1 files changed, 48 insertions, 0 deletions

diff --git a/drivers/mmc/host/at91_mci.c b/drivers/mmc/host/at91_mci.c
index fce171c7c67e..e9242110ce2e 100644
--- a/drivers/mmc/host/at91_mci.c
+++ b/drivers/mmc/host/at91_mci.c
@@ -130,6 +130,43 @@ struct at91mci_host
         struct timer_list timer;
 };
 
+/*
+ * Reset the controller and restore most of the state
+ */
+static void at91_reset_host(struct at91mci_host *host)
+{
+        unsigned long flags;
+        u32 mr;
+        u32 sdcr;
+        u32 dtor;
+        u32 imr;
+
+        local_irq_save(flags);
+        imr = at91_mci_read(host, AT91_MCI_IMR);
+
+        at91_mci_write(host, AT91_MCI_IDR, 0xffffffff);
+
+        /* save current state */
+        mr = at91_mci_read(host, AT91_MCI_MR) & 0x7fff;
+        sdcr = at91_mci_read(host, AT91_MCI_SDCR);
+        dtor = at91_mci_read(host, AT91_MCI_DTOR);
+
+        /* reset the controller */
+        at91_mci_write(host, AT91_MCI_CR, AT91_MCI_MCIDIS | AT91_MCI_SWRST);
+
+        /* restore state */
+        at91_mci_write(host, AT91_MCI_CR, AT91_MCI_MCIEN);
+        at91_mci_write(host, AT91_MCI_MR, mr);
+        at91_mci_write(host, AT91_MCI_SDCR, sdcr);
+        at91_mci_write(host, AT91_MCI_DTOR, dtor);
+        at91_mci_write(host, AT91_MCI_IER, imr);
+
+        /* make sure sdio interrupts will fire */
+        at91_mci_read(host, AT91_MCI_SR);
+
+        local_irq_restore(flags);
+}
+
 static void at91_timeout_timer(unsigned long data)
 {
         struct at91mci_host *host;
@@ -148,6 +185,7 @@ static void at91_timeout_timer(unsigned long data)
                                 host->request->cmd->error = -ETIMEDOUT;
                 }
 
+                at91_reset_host(host);
                 mmc_request_done(host->mmc, host->request);
         }
 }
@@ -512,6 +550,11 @@ static void at91_mci_send_command(struct at91mci_host *host, struct mmc_command
                 mr |= AT91_MCI_PDCMODE;
                 at91_mci_write(host, AT91_MCI_MR, mr);
 
+                if (!cpu_is_at91rm9200())
+                        at91_mci_write(host, AT91_MCI_BLKR,
+                                AT91_MCI_BLKR_BCNT(blocks) |
+                                AT91_MCI_BLKR_BLKLEN(block_length));
+
                 /*
                  * Disable the PDC controller
                  */
@@ -584,6 +627,11 @@ static void at91_mci_process_next(struct at91mci_host *host)
                 at91_mci_send_command(host, host->request->stop);
         } else {
                 del_timer(&host->timer);
+                /* the at91rm9200 mci controller hangs after some transfers,
+                 * and the workaround is to reset it after each transfer.
+                 */
+                if (cpu_is_at91rm9200())
+                        at91_reset_host(host);
                 mmc_request_done(host->mmc, host->request);
         }
 }