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authorIngo Molnar <mingo@elte.hu>2008-07-18 19:53:16 +0200
committerIngo Molnar <mingo@elte.hu>2008-07-18 19:53:16 +0200
commit9b610fda0df5d0f0b0c64242e37441ad1b384aac (patch)
tree0ea14b15f2e6546f37fe18d8ac3dc83077ec0e55 /drivers/mmc/host/atmel-mci.c
parentnohz: prevent tick stop outside of the idle loop (diff)
parentMerge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2 (diff)
downloadlinux-dev-9b610fda0df5d0f0b0c64242e37441ad1b384aac.tar.xz
linux-dev-9b610fda0df5d0f0b0c64242e37441ad1b384aac.zip
Merge branch 'linus' into timers/nohz
Diffstat (limited to 'drivers/mmc/host/atmel-mci.c')
-rw-r--r--drivers/mmc/host/atmel-mci.c981
1 files changed, 981 insertions, 0 deletions
diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
new file mode 100644
index 000000000000..cce873c5a149
--- /dev/null
+++ b/drivers/mmc/host/atmel-mci.c
@@ -0,0 +1,981 @@
+/*
+ * Atmel MultiMedia Card Interface driver
+ *
+ * Copyright (C) 2004-2008 Atmel Corporation
+ *
+ * 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/blkdev.h>
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/scatterlist.h>
+
+#include <linux/mmc/host.h>
+
+#include <asm/atmel-mci.h>
+#include <asm/io.h>
+#include <asm/unaligned.h>
+
+#include <asm/arch/board.h>
+#include <asm/arch/gpio.h>
+
+#include "atmel-mci-regs.h"
+
+#define ATMCI_DATA_ERROR_FLAGS (MCI_DCRCE | MCI_DTOE | MCI_OVRE | MCI_UNRE)
+
+enum {
+ EVENT_CMD_COMPLETE = 0,
+ EVENT_DATA_ERROR,
+ EVENT_DATA_COMPLETE,
+ EVENT_STOP_SENT,
+ EVENT_STOP_COMPLETE,
+ EVENT_XFER_COMPLETE,
+};
+
+struct atmel_mci {
+ struct mmc_host *mmc;
+ void __iomem *regs;
+
+ struct scatterlist *sg;
+ unsigned int pio_offset;
+
+ struct mmc_request *mrq;
+ struct mmc_command *cmd;
+ struct mmc_data *data;
+
+ u32 cmd_status;
+ u32 data_status;
+ u32 stop_status;
+ u32 stop_cmdr;
+
+ u32 mode_reg;
+ u32 sdc_reg;
+
+ struct tasklet_struct tasklet;
+ unsigned long pending_events;
+ unsigned long completed_events;
+
+ int present;
+ int detect_pin;
+ int wp_pin;
+
+ /* For detect pin debouncing */
+ struct timer_list detect_timer;
+
+ unsigned long bus_hz;
+ unsigned long mapbase;
+ struct clk *mck;
+ struct platform_device *pdev;
+};
+
+#define atmci_is_completed(host, event) \
+ test_bit(event, &host->completed_events)
+#define atmci_test_and_clear_pending(host, event) \
+ test_and_clear_bit(event, &host->pending_events)
+#define atmci_test_and_set_completed(host, event) \
+ test_and_set_bit(event, &host->completed_events)
+#define atmci_set_completed(host, event) \
+ set_bit(event, &host->completed_events)
+#define atmci_set_pending(host, event) \
+ set_bit(event, &host->pending_events)
+#define atmci_clear_pending(host, event) \
+ clear_bit(event, &host->pending_events)
+
+
+static void atmci_enable(struct atmel_mci *host)
+{
+ clk_enable(host->mck);
+ mci_writel(host, CR, MCI_CR_MCIEN);
+ mci_writel(host, MR, host->mode_reg);
+ mci_writel(host, SDCR, host->sdc_reg);
+}
+
+static void atmci_disable(struct atmel_mci *host)
+{
+ mci_writel(host, CR, MCI_CR_SWRST);
+
+ /* Stall until write is complete, then disable the bus clock */
+ mci_readl(host, SR);
+ clk_disable(host->mck);
+}
+
+static inline unsigned int ns_to_clocks(struct atmel_mci *host,
+ unsigned int ns)
+{
+ return (ns * (host->bus_hz / 1000000) + 999) / 1000;
+}
+
+static void atmci_set_timeout(struct atmel_mci *host,
+ struct mmc_data *data)
+{
+ static unsigned dtomul_to_shift[] = {
+ 0, 4, 7, 8, 10, 12, 16, 20
+ };
+ unsigned timeout;
+ unsigned dtocyc;
+ unsigned dtomul;
+
+ timeout = ns_to_clocks(host, data->timeout_ns) + data->timeout_clks;
+
+ for (dtomul = 0; dtomul < 8; dtomul++) {
+ unsigned shift = dtomul_to_shift[dtomul];
+ dtocyc = (timeout + (1 << shift) - 1) >> shift;
+ if (dtocyc < 15)
+ break;
+ }
+
+ if (dtomul >= 8) {
+ dtomul = 7;
+ dtocyc = 15;
+ }
+
+ dev_vdbg(&host->mmc->class_dev, "setting timeout to %u cycles\n",
+ dtocyc << dtomul_to_shift[dtomul]);
+ mci_writel(host, DTOR, (MCI_DTOMUL(dtomul) | MCI_DTOCYC(dtocyc)));
+}
+
+/*
+ * Return mask with command flags to be enabled for this command.
+ */
+static u32 atmci_prepare_command(struct mmc_host *mmc,
+ struct mmc_command *cmd)
+{
+ struct mmc_data *data;
+ u32 cmdr;
+
+ cmd->error = -EINPROGRESS;
+
+ cmdr = MCI_CMDR_CMDNB(cmd->opcode);
+
+ if (cmd->flags & MMC_RSP_PRESENT) {
+ if (cmd->flags & MMC_RSP_136)
+ cmdr |= MCI_CMDR_RSPTYP_136BIT;
+ else
+ cmdr |= MCI_CMDR_RSPTYP_48BIT;
+ }
+
+ /*
+ * This should really be MAXLAT_5 for CMD2 and ACMD41, but
+ * it's too difficult to determine whether this is an ACMD or
+ * not. Better make it 64.
+ */
+ cmdr |= MCI_CMDR_MAXLAT_64CYC;
+
+ if (mmc->ios.bus_mode == MMC_BUSMODE_OPENDRAIN)
+ cmdr |= MCI_CMDR_OPDCMD;
+
+ data = cmd->data;
+ if (data) {
+ cmdr |= MCI_CMDR_START_XFER;
+ if (data->flags & MMC_DATA_STREAM)
+ cmdr |= MCI_CMDR_STREAM;
+ else if (data->blocks > 1)
+ cmdr |= MCI_CMDR_MULTI_BLOCK;
+ else
+ cmdr |= MCI_CMDR_BLOCK;
+
+ if (data->flags & MMC_DATA_READ)
+ cmdr |= MCI_CMDR_TRDIR_READ;
+ }
+
+ return cmdr;
+}
+
+static void atmci_start_command(struct atmel_mci *host,
+ struct mmc_command *cmd,
+ u32 cmd_flags)
+{
+ /* Must read host->cmd after testing event flags */
+ smp_rmb();
+ WARN_ON(host->cmd);
+ host->cmd = cmd;
+
+ dev_vdbg(&host->mmc->class_dev,
+ "start command: ARGR=0x%08x CMDR=0x%08x\n",
+ cmd->arg, cmd_flags);
+
+ mci_writel(host, ARGR, cmd->arg);
+ mci_writel(host, CMDR, cmd_flags);
+}
+
+static void send_stop_cmd(struct mmc_host *mmc, struct mmc_data *data)
+{
+ struct atmel_mci *host = mmc_priv(mmc);
+
+ atmci_start_command(host, data->stop, host->stop_cmdr);
+ mci_writel(host, IER, MCI_CMDRDY);
+}
+
+static void atmci_request_end(struct mmc_host *mmc, struct mmc_request *mrq)
+{
+ struct atmel_mci *host = mmc_priv(mmc);
+
+ WARN_ON(host->cmd || host->data);
+ host->mrq = NULL;
+
+ atmci_disable(host);
+
+ mmc_request_done(mmc, mrq);
+}
+
+/*
+ * Returns a mask of interrupt flags to be enabled after the whole
+ * request has been prepared.
+ */
+static u32 atmci_submit_data(struct mmc_host *mmc, struct mmc_data *data)
+{
+ struct atmel_mci *host = mmc_priv(mmc);
+ u32 iflags;
+
+ data->error = -EINPROGRESS;
+
+ WARN_ON(host->data);
+ host->sg = NULL;
+ host->data = data;
+
+ mci_writel(host, BLKR, MCI_BCNT(data->blocks)
+ | MCI_BLKLEN(data->blksz));
+ dev_vdbg(&mmc->class_dev, "BLKR=0x%08x\n",
+ MCI_BCNT(data->blocks) | MCI_BLKLEN(data->blksz));
+
+ iflags = ATMCI_DATA_ERROR_FLAGS;
+ host->sg = data->sg;
+ host->pio_offset = 0;
+ if (data->flags & MMC_DATA_READ)
+ iflags |= MCI_RXRDY;
+ else
+ iflags |= MCI_TXRDY;
+
+ return iflags;
+}
+
+static void atmci_request(struct mmc_host *mmc, struct mmc_request *mrq)
+{
+ struct atmel_mci *host = mmc_priv(mmc);
+ struct mmc_data *data;
+ struct mmc_command *cmd;
+ u32 iflags;
+ u32 cmdflags = 0;
+
+ iflags = mci_readl(host, IMR);
+ if (iflags)
+ dev_warn(&mmc->class_dev, "WARNING: IMR=0x%08x\n",
+ mci_readl(host, IMR));
+
+ WARN_ON(host->mrq != NULL);
+
+ /*
+ * We may "know" the card is gone even though there's still an
+ * electrical connection. If so, we really need to communicate
+ * this to the MMC core since there won't be any more
+ * interrupts as the card is completely removed. Otherwise,
+ * the MMC core might believe the card is still there even
+ * though the card was just removed very slowly.
+ */
+ if (!host->present) {
+ mrq->cmd->error = -ENOMEDIUM;
+ mmc_request_done(mmc, mrq);
+ return;
+ }
+
+ host->mrq = mrq;
+ host->pending_events = 0;
+ host->completed_events = 0;
+
+ atmci_enable(host);
+
+ /* We don't support multiple blocks of weird lengths. */
+ data = mrq->data;
+ if (data) {
+ if (data->blocks > 1 && data->blksz & 3)
+ goto fail;
+ atmci_set_timeout(host, data);
+ }
+
+ iflags = MCI_CMDRDY;
+ cmd = mrq->cmd;
+ cmdflags = atmci_prepare_command(mmc, cmd);
+ atmci_start_command(host, cmd, cmdflags);
+
+ if (data)
+ iflags |= atmci_submit_data(mmc, data);
+
+ if (mrq->stop) {
+ host->stop_cmdr = atmci_prepare_command(mmc, mrq->stop);
+ host->stop_cmdr |= MCI_CMDR_STOP_XFER;
+ if (!(data->flags & MMC_DATA_WRITE))
+ host->stop_cmdr |= MCI_CMDR_TRDIR_READ;
+ if (data->flags & MMC_DATA_STREAM)
+ host->stop_cmdr |= MCI_CMDR_STREAM;
+ else
+ host->stop_cmdr |= MCI_CMDR_MULTI_BLOCK;
+ }
+
+ /*
+ * We could have enabled interrupts earlier, but I suspect
+ * that would open up a nice can of interesting race
+ * conditions (e.g. command and data complete, but stop not
+ * prepared yet.)
+ */
+ mci_writel(host, IER, iflags);
+
+ return;
+
+fail:
+ atmci_disable(host);
+ host->mrq = NULL;
+ mrq->cmd->error = -EINVAL;
+ mmc_request_done(mmc, mrq);
+}
+
+static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
+{
+ struct atmel_mci *host = mmc_priv(mmc);
+
+ if (ios->clock) {
+ u32 clkdiv;
+
+ /* Set clock rate */
+ clkdiv = DIV_ROUND_UP(host->bus_hz, 2 * ios->clock) - 1;
+ if (clkdiv > 255) {
+ dev_warn(&mmc->class_dev,
+ "clock %u too slow; using %lu\n",
+ ios->clock, host->bus_hz / (2 * 256));
+ clkdiv = 255;
+ }
+
+ host->mode_reg = MCI_MR_CLKDIV(clkdiv) | MCI_MR_WRPROOF
+ | MCI_MR_RDPROOF;
+ }
+
+ switch (ios->bus_width) {
+ case MMC_BUS_WIDTH_1:
+ host->sdc_reg = 0;
+ break;
+ case MMC_BUS_WIDTH_4:
+ host->sdc_reg = MCI_SDCBUS_4BIT;
+ break;
+ }
+
+ switch (ios->power_mode) {
+ case MMC_POWER_ON:
+ /* Send init sequence (74 clock cycles) */
+ atmci_enable(host);
+ mci_writel(host, CMDR, MCI_CMDR_SPCMD_INIT);
+ while (!(mci_readl(host, SR) & MCI_CMDRDY))
+ cpu_relax();
+ atmci_disable(host);
+ break;
+ default:
+ /*
+ * TODO: None of the currently available AVR32-based
+ * boards allow MMC power to be turned off. Implement
+ * power control when this can be tested properly.
+ */
+ break;
+ }
+}
+
+static int atmci_get_ro(struct mmc_host *mmc)
+{
+ int read_only = 0;
+ struct atmel_mci *host = mmc_priv(mmc);
+
+ if (host->wp_pin >= 0) {
+ read_only = gpio_get_value(host->wp_pin);
+ dev_dbg(&mmc->class_dev, "card is %s\n",
+ read_only ? "read-only" : "read-write");
+ } else {
+ dev_dbg(&mmc->class_dev,
+ "no pin for checking read-only switch."
+ " Assuming write-enable.\n");
+ }
+
+ return read_only;
+}
+
+static struct mmc_host_ops atmci_ops = {
+ .request = atmci_request,
+ .set_ios = atmci_set_ios,
+ .get_ro = atmci_get_ro,
+};
+
+static void atmci_command_complete(struct atmel_mci *host,
+ struct mmc_command *cmd, u32 status)
+{
+ /* Read the response from the card (up to 16 bytes) */
+ cmd->resp[0] = mci_readl(host, RSPR);
+ cmd->resp[1] = mci_readl(host, RSPR);
+ cmd->resp[2] = mci_readl(host, RSPR);
+ cmd->resp[3] = mci_readl(host, RSPR);
+
+ if (status & MCI_RTOE)
+ cmd->error = -ETIMEDOUT;
+ else if ((cmd->flags & MMC_RSP_CRC) && (status & MCI_RCRCE))
+ cmd->error = -EILSEQ;
+ else if (status & (MCI_RINDE | MCI_RDIRE | MCI_RENDE))
+ cmd->error = -EIO;
+ else
+ cmd->error = 0;
+
+ if (cmd->error) {
+ dev_dbg(&host->mmc->class_dev,
+ "command error: status=0x%08x\n", status);
+
+ if (cmd->data) {
+ host->data = NULL;
+ mci_writel(host, IDR, MCI_NOTBUSY
+ | MCI_TXRDY | MCI_RXRDY
+ | ATMCI_DATA_ERROR_FLAGS);
+ }
+ }
+}
+
+static void atmci_detect_change(unsigned long data)
+{
+ struct atmel_mci *host = (struct atmel_mci *)data;
+ struct mmc_request *mrq = host->mrq;
+ int present;
+
+ /*
+ * atmci_remove() sets detect_pin to -1 before freeing the
+ * interrupt. We must not re-enable the interrupt if it has
+ * been freed.
+ */
+ smp_rmb();
+ if (host->detect_pin < 0)
+ return;
+
+ enable_irq(gpio_to_irq(host->detect_pin));
+ present = !gpio_get_value(host->detect_pin);
+
+ dev_vdbg(&host->pdev->dev, "detect change: %d (was %d)\n",
+ present, host->present);
+
+ if (present != host->present) {
+ dev_dbg(&host->mmc->class_dev, "card %s\n",
+ present ? "inserted" : "removed");
+ host->present = present;
+
+ /* Reset controller if card is gone */
+ if (!present) {
+ mci_writel(host, CR, MCI_CR_SWRST);
+ mci_writel(host, IDR, ~0UL);
+ mci_writel(host, CR, MCI_CR_MCIEN);
+ }
+
+ /* Clean up queue if present */
+ if (mrq) {
+ /*
+ * Reset controller to terminate any ongoing
+ * commands or data transfers.
+ */
+ mci_writel(host, CR, MCI_CR_SWRST);
+
+ if (!atmci_is_completed(host, EVENT_CMD_COMPLETE))
+ mrq->cmd->error = -ENOMEDIUM;
+
+ if (mrq->data && !atmci_is_completed(host,
+ EVENT_DATA_COMPLETE)) {
+ host->data = NULL;
+ mrq->data->error = -ENOMEDIUM;
+ }
+ if (mrq->stop && !atmci_is_completed(host,
+ EVENT_STOP_COMPLETE))
+ mrq->stop->error = -ENOMEDIUM;
+
+ host->cmd = NULL;
+ atmci_request_end(host->mmc, mrq);
+ }
+
+ mmc_detect_change(host->mmc, 0);
+ }
+}
+
+static void atmci_tasklet_func(unsigned long priv)
+{
+ struct mmc_host *mmc = (struct mmc_host *)priv;
+ struct atmel_mci *host = mmc_priv(mmc);
+ struct mmc_request *mrq = host->mrq;
+ struct mmc_data *data = host->data;
+
+ dev_vdbg(&mmc->class_dev,
+ "tasklet: pending/completed/mask %lx/%lx/%x\n",
+ host->pending_events, host->completed_events,
+ mci_readl(host, IMR));
+
+ if (atmci_test_and_clear_pending(host, EVENT_CMD_COMPLETE)) {
+ /*
+ * host->cmd must be set to NULL before the interrupt
+ * handler sees EVENT_CMD_COMPLETE
+ */
+ host->cmd = NULL;
+ smp_wmb();
+ atmci_set_completed(host, EVENT_CMD_COMPLETE);
+ atmci_command_complete(host, mrq->cmd, host->cmd_status);
+
+ if (!mrq->cmd->error && mrq->stop
+ && atmci_is_completed(host, EVENT_XFER_COMPLETE)
+ && !atmci_test_and_set_completed(host,
+ EVENT_STOP_SENT))
+ send_stop_cmd(host->mmc, mrq->data);
+ }
+ if (atmci_test_and_clear_pending(host, EVENT_STOP_COMPLETE)) {
+ /*
+ * host->cmd must be set to NULL before the interrupt
+ * handler sees EVENT_STOP_COMPLETE
+ */
+ host->cmd = NULL;
+ smp_wmb();
+ atmci_set_completed(host, EVENT_STOP_COMPLETE);
+ atmci_command_complete(host, mrq->stop, host->stop_status);
+ }
+ if (atmci_test_and_clear_pending(host, EVENT_DATA_ERROR)) {
+ u32 status = host->data_status;
+
+ dev_vdbg(&mmc->class_dev, "data error: status=%08x\n", status);
+
+ atmci_set_completed(host, EVENT_DATA_ERROR);
+ atmci_set_completed(host, EVENT_DATA_COMPLETE);
+
+ if (status & MCI_DTOE) {
+ dev_dbg(&mmc->class_dev,
+ "data timeout error\n");
+ data->error = -ETIMEDOUT;
+ } else if (status & MCI_DCRCE) {
+ dev_dbg(&mmc->class_dev, "data CRC error\n");
+ data->error = -EILSEQ;
+ } else {
+ dev_dbg(&mmc->class_dev,
+ "data FIFO error (status=%08x)\n",
+ status);
+ data->error = -EIO;
+ }
+
+ if (host->present && data->stop
+ && atmci_is_completed(host, EVENT_CMD_COMPLETE)
+ && !atmci_test_and_set_completed(
+ host, EVENT_STOP_SENT))
+ send_stop_cmd(host->mmc, data);
+
+ host->data = NULL;
+ }
+ if (atmci_test_and_clear_pending(host, EVENT_DATA_COMPLETE)) {
+ atmci_set_completed(host, EVENT_DATA_COMPLETE);
+
+ if (!atmci_is_completed(host, EVENT_DATA_ERROR)) {
+ data->bytes_xfered = data->blocks * data->blksz;
+ data->error = 0;
+ }
+
+ host->data = NULL;
+ }
+
+ if (host->mrq && !host->cmd && !host->data)
+ atmci_request_end(mmc, host->mrq);
+}
+
+static void atmci_read_data_pio(struct atmel_mci *host)
+{
+ struct scatterlist *sg = host->sg;
+ void *buf = sg_virt(sg);
+ unsigned int offset = host->pio_offset;
+ struct mmc_data *data = host->data;
+ u32 value;
+ u32 status;
+ unsigned int nbytes = 0;
+
+ do {
+ value = mci_readl(host, RDR);
+ if (likely(offset + 4 <= sg->length)) {
+ put_unaligned(value, (u32 *)(buf + offset));
+
+ offset += 4;
+ nbytes += 4;
+
+ if (offset == sg->length) {
+ host->sg = sg = sg_next(sg);
+ if (!sg)
+ goto done;
+
+ offset = 0;
+ buf = sg_virt(sg);
+ }
+ } else {
+ unsigned int remaining = sg->length - offset;
+ memcpy(buf + offset, &value, remaining);
+ nbytes += remaining;
+
+ flush_dcache_page(sg_page(sg));
+ host->sg = sg = sg_next(sg);
+ if (!sg)
+ goto done;
+
+ offset = 4 - remaining;
+ buf = sg_virt(sg);
+ memcpy(buf, (u8 *)&value + remaining, offset);
+ nbytes += offset;
+ }
+
+ status = mci_readl(host, SR);
+ if (status & ATMCI_DATA_ERROR_FLAGS) {
+ mci_writel(host, IDR, (MCI_NOTBUSY | MCI_RXRDY
+ | ATMCI_DATA_ERROR_FLAGS));
+ host->data_status = status;
+ atmci_set_pending(host, EVENT_DATA_ERROR);
+ tasklet_schedule(&host->tasklet);
+ break;
+ }
+ } while (status & MCI_RXRDY);
+
+ host->pio_offset = offset;
+ data->bytes_xfered += nbytes;
+
+ return;
+
+done:
+ mci_writel(host, IDR, MCI_RXRDY);
+ mci_writel(host, IER, MCI_NOTBUSY);
+ data->bytes_xfered += nbytes;
+ atmci_set_completed(host, EVENT_XFER_COMPLETE);
+ if (data->stop && atmci_is_completed(host, EVENT_CMD_COMPLETE)
+ && !atmci_test_and_set_completed(host, EVENT_STOP_SENT))
+ send_stop_cmd(host->mmc, data);
+}
+
+static void atmci_write_data_pio(struct atmel_mci *host)
+{
+ struct scatterlist *sg = host->sg;
+ void *buf = sg_virt(sg);
+ unsigned int offset = host->pio_offset;
+ struct mmc_data *data = host->data;
+ u32 value;
+ u32 status;
+ unsigned int nbytes = 0;
+
+ do {
+ if (likely(offset + 4 <= sg->length)) {
+ value = get_unaligned((u32 *)(buf + offset));
+ mci_writel(host, TDR, value);
+
+ offset += 4;
+ nbytes += 4;
+ if (offset == sg->length) {
+ host->sg = sg = sg_next(sg);
+ if (!sg)
+ goto done;
+
+ offset = 0;
+ buf = sg_virt(sg);
+ }
+ } else {
+ unsigned int remaining = sg->length - offset;
+
+ value = 0;
+ memcpy(&value, buf + offset, remaining);
+ nbytes += remaining;
+
+ host->sg = sg = sg_next(sg);
+ if (!sg) {
+ mci_writel(host, TDR, value);
+ goto done;
+ }
+
+ offset = 4 - remaining;
+ buf = sg_virt(sg);
+ memcpy((u8 *)&value + remaining, buf, offset);
+ mci_writel(host, TDR, value);
+ nbytes += offset;
+ }
+
+ status = mci_readl(host, SR);
+ if (status & ATMCI_DATA_ERROR_FLAGS) {
+ mci_writel(host, IDR, (MCI_NOTBUSY | MCI_TXRDY
+ | ATMCI_DATA_ERROR_FLAGS));
+ host->data_status = status;
+ atmci_set_pending(host, EVENT_DATA_ERROR);
+ tasklet_schedule(&host->tasklet);
+ break;
+ }
+ } while (status & MCI_TXRDY);
+
+ host->pio_offset = offset;
+ data->bytes_xfered += nbytes;
+
+ return;
+
+done:
+ mci_writel(host, IDR, MCI_TXRDY);
+ mci_writel(host, IER, MCI_NOTBUSY);
+ data->bytes_xfered += nbytes;
+ atmci_set_completed(host, EVENT_XFER_COMPLETE);
+ if (data->stop && atmci_is_completed(host, EVENT_CMD_COMPLETE)
+ && !atmci_test_and_set_completed(host, EVENT_STOP_SENT))
+ send_stop_cmd(host->mmc, data);
+}
+
+static void atmci_cmd_interrupt(struct mmc_host *mmc, u32 status)
+{
+ struct atmel_mci *host = mmc_priv(mmc);
+
+ mci_writel(host, IDR, MCI_CMDRDY);
+
+ if (atmci_is_completed(host, EVENT_STOP_SENT)) {
+ host->stop_status = status;
+ atmci_set_pending(host, EVENT_STOP_COMPLETE);
+ } else {
+ host->cmd_status = status;
+ atmci_set_pending(host, EVENT_CMD_COMPLETE);
+ }
+
+ tasklet_schedule(&host->tasklet);
+}
+
+static irqreturn_t atmci_interrupt(int irq, void *dev_id)
+{
+ struct mmc_host *mmc = dev_id;
+ struct atmel_mci *host = mmc_priv(mmc);
+ u32 status, mask, pending;
+ unsigned int pass_count = 0;
+
+ spin_lock(&mmc->lock);
+
+ do {
+ status = mci_readl(host, SR);
+ mask = mci_readl(host, IMR);
+ pending = status & mask;
+ if (!pending)
+ break;
+
+ if (pending & ATMCI_DATA_ERROR_FLAGS) {
+ mci_writel(host, IDR, ATMCI_DATA_ERROR_FLAGS
+ | MCI_RXRDY | MCI_TXRDY);
+ pending &= mci_readl(host, IMR);
+ host->data_status = status;
+ atmci_set_pending(host, EVENT_DATA_ERROR);
+ tasklet_schedule(&host->tasklet);
+ }
+ if (pending & MCI_NOTBUSY) {
+ mci_writel(host, IDR, (MCI_NOTBUSY
+ | ATMCI_DATA_ERROR_FLAGS));
+ atmci_set_pending(host, EVENT_DATA_COMPLETE);
+ tasklet_schedule(&host->tasklet);
+ }
+ if (pending & MCI_RXRDY)
+ atmci_read_data_pio(host);
+ if (pending & MCI_TXRDY)
+ atmci_write_data_pio(host);
+
+ if (pending & MCI_CMDRDY)
+ atmci_cmd_interrupt(mmc, status);
+ } while (pass_count++ < 5);
+
+ spin_unlock(&mmc->lock);
+
+ return pass_count ? IRQ_HANDLED : IRQ_NONE;
+}
+
+static irqreturn_t atmci_detect_interrupt(int irq, void *dev_id)
+{
+ struct mmc_host *mmc = dev_id;
+ struct atmel_mci *host = mmc_priv(mmc);
+
+ /*
+ * Disable interrupts until the pin has stabilized and check
+ * the state then. Use mod_timer() since we may be in the
+ * middle of the timer routine when this interrupt triggers.
+ */
+ disable_irq_nosync(irq);
+ mod_timer(&host->detect_timer, jiffies + msecs_to_jiffies(20));
+
+ return IRQ_HANDLED;
+}
+
+static int __init atmci_probe(struct platform_device *pdev)
+{
+ struct mci_platform_data *pdata;
+ struct atmel_mci *host;
+ struct mmc_host *mmc;
+ struct resource *regs;
+ int irq;
+ int ret;
+
+ regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!regs)
+ return -ENXIO;
+ pdata = pdev->dev.platform_data;
+ if (!pdata)
+ return -ENXIO;
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+
+ mmc = mmc_alloc_host(sizeof(struct atmel_mci), &pdev->dev);
+ if (!mmc)
+ return -ENOMEM;
+
+ host = mmc_priv(mmc);
+ host->pdev = pdev;
+ host->mmc = mmc;
+ host->detect_pin = pdata->detect_pin;
+ host->wp_pin = pdata->wp_pin;
+
+ host->mck = clk_get(&pdev->dev, "mci_clk");
+ if (IS_ERR(host->mck)) {
+ ret = PTR_ERR(host->mck);
+ goto err_clk_get;
+ }
+
+ ret = -ENOMEM;
+ host->regs = ioremap(regs->start, regs->end - regs->start + 1);
+ if (!host->regs)
+ goto err_ioremap;
+
+ clk_enable(host->mck);
+ mci_writel(host, CR, MCI_CR_SWRST);
+ host->bus_hz = clk_get_rate(host->mck);
+ clk_disable(host->mck);
+
+ host->mapbase = regs->start;
+
+ mmc->ops = &atmci_ops;
+ mmc->f_min = (host->bus_hz + 511) / 512;
+ mmc->f_max = host->bus_hz / 2;
+ mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
+ mmc->caps |= MMC_CAP_4_BIT_DATA;
+
+ mmc->max_hw_segs = 64;
+ mmc->max_phys_segs = 64;
+ mmc->max_req_size = 32768 * 512;
+ mmc->max_blk_size = 32768;
+ mmc->max_blk_count = 512;
+
+ tasklet_init(&host->tasklet, atmci_tasklet_func, (unsigned long)mmc);
+
+ ret = request_irq(irq, atmci_interrupt, 0, pdev->dev.bus_id, mmc);
+ if (ret)
+ goto err_request_irq;
+
+ /* Assume card is present if we don't have a detect pin */
+ host->present = 1;
+ if (host->detect_pin >= 0) {
+ if (gpio_request(host->detect_pin, "mmc_detect")) {
+ dev_dbg(&mmc->class_dev, "no detect pin available\n");
+ host->detect_pin = -1;
+ } else {
+ host->present = !gpio_get_value(host->detect_pin);
+ }
+ }
+ if (host->wp_pin >= 0) {
+ if (gpio_request(host->wp_pin, "mmc_wp")) {
+ dev_dbg(&mmc->class_dev, "no WP pin available\n");
+ host->wp_pin = -1;
+ }
+ }
+
+ platform_set_drvdata(pdev, host);
+
+ mmc_add_host(mmc);
+
+ if (host->detect_pin >= 0) {
+ setup_timer(&host->detect_timer, atmci_detect_change,
+ (unsigned long)host);
+
+ ret = request_irq(gpio_to_irq(host->detect_pin),
+ atmci_detect_interrupt,
+ IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
+ "mmc-detect", mmc);
+ if (ret) {
+ dev_dbg(&mmc->class_dev,
+ "could not request IRQ %d for detect pin\n",
+ gpio_to_irq(host->detect_pin));
+ gpio_free(host->detect_pin);
+ host->detect_pin = -1;
+ }
+ }
+
+ dev_info(&mmc->class_dev,
+ "Atmel MCI controller at 0x%08lx irq %d\n",
+ host->mapbase, irq);
+
+ return 0;
+
+err_request_irq:
+ iounmap(host->regs);
+err_ioremap:
+ clk_put(host->mck);
+err_clk_get:
+ mmc_free_host(mmc);
+ return ret;
+}
+
+static int __exit atmci_remove(struct platform_device *pdev)
+{
+ struct atmel_mci *host = platform_get_drvdata(pdev);
+
+ platform_set_drvdata(pdev, NULL);
+
+ if (host) {
+ if (host->detect_pin >= 0) {
+ int pin = host->detect_pin;
+
+ /* Make sure the timer doesn't enable the interrupt */
+ host->detect_pin = -1;
+ smp_wmb();
+
+ free_irq(gpio_to_irq(pin), host->mmc);
+ del_timer_sync(&host->detect_timer);
+ gpio_free(pin);
+ }
+
+ mmc_remove_host(host->mmc);
+
+ clk_enable(host->mck);
+ mci_writel(host, IDR, ~0UL);
+ mci_writel(host, CR, MCI_CR_MCIDIS);
+ mci_readl(host, SR);
+ clk_disable(host->mck);
+
+ if (host->wp_pin >= 0)
+ gpio_free(host->wp_pin);
+
+ free_irq(platform_get_irq(pdev, 0), host->mmc);
+ iounmap(host->regs);
+
+ clk_put(host->mck);
+
+ mmc_free_host(host->mmc);
+ }
+ return 0;
+}
+
+static struct platform_driver atmci_driver = {
+ .remove = __exit_p(atmci_remove),
+ .driver = {
+ .name = "atmel_mci",
+ },
+};
+
+static int __init atmci_init(void)
+{
+ return platform_driver_probe(&atmci_driver, atmci_probe);
+}
+
+static void __exit atmci_exit(void)
+{
+ platform_driver_unregister(&atmci_driver);
+}
+
+module_init(atmci_init);
+module_exit(atmci_exit);
+
+MODULE_DESCRIPTION("Atmel Multimedia Card Interface driver");
+MODULE_AUTHOR("Haavard Skinnemoen <haavard.skinnemoen@atmel.com>");
+MODULE_LICENSE("GPL v2");