[PATCH v3 07/21] ARM: dts: parse DMA config in pxamci

Sergei Ianovich
2013-12-17T19:37:37Z

The existing PXA MMC driver cannot get DMA channels in a proper
way from the respective device tree binding.

This patch provides temporary workaround which allows using the
existing driver in DT machines by pointing to the proper
dmaengine-based "marvell,pdma-1.0" DMA.

Even though the new DMA provider is not present we can parse device node
attributes manually and use channel numbers to acquire DMA channel
from the existing non-dmaengine provider.

When Daniel's DMA series is merged there will be no need to manually
parse for "dmas" and this patch can be safely reverted.

Signed-off-by: Sergei Ianovich <ynvich@gmail.com>
CC: Daniel Mack <zonque@gmail.com>
CC: Arnd Bergmann <arnd@arndb.de>
---
v2..v3
* split into good (PATCH 07/21) and temporary (this one) parts

v1..v2
* add binding for next-gen dma controller
* use correct dma declararion
* number changed from 5 to 3

drivers/mmc/host/pxamci.c | 59 ++++++++++++++++++++++++++++++++++++++---------
1 file changed, 48 insertions(+), 11 deletions(-)

diff --git a/drivers/mmc/host/pxamci.c b/drivers/mmc/host/pxamci.c
index 32fe113..6b67764 100644
--- a/drivers/mmc/host/pxamci.c
+++ b/drivers/mmc/host/pxamci.c
@@ -613,11 +613,46 @@ static int pxamci_of_init(struct platform_device *pdev)

return 0;
}
+
+static int pxamci_of_init_dma(struct platform_device *pdev,
+ struct pxamci_host *host)
+{
+ struct device_node *np = pdev->dev.of_node;
+ u32 tmp;
+ int i;
+ int ret;
+
+ i = of_property_match_string(np, "dma-names", "rx");
+ if (i < 0)
+ return i;
+
+ ret = of_property_read_u32_index(np, "dmas", 2 * i + 1, &tmp);
+ if (ret < 0)
+ return ret;
+ host->dma_drcmrrx = tmp;
+
+ i = of_property_match_string(np, "dma-names", "tx");
+ if (i < 0)
+ return i;
+
+ ret = of_property_read_u32_index(np, "dmas", 2 * i + 1, &tmp);
+ if (ret < 0)
+ return ret;
+ host->dma_drcmrtx = tmp;
+
+ return 0;
+}
#else
static int pxamci_of_init(struct platform_device *pdev)
{
return 0;
}
+
+static int pxamci_of_init_dma(struct platform_device *pdev,
+ struct pxamci_host *host)
+{
+ return -ENODATA;
+}
#endif

static int pxamci_probe(struct platform_device *pdev)
@@ -741,19 +776,21 @@ static int pxamci_probe(struct platform_device *pdev)

platform_set_drvdata(pdev, mmc);

- dmarx = platform_get_resource(pdev, IORESOURCE_DMA, 0);
- if (!dmarx) {
- ret = -ENXIO;
- goto out;
- }
- host->dma_drcmrrx = dmarx->start;
+ if (pxamci_of_init_dma(pdev, host) < 0) {
+ dmarx = platform_get_resource(pdev, IORESOURCE_DMA, 0);
+ if (!dmarx) {
+ ret = -ENXIO;
+ goto out;
+ }
+ host->dma_drcmrrx = dmarx->start;

- dmatx = platform_get_resource(pdev, IORESOURCE_DMA, 1);
- if (!dmatx) {
- ret = -ENXIO;
- goto out;
+ dmatx = platform_get_resource(pdev, IORESOURCE_DMA, 1);
+ if (!dmatx) {
+ ret = -ENXIO;
+ goto out;
+ }
+ host->dma_drcmrtx = dmatx->start;
}
- host->dma_drcmrtx = dmatx->start;

if (host->pdata) {
gpio_cd = host->pdata->gpio_card_detect;
--
1.8.4.2