Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / mmc / core / core.c
diff --git a/kernel/drivers/mmc/core/core.c b/kernel/drivers/mmc/core/core.c
new file mode 100644 (file)
index 0000000..92e7671
--- /dev/null
@@ -0,0 +1,2753 @@
+/*
+ *  linux/drivers/mmc/core/core.c
+ *
+ *  Copyright (C) 2003-2004 Russell King, All Rights Reserved.
+ *  SD support Copyright (C) 2004 Ian Molton, All Rights Reserved.
+ *  Copyright (C) 2005-2008 Pierre Ossman, All Rights Reserved.
+ *  MMCv4 support Copyright (C) 2006 Philip Langdale, All Rights Reserved.
+ *
+ * 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/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/completion.h>
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/pagemap.h>
+#include <linux/err.h>
+#include <linux/leds.h>
+#include <linux/scatterlist.h>
+#include <linux/log2.h>
+#include <linux/regulator/consumer.h>
+#include <linux/pm_runtime.h>
+#include <linux/pm_wakeup.h>
+#include <linux/suspend.h>
+#include <linux/fault-inject.h>
+#include <linux/random.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+
+#include <linux/mmc/card.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/mmc.h>
+#include <linux/mmc/sd.h>
+#include <linux/mmc/slot-gpio.h>
+
+#include "core.h"
+#include "bus.h"
+#include "host.h"
+#include "sdio_bus.h"
+#include "pwrseq.h"
+
+#include "mmc_ops.h"
+#include "sd_ops.h"
+#include "sdio_ops.h"
+
+/* If the device is not responding */
+#define MMC_CORE_TIMEOUT_MS    (10 * 60 * 1000) /* 10 minute timeout */
+
+/*
+ * Background operations can take a long time, depending on the housekeeping
+ * operations the card has to perform.
+ */
+#define MMC_BKOPS_MAX_TIMEOUT  (4 * 60 * 1000) /* max time to wait in ms */
+
+static struct workqueue_struct *workqueue;
+static const unsigned freqs[] = { 400000, 300000, 200000, 100000 };
+
+/*
+ * Enabling software CRCs on the data blocks can be a significant (30%)
+ * performance cost, and for other reasons may not always be desired.
+ * So we allow it it to be disabled.
+ */
+bool use_spi_crc = 1;
+module_param(use_spi_crc, bool, 0);
+
+/*
+ * Internal function. Schedule delayed work in the MMC work queue.
+ */
+static int mmc_schedule_delayed_work(struct delayed_work *work,
+                                    unsigned long delay)
+{
+       return queue_delayed_work(workqueue, work, delay);
+}
+
+/*
+ * Internal function. Flush all scheduled work from the MMC work queue.
+ */
+static void mmc_flush_scheduled_work(void)
+{
+       flush_workqueue(workqueue);
+}
+
+#ifdef CONFIG_FAIL_MMC_REQUEST
+
+/*
+ * Internal function. Inject random data errors.
+ * If mmc_data is NULL no errors are injected.
+ */
+static void mmc_should_fail_request(struct mmc_host *host,
+                                   struct mmc_request *mrq)
+{
+       struct mmc_command *cmd = mrq->cmd;
+       struct mmc_data *data = mrq->data;
+       static const int data_errors[] = {
+               -ETIMEDOUT,
+               -EILSEQ,
+               -EIO,
+       };
+
+       if (!data)
+               return;
+
+       if (cmd->error || data->error ||
+           !should_fail(&host->fail_mmc_request, data->blksz * data->blocks))
+               return;
+
+       data->error = data_errors[prandom_u32() % ARRAY_SIZE(data_errors)];
+       data->bytes_xfered = (prandom_u32() % (data->bytes_xfered >> 9)) << 9;
+}
+
+#else /* CONFIG_FAIL_MMC_REQUEST */
+
+static inline void mmc_should_fail_request(struct mmc_host *host,
+                                          struct mmc_request *mrq)
+{
+}
+
+#endif /* CONFIG_FAIL_MMC_REQUEST */
+
+/**
+ *     mmc_request_done - finish processing an MMC request
+ *     @host: MMC host which completed request
+ *     @mrq: MMC request which request
+ *
+ *     MMC drivers should call this function when they have completed
+ *     their processing of a request.
+ */
+void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
+{
+       struct mmc_command *cmd = mrq->cmd;
+       int err = cmd->error;
+
+       if (err && cmd->retries && mmc_host_is_spi(host)) {
+               if (cmd->resp[0] & R1_SPI_ILLEGAL_COMMAND)
+                       cmd->retries = 0;
+       }
+
+       if (err && cmd->retries && !mmc_card_removed(host->card)) {
+               /*
+                * Request starter must handle retries - see
+                * mmc_wait_for_req_done().
+                */
+               if (mrq->done)
+                       mrq->done(mrq);
+       } else {
+               mmc_should_fail_request(host, mrq);
+
+               led_trigger_event(host->led, LED_OFF);
+
+               if (mrq->sbc) {
+                       pr_debug("%s: req done <CMD%u>: %d: %08x %08x %08x %08x\n",
+                               mmc_hostname(host), mrq->sbc->opcode,
+                               mrq->sbc->error,
+                               mrq->sbc->resp[0], mrq->sbc->resp[1],
+                               mrq->sbc->resp[2], mrq->sbc->resp[3]);
+               }
+
+               pr_debug("%s: req done (CMD%u): %d: %08x %08x %08x %08x\n",
+                       mmc_hostname(host), cmd->opcode, err,
+                       cmd->resp[0], cmd->resp[1],
+                       cmd->resp[2], cmd->resp[3]);
+
+               if (mrq->data) {
+                       pr_debug("%s:     %d bytes transferred: %d\n",
+                               mmc_hostname(host),
+                               mrq->data->bytes_xfered, mrq->data->error);
+               }
+
+               if (mrq->stop) {
+                       pr_debug("%s:     (CMD%u): %d: %08x %08x %08x %08x\n",
+                               mmc_hostname(host), mrq->stop->opcode,
+                               mrq->stop->error,
+                               mrq->stop->resp[0], mrq->stop->resp[1],
+                               mrq->stop->resp[2], mrq->stop->resp[3]);
+               }
+
+               if (mrq->done)
+                       mrq->done(mrq);
+
+               mmc_host_clk_release(host);
+       }
+}
+
+EXPORT_SYMBOL(mmc_request_done);
+
+static int mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
+{
+#ifdef CONFIG_MMC_DEBUG
+       unsigned int i, sz;
+       struct scatterlist *sg;
+#endif
+       if (mmc_card_removed(host->card))
+               return -ENOMEDIUM;
+
+       if (mrq->sbc) {
+               pr_debug("<%s: starting CMD%u arg %08x flags %08x>\n",
+                        mmc_hostname(host), mrq->sbc->opcode,
+                        mrq->sbc->arg, mrq->sbc->flags);
+       }
+
+       pr_debug("%s: starting CMD%u arg %08x flags %08x\n",
+                mmc_hostname(host), mrq->cmd->opcode,
+                mrq->cmd->arg, mrq->cmd->flags);
+
+       if (mrq->data) {
+               pr_debug("%s:     blksz %d blocks %d flags %08x "
+                       "tsac %d ms nsac %d\n",
+                       mmc_hostname(host), mrq->data->blksz,
+                       mrq->data->blocks, mrq->data->flags,
+                       mrq->data->timeout_ns / 1000000,
+                       mrq->data->timeout_clks);
+       }
+
+       if (mrq->stop) {
+               pr_debug("%s:     CMD%u arg %08x flags %08x\n",
+                        mmc_hostname(host), mrq->stop->opcode,
+                        mrq->stop->arg, mrq->stop->flags);
+       }
+
+       WARN_ON(!host->claimed);
+
+       mrq->cmd->error = 0;
+       mrq->cmd->mrq = mrq;
+       if (mrq->sbc) {
+               mrq->sbc->error = 0;
+               mrq->sbc->mrq = mrq;
+       }
+       if (mrq->data) {
+               BUG_ON(mrq->data->blksz > host->max_blk_size);
+               BUG_ON(mrq->data->blocks > host->max_blk_count);
+               BUG_ON(mrq->data->blocks * mrq->data->blksz >
+                       host->max_req_size);
+
+#ifdef CONFIG_MMC_DEBUG
+               sz = 0;
+               for_each_sg(mrq->data->sg, sg, mrq->data->sg_len, i)
+                       sz += sg->length;
+               BUG_ON(sz != mrq->data->blocks * mrq->data->blksz);
+#endif
+
+               mrq->cmd->data = mrq->data;
+               mrq->data->error = 0;
+               mrq->data->mrq = mrq;
+               if (mrq->stop) {
+                       mrq->data->stop = mrq->stop;
+                       mrq->stop->error = 0;
+                       mrq->stop->mrq = mrq;
+               }
+       }
+       mmc_host_clk_hold(host);
+       led_trigger_event(host->led, LED_FULL);
+       host->ops->request(host, mrq);
+
+       return 0;
+}
+
+/**
+ *     mmc_start_bkops - start BKOPS for supported cards
+ *     @card: MMC card to start BKOPS
+ *     @form_exception: A flag to indicate if this function was
+ *                      called due to an exception raised by the card
+ *
+ *     Start background operations whenever requested.
+ *     When the urgent BKOPS bit is set in a R1 command response
+ *     then background operations should be started immediately.
+*/
+void mmc_start_bkops(struct mmc_card *card, bool from_exception)
+{
+       int err;
+       int timeout;
+       bool use_busy_signal;
+
+       BUG_ON(!card);
+
+       if (!card->ext_csd.man_bkops_en || mmc_card_doing_bkops(card))
+               return;
+
+       err = mmc_read_bkops_status(card);
+       if (err) {
+               pr_err("%s: Failed to read bkops status: %d\n",
+                      mmc_hostname(card->host), err);
+               return;
+       }
+
+       if (!card->ext_csd.raw_bkops_status)
+               return;
+
+       if (card->ext_csd.raw_bkops_status < EXT_CSD_BKOPS_LEVEL_2 &&
+           from_exception)
+               return;
+
+       mmc_claim_host(card->host);
+       if (card->ext_csd.raw_bkops_status >= EXT_CSD_BKOPS_LEVEL_2) {
+               timeout = MMC_BKOPS_MAX_TIMEOUT;
+               use_busy_signal = true;
+       } else {
+               timeout = 0;
+               use_busy_signal = false;
+       }
+
+       err = __mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
+                       EXT_CSD_BKOPS_START, 1, timeout,
+                       use_busy_signal, true, false);
+       if (err) {
+               pr_warn("%s: Error %d starting bkops\n",
+                       mmc_hostname(card->host), err);
+               goto out;
+       }
+
+       /*
+        * For urgent bkops status (LEVEL_2 and more)
+        * bkops executed synchronously, otherwise
+        * the operation is in progress
+        */
+       if (!use_busy_signal)
+               mmc_card_set_doing_bkops(card);
+out:
+       mmc_release_host(card->host);
+}
+EXPORT_SYMBOL(mmc_start_bkops);
+
+/*
+ * mmc_wait_data_done() - done callback for data request
+ * @mrq: done data request
+ *
+ * Wakes up mmc context, passed as a callback to host controller driver
+ */
+static void mmc_wait_data_done(struct mmc_request *mrq)
+{
+       mrq->host->context_info.is_done_rcv = true;
+       wake_up_interruptible(&mrq->host->context_info.wait);
+}
+
+static void mmc_wait_done(struct mmc_request *mrq)
+{
+       complete(&mrq->completion);
+}
+
+/*
+ *__mmc_start_data_req() - starts data request
+ * @host: MMC host to start the request
+ * @mrq: data request to start
+ *
+ * Sets the done callback to be called when request is completed by the card.
+ * Starts data mmc request execution
+ */
+static int __mmc_start_data_req(struct mmc_host *host, struct mmc_request *mrq)
+{
+       int err;
+
+       mrq->done = mmc_wait_data_done;
+       mrq->host = host;
+
+       err = mmc_start_request(host, mrq);
+       if (err) {
+               mrq->cmd->error = err;
+               mmc_wait_data_done(mrq);
+       }
+
+       return err;
+}
+
+static int __mmc_start_req(struct mmc_host *host, struct mmc_request *mrq)
+{
+       int err;
+
+       init_completion(&mrq->completion);
+       mrq->done = mmc_wait_done;
+
+       err = mmc_start_request(host, mrq);
+       if (err) {
+               mrq->cmd->error = err;
+               complete(&mrq->completion);
+       }
+
+       return err;
+}
+
+/*
+ * mmc_wait_for_data_req_done() - wait for request completed
+ * @host: MMC host to prepare the command.
+ * @mrq: MMC request to wait for
+ *
+ * Blocks MMC context till host controller will ack end of data request
+ * execution or new request notification arrives from the block layer.
+ * Handles command retries.
+ *
+ * Returns enum mmc_blk_status after checking errors.
+ */
+static int mmc_wait_for_data_req_done(struct mmc_host *host,
+                                     struct mmc_request *mrq,
+                                     struct mmc_async_req *next_req)
+{
+       struct mmc_command *cmd;
+       struct mmc_context_info *context_info = &host->context_info;
+       int err;
+       unsigned long flags;
+
+       while (1) {
+               wait_event_interruptible(context_info->wait,
+                               (context_info->is_done_rcv ||
+                                context_info->is_new_req));
+               spin_lock_irqsave(&context_info->lock, flags);
+               context_info->is_waiting_last_req = false;
+               spin_unlock_irqrestore(&context_info->lock, flags);
+               if (context_info->is_done_rcv) {
+                       context_info->is_done_rcv = false;
+                       context_info->is_new_req = false;
+                       cmd = mrq->cmd;
+
+                       if (!cmd->error || !cmd->retries ||
+                           mmc_card_removed(host->card)) {
+                               err = host->areq->err_check(host->card,
+                                                           host->areq);
+                               break; /* return err */
+                       } else {
+                               pr_info("%s: req failed (CMD%u): %d, retrying...\n",
+                                       mmc_hostname(host),
+                                       cmd->opcode, cmd->error);
+                               cmd->retries--;
+                               cmd->error = 0;
+                               host->ops->request(host, mrq);
+                               continue; /* wait for done/new event again */
+                       }
+               } else if (context_info->is_new_req) {
+                       context_info->is_new_req = false;
+                       if (!next_req) {
+                               err = MMC_BLK_NEW_REQUEST;
+                               break; /* return err */
+                       }
+               }
+       }
+       return err;
+}
+
+static void mmc_wait_for_req_done(struct mmc_host *host,
+                                 struct mmc_request *mrq)
+{
+       struct mmc_command *cmd;
+
+       while (1) {
+               wait_for_completion(&mrq->completion);
+
+               cmd = mrq->cmd;
+
+               /*
+                * If host has timed out waiting for the sanitize
+                * to complete, card might be still in programming state
+                * so let's try to bring the card out of programming
+                * state.
+                */
+               if (cmd->sanitize_busy && cmd->error == -ETIMEDOUT) {
+                       if (!mmc_interrupt_hpi(host->card)) {
+                               pr_warn("%s: %s: Interrupted sanitize\n",
+                                       mmc_hostname(host), __func__);
+                               cmd->error = 0;
+                               break;
+                       } else {
+                               pr_err("%s: %s: Failed to interrupt sanitize\n",
+                                      mmc_hostname(host), __func__);
+                       }
+               }
+               if (!cmd->error || !cmd->retries ||
+                   mmc_card_removed(host->card))
+                       break;
+
+               pr_debug("%s: req failed (CMD%u): %d, retrying...\n",
+                        mmc_hostname(host), cmd->opcode, cmd->error);
+               cmd->retries--;
+               cmd->error = 0;
+               host->ops->request(host, mrq);
+       }
+}
+
+/**
+ *     mmc_pre_req - Prepare for a new request
+ *     @host: MMC host to prepare command
+ *     @mrq: MMC request to prepare for
+ *     @is_first_req: true if there is no previous started request
+ *                     that may run in parellel to this call, otherwise false
+ *
+ *     mmc_pre_req() is called in prior to mmc_start_req() to let
+ *     host prepare for the new request. Preparation of a request may be
+ *     performed while another request is running on the host.
+ */
+static void mmc_pre_req(struct mmc_host *host, struct mmc_request *mrq,
+                bool is_first_req)
+{
+       if (host->ops->pre_req) {
+               mmc_host_clk_hold(host);
+               host->ops->pre_req(host, mrq, is_first_req);
+               mmc_host_clk_release(host);
+       }
+}
+
+/**
+ *     mmc_post_req - Post process a completed request
+ *     @host: MMC host to post process command
+ *     @mrq: MMC request to post process for
+ *     @err: Error, if non zero, clean up any resources made in pre_req
+ *
+ *     Let the host post process a completed request. Post processing of
+ *     a request may be performed while another reuqest is running.
+ */
+static void mmc_post_req(struct mmc_host *host, struct mmc_request *mrq,
+                        int err)
+{
+       if (host->ops->post_req) {
+               mmc_host_clk_hold(host);
+               host->ops->post_req(host, mrq, err);
+               mmc_host_clk_release(host);
+       }
+}
+
+/**
+ *     mmc_start_req - start a non-blocking request
+ *     @host: MMC host to start command
+ *     @areq: async request to start
+ *     @error: out parameter returns 0 for success, otherwise non zero
+ *
+ *     Start a new MMC custom command request for a host.
+ *     If there is on ongoing async request wait for completion
+ *     of that request and start the new one and return.
+ *     Does not wait for the new request to complete.
+ *
+ *      Returns the completed request, NULL in case of none completed.
+ *     Wait for the an ongoing request (previoulsy started) to complete and
+ *     return the completed request. If there is no ongoing request, NULL
+ *     is returned without waiting. NULL is not an error condition.
+ */
+struct mmc_async_req *mmc_start_req(struct mmc_host *host,
+                                   struct mmc_async_req *areq, int *error)
+{
+       int err = 0;
+       int start_err = 0;
+       struct mmc_async_req *data = host->areq;
+
+       /* Prepare a new request */
+       if (areq)
+               mmc_pre_req(host, areq->mrq, !host->areq);
+
+       if (host->areq) {
+               err = mmc_wait_for_data_req_done(host, host->areq->mrq, areq);
+               if (err == MMC_BLK_NEW_REQUEST) {
+                       if (error)
+                               *error = err;
+                       /*
+                        * The previous request was not completed,
+                        * nothing to return
+                        */
+                       return NULL;
+               }
+               /*
+                * Check BKOPS urgency for each R1 response
+                */
+               if (host->card && mmc_card_mmc(host->card) &&
+                   ((mmc_resp_type(host->areq->mrq->cmd) == MMC_RSP_R1) ||
+                    (mmc_resp_type(host->areq->mrq->cmd) == MMC_RSP_R1B)) &&
+                   (host->areq->mrq->cmd->resp[0] & R1_EXCEPTION_EVENT)) {
+
+                       /* Cancel the prepared request */
+                       if (areq)
+                               mmc_post_req(host, areq->mrq, -EINVAL);
+
+                       mmc_start_bkops(host->card, true);
+
+                       /* prepare the request again */
+                       if (areq)
+                               mmc_pre_req(host, areq->mrq, !host->areq);
+               }
+       }
+
+       if (!err && areq)
+               start_err = __mmc_start_data_req(host, areq->mrq);
+
+       if (host->areq)
+               mmc_post_req(host, host->areq->mrq, 0);
+
+        /* Cancel a prepared request if it was not started. */
+       if ((err || start_err) && areq)
+               mmc_post_req(host, areq->mrq, -EINVAL);
+
+       if (err)
+               host->areq = NULL;
+       else
+               host->areq = areq;
+
+       if (error)
+               *error = err;
+       return data;
+}
+EXPORT_SYMBOL(mmc_start_req);
+
+/**
+ *     mmc_wait_for_req - start a request and wait for completion
+ *     @host: MMC host to start command
+ *     @mrq: MMC request to start
+ *
+ *     Start a new MMC custom command request for a host, and wait
+ *     for the command to complete. Does not attempt to parse the
+ *     response.
+ */
+void mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq)
+{
+       __mmc_start_req(host, mrq);
+       mmc_wait_for_req_done(host, mrq);
+}
+EXPORT_SYMBOL(mmc_wait_for_req);
+
+/**
+ *     mmc_interrupt_hpi - Issue for High priority Interrupt
+ *     @card: the MMC card associated with the HPI transfer
+ *
+ *     Issued High Priority Interrupt, and check for card status
+ *     until out-of prg-state.
+ */
+int mmc_interrupt_hpi(struct mmc_card *card)
+{
+       int err;
+       u32 status;
+       unsigned long prg_wait;
+
+       BUG_ON(!card);
+
+       if (!card->ext_csd.hpi_en) {
+               pr_info("%s: HPI enable bit unset\n", mmc_hostname(card->host));
+               return 1;
+       }
+
+       mmc_claim_host(card->host);
+       err = mmc_send_status(card, &status);
+       if (err) {
+               pr_err("%s: Get card status fail\n", mmc_hostname(card->host));
+               goto out;
+       }
+
+       switch (R1_CURRENT_STATE(status)) {
+       case R1_STATE_IDLE:
+       case R1_STATE_READY:
+       case R1_STATE_STBY:
+       case R1_STATE_TRAN:
+               /*
+                * In idle and transfer 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_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);
+       return err;
+}
+EXPORT_SYMBOL(mmc_interrupt_hpi);
+
+/**
+ *     mmc_wait_for_cmd - start a command and wait for completion
+ *     @host: MMC host to start command
+ *     @cmd: MMC command to start
+ *     @retries: maximum number of retries
+ *
+ *     Start a new MMC command for a host, and wait for the command
+ *     to complete.  Return any error that occurred while the command
+ *     was executing.  Do not attempt to parse the response.
+ */
+int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd, int retries)
+{
+       struct mmc_request mrq = {NULL};
+
+       WARN_ON(!host->claimed);
+
+       memset(cmd->resp, 0, sizeof(cmd->resp));
+       cmd->retries = retries;
+
+       mrq.cmd = cmd;
+       cmd->data = NULL;
+
+       mmc_wait_for_req(host, &mrq);
+
+       return cmd->error;
+}
+
+EXPORT_SYMBOL(mmc_wait_for_cmd);
+
+/**
+ *     mmc_stop_bkops - stop ongoing BKOPS
+ *     @card: MMC card to check BKOPS
+ *
+ *     Send HPI command to stop ongoing background operations to
+ *     allow rapid servicing of foreground operations, e.g. read/
+ *     writes. Wait until the card comes out of the programming state
+ *     to avoid errors in servicing read/write requests.
+ */
+int mmc_stop_bkops(struct mmc_card *card)
+{
+       int err = 0;
+
+       BUG_ON(!card);
+       err = mmc_interrupt_hpi(card);
+
+       /*
+        * If err is EINVAL, we can't issue an HPI.
+        * It should complete the BKOPS.
+        */
+       if (!err || (err == -EINVAL)) {
+               mmc_card_clr_doing_bkops(card);
+               err = 0;
+       }
+
+       return err;
+}
+EXPORT_SYMBOL(mmc_stop_bkops);
+
+int mmc_read_bkops_status(struct mmc_card *card)
+{
+       int err;
+       u8 *ext_csd;
+
+       mmc_claim_host(card->host);
+       err = mmc_get_ext_csd(card, &ext_csd);
+       mmc_release_host(card->host);
+       if (err)
+               return err;
+
+       card->ext_csd.raw_bkops_status = ext_csd[EXT_CSD_BKOPS_STATUS];
+       card->ext_csd.raw_exception_status = ext_csd[EXT_CSD_EXP_EVENTS_STATUS];
+       kfree(ext_csd);
+       return 0;
+}
+EXPORT_SYMBOL(mmc_read_bkops_status);
+
+/**
+ *     mmc_set_data_timeout - set the timeout for a data command
+ *     @data: data phase for command
+ *     @card: the MMC card associated with the data transfer
+ *
+ *     Computes the data timeout parameters according to the
+ *     correct algorithm given the card type.
+ */
+void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card)
+{
+       unsigned int mult;
+
+       /*
+        * SDIO cards only define an upper 1 s limit on access.
+        */
+       if (mmc_card_sdio(card)) {
+               data->timeout_ns = 1000000000;
+               data->timeout_clks = 0;
+               return;
+       }
+
+       /*
+        * SD cards use a 100 multiplier rather than 10
+        */
+       mult = mmc_card_sd(card) ? 100 : 10;
+
+       /*
+        * Scale up the multiplier (and therefore the timeout) by
+        * the r2w factor for writes.
+        */
+       if (data->flags & MMC_DATA_WRITE)
+               mult <<= card->csd.r2w_factor;
+
+       data->timeout_ns = card->csd.tacc_ns * mult;
+       data->timeout_clks = card->csd.tacc_clks * mult;
+
+       /*
+        * SD cards also have an upper limit on the timeout.
+        */
+       if (mmc_card_sd(card)) {
+               unsigned int timeout_us, limit_us;
+
+               timeout_us = data->timeout_ns / 1000;
+               if (mmc_host_clk_rate(card->host))
+                       timeout_us += data->timeout_clks * 1000 /
+                               (mmc_host_clk_rate(card->host) / 1000);
+
+               if (data->flags & MMC_DATA_WRITE)
+                       /*
+                        * The MMC spec "It is strongly recommended
+                        * for hosts to implement more than 500ms
+                        * timeout value even if the card indicates
+                        * the 250ms maximum busy length."  Even the
+                        * previous value of 300ms is known to be
+                        * insufficient for some cards.
+                        */
+                       limit_us = 3000000;
+               else
+                       limit_us = 100000;
+
+               /*
+                * SDHC cards always use these fixed values.
+                */
+               if (timeout_us > limit_us || mmc_card_blockaddr(card)) {
+                       data->timeout_ns = limit_us * 1000;
+                       data->timeout_clks = 0;
+               }
+
+               /* assign limit value if invalid */
+               if (timeout_us == 0)
+                       data->timeout_ns = limit_us * 1000;
+       }
+
+       /*
+        * Some cards require longer data read timeout than indicated in CSD.
+        * Address this by setting the read timeout to a "reasonably high"
+        * value. For the cards tested, 300ms has proven enough. If necessary,
+        * this value can be increased if other problematic cards require this.
+        */
+       if (mmc_card_long_read_time(card) && data->flags & MMC_DATA_READ) {
+               data->timeout_ns = 300000000;
+               data->timeout_clks = 0;
+       }
+
+       /*
+        * Some cards need very high timeouts if driven in SPI mode.
+        * The worst observed timeout was 900ms after writing a
+        * continuous stream of data until the internal logic
+        * overflowed.
+        */
+       if (mmc_host_is_spi(card->host)) {
+               if (data->flags & MMC_DATA_WRITE) {
+                       if (data->timeout_ns < 1000000000)
+                               data->timeout_ns = 1000000000;  /* 1s */
+               } else {
+                       if (data->timeout_ns < 100000000)
+                               data->timeout_ns =  100000000;  /* 100ms */
+               }
+       }
+}
+EXPORT_SYMBOL(mmc_set_data_timeout);
+
+/**
+ *     mmc_align_data_size - pads a transfer size to a more optimal value
+ *     @card: the MMC card associated with the data transfer
+ *     @sz: original transfer size
+ *
+ *     Pads the original data size with a number of extra bytes in
+ *     order to avoid controller bugs and/or performance hits
+ *     (e.g. some controllers revert to PIO for certain sizes).
+ *
+ *     Returns the improved size, which might be unmodified.
+ *
+ *     Note that this function is only relevant when issuing a
+ *     single scatter gather entry.
+ */
+unsigned int mmc_align_data_size(struct mmc_card *card, unsigned int sz)
+{
+       /*
+        * FIXME: We don't have a system for the controller to tell
+        * the core about its problems yet, so for now we just 32-bit
+        * align the size.
+        */
+       sz = ((sz + 3) / 4) * 4;
+
+       return sz;
+}
+EXPORT_SYMBOL(mmc_align_data_size);
+
+/**
+ *     __mmc_claim_host - exclusively claim a host
+ *     @host: mmc host to claim
+ *     @abort: whether or not the operation should be aborted
+ *
+ *     Claim a host for a set of operations.  If @abort is non null and
+ *     dereference a non-zero value then this will return prematurely with
+ *     that non-zero value without acquiring the lock.  Returns zero
+ *     with the lock held otherwise.
+ */
+int __mmc_claim_host(struct mmc_host *host, atomic_t *abort)
+{
+       DECLARE_WAITQUEUE(wait, current);
+       unsigned long flags;
+       int stop;
+       bool pm = false;
+
+       might_sleep();
+
+       add_wait_queue(&host->wq, &wait);
+       spin_lock_irqsave(&host->lock, flags);
+       while (1) {
+               set_current_state(TASK_UNINTERRUPTIBLE);
+               stop = abort ? atomic_read(abort) : 0;
+               if (stop || !host->claimed || host->claimer == current)
+                       break;
+               spin_unlock_irqrestore(&host->lock, flags);
+               schedule();
+               spin_lock_irqsave(&host->lock, flags);
+       }
+       set_current_state(TASK_RUNNING);
+       if (!stop) {
+               host->claimed = 1;
+               host->claimer = current;
+               host->claim_cnt += 1;
+               if (host->claim_cnt == 1)
+                       pm = true;
+       } else
+               wake_up(&host->wq);
+       spin_unlock_irqrestore(&host->lock, flags);
+       remove_wait_queue(&host->wq, &wait);
+
+       if (pm)
+               pm_runtime_get_sync(mmc_dev(host));
+
+       return stop;
+}
+EXPORT_SYMBOL(__mmc_claim_host);
+
+/**
+ *     mmc_release_host - release a host
+ *     @host: mmc host to release
+ *
+ *     Release a MMC host, allowing others to claim the host
+ *     for their operations.
+ */
+void mmc_release_host(struct mmc_host *host)
+{
+       unsigned long flags;
+
+       WARN_ON(!host->claimed);
+
+       spin_lock_irqsave(&host->lock, flags);
+       if (--host->claim_cnt) {
+               /* Release for nested claim */
+               spin_unlock_irqrestore(&host->lock, flags);
+       } else {
+               host->claimed = 0;
+               host->claimer = NULL;
+               spin_unlock_irqrestore(&host->lock, flags);
+               wake_up(&host->wq);
+               pm_runtime_mark_last_busy(mmc_dev(host));
+               pm_runtime_put_autosuspend(mmc_dev(host));
+       }
+}
+EXPORT_SYMBOL(mmc_release_host);
+
+/*
+ * This is a helper function, which fetches a runtime pm reference for the
+ * card device and also claims the host.
+ */
+void mmc_get_card(struct mmc_card *card)
+{
+       pm_runtime_get_sync(&card->dev);
+       mmc_claim_host(card->host);
+}
+EXPORT_SYMBOL(mmc_get_card);
+
+/*
+ * This is a helper function, which releases the host and drops the runtime
+ * pm reference for the card device.
+ */
+void mmc_put_card(struct mmc_card *card)
+{
+       mmc_release_host(card->host);
+       pm_runtime_mark_last_busy(&card->dev);
+       pm_runtime_put_autosuspend(&card->dev);
+}
+EXPORT_SYMBOL(mmc_put_card);
+
+/*
+ * Internal function that does the actual ios call to the host driver,
+ * optionally printing some debug output.
+ */
+static inline void mmc_set_ios(struct mmc_host *host)
+{
+       struct mmc_ios *ios = &host->ios;
+
+       pr_debug("%s: clock %uHz busmode %u powermode %u cs %u Vdd %u "
+               "width %u timing %u\n",
+                mmc_hostname(host), ios->clock, ios->bus_mode,
+                ios->power_mode, ios->chip_select, ios->vdd,
+                ios->bus_width, ios->timing);
+
+       if (ios->clock > 0)
+               mmc_set_ungated(host);
+       host->ops->set_ios(host, ios);
+}
+
+/*
+ * Control chip select pin on a host.
+ */
+void mmc_set_chip_select(struct mmc_host *host, int mode)
+{
+       mmc_host_clk_hold(host);
+       host->ios.chip_select = mode;
+       mmc_set_ios(host);
+       mmc_host_clk_release(host);
+}
+
+/*
+ * Sets the host clock to the highest possible frequency that
+ * is below "hz".
+ */
+static void __mmc_set_clock(struct mmc_host *host, unsigned int hz)
+{
+       WARN_ON(hz && hz < host->f_min);
+
+       if (hz > host->f_max)
+               hz = host->f_max;
+
+       host->ios.clock = hz;
+       mmc_set_ios(host);
+}
+
+void mmc_set_clock(struct mmc_host *host, unsigned int hz)
+{
+       mmc_host_clk_hold(host);
+       __mmc_set_clock(host, hz);
+       mmc_host_clk_release(host);
+}
+
+#ifdef CONFIG_MMC_CLKGATE
+/*
+ * This gates the clock by setting it to 0 Hz.
+ */
+void mmc_gate_clock(struct mmc_host *host)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&host->clk_lock, flags);
+       host->clk_old = host->ios.clock;
+       host->ios.clock = 0;
+       host->clk_gated = true;
+       spin_unlock_irqrestore(&host->clk_lock, flags);
+       mmc_set_ios(host);
+}
+
+/*
+ * This restores the clock from gating by using the cached
+ * clock value.
+ */
+void mmc_ungate_clock(struct mmc_host *host)
+{
+       /*
+        * We should previously have gated the clock, so the clock shall
+        * be 0 here! The clock may however be 0 during initialization,
+        * when some request operations are performed before setting
+        * the frequency. When ungate is requested in that situation
+        * we just ignore the call.
+        */
+       if (host->clk_old) {
+               BUG_ON(host->ios.clock);
+               /* This call will also set host->clk_gated to false */
+               __mmc_set_clock(host, host->clk_old);
+       }
+}
+
+void mmc_set_ungated(struct mmc_host *host)
+{
+       unsigned long flags;
+
+       /*
+        * We've been given a new frequency while the clock is gated,
+        * so make sure we regard this as ungating it.
+        */
+       spin_lock_irqsave(&host->clk_lock, flags);
+       host->clk_gated = false;
+       spin_unlock_irqrestore(&host->clk_lock, flags);
+}
+
+#else
+void mmc_set_ungated(struct mmc_host *host)
+{
+}
+#endif
+
+int mmc_execute_tuning(struct mmc_card *card)
+{
+       struct mmc_host *host = card->host;
+       u32 opcode;
+       int err;
+
+       if (!host->ops->execute_tuning)
+               return 0;
+
+       if (mmc_card_mmc(card))
+               opcode = MMC_SEND_TUNING_BLOCK_HS200;
+       else
+               opcode = MMC_SEND_TUNING_BLOCK;
+
+       mmc_host_clk_hold(host);
+       err = host->ops->execute_tuning(host, opcode);
+       mmc_host_clk_release(host);
+
+       if (err)
+               pr_err("%s: tuning execution failed\n", mmc_hostname(host));
+
+       return err;
+}
+
+/*
+ * Change the bus mode (open drain/push-pull) of a host.
+ */
+void mmc_set_bus_mode(struct mmc_host *host, unsigned int mode)
+{
+       mmc_host_clk_hold(host);
+       host->ios.bus_mode = mode;
+       mmc_set_ios(host);
+       mmc_host_clk_release(host);
+}
+
+/*
+ * Change data bus width of a host.
+ */
+void mmc_set_bus_width(struct mmc_host *host, unsigned int width)
+{
+       mmc_host_clk_hold(host);
+       host->ios.bus_width = width;
+       mmc_set_ios(host);
+       mmc_host_clk_release(host);
+}
+
+/*
+ * Set initial state after a power cycle or a hw_reset.
+ */
+void mmc_set_initial_state(struct mmc_host *host)
+{
+       if (mmc_host_is_spi(host))
+               host->ios.chip_select = MMC_CS_HIGH;
+       else
+               host->ios.chip_select = MMC_CS_DONTCARE;
+       host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
+       host->ios.bus_width = MMC_BUS_WIDTH_1;
+       host->ios.timing = MMC_TIMING_LEGACY;
+
+       mmc_set_ios(host);
+}
+
+/**
+ * mmc_vdd_to_ocrbitnum - Convert a voltage to the OCR bit number
+ * @vdd:       voltage (mV)
+ * @low_bits:  prefer low bits in boundary cases
+ *
+ * This function returns the OCR bit number according to the provided @vdd
+ * value. If conversion is not possible a negative errno value returned.
+ *
+ * Depending on the @low_bits flag the function prefers low or high OCR bits
+ * on boundary voltages. For example,
+ * with @low_bits = true, 3300 mV translates to ilog2(MMC_VDD_32_33);
+ * with @low_bits = false, 3300 mV translates to ilog2(MMC_VDD_33_34);
+ *
+ * Any value in the [1951:1999] range translates to the ilog2(MMC_VDD_20_21).
+ */
+static int mmc_vdd_to_ocrbitnum(int vdd, bool low_bits)
+{
+       const int max_bit = ilog2(MMC_VDD_35_36);
+       int bit;
+
+       if (vdd < 1650 || vdd > 3600)
+               return -EINVAL;
+
+       if (vdd >= 1650 && vdd <= 1950)
+               return ilog2(MMC_VDD_165_195);
+
+       if (low_bits)
+               vdd -= 1;
+
+       /* Base 2000 mV, step 100 mV, bit's base 8. */
+       bit = (vdd - 2000) / 100 + 8;
+       if (bit > max_bit)
+               return max_bit;
+       return bit;
+}
+
+/**
+ * mmc_vddrange_to_ocrmask - Convert a voltage range to the OCR mask
+ * @vdd_min:   minimum voltage value (mV)
+ * @vdd_max:   maximum voltage value (mV)
+ *
+ * This function returns the OCR mask bits according to the provided @vdd_min
+ * and @vdd_max values. If conversion is not possible the function returns 0.
+ *
+ * Notes wrt boundary cases:
+ * This function sets the OCR bits for all boundary voltages, for example
+ * [3300:3400] range is translated to MMC_VDD_32_33 | MMC_VDD_33_34 |
+ * MMC_VDD_34_35 mask.
+ */
+u32 mmc_vddrange_to_ocrmask(int vdd_min, int vdd_max)
+{
+       u32 mask = 0;
+
+       if (vdd_max < vdd_min)
+               return 0;
+
+       /* Prefer high bits for the boundary vdd_max values. */
+       vdd_max = mmc_vdd_to_ocrbitnum(vdd_max, false);
+       if (vdd_max < 0)
+               return 0;
+
+       /* Prefer low bits for the boundary vdd_min values. */
+       vdd_min = mmc_vdd_to_ocrbitnum(vdd_min, true);
+       if (vdd_min < 0)
+               return 0;
+
+       /* Fill the mask, from max bit to min bit. */
+       while (vdd_max >= vdd_min)
+               mask |= 1 << vdd_max--;
+
+       return mask;
+}
+EXPORT_SYMBOL(mmc_vddrange_to_ocrmask);
+
+#ifdef CONFIG_OF
+
+/**
+ * mmc_of_parse_voltage - return mask of supported voltages
+ * @np: The device node need to be parsed.
+ * @mask: mask of voltages available for MMC/SD/SDIO
+ *
+ * 1. Return zero on success.
+ * 2. Return negative errno: voltage-range is invalid.
+ */
+int mmc_of_parse_voltage(struct device_node *np, u32 *mask)
+{
+       const u32 *voltage_ranges;
+       int num_ranges, i;
+
+       voltage_ranges = of_get_property(np, "voltage-ranges", &num_ranges);
+       num_ranges = num_ranges / sizeof(*voltage_ranges) / 2;
+       if (!voltage_ranges || !num_ranges) {
+               pr_info("%s: voltage-ranges unspecified\n", np->full_name);
+               return -EINVAL;
+       }
+
+       for (i = 0; i < num_ranges; i++) {
+               const int j = i * 2;
+               u32 ocr_mask;
+
+               ocr_mask = mmc_vddrange_to_ocrmask(
+                               be32_to_cpu(voltage_ranges[j]),
+                               be32_to_cpu(voltage_ranges[j + 1]));
+               if (!ocr_mask) {
+                       pr_err("%s: voltage-range #%d is invalid\n",
+                               np->full_name, i);
+                       return -EINVAL;
+               }
+               *mask |= ocr_mask;
+       }
+
+       return 0;
+}
+EXPORT_SYMBOL(mmc_of_parse_voltage);
+
+#endif /* CONFIG_OF */
+
+static int mmc_of_get_func_num(struct device_node *node)
+{
+       u32 reg;
+       int ret;
+
+       ret = of_property_read_u32(node, "reg", &reg);
+       if (ret < 0)
+               return ret;
+
+       return reg;
+}
+
+struct device_node *mmc_of_find_child_device(struct mmc_host *host,
+               unsigned func_num)
+{
+       struct device_node *node;
+
+       if (!host->parent || !host->parent->of_node)
+               return NULL;
+
+       for_each_child_of_node(host->parent->of_node, node) {
+               if (mmc_of_get_func_num(node) == func_num)
+                       return node;
+       }
+
+       return NULL;
+}
+
+#ifdef CONFIG_REGULATOR
+
+/**
+ * mmc_regulator_get_ocrmask - return mask of supported voltages
+ * @supply: regulator to use
+ *
+ * This returns either a negative errno, or a mask of voltages that
+ * can be provided to MMC/SD/SDIO devices using the specified voltage
+ * regulator.  This would normally be called before registering the
+ * MMC host adapter.
+ */
+int mmc_regulator_get_ocrmask(struct regulator *supply)
+{
+       int                     result = 0;
+       int                     count;
+       int                     i;
+       int                     vdd_uV;
+       int                     vdd_mV;
+
+       count = regulator_count_voltages(supply);
+       if (count < 0)
+               return count;
+
+       for (i = 0; i < count; i++) {
+               vdd_uV = regulator_list_voltage(supply, i);
+               if (vdd_uV <= 0)
+                       continue;
+
+               vdd_mV = vdd_uV / 1000;
+               result |= mmc_vddrange_to_ocrmask(vdd_mV, vdd_mV);
+       }
+
+       if (!result) {
+               vdd_uV = regulator_get_voltage(supply);
+               if (vdd_uV <= 0)
+                       return vdd_uV;
+
+               vdd_mV = vdd_uV / 1000;
+               result = mmc_vddrange_to_ocrmask(vdd_mV, vdd_mV);
+       }
+
+       return result;
+}
+EXPORT_SYMBOL_GPL(mmc_regulator_get_ocrmask);
+
+/**
+ * mmc_regulator_set_ocr - set regulator to match host->ios voltage
+ * @mmc: the host to regulate
+ * @supply: regulator to use
+ * @vdd_bit: zero for power off, else a bit number (host->ios.vdd)
+ *
+ * Returns zero on success, else negative errno.
+ *
+ * MMC host drivers may use this to enable or disable a regulator using
+ * a particular supply voltage.  This would normally be called from the
+ * set_ios() method.
+ */
+int mmc_regulator_set_ocr(struct mmc_host *mmc,
+                       struct regulator *supply,
+                       unsigned short vdd_bit)
+{
+       int                     result = 0;
+       int                     min_uV, max_uV;
+
+       if (vdd_bit) {
+               int             tmp;
+
+               /*
+                * REVISIT mmc_vddrange_to_ocrmask() may have set some
+                * bits this regulator doesn't quite support ... don't
+                * be too picky, most cards and regulators are OK with
+                * a 0.1V range goof (it's a small error percentage).
+                */
+               tmp = vdd_bit - ilog2(MMC_VDD_165_195);
+               if (tmp == 0) {
+                       min_uV = 1650 * 1000;
+                       max_uV = 1950 * 1000;
+               } else {
+                       min_uV = 1900 * 1000 + tmp * 100 * 1000;
+                       max_uV = min_uV + 100 * 1000;
+               }
+
+               result = regulator_set_voltage(supply, min_uV, max_uV);
+               if (result == 0 && !mmc->regulator_enabled) {
+                       result = regulator_enable(supply);
+                       if (!result)
+                               mmc->regulator_enabled = true;
+               }
+       } else if (mmc->regulator_enabled) {
+               result = regulator_disable(supply);
+               if (result == 0)
+                       mmc->regulator_enabled = false;
+       }
+
+       if (result)
+               dev_err(mmc_dev(mmc),
+                       "could not set regulator OCR (%d)\n", result);
+       return result;
+}
+EXPORT_SYMBOL_GPL(mmc_regulator_set_ocr);
+
+#endif /* CONFIG_REGULATOR */
+
+int mmc_regulator_get_supply(struct mmc_host *mmc)
+{
+       struct device *dev = mmc_dev(mmc);
+       int ret;
+
+       mmc->supply.vmmc = devm_regulator_get_optional(dev, "vmmc");
+       mmc->supply.vqmmc = devm_regulator_get_optional(dev, "vqmmc");
+
+       if (IS_ERR(mmc->supply.vmmc)) {
+               if (PTR_ERR(mmc->supply.vmmc) == -EPROBE_DEFER)
+                       return -EPROBE_DEFER;
+               dev_info(dev, "No vmmc regulator found\n");
+       } else {
+               ret = mmc_regulator_get_ocrmask(mmc->supply.vmmc);
+               if (ret > 0)
+                       mmc->ocr_avail = ret;
+               else
+                       dev_warn(dev, "Failed getting OCR mask: %d\n", ret);
+       }
+
+       if (IS_ERR(mmc->supply.vqmmc)) {
+               if (PTR_ERR(mmc->supply.vqmmc) == -EPROBE_DEFER)
+                       return -EPROBE_DEFER;
+               dev_info(dev, "No vqmmc regulator found\n");
+       }
+
+       return 0;
+}
+EXPORT_SYMBOL_GPL(mmc_regulator_get_supply);
+
+/*
+ * Mask off any voltages we don't support and select
+ * the lowest voltage
+ */
+u32 mmc_select_voltage(struct mmc_host *host, u32 ocr)
+{
+       int bit;
+
+       /*
+        * Sanity check the voltages that the card claims to
+        * support.
+        */
+       if (ocr & 0x7F) {
+               dev_warn(mmc_dev(host),
+               "card claims to support voltages below defined range\n");
+               ocr &= ~0x7F;
+       }
+
+       ocr &= host->ocr_avail;
+       if (!ocr) {
+               dev_warn(mmc_dev(host), "no support for card's volts\n");
+               return 0;
+       }
+
+       if (host->caps2 & MMC_CAP2_FULL_PWR_CYCLE) {
+               bit = ffs(ocr) - 1;
+               ocr &= 3 << bit;
+               mmc_power_cycle(host, ocr);
+       } else {
+               bit = fls(ocr) - 1;
+               ocr &= 3 << bit;
+               if (bit != host->ios.vdd)
+                       dev_warn(mmc_dev(host), "exceeding card's volts\n");
+       }
+
+       return ocr;
+}
+
+int __mmc_set_signal_voltage(struct mmc_host *host, int signal_voltage)
+{
+       int err = 0;
+       int old_signal_voltage = host->ios.signal_voltage;
+
+       host->ios.signal_voltage = signal_voltage;
+       if (host->ops->start_signal_voltage_switch) {
+               mmc_host_clk_hold(host);
+               err = host->ops->start_signal_voltage_switch(host, &host->ios);
+               mmc_host_clk_release(host);
+       }
+
+       if (err)
+               host->ios.signal_voltage = old_signal_voltage;
+
+       return err;
+
+}
+
+int mmc_set_signal_voltage(struct mmc_host *host, int signal_voltage, u32 ocr)
+{
+       struct mmc_command cmd = {0};
+       int err = 0;
+       u32 clock;
+
+       BUG_ON(!host);
+
+       /*
+        * Send CMD11 only if the request is to switch the card to
+        * 1.8V signalling.
+        */
+       if (signal_voltage == MMC_SIGNAL_VOLTAGE_330)
+               return __mmc_set_signal_voltage(host, signal_voltage);
+
+       /*
+        * If we cannot switch voltages, return failure so the caller
+        * can continue without UHS mode
+        */
+       if (!host->ops->start_signal_voltage_switch)
+               return -EPERM;
+       if (!host->ops->card_busy)
+               pr_warn("%s: cannot verify signal voltage switch\n",
+                       mmc_hostname(host));
+
+       mmc_host_clk_hold(host);
+
+       cmd.opcode = SD_SWITCH_VOLTAGE;
+       cmd.arg = 0;
+       cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
+
+       err = mmc_wait_for_cmd(host, &cmd, 0);
+       if (err)
+               goto err_command;
+
+       if (!mmc_host_is_spi(host) && (cmd.resp[0] & R1_ERROR)) {
+               err = -EIO;
+               goto err_command;
+       }
+       /*
+        * The card should drive cmd and dat[0:3] low immediately
+        * after the response of cmd11, but wait 1 ms to be sure
+        */
+       mmc_delay(1);
+       if (host->ops->card_busy && !host->ops->card_busy(host)) {
+               err = -EAGAIN;
+               goto power_cycle;
+       }
+       /*
+        * During a signal voltage level switch, the clock must be gated
+        * for 5 ms according to the SD spec
+        */
+       clock = host->ios.clock;
+       host->ios.clock = 0;
+       mmc_set_ios(host);
+
+       if (__mmc_set_signal_voltage(host, signal_voltage)) {
+               /*
+                * Voltages may not have been switched, but we've already
+                * sent CMD11, so a power cycle is required anyway
+                */
+               err = -EAGAIN;
+               goto power_cycle;
+       }
+
+       /* Keep clock gated for at least 5 ms */
+       mmc_delay(5);
+       host->ios.clock = clock;
+       mmc_set_ios(host);
+
+       /* Wait for at least 1 ms according to spec */
+       mmc_delay(1);
+
+       /*
+        * Failure to switch is indicated by the card holding
+        * dat[0:3] low
+        */
+       if (host->ops->card_busy && host->ops->card_busy(host))
+               err = -EAGAIN;
+
+power_cycle:
+       if (err) {
+               pr_debug("%s: Signal voltage switch failed, "
+                       "power cycling card\n", mmc_hostname(host));
+               mmc_power_cycle(host, ocr);
+       }
+
+err_command:
+       mmc_host_clk_release(host);
+
+       return err;
+}
+
+/*
+ * Select timing parameters for host.
+ */
+void mmc_set_timing(struct mmc_host *host, unsigned int timing)
+{
+       mmc_host_clk_hold(host);
+       host->ios.timing = timing;
+       mmc_set_ios(host);
+       mmc_host_clk_release(host);
+}
+
+/*
+ * Select appropriate driver type for host.
+ */
+void mmc_set_driver_type(struct mmc_host *host, unsigned int drv_type)
+{
+       mmc_host_clk_hold(host);
+       host->ios.drv_type = drv_type;
+       mmc_set_ios(host);
+       mmc_host_clk_release(host);
+}
+
+/*
+ * Apply power to the MMC stack.  This is a two-stage process.
+ * First, we enable power to the card without the clock running.
+ * We then wait a bit for the power to stabilise.  Finally,
+ * enable the bus drivers and clock to the card.
+ *
+ * We must _NOT_ enable the clock prior to power stablising.
+ *
+ * If a host does all the power sequencing itself, ignore the
+ * initial MMC_POWER_UP stage.
+ */
+void mmc_power_up(struct mmc_host *host, u32 ocr)
+{
+       if (host->ios.power_mode == MMC_POWER_ON)
+               return;
+
+       mmc_host_clk_hold(host);
+
+       mmc_pwrseq_pre_power_on(host);
+
+       host->ios.vdd = fls(ocr) - 1;
+       host->ios.power_mode = MMC_POWER_UP;
+       /* Set initial state and call mmc_set_ios */
+       mmc_set_initial_state(host);
+
+       /* Try to set signal voltage to 3.3V but fall back to 1.8v or 1.2v */
+       if (__mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330) == 0)
+               dev_dbg(mmc_dev(host), "Initial signal voltage of 3.3v\n");
+       else if (__mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180) == 0)
+               dev_dbg(mmc_dev(host), "Initial signal voltage of 1.8v\n");
+       else if (__mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120) == 0)
+               dev_dbg(mmc_dev(host), "Initial signal voltage of 1.2v\n");
+
+       /*
+        * This delay should be sufficient to allow the power supply
+        * to reach the minimum voltage.
+        */
+       mmc_delay(10);
+
+       mmc_pwrseq_post_power_on(host);
+
+       host->ios.clock = host->f_init;
+
+       host->ios.power_mode = MMC_POWER_ON;
+       mmc_set_ios(host);
+
+       /*
+        * This delay must be at least 74 clock sizes, or 1 ms, or the
+        * time required to reach a stable voltage.
+        */
+       mmc_delay(10);
+
+       mmc_host_clk_release(host);
+}
+
+void mmc_power_off(struct mmc_host *host)
+{
+       if (host->ios.power_mode == MMC_POWER_OFF)
+               return;
+
+       mmc_host_clk_hold(host);
+
+       mmc_pwrseq_power_off(host);
+
+       host->ios.clock = 0;
+       host->ios.vdd = 0;
+
+       host->ios.power_mode = MMC_POWER_OFF;
+       /* Set initial state and call mmc_set_ios */
+       mmc_set_initial_state(host);
+
+       /*
+        * Some configurations, such as the 802.11 SDIO card in the OLPC
+        * XO-1.5, require a short delay after poweroff before the card
+        * can be successfully turned on again.
+        */
+       mmc_delay(1);
+
+       mmc_host_clk_release(host);
+}
+
+void mmc_power_cycle(struct mmc_host *host, u32 ocr)
+{
+       mmc_power_off(host);
+       /* Wait at least 1 ms according to SD spec */
+       mmc_delay(1);
+       mmc_power_up(host, ocr);
+}
+
+/*
+ * Cleanup when the last reference to the bus operator is dropped.
+ */
+static void __mmc_release_bus(struct mmc_host *host)
+{
+       BUG_ON(!host);
+       BUG_ON(host->bus_refs);
+       BUG_ON(!host->bus_dead);
+
+       host->bus_ops = NULL;
+}
+
+/*
+ * Increase reference count of bus operator
+ */
+static inline void mmc_bus_get(struct mmc_host *host)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&host->lock, flags);
+       host->bus_refs++;
+       spin_unlock_irqrestore(&host->lock, flags);
+}
+
+/*
+ * Decrease reference count of bus operator and free it if
+ * it is the last reference.
+ */
+static inline void mmc_bus_put(struct mmc_host *host)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&host->lock, flags);
+       host->bus_refs--;
+       if ((host->bus_refs == 0) && host->bus_ops)
+               __mmc_release_bus(host);
+       spin_unlock_irqrestore(&host->lock, flags);
+}
+
+/*
+ * Assign a mmc bus handler to a host. Only one bus handler may control a
+ * host at any given time.
+ */
+void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops)
+{
+       unsigned long flags;
+
+       BUG_ON(!host);
+       BUG_ON(!ops);
+
+       WARN_ON(!host->claimed);
+
+       spin_lock_irqsave(&host->lock, flags);
+
+       BUG_ON(host->bus_ops);
+       BUG_ON(host->bus_refs);
+
+       host->bus_ops = ops;
+       host->bus_refs = 1;
+       host->bus_dead = 0;
+
+       spin_unlock_irqrestore(&host->lock, flags);
+}
+
+/*
+ * Remove the current bus handler from a host.
+ */
+void mmc_detach_bus(struct mmc_host *host)
+{
+       unsigned long flags;
+
+       BUG_ON(!host);
+
+       WARN_ON(!host->claimed);
+       WARN_ON(!host->bus_ops);
+
+       spin_lock_irqsave(&host->lock, flags);
+
+       host->bus_dead = 1;
+
+       spin_unlock_irqrestore(&host->lock, flags);
+
+       mmc_bus_put(host);
+}
+
+static void _mmc_detect_change(struct mmc_host *host, unsigned long delay,
+                               bool cd_irq)
+{
+#ifdef CONFIG_MMC_DEBUG
+       unsigned long flags;
+       spin_lock_irqsave(&host->lock, flags);
+       WARN_ON(host->removed);
+       spin_unlock_irqrestore(&host->lock, flags);
+#endif
+
+       /*
+        * If the device is configured as wakeup, we prevent a new sleep for
+        * 5 s to give provision for user space to consume the event.
+        */
+       if (cd_irq && !(host->caps & MMC_CAP_NEEDS_POLL) &&
+               device_can_wakeup(mmc_dev(host)))
+               pm_wakeup_event(mmc_dev(host), 5000);
+
+       host->detect_change = 1;
+       mmc_schedule_delayed_work(&host->detect, delay);
+}
+
+/**
+ *     mmc_detect_change - process change of state on a MMC socket
+ *     @host: host which changed state.
+ *     @delay: optional delay to wait before detection (jiffies)
+ *
+ *     MMC drivers should call this when they detect a card has been
+ *     inserted or removed. The MMC layer will confirm that any
+ *     present card is still functional, and initialize any newly
+ *     inserted.
+ */
+void mmc_detect_change(struct mmc_host *host, unsigned long delay)
+{
+       _mmc_detect_change(host, delay, true);
+}
+EXPORT_SYMBOL(mmc_detect_change);
+
+void mmc_init_erase(struct mmc_card *card)
+{
+       unsigned int sz;
+
+       if (is_power_of_2(card->erase_size))
+               card->erase_shift = ffs(card->erase_size) - 1;
+       else
+               card->erase_shift = 0;
+
+       /*
+        * It is possible to erase an arbitrarily large area of an SD or MMC
+        * card.  That is not desirable because it can take a long time
+        * (minutes) potentially delaying more important I/O, and also the
+        * timeout calculations become increasingly hugely over-estimated.
+        * Consequently, 'pref_erase' is defined as a guide to limit erases
+        * to that size and alignment.
+        *
+        * For SD cards that define Allocation Unit size, limit erases to one
+        * Allocation Unit at a time.  For MMC cards that define High Capacity
+        * Erase Size, whether it is switched on or not, limit to that size.
+        * Otherwise just have a stab at a good value.  For modern cards it
+        * will end up being 4MiB.  Note that if the value is too small, it
+        * can end up taking longer to erase.
+        */
+       if (mmc_card_sd(card) && card->ssr.au) {
+               card->pref_erase = card->ssr.au;
+               card->erase_shift = ffs(card->ssr.au) - 1;
+       } else if (card->ext_csd.hc_erase_size) {
+               card->pref_erase = card->ext_csd.hc_erase_size;
+       } else if (card->erase_size) {
+               sz = (card->csd.capacity << (card->csd.read_blkbits - 9)) >> 11;
+               if (sz < 128)
+                       card->pref_erase = 512 * 1024 / 512;
+               else if (sz < 512)
+                       card->pref_erase = 1024 * 1024 / 512;
+               else if (sz < 1024)
+                       card->pref_erase = 2 * 1024 * 1024 / 512;
+               else
+                       card->pref_erase = 4 * 1024 * 1024 / 512;
+               if (card->pref_erase < card->erase_size)
+                       card->pref_erase = card->erase_size;
+               else {
+                       sz = card->pref_erase % card->erase_size;
+                       if (sz)
+                               card->pref_erase += card->erase_size - sz;
+               }
+       } else
+               card->pref_erase = 0;
+}
+
+static unsigned int mmc_mmc_erase_timeout(struct mmc_card *card,
+                                         unsigned int arg, unsigned int qty)
+{
+       unsigned int erase_timeout;
+
+       if (arg == MMC_DISCARD_ARG ||
+           (arg == MMC_TRIM_ARG && card->ext_csd.rev >= 6)) {
+               erase_timeout = card->ext_csd.trim_timeout;
+       } else if (card->ext_csd.erase_group_def & 1) {
+               /* High Capacity Erase Group Size uses HC timeouts */
+               if (arg == MMC_TRIM_ARG)
+                       erase_timeout = card->ext_csd.trim_timeout;
+               else
+                       erase_timeout = card->ext_csd.hc_erase_timeout;
+       } else {
+               /* CSD Erase Group Size uses write timeout */
+               unsigned int mult = (10 << card->csd.r2w_factor);
+               unsigned int timeout_clks = card->csd.tacc_clks * mult;
+               unsigned int timeout_us;
+
+               /* Avoid overflow: e.g. tacc_ns=80000000 mult=1280 */
+               if (card->csd.tacc_ns < 1000000)
+                       timeout_us = (card->csd.tacc_ns * mult) / 1000;
+               else
+                       timeout_us = (card->csd.tacc_ns / 1000) * mult;
+
+               /*
+                * ios.clock is only a target.  The real clock rate might be
+                * less but not that much less, so fudge it by multiplying by 2.
+                */
+               timeout_clks <<= 1;
+               timeout_us += (timeout_clks * 1000) /
+                             (mmc_host_clk_rate(card->host) / 1000);
+
+               erase_timeout = timeout_us / 1000;
+
+               /*
+                * Theoretically, the calculation could underflow so round up
+                * to 1ms in that case.
+                */
+               if (!erase_timeout)
+                       erase_timeout = 1;
+       }
+
+       /* Multiplier for secure operations */
+       if (arg & MMC_SECURE_ARGS) {
+               if (arg == MMC_SECURE_ERASE_ARG)
+                       erase_timeout *= card->ext_csd.sec_erase_mult;
+               else
+                       erase_timeout *= card->ext_csd.sec_trim_mult;
+       }
+
+       erase_timeout *= qty;
+
+       /*
+        * Ensure at least a 1 second timeout for SPI as per
+        * 'mmc_set_data_timeout()'
+        */
+       if (mmc_host_is_spi(card->host) && erase_timeout < 1000)
+               erase_timeout = 1000;
+
+       return erase_timeout;
+}
+
+static unsigned int mmc_sd_erase_timeout(struct mmc_card *card,
+                                        unsigned int arg,
+                                        unsigned int qty)
+{
+       unsigned int erase_timeout;
+
+       if (card->ssr.erase_timeout) {
+               /* Erase timeout specified in SD Status Register (SSR) */
+               erase_timeout = card->ssr.erase_timeout * qty +
+                               card->ssr.erase_offset;
+       } else {
+               /*
+                * Erase timeout not specified in SD Status Register (SSR) so
+                * use 250ms per write block.
+                */
+               erase_timeout = 250 * qty;
+       }
+
+       /* Must not be less than 1 second */
+       if (erase_timeout < 1000)
+               erase_timeout = 1000;
+
+       return erase_timeout;
+}
+
+static unsigned int mmc_erase_timeout(struct mmc_card *card,
+                                     unsigned int arg,
+                                     unsigned int qty)
+{
+       if (mmc_card_sd(card))
+               return mmc_sd_erase_timeout(card, arg, qty);
+       else
+               return mmc_mmc_erase_timeout(card, arg, qty);
+}
+
+static int mmc_do_erase(struct mmc_card *card, unsigned int from,
+                       unsigned int to, unsigned int arg)
+{
+       struct mmc_command cmd = {0};
+       unsigned int qty = 0;
+       unsigned long timeout;
+       int err;
+
+       /*
+        * qty is used to calculate the erase timeout which depends on how many
+        * erase groups (or allocation units in SD terminology) are affected.
+        * We count erasing part of an erase group as one erase group.
+        * For SD, the allocation units are always a power of 2.  For MMC, the
+        * erase group size is almost certainly also power of 2, but it does not
+        * seem to insist on that in the JEDEC standard, so we fall back to
+        * division in that case.  SD may not specify an allocation unit size,
+        * in which case the timeout is based on the number of write blocks.
+        *
+        * Note that the timeout for secure trim 2 will only be correct if the
+        * number of erase groups specified is the same as the total of all
+        * preceding secure trim 1 commands.  Since the power may have been
+        * lost since the secure trim 1 commands occurred, it is generally
+        * impossible to calculate the secure trim 2 timeout correctly.
+        */
+       if (card->erase_shift)
+               qty += ((to >> card->erase_shift) -
+                       (from >> card->erase_shift)) + 1;
+       else if (mmc_card_sd(card))
+               qty += to - from + 1;
+       else
+               qty += ((to / card->erase_size) -
+                       (from / card->erase_size)) + 1;
+
+       if (!mmc_card_blockaddr(card)) {
+               from <<= 9;
+               to <<= 9;
+       }
+
+       if (mmc_card_sd(card))
+               cmd.opcode = SD_ERASE_WR_BLK_START;
+       else
+               cmd.opcode = MMC_ERASE_GROUP_START;
+       cmd.arg = from;
+       cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
+       err = mmc_wait_for_cmd(card->host, &cmd, 0);
+       if (err) {
+               pr_err("mmc_erase: group start error %d, "
+                      "status %#x\n", err, cmd.resp[0]);
+               err = -EIO;
+               goto out;
+       }
+
+       memset(&cmd, 0, sizeof(struct mmc_command));
+       if (mmc_card_sd(card))
+               cmd.opcode = SD_ERASE_WR_BLK_END;
+       else
+               cmd.opcode = MMC_ERASE_GROUP_END;
+       cmd.arg = to;
+       cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
+       err = mmc_wait_for_cmd(card->host, &cmd, 0);
+       if (err) {
+               pr_err("mmc_erase: group end error %d, status %#x\n",
+                      err, cmd.resp[0]);
+               err = -EIO;
+               goto out;
+       }
+
+       memset(&cmd, 0, sizeof(struct mmc_command));
+       cmd.opcode = MMC_ERASE;
+       cmd.arg = arg;
+       cmd.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
+       cmd.busy_timeout = mmc_erase_timeout(card, arg, qty);
+       err = mmc_wait_for_cmd(card->host, &cmd, 0);
+       if (err) {
+               pr_err("mmc_erase: erase error %d, status %#x\n",
+                      err, cmd.resp[0]);
+               err = -EIO;
+               goto out;
+       }
+
+       if (mmc_host_is_spi(card->host))
+               goto out;
+
+       timeout = jiffies + msecs_to_jiffies(MMC_CORE_TIMEOUT_MS);
+       do {
+               memset(&cmd, 0, sizeof(struct mmc_command));
+               cmd.opcode = MMC_SEND_STATUS;
+               cmd.arg = card->rca << 16;
+               cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
+               /* Do not retry else we can't see errors */
+               err = mmc_wait_for_cmd(card->host, &cmd, 0);
+               if (err || (cmd.resp[0] & 0xFDF92000)) {
+                       pr_err("error %d requesting status %#x\n",
+                               err, cmd.resp[0]);
+                       err = -EIO;
+                       goto out;
+               }
+
+               /* Timeout if the device never becomes ready for data and
+                * never leaves the program state.
+                */
+               if (time_after(jiffies, timeout)) {
+                       pr_err("%s: Card stuck in programming state! %s\n",
+                               mmc_hostname(card->host), __func__);
+                       err =  -EIO;
+                       goto out;
+               }
+
+       } while (!(cmd.resp[0] & R1_READY_FOR_DATA) ||
+                (R1_CURRENT_STATE(cmd.resp[0]) == R1_STATE_PRG));
+out:
+       return err;
+}
+
+/**
+ * mmc_erase - erase sectors.
+ * @card: card to erase
+ * @from: first sector to erase
+ * @nr: number of sectors to erase
+ * @arg: erase command argument (SD supports only %MMC_ERASE_ARG)
+ *
+ * Caller must claim host before calling this function.
+ */
+int mmc_erase(struct mmc_card *card, unsigned int from, unsigned int nr,
+             unsigned int arg)
+{
+       unsigned int rem, to = from + nr;
+
+       if (!(card->host->caps & MMC_CAP_ERASE) ||
+           !(card->csd.cmdclass & CCC_ERASE))
+               return -EOPNOTSUPP;
+
+       if (!card->erase_size)
+               return -EOPNOTSUPP;
+
+       if (mmc_card_sd(card) && arg != MMC_ERASE_ARG)
+               return -EOPNOTSUPP;
+
+       if ((arg & MMC_SECURE_ARGS) &&
+           !(card->ext_csd.sec_feature_support & EXT_CSD_SEC_ER_EN))
+               return -EOPNOTSUPP;
+
+       if ((arg & MMC_TRIM_ARGS) &&
+           !(card->ext_csd.sec_feature_support & EXT_CSD_SEC_GB_CL_EN))
+               return -EOPNOTSUPP;
+
+       if (arg == MMC_SECURE_ERASE_ARG) {
+               if (from % card->erase_size || nr % card->erase_size)
+                       return -EINVAL;
+       }
+
+       if (arg == MMC_ERASE_ARG) {
+               rem = from % card->erase_size;
+               if (rem) {
+                       rem = card->erase_size - rem;
+                       from += rem;
+                       if (nr > rem)
+                               nr -= rem;
+                       else
+                               return 0;
+               }
+               rem = nr % card->erase_size;
+               if (rem)
+                       nr -= rem;
+       }
+
+       if (nr == 0)
+               return 0;
+
+       to = from + nr;
+
+       if (to <= from)
+               return -EINVAL;
+
+       /* 'from' and 'to' are inclusive */
+       to -= 1;
+
+       return mmc_do_erase(card, from, to, arg);
+}
+EXPORT_SYMBOL(mmc_erase);
+
+int mmc_can_erase(struct mmc_card *card)
+{
+       if ((card->host->caps & MMC_CAP_ERASE) &&
+           (card->csd.cmdclass & CCC_ERASE) && card->erase_size)
+               return 1;
+       return 0;
+}
+EXPORT_SYMBOL(mmc_can_erase);
+
+int mmc_can_trim(struct mmc_card *card)
+{
+       if (card->ext_csd.sec_feature_support & EXT_CSD_SEC_GB_CL_EN)
+               return 1;
+       return 0;
+}
+EXPORT_SYMBOL(mmc_can_trim);
+
+int mmc_can_discard(struct mmc_card *card)
+{
+       /*
+        * As there's no way to detect the discard support bit at v4.5
+        * use the s/w feature support filed.
+        */
+       if (card->ext_csd.feature_support & MMC_DISCARD_FEATURE)
+               return 1;
+       return 0;
+}
+EXPORT_SYMBOL(mmc_can_discard);
+
+int mmc_can_sanitize(struct mmc_card *card)
+{
+       if (!mmc_can_trim(card) && !mmc_can_erase(card))
+               return 0;
+       if (card->ext_csd.sec_feature_support & EXT_CSD_SEC_SANITIZE)
+               return 1;
+       return 0;
+}
+EXPORT_SYMBOL(mmc_can_sanitize);
+
+int mmc_can_secure_erase_trim(struct mmc_card *card)
+{
+       if ((card->ext_csd.sec_feature_support & EXT_CSD_SEC_ER_EN) &&
+           !(card->quirks & MMC_QUIRK_SEC_ERASE_TRIM_BROKEN))
+               return 1;
+       return 0;
+}
+EXPORT_SYMBOL(mmc_can_secure_erase_trim);
+
+int mmc_erase_group_aligned(struct mmc_card *card, unsigned int from,
+                           unsigned int nr)
+{
+       if (!card->erase_size)
+               return 0;
+       if (from % card->erase_size || nr % card->erase_size)
+               return 0;
+       return 1;
+}
+EXPORT_SYMBOL(mmc_erase_group_aligned);
+
+static unsigned int mmc_do_calc_max_discard(struct mmc_card *card,
+                                           unsigned int arg)
+{
+       struct mmc_host *host = card->host;
+       unsigned int max_discard, x, y, qty = 0, max_qty, timeout;
+       unsigned int last_timeout = 0;
+
+       if (card->erase_shift)
+               max_qty = UINT_MAX >> card->erase_shift;
+       else if (mmc_card_sd(card))
+               max_qty = UINT_MAX;
+       else
+               max_qty = UINT_MAX / card->erase_size;
+
+       /* Find the largest qty with an OK timeout */
+       do {
+               y = 0;
+               for (x = 1; x && x <= max_qty && max_qty - x >= qty; x <<= 1) {
+                       timeout = mmc_erase_timeout(card, arg, qty + x);
+                       if (timeout > host->max_busy_timeout)
+                               break;
+                       if (timeout < last_timeout)
+                               break;
+                       last_timeout = timeout;
+                       y = x;
+               }
+               qty += y;
+       } while (y);
+
+       if (!qty)
+               return 0;
+
+       if (qty == 1)
+               return 1;
+
+       /* Convert qty to sectors */
+       if (card->erase_shift)
+               max_discard = --qty << card->erase_shift;
+       else if (mmc_card_sd(card))
+               max_discard = qty;
+       else
+               max_discard = --qty * card->erase_size;
+
+       return max_discard;
+}
+
+unsigned int mmc_calc_max_discard(struct mmc_card *card)
+{
+       struct mmc_host *host = card->host;
+       unsigned int max_discard, max_trim;
+
+       if (!host->max_busy_timeout)
+               return UINT_MAX;
+
+       /*
+        * Without erase_group_def set, MMC erase timeout depends on clock
+        * frequence which can change.  In that case, the best choice is
+        * just the preferred erase size.
+        */
+       if (mmc_card_mmc(card) && !(card->ext_csd.erase_group_def & 1))
+               return card->pref_erase;
+
+       max_discard = mmc_do_calc_max_discard(card, MMC_ERASE_ARG);
+       if (mmc_can_trim(card)) {
+               max_trim = mmc_do_calc_max_discard(card, MMC_TRIM_ARG);
+               if (max_trim < max_discard)
+                       max_discard = max_trim;
+       } else if (max_discard < card->erase_size) {
+               max_discard = 0;
+       }
+       pr_debug("%s: calculated max. discard sectors %u for timeout %u ms\n",
+                mmc_hostname(host), max_discard, host->max_busy_timeout);
+       return max_discard;
+}
+EXPORT_SYMBOL(mmc_calc_max_discard);
+
+int mmc_set_blocklen(struct mmc_card *card, unsigned int blocklen)
+{
+       struct mmc_command cmd = {0};
+
+       if (mmc_card_blockaddr(card) || mmc_card_ddr52(card))
+               return 0;
+
+       cmd.opcode = MMC_SET_BLOCKLEN;
+       cmd.arg = blocklen;
+       cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
+       return mmc_wait_for_cmd(card->host, &cmd, 5);
+}
+EXPORT_SYMBOL(mmc_set_blocklen);
+
+int mmc_set_blockcount(struct mmc_card *card, unsigned int blockcount,
+                       bool is_rel_write)
+{
+       struct mmc_command cmd = {0};
+
+       cmd.opcode = MMC_SET_BLOCK_COUNT;
+       cmd.arg = blockcount & 0x0000FFFF;
+       if (is_rel_write)
+               cmd.arg |= 1 << 31;
+       cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
+       return mmc_wait_for_cmd(card->host, &cmd, 5);
+}
+EXPORT_SYMBOL(mmc_set_blockcount);
+
+static void mmc_hw_reset_for_init(struct mmc_host *host)
+{
+       if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
+               return;
+       mmc_host_clk_hold(host);
+       host->ops->hw_reset(host);
+       mmc_host_clk_release(host);
+}
+
+int mmc_hw_reset(struct mmc_host *host)
+{
+       int ret;
+
+       if (!host->card)
+               return -EINVAL;
+
+       mmc_bus_get(host);
+       if (!host->bus_ops || host->bus_dead || !host->bus_ops->reset) {
+               mmc_bus_put(host);
+               return -EOPNOTSUPP;
+       }
+
+       ret = host->bus_ops->reset(host);
+       mmc_bus_put(host);
+
+       pr_warn("%s: tried to reset card\n", mmc_hostname(host));
+
+       return ret;
+}
+EXPORT_SYMBOL(mmc_hw_reset);
+
+static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
+{
+       host->f_init = freq;
+
+#ifdef CONFIG_MMC_DEBUG
+       pr_info("%s: %s: trying to init card at %u Hz\n",
+               mmc_hostname(host), __func__, host->f_init);
+#endif
+       mmc_power_up(host, host->ocr_avail);
+
+       /*
+        * Some eMMCs (with VCCQ always on) may not be reset after power up, so
+        * do a hardware reset if possible.
+        */
+       mmc_hw_reset_for_init(host);
+
+       /*
+        * sdio_reset sends CMD52 to reset card.  Since we do not know
+        * if the card is being re-initialized, just send it.  CMD52
+        * should be ignored by SD/eMMC cards.
+        */
+       sdio_reset(host);
+       mmc_go_idle(host);
+
+       mmc_send_if_cond(host, host->ocr_avail);
+
+       /* Order's important: probe SDIO, then SD, then MMC */
+       if (!mmc_attach_sdio(host))
+               return 0;
+       if (!mmc_attach_sd(host))
+               return 0;
+       if (!mmc_attach_mmc(host))
+               return 0;
+
+       mmc_power_off(host);
+       return -EIO;
+}
+
+int _mmc_detect_card_removed(struct mmc_host *host)
+{
+       int ret;
+
+       if (host->caps & MMC_CAP_NONREMOVABLE)
+               return 0;
+
+       if (!host->card || mmc_card_removed(host->card))
+               return 1;
+
+       ret = host->bus_ops->alive(host);
+
+       /*
+        * Card detect status and alive check may be out of sync if card is
+        * removed slowly, when card detect switch changes while card/slot
+        * pads are still contacted in hardware (refer to "SD Card Mechanical
+        * Addendum, Appendix C: Card Detection Switch"). So reschedule a
+        * detect work 200ms later for this case.
+        */
+       if (!ret && host->ops->get_cd && !host->ops->get_cd(host)) {
+               mmc_detect_change(host, msecs_to_jiffies(200));
+               pr_debug("%s: card removed too slowly\n", mmc_hostname(host));
+       }
+
+       if (ret) {
+               mmc_card_set_removed(host->card);
+               pr_debug("%s: card remove detected\n", mmc_hostname(host));
+       }
+
+       return ret;
+}
+
+int mmc_detect_card_removed(struct mmc_host *host)
+{
+       struct mmc_card *card = host->card;
+       int ret;
+
+       WARN_ON(!host->claimed);
+
+       if (!card)
+               return 1;
+
+       ret = mmc_card_removed(card);
+       /*
+        * The card will be considered unchanged unless we have been asked to
+        * detect a change or host requires polling to provide card detection.
+        */
+       if (!host->detect_change && !(host->caps & MMC_CAP_NEEDS_POLL))
+               return ret;
+
+       host->detect_change = 0;
+       if (!ret) {
+               ret = _mmc_detect_card_removed(host);
+               if (ret && (host->caps & MMC_CAP_NEEDS_POLL)) {
+                       /*
+                        * Schedule a detect work as soon as possible to let a
+                        * rescan handle the card removal.
+                        */
+                       cancel_delayed_work(&host->detect);
+                       _mmc_detect_change(host, 0, false);
+               }
+       }
+
+       return ret;
+}
+EXPORT_SYMBOL(mmc_detect_card_removed);
+
+void mmc_rescan(struct work_struct *work)
+{
+       struct mmc_host *host =
+               container_of(work, struct mmc_host, detect.work);
+       int i;
+
+       if (host->trigger_card_event && host->ops->card_event) {
+               host->ops->card_event(host);
+               host->trigger_card_event = false;
+       }
+
+       if (host->rescan_disable)
+               return;
+
+       /* If there is a non-removable card registered, only scan once */
+       if ((host->caps & MMC_CAP_NONREMOVABLE) && host->rescan_entered)
+               return;
+       host->rescan_entered = 1;
+
+       mmc_bus_get(host);
+
+       /*
+        * if there is a _removable_ card registered, check whether it is
+        * still present
+        */
+       if (host->bus_ops && !host->bus_dead
+           && !(host->caps & MMC_CAP_NONREMOVABLE))
+               host->bus_ops->detect(host);
+
+       host->detect_change = 0;
+
+       /*
+        * Let mmc_bus_put() free the bus/bus_ops if we've found that
+        * the card is no longer present.
+        */
+       mmc_bus_put(host);
+       mmc_bus_get(host);
+
+       /* if there still is a card present, stop here */
+       if (host->bus_ops != NULL) {
+               mmc_bus_put(host);
+               goto out;
+       }
+
+       /*
+        * Only we can add a new handler, so it's safe to
+        * release the lock here.
+        */
+       mmc_bus_put(host);
+
+       if (!(host->caps & MMC_CAP_NONREMOVABLE) && host->ops->get_cd &&
+                       host->ops->get_cd(host) == 0) {
+               mmc_claim_host(host);
+               mmc_power_off(host);
+               mmc_release_host(host);
+               goto out;
+       }
+
+       mmc_claim_host(host);
+       for (i = 0; i < ARRAY_SIZE(freqs); i++) {
+               if (!mmc_rescan_try_freq(host, max(freqs[i], host->f_min)))
+                       break;
+               if (freqs[i] <= host->f_min)
+                       break;
+       }
+       mmc_release_host(host);
+
+ out:
+       if (host->caps & MMC_CAP_NEEDS_POLL)
+               mmc_schedule_delayed_work(&host->detect, HZ);
+}
+
+void mmc_start_host(struct mmc_host *host)
+{
+       host->f_init = max(freqs[0], host->f_min);
+       host->rescan_disable = 0;
+       host->ios.power_mode = MMC_POWER_UNDEFINED;
+       if (host->caps2 & MMC_CAP2_NO_PRESCAN_POWERUP)
+               mmc_power_off(host);
+       else
+               mmc_power_up(host, host->ocr_avail);
+       mmc_gpiod_request_cd_irq(host);
+       _mmc_detect_change(host, 0, false);
+}
+
+void mmc_stop_host(struct mmc_host *host)
+{
+#ifdef CONFIG_MMC_DEBUG
+       unsigned long flags;
+       spin_lock_irqsave(&host->lock, flags);
+       host->removed = 1;
+       spin_unlock_irqrestore(&host->lock, flags);
+#endif
+       if (host->slot.cd_irq >= 0)
+               disable_irq(host->slot.cd_irq);
+
+       host->rescan_disable = 1;
+       cancel_delayed_work_sync(&host->detect);
+       mmc_flush_scheduled_work();
+
+       /* clear pm flags now and let card drivers set them as needed */
+       host->pm_flags = 0;
+
+       mmc_bus_get(host);
+       if (host->bus_ops && !host->bus_dead) {
+               /* Calling bus_ops->remove() with a claimed host can deadlock */
+               host->bus_ops->remove(host);
+               mmc_claim_host(host);
+               mmc_detach_bus(host);
+               mmc_power_off(host);
+               mmc_release_host(host);
+               mmc_bus_put(host);
+               return;
+       }
+       mmc_bus_put(host);
+
+       BUG_ON(host->card);
+
+       mmc_power_off(host);
+}
+
+int mmc_power_save_host(struct mmc_host *host)
+{
+       int ret = 0;
+
+#ifdef CONFIG_MMC_DEBUG
+       pr_info("%s: %s: powering down\n", mmc_hostname(host), __func__);
+#endif
+
+       mmc_bus_get(host);
+
+       if (!host->bus_ops || host->bus_dead) {
+               mmc_bus_put(host);
+               return -EINVAL;
+       }
+
+       if (host->bus_ops->power_save)
+               ret = host->bus_ops->power_save(host);
+
+       mmc_bus_put(host);
+
+       mmc_power_off(host);
+
+       return ret;
+}
+EXPORT_SYMBOL(mmc_power_save_host);
+
+int mmc_power_restore_host(struct mmc_host *host)
+{
+       int ret;
+
+#ifdef CONFIG_MMC_DEBUG
+       pr_info("%s: %s: powering up\n", mmc_hostname(host), __func__);
+#endif
+
+       mmc_bus_get(host);
+
+       if (!host->bus_ops || host->bus_dead) {
+               mmc_bus_put(host);
+               return -EINVAL;
+       }
+
+       mmc_power_up(host, host->card->ocr);
+       ret = host->bus_ops->power_restore(host);
+
+       mmc_bus_put(host);
+
+       return ret;
+}
+EXPORT_SYMBOL(mmc_power_restore_host);
+
+/*
+ * Flush the cache to the non-volatile storage.
+ */
+int mmc_flush_cache(struct mmc_card *card)
+{
+       int err = 0;
+
+       if (mmc_card_mmc(card) &&
+                       (card->ext_csd.cache_size > 0) &&
+                       (card->ext_csd.cache_ctrl & 1)) {
+               err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
+                               EXT_CSD_FLUSH_CACHE, 1, 0);
+               if (err)
+                       pr_err("%s: cache flush error %d\n",
+                                       mmc_hostname(card->host), err);
+       }
+
+       return err;
+}
+EXPORT_SYMBOL(mmc_flush_cache);
+
+#ifdef CONFIG_PM
+
+/* Do the card removal on suspend if card is assumed removeable
+ * Do that in pm notifier while userspace isn't yet frozen, so we will be able
+   to sync the card.
+*/
+int mmc_pm_notify(struct notifier_block *notify_block,
+                                       unsigned long mode, void *unused)
+{
+       struct mmc_host *host = container_of(
+               notify_block, struct mmc_host, pm_notify);
+       unsigned long flags;
+       int err = 0;
+
+       switch (mode) {
+       case PM_HIBERNATION_PREPARE:
+       case PM_SUSPEND_PREPARE:
+       case PM_RESTORE_PREPARE:
+               spin_lock_irqsave(&host->lock, flags);
+               host->rescan_disable = 1;
+               spin_unlock_irqrestore(&host->lock, flags);
+               cancel_delayed_work_sync(&host->detect);
+
+               if (!host->bus_ops)
+                       break;
+
+               /* Validate prerequisites for suspend */
+               if (host->bus_ops->pre_suspend)
+                       err = host->bus_ops->pre_suspend(host);
+               if (!err)
+                       break;
+
+               /* Calling bus_ops->remove() with a claimed host can deadlock */
+               host->bus_ops->remove(host);
+               mmc_claim_host(host);
+               mmc_detach_bus(host);
+               mmc_power_off(host);
+               mmc_release_host(host);
+               host->pm_flags = 0;
+               break;
+
+       case PM_POST_SUSPEND:
+       case PM_POST_HIBERNATION:
+       case PM_POST_RESTORE:
+
+               spin_lock_irqsave(&host->lock, flags);
+               host->rescan_disable = 0;
+               spin_unlock_irqrestore(&host->lock, flags);
+               _mmc_detect_change(host, 0, false);
+
+       }
+
+       return 0;
+}
+#endif
+
+/**
+ * mmc_init_context_info() - init synchronization context
+ * @host: mmc host
+ *
+ * Init struct context_info needed to implement asynchronous
+ * request mechanism, used by mmc core, host driver and mmc requests
+ * supplier.
+ */
+void mmc_init_context_info(struct mmc_host *host)
+{
+       spin_lock_init(&host->context_info.lock);
+       host->context_info.is_new_req = false;
+       host->context_info.is_done_rcv = false;
+       host->context_info.is_waiting_last_req = false;
+       init_waitqueue_head(&host->context_info.wait);
+}
+
+static int __init mmc_init(void)
+{
+       int ret;
+
+       workqueue = alloc_ordered_workqueue("kmmcd", 0);
+       if (!workqueue)
+               return -ENOMEM;
+
+       ret = mmc_register_bus();
+       if (ret)
+               goto destroy_workqueue;
+
+       ret = mmc_register_host_class();
+       if (ret)
+               goto unregister_bus;
+
+       ret = sdio_register_bus();
+       if (ret)
+               goto unregister_host_class;
+
+       return 0;
+
+unregister_host_class:
+       mmc_unregister_host_class();
+unregister_bus:
+       mmc_unregister_bus();
+destroy_workqueue:
+       destroy_workqueue(workqueue);
+
+       return ret;
+}
+
+static void __exit mmc_exit(void)
+{
+       sdio_unregister_bus();
+       mmc_unregister_host_class();
+       mmc_unregister_bus();
+       destroy_workqueue(workqueue);
+}
+
+subsys_initcall(mmc_init);
+module_exit(mmc_exit);
+
+MODULE_LICENSE("GPL");