Messages in this thread | | | Date | Tue, 30 Aug 2011 09:54:04 +0200 (CEST) | From | Guennadi Liakhovetski <> | Subject | Re: [PATCH] serial: sh-sci: don't filter on DMA device, use only channel ID |
| |
On Mon, 29 Aug 2011, Vinod Koul wrote:
> On Mon, 2011-08-29 at 17:16 +0900, Magnus Damm wrote: > > On Mon, Aug 29, 2011 at 5:00 PM, Paul Mundt <lethal@linux-sh.org> wrote: > > > On Fri, Jun 24, 2011 at 05:17:51PM +0530, Koul, Vinod wrote: > > >> On Fri, 2011-06-24 at 13:56 +0200, Guennadi Liakhovetski wrote: > > >> > On some sh-mobile systems there are more than one DMA controllers, that > > >> > can be used for serial ports. Specifying a DMA device in sh-sci platform > > >> > data unnecessarily restricts the driver to only use one DMA controller. > > >> > > > >> > Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> > > >> > --- > > >> > drivers/tty/serial/sh-sci.c | 25 ++++++++----------------- > > >> > include/linux/serial_sci.h | 2 -- > > >> > 2 files changed, 8 insertions(+), 19 deletions(-) > > >> > > > >> > diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c > > >> > index ebd8629..8711f4e 100644 > > >> > --- a/drivers/tty/serial/sh-sci.c > > >> > +++ b/drivers/tty/serial/sh-sci.c > > >> > @@ -1295,12 +1295,8 @@ static bool filter(struct dma_chan *chan, void *slave) > > >> > dev_dbg(chan->device->dev, "%s: slave ID %d\n", __func__, > > >> > param->slave_id); > > >> > > > >> > - if (param->dma_dev == chan->device->dev) { > > >> > - chan->private = param; > > >> > - return true; > > >> > - } else { > > >> > - return false; > > >> > - } > > >> > + chan->private = param; > > >> > + return true; > > >> You should not assign chan->private. > > >> Please move this to dma_slave_control API > > > > > > I haven't seen any reply to this comment and this patch seems to still be > > > outstanding, is there an updated version of this patch that I've missed? > I don't recall seeing any updated version fixing this
As a matter of fact, when you say "use dma_slave_control API," you actually mean the dma_slave_config, right? Then, how is one supposed to use it in this case? Shall we be issuing a DMA_SLAVE_CONFIG call inside of the filter and check the return code? The problem is, that not all DMA controllers on sh-mobile SoCs can service the same slave devices. So, if we don't check in the filter we might well get an unsuitable DMA channel.
Thanks Guennadi --- Guennadi Liakhovetski, Ph.D. Freelance Open-Source Software Developer http://www.open-technology.de/
| |