Re: [PATCH V6 18/24] mmc: sdhci-uhs2: add request() and others

[Victor Shih <victorshihgli@gmail.com>]

Hi, Adrian

On Fri, Jan 6, 2023 at 5:29 AM Adrian Hunter <adrian.hunter@intel.com> wrote:
>
> On 13/12/22 11:00, Victor Shih wrote:
> > 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);
>
> Do not need to export __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);
>
> Do not need to export sdhci_external_dma_setup
>

I will update it in V7 version.

> >
> > -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);
>
> Do not need to export sdhci_external_dma_release
>

I will update it in V7 version.

> >
> > -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);
>
> Do not need to export __sdhci_external_dma_prepare_data
>

I will update it in V7 version.

> >
> >  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);
>
> Do not need to export sdhci_external_dma_pre_transfer
>

I will update it in V7 version.

> >
> >  #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)
>
> Please do not make whitespace changes if nothing else changes
>

I will update it in V7 version.

> >  {
> >       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);
>
> If this move of "sdhci_writel(host, cmd->arg, SDHCI_ARGUMENT)"
> is intentional, it should be a separate patch.
>

I will drop it and update in V7 version.

> > +
> >       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
>
> external_dma fns do not need export
>

I will update it in V7 version.

> > +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);
>

Thanks, Victor Shih