On Thu, Oct 23, 2014 at 04:38:39PM +0300, Laurent Pinchart wrote:

Hi Maxime,

On Thursday 23 October 2014 15:19:33 Maxime Ripard wrote:

quoted

On Thu, Oct 23, 2014 at 12:21:31AM +0300, Laurent Pinchart wrote:

quoted

Hi Maxime,

Thank you for the patch.

On Wednesday 22 October 2014 17:44:12 Maxime Ripard wrote:

quoted

For the slave caps retrieval to be really useful, most drivers need to
implement it.

Hence, we need to be slightly more aggressive, and trigger a warning at
registration time for drivers that don't fill their caps infos in order
to
encourage them to implement it.

Signed-off-by: Maxime Ripard <redacted>
---

 drivers/dma/dmaengine.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 98e9431f85ec..4e18981b16bd 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c

@@ -827,6 +827,9 @@ int dma_async_device_register(struct dma_device

*device) BUG_ON(!device->device_issue_pending);

 	BUG_ON(!device->dev);

+	WARN(dma_has_cap(DMA_SLAVE, device->cap_mask) &&
!device->generic_slave_caps,
+	     "this driver doesn't support generic slave capabilities
reporting\n");
+

This might be slightly too aggressive.

I disagree with that. If we want at some point to have the drivers
implement it, we should be aggressive (and note that we don't break
anything, the driver will still work as it used to).

I meant too aggressive given the possibility that a driver might need its own 
implementation if not all channels have the same capability.

Then we'll remove this warning, or rework it, when we will need it,
and hopefully by then, a lot of drivers will have fixed theirs :)

Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
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