/*
 *  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);

/**
 *      mmc_wait_for_app_cmd - start an application command and wait for
                               completion
 *      @host: MMC host to start command
 *      @card: Card to send MMC_APP_CMD to
 *      @cmd: MMC command to start
 *      @retries: maximum number of retries
 *
 *      Sends a MMC_APP_CMD, checks the card response, sends the command
 *      in the parameter and waits for it to complete. Return any error
 *      that occurred while the command was executing.  Do not attempt to
 *      parse the response.
 */
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;
}