[PATCH v6 7/9] dmaengine: dw: Add dummy device_caps callback

From: Serge Semin
Date: Wed Jun 17 2020 - 19:41:32 EST


Since some DW DMA controllers (like one installed on Baikal-T1 SoC) may
have non-uniform DMA capabilities per device channels, let's add
the DW DMA specific device_caps callback to expose that specifics up to
the DMA consumer. It's a dummy function for now. We'll fill it in with
capabilities overrides in the next commits.

Signed-off-by: Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx>
Cc: Alexey Malahov <Alexey.Malahov@xxxxxxxxxxxxxxxxxxxx>
Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Rob Herring <robh+dt@xxxxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxxx
Cc: devicetree@xxxxxxxxxxxxxxx

---

Changelog v3:
- This is a new patch created as a result of the discussion with Vinud and
Andy in the framework of DW DMA burst and LLP capabilities.
---
drivers/dma/dw/core.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c
index fb95920c429e..ceded21537e2 100644
--- a/drivers/dma/dw/core.c
+++ b/drivers/dma/dw/core.c
@@ -1049,6 +1049,11 @@ static void dwc_free_chan_resources(struct dma_chan *chan)
dev_vdbg(chan2dev(chan), "%s: done\n", __func__);
}

+static void dwc_caps(struct dma_chan *chan, struct dma_slave_caps *caps)
+{
+
+}
+
int do_dma_probe(struct dw_dma_chip *chip)
{
struct dw_dma *dw = chip->dw;
@@ -1214,6 +1219,7 @@ int do_dma_probe(struct dw_dma_chip *chip)
dw->dma.device_prep_dma_memcpy = dwc_prep_dma_memcpy;
dw->dma.device_prep_slave_sg = dwc_prep_slave_sg;

+ dw->dma.device_caps = dwc_caps;
dw->dma.device_config = dwc_config;
dw->dma.device_pause = dwc_pause;
dw->dma.device_resume = dwc_resume;
--
2.26.2