */
+			return;
+		}
+	}
+
+	/* Processed actual command. */
+	if (host->data && host->data_early)
+		sdhci_uhs2_finish_data(host);
+
+	if (!cmd->data)
+		__sdhci_finish_mrq(host, cmd->mrq);
+}
+
+void sdhci_uhs2_request(struct mmc_host *mmc, struct mmc_request *mrq)
+{
+	struct sdhci_host *host = mmc_priv(mmc);
+	struct mmc_command *cmd;
+	unsigned long flags;
+	bool present;
+
+	if (!(sdhci_uhs2_mode(host))) {
+		sdhci_request(mmc, mrq);
+		return;
+	}
+
+	mrq->stop = NULL;
+	mrq->sbc = NULL;
+	if (mrq->data)
+		mrq->data->stop = NULL;
+
+	/* Firstly check card presence */
+	present = mmc->ops->get_cd(mmc);
+
+	spin_lock_irqsave(&host->lock, flags);
+
+	if (sdhci_present_error(host, mrq->cmd, present))
+		goto out_finish;
+
+	cmd = mrq->cmd;
+
+	if (!sdhci_uhs2_send_command(host, cmd))
+		goto out_finish;
+
+	spin_unlock_irqrestore(&host->lock, flags);
+
+	return;
+
+out_finish:
+	sdhci_finish_mrq(host, mrq);
+	spin_unlock_irqrestore(&host->lock, flags);
+}
+EXPORT_SYMBOL_GPL(sdhci_uhs2_request);
+
+int sdhci_uhs2_request_atomic(struct mmc_host *mmc, struct mmc_request *mrq)
+{
+	struct sdhci_host *host = mmc_priv(mmc);
+	struct mmc_command *cmd;
+	unsigned long flags;
+	int ret = 0;
+
+	if (!host->mmc->flags & MMC_UHS2_SUPPORT)
+		return sdhci_request_atomic(mmc, mrq);
+
+	spin_lock_irqsave(&host->lock, flags);
+
+	if (sdhci_present_error(host, mrq->cmd, true)) {
+		sdhci_finish_mrq(host, mrq);
+		goto out_finish;
+	}
+
+	cmd = mrq->cmd;
+
+	/*
+	 * The HSQ may send a command in interrupt context without polling
+	 * the busy signaling, which means we should return BUSY if controller
+	 * has not released inhibit bits to allow HSQ trying to send request
+	 * again in non-atomic context. So we should not finish this request
+	 * here.
+	 */
+	if (!sdhci_uhs2_send_command(host, cmd))
+		ret = -EBUSY;
+
+out_finish:
+	spin_unlock_irqrestore(&host->lock, flags);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(sdhci_uhs2_request_atomic);
+
 /*****************************************************************************\
  *                                                                           *
  * Driver init/exit                                                          *
@@ -581,6 +998,7 @@ static int sdhci_uhs2_host_ops_init(struct sdhci_host *host)
 		sdhci_uhs2_start_signal_voltage_switch;
 	host->mmc_host_ops.uhs2_set_ios = sdhci_uhs2_set_ios;
 	host->mmc_host_ops.uhs2_control = sdhci_uhs2_control;
+	host->mmc_host_ops.request = sdhci_uhs2_request;
 
 	return 0;
 }
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 3656e66fcca7..c547fc3b8b47 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -47,8 +47,6 @@
 static unsigned int debug_quirks = 0;
 static unsigned int debug_quirks2;
 
-static bool sdhci_send_command(struct sdhci_host *host, struct mmc_command *cmd);
-
 void sdhci_dumpregs(struct sdhci_host *host)
 {
 	SDHCI_DUMP("============ SDHCI REGISTER DUMP ===========\n");
@@ -147,10 +145,11 @@ void sdhci_enable_v4_mode(struct sdhci_host *host)
 }
 EXPORT_SYMBOL_GPL(sdhci_enable_v4_mode);
 
-static inline bool sdhci_data_line_cmd(struct mmc_command *cmd)
+bool sdhci_data_line_cmd(struct mmc_command *cmd)
 {
 	return cmd->data || cmd->flags & MMC_RSP_BUSY;
 }
+EXPORT_SYMBOL_GPL(sdhci_data_line_cmd);
 
 static void sdhci_set_card_detection(struct sdhci_host *host, bool enable)
 {
@@ -424,7 +423,7 @@ static void __sdhci_led_activate(struct sdhci_host *host)
 	sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
 }
 
-static void __sdhci_led_deactivate(struct sdhci_host *host)
+void __sdhci_led_deactivate(struct sdhci_host *host)
 {
 	u8 ctrl;
 
@@ -435,6 +434,7 @@ static void __sdhci_led_deactivate(struct sdhci_host *host)
 	ctrl &= ~SDHCI_CTRL_LED;
 	sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
 }
+EXPORT_SYMBOL_GPL(__sdhci_led_deactivate);
 
 #if IS_REACHABLE(CONFIG_LEDS_CLASS)
 static void sdhci_led_control(struct led_classdev *led,
@@ -513,14 +513,15 @@ static inline void sdhci_led_deactivate(struct sdhci_host *host)
 
 #endif
 
-static void sdhci_mod_timer(struct sdhci_host *host, struct mmc_request *mrq,
-			    unsigned long timeout)
+void sdhci_mod_timer(struct sdhci_host *host, struct mmc_request *mrq,
+		     unsigned long timeout)
 {
 	if (sdhci_data_line_cmd(mrq->cmd))
 		mod_timer(&host->data_timer, timeout);
 	else
 		mod_timer(&host->timer, timeout);
 }
+EXPORT_SYMBOL_GPL(sdhci_mod_timer);
 
 static void sdhci_del_timer(struct sdhci_host *host, struct mmc_request *mrq)
 {
@@ -1087,8 +1088,7 @@ static void sdhci_set_timeout(struct sdhci_host *host, struct mmc_command *cmd)
 		__sdhci_set_timeout(host, cmd);
 }
 
-static void sdhci_initialize_data(struct sdhci_host *host,
-				  struct mmc_data *data)
+void sdhci_initialize_data(struct sdhci_host *host, struct mmc_data *data)
 {
 	WARN_ON(host->data);
 
@@ -1101,6 +1101,7 @@ static void sdhci_initialize_data(struct sdhci_host *host,
 	host->data_early = 0;
 	host->data->bytes_xfered = 0;
 }
+EXPORT_SYMBOL_GPL(sdhci_initialize_data);
 
 static inline void sdhci_set_block_info(struct sdhci_host *host,
 					struct mmc_data *data)
@@ -1123,12 +1124,8 @@ static inline void sdhci_set_block_info(struct sdhci_host *host,
 	}
 }
 
-static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_command *cmd)
+void sdhci_prepare_dma(struct sdhci_host *host, struct mmc_data *data)
 {
-	struct mmc_data *data = cmd->data;
-
-	sdhci_initialize_data(host, data);
-
 	if (host->flags & (SDHCI_USE_SDMA | SDHCI_USE_ADMA)) {
 		struct scatterlist *sg;
 		unsigned int length_mask, offset_mask;
@@ -1213,6 +1210,16 @@ static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_command *cmd)
 	}
 
 	sdhci_set_transfer_irqs(host);
+}
+EXPORT_SYMBOL_GPL(sdhci_prepare_dma);
+
+static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_command *cmd)
+{
+	struct mmc_data *data = cmd->data;
+
+	sdhci_initialize_data(host, data);
+
+	sdhci_prepare_dma(host, data);
 
 	sdhci_set_block_info(host, data);
 }
@@ -1255,8 +1262,7 @@ static struct dma_chan *sdhci_external_dma_channel(struct sdhci_host *host,
 	return data->flags & MMC_DATA_WRITE ? host->tx_chan : host->rx_chan;
 }
 
-static int sdhci_external_dma_setup(struct sdhci_host *host,
-				    struct mmc_command *cmd)
+int sdhci_external_dma_setup(struct sdhci_host *host, struct mmc_command *cmd)
 {
 	int ret, i;
 	enum dma_transfer_direction dir;
@@ -1309,8 +1315,9 @@ static int sdhci_external_dma_setup(struct sdhci_host *host,
 
 	return ret;
 }
+EXPORT_SYMBOL_GPL(sdhci_external_dma_setup);
 
-static void sdhci_external_dma_release(struct sdhci_host *host)
+void sdhci_external_dma_release(struct sdhci_host *host)
 {
 	if (host->tx_chan) {
 		dma_release_channel(host->tx_chan);
@@ -1324,9 +1331,10 @@ static void sdhci_external_dma_release(struct sdhci_host *host)
 
 	sdhci_switch_external_dma(host, false);
 }
+EXPORT_SYMBOL_GPL(sdhci_external_dma_release);
 
-static void __sdhci_external_dma_prepare_data(struct sdhci_host *host,
-					      struct mmc_command *cmd)
+void __sdhci_external_dma_prepare_data(struct sdhci_host *host,
+				       struct mmc_command *cmd)
 {
 	struct mmc_data *data = cmd->data;
 
@@ -1337,6 +1345,7 @@ static void __sdhci_external_dma_prepare_data(struct sdhci_host *host,
 
 	sdhci_set_block_info(host, data);
 }
+EXPORT_SYMBOL(__sdhci_external_dma_prepare_data);
 
 static void sdhci_external_dma_prepare_data(struct sdhci_host *host,
 					    struct mmc_command *cmd)
@@ -1351,8 +1360,8 @@ static void sdhci_external_dma_prepare_data(struct sdhci_host *host,
 	}
 }
 
-static void sdhci_external_dma_pre_transfer(struct sdhci_host *host,
-					    struct mmc_command *cmd)
+void sdhci_external_dma_pre_transfer(struct sdhci_host *host,
+				     struct mmc_command *cmd)
 {
 	struct dma_chan *chan;
 
@@ -1363,6 +1372,7 @@ static void sdhci_external_dma_pre_transfer(struct sdhci_host *host,
 	if (chan)
 		dma_async_issue_pending(chan);
 }
+EXPORT_SYMBOL_GPL(sdhci_external_dma_pre_transfer);
 
 #else
 
@@ -1414,8 +1424,7 @@ static inline bool sdhci_auto_cmd23(struct sdhci_host *host,
 	return mrq->sbc && (host->flags & SDHCI_AUTO_CMD23);
 }
 
-static inline bool sdhci_manual_cmd23(struct sdhci_host *host,
-				      struct mmc_request *mrq)
+static inline bool sdhci_manual_cmd23(struct sdhci_host *host, struct mmc_request *mrq)
 {
 	return mrq->sbc && !(host->flags & SDHCI_AUTO_CMD23);
 }
@@ -1530,7 +1539,7 @@ static void sdhci_set_mrq_done(struct sdhci_host *host, struct mmc_request *mrq)
 	WARN_ON(i >= SDHCI_MAX_MRQS);
 }
 
-static void __sdhci_finish_mrq(struct sdhci_host *host, struct mmc_request *mrq)
+void __sdhci_finish_mrq(struct sdhci_host *host, struct mmc_request *mrq)
 {
 	if (host->cmd && host->cmd->mrq == mrq)
 		host->cmd = NULL;
@@ -1554,15 +1563,17 @@ static void __sdhci_finish_mrq(struct sdhci_host *host, struct mmc_request *mrq)
 	if (!sdhci_has_requests(host))
 		sdhci_led_deactivate(host);
 }
+EXPORT_SYMBOL_GPL(__sdhci_finish_mrq);
 
-static void sdhci_finish_mrq(struct sdhci_host *host, struct mmc_request *mrq)
+void sdhci_finish_mrq(struct sdhci_host *host, struct mmc_request *mrq)
 {
 	__sdhci_finish_mrq(host, mrq);
 
 	queue_work(host->complete_wq, &host->complete_work);
 }
+EXPORT_SYMBOL_GPL(sdhci_finish_mrq);
 
-static void __sdhci_finish_data(struct sdhci_host *host, bool sw_data_timeout)
+void __sdhci_finish_data_common(struct sdhci_host *host)
 {
 	struct mmc_command *data_cmd = host->data_cmd;
 	struct mmc_data *data = host->data;
@@ -1596,6 +1607,14 @@ static void __sdhci_finish_data(struct sdhci_host *host, bool sw_data_timeout)
 		data->bytes_xfered = 0;
 	else
 		data->bytes_xfered = data->blksz * data->blocks;
+}
+EXPORT_SYMBOL_GPL(__sdhci_finish_data_common);
+
+static void __sdhci_finish_data(struct sdhci_host *host, bool sw_data_timeout)
+{
+	struct mmc_data *data = host->data;
+
+	__sdhci_finish_data_common(host);
 
 	/*
 	 * Need to send CMD12 if -
@@ -1681,8 +1700,6 @@ static bool sdhci_send_command(struct sdhci_host *host, struct mmc_command *cmd)
 			sdhci_prepare_data(host, cmd);
 	}
 
-	sdhci_writel(host, cmd->arg, SDHCI_ARGUMENT);
-
 	sdhci_set_transfer_mode(host, cmd);
 
 	if ((cmd->flags & MMC_RSP_136) && (cmd->flags & MMC_RSP_BUSY)) {
@@ -1725,13 +1742,15 @@ static bool sdhci_send_command(struct sdhci_host *host, struct mmc_command *cmd)
 	if (host->use_external_dma)
 		sdhci_external_dma_pre_transfer(host, cmd);
 
+	sdhci_writel(host, cmd->arg, SDHCI_ARGUMENT);
+
 	sdhci_writew(host, SDHCI_MAKE_CMD(cmd->opcode, flags), SDHCI_COMMAND);
 
 	return true;
 }
 
-static bool sdhci_present_error(struct sdhci_host *host,
-				struct mmc_command *cmd, bool present)
+bool sdhci_present_error(struct sdhci_host *host,
+			 struct mmc_command *cmd, bool present)
 {
 	if (!present || host->flags & SDHCI_DEVICE_DEAD) {
 		cmd->error = -ENOMEDIUM;
@@ -1740,6 +1759,7 @@ static bool sdhci_present_error(struct sdhci_host *host,
 
 	return false;
 }
+EXPORT_SYMBOL_GPL(sdhci_present_error);
 
 static bool sdhci_send_command_retry(struct sdhci_host *host,
 				     struct mmc_command *cmd,
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index c2f989dc2361..3b87fcae1294 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -831,6 +831,20 @@ static inline void sdhci_read_caps(struct sdhci_host *host)
 	__sdhci_read_caps(host, NULL, NULL, NULL);
 }
 
+bool sdhci_data_line_cmd(struct mmc_command *cmd);
+void sdhci_mod_timer(struct sdhci_host *host, struct mmc_request *mrq, unsigned long timeout);
+void sdhci_initialize_data(struct sdhci_host *host, struct mmc_data *data);
+void sdhci_prepare_dma(struct sdhci_host *host, struct mmc_data *data);
+#if IS_ENABLED(CONFIG_MMC_SDHCI_EXTERNAL_DMA)
+int sdhci_external_dma_setup(struct sdhci_host *host, struct mmc_command *cmd);
+void sdhci_external_dma_release(struct sdhci_host *host);
+void __sdhci_external_dma_prepare_data(struct sdhci_host *host, struct mmc_command *cmd);
+void sdhci_external_dma_pre_transfer(struct sdhci_host *host, struct mmc_command *cmd);
+#endif
+void __sdhci_finish_mrq(struct sdhci_host *host, struct mmc_request *mrq);
+void sdhci_finish_mrq(struct sdhci_host *host, struct mmc_request *mrq);
+void __sdhci_finish_data_common(struct sdhci_host *host);
+bool sdhci_present_error(struct sdhci_host *host, struct mmc_command *cmd, bool present);
 u16 sdhci_calc_clk(struct sdhci_host *host, unsigned int clock,
 		   unsigned int *actual_clock);
 void sdhci_set_clock(struct sdhci_host *host, unsigned int clock);
-- 
2.25.1