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path: root/target/linux/goldfish/patches-2.6.30/0124--ARM-goldfish-mmc-goldfish-MMC-driver-building-an.patch
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From 2eccfcf4c5c50b412a0859a345d8d28fc043956b Mon Sep 17 00:00:00 2001
From: Mike Lockwood <lockwood@android.com>
Date: Thu, 7 Feb 2008 07:47:30 -0500
Subject: [PATCH 124/134] [ARM] goldfish: mmc: goldfish MMC driver building and runnning in 2.6.27.

Signed-off-by: Mike A. Chan <mikechan@google.com>
---
 drivers/mmc/host/Kconfig    |    8 +
 drivers/mmc/host/Makefile   |    1 +
 drivers/mmc/host/goldfish.c |  583 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 592 insertions(+), 0 deletions(-)
 create mode 100644 drivers/mmc/host/goldfish.c

--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -200,6 +200,14 @@ config MMC_MVSDIO
 	  To compile this driver as a module, choose M here: the
 	  module will be called mvsdio.
 
+config MMC_GOLDFISH
+	tristate "goldfish qemu Multimedia Card Interface support"
+	depends on ARCH_GOLDFISH
+	help
+	  This selects the Goldfish Multimedia card Interface emulation.
+
+	  If unsure, say N.
+
 config MMC_SPI
 	tristate "MMC/SD/SDIO over SPI"
 	depends on SPI_MASTER && !HIGHMEM && HAS_DMA
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -26,6 +26,7 @@ obj-$(CONFIG_MMC_SPI)		+= mmc_spi.o
 ifeq ($(CONFIG_OF),y)
 obj-$(CONFIG_MMC_SPI)		+= of_mmc_spi.o
 endif
+obj-$(CONFIG_MMC_GOLDFISH)	+= goldfish.o
 obj-$(CONFIG_MMC_S3C)   	+= s3cmci.o
 obj-$(CONFIG_MMC_SDRICOH_CS)	+= sdricoh_cs.o
 obj-$(CONFIG_MMC_TMIO)		+= tmio_mmc.o
--- /dev/null
+++ b/drivers/mmc/host/goldfish.c
@@ -0,0 +1,583 @@
+/*
+ *  linux/drivers/media/mmc/goldfish.c
+ *
+ *  Copyright 2007, Google Inc.
+ *
+ *  based on omap.c driver, which was
+ *  Copyright (C) 2004 Nokia Corporation
+ *  Written by Tuukka Tikkanen and Juha Yrjölä<juha.yrjola@nokia.com>
+ *  Misc hacks here and there by Tony Lindgren <tony@atomide.com>
+ *  Other hacks (DMA, SD, etc) by David Brownell
+ *
+ * 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/platform_device.h>
+#include <linux/major.h>
+
+#include <linux/types.h>
+#include <linux/pci.h>
+#include <linux/interrupt.h>
+
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/errno.h>
+#include <linux/hdreg.h>
+#include <linux/kdev_t.h>
+#include <linux/blkdev.h>
+#include <linux/mutex.h>
+#include <linux/scatterlist.h>
+#include <linux/mmc/mmc.h>
+#include <linux/mmc/sdio.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/card.h>
+
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/dma-mapping.h>
+#include <linux/delay.h>
+#include <linux/spinlock.h>
+#include <linux/timer.h>
+#include <linux/clk.h>
+
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/scatterlist.h>
+#include <asm/mach-types.h>
+
+
+#include <asm/types.h>
+#include <asm/io.h>
+#include <asm/uaccess.h>
+
+#define DRIVER_NAME "goldfish_mmc"
+
+#define BUFFER_SIZE   16384
+
+#define GOLDFISH_MMC_READ(host, addr)   (readl(host->reg_base + addr))
+#define GOLDFISH_MMC_WRITE(host, addr, x)   (writel(x, host->reg_base + addr))
+
+
+enum {
+	/* status register */
+	MMC_INT_STATUS	        = 0x00, 
+	/* set this to enable IRQ */
+	MMC_INT_ENABLE	        = 0x04,
+	/* set this to specify buffer address */
+	MMC_SET_BUFFER          = 0x08,
+	
+	/* MMC command number */
+	MMC_CMD	                = 0x0C,	
+
+	/* MMC argument */
+	MMC_ARG	                = 0x10,
+	
+	/* MMC response (or R2 bits 0 - 31) */
+	MMC_RESP_0		        = 0x14,
+
+	/* MMC R2 response bits 32 - 63 */
+	MMC_RESP_1		        = 0x18,
+
+	/* MMC R2 response bits 64 - 95 */
+	MMC_RESP_2		        = 0x1C,
+
+	/* MMC R2 response bits 96 - 127 */
+	MMC_RESP_3		        = 0x20,
+
+	MMC_BLOCK_LENGTH        = 0x24,
+	MMC_BLOCK_COUNT         = 0x28,
+
+	/* MMC state flags */
+	MMC_STATE               = 0x2C,
+
+	/* MMC_INT_STATUS bits */
+	
+	MMC_STAT_END_OF_CMD     = 1U << 0,
+	MMC_STAT_END_OF_DATA    = 1U << 1,
+	MMC_STAT_STATE_CHANGE   = 1U << 2,
+
+	/* MMC_STATE bits */
+	MMC_STATE_INSERTED     = 1U << 0,
+	MMC_STATE_READ_ONLY    = 1U << 1,
+};
+
+/*
+ * Command types
+ */
+#define OMAP_MMC_CMDTYPE_BC	0
+#define OMAP_MMC_CMDTYPE_BCR	1
+#define OMAP_MMC_CMDTYPE_AC	2
+#define OMAP_MMC_CMDTYPE_ADTC	3
+
+
+struct goldfish_mmc_host {
+	struct mmc_request *	mrq;
+	struct mmc_command *	cmd;
+	struct mmc_data *	data;
+	struct mmc_host *	mmc;
+	struct device *		dev;
+	unsigned char		id; /* 16xx chips have 2 MMC blocks */
+	void __iomem		*virt_base;
+	unsigned int		phys_base;
+	int			irq;
+	unsigned char		bus_mode;
+	unsigned char		hw_bus_mode;
+
+	unsigned int		sg_len;
+	unsigned		dma_done:1;
+	unsigned		dma_in_use:1;
+
+	struct work_struct	switch_work;
+	int			switch_last_state;
+
+	uint32_t			reg_base;
+};
+
+static inline int
+goldfish_mmc_cover_is_open(struct goldfish_mmc_host *host)
+{
+	return 0;
+}
+
+static ssize_t
+goldfish_mmc_show_cover_switch(struct device *dev,
+	struct device_attribute *attr, char *buf)
+{
+	struct goldfish_mmc_host *host = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%s\n", goldfish_mmc_cover_is_open(host) ? "open" :
+			"closed");
+}
+
+static DEVICE_ATTR(cover_switch, S_IRUGO, goldfish_mmc_show_cover_switch, NULL);
+
+static void
+goldfish_mmc_start_command(struct goldfish_mmc_host *host, struct mmc_command *cmd)
+{
+	u32 cmdreg;
+	u32 resptype;
+	u32 cmdtype;
+
+	host->cmd = cmd;
+
+	resptype = 0;
+	cmdtype = 0;
+
+	/* Our hardware needs to know exact type */
+	switch (mmc_resp_type(cmd)) {
+	case MMC_RSP_NONE:
+		break;
+	case MMC_RSP_R1:
+	case MMC_RSP_R1B:
+		/* resp 1, 1b, 6, 7 */
+		resptype = 1;
+		break;
+	case MMC_RSP_R2:
+		resptype = 2;
+		break;
+	case MMC_RSP_R3:
+		resptype = 3;
+		break;
+	default:
+		dev_err(mmc_dev(host->mmc), "Invalid response type: %04x\n", mmc_resp_type(cmd));
+		break;
+	}
+
+	if (mmc_cmd_type(cmd) == MMC_CMD_ADTC) {
+		cmdtype = OMAP_MMC_CMDTYPE_ADTC;
+	} else if (mmc_cmd_type(cmd) == MMC_CMD_BC) {
+		cmdtype = OMAP_MMC_CMDTYPE_BC;
+	} else if (mmc_cmd_type(cmd) == MMC_CMD_BCR) {
+		cmdtype = OMAP_MMC_CMDTYPE_BCR;
+	} else {
+		cmdtype = OMAP_MMC_CMDTYPE_AC;
+	}
+
+	cmdreg = cmd->opcode | (resptype << 8) | (cmdtype << 12);
+
+	if (host->bus_mode == MMC_BUSMODE_OPENDRAIN)
+		cmdreg |= 1 << 6;
+
+	if (cmd->flags & MMC_RSP_BUSY)
+		cmdreg |= 1 << 11;
+
+	if (host->data && !(host->data->flags & MMC_DATA_WRITE))
+		cmdreg |= 1 << 15;
+
+	GOLDFISH_MMC_WRITE(host, MMC_ARG, cmd->arg);
+	GOLDFISH_MMC_WRITE(host, MMC_CMD, cmdreg);
+}
+
+static void
+goldfish_mmc_xfer_done(struct goldfish_mmc_host *host, struct mmc_data *data)
+{
+	if (host->dma_in_use) {
+		enum dma_data_direction dma_data_dir;
+
+		if (data->flags & MMC_DATA_WRITE)
+			dma_data_dir = DMA_TO_DEVICE;
+		else
+			dma_data_dir = DMA_FROM_DEVICE;
+
+		if (dma_data_dir == DMA_FROM_DEVICE) {
+			// we don't really have DMA, so we need to copy from our platform driver buffer
+			uint8_t* dest = (uint8_t *)sg_virt(data->sg);
+			memcpy(dest, host->virt_base, data->sg->length);
+		}
+
+		host->data->bytes_xfered += data->sg->length;
+
+		dma_unmap_sg(mmc_dev(host->mmc), data->sg, host->sg_len, dma_data_dir);
+	}
+	
+	host->data = NULL;
+	host->sg_len = 0;
+
+	/* NOTE:  MMC layer will sometimes poll-wait CMD13 next, issuing
+	 * dozens of requests until the card finishes writing data.
+	 * It'd be cheaper to just wait till an EOFB interrupt arrives...
+	 */
+
+	if (!data->stop) {
+		host->mrq = NULL;
+		mmc_request_done(host->mmc, data->mrq);
+		return;
+	}
+
+	goldfish_mmc_start_command(host, data->stop);
+}
+
+static void
+goldfish_mmc_end_of_data(struct goldfish_mmc_host *host, struct mmc_data *data)
+{
+	if (!host->dma_in_use) {
+		goldfish_mmc_xfer_done(host, data);
+		return;
+	}
+	if (host->dma_done)
+		goldfish_mmc_xfer_done(host, data);
+}
+
+static void
+goldfish_mmc_cmd_done(struct goldfish_mmc_host *host, struct mmc_command *cmd)
+{
+	host->cmd = NULL;
+	if (cmd->flags & MMC_RSP_PRESENT) {
+		if (cmd->flags & MMC_RSP_136) {
+			/* response type 2 */
+			cmd->resp[3] =
+				GOLDFISH_MMC_READ(host, MMC_RESP_0);
+			cmd->resp[2] =
+				GOLDFISH_MMC_READ(host, MMC_RESP_1);
+			cmd->resp[1] =
+				GOLDFISH_MMC_READ(host, MMC_RESP_2);
+			cmd->resp[0] =
+				GOLDFISH_MMC_READ(host, MMC_RESP_3);
+		} else {
+			/* response types 1, 1b, 3, 4, 5, 6 */
+			cmd->resp[0] =
+				GOLDFISH_MMC_READ(host, MMC_RESP_0);
+		}
+	}
+
+	if (host->data == NULL || cmd->error) {
+		host->mrq = NULL;
+		mmc_request_done(host->mmc, cmd->mrq);
+	}
+}
+
+static irqreturn_t goldfish_mmc_irq(int irq, void *dev_id)
+{
+	struct goldfish_mmc_host * host = (struct goldfish_mmc_host *)dev_id;
+	u16 status;
+	int end_command;
+	int end_transfer;
+	int transfer_error;
+	int state_changed;
+
+	if (host->cmd == NULL && host->data == NULL) {
+		status = GOLDFISH_MMC_READ(host, MMC_INT_STATUS);
+		dev_info(mmc_dev(host->mmc),"spurious irq 0x%04x\n", status);
+		if (status != 0) {
+			GOLDFISH_MMC_WRITE(host, MMC_INT_STATUS, status);
+			GOLDFISH_MMC_WRITE(host, MMC_INT_ENABLE, 0);
+		}
+		return IRQ_HANDLED;
+	}
+
+	end_command = 0;
+	end_transfer = 0;
+	transfer_error = 0;
+	state_changed = 0;
+
+	while ((status = GOLDFISH_MMC_READ(host, MMC_INT_STATUS)) != 0) {
+		GOLDFISH_MMC_WRITE(host, MMC_INT_STATUS, status);
+
+		if (status & MMC_STAT_END_OF_CMD) {
+			end_command = 1;
+		}
+
+		if (status & MMC_STAT_END_OF_DATA) {
+			end_transfer = 1;
+		}
+		if (status & MMC_STAT_STATE_CHANGE) {
+			state_changed = 1;
+		}
+	}
+
+	if (end_command) {
+		goldfish_mmc_cmd_done(host, host->cmd);
+	}
+	if (transfer_error)
+		goldfish_mmc_xfer_done(host, host->data);
+	else if (end_transfer) {
+		host->dma_done = 1;
+		goldfish_mmc_end_of_data(host, host->data);
+	}
+	if (state_changed) {
+		schedule_work(&host->switch_work);
+	}
+
+	return IRQ_HANDLED;
+}
+
+
+static void goldfish_mmc_switch_handler(struct work_struct *work)
+{
+/*
+	struct goldfish_mmc_host *host = container_of(work, struct goldfish_mmc_host, switch_work);
+	struct mmc_card *card;
+	static int complained = 0;
+	int cards = 0, cover_open;
+
+	cover_open = goldfish_mmc_cover_is_open(host);
+	if (cover_open != host->switch_last_state) {
+		kobject_uevent(&host->dev->kobj, KOBJ_CHANGE);
+		host->switch_last_state = cover_open;
+	}
+	mmc_detect_change(host->mmc, 0);
+	list_for_each_entry(card, &host->mmc->cards, node) {
+		if (mmc_card_present(card))
+			cards++;
+	}
+	if (goldfish_mmc_cover_is_open(host)) {
+		if (!complained) {
+			dev_info(mmc_dev(host->mmc), "cover is open\n");
+			complained = 1;
+		}
+	} else {
+		complained = 0;
+	}
+*/
+}
+
+
+static void
+goldfish_mmc_prepare_data(struct goldfish_mmc_host *host, struct mmc_request *req)
+{
+	struct mmc_data *data = req->data;
+	int block_size;
+	unsigned sg_len;
+	enum dma_data_direction dma_data_dir;
+
+	host->data = data;
+	if (data == NULL) {
+		GOLDFISH_MMC_WRITE(host, MMC_BLOCK_LENGTH, 0);
+		GOLDFISH_MMC_WRITE(host, MMC_BLOCK_COUNT, 0);
+		host->dma_in_use = 0;
+		return;
+	}
+
+	block_size = data->blksz;
+
+	GOLDFISH_MMC_WRITE(host, MMC_BLOCK_COUNT, data->blocks - 1);
+	GOLDFISH_MMC_WRITE(host, MMC_BLOCK_LENGTH, block_size - 1);
+
+	/* cope with calling layer confusion; it issues "single
+	 * block" writes using multi-block scatterlists.
+	 */
+	sg_len = (data->blocks == 1) ? 1 : data->sg_len;
+
+	if (data->flags & MMC_DATA_WRITE)
+		dma_data_dir = DMA_TO_DEVICE;
+	else
+		dma_data_dir = DMA_FROM_DEVICE;
+
+	host->sg_len = dma_map_sg(mmc_dev(host->mmc), data->sg,
+				sg_len, dma_data_dir);
+	host->dma_done = 0;
+	host->dma_in_use = 1;
+	
+	if (dma_data_dir == DMA_TO_DEVICE) {
+		// we don't really have DMA, so we need to copy to our platform driver buffer
+		const uint8_t* src = (uint8_t *)sg_virt(data->sg);
+		memcpy(host->virt_base, src, data->sg->length);
+	}
+}
+
+static void goldfish_mmc_request(struct mmc_host *mmc, struct mmc_request *req)
+{
+	struct goldfish_mmc_host *host = mmc_priv(mmc);
+
+	WARN_ON(host->mrq != NULL);
+
+	host->mrq = req;
+	goldfish_mmc_prepare_data(host, req);
+	goldfish_mmc_start_command(host, req->cmd);
+
+	/* this is to avoid accidentally being detected as an SDIO card in mmc_attach_sdio() */
+	if (req->cmd->opcode == SD_IO_SEND_OP_COND &&
+		req->cmd->flags == (MMC_RSP_SPI_R4 | MMC_RSP_R4 | MMC_CMD_BCR)) {
+		req->cmd->error = -EINVAL;
+	}
+}
+
+static void goldfish_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
+{
+	struct goldfish_mmc_host *host = mmc_priv(mmc);
+
+	host->bus_mode = ios->bus_mode;
+	host->hw_bus_mode = host->bus_mode;
+}
+
+static int goldfish_mmc_get_ro(struct mmc_host *mmc)
+{
+	uint32_t state;
+	struct goldfish_mmc_host *host = mmc_priv(mmc);
+	
+	state = GOLDFISH_MMC_READ(host, MMC_STATE);
+	return ((state & MMC_STATE_READ_ONLY) != 0);
+}
+
+static const struct mmc_host_ops goldfish_mmc_ops = {
+	.request	= goldfish_mmc_request,
+	.set_ios	= goldfish_mmc_set_ios,
+	.get_ro		= goldfish_mmc_get_ro,
+};
+
+static int __init goldfish_mmc_probe(struct platform_device *pdev)
+{
+	struct mmc_host *mmc;
+	struct goldfish_mmc_host *host = NULL;
+	struct resource *res;
+	int ret = 0;
+	int irq;
+	dma_addr_t buf_addr;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	irq = platform_get_irq(pdev, 0);
+	if (res == NULL || irq < 0)
+		return -ENXIO;
+
+	mmc = mmc_alloc_host(sizeof(struct goldfish_mmc_host), &pdev->dev);
+	if (mmc == NULL) {
+		ret = -ENOMEM;
+		goto err_alloc_host_failed;
+	}
+
+	host = mmc_priv(mmc);
+	host->mmc = mmc;	
+	host->reg_base = IO_ADDRESS(res->start - IO_START);
+	host->virt_base = dma_alloc_writecombine(&pdev->dev, BUFFER_SIZE,
+												&buf_addr, GFP_KERNEL);
+	if(host->virt_base == 0) {
+		ret = -EBUSY;
+		goto dma_alloc_failed;
+	}
+	host->phys_base = buf_addr;
+
+	host->id = pdev->id;
+	host->irq = irq;
+
+	mmc->ops = &goldfish_mmc_ops;
+	mmc->f_min = 400000;
+	mmc->f_max = 24000000;
+	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
+	mmc->caps = MMC_CAP_4_BIT_DATA;
+
+	/* Use scatterlist DMA to reduce per-transfer costs.
+	 * NOTE max_seg_size assumption that small blocks aren't
+	 * normally used (except e.g. for reading SD registers).
+	 */
+	mmc->max_phys_segs = 32;
+	mmc->max_hw_segs = 32;
+	mmc->max_blk_size = 2048;	/* MMC_BLOCK_LENGTH is 11 bits (+1) */
+	mmc->max_blk_count = 2048;	/* MMC_BLOCK_COUNT is 11 bits (+1) */
+	mmc->max_req_size = BUFFER_SIZE;
+	mmc->max_seg_size = mmc->max_req_size;
+
+	ret = request_irq(host->irq, goldfish_mmc_irq, 0, DRIVER_NAME, host);
+	if (ret)
+		goto err_request_irq_failed;
+
+	host->dev = &pdev->dev;
+	platform_set_drvdata(pdev, host);
+
+	ret = device_create_file(&pdev->dev, &dev_attr_cover_switch);
+	if (ret)
+		dev_warn(mmc_dev(host->mmc), "Unable to create sysfs attributes\n");
+
+	mmc_add_host(mmc);
+
+	GOLDFISH_MMC_WRITE(host, MMC_SET_BUFFER, host->phys_base);	
+	GOLDFISH_MMC_WRITE(host, MMC_INT_ENABLE, 
+			MMC_STAT_END_OF_CMD | MMC_STAT_END_OF_DATA | MMC_STAT_STATE_CHANGE 
+			);
+
+	// we start with the card present
+	kobject_uevent(&host->dev->kobj, KOBJ_CHANGE);
+	mmc_detect_change(host->mmc, 0);
+
+	INIT_WORK(&host->switch_work, goldfish_mmc_switch_handler);
+
+	return 0;
+
+err_request_irq_failed:
+	dma_free_writecombine(&pdev->dev, BUFFER_SIZE, host->virt_base, host->phys_base);
+dma_alloc_failed:
+	mmc_free_host(host->mmc);
+err_alloc_host_failed:
+	return ret;
+}
+
+static int goldfish_mmc_remove(struct platform_device *pdev)
+{
+	struct goldfish_mmc_host *host = platform_get_drvdata(pdev);
+
+	platform_set_drvdata(pdev, NULL);
+
+	BUG_ON(host == NULL);
+
+	mmc_remove_host(host->mmc);
+	free_irq(host->irq, host);
+	dma_free_writecombine(&pdev->dev, BUFFER_SIZE, host->virt_base, host->phys_base);
+	mmc_free_host(host->mmc);
+
+	return 0;
+}
+
+static struct platform_driver goldfish_mmc_driver = {
+	.probe		= goldfish_mmc_probe,
+	.remove		= goldfish_mmc_remove,
+	.driver		= {
+		.name	= DRIVER_NAME,
+	},
+};
+
+static int __init goldfish_mmc_init(void)
+{
+	return platform_driver_register(&goldfish_mmc_driver);
+}
+
+static void __exit goldfish_mmc_exit(void)
+{
+	platform_driver_unregister(&goldfish_mmc_driver);
+}
+
+module_init(goldfish_mmc_init);
+module_exit(goldfish_mmc_exit);
+