mmc_ops.c

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/*
 *  linux/drivers/mmc/core/mmc_ops.h
 *
 *  Copyright 2006-2007 Pierre Ossman
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or (at
 * your option) any later version.
 */

#include <linux/slab.h>
#include <linux/export.h>
#include <linux/types.h>
#include <linux/scatterlist.h>

#include <linux/mmc/host.h>
#include <linux/mmc/card.h>
#include <linux/mmc/mmc.h>

#include "core.h"
#include "mmc_ops.h"

static int _mmc_select_card(struct mmc_host *host, struct mmc_card *card)
{
    int err;
    struct mmc_command cmd = {0};

    BUG_ON(!host);

    cmd.opcode = MMC_SELECT_CARD;

    if (card) {
        cmd.arg = card->rca << 16;
        cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
    } else {
        cmd.arg = 0;
        cmd.flags = MMC_RSP_NONE | MMC_CMD_AC;
    }

    err = mmc_wait_for_cmd(host, &cmd, MMC_CMD_RETRIES);
    if (err)
        return err;

    return 0;
}

int mmc_select_card(struct mmc_card *card)
{
    BUG_ON(!card);

    return _mmc_select_card(card->host, card);
}

int mmc_deselect_cards(struct mmc_host *host)
{
    return _mmc_select_card(host, NULL);
}

int mmc_card_sleepawake(struct mmc_host *host, int sleep)
{
    struct mmc_command cmd = {0};
    struct mmc_card *card = host->card;
    int err;

    if (sleep)
        mmc_deselect_cards(host);

    cmd.opcode = MMC_SLEEP_AWAKE;
    cmd.arg = card->rca << 16;
    if (sleep)
        cmd.arg |= 1 << 15;

    cmd.flags = MMC_RSP_R1B | MMC_CMD_AC;
    err = mmc_wait_for_cmd(host, &cmd, 0);
    if (err)
        return err;

    /*
     * If the host does not wait while the card signals busy, then we will
     * will have to wait the sleep/awake timeout.  Note, we cannot use the
     * SEND_STATUS command to poll the status because that command (and most
     * others) is invalid while the card sleeps.
     */
    if (!(host->caps & MMC_CAP_WAIT_WHILE_BUSY))
        mmc_delay(DIV_ROUND_UP(card->ext_csd.sa_timeout, 10000));

    if (!sleep)
        err = mmc_select_card(card);

    return err;
}

int mmc_go_idle(struct mmc_host *host)
{
    int err;
    struct mmc_command cmd = {0};

    /*
     * Non-SPI hosts need to prevent chipselect going active during
     * GO_IDLE; that would put chips into SPI mode.  Remind them of
     * that in case of hardware that won't pull up DAT3/nCS otherwise.
     *
     * SPI hosts ignore ios.chip_select; it's managed according to
     * rules that must accommodate non-MMC slaves which this layer
     * won't even know about.
     */
    if (!mmc_host_is_spi(host)) {
        mmc_set_chip_select(host, MMC_CS_HIGH);
        mmc_delay(1);
    }

    cmd.opcode = MMC_GO_IDLE_STATE;
    cmd.arg = 0;
    cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_NONE | MMC_CMD_BC;

    err = mmc_wait_for_cmd(host, &cmd, 0);

    mmc_delay(1);

    if (!mmc_host_is_spi(host)) {
        mmc_set_chip_select(host, MMC_CS_DONTCARE);
        mmc_delay(1);
    }

    host->use_spi_crc = 0;

    return err;
}

int mmc_send_op_cond(struct mmc_host *host, u32 ocr, u32 *rocr)
{
    struct mmc_command cmd = {0};
    int i, err = 0;

    BUG_ON(!host);

    cmd.opcode = MMC_SEND_OP_COND;
    cmd.arg = mmc_host_is_spi(host) ? 0 : ocr;
    cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R3 | MMC_CMD_BCR;

    for (i = 100; i; i--) {
        err = mmc_wait_for_cmd(host, &cmd, 0);
        if (err)
            break;

        /* if we're just probing, do a single pass */
        if (ocr == 0)
            break;

        /* otherwise wait until reset completes */
        if (mmc_host_is_spi(host)) {
            if (!(cmd.resp[0] & R1_SPI_IDLE))
                break;
        } else {
            if (cmd.resp[0] & MMC_CARD_BUSY)
                break;
        }

        err = -ETIMEDOUT;

        mmc_delay(10);
    }

    if (rocr && !mmc_host_is_spi(host))
        *rocr = cmd.resp[0];

    return err;
}

int mmc_all_send_cid(struct mmc_host *host, u32 *cid)
{
    int err;
    struct mmc_command cmd = {0};

    BUG_ON(!host);
    BUG_ON(!cid);

    cmd.opcode = MMC_ALL_SEND_CID;
    cmd.arg = 0;
    cmd.flags = MMC_RSP_R2 | MMC_CMD_BCR;

    err = mmc_wait_for_cmd(host, &cmd, MMC_CMD_RETRIES);
    if (err)
        return err;

    memcpy(cid, cmd.resp, sizeof(u32) * 4);

    return 0;
}

int mmc_set_relative_addr(struct mmc_card *card)
{
    int err;
    struct mmc_command cmd = {0};

    BUG_ON(!card);
    BUG_ON(!card->host);

    cmd.opcode = MMC_SET_RELATIVE_ADDR;
    cmd.arg = card->rca << 16;
    cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;

    err = mmc_wait_for_cmd(card->host, &cmd, MMC_CMD_RETRIES);
    if (err)
        return err;

    return 0;
}

static int
mmc_send_cxd_native(struct mmc_host *host, u32 arg, u32 *cxd, int opcode)
{
    int err;
    struct mmc_command cmd = {0};

    BUG_ON(!host);
    BUG_ON(!cxd);

    cmd.opcode = opcode;
    cmd.arg = arg;
    cmd.flags = MMC_RSP_R2 | MMC_CMD_AC;

    err = mmc_wait_for_cmd(host, &cmd, MMC_CMD_RETRIES);
    if (err)
        return err;

    memcpy(cxd, cmd.resp, sizeof(u32) * 4);

    return 0;
}

/*
 * NOTE: void *buf, caller for the buf is required to use DMA-capable
 * buffer or on-stack buffer (with some overhead in callee).
 */
static int
mmc_send_cxd_data(struct mmc_card *card, struct mmc_host *host,
        u32 opcode, void *buf, unsigned len)
{
    struct mmc_request mrq = {NULL};
    struct mmc_command cmd = {0};
    struct mmc_data data = {0};
    struct scatterlist sg;
    void *data_buf;
    int is_on_stack;

    is_on_stack = object_is_on_stack(buf);
    if (is_on_stack) {
        /*
         * dma onto stack is unsafe/nonportable, but callers to this
         * routine normally provide temporary on-stack buffers ...
         */
        data_buf = kmalloc(len, GFP_KERNEL);
        if (!data_buf)
            return -ENOMEM;
    } else
        data_buf = buf;

    mrq.cmd = &cmd;
    mrq.data = &data;

    cmd.opcode = opcode;
    cmd.arg = 0;

    /* NOTE HACK:  the MMC_RSP_SPI_R1 is always correct here, but we
     * rely on callers to never use this with "native" calls for reading
     * CSD or CID.  Native versions of those commands use the R2 type,
     * not R1 plus a data block.
     */
    cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;

    data.blksz = len;
    data.blocks = 1;
    data.flags = MMC_DATA_READ;
    data.sg = &sg;
    data.sg_len = 1;

    sg_init_one(&sg, data_buf, len);

    if (opcode == MMC_SEND_CSD || opcode == MMC_SEND_CID) {
        /*
         * The spec states that CSR and CID accesses have a timeout
         * of 64 clock cycles.
         */
        data.timeout_ns = 0;
        data.timeout_clks = 64;
    } else
        mmc_set_data_timeout(&data, card);

    mmc_wait_for_req(host, &mrq);

    if (is_on_stack) {
        memcpy(buf, data_buf, len);
        kfree(data_buf);
    }

    if (cmd.error)
        return cmd.error;
    if (data.error)
        return data.error;

    return 0;
}

int mmc_send_csd(struct mmc_card *card, u32 *csd)
{
    int ret, i;
    u32 *csd_tmp;

    if (!mmc_host_is_spi(card->host))
        return mmc_send_cxd_native(card->host, card->rca << 16,
                csd, MMC_SEND_CSD);

    csd_tmp = kmalloc(16, GFP_KERNEL);
    if (!csd_tmp)
        return -ENOMEM;

    ret = mmc_send_cxd_data(card, card->host, MMC_SEND_CSD, csd_tmp, 16);
    if (ret)
        goto err;

    for (i = 0;i < 4;i++)
        csd[i] = be32_to_cpu(csd_tmp[i]);

err:
    kfree(csd_tmp);
    return ret;
}

int mmc_send_cid(struct mmc_host *host, u32 *cid)
{
    int ret, i;
    u32 *cid_tmp;

    if (!mmc_host_is_spi(host)) {
        if (!host->card)
            return -EINVAL;
        return mmc_send_cxd_native(host, host->card->rca << 16,
                cid, MMC_SEND_CID);
    }

    cid_tmp = kmalloc(16, GFP_KERNEL);
    if (!cid_tmp)
        return -ENOMEM;

    ret = mmc_send_cxd_data(NULL, host, MMC_SEND_CID, cid_tmp, 16);
    if (ret)
        goto err;

    for (i = 0;i < 4;i++)
        cid[i] = be32_to_cpu(cid_tmp[i]);

err:
    kfree(cid_tmp);
    return ret;
}

int mmc_send_ext_csd(struct mmc_card *card, u8 *ext_csd)
{
    return mmc_send_cxd_data(card, card->host, MMC_SEND_EXT_CSD,
            ext_csd, 512);
}

int mmc_spi_read_ocr(struct mmc_host *host, int highcap, u32 *ocrp)
{
    struct mmc_command cmd = {0};
    int err;

    cmd.opcode = MMC_SPI_READ_OCR;
    cmd.arg = highcap ? (1 << 30) : 0;
    cmd.flags = MMC_RSP_SPI_R3;

    err = mmc_wait_for_cmd(host, &cmd, 0);

    *ocrp = cmd.resp[1];
    return err;
}

int mmc_spi_set_crc(struct mmc_host *host, int use_crc)
{
    struct mmc_command cmd = {0};
    int err;

    cmd.opcode = MMC_SPI_CRC_ON_OFF;
    cmd.flags = MMC_RSP_SPI_R1;
    cmd.arg = use_crc;

    err = mmc_wait_for_cmd(host, &cmd, 0);
    if (!err)
        host->use_spi_crc = use_crc;
    return err;
}

int __mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value,
           unsigned int timeout_ms, bool use_busy_signal)
{
    int err;
    struct mmc_command cmd = {0};
    u32 status;

    BUG_ON(!card);
    BUG_ON(!card->host);

    cmd.opcode = MMC_SWITCH;
    cmd.arg = (MMC_SWITCH_MODE_WRITE_BYTE << 24) |
          (index << 16) |
          (value << 8) |
          set;
    cmd.flags = MMC_CMD_AC;
    if (use_busy_signal)
        cmd.flags |= MMC_RSP_SPI_R1B | MMC_RSP_R1B;
    else
        cmd.flags |= MMC_RSP_SPI_R1 | MMC_RSP_R1;


    cmd.cmd_timeout_ms = timeout_ms;

    err = mmc_wait_for_cmd(card->host, &cmd, MMC_CMD_RETRIES);
    if (err)
        return err;

    /* No need to check card status in case of unblocking command */
    if (!use_busy_signal)
        return 0;

    /* Must check status to be sure of no errors */
    do {
        err = mmc_send_status(card, &status);
        if (err)
            return err;
        if (card->host->caps & MMC_CAP_WAIT_WHILE_BUSY)
            break;
        if (mmc_host_is_spi(card->host))
            break;
    } while (R1_CURRENT_STATE(status) == R1_STATE_PRG);

    if (mmc_host_is_spi(card->host)) {
        if (status & R1_SPI_ILLEGAL_COMMAND)
            return -EBADMSG;
    } else {
        if (status & 0xFDFFA000)
            pr_warning("%s: unexpected status %#x after "
                   "switch", mmc_hostname(card->host), status);
        if (status & R1_SWITCH_ERROR)
            return -EBADMSG;
    }

    return 0;
}
EXPORT_SYMBOL_GPL(__mmc_switch);

int mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value,
        unsigned int timeout_ms)
{
    return __mmc_switch(card, set, index, value, timeout_ms, true);
}
EXPORT_SYMBOL_GPL(mmc_switch);

int mmc_send_status(struct mmc_card *card, u32 *status)
{
    int err;
    struct mmc_command cmd = {0};

    BUG_ON(!card);
    BUG_ON(!card->host);

    cmd.opcode = MMC_SEND_STATUS;
    if (!mmc_host_is_spi(card->host))
        cmd.arg = card->rca << 16;
    cmd.flags = MMC_RSP_SPI_R2 | MMC_RSP_R1 | MMC_CMD_AC;

    err = mmc_wait_for_cmd(card->host, &cmd, MMC_CMD_RETRIES);
    if (err)
        return err;

    /* NOTE: callers are required to understand the difference
     * between "native" and SPI format status words!
     */
    if (status)
        *status = cmd.resp[0];

    return 0;
}

static int
mmc_send_bus_test(struct mmc_card *card, struct mmc_host *host, u8 opcode,
          u8 len)
{
    struct mmc_request mrq = {NULL};
    struct mmc_command cmd = {0};
    struct mmc_data data = {0};
    struct scatterlist sg;
    u8 *data_buf;
    u8 *test_buf;
    int i, err;
    static u8 testdata_8bit[8] = { 0x55, 0xaa, 0, 0, 0, 0, 0, 0 };
    static u8 testdata_4bit[4] = { 0x5a, 0, 0, 0 };

    /* dma onto stack is unsafe/nonportable, but callers to this
     * routine normally provide temporary on-stack buffers ...
     */
    data_buf = kmalloc(len, GFP_KERNEL);
    if (!data_buf)
        return -ENOMEM;

    if (len == 8)
        test_buf = testdata_8bit;
    else if (len == 4)
        test_buf = testdata_4bit;
    else {
        pr_err("%s: Invalid bus_width %d\n",
               mmc_hostname(host), len);
        kfree(data_buf);
        return -EINVAL;
    }

    if (opcode == MMC_BUS_TEST_W)
        memcpy(data_buf, test_buf, len);

    mrq.cmd = &cmd;
    mrq.data = &data;
    cmd.opcode = opcode;
    cmd.arg = 0;

    /* NOTE HACK:  the MMC_RSP_SPI_R1 is always correct here, but we
     * rely on callers to never use this with "native" calls for reading
     * CSD or CID.  Native versions of those commands use the R2 type,
     * not R1 plus a data block.
     */
    cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;

    data.blksz = len;
    data.blocks = 1;
    if (opcode == MMC_BUS_TEST_R)
        data.flags = MMC_DATA_READ;
    else
        data.flags = MMC_DATA_WRITE;

    data.sg = &sg;
    data.sg_len = 1;
    sg_init_one(&sg, data_buf, len);
    mmc_wait_for_req(host, &mrq);
    err = 0;
    if (opcode == MMC_BUS_TEST_R) {
        for (i = 0; i < len / 4; i++)
            if ((test_buf[i] ^ data_buf[i]) != 0xff) {
                err = -EIO;
                break;
            }
    }
    kfree(data_buf);

    if (cmd.error)
        return cmd.error;
    if (data.error)
        return data.error;

    return err;
}

int mmc_bus_test(struct mmc_card *card, u8 bus_width)
{
    int err, width;

    if (bus_width == MMC_BUS_WIDTH_8)
        width = 8;
    else if (bus_width == MMC_BUS_WIDTH_4)
        width = 4;
    else if (bus_width == MMC_BUS_WIDTH_1)
        return 0; /* no need for test */
    else
        return -EINVAL;

    /*
     * Ignore errors from BUS_TEST_W.  BUS_TEST_R will fail if there
     * is a problem.  This improves chances that the test will work.
     */
    mmc_send_bus_test(card, card->host, MMC_BUS_TEST_W, width);
    err = mmc_send_bus_test(card, card->host, MMC_BUS_TEST_R, width);
    return err;
}

int mmc_send_hpi_cmd(struct mmc_card *card, u32 *status)
{
    struct mmc_command cmd = {0};
    unsigned int opcode;
    int err;

    if (!card->ext_csd.hpi) {
        pr_warning("%s: Card didn't support HPI command\n",
               mmc_hostname(card->host));
        return -EINVAL;
    }

    opcode = card->ext_csd.hpi_cmd;
    if (opcode == MMC_STOP_TRANSMISSION)
        cmd.flags = MMC_RSP_R1B | MMC_CMD_AC;
    else if (opcode == MMC_SEND_STATUS)
        cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;

    cmd.opcode = opcode;
    cmd.arg = card->rca << 16 | 1;

    err = mmc_wait_for_cmd(card->host, &cmd, 0);
    if (err) {
        pr_warn("%s: error %d interrupting operation. "
            "HPI command response %#x\n", mmc_hostname(card->host),
            err, cmd.resp[0]);
        return err;
    }
    if (status)
        *status = cmd.resp[0];

    return 0;
}