ENGR00231773-2 ASRC: add work struct for asrc output data receive

SDMA driver can't promise receive all output data generated. Cause when
the data in output FIFO is less than ASRC output FIFO watermark, there
would be no DMA request generated and thus no SDMA transfer would
happens.

In this patch, add work struct to support ASRC driver receive last part
of data in OUTPUT FIFO in polling way.

Signed-off-by: Chen Liangjun <b36089@freescale.com>

diff --git a/drivers/mxc/asrc/mxc_asrc.c b/drivers/mxc/asrc/mxc_asrc.c
index 13cf635b4f03496b057de0919a11adb6e3339767..8ce2197be9b231089917be9567b5cda0e81d744e 100644 (file)
--- a/drivers/mxc/asrc/mxc_asrc.c
+++ b/drivers/mxc/asrc/mxc_asrc.c
@@ -860,9 +860,20 @@ static void asrc_output_dma_callback(void *data)
        params->output_counter++;
        wake_up_interruptible(&params->output_wait_queue);
        spin_unlock_irqrestore(&output_int_lock, lock_flags);
+
+       schedule_work(&params->task_output_work);
        return;
 }
 
+static void asrc_output_task_worker(struct work_struct *w)
+{
+       struct asrc_pair_params *params =
+               container_of(w, struct asrc_pair_params, task_output_work);
+
+       /* asrc output work struct */
+}
+
+
 static void mxc_free_dma_buf(struct asrc_pair_params *params)
 {
        if (params->input_dma_total.dma_vaddr != NULL) {
@@ -1140,6 +1151,10 @@ static long asrc_ioctl(struct file *file,
 
                        init_waitqueue_head(&params->input_wait_queue);
                        init_waitqueue_head(&params->output_wait_queue);
+                       /* Add work struct to cover the task of
+                        * receive last period of output data.*/
+                       INIT_WORK(&params->task_output_work,
+                                               asrc_output_task_worker);
 
                        if (copy_to_user
                            ((void __user *)arg, &config,

diff --git a/include/linux/mxc_asrc.h b/include/linux/mxc_asrc.h
index 638d401256d79cc844f0ff65d83ad90b0d213842..4d6149a64be948784d883f6d78b50b3d76709f38 100644 (file)
--- a/include/linux/mxc_asrc.h
+++ b/include/linux/mxc_asrc.h
@@ -215,6 +215,7 @@ struct asrc_pair_params {
        struct dma_block output_dma[ASRC_DMA_BUFFER_NUM];
        struct dma_async_tx_descriptor *desc_in;
        struct dma_async_tx_descriptor *desc_out;
+       struct work_struct task_output_work;
 };
 
 struct asrc_data {