dw_dmac: make usage of dw_dma_slave optional

The driver requires a custom slave configuration to be present to be able to
make the slave transfers. Nevertheless, in some cases we need only the request
line as an additional information to the generic slave configuration.  The
request line is provided by slave_id parameter of the dma_slave_config
structure. That's why the custom slave configuration could be optional for such
cases.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c
index a2c5a60bc2e204d0047363cbbc491ab198b2e559..e5378b5741be6a811133ad3a91a81f86a3cce8df 100644 (file)
--- a/drivers/dma/dw_dmac.c
+++ b/drivers/dma/dw_dmac.c
@@ -50,11 +50,12 @@ static inline unsigned int dwc_get_sms(struct dw_dma_slave *slave)
                struct dw_dma_slave *__slave = (_chan->private);        \
                struct dw_dma_chan *_dwc = to_dw_dma_chan(_chan);       \
                struct dma_slave_config *_sconfig = &_dwc->dma_sconfig; \
+               bool _is_slave = is_slave_direction(_dwc->direction);   \
                int _dms = dwc_get_dms(__slave);                \
                int _sms = dwc_get_sms(__slave);                \
-               u8 _smsize = __slave ? _sconfig->src_maxburst : \
+               u8 _smsize = _is_slave ? _sconfig->src_maxburst :       \
                        DW_DMA_MSIZE_16;                        \
-               u8 _dmsize = __slave ? _sconfig->dst_maxburst : \
+               u8 _dmsize = _is_slave ? _sconfig->dst_maxburst :       \
                        DW_DMA_MSIZE_16;                        \
                                                                \
                (DWC_CTLL_DST_MSIZE(_dmsize)                    \
@@ -328,7 +329,7 @@ dwc_descriptor_complete(struct dw_dma_chan *dwc, struct dw_desc *desc,
        list_splice_init(&desc->tx_list, &dwc->free_list);
        list_move(&desc->desc_node, &dwc->free_list);
 
-       if (!dwc->chan.private) {
+       if (!is_slave_direction(dwc->direction)) {
                struct device *parent = chan2parent(&dwc->chan);
                if (!(txd->flags & DMA_COMPL_SKIP_DEST_UNMAP)) {
                        if (txd->flags & DMA_COMPL_DEST_UNMAP_SINGLE)
@@ -804,7 +805,7 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
 
        dev_vdbg(chan2dev(chan), "%s\n", __func__);
 
-       if (unlikely(!dws || !sg_len))
+       if (unlikely(!is_slave_direction(direction) || !sg_len))
                return NULL;
 
        dwc->direction = direction;
@@ -980,8 +981,8 @@ set_runtime_config(struct dma_chan *chan, struct dma_slave_config *sconfig)
 {
        struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
 
-       /* Check if it is chan is configured for slave transfers */
-       if (!chan->private)
+       /* Check if chan will be configured for slave transfers */
+       if (!is_slave_direction(sconfig->direction))
                return -EINVAL;
 
        memcpy(&dwc->dma_sconfig, sconfig, sizeof(*sconfig));