Blackfin SPI Driver: pass DMA overflow error to the higher level

If the SPI bus registers a receive overflow error, pass the result back up
to the higher levels.

Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/spi/spi_bfin5xx.c b/drivers/spi/spi_bfin5xx.c
index 6d3f606..2e0c024 100644 (file)
--- a/drivers/spi/spi_bfin5xx.c
+++ b/drivers/spi/spi_bfin5xx.c
@@ -559,6 +559,7 @@ static irqreturn_t dma_irq_handler(int irq, void *dev_id)
        struct driver_data *drv_data = dev_id;
        struct chip_data *chip = drv_data->cur_chip;
        struct spi_message *msg = drv_data->cur_msg;
+       u16 spistat = read_STAT(drv_data);
 
        dev_dbg(&drv_data->pdev->dev, "in dma_irq_handler\n");
        clear_dma_irqstat(drv_data->dma_channel);
@@ -582,13 +583,18 @@ static irqreturn_t dma_irq_handler(int irq, void *dev_id)
        while (!(read_STAT(drv_data) & SPIF))
                cpu_relax();
 
-       msg->actual_length += drv_data->len_in_bytes;
+       if (spistat & RBSY) {
+               msg->state = ERROR_STATE;
+               dev_err(&drv_data->pdev->dev, "dma receive: fifo/buffer overflow\n");
+       } else {
+               msg->actual_length += drv_data->len_in_bytes;
 
-       if (drv_data->cs_change)
-               cs_deactive(drv_data, chip);
+               if (drv_data->cs_change)
+                       cs_deactive(drv_data, chip);
 
-       /* Move to next transfer */
-       msg->state = next_transfer(drv_data);
+               /* Move to next transfer */
+               msg->state = next_transfer(drv_data);
+       }
 
        /* Schedule transfer tasklet */
        tasklet_schedule(&drv_data->pump_transfers);