mmc: tmio: split core functionality, DMA and MFD glue

TMIO MMC chips contain an SD / SDIO IP core from Panasonic, similar to
the one, used in MN5774 and other MN57xx controllers. These IP cores are
included in many multifunction devices, in sh-mobile chips from Renesas,
in the latter case they can also use DMA. Some sh-mobile implementations
also have some other specialities, that MFD-based solutions don't have.
This makes supporting all these features in a monolithic driver inconveniet
and error-prone. This patch splits the driver into 3 parts: the core,
the MFD glue and the DMA support. In case of a modular build, two modules
will be built: mmc_tmio_core and mmc_tmio.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Chris Ball <cjb@laptop.org>

1 files changed, 923 insertions, 0 deletions

diff --git a/drivers/mmc/host/tmio_mmc_pio.c b/drivers/mmc/host/tmio_mmc_pio.c
new file mode 100644
index 000000000000..a7406e3701c9
--- /dev/null
+++ b/drivers/mmc/host/tmio_mmc_pio.c
@@ -0,0 +1,923 @@
+/*
+ * linux/drivers/mmc/host/tmio_mmc_pio.c
+ *
+ * Copyright (C) 2011 Guennadi Liakhovetski
+ * Copyright (C) 2007 Ian Molton
+ * Copyright (C) 2004 Ian Molton
+ *
+ * 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.
+ *
+ * Driver for the MMC / SD / SDIO IP found in:
+ *
+ * TC6393XB, TC6391XB, TC6387XB, T7L66XB, ASIC3, SH-Mobile SoCs
+ *
+ * This driver draws mainly on scattered spec sheets, Reverse engineering
+ * of the toshiba e800  SD driver and some parts of the 2.4 ASIC3 driver (4 bit
+ * support). (Further 4 bit support from a later datasheet).
+ *
+ * TODO:
+ *   Investigate using a workqueue for PIO transfers
+ *   Eliminate FIXMEs
+ *   SDIO support
+ *   Better Power management
+ *   Handle MMC errors better
+ *   double buffer support
+ *
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/highmem.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/mfd/tmio.h>
+#include <linux/mmc/host.h>
+#include <linux/module.h>
+#include <linux/pagemap.h>
+#include <linux/platform_device.h>
+#include <linux/scatterlist.h>
+#include <linux/workqueue.h>
+#include <linux/spinlock.h>
+
+#include "tmio_mmc.h"
+
+#define CTL_SD_CMD 0x00
+#define CTL_ARG_REG 0x04
+#define CTL_STOP_INTERNAL_ACTION 0x08
+#define CTL_XFER_BLK_COUNT 0xa
+#define CTL_RESPONSE 0x0c
+#define CTL_STATUS 0x1c
+#define CTL_IRQ_MASK 0x20
+#define CTL_SD_CARD_CLK_CTL 0x24
+#define CTL_SD_XFER_LEN 0x26
+#define CTL_SD_MEM_CARD_OPT 0x28
+#define CTL_SD_ERROR_DETAIL_STATUS 0x2c
+#define CTL_SD_DATA_PORT 0x30
+#define CTL_TRANSACTION_CTL 0x34
+#define CTL_SDIO_STATUS 0x36
+#define CTL_SDIO_IRQ_MASK 0x38
+#define CTL_RESET_SD 0xe0
+#define CTL_SDIO_REGS 0x100
+#define CTL_CLK_AND_WAIT_CTL 0x138
+#define CTL_RESET_SDIO 0x1e0
+
+static u16 sd_ctrl_read16(struct tmio_mmc_host *host, int addr)
+{
+	return readw(host->ctl + (addr << host->bus_shift));
+}
+
+static void sd_ctrl_read16_rep(struct tmio_mmc_host *host, int addr,
+		u16 *buf, int count)
+{
+	readsw(host->ctl + (addr << host->bus_shift), buf, count);
+}
+
+static u32 sd_ctrl_read32(struct tmio_mmc_host *host, int addr)
+{
+	return readw(host->ctl + (addr << host->bus_shift)) |
+	       readw(host->ctl + ((addr + 2) << host->bus_shift)) << 16;
+}
+
+static void sd_ctrl_write16(struct tmio_mmc_host *host, int addr, u16 val)
+{
+	writew(val, host->ctl + (addr << host->bus_shift));
+}
+
+static void sd_ctrl_write16_rep(struct tmio_mmc_host *host, int addr,
+		u16 *buf, int count)
+{
+	writesw(host->ctl + (addr << host->bus_shift), buf, count);
+}
+
+static void sd_ctrl_write32(struct tmio_mmc_host *host, int addr, u32 val)
+{
+	writew(val, host->ctl + (addr << host->bus_shift));
+	writew(val >> 16, host->ctl + ((addr + 2) << host->bus_shift));
+}
+
+void tmio_mmc_enable_mmc_irqs(struct tmio_mmc_host *host, u32 i)
+{
+	u32 mask = sd_ctrl_read32(host, CTL_IRQ_MASK) & ~(i & TMIO_MASK_IRQ);
+	sd_ctrl_write32(host, CTL_IRQ_MASK, mask);
+}
+
+void tmio_mmc_disable_mmc_irqs(struct tmio_mmc_host *host, u32 i)
+{
+	u32 mask = sd_ctrl_read32(host, CTL_IRQ_MASK) | (i & TMIO_MASK_IRQ);
+	sd_ctrl_write32(host, CTL_IRQ_MASK, mask);
+}
+
+static void tmio_mmc_ack_mmc_irqs(struct tmio_mmc_host *host, u32 i)
+{
+	sd_ctrl_write32(host, CTL_STATUS, ~i);
+}
+
+static void tmio_mmc_init_sg(struct tmio_mmc_host *host, struct mmc_data *data)
+{
+	host->sg_len = data->sg_len;
+	host->sg_ptr = data->sg;
+	host->sg_orig = data->sg;
+	host->sg_off = 0;
+}
+
+static int tmio_mmc_next_sg(struct tmio_mmc_host *host)
+{
+	host->sg_ptr = sg_next(host->sg_ptr);
+	host->sg_off = 0;
+	return --host->sg_len;
+}
+
+#ifdef CONFIG_MMC_DEBUG
+
+#define STATUS_TO_TEXT(a, status, i) \
+	do { \
+		if (status & TMIO_STAT_##a) { \
+			if (i++) \
+				printk(" | "); \
+			printk(#a); \
+		} \
+	} while (0)
+
+static void pr_debug_status(u32 status)
+{
+	int i = 0;
+	printk(KERN_DEBUG "status: %08x = ", status);
+	STATUS_TO_TEXT(CARD_REMOVE, status, i);
+	STATUS_TO_TEXT(CARD_INSERT, status, i);
+	STATUS_TO_TEXT(SIGSTATE, status, i);
+	STATUS_TO_TEXT(WRPROTECT, status, i);
+	STATUS_TO_TEXT(CARD_REMOVE_A, status, i);
+	STATUS_TO_TEXT(CARD_INSERT_A, status, i);
+	STATUS_TO_TEXT(SIGSTATE_A, status, i);
+	STATUS_TO_TEXT(CMD_IDX_ERR, status, i);
+	STATUS_TO_TEXT(STOPBIT_ERR, status, i);
+	STATUS_TO_TEXT(ILL_FUNC, status, i);
+	STATUS_TO_TEXT(CMD_BUSY, status, i);
+	STATUS_TO_TEXT(CMDRESPEND, status, i);
+	STATUS_TO_TEXT(DATAEND, status, i);
+	STATUS_TO_TEXT(CRCFAIL, status, i);
+	STATUS_TO_TEXT(DATATIMEOUT, status, i);
+	STATUS_TO_TEXT(CMDTIMEOUT, status, i);
+	STATUS_TO_TEXT(RXOVERFLOW, status, i);
+	STATUS_TO_TEXT(TXUNDERRUN, status, i);
+	STATUS_TO_TEXT(RXRDY, status, i);
+	STATUS_TO_TEXT(TXRQ, status, i);
+	STATUS_TO_TEXT(ILL_ACCESS, status, i);
+	printk("\n");
+}
+
+#else
+#define pr_debug_status(s)  do { } while (0)
+#endif
+
+static void tmio_mmc_enable_sdio_irq(struct mmc_host *mmc, int enable)
+{
+	struct tmio_mmc_host *host = mmc_priv(mmc);
+
+	if (enable) {
+		host->sdio_irq_enabled = 1;
+		sd_ctrl_write16(host, CTL_TRANSACTION_CTL, 0x0001);
+		sd_ctrl_write16(host, CTL_SDIO_IRQ_MASK,
+			(TMIO_SDIO_MASK_ALL & ~TMIO_SDIO_STAT_IOIRQ));
+	} else {
+		sd_ctrl_write16(host, CTL_SDIO_IRQ_MASK, TMIO_SDIO_MASK_ALL);
+		sd_ctrl_write16(host, CTL_TRANSACTION_CTL, 0x0000);
+		host->sdio_irq_enabled = 0;
+	}
+}
+
+static void tmio_mmc_set_clock(struct tmio_mmc_host *host, int new_clock)
+{
+	u32 clk = 0, clock;
+
+	if (new_clock) {
+		for (clock = host->mmc->f_min, clk = 0x80000080;
+			new_clock >= (clock<<1); clk >>= 1)
+			clock <<= 1;
+		clk |= 0x100;
+	}
+
+	if (host->set_clk_div)
+		host->set_clk_div(host->pdev, (clk>>22) & 1);
+
+	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, clk & 0x1ff);
+}
+
+static void tmio_mmc_clk_stop(struct tmio_mmc_host *host)
+{
+	struct tmio_mmc_data *pdata = host->pdata;
+
+	/*
+	 * Testing on sh-mobile showed that SDIO IRQs are unmasked when
+	 * CTL_CLK_AND_WAIT_CTL gets written, so we have to disable the
+	 * device IRQ here and restore the SDIO IRQ mask before
+	 * re-enabling the device IRQ.
+	 */
+	if (pdata->flags & TMIO_MMC_SDIO_IRQ)
+		disable_irq(host->irq);
+	sd_ctrl_write16(host, CTL_CLK_AND_WAIT_CTL, 0x0000);
+	msleep(10);
+	if (pdata->flags & TMIO_MMC_SDIO_IRQ) {
+		tmio_mmc_enable_sdio_irq(host->mmc, host->sdio_irq_enabled);
+		enable_irq(host->irq);
+	}
+	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~0x0100 &
+		sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
+	msleep(10);
+}
+
+static void tmio_mmc_clk_start(struct tmio_mmc_host *host)
+{
+	struct tmio_mmc_data *pdata = host->pdata;
+
+	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, 0x0100 |
+		sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
+	msleep(10);
+	/* see comment in tmio_mmc_clk_stop above */
+	if (pdata->flags & TMIO_MMC_SDIO_IRQ)
+		disable_irq(host->irq);
+	sd_ctrl_write16(host, CTL_CLK_AND_WAIT_CTL, 0x0100);
+	msleep(10);
+	if (pdata->flags & TMIO_MMC_SDIO_IRQ) {
+		tmio_mmc_enable_sdio_irq(host->mmc, host->sdio_irq_enabled);
+		enable_irq(host->irq);
+	}
+}
+
+static void tmio_mmc_reset(struct tmio_mmc_host *host)
+{
+	/* FIXME - should we set stop clock reg here */
+	sd_ctrl_write16(host, CTL_RESET_SD, 0x0000);
+	sd_ctrl_write16(host, CTL_RESET_SDIO, 0x0000);
+	msleep(10);
+	sd_ctrl_write16(host, CTL_RESET_SD, 0x0001);
+	sd_ctrl_write16(host, CTL_RESET_SDIO, 0x0001);
+	msleep(10);
+}
+
+static void tmio_mmc_reset_work(struct work_struct *work)
+{
+	struct tmio_mmc_host *host = container_of(work, struct tmio_mmc_host,
+						  delayed_reset_work.work);
+	struct mmc_request *mrq;
+	unsigned long flags;
+
+	spin_lock_irqsave(&host->lock, flags);
+	mrq = host->mrq;
+
+	/* request already finished */
+	if (!mrq
+	    || time_is_after_jiffies(host->last_req_ts +
+		msecs_to_jiffies(2000))) {
+		spin_unlock_irqrestore(&host->lock, flags);
+		return;
+	}
+
+	dev_warn(&host->pdev->dev,
+		"timeout waiting for hardware interrupt (CMD%u)\n",
+		mrq->cmd->opcode);
+
+	if (host->data)
+		host->data->error = -ETIMEDOUT;
+	else if (host->cmd)
+		host->cmd->error = -ETIMEDOUT;
+	else
+		mrq->cmd->error = -ETIMEDOUT;
+
+	host->cmd = NULL;
+	host->data = NULL;
+	host->mrq = NULL;
+	host->force_pio = false;
+
+	spin_unlock_irqrestore(&host->lock, flags);
+
+	tmio_mmc_reset(host);
+
+	mmc_request_done(host->mmc, mrq);
+}
+
+static void tmio_mmc_finish_request(struct tmio_mmc_host *host)
+{
+	struct mmc_request *mrq = host->mrq;
+
+	if (!mrq)
+		return;
+
+	host->mrq = NULL;
+	host->cmd = NULL;
+	host->data = NULL;
+	host->force_pio = false;
+
+	cancel_delayed_work(&host->delayed_reset_work);
+
+	mmc_request_done(host->mmc, mrq);
+}
+
+/* These are the bitmasks the tmio chip requires to implement the MMC response
+ * types. Note that R1 and R6 are the same in this scheme. */
+#define APP_CMD        0x0040
+#define RESP_NONE      0x0300
+#define RESP_R1        0x0400
+#define RESP_R1B       0x0500
+#define RESP_R2        0x0600
+#define RESP_R3        0x0700
+#define DATA_PRESENT   0x0800
+#define TRANSFER_READ  0x1000
+#define TRANSFER_MULTI 0x2000
+#define SECURITY_CMD   0x4000
+
+static int tmio_mmc_start_command(struct tmio_mmc_host *host, struct mmc_command *cmd)
+{
+	struct mmc_data *data = host->data;
+	int c = cmd->opcode;
+
+	/* Command 12 is handled by hardware */
+	if (cmd->opcode == 12 && !cmd->arg) {
+		sd_ctrl_write16(host, CTL_STOP_INTERNAL_ACTION, 0x001);
+		return 0;
+	}
+
+	switch (mmc_resp_type(cmd)) {
+	case MMC_RSP_NONE: c |= RESP_NONE; break;
+	case MMC_RSP_R1:   c |= RESP_R1;   break;
+	case MMC_RSP_R1B:  c |= RESP_R1B;  break;
+	case MMC_RSP_R2:   c |= RESP_R2;   break;
+	case MMC_RSP_R3:   c |= RESP_R3;   break;
+	default:
+		pr_debug("Unknown response type %d\n", mmc_resp_type(cmd));
+		return -EINVAL;
+	}
+
+	host->cmd = cmd;
+
+/* FIXME - this seems to be ok commented out but the spec suggest this bit
+ *         should be set when issuing app commands.
+ *	if(cmd->flags & MMC_FLAG_ACMD)
+ *		c |= APP_CMD;
+ */
+	if (data) {
+		c |= DATA_PRESENT;
+		if (data->blocks > 1) {
+			sd_ctrl_write16(host, CTL_STOP_INTERNAL_ACTION, 0x100);
+			c |= TRANSFER_MULTI;
+		}
+		if (data->flags & MMC_DATA_READ)
+			c |= TRANSFER_READ;
+	}
+
+	tmio_mmc_enable_mmc_irqs(host, TMIO_MASK_CMD);
+
+	/* Fire off the command */
+	sd_ctrl_write32(host, CTL_ARG_REG, cmd->arg);
+	sd_ctrl_write16(host, CTL_SD_CMD, c);
+
+	return 0;
+}
+
+/*
+ * This chip always returns (at least?) as much data as you ask for.
+ * I'm unsure what happens if you ask for less than a block. This should be
+ * looked into to ensure that a funny length read doesnt hose the controller.
+ */
+static void tmio_mmc_pio_irq(struct tmio_mmc_host *host)
+{
+	struct mmc_data *data = host->data;
+	void *sg_virt;
+	unsigned short *buf;
+	unsigned int count;
+	unsigned long flags;
+
+	if ((host->chan_tx || host->chan_rx) && !host->force_pio) {
+		pr_err("PIO IRQ in DMA mode!\n");
+		return;
+	} else if (!data) {
+		pr_debug("Spurious PIO IRQ\n");
+		return;
+	}
+
+	sg_virt = tmio_mmc_kmap_atomic(host->sg_ptr, &flags);
+	buf = (unsigned short *)(sg_virt + host->sg_off);
+
+	count = host->sg_ptr->length - host->sg_off;
+	if (count > data->blksz)
+		count = data->blksz;
+
+	pr_debug("count: %08x offset: %08x flags %08x\n",
+		 count, host->sg_off, data->flags);
+
+	/* Transfer the data */
+	if (data->flags & MMC_DATA_READ)
+		sd_ctrl_read16_rep(host, CTL_SD_DATA_PORT, buf, count >> 1);
+	else
+		sd_ctrl_write16_rep(host, CTL_SD_DATA_PORT, buf, count >> 1);
+
+	host->sg_off += count;
+
+	tmio_mmc_kunmap_atomic(host->sg_ptr, &flags, sg_virt);
+
+	if (host->sg_off == host->sg_ptr->length)
+		tmio_mmc_next_sg(host);
+
+	return;
+}
+
+static void tmio_mmc_check_bounce_buffer(struct tmio_mmc_host *host)
+{
+	if (host->sg_ptr == &host->bounce_sg) {
+		unsigned long flags;
+		void *sg_vaddr = tmio_mmc_kmap_atomic(host->sg_orig, &flags);
+		memcpy(sg_vaddr, host->bounce_buf, host->bounce_sg.length);
+		tmio_mmc_kunmap_atomic(host->sg_orig, &flags, sg_vaddr);
+	}
+}
+
+/* needs to be called with host->lock held */
+void tmio_mmc_do_data_irq(struct tmio_mmc_host *host)
+{
+	struct mmc_data *data = host->data;
+	struct mmc_command *stop;
+
+	host->data = NULL;
+
+	if (!data) {
+		dev_warn(&host->pdev->dev, "Spurious data end IRQ\n");
+		return;
+	}
+	stop = data->stop;
+
+	/* FIXME - return correct transfer count on errors */
+	if (!data->error)
+		data->bytes_xfered = data->blocks * data->blksz;
+	else
+		data->bytes_xfered = 0;
+
+	pr_debug("Completed data request\n");
+
+	/*
+	 * FIXME: other drivers allow an optional stop command of any given type
+	 *        which we dont do, as the chip can auto generate them.
+	 *        Perhaps we can be smarter about when to use auto CMD12 and
+	 *        only issue the auto request when we know this is the desired
+	 *        stop command, allowing fallback to the stop command the
+	 *        upper layers expect. For now, we do what works.
+	 */
+
+	if (data->flags & MMC_DATA_READ) {
+		if (host->chan_rx && !host->force_pio)
+			tmio_mmc_check_bounce_buffer(host);
+		dev_dbg(&host->pdev->dev, "Complete Rx request %p\n",
+			host->mrq);
+	} else {
+		dev_dbg(&host->pdev->dev, "Complete Tx request %p\n",
+			host->mrq);
+	}
+
+	if (stop) {
+		if (stop->opcode == 12 && !stop->arg)
+			sd_ctrl_write16(host, CTL_STOP_INTERNAL_ACTION, 0x000);
+		else
+			BUG();
+	}
+
+	tmio_mmc_finish_request(host);
+}
+
+static void tmio_mmc_data_irq(struct tmio_mmc_host *host)
+{
+	struct mmc_data *data;
+	spin_lock(&host->lock);
+	data = host->data;
+
+	if (!data)
+		goto out;
+
+	if (host->chan_tx && (data->flags & MMC_DATA_WRITE) && !host->force_pio) {
+		/*
+		 * Has all data been written out yet? Testing on SuperH showed,
+		 * that in most cases the first interrupt comes already with the
+		 * BUSY status bit clear, but on some operations, like mount or
+		 * in the beginning of a write / sync / umount, there is one
+		 * DATAEND interrupt with the BUSY bit set, in this cases
+		 * waiting for one more interrupt fixes the problem.
+		 */
+		if (!(sd_ctrl_read32(host, CTL_STATUS) & TMIO_STAT_CMD_BUSY)) {
+			tmio_mmc_disable_mmc_irqs(host, TMIO_STAT_DATAEND);
+			tasklet_schedule(&host->dma_complete);
+		}
+	} else if (host->chan_rx && (data->flags & MMC_DATA_READ) && !host->force_pio) {
+		tmio_mmc_disable_mmc_irqs(host, TMIO_STAT_DATAEND);
+		tasklet_schedule(&host->dma_complete);
+	} else {
+		tmio_mmc_do_data_irq(host);
+		tmio_mmc_disable_mmc_irqs(host, TMIO_MASK_READOP | TMIO_MASK_WRITEOP);
+	}
+out:
+	spin_unlock(&host->lock);
+}
+
+static void tmio_mmc_cmd_irq(struct tmio_mmc_host *host,
+	unsigned int stat)
+{
+	struct mmc_command *cmd = host->cmd;
+	int i, addr;
+
+	spin_lock(&host->lock);
+
+	if (!host->cmd) {
+		pr_debug("Spurious CMD irq\n");
+		goto out;
+	}
+
+	host->cmd = NULL;
+
+	/* This controller is sicker than the PXA one. Not only do we need to
+	 * drop the top 8 bits of the first response word, we also need to
+	 * modify the order of the response for short response command types.
+	 */
+
+	for (i = 3, addr = CTL_RESPONSE ; i >= 0 ; i--, addr += 4)
+		cmd->resp[i] = sd_ctrl_read32(host, addr);
+
+	if (cmd->flags &  MMC_RSP_136) {
+		cmd->resp[0] = (cmd->resp[0] << 8) | (cmd->resp[1] >> 24);
+		cmd->resp[1] = (cmd->resp[1] << 8) | (cmd->resp[2] >> 24);
+		cmd->resp[2] = (cmd->resp[2] << 8) | (cmd->resp[3] >> 24);
+		cmd->resp[3] <<= 8;
+	} else if (cmd->flags & MMC_RSP_R3) {
+		cmd->resp[0] = cmd->resp[3];
+	}
+
+	if (stat & TMIO_STAT_CMDTIMEOUT)
+		cmd->error = -ETIMEDOUT;
+	else if (stat & TMIO_STAT_CRCFAIL && cmd->flags & MMC_RSP_CRC)
+		cmd->error = -EILSEQ;
+
+	/* If there is data to handle we enable data IRQs here, and
+	 * we will ultimatley finish the request in the data_end handler.
+	 * If theres no data or we encountered an error, finish now.
+	 */
+	if (host->data && !cmd->error) {
+		if (host->data->flags & MMC_DATA_READ) {
+			if (host->force_pio || !host->chan_rx)
+				tmio_mmc_enable_mmc_irqs(host, TMIO_MASK_READOP);
+			else
+				tasklet_schedule(&host->dma_issue);
+		} else {
+			if (host->force_pio || !host->chan_tx)
+				tmio_mmc_enable_mmc_irqs(host, TMIO_MASK_WRITEOP);
+			else
+				tasklet_schedule(&host->dma_issue);
+		}
+	} else {
+		tmio_mmc_finish_request(host);
+	}
+
+out:
+	spin_unlock(&host->lock);
+}
+
+static irqreturn_t tmio_mmc_irq(int irq, void *devid)
+{
+	struct tmio_mmc_host *host = devid;
+	struct tmio_mmc_data *pdata = host->pdata;
+	unsigned int ireg, irq_mask, status;
+	unsigned int sdio_ireg, sdio_irq_mask, sdio_status;
+
+	pr_debug("MMC IRQ begin\n");
+
+	status = sd_ctrl_read32(host, CTL_STATUS);
+	irq_mask = sd_ctrl_read32(host, CTL_IRQ_MASK);
+	ireg = status & TMIO_MASK_IRQ & ~irq_mask;
+
+	sdio_ireg = 0;
+	if (!ireg && pdata->flags & TMIO_MMC_SDIO_IRQ) {
+		sdio_status = sd_ctrl_read16(host, CTL_SDIO_STATUS);
+		sdio_irq_mask = sd_ctrl_read16(host, CTL_SDIO_IRQ_MASK);
+		sdio_ireg = sdio_status & TMIO_SDIO_MASK_ALL & ~sdio_irq_mask;
+
+		sd_ctrl_write16(host, CTL_SDIO_STATUS, sdio_status & ~TMIO_SDIO_MASK_ALL);
+
+		if (sdio_ireg && !host->sdio_irq_enabled) {
+			pr_warning("tmio_mmc: Spurious SDIO IRQ, disabling! 0x%04x 0x%04x 0x%04x\n",
+				   sdio_status, sdio_irq_mask, sdio_ireg);
+			tmio_mmc_enable_sdio_irq(host->mmc, 0);
+			goto out;
+		}
+
+		if (host->mmc->caps & MMC_CAP_SDIO_IRQ &&
+			sdio_ireg & TMIO_SDIO_STAT_IOIRQ)
+			mmc_signal_sdio_irq(host->mmc);
+
+		if (sdio_ireg)
+			goto out;
+	}
+
+	pr_debug_status(status);
+	pr_debug_status(ireg);
+
+	if (!ireg) {
+		tmio_mmc_disable_mmc_irqs(host, status & ~irq_mask);
+
+		pr_warning("tmio_mmc: Spurious irq, disabling! "
+			"0x%08x 0x%08x 0x%08x\n", status, irq_mask, ireg);
+		pr_debug_status(status);
+
+		goto out;
+	}
+
+	while (ireg) {
+		/* Card insert / remove attempts */
+		if (ireg & (TMIO_STAT_CARD_INSERT | TMIO_STAT_CARD_REMOVE)) {
+			tmio_mmc_ack_mmc_irqs(host, TMIO_STAT_CARD_INSERT |
+				TMIO_STAT_CARD_REMOVE);
+			mmc_detect_change(host->mmc, msecs_to_jiffies(100));
+		}
+
+		/* CRC and other errors */
+/*		if (ireg & TMIO_STAT_ERR_IRQ)
+ *			handled |= tmio_error_irq(host, irq, stat);
+ */
+
+		/* Command completion */
+		if (ireg & (TMIO_STAT_CMDRESPEND | TMIO_STAT_CMDTIMEOUT)) {
+			tmio_mmc_ack_mmc_irqs(host,
+				     TMIO_STAT_CMDRESPEND |
+				     TMIO_STAT_CMDTIMEOUT);
+			tmio_mmc_cmd_irq(host, status);
+		}
+
+		/* Data transfer */
+		if (ireg & (TMIO_STAT_RXRDY | TMIO_STAT_TXRQ)) {
+			tmio_mmc_ack_mmc_irqs(host, TMIO_STAT_RXRDY | TMIO_STAT_TXRQ);
+			tmio_mmc_pio_irq(host);
+		}
+
+		/* Data transfer completion */
+		if (ireg & TMIO_STAT_DATAEND) {
+			tmio_mmc_ack_mmc_irqs(host, TMIO_STAT_DATAEND);
+			tmio_mmc_data_irq(host);
+		}
+
+		/* Check status - keep going until we've handled it all */
+		status = sd_ctrl_read32(host, CTL_STATUS);
+		irq_mask = sd_ctrl_read32(host, CTL_IRQ_MASK);
+		ireg = status & TMIO_MASK_IRQ & ~irq_mask;
+
+		pr_debug("Status at end of loop: %08x\n", status);
+		pr_debug_status(status);
+	}
+	pr_debug("MMC IRQ end\n");
+
+out:
+	return IRQ_HANDLED;
+}
+
+static int tmio_mmc_start_data(struct tmio_mmc_host *host,
+	struct mmc_data *data)
+{
+	struct tmio_mmc_data *pdata = host->pdata;
+
+	pr_debug("setup data transfer: blocksize %08x  nr_blocks %d\n",
+		 data->blksz, data->blocks);
+
+	/* Some hardware cannot perform 2 byte requests in 4 bit mode */
+	if (host->mmc->ios.bus_width == MMC_BUS_WIDTH_4) {
+		int blksz_2bytes = pdata->flags & TMIO_MMC_BLKSZ_2BYTES;
+
+		if (data->blksz < 2 || (data->blksz < 4 && !blksz_2bytes)) {
+			pr_err("%s: %d byte block unsupported in 4 bit mode\n",
+			       mmc_hostname(host->mmc), data->blksz);
+			return -EINVAL;
+		}
+	}
+
+	tmio_mmc_init_sg(host, data);
+	host->data = data;
+
+	/* Set transfer length / blocksize */
+	sd_ctrl_write16(host, CTL_SD_XFER_LEN, data->blksz);
+	sd_ctrl_write16(host, CTL_XFER_BLK_COUNT, data->blocks);
+
+	tmio_mmc_start_dma(host, data);
+
+	return 0;
+}
+
+/* Process requests from the MMC layer */
+static void tmio_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
+{
+	struct tmio_mmc_host *host = mmc_priv(mmc);
+	int ret;
+
+	if (host->mrq)
+		pr_debug("request not null\n");
+
+	host->last_req_ts = jiffies;
+	wmb();
+	host->mrq = mrq;
+
+	if (mrq->data) {
+		ret = tmio_mmc_start_data(host, mrq->data);
+		if (ret)
+			goto fail;
+	}
+
+	ret = tmio_mmc_start_command(host, mrq->cmd);
+	if (!ret) {
+		schedule_delayed_work(&host->delayed_reset_work,
+				      msecs_to_jiffies(2000));
+		return;
+	}
+
+fail:
+	host->mrq = NULL;
+	host->force_pio = false;
+	mrq->cmd->error = ret;
+	mmc_request_done(mmc, mrq);
+}
+
+/* Set MMC clock / power.
+ * Note: This controller uses a simple divider scheme therefore it cannot
+ * run a MMC card at full speed (20MHz). The max clock is 24MHz on SD, but as
+ * MMC wont run that fast, it has to be clocked at 12MHz which is the next
+ * slowest setting.
+ */
+static void tmio_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
+{
+	struct tmio_mmc_host *host = mmc_priv(mmc);
+
+	if (ios->clock)
+		tmio_mmc_set_clock(host, ios->clock);
+
+	/* Power sequence - OFF -> ON -> UP */
+	switch (ios->power_mode) {
+	case MMC_POWER_OFF: /* power down SD bus */
+		if (host->set_pwr)
+			host->set_pwr(host->pdev, 0);
+		tmio_mmc_clk_stop(host);
+		break;
+	case MMC_POWER_ON: /* power up SD bus */
+		if (host->set_pwr)
+			host->set_pwr(host->pdev, 1);
+		break;
+	case MMC_POWER_UP: /* start bus clock */
+		tmio_mmc_clk_start(host);
+		break;
+	}
+
+	switch (ios->bus_width) {
+	case MMC_BUS_WIDTH_1:
+		sd_ctrl_write16(host, CTL_SD_MEM_CARD_OPT, 0x80e0);
+	break;
+	case MMC_BUS_WIDTH_4:
+		sd_ctrl_write16(host, CTL_SD_MEM_CARD_OPT, 0x00e0);
+	break;
+	}
+
+	/* Let things settle. delay taken from winCE driver */
+	udelay(140);
+}
+
+static int tmio_mmc_get_ro(struct mmc_host *mmc)
+{
+	struct tmio_mmc_host *host = mmc_priv(mmc);
+	struct tmio_mmc_data *pdata = host->pdata;
+
+	return ((pdata->flags & TMIO_MMC_WRPROTECT_DISABLE) ||
+		!(sd_ctrl_read32(host, CTL_STATUS) & TMIO_STAT_WRPROTECT));
+}
+
+static int tmio_mmc_get_cd(struct mmc_host *mmc)
+{
+	struct tmio_mmc_host *host = mmc_priv(mmc);
+	struct tmio_mmc_data *pdata = host->pdata;
+
+	if (!pdata->get_cd)
+		return -ENOSYS;
+	else
+		return pdata->get_cd(host->pdev);
+}
+
+static const struct mmc_host_ops tmio_mmc_ops = {
+	.request	= tmio_mmc_request,
+	.set_ios	= tmio_mmc_set_ios,
+	.get_ro         = tmio_mmc_get_ro,
+	.get_cd		= tmio_mmc_get_cd,
+	.enable_sdio_irq = tmio_mmc_enable_sdio_irq,
+};
+
+int __devinit tmio_mmc_host_probe(struct tmio_mmc_host **host,
+				  struct platform_device *pdev,
+				  struct tmio_mmc_data *pdata)
+{
+	struct tmio_mmc_host *_host;
+	struct mmc_host *mmc;
+	struct resource *res_ctl;
+	int ret;
+	u32 irq_mask = TMIO_MASK_CMD;
+
+	res_ctl = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res_ctl)
+		return -EINVAL;
+
+	mmc = mmc_alloc_host(sizeof(struct tmio_mmc_host), &pdev->dev);
+	if (!mmc)
+		return -ENOMEM;
+
+	_host = mmc_priv(mmc);
+	_host->pdata = pdata;
+	_host->mmc = mmc;
+	_host->pdev = pdev;
+	platform_set_drvdata(pdev, mmc);
+
+	_host->set_pwr = pdata->set_pwr;
+	_host->set_clk_div = pdata->set_clk_div;
+
+	/* SD control register space size is 0x200, 0x400 for bus_shift=1 */
+	_host->bus_shift = resource_size(res_ctl) >> 10;
+
+	_host->ctl = ioremap(res_ctl->start, resource_size(res_ctl));
+	if (!_host->ctl) {
+		ret = -ENOMEM;
+		goto host_free;
+	}
+
+	mmc->ops = &tmio_mmc_ops;
+	mmc->caps = MMC_CAP_4_BIT_DATA | pdata->capabilities;
+	mmc->f_max = pdata->hclk;
+	mmc->f_min = mmc->f_max / 512;
+	mmc->max_segs = 32;
+	mmc->max_blk_size = 512;
+	mmc->max_blk_count = (PAGE_CACHE_SIZE / mmc->max_blk_size) *
+		mmc->max_segs;
+	mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
+	mmc->max_seg_size = mmc->max_req_size;
+	if (pdata->ocr_mask)
+		mmc->ocr_avail = pdata->ocr_mask;
+	else
+		mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
+
+	tmio_mmc_clk_stop(_host);
+	tmio_mmc_reset(_host);
+
+	ret = platform_get_irq(pdev, 0);
+	if (ret < 0)
+		goto unmap_ctl;
+
+	_host->irq = ret;
+
+	tmio_mmc_disable_mmc_irqs(_host, TMIO_MASK_ALL);
+	if (pdata->flags & TMIO_MMC_SDIO_IRQ)
+		tmio_mmc_enable_sdio_irq(mmc, 0);
+
+	ret = request_irq(_host->irq, tmio_mmc_irq, IRQF_DISABLED |
+		IRQF_TRIGGER_FALLING, dev_name(&pdev->dev), _host);
+	if (ret)
+		goto unmap_ctl;
+
+	spin_lock_init(&_host->lock);
+
+	/* Init delayed work for request timeouts */
+	INIT_DELAYED_WORK(&_host->delayed_reset_work, tmio_mmc_reset_work);
+
+	/* See if we also get DMA */
+	tmio_mmc_request_dma(_host, pdata);
+
+	mmc_add_host(mmc);
+
+	/* Unmask the IRQs we want to know about */
+	if (!_host->chan_rx)
+		irq_mask |= TMIO_MASK_READOP;
+	if (!_host->chan_tx)
+		irq_mask |= TMIO_MASK_WRITEOP;
+
+	tmio_mmc_enable_mmc_irqs(_host, irq_mask);
+
+	*host = _host;
+
+	return 0;
+
+unmap_ctl:
+	iounmap(_host->ctl);
+host_free:
+	mmc_free_host(mmc);
+
+	return ret;
+}
+EXPORT_SYMBOL(tmio_mmc_host_probe);
+
+void tmio_mmc_host_remove(struct tmio_mmc_host *host)
+{
+	mmc_remove_host(host->mmc);
+	cancel_delayed_work_sync(&host->delayed_reset_work);
+	tmio_mmc_release_dma(host);
+	free_irq(host->irq, host);
+	iounmap(host->ctl);
+	mmc_free_host(host->mmc);
+}
+EXPORT_SYMBOL(tmio_mmc_host_remove);
+
+MODULE_LICENSE("GPL v2");