2 files changed, 156 insertions, 10 deletions

diff --git a/drivers/mmc/host/s3cmci.c b/drivers/mmc/host/s3cmci.c
index 8c2c8b456087..7660ac4572e5 100644
--- a/drivers/mmc/host/s3cmci.c
+++ b/drivers/mmc/host/s3cmci.c
@@ -190,7 +190,33 @@ static inline u32 disable_imask(struct s3cmci_host *host, u32 imask)
 
 static inline void clear_imask(struct s3cmci_host *host)
 {
-        writel(0, host->base + host->sdiimsk);
+        u32 mask = readl(host->base + host->sdiimsk);
+
+        /* preserve the SDIO IRQ mask state */
+        mask &= S3C2410_SDIIMSK_SDIOIRQ;
+        writel(mask, host->base + host->sdiimsk);
+}
+
+/**
+ * s3cmci_check_sdio_irq - test whether the SDIO IRQ is being signalled
+ * @host: The host to check.
+ *
+ * Test to see if the SDIO interrupt is being signalled in case the
+ * controller has failed to re-detect a card interrupt. Read GPE8 and
+ * see if it is low and if so, signal a SDIO interrupt.
+ *
+ * This is currently called if a request is finished (we assume that the
+ * bus is now idle) and when the SDIO IRQ is enabled in case the IRQ is
+ * already being indicated.
+*/
+static void s3cmci_check_sdio_irq(struct s3cmci_host *host)
+{
+        if (host->sdio_irqen) {
+                if (gpio_get_value(S3C2410_GPE(8)) == 0) {
+                        printk(KERN_DEBUG "%s: signalling irq\n", __func__);
+                        mmc_signal_sdio_irq(host->mmc);
+                }
+        }
 }
 
 static inline int get_data_buffer(struct s3cmci_host *host,
@@ -238,6 +264,64 @@ static inline u32 fifo_free(struct s3cmci_host *host)
         return 63 - fifostat;
 }
 
+/**
+ * s3cmci_enable_irq - enable IRQ, after having disabled it.
+ * @host: The device state.
+ * @more: True if more IRQs are expected from transfer.
+ *
+ * Enable the main IRQ if needed after it has been disabled.
+ *
+ * The IRQ can be one of the following states:
+ *      - disabled during IDLE
+ *      - disabled whilst processing data
+ *      - enabled during transfer
+ *      - enabled whilst awaiting SDIO interrupt detection
+ */
+static void s3cmci_enable_irq(struct s3cmci_host *host, bool more)
+{
+        unsigned long flags;
+        bool enable = false;
+
+        local_irq_save(flags);
+
+        host->irq_enabled = more;
+        host->irq_disabled = false;
+
+        enable = more | host->sdio_irqen;
+
+        if (host->irq_state != enable) {
+                host->irq_state = enable;
+
+                if (enable)
+                        enable_irq(host->irq);
+                else
+                        disable_irq(host->irq);
+        }
+
+        local_irq_restore(flags);
+}
+
+/**
+ *
+ */
+static void s3cmci_disable_irq(struct s3cmci_host *host, bool transfer)
+{
+        unsigned long flags;
+
+        local_irq_save(flags);
+
+        //printk(KERN_DEBUG "%s: transfer %d\n", __func__, transfer);
+
+        host->irq_disabled = transfer;
+
+        if (transfer && host->irq_state) {
+                host->irq_state = false;
+                disable_irq(host->irq);
+        }
+
+        local_irq_restore(flags);
+}
+
 static void do_pio_read(struct s3cmci_host *host)
 {
         int res;
@@ -374,8 +458,7 @@ static void pio_tasklet(unsigned long data)
 {
         struct s3cmci_host *host = (struct s3cmci_host *) data;
 
-
-        disable_irq(host->irq);
+        s3cmci_disable_irq(host, true);
 
         if (host->pio_active == XFER_WRITE)
                 do_pio_write(host);
@@ -395,9 +478,10 @@ static void pio_tasklet(unsigned long data)
                                 host->mrq->data->error = -EINVAL;
                 }
 
+                s3cmci_enable_irq(host, false);
                 finalize_request(host);
         } else
-                enable_irq(host->irq);
+                s3cmci_enable_irq(host, true);
 }
 
 /*
@@ -432,17 +516,27 @@ static irqreturn_t s3cmci_irq(int irq, void *dev_id)
         struct s3cmci_host *host = dev_id;
         struct mmc_command *cmd;
         u32 mci_csta, mci_dsta, mci_fsta, mci_dcnt, mci_imsk;
-        u32 mci_cclear, mci_dclear;
+        u32 mci_cclear = 0, mci_dclear;
         unsigned long iflags;
 
+        mci_dsta = readl(host->base + S3C2410_SDIDSTA);
+        mci_imsk = readl(host->base + host->sdiimsk);
+
+        if (mci_dsta & S3C2410_SDIDSTA_SDIOIRQDETECT) {
+                if (mci_imsk & S3C2410_SDIIMSK_SDIOIRQ) {
+                        mci_dclear = S3C2410_SDIDSTA_SDIOIRQDETECT;
+                        writel(mci_dclear, host->base + S3C2410_SDIDSTA);
+
+                        mmc_signal_sdio_irq(host->mmc);
+                        return IRQ_HANDLED;
+                }
+        }
+
         spin_lock_irqsave(&host->complete_lock, iflags);
 
         mci_csta = readl(host->base + S3C2410_SDICMDSTAT);
-        mci_dsta = readl(host->base + S3C2410_SDIDSTA);
         mci_dcnt = readl(host->base + S3C2410_SDIDCNT);
         mci_fsta = readl(host->base + S3C2410_SDIFSTA);
-        mci_imsk = readl(host->base + host->sdiimsk);
-        mci_cclear = 0;
         mci_dclear = 0;
 
         if ((host->complete_what == COMPLETION_NONE) ||
@@ -776,6 +870,8 @@ static void finalize_request(struct s3cmci_host *host)
 request_done:
         host->complete_what = COMPLETION_NONE;
         host->mrq = NULL;
+
+        s3cmci_check_sdio_irq(host);
         mmc_request_done(host->mmc, mrq);
 }
 
@@ -1037,7 +1133,7 @@ static void s3cmci_send_request(struct mmc_host *mmc)
         s3cmci_send_command(host, cmd);
 
         /* Enable Interrupt */
-        enable_irq(host->irq);
+        s3cmci_enable_irq(host, true);
 }
 
 static int s3cmci_card_present(struct mmc_host *mmc)
@@ -1178,11 +1274,52 @@ static int s3cmci_get_ro(struct mmc_host *mmc)
         return ret;
 }
 
+static void s3cmci_enable_sdio_irq(struct mmc_host *mmc, int enable)
+{
+        struct s3cmci_host *host = mmc_priv(mmc);
+        unsigned long flags;
+        u32 con;
+
+        local_irq_save(flags);
+
+        con = readl(host->base + S3C2410_SDICON);
+        host->sdio_irqen = enable;
+
+        if (enable == host->sdio_irqen)
+                goto same_state;
+
+        if (enable) {
+                con |= S3C2410_SDICON_SDIOIRQ;
+                enable_imask(host, S3C2410_SDIIMSK_SDIOIRQ);
+
+                if (!host->irq_state && !host->irq_disabled) {
+                        host->irq_state = true;
+                        enable_irq(host->irq);
+                }
+        } else {
+                disable_imask(host, S3C2410_SDIIMSK_SDIOIRQ);
+                con &= ~S3C2410_SDICON_SDIOIRQ;
+
+                if (!host->irq_enabled && host->irq_state) {
+                        disable_irq_nosync(host->irq);
+                        host->irq_state = false;
+                }
+        }
+
+        writel(con, host->base + S3C2410_SDICON);
+
+ same_state:
+        local_irq_restore(flags);
+
+        s3cmci_check_sdio_irq(host);
+}
+
 static struct mmc_host_ops s3cmci_ops = {
         .request        = s3cmci_request,
         .set_ios        = s3cmci_set_ios,
         .get_ro         = s3cmci_get_ro,
         .get_cd         = s3cmci_card_present,
+        .enable_sdio_irq = s3cmci_enable_sdio_irq,
 };
 
 static struct s3c24xx_mci_pdata s3cmci_def_pdata = {
@@ -1257,6 +1394,9 @@ static int s3cmci_state_show(struct seq_file *seq, void *v)
         seq_printf(seq, "Prescale = %d\n", host->prescaler);
         seq_printf(seq, "is2440 = %d\n", host->is2440);
         seq_printf(seq, "IRQ = %d\n", host->irq);
+        seq_printf(seq, "IRQ enabled = %d\n", host->irq_enabled);
+        seq_printf(seq, "IRQ disabled = %d\n", host->irq_disabled);
+        seq_printf(seq, "IRQ state = %d\n", host->irq_state);
         seq_printf(seq, "CD IRQ = %d\n", host->irq_cd);
         seq_printf(seq, "Do DMA = %d\n", host->dodma);
         seq_printf(seq, "SDIIMSK at %d\n", host->sdiimsk);
@@ -1468,6 +1608,7 @@ static int __devinit s3cmci_probe(struct platform_device *pdev)
          * ensure we don't lock the system with un-serviceable requests. */
 
         disable_irq(host->irq);
+        host->irq_state = false;
 
         if (host->pdata->gpio_detect) {
                 ret = gpio_request(host->pdata->gpio_detect, "s3cmci detect");
@@ -1526,7 +1667,7 @@ static int __devinit s3cmci_probe(struct platform_device *pdev)
 
         mmc->ops        = &s3cmci_ops;
         mmc->ocr_avail  = MMC_VDD_32_33 | MMC_VDD_33_34;
-        mmc->caps       = MMC_CAP_4_BIT_DATA;
+        mmc->caps       = MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
         mmc->f_min      = host->clk_rate / (host->clk_div * 256);
         mmc->f_max      = host->clk_rate / host->clk_div;
 
diff --git a/drivers/mmc/host/s3cmci.h b/drivers/mmc/host/s3cmci.h
index fc96194a06f4..62fac6602306 100644
--- a/drivers/mmc/host/s3cmci.h
+++ b/drivers/mmc/host/s3cmci.h
@@ -42,6 +42,11 @@ struct s3cmci_host {
         int                     dodma;
         int                     dmatogo;
 
+        bool                    irq_disabled;
+        bool                    irq_enabled;
+        bool                    irq_state;
+        int                     sdio_irqen;
+
         struct mmc_request      *mrq;
         int                     cmd_is_stop;