sdhci.c

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	/* Wait max 10 ms */
	timeout = 10;

	mask = SDHCI_CMD_INHIBIT;
	if ((cmd->data != NULL) || (cmd->flags & MMC_RSP_BUSY))
		mask |= SDHCI_DATA_INHIBIT;

	/* We shouldn't wait for data inihibit for stop commands, even
	   though they might use busy signaling */
	if (host->mrq->data && (cmd == host->mrq->data->stop))
		mask &= ~SDHCI_DATA_INHIBIT;

	while (readl(host->ioaddr + SDHCI_PRESENT_STATE) & mask) {
		if (timeout == 0) {
			printk(KERN_ERR "%s: Controller never released "
				"inhibit bit(s). Please report this to "
				BUGMAIL ".\n", mmc_hostname(host->mmc));
			sdhci_dumpregs(host);
			cmd->error = MMC_ERR_FAILED;
			tasklet_schedule(&host->finish_tasklet);
			return;
		}
		timeout--;
		mdelay(1);
	}

	mod_timer(&host->timer, jiffies + 10 * HZ);

	host->cmd = cmd;

	sdhci_prepare_data(host, cmd->data);

	writel(cmd->arg, host->ioaddr + SDHCI_ARGUMENT);

	sdhci_set_transfer_mode(host, cmd->data);

	if ((cmd->flags & MMC_RSP_136) && (cmd->flags & MMC_RSP_BUSY)) {
		printk(KERN_ERR "%s: Unsupported response type! "
			"Please report this to " BUGMAIL ".\n",
			mmc_hostname(host->mmc));
		cmd->error = MMC_ERR_INVALID;
		tasklet_schedule(&host->finish_tasklet);
		return;
	}

	if (!(cmd->flags & MMC_RSP_PRESENT))
		flags = SDHCI_CMD_RESP_NONE;
	else if (cmd->flags & MMC_RSP_136)
		flags = SDHCI_CMD_RESP_LONG;
	else if (cmd->flags & MMC_RSP_BUSY)
		flags = SDHCI_CMD_RESP_SHORT_BUSY;
	else
		flags = SDHCI_CMD_RESP_SHORT;

	if (cmd->flags & MMC_RSP_CRC)
		flags |= SDHCI_CMD_CRC;
	if (cmd->flags & MMC_RSP_OPCODE)
		flags |= SDHCI_CMD_INDEX;
	if (cmd->data)
		flags |= SDHCI_CMD_DATA;

	writew(SDHCI_MAKE_CMD(cmd->opcode, flags),
		host->ioaddr + SDHCI_COMMAND);
}

static void sdhci_finish_command(struct sdhci_host *host)
{
	int i;

	BUG_ON(host->cmd == NULL);

	if (host->cmd->flags & MMC_RSP_PRESENT) {
		if (host->cmd->flags & MMC_RSP_136) {
			/* CRC is stripped so we need to do some shifting. */
			for (i = 0;i < 4;i++) {
				host->cmd->resp[i] = readl(host->ioaddr +
					SDHCI_RESPONSE + (3-i)*4) << 8;
				if (i != 3)
					host->cmd->resp[i] |=
						readb(host->ioaddr +
						SDHCI_RESPONSE + (3-i)*4-1);
			}
		} else {
			host->cmd->resp[0] = readl(host->ioaddr + SDHCI_RESPONSE);
		}
	}

	host->cmd->error = MMC_ERR_NONE;

	DBG("Ending cmd (%x)\n", host->cmd->opcode);

	if (host->cmd->data)
		host->data = host->cmd->data;
	else
		tasklet_schedule(&host->finish_tasklet);

	host->cmd = NULL;
}

static void sdhci_set_clock(struct sdhci_host *host, unsigned int clock)
{
	int div;
	u8 ctrl;
	u16 clk;
	unsigned long timeout;

	if (clock == host->clock)
		return;

	writew(0, host->ioaddr + SDHCI_CLOCK_CONTROL);

	ctrl = readb(host->ioaddr + SDHCI_HOST_CONTROL);
	if (clock > 25000000)
		ctrl |= SDHCI_CTRL_HISPD;
	else
		ctrl &= ~SDHCI_CTRL_HISPD;
	writeb(ctrl, host->ioaddr + SDHCI_HOST_CONTROL);

	if (clock == 0)
		goto out;

	for (div = 1;div < 256;div *= 2) {
		if ((host->max_clk / div) <= clock)
			break;
	}
	div >>= 1;

	clk = div << SDHCI_DIVIDER_SHIFT;
	clk |= SDHCI_CLOCK_INT_EN;
	writew(clk, host->ioaddr + SDHCI_CLOCK_CONTROL);

	/* Wait max 10 ms */
	timeout = 10;
	while (!((clk = readw(host->ioaddr + SDHCI_CLOCK_CONTROL))
		& SDHCI_CLOCK_INT_STABLE)) {
		if (timeout == 0) {
			printk(KERN_ERR "%s: Internal clock never stabilised. "
				"Please report this to " BUGMAIL ".\n",
				mmc_hostname(host->mmc));
			sdhci_dumpregs(host);
			return;
		}
		timeout--;
		mdelay(1);
	}

	clk |= SDHCI_CLOCK_CARD_EN;
	writew(clk, host->ioaddr + SDHCI_CLOCK_CONTROL);

out:
	host->clock = clock;
}

static void sdhci_set_power(struct sdhci_host *host, unsigned short power)
{
	u8 pwr;

	if (host->power == power)
		return;

	writeb(0, host->ioaddr + SDHCI_POWER_CONTROL);

	if (power == (unsigned short)-1)
		goto out;

	pwr = SDHCI_POWER_ON;

	switch (power) {
	case MMC_VDD_170:
	case MMC_VDD_180:
	case MMC_VDD_190:
		pwr |= SDHCI_POWER_180;
		break;
	case MMC_VDD_290:
	case MMC_VDD_300:
	case MMC_VDD_310:
		pwr |= SDHCI_POWER_300;
		break;
	case MMC_VDD_320:
	case MMC_VDD_330:
	case MMC_VDD_340:
		pwr |= SDHCI_POWER_330;
		break;
	default:
		BUG();
	}

	writeb(pwr, host->ioaddr + SDHCI_POWER_CONTROL);

out:
	host->power = power;
}

/*****************************************************************************\
 *                                                                           *
 * MMC callbacks                                                             *
 *                                                                           *
\*****************************************************************************/

static void sdhci_request(struct mmc_host *mmc, struct mmc_request *mrq)
{
	struct sdhci_host *host;
	unsigned long flags;

	host = mmc_priv(mmc);

	spin_lock_irqsave(&host->lock, flags);

	WARN_ON(host->mrq != NULL);

	sdhci_activate_led(host);

	host->mrq = mrq;

	if (!(readl(host->ioaddr + SDHCI_PRESENT_STATE) & SDHCI_CARD_PRESENT)) {
		host->mrq->cmd->error = MMC_ERR_TIMEOUT;
		tasklet_schedule(&host->finish_tasklet);
	} else
		sdhci_send_command(host, mrq->cmd);

	mmiowb();
	spin_unlock_irqrestore(&host->lock, flags);
}

static void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
{
	struct sdhci_host *host;
	unsigned long flags;
	u8 ctrl;

	host = mmc_priv(mmc);

	spin_lock_irqsave(&host->lock, flags);

	/*
	 * Reset the chip on each power off.
	 * Should clear out any weird states.
	 */
	if (ios->power_mode == MMC_POWER_OFF) {
		writel(0, host->ioaddr + SDHCI_SIGNAL_ENABLE);
		sdhci_init(host);
	}

	sdhci_set_clock(host, ios->clock);

	if (ios->power_mode == MMC_POWER_OFF)
		sdhci_set_power(host, -1);
	else
		sdhci_set_power(host, ios->vdd);

	ctrl = readb(host->ioaddr + SDHCI_HOST_CONTROL);
	if (ios->bus_width == MMC_BUS_WIDTH_4)
		ctrl |= SDHCI_CTRL_4BITBUS;
	else
		ctrl &= ~SDHCI_CTRL_4BITBUS;
	writeb(ctrl, host->ioaddr + SDHCI_HOST_CONTROL);

	mmiowb();
	spin_unlock_irqrestore(&host->lock, flags);
}

static int sdhci_get_ro(struct mmc_host *mmc)
{
	struct sdhci_host *host;
	unsigned long flags;
	int present;

	host = mmc_priv(mmc);

	spin_lock_irqsave(&host->lock, flags);

	present = readl(host->ioaddr + SDHCI_PRESENT_STATE);

	spin_unlock_irqrestore(&host->lock, flags);

	return !(present & SDHCI_WRITE_PROTECT);
}

static const struct mmc_host_ops sdhci_ops = {
	.request	= sdhci_request,
	.set_ios	= sdhci_set_ios,
	.get_ro		= sdhci_get_ro,
};

/*****************************************************************************\
 *                                                                           *
 * Tasklets                                                                  *
 *                                                                           *
\*****************************************************************************/

static void sdhci_tasklet_card(unsigned long param)
{
	struct sdhci_host *host;
	unsigned long flags;

	host = (struct sdhci_host*)param;

	spin_lock_irqsave(&host->lock, flags);

	if (!(readl(host->ioaddr + SDHCI_PRESENT_STATE) & SDHCI_CARD_PRESENT)) {
		if (host->mrq) {
			printk(KERN_ERR "%s: Card removed during transfer!\n",
				mmc_hostname(host->mmc));
			printk(KERN_ERR "%s: Resetting controller.\n",
				mmc_hostname(host->mmc));

			sdhci_reset(host, SDHCI_RESET_CMD);
			sdhci_reset(host, SDHCI_RESET_DATA);

			host->mrq->cmd->error = MMC_ERR_FAILED;
			tasklet_schedule(&host->finish_tasklet);
		}
	}

	spin_unlock_irqrestore(&host->lock, flags);

	mmc_detect_change(host->mmc, msecs_to_jiffies(500));
}

static void sdhci_tasklet_finish(unsigned long param)
{
	struct sdhci_host *host;
	unsigned long flags;
	struct mmc_request *mrq;

	host = (struct sdhci_host*)param;

	spin_lock_irqsave(&host->lock, flags);

	del_timer(&host->timer);

	mrq = host->mrq;

	DBG("Ending request, cmd (%x)\n", mrq->cmd->opcode);

	/*
	 * The controller needs a reset of internal state machines
	 * upon error conditions.
	 */
	if ((mrq->cmd->error != MMC_ERR_NONE) ||
		(mrq->data && ((mrq->data->error != MMC_ERR_NONE) ||
		(mrq->data->stop && (mrq->data->stop->error != MMC_ERR_NONE))))) {

		/* Some controllers need this kick or reset won't work here */
		if (host->chip->quirks & SDHCI_QUIRK_CLOCK_BEFORE_RESET) {
			unsigned int clock;

			/* This is to force an update */
			clock = host->clock;
			host->clock = 0;
			sdhci_set_clock(host, clock);
		}

		/* Spec says we should do both at the same time, but Ricoh
		   controllers do not like that. */
		sdhci_reset(host, SDHCI_RESET_CMD);
		sdhci_reset(host, SDHCI_RESET_DATA);
	}

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

	sdhci_deactivate_led(host);

	mmiowb();
	spin_unlock_irqrestore(&host->lock, flags);

	mmc_request_done(host->mmc, mrq);
}

static void sdhci_timeout_timer(unsigned long data)
{
	struct sdhci_host *host;
	unsigned long flags;

	host = (struct sdhci_host*)data;

	spin_lock_irqsave(&host->lock, flags);

	if (host->mrq) {
		printk(KERN_ERR "%s: Timeout waiting for hardware interrupt. "
			"Please report this to " BUGMAIL ".\n",
			mmc_hostname(host->mmc));
		sdhci_dumpregs(host);

		if (host->data) {
			host->data->error = MMC_ERR_TIMEOUT;
			sdhci_finish_data(host);
		} else {
			if (host->cmd)
				host->cmd->error = MMC_ERR_TIMEOUT;
			else
				host->mrq->cmd->error = MMC_ERR_TIMEOUT;

			tasklet_schedule(&host->finish_tasklet);
		}
	}

	mmiowb();
	spin_unlock_irqrestore(&host->lock, flags);
}

/*****************************************************************************\
 *                                                                           *
 * Interrupt handling                                                        *
 *                                                                           *
\*****************************************************************************/

static void sdhci_cmd_irq(struct sdhci_host *host, u32 intmask)
{
	BUG_ON(intmask == 0);

	if (!host->cmd) {
		printk(KERN_ERR "%s: Got command interrupt even though no "
			"command operation was in progress.\n",
			mmc_hostname(host->mmc));
		printk(KERN_ERR "%s: Please report this to " BUGMAIL ".\n",
			mmc_hostname(host->mmc));
		sdhci_dumpregs(host);
		return;
	}

	if (intmask & SDHCI_INT_RESPONSE)
		sdhci_finish_command(host);
	else {
		if (intmask & SDHCI_INT_TIMEOUT)
			host->cmd->error = MMC_ERR_TIMEOUT;
		else if (intmask & SDHCI_INT_CRC)
			host->cmd->error = MMC_ERR_BADCRC;
		else if (intmask & (SDHCI_INT_END_BIT | SDHCI_INT_INDEX))
			host->cmd->error = MMC_ERR_FAILED;
		else
			host->cmd->error = MMC_ERR_INVALID;

		tasklet_schedule(&host->finish_tasklet);
	}
}

static void sdhci_data_irq(struct sdhci_host *host, u32 intmask)
{
	BUG_ON(intmask == 0);

	if (!host->data) {
		/*
		 * A data end interrupt is sent together with the response
		 * for the stop command.
		 */
		if (intmask & SDHCI_INT_DATA_END)
			return;

		printk(KERN_ERR "%s: Got data interrupt even though no "
			"data operation was in progress.\n",
			mmc_hostname(host->mmc));
		printk(KERN_ERR "%s: Please report this to " BUGMAIL ".\n",
			mmc_hostname(host->mmc));
		sdhci_dumpregs(host);

		return;
	}

	if (intmask & SDHCI_INT_DATA_TIMEOUT)
		host->data->error = MMC_ERR_TIMEOUT;
	else if (intmask & SDHCI_INT_DATA_CRC)
		host->data->error = MMC_ERR_BADCRC;
	else if (intmask & SDHCI_INT_DATA_END_BIT)
		host->data->error = MMC_ERR_FAILED;

	if (host->data->error != MMC_ERR_NONE)
		sdhci_finish_data(host);
	else {
		if (intmask & (SDHCI_INT_DATA_AVAIL | SDHCI_INT_SPACE_AVAIL))
			sdhci_transfer_pio(host);

		if (intmask & SDHCI_INT_DATA_END)
			sdhci_finish_data(host);
	}
}

static irqreturn_t sdhci_irq(int irq, void *dev_id)
{
	irqreturn_t result;
	struct sdhci_host* host = dev_id;
	u32 intmask;

	spin_lock(&host->lock);

	intmask = readl(host->ioaddr + SDHCI_INT_STATUS);

	if (!intmask) {
		result = IRQ_NONE;
		goto out;
	}

	DBG("*** %s got interrupt: 0x%08x\n", host->slot_descr, intmask);

	if (intmask & (SDHCI_INT_CARD_INSERT | SDHCI_INT_CARD_REMOVE)) {
		writel(intmask & (SDHCI_INT_CARD_INSERT | SDHCI_INT_CARD_REMOVE),
			host->ioaddr + SDHCI_INT_STATUS);
		tasklet_schedule(&host->card_tasklet);
	}

	intmask &= ~(SDHCI_INT_CARD_INSERT | SDHCI_INT_CARD_REMOVE);

	if (intmask & SDHCI_INT_CMD_MASK) {
		writel(intmask & SDHCI_INT_CMD_MASK,
			host->ioaddr + SDHCI_INT_STATUS);
		sdhci_cmd_irq(host, intmask & SDHCI_INT_CMD_MASK);
	}

	if (intmask & SDHCI_INT_DATA_MASK) {
		writel(intmask & SDHCI_INT_DATA_MASK,
			host->ioaddr + SDHCI_INT_STATUS);
		sdhci_data_irq(host, intmask & SDHCI_INT_DATA_MASK);