@@ -599,6 +599,9 @@ int dma_get_slave_caps(struct dma_chan *chan, struct dma_slave_caps *caps)
caps->cmd_resume = !!device->device_resume;
caps->cmd_terminate = !!device->device_terminate_all;
+ if (device->device_caps)
+ device->device_caps(chan, caps);
+
return 0;
}
EXPORT_SYMBOL_GPL(dma_get_slave_caps);
@@ -899,6 +899,8 @@ struct dma_device {
struct dma_chan *chan, dma_addr_t dst, u64 data,
unsigned long flags);
+ void (*device_caps)(struct dma_chan *chan,
+ struct dma_slave_caps *caps);
int (*device_config)(struct dma_chan *chan,
struct dma_slave_config *config);
int (*device_pause)(struct dma_chan *chan);
There are DMA devices (like ours version of Synopsys DW DMAC) which have DMA capabilities non-uniformly redistributed amongst the device channels. In order to provide a way of exposing the channel-specific parameters to the DMA engine consumers, we introduce a new DMA-device callback. In case if provided it gets called from the dma_get_slave_caps() method and is able to override the generic DMA-device capabilities. Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru> Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Rob Herring <robh+dt@kernel.org> Cc: linux-mips@vger.kernel.org Cc: devicetree@vger.kernel.org --- Changelog v3: - This is a new patch created as a result of the discussion with Vinod and Andy in the framework of DW DMA burst and LLP capabilities. --- drivers/dma/dmaengine.c | 3 +++ include/linux/dmaengine.h | 2 ++ 2 files changed, 5 insertions(+)