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Message-Id: <1222101497-21183-4-git-send-email-haavard.skinnemoen@atmel.com>
Date: Mon, 22 Sep 2008 18:38:16 +0200
From: Haavard Skinnemoen <haavard.skinnemoen@...el.com>
To: Pierre Ossman <drzeus-list@...eus.cx>
Cc: kernel@...32linux.org, linux-kernel@...r.kernel.org,
Haavard Skinnemoen <haavard.skinnemoen@...el.com>
Subject: [PATCH 3/4] atmel-mci: support multiple mmc slots
The Atmel MCI controller can drive multiple cards through separate sets
of pins, but only one at a time. This patch adds support for
multiplexing access to the controller so that multiple card slots can be
used as if they were hooked up to separate mmc controllers.
The atmel-mci driver registers each slot as a separate mmc_host. Both
access the same common controller state, but they also have some state
on their own for card detection/write protect handling, and separate
shadows of the MR and SDCR registers.
When one of the slots receives a request from the mmc core, the common
controller state is checked. If it's idle, the request is submitted
immediately. If not, the request is added to a queue. When a request is
done, the queue is checked and if there is a queued request, it is
submitted before the completion callback is called.
This patch also includes a few cleanups and fixes, including a locking
overhaul. I had to change the locking extensively in any case, so I
might as well try to get it right. The driver no longer takes any
irq-safe locks, which may or may not improve the overall system
performance.
This patch also adds a bit of documentation of the internal data
structures.
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@...el.com>
---
drivers/mmc/host/atmel-mci.c | 851 ++++++++++++++++++++++++++----------------
1 files changed, 525 insertions(+), 326 deletions(-)
diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
index e2d321a..a7de55f 100644
--- a/drivers/mmc/host/atmel-mci.c
+++ b/drivers/mmc/host/atmel-mci.c
@@ -42,20 +42,81 @@ enum {
};
enum atmel_mci_state {
- STATE_SENDING_CMD = 0,
+ STATE_IDLE = 0,
+ STATE_SENDING_CMD,
STATE_SENDING_DATA,
STATE_DATA_BUSY,
STATE_SENDING_STOP,
STATE_DATA_ERROR,
};
+/**
+ * struct atmel_mci - MMC controller state shared between all slots
+ * @lock: Spinlock protecting the queue and associated data.
+ * @regs: Pointer to MMIO registers.
+ * @sg: Scatterlist entry currently being processed by PIO code, if any.
+ * @pio_offset: Offset into the current scatterlist entry.
+ * @cur_slot: The slot which is currently using the controller.
+ * @mrq: The request currently being processed on @cur_slot,
+ * or NULL if the controller is idle.
+ * @cmd: The command currently being sent to the card, or NULL.
+ * @data: The data currently being transferred, or NULL if no data
+ * transfer is in progress.
+ * @dma: DMA client state.
+ * @data_chan: DMA channel being used for the current data transfer.
+ * @cmd_status: Snapshot of SR taken upon completion of the current
+ * command. Only valid when EVENT_CMD_COMPLETE is pending.
+ * @data_status: Snapshot of SR taken upon completion of the current
+ * data transfer. Only valid when EVENT_DATA_COMPLETE or
+ * EVENT_DATA_ERROR is pending.
+ * @stop_cmdr: Value to be loaded into CMDR when the stop command is
+ * to be sent.
+ * @tasklet: Tasklet running the request state machine.
+ * @pending_events: Bitmask of events flagged by the interrupt handler
+ * to be processed by the tasklet.
+ * @completed_events: Bitmask of events which the state machine has
+ * processed.
+ * @state: Tasklet state.
+ * @queue: List of slots waiting for access to the controller.
+ * @bus_hz: The rate of @mck in Hz. This forms the basis for MMC bus
+ * rate and timeout calculations.
+ * @mapbase: Physical address of the MMIO registers.
+ * @mck: The peripheral bus clock hooked up to the MMC controller.
+ * @pdev: Platform device associated with the MMC controller.
+ * @slots: List of all slots sharing this MMC controller.
+ *
+ * Locking
+ * =======
+ *
+ * @lock is a softirq-safe spinlock protecting @queue as well as
+ * @cur_slot, @mrq and @state. These must always be updated
+ * at the same time while holding @lock.
+ *
+ * The @mrq field of struct atmel_mci_slot is also protected by @lock,
+ * and must always be written at the same time as the slot is added to
+ * @queue.
+ *
+ * @pending_events and @completed_events are accessed using atomic bit
+ * operations, so they don't need any locking.
+ *
+ * None of the fields touched by the interrupt handler need any
+ * locking. However, ordering is important: Before EVENT_DATA_ERROR or
+ * EVENT_DATA_COMPLETE is set in @pending_events, all data-related
+ * interrupts must be disabled and @data_status updated with a
+ * snapshot of SR. Similarly, before EVENT_CMD_COMPLETE is set, the
+ * CMDRDY interupt must be disabled and @cmd_status updated with a
+ * snapshot of SR, and before EVENT_XFER_COMPLETE can be set, the
+ * bytes_xfered field of @data must be written. This is ensured by
+ * using barriers.
+ */
struct atmel_mci {
- struct mmc_host *mmc;
+ spinlock_t lock;
void __iomem *regs;
struct scatterlist *sg;
unsigned int pio_offset;
+ struct atmel_mci_slot *cur_slot;
struct mmc_request *mrq;
struct mmc_command *cmd;
struct mmc_data *data;
@@ -64,25 +125,60 @@ struct atmel_mci {
u32 data_status;
u32 stop_cmdr;
- u32 mode_reg;
- u32 sdc_reg;
-
struct tasklet_struct tasklet;
unsigned long pending_events;
unsigned long completed_events;
enum atmel_mci_state state;
+ struct list_head queue;
+
+ unsigned long bus_hz;
+ unsigned long mapbase;
+ struct clk *mck;
+ struct platform_device *pdev;
+
+ struct list_head slots;
+};
+
+/**
+ * struct atmel_mci_slot - MMC slot state
+ * @mmc: The mmc_host representing this slot.
+ * @host: The MMC controller this slot is using.
+ * @mode_reg: Value of MR to be written before using this slot.
+ * @sdc_reg: Value of SDCR to be written before using this slot.
+ * @mrq: mmc_request currently being processed or waiting to be
+ * processed, or NULL when the slot is idle.
+ * @queue_node: List node for placing this node in the @queue list of
+ * &struct atmel_mci.
+ * @flags: Random state bits associated with the slot.
+ * @detect_pin: GPIO pin used for card detection, or negative if not
+ * available.
+ * @wp_pin: GPIO pin used for card write protect sending, or negative
+ * if not available.
+ * @detect_timer: Timer used for debouncing @detect_pin interrupts.
+ * @slot_node: List node for placing this node in the @slots list of
+ * &struct atmel_mci.
+ */
+struct atmel_mci_slot {
+ struct mmc_host *mmc;
+ struct atmel_mci *host;
+
+ u32 mode_reg;
+ u32 sdc_reg;
+
+ struct mmc_request *mrq;
+ struct list_head queue_node;
+
+ unsigned long flags;
+#define ATMCI_CARD_PRESENT 0
+#define ATMCI_CARD_NEED_INIT 1
+#define ATMCI_SHUTDOWN 2
- 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;
+ struct list_head slot_node;
};
#define atmci_test_and_clear_pending(host, event) \
@@ -98,14 +194,15 @@ struct atmel_mci {
*/
static int atmci_req_show(struct seq_file *s, void *v)
{
- struct atmel_mci *host = s->private;
- struct mmc_request *mrq = host->mrq;
+ struct atmel_mci_slot *slot = s->private;
+ struct mmc_request *mrq;
struct mmc_command *cmd;
struct mmc_command *stop;
struct mmc_data *data;
/* Make sure we get a consistent snapshot */
- spin_lock_irq(&host->mmc->lock);
+ spin_lock_bh(&slot->host->lock);
+ mrq = slot->mrq;
if (mrq) {
cmd = mrq->cmd;
@@ -130,7 +227,7 @@ static int atmci_req_show(struct seq_file *s, void *v)
stop->resp[2], stop->error);
}
- spin_unlock_irq(&host->mmc->lock);
+ spin_unlock_bh(&slot->host->lock);
return 0;
}
@@ -193,12 +290,16 @@ static int atmci_regs_show(struct seq_file *s, void *v)
if (!buf)
return -ENOMEM;
- /* Grab a more or less consistent snapshot */
- spin_lock_irq(&host->mmc->lock);
+ /*
+ * Grab a more or less consistent snapshot. Note that we're
+ * not disabling interrupts, so IMR and SR may not be
+ * consistent.
+ */
+ spin_lock_bh(&host->lock);
clk_enable(host->mck);
memcpy_fromio(buf, host->regs, MCI_REGS_SIZE);
clk_disable(host->mck);
- spin_unlock_irq(&host->mmc->lock);
+ spin_unlock_bh(&host->lock);
seq_printf(s, "MR:\t0x%08x%s%s CLKDIV=%u\n",
buf[MCI_MR / 4],
@@ -236,13 +337,13 @@ static const struct file_operations atmci_regs_fops = {
.release = single_release,
};
-static void atmci_init_debugfs(struct atmel_mci *host)
+static void atmci_init_debugfs(struct atmel_mci_slot *slot)
{
- struct mmc_host *mmc;
- struct dentry *root;
- struct dentry *node;
+ struct mmc_host *mmc = slot->mmc;
+ struct atmel_mci *host = slot->host;
+ struct dentry *root;
+ struct dentry *node;
- mmc = host->mmc;
root = mmc->debugfs_root;
if (!root)
return;
@@ -254,7 +355,7 @@ static void atmci_init_debugfs(struct atmel_mci *host)
if (!node)
goto err;
- node = debugfs_create_file("req", S_IRUSR, root, host, &atmci_req_fops);
+ node = debugfs_create_file("req", S_IRUSR, root, slot, &atmci_req_fops);
if (!node)
goto err;
@@ -275,25 +376,7 @@ static void atmci_init_debugfs(struct atmel_mci *host)
return;
err:
- dev_err(&host->pdev->dev,
- "failed to initialize debugfs for controller\n");
-}
-
-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);
+ dev_err(&mmc->class_dev, "failed to initialize debugfs for slot\n");
}
static inline unsigned int ns_to_clocks(struct atmel_mci *host,
@@ -303,7 +386,7 @@ static inline unsigned int ns_to_clocks(struct atmel_mci *host,
}
static void atmci_set_timeout(struct atmel_mci *host,
- struct mmc_data *data)
+ struct atmel_mci_slot *slot, struct mmc_data *data)
{
static unsigned dtomul_to_shift[] = {
0, 4, 7, 8, 10, 12, 16, 20
@@ -326,7 +409,7 @@ static void atmci_set_timeout(struct atmel_mci *host,
dtocyc = 15;
}
- dev_vdbg(&host->mmc->class_dev, "setting timeout to %u cycles\n",
+ dev_vdbg(&slot->mmc->class_dev, "setting timeout to %u cycles\n",
dtocyc << dtomul_to_shift[dtomul]);
mci_writel(host, DTOR, (MCI_DTOMUL(dtomul) | MCI_DTOCYC(dtocyc)));
}
@@ -379,13 +462,12 @@ static u32 atmci_prepare_command(struct mmc_host *mmc,
}
static void atmci_start_command(struct atmel_mci *host,
- struct mmc_command *cmd,
- u32 cmd_flags)
+ struct mmc_command *cmd, u32 cmd_flags)
{
WARN_ON(host->cmd);
host->cmd = cmd;
- dev_vdbg(&host->mmc->class_dev,
+ dev_vdbg(&host->pdev->dev,
"start command: ARGR=0x%08x CMDR=0x%08x\n",
cmd->arg, cmd_flags);
@@ -393,34 +475,19 @@ static void atmci_start_command(struct atmel_mci *host,
mci_writel(host, CMDR, cmd_flags);
}
-static void send_stop_cmd(struct mmc_host *mmc, struct mmc_data *data)
+static void send_stop_cmd(struct atmel_mci *host, 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)
+static u32 atmci_submit_data(struct atmel_mci *host, struct mmc_data *data)
{
- struct atmel_mci *host = mmc_priv(mmc);
- u32 iflags;
+ u32 iflags;
data->error = -EINPROGRESS;
@@ -428,11 +495,6 @@ static u32 atmci_submit_data(struct mmc_host *mmc, struct mmc_data *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;
@@ -444,60 +506,57 @@ static u32 atmci_submit_data(struct mmc_host *mmc, struct mmc_data *data)
return iflags;
}
-static void atmci_request(struct mmc_host *mmc, struct mmc_request *mrq)
+static void atmci_start_request(struct atmel_mci *host,
+ struct atmel_mci_slot *slot)
{
- struct atmel_mci *host = mmc_priv(mmc);
- struct mmc_data *data;
+ struct mmc_request *mrq;
struct mmc_command *cmd;
+ struct mmc_data *data;
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;
- }
+ u32 cmdflags;
+ mrq = slot->mrq;
+ host->cur_slot = slot;
host->mrq = mrq;
+
host->pending_events = 0;
host->completed_events = 0;
- host->state = STATE_SENDING_CMD;
- atmci_enable(host);
+ mci_writel(host, CR, MCI_CR_MCIEN);
+ mci_writel(host, MR, slot->mode_reg);
+ mci_writel(host, SDCR, slot->sdc_reg);
+
+ iflags = mci_readl(host, IMR);
+ if (iflags)
+ dev_warn(&slot->mmc->class_dev, "WARNING: IMR=0x%08x\n",
+ iflags);
+
+ if (unlikely(test_and_clear_bit(ATMCI_CARD_NEED_INIT, &slot->flags))) {
+ /* Send init sequence (74 clock cycles) */
+ mci_writel(host, CMDR, MCI_CMDR_SPCMD_INIT);
+ while (!(mci_readl(host, SR) & MCI_CMDRDY))
+ cpu_relax();
+ }
- /* 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);
+ atmci_set_timeout(host, slot, data);
+ mci_writel(host, BLKR, MCI_BCNT(data->blocks)
+ | MCI_BLKLEN(data->blksz));
+ dev_vdbg(&slot->mmc->class_dev, "BLKR=0x%08x\n",
+ MCI_BCNT(data->blocks) | MCI_BLKLEN(data->blksz));
}
iflags = MCI_CMDRDY;
cmd = mrq->cmd;
- cmdflags = atmci_prepare_command(mmc, cmd);
+ cmdflags = atmci_prepare_command(slot->mmc, cmd);
atmci_start_command(host, cmd, cmdflags);
if (data)
- iflags |= atmci_submit_data(mmc, data);
+ iflags |= atmci_submit_data(host, data);
if (mrq->stop) {
- host->stop_cmdr = atmci_prepare_command(mmc, mrq->stop);
+ host->stop_cmdr = atmci_prepare_command(slot->mmc, mrq->stop);
host->stop_cmdr |= MCI_CMDR_STOP_XFER;
if (!(data->flags & MMC_DATA_WRITE))
host->stop_cmdr |= MCI_CMDR_TRDIR_READ;
@@ -514,19 +573,62 @@ static void atmci_request(struct mmc_host *mmc, struct mmc_request *mrq)
* prepared yet.)
*/
mci_writel(host, IER, iflags);
+}
- return;
+static void atmci_queue_request(struct atmel_mci *host,
+ struct atmel_mci_slot *slot, struct mmc_request *mrq)
+{
+ dev_vdbg(&slot->mmc->class_dev, "queue request: state=%d\n",
+ host->state);
-fail:
- atmci_disable(host);
- host->mrq = NULL;
- mrq->cmd->error = -EINVAL;
- mmc_request_done(mmc, mrq);
+ spin_lock_bh(&host->lock);
+ slot->mrq = mrq;
+ if (host->state == STATE_IDLE) {
+ host->state = STATE_SENDING_CMD;
+ clk_enable(host->mck);
+ atmci_start_request(host, slot);
+ } else {
+ list_add_tail(&slot->queue_node, &host->queue);
+ }
+ spin_unlock_bh(&host->lock);
+}
+
+static void atmci_request(struct mmc_host *mmc, struct mmc_request *mrq)
+{
+ struct atmel_mci_slot *slot = mmc_priv(mmc);
+ struct atmel_mci *host = slot->host;
+ struct mmc_data *data;
+
+ WARN_ON(slot->mrq);
+
+ /*
+ * 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 (!test_bit(ATMCI_CARD_PRESENT, &slot->flags)) {
+ mrq->cmd->error = -ENOMEDIUM;
+ mmc_request_done(mmc, mrq);
+ return;
+ }
+
+ /* We don't support multiple blocks of weird lengths. */
+ data = mrq->data;
+ if (data && data->blocks > 1 && data->blksz & 3) {
+ mrq->cmd->error = -EINVAL;
+ mmc_request_done(mmc, mrq);
+ }
+
+ atmci_queue_request(host, slot, mrq);
}
static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
{
- struct atmel_mci *host = mmc_priv(mmc);
+ struct atmel_mci_slot *slot = mmc_priv(mmc);
+ struct atmel_mci *host = slot->host;
if (ios->clock) {
u32 clkdiv;
@@ -540,28 +642,23 @@ static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
clkdiv = 255;
}
- host->mode_reg = MCI_MR_CLKDIV(clkdiv) | MCI_MR_WRPROOF
+ slot->mode_reg = MCI_MR_CLKDIV(clkdiv) | MCI_MR_WRPROOF
| MCI_MR_RDPROOF;
}
- host->sdc_reg &= ~MCI_SDCBUS_MASK;
+ slot->sdc_reg &= ~MCI_SDCBUS_MASK;
switch (ios->bus_width) {
case MMC_BUS_WIDTH_1:
- host->sdc_reg |= MCI_SDCBUS_1BIT;
+ slot->sdc_reg |= MCI_SDCBUS_1BIT;
break;
case MMC_BUS_WIDTH_4:
- host->sdc_reg |= MCI_SDCBUS_4BIT;
+ slot->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);
+ case MMC_POWER_UP:
+ set_bit(ATMCI_CARD_NEED_INIT, &slot->flags);
break;
default:
/*
@@ -575,28 +672,75 @@ static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
static int atmci_get_ro(struct mmc_host *mmc)
{
- int read_only = 0;
- struct atmel_mci *host = mmc_priv(mmc);
+ int read_only = -ENOSYS;
+ struct atmel_mci_slot *slot = mmc_priv(mmc);
- if (gpio_is_valid(host->wp_pin)) {
- read_only = gpio_get_value(host->wp_pin);
+ if (gpio_is_valid(slot->wp_pin)) {
+ read_only = gpio_get_value(slot->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 = {
+static int atmci_get_cd(struct mmc_host *mmc)
+{
+ int present = -ENOSYS;
+ struct atmel_mci_slot *slot = mmc_priv(mmc);
+
+ if (gpio_is_valid(slot->detect_pin)) {
+ present = !gpio_get_value(slot->detect_pin);
+ dev_dbg(&mmc->class_dev, "card is %spresent\n",
+ present ? "" : "not ");
+ }
+
+ return present;
+}
+
+static const struct mmc_host_ops atmci_ops = {
.request = atmci_request,
.set_ios = atmci_set_ios,
.get_ro = atmci_get_ro,
+ .get_cd = atmci_get_cd,
};
+/* Called with host->lock held */
+static void atmci_request_end(struct atmel_mci *host, struct mmc_request *mrq)
+ __releases(&host->lock)
+ __acquires(&host->lock)
+{
+ struct atmel_mci_slot *slot = NULL;
+ struct mmc_host *prev_mmc = host->cur_slot->mmc;
+
+ WARN_ON(host->cmd || host->data);
+
+ mci_writel(host, CR, MCI_CR_SWRST);
+
+ host->cur_slot->mrq = NULL;
+ host->mrq = NULL;
+ if (!list_empty(&host->queue)) {
+ slot = list_entry(host->queue.next,
+ struct atmel_mci_slot, queue_node);
+ list_del(&slot->queue_node);
+ dev_vdbg(&host->pdev->dev, "list not empty: %s is next\n",
+ mmc_hostname(slot->mmc));
+ host->state = STATE_SENDING_CMD;
+ atmci_start_request(host, slot);
+ } else {
+ dev_vdbg(&host->pdev->dev, "list empty, disabling clock\n");
+ /* Stall until write is complete, then disable the bus clock */
+ mci_readl(host, SR);
+ clk_disable(host->mck);
+
+ host->state = STATE_IDLE;
+ }
+
+ spin_unlock(&host->lock);
+ mmc_request_done(prev_mmc, mrq);
+ spin_lock(&host->lock);
+}
+
static void atmci_command_complete(struct atmel_mci *host,
struct mmc_command *cmd)
{
@@ -618,7 +762,7 @@ static void atmci_command_complete(struct atmel_mci *host,
cmd->error = 0;
if (cmd->error) {
- dev_dbg(&host->mmc->class_dev,
+ dev_dbg(&host->pdev->dev,
"command error: status=0x%08x\n", status);
if (cmd->data) {
@@ -632,81 +776,100 @@ static void atmci_command_complete(struct atmel_mci *host,
static void atmci_detect_change(unsigned long data)
{
- struct atmel_mci *host = (struct atmel_mci *)data;
- struct mmc_request *mrq = host->mrq;
- int present;
+ struct atmel_mci_slot *slot = (struct atmel_mci_slot *)data;
+ bool present;
+ bool present_old;
/*
- * atmci_remove() sets detect_pin to -1 before freeing the
- * interrupt. We must not re-enable the interrupt if it has
- * been freed.
+ * atmci_cleanup_slot() sets the ATMCI_SHUTDOWN flag before
+ * freeing the interrupt. We must not re-enable the interrupt
+ * if it has been freed, and if we're shutting down, it
+ * doesn't really matter whether the card is present or not.
*/
smp_rmb();
- if (!gpio_is_valid(host->detect_pin))
+ if (test_bit(ATMCI_SHUTDOWN, &slot->flags))
return;
- enable_irq(gpio_to_irq(host->detect_pin));
- present = !gpio_get_value(host->detect_pin);
+ enable_irq(gpio_to_irq(slot->detect_pin));
+ present = !gpio_get_value(slot->detect_pin);
+ present_old = test_bit(ATMCI_CARD_PRESENT, &slot->flags);
- dev_vdbg(&host->pdev->dev, "detect change: %d (was %d)\n",
- present, host->present);
+ dev_vdbg(&slot->mmc->class_dev, "detect change: %d (was %d)\n",
+ present, present_old);
- if (present != host->present) {
- dev_dbg(&host->mmc->class_dev, "card %s\n",
+ if (present != present_old) {
+ struct atmel_mci *host = slot->host;
+ struct mmc_request *mrq;
+
+ dev_dbg(&slot->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);
- }
+ spin_lock(&host->lock);
+
+ if (!present)
+ clear_bit(ATMCI_CARD_PRESENT, &slot->flags);
+ else
+ set_bit(ATMCI_CARD_PRESENT, &slot->flags);
/* Clean up queue if present */
+ mrq = slot->mrq;
if (mrq) {
- /*
- * Reset controller to terminate any ongoing
- * commands or data transfers.
- */
- mci_writel(host, CR, MCI_CR_SWRST);
- mci_readl(host, SR);
-
- host->data = NULL;
- host->cmd = NULL;
-
- switch (host->state) {
- case STATE_SENDING_CMD:
- mrq->cmd->error = -ENOMEDIUM;
- if (!mrq->data)
+ if (mrq == host->mrq) {
+ /*
+ * Reset controller to terminate any ongoing
+ * commands or data transfers.
+ */
+ mci_writel(host, CR, MCI_CR_SWRST);
+ mci_readl(host, SR);
+ host->data = NULL;
+ host->cmd = NULL;
+
+ switch (host->state) {
+ case STATE_IDLE:
break;
- /* fall through */
- case STATE_SENDING_DATA:
- mrq->data->error = -ENOMEDIUM;
- break;
- case STATE_DATA_BUSY:
- case STATE_DATA_ERROR:
- if (mrq->data->error == -EINPROGRESS)
+ case STATE_SENDING_CMD:
+ mrq->cmd->error = -ENOMEDIUM;
+ if (!mrq->data)
+ break;
+ /* fall through */
+ case STATE_SENDING_DATA:
mrq->data->error = -ENOMEDIUM;
- if (!mrq->stop)
break;
- /* fall through */
- case STATE_SENDING_STOP:
- mrq->stop->error = -ENOMEDIUM;
- break;
- }
+ case STATE_DATA_BUSY:
+ case STATE_DATA_ERROR:
+ if (mrq->data->error == -EINPROGRESS)
+ mrq->data->error = -ENOMEDIUM;
+ if (!mrq->stop)
+ break;
+ /* fall through */
+ case STATE_SENDING_STOP:
+ mrq->stop->error = -ENOMEDIUM;
+ break;
+ }
- atmci_request_end(host->mmc, mrq);
+ atmci_request_end(host, mrq);
+ } else {
+ list_del(&slot->queue_node);
+ mrq->cmd->error = -ENOMEDIUM;
+ if (mrq->data)
+ mrq->data->error = -ENOMEDIUM;
+ if (mrq->stop)
+ mrq->stop->error = -ENOMEDIUM;
+
+ spin_unlock(&host->lock);
+ mmc_request_done(slot->mmc, mrq);
+ spin_lock(&host->lock);
+ }
}
+ spin_unlock(&host->lock);
- mmc_detect_change(host->mmc, 0);
+ mmc_detect_change(slot->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 atmel_mci *host = (struct atmel_mci *)priv;
struct mmc_request *mrq = host->mrq;
struct mmc_data *data = host->data;
struct mmc_command *cmd = host->cmd;
@@ -714,9 +877,11 @@ static void atmci_tasklet_func(unsigned long priv)
enum atmel_mci_state prev_state;
u32 status;
+ spin_lock(&host->lock);
+
state = host->state;
- dev_vdbg(&mmc->class_dev,
+ dev_vdbg(&host->pdev->dev,
"tasklet: state %u pending/completed/mask %lx/%lx/%x\n",
state, host->pending_events, host->completed_events,
mci_readl(host, IMR));
@@ -725,6 +890,9 @@ static void atmci_tasklet_func(unsigned long priv)
prev_state = state;
switch (state) {
+ case STATE_IDLE:
+ break;
+
case STATE_SENDING_CMD:
if (!atmci_test_and_clear_pending(host,
EVENT_CMD_COMPLETE))
@@ -734,8 +902,8 @@ static void atmci_tasklet_func(unsigned long priv)
atmci_set_completed(host, EVENT_CMD_COMPLETE);
atmci_command_complete(host, mrq->cmd);
if (!mrq->data || cmd->error) {
- atmci_request_end(mmc, host->mrq);
- break;
+ atmci_request_end(host, host->mrq);
+ goto unlock;
}
prev_state = state = STATE_SENDING_DATA;
@@ -745,7 +913,7 @@ static void atmci_tasklet_func(unsigned long priv)
if (atmci_test_and_clear_pending(host,
EVENT_DATA_ERROR)) {
if (data->stop)
- send_stop_cmd(host->mmc, data);
+ send_stop_cmd(host, data);
state = STATE_DATA_ERROR;
break;
}
@@ -768,15 +936,15 @@ static void atmci_tasklet_func(unsigned long priv)
status = host->data_status;
if (unlikely(status & ATMCI_DATA_ERROR_FLAGS)) {
if (status & MCI_DTOE) {
- dev_dbg(&mmc->class_dev,
+ dev_dbg(&host->pdev->dev,
"data timeout error\n");
data->error = -ETIMEDOUT;
} else if (status & MCI_DCRCE) {
- dev_dbg(&mmc->class_dev,
+ dev_dbg(&host->pdev->dev,
"data CRC error\n");
data->error = -EILSEQ;
} else {
- dev_dbg(&mmc->class_dev,
+ dev_dbg(&host->pdev->dev,
"data FIFO error (status=%08x)\n",
status);
data->error = -EIO;
@@ -787,14 +955,13 @@ static void atmci_tasklet_func(unsigned long priv)
}
if (!data->stop) {
- atmci_request_end(mmc, host->mrq);
- prev_state = state;
- break;
+ atmci_request_end(host, host->mrq);
+ goto unlock;
}
prev_state = state = STATE_SENDING_STOP;
if (!data->error)
- send_stop_cmd(host->mmc, data);
+ send_stop_cmd(host, data);
/* fall through */
case STATE_SENDING_STOP:
@@ -804,9 +971,8 @@ static void atmci_tasklet_func(unsigned long priv)
host->cmd = NULL;
atmci_command_complete(host, mrq->stop);
- atmci_request_end(mmc, host->mrq);
- prev_state = state;
- break;
+ atmci_request_end(host, host->mrq);
+ goto unlock;
case STATE_DATA_ERROR:
if (!atmci_test_and_clear_pending(host,
@@ -819,6 +985,9 @@ static void atmci_tasklet_func(unsigned long priv)
} while (state != prev_state);
host->state = state;
+
+unlock:
+ spin_unlock(&host->lock);
}
static void atmci_read_data_pio(struct atmel_mci *host)
@@ -868,9 +1037,11 @@ static void atmci_read_data_pio(struct atmel_mci *host)
mci_writel(host, IDR, (MCI_NOTBUSY | MCI_RXRDY
| ATMCI_DATA_ERROR_FLAGS));
host->data_status = status;
+ data->bytes_xfered += nbytes;
+ smp_wmb();
atmci_set_pending(host, EVENT_DATA_ERROR);
tasklet_schedule(&host->tasklet);
- break;
+ return;
}
} while (status & MCI_RXRDY);
@@ -883,6 +1054,7 @@ done:
mci_writel(host, IDR, MCI_RXRDY);
mci_writel(host, IER, MCI_NOTBUSY);
data->bytes_xfered += nbytes;
+ smp_wmb();
atmci_set_pending(host, EVENT_XFER_COMPLETE);
}
@@ -936,9 +1108,11 @@ static void atmci_write_data_pio(struct atmel_mci *host)
mci_writel(host, IDR, (MCI_NOTBUSY | MCI_TXRDY
| ATMCI_DATA_ERROR_FLAGS));
host->data_status = status;
+ data->bytes_xfered += nbytes;
+ smp_wmb();
atmci_set_pending(host, EVENT_DATA_ERROR);
tasklet_schedule(&host->tasklet);
- break;
+ return;
}
} while (status & MCI_TXRDY);
@@ -951,29 +1125,26 @@ done:
mci_writel(host, IDR, MCI_TXRDY);
mci_writel(host, IER, MCI_NOTBUSY);
data->bytes_xfered += nbytes;
+ smp_wmb();
atmci_set_pending(host, EVENT_XFER_COMPLETE);
}
-static void atmci_cmd_interrupt(struct mmc_host *mmc, u32 status)
+static void atmci_cmd_interrupt(struct atmel_mci *host, u32 status)
{
- struct atmel_mci *host = mmc_priv(mmc);
-
mci_writel(host, IDR, MCI_CMDRDY);
host->cmd_status = status;
+ smp_wmb();
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);
+ struct atmel_mci *host = dev_id;
u32 status, mask, pending;
unsigned int pass_count = 0;
- spin_lock(&mmc->lock);
-
do {
status = mci_readl(host, SR);
mask = mci_readl(host, IMR);
@@ -985,7 +1156,9 @@ static irqreturn_t atmci_interrupt(int irq, void *dev_id)
mci_writel(host, IDR, ATMCI_DATA_ERROR_FLAGS
| MCI_RXRDY | MCI_TXRDY);
pending &= mci_readl(host, IMR);
+
host->data_status = status;
+ smp_wmb();
atmci_set_pending(host, EVENT_DATA_ERROR);
tasklet_schedule(&host->tasklet);
}
@@ -993,6 +1166,7 @@ static irqreturn_t atmci_interrupt(int irq, void *dev_id)
mci_writel(host, IDR,
ATMCI_DATA_ERROR_FLAGS | MCI_NOTBUSY);
host->data_status = status;
+ smp_wmb();
atmci_set_pending(host, EVENT_DATA_COMPLETE);
tasklet_schedule(&host->tasklet);
}
@@ -1002,18 +1176,15 @@ static irqreturn_t atmci_interrupt(int irq, void *dev_id)
atmci_write_data_pio(host);
if (pending & MCI_CMDRDY)
- atmci_cmd_interrupt(mmc, status);
+ atmci_cmd_interrupt(host, 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);
+ struct atmel_mci_slot *slot = dev_id;
/*
* Disable interrupts until the pin has stabilized and check
@@ -1021,21 +1192,120 @@ static irqreturn_t atmci_detect_interrupt(int irq, void *dev_id)
* middle of the timer routine when this interrupt triggers.
*/
disable_irq_nosync(irq);
- mod_timer(&host->detect_timer, jiffies + msecs_to_jiffies(20));
+ mod_timer(&slot->detect_timer, jiffies + msecs_to_jiffies(20));
return IRQ_HANDLED;
}
+static int __init atmci_init_slot(struct atmel_mci *host,
+ struct mci_slot_pdata *slot_data, u32 sdc_reg)
+{
+ struct mmc_host *mmc;
+ struct atmel_mci_slot *slot;
+
+ mmc = mmc_alloc_host(sizeof(struct atmel_mci_slot), &host->pdev->dev);
+ if (!mmc)
+ return -ENOMEM;
+
+ slot = mmc_priv(mmc);
+ slot->mmc = mmc;
+ slot->host = host;
+ slot->detect_pin = slot_data->detect_pin;
+ slot->wp_pin = slot_data->wp_pin;
+ slot->sdc_reg = sdc_reg;
+
+ mmc->ops = &atmci_ops;
+ mmc->f_min = DIV_ROUND_UP(host->bus_hz, 512);
+ mmc->f_max = host->bus_hz / 2;
+ mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
+ if (slot_data->bus_width >= 4)
+ 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;
+
+ /* Assume card is present initially */
+ set_bit(ATMCI_CARD_PRESENT, &slot->flags);
+ if (gpio_is_valid(slot->detect_pin)) {
+ if (gpio_request(slot->detect_pin, "mmc_detect")) {
+ dev_dbg(&mmc->class_dev, "no detect pin available\n");
+ slot->detect_pin = -EBUSY;
+ } else if (gpio_get_value(slot->detect_pin)) {
+ clear_bit(ATMCI_CARD_PRESENT, &slot->flags);
+ }
+ }
+
+ if (!gpio_is_valid(slot->detect_pin))
+ mmc->caps |= MMC_CAP_NEEDS_POLL;
+
+ if (gpio_is_valid(slot->wp_pin)) {
+ if (gpio_request(slot->wp_pin, "mmc_wp")) {
+ dev_dbg(&mmc->class_dev, "no WP pin available\n");
+ slot->wp_pin = -EBUSY;
+ }
+ }
+
+ mmc_add_host(mmc);
+
+ if (gpio_is_valid(slot->detect_pin)) {
+ int ret;
+
+ setup_timer(&slot->detect_timer, atmci_detect_change,
+ (unsigned long)slot);
+
+ ret = request_irq(gpio_to_irq(slot->detect_pin),
+ atmci_detect_interrupt,
+ IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
+ "mmc-detect", slot);
+ if (ret) {
+ dev_dbg(&mmc->class_dev,
+ "could not request IRQ %d for detect pin\n",
+ gpio_to_irq(slot->detect_pin));
+ gpio_free(slot->detect_pin);
+ slot->detect_pin = -EBUSY;
+ }
+ }
+
+ list_add_tail(&slot->slot_node, &host->slots);
+
+ atmci_init_debugfs(slot);
+
+ return 0;
+}
+
+static void __exit atmci_cleanup_slot(struct atmel_mci_slot *slot)
+{
+ /* Debugfs stuff is cleaned up by mmc core */
+
+ set_bit(ATMCI_SHUTDOWN, &slot->flags);
+ smp_wmb();
+
+ mmc_remove_host(slot->mmc);
+
+ if (gpio_is_valid(slot->detect_pin)) {
+ int pin = slot->detect_pin;
+
+ free_irq(gpio_to_irq(pin), slot);
+ del_timer_sync(&slot->detect_timer);
+ gpio_free(pin);
+ }
+ if (gpio_is_valid(slot->wp_pin))
+ gpio_free(slot->wp_pin);
+
+ list_del(&slot->slot_node);
+ mmc_free_host(slot->mmc);
+}
+
static int __init atmci_probe(struct platform_device *pdev)
{
struct mci_platform_data *pdata;
- struct mci_slot_pdata *slot;
- struct atmel_mci *host;
- struct mmc_host *mmc;
- struct resource *regs;
- u32 sdc_reg;
- int irq;
- int ret;
+ struct atmel_mci *host;
+ struct resource *regs;
+ int irq;
+ int ret;
regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!regs)
@@ -1047,27 +1317,14 @@ static int __init atmci_probe(struct platform_device *pdev)
if (irq < 0)
return irq;
- /* TODO: Allow using several slots at once */
- if (pdata->slot[0].bus_width) {
- sdc_reg = MCI_SDCSEL_SLOT_A;
- slot = &pdata->slot[0];
- } else if (pdata->slot[1].bus_width) {
- sdc_reg = MCI_SDCSEL_SLOT_B;
- slot = &pdata->slot[1];
- } else {
- return -EINVAL;
- }
-
- mmc = mmc_alloc_host(sizeof(struct atmel_mci), &pdev->dev);
- if (!mmc)
+ host = kzalloc(sizeof(struct atmel_mci), GFP_KERNEL);
+ if (!host)
return -ENOMEM;
- host = mmc_priv(mmc);
host->pdev = pdev;
- host->mmc = mmc;
- host->detect_pin = slot->detect_pin;
- host->wp_pin = slot->wp_pin;
- host->sdc_reg = sdc_reg;
+ spin_lock_init(&host->lock);
+ INIT_LIST_HEAD(&host->queue);
+ INIT_LIST_HEAD(&host->slots);
host->mck = clk_get(&pdev->dev, "mci_clk");
if (IS_ERR(host->mck)) {
@@ -1087,123 +1344,65 @@ static int __init atmci_probe(struct platform_device *pdev)
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;
- if (slot->bus_width >= 4)
- 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)host);
- tasklet_init(&host->tasklet, atmci_tasklet_func, (unsigned long)mmc);
-
- ret = request_irq(irq, atmci_interrupt, 0, pdev->dev.bus_id, mmc);
+ ret = request_irq(irq, atmci_interrupt, 0, pdev->dev.bus_id, host);
if (ret)
goto err_request_irq;
- /* Assume card is present if we don't have a detect pin */
- host->present = 1;
- if (gpio_is_valid(host->detect_pin)) {
- 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 (!gpio_is_valid(host->detect_pin))
- mmc->caps |= MMC_CAP_NEEDS_POLL;
-
- if (gpio_is_valid(host->wp_pin)) {
- 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 (gpio_is_valid(host->detect_pin)) {
- 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;
- }
+ /* We need at least one slot to succeed */
+ ret = -1;
+ if (pdata->slot[0].bus_width)
+ ret &= atmci_init_slot(host, &pdata->slot[0],
+ MCI_SDCSEL_SLOT_A);
+ if (pdata->slot[1].bus_width)
+ ret &= atmci_init_slot(host, &pdata->slot[1],
+ MCI_SDCSEL_SLOT_B);
+ if (ret) {
+ ret = -ENODEV;
+ goto err_init_slot;
}
- dev_info(&mmc->class_dev,
- "Atmel MCI controller at 0x%08lx irq %d\n",
+ dev_info(&pdev->dev, "Atmel MCI controller at 0x%08lx irq %d\n",
host->mapbase, irq);
- atmci_init_debugfs(host);
-
return 0;
+err_init_slot:
+ free_irq(irq, host);
err_request_irq:
iounmap(host->regs);
err_ioremap:
clk_put(host->mck);
err_clk_get:
- mmc_free_host(mmc);
+ kfree(host);
return ret;
}
static int __exit atmci_remove(struct platform_device *pdev)
{
- struct atmel_mci *host = platform_get_drvdata(pdev);
+ struct atmel_mci *host = platform_get_drvdata(pdev);
+ struct atmel_mci_slot *slot, *_slot;
platform_set_drvdata(pdev, NULL);
- if (host) {
- /* Debugfs stuff is cleaned up by mmc core */
-
- if (gpio_is_valid(host->detect_pin)) {
- 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);
+ list_for_each_entry_safe(slot, _slot, &host->slots, slot_node)
+ atmci_cleanup_slot(slot);
- if (gpio_is_valid(host->wp_pin))
- gpio_free(host->wp_pin);
+ clk_enable(host->mck);
+ mci_writel(host, IDR, ~0UL);
+ mci_writel(host, CR, MCI_CR_MCIDIS);
+ mci_readl(host, SR);
+ clk_disable(host->mck);
- free_irq(platform_get_irq(pdev, 0), host->mmc);
- iounmap(host->regs);
+ free_irq(platform_get_irq(pdev, 0), host);
+ iounmap(host->regs);
- clk_put(host->mck);
+ clk_put(host->mck);
+ kfree(host);
- mmc_free_host(host->mmc);
- }
return 0;
}
--
1.5.6.5
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