From 13b3006b8ebd60926a60fc378ff6fe8affa9a194 Mon Sep 17 00:00:00 2001 From: Daniel Mack Date: Sat, 10 Aug 2013 18:52:18 +0200 Subject: [PATCH] dma: mmp_pdma: add filter function PXA peripherals need to obtain specific DMA request ids which will eventually be stored in the DRCMR register. Currently, clients are expected to store that number inside the slave config block as slave_id, which is unfortunately incompatible with the way DMA resources are handled in DT environments. This patch adds a filter function which stores the filter parameter passed in by of-dma.c into the channel's drcmr register. For backward compatability, cfg->slave_id is still used if set to a non-zero value. Signed-off-by: Daniel Mack Acked-by: Arnd Bergmann Signed-off-by: Vinod Koul --- drivers/dma/mmp_pdma.c | 21 ++++++++++++++++++++- include/linux/dma/mmp-pdma.h | 15 +++++++++++++++ 2 files changed, 35 insertions(+), 1 deletion(-) create mode 100644 include/linux/dma/mmp-pdma.h diff --git a/drivers/dma/mmp_pdma.c b/drivers/dma/mmp_pdma.c index eb75d4b4bafe..dd024d4759e7 100644 --- a/drivers/dma/mmp_pdma.c +++ b/drivers/dma/mmp_pdma.c @@ -19,6 +19,7 @@ #include #include #include +#include #include "dmaengine.h" @@ -635,8 +636,13 @@ static int mmp_pdma_control(struct dma_chan *dchan, enum dma_ctrl_cmd cmd, chan->dcmd |= DCMD_BURST32; chan->dir = cfg->direction; - chan->drcmr = cfg->slave_id; chan->dev_addr = addr; + /* FIXME: drivers should be ported over to use the filter + * function. Once that's done, the following two lines can + * be removed. + */ + if (cfg->slave_id) + chan->drcmr = cfg->slave_id; break; default: return -ENOSYS; @@ -877,6 +883,19 @@ static struct platform_driver mmp_pdma_driver = { .remove = mmp_pdma_remove, }; +bool mmp_pdma_filter_fn(struct dma_chan *chan, void *param) +{ + struct mmp_pdma_chan *c = to_mmp_pdma_chan(chan); + + if (chan->device->dev->driver != &mmp_pdma_driver.driver) + return false; + + c->drcmr = *(unsigned int *) param; + + return true; +} +EXPORT_SYMBOL_GPL(mmp_pdma_filter_fn); + module_platform_driver(mmp_pdma_driver); MODULE_DESCRIPTION("MARVELL MMP Periphera DMA Driver"); diff --git a/include/linux/dma/mmp-pdma.h b/include/linux/dma/mmp-pdma.h new file mode 100644 index 000000000000..2dc9b2bc18fc --- /dev/null +++ b/include/linux/dma/mmp-pdma.h @@ -0,0 +1,15 @@ +#ifndef _MMP_PDMA_H_ +#define _MMP_PDMA_H_ + +struct dma_chan; + +#ifdef CONFIG_MMP_PDMA +bool mmp_pdma_filter_fn(struct dma_chan *chan, void *param); +#else +static inline bool mmp_pdma_filter_fn(struct dma_chan *chan, void *param) +{ + return false; +} +#endif + +#endif /* _MMP_PDMA_H_ */