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diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
index eeac479..7913cd8 100644
--- a/drivers/mmc/host/atmel-mci.c
+++ b/drivers/mmc/host/atmel-mci.c
@@ -39,7 +39,6 @@ enum {
EVENT_STOP_COMPLETE,
EVENT_DMA_COMPLETE,
EVENT_DMA_ERROR,
- EVENT_CARD_DETECT,
};
struct atmel_mci_dma {
@@ -70,6 +69,9 @@ struct atmel_mci {
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;
@@ -108,8 +110,6 @@ MODULE_PARM_DESC(fmax, "Max frequency in Hz of the MMC bus clock");
test_bit(EVENT_DMA_COMPLETE, &host->completed_events)
#define mci_dma_error_is_complete(host) \
test_bit(EVENT_DMA_ERROR, &host->completed_events)
-#define mci_card_detect_is_complete(host) \
- test_bit(EVENT_CARD_DETECT, &host->completed_events)
/* Test and clear bit macros for pending events */
#define mci_clear_cmd_is_pending(host) \
@@ -124,8 +124,6 @@ MODULE_PARM_DESC(fmax, "Max frequency in Hz of the MMC bus clock");
test_and_clear_bit(EVENT_STOP_COMPLETE, &host->pending_events)
#define mci_clear_dma_error_is_pending(host) \
test_and_clear_bit(EVENT_DMA_ERROR, &host->pending_events)
-#define mci_clear_card_detect_is_pending(host) \
- test_and_clear_bit(EVENT_CARD_DETECT, &host->pending_events)
/* Test and set bit macros for completed events */
#define mci_set_cmd_is_completed(host) \
@@ -140,8 +138,6 @@ MODULE_PARM_DESC(fmax, "Max frequency in Hz of the MMC bus clock");
test_and_set_bit(EVENT_STOP_COMPLETE, &host->completed_events)
#define mci_set_dma_error_is_completed(host) \
test_and_set_bit(EVENT_DMA_ERROR, &host->completed_events)
-#define mci_set_card_detect_is_completed(host) \
- test_and_set_bit(EVENT_CARD_DETECT, &host->completed_events)
/* Set bit macros for completed events */
#define mci_set_cmd_complete(host) \
@@ -158,8 +154,6 @@ MODULE_PARM_DESC(fmax, "Max frequency in Hz of the MMC bus clock");
set_bit(EVENT_DMA_COMPLETE, &host->completed_events)
#define mci_set_dma_error_complete(host) \
set_bit(EVENT_DMA_ERROR, &host->completed_events)
-#define mci_set_card_detect_complete(host) \
- set_bit(EVENT_CARD_DETECT, &host->completed_events)
/* Set bit macros for pending events */
#define mci_set_cmd_pending(host) \
@@ -174,8 +168,6 @@ MODULE_PARM_DESC(fmax, "Max frequency in Hz of the MMC bus clock");
set_bit(EVENT_STOP_COMPLETE, &host->pending_events)
#define mci_set_dma_error_pending(host) \
set_bit(EVENT_DMA_ERROR, &host->pending_events)
-#define mci_set_card_detect_pending(host) \
- set_bit(EVENT_CARD_DETECT, &host->pending_events)
/* Clear bit macros for pending events */
#define mci_clear_cmd_pending(host) \
@@ -190,8 +182,6 @@ MODULE_PARM_DESC(fmax, "Max frequency in Hz of the MMC bus clock");
clear_bit(EVENT_STOP_COMPLETE, &host->pending_events)
#define mci_clear_dma_error_pending(host) \
clear_bit(EVENT_DMA_ERROR, &host->pending_events)
-#define mci_clear_card_detect_pending(host) \
- clear_bit(EVENT_CARD_DETECT, &host->pending_events)
#ifdef CONFIG_DEBUG_FS
@@ -560,6 +550,21 @@ static void atmci_request(struct mmc_host *mmc, struct mmc_request *mrq)
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;
@@ -729,6 +734,61 @@ 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;
+
+ /*
+ * 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_BIT(SWRST));
+ mci_writel(host, IDR, ~0UL);
+ mci_writel(host, CR, MCI_BIT(MCIEN));
+ }
+
+ /* Clean up queue if present */
+ if (mrq) {
+ if (!mci_cmd_is_complete(host))
+ mrq->cmd->error = -ENOMEDIUM;
+ if (mrq->data && !mci_data_is_complete(host)
+ && !mci_data_error_is_complete(host)) {
+ dma_stop_request(host->dma.req.req.dmac,
+ host->dma.req.req.channel);
+ host->data->error = -ENOMEDIUM;
+ atmci_data_complete(host, host->data);
+ }
+ if (mrq->stop && !mci_stop_is_complete(host))
+ 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;
@@ -806,33 +866,6 @@ static void atmci_tasklet_func(unsigned long priv)
data->bytes_xfered = data->blocks * data->blksz;
atmci_data_complete(host, data);
}
- if (mci_clear_card_detect_is_pending(host)) {
- /* Reset controller if card is gone */
- if (!host->present) {
- mci_writel(host, CR, MCI_BIT(SWRST));
- mci_writel(host, IDR, ~0UL);
- mci_writel(host, CR, MCI_BIT(MCIEN));
- }
-
- /* Clean up queue if present */
- if (mrq) {
- if (!mci_cmd_is_complete(host))
- mrq->cmd->error = -ETIMEDOUT;
- if (mrq->data && !mci_data_is_complete(host)
- && !mci_data_error_is_complete(host)) {
- dma_stop_request(host->dma.req.req.dmac,
- host->dma.req.req.channel);
- host->data->error = -ETIMEDOUT;
- atmci_data_complete(host, data);
- }
- if (mrq->stop && !mci_stop_is_complete(host))
- mrq->stop->error = -ETIMEDOUT;
-
- host->cmd = NULL;
- atmci_request_end(mmc, mrq);
- }
- mmc_detect_change(host->mmc, msecs_to_jiffies(100));
- }
}
static void atmci_cmd_interrupt(struct mmc_host *mmc, u32 status)
@@ -957,20 +990,19 @@ static irqreturn_t atmci_interrupt(int irq, void *dev_id)
return IRQ_HANDLED;
}
-static irqreturn_t atmci_detect_change(int irq, void *dev_id)
+static irqreturn_t atmci_detect_interrupt(int irq, void *dev_id)
{
struct mmc_host *mmc = dev_id;
struct atmel_mci *host = mmc_priv(mmc);
- int present = !gpio_get_value(irq_to_gpio(irq));
+ /*
+ * 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));
- if (present != host->present) {
- dev_dbg(&mmc->class_dev, "card %s\n",
- present ? "inserted" : "removed");
- host->present = present;
- mci_set_card_detect_pending(host);
- tasklet_schedule(&host->tasklet);
- }
return IRQ_HANDLED;
}
@@ -1079,8 +1111,11 @@ static int __devinit atmci_probe(struct platform_device *pdev)
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_change,
+ atmci_detect_interrupt,
IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
DRIVER_NAME, mmc);
if (ret) {
@@ -1125,9 +1160,16 @@ static int __devexit atmci_remove(struct platform_device *pdev)
atmci_cleanup_debugfs(host);
if (host->detect_pin >= 0) {
- free_irq(gpio_to_irq(host->detect_pin), host->mmc);
+ int pin = host->detect_pin;
+
+ /* Make sure our 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);
cancel_delayed_work(&host->mmc->detect);
- gpio_free(host->detect_pin);
+ gpio_free(pin);
}
mmc_remove_host(host->mmc);
|