sd_ops.c

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/*
 *  linux/drivers/mmc/core/sd_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/types.h>
#include <linux/export.h>
#include <linux/scatterlist.h>

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

#include "core.h"
#include "sd_ops.h"

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

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

    cmd.opcode = MMC_APP_CMD;

    if (card) {
        cmd.arg = card->rca << 16;
        cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
    } else {
        cmd.arg = 0;
        cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_BCR;
    }

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

    /* Check that card supported application commands */
    if (!mmc_host_is_spi(host) && !(cmd.resp[0] & R1_APP_CMD))
        return -EOPNOTSUPP;

    return 0;
}
EXPORT_SYMBOL_GPL(mmc_app_cmd);

int mmc_wait_for_app_cmd(struct mmc_host *host, struct mmc_card *card,
    struct mmc_command *cmd, int retries)
{
    struct mmc_request mrq = {NULL};

    int i, err;

    BUG_ON(!cmd);
    BUG_ON(retries < 0);

    err = -EIO;

    /*
     * We have to resend MMC_APP_CMD for each attempt so
     * we cannot use the retries field in mmc_command.
     */
    for (i = 0;i <= retries;i++) {
        err = mmc_app_cmd(host, card);
        if (err) {
            /* no point in retrying; no APP commands allowed */
            if (mmc_host_is_spi(host)) {
                if (cmd->resp[0] & R1_SPI_ILLEGAL_COMMAND)
                    break;
            }
            continue;
        }

        memset(&mrq, 0, sizeof(struct mmc_request));

        memset(cmd->resp, 0, sizeof(cmd->resp));
        cmd->retries = 0;

        mrq.cmd = cmd;
        cmd->data = NULL;

        mmc_wait_for_req(host, &mrq);

        err = cmd->error;
        if (!cmd->error)
            break;

        /* no point in retrying illegal APP commands */
        if (mmc_host_is_spi(host)) {
            if (cmd->resp[0] & R1_SPI_ILLEGAL_COMMAND)
                break;
        }
    }

    return err;
}

EXPORT_SYMBOL(mmc_wait_for_app_cmd);

int mmc_app_set_bus_width(struct mmc_card *card, int width)
{
    int err;
    struct mmc_command cmd = {0};

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

    cmd.opcode = SD_APP_SET_BUS_WIDTH;
    cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;

    switch (width) {
    case MMC_BUS_WIDTH_1:
        cmd.arg = SD_BUS_WIDTH_1;
        break;
    case MMC_BUS_WIDTH_4:
        cmd.arg = SD_BUS_WIDTH_4;
        break;
    default:
        return -EINVAL;
    }

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

    return 0;
}

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

    BUG_ON(!host);

    cmd.opcode = SD_APP_OP_COND;
    if (mmc_host_is_spi(host))
        cmd.arg = ocr & (1 << 30); /* SPI only defines one bit */
    else
        cmd.arg = ocr;
    cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R3 | MMC_CMD_BCR;

    for (i = 100; i; i--) {
        err = mmc_wait_for_app_cmd(host, NULL, &cmd, MMC_CMD_RETRIES);
        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_send_if_cond(struct mmc_host *host, u32 ocr)
{
    struct mmc_command cmd = {0};
    int err;
    static const u8 test_pattern = 0xAA;
    u8 result_pattern;

    /*
     * To support SD 2.0 cards, we must always invoke SD_SEND_IF_COND
     * before SD_APP_OP_COND. This command will harmlessly fail for
     * SD 1.0 cards.
     */
    cmd.opcode = SD_SEND_IF_COND;
    cmd.arg = ((ocr & 0xFF8000) != 0) << 8 | test_pattern;
    cmd.flags = MMC_RSP_SPI_R7 | MMC_RSP_R7 | MMC_CMD_BCR;

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

    if (mmc_host_is_spi(host))
        result_pattern = cmd.resp[1] & 0xFF;
    else
        result_pattern = cmd.resp[0] & 0xFF;

    if (result_pattern != test_pattern)
        return -EIO;

    return 0;
}

int mmc_send_relative_addr(struct mmc_host *host, unsigned int *rca)
{
    int err;
    struct mmc_command cmd = {0};

    BUG_ON(!host);
    BUG_ON(!rca);

    cmd.opcode = SD_SEND_RELATIVE_ADDR;
    cmd.arg = 0;
    cmd.flags = MMC_RSP_R6 | MMC_CMD_BCR;

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

    *rca = cmd.resp[0] >> 16;

    return 0;
}

int mmc_app_send_scr(struct mmc_card *card, u32 *scr)
{
    int err;
    struct mmc_request mrq = {NULL};
    struct mmc_command cmd = {0};
    struct mmc_data data = {0};
    struct scatterlist sg;
    void *data_buf;

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

    /* NOTE: caller guarantees scr is heap-allocated */

    err = mmc_app_cmd(card->host, card);
    if (err)
        return err;

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

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

    cmd.opcode = SD_APP_SEND_SCR;
    cmd.arg = 0;
    cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;

    data.blksz = 8;
    data.blocks = 1;
    data.flags = MMC_DATA_READ;
    data.sg = &sg;
    data.sg_len = 1;

    sg_init_one(&sg, data_buf, 8);

    mmc_set_data_timeout(&data, card);

    mmc_wait_for_req(card->host, &mrq);

    memcpy(scr, data_buf, sizeof(card->raw_scr));
    kfree(data_buf);

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

    scr[0] = be32_to_cpu(scr[0]);
    scr[1] = be32_to_cpu(scr[1]);

    return 0;
}

int mmc_sd_switch(struct mmc_card *card, int mode, int group,
    u8 value, u8 *resp)
{
    struct mmc_request mrq = {NULL};
    struct mmc_command cmd = {0};
    struct mmc_data data = {0};
    struct scatterlist sg;

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

    /* NOTE: caller guarantees resp is heap-allocated */

    mode = !!mode;
    value &= 0xF;

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

    cmd.opcode = SD_SWITCH;
    cmd.arg = mode << 31 | 0x00FFFFFF;
    cmd.arg &= ~(0xF << (group * 4));
    cmd.arg |= value << (group * 4);
    cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;

    data.blksz = 64;
    data.blocks = 1;
    data.flags = MMC_DATA_READ;
    data.sg = &sg;
    data.sg_len = 1;

    sg_init_one(&sg, resp, 64);

    mmc_set_data_timeout(&data, card);

    mmc_wait_for_req(card->host, &mrq);

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

    return 0;
}

int mmc_app_sd_status(struct mmc_card *card, void *ssr)
{
    int err;
    struct mmc_request mrq = {NULL};
    struct mmc_command cmd = {0};
    struct mmc_data data = {0};
    struct scatterlist sg;

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

    /* NOTE: caller guarantees ssr is heap-allocated */

    err = mmc_app_cmd(card->host, card);
    if (err)
        return err;

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

    cmd.opcode = SD_APP_SD_STATUS;
    cmd.arg = 0;
    cmd.flags = MMC_RSP_SPI_R2 | MMC_RSP_R1 | MMC_CMD_ADTC;

    data.blksz = 64;
    data.blocks = 1;
    data.flags = MMC_DATA_READ;
    data.sg = &sg;
    data.sg_len = 1;

    sg_init_one(&sg, ssr, 64);

    mmc_set_data_timeout(&data, card);

    mmc_wait_for_req(card->host, &mrq);

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

    return 0;
}