dmaengine: dw: move residue to a descriptor

Residue is a property of any active descriptor. So, any descriptor may be in
different state but residue is a feature of active descriptor. Check if the
asked descriptor is active and return proper residue value for it.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c
index 848d335..a6d96f3 100644 (file)
--- a/drivers/dma/dw/core.c
+++ b/drivers/dma/dw/core.c
@@ -242,7 +242,7 @@ static void dwc_dostart(struct dw_dma_chan *dwc, struct dw_desc *first)
 
                dwc_initialize(dwc);
 
-               dwc->residue = first->total_len;
+               first->residue = first->total_len;
                dwc->tx_node_active = &first->tx_list;
 
                /* Submit first block */
@@ -372,11 +372,11 @@ static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc)
 
                        head = &desc->tx_list;
                        if (active != head) {
-                               /* Update desc to reflect last sent one */
-                               if (active != head->next)
-                                       desc = to_dw_desc(active->prev);
-
-                               dwc->residue -= desc->len;
+                               /* Update residue to reflect last sent descriptor */
+                               if (active == head->next)
+                                       desc->residue -= desc->len;
+                               else
+                                       desc->residue -= to_dw_desc(active->prev)->len;
 
                                child = to_dw_desc(active);
 
@@ -391,8 +391,6 @@ static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc)
                        clear_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags);
                }
 
-               dwc->residue = 0;
-
                spin_unlock_irqrestore(&dwc->lock, flags);
 
                dwc_complete_all(dw, dwc);
@@ -400,7 +398,6 @@ static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc)
        }
 
        if (list_empty(&dwc->active_list)) {
-               dwc->residue = 0;
                spin_unlock_irqrestore(&dwc->lock, flags);
                return;
        }
@@ -415,7 +412,7 @@ static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc)
 
        list_for_each_entry_safe(desc, _desc, &dwc->active_list, desc_node) {
                /* Initial residue value */
-               dwc->residue = desc->total_len;
+               desc->residue = desc->total_len;
 
                /* Check first descriptors addr */
                if (desc->txd.phys == DWC_LLP_LOC(llp)) {
@@ -426,20 +423,20 @@ static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc)
                /* Check first descriptors llp */
                if (lli_read(desc, llp) == llp) {
                        /* This one is currently in progress */
-                       dwc->residue -= dwc_get_sent(dwc);
+                       desc->residue -= dwc_get_sent(dwc);
                        spin_unlock_irqrestore(&dwc->lock, flags);
                        return;
                }
 
-               dwc->residue -= desc->len;
+               desc->residue -= desc->len;
                list_for_each_entry(child, &desc->tx_list, desc_node) {
                        if (lli_read(child, llp) == llp) {
                                /* Currently in progress */
-                               dwc->residue -= dwc_get_sent(dwc);
+                               desc->residue -= dwc_get_sent(dwc);
                                spin_unlock_irqrestore(&dwc->lock, flags);
                                return;
                        }
-                       dwc->residue -= child->len;
+                       desc->residue -= child->len;
                }
 
                /*
@@ -1059,16 +1056,37 @@ static int dwc_terminate_all(struct dma_chan *chan)
        return 0;
 }
 
-static inline u32 dwc_get_residue(struct dw_dma_chan *dwc)
+static struct dw_desc *dwc_find_desc(struct dw_dma_chan *dwc, dma_cookie_t c)
+{
+       struct dw_desc *desc;
+
+       list_for_each_entry(desc, &dwc->active_list, desc_node)
+               if (desc->txd.cookie == c)
+                       return desc;
+
+       return NULL;
+}
+
+static u32 dwc_get_residue(struct dw_dma_chan *dwc, dma_cookie_t cookie)
 {
+       struct dw_desc *desc;
        unsigned long flags;
        u32 residue;
 
        spin_lock_irqsave(&dwc->lock, flags);
 
-       residue = dwc->residue;
-       if (test_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags) && residue)
-               residue -= dwc_get_sent(dwc);
+       desc = dwc_find_desc(dwc, cookie);
+       if (desc) {
+               if (desc == dwc_first_active(dwc)) {
+                       residue = desc->residue;
+                       if (test_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags) && residue)
+                               residue -= dwc_get_sent(dwc);
+               } else {
+                       residue = desc->total_len;
+               }
+       } else {
+               residue = 0;
+       }
 
        spin_unlock_irqrestore(&dwc->lock, flags);
        return residue;
@@ -1089,8 +1107,10 @@ dwc_tx_status(struct dma_chan *chan,
        dwc_scan_descriptors(to_dw_dma(chan->device), dwc);
 
        ret = dma_cookie_status(chan, cookie, txstate);
-       if (ret != DMA_COMPLETE)
-               dma_set_residue(txstate, dwc_get_residue(dwc));
+       if (ret == DMA_COMPLETE)
+               return ret;
+
+       dma_set_residue(txstate, dwc_get_residue(dwc, cookie));
 
        if (test_bit(DW_DMA_IS_PAUSED, &dwc->flags) && ret == DMA_IN_PROGRESS)
                return DMA_PAUSED;

diff --git a/drivers/dma/dw/regs.h b/drivers/dma/dw/regs.h
index 8917864..96f4981 100644 (file)
--- a/drivers/dma/dw/regs.h
+++ b/drivers/dma/dw/regs.h
@@ -237,7 +237,6 @@ struct dw_dma_chan {
        struct list_head        active_list;
        struct list_head        queue;
        struct list_head        free_list;
-       u32                     residue;
        struct dw_cyclic_desc   *cdesc;
 
        unsigned int            descs_allocated;
@@ -352,6 +351,7 @@ struct dw_desc {
        struct dma_async_tx_descriptor  txd;
        size_t                          len;
        size_t                          total_len;
+       u32                             residue;
 };
 
 #define to_dw_desc(h)  list_entry(h, struct dw_desc, desc_node)