[PATCH] media: omap3isp: Use dma_request_chan() to requesting DMA channel

From: Peter Ujfalusi
Date: Fri Apr 29 2016 - 09:05:42 EST


With the new dma_request_chan() the client driver does not need to look for
the DMA resource and it does not need to pass filter_fn anymore.
By switching to the new API the driver can now support deferred probing
against DMA.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
CC: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
CC: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxx>
---
drivers/media/platform/omap3isp/isphist.c | 27 +++++++++------------------
1 file changed, 9 insertions(+), 18 deletions(-)

diff --git a/drivers/media/platform/omap3isp/isphist.c b/drivers/media/platform/omap3isp/isphist.c
index 7138b043a4aa..e163e3d92517 100644
--- a/drivers/media/platform/omap3isp/isphist.c
+++ b/drivers/media/platform/omap3isp/isphist.c
@@ -18,7 +18,6 @@
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/dmaengine.h>
-#include <linux/omap-dmaengine.h>
#include <linux/slab.h>
#include <linux/uaccess.h>

@@ -486,27 +485,19 @@ int omap3isp_hist_init(struct isp_device *isp)
hist->isp = isp;

if (HIST_CONFIG_DMA) {
- struct platform_device *pdev = to_platform_device(isp->dev);
- struct resource *res;
- unsigned int sig = 0;
- dma_cap_mask_t mask;
-
- dma_cap_zero(mask);
- dma_cap_set(DMA_SLAVE, mask);
-
- res = platform_get_resource_byname(pdev, IORESOURCE_DMA,
- "hist");
- if (res)
- sig = res->start;
-
- hist->dma_ch = dma_request_slave_channel_compat(mask,
- omap_dma_filter_fn, &sig, isp->dev, "hist");
- if (!hist->dma_ch)
+ hist->dma_ch = dma_request_chan(isp->dev, "hist");
+ if (IS_ERR(hist->dma_ch)) {
+ ret = PTR_ERR(hist->dma_ch);
+ if (ret == -EPROBE_DEFER)
+ return ret;
+
+ hist->dma_ch = NULL;
dev_warn(isp->dev,
"hist: DMA channel request failed, using PIO\n");
- else
+ } else {
dev_dbg(isp->dev, "hist: using DMA channel %s\n",
dma_chan_name(hist->dma_ch));
+ }
}

hist->ops = &hist_ops;
--
2.8.1