DMAENGINE: ste_dma40: avoid doing unnessecary suspend

Avoid doing unnessecary suspend when modifying logical channels.

Signed-off-by: Jonas Aaberg <jonas.aberg@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 7 insertions, 32 deletions

diff --git a/drivers/dma/ste_dma40.c b/drivers/dma/ste_dma40.c
index ebffb53c036c..abbc1b627bcc 100644
--- a/drivers/dma/ste_dma40.c
+++ b/drivers/dma/ste_dma40.c
@@ -595,6 +595,7 @@ static void d40_config_set_event(struct d40_chan *d40c, bool do_enable)
         u32 val;
         unsigned long flags;
 
+        /* Notice, that disable requires the physical channel to be stopped */
         if (do_enable)
                 val = D40_ACTIVATE_EVENTLINE;
         else
@@ -740,18 +741,10 @@ static dma_cookie_t d40_tx_submit(struct dma_async_tx_descriptor *tx)
 
 static int d40_start(struct d40_chan *d40c)
 {
-        int err;
-
-        if (d40c->log_num != D40_PHY_CHAN) {
-                err = d40_channel_execute_command(d40c, D40_DMA_SUSPEND_REQ);
-                if (err)
-                        return err;
+        if (d40c->log_num != D40_PHY_CHAN)
                 d40_config_set_event(d40c, true);
-        }
-
-        err = d40_channel_execute_command(d40c, D40_DMA_RUN);
 
-        return err;
+        return d40_channel_execute_command(d40c, D40_DMA_RUN);
 }
 
 static struct d40_desc *d40_queue_start(struct d40_chan *d40c)
@@ -1340,7 +1333,6 @@ static bool d40_is_paused(struct d40_chan *d40c)
         void __iomem *active_reg;
         u32 status;
         u32 event;
-        int res;
 
         spin_lock_irqsave(&d40c->lock, flags);
 
@@ -1359,10 +1351,6 @@ static bool d40_is_paused(struct d40_chan *d40c)
                 goto _exit;
         }
 
-        res = d40_channel_execute_command(d40c, D40_DMA_SUSPEND_REQ);
-        if (res != 0)
-                goto _exit;
-
         if (d40c->dma_cfg.dir == STEDMA40_MEM_TO_PERIPH ||
             d40c->dma_cfg.dir == STEDMA40_MEM_TO_MEM)
                 event = D40_TYPE_TO_EVENT(d40c->dma_cfg.dst_dev_type);
@@ -1379,12 +1367,6 @@ static bool d40_is_paused(struct d40_chan *d40c)
 
         if (status != D40_DMA_RUN)
                 is_paused = true;
-
-        /* Resume the other logical channels if any */
-        if (d40_chan_has_events(d40c))
-                res = d40_channel_execute_command(d40c,
-                                                  D40_DMA_RUN);
-
 _exit:
         spin_unlock_irqrestore(&d40c->lock, flags);
         return is_paused;
@@ -1430,20 +1412,13 @@ static int d40_resume(struct dma_chan *chan)
 
         spin_lock_irqsave(&d40c->lock, flags);
 
-        if (d40c->log_num != D40_PHY_CHAN) {
-                res = d40_channel_execute_command(d40c, D40_DMA_SUSPEND_REQ);
-                if (res)
-                        goto out;
-
-                /* If bytes left to transfer or linked tx resume job */
-                if (d40_residue(d40c) || d40_tx_is_linked(d40c)) {
+        /* If bytes left to transfer or linked tx resume job */
+        if (d40_residue(d40c) || d40_tx_is_linked(d40c)) {
+                if (d40c->log_num != D40_PHY_CHAN)
                         d40_config_set_event(d40c, true);
-                        res = d40_channel_execute_command(d40c, D40_DMA_RUN);
-                }
-        } else if (d40_residue(d40c) || d40_tx_is_linked(d40c))
                 res = d40_channel_execute_command(d40c, D40_DMA_RUN);
+        }
 
-out:
         spin_unlock_irqrestore(&d40c->lock, flags);
         return res;
 }