Blackfin SPI Driver: add a few more DMA debug messages

Because of DMA hardware issue, we were trying to use software workaround.
This patch add some useful debug messages to help us debugging the DMA
code.

Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
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 0bbe19e..5acec9f 100644 (file)
--- a/drivers/spi/spi_bfin5xx.c
+++ b/drivers/spi/spi_bfin5xx.c
@@ -559,9 +559,13 @@ 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;
+       unsigned short dmastat = get_dma_curr_irqstat(drv_data->dma_channel);
        u16 spistat = read_STAT(drv_data);
 
-       dev_dbg(&drv_data->pdev->dev, "in dma_irq_handler\n");
+       dev_dbg(&drv_data->pdev->dev,
+               "in dma_irq_handler dmastat:0x%x spistat:0x%x\n",
+               dmastat, spistat);
+
        clear_dma_irqstat(drv_data->dma_channel);
 
        /* Wait for DMA to complete */
@@ -631,6 +635,7 @@ static void pump_transfers(unsigned long data)
 
         /* Handle for abort */
        if (message->state == ERROR_STATE) {
+               dev_dbg(&drv_data->pdev->dev, "transfer: we've hit an error\n");
                message->status = -EIO;
                giveback(drv_data);
                return;
@@ -638,6 +643,7 @@ static void pump_transfers(unsigned long data)
 
        /* Handle end of message */
        if (message->state == DONE_STATE) {
+               dev_dbg(&drv_data->pdev->dev, "transfer: all done!\n");
                message->status = 0;
                giveback(drv_data);
                return;
@@ -645,6 +651,7 @@ static void pump_transfers(unsigned long data)
 
        /* Delay if requested at end of transfer */
        if (message->state == RUNNING_STATE) {
+               dev_dbg(&drv_data->pdev->dev, "transfer: still running ...\n");
                previous = list_entry(transfer->transfer_list.prev,
                                      struct spi_transfer, transfer_list);
                if (previous->delay_usecs)
@@ -806,7 +813,8 @@ static void pump_transfers(unsigned long data)
                dma_config = (RESTART | dma_width | DI_EN);
                if (drv_data->rx != NULL) {
                        /* set transfer mode, and enable SPI */
-                       dev_dbg(&drv_data->pdev->dev, "doing DMA in.\n");
+                       dev_dbg(&drv_data->pdev->dev, "doing DMA in to %p (size %zx)\n",
+                               drv_data->rx, drv_data->len_in_bytes);
 
                        /* invalidate caches, if needed */
                        if (bfin_addr_dcachable((unsigned long) drv_data->rx))