[openwrt/openwrt.git] / target / linux / s3c24xx / files-2.6.30 / drivers / mfd / glamo / glamo-mci.c

/*
 *  linux/drivers/mmc/host/glamo-mmc.c - Glamo MMC driver
 *
 *  Copyright (C) 2007 Openmoko, Inc,  Andy Green <andy@openmoko.com>
 *  Based on S3C MMC driver that was:
 *  Copyright (C) 2004-2006 maintech GmbH, Thomas Kleffel <tk@maintech.de>
 *
 * 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/mmc/mmc.h>
#include <linux/mmc/sd.h>
#include <linux/mmc/host.h>
#include <linux/platform_device.h>
#include <linux/irq.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/workqueue.h>
#include <linux/crc7.h>
#include <linux/scatterlist.h>
#include <linux/io.h>
#include <linux/mfd/glamo.h>

#include "glamo-mci.h"
#include "glamo-core.h"
#include "glamo-regs.h"

#define DRIVER_NAME "glamo-mci"

static void glamo_mci_send_request(struct mmc_host *mmc);
static void glamo_mci_send_command(struct glamo_mci_host *host,
                                  struct mmc_command *cmd);

/*
 * Max SD clock rate
 *
 * held at /(3 + 1) due to concerns of 100R recommended series resistor
 * allows 16MHz @ 4-bit --> 8MBytes/sec raw
 *
 * you can override this on kernel commandline using
 *
 *   glamo_mci.sd_max_clk=10000000
 *
 * for example
 */

static int sd_max_clk = 50000000 / 3;
module_param(sd_max_clk, int, 0644);

/*
 * Slow SD clock rate
 *
 * you can override this on kernel commandline using
 *
 *   glamo_mci.sd_slow_ratio=8
 *
 * for example
 *
 * platform callback is used to decide effective clock rate, if not
 * defined then max is used, if defined and returns nonzero, rate is
 * divided by this factor
 */

static int sd_slow_ratio = 8;
module_param(sd_slow_ratio, int, 0644);

/*
 * Post-power SD clock rate
 *
 * you can override this on kernel commandline using
 *
 *   glamo_mci.sd_post_power_clock=1000000
 *
 * for example
 *
 * After changing power to card, clock is held at this rate until first bulk
 * transfer completes
 */

static int sd_post_power_clock = 1000000;
module_param(sd_post_power_clock, int, 0644);


/*
 * SD Signal drive strength
 *
 * you can override this on kernel commandline using
 *
 *   glamo_mci.sd_drive=0
 *
 * for example
 */

static int sd_drive;
module_param(sd_drive, int, 0644);

/*
 * SD allow SD clock to run while idle
 *
 * you can override this on kernel commandline using
 *
 *   glamo_mci.sd_idleclk=0
 *
 * for example
 */

static int sd_idleclk = 0; /* disallow idle clock by default */
module_param(sd_idleclk, int, 0644);

/* used to stash real idleclk state in suspend: we force it to run in there */
static int suspend_sd_idleclk;

static inline void glamo_reg_write(struct glamo_mci_host *glamo,
                                u_int16_t reg, u_int16_t val)
{
        writew(val, glamo->mmio_base + reg);
}

static inline u_int16_t glamo_reg_read(struct glamo_mci_host *glamo,
                                   u_int16_t reg)
{
        return readw(glamo->mmio_base + reg);
}

static void glamo_reg_set_bit_mask(struct glamo_mci_host *glamo,
                                u_int16_t reg, u_int16_t mask,
                                u_int16_t val)
{
        u_int16_t tmp;

        val &= mask;

        tmp = glamo_reg_read(glamo, reg);
        tmp &= ~mask;
        tmp |= val;
        glamo_reg_write(glamo, reg, tmp);
}

static void do_pio_read(struct glamo_mci_host *host)
{
        struct scatterlist *sg;
        u16 __iomem *from_ptr = host->data_base;
        struct mmc_data *data = host->mrq->data;
        void *sg_pointer;

        dev_dbg(&host->pdev->dev, "pio_read():\n");
        for (sg = data->sg; sg; sg = sg_next(sg)) {
                sg_pointer = page_address(sg_page(sg)) + sg->offset;


                memcpy(sg_pointer, from_ptr, sg->length);
                from_ptr += sg->length >> 1;

                data->bytes_xfered += sg->length;
        }

        dev_dbg(&host->pdev->dev, "pio_read(): "
                "complete (no more data).\n");
}

static void do_pio_write(struct glamo_mci_host *host)
{
        struct scatterlist *sg;
        u16 __iomem *to_ptr = host->data_base;
        struct mmc_data *data = host->mrq->data;
        void *sg_pointer;

        dev_dbg(&host->pdev->dev, "pio_write():\n");
        for (sg = data->sg; sg; sg = sg_next(sg)) {
                sg_pointer = page_address(sg_page(sg)) + sg->offset;

                data->bytes_xfered += sg->length;

                memcpy(to_ptr, sg_pointer, sg->length);
                to_ptr += sg->length >> 1;
        }

        dev_dbg(&host->pdev->dev, "pio_write(): complete\n");
}

static void glamo_mci_fix_card_div(struct glamo_mci_host *host, int div)
{
        unsigned long flags;

        spin_lock_irqsave(&host->pdata->core->lock, flags);

        if (div < 0) {
                /* stop clock - remove clock from divider input */
                writew(readw(host->pdata->core->base +
                     GLAMO_REG_CLOCK_GEN5_1) & (~GLAMO_CLOCK_GEN51_EN_DIV_TCLK),
                     host->pdata->core->base + GLAMO_REG_CLOCK_GEN5_1);
        } else {

                if (host->force_slow_during_powerup)
                        div = host->clk_rate / sd_post_power_clock;
                else if (host->pdata->glamo_mmc_use_slow &&
                         host->pdata->glamo_mmc_use_slow())
                        div = div * sd_slow_ratio;

                if (div > 255)
                        div = 255;
                /*
                 * set the nearest prescaler factor
                 *
                 * register shared with SCLK divisor -- no chance of race because
                 * we don't use sensor interface
                 */
                writew((readw(host->pdata->core->base +
                              GLAMO_REG_CLOCK_GEN8) & 0xff00) | div,
                       host->pdata->core->base + GLAMO_REG_CLOCK_GEN8);
                /* enable clock to divider input */
                writew(readw(host->pdata->core->base +
                             GLAMO_REG_CLOCK_GEN5_1) | GLAMO_CLOCK_GEN51_EN_DIV_TCLK,
                       host->pdata->core->base + GLAMO_REG_CLOCK_GEN5_1);
        }
        spin_unlock_irqrestore(&host->pdata->core->lock, flags);
        mdelay(5);
}

static int glamo_mci_set_card_clock(struct glamo_mci_host *host, int freq)
{
        int div = 0;
        int real_rate = 0;

        if (freq) {
                /* Set clock */
                for (div = 0; div < 255; div++) {
                        real_rate = host->clk_rate / (div + 1);
                        if (real_rate <= freq)
                                break;
                }

                host->clk_div = div;
                glamo_mci_fix_card_div(host, div);
        } else {
                /* stop clock */
                host->clk_div = 0xff;

                if (!sd_idleclk && !host->force_slow_during_powerup)
                        /* clock off */
                        glamo_mci_fix_card_div(host, -1);
        }
        host->real_rate = real_rate;
        return real_rate;
}


static void glamo_mci_irq_worker(struct work_struct *work)
{
        struct glamo_mci_host *host =
                            container_of(work, struct glamo_mci_host, irq_work);
        struct mmc_command *cmd = host->mrq->cmd;

        if (cmd->data->flags & MMC_DATA_READ) {
                do_pio_read(host);
        }

        /* issue STOP if we have been given one to use */
        if (host->mrq->stop) {
                glamo_mci_send_command(host, host->mrq->stop);
        }

        if (!sd_idleclk && !host->force_slow_during_powerup)
                /* clock off */
                glamo_mci_fix_card_div(host, -1);

        host->mrq = NULL;
        mmc_request_done(host->mmc, cmd->mrq);
}

static irqreturn_t glamo_mci_irq(int irq, void *devid)
{
        struct glamo_mci_host *host = (struct glamo_mci_host*)devid;
        u16 status;
        struct mmc_command *cmd;
        unsigned long flags;

        if (host->suspending) { /* bad news, dangerous time */
                dev_err(&host->pdev->dev, "****glamo_mci_irq before resumed\n");
                goto leave;
        }

        if (!host->mrq)
                goto leave;
        cmd = host->mrq->cmd;
        if (!cmd)
                goto leave;

        spin_lock_irqsave(&host->lock, flags);

        status = readw(host->mmio_base + GLAMO_REG_MMC_RB_STAT1);
        dev_dbg(&host->pdev->dev, "status = 0x%04x\n", status);

        /* we ignore a data timeout report if we are also told the data came */
        if (status & GLAMO_STAT1_MMC_RB_DRDY)
                status &= ~GLAMO_STAT1_MMC_DTOUT;

        if (status & (GLAMO_STAT1_MMC_RTOUT |
                      GLAMO_STAT1_MMC_DTOUT))
                cmd->error = -ETIMEDOUT;
        if (status & (GLAMO_STAT1_MMC_BWERR |
                      GLAMO_STAT1_MMC_BRERR))
                cmd->error = -EILSEQ;
        if (cmd->error) {
                dev_info(&host->pdev->dev, "Error after cmd: 0x%x\n", status);
                goto done;
        }

        /*
         * disable the initial slow start after first bulk transfer
         */
        if (host->force_slow_during_powerup)
                host->force_slow_during_powerup--;

        /*
         * we perform the memcpy out of Glamo memory outside of IRQ context
         * so we don't block other interrupts
         */
        schedule_work(&host->irq_work);

        goto unlock;

done:
        host->mrq = NULL;
        mmc_request_done(host->mmc, cmd->mrq);
unlock:
        spin_unlock_irqrestore(&host->lock, flags);
leave:
        return IRQ_HANDLED;
}

static void glamo_mci_send_command(struct glamo_mci_host *host,
                                  struct mmc_command *cmd)
{
        u8 u8a[6];
        u16 fire = 0;
        unsigned int timeout = 1000000;
        u16 * reg_resp = (u16 *)(host->mmio_base + GLAMO_REG_MMC_CMD_RSP1);
        u16 status;

        /* if we can't do it, reject as busy */
        if (!readw(host->mmio_base + GLAMO_REG_MMC_RB_STAT1) &
             GLAMO_STAT1_MMC_IDLE) {
                host->mrq = NULL;
                cmd->error = -EBUSY;
                mmc_request_done(host->mmc, host->mrq);
                return;
        }

        /* create an array in wire order for CRC computation */
        u8a[0] = 0x40 | (cmd->opcode & 0x3f);
        u8a[1] = (u8)(cmd->arg >> 24);
        u8a[2] = (u8)(cmd->arg >> 16);
        u8a[3] = (u8)(cmd->arg >> 8);
        u8a[4] = (u8)cmd->arg;
        u8a[5] = (crc7(0, u8a, 5) << 1) | 0x01; /* crc7 on first 5 bytes of packet */

        /* issue the wire-order array including CRC in register order */
        writew((u8a[4] << 8) | u8a[5], host->mmio_base + GLAMO_REG_MMC_CMD_REG1);
        writew((u8a[2] << 8) | u8a[3], host->mmio_base + GLAMO_REG_MMC_CMD_REG2);
        writew((u8a[0] << 8) | u8a[1], host->mmio_base + GLAMO_REG_MMC_CMD_REG3);

        /* command index toggle */
        fire |= (host->request_counter & 1) << 12;

        /* set type of command */
        switch (mmc_cmd_type(cmd)) {
        case MMC_CMD_BC:
                fire |= GLAMO_FIRE_MMC_CMDT_BNR;
                break;
        case MMC_CMD_BCR:
                fire |= GLAMO_FIRE_MMC_CMDT_BR;
                break;
        case MMC_CMD_AC:
                fire |= GLAMO_FIRE_MMC_CMDT_AND;
                break;
        case MMC_CMD_ADTC:
                fire |= GLAMO_FIRE_MMC_CMDT_AD;
                break;
        }
        /*
         * if it expects a response, set the type expected
         *
         * R1, Length  : 48bit, Normal response
         * R1b, Length : 48bit, same R1, but added card busy status
         * R2, Length  : 136bit (really 128 bits with CRC snipped)
         * R3, Length  : 48bit (OCR register value)
         * R4, Length  : 48bit, SDIO_OP_CONDITION, Reverse SDIO Card
         * R5, Length  : 48bit, IO_RW_DIRECTION, Reverse SDIO Card
         * R6, Length  : 48bit (RCA register)
         * R7, Length  : 48bit (interface condition, VHS(voltage supplied),
         *                     check pattern, CRC7)
         */
        switch (mmc_resp_type(cmd)) {
        case MMC_RSP_R1: /* same index as R6 and R7 */
                fire |= GLAMO_FIRE_MMC_RSPT_R1;
                break;
        case MMC_RSP_R1B:
                fire |= GLAMO_FIRE_MMC_RSPT_R1b;
                break;
        case MMC_RSP_R2:
                fire |= GLAMO_FIRE_MMC_RSPT_R2;
                break;
        case MMC_RSP_R3:
                fire |= GLAMO_FIRE_MMC_RSPT_R3;
                break;
        /* R4 and R5 supported by chip not defined in linux/mmc/core.h (sdio) */
        }
        /*
         * From the command index, set up the command class in the host ctrllr
         *
         * missing guys present on chip but couldn't figure out how to use yet:
         *     0x0 "stream read"
         *     0x9 "cancel running command"
         */
        switch (cmd->opcode) {
        case MMC_READ_SINGLE_BLOCK:
                fire |= GLAMO_FIRE_MMC_CC_SBR; /* single block read */
                break;
        case MMC_SWITCH: /* 64 byte payload */
        case SD_APP_SEND_SCR:
        case MMC_READ_MULTIPLE_BLOCK:
                /* we will get an interrupt off this */
                if (!cmd->mrq->stop)
                        /* multiblock no stop */
                        fire |= GLAMO_FIRE_MMC_CC_MBRNS;
                else
                         /* multiblock with stop */
                        fire |= GLAMO_FIRE_MMC_CC_MBRS;
                break;
        case MMC_WRITE_BLOCK:
                fire |= GLAMO_FIRE_MMC_CC_SBW; /* single block write */
                break;
        case MMC_WRITE_MULTIPLE_BLOCK:
                if (cmd->mrq->stop)
                         /* multiblock with stop */
                        fire |= GLAMO_FIRE_MMC_CC_MBWS;
                else
                         /* multiblock NO stop-- 'RESERVED'? */
                        fire |= GLAMO_FIRE_MMC_CC_MBWNS;
                break;
        case MMC_STOP_TRANSMISSION:
                fire |= GLAMO_FIRE_MMC_CC_STOP; /* STOP */
                break;
        default:
                fire |= GLAMO_FIRE_MMC_CC_BASIC; /* "basic command" */
                break;
        }
        /* always largest timeout */
        writew(0xfff, host->mmio_base + GLAMO_REG_MMC_TIMEOUT);

        /* Generate interrupt on txfer */
        glamo_reg_set_bit_mask(host, GLAMO_REG_MMC_BASIC, ~0x3e,
                   0x0800 | GLAMO_BASIC_MMC_NO_CLK_RD_WAIT |
                   GLAMO_BASIC_MMC_EN_COMPL_INT | (sd_drive << 6));

        /* send the command out on the wire */
        /* dev_info(&host->pdev->dev, "Using FIRE %04X\n", fire); */
        writew(fire, host->mmio_base + GLAMO_REG_MMC_CMD_FIRE);

        /* we are deselecting card?  because it isn't going to ack then... */
        if ((cmd->opcode == 7) && (cmd->arg == 0))
                return;

        /*
         * we must spin until response is ready or timed out
         * -- we don't get interrupts unless there is a bulk rx
         */
        udelay(5);
        do
                status = readw(host->mmio_base + GLAMO_REG_MMC_RB_STAT1);
        while (((((status >> 15) & 1) != (host->request_counter & 1)) ||
                (!(status & (GLAMO_STAT1_MMC_RB_RRDY |
                             GLAMO_STAT1_MMC_RTOUT |
                             GLAMO_STAT1_MMC_DTOUT |
                             GLAMO_STAT1_MMC_BWERR |
                             GLAMO_STAT1_MMC_BRERR)))) && (timeout--));

        if ((status & (GLAMO_STAT1_MMC_RTOUT |
                                   GLAMO_STAT1_MMC_DTOUT)) ||
                (timeout == 0)) {
                cmd->error = -ETIMEDOUT;
        } else if (status & (GLAMO_STAT1_MMC_BWERR |
                          GLAMO_STAT1_MMC_BRERR)) {
                cmd->error = -EILSEQ;
        }

        if (cmd->flags & MMC_RSP_PRESENT) {
                if (cmd->flags & MMC_RSP_136) {
                        cmd->resp[3] = readw(&reg_resp[0]) |
                                       (readw(&reg_resp[1]) << 16);
                        cmd->resp[2] = readw(&reg_resp[2]) |
                                       (readw(&reg_resp[3]) << 16);
                        cmd->resp[1] = readw(&reg_resp[4]) |
                                       (readw(&reg_resp[5]) << 16);
                        cmd->resp[0] = readw(&reg_resp[6]) |
                                       (readw(&reg_resp[7]) << 16);
                } else {
                        cmd->resp[0] = (readw(&reg_resp[0]) >> 8) |
                                       (readw(&reg_resp[1]) << 8) |
                                       ((readw(&reg_resp[2])) << 24);
                }
        }
}

static int glamo_mci_prepare_pio(struct glamo_mci_host *host,
                                 struct mmc_data *data)
{
        /* set up the block info */
        writew(data->blksz, host->mmio_base + GLAMO_REG_MMC_DATBLKLEN);
        writew(data->blocks, host->mmio_base + GLAMO_REG_MMC_DATBLKCNT);
        dev_dbg(&host->pdev->dev, "(blksz=%d, count=%d)\n",
                                   data->blksz, data->blocks);
        data->bytes_xfered = 0;

        /* if write, prep the write into the shared RAM before the command */
        if (data->flags & MMC_DATA_WRITE) {
                do_pio_write(host);
        }
        return 0;
}

static void glamo_mci_send_request(struct mmc_host *mmc)
{
        struct glamo_mci_host *host = mmc_priv(mmc);
        struct mmc_request *mrq = host->mrq;
        struct mmc_command *cmd = mrq->cmd;
        int timeout = 1000000;

        host->request_counter++;
        /* this guy has data to read/write? */
        if (cmd->data) {
                if(glamo_mci_prepare_pio(host, cmd->data)) {
                        cmd->data->error = -EIO;
                        goto done;
                }
        }

        dev_dbg(&host->pdev->dev,"cmd 0x%x, "
                 "arg 0x%x data=%p mrq->stop=%p flags 0x%x\n",
                 cmd->opcode, cmd->arg, cmd->data, cmd->mrq->stop,
                 cmd->flags);

        /* resume requested clock rate
         * scale it down by sd_slow_ratio if platform requests it
         */
        glamo_mci_fix_card_div(host, host->clk_div);

        glamo_mci_send_command(host, cmd);

        /*
         * if we don't have bulk data to take care of, we're done
         */
        if (!cmd->data || cmd->error)
                goto done;

        /*
         * Otherwise can can use the interrupt as async completion --
         * if there is read data coming, or we wait for write data to complete,
         * exit without mmc_request_done() as the payload interrupt
         * will service it
         */
        dev_dbg(&host->pdev->dev, "Waiting for payload data\n");
        /*
         * if the glamo INT# line isn't wired (*cough* it can happen)
         * I'm afraid we have to spin on the IRQ status bit and "be
         * our own INT# line"
         */
        if (!host->pdata->core->irq_works) {
                /*
                 * we have faith we will get an "interrupt"...
                 * but something insane like suspend problems can mean
                 * we spin here forever, so we timeout after a LONG time
                 */
                while ((!(readw(host->pdata->core->base +
                         GLAMO_REG_IRQ_STATUS) & GLAMO_IRQ_MMC)) &&
                       (timeout--));

                if (timeout < 0) {
                        if (cmd->data->error)
                                cmd->data->error = -ETIMEDOUT;
                        dev_err(&host->pdev->dev, "Payload timeout\n");
                        goto bail;
                }
                /* ack this interrupt source */
                writew(GLAMO_IRQ_MMC, host->pdata->core->base +
                       GLAMO_REG_IRQ_CLEAR);

                /* yay we are an interrupt controller! -- call the ISR
                 * it will stop clock to card
                 */
                glamo_mci_irq(IRQ_GLAMO(GLAMO_IRQIDX_MMC), host);
        }
        return;
done:
        host->mrq = NULL;
        mmc_request_done(host->mmc, cmd->mrq);
bail:
        if (!sd_idleclk && !host->force_slow_during_powerup)
                /* stop the clock to card */
                glamo_mci_fix_card_div(host, -1);
}

static void glamo_mci_request(struct mmc_host *mmc, struct mmc_request *mrq)
{
        struct glamo_mci_host *host = mmc_priv(mmc);

        host->mrq = mrq;
        glamo_mci_send_request(mmc);
}

static void glamo_mci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
{
        struct glamo_mci_host *host = mmc_priv(mmc);
        int bus_width = 0;
        int powering = 0;
        int ret;

        if (host->suspending) {
                dev_err(&host->pdev->dev, "IGNORING glamo_mci_set_ios while "
                                                                 "suspended\n");
                return;
        }

        /* Set power */
        switch(ios->power_mode) {
        case MMC_POWER_UP:
                ret = regulator_enable(host->regulator);
                if (ret)
                        dev_err(&host->pdev->dev, "Failed to enable regulator: %d\n", ret);
                break;
        case MMC_POWER_ON:
                /*
                 * we should use very slow clock until first bulk
                 * transfer completes OK
                 */
                host->force_slow_during_powerup = 1;

                if (host->power_mode_current == MMC_POWER_OFF) {
                        glamo_engine_enable(host->pdata->core,
                                                              GLAMO_ENGINE_MMC);
                        powering = 1;
                }
                break;

        case MMC_POWER_OFF:
        default:
                if (host->power_mode_current == MMC_POWER_OFF)
                        break;
                /* never want clocking with dead card */
                glamo_mci_fix_card_div(host, -1);

                glamo_engine_disable(host->pdata->core,
                                     GLAMO_ENGINE_MMC);

                ret = regulator_disable(host->regulator);
                if (ret)
                        dev_warn(&host->pdev->dev, "Failed to disable regulator: %d\n", ret);
                break;
        }
        host->power_mode_current = ios->power_mode;

        if (host->vdd_current != ios->vdd) {
                ret = mmc_regulator_set_ocr(host->regulator, ios->vdd);
                if (ret)
                        dev_err(&host->pdev->dev, "Failed to set regulator voltage: %d\n", ret);
                else
                        host->vdd_current = ios->vdd;
        }
        glamo_mci_set_card_clock(host, ios->clock);

        /* after power-up, we are meant to give it >= 74 clocks so it can
         * initialize itself.  Doubt any modern cards need it but anyway...
         */
        if (powering)
                mdelay(1);

        if (!sd_idleclk && !host->force_slow_during_powerup)
                /* stop the clock to card, because we are idle until transfer */
                glamo_mci_fix_card_div(host, -1);

        if ((ios->power_mode == MMC_POWER_ON) ||
            (ios->power_mode == MMC_POWER_UP)) {
                dev_info(&host->pdev->dev,
                        "powered (vdd = %d) clk: %lukHz div=%d (req: %ukHz). "
                        "Bus width=%d\n",(int)ios->vdd,
                        host->real_rate / 1000, (int)host->clk_div,
                        ios->clock / 1000, (int)ios->bus_width);
        } else
                dev_info(&host->pdev->dev, "glamo_mci_set_ios: power down.\n");

        /* set bus width */
        if (ios->bus_width == MMC_BUS_WIDTH_4)
                bus_width = GLAMO_BASIC_MMC_EN_4BIT_DATA;
        glamo_reg_set_bit_mask(host, GLAMO_REG_MMC_BASIC,
                                               GLAMO_BASIC_MMC_EN_4BIT_DATA |
                                               GLAMO_BASIC_MMC_EN_DR_STR0 |
                                               GLAMO_BASIC_MMC_EN_DR_STR1,
                                                   bus_width | sd_drive << 6);
}


/*
 * no physical write protect supported by us
 */
static int glamo_mci_get_ro(struct mmc_host *mmc)
{
        return 0;
}

static struct mmc_host_ops glamo_mci_ops = {
        .request        = glamo_mci_request,
        .set_ios        = glamo_mci_set_ios,
        .get_ro         = glamo_mci_get_ro,
};

static int glamo_mci_probe(struct platform_device *pdev)
{
        struct mmc_host         *mmc;
        struct glamo_mci_host   *host;
        int ret;

        dev_info(&pdev->dev, "glamo_mci driver (C)2007 Openmoko, Inc\n");

        mmc = mmc_alloc_host(sizeof(struct glamo_mci_host), &pdev->dev);
        if (!mmc) {
                ret = -ENOMEM;
                goto probe_out;
        }

        host = mmc_priv(mmc);
        host->mmc = mmc;
        host->pdev = pdev;
        host->pdata = pdev->dev.platform_data;
        host->power_mode_current = MMC_POWER_OFF;

        spin_lock_init(&host->lock);
        INIT_WORK(&host->irq_work, glamo_mci_irq_worker);

        host->regulator = regulator_get(pdev->dev.parent, "SD_3V3");
        if (!host->regulator) {
                dev_err(&pdev->dev, "Cannot proceed without regulator.\n");
                ret = -ENODEV;
                goto probe_free_host;
        }

        host->mmio_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        if (!host->mmio_mem) {
                dev_err(&pdev->dev,
                        "failed to get io memory region resouce.\n");
                ret = -ENOENT;
                goto probe_regulator_put;
        }

        host->mmio_mem = request_mem_region(host->mmio_mem->start,
                                            resource_size(host->mmio_mem),
                                            pdev->name);

        if (!host->mmio_mem) {
                dev_err(&pdev->dev, "failed to request io memory region.\n");
                ret = -ENOENT;
                goto probe_regulator_put;
        }

        host->mmio_base = ioremap(host->mmio_mem->start,
                                  resource_size(host->mmio_mem));
        if (!host->mmio_base) {
                dev_err(&pdev->dev, "failed to ioremap() io memory region.\n");
                ret = -EINVAL;
                goto probe_free_mem_region_mmio;
        }


        /* Get ahold of our data buffer we use for data in and out on MMC */
        host->data_mem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
        if (!host->data_mem) {
                dev_err(&pdev->dev,
                        "failed to get io memory region resource.\n");
                ret = -ENOENT;
                goto probe_iounmap_mmio;
        }

        host->data_mem = request_mem_region(host->data_mem->start,
                                            resource_size(host->data_mem),
                                                                                pdev->name);

        if (!host->data_mem) {
                dev_err(&pdev->dev, "failed to request io memory region.\n");
                ret = -ENOENT;
                goto probe_iounmap_mmio;
        }
        host->data_base = ioremap(host->data_mem->start,
                                  resource_size(host->data_mem));

        if (host->data_base == 0) {
                dev_err(&pdev->dev, "failed to ioremap() io memory region.\n");
                ret = -EINVAL;
                goto probe_free_mem_region_data;
        }

        ret = request_irq(IRQ_GLAMO(GLAMO_IRQIDX_MMC), glamo_mci_irq, IRQF_SHARED,
                       pdev->name, host);
        if (ret) {
                dev_err(&pdev->dev, "failed to register irq.\n");
                goto probe_iounmap_data;
        }


        host->vdd_current = 0;
        host->clk_rate = 50000000; /* really it's 49152000 */
        host->clk_div = 16;

        /* explain our host controller capabilities */
        mmc->ops       = &glamo_mci_ops;
        mmc->ocr_avail = mmc_regulator_get_ocrmask(host->regulator);
        mmc->caps      = MMC_CAP_4_BIT_DATA |
                         MMC_CAP_MMC_HIGHSPEED |
                         MMC_CAP_SD_HIGHSPEED;
        mmc->f_min     = host->clk_rate / 256;
        mmc->f_max     = sd_max_clk;

        mmc->max_blk_count = (1 << 16) - 1; /* GLAMO_REG_MMC_RB_BLKCNT */
        mmc->max_blk_size  = (1 << 12) - 1; /* GLAMO_REG_MMC_RB_BLKLEN */
        mmc->max_req_size  = resource_size(host->data_mem);
        mmc->max_seg_size  = mmc->max_req_size;
        mmc->max_phys_segs = 128;
        mmc->max_hw_segs   = 128;

        if (mmc->ocr_avail < 0) {
                dev_warn(&pdev->dev, "Failed to get ocr list for regulator: %d.\n",
                                mmc->ocr_avail);
                mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
        }

        platform_set_drvdata(pdev, mmc);

        glamo_engine_enable(host->pdata->core, GLAMO_ENGINE_MMC);
        glamo_engine_reset(host->pdata->core, GLAMO_ENGINE_MMC);

        if ((ret = mmc_add_host(mmc))) {
                dev_err(&pdev->dev, "failed to add mmc host.\n");
                goto probe_freeirq;
        }

        writew((u16)(host->data_mem->start),
               host->mmio_base + GLAMO_REG_MMC_WDATADS1);
        writew((u16)((host->data_mem->start) >> 16),
               host->mmio_base + GLAMO_REG_MMC_WDATADS2);

        writew((u16)host->data_mem->start, host->mmio_base +
               GLAMO_REG_MMC_RDATADS1);
        writew((u16)(host->data_mem->start >> 16), host->mmio_base +
               GLAMO_REG_MMC_RDATADS2);

        dev_info(&pdev->dev,"initialisation done.\n");
        return 0;

probe_freeirq:
        free_irq(IRQ_GLAMO(GLAMO_IRQIDX_MMC), host);
probe_iounmap_data:
        iounmap(host->data_base);
probe_free_mem_region_data:
        release_mem_region(host->data_mem->start, resource_size(host->data_mem));
probe_iounmap_mmio:
        iounmap(host->mmio_base);
probe_free_mem_region_mmio:
        release_mem_region(host->mmio_mem->start, resource_size(host->mmio_mem));
probe_regulator_put:
        regulator_put(host->regulator);
probe_free_host:
        mmc_free_host(mmc);
probe_out:
        return ret;
}

static int glamo_mci_remove(struct platform_device *pdev)
{
        struct mmc_host *mmc = platform_get_drvdata(pdev);
        struct glamo_mci_host *host = mmc_priv(mmc);

        free_irq(IRQ_GLAMO(GLAMO_IRQIDX_MMC), host);

        mmc_remove_host(mmc);
        iounmap(host->mmio_base);
        iounmap(host->data_base);
        release_mem_region(host->mmio_mem->start, resource_size(host->mmio_mem));
        release_mem_region(host->data_mem->start, resource_size(host->data_mem));

        regulator_put(host->regulator);

        mmc_free_host(mmc);

        glamo_engine_disable(host->pdata->core, GLAMO_ENGINE_MMC);
        return 0;
}


#ifdef CONFIG_PM

static int glamo_mci_suspend(struct platform_device *dev, pm_message_t state)
{
        struct mmc_host *mmc = platform_get_drvdata(dev);
        struct glamo_mci_host   *host = mmc_priv(mmc);
        int ret;

        cancel_work_sync(&host->irq_work);

        /*
         * possible workaround for SD corruption during suspend - resume
         * make sure the clock was running during suspend and consequently
         * resume
         */
        glamo_mci_fix_card_div(host, host->clk_div);

        /* we are going to do more commands to override this in
         * mmc_suspend_host(), so we need to change sd_idleclk for the
         * duration as well
         */
        suspend_sd_idleclk = sd_idleclk;
        sd_idleclk = 1;

        ret = mmc_suspend_host(mmc, state);

        host->suspending++;

        return ret;
}

int glamo_mci_resume(struct platform_device *dev)
{
        struct mmc_host *mmc = platform_get_drvdata(dev);
        struct glamo_mci_host   *host = mmc_priv(mmc);
        int ret;

        sd_idleclk = 1;

        glamo_engine_enable(host->pdata->core, GLAMO_ENGINE_MMC);
        glamo_engine_reset(host->pdata->core, GLAMO_ENGINE_MMC);

        host->suspending--;

        ret = mmc_resume_host(mmc);

        /* put sd_idleclk back to pre-suspend state */
        sd_idleclk = suspend_sd_idleclk;

        return ret;
}
EXPORT_SYMBOL_GPL(glamo_mci_resume);

#else /* CONFIG_PM */
#define glamo_mci_suspend NULL
#define glamo_mci_resume NULL
#endif /* CONFIG_PM */


static struct platform_driver glamo_mci_driver =
{
        .driver.name    = "glamo-mci",
        .probe          = glamo_mci_probe,
        .remove         = glamo_mci_remove,
        .suspend        = glamo_mci_suspend,
        .resume         = glamo_mci_resume,
};

static int __init glamo_mci_init(void)
{
        platform_driver_register(&glamo_mci_driver);
        return 0;
}

static void __exit glamo_mci_exit(void)
{
        platform_driver_unregister(&glamo_mci_driver);
}

module_init(glamo_mci_init);
module_exit(glamo_mci_exit);

MODULE_DESCRIPTION("Glamo MMC/SD Card Interface driver");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Andy Green <andy@openmoko.com>");