This commit was manufactured by cvs2svn to create branch 'vserver'.
[linux-2.6.git] / drivers / mmc / omap.c
diff --git a/drivers/mmc/omap.c b/drivers/mmc/omap.c
new file mode 100644 (file)
index 0000000..becb3c6
--- /dev/null
@@ -0,0 +1,1226 @@
+/*
+ *  linux/drivers/media/mmc/omap.c
+ *
+ *  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/config.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/dma-mapping.h>
+#include <linux/delay.h>
+#include <linux/spinlock.h>
+#include <linux/timer.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/protocol.h>
+#include <linux/mmc/card.h>
+#include <linux/clk.h>
+
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/scatterlist.h>
+#include <asm/mach-types.h>
+
+#include <asm/arch/board.h>
+#include <asm/arch/gpio.h>
+#include <asm/arch/dma.h>
+#include <asm/arch/mux.h>
+#include <asm/arch/fpga.h>
+#include <asm/arch/tps65010.h>
+
+#include "omap.h"
+
+#define DRIVER_NAME "mmci-omap"
+#define RSP_TYPE(x)    ((x) & ~(MMC_RSP_BUSY|MMC_RSP_OPCODE))
+
+/* Specifies how often in millisecs to poll for card status changes
+ * when the cover switch is open */
+#define OMAP_MMC_SWITCH_POLL_DELAY     500
+
+static int mmc_omap_enable_poll = 1;
+
+struct mmc_omap_host {
+       int                     initialized;
+       int                     suspended;
+       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 */
+       struct clk *            iclk;
+       struct clk *            fclk;
+       void __iomem            *base;
+       int                     irq;
+       unsigned char           bus_mode;
+       unsigned char           hw_bus_mode;
+
+       unsigned int            sg_len;
+       int                     sg_idx;
+       u16 *                   buffer;
+       u32                     buffer_bytes_left;
+       u32                     total_bytes_left;
+
+       unsigned                use_dma:1;
+       unsigned                brs_received:1, dma_done:1;
+       unsigned                dma_is_read:1;
+       unsigned                dma_in_use:1;
+       int                     dma_ch;
+       spinlock_t              dma_lock;
+       struct timer_list       dma_timer;
+       unsigned                dma_len;
+
+       short                   power_pin;
+       short                   wp_pin;
+
+       int                     switch_pin;
+       struct work_struct      switch_work;
+       struct timer_list       switch_timer;
+       int                     switch_last_state;
+};
+
+static inline int
+mmc_omap_cover_is_open(struct mmc_omap_host *host)
+{
+       if (host->switch_pin < 0)
+               return 0;
+       return omap_get_gpio_datain(host->switch_pin);
+}
+
+static ssize_t
+mmc_omap_show_cover_switch(struct device *dev,
+       struct device_attribute *attr, char *buf)
+{
+       struct mmc_omap_host *host = dev_get_drvdata(dev);
+
+       return sprintf(buf, "%s\n", mmc_omap_cover_is_open(host) ? "open" :
+                       "closed");
+}
+
+static DEVICE_ATTR(cover_switch, S_IRUGO, mmc_omap_show_cover_switch, NULL);
+
+static ssize_t
+mmc_omap_show_enable_poll(struct device *dev,
+       struct device_attribute *attr, char *buf)
+{
+       return snprintf(buf, PAGE_SIZE, "%d\n", mmc_omap_enable_poll);
+}
+
+static ssize_t
+mmc_omap_store_enable_poll(struct device *dev,
+       struct device_attribute *attr, const char *buf,
+       size_t size)
+{
+       int enable_poll;
+
+       if (sscanf(buf, "%10d", &enable_poll) != 1)
+               return -EINVAL;
+
+       if (enable_poll != mmc_omap_enable_poll) {
+               struct mmc_omap_host *host = dev_get_drvdata(dev);
+
+               mmc_omap_enable_poll = enable_poll;
+               if (enable_poll && host->switch_pin >= 0)
+                       schedule_work(&host->switch_work);
+       }
+       return size;
+}
+
+static DEVICE_ATTR(enable_poll, 0664,
+                  mmc_omap_show_enable_poll, mmc_omap_store_enable_poll);
+
+static void
+mmc_omap_start_command(struct mmc_omap_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 (RSP_TYPE(mmc_resp_type(cmd))) {
+       case RSP_TYPE(MMC_RSP_R1):
+               /* resp 1, resp 1b */
+               resptype = 1;
+               break;
+       case RSP_TYPE(MMC_RSP_R2):
+               resptype = 2;
+               break;
+       case RSP_TYPE(MMC_RSP_R3):
+               resptype = 3;
+               break;
+       default:
+               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;
+
+       clk_enable(host->fclk);
+
+       OMAP_MMC_WRITE(host->base, CTO, 200);
+       OMAP_MMC_WRITE(host->base, ARGL, cmd->arg & 0xffff);
+       OMAP_MMC_WRITE(host->base, ARGH, cmd->arg >> 16);
+       OMAP_MMC_WRITE(host->base, IE,
+                      OMAP_MMC_STAT_A_EMPTY    | OMAP_MMC_STAT_A_FULL    |
+                      OMAP_MMC_STAT_CMD_CRC    | OMAP_MMC_STAT_CMD_TOUT  |
+                      OMAP_MMC_STAT_DATA_CRC   | OMAP_MMC_STAT_DATA_TOUT |
+                      OMAP_MMC_STAT_END_OF_CMD | OMAP_MMC_STAT_CARD_ERR  |
+                      OMAP_MMC_STAT_END_OF_DATA);
+       OMAP_MMC_WRITE(host->base, CMD, cmdreg);
+}
+
+static void
+mmc_omap_xfer_done(struct mmc_omap_host *host, struct mmc_data *data)
+{
+       if (host->dma_in_use) {
+               enum dma_data_direction dma_data_dir;
+
+               BUG_ON(host->dma_ch < 0);
+               if (data->error != MMC_ERR_NONE)
+                       omap_stop_dma(host->dma_ch);
+               /* Release DMA channel lazily */
+               mod_timer(&host->dma_timer, jiffies + HZ);
+               if (data->flags & MMC_DATA_WRITE)
+                       dma_data_dir = DMA_TO_DEVICE;
+               else
+                       dma_data_dir = DMA_FROM_DEVICE;
+               dma_unmap_sg(mmc_dev(host->mmc), data->sg, host->sg_len,
+                            dma_data_dir);
+       }
+       host->data = NULL;
+       host->sg_len = 0;
+       clk_disable(host->fclk);
+
+       /* 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;
+       }
+
+       mmc_omap_start_command(host, data->stop);
+}
+
+static void
+mmc_omap_end_of_data(struct mmc_omap_host *host, struct mmc_data *data)
+{
+       unsigned long flags;
+       int done;
+
+       if (!host->dma_in_use) {
+               mmc_omap_xfer_done(host, data);
+               return;
+       }
+       done = 0;
+       spin_lock_irqsave(&host->dma_lock, flags);
+       if (host->dma_done)
+               done = 1;
+       else
+               host->brs_received = 1;
+       spin_unlock_irqrestore(&host->dma_lock, flags);
+       if (done)
+               mmc_omap_xfer_done(host, data);
+}
+
+static void
+mmc_omap_dma_timer(unsigned long data)
+{
+       struct mmc_omap_host *host = (struct mmc_omap_host *) data;
+
+       BUG_ON(host->dma_ch < 0);
+       omap_free_dma(host->dma_ch);
+       host->dma_ch = -1;
+}
+
+static void
+mmc_omap_dma_done(struct mmc_omap_host *host, struct mmc_data *data)
+{
+       unsigned long flags;
+       int done;
+
+       done = 0;
+       spin_lock_irqsave(&host->dma_lock, flags);
+       if (host->brs_received)
+               done = 1;
+       else
+               host->dma_done = 1;
+       spin_unlock_irqrestore(&host->dma_lock, flags);
+       if (done)
+               mmc_omap_xfer_done(host, data);
+}
+
+static void
+mmc_omap_cmd_done(struct mmc_omap_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] =
+                               OMAP_MMC_READ(host->base, RSP0) |
+                               (OMAP_MMC_READ(host->base, RSP1) << 16);
+                       cmd->resp[2] =
+                               OMAP_MMC_READ(host->base, RSP2) |
+                               (OMAP_MMC_READ(host->base, RSP3) << 16);
+                       cmd->resp[1] =
+                               OMAP_MMC_READ(host->base, RSP4) |
+                               (OMAP_MMC_READ(host->base, RSP5) << 16);
+                       cmd->resp[0] =
+                               OMAP_MMC_READ(host->base, RSP6) |
+                               (OMAP_MMC_READ(host->base, RSP7) << 16);
+               } else {
+                       /* response types 1, 1b, 3, 4, 5, 6 */
+                       cmd->resp[0] =
+                               OMAP_MMC_READ(host->base, RSP6) |
+                               (OMAP_MMC_READ(host->base, RSP7) << 16);
+               }
+       }
+
+       if (host->data == NULL || cmd->error != MMC_ERR_NONE) {
+               host->mrq = NULL;
+               clk_disable(host->fclk);
+               mmc_request_done(host->mmc, cmd->mrq);
+       }
+}
+
+/* PIO only */
+static void
+mmc_omap_sg_to_buf(struct mmc_omap_host *host)
+{
+       struct scatterlist *sg;
+
+       sg = host->data->sg + host->sg_idx;
+       host->buffer_bytes_left = sg->length;
+       host->buffer = page_address(sg->page) + sg->offset;
+       if (host->buffer_bytes_left > host->total_bytes_left)
+               host->buffer_bytes_left = host->total_bytes_left;
+}
+
+/* PIO only */
+static void
+mmc_omap_xfer_data(struct mmc_omap_host *host, int write)
+{
+       int n;
+       void __iomem *reg;
+       u16 *p;
+
+       if (host->buffer_bytes_left == 0) {
+               host->sg_idx++;
+               BUG_ON(host->sg_idx == host->sg_len);
+               mmc_omap_sg_to_buf(host);
+       }
+       n = 64;
+       if (n > host->buffer_bytes_left)
+               n = host->buffer_bytes_left;
+       host->buffer_bytes_left -= n;
+       host->total_bytes_left -= n;
+       host->data->bytes_xfered += n;
+
+       if (write) {
+               __raw_writesw(host->base + OMAP_MMC_REG_DATA, host->buffer, n);
+       } else {
+               __raw_readsw(host->base + OMAP_MMC_REG_DATA, host->buffer, n);
+       }
+}
+
+static inline void mmc_omap_report_irq(u16 status)
+{
+       static const char *mmc_omap_status_bits[] = {
+               "EOC", "CD", "CB", "BRS", "EOFB", "DTO", "DCRC", "CTO",
+               "CCRC", "CRW", "AF", "AE", "OCRB", "CIRQ", "CERR"
+       };
+       int i, c = 0;
+
+       for (i = 0; i < ARRAY_SIZE(mmc_omap_status_bits); i++)
+               if (status & (1 << i)) {
+                       if (c)
+                               printk(" ");
+                       printk("%s", mmc_omap_status_bits[i]);
+                       c++;
+               }
+}
+
+static irqreturn_t mmc_omap_irq(int irq, void *dev_id, struct pt_regs *regs)
+{
+       struct mmc_omap_host * host = (struct mmc_omap_host *)dev_id;
+       u16 status;
+       int end_command;
+       int end_transfer;
+       int transfer_error;
+
+       if (host->cmd == NULL && host->data == NULL) {
+               status = OMAP_MMC_READ(host->base, STAT);
+               dev_info(mmc_dev(host->mmc),"spurious irq 0x%04x\n", status);
+               if (status != 0) {
+                       OMAP_MMC_WRITE(host->base, STAT, status);
+                       OMAP_MMC_WRITE(host->base, IE, 0);
+               }
+               return IRQ_HANDLED;
+       }
+
+       end_command = 0;
+       end_transfer = 0;
+       transfer_error = 0;
+
+       while ((status = OMAP_MMC_READ(host->base, STAT)) != 0) {
+               OMAP_MMC_WRITE(host->base, STAT, status);
+#ifdef CONFIG_MMC_DEBUG
+               dev_dbg(mmc_dev(host->mmc), "MMC IRQ %04x (CMD %d): ",
+                       status, host->cmd != NULL ? host->cmd->opcode : -1);
+               mmc_omap_report_irq(status);
+               printk("\n");
+#endif
+               if (host->total_bytes_left) {
+                       if ((status & OMAP_MMC_STAT_A_FULL) ||
+                           (status & OMAP_MMC_STAT_END_OF_DATA))
+                               mmc_omap_xfer_data(host, 0);
+                       if (status & OMAP_MMC_STAT_A_EMPTY)
+                               mmc_omap_xfer_data(host, 1);
+               }
+
+               if (status & OMAP_MMC_STAT_END_OF_DATA) {
+                       end_transfer = 1;
+               }
+
+               if (status & OMAP_MMC_STAT_DATA_TOUT) {
+                       dev_dbg(mmc_dev(host->mmc), "data timeout\n");
+                       if (host->data) {
+                               host->data->error |= MMC_ERR_TIMEOUT;
+                               transfer_error = 1;
+                       }
+               }
+
+               if (status & OMAP_MMC_STAT_DATA_CRC) {
+                       if (host->data) {
+                               host->data->error |= MMC_ERR_BADCRC;
+                               dev_dbg(mmc_dev(host->mmc),
+                                        "data CRC error, bytes left %d\n",
+                                       host->total_bytes_left);
+                               transfer_error = 1;
+                       } else {
+                               dev_dbg(mmc_dev(host->mmc), "data CRC error\n");
+                       }
+               }
+
+               if (status & OMAP_MMC_STAT_CMD_TOUT) {
+                       /* Timeouts are routine with some commands */
+                       if (host->cmd) {
+                               if (host->cmd->opcode != MMC_ALL_SEND_CID &&
+                                               host->cmd->opcode !=
+                                               MMC_SEND_OP_COND &&
+                                               host->cmd->opcode !=
+                                               MMC_APP_CMD &&
+                                               !mmc_omap_cover_is_open(host))
+                                       dev_err(mmc_dev(host->mmc),
+                                               "command timeout, CMD %d\n",
+                                               host->cmd->opcode);
+                               host->cmd->error = MMC_ERR_TIMEOUT;
+                               end_command = 1;
+                       }
+               }
+
+               if (status & OMAP_MMC_STAT_CMD_CRC) {
+                       if (host->cmd) {
+                               dev_err(mmc_dev(host->mmc),
+                                       "command CRC error (CMD%d, arg 0x%08x)\n",
+                                       host->cmd->opcode, host->cmd->arg);
+                               host->cmd->error = MMC_ERR_BADCRC;
+                               end_command = 1;
+                       } else
+                               dev_err(mmc_dev(host->mmc),
+                                       "command CRC error without cmd?\n");
+               }
+
+               if (status & OMAP_MMC_STAT_CARD_ERR) {
+                       if (host->cmd && host->cmd->opcode == MMC_STOP_TRANSMISSION) {
+                               u32 response = OMAP_MMC_READ(host->base, RSP6)
+                                       | (OMAP_MMC_READ(host->base, RSP7) << 16);
+                               /* STOP sometimes sets must-ignore bits */
+                               if (!(response & (R1_CC_ERROR
+                                                               | R1_ILLEGAL_COMMAND
+                                                               | R1_COM_CRC_ERROR))) {
+                                       end_command = 1;
+                                       continue;
+                               }
+                       }
+
+                       dev_dbg(mmc_dev(host->mmc), "card status error (CMD%d)\n",
+                               host->cmd->opcode);
+                       if (host->cmd) {
+                               host->cmd->error = MMC_ERR_FAILED;
+                               end_command = 1;
+                       }
+                       if (host->data) {
+                               host->data->error = MMC_ERR_FAILED;
+                               transfer_error = 1;
+                       }
+               }
+
+               /*
+                * NOTE: On 1610 the END_OF_CMD may come too early when
+                * starting a write 
+                */
+               if ((status & OMAP_MMC_STAT_END_OF_CMD) &&
+                   (!(status & OMAP_MMC_STAT_A_EMPTY))) {
+                       end_command = 1;
+               }
+       }
+
+       if (end_command) {
+               mmc_omap_cmd_done(host, host->cmd);
+       }
+       if (transfer_error)
+               mmc_omap_xfer_done(host, host->data);
+       else if (end_transfer)
+               mmc_omap_end_of_data(host, host->data);
+
+       return IRQ_HANDLED;
+}
+
+static irqreturn_t mmc_omap_switch_irq(int irq, void *dev_id, struct pt_regs *regs)
+{
+       struct mmc_omap_host *host = (struct mmc_omap_host *) dev_id;
+
+       schedule_work(&host->switch_work);
+
+       return IRQ_HANDLED;
+}
+
+static void mmc_omap_switch_timer(unsigned long arg)
+{
+       struct mmc_omap_host *host = (struct mmc_omap_host *) arg;
+
+       schedule_work(&host->switch_work);
+}
+
+/* FIXME: Handle card insertion and removal properly. Maybe use a mask
+ * for MMC state? */
+static void mmc_omap_switch_callback(unsigned long data, u8 mmc_mask)
+{
+}
+
+static void mmc_omap_switch_handler(void *data)
+{
+       struct mmc_omap_host *host = (struct mmc_omap_host *) data;
+       struct mmc_card *card;
+       static int complained = 0;
+       int cards = 0, cover_open;
+
+       if (host->switch_pin == -1)
+               return;
+       cover_open = mmc_omap_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 (mmc_omap_cover_is_open(host)) {
+               if (!complained) {
+                       dev_info(mmc_dev(host->mmc), "cover is open");
+                       complained = 1;
+               }
+               if (mmc_omap_enable_poll)
+                       mod_timer(&host->switch_timer, jiffies +
+                               msecs_to_jiffies(OMAP_MMC_SWITCH_POLL_DELAY));
+       } else {
+               complained = 0;
+       }
+}
+
+/* Prepare to transfer the next segment of a scatterlist */
+static void
+mmc_omap_prepare_dma(struct mmc_omap_host *host, struct mmc_data *data)
+{
+       int dma_ch = host->dma_ch;
+       unsigned long data_addr;
+       u16 buf, frame;
+       u32 count;
+       struct scatterlist *sg = &data->sg[host->sg_idx];
+       int src_port = 0;
+       int dst_port = 0;
+       int sync_dev = 0;
+
+       data_addr = io_v2p((u32) host->base) + OMAP_MMC_REG_DATA;
+       frame = 1 << data->blksz_bits;
+       count = sg_dma_len(sg);
+
+       if ((data->blocks == 1) && (count > (1 << data->blksz_bits)))
+               count = frame;
+
+       host->dma_len = count;
+
+       /* FIFO is 16x2 bytes on 15xx, and 32x2 bytes on 16xx and 24xx.
+        * Use 16 or 32 word frames when the blocksize is at least that large.
+        * Blocksize is usually 512 bytes; but not for some SD reads.
+        */
+       if (cpu_is_omap15xx() && frame > 32)
+               frame = 32;
+       else if (frame > 64)
+               frame = 64;
+       count /= frame;
+       frame >>= 1;
+
+       if (!(data->flags & MMC_DATA_WRITE)) {
+               buf = 0x800f | ((frame - 1) << 8);
+
+               if (cpu_class_is_omap1()) {
+                       src_port = OMAP_DMA_PORT_TIPB;
+                       dst_port = OMAP_DMA_PORT_EMIFF;
+               }
+               if (cpu_is_omap24xx())
+                       sync_dev = OMAP24XX_DMA_MMC1_RX;
+
+               omap_set_dma_src_params(dma_ch, src_port,
+                                       OMAP_DMA_AMODE_CONSTANT,
+                                       data_addr, 0, 0);
+               omap_set_dma_dest_params(dma_ch, dst_port,
+                                        OMAP_DMA_AMODE_POST_INC,
+                                        sg_dma_address(sg), 0, 0);
+               omap_set_dma_dest_data_pack(dma_ch, 1);
+               omap_set_dma_dest_burst_mode(dma_ch, OMAP_DMA_DATA_BURST_4);
+       } else {
+               buf = 0x0f80 | ((frame - 1) << 0);
+
+               if (cpu_class_is_omap1()) {
+                       src_port = OMAP_DMA_PORT_EMIFF;
+                       dst_port = OMAP_DMA_PORT_TIPB;
+               }
+               if (cpu_is_omap24xx())
+                       sync_dev = OMAP24XX_DMA_MMC1_TX;
+
+               omap_set_dma_dest_params(dma_ch, dst_port,
+                                        OMAP_DMA_AMODE_CONSTANT,
+                                        data_addr, 0, 0);
+               omap_set_dma_src_params(dma_ch, src_port,
+                                       OMAP_DMA_AMODE_POST_INC,
+                                       sg_dma_address(sg), 0, 0);
+               omap_set_dma_src_data_pack(dma_ch, 1);
+               omap_set_dma_src_burst_mode(dma_ch, OMAP_DMA_DATA_BURST_4);
+       }
+
+       /* Max limit for DMA frame count is 0xffff */
+       if (unlikely(count > 0xffff))
+               BUG();
+
+       OMAP_MMC_WRITE(host->base, BUF, buf);
+       omap_set_dma_transfer_params(dma_ch, OMAP_DMA_DATA_TYPE_S16,
+                                    frame, count, OMAP_DMA_SYNC_FRAME,
+                                    sync_dev, 0);
+}
+
+/* A scatterlist segment completed */
+static void mmc_omap_dma_cb(int lch, u16 ch_status, void *data)
+{
+       struct mmc_omap_host *host = (struct mmc_omap_host *) data;
+       struct mmc_data *mmcdat = host->data;
+
+       if (unlikely(host->dma_ch < 0)) {
+               dev_err(mmc_dev(host->mmc), "DMA callback while DMA not
+                               enabled\n");
+               return;
+       }
+       /* FIXME: We really should do something to _handle_ the errors */
+       if (ch_status & OMAP_DMA_TOUT_IRQ) {
+               dev_err(mmc_dev(host->mmc),"DMA timeout\n");
+               return;
+       }
+       if (ch_status & OMAP_DMA_DROP_IRQ) {
+               dev_err(mmc_dev(host->mmc), "DMA sync error\n");
+               return;
+       }
+       if (!(ch_status & OMAP_DMA_BLOCK_IRQ)) {
+               return;
+       }
+       mmcdat->bytes_xfered += host->dma_len;
+       host->sg_idx++;
+       if (host->sg_idx < host->sg_len) {
+               mmc_omap_prepare_dma(host, host->data);
+               omap_start_dma(host->dma_ch);
+       } else
+               mmc_omap_dma_done(host, host->data);
+}
+
+static int mmc_omap_get_dma_channel(struct mmc_omap_host *host, struct mmc_data *data)
+{
+       const char *dev_name;
+       int sync_dev, dma_ch, is_read, r;
+
+       is_read = !(data->flags & MMC_DATA_WRITE);
+       del_timer_sync(&host->dma_timer);
+       if (host->dma_ch >= 0) {
+               if (is_read == host->dma_is_read)
+                       return 0;
+               omap_free_dma(host->dma_ch);
+               host->dma_ch = -1;
+       }
+
+       if (is_read) {
+               if (host->id == 1) {
+                       sync_dev = OMAP_DMA_MMC_RX;
+                       dev_name = "MMC1 read";
+               } else {
+                       sync_dev = OMAP_DMA_MMC2_RX;
+                       dev_name = "MMC2 read";
+               }
+       } else {
+               if (host->id == 1) {
+                       sync_dev = OMAP_DMA_MMC_TX;
+                       dev_name = "MMC1 write";
+               } else {
+                       sync_dev = OMAP_DMA_MMC2_TX;
+                       dev_name = "MMC2 write";
+               }
+       }
+       r = omap_request_dma(sync_dev, dev_name, mmc_omap_dma_cb,
+                            host, &dma_ch);
+       if (r != 0) {
+               dev_dbg(mmc_dev(host->mmc), "omap_request_dma() failed with %d\n", r);
+               return r;
+       }
+       host->dma_ch = dma_ch;
+       host->dma_is_read = is_read;
+
+       return 0;
+}
+
+static inline void set_cmd_timeout(struct mmc_omap_host *host, struct mmc_request *req)
+{
+       u16 reg;
+
+       reg = OMAP_MMC_READ(host->base, SDIO);
+       reg &= ~(1 << 5);
+       OMAP_MMC_WRITE(host->base, SDIO, reg);
+       /* Set maximum timeout */
+       OMAP_MMC_WRITE(host->base, CTO, 0xff);
+}
+
+static inline void set_data_timeout(struct mmc_omap_host *host, struct mmc_request *req)
+{
+       int timeout;
+       u16 reg;
+
+       /* Convert ns to clock cycles by assuming 20MHz frequency
+        * 1 cycle at 20MHz = 500 ns
+        */
+       timeout = req->data->timeout_clks + req->data->timeout_ns / 500;
+
+       /* Check if we need to use timeout multiplier register */
+       reg = OMAP_MMC_READ(host->base, SDIO);
+       if (timeout > 0xffff) {
+               reg |= (1 << 5);
+               timeout /= 1024;
+       } else
+               reg &= ~(1 << 5);
+       OMAP_MMC_WRITE(host->base, SDIO, reg);
+       OMAP_MMC_WRITE(host->base, DTO, timeout);
+}
+
+static void
+mmc_omap_prepare_data(struct mmc_omap_host *host, struct mmc_request *req)
+{
+       struct mmc_data *data = req->data;
+       int i, use_dma, block_size;
+       unsigned sg_len;
+
+       host->data = data;
+       if (data == NULL) {
+               OMAP_MMC_WRITE(host->base, BLEN, 0);
+               OMAP_MMC_WRITE(host->base, NBLK, 0);
+               OMAP_MMC_WRITE(host->base, BUF, 0);
+               host->dma_in_use = 0;
+               set_cmd_timeout(host, req);
+               return;
+       }
+
+
+       block_size = 1 << data->blksz_bits;
+
+       OMAP_MMC_WRITE(host->base, NBLK, data->blocks - 1);
+       OMAP_MMC_WRITE(host->base, BLEN, block_size - 1);
+       set_data_timeout(host, req);
+
+       /* cope with calling layer confusion; it issues "single
+        * block" writes using multi-block scatterlists.
+        */
+       sg_len = (data->blocks == 1) ? 1 : data->sg_len;
+
+       /* Only do DMA for entire blocks */
+       use_dma = host->use_dma;
+       if (use_dma) {
+               for (i = 0; i < sg_len; i++) {
+                       if ((data->sg[i].length % block_size) != 0) {
+                               use_dma = 0;
+                               break;
+                       }
+               }
+       }
+
+       host->sg_idx = 0;
+       if (use_dma) {
+               if (mmc_omap_get_dma_channel(host, data) == 0) {
+                       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;
+
+                       host->sg_len = dma_map_sg(mmc_dev(host->mmc), data->sg,
+                                               sg_len, dma_data_dir);
+                       host->total_bytes_left = 0;
+                       mmc_omap_prepare_dma(host, req->data);
+                       host->brs_received = 0;
+                       host->dma_done = 0;
+                       host->dma_in_use = 1;
+               } else
+                       use_dma = 0;
+       }
+
+       /* Revert to PIO? */
+       if (!use_dma) {
+               OMAP_MMC_WRITE(host->base, BUF, 0x1f1f);
+               host->total_bytes_left = data->blocks * block_size;
+               host->sg_len = sg_len;
+               mmc_omap_sg_to_buf(host);
+               host->dma_in_use = 0;
+       }
+}
+
+static void mmc_omap_request(struct mmc_host *mmc, struct mmc_request *req)
+{
+       struct mmc_omap_host *host = mmc_priv(mmc);
+
+       WARN_ON(host->mrq != NULL);
+
+       host->mrq = req;
+
+       /* only touch fifo AFTER the controller readies it */
+       mmc_omap_prepare_data(host, req);
+       mmc_omap_start_command(host, req->cmd);
+       if (host->dma_in_use)
+               omap_start_dma(host->dma_ch);
+}
+
+static void innovator_fpga_socket_power(int on)
+{
+#if defined(CONFIG_MACH_OMAP_INNOVATOR) && defined(CONFIG_ARCH_OMAP15XX)
+
+       if (on) {
+               fpga_write(fpga_read(OMAP1510_FPGA_POWER) | (1 << 3),
+                    OMAP1510_FPGA_POWER);
+       } else {
+               fpga_write(fpga_read(OMAP1510_FPGA_POWER) & ~(1 << 3),
+                    OMAP1510_FPGA_POWER);
+       }
+#endif
+}
+
+/*
+ * Turn the socket power on/off. Innovator uses FPGA, most boards
+ * probably use GPIO.
+ */
+static void mmc_omap_power(struct mmc_omap_host *host, int on)
+{
+       if (on) {
+               if (machine_is_omap_innovator())
+                       innovator_fpga_socket_power(1);
+               else if (machine_is_omap_h2())
+                       tps65010_set_gpio_out_value(GPIO3, HIGH);
+               else if (machine_is_omap_h3())
+                       /* GPIO 4 of TPS65010 sends SD_EN signal */
+                       tps65010_set_gpio_out_value(GPIO4, HIGH);
+               else if (cpu_is_omap24xx()) {
+                       u16 reg = OMAP_MMC_READ(host->base, CON);
+                       OMAP_MMC_WRITE(host->base, CON, reg | (1 << 11));
+               } else
+                       if (host->power_pin >= 0)
+                               omap_set_gpio_dataout(host->power_pin, 1);
+       } else {
+               if (machine_is_omap_innovator())
+                       innovator_fpga_socket_power(0);
+               else if (machine_is_omap_h2())
+                       tps65010_set_gpio_out_value(GPIO3, LOW);
+               else if (machine_is_omap_h3())
+                       tps65010_set_gpio_out_value(GPIO4, LOW);
+               else if (cpu_is_omap24xx()) {
+                       u16 reg = OMAP_MMC_READ(host->base, CON);
+                       OMAP_MMC_WRITE(host->base, CON, reg & ~(1 << 11));
+               } else
+                       if (host->power_pin >= 0)
+                               omap_set_gpio_dataout(host->power_pin, 0);
+       }
+}
+
+static void mmc_omap_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
+{
+       struct mmc_omap_host *host = mmc_priv(mmc);
+       int dsor;
+       int realclock, i;
+
+       realclock = ios->clock;
+
+       if (ios->clock == 0)
+               dsor = 0;
+       else {
+               int func_clk_rate = clk_get_rate(host->fclk);
+
+               dsor = func_clk_rate / realclock;
+               if (dsor < 1)
+                       dsor = 1;
+
+               if (func_clk_rate / dsor > realclock)
+                       dsor++;
+
+               if (dsor > 250)
+                       dsor = 250;
+               dsor++;
+
+               if (ios->bus_width == MMC_BUS_WIDTH_4)
+                       dsor |= 1 << 15;
+       }
+
+       switch (ios->power_mode) {
+       case MMC_POWER_OFF:
+               mmc_omap_power(host, 0);
+               break;
+       case MMC_POWER_UP:
+       case MMC_POWER_ON:
+               mmc_omap_power(host, 1);
+               dsor |= 1<<11;
+               break;
+       }
+
+       host->bus_mode = ios->bus_mode;
+       host->hw_bus_mode = host->bus_mode;
+
+       clk_enable(host->fclk);
+
+       /* On insanely high arm_per frequencies something sometimes
+        * goes somehow out of sync, and the POW bit is not being set,
+        * which results in the while loop below getting stuck.
+        * Writing to the CON register twice seems to do the trick. */
+       for (i = 0; i < 2; i++)
+               OMAP_MMC_WRITE(host->base, CON, dsor);
+       if (ios->power_mode == MMC_POWER_UP) {
+               /* Send clock cycles, poll completion */
+               OMAP_MMC_WRITE(host->base, IE, 0);
+               OMAP_MMC_WRITE(host->base, STAT, 0xffff);
+               OMAP_MMC_WRITE(host->base, CMD, 1<<7);
+               while (0 == (OMAP_MMC_READ(host->base, STAT) & 1));
+               OMAP_MMC_WRITE(host->base, STAT, 1);
+       }
+       clk_disable(host->fclk);
+}
+
+static int mmc_omap_get_ro(struct mmc_host *mmc)
+{
+       struct mmc_omap_host *host = mmc_priv(mmc);
+
+       return host->wp_pin && omap_get_gpio_datain(host->wp_pin);
+}
+
+static struct mmc_host_ops mmc_omap_ops = {
+       .request        = mmc_omap_request,
+       .set_ios        = mmc_omap_set_ios,
+       .get_ro         = mmc_omap_get_ro,
+};
+
+static int __init mmc_omap_probe(struct platform_device *pdev)
+{
+       struct omap_mmc_conf *minfo = pdev->dev.platform_data;
+       struct mmc_host *mmc;
+       struct mmc_omap_host *host = NULL;
+       int ret = 0;
+       
+       if (platform_get_resource(pdev, IORESOURCE_MEM, 0) ||
+                       platform_get_irq(pdev, IORESOURCE_IRQ, 0)) {
+               dev_err(&pdev->dev, "mmc_omap_probe: invalid resource type\n");
+               return -ENODEV;
+       }
+
+       if (!request_mem_region(pdev->resource[0].start,
+                               pdev->resource[0].end - pdev->resource[0].start + 1,
+                               pdev->name)) {
+               dev_dbg(&pdev->dev, "request_mem_region failed\n");
+               return -EBUSY;
+       }
+
+       mmc = mmc_alloc_host(sizeof(struct mmc_omap_host), &pdev->dev);
+       if (!mmc) {
+               ret = -ENOMEM;
+               goto out;
+       }
+
+       host = mmc_priv(mmc);
+       host->mmc = mmc;
+
+       spin_lock_init(&host->dma_lock);
+       init_timer(&host->dma_timer);
+       host->dma_timer.function = mmc_omap_dma_timer;
+       host->dma_timer.data = (unsigned long) host;
+
+       host->id = pdev->id;
+
+       if (cpu_is_omap24xx()) {
+               host->iclk = clk_get(&pdev->dev, "mmc_ick");
+               if (IS_ERR(host->iclk))
+                       goto out;
+               clk_enable(host->iclk);
+       }
+
+       if (!cpu_is_omap24xx())
+               host->fclk = clk_get(&pdev->dev, "mmc_ck");
+       else
+               host->fclk = clk_get(&pdev->dev, "mmc_fck");
+
+       if (IS_ERR(host->fclk)) {
+               ret = PTR_ERR(host->fclk);
+               goto out;
+       }
+
+       /* REVISIT:
+        * Also, use minfo->cover to decide how to manage
+        * the card detect sensing.
+        */
+       host->power_pin = minfo->power_pin;
+       host->switch_pin = minfo->switch_pin;
+       host->wp_pin = minfo->wp_pin;
+       host->use_dma = 1;
+       host->dma_ch = -1;
+
+       host->irq = pdev->resource[1].start;
+       host->base = ioremap(pdev->res.start, SZ_4K);
+       if (!host->base) {
+               ret = -ENOMEM;
+               goto out;
+       }
+
+        if (minfo->wire4)
+                mmc->caps |= MMC_CAP_4_BIT_DATA;
+
+       mmc->ops = &mmc_omap_ops;
+       mmc->f_min = 400000;
+       mmc->f_max = 24000000;
+       mmc->ocr_avail = MMC_VDD_32_33|MMC_VDD_33_34;
+
+       /* 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_sectors = 256; /* NBLK max 11-bits, OMAP also limited by DMA */
+       mmc->max_seg_size = mmc->max_sectors * 512;
+
+       if (host->power_pin >= 0) {
+               if ((ret = omap_request_gpio(host->power_pin)) != 0) {
+                       dev_err(mmc_dev(host->mmc), "Unable to get GPIO
+                                       pin for MMC power\n");
+                       goto out;
+               }
+               omap_set_gpio_direction(host->power_pin, 0);
+       }
+
+       ret = request_irq(host->irq, mmc_omap_irq, 0, DRIVER_NAME, host);
+       if (ret)
+               goto out;
+
+       host->dev = &pdev->dev;
+       platform_set_drvdata(pdev, host);
+
+       mmc_add_host(mmc);
+
+       if (host->switch_pin >= 0) {
+               INIT_WORK(&host->switch_work, mmc_omap_switch_handler, host);
+               init_timer(&host->switch_timer);
+               host->switch_timer.function = mmc_omap_switch_timer;
+               host->switch_timer.data = (unsigned long) host;
+               if (omap_request_gpio(host->switch_pin) != 0) {
+                       dev_warn(mmc_dev(host->mmc), "Unable to get GPIO pin for MMC cover switch\n");
+                       host->switch_pin = -1;
+                       goto no_switch;
+               }
+
+               omap_set_gpio_direction(host->switch_pin, 1);
+               ret = request_irq(OMAP_GPIO_IRQ(host->switch_pin),
+                                 mmc_omap_switch_irq, SA_TRIGGER_RISING, DRIVER_NAME, host);
+               if (ret) {
+                       dev_warn(mmc_dev(host->mmc), "Unable to get IRQ for MMC cover switch\n");
+                       omap_free_gpio(host->switch_pin);
+                       host->switch_pin = -1;
+                       goto no_switch;
+               }
+               ret = device_create_file(&pdev->dev, &dev_attr_cover_switch);
+               if (ret == 0) {
+                       ret = device_create_file(&pdev->dev, &dev_attr_enable_poll);
+                       if (ret != 0)
+                               device_remove_file(&pdev->dev, &dev_attr_cover_switch);
+               }
+               if (ret) {
+                       dev_wan(mmc_dev(host->mmc), "Unable to create sysfs attributes\n");
+                       free_irq(OMAP_GPIO_IRQ(host->switch_pin), host);
+                       omap_free_gpio(host->switch_pin);
+                       host->switch_pin = -1;
+                       goto no_switch;
+               }
+               if (mmc_omap_enable_poll && mmc_omap_cover_is_open(host))
+                       schedule_work(&host->switch_work);
+       }
+
+no_switch:
+       return 0;
+
+out:
+       /* FIXME: Free other resources too. */
+       if (host) {
+               if (host->iclk && !IS_ERR(host->iclk))
+                       clk_put(host->iclk);
+               if (host->fclk && !IS_ERR(host->fclk))
+                       clk_put(host->fclk);
+               mmc_free_host(host->mmc);
+       }
+       return ret;
+}
+
+static int mmc_omap_remove(struct platform_device *pdev)
+{
+       struct mmc_omap_host *host = platform_get_drvdata(pdev);
+
+       platform_set_drvdata(pdev, NULL);
+
+       if (host) {
+               mmc_remove_host(host->mmc);
+               free_irq(host->irq, host);
+
+               if (host->power_pin >= 0)
+                       omap_free_gpio(host->power_pin);
+               if (host->switch_pin >= 0) {
+                       device_remove_file(&pdev->dev, &dev_attr_enable_poll);
+                       device_remove_file(&pdev->dev, &dev_attr_cover_switch);
+                       free_irq(OMAP_GPIO_IRQ(host->switch_pin), host);
+                       omap_free_gpio(host->switch_pin);
+                       host->switch_pin = -1;
+                       del_timer_sync(&host->switch_timer);
+                       flush_scheduled_work();
+               }
+               if (host->iclk && !IS_ERR(host->iclk))
+                       clk_put(host->iclk);
+               if (host->fclk && !IS_ERR(host->fclk))
+                       clk_put(host->fclk);
+               mmc_free_host(host->mmc);
+       }
+
+       release_mem_region(pdev->resource[0].start,
+                       pdev->resource[0].end - pdev->resource[0].start + 1);
+
+       return 0;
+}
+
+#ifdef CONFIG_PM
+static int mmc_omap_suspend(struct platform_device *pdev, pm_message_t mesg)
+{
+       int ret = 0;
+       struct mmc_omap_host *host = platform_get_drvdata(pdev);
+
+       if (host && host->suspended)
+               return 0;
+
+       if (host) {
+               ret = mmc_suspend_host(host->mmc, mesg);
+               if (ret == 0)
+                       host->suspended = 1;
+       }
+       return ret;
+}
+
+static int mmc_omap_resume(struct platform_device *pdev)
+{
+       int ret = 0;
+       struct mmc_omap_host *host = platform_get_drvdata(pdev);
+
+       if (host && !host->suspended)
+               return 0;
+
+       if (host) {
+               ret = mmc_resume_host(host->mmc);
+               if (ret == 0)
+                       host->suspended = 0;
+       }
+
+       return ret;
+}
+#else
+#define mmc_omap_suspend       NULL
+#define mmc_omap_resume                NULL
+#endif
+
+static struct platform_driver mmc_omap_driver = {
+       .probe          = mmc_omap_probe,
+       .remove         = mmc_omap_remove,
+       .suspend        = mmc_omap_suspend,
+       .resume         = mmc_omap_resume,
+       .driver         = {
+               .name   = DRIVER_NAME,
+       },
+};
+
+static int __init mmc_omap_init(void)
+{
+       return platform_driver_register(&mmc_omap_driver);
+}
+
+static void __exit mmc_omap_exit(void)
+{
+       platform_driver_unregister(&mmc_omap_driver);
+}
+
+module_init(mmc_omap_init);
+module_exit(mmc_omap_exit);
+
+MODULE_DESCRIPTION("OMAP Multimedia Card driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS(DRIVER_NAME);
+MODULE_AUTHOR("Juha Yrjölä");