[PATCH RESEND] dmaengine: stm32-dma: Add error messages if xlate fails

[M'boumba Cedric Madianga]

This patch adds some error messages when a slave device fails to request a
channel.

Signed-off-by: M'boumba Cedric Madianga <cedric.madia...@gmail.com>
Reviewed-by: Ludovic BARRE <ludovic.ba...@st.com>
---
Resolve conflicts issue
---
 drivers/dma/stm32-dma.c | 24 +++++++++++++++---------
 1 file changed, 15 insertions(+), 9 deletions(-)

diff --git a/drivers/dma/stm32-dma.c b/drivers/dma/stm32-dma.c
index fc9738e..4eacd9d 100644
--- a/drivers/dma/stm32-dma.c
+++ b/drivers/dma/stm32-dma.c
@@ -987,30 +987,36 @@ static struct dma_chan *stm32_dma_of_xlate(struct 
of_phandle_args *dma_spec,
                                           struct of_dma *ofdma)
 {
        struct stm32_dma_device *dmadev = ofdma->of_dma_data;
+       struct device *dev = dmadev->ddev.dev;
        struct stm32_dma_cfg cfg;
        struct stm32_dma_chan *chan;
        struct dma_chan *c;
 
-       if (dma_spec->args_count < 3)
+       if (dma_spec->args_count < 4) {
+               dev_err(dev, "Bad number of cells\n");
                return NULL;
+       }
 
        cfg.channel_id = dma_spec->args[0];
        cfg.request_line = dma_spec->args[1];
        cfg.stream_config = dma_spec->args[2];
-       cfg.threshold = 0;
+       cfg.threshold = dma_spec->args[3];
 
-       if ((cfg.channel_id >= STM32_DMA_MAX_CHANNELS) || (cfg.request_line >=
-                               STM32_DMA_MAX_REQUEST_ID))
+       if ((cfg.channel_id >= STM32_DMA_MAX_CHANNELS) ||
+           (cfg.request_line >= STM32_DMA_MAX_REQUEST_ID)) {
+               dev_err(dev, "Bad channel and/or request id\n");
                return NULL;
-
-       if (dma_spec->args_count > 3)
-               cfg.threshold = dma_spec->args[3];
+       }
 
        chan = &dmadev->chan[cfg.channel_id];
 
        c = dma_get_slave_channel(&chan->vchan.chan);
-       if (c)
-               stm32_dma_set_config(chan, &cfg);
+       if (!c) {
+               dev_err(dev, "No more channel avalaible\n");
+               return NULL;
+       }
+
+       stm32_dma_set_config(chan, &cfg);
 
        return c;
 }
-- 
1.9.1