mfd: TMIO MMC driver

This patch adds support for the MMC subdevice 'cell' commonly found in
TMIO based MFDs.
Signed-off-by: Ian Molton <spyro@f2s.com>
Acked-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Samuel Ortiz <sameo@openedhand.com>

drivers/mmc/host/Kconfig

@@ -174,3 +174,9 @@ config MMC_SDRICOH_CS
 	  To compile this driver as a module, choose M here: the
 	  module will be called sdricoh_cs.
 
+config MMC_TMIO
+	tristate "Toshiba Mobile IO Controller (TMIO) MMC/SD function support"
+	depends on MFD_CORE
+	help
+	  This provides support for the SD/MMC cell found in TC6393XB,
+	  T7L66XB and also ipaq ASIC3

drivers/mmc/host/Makefile

@@ -21,4 +21,5 @@ obj-$(CONFIG_MMC_TIFM_SD)	+= tifm_sd.o
 obj-$(CONFIG_MMC_SPI)		+= mmc_spi.o
 obj-$(CONFIG_MMC_S3C)   	+= s3cmci.o
 obj-$(CONFIG_MMC_SDRICOH_CS)	+= sdricoh_cs.o
+obj-$(CONFIG_MMC_TMIO)		+= tmio_mmc.o
 

drivers/mmc/host/tmio_mmc.c

+/*
+ *  linux/drivers/mmc/tmio_mmc.c
+ *
+ *  Copyright (C) 2004 Ian Molton
+ *  Copyright (C) 2007 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 cell found in:
+ *
+ * TC6393XB TC6391XB TC6387XB T7L66XB
+ *
+ * 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/module.h>
+#include <linux/irq.h>
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/mmc/host.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/tmio.h>
+
+#include "tmio_mmc.h"
+
+/*
+ * Fixme - documentation conflicts on what the clock values are for the
+ * various dividers.
+ * One document I have says that its a divisor of a 24MHz clock, another 33.
+ * This probably depends on HCLK for a given platform, so we may need to
+ * require HCLK be passed to us from the MFD core.
+ *
+ */
+
+static void tmio_mmc_set_clock(struct tmio_mmc_host *host, int new_clock)
+{
+	void __iomem *cnf = host->cnf;
+	void __iomem *ctl = host->ctl;
+	u32 clk = 0, clock;
+
+	if (new_clock) {
+		for (clock = 46875, clk = 0x100; new_clock >= (clock<<1); ) {
+			clock <<= 1;
+			clk >>= 1;
+		}
+		if (clk & 0x1)
+			clk = 0x20000;
+
+		clk >>= 2;
+		tmio_iowrite8((clk & 0x8000) ? 0 : 1, cnf + CNF_SD_CLK_MODE);
+		clk |= 0x100;
+	}
+
+	tmio_iowrite16(clk, ctl + CTL_SD_CARD_CLK_CTL);
+}
+
+static void tmio_mmc_clk_stop(struct tmio_mmc_host *host)
+{
+	void __iomem *ctl = host->ctl;
+
+	tmio_iowrite16(0x0000, ctl + CTL_CLK_AND_WAIT_CTL);
+	msleep(10);
+	tmio_iowrite16(tmio_ioread16(ctl + CTL_SD_CARD_CLK_CTL) & ~0x0100,
+	       ctl + CTL_SD_CARD_CLK_CTL);
+	msleep(10);
+}
+
+static void tmio_mmc_clk_start(struct tmio_mmc_host *host)
+{
+	void __iomem *ctl = host->ctl;
+
+	tmio_iowrite16(tmio_ioread16(ctl + CTL_SD_CARD_CLK_CTL) | 0x0100,
+	       ctl + CTL_SD_CARD_CLK_CTL);
+	msleep(10);
+	tmio_iowrite16(0x0100, ctl + CTL_CLK_AND_WAIT_CTL);
+	msleep(10);
+}
+
+static void reset(struct tmio_mmc_host *host)
+{
+	void __iomem *ctl = host->ctl;
+
+	/* FIXME - should we set stop clock reg here */
+	tmio_iowrite16(0x0000, ctl + CTL_RESET_SD);
+	tmio_iowrite16(0x0000, ctl + CTL_RESET_SDIO);
+	msleep(10);
+	tmio_iowrite16(0x0001, ctl + CTL_RESET_SD);
+	tmio_iowrite16(0x0001, ctl + CTL_RESET_SDIO);
+	msleep(10);
+}
+
+static void
+tmio_mmc_finish_request(struct tmio_mmc_host *host)
+{
+	struct mmc_request *mrq = host->mrq;
+
+	host->mrq = NULL;
+	host->cmd = NULL;
+	host->data = NULL;
+
+	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)
+{
+	void __iomem *ctl = host->ctl;
+	struct mmc_data *data = host->data;
+	int c = cmd->opcode;
+
+	/* Command 12 is handled by hardware */
+	if (cmd->opcode == 12 && !cmd->arg) {
+		tmio_iowrite16(0x001, ctl + CTL_STOP_INTERNAL_ACTION);
+		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 comented 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) {
+			tmio_iowrite16(0x100, ctl + CTL_STOP_INTERNAL_ACTION);
+			c |= TRANSFER_MULTI;
+		}
+		if (data->flags & MMC_DATA_READ)
+			c |= TRANSFER_READ;
+	}
+
+	enable_mmc_irqs(ctl, TMIO_MASK_CMD);
+
+	/* Fire off the command */
+	tmio_iowrite32(cmd->arg, ctl + CTL_ARG_REG);
+	tmio_iowrite16(c, ctl + CTL_SD_CMD);
+
+	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 inline void tmio_mmc_pio_irq(struct tmio_mmc_host *host)
+{
+	void __iomem *ctl = host->ctl;
+	struct mmc_data *data = host->data;
+	unsigned short *buf;
+	unsigned int count;
+	unsigned long flags;
+
+	if (!data) {
+		pr_debug("Spurious PIO IRQ\n");
+		return;
+	}
+
+	buf = (unsigned short *)(tmio_mmc_kmap_atomic(host, &flags) +
+	      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)
+		tmio_ioread16_rep(ctl + CTL_SD_DATA_PORT, buf, count >> 1);
+	else
+		tmio_iowrite16_rep(ctl + CTL_SD_DATA_PORT, buf, count >> 1);
+
+	host->sg_off += count;
+
+	tmio_mmc_kunmap_atomic(host, &flags);
+
+	if (host->sg_off == host->sg_ptr->length)
+		tmio_mmc_next_sg(host);
+
+	return;
+}
+
+static inline void tmio_mmc_data_irq(struct tmio_mmc_host *host)
+{
+	void __iomem *ctl = host->ctl;
+	struct mmc_data *data = host->data;
+	struct mmc_command *stop = data->stop;
+
+	host->data = NULL;
+
+	if (!data) {
+		pr_debug("Spurious data end IRQ\n");
+		return;
+	}
+
+	/* 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)
+		disable_mmc_irqs(ctl, TMIO_MASK_READOP);
+	else
+		disable_mmc_irqs(ctl, TMIO_MASK_WRITEOP);
+
+	if (stop) {
+		if (stop->opcode == 12 && !stop->arg)
+			tmio_iowrite16(0x000, ctl + CTL_STOP_INTERNAL_ACTION);
+		else
+			BUG();
+	}
+
+	tmio_mmc_finish_request(host);
+}
+
+static inline void tmio_mmc_cmd_irq(struct tmio_mmc_host *host,
+	unsigned int stat)
+{
+	void __iomem *ctl = host->ctl, *addr;
+	struct mmc_command *cmd = host->cmd;
+	int i;
+
+	if (!host->cmd) {
+		pr_debug("Spurious CMD irq\n");
+		return;
+	}
+
+	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 + CTL_RESPONSE ; i >= 0 ; i--, addr += 4)
+		cmd->resp[i] = tmio_ioread32(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)
+			enable_mmc_irqs(ctl, TMIO_MASK_READOP);
+		else
+			enable_mmc_irqs(ctl, TMIO_MASK_WRITEOP);
+	} else {
+		tmio_mmc_finish_request(host);
+	}
+
+	return;
+}
+
+
+static irqreturn_t tmio_mmc_irq(int irq, void *devid)
+{
+	struct tmio_mmc_host *host = devid;
+	void __iomem *ctl = host->ctl;
+	unsigned int ireg, irq_mask, status;
+
+	pr_debug("MMC IRQ begin\n");
+
+	status = tmio_ioread32(ctl + CTL_STATUS);
+	irq_mask = tmio_ioread32(ctl + CTL_IRQ_MASK);
+	ireg = status & TMIO_MASK_IRQ & ~irq_mask;
+
+	pr_debug_status(status);
+	pr_debug_status(ireg);
+
+	if (!ireg) {
+		disable_mmc_irqs(ctl, status & ~irq_mask);
+
+		pr_debug("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)) {
+			ack_mmc_irqs(ctl, TMIO_STAT_CARD_INSERT |
+				TMIO_STAT_CARD_REMOVE);
+			mmc_detect_change(host->mmc, 0);
+		}
+
+		/* CRC and other errors */
+/*		if (ireg & TMIO_STAT_ERR_IRQ)
+ *			handled |= tmio_error_irq(host, irq, stat);
+ */
+
+		/* Command completion */
+		if (ireg & TMIO_MASK_CMD) {
+			ack_mmc_irqs(ctl, TMIO_MASK_CMD);
+			tmio_mmc_cmd_irq(host, status);
+		}
+
+		/* Data transfer */
+		if (ireg & (TMIO_STAT_RXRDY | TMIO_STAT_TXRQ)) {
+			ack_mmc_irqs(ctl, TMIO_STAT_RXRDY | TMIO_STAT_TXRQ);
+			tmio_mmc_pio_irq(host);
+		}
+
+		/* Data transfer completion */
+		if (ireg & TMIO_STAT_DATAEND) {
+			ack_mmc_irqs(ctl, TMIO_STAT_DATAEND);
+			tmio_mmc_data_irq(host);
+		}
+
+		/* Check status - keep going until we've handled it all */
+		status = tmio_ioread32(ctl + CTL_STATUS);
+		irq_mask = tmio_ioread32(ctl + 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)
+{
+	void __iomem *ctl = host->ctl;
+
+	pr_debug("setup data transfer: blocksize %08x  nr_blocks %d\n",
+	    data->blksz, data->blocks);
+
+	/* Hardware cannot perform 1 and 2 byte requests in 4 bit mode */
+	if (data->blksz < 4 && host->mmc->ios.bus_width == MMC_BUS_WIDTH_4) {
+		printk(KERN_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 */
+	tmio_iowrite16(data->blksz,  ctl + CTL_SD_XFER_LEN);
+	tmio_iowrite16(data->blocks, ctl + CTL_XFER_BLK_COUNT);
+
+	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->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)
+		return;
+
+fail:
+	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);
+	void __iomem *cnf = host->cnf;
+	void __iomem *ctl = host->ctl;
+
+	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 */
+		tmio_iowrite8(0x00, cnf + CNF_PWR_CTL_2);
+		tmio_mmc_clk_stop(host);
+		break;
+	case MMC_POWER_ON: /* power up SD bus */
+
+		tmio_iowrite8(0x02, cnf + CNF_PWR_CTL_2);
+		break;
+	case MMC_POWER_UP: /* start bus clock */
+		tmio_mmc_clk_start(host);
+		break;
+	}
+
+	switch (ios->bus_width) {
+	case MMC_BUS_WIDTH_1:
+		tmio_iowrite16(0x80e0, ctl + CTL_SD_MEM_CARD_OPT);
+	break;
+	case MMC_BUS_WIDTH_4:
+		tmio_iowrite16(0x00e0, ctl + CTL_SD_MEM_CARD_OPT);
+	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);
+	void __iomem *ctl = host->ctl;
+
+	return (tmio_ioread16(ctl + CTL_STATUS) & TMIO_STAT_WRPROTECT) ? 0 : 1;
+}
+
+static struct mmc_host_ops tmio_mmc_ops = {
+	.request	= tmio_mmc_request,
+	.set_ios	= tmio_mmc_set_ios,
+	.get_ro         = tmio_mmc_get_ro,
+};
+
+#ifdef CONFIG_PM
+static int tmio_mmc_suspend(struct platform_device *dev, pm_message_t state)
+{
+	struct mfd_cell	*cell = (struct mfd_cell *)dev->dev.platform_data;
+	struct mmc_host *mmc = platform_get_drvdata(dev);
+	int ret;
+
+	ret = mmc_suspend_host(mmc, state);
+
+	/* Tell MFD core it can disable us now.*/
+	if (!ret && cell->disable)
+		cell->disable(dev);
+
+	return ret;
+}
+
+static int tmio_mmc_resume(struct platform_device *dev)
+{
+	struct mfd_cell	*cell = (struct mfd_cell *)dev->dev.platform_data;
+	struct mmc_host *mmc = platform_get_drvdata(dev);
+	struct tmio_mmc_host *host = mmc_priv(mmc);
+	void __iomem *cnf = host->cnf;
+	int ret = 0;
+
+	/* Enable the MMC/SD Control registers */
+	tmio_iowrite16(SDCREN, cnf + CNF_CMD);
+	tmio_iowrite32(dev->resource[0].start & 0xfffe, cnf + CNF_CTL_BASE);
+
+	/* Tell the MFD core we are ready to be enabled */
+	if (cell->enable) {
+		ret = cell->enable(dev);
+		if (ret)
+			goto out;
+	}
+
+	mmc_resume_host(mmc);
+
+out:
+	return ret;
+}
+#else
+#define tmio_mmc_suspend NULL
+#define tmio_mmc_resume NULL
+#endif
+
+static int __devinit tmio_mmc_probe(struct platform_device *dev)
+{
+	struct mfd_cell	*cell = (struct mfd_cell *)dev->dev.platform_data;
+	struct resource *res_ctl, *res_cnf;
+	struct tmio_mmc_host *host;
+	struct mmc_host *mmc;
+	int ret = -ENOMEM;
+
+	if (dev->num_resources != 3)
+		goto out;
+
+	res_ctl = platform_get_resource(dev, IORESOURCE_MEM, 0);
+	res_cnf = platform_get_resource(dev, IORESOURCE_MEM, 1);
+	if (!res_ctl || !res_cnf) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	mmc = mmc_alloc_host(sizeof(struct tmio_mmc_host), &dev->dev);
+	if (!mmc)
+		goto out;
+
+	host = mmc_priv(mmc);
+	host->mmc = mmc;
+	platform_set_drvdata(dev, mmc);
+
+	host->ctl = ioremap(res_ctl->start, res_ctl->end - res_ctl->start);
+	if (!host->ctl)
+		goto host_free;
+
+	host->cnf = ioremap(res_cnf->start, res_cnf->end - res_cnf->start);
+	if (!host->cnf)
+		goto unmap_ctl;
+
+	mmc->ops = &tmio_mmc_ops;
+	mmc->caps = MMC_CAP_4_BIT_DATA;
+	mmc->f_min = 46875; /* 24000000 / 512 */
+	mmc->f_max = 24000000;
+	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
+
+	/* Enable the MMC/SD Control registers */
+	tmio_iowrite16(SDCREN, host->cnf + CNF_CMD);
+	tmio_iowrite32(dev->resource[0].start & 0xfffe,
+		host->cnf + CNF_CTL_BASE);
+
+	/* Tell the MFD core we are ready to be enabled */
+	if (cell->enable) {
+		ret = cell->enable(dev);
+		if (ret)
+			goto unmap_cnf;
+	}
+
+	/* Disable SD power during suspend */
+	tmio_iowrite8(0x01, host->cnf + CNF_PWR_CTL_3);
+
+	/* The below is required but why? FIXME */
+	tmio_iowrite8(0x1f, host->cnf + CNF_STOP_CLK_CTL);
+
+	/* Power down SD bus*/
+	tmio_iowrite8(0x0,  host->cnf + CNF_PWR_CTL_2);
+
+	tmio_mmc_clk_stop(host);
+	reset(host);
+
+	ret = platform_get_irq(dev, 0);
+	if (ret >= 0)
+		host->irq = ret;
+	else
+		goto unmap_cnf;
+
+	disable_mmc_irqs(host->ctl, TMIO_MASK_ALL);
+
+	ret = request_irq(host->irq, tmio_mmc_irq, IRQF_DISABLED, "tmio-mmc",
+		host);
+	if (ret)
+		goto unmap_cnf;
+
+	set_irq_type(host->irq, IRQ_TYPE_EDGE_FALLING);
+
+	mmc_add_host(mmc);
+
+	printk(KERN_INFO "%s at 0x%08lx irq %d\n", mmc_hostname(host->mmc),
+	       (unsigned long)host->ctl, host->irq);
+
+	/* Unmask the IRQs we want to know about */
+	enable_mmc_irqs(host->ctl,  TMIO_MASK_IRQ);
+
+	return 0;
+
+unmap_cnf:
+	iounmap(host->cnf);
+unmap_ctl:
+	iounmap(host->ctl);
+host_free:
+	mmc_free_host(mmc);
+out:
+	return ret;
+}
+
+static int __devexit tmio_mmc_remove(struct platform_device *dev)
+{
+	struct mmc_host *mmc = platform_get_drvdata(dev);
+
+	platform_set_drvdata(dev, NULL);
+
+	if (mmc) {
+		struct tmio_mmc_host *host = mmc_priv(mmc);
+		mmc_remove_host(mmc);
+		mmc_free_host(mmc);
+		free_irq(host->irq, host);
+		iounmap(host->ctl);
+		iounmap(host->cnf);
+	}
+
+	return 0;
+}
+
+/* ------------------- device registration ----------------------- */
+
+static struct platform_driver tmio_mmc_driver = {
+	.driver = {
+		.name = "tmio-mmc",
+		.owner = THIS_MODULE,
+	},
+	.probe = tmio_mmc_probe,
+	.remove = __devexit_p(tmio_mmc_remove),
+	.suspend = tmio_mmc_suspend,
+	.resume = tmio_mmc_resume,
+};
+
+
+static int __init tmio_mmc_init(void)
+{
+	return platform_driver_register(&tmio_mmc_driver);
+}
+
+static void __exit tmio_mmc_exit(void)
+{
+	platform_driver_unregister(&tmio_mmc_driver);
+}
+
+module_init(tmio_mmc_init);
+module_exit(tmio_mmc_exit);
+
+MODULE_DESCRIPTION("Toshiba TMIO SD/MMC driver");
+MODULE_AUTHOR("Ian Molton <spyro@f2s.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:tmio-mmc");

drivers/mmc/host/tmio_mmc.h

+/* Definitons for use with the tmio_mmc.c
+ *
+ * (c) 2004 Ian Molton <spyro@f2s.com>
+ * (c) 2007 Ian Molton <spyro@f2s.com>
+ *
+ * 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.
+ *
+ */
+#define CNF_CMD     0x04
+#define CNF_CTL_BASE   0x10
+#define CNF_INT_PIN  0x3d
+#define CNF_STOP_CLK_CTL 0x40
+#define CNF_GCLK_CTL 0x41
+#define CNF_SD_CLK_MODE 0x42
+#define CNF_PIN_STATUS 0x44
+#define CNF_PWR_CTL_1 0x48
+#define CNF_PWR_CTL_2 0x49
+#define CNF_PWR_CTL_3 0x4a
+#define CNF_CARD_DETECT_MODE 0x4c
+#define CNF_SD_SLOT 0x50
+#define CNF_EXT_GCLK_CTL_1 0xf0
+#define CNF_EXT_GCLK_CTL_2 0xf1
+#define CNF_EXT_GCLK_CTL_3 0xf9
+#define CNF_SD_LED_EN_1 0xfa
+#define CNF_SD_LED_EN_2 0xfe
+
+#define   SDCREN 0x2   /* Enable access to MMC CTL regs. (flag in COMMAND_REG)*/
+
+#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_RESET_SD 0xe0
+#define CTL_SDIO_REGS 0x100
+#define CTL_CLK_AND_WAIT_CTL 0x138
+#define CTL_RESET_SDIO 0x1e0
+
+/* Definitions for values the CTRL_STATUS register can take. */
+#define TMIO_STAT_CMDRESPEND    0x00000001
+#define TMIO_STAT_DATAEND       0x00000004
+#define TMIO_STAT_CARD_REMOVE   0x00000008
+#define TMIO_STAT_CARD_INSERT   0x00000010
+#define TMIO_STAT_SIGSTATE      0x00000020
+#define TMIO_STAT_WRPROTECT     0x00000080
+#define TMIO_STAT_CARD_REMOVE_A 0x00000100
+#define TMIO_STAT_CARD_INSERT_A 0x00000200
+#define TMIO_STAT_SIGSTATE_A    0x00000400
+#define TMIO_STAT_CMD_IDX_ERR   0x00010000
+#define TMIO_STAT_CRCFAIL       0x00020000
+#define TMIO_STAT_STOPBIT_ERR   0x00040000
+#define TMIO_STAT_DATATIMEOUT   0x00080000
+#define TMIO_STAT_RXOVERFLOW    0x00100000
+#define TMIO_STAT_TXUNDERRUN    0x00200000
+#define TMIO_STAT_CMDTIMEOUT    0x00400000
+#define TMIO_STAT_RXRDY         0x01000000
+#define TMIO_STAT_TXRQ          0x02000000
+#define TMIO_STAT_ILL_FUNC      0x20000000
+#define TMIO_STAT_CMD_BUSY      0x40000000
+#define TMIO_STAT_ILL_ACCESS    0x80000000
+
+/* Define some IRQ masks */
+/* This is the mask used at reset by the chip */
+#define TMIO_MASK_ALL           0x837f031d
+#define TMIO_MASK_READOP  (TMIO_STAT_RXRDY | TMIO_STAT_DATAEND | \
+		TMIO_STAT_CARD_REMOVE | TMIO_STAT_CARD_INSERT)
+#define TMIO_MASK_WRITEOP (TMIO_STAT_TXRQ | TMIO_STAT_DATAEND | \
+		TMIO_STAT_CARD_REMOVE | TMIO_STAT_CARD_INSERT)
+#define TMIO_MASK_CMD     (TMIO_STAT_CMDRESPEND | TMIO_STAT_CMDTIMEOUT | \
+		TMIO_STAT_CARD_REMOVE | TMIO_STAT_CARD_INSERT)
+#define TMIO_MASK_IRQ     (TMIO_MASK_READOP | TMIO_MASK_WRITEOP | TMIO_MASK_CMD)
+
+#define enable_mmc_irqs(ctl, i) \
+	do { \
+		u32 mask;\
+		mask  = tmio_ioread32((ctl) + CTL_IRQ_MASK); \
+		mask &= ~((i) & TMIO_MASK_IRQ); \
+		tmio_iowrite32(mask, (ctl) + CTL_IRQ_MASK); \
+	} while (0)
+
+#define disable_mmc_irqs(ctl, i) \
+	do { \
+		u32 mask;\
+		mask  = tmio_ioread32((ctl) + CTL_IRQ_MASK); \
+		mask |= ((i) & TMIO_MASK_IRQ); \
+		tmio_iowrite32(mask, (ctl) + CTL_IRQ_MASK); \
+	} while (0)
+
+#define ack_mmc_irqs(ctl, i) \
+	do { \
+		u32 mask;\
+		mask  = tmio_ioread32((ctl) + CTL_STATUS); \
+		mask &= ~((i) & TMIO_MASK_IRQ); \
+		tmio_iowrite32(mask, (ctl) + CTL_STATUS); \
+	} while (0)
+
+
+struct tmio_mmc_host {
+	void __iomem *cnf;
+	void __iomem *ctl;
+	struct mmc_command      *cmd;
+	struct mmc_request      *mrq;
+	struct mmc_data         *data;
+	struct mmc_host         *mmc;
+	int                     irq;
+
+	/* pio related stuff */
+	struct scatterlist      *sg_ptr;
+	unsigned int            sg_len;
+	unsigned int            sg_off;
+};
+
+#include <linux/scatterlist.h>
+#include <linux/blkdev.h>
+
+static inline 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_off = 0;
+}
+
+static inline 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;
+}
+
+static inline char *tmio_mmc_kmap_atomic(struct tmio_mmc_host *host,
+	unsigned long *flags)
+{
+	struct scatterlist *sg = host->sg_ptr;
+
+	local_irq_save(*flags);
+	return kmap_atomic(sg_page(sg), KM_BIO_SRC_IRQ) + sg->offset;
+}
+
+static inline void tmio_mmc_kunmap_atomic(struct tmio_mmc_host *host,
+	unsigned long *flags)
+{
+	kunmap_atomic(sg_page(host->sg_ptr), KM_BIO_SRC_IRQ);
+	local_irq_restore(*flags);
+}
+
+#ifdef CONFIG_MMC_DEBUG
+
+#define STATUS_TO_TEXT(a) \
+	do { \
+		if (status & TMIO_STAT_##a) \
+			printf(#a); \
+	} while (0)
+
+void debug_status(u32 status)
+{
+	printk(KERN_DEBUG "status: %08x = ", status);
+	STATUS_TO_TEXT(CARD_REMOVE);
+	STATUS_TO_TEXT(CARD_INSERT);
+	STATUS_TO_TEXT(SIGSTATE);
+	STATUS_TO_TEXT(WRPROTECT);
+	STATUS_TO_TEXT(CARD_REMOVE_A);
+	STATUS_TO_TEXT(CARD_INSERT_A);
+	STATUS_TO_TEXT(SIGSTATE_A);
+	STATUS_TO_TEXT(CMD_IDX_ERR);
+	STATUS_TO_TEXT(STOPBIT_ERR);
+	STATUS_TO_TEXT(ILL_FUNC);
+	STATUS_TO_TEXT(CMD_BUSY);
+	STATUS_TO_TEXT(CMDRESPEND);
+	STATUS_TO_TEXT(DATAEND);
+	STATUS_TO_TEXT(CRCFAIL);
+	STATUS_TO_TEXT(DATATIMEOUT);
+	STATUS_TO_TEXT(CMDTIMEOUT);
+	STATUS_TO_TEXT(RXOVERFLOW);
+	STATUS_TO_TEXT(TXUNDERRUN);
+	STATUS_TO_TEXT(RXRDY);
+	STATUS_TO_TEXT(TXRQ);
+	STATUS_TO_TEXT(ILL_ACCESS);
+	printk("\n");
+}
+
+#else
+#define pr_debug_status(s)  do { } while (0)
+#endif