Revert "dmaengine: ep93xx: Don't drain the transfers in terminate_all()"

This reverts commit 81402e4033a7d10c6f841bff364ae0bf0f2fa505.

Signed-off-by: Sasha Levin <alexander.levin@verizon.com>

diff --git a/drivers/dma/ep93xx_dma.c b/drivers/dma/ep93xx_dma.c
index 1638d39af5955eca58d44ec60f347faf7b60d9f4..023c08708b56af0941b9a5c9b70fa15c83eb972f 100644 (file)
--- a/drivers/dma/ep93xx_dma.c
+++ b/drivers/dma/ep93xx_dma.c
@@ -201,7 +201,6 @@ struct ep93xx_dma_engine {
        struct dma_device       dma_dev;
        bool                    m2m;
        int                     (*hw_setup)(struct ep93xx_dma_chan *);
-       void                    (*hw_synchronize)(struct ep93xx_dma_chan *);
        void                    (*hw_shutdown)(struct ep93xx_dma_chan *);
        void                    (*hw_submit)(struct ep93xx_dma_chan *);
        int                     (*hw_interrupt)(struct ep93xx_dma_chan *);
@@ -336,27 +335,21 @@ static inline u32 m2p_channel_state(struct ep93xx_dma_chan *edmac)
        return (readl(edmac->regs + M2P_STATUS) >> 4) & 0x3;
 }
 
-static void m2p_hw_synchronize(struct ep93xx_dma_chan *edmac)
+static void m2p_hw_shutdown(struct ep93xx_dma_chan *edmac)
 {
-       unsigned long flags;
        u32 control;
 
-       spin_lock_irqsave(&edmac->lock, flags);
        control = readl(edmac->regs + M2P_CONTROL);
        control &= ~(M2P_CONTROL_STALLINT | M2P_CONTROL_NFBINT);
        m2p_set_control(edmac, control);
-       spin_unlock_irqrestore(&edmac->lock, flags);
 
        while (m2p_channel_state(edmac) >= M2P_STATE_ON)
-               schedule();
-}
+               cpu_relax();
 
-static void m2p_hw_shutdown(struct ep93xx_dma_chan *edmac)
-{
        m2p_set_control(edmac, 0);
 
-       while (m2p_channel_state(edmac) != M2P_STATE_IDLE)
-               dev_warn(chan2dev(edmac), "M2P: Not yet IDLE\n");
+       while (m2p_channel_state(edmac) == M2P_STATE_STALL)
+               cpu_relax();
 }
 
 static void m2p_fill_desc(struct ep93xx_dma_chan *edmac)
@@ -1171,26 +1164,6 @@ fail:
        return NULL;
 }
 
-/**
- * ep93xx_dma_synchronize - Synchronizes the termination of transfers to the
- * current context.
- * @chan: channel
- *
- * Synchronizes the DMA channel termination to the current context. When this
- * function returns it is guaranteed that all transfers for previously issued
- * descriptors have stopped and and it is safe to free the memory associated
- * with them. Furthermore it is guaranteed that all complete callback functions
- * for a previously submitted descriptor have finished running and it is safe to
- * free resources accessed from within the complete callbacks.
- */
-static void ep93xx_dma_synchronize(struct dma_chan *chan)
-{
-       struct ep93xx_dma_chan *edmac = to_ep93xx_dma_chan(chan);
-
-       if (edmac->edma->hw_synchronize)
-               edmac->edma->hw_synchronize(edmac);
-}
-
 /**
  * ep93xx_dma_terminate_all - terminate all transactions
  * @chan: channel
@@ -1354,7 +1327,6 @@ static int __init ep93xx_dma_probe(struct platform_device *pdev)
        dma_dev->device_prep_slave_sg = ep93xx_dma_prep_slave_sg;
        dma_dev->device_prep_dma_cyclic = ep93xx_dma_prep_dma_cyclic;
        dma_dev->device_config = ep93xx_dma_slave_config;
-       dma_dev->device_synchronize = ep93xx_dma_synchronize;
        dma_dev->device_terminate_all = ep93xx_dma_terminate_all;
        dma_dev->device_issue_pending = ep93xx_dma_issue_pending;
        dma_dev->device_tx_status = ep93xx_dma_tx_status;
@@ -1372,7 +1344,6 @@ static int __init ep93xx_dma_probe(struct platform_device *pdev)
        } else {
                dma_cap_set(DMA_PRIVATE, dma_dev->cap_mask);
 
-               edma->hw_synchronize = m2p_hw_synchronize;
                edma->hw_setup = m2p_hw_setup;
                edma->hw_shutdown = m2p_hw_shutdown;
                edma->hw_submit = m2p_hw_submit;