[PATCH 12/13] [media] omap3isp: Support for deferred probing when requesting DMA channel

Peter Ujfalusi
2015-05-26T13:26:07Z

Switch to use ma_request_slave_channel_compat_reason() to request the DMA
channel. Only fall back to pio mode if the error code returned is not
-EPROBE_DEFER, otherwise return from the probe with the -EPROBE_DEFER.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
CC: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
CC: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
---
drivers/media/platform/omap3isp/isphist.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/media/platform/omap3isp/isphist.c b/drivers/media/platform/omap3isp/isphist.c
index 7138b043a4aa..e690ca13af0e 100644
--- a/drivers/media/platform/omap3isp/isphist.c
+++ b/drivers/media/platform/omap3isp/isphist.c
@@ -499,14 +499,20 @@ int omap3isp_hist_init(struct isp_device *isp)
if (res)
sig = res->start;

- hist->dma_ch = dma_request_slave_channel_compat(mask,
+ hist->dma_ch = dma_request_slave_channel_compat_reason(mask,
omap_dma_filter_fn, &sig, isp->dev, "hist");
- if (!hist->dma_ch)
+ 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;
--
2.3.5