On 06/02/2015 11:09 PM, Jyri Sarha wrote:
Find the configured DMA controller by asking for a DMA channel in the probe phase and releasing it right after. The controller device can be found via the dma_chan struct and the controller is recognized from the compatible property of its device node. The patch assumes EDMA if there is no device node.
Thanks Jyri,
Acked-by: Peter Ujfalusi peter.ujfalusi@ti.com
Signed-off-by: Jyri Sarha jsarha@ti.com
Changes since v2:
- Print only one error message if DMA "probing" fails and none in case of -EPROBE_DEFER
Changes since first patch version:
- Change enum names from MCASP_?DMA to PCM_?DMA
- Return PCM_EDMA if !mcasp->dev->of_node
- Do not ignore possible error code returned by davinci_mcasp_get_dma_type()
sound/soc/davinci/davinci-mcasp.c | 70 +++++++++++++++++++++++++++++++++------ 1 file changed, 60 insertions(+), 10 deletions(-)
diff --git a/sound/soc/davinci/davinci-mcasp.c b/sound/soc/davinci/davinci-mcasp.c index d793494..a73cd57 100644 --- a/sound/soc/davinci/davinci-mcasp.c +++ b/sound/soc/davinci/davinci-mcasp.c @@ -1565,6 +1565,49 @@ static int davinci_mcasp_init_ch_constraints(struct davinci_mcasp *mcasp) return ret; }
+enum {
- PCM_EDMA,
- PCM_SDMA,
+}; +static const char *sdma_prefix = "ti,omap";
+static int davinci_mcasp_get_dma_type(struct davinci_mcasp *mcasp) +{
- struct dma_chan *chan;
- const char *tmp;
- int ret = PCM_EDMA;
- if (!mcasp->dev->of_node)
return PCM_EDMA;- tmp = mcasp->dma_data[SNDRV_PCM_STREAM_PLAYBACK].filter_data;
- chan = dma_request_slave_channel_reason(mcasp->dev, tmp);
- if (IS_ERR(chan)) {
if (PTR_ERR(chan) != -EPROBE_DEFER)dev_err(mcasp->dev,"Can't verify DMA configuration (%ld)\n",PTR_ERR(chan));return PTR_ERR(chan);- }
- BUG_ON(!chan->device || !chan->device->dev);
- if (chan->device->dev->of_node)
ret = of_property_read_string(chan->device->dev->of_node,"compatible", &tmp);- else
dev_dbg(mcasp->dev, "DMA controller has no of-node\n");- dma_release_channel(chan);
- if (ret)
return ret;- dev_dbg(mcasp->dev, "DMA controller compatible = "%s"\n", tmp);
- if (!strncmp(tmp, sdma_prefix, strlen(sdma_prefix)))
return PCM_SDMA;- return PCM_EDMA;
+}
static int davinci_mcasp_probe(struct platform_device *pdev) { struct snd_dmaengine_dai_dma_data *dma_data; @@ -1763,27 +1806,34 @@ static int davinci_mcasp_probe(struct platform_device *pdev) if (ret != 0) goto err;
- switch (mcasp->version) {
- ret = davinci_mcasp_get_dma_type(mcasp);
- switch (ret) {
- case PCM_EDMA:
#if IS_BUILTIN(CONFIG_SND_EDMA_SOC) || \ (IS_MODULE(CONFIG_SND_DAVINCI_SOC_MCASP) && \ IS_MODULE(CONFIG_SND_EDMA_SOC))
- case MCASP_VERSION_1:
- case MCASP_VERSION_2:
- case MCASP_VERSION_3: ret = edma_pcm_platform_register(&pdev->dev);
break;+#else
dev_err(&pdev->dev, "Missing SND_EDMA_SOC\n");ret = -EINVAL;goto err;#endif
break;- case PCM_SDMA:
#if IS_BUILTIN(CONFIG_SND_OMAP_SOC) || \ (IS_MODULE(CONFIG_SND_DAVINCI_SOC_MCASP) && \ IS_MODULE(CONFIG_SND_OMAP_SOC))
- case MCASP_VERSION_4: ret = omap_pcm_platform_register(&pdev->dev);
break;+#else
dev_err(&pdev->dev, "Missing SND_SDMA_SOC\n");ret = -EINVAL;goto err;#endif
break;
dev_err(&pdev->dev, "Invalid McASP version: %d\n",mcasp->version);ret = -EINVAL;
dev_err(&pdev->dev, "No DMA controller found (%d)\n", ret);- case -EPROBE_DEFER:
goto err;