root/drivers/mmc/core/sdio_ops.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  linux/drivers/mmc/sdio_ops.c
 *
 *  Copyright 2006-2007 Pierre Ossman
 */

#include <linux/scatterlist.h>

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

#include "core.h"
#include "sdio_ops.h"

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

        cmd.opcode = SD_IO_SEND_OP_COND;
        cmd.arg = ocr;
        cmd.flags = MMC_RSP_SPI_R4 | MMC_RSP_R4 | MMC_CMD_BCR;

        for (i = 100; i; i--) {
                err = mmc_wait_for_cmd(host, &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)) {
                        /*
                         * Both R1_SPI_IDLE and MMC_CARD_BUSY indicate
                         * an initialized card under SPI, but some cards
                         * (Marvell's) only behave when looking at this
                         * one.
                         */
                        if (cmd.resp[1] & MMC_CARD_BUSY)
                                break;
                } else {
                        if (cmd.resp[0] & MMC_CARD_BUSY)
                                break;
                }

                err = -ETIMEDOUT;

                mmc_delay(10);
        }

        if (rocr)
                *rocr = cmd.resp[mmc_host_is_spi(host) ? 1 : 0];

        return err;
}

static int mmc_io_rw_direct_host(struct mmc_host *host, int write, unsigned fn,
        unsigned addr, u8 in, u8 *out)
{
        struct mmc_command cmd = {};
        int err;

        if (fn > 7)
                return -EINVAL;

        /* sanity check */
        if (addr & ~0x1FFFF)
                return -EINVAL;

        cmd.opcode = SD_IO_RW_DIRECT;
        cmd.arg = write ? 0x80000000 : 0x00000000;
        cmd.arg |= fn << 28;
        cmd.arg |= (write && out) ? 0x08000000 : 0x00000000;
        cmd.arg |= addr << 9;
        cmd.arg |= in;
        cmd.flags = MMC_RSP_SPI_R5 | MMC_RSP_R5 | MMC_CMD_AC;

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

        if (mmc_host_is_spi(host)) {
                /* host driver already reported errors */
        } else {
                if (cmd.resp[0] & R5_ERROR)
                        return -EIO;
                if (cmd.resp[0] & R5_FUNCTION_NUMBER)
                        return -EINVAL;
                if (cmd.resp[0] & R5_OUT_OF_RANGE)
                        return -ERANGE;
        }

        if (out) {
                if (mmc_host_is_spi(host))
                        *out = (cmd.resp[0] >> 8) & 0xFF;
                else
                        *out = cmd.resp[0] & 0xFF;
        }

        return 0;
}

int mmc_io_rw_direct(struct mmc_card *card, int write, unsigned fn,
        unsigned addr, u8 in, u8 *out)
{
        return mmc_io_rw_direct_host(card->host, write, fn, addr, in, out);
}

int mmc_io_rw_extended(struct mmc_card *card, int write, unsigned fn,
        unsigned addr, int incr_addr, u8 *buf, unsigned blocks, unsigned blksz)
{
        struct mmc_request mrq = {};
        struct mmc_command cmd = {};
        struct mmc_data data = {};
        struct scatterlist sg, *sg_ptr;
        struct sg_table sgtable;
        unsigned int nents, left_size, i;
        unsigned int seg_size = card->host->max_seg_size;
        int err;

        WARN_ON(blksz == 0);

        /* sanity check */
        if (addr & ~0x1FFFF)
                return -EINVAL;

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

        cmd.opcode = SD_IO_RW_EXTENDED;
        cmd.arg = write ? 0x80000000 : 0x00000000;
        cmd.arg |= fn << 28;
        cmd.arg |= incr_addr ? 0x04000000 : 0x00000000;
        cmd.arg |= addr << 9;
        if (blocks == 0)
                cmd.arg |= (blksz == 512) ? 0 : blksz;  /* byte mode */
        else
                cmd.arg |= 0x08000000 | blocks;         /* block mode */
        cmd.flags = MMC_RSP_SPI_R5 | MMC_RSP_R5 | MMC_CMD_ADTC;

        data.blksz = blksz;
        /* Code in host drivers/fwk assumes that "blocks" always is >=1 */
        data.blocks = blocks ? blocks : 1;
        data.flags = write ? MMC_DATA_WRITE : MMC_DATA_READ;

        left_size = data.blksz * data.blocks;
        nents = DIV_ROUND_UP(left_size, seg_size);
        if (nents > 1) {
                if (sg_alloc_table(&sgtable, nents, GFP_KERNEL))
                        return -ENOMEM;

                data.sg = sgtable.sgl;
                data.sg_len = nents;

                for_each_sg(data.sg, sg_ptr, data.sg_len, i) {
                        sg_set_buf(sg_ptr, buf + i * seg_size,
                                   min(seg_size, left_size));
                        left_size -= seg_size;
                }
        } else {
                data.sg = &sg;
                data.sg_len = 1;

                sg_init_one(&sg, buf, left_size);
        }

        mmc_set_data_timeout(&data, card);

        mmc_pre_req(card->host, &mrq);

        mmc_wait_for_req(card->host, &mrq);

        if (cmd.error)
                err = cmd.error;
        else if (data.error)
                err = data.error;
        else if (mmc_host_is_spi(card->host))
                /* host driver already reported errors */
                err = 0;
        else if (cmd.resp[0] & R5_ERROR)
                err = -EIO;
        else if (cmd.resp[0] & R5_FUNCTION_NUMBER)
                err = -EINVAL;
        else if (cmd.resp[0] & R5_OUT_OF_RANGE)
                err = -ERANGE;
        else
                err = 0;

        mmc_post_req(card->host, &mrq, err);

        if (nents > 1)
                sg_free_table(&sgtable);

        return err;
}

int sdio_reset(struct mmc_host *host)
{
        int ret;
        u8 abort;

        /* SDIO Simplified Specification V2.0, 4.4 Reset for SDIO */

        ret = mmc_io_rw_direct_host(host, 0, 0, SDIO_CCCR_ABORT, 0, &abort);
        if (ret)
                abort = 0x08;
        else
                abort |= 0x08;

        return mmc_io_rw_direct_host(host, 1, 0, SDIO_CCCR_ABORT, abort, NULL);
}